1.1 C/C++ Library Manual for SHARC(R) Processors Revision 1.2, May 2014 Part Number 82-100118-01 Analog Devices, Inc. One Technology Way Norwood, Mass. 02062-9106 a Copyright Information (c)2014 Analog Devices, Inc., ALL RIGHTS RESERVED. This document may not be reproduced in any form without prior, express written consent from Analog Devices, Inc. Printed in the USA. Disclaimer Analog Devices, Inc. reserves the right to change this product without prior notice. Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use; nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under the patent rights of Analog Devices, Inc. Trademark and Service Mark Notice The Analog Devices logo, CrossCore, EngineerZone, EZ-KIT Lite, SHARC, and VisualDSP++ are registered trademarks of Analog Devices, Inc. All other brand and product names are trademarks or service marks of their respective owners. CONTENTS PREFACE Purpose of This Manual ............................................................ xxiii Intended Audience .................................................................... xxiii Manual Contents ....................................................................... xxiv What's New in This Manual ....................................................... xxiv Technical Support ....................................................................... xxv Supported Processors .................................................................. xxvi Product Information .................................................................. xxvi Analog Devices Web Site ..................................................... xxvii EngineerZone ...................................................................... xxvii Notation Conventions .............................................................. xxviii C/C++ RUN-TIME LIBRARY C and C++ Run-Time Libraries Guide ........................................... 1-2 Calling Library Functions ........................................................ 1-3 Linking Library Functions ....................................................... 1-3 Functional Breakdown ........................................................ 1-4 Library Location ................................................................. 1-5 Library Selection ................................................................. 1-6 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors iii Contents Library Naming .................................................................. 1-6 Library Startup Files ........................................................... 1-8 Library Attributes ................................................................... 1-8 Exceptions to the Attribute Conventions ........................... 1-12 Mapping Objects to FLASH Memory Using Attributes ...... 1-13 Working With Library Header Files ....................................... 1-13 adi_types.h ....................................................................... 1-15 assert.h ............................................................................. 1-15 ctype.h ............................................................................. 1-16 cycle_count.h ................................................................... 1-16 cycles.h ............................................................................ 1-17 errno.h ............................................................................. 1-17 float.h .............................................................................. 1-17 heap_debug.h ................................................................... 1-18 instrprof.h ........................................................................ 1-21 iso646.h ........................................................................... 1-21 libdyn.h ........................................................................... 1-21 limits.h ............................................................................ 1-22 locale.h ............................................................................ 1-22 math.h ............................................................................. 1-22 misra_types.h ................................................................... 1-24 pgo_hw.h ......................................................................... 1-24 setjmp.h ........................................................................... 1-24 signal.h ............................................................................ 1-24 iv CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Contents stdarg.h ............................................................................ 1-24 stdbool.h .......................................................................... 1-25 stddef.h ............................................................................ 1-25 stdfix.h ............................................................................. 1-25 stdint.h ............................................................................. 1-25 stdio.h .............................................................................. 1-27 stdlib.h ............................................................................. 1-29 string.h ............................................................................. 1-31 time.h ............................................................................... 1-31 Calling Library Functions From an ISR .................................. 1-33 Using the Libraries in a Multi-Threaded Environment ............ 1-34 Using Compiler Built-In C Library Functions ........................ 1-35 Abridged C++ Library Support .............................................. 1-36 Embedded C++ Library Header Files ................................. 1-37 complex ........................................................................ 1-37 exception ...................................................................... 1-37 fstream .......................................................................... 1-38 iomanip ........................................................................ 1-38 ios ................................................................................ 1-38 iosfwd ........................................................................... 1-38 iostream ........................................................................ 1-38 istream .......................................................................... 1-38 new .............................................................................. 1-38 ostream ......................................................................... 1-38 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors v Contents sstream ......................................................................... 1-39 stdexcept ...................................................................... 1-39 streambuf ..................................................................... 1-39 string ............................................................................ 1-39 strstream ...................................................................... 1-39 C++ Header Files for C Library Facilities ........................... 1-40 Embedded Standard Template Library Header Files ........... 1-41 algorithm ..................................................................... 1-41 deque ........................................................................... 1-41 functional ..................................................................... 1-41 hash_map ..................................................................... 1-41 hash_set ....................................................................... 1-41 iterator ......................................................................... 1-41 list ................................................................................ 1-42 map .............................................................................. 1-42 memory ........................................................................ 1-42 numeric ........................................................................ 1-42 queue ........................................................................... 1-42 set ................................................................................ 1-42 stack ............................................................................ 1-42 utility ........................................................................... 1-42 vector ........................................................................... 1-42 Header Files for C++ Library Compatibility ...................... 1-43 vi CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Contents Measuring Cycle Counts ........................................................ 1-43 Basic Cycle Counting Facility ............................................ 1-44 Cycle Counting Facility With Statistics .............................. 1-46 Using time.h to Measure Cycle Counts .............................. 1-49 Determining the Processor Clock Rate ............................... 1-50 Considerations When Measuring Cycle Counts .................. 1-51 File I/O Support .................................................................... 1-53 Fatal Error Handling ............................................................. 1-54 FatalError.xml ................................................................... 1-55 General Codes .................................................................. 1-55 Library Error Specific Codes .............................................. 1-56 Errno Values ..................................................................... 1-58 Documented Library Functions ................................................... 1-58 C Run-Time Library Reference .................................................... 1-65 abort .......................................................................................... 1-66 abs .............................................................................................. 1-67 absfx ........................................................................................... 1-68 acos ............................................................................................ 1-69 adi_dump_all_heaps ................................................................... 1-70 adi_dump_heap .......................................................................... 1-72 adi_fatal_error ............................................................................ 1-74 adi_fatal_exception ..................................................................... 1-76 adi_heap_debug_disable .............................................................. 1-78 adi_heap_debug_enable .............................................................. 1-80 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors vii Contents adi_heap_debug_end .................................................................. 1-82 adi_heap_debug_flush ................................................................ 1-84 adi_heap_debug_pause ............................................................... 1-86 adi_heap_debug_reset_guard_region ........................................... 1-88 adi_heap_debug_resume ............................................................. 1-90 adi_heap_debug_set_buffer ........................................................ 1-92 adi_heap_debug_set_call_stack_depth ........................................ 1-94 adi_heap_debug_set_error .......................................................... 1-96 adi_heap_debug_set_guard_region .............................................. 1-98 adi_heap_debug_set_ignore ...................................................... 1-101 adi_heap_debug_set_warning ................................................... 1-103 adi_verify_all_heaps ................................................................. 1-105 adi_verify_heap ........................................................................ 1-107 asctime ..................................................................................... 1-109 asin .......................................................................................... 1-111 atan .......................................................................................... 1-112 atan2 ........................................................................................ 1-113 atexit ....................................................................................... 1-114 atof .......................................................................................... 1-115 atoi .......................................................................................... 1-118 atol .......................................................................................... 1-119 atold ........................................................................................ 1-120 atoll ......................................................................................... 1-123 avg ........................................................................................... 1-124 viii CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Contents bitsfx ........................................................................................ 1-125 bsearch ..................................................................................... 1-126 calloc ........................................................................................ 1-129 ceil ........................................................................................... 1-131 clearerr ..................................................................................... 1-132 clip ........................................................................................... 1-134 clock ......................................................................................... 1-135 cos ............................................................................................ 1-137 cosh .......................................................................................... 1-138 count_ones ............................................................................... 1-139 countlsfx ................................................................................... 1-140 ctime ........................................................................................ 1-142 difftime .................................................................................... 1-144 div ............................................................................................ 1-146 divifx ........................................................................................ 1-148 dyn_AddHeap ........................................................................... 1-149 dyn_alloc .................................................................................. 1-151 dyn_AllocSectionMem .............................................................. 1-153 dyn_AllocSectionMemHeap ...................................................... 1-156 dyn_CopySectionContents ........................................................ 1-159 dyn_FreeEntryPointArray .......................................................... 1-161 dyn_FreeSectionMem ................................................................ 1-162 dyn_GetEntryPointArray .......................................................... 1-164 dyn_GetExpSymTab ................................................................. 1-167 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors ix Contents dyn_GetHeapForWidth ............................................................ 1-169 dyn_GetNumSections ............................................................... 1-171 dyn_GetSections ...................................................................... 1-173 dyn_GetStringTable .................................................................. 1-175 dyn_GetStringTableSize ............................................................ 1-177 dyn_heap_init .......................................................................... 1-179 dyn_LookupByName ................................................................ 1-181 dyn_RecordRelocOutOfRange .................................................. 1-184 dyn_Relocate ............................................................................ 1-186 dyn_RetrieveRelocOutOfRange ................................................ 1-188 dyn_RewriteImageToFile .......................................................... 1-190 dyn_SetSectionAddr ................................................................. 1-192 dyn_SetSectionMem ................................................................. 1-194 dyn_ValidateImage ................................................................... 1-196 exit ........................................................................................... 1-198 exp ........................................................................................... 1-199 fabs .......................................................................................... 1-200 fclose ........................................................................................ 1-201 feof .......................................................................................... 1-203 ferror ........................................................................................ 1-204 fflush ....................................................................................... 1-205 fgetc ......................................................................................... 1-206 fgetpos ..................................................................................... 1-208 fgets ......................................................................................... 1-210 x CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Contents fileno ........................................................................................ 1-212 floor ......................................................................................... 1-213 fmod ........................................................................................ 1-214 fopen ........................................................................................ 1-215 fprintf ....................................................................................... 1-217 fputc ......................................................................................... 1-223 fputs ......................................................................................... 1-224 fread ......................................................................................... 1-225 free ........................................................................................... 1-227 freopen ..................................................................................... 1-228 frexp ......................................................................................... 1-230 fscanf ........................................................................................ 1-232 fseek ......................................................................................... 1-237 fsetpos ...................................................................................... 1-239 ftell ........................................................................................... 1-240 fwrite ........................................................................................ 1-242 fxbits ........................................................................................ 1-244 fxdivi ........................................................................................ 1-245 getc .......................................................................................... 1-246 getchar ...................................................................................... 1-248 getenv ....................................................................................... 1-250 gets ........................................................................................... 1-251 gmtime ..................................................................................... 1-253 heap_calloc ............................................................................... 1-255 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors xi Contents heap_free .................................................................................. 1-257 heap_init .................................................................................. 1-259 heap_install .............................................................................. 1-261 heap_lookup ............................................................................ 1-263 heap_malloc ............................................................................. 1-265 heap_realloc ............................................................................. 1-267 heap_space_unused .................................................................. 1-270 heap_switch ............................................................................. 1-272 idivfx ....................................................................................... 1-274 instrprof_request_flush ............................................................. 1-275 ioctl ......................................................................................... 1-277 isalnum .................................................................................... 1-278 isalpha ...................................................................................... 1-279 iscntrl ....................................................................................... 1-280 isdigit ....................................................................................... 1-281 isgraph ..................................................................................... 1-282 isinf ......................................................................................... 1-283 islower ...................................................................................... 1-285 isnan ........................................................................................ 1-286 isprint ...................................................................................... 1-288 ispunct ..................................................................................... 1-289 isspace ...................................................................................... 1-290 isupper ..................................................................................... 1-292 isxdigit ..................................................................................... 1-293 xii CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Contents labs ........................................................................................... 1-294 lavg .......................................................................................... 1-295 lclip .......................................................................................... 1-296 lcount_ones .............................................................................. 1-297 ldexp ........................................................................................ 1-298 ldiv ........................................................................................... 1-299 llabs .......................................................................................... 1-301 llavg ......................................................................................... 1-302 llclip ......................................................................................... 1-303 llcount_ones ............................................................................. 1-304 lldiv .......................................................................................... 1-305 llmax ........................................................................................ 1-307 llmin ........................................................................................ 1-308 lmax ......................................................................................... 1-309 lmin ......................................................................................... 1-310 localeconv ................................................................................. 1-311 localtime ................................................................................... 1-314 log ............................................................................................ 1-316 log10 ........................................................................................ 1-317 longjmp .................................................................................... 1-318 malloc ...................................................................................... 1-320 max .......................................................................................... 1-321 memchr .................................................................................... 1-322 memcmp .................................................................................. 1-323 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors xiii Contents memcpy ................................................................................... 1-324 memmove ................................................................................ 1-325 memset .................................................................................... 1-326 min .......................................................................................... 1-327 mktime .................................................................................... 1-328 modf ........................................................................................ 1-331 mulifx ...................................................................................... 1-332 perror ....................................................................................... 1-333 pgo_hw_request_flush .............................................................. 1-335 pow .......................................................................................... 1-337 printf ....................................................................................... 1-338 putc ......................................................................................... 1-340 putchar .................................................................................... 1-341 puts .......................................................................................... 1-342 qsort ........................................................................................ 1-343 raise ......................................................................................... 1-345 rand ......................................................................................... 1-346 read_extmem ............................................................................ 1-347 realloc ...................................................................................... 1-349 remove ..................................................................................... 1-351 rename ..................................................................................... 1-352 rewind ...................................................................................... 1-354 roundfx .................................................................................... 1-356 scanf ........................................................................................ 1-358 xiv CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Contents setbuf ....................................................................................... 1-360 setjmp ...................................................................................... 1-362 setlocale .................................................................................... 1-364 setvbuf ...................................................................................... 1-365 signal ........................................................................................ 1-367 sin ............................................................................................ 1-369 sinh .......................................................................................... 1-370 snprintf .................................................................................... 1-371 space_unused ............................................................................ 1-373 sprintf ...................................................................................... 1-374 sqrt ........................................................................................... 1-376 srand ........................................................................................ 1-377 sscanf ........................................................................................ 1-378 strcat ........................................................................................ 1-380 strchr ........................................................................................ 1-381 strcmp ...................................................................................... 1-382 strcoll ....................................................................................... 1-383 strcpy ....................................................................................... 1-384 strcspn ...................................................................................... 1-385 strerror ..................................................................................... 1-386 strftime ..................................................................................... 1-387 strlen ........................................................................................ 1-391 strncat ...................................................................................... 1-392 strncmp .................................................................................... 1-393 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors xv Contents strncpy ..................................................................................... 1-394 strpbrk ..................................................................................... 1-395 strrchr ...................................................................................... 1-396 strspn ....................................................................................... 1-397 strstr ........................................................................................ 1-398 strtod ....................................................................................... 1-399 strtofxfx ................................................................................... 1-402 strtok ....................................................................................... 1-405 strtol ........................................................................................ 1-407 strtold ...................................................................................... 1-409 strtoll ....................................................................................... 1-412 strtoul ...................................................................................... 1-414 strtoull ..................................................................................... 1-416 strxfrm ..................................................................................... 1-418 system ...................................................................................... 1-420 tan ........................................................................................... 1-421 tanh ......................................................................................... 1-422 time ......................................................................................... 1-423 tolower ..................................................................................... 1-424 toupper .................................................................................... 1-425 ungetc ...................................................................................... 1-426 va_arg ...................................................................................... 1-428 va_end ..................................................................................... 1-431 va_start .................................................................................... 1-432 xvi CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Contents vfprintf ..................................................................................... 1-433 vprintf ...................................................................................... 1-435 vsnprintf ................................................................................... 1-437 vsprintf ..................................................................................... 1-439 write_extmem ........................................................................... 1-441 DSP RUN-TIME LIBRARY DSP Run-Time Library Guide ....................................................... 2-2 Calling DSP Library Functions ................................................ 2-2 Reentrancy .............................................................................. 2-3 Library Attributes .................................................................... 2-3 Working With Library Source Code ......................................... 2-3 DSP Header Files .................................................................... 2-4 asm_sprt.h .......................................................................... 2-5 cmatrix.h ............................................................................ 2-5 comm.h .............................................................................. 2-5 complex.h ........................................................................... 2-6 cvector.h ............................................................................. 2-7 filter.h ................................................................................ 2-7 filters.h ............................................................................... 2-9 macros.h ............................................................................. 2-9 math.h ................................................................................ 2-9 matrix.h ............................................................................ 2-11 platform_include.h ........................................................... 2-11 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors xvii Contents Header Files That Define Processor-Specific System Register Bits .............................................................. 2-12 Header Files That Allow Access to Memory-Mapped Registers From C/C++ Code ...................................... 2-13 stats.h .............................................................................. 2-14 sysreg.h ............................................................................ 2-14 trans.h .............................................................................. 2-14 vector.h ............................................................................ 2-15 window.h ......................................................................... 2-15 Built-In DSP Library Functions ............................................ 2-16 Implications of Using SIMD Mode ....................................... 2-17 Using Data in External Memory ............................................ 2-19 Documented Library Functions .................................................. 2-20 DSP Run-Time Library Reference ............................................... 2-24 a_compress ................................................................................. 2-25 a_expand .................................................................................... 2-27 alog ............................................................................................ 2-29 alog10 ........................................................................................ 2-30 arg ............................................................................................. 2-31 autocoh ...................................................................................... 2-33 autocorr ..................................................................................... 2-35 biquad ........................................................................................ 2-37 cabs ............................................................................................ 2-42 cadd ........................................................................................... 2-44 cartesian ..................................................................................... 2-45 xviii CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Contents cdiv ............................................................................................ 2-47 cexp ............................................................................................ 2-49 cfft ............................................................................................. 2-51 cfft_mag ..................................................................................... 2-54 cfftN .......................................................................................... 2-56 cfftN .......................................................................................... 2-60 cfftf ............................................................................................ 2-63 cmatmadd ................................................................................... 2-66 cmatmmlt ................................................................................... 2-68 cmatmsub ................................................................................... 2-71 cmatsadd .................................................................................... 2-73 cmatsmlt ..................................................................................... 2-75 cmatssub ..................................................................................... 2-77 cmlt ............................................................................................ 2-79 conj ............................................................................................ 2-80 convolve ..................................................................................... 2-81 copysign ..................................................................................... 2-83 cot .............................................................................................. 2-84 crosscoh ...................................................................................... 2-86 crosscorr ..................................................................................... 2-89 csub ............................................................................................ 2-92 cvecdot ....................................................................................... 2-93 cvecsadd ..................................................................................... 2-95 cvecsmlt ...................................................................................... 2-97 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors xix Contents cvecssub ..................................................................................... 2-99 cvecvadd ................................................................................... 2-101 cvecvmlt ................................................................................... 2-103 cvecvsub ................................................................................... 2-105 favg .......................................................................................... 2-107 fclip ......................................................................................... 2-108 fft_magnitude ........................................................................... 2-109 fftf_magnitude ......................................................................... 2-113 fir ............................................................................................ 2-116 fir_decima ................................................................................ 2-120 fir_interp .................................................................................. 2-123 firf ........................................................................................... 2-128 fmax ......................................................................................... 2-132 fmin ......................................................................................... 2-133 gen_bartlett .............................................................................. 2-134 gen_blackman .......................................................................... 2-136 gen_gaussian ............................................................................ 2-138 gen_hamming .......................................................................... 2-140 gen_hanning ............................................................................ 2-142 gen_harris ................................................................................ 2-144 gen_kaiser ................................................................................ 2-146 gen_rectangular ........................................................................ 2-148 gen_triangle ............................................................................. 2-150 gen_vonhann ............................................................................ 2-152 xx CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Contents histogram ................................................................................. 2-153 ifft ............................................................................................ 2-155 ifftf ........................................................................................... 2-158 ifftN ......................................................................................... 2-161 ifftN ......................................................................................... 2-165 iir ............................................................................................. 2-168 matinv ...................................................................................... 2-176 matmadd .................................................................................. 2-178 matmmlt .................................................................................. 2-180 matmsub .................................................................................. 2-182 matsadd .................................................................................... 2-184 matsmlt .................................................................................... 2-186 matssub .................................................................................... 2-188 mean ........................................................................................ 2-190 mu_compress ............................................................................ 2-191 mu_expand ............................................................................... 2-193 norm ........................................................................................ 2-195 polar ......................................................................................... 2-197 rfft ............................................................................................ 2-199 rfft_mag ................................................................................... 2-203 rfftf_2 ....................................................................................... 2-205 rfftN ......................................................................................... 2-208 rfftN ......................................................................................... 2-211 rms ........................................................................................... 2-215 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors xxi Contents rsqrt ......................................................................................... 2-217 transpm .................................................................................... 2-218 twidfft ...................................................................................... 2-220 twidfftf ..................................................................................... 2-223 var ........................................................................................... 2-226 vecdot ...................................................................................... 2-228 vecsadd .................................................................................... 2-230 vecsmlt ..................................................................................... 2-232 vecssub ..................................................................................... 2-234 vecvadd .................................................................................... 2-236 vecvmlt .................................................................................... 2-238 vecvsub .................................................................................... 2-240 zero_cross ................................................................................. 2-242 INDEX xxii CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors PREFACE Thank you for purchasing Analog Devices, Inc. development software for signal processing applications. Purpose of This Manual The C/C++ Library Manual contains information about the C/C++ and DSP run-time libraries for SHARC(R) (ADSP-21xxx) processors. It leads you through the process of using library routines and provides information about the ANSI standard header files and different libraries that are included with this release of the cc21k compiler. Intended Audience The primary audience for this manual is a programmer who is familiar with Analog Devices processors. This manual assumes that the audience has a working knowledge of the SHARC architecture and the C/C++ programming languages. Programmers who are unfamiliar with SHARC processors can use this manual, but they should supplement it with other texts (such as the appropriate hardware reference and programming reference manuals) that describe their target architecture. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors xxiii Manual Contents Manual Contents This manual contains: * Chapter 1, C/C++ Run-Time Library Describes how to use library functions and provides a complete C/C++ library function reference (for functions covered in the current compiler release) * Chapter 2, DSP Run-Time Library Describes how to use DSP library functions and provides a complete library function reference (for functions covered in the current compiler release) What's New in This Manual This is Revision 1.2 of the C/C++ Library Manual. It documents C/C++ and DSP libraries for all current SHARC processors listed in the CrossCore(R) Embedded Studio (CCES) online help. This revision corrects typographical errors and resolves document errata reported against the previous revision. xxiv CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Preface Technical Support You can reach Analog Devices processors and DSP technical support in the following ways: * Post your questions in the processors and DSP support community at EngineerZone(R): http://ez.analog.com/community/dsp * Submit your questions to technical support directly at: http://www.analog.com/support * E-mail your questions about processors, DSPs, and tools development software from CrossCore Embedded Studio or VisualDSP++(R): Choose Help > Email Support. This creates an e-mail to and automatically attaches your CrossCore Embedded Studio or VisualDSP++ version information and license.dat file. processor.tools.support@analog.com * E-mail your questions about processors and processor applications to: processor.support@analog.com or processor.china@analog.com (Greater China support) * Contact your Analog Devices sales office or authorized distributor. Locate one at: www.analog.com/adi-sales * Send questions by mail to: Processors and DSP Technical Support Analog Devices, Inc. Three Technology Way P.O. Box 9106 Norwood, MA 02062-9106 USA CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors xxv Supported Processors Supported Processors The name "SHARC" refers to a family of Analog Devices, Inc. high-performance 32-bit floating-point digital signal processors that can be used in speech, sound, graphics, and imaging applications. Refer to the CCES online help for a complete list of supported processors. Product Information Product information can be obtained from the Analog Devices Web site and the CCES online help. Analog Devices Web Site The Analog Devices Web site, www.analog.com, provides information about a broad range of products--analog integrated circuits, amplifiers, converters, and digital signal processors. To access a complete technical library for each processor family, go to http://www.analog.com/processors/technical_library. The manuals selection opens a list of current manuals related to the product as well as a link to the previous revisions of the manuals. When locating your manual title, note a possible errata check mark next to the title that leads to the current correction report against the manual. Also note, myAnalog is a free feature of the Analog Devices Web site that allows customization of a Web page to display only the latest information about products you are interested in. You can choose to receive weekly e-mail notifications containing updates to the Web pages that meet your interests, including documentation errata against all manuals. myAnalog xxvi CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Preface provides access to books, application notes, data sheets, code examples, and more. Visit myAnalog to sign up. If you are a registered user, just log on. Your user name is your e-mail address. EngineerZone EngineerZone is a technical support forum from Analog Devices. It allows you direct access to ADI technical support engineers. You can search FAQs and technical information to get quick answers to your embedded processing and DSP design questions. Use EngineerZone to connect with other DSP developers who face similar design challenges. You can also use this open forum to share knowledge and collaborate with the ADI support team and your peers. Visit http://ez.analog.com to sign up. Notation Conventions Text conventions used in this manual are identified and described as follows. Example Description File > Close Titles in bold style reference sections indicate the location of an item within the CrossCore Embedded Studio's menu system (for example, the Close command appears on the File menu). {this | that} Alternative required items in syntax descriptions appear within curly brackets and separated by vertical bars; read the example as this or that. One or the other is required. [this | that] Optional items in syntax descriptions appear within brackets and separated by vertical bars; read the example as an optional this or that. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors xxvii Notation Conventions Example Description [this,...] Optional item lists in syntax descriptions appear within brackets delimited by commas and terminated with an ellipsis; read the example as an optional comma-separated list of this. .SECTION Commands, directives, keywords, and feature names are in text with letter gothic font. filename Non-keyword placeholders appear in text with italic style format. xxviii Note: For correct operation, ... A Note provides supplementary information on a related topic. In the online version of this book, the word Note appears instead of this symbol. Caution: Incorrect device operation may result if ... Caution: Device damage may result if ... A Caution identifies conditions or inappropriate usage of the product that could lead to undesirable results or product damage. In the online version of this book, the word Caution appears instead of this symbol. Warning: Injury to device users may result if ... A Warning identifies conditions or inappropriate usage of the product that could lead to conditions that are potentially hazardous for devices users. In the online version of this book, the word Warning appears instead of this symbol. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1 C/C++ RUN-TIME LIBRARY The C and C++ run-time libraries are collections of functions, macros, and class templates that you can call from your source programs. Many functions are implemented in the ADSP-21xxx assembly language. C and C++ programs depend on library functions to perform operations that are basic to the C and C++ programming environments. These operations include memory allocations, character and string conversions, and math calculations. Using the library simplifies your software development by providing code for a variety of common needs. The sections of this chapter present the following information on the compiler: * C and C++ Run-Time Libraries Guide provides introductory information about the ANSI/ISO standard C and C++ libraries. It also provides information about the ANSI standard header files and built-in functions that are included with this release of the cc21k compiler. * C Run-Time Library Reference contains reference information about the C run-time library functions included with this release of the cc21k compiler. The cc21k compiler provides a broad collection of library functions, including those required by the ANSI standard and additional functions supplied by Analog Devices that are of value in signal processing applications. In addition to the standard C library, this release of the compiler software includes the Abridged C++ library, a conforming subset of the standard C++ library. The Abridged C++ library includes the embedded C++ and embedded standard template libraries. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-1 C and C++ Run-Time Libraries Guide This chapter describes the standard C/C++ library functions that are supported in the current release of the run-time libraries. Chapter 2, DSP Run-Time Library describes a number of signal processing, matrix, and statistical functions that assist code development. more information on the algorithms on which many of the C For library's math functions are based, see W. J, Cody and W. Waite, Software Manual for the Elementary Functions, Englewood Cliffs, New Jersey: Prentice Hall, 1980. For more information on the C++ library portion of the ANSI/ISO Standard for C++, see Plauger, P. J. (Preface), The Draft Standard C++ Library, Englewood Cliffs, New Jersey: Prentice Hall, 1994, (ISBN: 0131170031). The Abridged C++ library software documentation is located in the CCES online help. C and C++ Run-Time Libraries Guide The C and C++ run-time libraries contain routines that you can call from your source program. This section describes how to use the libraries and provides information on the following topics: * Calling Library Functions * Linking Library Functions * Library Attributes * Working With Library Header Files * Calling Library Functions From an ISR * Using the Libraries in a Multi-Threaded Environment * Using Compiler Built-In C Library Functions * Abridged C++ Library Support 1-2 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library * Measuring Cycle Counts * File I/O Support * Fatal Error Handling For information on the C library's contents, see C Run-Time Library Reference. For information on the Abridged C++ library's contents, see Abridged C++ Library Support. Calling Library Functions To use a C/C++ library function, call the function by name and give the appropriate arguments. The name and arguments for each function appear on the function's reference page. The reference pages appear in the C Run-Time Library Reference. Like other functions you use, library functions should be declared. Declarations are supplied in header files. For more information about the header files, see Working With Library Header Files. Function names are C/C++ function names. If you call a C/C++ run-time library function from an assembly program, you must use the assembly version of the function name (prefix an underscore on the name). For more information on the naming conventions, see Chapter 1 of the C/C++ Compiler Manual for SHARC Processors. You can use the archiver, , described in the Linker and Utili ties Manual, to build library archive files of your own functions. elfar Linking Library Functions When you call a run-time library function, the call creates a reference that the linker resolves when linking your program. One way to direct the linker to the library's location is to use the default Linker Description File (ADSP-.ldf). CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-3 C and C++ Run-Time Libraries Guide If you are not using the default . ldf file, then either add the appropriate library/libraries to the .ldf file used for your project, or use the compiler's -l switch to specify the library to be added to the link line. For example, the switches -lc -ldsp add libc.dlb and libdsp.dlb to the list of libraries to be searched by the linker. For more information on the .ldf file, see the Linker and Utilities Manual. Functional Breakdown The C/C++ run-time library is organized as several libraries: * Compiler support library - Contains internal functions that support the in-line code generated by the compiler; emulated arithmetic is a typical case. * C run-time library - Comprises all the functions that are defined by the ANSI standard, plus various Analog Devices extensions. * DSP run-time library - Contains additional library functions supplied by Analog Devices that provide services commonly required by DSP applications. * Heap debugging library - Contains debug versions of the heap support provided by the C/C++ run-time library, as well as some additional diagnostic functions relating to heap use. * Instrumented profiling library - Contains support routines for recording the cycles spent in each profiled function. * I/O library - Supports a subset of the C standard's I/O functionality. * Dynamic module loader library - Supports loading and using dynamically-loadable modules created using the elf2dyn utility. 1-4 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library In addition to regular run-time libraries, CCES has some additional libraries which provide variants of LibIO (the I/O run-time support library). These variants are: * - libraries which provide smaller versions of with more limited functionality. These smaller LibIO libraries can be used by specifying the following switch on the build command line: -flags-link -MD__LIBIO_LITE libio*_lite.dlb LibIO * - libraries which provide versions of LibIO with full support for the fixed-point format specifiers for the fract types. These libraries can be used by specifying the following switch on the build command line: -flags-link -MD__LIBIO_FX libio*_fx.dlb Library Location The C/C++ run-time libraries are provided in binary form in directories named sharc\lib\processor_rev_revision: * processor identifies which processor for which the library is built, and is the processor's name with the leading "ADSP-" stripped. * revision identifies for which silicon revision the library is built. For example, a revision of 0.1 would indicate that the library was built with the command-line switch -si-revision 0.1. So the directory sharc\lib\21469_rev_any contains libraries that have been built with -proc ADSP-21469 -si-revision any switches. The C/C++ run-time libraries are provided in source form, where available, in the directories named sharc\lib\src\libname, where libname indicates which library the source is used to build. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-5 C and C++ Run-Time Libraries Guide Library Selection The library directory used to link an application is selected through the -proc and -si-revision compiler switches, in conjunction with an XML configuration file. The -proc switch directs the compiler driver to read an XML configuration file from System\ArchDef, based on the selected processor. For example, a compiler switch of -proc ADSP-21469 would cause the compiler driver to read the ADSP-21469-compiler.xml file in System\ArchDef. Each such XML file indicates which library subdirectory should be used, for supported silicon revision of that processor. For example, the XML file for the ADSP-21469 processor indicates that for silicon revision 0.2, the library directory to use is sharc\lib\21469_rev_any. A given library subdirectory might support more than one silicon revision. In such cases, the XML file will give the same library subdirectory for several silicon revisions. Library Naming Within the library subdirectories, the libraries follow a consistent naming scheme, so that the library's name will be lib.dlb, where name indicates the library's purpose, and attrs is a sequence of zero or more attributes. The libraries' names are given in Table 1-2, and the attributes are enumerated in Table 1-1. 1-6 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Table 1-1. Library Name Attributes Attribute Meaning mt Built with -threads, for use in a multi-threaded environment x Built with -eh -rtti, to enable C++ exception-handling Table 1-2. C/C++ Library Names Description Library Name Compiler support library libcc*.dlb C run-time library libc*.dlb C++ run-time library libcpp*.dlb DSP run-time library libdsp*.dlb Heap debugging library libheapdbg*.dlb Instrumented profiling library libprofile*.dlb I/O run-time library libio*.dlb I/O run-time library with no support for alternative device drivers or printf("%a") libio_lite*.dlb I/O run-time library with full support for the fixed-point format specifiers libiofx*.dlb Loader library for dynamically-loadable modules (DLMs) libdyn*.dlb Comments Operates on DLMs produced by elf2dyn. Refer to the Loader and Utilities Manual. The run-time libraries and binary files for the ADSP-21160 processors in this table have been compiled with the -workaround rframe compiler switch, while those for the ADSP-21161 processors have been compiled with the -workaround 21161-anomaly-45 switch. The libraries for the ADSP-214xx processor are built in short-word mode. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-7 C and C++ Run-Time Libraries Guide Library Startup Files The library subdirectories also contain object files which contain the "runtime header", or "C run-time" (CRT) startup code. These files contain the code that is executed when your application first starts running; it is this code that configures the expected C/C++ environment and passes control to your main() function. Startup files have names of the form procid_attrs_hdr.doj: * procid indicates which processor the startup code is for; for ADSP-211xx, ADSP-212xx and ADSP-213xx processors, this is the last three digits of the processor's name. For other processors, this is the five digits of the processor's name. * attrs is a list of zero or more names indicating which features are configured by the startup code. These attributes and their meanings are listed in Table 1-3. Table 1-3. Startup File Attributes Attribute Meaning _cpp C++ startup file _sov Enables stack overflow detection Library Attributes The run-time libraries make use of file attributes. (See Chapter 1 of the C/C++ Compiler Manual for SHARC Processors for more details on how to use file attributes.) Each library function has a defined set of file attributes that are listed in Table 1-4. For each object obj in the run-time libraries the following is true. 1-8 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Table 1-4. Run-Time Library Object Attributes Attribute Name Meaning of Attribute and Value libGroup A potentially multi-valued attribute. Each value is the name of a header file that either defines obj, or that defines a function that calls obj. libName The name of the library that contains obj. For example, suppose that obj were part of libdsp.dlb, then the value of the attribute would be libdsp. libFunc The name of all the functions in obj. libFunc will have multiple values -both the C, and assembly linkage names will be listed. libFunc will also contain all the published C and assembly linkage names of objects in obj's library that call into obj. prefersMem One of three values: internal, external or any. If obj contains a function that is likely to be application performance critical, it will be marked as internal. Most DSP run-time library functions fit into the internal category. If a function is deemed unlikely to be essential for achieving the necessary performance it will be marked as external (all the I/O library functions fall into this category). The default .ldf files use this attribute to place code and data optimally. prefersMemNum Analogous to prefersMem but takes a numeric string value. The attribute can be used in .ldf files to provide a greater measure of control over the placement of binary object files than is available using the prefersMem attribute. The values "30", "50", and "70" correspond to the prefersMem values internal, any, and external respectively. The default .ldf files use the prefersMem attribute in preference to the prefersMemNum attribute to specify the optimum placement of files. FuncName Multi-valued attribute whose values are all the assembler linkage names of the defined names in obj. If an object in the run-time library calls into another object in the same library, whether it is internal or publicly visible, the called object will inherit extra libGroup and libFunc values from the caller. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-9 C and C++ Run-Time Libraries Guide The following example demonstrates how attributes would look in a small example library libfunc.dlb that comprises three objects: func1.doj, func2.doj and subfunc.doj. These objects are built from the following source modules: File: func1.h void func1(void); File: func2.h void func2(void); File: func1.c #include func1.h" void func1(void) { /* Compiles to func1.doj */ subfunc(); } File: func2.c #include "func2.h" void func2(void) { /* Compiles to func2.doj */ subfunc(); } File: subfunc.c void subfunc(void) { /* Compiles to subfunc.doj */ } The objects in libfunc.dlb have the attributes as defined in Table 1-5. 1-10 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Table 1-5. Attribute Values in libfunc.dlb Attribute Value func1.doj libGroup libName libFunc libFunc FuncName prefersMem prefersMemNum func1.h libfunc _func1 func1 _func1 any(1) func2.doj libGroup libName libFunc libFunc FuncName prefersMem prefersMemNum subfunc.doj libGroup libGroup libName libFunc libFunc libFunc libFunc libFunc libFunc FuncName prefersMem prefersMemNum 50 func2.h libfunc _func2 func2 _func2 internal(2) 30 func1.h func2.h(3) libfunc _func1 func1 _func2 func2 _subfunc subfunc _subfunc internal(4) 30 1 func1.doj will not be performance critical, based on its normal usage. 2 func2.doj will be performance critical in many applications, based on its normal usage. 3 libGroup contains the union of the libGroup attributes of the two calling objects. 4 prefersMem contains the highest priority of all the calling objects. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-11 C and C++ Run-Time Libraries Guide Exceptions to the Attribute Conventions The library attribute convention has the following exceptions: The C++ support libraries (libcpp*.dlb) all contain functions that have C++ linkage. Functions written in C++ have their functions names encoded (often referred to as name mangling) to allow for the overloading of parameter types. The function name encoding includes all the parameter types, the return type and the namespace within which the function is declared. Whenever a function's name is encoded, the encoded name is used as the value for the libFunc attribute. Table 1-6 lists additional libGroup attribute values. Table 1-6. Additional libGroup Attribute Values Value Meaning floating_point_support Compiler support routines for floating-point arithmetic fixed_point_support Compiler support routines for native fixed-point types integer_support Compiler support routines for integer arithmetic runtime_support Other run-time functions that do not fit into any of the above categories startup One-time initialization functions called prior to the invocation of main runtime_checking Run-Time checks to provide support for dynamic checks stack_overflow_detection Run-Time checks to support detection of stack overflow libprofile Run-Time functions to support profiling Objects with any of the libGroup attribute values listed in Table 1-6 will not contain any libGroup or libFunc attributes from any calling objects. 1-12 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Table 1-7 presents a summary of the default memory placement using prefersMem. Table 1-7. Default Memory Placement Summary Library Placement libcpp*.dlb any libio*.dlb external libdsp*.dlb internal libc*.dlb any except for the windowing functions and functions which generate a twiddle table which are external except for the stdio.h functions, which are external, and qsort, which is internal Most of the functions contained within the DSP run-time library (libdsp*.dlb) have prefersMem=internal, because it is likely that any function called in this run-time library will make up a significant part of an application's cycle count. Mapping Objects to FLASH Memory Using Attributes When using the Memory Initializer to initialize code and data areas from flash memory, code and data used during the process of initialization must be mapped to flash memory to ensure it is available during boot-up. The requiredForROMBoot attribute is specified on library objects that contain such code and data and can be used in the .ldf file to perform the required mapping. See the Linker and Utilities Manual for further information on memory initialization. Working With Library Header Files When you use a library function in your program, you should also include the function's header file with the #include preprocessor command. The header file for each function is identified in the Synopsis section of the function's reference page. Header files contain function prototypes. The CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-13 C and C++ Run-Time Libraries Guide compiler uses these prototypes to check that each function is called with the correct arguments. A list of the header files that are supplied with this release of the cc21k compiler appears in Table 1-8. You should use a C standard text to augment the information supplied in this chapter. Table 1-8. Standard C Run-Time Library Header Files Header Purpose Standard adi_types.h Type definitions Analog Extension assert.h Diagnostics ANSI ctype.h Character handling ANSI cycle_count.h Basic cycle counting Analog Extension cycles.h Cycle counting with statistics Analog Extension errno.h Error handling ANSI float.h Floating point ANSI heap_debug.h Macros and prototypes for heap debugging Analog Extension instrprof.h Instrumented profiling support (on page 1-21) Analog Extension iso646.h Boolean operators ANSI libdyn.h Dynamically-loadable modules (on page 1-21) Analog Extension limits.h Limits ANSI locale.h Localization ANSI math.h Mathematics ANSI misra_types.h Exact-width integer types MISRA-C:2004 pgo_hw.h Profile-guided optimization support (on page 1-24) Analog Extension setjmp.h Non-local jumps ANSI signal.h Signal handling ANSI stdarg.h Variable arguments ANSI stdbool.h Boolean macros ANSI stddef.h Standard definitions ANSI 1-14 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Table 1-8. Standard C Run-Time Library Header Files (Cont'd) Header Purpose Standard stdfix.h Fixed point ISO/IEC TR 18037 stdint.h Exact width integer types ANSI stdio.h Input/output ANSI stdlib.h Standard library ANSI string.h String handling ANSI time.h Date and time ANSI The following sections provide descriptions of the header files contained in the C library. The header files are listed in alphabetical order. adi_types.h The adi_types.h header file contains the type definitions for char_t, float32_t, float64_t, and also includes both stdint.h and stdbool.h. assert.h The assert.h header file defines the assert macro, which can be used to insert run-time diagnostics into a source file. The macro normally tests (asserts) that an expression is true. If the expression is false, then the macro will first print an error message, and will then call the abort function to terminate the application. The message displayed by the assert macro will be of the form: ASSERT [expression] fails at "filename": linenumber Note that the message includes the following information: * filename - the name of the source file * linenumber - the current line number in the source file * expression - the expression tested CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-15 C and C++ Run-Time Libraries Guide However if the macro NDEBUG is defined at the point at which the assert.h header file is included in the source file, then the assert macro will be defined as a null macro and no run-time diagnostics will be generated. The strings associated with assert.h can be assigned to slower, more plentiful memory (and therefore free up faster memory) by placing a default_section pragma above the sections of code containing the asserts. For example: #pragma default_section(STRINGS,"seg_sram") Note that the pragma will affect the placement of all strings, and not just the ones associated with using the ASSERT macro. For more information about using the pragma, see the section "Linking Control Pragmas" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors. An alternative to using the default_section pragma is to use the compiler's -section switch (for example -section strings=seg_sram). You can accomplish this in one of two ways: * Use the command line. * Use the IDE: Project > Properties > C/C++ Build > Settings > Compiler > Additional Options. ctype.h The ctype.h header file contains functions for character handling, such as isalpha, tolower, etc. For a list of library functions that use this header, see Table 1-21 on page 1-59. cycle_count.h The cycle_count.h header file provides an inexpensive method for benchmarking C-written source by defining basic facilities for measuring cycle 1-16 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library counts. The facilities provided are based upon two macros, and a data type which are described in more detail in the section Measuring Cycle Counts. cycles.h The cycles.h header file defines a set of five macros and an associated data type that may be used to measure the cycle counts used by a section of C-written source. The macros can record how many times a particular piece of code has been executed and also the minimum, average, and maximum number of cycles used. The facilities that are available via this header file are described in the section Measuring Cycle Counts. errno.h The errno.h header file provides access to errno and also defines macros for associated error codes. This facility is not, in general, supported by the rest of the library. float.h The float.h header file defines the properties of the floating-point data types that are implemented by the compiler--that is, float, double, and long double. These properties are defined as macros and include the following for each supported data type: * the maximum and minimum value (for example, FLT_MAX and FLT_MIN) * the maximum and minimum power of ten (for example, FLT_MAX_10_EXP and FLT_MIN_10_EXP) * the precision available expressed in terms of decimal digits (for example, FLT_DIG) * a constant that represents the smallest value that may added to 1.0 and still result in a change of value (for example, FLT_EPSILON) CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-17 C and C++ Run-Time Libraries Guide Note that the set of macros that define the properties of the double data type will have the same values as the corresponding set of macros for the float type when doubles are defined to be 32 bits wide, and they will have the same value as the macros for the long double data type when doubles are defined to be 64 bits wide (use the -double-size[-32|-64] compiler switch). heap_debug.h The heap_debug.h header file defines a set of functions and macros for configuring and manipulating the heap debugging library. For more information on heap debugging, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. When the macro _HEAP_DEBUG is not defined, the functions defined in heap_debug.h are replaced by simple statements representing a successful return from that function. This ensures that any code using these functions will link and operate as expected without any performance degradation when heap debugging is disabled. Configuration macros are provided in this file, which represent the values of the bit-fields used to control the behavior of the heap debugging. These configuration macros are shown in Table 1-9. 1-18 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Table 1-9. Configuration Macros for Heap Debugging Macro Use _HEAP_STDERR_DIAG Enable/disable diagnostics about heap usage via stderr _HEAP_HPL_GEN Enable/disable generation of the .hpl file used for heap debugging report _HEAP_TRACK_USAGE Enable/disable tracking of heap usage These macros can be used as parameters to adi_heap_debug_enable and adi_heap_debug_disable to enable or disable features at runtime. Tracking of heap usage is implicitly enabled when either report generation or run-time diagnostics are enabled at runtime. For more information see the section "Enabling And Disabling Features" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Macros representing various categories of heap error are defined in heap_debug.h. These values can be used as parameters to the functions adi_heap_debug_set_error, adi_heap_debug_set_ignore and adi_heap_debug_set_warning at runtime, or as definitions for the "C" unsigned long variables adi_heap_debug_error, __heap_debug_ignore and __heap_debug_warning at build-time in order to configure the severity of these error types when runtime diagnostics are enabled. These error type macros are shown in Table 1-10. For more information on using these macros, see the section "Setting The Severity Of Error Messages" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-19 C and C++ Run-Time Libraries Guide Table 1-10. Error Type Macros for Heap Debugging Macro Error _HEAP_ERROR_UNKNOWN An unknown error has occurred _HEAP_ERROR_FAILED An allocation has been unsuccessful _HEAP_ERROR_ALLOCATION_OF_ZERO An allocation has been requested with size of zero _HEAP_ERROR_NULL_PTR A null pointer has been passed where not expected _HEAP_ERROR_INVALID_ADDRESS A pointer has been passed which doesn't correspond to a block on the heap _HEAP_ERROR_BLOCK_IS_CORRUPT Corruption has been detected in the heap _HEAP_ERROR_FREE_OF_FREE A deallocation of an already de-allocated block has been requested _HEAP_ERROR_FUNCTION_MISMATCH An unexpected function is being used to de-allocate a block (i.e. calling free on an block allocated by new) _HEAP_ERROR_UNFREED_BLOCK A memory leak has been detected _HEAP_ERROR_WRONG_HEAP A heap operation has the wrong heap index specified _HEAP_ERROR_INVALID_INPUT An invalid parameter has been passed to a heap debugging function _HEAP_ERROR_INTERNAL An internal error has occurred _HEAP_ERROR_IN_ISR The heap has been used within an interrupt _HEAP_ERROR_MISSING_OUTPUT Report output has been lost due to insufficient or no buffer space _HEAP_ERROR_ALL Refers to all of the above errors collectively 1-20 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library instrprof.h The instrprof.h header file declares user-callable functions in support of instrumented profiling. For more information, see "Profiling With Instrumented Code" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. iso646.h The iso646.h header file defines symbolic names for certain C operators; the symbolic names and their associated value are shown in Table 1-11. Table 1-11. Symbolic Names Defined in iso646.h Symbolic Name Equivalent and && and_eq &= bitand & bitor | compl ~ not ! not_eq != or || or_eq |= xor ^ xor_eq ^= symbolic names have the same name as the C++ keywords that The are accepted by the compiler when the switch is specified. -alttok libdyn.h The libdyn.h header file contains type definitions and function declarations for loading dynamically-loadable modules (DLMs) that have been CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-21 C and C++ Run-Time Libraries Guide produced by the elf2dyn utility. For more information on using elf2dyn, refer to the Loader and Utilities Manual. For information on using creating and using DLMs, refer to the System Run-Time Documentation in the online help. limits.h The limits.h header file contains definitions of maximum and minimum values for each C data type other than floating-point. locale.h The locale.h header file contains definitions for expressing numeric, monetary, time, and other data. For a list of library functions that use this header, see Table 1-24. math.h The math.h header file includes trigonometric, power, logarithmic, exponential, and other miscellaneous functions. The library contains the functions specified by the C standard along with implementations for the data types float and long double. For a list of library functions that use this header, see Table 1-25. For every function that is defined to return a double, the math.h header file also defines corresponding functions that return a float and a long double. The names of the float functions are the same as the equivalent double function with f appended to its name. Similarly, the names of the long double functions are the same as the double function with d appended to its name. 1-22 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library For example, the header file contains the following prototypes for the sine function: float sinf (float x); double sin (double x); long double sind (long double x); When the compiler is treating double as 32 bits, the header file arranges that all references to the double functions are directed to the equivalent float function (with the suffix f). This allows you to use the un-suffixed names with arguments of type double, regardless of whether doubles are 32 or 64 bits long. This header file also provides prototypes for a number of additional math functions provided by Analog Devices, such as favg, fmax, fclip, and copysign. Refer to Chapter 2, DSP Run-Time Library for more information about these additional functions. The math.h header file also defines the macro HUGE_VAL. This macro evaluates to the maximum positive value that the type double can support. The macros EDOM and ERANGE, defined in errno.h, are used by math.h functions to indicate domain and range errors. A domain error occurs when an input argument is outside the domain of the function. C Run-Time Library Reference lists the specific cases that cause errno to be set to EDOM, and the associated return values. A range error occurs when the result of a function cannot be represented in the return type. If the result overflows, the function returns the value HUGE_VAL with the appropriate sign. If the result underflows, the function returns a zero without indicating a range error. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-23 C and C++ Run-Time Libraries Guide misra_types.h The misra_types.h header file contains definitions of exact-width data types, as defined in stdint.h and stdbool.h, plus data types char_t, float32_t and float64_t types. pgo_hw.h The pgo_hw.h header file declares user-callable functions in support of profile-guided optimization, when used with hardware rather than a simulator. For more information, see "Profile Guided Optimization and Code Coverage" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. setjmp.h The setjmp.h header file contains setjmp and longjmp for non-local jumps. For a list of library functions that use this header, see Table 1-26. signal.h The signal.h header file provides function prototypes for the standard ANSI signal.h routines. For a list of library functions that use this header, see Table 1-27. stdarg.h The stdarg.h header file contains definitions needed for functions that accept a variable number of arguments. Programs that call such functions must include a prototype for the functions referenced. For a list of library functions that use this header, see Table 1-28. 1-24 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library stdbool.h The stdbool.h header file contains three boolean related macros (true, false and __bool_true_false_are_defined) and an associated data type (bool). This header file was introduced in the C99 standard library. stddef.h The stddef.h header file contains a few common definitions useful for portable programs, such as size_t. stdfix.h The stdfix.h file contains function prototypes and macro definitions to support the native fixed-point type fract as defined by the ISO/IEC Technical Report 18037. The inclusion of this header file enables the fract keyword as an alias for _Fract. A discussion of support for native fixed-point types is given in Using Native Fixed-Point Types in the C/C++ Compiler Manual for SHARC Processors. stdint.h The stdint.h header file contains various exact-width integer types along with associated minimum and maximum values. The stdint.h header file was introduced in the C99 standard library. Table 1-12 describes each type with regard to MIN and MAX macros. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-25 C and C++ Run-Time Libraries Guide Table 1-12. Exact-Width Integer Types Type Common Equivalent MIN MAX int32_t int INT32_MIN INT32_MAX int64_t long long INT64_MIN INT64_MAX uint32_t unsigned int 0 UINT32_MAX uint64_t unsigned long long 0 UINT64_MAX int_least8_t int INT_LEAST8_MIN INT_LEAST8_MAX int_least16_t int INT_LEAST16_MIN INT_LEAST16_MAX int_least32_t int INT_LEAST32_MIN INT_LEAST32_MAX int_least64_t long long INT_LEAST64_MIN INT_LEAST64_MAX uint_least8_t unsigned int 0 UINT_LEAST8_MAX uint_least16_t unsigned int 0 UINT_LEAST16_MAX uint_least32_t unsigned int 0 UINT_LEAST32_MAX uint_least64_t unsigned long long 0 UINT_LEAST64_MAX int_fast8_t int INT_FAST8_MIN INT_FAST8_MAX int_fast16_t int INT_FAST16_MIN INT_FAST16_MAX int_fast32_t int INT_FAST32_MIN INT_FAST32_MAX int_fast64_t long long INT_FAST64_MIN INT_FAST64_MAX uint_fast8_t unsigned int 0 UINT_FAST8_MAX uint_fast16_t unsigned int 0 UINT_FAST16_MAX uint_fast32_t unsigned int 0 UINT_FAST32_MAX uint_fast64_t unsigned int 0 UINT_FAST64_MAX intmax_t int INTMAX_MIN INTMAX_MAX intptr_t int INTPTR_MIN INTPTR_MAX uintmax_t unsigned int 0 UINTMAX_MAX uintptr_t unsigned int 0 UINTPTR_MAX 1-26 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Table 1-13 describes MIN and MAX macros defined for typedefs in other headings. Table 1-13. MIN and MAX Macros for typedefs in Other Headings Type MIN MAX ptrdiff_t PTRDIFF_MIN PTRDIFF_MAX sig_atomic_t SIG_ATOMIC_MIN SIG_ATOMIC_MAX size_t 0 SIZE_MAX wchar_t WCHAR_MIN WCHAR_MAX wint_t WINT_MIN WINT_MAX Macros for minimum-width integer constants include: INT8_C(x), INT16_C(x), INT32_C(x), UINT8_C(x), UINT16_C(x), UINT32_C(x) INT64_C(x) and UINT64_C(x). Macros for greatest-width integer constants include INTMAX_C(x) and UINTMAX_C(x). stdio.h The stdio.h header file defines a set of functions, macros, and data types for performing input and output. Applications that use the facilities of this header file should link with the I/O library libio.dlb in the same way as linking with the C run-time library (see Linking Library Functions). The library is thread-safe but it is not interrupt-safe and should not therefore be called either directly or indirectly from an interrupt service routine. The compiler uses definitions within the header file to select an appropriate set of functions that correspond to the currently selected size of type double (either 32 bits or 64 bits). Any source file that uses the facilities of stdio.h must therefore include the header file. Failure to include the header file results in a linker failure as the compiler must see a correct function prototype in order to generate the correct calling sequence. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-27 C and C++ Run-Time Libraries Guide The default I/O library does not support input and output of fixed-point values in floating-point format with the r and R format specifiers in the printf and scanf family of functions. These will be printed in hexadecimal format. If you wish to include full support for the r and R format specifiers, link your application with the fixed-point I/O library, using the -flags-link -MD__LIBIO_FX switch. The implementation of both I/O libraries is based on a simple interface provided by the CCES simulator and EZ-KIT Lite(R) systems; for further details of this interface, refer to the System Run-Time Documentation in the online help. The following restrictions apply to this software release: * The functions tmpfile and tmpnam are not available * The functions rename and remove are always delegated to the current default device driver * Positioning within a file that has been opened as a text stream is only supported if the lines within the file are terminated by the character sequence \r\n * Support for formatted reading and writing of data of long type is only supported if an application is built with the -double-size-64 switch double At program termination, the host environment closes down any physical connection between the application and an opened file. However, the I/O library does not implicitly close any opened streams to avoid unnecessary overheads (particularly with respect to memory occupancy). Thus, unless explicit action is taken by an application, any unflushed output may be lost. Any output generated by printf is always flushed but output generated by other library functions, such as putchar, fwrite, and fprintf, is not automatically flushed. Applications should therefore arrange to close down any 1-28 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library streams that they open. Note that the function reference fflush (NULL); flushes the buffers of all opened streams. opened stream is allocated a buffer which either contains data Each from an input file or output from a program. For text streams, this data is held in the form of 8-bit characters that are packed into 32-bit memory locations. Due to internal mechanisms used to unpack and pack this data, the buffer must not reside at a memory location that is greater than the address 0x3fffffff. Since the stdio library allocates buffers from the heap, this restriction implies that the heap should not be placed at address 0x40000000 or above. The restriction may be avoided by using the setvbuf function to allocate the buffer from alternative memory, as in the following example. #include char buffer[BUFSIZ]; setvbuf(stdout,buffer,_IOLBF,BUFSIZ); printf("Hello World\n"); This example assumes that the buffer resides at a memory location that is less than 0x40000000. For a list of library functions that use this header, see Table 1-30. stdlib.h The stdlib.h header file offers general utilities specified by the C standard. These include some integer math functions, such as abs, div, and rand; general string-to-numeric conversions; memory allocation functions, such as malloc and free; and termination functions, such as exit. This library also contains miscellaneous functions such as bsearch and qsort. This header file also provides prototypes for a number of additional integer math functions provided by Analog Devices, such as avg, max, and CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-29 C and C++ Run-Time Libraries Guide clip. Table 1-14 is a summary of the additional library functions defined by the stdlib.h header file. functions exist as both integer and floating point functions. Some The floating point functions typically have an prefix. Make sure f you use the correct type. Table 1-14. Standard Library - Additional Functions Description Prototype Average int avg (int a, int b); long lavg (long a, long b); long long llavg (long long a, long long b); Clip int clip (int a, int b); long lclip (long a, long b); long long llclip (long long a, long long b); Count bits set int count_ones (int a); int lcount_ones (long a); int llcount_ones (long long a); Maximum int max (int a, int b); long lmax (long a, long b); long long llmax (long long a, long long b); Minimum int min (int a, int b); long lmin (long a, long b); long long llmin (long long a, long long b); Multiple heaps for dynamic memory allocation void *heap_calloc(int heap_index, size_t nelem, size_t size); void heap_free(int heap_index, void *ptr); int heap_init(int index); int heap_install(void *base, size_t size, int userid); int heap_lookup(int userid); void *heap_malloc(int heap_index, size_t size); void *heap_realloc(int heap_index, void *ptr, size_t size); int heap_space_unused(int index); int heap_switch(int heapid); int space_unused(void); 1-30 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library A number of functions, including abs, avg, max, min, and clip, are implemented via intrinsics (provided the header file has been #include'd) that map to single-cycle machine instructions. header file is not included, the library implementation is Ifusedtheinstead--at a considerable loss in efficiency. For a list of library functions that use this header, see Table 1-31. string.h The string.h header file contains string handling functions, including strcpy and memcpy. For a list of library functions that use this header, see Table 1-32. time.h The time.h header file provides functions, data types, and a macro for expressing and manipulating date and time information. The header file defines two fundamental data types: time_t and clock_t. The time_t data type is used for values that represent the number of seconds that have elapsed since a known epoch; values of this form are known as a calendar time. In this implementation, the epoch starts on 1st January, 1970, and calendar times before this date are represented as negative values. A calendar time may also be represented in a more versatile way as a broken-down time which is a structured variable of the following form: struct tm { int tm_sec; /* seconds after the minute [0,61] */ int tm_min; /* minutes after the hour [0,59] */ int tm_hour; /* hours after midnight [0,23] */ int tm_mday; /* day of the month [1,31] */ int tm_mon; /* months since January [0,11] */ int tm_year; /* years since 1900 */ CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-31 C and C++ Run-Time Libraries Guide int tm_wday; /* days since Sunday [0, 6] */ int tm_yday; /* days since January 1st [0,365] */ int tm_isdst; /* Daylight Saving flag */ }; implementation does not support either the Daylight Saving This flag in the structure struct tm; nor does it support the concept of time zones. All calendar times are therefore assumed to relate to Greenwich Mean Time (Coordinated Universal Time or UTC). The clock_t data type is associated with the number of implementation-dependent processor "ticks" used since an arbitrary starting point. By default the data type is equivalent to the long data type and can only be used to measure an elapsed time of a small number of seconds (depending upon the processor's clock speed). To measure a longer time span requires an alternative definition of the data type. If the macro __LONG_LONG_PROCESSOR_TIME__ is defined at compile-time (either before including the header file time.h, or by using the compile-time switch -D__LONG_LONG_PROCESSOR_TIME__), the clock_t data type will be typedef'd as a long long, which should be sufficient to record an elapsed time for the most demanding application. The header file sets the CLOCKS_PER_SEC macro to the number of processor cycles per second and this macro can therefore be used to convert data of type clock_t into seconds, normally by using floating-point arithmetic to divide it into the result returned by the clock function. the processor speed is a property of a particular chip and Init isgeneral, therefore recommended that the value to which this macro is set is verified independently before it is used by an application. 1-32 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library In this version of the C/C++ compiler, the CLOCKS_PER_SEC macro is set by one of the following (in descending order of precedence): * Via the -DCLOCKS_PER_SEC= compile-time switch * Via Project > Properties > C/C++ Build > Settings > Compiler > Processor > Processor speed (MHz) * From the header file cycles.h For a list of library functions that use this header, see Table 1-33. Calling Library Functions From an ISR Not all C run-time library functions are interrupt-safe (and can therefore be called from an interrupt service routine). For a run-time function to be classified as interrupt-safe, it must: * Not update any global data, such as errno, and * Not write to (or maintain) any private static data It is recommended therefore that none of the functions defined in the header file math.h, nor the string conversion functions defined in stdlib.h, be called from an ISR, as these functions are commonly defined to update the global variable errno. Similarly, the functions defined in the stdio.h header file maintain static tables for currently opened streams and should not be called from an ISR. The memory allocation routines malloc, calloc, realloc, free, the C++ operators new and delete, and any variants, read and update global tables and are not interrupt-safe. The heap debugging library can detect calls to memory allocation routines from an ISR, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-33 C and C++ Run-Time Libraries Guide Several other library functions are not interrupt-safe because they make use of private static data. These functions are: asctime gmtime localtime rand srand strtok While not all C run-time library functions are interrupt-safe, versions of the functions are available that are thread-safe and may be used in a multi-threaded environment. These library functions can be found in the run-time libraries that have the suffix mt in their filename. Using the Libraries in a Multi-Threaded Environment It is sometimes desirable for there to be several instances of a given library function to be active at any one time. Two examples of such a requirement are: * An interrupt or other external event invokes a function, while the application is also executing that function, * An application that runs in a multi-threaded environment, such as an RTOS, and more than one thread executes the function concurrently. The majority of the functions in the C and C++ run-time libraries are safe in this regard and may be called in either of the above schemes; this is because the functions operate on parameters passed in by the caller and they do not maintain private static storage, and they do not access non-constant global data. 1-34 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library A subset of the library functions however either make use of private storage or they operate on shared resources (such as FILE pointers). This can lead to undefined behavior if two instances of a function simultaneously access the same data. The issues associated with calling such library functions via an interrupt or other external event is discussed in the section Calling Library Functions From an ISR. A CCES installation contains versions of the C and C++ libraries that may be used in a multi-threaded environment. These libraries have recursive locking mechanisms so that shared resources, such as stdio FILE tables and buffers, are only updated by a single function instance at any given time. The libraries also make use of local-storage routines for thread-local private copies of data, and for the variable errno (each thread therefore has its own copy of errno). Note that the DSP run-time library (which is described in DSP Run-Time Library, is thread-safe and may be used in any multi-threaded environment. Using Compiler Built-In C Library Functions The C compiler built-in functions (sometimes called intrinsics) are functions that the compiler immediately recognizes and replaces with inline assembly code instead of a function call. For example, the absolute value function, abs(), is recognized by the compiler, which subsequently replaces a call to the C run-time library version with an inline version. The cc21k compiler contains a number of intrinsic built-in functions for efficient access to various features of the hardware. Built-in functions are recognized for cases where the name begins with the string __builtin, and the declared prototype of the function matches the prototype that the compiler expects. Built-in functions are declared in the builtins.h header file. Include this header file in your program to use these functions. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-35 C and C++ Run-Time Libraries Guide Typically, inline built-in functions are faster than an average library routine, as they do not incur the calling overhead. The routines in Table 1-15 are built-in C library functions for the cc21k compiler. Table 1-15. Compiler Built-in Functions abs avg clip copysignf fabs1 fabsf favg1 favgf fclip1 fclipf fmax1 fmaxf fmin1 fminf labs lavg lclip lmax lmin max memcpy2 memmove2 min strcpy2 strlen2 copysign 1 1 These functions are only compiled as a built-in function if double is the same size as float. 2 Not all references to these functions will be inlined. Some will generate a call to a library function if the compiler does not have sufficient information about the arguments to generate efficient inline code. If you want to use the C run-time library functions of the same name instead of the built-in function, refer to "builtins.h" in the C/C++ Compiler Manual for SHARC Processors. Abridged C++ Library Support When in C++ mode, the cc21k compiler can call a large number of functions from the Abridged Library, a conforming subset of C++ library. The Abridged C++ library has two major components: embedded C++ library (EC++) and embedded standard template library (ESTL). The 1-36 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library embedded C++ library is a conforming implementation of the embedded C++ library as specified by the Embedded C++ Technical Committee. You can view the Abridged Library Reference in the CCES online help. This section lists and briefly describes the following components of the Abridged C++ library: * Embedded C++ Library Header Files * C++ Header Files for C Library Facilities * Embedded Standard Template Library Header Files For more information on the Abridged Library, see online help. Embedded C++ Library Header Files The following section provides a brief description of the header files in the embedded C++ library. complex The complex header file defines a template class complex and a set of associated arithmetic operators. Predefined types include complex_float and complex_long_double. This implementation does not support the full set of complex operations as specified by the C++ standard. In particular, it does not support either the transcendental functions or the I/O operators << and >>. The complex header and the C library header file complex.h refer to two different and incompatible implementations of the complex data type. exception The exception header file defines the exception and bad_exception classes and several functions for exception handling. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-37 C and C++ Run-Time Libraries Guide fstream The fstream header file defines the filebuf, ifstream, and ofstream classes for external file manipulations. iomanip The iomanip header file declares several iostream manipulators. Each manipulator accepts a single argument. ios The ios header file defines several classes and functions for basic iostream manipulations. Note that most of the iostream header files include ios. iosfwd The iosfwd header file declares forward references to various iostream template classes defined in other standard header files. iostream The iostream header file declares most of the iostream objects used for the standard stream manipulations. istream The istream header file defines the istream class for iostream extractions. Note that most of the iostream header files include istream. new The new header file declares several classes and functions for memory allocations and deallocations. ostream The ostream header file defines the ostream class for iostream insertions. 1-38 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library sstream The sstream header file defines the stringbuf, istringstream, and ostringstream classes for various string object manipulations. stdexcept The stdexcept header file defines a variety of classes for exception reporting. streambuf The streambuf header file defines the streambuf classes for basic operations of the iostream classes. Note that most of the iostream header files include streambuf. string The string header file defines the string template and various supporting classes and functions for string manipulations. of the type should not be confused with the Objects null-terminated C strings. string strstream The strstream header file defines the strstreambuf, istrstream, and ostream classes for iostream manipulations on allocated, extended, and freed character sequences. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-39 C and C++ Run-Time Libraries Guide C++ Header Files for C Library Facilities For each C standard library header there is a corresponding standard C++ header. If the name of a C standard library header file were foo.h, then the name of the equivalent C++ header file would be cfoo. For example, the C++ header file provides the same facilities as the C header file . Table 1-16 lists the C++ header files that provide access to the C library facilities. The C standard headers files may be used to define names in the C++ global namespace, while the equivalent C++ header files define names in the standard namespace. Table 1-16. C++ Header Files for C Library Facilities Header Description cassert Enforces assertions during function executions cctype Classifies characters cerrno Tests error codes reported by library functions cfloat Tests floating-point type properties climits Tests integer type properties clocale Adapts to different cultural conventions cmath Provides common mathematical operations csetjmp Executes non-local goto statements csignal Controls various exceptional conditions cstdarg Accesses a variable number of arguments cstddef Defines several useful data types and macros cstdio Performs input and output cstdlib Performs a variety of operations cstring Manipulates several kinds of strings 1-40 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Chapter 2, DSP Run-Time Library describes the functions in the DSP run-time libraries. Referencing these functions with a namespace prefix is not supported. All DSP library functions are in the global namespace. Embedded Standard Template Library Header Files Templates and the associated header files are not part of the embedded C++ standard, but they are supported by the cc21k compiler in C++ mode. The embedded standard template library header files are: algorithm The algorithm header file defines numerous common operations on sequences. deque The deque header file defines a deque template container. functional The functional header file defines numerous function templates that can be used to create callable types. hash_map The hash_map header file defines two hashed map template containers. hash_set The hash_set header file defines two hashed set template containers. iterator The iterator header file defines common iterators and operations on iterators. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-41 C and C++ Run-Time Libraries Guide list The list header file defines a list template container. map The map header file defines two map template containers. memory The memory header file defines facilities for managing memory. numeric The numeric header file defines several numeric operations on sequences. queue The queue header file defines two queue template container adapters. set The set header file defines two set template containers. stack The stack header file defines a stack template container adapter. utility The utility header file defines an assortment of utility templates. vector The vector header file defines a vector template container. 1-42 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Header Files for C++ Library Compatibility The Embedded C++ library also includes several header files for compatibility with traditional C++ libraries. Table 1-17 describes these files. Table 1-17. Header Files for C++ Library Compatibility Header Description fstream.h Defines several iostream template classes that manipulate external files iomanip.h Declares several iostreams manipulators that take a single argument iostream.h Declares the iostream objects that manipulate the standard streams new.h Declares several functions that allocate and free storage Measuring Cycle Counts The common basis for benchmarking some arbitrary C-written source is to measure the number of processor cycles that the code uses. Once this figure is known, it can be used to calculate the actual time taken by multiplying the number of processor cycles by the clock rate of the processor. The run-time library provides three alternative methods for measuring processor cycles, as described in the following sections. Each of these methods is described in: * Basic Cycle Counting Facility * Cycle Counting Facility With Statistics * Using time.h to Measure Cycle Counts * Determining the Processor Clock Rate * Considerations When Measuring Cycle Counts CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-43 C and C++ Run-Time Libraries Guide Basic Cycle Counting Facility The fundamental approach to measuring the performance of a section of code is to record the current value of the cycle count register before executing the section of code, and then reading the register again after the code has been executed. This process is represented by two macros that are defined in the cycle_count.h header file: START_CYCLE_COUNT(S) STOP_CYCLE_COUNT(T,S) The parameter S is set by the macro START_CYCLE_COUNT to the current value of the cycle count register; this value should then be passed to the macro STOP_CYCLE_COUNT, which will calculate the difference between the parameter and current value of the cycle count register. Reading the cycle count register incurs an overhead of a small number of cycles and the macro ensures that the difference returned (in the parameter T) will be adjusted to allow for this additional cost. The parameters S and T should be separate variables. They should be declared as a cycle_t data type that the header file cycle_count.h defines as: typedef volatile unsigned long cycle_t; The type can be configured to use the type for its definition. To do this, you should compile your applicycle_t unsigned long long cation with the compile-time macro __LONG_LONG_PROCESSOR_TIME__ defined to 1. The header file also defines the macro: PRINT_CYCLES(STRING,T) which is provided mainly as an example of how to print a value of type cycle_t; the macro outputs the text STRING on stdout followed by the number of cycles T. 1-44 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library The instrumentation represented by the macros defined in this section is activated only if the program is compiled with the -DDO_CYCLE_COUNTS switch. If this switch is not specified, then the macros are replaced by empty statements and have no effect on the program. The following example demonstrates how the basic cycle counting facility may be used to monitor the performance of a section of code: #include #include extern int main(void) { cycle_t start_count; cycle_t final_count; START_CYCLE_COUNT(start_count); Some_Function_Or_Code_To_Measure(); STOP_CYCLE_COUNT(final_count,start_count); PRINT_CYCLES("Number of cycles: ",final_count); } The run-time libraries provide alternative facilities for measuring the performance of C source (see Cycle Counting Facility With Statistics and Using time.h to Measure Cycle Counts); the relative benefits of this facility are outlined in Considerations When Measuring Cycle Counts. The basic cycle counting facility is based upon macros; it may therefore be customized for a particular application (if required), without the need for rebuilding the run-time libraries. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-45 C and C++ Run-Time Libraries Guide Cycle Counting Facility With Statistics The cycles.h header file defines a set of macros for measuring the performance of compiled C source. In addition to providing the basic facility for reading the EMUCLK cycle count register of the SHARC architecture, the macros can also accumulate statistics suited to recording the performance of a section of code that is executed repeatedly. If the switch -DDO_CYCLE_COUNTS is specified at compile-time, the cycles.h header file defines the following macros: * CYCLES_INIT(S) This macro initializes the system timing mechanism and clears the parameter S; an application must contain one reference to this macro. * CYCLES_START(S) This macro extracts the current value of the cycle count register and saves it in the parameter S. * CYCLES_STOP(S) This macro extracts the current value of the cycle count register and accumulates statistics in the parameter S, based on the previous reference to the CYCLES_START macro. * CYCLES_PRINT(S) This macro prints a summary of the accumulated statistics recorded in the parameter S. * CYCLES_RESET(S) This macro re-zeros the accumulated statistics that are recorded in the parameter S. The parameter S that is passed to the macros must be declared to be of the type cycle_stats_t; this is a structured data type that is defined in the cycles.h header file. The data type can record the number of times that an instrumented part of the source has been executed, as well as the 1-46 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library minimum, maximum, and average number of cycles that have been used. For example, if an instrumented piece of code has been executed 4 times, the CYCLES_PRINT macro would generate output on the standard stream stdout in the form: AVG : 95 MIN : 92 MAX : 100 CALLS : 4 If an instrumented piece of code had only been executed once, then the CYCLES_PRINT macro would print a message of the form: CYCLES : 95 If the switch -DDO_CYCLE_COUNTS is not specified, then the macros described above are defined as null macros and no cycle count information is gathered. Therefore, to switch between development and release mode only requires a re-compilation and will not require any changes to the source of an application. The macros defined in the cycles.h header file may be customized for a particular application without having to rebuild the run-time libraries. The following example demonstrates how this facility may be used. #include #include extern void foo(void); extern void bar(void); extern int main(void) { cycle_stats_t stats; int i; CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-47 C and C++ Run-Time Libraries Guide CYCLES_INIT(stats); for (i = 0; i < LIMIT; i++) { CYCLES_START(stats); foo(); CYCLES_STOP(stats); } printf("Cycles used by foo\n"); CYCLES_PRINT(stats); CYCLES_RESET(stats); CYCLES_START(stats); bar(); CYCLES_STOP(stats); } printf("Cycles used by bar\n"); CYCLES_PRINT(stats); } This example might output: Cycles used by foo AVG : 25454 MIN : 23003 MAX : 26295 CALLS : 16 Cycles used by bar AVG : 8727 MIN : 7653 MAX : 8912 CALLS : 16 1-48 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Alterative methods of measuring the performance of compiled C source are described in the sections Basic Cycle Counting Facility and Using time.h to Measure Cycle Counts. Also refer to Considerations When Measuring Cycle Counts which provides some useful tips with regards to performance measurements. Using time.h to Measure Cycle Counts The time.h header file defines the data type clock_t, the clock function, and the macro CLOCKS_PER_SEC, which together may be used to calculate the number of seconds spent in a program. In the ANSI C standard, the clock function is defined to return the number of implementation dependent clock "ticks" that have elapsed since the program began. In this version of the C/C++ compiler, the function returns the number of processor cycles that an application has used. The conventional way of using the facilities of the time.h header file to measure the time spent in a program is to call the clock function at the start of a program, and then subtract this value from the value returned by a subsequent call to the function. The computed difference is usually cast to a floating-point type, and is then divided by the macro CLOCKS_PER_SEC to determine the time in seconds that has occurred between the two calls. If this method of timing is used by an application, note that: * The value assigned to the macro CLOCKS_PER_SEC should be independently verified to ensure that it is correct for the particular processor being used (see Determining the Processor Clock Rate), * The result returned by the clock function does not include the overhead of calling the library function. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-49 C and C++ Run-Time Libraries Guide A typical example that demonstrates the use of the time.h header file to measure the amount of time that an application takes is shown below. #include #include extern int main(void) { volatile clock_t clock_start; volatile clock_t clock_stop; double secs; clock_start = clock(); Some_Function_Or_Code_To_Measure(); clock_stop = clock(); secs = ((double) (clock_stop - clock_start)) / CLOCKS_PER_SEC; printf("Time taken is %e seconds\n",secs); } The cycles.h and cycle_count.h header files define other methods for benchmarking an application--these header files are described in the sections Basic Cycle Counting Facility and Cycle Counting Facility With Statistics, respectively. Also refer to Considerations When Measuring Cycle Counts which provides some guidelines that may be useful. Determining the Processor Clock Rate Applications may be benchmarked with respect to how many processor cycles they use. However, applications are typically benchmarked with respect to how much time (for example, in seconds) that they take. 1-50 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Measuring the amount of time that an application takes to run on a SHARC processor usually involves first determining the number of cycles that the processor takes, and then dividing this value by the processor's clock rate. The time.h header file defines the macro CLOCKS_PER_SEC as the number of processor "ticks" per second. On an ADSP-21xxx (SHARC) architecture, this parameter is set by the run-time library to one of the following values in descending order of precedence: * By way of the compile-time switch: -DCLOCKS_PER_SEC= * By way of Project > Properties > C/C++ Build > Settings > Compiler > Processor > Processor speed (MHz) * From the cycles.h header file If the value of the macro CLOCKS_PER_SEC is taken from the cycles.h header file, then be aware that the clock rate of the processor will usually be taken to be the maximum speed of the processor, which is not necessarily the speed of the processor at RESET. Considerations When Measuring Cycle Counts This section summarizes cycle-counting techniques for benchmarking C-compiled code. Each of these alternatives are described below. * Basic Cycle Counting Facility The basic cycle counting facility represents an inexpensive and relatively unobtrusive method for benchmarking C-written source using cycle counts. The facility is based on macros that factor in the overhead incurred by the instrumentation. The macros may be customized and can be switched either or off, and so no source CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-51 C and C++ Run-Time Libraries Guide changes are required when moving between development and release mode. The same set of macros is available on other platforms provided by Analog Devices. * Cycle Counting Facility With Statistics This cycle-counting facility has more features than the basic cycle counting facility described above. It is more expensive in terms of program memory, data memory, and cycles consumed. However, it can record the number of times that the instrumented code has been executed and can calculate the maximum, minimum, and average cost of each iteration. The provided macros take into account the overhead involved in reading the cycle count register. By default, the macros are switched off, but they can be switched on by specifying the -DDO_CYCLE_COUNTS compile-time switch. The macros may be customized for a specific application. This cycle counting facility is also available on other Analog Devices architectures. * Using time.h to Measure Cycle Counts The facilities of the time.h header file represent a simple method for measuring the performance of an application that is portable across many different architectures and systems. These facilities are based on the clock function. The clock function however does not account for the cost involved in invoking the function. In addition, references to the function may affect the optimizer-generated code in the vicinity of the function call. This benchmarking method may not accurately reflect the true cost of the code being measured. This method is best suited for benchmarking applications rather than smaller sections of code that run for a much shorter time span. 1-52 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library When benchmarking code, some thought is required when adding instrumentation to C source that will be optimized. If the sequence of statements to be measured is not selected carefully, the optimizer may move instructions into (and out of) the code region and/or it may re-site the instrumentation itself, leading to distorted measurements. Therefore, it is generally considered more reliable to measure the cycle count of calling (and returning from) a function rather than a sequence of statements within a function. It is recommended that variables used directly in benchmarking are simple scalars that are allocated in internal memory (either assigned the result of a reference to the clock function, or used as arguments to the cycle counting macros). In the case of variables that are assigned the result of the clock function, it is also recommended that they be defined with the volatile keyword. The different methods presented here to obtain the performance metrics of an application are based on the EMUCLK register. This is a 32-bit register that is incremented at every processor cycle; once the counter reaches the value 0xffffffff it will wrap back to zero and will also increment the EMUCLK2 register. By default, to save memory and execution time, the EMUCLK2 register is not used by either the clock function or the cycle counting macros. The performance metrics therefore will wrap back to zero after approximately every 71 seconds on a 60 MHz processor. If you require a longer measurement duration, define the compile-time macro __LONG_LONG_PROCESSOR_TIME__. File I/O Support The CCES environment provides access to files on a host system by using stdio functions. File I/O support is provided through a set of low-level primitives that implement the open, close, read, write, and seek operations, among others. The functions defined in the stdio.h header file make use of these primitives to provide conventional C input and output CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-53 C and C++ Run-Time Libraries Guide facilities. For details on File I/O support, refer to the system run-time documentation. Refer to stdio.h for information about the conventional C input and output facilities that are provided by the compiler. Fatal Error Handling The CCES run-time library provides a global mechanism for handling non-recoverable, or fatal, errors encountered during application execution. This is provided by the functions adi_fatal_error and adi_fatal_exception, which write information related to the encountered error before looping around the breakpoints __fatal_error and __fatal_exception. Four items of information can be stored regarding the encountered error: * General code indicating the source of the error * Specific code indicating the actual error that occurred * A PC address indicating where the error was reported * A value related to the error. This may not be relevant and may be left empty. This information is stored in global variables detailed in Table 1-18. Each variable is 32 bits in size. The value related to the error can be interpreted in different ways, depending on the error it is associated with. 1-54 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Table 1-18. Global Variables Used In Fatal Error Reporting Use Label Type General code __adi_fatal_error_general_code integer Specific code __adi_fatal_error_specific_code integer PC __adi_fatal_error_pc memory address Value __adi_fatal_error_value depends on error FatalError.xml FatalError.xml, contained in the System directory of the CCES installation, details the relationships between general codes and specific codes, as well as providing additional detail on the specific code such as a description of the error. A general code is associated with a list of specific codes, though a list of specific codes can be associated with one or more general codes. Specific code values must be unique within a list of specific codes, but duplicate specific codes are allowed if they are within separate lists. General Codes is a general code associated with the run-time libraries. It refers to errors identified with the use of the run-time libraries. An additional general code, UserError, is available for any user-defined error values. The values representing these codes are shown in Table 1-19. LibraryError Table 1-19. General Error Codes Used By Run-Time Library General Code Name Value Run-time Library error LibraryError 0x7 Errno values Errno 0xB User defined error UserError 0xffffffff CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-55 C and C++ Run-Time Libraries Guide Library Error Specific Codes The specific code list associated with the LibraryError general code details any fatal errors that may be identified by use of the run-time libraries. These errors are described in Table 1-20. Table 1-20. Library Error Specific Codes Specific Error Code Value Description 0x2 InsufficientHeapForLibrary An allocation from the default None heap in the system libraries has failed. 0x3 IONotAllowed I/O has been requested when scheduling has been disabled, or from within an ISR. 0x4 ProfBadExeName Profiling/heap debugging has None failed due to an invalid application filename. 0x5 OSAL BindingError An operating system abstraction layer function has failed. None 0x6 adi_osal_Init_failure The call to adi_osal_Init made from the CRT startup code returned an error. None 0x101 HeapUnknown An unknown heap debugging error has occurred. None 0x102 HeapFailed A heap operation has failed. None 0x103 HeapAllocationOfZero A heap allocation of zero has been detected. None 0x104 HeapNullPointer A heap operation using an unexpected null pointer has been detected. None 0x105 HeapInvalidAddress A heap operation using an invalid address has been detected. Pointer to invalid address 1-56 Error Value Interpretation None CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Table 1-20. Library Error Specific Codes (Cont'd) Specific Error Code Value Description Error Value Interpretation 0x106 HeapBlockIsCorrupt A corrupt block has been detected on the heap. Pointer to corrupt block 0x107 HeapReallocOfZero A call to realloc with no pointer None or size has been detected. 0x108 HeapFunctionMisMatch A heap operation incompatible Pointer to with the block being manipu- block being lated has been detected. manipulated 0x109 HeapUnfreedBlock An unfreed block on the heap has been detected. Pointer to unfreed block 0x10a HeapWrongHeap A heap operation using the wrong heap has been detected. Pointer to block being manipulated 0x10b HeapAllocationTooLarge A heap allocation request larger None than the heap that it is being allocated to has been detected. 0x10c HeapInvalidInput A heap operation has been given an invalid input. None 0x10d HeapInternalError An internal error has occurred within the heap debugging library. None 0x10e HeapInInterrupt The heap has been used within None an interrupt. 0x10f HeapMissingOutput There is output missing from the heap report file, due to insufficient buffering. 0x110 HeapInsufficientSpace Heap debugging has failed, due None to insufficient available heap space. 0x111 HeapCantOpenDump Heap debugging cannot open heap dump file. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Unsigned integer counting number of missing 8-bit bytes None 1-57 Documented Library Functions Table 1-20. Library Error Specific Codes (Cont'd) Specific Error Code Value Description Error Value Interpretation 0x112 HeapCantOpenTrace Heap debugging cannot open .hpl file for report output. None 0x113 HeapInvalidHeapID An invalid heap id has been used. Id of invalid heap 0x201 InstrprofIOFail Instrumented profiling cannot open its output file. None 0x301 PGOHWFailedOutput The PGO on hardware None run-time support failed to open an output file. 0x302 PGOHWDataCorrupted An internal error has occurred in the PGO on hardware run-time support. None 0x303 PGOHWInvalidPGO The existing PGO data file appears to be corrupted. None Errno Values The specific codes for the Errno general code map directly onto the errno variable itself. Refer to errno.h for interpretation of the values. Documented Library Functions The C run-time library has several categories of functions and macros defined by the ANSI C standard, plus extensions provided by Analog Devices. The following tables list the library functions documented in this chapter. Note that the tables list the functions for each header file separately; however, the reference pages for these library functions present the functions in alphabetical order. 1-58 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Table 1-21 lists the library functions in the ctype.h header file. Refer to ctype.h for more information on this header file. Table 1-21. Library Functions in the ctype.h Header File isalnum isalpha iscntrl isdigit isgraph islower isprint ispunct isspace isupper isxdigit tolower toupper Table 1-22 lists the library functions in the heap_debug.h header file. Refer to heap_debug.h for more information on this header file. Table 1-22. Library Functions in the heap_debug.h Header File adi_dump_all_heaps adi_dump_heap adi_heap_debug_disable adi_heap_debug_enable adi_heap_debug_end adi_heap_debug_flush adi_heap_debug_pause adi_heap_debug_reset_guard_region adi_heap_debug_resume adi_heap_debug_set_buffer adi_heap_debug_set_call_stack_depth adi_heap_debug_set_error adi_heap_debug_set_guard_region adi_heap_debug_set_ignore adi_heap_debug_set_warning adi_verify_all_heaps adi_verify_heap CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-59 Documented Library Functions Table 1-23 lists functions in the libdyn.h header file. For more information, see libdyn.h. Table 1-23. Library Functions in the libdyn.h Header File dyn_AddHeap dyn_alloc dyn_AllocSectionMem dyn_AllocSectionMemHeap dyn_CopySectionContents dyn_FreeEntryPointArray dyn_FreeSectionMem dyn_GetEntryPointArray dyn_GetExpSymTab dyn_GetHeapForWidth dyn_GetNumSections dyn_GetSections dyn_GetStringTable dyn_GetStringTableSize dyn_heap_init dyn_LookupByName dyn_RecordRelocOutOfRange dyn_Relocate dyn_RetrieveRelocOutOfRange dyn_RewriteImageToFile dyn_SetSectionAddr dyn_SetSectionMem dyn_ValidateImage Table 1-24 lists the library functions in the locale.h header file. Refer to locale.h for more information on this header file. Table 1-24. Library Functions in the locale.h Header File localeconv setlocale Table 1-25 lists the library functions in the math.h header file. Refer to math.h for more information on this header file. Table 1-25. Library Functions in the math.h Header File acos asin atan atan2 ceil cos cosh exp fabs floor fmod frexp isinf isnan ldexp log log10 modf 1-60 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Table 1-25. Library Functions in the math.h Header File (Cont'd) pow sin sinh sqrt tan tanh Table 1-26 lists the library functions in the setjmp.h header file. Refer to setjmp.h for more information on this header file. Table 1-26. Library Functions in the setjmp.h Header File longjmp setjmp Table 1-27 lists the library functions in the signal.h header file. Refer to signal.h for more information on this header file. Table 1-27. Library Functions in the signal.h Header File raise signal Table 1-28 lists the library functions in the stdarg.h header file. Refer to stdarg.h for more information on this header file. Table 1-28. Library Functions in the stdarg.h Header File va_arg va_end CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors va_start 1-61 Documented Library Functions Table 1-29 lists the library functions in the stdfix.h header file. Refer to stdfix.h for more information on this header file. Table 1-29. Library Functions in the stdfix.h Header File absfx bitsfx countlsfx divifx fxbits fxdivi idivfx mulifx roundfx strtofxfx Table 1-30 lists the library functions in the stdio.h header file. Refer to stdio.h for more information on this header file. Table 1-30. Library Functions in the stdio.h Header File clearerr fclose feof ferror fflush fgetc fgetpos fgets fileno fopen fprintf fputc fputs fread freopen fscanf fseek fsetpos ftell fwrite getc getchar gets ioctl perror printf putc putchar puts remove rename rewind scanf setbuf setvbuf snprintf sprintf sscanf ungetc vfprintf vprintf vsnprintf vsprintf 1-62 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Table 1-24 lists the library functions in the stdlib.h header file. Refer to stdlib.h for more information on this header file. Table 1-31. Library Functions in the stdlib.h Header File abort abs adi_fatal_error adi_fatal_exception atexit atof atoi atol atold atoll avg bsearch calloc clip count_ones div exit free getenv heap_calloc heap_free heap_init heap_install heap_lookup heap_malloc heap_realloc heap_space_unused heap_switch labs lavg lclip lcount_ones ldiv llabs llavg llclip llcount_ones lldiv llmax llmin lmax lmin malloc max min qsort rand realloc space_unused srand strtod strtol strtoll strtold strtoul strtoull system CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-63 Documented Library Functions Table 1-32 lists the library functions in the string.h header file. Refer to string.h for more information on this header file. Table 1-32. Library Functions in the string.h Header File memchr memcmp memcpy memmove memset strcat strchr strcmp strcoll strcpy strcspn strerror strlen strncat strncmp strncpy strpbrk strrchr strspn strstr strtok strxfrm Table 1-33 lists the library functions in the time.h header file. Refer to time.h for more information on this header file. Table 1-33. Library Functions in the time.h Header File asctime clock ctime difftime gmtime localtime mktime strftime time 1-64 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library C Run-Time Library Reference The C run-time library is a collection of functions that you can call from your C/C++ programs. This section lists the functions in alphabetical order. Notation Conventions An interval of numbers is indicated by the minimum and maximum, separated by a comma, and enclosed in two square brackets, two parentheses, or one of each. A square bracket indicates that the endpoint is included in the set of numbers; a parenthesis indicates that the endpoint is not included. Reference Format Each function in the library has a reference page. These pages have the following format: Name and purpose of the function Synopsis - Required header file and functional prototype Description - Function specification Error Conditions - Method that the functions use to indicate an error Example -Typical function usage See Also - Related functions CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-65 Documented Library Functions abort Abnormal program end Synopsis #include void abort (void); Description The abort function causes an abnormal program termination by raising the SIGABRT exception. If the SIGABRT handler returns, abort() calls _Exit() to terminate the program. Error Conditions None. Example #include extern int errors; if (errors) abort(); /* terminate program if */ /* errors are present */ See Also raise, signal 1-66 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library abs Absolute value Synopsis #include int abs (int j); Description The abs function returns the absolute value of its integer argument. Note: abs(INT_MIN) returns INT_MIN. Error Conditions None. Example #include int i; i = abs (-5); /* i == 5 */ See Also fabs, absfx, labs, llabs CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-67 Documented Library Functions absfx absolute value Synopsis #include short fract abshr(short fract f); fract absr(fract f); long fract abslr(long fract f); Description The absfx family of functions return the absolute value of their fixed-point input. In addition to the individually-named functions for each fixed-point type, a type-generic macro absfx is defined for use in C99 mode. This may be used with any of the fixed-point types and returns a result of the same type as its operand. Error Conditions None. Example #include long fract f; f = abslr(0.75lr); /* f == 0.75lr */ f = absfx(0.75lr); /* f == 0.75lr */ See Also abs, fabs, labs, llabs 1-68 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library acos Arc cosine Synopsis #include float acosf (float x); double acos (double x); long double acosd (long double x); Description The arc cosine functions return the arc cosine of x. The input must be in the range [-1, 1]. The output, in radians, is in the range [0, ]. Error Conditions The arc cosine functions indicate a domain error (set errno to EDOM) and return a zero if the input is not in the range [-1, 1]. Example #include double x; float y; x = acos (0.0); /* x = /2 */ y = acosf (0.0); /* y = /2 */ See Also cos CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-69 Documented Library Functions adi_dump_all_heaps Dump the current state of current heaps to a file Synopsis #include void adi_dump_all_heaps(char *filename); Description The adi_dump_all_heaps function writes the current state of all of the heaps known to the heap debugging library to the file specified by filename. The information written to the file consists of the address, size and state of any blocks on that heap that have been tracked by the heap debugging library, and the total memory currently allocated from that heap. If the specified file exists, then the file is appended to; otherwise, a new file is created. adi_dump_all_heaps function relies on the heap usage being The tracked by the heap debugging library, any heap activity which is carried out when heap usage is not being tracked (when heap debugging is paused or disabled) will not be included in the output. The adi_heap_dump_all_heaps should be called only when it is safe to carry out I/O operations. Calling adi_adi_dump_all_heaps from within an interrupt or an unscheduled region will result in adi_fatal_error being called. For more information on heap debugging, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. 1-70 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Error Conditions The adi_dump_heap function calls adi_fatal_error if it is unable to open the requested file. Example #include #include void dump_heaps() { adi_dump_all_heaps("./dumpfile.txt"); } See Also adi_dump_heap, adi_fatal_error CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-71 Documented Library Functions adi_dump_heap Dump the current state of a heap to a file Synopsis #include bool adi_dump_heap(char *filename, int heapindex); Description The adi_dump_heap function writes the current state of the heap identified by heapindex to the file specified by filename. The information written to the file consists of the address, size and state of any blocks on that heap tracked by the heap debugging library, and the total memory currently allocated from that heap. If the specified file exists, then the file is appended to, otherwise a new file is created. adi_dump_heap function relies on the heap usage being The tracked by the heap debugging library. Any heap activity which is carried out when heap usage is not being tracked (when heap debugging is paused or disabled) will not be included in the output. The adi_heap_dump_heap function should be called only when it is safe to carry out I/O operations. Calling adi_adi_dump_heap from within an interrupt or an unscheduled region will result in adi_fatal_error being called For more information on heap debugging, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. 1-72 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Error Conditions The adi_dump_heap function calls adi_fatal_error if it is unable to open the requested file. Example #include #include void dump_heap(int heapindex) { if (!adi_dump_heap("./dumpfile.txt", heapindex)) { printf("heap %d does not exist\n", heapindex); } } See Also adi_dump_all_heaps, adi_fatal_error CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-73 Documented Library Functions adi_fatal_error Handle a non-recoverable error Synopsis #include void adi_fatal_error(int general_code, int specific_code, int value); Description The adi_fatal_error function handles a non-recoverable error. The parameters general_code,specific_code and value will be written to global variables along with the return address, before looping around the label __fatal_error. The adi_fatal_error function can be jumped to rather than called in order to preserve the return address if required. See Fatal Error Handling for more information. Error Conditions None. Example #include #define MY_GENERAL_CODE (0x9) void non_recoverable_error(int code, int value) { adi_fatal_error(MY_GENERAL_CODE, code, value); } 1-74 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also adi_fatal_exception CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-75 Documented Library Functions adi_fatal_exception Handle a non-recoverable exception Synopsis #include void adi_fatal_exception(int general_code, int specific_code, int value); Description The adi_fatal_exception function handles a non-recoverable exception. The parameters general_code, specific_code and value will be written to global variables along with the return address, before looping around the label __fatal_exception. The adi_fatal_exception function can be jumped to rather than called in order to preserve the return address if required. See Fatal Error Handling for more information. Error Conditions None. Example #include #define MY_GENERAL_CODE (0x9) void non_recoverable_exception(int code, int value) { adi_fatal_exception(MY_GENERAL_CODE, code, value); } 1-76 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also adi_fatal_error CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-77 Documented Library Functions adi_heap_debug_disable Disable features of the heap debugging Synopsis #include void adi_heap_debug_disable(unsigned char flag); Description The adi_heap_debug_disable function accepts a bit-field parameter detailing which features are to be enabled. These bits are represented by macros defined in heap_debug.h. These parameter bits can be combined using the bitwise OR operator to allow multiple settings to be disabled at once. For more information on heap debugging, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions None. Example #include void disable_diagnostics() { // Disable run-time errors adi_heap_debug_disable(_HEAP_STDERR_DIAG); } 1-78 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also adi_heap_debug_enable CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-79 Documented Library Functions adi_heap_debug_enable Enable features of the heap debugging Synopsis #include void adi_heap_debug_enable(unsigned char flag); Description The adi_heap_debug_enable function accepts a bit-field parameter detailing which features are to be enabled. These bits are represented by macros defined in heap_debug.h. _HEAP_TRACK_USAGE (track heap activity) is implicitly enabled when either _HEAP_STDERR_DIAG (generate diagnostics at runtime) or _HEAP_HPL_GEN (generate .hpl file of heap activity used by report) are enabled. These parameter bits can be combined using the bitwise OR operator to allow multiple settings to be enabled at once. For more information on heap debugging, see section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions None. Example #include void enable_hpl_gen() { // Enable run-time errors and the generation of the .hpl file adi_heap_debug_enable(_HEAP_STDERR_DIAG | _HEAP_HPL_GEN); } 1-80 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also adi_heap_debug_disable CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-81 Documented Library Functions adi_heap_debug_end Finish heap debugging Synopsis #include void adi_heap_debug_end(void); Description The adi_heap_debug_end function records the end of the heap debugging. Internal data used by the heap debugging library will be freed, the .hpl file generated will be closed (if .hpl generation is enabled) and any heap corruption or memory leaks will be reported. The adi_heap_debug_end function can be called multiple times, allowing heap debugging to be started and ended over specific sections of code. Use adi_heap_debug_end in non-terminating applications to instruct the heap debugging library to carry out the end checks for the heap debugging in that application. Do not call adi_heap_debug_end from within an ISR or when thread switching as there will be no way for it to produce any output. For more information on heap debugging, see section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions Corrupt blocks or memory leaks may be reported via the console view (if run-time diagnostics are enabled) or via the report (if .hpl file generation is enabled). 1-82 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Example #include void main_func() { // Start heap debugging adi_heap_debug_enable(_HEAP_STDERR_DIAG); // Application code run_application(); // Check for leaks or corruption adi_heap_debug_end(); } See Also adi_heap_debug_enable CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-83 Documented Library Functions adi_heap_debug_flush Flush the heap debugging output buffer Synopsis #include void adi_heap_debug_flush(void); Description The adi_heap_debug_flush function flushes any buffered data to the .hpl file used by the reporter tool to generated the heap debugging report. adi_heap_debug_flush function should only be called when it The is safe to carry out I/O operations. Calling adi_heap_debug_flush from within an interrupt or an unscheduled region will result in adi_fatal_error being called. For more information on heap debugging, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions The adi_heap_debug_flush function calls adi_fatal_error if called when it is unsafe to use I/O. Example #include void flush_hpl_buffer() { adi_heap_debug_flush(); } 1-84 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also adi_fatal_error CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-85 Documented Library Functions adi_heap_debug_pause Temporarily disable the heap debugging Synopsis #include void adi_heap_debug_pause(void); Description The adi_heap_debug_pause function disables the heap debugging functionality. When disabled, the heap debugging library has a minimal performance overhead compared to the non-debug versions of the heap debugging functions provided by the C/C++ run-time libraries. Pausing heap debugging means that any heap operations, which happen between pausing and re-enabling the heap debugging, will not be tracked, meaning that erroneous behavior may not be detected and false errors regarding unfreed blocks or unknown addresses may be reported. Take care when using adi_heap_debug_pause in a threaded environment, as the heap debugging will be disabled globally rather than within the context of the current thread. For more information on heap debugging, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions None. 1-86 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Example #include void a_performance_critical_function(void); void performance_critical_fn_wrapper() { adi_heap_debug_pause(); a_performance_critical_function(); adi_heap_debug_resume(); } See Also adi_heap_debug_resume CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-87 Documented Library Functions adi_heap_debug_reset_guard_region Reset guard regions to default values Synopsis #include bool adi_heap_debug_reset_guard_region(void); Description The adi_heap_debug_reset_guard_region function resets the guard region values to the default. The heaps are checked for guard region corruption before all existing guard regions are replaced with the new values. If corruption is detected, then no guard regions are changed and adi_heap_debug_reset_guard_region returns false. The contents of existing allocated blocks are not changed, but any newly allocated blocks are pre-filled with the new allocated block pattern. The default reset values are detailed in Table 1-34. Table 1-34. Reset Values for Heap Guard Regions Region Value Free block 0xBDBDBDBD Allocated block 0xDDDDDDDD Block content (not calloc) 0xEDEDEDED For more information on heap debugging, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions The adi_heap_debug_reset_guard_region function returns false if no guard region change was made, due to the detection of corruption on one of the heaps. 1-88 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Example #include #include void reset_guard_region() { if (!adi_heap_debug_reset_guard_region()) { printf("couldn't reset guard regions\n"); } } See Also adi_heap_debug_set_guard_region CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-89 Documented Library Functions adi_heap_debug_resume Re-enable the heap debugging Synopsis #include void adi_heap_debug_resume(void); Description The adi_heap_debug_resume function enables the heap debugging. Any allocations or de-allocations that occurred when the heap debugging was disabled will not have been tracked by the heap debugging library, so false errors regarding invalid addresses or memory leaks may be produced. For more information on heap debugging, see section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions None. Example #include void a_performance_critical_function(void); void performance_critical_fn_wrapper() { adi_heap_debug_pause(); a_performance_critical_function(); adi_heap_debug_resume(); } 1-90 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also adi_heap_debug_pause CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-91 Documented Library Functions adi_heap_debug_set_buffer Configure a buffer to be used by the heap debugging Synopsis #include bool adi_heap_debug_set_buffer(void *ptr, size_t size, size_t threshold); Description The adi_heap_debug_set_buffer function instructs the heap debugging library to use the specified buffer for the writing of the .hpl file used by the Reporter Tool to generate a heap debugging report. The buffer is of size addressable units starting at address ptr, with a flush threshold of threshold addressable units. The minimum size of the buffer in addressable units can be determined using the macro _ADI_HEAP_MIN_BUFFER (defined in heap_debug.h) and represents the memory required to store two entries of the heap debugging buffer along with associated call stacks. Changing the call stack depth after setting a buffer may alter the number of entries which can be held within the buffer. Buffering can be disabled by calling adi_heap_debug_set_buffer with a null pointer as the first parameter. Using a buffer will reduce the number of I/O operations to write the .hpl file to the host which should in turn result in a significant reduction in execution time when running applications which make frequent use of the heap. If the buffer is full or no buffer is specified, and heap activity occurs where I/O is not permitted, that data will be lost. The buffer will be flushed automatically when it is filled beyond a capacity threshold, specified by the threshold parameter, and it is safe to flush. Flushing can be triggered manually by calling adi_heap_debug_flush. 1-92 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library For more information on heap debugging, see "Heap Debugging" in the C/C++ Compiler Manual for SHARC Processors. call Only I/O operations. Calling when it is safe to carry out adi_heap_debug_set_buffer from within an interrupt or an unscheduled region will result in adi_fatal_error being called. adi_heap_debug_set_buffer Error Conditions The adi_heap_debug_set_buffer function returns false if the buffer passed is not valid or big enough to be used the heap debugging library. Example #include char heapbuffer[1024]; bool set_buffer(void) { if (sizeof(heapbuffer) < _ADI_HEAP_MIN_BUFFER) { return false; } return adi_heap_debug_set_buffer(&heapbuffer, sizeof(heapbuffer), sizeof(heapbuffer)/2); } CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-93 Documented Library Functions adi_heap_debug_set_call_stack_depth Change the depth of the call stack recorded by the heap debugging library Synopsis #include bool adi_heap_debug_set_call_stack_depth(unsigned int depth); Description The adi_heap_debug_set_call_stack_depth function sets the maximum depth of the call stack recorded by the heap debugging library for use in the heap reports and diagnostic messages. The memory for the call stack is allocated from the system heap and requires memory of size (2*sizeof(int)) per call stack element. The default value is 5 stack elements deep. The adi_heap_debug_set_call_stack_depth function returns true if it is able to change the depth; otherwise, false is returned and the depth remains unchanged. For more information on heap debugging, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions The adi_heap_debug_set_call_stack_depth function returns false if it is unable to allocate sufficient memory for the new call stack. 1-94 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Example #include #include bool set_call_stack_depth(unsigned int size) { if (!adi_heap_debug_set_call_stack_depth(size)) { printf("unable to set heap debug call stack " "to %d elements\n", size); return false; } return true; } See Also No related functions. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-95 Documented Library Functions adi_heap_debug_set_error Change error types to be regarded as terminating errors Synopsis #include void adi_heap_debug_set_error(unsigned long flag); Description The adi_heap_debug_set_error function changes the severity of the specified types of heap error to a terminating run-time error. These types are represented as a bit-field using macros defined in heap_debug.h. Terminating run-time errors print a diagnostic message to stderr before calling adi_fatal_error. errors need to be enabled for these changes to have any Run-time effect. For more information on heap debugging, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions None. Example #include void set_errors() { /* Enable run-time diagnostics */ adi_heap_debug_enable(_HEAP_STDERR_DIAG); 1-96 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library /* Regard frees from the wrong heap or of null pointers */ /* as terminating run-time errors */ adi_heap_debug_set_error(_HEAP_ERROR_WRONG_HEAP | _HEAP_ERROR_NULL_PTR ); } See Also adi_heap_debug_enable, adi_heap_debug_set_ignore, adi_heap_debug_set_warning CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-97 Documented Library Functions adi_heap_debug_set_guard_region Changes the bit patterns written to guard regions around memory blocks Synopsis #include bool adi_heap_debug_set_guard_region(unsigned char free, unsigned char allocated, unsigned char content); Description The adi_heap_debug_set_guard_region function changes the bit pattern written to the guard regions around memory blocks used by the heap debugging library to check, if overwriting has occurred. The heaps are checked for guard region corruption before changing the guard regions. If any guard region is corrupt then adi_heap_debug_set_guard_region fails and the guard regions will not be changed. The contents of existing allocations are not be changed, but any new allocations will be pre-filled with the pattern specified by the allocated parameter. The value of free is written to any free blocks, as well as the following guard region. Corruption of these blocks indicates that a pointer has been used to write to a block after it has been freed. The value of allocated is written to the guard regions on either side of the allocated block. Corruption of these blocks indicates that overflow or underflow of that allocation has occurred. The value of content is written to the allocated memory block, with the exception of memory allocated by calloc, which is zero filled. Seeing this value in live data indicates that memory allocated from the heap is used before being initialized. 1-98 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library The current values for the guard regions for free blocks, allocated blocks, and the pattern used for allocated block contents are stored in the "C" char variables adi_heap_guard_free, adi_heap_guard_alloc, and adi_heap_guard_content. These variables can be defined at build-time but should not be written to directly at run-time or false corruption errors may be reported. The guard region values can be reset to the ADI default values by calling adi_heap_debug_reset_guard_region. For more information on heap debugging, see "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions The adi_heap_debug_set_guard_region function returns false if it was unable to change the guard regions, due the presence of block corruption on one of the heaps. Example #include #include bool set_guard_regions() { if (!adi_heap_debug_set_guard_region(0x11111111, 0x22222222, 0x33333333) { printf("failed to change guard regions\n"); return false; } return true; } CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-99 Documented Library Functions See Also adi_heap_debug_reset_guard_region 1-100 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library adi_heap_debug_set_ignore Change error types to be ignored Synopsis #include void adi_heap_debug_set_ignore(unsigned long flag); Description The adi_heap_debug_set_ignore function configures an error class as ignored. These types are represented as a bit-field using macros defined in heap_debug.h. Ignored errors produce no run-time diagnostics, but will appear in the heap debugging report (if generated). errors need to be enabled for these changes to have any Run-time effect. For more information on heap debugging, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions None. Example #include void ignore_unwanted_errors() { // Enable run-time diagnostics adi_heap_debug_enable(_HEAP_STDERR_DIAG); CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-101 Documented Library Functions // Don't produce run-time diagnostics about frees // from the wrong heap or heap operations used // from within an interrupt adi_heap_debug_set_ignore(_HEAP_ERROR_WRONG_HEAP | _HEAP_ERROR_IN_ISR); } See Also adi_heap_debug_enable, adi_heap_debug_set_error, adi_heap_debug_set_warning 1-102 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library adi_heap_debug_set_warning Change error types to be regarded as run-time warning Synopsis #include void adi_heap_debug_set_warning(unsigned long flag); Description The adi_heap_debug_set_warning function configures an error class to be regarded as a warning. These types are represented as a bit-field using macros defined in heap_debug.h. A warning diagnostic is produced at runtime if an error of that class is detected, but the application will not terminate. Any detected errors are recorded in the heap debugging report (if generated) as normal. If the heap debugging library is unable to write a warning to stderr due to being in an interrupt or an unscheduled region, then the warning will be treated as an error and adi_fatal_error will be called. For this reason, setting _HEAP_ERROR_IN_ISR (heap usage within interrupt) to be a warning has no effect. errors need to be enabled for these changes to have any Run-time effect. For more information on heap debugging, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions None. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-103 Documented Library Functions Example #include void set_warnings() { // Enable run-time diagnostics adi_heap_debug_enable(_HEAP_STDERR_DIAG); // Produce warnings about de-allocating and // reallocating pointers not returned by an // allocation function and about de-allocations // not using functions which correspond to an // allocation, but don't terminate the application // on detection adi_heap_debug_set_warning(_HEAP_ERROR_INVALID_ADDRESS | _HEAP_ERROR_FUNCTION_MISMATCH); } See Also adi_heap_debug_enable, adi_heap_debug_set_error, adi_heap_debug_set_ignore 1-104 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library adi_verify_all_heaps Verify that no heaps contain corrupt blocks Synopsis #include bool adi_verify_all_heaps(void); Description The adi_verify_all_heaps function checks that each heap tracked by the heap debugging library contains no corrupted guard regions and that the underlying heap structure is correct. If a corrupt guard region is detected on any heaps then adi_verify_all_heaps will return false, otherwise true will be returned. adi_verify_all_heaps function relies on the heap usage being The tracked by the heap debugging library. Any heap activity carried out when heap usage is not being tracked (when heap debugging is paused or disabled) is not checked for corruption. For more information on heap debugging, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions The adi_verify_all_heaps function returns false if any corrupt guard regions are detected on any heap. Example #include #include void check_heaps() { CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-105 Documented Library Functions if (!adi_verify_all_heaps()) { printf("heaps contain corruption\n"); } else { printf("heaps are ok\n"); } } See Also adi_verify_heap 1-106 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library adi_verify_heap Verify that a heap contains no corrupt blocks Synopsis #include bool adi_verify_heap(int heapindex); Description The adi_verify_heap function checks that the heap specified with the index heapindex has no corrupt guard regions. If any guard region corruption is detected on that heap then adi_verify_heap returns false; otherwise, true is returned. The heap index of static heaps can be identified by using heap_malloc. The heap index of a dynamically defined heap is the value returned from heap_install. adi_verify_heap function relies on the heap usage being The tracked by the heap debugging library. Any heap activity carried out when heap usage is not being tracked (when heap debugging is paused or disabled) is not be checked for corruption. For more information on heap debugging, see the section "Heap Debugging" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions The adi_verify_heap function returns false if any corrupt guard regions are detected on the specified heap. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-107 Documented Library Functions Example #include #include void check_heap(int heapindex) { if (!adi_verify_heap(heapindex)) { printf("heap %d contain corruption\n", heapindex); } else { printf("heap %d is ok\n", heapindex); } } See Also adi_verify_all_heaps 1-108 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library asctime Convert broken-down time into a string Synopsis #include char *asctime(const struct tm *t); Description The asctime function converts a broken-down time, as generated by the functions gmtime and localtime, into an ASCII string that will contain the date and time in the form DDD MMM dd hh:mm:ss YYYY\n where * DDD represents the day of the week (that is, Mon, Tue, Wed, etc.) * MMM is the month and will be of the form Jan, Feb, Mar, etc * dd is the day of the month, from 1 to 31 * hh is the number of hours after midnight, from 0 to 23 * mm is the minute of the day, from 0 to 59 * ss is the second of the day, from 0 to 61 (to allow for leap seconds) * YYYY represents the year The function returns a pointer to the ASCII string, which may be overwritten by a subsequent call to this function. Also note that the function ctime returns a string that is identical to asctime(localtime(&t)) CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-109 Documented Library Functions Error Conditions None. Example #include #include struct tm tm_date; printf("The date is %s",asctime(&tm_date)); See Also ctime, gmtime, localtime 1-110 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library asin Arc sine Synopsis #include float asinf (float x); double asin (double x); long double asind (long double x); Description The arc sine functions return the arc sine of the first argument. The input must be in the range [1, 1]. The output, in radians, is in the range - to . Error Conditions The arc sine functions indicate a domain error (set errno to EDOM) and return a zero if the input is not in the range [-1, 1]. Example #include double y; float x; y = asin (1.0); /* y = /2 */ x = asinf (1.0); /* x = /2 */ See Also sin CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-111 Documented Library Functions atan Arc tangent Synopsis #include float atanf (float x); double atan (double x); long double atand (long double x); Description The arc tangent functions return the arc tangent of the first argument. The output, in radians, is in the range - to . Error Conditions None. Example #include double y; float x; y = atan (0.0); /* y = 0.0 */ x = atanf (0.0); /* x = 0.0 */ See Also atan2, tan 1-112 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library atan2 Arc tangent of quotient Synopsis #include float atan2f (float y, float x); double atan2 (double y, double x); long double atan2d (long double y, long double x); Description The atan2 functions compute the arc tangent of the input value y divided by input value x. The output, in radians, is in the range - to . Error Conditions The atan2 functions return a zero if x=0 and y=0. Example #include double a,d; float b,c; a = atan2 (0.0, 0.0); /* the error condition: a = 0.0 */ b = atan2f (1.0, 1.0); /* b = /4 c = atan2f (1.0, 0.0); /* c = /2 d = atan2 (-1.0, 0.0); /* d = */ */ -/2 */ See Also atan, tan CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-113 Documented Library Functions atexit Register a function to call at program termination Synopsis #include int atexit (void (*func)(void)); Description The atexit function registers a function to be called at program termination. Functions are called once for each time they are registered, in the reverse order of registration. Up to 32 functions can be registered using the atexit function. Error Conditions The atexit function returns a non-zero value if the function cannot be registered. Example #include extern void goodbye(void); if (atexit(goodbye)) exit(1); See Also abort, exit 1-114 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library atof Convert string to a double Synopsis #include double atof(const char *nptr); Description The atof function converts a character string into a floating-point value of type double, and returns its value. The character string is pointed to by the argument nptr and may contain any number of leading whitespace characters (as determined by the function isspace) followed by a floating-point number. The floating-point number may either be a decimal floating-point number or a hexadecimal floating-point number. A decimal floating-point number has the form: [sign] [digits] [.digits] [{e|E} [sign] [digits]] The sign token is optional and is either plus ( + ) or minus ( - ); and digits are one or more decimal digits. The sequence of digits may contain a decimal point ( . ). The decimal digits can be followed by an exponent, which consists of an introductory letter (e or E ) and an optionally signed integer. If neither an exponent part nor a decimal point appears, a decimal point is assumed to follow the last digit in the string. The form of a hexadecimal floating-point number is: [sign] [{0x}|{0X}] [hexdigs] [.hexdigs] [{p|P} [sign] [digits]] A hexadecimal floating-point number may start with an optional plus ( + ) or minus ( - ) followed by the hexadecimal prefix 0x or 0X. This character CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-115 Documented Library Functions sequence must be followed by one or more hexadecimal characters that optionally contain a decimal point ( . ). The hexadecimal digits are followed by a binary exponent that consists of the letter p or P, an optional sign, and a non-empty sequence of decimal digits. The exponent is interpreted as a power of two that is used to scale the fraction represented by the tokens [hexdigs] [.hexdigs]. The first character that does not fit either form of number stops the scan. Error Conditions The atof function returns a zero if no conversion could be made. If the correct value results in an overflow, a positive or negative (as appropriate) HUGE_VAL is returned. If the correct value results in an underflow, 0.0 is returned. The ERANGE value is stored in errno in the case of either an overflow or underflow. Notes The atof (pdata) function reference is functionally equivalent to: strtod (pdata, (char *) NULL); and therefore, if the function returns zero, it is not possible to determine whether the character string contained a (valid) representation of 0.0 or some invalid numerical string. Example #include double x; x = atof("5.5"); 1-116 /* x = 5.5 */ CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also atoi, atol, atoll, strtod CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-117 Documented Library Functions atoi Convert string to integer Synopsis #include int atoi (const char *nptr); Description The atoi function converts a character string to an integer value. The character string to be converted is pointed to by the input pointer, nptr. The function clears any leading characters for which isspace would return true. Conversion begins at the first digit (with an optional preceding sign) and terminates at the first non-digit. Error Conditions The atoi function returns 0 if no conversion can be made. Example #include int i; i = atoi ("5"); /* i = 5 */ See Also atof, atol, atoll, strtod 1-118 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library atol Convert string to long integer Synopsis #include long atol (const char *nptr); Description The atol function converts a character string to a long integer value. The character string to be converted is pointed to by the input pointer, nptr. The function clears any leading characters for which isspace would return true. Conversion begins at the first digit (with an optional preceding sign) and terminates at the first non-digit. is no way to determine if a zero is a valid result or an indica There tor of an invalid string. Error Conditions The atol function returns 0 if no conversion can be made. Example #include long int i; i = atol ("5"); /* i = 5 */ See Also atof, atoi, atoll, strtod, strtol, strtoll, strtoul, strtoull CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-119 Documented Library Functions atold Convert string to a long double Synopsis #include long double atold(const char *nptr); Description The atold function is an extension to the ISO/IEC 9899:1990 C standard and the ISO/IEC 9899:1999 C standard. The atold function converts a character string into a floating-point value of type long double, and returns its value. The character string is pointed to by the argument nptr and may contain any number of leading whitespace characters (as determined by the function isspace) followed by a floating-point number. The floating-point number may either be a decimal floating-point number or a hexadecimal floating-point number. A decimal floating-point number has the form: [sign] [digits] [.digits] [{e|E} [sign] [digits]] The sign token is optional and is either plus ( + ) or minus ( - ); and digits are one or more decimal digits. The sequence of digits may contain a decimal point ( . ). The decimal digits can be followed by an exponent, which consists of an introductory letter (e or E ) and an optionally signed integer. If neither an exponent part nor a decimal point appears, a decimal point is assumed to follow the last digit in the string. The form of a hexadecimal floating-point number is: [sign] [{0x}|{0X}] [hexdigs] [.hexdigs] [{p|P} [sign] [digits]] 1-120 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library A hexadecimal floating-point number may start with an optional plus ( + ) or minus ( - ) followed by the hexadecimal prefix 0x or 0X. This character sequence must be followed by one or more hexadecimal characters that optionally contain a decimal point ( . ). The hexadecimal digits are followed by a binary exponent that consists of the letter p or P, an optional sign, and a non-empty sequence of decimal digits. The exponent is interpreted as a power of two that is used to scale the fraction represented by the tokens [hexdigs] [.hexdigs]. The first character that does not fit either form of number stops the scan. Error Conditions The atold function returns a zero if no conversion could be made. If the correct value results in an overflow, a positive or negative (as appropriate) LDBL_MAX is returned. If the correct value results in an underflow, 0.0 is returned. The ERANGE value is stored in errno in the case of either an overflow or underflow. Notes The atold (pdata) function reference is functionally equivalent to: strtold (pdata, (char *) NULL); and therefore, if the function returns zero, it is not possible to determine whether the character string contained a (valid) representation of 0.0 or some invalid numerical string. Example #include long double x; x = atold("5.5"); /* x = 5.5 */ CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-121 Documented Library Functions See Also atoi, atol, atoll, strtold 1-122 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library atoll Convert string to long long integer Synopsis #include long long atoll (const char *nptr); Description The atoll function converts a character string to a long long integer value. The character string to be converted is pointed to by the input pointer, nptr. The function clears any leading characters for which isspace would return true. Conversion begins at the first digit (with an optional preceding sign) and terminates at the first non-digit. is no way to determine if a zero is a valid result or an indica There tor of an invalid string. Error Conditions The atoll function returns 0 if no conversion can be made. Example #include long long i; i = atoll ("150000000000000"); /* i = 150000000000000LL */ See Also atof, atoi, atol, strtod, strtol, strtoll, strtoul, strtoull CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-123 Documented Library Functions avg Mean of two values Synopsis #include int avg (int x, int y); Description The avg function is an Analog Devices extension to the ANSI standard. The avg function adds two arguments and divides the result by two. The avg function is a built-in function which is implemented with an Rn=(Rx+Ry)/2 instruction. Error Conditions None. Example #include int i; i = avg (10, 8); /* returns 9 */ See Also lavg, llavg 1-124 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library bitsfx Bitwise fixed-point to integer conversion Synopsis #include int_hr_t bitshr(short fract f); int_r_t bitsr(fract f); int_lr_t bitslr(long fract f); uint_uhr_t bitsuhr(unsigned short fract f); uint_ur_t bitsur(unsigned fract f); uint_ulr_t bitsulr(unsigned long fract f); Description Given a fixed-point operand, the bitsfx family of functions return the fixed-point value multiplied by 2F, where F is the number of fractional bits in the fixed-point type. This is equivalent to the bit-pattern of the fixed-point value held in an integer type. Error Conditions None. Example #include uint_ulr_t ulr; ulr = bitsulr(0.125ulr); /* ulr == 0x20000000 */ See Also fxbits CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-125 Documented Library Functions bsearch Perform binary search in a sorted array Synopsis #include void *bsearch (const void *key, const void *base, size_t nelem, size_t size, int (*compare)(const void *, const void *)); Description The bsearch function searches the array base for an array element that matches the element key. The size of each array element is specified by size, and the array is defined to have nelem array elements. The bsearch function will call the function compare with two arguments; the first argument will point to the array element key and the second argument will point to an element of the array. The compare function should return an integer that is either zero, or less than zero, or greater than zero, depending upon whether the array element key is equal to, less than, or greater than the array element pointed to by the second argument. If the comparison function returns a zero, then bsearch will return a pointer to the matching array element; if there is more than one matching elements then it is not defined which element is returned. If no match is found in the array, bsearch will return NULL. The array to be searched would normally be sorted according to the criteria used by the comparison function (the qsort function may be used to first sort the array if necessary). 1-126 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Error Conditions The bsearch function returns a null pointer when the key is not found in the array. Example #include #include #define SIZE 3 struct record_t { char *name; char *street; char *city; }; struct record_t {"Baby Doe" {"Jane Doe" {"John Doe" }; data_base[SIZE] = { , "Central Park" , "New York"}, , "Regents Park" , "London" }, , "Queens Park" , "Sydney" } static int compare_function (const void *arg1, const void *arg2) { const struct record_t *pkey = arg1; const struct record_t *pbase = arg2; return strcmp (pkey->name,pbase->name); } struct record_t key = {"Baby Doe" , "" , ""}; struct record_t *search_result; search_result = bsearch (&key, data_base, SIZE, sizeof(struct record_t), compare_function); CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-127 Documented Library Functions See Also qsort 1-128 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library calloc Allocate and initialize memory Synopsis #include void *calloc (size_t nmemb, size_t size); Description The calloc function dynamically allocates a range of memory and initializes all locations to zero. The number of elements (the first argument) multiplied by the size of each element (the second argument) is the total memory allocated. The memory may be deallocated with the free function. The object is allocated from the current heap, which is the default heap unless heap_switch has been called to change the current heap to an alternate heap. Error Conditions The calloc function returns a null pointer if unable to allocate the requested memory. Example #include int *ptr; ptr = (int *) calloc (10, sizeof (int)); /* ptr points to a zeroed array of length 10 */ CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-129 Documented Library Functions See Also free, heap_calloc, heap_free, heap_malloc, heap_realloc, malloc, realloc 1-130 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library ceil Ceiling Synopsis #include float ceilf (float x); double ceil (double x); long double ceild (long double x); Description The ceiling functions return the smallest integral value that is not less than the argument x. Error Conditions None. Example #include double y; float x; y = ceil (1.05); /* y = 2.0 x = ceilf (-1.05); /* y = -1.0 */ */ See Also floor CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-131 Documented Library Functions clearerr Clear file or stream error indicator Synopsis #include void clearerr(FILE *stream); Description The clearerr function clears the error and end-of-file (EOF) indicators for the particular stream pointed to by stream. The stream error indicators record whether any read or write errors have occurred on the associated stream. The EOF indicator records when there is no more data in the file. Error Conditions None. Example #include FILE *routine(char *filename) { FILE *fp; fp = fopen(filename, "r"); /* Some operations using the file */ /* now clear the error indicators for the stream */ clearerr(fp); return fp; } 1-132 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also feof, ferror CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-133 Documented Library Functions clip Clip Synopsis #include int clip (int value1, int value2); Description The clip function is an Analog Devices extension to the ANSI standard. The clip function returns its first argument if its absolute value is less than the absolute value of its second argument, otherwise it returns the absolute value of its second argument if the first is positive, or minus the absolute value if the first argument is negative. The clip function is a built-in function which is implemented with an Rn = CLIP Rx BY Ry instruction. Error Conditions None. Example #include int i; i = clip (10, 8); /* returns 8 */ i = clip (8, 10); /* returns 8 */ i = clip (-10, 8); /* returns -8 */ See Also fclip, lclip, llclip 1-134 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library clock Processor time Synopsis #include clock_t clock(void); Description The clock function returns the number of processor cycles that have elapsed since an arbitrary starting point. The function returns the value (clock_t) -1, if the processor time is not available or if it cannot be represented. The result returned by the function may be used to calculate the processor time in seconds by dividing it by the macro CLOCKS_PER_SEC. For more information, see time.h. An alternative method of measuring the performance of an application is described in Measuring Cycle Counts. Error Conditions None. Example #include time_t start_time,stop_time; double time_used; start_time = clock(); compute(); stop_time = clock(); time_used = ((double) (stop_time - start_time)) / CLOCKS_PER_SEC; CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-135 Documented Library Functions See Also No related functions. 1-136 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library cos Cosine Synopsis #include float cosf (float x); double cos (double x); long double cosd (long double x); Description The cosine functions return the cosine of the first argument. The input is interpreted as radians; the output is in the range [-1, 1]. Error Conditions The input argument x for cosf must be in the domain [-1.647e6, 1.647e6] and the input argument for cosd must be in the domain [-8.433e8, 8.433e8]. The functions return zero if x is outside their domain. Example #include double y; float x; y = cos (3.14159); /* y = -1.0 */ x = cosf (3.14159); /* x = -1.0 */ See Also acos, sin CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-137 Documented Library Functions cosh Hyperbolic cosine Synopsis #include float coshf (float x); double cosh (double x); long double coshd (long double x); Description The hyperbolic cosine functions return the hyperbolic cosine of their argument. Error Conditions The domain of coshf is [-89.39, 89.39], and the domain for coshd is [-710.44, 710.44]. The functions return HUGE_VAL if the input argument x is outside the respective domains. Example #include float x; double y; x = coshf ( 1.0); /* x = 1.54308 */ y = cosh /* y = 1.54308 */ (-1.0); See Also sinh 1-138 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library count_ones Count one bits in word Synopsis #include int count_ones (int value); Description The count_ones function is an Analog Devices extension to the ANSI standard. The count_ones function returns the number of one bits in its argument. Error Conditions None. Example #include int flags1 = 0xAD1; int flags2 = -1; int cnt1; int cnt2; cnt1 = count_ones (flags1); /* returns 6 */ cnt2 = count_ones (flags2); /* returns 32 */ See Also lcount_ones, llcount_ones CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-139 Documented Library Functions countlsfx Count leading sign or zero bits Synopsis #include int countlshr(short fract f); int countlsr(fract f); int countlslr(long fract f); int countlsuhr(unsigned short fract f); int countlsur(unsigned fract f); int countlsulr(unsigned long fract f); Description Given a fixed-point operand x, the countlsfx family of functions return the largest value of n for which x << n does not overflow. For a zero input value, the function will return the number of bits in the fixed-point type. In addition to the individually-named functions for each fixed-point type, a type-generic macro countlsfx is defined for use in C99 mode. This may be used with any of the fixed-point types. Error Conditions None. Example #include int n; n = countlsulr(0.125ulr); /* n == 2 */ n = countlsfx(0.125ulr); /* n == 2 */ 1-140 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also No related functions. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-141 Documented Library Functions ctime Convert calendar time into a string Synopsis #include char *ctime(const time_t *t); Description The ctime function converts a calendar time, pointed to by the argument t into a string that represents the local date and time. The form of the string is the same as that generated by asctime, and so a call to ctime is equivalent to asctime(localtime(&t)) A pointer to the string is returned by ctime, and it may be overwritten by a subsequent call to the function. Error Conditions None. Example #include #include time_t cal_time; if (cal_time != (time_t)-1) printf("Date and Time is %s",ctime(&cal_time)); 1-142 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also asctime, gmtime, localtime, time CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-143 Documented Library Functions difftime Difference between two calendar times Synopsis #include double difftime(time_t t1, time_t t0); Description The difftime function returns the difference in seconds between two calendar times, expressed as a double. By default, the double data type represents a 32-bit, single precision, floating-point, value. This form is normally insufficient to preserve all of the bits associated with the difference between two calendar times, particularly if the difference represents more than 97 days. It is recommended therefore that any function that calls difftime is compiled with the -double-size-64 switch. Error Conditions None. Example #include #include #define NA ((time_t)(-1)) time_t cal_time1; time_t cal_time2; double time_diff; 1-144 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library if ((cal_time1 == NA) || (cal_time2 == NA)) printf("calendar time difference is not available\n"); else time_diff = difftime(cal_time2,cal_time1); See Also time CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-145 Documented Library Functions div Division Synopsis #include div_t div (int numer, int denom); Description The div function divides numer by denom, both of type int, and returns a structure of type div_t. The type div_t is defined as: typedef struct { int quot; int rem; } div_t; where quot is the quotient of the division and rem is the remainder, such that if result is of type div_t, then result.quot * denom + result.rem == numer Error Conditions If denom is zero, the behavior of the div function is undefined. Example #include div_t result; result = div (5, 2); 1-146 /* result.quot = 2, result.rem = 1 */ CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also divifx, fmod, fxdivi, idivfx, ldiv, lldiv, modf CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-147 Documented Library Functions divifx Division of integer by fixed-point to give integer result Synopsis #include int divir(int numer, fract denom); long int divilr(long int numer, long fract denom); unsigned int diviur(unsigned int numer, unsigned fract denom); unsigned long int diviulr(unsigned long int numer, unsigned long fract denom); Description Given an integer numerator and a fixed-point denominator, the divifx family of functions computes the quotient and returns the closest integer value to the result. Error Conditions The divifx function has undefined behavior if the denominator is zero. Example #include unsigned long int ulquo; ulquo = diviulr(125, 0.125ulr); /* ulquo == 1000 */ See Also div, fxdivi, idivfx, ldiv, lldiv 1-148 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library dyn_AddHeap Specify a new region of target memory which may be used for relocated, dynamically-loaded code and data Synopsis #include DYN_RESULT dyn_AddHeap(dyn_mem_image *image, dyn_heap *heap); Description The dyn_AddHeap function declares a new region of target memory that may be used to relocate the code or data in dynamically-loadable module (DLM) image, as previously validated by dyn_ValidateImage. The heap parameter indicates the width and alignment of the memory, as well as the start and size. The heap parameter must point to a dyn_heap structure that has been initialized by dyn_heap_init. Error Conditions The dyn_AddHeap function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. The heap was added to the image's list of regions from which to allocate target memory. DYN_BAD_PTR Either image or heap was NULL. DYN_BAD_WIDTH A heap has already been specified which has the same width as the heap being added. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-149 Documented Library Functions Example #include DYN_RESULT data_heap(dyn_mem_image *image) {, static int myspace[50]; static dyn_heap h[1]; dyn_heap_init(h, myspace, sizeof(myspace), 4, 2); /* error-checking omitted */ return dyn_AddHeap(image, h); } See Also dyn_ValidateImage, dyn_heap_init, dyn_SetSectionAddr, dyn_FreeSectionMem, dyn_AllocSectionMemHeap, malloc 1-150 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library dyn_alloc Allocate space from a target heap Synopsis #include DYN_RESULT dyn_alloc(dyn_heap *heap, size_t naddrs, void **ptr); Description The dyn_alloc function allocates a number of contiguous addressable locations from the target heap specified by the heap parameter. The first of these allocated locations is returned as the address pointed-to by the ptr parameter. The naddrs parameter indicates how many contiguous locations must be allocated. This function is not normally called directly; it is used by dyn_AllocSecand dyn_AllocSectionMemHeap. tionMem Error Conditions The dyn_alloc function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. The space was allocated. DYN_BAD_PTR Either ptr or heap was NULL. DYN_BAD_IMAGE The available space in the heap is not aligned according to the heap's alignment. This should never occur. DYN_TOO_SMALL There is insufficient space left in the heap to allocate naddrs locations in an aligned manner. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-151 Documented Library Functions Example #include void *get_space(dyn_heap *heap) { void *ptr = 0; if (dyn_alloc(heap, 100, &ptr) == DYN_NO_ERROR) return ptr; return 0; } See Also dyn_ValidateImage, dyn_heap_init, dyn_AddHeap, dyn_Relocate, dyn_FreeSectionMem, dyn_AllocSectionMemHeap, malloc 1-152 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library dyn_AllocSectionMem Allocate target memory aligned for a section in a dynamically-loadable module Synopsis #include DYN_RESULT dyn_AllocSectionMem(dyn_mem_image *image, dyn_section *sections, size_t secnum, dyn_section_mem **mem); Description The dyn_AllocSectionMem function allocates a target memory buffer large enough to hold the contents of section secnum, in dynamically-loadable module (DLM) image, as previously validated by dyn_ValidateImage. The sections parameter is a local copy of the DLM's section table, obtained by dyn_GetSections. The memory allocated by this function should be freed in a single step at a later time, by calling dyn_FreeSectionMem. Two areas of memory are allocated by this function: 1. A space is allocated in target memory to hold the contents of the section. This space is allocated by dyn_alloc from a heap defined by dyn_AddHeap; the heap in question is selected on the basis of the memory width of the section secnum, by the dyn_GetHeapForWidth function. 2. A space is allocated in local memory to keep track of this allocation. This memory is allocated from the default heap, and is attached to image, so that it may be freed later. On exit, *mem points to the second of the two allocations. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-153 Documented Library Functions Error Conditions The dyn_AllocSectionMem function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. *mem contains a pointer to a suitable block of memory; mem->aligned_addr can be used by dyn_SetSectionAddr for section secnum. DYN_BAD_PTR One or more of the pointer parameters was NULL. DYN_NO_MEM Malloc failed, when attempting to allocate sufficient memory. DYN_BAD_IMAGE The secnum parameter does not refer to a valid section in the DLM. Example #include dyn_section_mem *secmem(dyn_mem_image *image, dyn_section *sections, int nsecs) { int i; dyn_section_mem *mem = 0; for (i = 0; i < nsecs; i++) { if (dyn_AllocSectionMem(image, sections, i, &mem) != DYN_NO_ERROR) { return NULL; } } return mem; } 1-154 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also dyn_AddHeap, dyn_ValidateImage, dyn_alloc, dyn_GetHeapForWidth, dyn_Relocate, dyn_FreeSectionMem, dyn_AllocSectionMemHeap, malloc CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-155 Documented Library Functions dyn_AllocSectionMemHeap Allocate memory from a given heap, aligned for a section in a dynamically-loadable module Synopsis #include DYN_RESULT dyn_AllocSectionMemHeap(dyn_mem_image *image, dyn_section *sections, size_t secnum, dyn_section_mem **mem, int heapidx); Description The dyn_AllocSectionMemHeap function allocates a target memory buffer large enough to hold the contents of section secnum, in dynamically-loadable module (DLM) image, as previously validated by dyn_ValidateImage. The sections parameter is a local copy of the DLM's section table, obtained by dyn_GetSections. The memory allocated by this function should be freed in a single step at a later time, by calling dyn_FreeSectionMem. The heapidx parameter indicates which heap should be used to allocate house-keeping space. Two areas of memory are allocated by this function: 1. A space is allocated in target memory to hold the contents of the section. This space is allocated by dyn_alloc from a heap defined by dyn_AddHeap; the heap in question is selected on the basis of the memory width of the section secnum by dyn_GetHeapForWidth. 2. A space is allocated in local memory to keep track of this allocation. This memory is allocated using heap_malloc, with the heap in question specified by heapidx. The resulting memory is attached to image, so that it may be freed later. 1-156 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library On exit, *mem points to the second of the two allocations. Error Conditions The dyn_AllocSectionMemHeap function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. *mem contains a pointer to a suitable block of memory; mem->aligned_addr can be used by dyn_SetSectionAddr for section secnum. DYN_BAD_PTR One or more of the pointer parameters was NULL. DYN_NO_MEM Malloc failed, when attempting to allocate sufficient memory. DYN_BAD_IMAGE The secnum parameter does not refer to a valid section in the DLM. Example #include dyn_section_mem *secmem(dyn_mem_image *image, dyn_section *sections, int nsecs) { int i; dyn_section_mem *mem = 0; for (i = 0; i < nsecs; i++) { if (dyn_AllocSectionMemHeap(image, sections, i, &mem, 0) != DYN_NO_ERROR) return NULL; } return mem; } CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-157 Documented Library Functions See Also dyn_AddHeap, dyn_ValidateImage, dyn_GetHeapForWidth, dyn_alloc, dyn_Relocate, dyn_FreeSectionMem, dyn_AllocSectionMemHeap, malloc 1-158 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library dyn_CopySectionContents Copy the sections of a valid dynamically-loadable module Synopsis #include DYN_RESULT dyn_CopySectionContents(dyn_mem_image *image, dyn_section *sections); Description The dyn_CopySectionContents function will copy the contents of all sections from a dynamically-loadable module (DLM), into previously-allocated local space. image is a DLM previously validated by dyn_ValidateImage, and sections is a local copy of the DLM's section table, obtained by dyn_GetSections. An address must have previously been allocated to each section, by dyn_SetSectionAddr. Error Conditions The dyn_CopySectionContents function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. The DLM section contents were copied. DYN_BAD_PTR The sections or image parameter is NULL. DYN_BAD_IMAGE The image does not have the right magic number, or offsets within the image are nonsensical. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-159 Documented Library Functions Example #include int copy_dlm(dyn_mem_image *image, dyn_sections *secs) { if (dyn_CopySectionContents(image, secs) == DYN_NO_ERROR) return 0; return -1; } See Also dyn_ValidateImage, dyn_GetNumSections, dyn_GetSections, dyn_GetStringTableSize, dyn_GetStringTable, dyn_GetExpSymTab, dyn_LookupByName, dyn_Relocate, dyn_SetSectionAddr, dyn_AllocSectionMem 1-160 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library dyn_FreeEntryPointArray Release a previously-allocated list of entry points to the dynamically-loadable module Synopsis #include void dyn_FreeEntryPointArray(char *strtab, char **entries); Description The dyn_FreeEntryPointArray function releases memory that was allocated by dyn_GetEntryPointArray. Error Conditions None. Example See dyn_GetEntryPointArray for an example. See Also dyn_ValidateImage, dyn_GetExpSymTab, dyn_LookupByName, dyn_Relocate, dyn_GetEntryPointArray CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-161 Documented Library Functions dyn_FreeSectionMem Release memory allocated for sections in a dynamically-loadable module Synopsis #include void dyn_FreeSectionMem(dyn_mem_image *image); Description The dyn_FreeSectionMem function releases house-keeping memory blocks that were allocated by dyn_AllocSectionMem or dyn_AllocSectionMemHeap. image is a DLM previously validated by dyn_ValidateImage. Target memory, allocated from heaps declared by dyn_AddHeap, remains valid. Error Conditions None. Example #include void secmem(dyn_mem_image *image,dyn_section *sections ,int nsecs) { int i; dyn_section_mem *mem = 0; for (i = 0; i < nsecs; i++) { if (dyn_AllocSectionMem(image, sections, i, &mem) != DYN_NO_ERROR) return; } 1-162 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library do_something(); dyn_FreeSectionMem(image); return; } See Also dyn_ValidateImage, dyn_GetNumSections, dyn_GetSections, dyn_GetStringTableSize, dyn_GetStringTable, dyn_GetExpSymTab, dyn_LookupByName, dyn_Relocate, dyn_SetSectionAddr, dyn_CopySectionContents, dyn_AllocSectionMem CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-163 Documented Library Functions dyn_GetEntryPointArray Obtain a list of symbols exported by a dynamically-loadable module Synopsis #include DYN_RESULT dyn_GetEntryPointArray(dyn_mem_image *image, size_t symidx, size_t stridx, char **hstrtab, char ***entries, size_t *num_entries); Description The dyn_GetEntryPointArray function obtains the contents of the exported symbol table of the dynamically-loadable module (DLM) image, in an array of string pointers, pointed to by *entries. *num_entries is set to contain the number of entries in the allocated array. Each entry in the allocated array points to a string in a local copy of the string table, converted to local string format. *entries is set to point to this local string table. This function can be used to determine which symbols are exported by the DLM, if this is not known in advance. Once the array of entry-point strings has been obtained, the strings can be passed to dyn_LookupByName to determine the resolved address of the entry-point. This function may only be called after the DLM has been relocated by calling dyn_Relocate; prior to that point, the exported symbol table's entries are not completely resolved. The symidx and stridx parameters identify the sections that contain the exported symbol table and exported string table, respectively; these parameters are obtained via dyn_GetExpSymTab. 1-164 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library The allocated memory should be freed by dyn_FreeEntryPointArray, once it is no longer required. Error Conditions The dyn_GetEntryPointArray function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. *ptr contains the address of the symbol, in the relocated image. DYN_BAD_PTR One or more of the pointer parameters is NULL. DYN_NO_MEM There was not enough space to allocate either the entry array, or the local copy of the string table. DYN_NOT_FOUND The sections for the exported string table or exported symbol table could not be retrieved. Example #include #include void list_syms(dyn_mem_image *image, const char *strtab, dyn_section *sections) { size_t symidx, stridx; char *hstrtab, **syms; int i, nsyms; dyn_GetExpSymTab(image, symtab, sections, &symidx, &stridx); dyn_GetEntryPointArray(image, symidx, stridx, &hstrtab, &nsyms, &syms); for (i = 0; i < nsyms; i++) printf("Sym %d is %s\n", i, syms[i]); dyn_FreeEntryPointArray(hstrtab, syms); } CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-165 Documented Library Functions See Also dyn_ValidateImage, dyn_GetNumSections, dyn_GetSections, dyn_GetStringTableSize, dyn_GetStringTable, dyn_GetExpSymTab, dyn_Relocate, dyn_SetSectionAddr, dyn_AllocSectionMem, dyn_CopySectionContents 1-166 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library dyn_GetExpSymTab Locate a dynamically-loadable module's table of exported symbols Synopsis #include DYN_RESULT dyn_GetExpSymTab(dyn_mem_image *image, const char *strtab, dyn_section *sections, size_t *symidx, size_t *stridx); Description The dyn_GetExpSymTab function searches the dynamically-loadable module (DLM) pointed to by image, looking for the table of exported symbols. The strtab and sections parameters must be pointers to the DLM's string table and section table, obtained by dyn_GetStringTable and dyn_GetSections, respectively. The DLM's exported-symbol table consists of two sections. One is a string table, containing the names of exported symbols in native processor format; the other is a table where each entry points to the symbol's name in said string table, and to the symbol itself (whether code or data). If successful, the function records the section numbers of the exported section table and exported string table into the locations pointed to by symidx and stridx, respectively. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-167 Documented Library Functions Error Conditions The dyn_GetExpSymTab function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. *symidx contains the section number containing the exported symbol table, and *stridx contains the section number containing the exported string table. DYN_BAD_PTR One or more of the parameters is NULL. DYN_BAD_IMAGE The function could not locate sections for both the exported string table and the exported symbol table. Example #include static size_t sec_tab, str_tab; int find_secs(dyn_mem_image *image, const char strtab, dyn_section *sections) { if (dyn_GetExpSymTab(image, strtab, sections, &sec_tab, &str_tab) == DYN_NO_ERROR) return 0; return -1; } See Also dyn_ValidateImage, dyn_GetNumSections, dyn_GetSections, dyn_GetStringTableSize, dyn_GetStringTable, dyn_LookupByName, dyn_Relocate, dyn_SetSectionAddr, dyn_AllocSectionMem, dyn_CopySectionContents 1-168 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library dyn_GetHeapForWidth Locate a target-memory heap that has the right number of bits per addressable unit. Synopsis #include DYN_RESULT dyn_GetHeapForWidth(dyn_mem_image *image, size_t byte_width, dyn_heap **heap); Description The dyn_GetHeapForWidth function searches all target-memory heaps that have been declared for this image (using the dyn_AddHeap function), and returns the one that has a width of byte_width via *heap, if there is one. Error Conditions The dyn_GetHeapForWidth function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. *heap contains a pointer to a heap which may be used for allocation. DYN_BAD_PTR Either heap or image was NULL. DYN_NOT_FOUND No heap has been attached to image using dyn_AddHeap(), which has a width that matches byte_width. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-169 Documented Library Functions Example #include dyn_heap *fetch_heap(dyn_mem_image *image, size_t width) { dyn_heap *heap = 0; if (dyn_GetHeapForWidth(image, &heap) != DYN_NO_ERROR) return NULL; return heap; } See Also dyn_AddHeap, dyn_ValidateImage, dyn_heap_init, dyn_alloc, dyn_FreeSectionMem, dyn_AllocSectionMemHeap, malloc 1-170 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library dyn_GetNumSections Obtain the number of sections in a dynamically-loadable module Synopsis #include DYN_RESULT dyn_GetNumSections(dyn_mem_image *image, size_t *num_sections); Description The dyn_GetNumSections function returns the number of sections in a validate dynamically-loadable module (DLM), as produced by elf2dyn. The image parameter should have been populated by a previous call to dyn_ValidateImage. In the context of this function, "sections" means "portions of the DLM that contain executable code or usable data"; it does not include the string table or any relocations for the DLM. Upon success, the function writes the number of sections to the location pointed to by the num_sections parameter. Error Conditions The dyn_GetNumSections function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. *num_sections will contain the section count. DYN_BAD_PTR The image or num_sections parameter is NULL. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-171 Documented Library Functions Example #include #include void count_sections(dyn_mem_image *dlm_info) { size_t nsec; if (dyn_GetNumSections(dlm_info, &nsec) == DYN_NO_ERROR) printf("There are %d section\n", nsec); } See Also dyn_ValidateImage, dyn_GetSections, dyn_GetStringTableSize, dyn_GetStringTable, dyn_GetExpSymTab, dyn_LookupByName, dyn_Relocate, dyn_SetSectionAddr, dyn_AllocSectionMem, dyn_CopySectionContents 1-172 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library dyn_GetSections Obtain a native copy of the section table from a valid dynamically-loadable module. Synopsis #include DYN_RESULT dyn_GetSections(dyn_mem_image *image, dyn_section *sections); Description The dyn_GetSections function accepts a pointer sections to a block of memory, and populates it with a native copy of the section table from the dynamically-loadable module (DLM) pointed to by image. The resulting section table copy is in the native byte order of the target processor. The memory buffer must have been allocated previously, and must be large enough to contain all the section headers for the DLM. Error Conditions The dyn_GetSections function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. The section table will copied to sections. DYN_BAD_PTR The sections or image parameter is NULL. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-173 Documented Library Functions Example #include #include char *get_sec_table(dyn_mem_image *image, int nsecs) { char *space = malloc(nsecs * sizeof(dyn_section)); if (dyn_GetSections(image, space) == DYN_NO_ERROR) return space; return NULL; } See Also dyn_ValidateImage, dyn_GetNumSections, dyn_GetStringTableSize, dyn_GetStringTable, dyn_GetExpSymTab, dyn_LookupByName, dyn_Relocate, dyn_SetSectionAddr, dyn_AllocSectionMem, dyn_CopySectionContents 1-174 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library dyn_GetStringTable Obtain a native copy of the string table of a valid dynamically-loadable module Synopsis #include DYN_RESULT dyn_GetStringTable(dyn_mem_image *image, char *buffer); Description The dyn_GetStringTable function copies the string table from the dynamically-loadable module image to the space pointed to by buffer. The resulting copy is in the native format of the target processor. Error Conditions The dyn_GetStringTable function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. buffer contains a native copy of the string table (one character per location). DYN_BAD_PTR The buffer or image parameter is NULL. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-175 Documented Library Functions Example #include #include char *get_strtab(dyn_mem_image *dlm_info, size_t *nchars) { char *ptr = malloc(nchars); if (dyn_GetStringTable(dlm_info, ptr) == DYN_NO_ERROR) return ptr; return NULL; } See Also dyn_ValidateImage, dyn_GetNumSections, dyn_GetSections, dyn_GetStringTableSize, dyn_GetExpSymTab, dyn_LookupByName, dyn_Relocate, dyn_SetSectionAddr, dyn_AllocSectionMem, dyn_CopySectionContents 1-176 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library dyn_GetStringTableSize Get the size of the string table in a valid dynamically-loadable module Synopsis #include DYN_RESULT dyn_GetStringTableSize(dyn_mem_image *image, size_t *sz); Description The dyn_GetStringTableSize function returns the number of bytes required to hold the string table for the dynamically-loadable module (DLM) pointed to by image. The size is returned in the location pointed to by the sz parameter. In a dynamically-loadable module, the string table contains the names of the various sections in the DLM. It does not contain character strings or other data that constitutes the loadable part of the DLM. Error Conditions The dyn_GetStringTableSize function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. *sz contains the size of the string table. DYN_BAD_PTR The sz or image parameter is NULL. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-177 Documented Library Functions Example #include #include void get_strtab_size(dyn_mem_image *dlm_info) { size_t nchars; if (dyn_GetStringTableSize(dlm_info, &nchars) == DYN_NO_ERROR) printf("There are %d characters in the table\n", nchars); } See Also dyn_ValidateImage, dyn_GetNumSections, dyn_GetSections, dyn_GetStringTable, dyn_GetExpSymTab, dyn_LookupByName, dyn_Relocate, dyn_SetSectionAddr, dyn_AllocSectionMem, dyn_CopySectionContents 1-178 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library dyn_heap_init Initialize a target heap for dynamically-loadable modules Synopsis #include DYN_RESULT dyn_heap_init(dyn_heap *heap, void *base, size_t size, size_t width, size_t align); Description The dyn_heap_init function initializes the heap parameter, so that it contains a description of a region of target memory that can be used to relocate dynamically-loaded code or data. The resulting structure will be suitable for passing to dyn_AddHeap. The heap parameter must point to a dyn_heap structure that is initialized as follows: * base - the address of the first addressable unit in the region of target memory. * size * width - the number of addressable units that can be allocated. Therefore, this should be set to the same value as total_size. - should be set to the number of 8-bit values that can fit into a single location in the target memory. Therefore: 2 for VISA space, 4 for normal data memory, 6 for program memory, and 8 for long-word data memory. Note that only one heap may be specified, for each given width. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-179 Documented Library Functions * - when memory is allocated from this region, the offset into the region will be a multiple of this value. Therefore, this must be 1, 2 or 4, as required for memory alignment. align Error Conditions The dyn_heap_init function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. The dyn_heap structure is now initialized. DYN_BAD_PTR Either image or heap was NULL, or size was zero. DYN_BAD_IMAGE The base pointer was not appropriately aligned for the align parameter. Example #include DYN_RESULT data_heap(dyn_heap *heap) {, static int myspace[50]; return dyn_heap_init(heap, myspace, sizeof(myspace), 4, 2); } See Also dyn_ValidateImage, dyn_GetNumSections, dyn_GetSections, dyn_GetStringTableSize, dyn_GetStringTable, dyn_GetExpSymTab, dyn_LookupByName, dyn_Relocate, dyn_SetSectionAddr, dyn_CopySectionContents, dyn_FreeSectionMem, dyn_AllocSectionMemHeap, malloc 1-180 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library dyn_LookupByName Locate an exported symbol in a dynamically-loadable module Synopsis #include DYN_RESULT dyn_LookupByName(dyn_mem_image *image, const char *name, void *symtab, uint32_t secsize, void **ptr); Description The dyn_LookupByName function searches the exported symbol table of the dynamically-loadable module (DLM) image, looking for a symbol called name. If such a symbol is found, the symbol's address is returned in the location pointed to by ptr. symtab is a pointer to the contents of the DLM's exported symbol table, as previously located via dyn_GetExpSymTab; secsize indicates the section's size. This function may only be called after the DLM has been relocated by calling dyn_Relocate; prior to that point, the exported symbol table's entries are not completely resolved. The name parameter must match the exported symbol exactly. This means that it must also be mangled appropriately for the symbol's namespace. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-181 Documented Library Functions Error Conditions The dyn_LookupByName function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. *ptr contains the address of the symbol, in the relocated image. DYN_BAD_PTR The ptr or image parameter is NULL. DYN_NOT_FOUND The exported symbol table does not contain a symbol whose name exactly matches name. Example #include #include int call_fn(dyn_mem_image *image, void *symtab, uint32_t secsize, const char *fnname) { void *ptr; if (dyn_LookupByName(image, fnname, symtab, secsize, &ptr) == DYN_NO_ERROR) { int (*fnptr)(void) = (int (*)(void))ptr; return (*fnptr)(); } return -1; } 1-182 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also dyn_ValidateImage, dyn_GetNumSections, dyn_GetSections, dyn_GetStringTableSize, dyn_GetStringTable, dyn_GetExpSymTab, dyn_Relocate, dyn_SetSectionAddr, dyn_AllocSectionMem, dyn_CopySectionContents CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-183 Documented Library Functions dyn_RecordRelocOutOfRange Record which relocation cannot be completed, while relocating a dynamically-loadable module Synopsis #include int dyn_RecordRelocOutOfRange(void *ref_addr, uint32_t sym_addr); Description The dyn_RecordRelocOutOfRange function is invoked by dyn_Relocate, if a computed relocation is out of range. It provides an opportunity to make a note of the offending reference. Alternatively, it provides an opportunity to ignore the problem. is the target address of the location being relocated, while is the computed location or value which is being referenced by ref_addr. sym_addr is presented before being manipulated to fit into the field at ref_addr. For example, if ref_addr only references even addresses, the stored value in the field might be shifted down one place; sym_addr represents the value before this shift has happened. ref_addr sym_addr The default implementation of the dynRecordRelocOutOfRange function records both ref_addr and sym_addr, so that they can be retrieved later using dyn_RetrieveRelocOutOfRange. Error Conditions The dyn_RecordRelocOutOfRange function must return a value indicating whether this combination of ref_addr and sym_addr should be considered an error. If the function returns false, then dyn_Relocate will continue its operation. If the function returns true, then dyn_Relocate will abort. 1-184 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Example #include int dyn_RecordRelocOutOfRange(void *ref_addr, uint32_t sym_addr) { /* alternative implementation that ignores all errors */ return 0; } See Also dyn_Relocate, dyn_RetrieveRelocOutOfRange CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-185 Documented Library Functions dyn_Relocate Relocate a dynamically-loadable module Synopsis #include DYN_RESULT dyn_Relocate(dyn_mem_image *image, dyn_section *sections); Description The dyn_Relocate function processes the relocations in a dynamically-loadable module (DLM) once its sections have been copied into local memory. is the DLM, as loaded and validated. sections is a copy of the DLM's section table, as obtained via dyn_GetSections. Before relocation can be performed, space must have been allocated for each of the sections in the file, using dyn_AllocSectionMem, and the sections' contents copied into that space using dyn_CopySectionContents. image Error Conditions The dyn_Relocate function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. All sections were relocated. DYN_BAD_PTR The sections or image parameter is NULL. DYN_NO_SECTION_ADDR There is a section in the DLM which has not had an address allocated, prior to attempting to relocate it. DYN_BAD_RELOC The DLM contains a relocation that is not recognized by the current instance of libdyn. 1-186 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Returned Value Reason DYN_BAD_WIDTH The DLM contains a relocation that references a section with a word size not supported by this instance of libdyn. DYN_NOT_ALIGNED The DLM could not complete relocations because there is a section that is not appropriately aligned for its word size. DYN_OUT_OF_RANGE The DLM could not apply a relocation because the computed value does not fit into the available space. This generally means that the reference and the target of the relocation are too far apart. The function will invoke dyn_RecordRelocOutOfRange to record the details of the failing relocation. These details can be retrieved with dyn_RetrieveRelocOutOfRange. Example #include int reloc_dlm(dyn_mem_image *dlm_info, dyn_section *sections) { if (dyn_Relocate(dlm_info, sections) == DYN_NO_ERROR) return 0; return -1; } See Also dyn_ValidateImage, dyn_GetNumSections, dyn_GetSections, dyn_GetStringTableSize, dyn_GetStringTable, dyn_GetExpSymTab, dyn_LookupByName, dyn_SetSectionAddr, dyn_AllocSectionMem, dyn_CopySectionContents, dyn_RecordRelocOutOfRange, dyn_RetrieveRelocOutOfRange CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-187 Documented Library Functions dyn_RetrieveRelocOutOfRange Retrieve information about a relocation that failed Synopsis #include DYN_RESULT dyn_RetrieveRelocOutOfRange(void **ref_addr, uint32_t *sym_addr); Description The dyn_RetrieveRelocOutOfRange function is used to retrieve information about a failing relocation, if dyn_Relocate returns DYN_OUT_OF_RANGE. The information must first have been saved by dyn_RecordRelocOutOfRange. will be set to the target address of the location that was being relocated, while *sym_addr will be set to the computed location or value that was being referenced by *ref_addr. *ref_addr Error Conditions The dyn_RetrieveRelocOutOfRange function returns a value to indicate the status of its operation, as follows. Returned Value Reason DYN_NO_ERROR Success. *ref_addr and *sym_addr have been updated. DYN_BAD_PTR Either ref_addr or sym_addr was NULL. 1-188 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Example #include void reloc_dlm(dyn_mem_image *dlm_info, dyn_section *sections) { if (dyn_Relocate(dlm_info, sections) == DYN_OUT_OF_RANGE && dyn_RetrieveRelocOutOfRange(&ref, &sym) == DYN_NO_ERROR) printf("Relocation %p -> %p failed\n", ref, sym); } See Also dyn_Relocate, dyn_RecordRelocOutOfRange CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-189 Documented Library Functions dyn_RewriteImageToFile Write a dynamically-loadable module back to a file, after relocation Synopsis #include DYN_RESULT dyn_RewriteImageToFile(dyn_mem_image *image, dyn_section *sections, size_t num_sections, FILE *outf); Description The dyn_RewriteImageToFile function writes the contents of a dynamically-loadable module (DLM) to the specified output stream outf, after relocation has taken place. is the DLM, as loaded, validated and relocated. sections is a copy of the DLM's section table, as obtained via dyn_GetSections. image Error Conditions The dyn_RewriteImageToFile function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. All sections were written back to the output stream without error. DYN_BAD_WRITE One of the output operations on the output stream did not succeed. DYN_NO_MEM There was insufficient memory to obtain a local working copy of some data. 1-190 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Returned Value Reason DYN_BAD_PTR The image parameter was NULL, or a there is a corrupt internal memory reference. DYN_NOT_FOUND Not all sections could be located, suggesting that the num_sections parameter is incorrect. Example #include int reloc_dlm(dyn_mem_image *dlm, dyn_section *secs, size_t nsecs, FILE *fp) { if (dyn_Relocate(dlm, secs) == DYN_NO_ERROR && dyn_RewriteImageToFile(dlm, secs, nsecs, fp) == DYN_NO_ERROR) return 0; return -1; } See Also dyn_ValidateImage, dyn_GetNumSections, dyn_GetSections, dyn_GetStringTableSize, dyn_GetStringTable, dyn_GetExpSymTab, dyn_LookupByName, dyn_SetSectionAddr, dyn_AllocSectionMem, dyn_CopySectionContents CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-191 Documented Library Functions dyn_SetSectionAddr Set the local address for a section in a dynamically-loadable module Synopsis #include DYN_RESULT dyn_SetSectionAddr(dyn_mem_image *image, dyn_section *sections, size_t secnum, void *addr); Description The dyn_SetSectionAddr function sets the local address for a given section within a dynamically-loadable module (DLM). image is the DLM, validated by dyn_ValidateImage. sections is a native copy of the DLM's section table, obtained by dyn_GetSections. secnum is the number for the section for which to set the address. addr is the local address. In this context, "setting the address" means informing the DLM that address addr is a suitable address at which section secnum may reside after relocation; if dyn_CopySectionContents is called, the section's contents will be copied to addr, so sufficient space must have previously been reserved at that address. 1-192 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Error Conditions The dyn_SetSectionAddr function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. The address has been recorded within the native section table copy. DYN_BAD_PTR The sections or image parameter is NULL, or there is no section secnum. This value is also returned if the section already has an address assigned, or it has already been relocated. Example #include int set_addr(dyn_mem_image *image, dyn_section *secs, size_t num, void *ptr) { if (dyn_SetSectionAddr(image, secs, num, ptr) == DYN_NO_ERROR) return 0; return -1; } See Also dyn_ValidateImage, dyn_GetNumSections, dyn_GetSections, dyn_GetStringTableSize, dyn_GetStringTable, dyn_GetExpSymTab, dyn_LookupByName, dyn_Relocate, dyn_AllocSectionMem, dyn_CopySectionContents CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-193 Documented Library Functions dyn_SetSectionMem Specify the target address of a dynamically-loadable section Synopsis #include DYN_RESULT dyn_SetSectionMem(dyn_mem_image *image, dyn_section *sections, size_t secnum, uint32_t taddr, dyn_section_mem **memptr); Description The dyn_SetSectionMem function creates internal house-keeping memory for a given section within a dynamically-loadable module (DLM), and records the target address at which the section will reside. image is the DLM, validated by dyn_ValidateImage. sections is a native copy of the DLM's section table, obtained by dyn_GetSections. secnum is the number for the section for which to set the address. taddr is the target address. In this context, the target address refers to the address at which the section will begin, when relocated. The function will create a dyn_section_mem structure, pointed to by *memptr, which can be passed to dyn_SetSectionAddr. 1-194 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Error Conditions The dyn_SetSectionMem function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. The address has been recorded within the native section table copy. DYN_BAD_PTR The image, sections or memptr parameter is NULL. DYN_BAD_IMAGE There is no section secnum. DYN_NO_MEM There is insufficient memory to allocate the internal house-keeping structures. Example #include dyn_section_mem *set_addr(dyn_mem_image *image, dyn_section *secs, size_t num, uint32_t addr) { dyn_section_mem *mem = 0; if (dyn_SetSectionMem(image, secs, num, addr, &mem) == DYN_NO_ERROR) return 0; return mem; } See Also dyn_ValidateImage, dyn_GetNumSections, dyn_GetSections, dyn_GetStringTableSize, dyn_GetStringTable, dyn_GetExpSymTab, dyn_LookupByName, dyn_Relocate, dyn_AllocSectionMem, dyn_CopySectionContents CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-195 Documented Library Functions dyn_ValidateImage Verify a memory buffer contains a valid dynamically-loadable module Synopsis #include DYN_RESULT dyn_ValidateImage(void *ptr, size_t len, dyn_mem_image *image); Description The dyn_ValidateImage function accepts a pointer to a block of memory, and performs various checks to determine whether the memory contains a validate dynamically-loadable module (DLM), as produced by elf2dyn. The memory buffer is pointed to by ptr, and must be at least len characters in size. If the buffer does contain a valid DLM, the function will populate the structure pointed to by image; the resulting image pointer will be suitable for passing to other DLM-handling functions. Error Conditions The dyn_ValidateImage function returns a status value indicating success, or the reason for failure, as follows. Returned Value Reason DYN_NO_ERROR Success. The buffer contains a valid DLM. DYN_BAD_PTR The ptr or image parameter is NULL. DYN_TOO_SMALL The memory buffer as described by ptr/len is too small to contain any DLM, or the DLM's sections/relocations exceed the buffer. DYN_BAD_IMAGE The image does not have the right magic number, or offsets within the image are nonsensical. 1-196 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Returned Value Reason DYN_BAD_VERSION The DLM's version number is not a version supported by this instance of libdyn. DYN_BAD_FAMILY The DLM is for a processor family not recognized by this instance of libdyn. Example #include #include static dyn_mem_image dlm_info; int check_dlm(FILE *fp, char *buf, size_t maxlen) { size_t len = fread(buf, 1, maxlen, fp); if (dyn_ValidateImage(buf, len, &dlm_info) == DYN_NO_ERROR) return 0; return -1; } See Also dyn_GetNumSections, dyn_GetSections, dyn_GetStringTableSize, dyn_GetStringTable, dyn_GetExpSymTab, dyn_LookupByName, dyn_Relocate, dyn_SetSectionAddr, dyn_AllocSectionMem, dyn_CopySectionContents CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-197 Documented Library Functions exit Normal program termination Synopsis #include void exit (int status); Description The exit function causes normal program termination. The functions registered by the atexit function are called in reverse order of their registration and the processor is put into the IDLE state. The status argument is stored in register R0, and control is passed to the label ___lib_prog_term, which is defined in the run-time startup file. Error Conditions None. Example #include exit (EXIT_SUCCESS); See Also abort, atexit 1-198 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library exp Exponential Synopsis #include float expf (float x); double exp (double x); long double expd (long double x); Description The exponential functions compute the exponential value e to the power of their argument. Error Conditions The input argument x for expf must be in the domain [-87.33, 88.72] and the input argument for expd must be in the domain [-708.2, 709.1]. The functions return HUGE_VAL if x is greater than the domain and 0.0 if x is less than the domain. Example #include double y; float x; y = exp (1.0); /* y = 2.71828 */ x = expf (1.0); /* x = 2.71828 */ See Also log, pow CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-199 Documented Library Functions fabs Absolute value Synopsis #include float fabsf (float x); double fabs (double x); long double fabsd (long double x); Description The fabs functions return the absolute value of the argument x. Error Conditions None. Example #include double y; float x; y = fabs (-2.3); /* y = 2.3 */ y = fabs (2.3); /* y = 2.3 */ x = fabsf (-5.1); /* x = 5.1 */ See Also abs, absfx, labs, llabs 1-200 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library fclose Close a stream Synopsis #include int fclose(FILE *stream); Description The fclose function flushes stream and closes the associated file. The flush will result in any unwritten buffered data for the stream to be written to the file, with any unread buffered data being discarded. If the buffer associated with stream was allocated automatically it will be deallocated. The fclose function will return 0 on successful completion. Error Conditions If the fclose function is not successful it returns EOF. Example #include void example(char* fname) { FILE *fp; fp = fopen(fname, "w+"); /* Do some operations on the file */ fclose(fp); } CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-201 Documented Library Functions See Also fopen 1-202 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library feof Test for end of file Synopsis #include int feof(FILE *stream); Description The feof function tests whether or not the file identified by stream has reached the end of the file. The routine returns 0 if the end of the file has not been reached and a non-zero result of the end of file has been reached. Error Conditions None. Example #include void print_char_from_file(FILE *fp) { /* printf out each character from a file until EOF */ while (!feof(fp)) printf("%c", fgetc(fp)); printf("\n"); } See Also clearerr, ferror CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-203 Documented Library Functions ferror Test for read or write errors Synopsis #include int ferror(FILE *stream); Description The ferror function tests whether an uncleared error has occurred while accessing stream. If there are no errors then the function will return zero, otherwise it will return a non-zero value. does not examine whether the file identified by The ferrorhasfunction reached the end of the file. stream Error Conditions None. Example #include void test_for_error(FILE *fp) { if (ferror(fp)) printf("Error with read/write to stream\n"); else printf("read/write to stream OKAY\n"); } See Also clearerr, feof 1-204 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library fflush Flush a stream Synopsis #include int fflush(FILE *stream); Description The fflush function causes any unwritten data for stream to be written to the file. If stream is a NULL pointer, fflush performs this flushing action on all streams. Upon successful completion the fflush function returns zero. Error Conditions If fflush is unsuccessful, the EOF value is returned. Example #include void flush_all_streams(void) { fflush(NULL); } See Also fclose CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-205 Documented Library Functions fgetc Get a character from a stream Synopsis #include int fgetc(FILE *stream); Description The fgetc function obtains the next character from the input stream pointed to by stream, converts it from an unsigned char to an int and advances the file position indicator for the stream. If there are no errors, then fgetc will return the next character as the function result. Error Conditions If the fgetc function is unsuccessful, EOF is returned. Example #include char use_fgetc(FILE *fp) { char ch; if ((ch = fgetc(fp)) == EOF) { printf("Read End-of-file\n") return 0; } else { return ch; } } 1-206 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also getc CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-207 Documented Library Functions fgetpos Record the current position in a stream Synopsis #include int fgetpos(FILE *stream, fpos_t *pos); Description The fgetpos function stores the current value of the file position indicator for the stream pointed to by stream in the file position type object pointed to by pos. The information generated by fgetpos in pos can be used with the fsetpos function to return the file to this position. Upon successful completion the fgetpos function will return 0. Error Conditions If fgetpos is unsuccessful, the function will return a non-zero value. Example #include void aroutine(FILE *fp, char *buffer) { fpos_t pos; /* get the current file position */ if (fgetpos(fp, &pos)!= 0) { printf("fgetpos failed\n"); return; } /* write the buffer to the file */ (void) fprintf(fp, "%s\n", buffer); /* reset the file position to the value before the write */ 1-208 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library if (fsetpos(fp, &pos) != 0) { printf("fsetpos failed\n"); } } See Also fsetpos, ftell, fseek, rewind CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-209 Documented Library Functions fgets Get a string from a stream Synopsis #include char *fgets(char *s, int n, FILE *stream); Description The fgets function reads characters from stream into the array pointed to by s. The function will read a maximum of one less character than the value specified by n, although the get will also end if either a NEWLINE character or the end-of-file marker are read. The array s will have a NUL character written at the end of the string that has been read. Upon successful completion the fgets function will return s. Error Conditions If fgets is unsuccessful, the function will return a NULL pointer. Example #include char buffer[20]; void read_into_buffer(FILE *fp) { char *str; str = fgets(buffer, sizeof(buffer), fp); if (str == NULL) { 1-210 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library printf("Either read failed or EOF encountered\n"); } else { printf("filled buffer with %s\n", str); } } See Also fgetc, getc, gets CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-211 Documented Library Functions fileno Get the file descriptor for a stream Synopsis #include int fileno(FILE *stream); Description The fileno function returns the file descriptor for a stream. The file descriptor is an opaque value used by the extensible device driver interface to represent the open file. The resulting value may only be used as a parameter to other functions that accept file descriptors. Error Conditions The fileno function returns -1 if it detects that stream is not valid or is not open. If successful, it returns a positive value. Example #include int apply_control_cmd(FILE *fp, int cmd, int val) { int fildes = fileno(fp); return ioctl(fildes, cmd, val); } See Also fopen, ioctl 1-212 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library floor Floor Synopsis #include float floorf (float x); double floor (double x); long double floord (long double x); Description The floor functions return the largest integral value that is not greater than their argument. Error Conditions None. Example #include double y; float z; y = floor (1.25); /* y = 1.0 y = floor (-1.25); /* y = -2.0 */ */ z = floorf (10.1); /* z = 10.0 */ See Also ceil CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-213 Documented Library Functions fmod Floating-point modulus Synopsis #include float fmodf (float x, float y); double fmod (double x, double y); long double fmodd (long double x, long double y); Description The fmod functions compute the floating-point remainder that results from dividing the first argument by the second argument. The result is less than the second argument and has the same sign as the first argument. If the second argument is equal to zero, the fmod functions return zero. Error Conditions None. Example #include double y; float x; y = fmod (5.0, 2.0); /* y = 1.0 */ x = fmodf (4.0, 2.0); /* x = 0.0 */ See Also div, ldiv, modf 1-214 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library fopen Open a file Synopsis #include FILE *fopen(const char *filename, const char *mode); Description The fopen function initializes the data structures that are required for reading or writing to a file. The file's name is identified by filename, with the access type required specified by the string mode. Valid selections for mode are specified below. If any other mode specification is selected then the behavior is undefined. mode Selection r Open text file for reading. This operation fails if the file has not previously been created. w Open text file for writing. If the filename already exists then it will be truncated to zero length with the write starting at the beginning of the file. If the file does not already exist then it is created. a Open a text file for appending data. All data will be written to the end of the file specified. r+ As r with the exception that the file can also be written to. w+ As w with the exception that the file can also be read from. a+ As a with the exception that the file can also be read from any position within the file. Data is only written to the end of the file. rb As r with the exception that the file is opened in binary mode. wb As w with the exception that the file is opened in binary mode. ab As a with the exception that the file is opened in binary mode. r+b/rb+ Open file in binary mode for both reading and writing. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-215 Documented Library Functions mode Selection w+b/wb+ Create or truncate to zero length a file for both reading and writing. a+b/ab+ As a+ with the exception that the file is opened in binary mode. If the call to the fopen function is successful a pointer to the object controlling the stream is returned. Error Conditions If the fopen function is not successful a NULL pointer is returned. Example #include FILE *open_output_file(void) { /* Open file for writing as binary */ FILE *handle = fopen("output.dat", "wb"); return handle; } See Also fclose, fflush, freopen 1-216 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library fprintf Print formatted output Synopsis #include int fprintf(FILE *stream, const char *format, /*args*/ ...); Description The fprintf function places output on the named output stream. The string pointed to by format specifies how the arguments are converted for output. The format string can contain zero or more conversion specifications, each beginning with the % character. The conversion specification itself follows the % character and consists of one or more of the following sequence: * Flag - optional characters that modifies the meaning of the conversion. * Width - optional numeric value (or *) that specifies the minimum field width. * Precision - optional numeric value that gives the minimum number of digits to appear. * Length - optional modifier that specifies the size of the argument. * Type - character that specifies the type of conversion to be applied. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-217 Documented Library Functions The flag characters can be in any order and are optional. The valid flags are described in Table 1-35. Table 1-35. Valid Flags for fprintf Function Flag Field - Left justify the result within the field. The result is right-justified by default. + Always begin a signed conversion with a plus or minus sign. By default only negative values will start with a sign. space Prefix a space to the result if the first character is not a sign and the + flag has not also been specified. # The result is converted to an alternative form depending on the type of conversion: o : If the value is not zero it is preceded with 0. x : If the value is not zero it is preceded with 0x. X : If the value is not zero it is preceded with 0X. a A e E f F: Always generate a decimal point. g G : as E except trailing zeros are not removed. 0 (zero) Specifies an alternative to space padding. Leading zeroes will be used as necessary to pad a field to the specified field width, the leading zeroes will follow any sign or specification of a base. The flag will be ignored if it appears with a `-' flag or if it is used in a conversion specification that uses a precision and one of the conversions a, A, d, i, o, u, x or X. The 0 flag may be used with the a, A, d, i, o, u, x, X, e, E, f, g and G conversions. If a field width is specified, the converted value is padded with spaces to the specified width if the converted value contains fewer characters than the width. Normally spaces will be used to pad the field on the left, but padding on the right will be used if the `-' flag has been specified. The `0' flag may be used as an alternative to space padding; see the description of the flag field above. The width may also be specified as a `*', which indicates that the current argument in the call to fprintf is an int that defines the value of the width. If the value is negative then it is interpreted as a `-' flag and a positive field width. 1-218 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library The optional precision value always begins with a period (.) and is followed either by an asterisk (*) or by a decimal integer. An asterisk (*) indicates that the precision is specified by an integer argument preceding the argument to be formatted. If only a period is specified, a precision of zero will be assumed. The precision value has differing effects depending on the conversion specifier being used: * For A, a specifies the number of digits after the decimal point. If the precision is zero and the # flag is not specified no decimal point will be generated. * For d,i,o,u,x,X specifies the minimum number of digits to appear, defaulting to 1. * For f,F,E,e,r,R specifies the number of digits after the decimal point character, the default being 6. If the # specifier is present with a zero precision then no decimal point will be generated. * For g, G specifies the maximum number of significant digits. * For s specifies the maximum number of characters to be written. The length modifier (Table 1-36) can optionally be used to specify the size of the argument. The length modifiers should only precede one of the d, i, o, u, x, X, r, R or n conversion specifiers unless other conversion specifiers are detailed. Table 1-36. Length Modifiers for fprintf Function Length Action h The argument should be interpreted as a short int. If preceding the r or R conversion specifier, the argument is interpreted as short fract or unsigned short fract. l The argument should be interpreted as a long int. If preceding the r or R conversion specifier, the argument is interpreted as long fract or unsigned long fract CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-219 Documented Library Functions Table 1-36. Length Modifiers for fprintf Function (Cont'd) Length Action ll The argument should be interpreted as a long long int. L The argument should be interpreted as a long double argument. This length modifier should precede one of the a, A, e, E, f, F, g, or G conversion specifiers. Note that this length modifier is only valid if -double-size-64 is selected. If -double-size-32 is selected no conversion will occur, with the corresponding argument being consumed. Table 1-37 contains definitions of the valid conversion specifiers that define the type of conversion to be applied. Table 1-37. Valid Conversion Specifier Definitions for fprintf Function Specifier Conversion a, A floating-point, hexadecimal notation c character d, i signed decimal integer e, E floating-point, scientific notation (mantissa/exponent) f, F floating-point, decimal notation g, G convert as e, E or f, F n pointer to signed integer to which the number of characters written so far will be stored with no other output o unsigned octal p pointer to void r signed fract R unsigned fract s string of characters u unsigned integer x, X unsigned hexadecimal notation % print a % character with no argument conversion 1-220 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library The a|A conversion specifier converts to a floating-point number with the notational style [-]0xh.hhhhd where there is one hexadecimal digit before the period. The a|A conversion specifiers always contain a minimum of one digit for the exponent. The e|E conversion specifier converts to a floating-point number notational style [-]d.dddedd. The exponent always contains at least two digits. The case of the e preceding the exponent will match that of the conversion specifier. The f|F conversion specifies to convert to decimal notation [-]d.dddddd. The g|G conversion specifier converts as e|E or f|F specifiers depending on the value being converted. If the value being converted is less than -4 or greater than or equal to the precision then e|E conversions will be used, otherwise f|F conversions will be used. For all of the a, A, e, E, f, F, g and G specifiers an argument that represents infinity is displayed as Inf. For all of the a, A, e, E, f, F, g and G specifiers an argument that represents a NaN result is displayed as NaN. The r|R conversion specifiers convert a fixed-point value to decimal notation [-]d.ddd if you are linking with the fixed-point I/O library using the -flags-link -MD__LIBIO_FX switch. Otherwise they will convert a fixed-point value to hexadecimal. The fprintf function returns the number of characters printed. Error Conditions If the fprintf function is unsuccessful, a negative value is returned. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-221 Documented Library Functions Example #include void fprintf_example(void) { char *str = "hello world"; /* Output to stdout is " +1 +1." */ fprintf(stdout, "%+5.0f%+#5.0f\n", 1.234, 1.234); /* Output to stdout is "1.234 1.234000 1.23400000" */ fprintf(stdout, "%.3f %f %.8f\n", 1.234, 1.234, 1.234); /* Output to stdout is "justified: left:5 right: 5" */ fprintf(stdout, "justified:\nleft:%-5dright:%5i\n", 5, 5); /* Output to stdout is "90% of test programs print hello world" */ fprintf(stdout, "90%% of test programs print %s\n", str); /* Output to stdout is "0.0001 1e-05 100000 1E+06" */ fprintf(stdout, "%g %g %G %G\n", 0.0001, 0.00001, 1e5, 1e6); } See Also printf, snprintf, vfprintf, vprintf, vsnprintf, vsprintf 1-222 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library fputc Put a character on a stream Synopsis #include int fputc(int ch, FILE *stream); Description The fputc function writes the argument ch to the output stream pointed to by stream and advances the file position indicator. The argument ch is converted to an unsigned char before it is written. If the fputc function is successful then it will return the value that was written to the stream. Error Conditions If the fputc function is not successful EOF is returned. Example #include void fputc_example(FILE* fp) { /* put the character 'i' to the stream pointed to by fp */ int res = fputc('i', fp); if (res != 'i') printf("fputc failed\n"); } See Also putc CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-223 Documented Library Functions fputs Put a string on a stream Synopsis #include int fputs(const char *string, FILE *stream); Description The fputs function writes the string pointed to by string to the output stream pointed to by stream. The NULL terminating character of the string will not be written to stream. If the call to fputs is successful, the function returns a non-negative value. Error Conditions The fputs function will return EOF if a write error occurred. Example #include void fputs_example(FILE* fp) { /* put the string "example" to the stream pointed to by fp */ char *example = "example"; int res = fputs(example, fp); if (res == EOF) printf("fputs failed\n"); } See Also puts 1-224 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library fread Buffered input Synopsis #include size_t fread(void *ptr, size_t size, size_t n, FILE *stream); Description The fread function reads into an array pointed to by ptr up to a maximum of n items of data from stream, where each item of data is of length size. It stops reading data if an EOF or error condition is encountered while reading from stream, or if n items have been read. It advances the data pointer in stream by the number of characters read. It does not change the contents of stream. The fread function returns the number of items read, this may be less than n if there is insufficient data on the external device to satisfy the read request. If size or n is zero, then fread will return zero and does not affect the state of stream. When the stream has been opened as a binary stream, the Analog Devices I/O library may choose to bypass the I/O buffer and transmit data from an external device directly into the program, particularly when the buffer size (as defined by the macro BUFSIZ in the stdio.h header file, or controlled by the function setvbuf) is smaller than the number of characters to be transferred. Normally, binary streams are a bit-exact mirror image of the processor's memory such that data that is written out to a binary stream can be later read back unmodified. The size of a binary file on SHARC architecture is therefore normally a multiple of 32-bit words. When the size of a file is not a multiple of four, fread will behave as if the file was padded out by a sufficient number of trailing null characters to bring the size of the file up to the next multiple of 32-bit words. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-225 Documented Library Functions Error Conditions If an error occurs, fread returns zero and sets the error indicator for stream. Example #include int buffer[100]; int fill_buffer(FILE *fp) { int read_items; /* Read from file pointer fp into array buffer */ read_items = fread(&buffer, sizeof(int), 100, fp); if (read_items < 100) { if (ferror(fp)) printf("fill_buffer failed with an I/O error\n"); else if (feof(fp)) printf("fill_buffer failed with EOF\n"); else printf("fill_buffer only read %d items\n",read_items); } return read_items; } See Also ferror, fgetc, fgets, fscanf 1-226 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library free Deallocate memory Synopsis #include void free (void *ptr); Description The free function deallocates a pointer previously allocated to a range of memory to the free memory heap. If the pointer was not previously allocated by calloc, malloc, realloc, heap_calloc, heap_malloc, or heap_realloc, the behavior is undefined. The free function returns the allocated memory to the heap from which it was allocated. Error Conditions None. Example #include char *ptr; ptr = malloc (10); /* Allocate 10 words from heap */ free (ptr); /* Return space to free heap */ See Also calloc, heap_calloc, heap_free, heap_lookup, heap_malloc, heap_realloc, malloc, realloc, heap_space_unused CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-227 Documented Library Functions freopen Open a file using an existing file descriptor Synopsis #include FILE *freopen(const char *fname, const char *mode, FILE *stream); Description The freopen function opens the file specified by fname and associates it with the stream pointed to by stream. The mode argument has the same effect as described in fopen. (See fopen for more information on the mode argument.) Before opening the new file the freopen function will first attempt to flush the stream and close any file descriptor associated with stream. Failure to flush or close the file successfully is ignored. Both the error and EOF indicators for stream are cleared. The original stream will always be closed regardless of whether the opening of the new file is successful or not. Upon successful completion the freopen function returns the value of stream. Error Conditions If freopen is unsuccessful, a NULL pointer is returned. 1-228 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Example #include void freopen_example(FILE* fp) { FILE *result; char *newname = "newname"; /* reopen existing file pointer for reading file "newname" */ result = freopen(newname, "r", fp); if (result == fp) printf("%s reopened for reading\n", newname); else printf("freopen not successful\n"); } See Also fclose, fopen CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-229 Documented Library Functions frexp Separate fraction and exponent Synopsis #include float frexpf (float x, int *expptr); double frexp (double x, int *expptr); long double frexpd (long double x, int *expptr); Description The frexp functions separate a floating-point input into a normalized fraction and a (base 2) exponent. The functions return a fraction in the interval [1/2, 1), and store a power of 2 in the integer pointed to by the second argument. If the input is zero, then both the fraction and the exponent is set to zero. Error Conditions None. Example #include double y; float x; int exponent; y = frexp (2.0, &exponent); /* y = 0.5, exponent = 2 */ x = frexpf (4.0, &exponent); /* x = 0.5, exponent = 3 */ 1-230 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also modf CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-231 Documented Library Functions fscanf Read formatted input Synopsis #include int fscanf(FILE *stream, const char *format, /* args */...); Description The fscanf function reads from the input file stream, interprets the inputs according to format and stores the results of the conversions (if any) in its arguments. The format is a string containing the control format for the input with the following arguments as pointers to the locations where the converted results are written. The string pointed to by format specifies how the input is to be parsed and, possibly, converted. It may consist of whitespace characters, ordinary characters (apart from the % character), and conversion specifications. A sequence of whitespace characters causes fscanf to continue to parse the input until either there is no more input or until it find a non-whitespace character. If the format specification contains a sequence of ordinary characters then fscanf will continue to read the next characters in the input stream until the input data does not match the sequence of characters in the format. At this point fscanf will fail, and the differing and subsequent characters in the input stream will not be read. The % character in the format string introduces a conversion specification. A conversion specification has the following form: % [*] [width] [length] type A conversion specification always starts with the % character. It may optionally be followed by an asterisk (*) character, which indicates that the result of the conversion is not to be saved. In this context the asterisk character is known as the assignment-suppressing character. The optional 1-232 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library token width represents a non-zero decimal number and specifies the maximum field width. fscanf will not read any more than width characters while performing the conversion specified by type. The length token can be used to define a length modifier. The length modifier (Table 1-38) can be used to specify the size of the argument. The length modifiers should only precede one of the d, i, o, u, x, X, r, R or n conversion specifiers unless other conversion specifiers are detailed. Table 1-38. Length Modifiers for fscanf Function Length Action h The argument should be interpreted as a short int. If preceding the r or R conversion specifier, the argument is interpreted as short fract or unsigned short fract. hh The argument should be interpreted as a char. j The argument should be interpreted as intmax_t or uintmax_t. l The argument should be interpreted as a long int. If preceding the r or R conversion specifier, the argument is interpreted as long fract or unsigned long fract. ll The argument should be interpreted as a long long int. L The argument should be interpreted as a long double argument. This length modifier should precede one of the a, A, e, E, f, F, g, or G conversion specifiers. t The argument should be interpreted as ptrdiff_t. z The argument should be interpreted as size_t. The , , , and size specifiers are defined in the C99 (ISO/IEC 9899:1999) standard. hh j t z CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-233 Documented Library Functions A definition of the valid conversion specifier characters that specify the type of conversion to be applied can be found in Table 1-39. Table 1-39. Valid Conversion Specifier Definitions for fscanf Function Specifier Conversion a, A, e, E, f, F, g, G floating point, optionally preceded by a sign and optionally followed by an e or E character c single character, including whitespace d signed decimal integer with optional sign i signed integer with optional sign n no input is consumed. The number of characters read so far will be written to the corresponding argument. This specifier does not affect the function result returned by fscanf o unsigned octal p pointer to void r signed fract with optional sign R unsigned fract s string of characters up to a whitespace character u unsigned decimal integer x, X hexadecimal integer with optional sign [ a non-empty sequence of characters referred to as the scanset % a single % character with no conversion or assignment The [ conversion specifier should be followed by a sequence of characters, referred to as the scanset, with a terminating ] character and so will take the form [scanset]. The conversion specifier copies into an array which is the corresponding argument until a character that does not match any of the scanset is read. If the scanset begins with a ^ character then the scanning will match against characters not defined in the scanset. If the scanset is to include the ] character then this character must immediately follow the [ character or the ^ character if specified. 1-234 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Each input item is converted to a type appropriate to the conversion character, as specified in the table above. The result of the conversion is placed into the object pointed to by the next argument that has not already been the recipient of a conversion. If the suppression character has been specified then no data shall be placed into the object with the next conversion using the object to store its result. Note that the r and R format specifiers are only supported when linking with the fixed-point I/O library using -flags-link -MD__LIBIO_FX. The fscanf function returns the number of items successfully read. Error Conditions If the fscanf function is not successful before any conversion then EOF is returned. Example #include void fscanf_example(FILE *fp) { short int day, month, year; float f1, f2, f3; char string[20]; /* Scan a date with any separator, eg, 1-1-2006 or 1/1/2006 */ fscanf (fp, "%hd%*c%hd%*c%hd", &day, &month, &year); /* Scan float values separated by "abc", for example 1.234e+6abc1.234abc234.56abc */ fscanf (fp, "%fabc%gabc%eabc", &f1, &f2, &f3); CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-235 Documented Library Functions /* For input "alphabet", string will contain "a" */ writ(fp, "%[aeiou]", string); /* For input "drying", string will contain "dry" */ fscanf (fp, "%[^aeiou]", string); } See Also scanf, sscanf 1-236 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library fseek Reposition a file position indicator in a stream Synopsis #include int fseek(FILE *stream, long offset, int whence); Description The fseek function sets the file position indicator for the stream pointed to by stream. The position within the file is calculated by adding the offset to a position dependent on the value of whence. The valid values and effects for whence are as follows. whence Effect SEEK_SET Set the position indicator to be equal to offset characters from the beginning of stream. SEEK_CUR Set the new position indicator to current position indicator for stream plus offset. SEEK_END Set the position indicator to EOF plus offset. Using fseek to position a text stream is only valid if either offset is zero, or if whence is SEEK_SET and offset is a value that was previously returned by ftell. For binary streams the offset is measured in addressable units of memory, which on SHARC is 32-bit words. within a file that has been opened as a text stream is Positioning only supported by the libraries that Analog Devices supply if the lines within the file are terminated by the character sequence \r\n. A successful call to fseek will clear the EOF indicator for stream and undoes any effects of ungetc on stream. If the stream has been opened as a update stream, then the next I/O operation may be either a read request or a write request. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-237 Documented Library Functions Error Conditions If the fseek function is unsuccessful, a non-zero value is returned. Example #include long fseek_and_ftell(FILE *fp) { long offset; /* seek to 20 characters offset from given file pointer */ if (fseek(fp, 20, SEEK_SET) != 0) { printf("fseek failed\n"); return -1; } /* Now use ftell to get the offset value back */ offset = ftell(fp); if (offset == -1) printf("ftell failed\n"); if (offset == 20) printf("ftell and fseek work\n"); return offset; } See Also fflush, ftell, ungetc 1-238 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library fsetpos Reposition a file pointer in a stream Synopsis #include int fsetpos(FILE *stream, const fpos_t *pos); Description The fsetpos function sets the file position indicator for stream, using the value of the object pointed to by pos. The value pointed to by pos must be a value obtained from an earlier call to fgetpos on the same stream. within a file that has been opened as a text stream is Positioning only supported by the libraries that Analog Devices supply if the lines within the file are terminated by the character sequence \r\n. A successful call to fsetpos function clears the EOF indicator for stream and undoes any effects of ungetc on the same stream. The fsetpos function returns zero if it is successful. Error Conditions If the fsetpos function is unsuccessful, the function returns a non-zero value. Example See fgetpos for an example. See Also fgetpos, ftell, rewind, ungetc CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-239 Documented Library Functions ftell Obtain current file position Synopsis #include long int ftell(FILE *stream); Description The ftell function obtains the current position for a file identified by stream. If stream is a text stream, then the information in the position indicator is unspecified information, usable by fseek for determining the file position indicator at the time of the ftell call. If stream is a binary stream, then ftell returns the current position as an offset from the start of the file. As binary streams are normally bit-exact images of the processor's memory, the offset returned is in addressable units of memory that, on a SHARC processor, is 32-bit words. within a file that has been opened as a text stream is Positioning only supported by the libraries that Analog Devices supply if the lines within the file are terminated by the character sequence \r\n. If successful, the ftell function returns the current value of the file position indicator on the stream. Error Conditions If the ftell function is unsuccessful, a value of -1 is returned. Example See fseek for an example. 1-240 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also fseek CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-241 Documented Library Functions fwrite Buffered output Synopsis #include size_t fwrite(const void *ptr, size_t size, size_t n, FILE *stream); Description The fwrite function writes to the output stream up to n items of data from the array pointed by ptr. An item of data is defined as a sequence of characters of size size. The write will complete once n items of data have been written to the stream. The file position indicator for stream is advanced by the number of characters successfully written. When the stream has been opened as a binary stream, the Analog Devices I/O library may choose to bypass the I/O buffer and transmit data from the program directly to the external device, particularly when the buffer size (as defined by the macro BUFSIZ in the stdio.h header file, or controlled by the function setvbuf) is smaller than the number of characters to be transferred. If successful then the fwrite function will return the number of items written. Error Conditions If the fwrite function is unsuccessful, it will return the number of elements successfully written which will be less than n. 1-242 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Example #include char* message="some text"; void write_text_to_file(void) { /* Open "file.txt" for writing */ FILE* fp = fopen("file.txt", "w"); int res, message_len = strlen(message); if (!fp) { printf("fopen was not successful\n"); return; } res = fwrite(message, sizeof(char), message_len, fp); if (res != message_len) printf("fwrite was not successful\n"); } See Also fread CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-243 Documented Library Functions fxbits Bitwise integer to fixed-point to conversion Synopsis #include short fract hrbits(int_hr_t b); fract rbits(int_r_t b); long fract lrbits(int_lr_t b); unsigned short fract uhrbits(uint_uhr_t b); unsigned fract urbits(uint_ur_t b); unsigned long fract ulrbits(uint_ulr_t b); Description Given an integer operand, the fxbits family of functions return the integer value divided by 2F, where F is the number of fractional bits in the result fixed-point type. This is equivalent to the bit-pattern of the integer value held in a fixed-point type. Error Conditions None. If the input integer value does not fit in the number of bits of the fixed-point result type, the result is saturated to the largest or smallest fixed-point value. Example #include unsigned long fract ulr; ulr = ulrbits(0x20000000); /* ulr == 0.125ulr */ See Also bitsfx 1-244 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library fxdivi Division of integer by integer to give fixed-point result Synopsis #include fract rdivi(int numer, int denom); long fract lrdivi(long int numer, long int denom); unsigned fract urdivi(unsigned int numer, unsigned int denom); unsigned long fract ulrdivi(unsigned long int numer, unsigned long int denom); Description Given an integer numerator and denominator, the fxdivi family of functions computes the quotient and returns the closest fixed-point value to the result. Error Conditions The fxdivi function has undefined behavior if the denominator is zero. Example #include unsigned long fract ulquo; ulquo = ulrdivi(1, 8); /* ulquo == 0.125ulr */ See Also div, divifx, idivfx, ldiv, lldiv CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-245 Documented Library Functions getc Get a character from a stream Synopsis #include int getc(FILE *stream); Description The getc function is equivalent to fgetc. The getc function obtains the next character from the input stream pointed to by stream, converts it from an unsigned char to an int and advances the file position indicator for the stream. Upon successful completion the getc function will return the next character from the input stream pointed to by stream. Error Conditions If the getc function is unsuccessful, EOF is returned. Example #include char use_getc(FILE *fp) { char ch; if ((ch = getc(fp)) == EOF) { printf("Read End-of-file\n"); return (char)-1; } else { return ch; } } 1-246 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also fgetc CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-247 Documented Library Functions getchar Get a character from stdin Synopsis #include int getchar(void); Description The getchar function is functionally the same as calling the getc function with stdin as its argument. A call to getchar will return the next single character from the standard input stream. The getchar function also advances the standard input's current position indicator. Error Conditions If the getchar function is unsuccessful, EOF is returned. Example #include char use_getchar(void) { char ch; if ((ch = getchar()) == EOF) { printf("getchar() failed\n"); return (char)-1; } else { return ch; } } 1-248 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also getc CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-249 Documented Library Functions getenv Get string definition from operating system Synopsis #include char *getenv (const char *name); Description The getenv function polls the operating system to see if a string is defined. There is no default operating system for the SHARC processors, so getenv always returns NULL. Error Conditions None. Example #include char *ptr; ptr = getenv ("ADI_DSP"); /* ptr = NULL */ See Also system 1-250 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library gets Get a string from a stream Synopsis #include char *gets(char *s); Description The gets function reads characters from the standard input stream into the array pointed to by s. The read terminates when a NEWLINE character is read, with the NEWLINE character being replaced by a null character in the array pointed to by s. The read will also halt if EOF is encountered. The array pointed to by s must be of equal or greater length of the input line being read. If this is not the case, the behavior is undefined. If EOF is encountered without any characters being read, then a NULL pointer is returned. Error Conditions If the gets function is not successful and a read error occurs, then a NULL pointer is returned. Example #include void fill_buffer(char *buffer) { if (gets(buffer) == NULL) printf("gets failed\n"); else printf("gets read %s\n", buffer); } CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-251 Documented Library Functions See Also fgetc, fgets, fread, fscanf 1-252 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library gmtime Convert calendar time into broken-down time as UTC Synopsis #include struct tm *gmtime(const time_t *t); Description The gmtime function converts a pointer to a calendar time into a broken-down time in terms of Coordinated Universal Time (UTC). A broken-down time is a structured variable, which is described in time.h. The broken-down time is returned by gmtime as a pointer to static memory, which may be overwritten by a subsequent call to either gmtime, or to localtime. Error Conditions None. Example #include #include time_t cal_time; struct tm *tm_ptr; cal_time = time(NULL); if (cal_time != (time_t) -1) { tm_ptr = gmtime(&cal_time); printf("The year is %4d\n",1900 + (tm_ptr->tm_year)); } CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-253 Documented Library Functions See Also localtime, mktime, time 1-254 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library heap_calloc Allocate and initialize memory in a heap Synopsis #include void *heap_calloc(int heap_index, size_t nelem, size_t size); Description The heap_calloc function is an Analog Devices extension to the ANSI standard. The heap_calloc function allocates from the heap identified by heap_inan array containing nelem elements of size, and stores zeros in all the elements of the array. If successful, it returns a pointer to this array; otherwise, it returns a null pointer. You can safely convert the return value to an object pointer of any type whose size is not greater than size. The memory may be deallocated with the free or heap_free function. dex, For more information on creating multiple run-time heaps, see the section "Using Multiple Heaps" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions The heap_calloc function returns the null pointer if unable to allocate the requested memory. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-255 Documented Library Functions Example #include #include #pragma section("seg_hp2") static char extra_heap[256]; int main() { char *buf; int index, uid = 999; /* arbitrary userid for heap */ /* Install extra_heap[] as a heap */ index = heap_install(extra_heap, sizeof(extra_heap), uid); if (index < 0) { printf("installation failed\n"); return 1; } /* Allocate memory for 128 characters from extra_heap[] */ buf = (char *)heap_calloc(index,128,sizeof(char)); if (buf != 0) { printf("Allocated space starting at %p\n", buf); free(buf); /* free can be used to release the memory */ } else { printf("Unable to allocate from extra_heap[]\n"); } return 0; } See Also calloc, free, heap_free, heap_malloc, heap_realloc, malloc, realloc, heap_space_unused 1-256 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library heap_free Return memory to a heap Synopsis #include void heap_free(int heap_index, void *ptr); Description The heap_free function is an Analog Devices extension to the ANSI standard. The heap_free function deallocates the object whose address is ptr, provided that ptr is not a null pointer. If the object was not allocated by one of the heap allocation routines, or if the object has been previously freed, then the behavior of the function is undefined. If ptr is a null pointer, then the heap_free function will just return. The function does not use the heap_index argument; instead it identifies the heap from which the object was allocated and returns the memory to this heap. For more information on creating multiple run-time heaps, see the section "Using Multiple Heaps" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions None. Example #include #include #pragma section("seg_hp2") static char extra_heap[256]; CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-257 Documented Library Functions int main() { char *buf; int index, uid = 999; /* arbitrary userid for heap */ /* Install extra_heap[] as a heap */ index = heap_install(extra_heap, sizeof(extra_heap), uid); if (index < 0) { printf("installation failed\n"); return 1; } /* Allocate memory for 128 characters from extra_heap[] */ buf = (char *)heap_calloc(index,128,sizeof(char)); if (buf != 0) { printf("Allocated space starting at %p\n", buf); heap_free(index, buf); } else { printf("Unable to allocate from extra_heap[]\n"); } return 0; } See Also calloc, free, heap_calloc, heap_malloc, heap_realloc, malloc, realloc, heap_space_unused 1-258 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library heap_init Re-initialize a heap Synopsis #include int heap_init(int heap_index); Description The heap_init function is an Analog Devices extension to the ANSI standard. The heap_init function re-initializes a heap, discarding all allocations within the heap. Because the function discards any allocations within the heap, it must not be used if there are any allocations on the heap that are still active and may be used in the future. The function returns a zero if it succeeds in re-initializing the heap specified. run-time libraries use the default heap for data storage, The . Therefore, potentially before the application has reached main re-initializing the default heap may result in erroneous or unexpected behavior. Error Conditions The heap_init function returns a non-zero result if it failed to re-initialize the heap. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-259 Documented Library Functions Example #include #include int heap_index = heap_lookup(USERID_HEAP); if (heap_init(heap_index)!=0) { printf("Heap re-initialization failed\n"); } See Also calloc, free,heap_calloc, heap_free, heap_space_unused, heap_install, heap_lookup, heap_malloc, heap_realloc, malloc, realloc, space_unused 1-260 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library heap_install Sets up a heap at runtime Synopsis #include int heap_install(void *base, size_t length, int userid); Description The heap_install function is an Analog Devices extension to the ANSI standard. The heap_install function sets up a memory heap (base) with a size specified by length at runtime. The dynamic heap is identified by the userid. Not all length words are available for user allocations. Some space is reserved for administration. On successful initialization, heap_install() returns the heap index allocated for the newly installed heap. If the operation is unsuccessful, then heap_install() returns -1. Once the dynamic heap is initialized, heap space can be claimed using the heap_malloc routine and associated heap management routines. Error Conditions The heap_install function returns -1 if initialization was unsuccessful. Potential reasons include: there is not enough space available in the __heaps table; a heap with the specified userid already exists; the space is not large enough for the internal heap structures. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-261 Documented Library Functions Example #include #define EXTRAID 666 #define EXTRASZ 256 /* LDF must map this section to appropriate memory */ #pragma section("runtime_heap") static char extra_heap[EXTRASZ]; int main() { int i; int index; int *x = NULL; index = heap_install(extra_heap, EXTRASZ, EXTRAID); if (index != -1) x = heap_malloc(index, 90*sizeof(int)); if (x) { for (i = 0; i < 90; i++) x[i] = i; } return 0; } See Also heap_malloc 1-262 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library heap_lookup Convert a userid to a heap index Synopsis #include int heap_lookup(int userid); Description The heap_lookup function is an Analog Devices extension to the ANSI standard. The heap_lookup function converts a userid to a heap index. All heaps have a userid and a heap index associated with them. Both the userid and the heap index are set on heap creation. The default heap has userid 0 and heap index 0. The heap index is required for the functions heap_calloc, heap_malloc, heap_realloc, heap_init, and heap_space_unused. For more information on creating multiple run-time heaps, see the section "Using Multiple Heaps" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions The heap_lookup function returns -1 if there is no heap with the specified userid. Example #include #include int heap_userid = 1; int heap_id; CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-263 Documented Library Functions if ( (heap_id = heap_lookup(heap_userid)) == -1) { printf("Lookup failed; will use the default heap\n"); heap_id = 0; } char *ptr = heap_malloc(heap_id, 1024); if (ptr == NULL) { printf("heap_malloc failed to allocate memory\n"); } See Also calloc, free,heap_calloc, heap_free, heap_init, heap_install, heap_space_unused, heap_malloc, heap_realloc, malloc, realloc, space_unused 1-264 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library heap_malloc Allocate memory from a heap Synopsis #include void *heap_malloc(int heap_index, size_t size); Description The heap_malloc function is an Analog Devices extension to the ANSI standard. The heap_malloc function allocates an object of size from the heap identified by heap_index. It returns the address of the object if successful; otherwise, it returns a null pointer. You can safely convert the return value to an object pointer of any type whose size is not greater than size. The block of memory is uninitialized. The memory may be deallocated with the free or heap_free function. For more information on multiple run-time heaps, see the section "Using Multiple Heaps" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions The heap_malloc function returns the null pointer if unable to allocate the requested memory. Example #include #include #pragma section("seg_hp2") CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-265 Documented Library Functions static char extra_heap[256]; int main() { char *buf; int index, uid = 999; /* arbitrary userid for heap */ /* Install extra_heap[] as a heap */ index = heap_install(extra_heap, sizeof(extra_heap), uid); if (index < 0) { printf("installation failed\n"); return 1; } /* Allocate memory for 128 characters from extra_heap[] */ buf = (char *)heap_malloc(index,128); if (buf != 0) { printf("Allocated space starting at %p\n", buf); heap_free(index, buf); } else { printf("Unable to allocate from extra_heap[]\n"); } return 0; } See Also calloc, free, heap_calloc, heap_free, heap_realloc, malloc, realloc, heap_space_unused 1-266 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library heap_realloc Change memory allocation from a heap Synopsis #include void *heap_realloc(int heap_index, void *ptr, size_t size); Description The heap_realloc function is an Analog Devices extension to the ANSI standard. The heap_realloc function changes the size of a previously allocated block of memory. The new size of the object is specified by the argument size. The modified object will contain the values of the old object up to minimum(original size, new size), while for (new size > old size) any data beyond the original size will be indeterminate. If the function successfully re-allocated the object, then it will return a pointer to the updated object. You can safely convert the return value to an object pointer of any type whose size is not greater than size in length. The behavior of the function is undefined if the object has already been freed. If ptr is a null pointer, then heap_realloc behaves the same as heap_malloc and the block of memory returned will be uninitialized. If ptr is not a null pointer, and if size is zero, then heap_realloc behaves the same as heap_free. The argument heap_index is only used if ptr is a null pointer. The memory reallocated may be deallocated with the free or heap_free function. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-267 Documented Library Functions For more information on multiple run-time heaps, see the section "Using Multiple Heaps" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors. Error Conditions The heap_realloc function returns the null pointer if unable to allocate the requested memory; the original memory associated with ptr will be unchanged and will still be available. Example #include #include #pragma section("seg_hp2") static char extra_heap[256]; int main() { char *buf, *upd; int index, uid = 999; /* arbitrary userid for heap */ /* Install extra_heap[] as a heap */ index = heap_install(extra_heap, sizeof(extra_heap), uid); if (index < 0) { printf("installation failed\n"); return 1; } /* Allocate memory for 128 characters from extra_heap[] */ buf = (char *)heap_malloc(index, 128); if (buf != 0) { strcpy(buf,"hello"); /* Change allocated size to 200 */ upd = (char *)heap_realloc(index, buf, 200); 1-268 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library if (upd != 0) { printf("reallocated string for %s\n", upd); heap_free(index, upd); /* Return to extra_heap[] */ } else { free(buf); /* free can be used to release buf */ } } else { printf("Unable to allocate from extra_heap[]\n"); } return 0; } See Also calloc, free, heap_calloc, heap_free, heap_malloc, malloc, realloc, heap_space_unused CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-269 Documented Library Functions heap_space_unused Space unused in specific heap Synopsis #include int heap_space_unused(int heap_index); Description The heap_space_unused function is an Analog Devices extension to the ANSI standard. The heap_space_unused function returns the total amount of free space for the heap with index heap_index. Note that calling heap_malloc(heap_index,heap_space_unused(heap_index)) does not allocate space because each allocated block uses more memory internally than the requested space. Note also that the free space in the heap may be fragmented, and thus may not be available in one contiguous block. Error Conditions If a heap with heap index heap_index does not exist, this function returns -1. Example #include int free_space; /* Get amount of free space in heap 1 */ free_space = heap_space_unused(1); 1-270 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also calloc, free,heap_calloc, heap_free, heap_init, heap_install, heap_lookup, heap_malloc, heap_realloc, malloc, realloc, space_unused CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-271 Documented Library Functions heap_switch Change the default heap at runtime Synopsis #include int heap_switch (int heap_index); Description The heap_switch function changes the default heap (as used by heap allocation functions malloc, calloc, realloc and free). The function returns the heapid of the previous default heap. The function does not check the validity of the heap index. If the heap index is invalid, then subsequent operations on the default heap (using the functions malloc, calloc, realloc and space_unused, or using the C++ new operator) will return an error. For more information on multiple run-time heaps, see the section "Using Multiple Heaps" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors. heap_switch function is not available in multithreaded The environments. Error Conditions None. Example #include #include #define HEAP1_USERID 1-272 1 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library #define HEAP1_SIZE 1024 int heap1[HEAP1_SIZE]; int heap1_id; char *pbuf; /* Initialize */ heap1_id = heap_install (heap1, sizeof(heap1), HEAP1_USERID); /* Make heap1 the default heap */ heap_switch (heap1_id); /* Allocate a buffer from heap1 */ pbuf = malloc (32); if (pbuf == NULL) { printf ("Unable to allocate buffer\n"); exit (EXIT_FAILURE); } else { printf("Allocated buffer from heap1 at %p\n", pbuf); } See Also calloc, free, malloc, realloc CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-273 Documented Library Functions idivfx Division of fixed-point by fixed-point to give integer result Synopsis #include int idivi(fract numer, fract denom); long int idivlr(long fract numer, long fract denom); unsigned int idivur(unsigned fract numer, unsigned fract denom); unsigned long int idivulr(unsigned long fract numer, unsigned long fract denom); Description Given a fixed-point numerator and denominator, the idivfx family of functions computes the quotient and returns the closest integer value to the result. Error Conditions The idivfx function has undefined behavior if the denominator is zero. Example #include unsigned long int ulquo; ulquo = idivulr(0.5ulr, 0.125ulr); /* ulquo == 4 */ See Also div, divifx, fxdivi, ldiv, lldiv 1-274 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library instrprof_request_flush Flush the instrumented profiling data to the host Synopsis #include void instrprof_request_flush(void); Description The instrprof_request_flush function attempts to flush any buffered instrumented profiling data to the host computer. The flush occurs immediately if file I/O operations are allowed. (File I/O operations cannot be executed from interrupt handlers or from unscheduled regions in a multi-threaded application.) If the flush cannot occur immediately, it occurs the next time a profiled function is called, or returned from when file I/O operations are allowed. Do not include the header file or reference the func tion in an application that is not built instrprof.h instrprof_request_flush with instrumented profiling enabled. more information, see the section "-p" in the C/C++ Compiler For Manual for SHARC Processors. You can guard such code using the preprocessor macro _INSTRUMENTED_PROFILING. Note that the compiler only defines this macro when instrumented profiling is enabled. Flushing data to the host is a cycle-intensive operation. Consider carefully when and where to call this function within your application. For more information, see "Profiling With Instrumented Code" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-275 Documented Library Functions Error Conditions None. Example #if defined (_INSTRUMENTED_PROFILING) #include #endif extern void do_something(void); int main(void) { do_something(); #if defined(_INSTRUMENTED_PROFILING) instrprof_request_flush(); #endif } 1-276 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library ioctl Apply a control operation to a file descriptor Synopsis #include int ioctl(int fildes, int cmd, ...); Description The ioctl function applies command cmd to file descriptor fildes, along with any specified arguments for cmd. The file descriptor must be a value returned by invoking the fileno function upon some open stream fp. The ioctl function is delegated to the device driver upon which stream fp was opened. The command cmd, and any provided arguments, are specific to the device driver; each device driver may interpret commands and arguments differently. Error Conditions The ioctl function returns -1 if the operation is not recognized by the underlying device driver. Other return values are specific to the device driver's interpretation of the command. Example #include int apply_control_cmd(FILE *fp, int cmd, int val) { int fildes = fileno(fp); return ioctl(fildes, cmd, val); } See Also fopen, fileno CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-277 Documented Library Functions isalnum Detect alphanumeric character Synopsis #include int isalnum (int c); Description The isalnum function determines if the argument is an alphanumeric character (A-Z, a-z, or 0-9). If the argument is not alphanumeric, the isalnum function returns a zero. If the argument is alphanumeric, isalnum returns a non-zero value. Error Conditions None. Example #include int ch; for (ch = 0; ch <= 0x7f; ch++) { printf ("%#04x", ch); printf ("%3s", isalnum (ch) ? "alphanumeric" : ""); putchar ('\n'); } See Also isalpha, isdigit 1-278 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library isalpha Detect alphabetic character Synopsis #include int isalpha (int c); Description The isalpha function determines if the argument is an alphabetic character (A-Z or a-z). If the argument is not alphabetic, isalpha returns a zero. If the argument is alphabetic, isalpha returns a non-zero value. Error Conditions None. Example #include int ch; for (ch = 0; ch <= 0x7f; ch++) { printf ("%#04x", ch); printf ("%2s", isalpha (ch) ? "alphabetic" : ""); putchar ('\n'); } See Also isalnum, isdigit CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-279 Documented Library Functions iscntrl Detect control character Synopsis #include int iscntrl (int c); Description The iscntrl function determines if the argument is a control character (0x00-0x1F or 0x7F). If the argument is not a control character, iscntrl returns a zero. If the argument is a control character, iscntrl returns a non-zero value. Error Conditions None. Example #include int ch; for (ch = 0; ch <= 0x7f; ch++) { printf ("%#04x", ch); printf ("%2s", iscntrl (ch) ? "control" : ""); putchar ('\n'); } See Also isalnum, isgraph 1-280 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library isdigit Detect decimal digit Synopsis #include int isdigit (int c); Description The isdigit function determines if the argument c is a decimal digit (0-9). If the argument is not a digit, isdigit returns a zero. If the argument is a digit, isdigit returns a non-zero value. Error Conditions None. Example #include int ch; for (ch = 0; ch <= 0x7f; ch++) { printf ("%#04x", ch); printf ("%2s", isdigit (ch) ? "digit" : ""); putchar ('\n'); } See Also isalnum, isalpha, isdigit CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-281 Documented Library Functions isgraph Detect printable character, not including white space Synopsis #include int isgraph (int c); Description The isgraph function determines if the argument is a printable character, not including a white space (0x21-0x7e). If the argument is not a printable character, isgraph returns a zero. If the argument is a printable character, isgraph returns a non-zero value. Error Conditions None. Example #include int ch; for (ch = 0; ch <= 0x7f; ch++) { printf ("%#04x", ch); printf ("%2s", isgraph (ch) ? "graph" : ""); putchar ('\n'); } See Also isalnum, iscntrl, isprint 1-282 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library isinf Test for infinity Synopsis #include int isinff(float x); int isinf(double x); int isinfd(long double x); Description The isinf functions are an Analog Devices extension to the ANSI standard. The isinf functions return a zero if the argument x is not set to the IEEE constant for +Infinity or -Infinity; otherwise, the functions return a non-zero value. Error Conditions None. Example #include static long val[5] = { 0x7F7FFFFF, /* FLT_MAX */ 0x7F800000, /* Inf */ 0xFF800000, /* -Inf */ 0x7F808080, /* NaN */ 0xFF808080, /* NaN */ }; float *pval = (float *)(&val); int m; CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-283 Documented Library Functions m = isinf (pval[0]); /* m set to zero m = isinf (pval[1]); /* m set to non-zero */ */ m = isinf (pval[2]); /* m set to non-zero */ m = isinf (pval[3]); /* m set to zero */ m = isinf (pval[4]); /* m set to zero */ See Also isnan 1-284 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library islower Detect lowercase character Synopsis #include int islower (int c); Description The islower function determines if the argument is a lowercase character (a-z). If the argument is not lowercase, islower returns a zero. If the argument is lowercase, islower returns a non-zero value. Error Conditions None. Example #include int ch; for (ch = 0; ch <= 0x7f; ch++) { printf ("%#04x", ch); printf ("%2s", islower (ch) ? "lowercase" : ""); putchar ('\n'); } See Also isalpha, isupper CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-285 Documented Library Functions isnan Test for Not a Number (NaN) Synopsis #include int isnanf(float x); int isnan(double x); int isnand(long double x); Description The isnan functions are an Analog Devices extension to the ANSI standard. The isnan functions return a zero if the argument x is not set to an IEEE NaN (Not a Number); otherwise, the functions return a non-zero value. Error Conditions None. Example #include static long val[5] = { 0x7F7FFFFF, /* FLT_MAX */ 0x7F800000, /* Inf */ 0xFF800000, /* -Inf */ 0x7F808080, /* NaN */ 0xFF808080, /* NaN */ }; float *pval = (float *)(&val); int m; 1-286 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library m = isnanf (pval[0]); /* m set to zero */ m = isnanf (pval[1]); /* m set to zero */ m = isnanf (pval[2]); /* m set to zero */ m = isnanf (pval[3]); /* m set to non-zero */ m = isnanf (pval[4]); /* m set to non-zero */ See Also isinf CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-287 Documented Library Functions isprint Detect printable character Synopsis #include int isprint (int c); Description The isprint function determines if the argument is a printable character (0x20-0x7E). If the argument is not a printable character, isprint returns a zero. If the argument is a printable character, isprint returns a non-zero value. Error Conditions None. Example #include int ch; for (ch = 0; ch <= 0x7f; ch++) { printf ("%#04x", ch); printf ("%3s", isprint (ch) ? "printable" : ""); putchar ('\n'); } See Also isgraph, isspace 1-288 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library ispunct Detect punctuation character Synopsis #include int ispunct (int c); Description The ispunct function determines if the argument is a punctuation character. If the argument is not a punctuation character, ispunct returns a zero. If the argument is a punctuation character, ispunct returns a non-zero value. Error Conditions None. Example #include int ch; for (ch = 0; ch <= 0x7f; ch++) { printf ("%#04x", ch); printf ("%3s", ispunct (ch) ? "punctuation" : ""); putchar ('\n'); } See Also isalnum CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-289 Documented Library Functions isspace Detect whitespace character Synopsis #include int isspace (int c); Description The isspace function determines if the argument is a blank whitespace character (0x09-0x0D or 0x20). This includes space ( ), form feed (\f), new line (\n), carriage return (\r), horizontal tab (\t) and vertical tab (\v). If the argument is not a blank whitespace character, isspace returns a zero. If the argument is a blank whitespace character, isspace returns a non-zero value. Error Conditions None. Example #include int ch; for (ch = 0; ch <= 0x7f; ch++) { printf ("%#04x", ch); printf ("%2s", isspace (ch) ? "space" : ""); putchar ('\n'); } 1-290 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also iscntrl, isgraph CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-291 Documented Library Functions isupper Detect uppercase character Synopsis #include int isupper (int c); Description The isupper function determines if the argument is an uppercase character (A-Z). If the argument is not an uppercase character, isupper returns a zero. If the argument is an uppercase character, isupper returns a non-zero value. Error Conditions None. Example #include int ch; for (ch = 0; ch <= 0x7f; ch++) { printf ("%#04x", ch); printf ("%2s", isupper (ch) ? "uppercase" : ""); putchar ('\n'); } See Also isalpha, islower 1-292 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library isxdigit Detect hexadecimal digit Synopsis #include int isxdigit (int c); Description The isxdigit function determines if the argument is a hexadecimal digit character (A-F, a-f, or 0-9). If the argument is not a hexadecimal digit, isxdigit returns a zero. If the argument is a hexadecimal digit, isxdigit returns a non-zero value. Error Conditions None. Example #include int ch; for (ch = 0; ch <= 0x7f; ch++) { printf ("%#04x", ch); printf ("%2s", isxdigit (ch) ? "hexadecimal" : ""); putchar ('\n'); } See Also isalnum, isdigit CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-293 Documented Library Functions labs Absolute value Synopsis #include long int labs (long int j); Description The labs function returns the absolute value of its integer argument. Note that labs (LONG_MIN) == LONG_MIN. Error Conditions None. Example #include long int j; j = labs (-285128); /* j = 285128 */ See Also abs, absfx, fabs, llabs 1-294 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library lavg Mean of two values Synopsis #include long int lavg (long int value1, long int value2); Description The lavg function is an Analog Devices extension to the ANSI standard. The lavg function adds two arguments and divides the result by two. The lavg function is a built-in function which is implemented with an Rn=(Rx+Ry)/2 instruction. Error Conditions None. Example #include long int i; i = lavg (10, 8); /* returns 9 */ See Also abs, avg, llavg CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-295 Documented Library Functions lclip Clip Synopsis #include long int lclip (long int value1, long int value2); Description The lclip function is an Analog Devices extension to the ANSI standard. The lclip function returns the first argument if its absolute value is less than the absolute value of the second argument; otherwise it returns the absolute value of its second argument if the first is positive, or minus the absolute value if the first argument is negative. The lclip function is a built-in function which is implemented with an Rn = CLIP Rx BY Ry instruction. Error Conditions None. Example #include long int i; i = lclip (10, 8); /* returns 8 */ i = lclip (8, 10); /* returns 8 */ i = lclip (-10, 8); /* returns -8 */ See Also clip, fclip, llclip 1-296 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library lcount_ones Count one bits in word Synopsis #include int lcount_ones (long int value); Description The lcount_ones function is an Analog Devices extension to the ANSI standard. The lcount_ones function returns the number of one bits in its argument. Error Conditions None. Example #include long int flags1 = 4095; long int flags2 = 4096; int cnt1; int cnt2; cnt1 = lcount_ones (flags1); /* returns 12 */ cnt2 = lcount_ones (flags2); /* returns 1 */ See Also count_ones, llcount_ones CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-297 Documented Library Functions ldexp Multiply by power of 2 Synopsis #include float ldexpf (float x, int n); double ldexp (double x, int n); long double ldexpd (long double x, int n); Description The ldexp functions return the value of the floating-point argument multiplied by 2n. These functions add the value of n to the exponent of x. Error Conditions If the result overflows, the ldexp functions return HUGE_VAL with the proper sign. If the result underflows, a zero is returned. Example #include double y; float x; y = ldexp (0.5, 2); /* y = 2.0 */ x = ldexpf (1.0, 2); /* x = 4.0 */ See Also exp, pow 1-298 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library ldiv Long division Synopsis #include ldiv_t ldiv (long int numer, long int denom); Description The ldiv function divides numer by denom, and returns a structure of type ldiv_t. The type ldiv_t is defined as: typedef struct { long int quot; long int rem; } ldiv_t; where quot is the quotient of the division and rem is the remainder, such that if result is of type ldiv_t, then result.quot * denom + result.rem == numer Error Conditions If denom is zero, the behavior of the ldiv function is undefined. Example #include ldiv_t result; result = ldiv (7L, 2L); /* result.quot = 3, result.rem = 1 */ CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-299 Documented Library Functions See Also div, divifx, fmod, fxdivi, idivfx, lldiv 1-300 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library llabs Absolute value Synopsis #include long long llabs (long long j); Description The llabs function returns the absolute value of its integer argument. Note that llabs (LLONG_MIN) == LLONG_MIN. Error Conditions None. Example #include long long j; j = llabs (-27081970LL); /* j = 27081970 */ See Also abs, absfx, fabs, labs CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-301 Documented Library Functions llavg Mean of two values Synopsis #include long long llavg (long long value1, long long value2); Description The llavg function is an extension to the ISO/IEC 9899:1990 C standard and the ISO/IEC 9899:1999 C standard. The llavg function returns the average of the two arguments value1 and value2. Error Conditions None. Example #include long long i; i = llavg (10LL, 8LL); /* returns 9 */ See Also abs, avg, lavg 1-302 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library llclip Clip Synopsis #include long long llclip (long long value1, long long value2); Description The llclip function is an extension to the ISO/IEC 9899:1990 C standard and the ISO/IEC 9899:1999 C standard. The llclip function returns the first argument if its absolute value is less than the absolute value of the second argument; otherwise it returns the absolute value of its second argument if the first is positive, or minus the absolute value if the first argument is negative. Error Conditions None. Example #include long long i; i = llclip (10LL, 8LL); /* returns 8 */ i = llclip (8LL, 10LL); /* returns 8 */ i = llclip (-10LL, 8LL); /* returns -8 */ See Also clip, fclip, lclip CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-303 Documented Library Functions llcount_ones Count one bits in long long Synopsis #include int llcount_ones (long long value); Description The llcount_ones function is an extension to the ISO/IEC 9899:1990 C standard and the ISO/IEC 9899:1999 C standard. The llcount_ones function returns the number of one bits in its argument. Error Conditions None. Example #include long long flags1 = 4095LL; long long flags2 = 4096LL; int cnt1; int cnt2; cnt1 = llcount_ones (flags1); /* returns 12 */ cnt2 = llcount_ones (flags2); /* returns 1 */ See Also count_ones, lcount_ones 1-304 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library lldiv Long long division Synopsis #include lldiv_t lldiv (long long numer, long long denom); Description The lldiv function divides numer by denom, and returns a structure of type lldiv_t. The type lldiv_t is defined as: typedef struct { long long quot; long long rem; } lldiv_t; where quot is the quotient of the division and rem is the remainder, such that if result is of type lldiv_t, then result.quot * denom + result.rem == numer Error Conditions If denom is zero, the behavior of the lldiv function is undefined. Example #include lldiv_t result; result = lldiv (7LL, 2LL); /* result.quot = 3, result.rem = 1 */ CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-305 Documented Library Functions See Also div, divifx, fmod, fxdivi, idivfx, ldiv 1-306 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library llmax Long long maximum Synopsis #include long long llmax (long long value1, long long value2); Description The llmax function is an extension to the ISO/IEC 9899:1990 C standard and the ISO/IEC 9899:1999 C standard. The llmax function returns the larger of its two arguments. Error Conditions None. Example #include long long i; i = llmax (10LL, 8LL); /* returns 10 */ See Also fmax, fmin, llmin, lmax, lmin, max, min CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-307 Documented Library Functions llmin Long long minimum Synopsis #include long long llmin (long long value1, long long value2); Description The llmin function is an extension to the ISO/IEC 9899:1990 C standard and the ISO/IEC 9899:1999 C standard. The llmin function returns the smaller of its two arguments. Error Conditions None. Example #include long long i; i = llmin (10LL, 8LL); /* returns 8 */ See Also fmax, fmin, llmax, lmax, lmin, max, min 1-308 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library lmax Long int maximum Synopsis #include long int lmax (long int value1, long int value2); Description The lmax function is an extension to the ISO/IEC 9899:1990 C standard and the ISO/IEC 9899:1999 C standard. The lmax function returns the larger of its two arguments. The lmax function is a built-in function which is implemented with an Rn = MAX(Rx,Ry) instruction. Error Conditions None. Example #include long int i; i = lmax (10L, 8L); /* returns 10 */ See Also fmax, fmin, llmax, llmin, lmin, max, min CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-309 Documented Library Functions lmin Long minimum Synopsis #include long int lmin (long int value1, long int value2); Description The lmin function is an extension to the ISO/IEC 9899:1990 C standard and the ISO/IEC 9899:1999 C standard. The lmin function returns the smaller of its two arguments. The lmin function is a built-in function which is implemented with an Rn = MIN(Rx,Ry) instruction. Error Conditions None. Example #include long int i; i = lmin (10L, 8L); /* returns 8 */ See Also fmax, fmin, llmin, llmax, lmax, max, min 1-310 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library localeconv Get pointer for formatting to current locale Synopsis #include struct lconv *localeconv (void); Description The localeconv function returns a pointer to an object of type struct lconv. This pointer is used to set the components of the object with values used in formatting numeric quantities in the current locale. With the exception of decimal_point, those members of the structure with type char* may use " " to indicate that a value is not available. Expected values are strings. Those members with type char may use CHAR_MAX to indicate that a value is not available. Expected values are non-negative numbers. The program may not alter the structure pointed to by the return value but subsequent calls to localeconv may do so. Also, calls to setlocale with the category arguments of LC_ALL, LC_MONETARY and LC_NUMERIC may overwrite the structure. Table 1-40. Members of the lconv Struct Member Description char *currency_symbol Currency symbol applicable to the locale char *decimal_point Used to format nonmonetary quantities char *grouping Used to indicate the number of digits in each nonmonetary grouping char *int_curr_symbol Used as international currency symbol (ISO 4217:1987) for that particular locale plus the symbol used to separate the currency symbol from the monetary quantity CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-311 Documented Library Functions Table 1-40. Members of the lconv Struct (Cont'd) Member Description char *mon_decimal_point Used for decimal point format monetary quantities char *mon_grouping Used to indicate the number of digits in each monetary grouping char *mon_thousands_sep Used to group monetary quantities prior to the decimal point char *negative_sign Used to indicate a negative monetary quantity char *positive_sign Used to indicate a positive monetary quantity char *thousands_sep Used to group nonmonetary quantities prior to the decimal point char frac_digits Number of digits displayed after the decimal point in monetary quantities in other than international format char int_frac_digits Number of digits displayed after the decimal point in international monetary quantities char p_cs_precedes If set to 1, the currency_symbol precedes the positive monetary quantity. If set to 0, the currency_symbol succeeds the positive monetary quantity. char n_cs_precedes If set to 1, the currency_symbol precedes the negative monetary quantity. If set to 0, the currency_symbol succeeds the negative monetary quantity. char n_sign_posn Indicates the positioning of negative_sign for monetary quantities. char n_sep_by_space If set to 1, the currency_symbol is separated from the negative monetary quantity. If set to 0, the currency_symbol is not separated from the negative monetary quantity. char p_sep_by_space If set to 1, the currency_symbol is separated from the positive monetary quantity. If set to 0, the currency_symbol is not separated from the positive monetary quantity. For grouping and non_grouping, an element of CHAR_MAX indicates that no further grouping will be performed, a 0 indicates that the previous 1-312 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library element should be used to group the remaining digits, and any other integer value is used as the number of digits in the current grouping. The definitions of the values for p_sign_posn and n_sign_posn are: * parentheses surround currency_symbol and quantity * sign string precedes currency_symbol and quantity * sign string succeeds currency_symbol and quantity * sign string immediately precedes currency_symbol * sign string immediately succeeds currency_symbol Error Conditions None. Example #include struct lconv *c_locale; c_locale = localeconv (); /* Only the C locale is */ /* currently supported */ See Also setlocale CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-313 Documented Library Functions localtime Convert calendar time into broken-down time Synopsis #include struct tm *localtime(const time_t *t); Description The localtime function converts a pointer to a calendar time into a broken-down time that corresponds to current time zone. A broken-down time is a structured variable, which is described in time.h. This implementation of the header file does not support the Daylight Saving flag nor does it support time zones and, thus, localtime is equivalent to the gmtime function. The broken-down time is returned by localtime as a pointer to static memory, which may be overwritten by a subsequent call to either localtime, or to gmtime. Error Conditions None. Example #include #include time_t cal_time; struct tm *tm_ptr; 1-314 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library cal_time = time(NULL); if (cal_time != (time_t) -1) { tm_ptr = localtime(&cal_time); printf("The year is %4d\n",1900 + (tm_ptr->tm_year)); } See Also asctime, gmtime, mktime, time CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-315 Documented Library Functions log Natural logarithm Synopsis #include float logf (float x); double log (double x); long double logd (long double x); Description The natural logarithm functions compute the natural (base e) logarithm of their argument. Error Conditions The natural logarithm functions return zero and set errno to EDOM if the input value is zero or negative. Example #include double y; float x; y = log (1.0); /* y = 0.0 */ x = logf (2.71828); /* x = 1.0 */ See Also alog, exp, log10 1-316 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library log10 Base 10 logarithm Synopsis #include float log10f (float x); double log10 (double x); long double log10d (long double x); Description The log10 functions produce the base 10 logarithm of their argument. Error Conditions The log10 functions indicate a domain error (set errno to EDOM) and return zero if the input is zero or negative. Example #include double y; float x; y = log10 (100.0); /* y = 2.0 */ x = log10f (10.0); /* x = 1.0 */ See Also alog, log, pow CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-317 Documented Library Functions longjmp Second return from setjmp Synopsis #include void longjmp (jmp_buf env, int return_val); Description The longjmp function causes the program to execute a second return from the place where setjmp (env) was called (with the same jmp_buf argument). The longjmp function takes as its arguments a jump buffer that contains the context at the time of the original call to setjmp. It also takes an integer, return_val, which setjmp returns if return_val is non-zero. Otherwise, setjmp returns a 1. If env was not initialized through a previous call to setjmp or the function that called setjmp has since returned, the behavior is undefined. use of and (or similar functions which do not The follow conventional C/C++ flow control) may produce unexpected setjmp longjmp results when the application is compiled with optimizations enabled under certain circumstances. Functions that call setjmp or longjmp are optimized by the compiler with the assumption that all variables referenced may be modified by any functions that are called. This assumption ensures that it is safe to use setjmp and longjmp with optimizations enabled, though it does mean that it is dangerous to conceal from the optimizer that a call to setjmp or longjmp is being made, for example by calling through a function pointer. 1-318 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Error Conditions None. Example #include #include #include #include jmp_buf env; int res; void func (void); main() { if ((res = setjmp(env)) != 0) { printf ("Problem %d reported by func ()\n", res); exit (EXIT_FAILURE); } func(); } void func (void) { if (errno != 0) { longjmp (env, errno); } } See Also setjmp CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-319 Documented Library Functions malloc Allocate memory Synopsis #include void *malloc (size_t size); Description The malloc function returns a pointer to a block of memory of length size. The block of memory is uninitialized. The object is allocated from the current heap, which is the default heap unless heap_switch has been called to change the current heap to an alternate heap. Error Conditions The malloc function returns a null pointer if it is unable to allocate the requested memory. Example #include int *ptr; size_t sz = 10 * sizeof(int); ptr = (int *)malloc (sz); /* ptr points to an */ /* array of length 10 */ See Also calloc, free, heap_calloc, heap_free, heap_malloc, heap_realloc, realloc 1-320 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library max Maximum Synopsis #include int max (int value1, int value2); Description The max function is an extension to the ISO/IEC 9899:1990 C standard and the ISO/IEC 9899:1999 C standard. The max function returns the larger of its two arguments. The max function is a built-in function which is implemented with an Rn = MAX(Rx,Ry) instruction. Error Conditions None. Example #include int i; i = max (10, 8); /* returns 10 */ See Also fmax, fmin, llmax, llmin, lmax, lmin, min CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-321 Documented Library Functions memchr Find first occurrence of character Synopsis #include void *memchr (const void *s1, int c, size_t n); Description The memchr function compares the range of memory pointed to by s1 with the input character c and returns a pointer to the first occurrence of c. A null pointer is returned if c does not occur in the first n characters. Error Conditions None. Example #include char *ptr; ptr = memchr ("TESTING", 'E', 7); /* ptr points to the E in TESTING */ See Also strchr, strrchr 1-322 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library memcmp Compare objects Synopsis #include int memcmp (const void *s1, const void *s2, size_t n); Description The memcmp function compares the first n characters of the objects pointed to by s1 and s2. It returns a positive value if the s1 object is lexically greater than the s2 object, a negative value if the s2 object is lexically greater than the s1 object, and a zero if the objects are the same. Error Conditions None. Example #include char *string1 = "ABC"; char *string2 = "BCD"; int result; result = memcmp (string1, string2, 3); /* result < 0 */ See Also strcmp, strcoll, strcmp CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-323 Documented Library Functions memcpy Copy characters from one object to another Synopsis #include void *memcpy (void *s1, const void *s2, size_t n); Description The memcpy function copies n characters from the object pointed to by s2 into the object pointed to by s1. The behavior of memcpy is undefined if the two objects overlap. For more information, see memmove. The memcpy function returns the address of s1. Error Conditions None. Example #include char *a = "SRC"; char *b = "DEST"; memcpy (b, a, 3); /* b = "SRCT" */ See Also memmove, strcpy, strncpy 1-324 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library memmove Copy characters between overlapping objects Synopsis #include void *memmove (void *s1, const void *s2, size_t n); Description The memmove function copies n characters from the object pointed to by s2 into the object pointed to by s1. The entire object is copied correctly even if the objects overlap. The memmove function returns a pointer to s1. Error Conditions None. Example #include char *ptr, *str = "ABCDE"; ptr = str + 2; memmove (ptr, str, 3); /* ptr = "ABC", str = "ABABC" */ See Also memcpy, strcpy, strncpy CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-325 Documented Library Functions memset Set range of memory to a character Synopsis #include void *memset (void *s1, int c, size_t n); Description The memset function sets a range of memory to the input character c. The first n characters of s1 are set to c. The memset function returns a pointer to s1. Error Conditions None. Example #include char string1[50]; memset (string1, '\0', 50); /* set string1 to 0 */ See Also memcpy 1-326 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library min Minimum Synopsis #include int min (int value1, int value2); Description The min function is an extension to the ISO/IEC 9899:1990 C standard and the ISO/IEC 9899:1999 C standard. The min function returns the smaller of its two arguments. The min function is a built-in function which is implemented with an Rn=MIN(Rx,Ry) instruction. Error Conditions None. Example #include int i; i = min (10, 8); /* returns 8 */ See Also fmin, llmax, llmin, lmax, lmin, max CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-327 Documented Library Functions mktime Convert broken-down time into a calendar time Synopsis #include time_t mktime(struct tm *tm_ptr); Description The mktime function converts a pointer to a broken-down time, which represents a local date and time, into a calendar time. However, this implementation of time.h does not support either daylight saving or time zones and hence this function will interpret the argument as Coordinated Universal Time (UTC). A broken-down time is a structured variable which is defined in the time.h header file as: struct tm { int tm_sec; /* seconds after the minute [0,61] */ int tm_min; /* minutes after the hour [0,59] */ int tm_hour; /* hours after midnight [0,23] */ int tm_mday; /* day of the month [1,31] */ int tm_mon; /* months since January [0,11] */ int tm_year; /* years since 1900 */ int tm_wday; /* days since Sunday [0, 6] */ int tm_yday; /* days since January 1st [0,365] */ int tm_isdst; /* Daylight Saving flag */ }; The various components of the broken-down time are not restricted to the ranges indicated above. The mktime function calculates the calendar time from the specified values of the components (ignoring the initial values of tm_wday and tm_yday), and then "normalizes" the broken-down time forcing each component into its defined range. 1-328 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library If the component tm_isdst is zero, then the mktime function assumes that daylight saving is not in effect for the specified time. If the component is set to a positive value, then the function assumes that daylight saving is in effect for the specified time and will make the appropriate adjustment to the broken-down time. If the component is negative, the mktime function should attempt to determine whether daylight saving is in effect for the specified time but because neither time zones nor daylight saving are supported, the effect will be as if tm_isdst were set to zero. Error Conditions The mktime function returns the value ((time_t) cannot be represented. -1) if the calendar time Example #include #include static const char *wday[] = {"Sun","Mon","Tue","Wed", "Thu","Fri","Sat","???"}; struct tm tm_time = {0,0,0,0,0,0,0,0,0}; tm_time.tm_year = 2000 - 1900; tm_time.tm_mday = 1; if (mktime(&tm_time) == -1) tm_time.tm_wday = 7; printf("%4d started on a %s\n", 1900 + tm_time.tm_year, wday[tm_time.tm_wday]); CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-329 Documented Library Functions See Also gmtime, localtime, time 1-330 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library modf Separate integral and fractional parts Synopsis #include float modff (float x, float *intptr); double modf (double x, double *intptr); long double modfd (long double x, long double *intptr); Description The modf functions separate the first argument into integral and fractional portions. The fractional portion is returned and the integral portion is stored in the object pointed to by intptr. The integral and fractional portions have the same sign as the input. Error Conditions None. Example #include double y, n; float m, p; y = modf (-12.345, &n); /* y = -0.345, n = -12.0 */ m = modff (11.75, &p); /* m = 0.75, p = 11.0 */ See Also frexp CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-331 Documented Library Functions mulifx Multiplication of integer by fixed-point to give integer result Synopsis #include int mulir(int a, fract b); long int mulilr(long int a, long fract b); unsigned int muliur(unsigned int a, unsigned fract b); unsigned long int muliulr(unsigned long int a, unsigned long fract b); Description Given an integer and a fixed-point value, the mulifx family of functions computes the product and returns the closest integer value to the result. Error Conditions None. Example #include unsigned long int ulprod; ulprod = muliulr(128, 0.125ulr); /* ulquo == 16 */ See Also No related functions. 1-332 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library perror Print an error message on standard error stream Synopsis #include void perror(const char *s); Description The perror function is used to output an error message to the standard stream stderr. If the string s is not a null pointer and if the first character addressed by s is not a null character, then the function will output the string s followed by the character sequence ": ". The function will then print the message that is associated with the current value of errno. Note that the message "no error" is used if the value of errno is zero. Error Conditions None. Example #include #include #include float x; x = acosf (1234.5); /* domain of acosf is [-1.0,1.0] */; if (errno != 0) perror("acosf failure"); CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-333 Documented Library Functions See Also strerror 1-334 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library pgo_hw_request_flush Request a flush to the host of the data gathered through profile-guided optimization on hardware Synopsis #include void pgo_hw_request_flush(void); Description The pgo_hw_request_flush function requests that the runtime support for profile-guided optimization on hardware should write gathered data to the host computer. The flush occurs the next time the profile-guided optimization on hardware run-time support attempts to record data, as long as file I/O operations are allowed. (File I/O operations cannot be executed from interrupt handlers or when in an unscheduled region in a multi-threaded application.) the function Do not include the headerin anfileapplication ornotreference built for propgo_hw.h pgo_hw_request_flush file-guided optimization on hardware. You can guard such code using the preprocessor macro _PGO_HW; the compiler only defines this macro when profile-guided optimization for hardware is enabled. For more information, see "-pguide" and "-prof-hw" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors. Flushing data to the host is a cycle-intensive operation. Consider carefully when and where to call this function within your application. For more information, see "Profile Guided Optimization and Code Coverage" in Chapter 2 of the C/C++ Compiler Manual for SHARC Processors. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-335 Documented Library Functions Error Conditions None. Example #if defined (_PGO_HW) #include #endif extern void do_something(void); int main(void) { do_something(); #if defined(_PGO_HW) pgo_hw_request_flush(); #endif } 1-336 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library pow Raise to a power Synopsis #include float powf (float x, float y); double pow (double x, double y); long double powd (long double x, long double y); Description The power functions compute the value of the first argument raised to the power of the second argument. Error Conditions A domain error occurs if the first argument is negative and the second argument cannot be represented as an integer. If the first argument is zero, the second argument is less than or equal to zero and the result cannot be represented, zero is returned. Example #include double z; float x; z = pow (4.0, 2.0); /* z = 16.0 */ x = powf (4.0, 2.0); /* x = 16.0 */ See Also exp, ldexp CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-337 Documented Library Functions printf Print formatted output Synopsis #include int printf(const char *format, /* args*/ ...); Description The printf function places output on the standard output stream stdout in a form specified by format. The printf function is equivalent to fprintf with the stdout passed as the first argument. The argument format contains a set of conversion specifiers, directives, and ordinary characters that are used to control how the data is formatted. Refer to fprintf (on page 1-217) for a description of the valid format specifiers. The printf function returns the number of characters transmitted. Error Conditions If the printf function is unsuccessful, a negative value is returned. Example #include void printf_example(void) { int arg = 255; /* Output will be "hex:ff, octal:377, integer:255" */ printf("hex:%x, octal:%o, integer:%d\n", arg, arg, arg); } 1-338 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also fprintf CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-339 Documented Library Functions putc Put a character on a stream Synopsis #include int putc(int ch, FILE *stream); Description The putc function writes its argument to the output stream pointed to by stream, after converting ch from an int to an unsigned char. If the putc function call is successful putc returns its argument ch. Error Conditions The stream's error indicator will be set if the call is unsuccessful, and the function will return EOF. Example #include void putc_example(void) { /* write the character 'a' to stdout */ if (putc('a', stdout) == EOF) fprintf(stderr, "putc failed\n"); } See Also fputc 1-340 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library putchar Write a character to stdout Synopsis #include int putchar(int ch); Description The putchar function writes its argument to the standard output stream, after converting ch from an int to an unsigned char. A call to putchar is equivalent to calling putc(ch, stdout). If the putchar function call is successful putchar returns its argument ch. Error Conditions The stream's error indicator will be set if the call is unsuccessful, and the function will return EOF. Example #include void putchar_example(void) { /* write the character 'a' to stdout */ if (putchar('a') == EOF) fprintf(stderr, "putchar failed\n"); } See Also putc CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-341 Documented Library Functions puts Put a string to stdout Synopsis #include int puts(const char *s); Description The puts function writes the string pointed to by s, followed by a NEWLINE character, to the standard output stream stdout. The terminating null character of the string is not written to the stream. If the function call is successful then the return value is zero or greater. Error Conditions The macro EOF is returned if puts was unsuccessful, and the error indicator for stdout will be set. Example #include void puts_example(void) { /* write the string "example" to stdout */ if (puts("example") < 0) fprintf(stderr, "puts failed\n"); } See Also fputs 1-342 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library qsort Quicksort Synopsis #include void qsort (void *base, size_t nelem, size_t size, int (*compar) (const void *, const void *)); Description The qsort function sorts an array of nelem objects, pointed to by base. The size of each object is specified by size. The contents of the array are sorted into ascending order according to a comparison function pointed to by compar, which is called with two arguments that point to the objects being compared. The function shall return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second. If two elements compare as equal, their order in the sorted array is unspecified. The qsort function executes a binary-search operation on a pre-sorted array, where * base points to the start of the array. * nelem * size * is a pointer to a function that is called by qsort to compare two elements of the array. The function should return a value less than, equal to, or greater than zero, according to whether the first argument is less than, equal to, or greater than the second. is the number of elements in the array. is the size of each element of the array. compar CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-343 Documented Library Functions Error Conditions None. Example #include float a[10]; int compare_float (const void *a, const void *b) { float aval = *(float *)a; float bval = *(float *)b; if (aval < bval) return -1; else if (aval == bval) return 0; else return 1; } qsort (a, sizeof (a)/sizeof (a[0]), sizeof (a[0]), compare_float); See Also bsearch 1-344 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library raise Force a signal Synopsis #include int raise (int sig); Description The raise function invokes the function registered for signal sig by function signal, if any. The sig argument must be one of the signals listed in signal. raise function provides the functionality described in the The ISO/IEC 9899:1999 Standard, and has no impact on the processor's interrupt mechanisms. For information on handling interrupts, refer to the System Run-Time Documentation in the online help. Error Conditions The raise function returns a zero if successful or a non-zero value if sig is an unrecognized signal value. Example #include raise(SIGABRT); /* equivalent to calling abort() */ See Also signal CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-345 Documented Library Functions rand Random number generator Synopsis #include int rand (void); Description The rand function returns a pseudo-random integer value in the range [0, 231 - 1]. For this function, the measure of randomness is its periodicity, the number of values it is likely to generate before repeating a pattern. The output of the pseudo-random number generator has a period in the order of 231 - 1. Error Conditions None. Example #include int i; i = rand (); See Also srand 1-346 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library read_extmem Read external memory Synopsis #include <21261.h> #include <21262.h> #include <21266.h> #include <21362.h> #include <21363.h> #include <21364.h> #include <21365.h> #include <21366.h> void read_extmem(void *internal_address, void *external_address, size_t n); Description On ADSP-2126x and some ADSP-2136x processors, it is not possible for the core to access external memory directly. The read_extmem function copies data from external to internal memory. The read_extmem function will transfer n 32-bit words from external_address to internal_address. Error Conditions None. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-347 Documented Library Functions Example #include <21262.h> int intmem1[100]; int intmem2[100]; /* Place extmem1 in external memory, in the used-defined */ /* section "seg_extmem" */ #pragma section("seg_extmem", DMA_ONLY) int extmem1[100]; /* Place extmem2 in external memory, in the used-defined */ /* section "seg_extmem" */ #pragma section("seg_extmem", DMA_ONLY) int extmem2[100]; main() { /* Transfer 100 words from external memory to internal memory */ read_extmem(intmem1, extmem1, 100); /* Transfer 100 words from external memory to internal memory */ write_extmem(intmem2, extmem2, 100); } requires a customized . file containing a section, This examplethat resides in external memory. ldf seg_extmem, See Also write_extmem 1-348 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library realloc Change memory allocation Synopsis #include void *realloc (void *ptr, size_t size); Description The realloc function changes the memory allocation of the object pointed to by ptr to size. Initial values for the new object are taken from those in the object pointed to by ptr: * If the size of the new object is greater than the size of the object pointed to by ptr, then the values in the newly allocated section are undefined. * If ptr is a non-null pointer that was not allocated with one of the heap functions, the behavior is undefined. * If ptr is a null pointer, realloc imitates malloc. If size is zero and ptr is not a null pointer, realloc imitates free. * If ptr is not a null pointer, then the object is re-allocated from the heap that the object was originally allocated from. * If ptr is a null pointer, then the object is allocated from the current heap, which is the default heap unless heap_switch has been called to change the current heap to an alternate heap. Error Conditions If memory cannot be allocated, ptr remains unchanged and realloc returns a null pointer. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-349 Documented Library Functions Example #include int *ptr; ptr = (int *)malloc (10); /* allocate array of 10 words */ ptr = (int *)realloc (ptr, 20); /* change size to 20 words */ See Also calloc, free, heap_calloc, heap_free, heap_malloc, heap_realloc, malloc 1-350 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library remove Remove file Synopsis #include int remove(const char *filename); Description The remove function removes the file whose name is filename. After the function call, filename will no longer be accessible. The remove function is delegated to the current default device driver. The remove function returns zero on successful completion. Error Conditions If the remove function is unsuccessful, a non-zero value is returned. Example #include void remove_example(char *filename) { if (remove(filename)) printf("Remove of %s failed\n", filename); else printf("File %s removed\n", filename); } See Also rename CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-351 Documented Library Functions rename Rename a file Synopsis #include int rename(const char *oldname, const char *newname); Description The rename function will establish a new name, using the string newname, for a file currently known by the string oldname. After a successful rename, the file will no longer be accessible by oldname. The rename function is delegated to the current default device driver. If rename is successful, a value of zero is returned. Error Conditions If rename fails, the file named oldname is unaffected and a non-zero value is returned. Example #include void rename_file(char *new, char *old) { if (rename(old, new)) printf("rename failed for %s\n", old); else printf("%s now named %s\n", old, new); } 1-352 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also remove CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-353 Documented Library Functions rewind Reset file position indicator in a stream Synopsis #include void rewind(FILE *stream); Description The rewind function sets the file position indicator for stream to the beginning of the file. This is equivalent to using the fseek routine in the following manner: fseek(stream, 0, SEEK_SET); with the exception that rewind will also clear the error indicator. Error Conditions None. Example #include char buffer[20]; void rewind_example(FILE *fp) { /* write "a string" to a file */ fputs("a string", fp); /* rewind the file to the beginning */ rewind(fp); /* read back from the file - buffer will be "a string" */ fgets(buffer, sizeof(buffer), fp); } 1-354 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also fseek CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-355 Documented Library Functions roundfx Round a fixed-point value to a specified precision Synopsis #include short fract roundhr(short fract f, int n); fract roundr(fract f, int n); long fract roundlr(long fract f, int n); unsigned short fract rounduhr(unsigned short fract f, int n); unsigned fract roundur(unsigned fract f, int n); unsigned long fract roundulr(unsigned long fract f, int n); Description The roundfx family of functions round a fixed-point value to the number of fractional bits specified by the second argument. The rounding is round-to-nearest. If the rounded result is out of range of the result type, the result is saturated to the maximum or minimum fixed-point value. In addition to the individually-named functions for each fixed-point type, a type-generic macro roundfx is defined for use in C99 mode. This may be used with any of the fixed-point types and returns a result of the same type as its operand. Error Conditions None. Example #include long fract f; f = roundulr(0x12345678p-32ulr, 16); /* f == 0x12340000ulr */ f = roundfx(0x12345678p-32ulr, 16); /* f == 0x12340000ulr */ 1-356 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also No related functions. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-357 Documented Library Functions scanf Convert formatted input from stdin Synopsis #include int scanf(const char *format, /* args */...); Description The scanf function reads from the standard input stream stdin, interprets the inputs according to format and stores the results of the conversions in its arguments. The string pointed to by format contains the control format for the input with the arguments that follow being pointers to the locations where the converted results are to be written to. The scanf function is equivalent to calling fscanf with stdin as its first argument. For details on the control format string refer to fscanf. The scanf function returns number of successful conversions performed. Error Conditions The scanf function will return EOF if it encounters an error before any conversions are performed. Example #include void scanf_example(void) { short int day, month, year; char string[20]; /* Scan a string from standard input */ 1-358 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library scanf ("%s", string); /* Scan a date with any separator, eg, 1-1-2006 or 1/1/2006 */ scanf ("%hd%*c%hd%*c%hd", &day, &month, &year); } See Also fscanf CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-359 Documented Library Functions setbuf Specify full buffering for a stream Synopsis #include void setbuf(FILE *stream, char* buf); Description The setbuf function results in the array pointed to by buf being used to buffer the stream pointed to by stream instead of an automatically allocated buffer. The setbuf function may be used only after the stream pointed to by stream is opened but before it is read or written to. Note that the buffer provided must be of size BUFSIZ as defined in the stdio.h header. the buffer contains data for a text stream (either input data When or output data), the information is held in the form of 8-bit characters that are packed into 32-bit memory locations. Due to internal mechanisms used to unpack and pack this data, the I/O buffer must not reside at a memory location greater than the address 0x3fffffff. If buf is the NULL pointer, the input/output will be completely unbuffered. Error Conditions None. 1-360 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Example #include #include void* allocate_buffer_from_heap(FILE* fp) { /* Allocate a buffer from the heap for the file pointer */ void* buf = malloc(BUFSIZ); if (buf != NULL) setbuf(fp, buf); return buf; } See Also setvbuf CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-361 Documented Library Functions setjmp Define a run-time label Synopsis #include int setjmp (jmp_buf env); Description The setjmp function saves the calling environment in the jmp_buf argument. The effect of the call is to declare a run-time label that can be jumped to via a subsequent call to longjmp. When setjmp is called, it immediately returns with a result of zero to indicate that the environment has been saved in the jmp_buf argument. If, at some later point, longjmp is called with the same jmp_buf argument, longjmp restores the environment from the argument. The execution is then resumed at the statement immediately following the corresponding call to setjmp. The effect is as if the call to setjmp has returned for a second time but this time the function returns a non-zero result. The effect of calling longjmp is undefined if the function that called setjmp has returned in the interim. use of and (or similar functions which do not The follow conventional C/C++ flow control) may produce unexpected setjmp longjmp results when the application is compiled with optimizations enabled under certain circumstances. Functions that call setjmp or longjmp are optimized by the compiler with the assumption that all variables referenced may be modified by any functions that are called. This assumption ensures that it is safe to use setjmp and longjmp with optimizations enabled, though it does mean that it is dangerous to conceal from the optimizer that a call to setjmp or longjmp is being made, for example by calling through a function pointer. 1-362 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Error Conditions None. Example See longjmp for an example. See Also longjmp CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-363 Documented Library Functions setlocale Set the current locale Synopsis #include char *setlocale (int category, const char *locale); Description The setlocale function uses the parameters category and locale to select a current locale. The possible values for the category argument are those macros defined in locale.h beginning with "LC_". The only locale argument supported at this time is the "C" locale. If a null pointer is used for the locale argument, setlocale returns a pointer to a string which is the current locale for the given category argument. A subsequent call to setlocale with the same category argument and the string supplied by the previous setlocale call returns the locale to its original status. The string pointed to may not be altered by the program but may be overwritten by subsequent setlocale calls. Error Conditions None. Example #include setlocale (LC_ALL, "C"); /* sets the locale to the "C" locale */ See Also localeconv 1-364 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library setvbuf Specify buffering for a stream Synopsis #include int setvbuf(FILE *stream, char *buf, int type, size_t size); Description The setvbuf function may be used after a stream has been opened but before it is read or written to. The kind of buffering that is to be used is specified by the type argument. The valid values for type are detailed in the following table. Type Effect _IOFBF Use full buffering for output. Only output to the host system when the buffer is full, or when the stream is flushed or closed, or when a file positioning operation intervenes. _IOLBF Use line buffering. The buffer will be flushed whenever a NEWLINE is written, as well as when the buffer is full, or when input is requested. _IONBF Do not use any buffering at all. If buf is not the NULL pointer, the array it points to will be used for buffering, instead of an automatically allocated buffer. Note that if buf is non-NULL then you must ensure that the associated storage continues to be available until you close the stream identified by stream. The size argument specifies the size of the buffer required. If input/output is unbuffered, the buf and size arguments are ignored. the buffer contains data for a text stream (either input data When or output data), the information is held in the form of 8-bit characters that are packed into 32-bit memory locations. Due to internal CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-365 Documented Library Functions mechanisms used to unpack and pack this data, the I/O buffer must not reside at a memory location greater than the address 0x3fffffff. If buf is the NULL pointer, buffering is enabled and a buffer of size size will be automatically generated. The setvbuf function returns zero when successful. Error Conditions The setvbuf function will return a non-zero value if either an invalid value is given for type, or if the stream has already been used to read or write data, or if an I/O buffer could not be allocated. Example #include void line_buffer_stderr(void) { /* stderr is not buffered - set to use line buffering */ setvbuf (stderr,NULL,_IOLBF,BUFSIZ); } See Also setbuf 1-366 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library signal Define signal handling Synopsis #include void (*signal (int sig, void (*func)(int))) (int); Description The signal function determines how to handle a signal that is triggered by the raise or abort functions. The specified function func can be associated with one of the sig values listed in Table 1-41. The function is not thread-safe. Table 1-41. Valid Values for Parameter sig Sig Value Meaning, according to ISO/IEC 9899:1999 Standard SIGTERM Request for program termination. SIGABRT Program is terminating abnormally. SIGFPE Arithmetic operation was erroneous, e.g. division by zero. SIGILL Illegal instruction, or equivalent. SIGINT Request for interactive attention. SIGSEGV Access to invalid memory. the interpretations of the sig values listed in Table 1-41, Despite the signal function has no effect on the processor's interrupt mechanism. Any function registered via the signal function will only be invoked if done so explicitly, via the function abort or the function raise. For information on handling processor interrupts, see the System Run-Time Documentation in the online help. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-367 Documented Library Functions The func parameter may be one of the values listed in Table 1-42, instead of a pointer to a function. Table 1-42. Additional Valid Values for Parameter func func Value Meaning SIG_DFL Default behavior: do nothing if the signal is triggered by raise or abort. SIG_ERR An error occurred. SIG_IGN Ignore the signal if triggered by raise or abort. Return Value The signal function returns the value of the previously installed signal or signal handler action. Error Conditions The signal function returns SIG_ERR and sets errno to SIG_ERR if it does not recognize the requested signal. Example #include signal (SIGABRT, abort_handler); /* enable abort signal signal (SIGABRT, SIG_IGN); /* disable abort signal */ */ See Also abort, raise 1-368 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library sin Sine Synopsis #include float sinf (float x); double sin (double x); long double sind (long double x); Description The sin functions return the sine of x. The input is interpreted as radians; the output is in the range [-1, 1]. Error Conditions The input argument x for sinf must be in the domain [-1.647e6, 1.647e6] and the input argument for sind must be in the domain [-8.433e8, 8.433e8]. The functions return zero if x is outside their domain. Example #include double y; float x; y = sin (3.14159); /* y = 0.0 */ x = sinf (3.14159); /* x = 0.0 */ See Also asin, cos CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-369 Documented Library Functions sinh Hyperbolic sine Synopsis #include float sinhf (float x); double sinh (double x); long double sinhd (long double x); Description The hyperbolic sine functions return the hyperbolic sine of x. Error Conditions The input argument x must be in the domain [-89.39, 89.39] for sinhf, and in the domain [-710.44, 710.44] for sinhd. If the input value is greater than the function's domain, then HUGE_VAL is returned, and if the input value is less than the domain, then -HUGE_VAL is returned. Example #include float x; double y; x = sinhf ( 1.0); /* x = y = sinh /* y = -1.1752 */ (-1.0); 1.1752 */ See Also cosh 1-370 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library snprintf Format data into an n-character array Synopsis #include int snprintf (char *str, size_t n, const char *format, ...); Description The snprintf function is a function that is defined in the C99 Standard (ISO/IEC 9899). It is similar to the sprintf function in that snprintf formats data according to the argument format, and then writes the output to the array str. The argument format contains a set of conversion specifiers, directives, and ordinary characters that are used to control how the data is formatted. Refer to fprintf (on page 1-217) for a description of the valid format specifiers. The function differs from sprintf in that no more than n-1 characters are written to the output array. Any data written beyond the n-1'th character is discarded. A terminating NUL character is written after the end of the last character written to the output array unless n is set to zero, in which case nothing will be written to the output array and the output array may be represented by the NULL pointer. The snprintf function returns the number of characters that would have been written to the output array str if n was sufficiently large. The return value does not include the terminating null character written to the array. The output array will contain all of the formatted text if the return value is not negative and is also less than n. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-371 Documented Library Functions Error Conditions The snprintf function returns a negative value if a formatting error occurred. Example #include #include extern char *make_filename(char *name, int id) { char *filename_template = "%s%d.dat"; char *filename = NULL; int len = 0; int r; /* return value from snprintf */ do { r = snprintf(filename,len,filename_template,name,id); if (r < 0) /* formatting error? */ abort(); if (r < len) /* was complete string written? */ return filename; /* return with success */ filename = realloc(filename,(len=r+1)); } while (filename != NULL); abort(); } See Also fprintf, sprintf, vsnprintf 1-372 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library space_unused Space unused in heap Synopsis #include int space_unused(void); Description The space_unused function returns the size of the total amount of free space for the default heap. Note that calling malloc(space_unused()) does not allocate space because each allocated block uses more memory internally than the requested space, and also the free space in the heap may be fragmented, and thus not be available in one contiguous block. Error Conditions If there are no heaps, calling this function will return -1. Example #include int free_space; /* Get amount of free space in the heap */ free_space = space_unused(); See Also calloc, free,heap_calloc, heap_free, heap_init, heap_install, heap_lookup, heap_malloc, heap_space_unused, malloc, realloc CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-373 Documented Library Functions sprintf Format data into a character array Synopsis #include int sprintf (char *str, const char *format, /* args */...); Description The sprintf function formats data according to the argument format, and then writes the output to the array str. The argument format contains a set of conversion specifiers, directives, and ordinary characters that are used to control how the data is formatted. Refer to fprintf (on page 1-217) for a description of the valid format specifiers. In all respects other than writing to an array rather than a stream the behavior of sprintf is similar to that of fprintf. If the sprintf function is successful it will return the number of characters written in the array, not counting the terminating NULL character. Error Conditions The sprintf function returns a negative value if a formatting error occurred. Example #include #include char filename[128]; 1-374 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library extern char *assign_filename(char *name) { char *filename_template = "%s.dat"; int r; /* return value from sprintf */ if ((strlen(name)+5) > sizeof(filename)) abort(); r = sprintf(filename, filename_template, name); if (r < 0) /* sprintf failed */ abort(); return filename; /* return with success */ } See Also fprintf, snprintf CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-375 Documented Library Functions sqrt Square root Synopsis #include float sqrtf (float x); double sqrt (double x); long double sqrtd (long double x); Description The square root functions return the positive square root of x. Error Conditions The square root functions return zero for negative input values and set errno to EDOM to indicate a domain error. Example #include double y; float x; y = sqrt (2.0); /* y = 1.414..... */ x = sqrtf (2.0); /* x = 1.414..... */ See Also rsqrt 1-376 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library srand Random number seed Synopsis #include void srand (unsigned int seed); Description The srand function is used to set the seed value for the rand function. A particular seed value always produces the same sequence of pseudo-random numbers. Error Conditions None. Example #include srand (22); See Also rand CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-377 Documented Library Functions sscanf Convert formatted input in a string Synopsis #include int sscanf(const char *s, const char *format, /* args */...); Description The sscanf function reads from the string s. The function is equivalent to fscanf with the exception of the string being read from a string rather than a stream. The behavior of sscanf when reaching the end of the string equates to fscanf reaching the EOF in a stream. For details on the control format string, refer to fscanf. The sscanf function returns the number of items successfully read. Error Conditions If the sscanf function is unsuccessful, EOF is returned. Example #include void sscanf_example(const char *input) { short int day, month, year; char string[20]; /* Scan for a string from "input" */ sscanf (input, "%s", string); /* Scan a date with any separator, eg, 1-1-2006 or 1/1/2006 */ sscanf (input, "%hd%*c%hd%*c%hd", &day, &month, &year); } 1-378 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also fscanf CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-379 Documented Library Functions strcat Concatenate strings Synopsis #include char *strcat (char *s1, const char *s2); Description The strcat function appends a copy of the null-terminated string pointed to by s2 to the end of the null-terminated string pointed to by s1. It returns a pointer to the new s1 string, which is null-terminated. The behavior of strcat is undefined if the two strings overlap. Error Conditions None. Example #include char string1[50]; string1[0] = 'A'; string1[1] = 'B'; string1[2] = '\0'; strcat (string1, "CD"); /* new string is "ABCD" */ See Also strncat 1-380 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library strchr Find first occurrence of character in string Synopsis #include char *strchr (const char *s1, int c); Description The strchr function returns a pointer to the first location in s1, a null-terminated string, that contains the character c. Error Conditions The strchr function returns a null pointer if c is not part of the string. Example #include char *ptr1, *ptr2; ptr1 = "TESTING"; ptr2 = strchr (ptr1, 'E'); /* ptr2 points to the E in TESTING */ See Also memchr, strrchr CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-381 Documented Library Functions strcmp Compare strings Synopsis #include int strcmp (const char *s1, const char *s2); Description The strcmp function lexicographically compares the null-terminated strings pointed to by s1 and s2. It returns a positive value if the s1 string is greater than the s2 string, a negative value if the s2 string is greater than the s1 string, and a zero if the strings are the same. Error Conditions None. Example #include char string1[50], string2[50]; if (strcmp (string1, string2)) printf ("%s is different than %s \n", string1, string2); See Also memchr, strcmp 1-382 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library strcoll Compare strings Synopsis #include int strcoll (const char *s1, const char *s2); Description The strcoll function compares the string pointed to by s1 with the string pointed to by s2. The comparison is based on the locale macro, LC_COLLATE. Because only the C locale is defined in the ADSP-21xxx run-time environment, the strcoll function is identical to the strcmp function. The function returns a positive value if the s1 string is greater than the s2 string, a negative value if the s2 string is greater than the s1 string, and a zero if the strings are the same. Error Conditions None. Example #include char string1[50], string2[50]; if (strcoll (string1, string2)) printf ("%s is different than %s \n", string1, string2); See Also strcmp, strncmp CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-383 Documented Library Functions strcpy Copy from one string to another Synopsis #include char *strcpy (char *s1, const char *s2); Description The strcpy function copies the null-terminated string pointed to by s2 into the space pointed to by s1. Memory allocated for s1 must be large enough to hold s2, plus one space for the null character ('\0'). The behavior of strcpy is undefined if the two objects overlap or if s1 is not large enough. The strcpy function returns the new s1. Error Conditions None. Example #include char string1[50]; strcpy (string1, "SOMEFUN"); /* SOMEFUN is copied into string1 */ See Also memcpy, memmove, strncpy 1-384 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library strcspn Length of character segment in one string but not the other Synopsis #include size_t strcspn (const char *s1, const char *s2); Description The strcspn function returns the array index of the first character in s1 which is not in the set of characters pointed to by s2. The order of the characters in s2 is not significant. Error Conditions None. Example #include char *ptr1, *ptr2; size_t len; ptr1 = "Tried and Tested"; ptr2 = "aeiou"; len = strcspn (ptr1, ptr2); /* len = 2 */ See Also strlen, strspn CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-385 Documented Library Functions strerror Get string containing error message Synopsis #include char *strerror (int errnum); Description The strerror function is called to return a pointer to an error message that corresponds to the argument errnum. The global variable errno is commonly used as the value of errnum, and as errno is generally not supported by the library, strerror will always return a pointer to the string "There are no error strings defined!". Error Conditions None. Example #include char *ptr1; ptr1 = strerror (1); See Also No related functions. 1-386 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library strftime Format a broken-down time Synopsis #include size_t strftime(char *buf, size_t buf_size, const char *format, const struct tm *tm_ptr); Description The strftime function formats the broken-down time tm_ptr into the char array pointed to by buf, under the control of the format string format. At most, buf_size characters (including the null terminating character) are written to buf. In a similar way as for printf, the format string consists of ordinary characters, which are copied unchanged to the char array buf, and zero or more conversion specifiers. A conversion specifier starts with the character % and is followed by a character that indicates the form of transformation required - the supported transformations are given below in Table 1-43. Note that the strftime function only supports the "C" locale, and this is reflected in the table. Table 1-43. Conversion Specifiers Supported by strftime Conversion Specifier Transformation ISO/IEC 9899 %a abbreviated weekday name yes %A full weekday name yes %b abbreviated month name yes %B full month name yes CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-387 Documented Library Functions Table 1-43. Conversion Specifiers Supported by strftime (Cont'd) Conversion Specifier Transformation ISO/IEC 9899 %c date and time presentation in the form of DDD MMM dd hh:mm:ss yyyy yes %C century of the year POSIX.2-1992 + ISO C99 %d day of the month (01 - 31) yes %D date represented as mm/dd/yy POSIX.2-1992 + ISO C99 %e day of the month, padded with a space character (cf %d) POSIX.2-1992 + ISO C99 %F date represented as yyyy-mm-dd POSIX.2-1992 + ISO C99 %h abbreviated name of the month (same as POSIX.2-1992 + ISO C99 %b) %H hour of the day as a 24-hour clock (00-23) yes %I hour of the day as a 12-hour clock (00-12) yes %j day of the year (001-366) yes %k hour of the day as a 24-hour clock padded with a space ( 0-23) no %l hour of the day as a 12-hour clock padded with a space (0-12) no %m month of the year (01-12) yes %M minute of the hour (00-59) yes %n newline character POSIX.2-1992 + ISO C99 %p AM or PM yes %P am or pm no %r time presented as either hh:mm:ss AM or POSIX.2-1992 + ISO C99 as hh:mm:ss PM %R time presented as hh:mm POSIX.2-1992 + ISO C99 %S second of the minute (00-61) yes %t tab character POSIX.2-1992 + ISO C99 1-388 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Table 1-43. Conversion Specifiers Supported by strftime (Cont'd) Conversion Specifier Transformation ISO/IEC 9899 %T time formatted as %H:%M:%S POSIX.2-1992 + ISO C99 %U week number of the year (week starts on yes Sunday) (00-53) %w weekday as a decimal (0-6) (0 if Sunday) yes %W week number of the year (week starts on yes Sunday) (00-53) %x date represented as mm/dd/yy (same as %D) yes %X time represented as hh:mm:ss yes %y year without the century (00-99) yes %Y year with the century (nnnn) yes %Z the time zone name, or nothing if the name cannot be determined yes %% % character yes The current implementation of does not support time zones and, therefore, the specifier does not generate any characters. time.h %Z The strftime function returns the number of characters (not including the terminating null character) that have been written to buf. Error Conditions The strftime function returns zero if more than buf_size characters are required to process the format string. In this case, the contents of the array buf will be indeterminate. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-389 Documented Library Functions Example #include #include extern void print_time(time_t tod) { char tod_string[100]; strftime(tod_string, 100, "It is %M min and %S secs after %l o'clock (%p)", gmtime(&tod)); puts(tod_string); } See Also ctime, gmtime, localtime, mktime 1-390 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library strlen String length Synopsis #include size_t strlen (const char *s1); Description The strlen function returns the length of the null-terminated string pointed to by s1 (not including the terminating null character). Error Conditions None. Example #include size_t len; len = strlen ("SOMEFUN"); /* len = 7 */ See Also strcspn, strspn CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-391 Documented Library Functions strncat Concatenate characters from one string to another Synopsis #include char *strncat (char *s1, const char *s2, size_t n); Description The strncat function appends a copy of up to n characters in the null-terminated string pointed to by s2 to the end of the null-terminated string pointed to by s1. It returns a pointer to the new s1 string. The behavior of strncat is undefined if the two strings overlap. The new s1 string is terminated with a null character ('\0'). Error Conditions None. Example #include char string1[50], *ptr; string1[0] = '\0'; strncat (string1, "MOREFUN", 4); /* string1 equals "MORE" */ See Also strncat 1-392 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library strncmp Compare characters in strings Synopsis #include int strncmp (const char *s1, const char *s2, size_t n); Description The strncmp function lexicographically performs the comparison on the first n characters of the null-terminated strings pointed to by s1 and s2. It returns a positive value if the s1 string is greater than the s2 string, a negative value if the s2 string is greater than the s1 string, and a zero if the strings are the same. Error Conditions None. Example #include char *ptr1; ptr1 = "TEST1"; if (strncmp (ptr1, "TEST", 4) == 0) printf ("%s starts with TEST\n", ptr1); See Also memcmp, strcmp CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-393 Documented Library Functions strncpy Copy characters from one string to another Synopsis #include char *strncpy (char *s1, const char *s2, size_t n); Description The strncpy function copies up to n characters of the null-terminated string, starting with element 0, pointed to by s2 into the space pointed to by s1. If the last character copied from s2 is not a null, the result does not end with a null. The behavior of strncpy is undefined if the two objects overlap. The strncpy function returns the new s1. If the s2 string contains fewer than n characters, the s1 string is padded with the null character until all n characters have been written. Error Conditions None. Example #include char string1[50]; strncpy (string1, "MOREFUN", 4); /* MORE is copied into string1 */ string1[4] = '\0'; /* must null-terminate string1 */ See Also memcpy, memmove, strcpy 1-394 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library strpbrk Find character match in two strings Synopsis #include char *strpbrk (const char *s1, const char *s2); Description The strpbrk function returns a pointer to the first character in s1 that is also found in s2. The string pointed to by s2 is treated as a set of characters. The order of the characters in the string is not significant. Error Conditions In the event that no character in s1 matches any in s2, a null pointer is returned. Example #include char *ptr1, *ptr2, *ptr3; ptr1 = "TESTING"; ptr2 = "SHOP" ptr3 = strpbrk (ptr1, ptr2); /* ptr3 points to the S in TESTING */ See Also strspn CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-395 Documented Library Functions strrchr Find last occurrence of character in string Synopsis #include char *strrchr (const char *s1, int c); Description The strrchr function returns a pointer to the last occurrence of character c in the null-terminated input string s1. Error Conditions The strrchr function returns a null pointer if c is not found. Example #include char *ptr1, *ptr2; ptr1 = "TESTING"; ptr2 = strrchr (ptr1, 'T'); /* ptr2 points to the second T of TESTING */ See Also memchr, strchr 1-396 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library strspn Length of segment of characters in both strings Synopsis #include size_t strspn (const char *s1, const char *s2); Description The strspn function returns the length of the initial segment of s1, which consists entirely of characters in the string pointed to by s2. The string pointed to by s2 is treated as a set of characters. The order of the characters in the string is not significant. Error Conditions None. Example #include size_t len; char *ptr1, *ptr2; ptr1 = "TESTING"; ptr2 = "ERST"; len = strspn (ptr1, ptr2); /* len = 4 */ See Also strcspn, strlen CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-397 Documented Library Functions strstr Find string within string Synopsis #include char *strstr (const char *s1, const char *s2); Description The strstr function returns a pointer to the first occurrence in the string pointed to by s1 of the characters in the string pointed to by s2. This excludes the terminating null character in s1. Error Conditions If the string is not found, strstr returns a null pointer. If s2 points to a string of zero length, s1 is returned. Example #include char *ptr1, *ptr2; ptr1 = "TESTING"; ptr2 = strstr (ptr1, "E"); /* ptr2 points to the E in TESTING */ See Also strchr 1-398 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library strtod Convert string to double Synopsis #include double strtod(const char *nptr, char **endptr) Description The strtod function extracts a value from the string pointed to by nptr, and returns the value as a double. The strtod function expects nptr to point to a string that represents either a decimal floating-point number or a hexadecimal floating-point number. Either form of number may be preceded by a sequence of whitespace characters (as determined by the isspace function) that the function ignores. A decimal floating-point number has the form: [sign] [digits] [.digits] [{e|E} [sign] [digits]] The sign token is optional and is either plus ( + ) or minus ( - ); and digits are one or more decimal digits. The sequence of digits may contain a decimal point ( . ). The decimal digits can be followed by an exponent, which consists of an introductory letter (e or E) and an optionally signed integer. If neither an exponent part nor a decimal point appears, a decimal point is assumed to follow the last digit in the string. The form of a hexadecimal floating-point number is: [sign] [{0x}|{0X}] [hexdigs] [.hexdigs] [{p|P} [sign] [digits]] A hexadecimal floating-point number may start with an optional plus ( + ) or minus ( - ) followed by the hexadecimal prefix 0x or 0X. This character CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-399 Documented Library Functions sequence must be followed by one or more hexadecimal characters that optionally contain a decimal point ( . ). The hexadecimal digits are followed by a binary exponent that consists of the letter p or P, an optional sign, and a non-empty sequence of decimal digits. The exponent is interpreted as a power of two that is used to scale the fraction represented by the tokens [hexdigs] [.hexdigs]. The first character that does not fit either form of number stops the scan. If endptr is not NULL, a pointer to the character that stopped the scan is stored at the location pointed to by endptr. If no conversion can be performed, the value of nptr is stored at the location pointed to by endptr. Error Conditions The strtod function returns a zero if no conversion can be made and a pointer to the invalid string is stored in the object pointed to by endptr. If the correct value results in an overflow, a positive or negative (as appropriate) HUGE_VAL is returned. If the correct value results in an underflow, zero is returned. The ERANGE value is stored in errno in the case of either an overflow or underflow. Example #include char *rem; double dd; dd = strtod ("2345.5E4 abc",&rem); /* dd = 2.3455E+7, rem = " abc" */ dd = strtod ("-0x1.800p+9,123",&rem); /* dd = -768.0, rem = ",123" 1-400 */ CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also atof, strtofxfx, strtol, strtoul CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-401 Documented Library Functions strtofxfx Convert string to fixed-point Synopsis #include short fract strtofxhr(const char *nptr, char **endptr); fract strtofxr(const char *nptr, char **endptr); long fract strtofxlr(const char *nptr, char **endptr); unsigned short fract strtofxuhr(const char *nptr, char **endptr); unsigned fract strtofxur(const char *nptr, char **endptr); unsigned long fract strtofxulr(const char *nptr, char **endptr); Description The strtofxfx family of functions extracts a value from the string pointed to by nptr, and returns the value as a fixed-point. The strtofxfx functions expect nptr to point to a string that represents either a decimal floating-point number or a hexadecimal floating-point number. Either form of number may be preceded by a sequence of whitespace characters (as determined by the isspace function) that the function ignores. A decimal floating-point number has the form: [sign] [digits] [.digits] [{e|E} [sign] [digits]] The sign token is optional and is either plus ( + ) or minus ( - ); and digits are one or more decimal digits. The sequence of digits may contain a decimal point ( . ). The decimal digits can be followed by an exponent, which consists of an introductory letter (e or E) and an optionally signed integer. If neither an exponent part nor a decimal point appears, a decimal point is assumed to follow the last digit in the string. 1-402 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library The form of a hexadecimal floating-point number is: [sign] [{0x}|{0X}] [hexdigs] [.hexdigs] [{p|P} [sign] [digits]] A hexadecimal floating-point number may start with an optional plus ( + ) or minus ( - ) followed by the hexadecimal prefix 0x or 0X. This character sequence must be followed by one or more hexadecimal characters that optionally contain a decimal point ( . ). The hexadecimal digits are followed by a binary exponent that consists of the letter p or P, an optional sign, and a non-empty sequence of decimal digits. The exponent is interpreted as a power of two that is used to scale the fraction represented by the tokens [hexdigs] [.hexdigs]. The first character that does not fit either form of number stops the scan. If endptr is not NULL, a pointer to the character that stopped the scan is stored at the location pointed to by endptr. If no conversion can be performed, the value of nptr is stored at the location pointed to by endptr. Error Conditions The strtofxfx functions return a zero if no conversion can be made and a pointer to the invalid string is stored in the object pointed to by endptr. If the correct value results in an overflow, the maximum positive or negative (as appropriate) fixed-point value is returned. If the correct value results in an underflow, zero is returned. The ERANGE value is stored in errno in the case of overflow. Example #include char *rem; unsigned long fract ulr; ulr = strtofxulr ("0x180p-12,123",&rem); /* ulr = 0x1800p-16ulr, rem = ",123" CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors */ 1-403 Documented Library Functions See Also strtod, strtol, strtoul, strtoull 1-404 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library strtok Convert string to tokens Synopsis #include char *strtok (char *s1, const char *s2); Description The strtok function returns successive tokens from the string s1, where each token is delimited by characters from s2. A call to strtok with s1 not NULL returns a pointer to the first token in s1, where a token is a consecutive sequence of characters not in s2. s1 is modified in place to insert a null character at the end of the token returned. If s1 consists entirely of characters from s2, NULL is returned. Subsequent calls to strtok with s1 equal to NULL return successive tokens from the same string. When the string contains no further tokens, NULL is returned. Each new call to strtok may use a new delimiter string, even if s1 is NULL. If s1 is NULL, the remainder of the string is converted into tokens using the new delimiter characters. Error Conditions The strtok function returns a null pointer if there are no tokens remaining in the string. Example #include static char str[] = "a phrase to be tested, today"; char *t; CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-405 Documented Library Functions t = strtok (str, " "); /* t points to "a" */ t = strtok (NULL, " "); /* t points to "phrase" */ t = strtok (NULL, ","); /* t points to "to be tested" */ t = strtok (NULL, "."); /* t points to " today" */ t = strtok (NULL, "."); /* t = NULL */ See Also No related functions. 1-406 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library strtol Convert string to long integer Synopsis #include long int strtol (const char *nptr, char **endptr, int base); Description The strtol function returns as a long int the value represented by the string nptr. If endptr is not a null pointer, strtol stores a pointer to the unconverted remainder in *endptr. The strtol function breaks down the input into three sections: * White space (as determined by isspace) * Initial characters * Unrecognized characters including a terminating null character The initial characters may be composed of an optional sign character, 0x or 0X if base is 16, and those letters and digits which represent an integer with a radix of base. The letters (a-z or A-Z) are assigned the values 10 to 35, and their use is permitted only when those values are less than the value of base. If base is zero, then the base is taken from the initial characters. A leading 0x indicates base 16; a leading 0 indicates base 8. For any other leading characters, base 10 is used. If base is between 2 and 36, it is used as a base for conversion. Error Conditions The strtol function returns a zero if no conversion can be made and a pointer to the invalid string is stored in the object pointed to by endptr, CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-407 Documented Library Functions provided that endptr is not a null pointer. If the correct value results in an overflow, positive or negative (as appropriate) LONG_MAX is returned. If the correct value results in an underflow, LONG_MIN is returned. ERANGE is stored in errno in the case of either overflow or underflow. Example #include #define base 10 char *rem; long int i; i = strtol ("2345.5", &rem, base); /* i=2345, rem=".5" */ See Also atoi, atol, strtofxfx, strtoll, strtoul, strtoull 1-408 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library strtold Convert string to long double Synopsis #include long double strtold(const char *nptr, char **endptr) Description The strtold function extracts a value from the string pointed to by nptr, and returns the value as a long double. The strtold function expects nptr to point to a string that represents either a decimal floating-point number or a hexadecimal floating-point number. Either form of number may be preceded by a sequence of whitespace characters (as determined by the isspace function) that the function ignores. A decimal floating-point number has the form: [sign] [digits] [.digits] [{e|E} [sign] [digits]] The sign token is optional and is either plus ( + ) or minus ( - ); and digits are one or more decimal digits. The sequence of digits may contain a decimal point ( . ). The decimal digits can be followed by an exponent, which consists of an introductory letter (e or E) and an optionally signed integer. If neither an exponent part nor a decimal point appears, a decimal point is assumed to follow the last digit in the string. The form of a hexadecimal floating-point number is: [sign] [{0x}|{0X}] [hexdigs] [.hexdigs] [{p|P} [sign] [digits]] A hexadecimal floating-point number may start with an optional plus ( + ) or minus ( - ) followed by the hexadecimal prefix 0x or 0X. This character CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-409 Documented Library Functions sequence must be followed by one or more hexadecimal characters that optionally contain a decimal point ( . ). The hexadecimal digits are followed by a binary exponent that consists of the letter p or P, an optional sign, and a non-empty sequence of decimal digits. The exponent is interpreted as a power of two that is used to scale the fraction represented by the tokens [hexdigs] [.hexdigs]. The first character that does not fit either form of number stops the scan. If endptr is not NULL, a pointer to the character that stopped the scan is stored at the location pointed to by endptr. If no conversion can be performed, the value of nptr is stored at the location pointed to by endptr. Error Conditions The strtold function returns a zero if no conversion can be made and a pointer to the invalid string is stored in the object pointed to by endptr. If the correct value results in an overflow, a positive or negative (as appropriate) LDBL_MAX is returned. If the correct value results in an underflow, zero is returned. The ERANGE value is stored in errno in the case of either an overflow or underflow. Example #include char *rem; long double dd; dd = strtold ("2345.5E4 abc",&rem); /* dd = 2.3455E+7, rem = " abc" */ dd = strtold ("-0x1.800p+9,123",&rem); /* dd = -768.0, rem = ",123" 1-410 */ CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library See Also atoi, atol, strtod, strtofxfx, strtoul CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-411 Documented Library Functions strtoll Convert string to long long integer Synopsis #include long long strtoll (const char *nptr, char **endptr, int base); Description The strtoll function returns as a long long the value represented by the string nptr. If endptr is not a null pointer, strtoll stores a pointer to the unconverted remainder in *endptr. The strtoll function breaks down the input into three sections: * White space (as determined by isspace) * Initial characters * Unrecognized characters including a terminating null character The initial characters may be composed of an optional sign character, 0x or 0X if base is 16, and those letters and digits which represent an integer with a radix of base. The letters (a-z or A-Z) are assigned the values 10 to 35, and their use is permitted only when those values are less than the value of base. If base is zero, then the base is taken from the initial characters. A leading 0x indicates base 16; a leading 0 indicates base 8. For any other leading characters, base 10 is used. If base is between 2 and 36, it is used as a base for conversion. Error Conditions The strtoll function returns a zero if no conversion can be made and a pointer to the invalid string is stored in the object pointed to by endptr, 1-412 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library provided that endptr is not a null pointer. If the correct value results in an overflow, positive or negative (as appropriate) LLONG_MAX is returned. If the correct value results in an underflow, LLONG_MIN is returned. ERANGE is stored in errno in the case of either overflow or underflow. Example #include #define base 10 char *rem; long long i; i = strtoll ("2345.5", &rem, base); /* i=2345, rem=".5" */ See Also atoi, atol, strtol, strtoul, strtoull CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-413 Documented Library Functions strtoul Convert string to unsigned long integer Synopsis #include unsigned long int strtoul (const char *nptr, char **endptr, int base); Description The strtoul function returns as an unsigned long int the value represented by the string nptr. If endptr is not a null pointer, strtoul stores a pointer to the unconverted remainder in *endptr. The strtoul function breaks down the input into three sections: * White space (as determined by isspace) * Initial characters * Unrecognized characters including a terminating null character The initial characters may comprise an optional sign character, 0x or 0X, when base is 16, and those letters and digits which represent an integer with a radix of base. The letters (a-z or A-Z) are assigned the values 10 to 35, and are permitted only when those values are less than the value of base. If base is zero, then the base is taken from the initial characters. A leading 0x indicates base 16; a leading 0 indicates base 8. For any other leading characters, base 10 is used. If base is between 2 and 36, it is used as a base for conversion. 1-414 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Error Conditions The strtoul function returns a zero if no conversion can be made and a pointer to the invalid string is stored in the object pointed to by endptr, provided that endptr is not a null pointer. If the correct value results in an overflow, ULONG_MAX is returned. ERANGE is stored in errno in the case of overflow. Example #include #define base 10 char *rem; unsigned long int i; i = strtoul ("2345.5", &rem, base); /* i = 2345, rem = ".5" */ See Also atoi, atol, strtofxfx, strtol, strtoll, strtoull CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-415 Documented Library Functions strtoull Convert string to unsigned long long integer Synopsis #include unsigned long long strtoull (const char char *nptr, **endptr, int base); Description The strtoull function returns as an unsigned long long the value represented by the string nptr. If endptr is not a null pointer, strtoul stores a pointer to the unconverted remainder in *endptr. The strtoull function breaks down the input into three sections: * White space (as determined by isspace) * Initial characters * Unrecognized characters including a terminating null character The initial characters may comprise an optional sign character, 0x or 0X, when base is 16, and those letters and digits which represent an integer with a radix of base. The letters (a-z or A-Z) are assigned the values 10 to 35, and are permitted only when those values are less than the value of base. If base is zero, then the base is taken from the initial characters. A leading 0x indicates base 16; a leading 0 indicates base 8. For any other leading characters, base 10 is used. If base is between 2 and 36, it is used as a base for conversion. 1-416 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Error Conditions The strtoull function returns a zero if no conversion can be made and a pointer to the invalid string is stored in the object pointed to by endptr, provided that endptr is not a null pointer. If the correct value results in an overflow, ULLONG_MAX is returned. ERANGE is stored in errno in the case of overflow. Example #include #define base 10 char *rem; unsigned long long i; i = strtoull ("2345.5", &rem, base); /* i = 2345, rem = ".5" */ See Also atoi, atol, strtofxfx, strtol, strtoll, strtoul CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-417 Documented Library Functions strxfrm Transform string using LC_COLLATE Synopsis #include size_t strxfrm (char *s1, const char *s2, size_t n); Description The strxfrm function transforms the string pointed to by s2 using the locale specific category LC_COLLATE. (See setlocale). It places the result in the array pointed to by s1. The transformation is such that if and were transformed and used as arguments to , the result would be identical to the s1 s2 strcmp result derived from strcoll using s1 and s2 as arguments. However, since only C locale is implemented, this function does not perform any transformations other than the number of characters. The string stored in the array pointed to by s1 is never more than n characters including the terminating NULL character. strxfrm returns 1. If this returned value is n or greater, the result stored in the array pointed to by s1 is indeterminate. s1 can be a NULL pointer if n is zero. Error Conditions None. 1-418 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library Example #include char string1[50]; strxfrm (string1, "SOMEFUN", 49); /* SOMEFUN is copied into string1 */ See Also setlocale, strcmp, strcoll CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-419 Documented Library Functions system Send string to operating system Synopsis #include int system (const char *string); Description The system function normally sends a string to the operating system. In the context of the ADSP-21xxx run-time environment, system always returns zero. Error Conditions None. Example #include system ("string"); /* always returns zero */ See Also getenv 1-420 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library tan Tangent Synopsis #include float tanf (float x); double tan (double x); long double tand (long double x); Description The tangent functions return the tangent of the argument x, where x is measured in radians. Error Conditions The domain of tanf is [-1.647e6, 1.647e6], and the domain for tand is [-4.21657e8, 4.21657e8]. The functions return 0.0 if the input argument x is outside the respective domains. Example #include double y; float x; y = tan (3.14159/4.0); /* y = 1.0 */ x = tanf (3.14159/4.0); /* x = 1.0 */ See Also atan, atan2 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-421 Documented Library Functions tanh Hyperbolic tangent Synopsis #include float tanhf (float x); double tanh (double x); long double tanhd (long double x); Description The hyperbolic tangent functions return the hyperbolic tangent of the argument x, where x is measured in radians. Error Conditions None. Example #include double x, y; float z, w; y = tanh (x); z = tanhf (w); See Also cosh, sinh 1-422 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library time Calendar time Synopsis #include time_t time(time_t *t); Description The time function returns the current calendar time which measures the number of seconds that have elapsed since the start of a known epoch. As the calendar time cannot be determined in this implementation of time.h, a result of (time_t) -1 is returned. The function's result is also assigned to its argument, if the pointer to t is not a null pointer. Error Conditions The time function will return the value ((time_t) time is not available. -1) if the calendar Example #include #include if (time(NULL) == (time_t) -1) printf("Calendar time is not available\n"); See Also ctime, gmtime, localtime CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-423 Documented Library Functions tolower Convert from uppercase to lowercase Synopsis #include int tolower (int c); Description The tolower function converts the input character to lowercase if it is uppercase; otherwise, it returns the character. Error Conditions None. Example #include int ch; for (ch = 0; ch <= 0x7f; ch++) { printf ("%#04x", ch); if (isupper (ch)) printf ("tolower=%#04x", tolower (ch)); putchar ('\n'); } See Also islower, isupper, toupper 1-424 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library toupper Convert from lowercase to uppercase Synopsis #include int toupper (int c); Description The toupper function converts the input character to uppercase if it is in lowercase; otherwise, it returns the character. Error Conditions None. Example #include int ch; for (ch = 0; ch <= 0x7f; ch++) { printf ("%#04x", ch); if (islower (ch)) printf ("toupper=%#04x", toupper (ch)); putchar ('\n'); } See Also islower, isupper, tolower CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-425 Documented Library Functions ungetc Push character back into input stream Synopsis #include int ungetc(int uc, FILE *stream); Description The ungetc function pushes the character specified by uc back onto stream. The characters that have been pushed back onto stream will be returned by any subsequent read of stream in the reverse order of their pushing. A successful call to the ungetc function will clear the EOF indicator for stream. The file position indicator for stream is decremented for every successful call to ungetc. Upon successful completion, ungetc returns the character pushed back after conversion. Error Conditions If the ungetc function is unsuccessful, EOF is returned. Example #include void ungetc_example(FILE *fp) { int ch, ret_ch; /* get char from file pointer */ ch = fgetc(fp); /* unget the char, return value should be char */ 1-426 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library if ((ret_ch = ungetc(ch, fp)) != ch) printf("ungetc failed\n"); /* make sure that the char had been placed in the file */ if ((ret_ch = fgetc(fp)) != ch) printf("ungetc failed to put back the char\n"); } See Also fseek, fsetpos, getc CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-427 Documented Library Functions va_arg Get next argument in variable-length list of arguments Synopsis #include void va_arg (va_list ap, type); Description The va_arg macro is used to walk through the variable length list of arguments to a function. After starting to process a variable-length list of arguments with va_start, call va_arg with the same va_list variable to extract arguments from the list. Each call to va_arg returns a new argument from the list. Substitute a type name corresponding to the type of the next argument for the type parameter in each call to va_arg. After processing the list, call va_end. The header file stdarg.h defines a pointer type called va_list that is used to access the list of variable arguments. The function calling va_arg is responsible for determining the number and types of arguments in the list. It needs this information to determine how many times to call va_arg and what to pass for the type parameter each time. There are several common ways for a function to determine this type of information. The standard C printf function reads its first argument looking for %-sequences to determine the number and types of its extra arguments. In the example below, all of the arguments are of the same type (char*), and a termination value (NULL) is used to indicate the end of the argument list. Other methods are also possible. 1-428 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library If a call to va_arg is made after all arguments have been processed, or if va_arg is called with a type parameter that is different from the type of the next argument in the list, the behavior of va_arg is undefined. Error Conditions None. Example #include #include #include #include char *concat(char *s1,...) { int len = 0; char *result; char *s; va_list ap; va_start (ap,s1); s = s1; while (s){ len += strlen (s); s = va_arg (ap,char *); } va_end (ap); result = malloc (len +7); if (!result) return result; *result = '\0'; va_start (ap,s1); CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-429 Documented Library Functions s = s1; while (s){ strcat (result,s); s = va_arg (ap,char *); } va_end (ap); return result; } char *txt1 = "One"; char *txt2 = "Two"; char *txt3 = "Three"; extern int main(void) { char *result; result = concat(txt1, txt2, txt3, NULL); puts(result); /* prints "OneTwoThree" */ free(result); } See Also va_end, va_start 1-430 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library va_end Finish variable-length argument list processing Synopsis #include void va_end (va_list ap); Description The va_end macro can only be invoked after the va_start macro has been invoked. A call to va_end concludes the processing of a variable-length list of arguments that was begun by va_start. Error Conditions None. Example Refer to va_arg for an example. See Also va_arg, va_start CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-431 Documented Library Functions va_start Initialize the variable-length argument list processing Synopsis #include void va_start (va_list ap, parmN); Description The va_start macro is used to start processing variable arguments in a function declared to take a variable number of arguments. The first argument to va_start should be a variable of type va_list, which is used by va_arg to walk through the arguments. The second argument is the name of the last named parameter in the function's parameter list; the list of variable arguments immediately follows this parameter. The va_start macro must be invoked before either the va_arg or va_end macro can be invoked. Error Conditions None. Example Refer to va_arg for an example. See Also va_arg, va_end 1-432 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library vfprintf Print formatted output of a variable argument list Synopsis #include #include int vfprintf(FILE *stream, const char *format, va_list ap); Description The vfprintf function formats data according to the argument format, and then writes the output to the stream stream. The argument format contains a set of conversion specifiers, directives, and ordinary characters that are used to control how the data is formatted. Refer to fprintf (on page 1-217) for a description of the valid format specifiers. The function behaves in the same manner as sprintf except that, instead of taking a variable number of arguments, it is called with an argument list ap of type va_list as defined in stdarg.h. If the vfprintf function is successful, it will return the number of characters output. Error Conditions The vfprintf function returns a negative value if unsuccessful. Example #include #include void write_name_to_file(FILE *fp, char *name_template, ...) { CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-433 Documented Library Functions va_list p_vargs; int ret; /* return value from vfprintf */ va_start (p_vargs,name_template); ret = vfprintf(fp, name_template, p_vargs); va_end (p_vargs); if (ret < 0) printf("vfprintf failed\n"); } See Also fprintf, va_start, va_end 1-434 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library vprintf Print formatted output of a variable argument list to stdout Synopsis #include #include int vprintf(const char *format, va_list ap); Description The vprintf function formats data according to the argument format, and then writes the output to the standard output stream stdout. The argument format contains a set of conversion specifiers, directives, and ordinary characters that are used to control how the data is formatted. Refer to fprintf (on page 1-217) for a description of the valid format specifiers. The vprintf function behaves in the same manner as vfprintf with stdout provided as the pointer to the stream. If the vprintf function is successful it will return the number of characters output. Error Conditions The vprintf function returns a negative value if unsuccessful. Example #include #include #include void print_message(int error, char *format, ...) CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-435 Documented Library Functions { /* This function is called with the same arguments as for */ /* printf but if the argument error is not zero, then the */ /* output will be preceded by the text "ERROR:" */ va_list p_vargs; int ret; /* return value from vprintf */ va_start (p_vargs, format); if (!error) printf("ERROR: "); ret = vprintf(format, p_vargs); va_end (p_vargs); if (ret < 0) printf("vprintf failed\n"); } See Also fprintf, vfprintf 1-436 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library vsnprintf Format argument list into an n-character array Synopsis #include #include int vsnprintf (char *str, size_t n, const char *format, va_list args); Description The vsnprintf function is similar to the vsprintf function in that it formats the variable argument list args according to the argument format, and then writes the output to the array str. The argument format contains a set of conversion specifiers, directives, and ordinary characters that are used to control how the data is formatted. Refer to fprintf (on page 1-217) for a description of the valid format specifiers. The function differs from vsprintf in that no more than n-1 characters are written to the output array. Any data written beyond the n-1'th character is discarded. A terminating NUL character is written after the end of the last character written to the output array unless n is set to zero, in which case nothing will be written to the output array and the output array may be represented by the NULL pointer. The vsnprintf function returns the number of characters that would have been written to the output array str if n was sufficiently large. The return value does not include the terminating NUL character written to the array. Error Conditions The vsnprintf function returns a negative value if unsuccessful. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-437 Documented Library Functions Example #include #include #include char *message(char *format, ...) { char *message = NULL; int len = 0; int r; va_list p_vargs; /* return value from vsnprintf */ do { va_start (p_vargs,format); r = vsnprintf (message,len,format,p_vargs); va_end (p_vargs); if (r < 0) /* formatting error? */ /* was complete string written? */ /* return with success */ abort(); if (r < len) return message; message = realloc (message,(len=r+1)); } while (message != NULL); abort(); } See Also fprintf, snprintf 1-438 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library vsprintf Format argument list into a character array Synopsis #include #include int vsprintf (char *str, const char *format, va_list args); Description The vsprintf function formats the variable argument list args according to the argument format, and then writes the output to the array str. The argument format contains a set of conversion specifiers, directives, and ordinary characters that are used to control how the data is formatted. Refer to fprintf (on page 1-217) for a description of the valid format specifiers. With one exception, the vsprintf function behaves in the same manner as sprintf. Instead of being a function that takes a variable number or an arguments function, it is called with an argument list args of type va_list, as defined in stdarg.h. The vsprintf function returns the number of characters that have been written to the output array str. The return value does not include the terminating NUL character written to the array. Error Conditions The vsprintf function returns a negative value if unsuccessful. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-439 Documented Library Functions Example #include #include #include char filename[128]; char *assign_filename(char *filename_template, ...) { char *message = NULL; int r; va_list p_vargs; /* return value from vsprintf */ va_start (p_vargs,filename_template); r = vsprintf(&filename[0], filename_template, p_vargs); va_end (p_vargs); if (r < 0) /* formatting error? */ /* return with success */ abort(); return &filename[0]; } See Also fprintf, sprintf, snprintf 1-440 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors C/C++ Run-Time Library write_extmem Write to external memory Synopsis #include <21261.h> #include <21262.h> #include <21266.h> #include <21362.h> #include <21363.h> #include <21364.h> #include <21365.h> #include <21366.h> void write_extmem(void *internal_address, void *external_address, size_t n); Description On ADSP-2126x and some ADSP-2136x processors, it is not possible for the core to access external memory directly. The write_extmem function copies data from internal to external memory. The write_extmem function will transfer n 32-bit words from internal_address to external_address. Error Conditions None. Example See read_extmem for a usage example. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 1-441 Documented Library Functions See Also read_extmem 1-442 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2 DSP RUN-TIME LIBRARY This chapter describes the DSP run-time library, which contains a broad collection of functions that are commonly required by signal processing applications. The services provided by the DSP run-time library include support for general-purpose signal processing such as companders, filters, and Fast Fourier Transform (FFT) functions. These services are Analog Devices extensions to ANSI standard C. For more information about the algorithms on which many of the DSP run-time library's math functions are based, see W. J. Cody and W. Waite, Software Manual for the Elementary Functions, Englewood Cliffs, New Jersey: Prentice Hall, 1980. The chapter contains the following: * DSP Run-Time Library Guide contains information about the library and provides a description of the DSP header files included with this release of the cc21k compiler. * DSP Run-Time Library Reference contains complete reference information for each DSP run-time library function included with this release of the cc21k compiler. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-1 DSP Run-Time Library Guide DSP Run-Time Library Guide The DSP run-time library contains routines that you can call from your source program. This section describes how to use the library and provides information on the following topics: * Calling DSP Library Functions * Reentrancy * Library Attributes * Working With Library Source Code * DSP Header Files * Built-In DSP Library Functions * Implications of Using SIMD Mode * Using Data in External Memory Calling DSP Library Functions To use a DSP run-time library function, call the function by name and provide the appropriate arguments. The names and arguments for each function are described in the function's reference page in DSP Run-Time Library Guide. Like other functions you use, library functions should be declared. Declarations are supplied in header files, as described in Working With Library Source Code. Note that C++ namespace prefixing is not supported when calling a DSP library function. All DSP library functions are in the C++ global namespace. 2-2 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library function names are C function names. If you call C run-time The library functions from an assembly language program, you must use the assembly version of the function name, which is the function name prefixed with an underscore. For more information on naming conventions, see the section "C/C++ and Assembly Interface" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors. You can use the archiver, described in the Linker and Utilities Manual, to build library archive files of your own functions. Reentrancy All the library functions in the DSP run-time library are re-entrant--they only operate on data passed in via a parameter and do not directly access non-constant static data. This means that the library may safely be used in a multi-threaded environment (such as with an RTOS). Library Attributes The DSP run-time library contains the same attributes as the C/C++ run-time library. For more information, see Library Attributes. Working With Library Source Code The source code for the functions in the C and DSP run-time libraries is provided with CCES, in the SHARC\lib\src subdirectory. The directory contains the source for the C run-time library, for the DSP run-time library, and for the I/O run-time library, as well as the source for the main program startup functions. The source code allows you to customize specific functions. To modify these files, you need proficiency in ADSP-21xxx assembly language and an understanding of the run-time environment, as explained in the section CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-3 DSP Run-Time Library Guide "C/C++ Run-Time Model and Environment" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors. Before modifying the source code, copy it to a file with a different filename and rename the function itself. Test the function before you use it in your system to verify that it is functionally correct. Devices supports the run-time library functions only as Analog provided. DSP Header Files The DSP header files contain prototypes for all the DSP library functions. When the appropriate #include preprocessor command is included in your source, the compiler uses the prototypes to check that each function is called with the correct arguments. Table 2-1 provides summaries of the DSP header files supplied with this release of the cc21k compiler. Table 2-1. Summaries of DSP Header Files 2-4 Header File Summary asm_sprt.h Mixed C/Assembly language macros cmatrix.h Arithmetic between complex matrices comm.h Scalar companders for A-law and -law complex.h Basic complex arithmetic functions cvector.h Arithmetic between complex vectors filter.h Filters and transformations filters.h Filters operating on scalar input values macros.h Macros to access processor features math.h Math functions matrix.h Matrix functions platform_include.h Platform-specific functions stats.h Statistical functions CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Table 2-1. Summaries of DSP Header Files (Cont'd) Header File Summary sysreg.h Functions for access to SHARC system registers trans.h Fast Fourier Transform functions (not optimized for SHARC SIMD architectures) vector.h Vector functions window.h Window generators The following sections describe the DSP header files in more detail. asm_sprt.h The asm_sprt.h header file consists of ADSP-21xxx assembly language macros, not C functions. They are used in your assembly routines that interface with C functions. For more information, see the section "Using Mixed C/C++ and Assembly Support Macros" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors. cmatrix.h The cmatrix.h header file contains prototypes for functions that perform basic arithmetic between two complex matrices, and also between a complex matrix and a complex scalar. The supported complex types are described under the header file complex.h. For a list of library functions that use this header, see Table 2-7. comm.h The comm.h header file includes the voice-band compression and expansion communication functions that operate on scalar input values. For a list of library functions that use this header, see Table 2-8. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-5 DSP Run-Time Library Guide companding functions that operate on vectors rather than Similar scalars are defined in the header file ; however, the funcfilter.h tions in comm.h and filter.h have different prototypes and therefore both header files cannot be included by the same source file. Any attempt to include both will result in the following error message being displayed: The include files comm.h and filter.h are mutually exclusive. Use filter.h for vectorized function arguments, or comm.h for scalar function arguments. complex.h The complex.h header file contains type definitions and basic arithmetic operations for variables of type complex_float, complex_double, and complex_long_double. The following structures are used to represent complex numbers in rectangular coordinates: typedef struct { float re; float im; } complex_float; typedef struct { double re; double im; } complex_double; typedef struct { long double re; long double im; } complex_long_double; 2-6 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Additional support for complex numbers is available via the cmatrix.h and cvector.h header files. For a list of library functions that use this header, see Table 2-9. cvector.h The cvector.h header file contains functions for basic arithmetic operations on vectors of type complex_float, complex_double, and complex_long_double. Support is provided for the dot product operation, as well as for adding, subtracting, and multiplying a vector by either a scalar or vector. For a list of library functions that use this header, see Table 2-10. filter.h The filter.h header file contains filters and other key signal processing transformations such as Fast Fourier Transform (FFTs) and convolution. The header file also includes the A-law and -law companders that are used by voice-band compression and expansion applications. The filters defined in this header file are finite and infinite impulse response filters, and multi-rate filters; all of these functions operate on an array of input samples. The header file defines three different sets of FFT functions. The first set comprises the functions cfftN, ifftN, and rfftN, where N stands for the number of points that the FFT function will compute (that is, 16, 32, 64, ...). These functions require the least amount of data memory space (by re-using the input array as temporary storage during execution) but at the expense of flexibility and performance. Each FFT function in this set is defined for a specific size of FFT; thus if an application calculated N different sizes of FFT, it would therefore include N different FFT library functions. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-7 DSP Run-Time Library Guide The second set of Fast Fourier Transforms comprises the functions cfft, ifft and rfft. The number of points these FFT functions will compute is passed as an argument. There is also a facility to supply a twiddle table (which is a set of sine and cosine coefficients required by the FFT function) and a facility to re-use twiddle tables generated for larger FFT sizes. In addition, by explicitly supplying temporary storage, the FFT functions can be used without overwriting the input data. Compared to the first set of functions, these functions require more data memory space, but performance and code size for multiple instances is improved. The third set of FFT functions that are defined by this header file represent a set of highly optimized functions. This set of functions, represented by cfftf, ifftf, and rfftf_2 sacrifice a level of flexibility in favor of optimal performance. For example, while they have an argument that specifies the size of the FFT, and an argument that is used to define the twiddle table, they do not have a twiddle table stride argument that allows the function to use a single table to generate different sized FFTs. Also these FFT functions overwrite the input data and the input arrays must be aligned on an address boundary that is a multiple of the FFT size. Memory usage lies between the first and second set of FFT functions. The header file also defines library functions that compute the magnitude of an FFT, and a function that convolves two arrays. header files , , and define functions The that may have the same name as functions defined by this header comm.h filters.h trans.h file. However, the functions defined by comm.h, filters.h and trans.h do not use the architecture's SIMD capabilities and they only operate on scalars. They also have different prototypes, and a source file therefore must not include filter.h and any of the header files comm.h, filters.h and trans.h. (An error message will be generated by the header file if this situation is detected.) For a list of library functions that use this header, see Table 2-11. 2-8 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library filters.h The filters.h header file includes a finite impulse response filter, an infinite impulse response filter, and a biquad function. These functions do not use the architecture's SIMD capabilities and only operate on scalars. For a list of library functions that use this header, see Table 2-11. set of filter functions is defined by the header file An alternative ; these functions use the same names and operate on vecfilter.h tors instead of scalars. However, they have different parameters and so a source file cannot include both header files; any attempt to include both will result in the following error message being displayed: These include files filters.h and filter.h are mutually exclusive. Use filter.h for vectorized function arguments, or filters.h for scalar function arguments. macros.h The macros.h header file contains a collection of macros and other definitions that allow some access to special computational features of the underlying hardware. Some portions of this file are present for compatibility with previous releases of the CCES toolset. In these cases, newer implementations provide equal or better access to the underlying functionality. math.h The standard math functions defined in the math.h header file have been augmented by implementations for the float and long double data types and additional functions that are Analog Devices extensions to the ANSI standard. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-9 DSP Run-Time Library Guide Table 2-2 provides a summary of the additional library functions defined by the math.h header file. Table 2-2. Math Library - Additional Functions Description Prototype Anti-log double alog (double x); float alogf (float x); long double alogd (long double x); Average double favg (double x, double y); float favgf (float x, float y); long double favgd (long double x, long double y); Base 10 anti-log double alog10 (double x); float alog10f (float x); long double alog10d (long double x); Clip double fclip (double x, double y); float fclipf (float x, float y); long double fclipd (long double x, long double y); Cotangent double cot (double x); float cotf (float x); long double cotd (long double x); Detect Infinity int isinf (double x); int isinff (float x); int isinfd (long double x); Detect NaN int isnan (double x); int isnanf (float x); int isnand (long double x); Maximum double fmax (double x, double y); float fmaxf (float x, float y); long double fmaxd (long double x, long double y); Minimum double fmin (double x, double y); float fminf (float x, float y); long double fmind (long double x, long double y); 2-10 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Table 2-2. Math Library - Additional Functions (Cont'd) Description Prototype Reciprocal of square root double rsqrt (double x); float rsqrtf (float x); long double rsqrtd (long double x); Sign copy double copysign (double x, double y); float copysignf (float x, float y); long double copysignd (long double x, long double y); For a list of library functions that use this header, see Table 2-12. matrix.h The matrix.h header file declares a number of function prototypes associated with basic arithmetic operations on matrices of type float, double, and long double. The header file contains support for arithmetic between two matrices, and between a matrix and a scalar. For a list of library functions that use this header, see Table 2-13. platform_include.h The platform_include.h header file includes the appropriate header files that define symbolic names for processor-specific system register bits. These header files also contain symbolic definitions for the IOP register address memory and IOP control/status register bits. platform_include.h causes one or two include files to be included, depending on whether assembly or C/C++ code is being processed. For more information on the platform-specific include files, see the following sections: * Header Files That Define Processor-Specific System Register Bits * Header Files That Allow Access to Memory-Mapped Registers From C/C++ Code CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-11 DSP Run-Time Library Guide Header Files That Define Processor-Specific System Register Bits The following header files define symbolic names for processor-specific system register bits. They also contain symbolic definitions for the IOP register address memory and IOP control/status register bits. Table 2-3 provides the header file names for processor-specific register bits. Table 2-3. Header Files for Processor-Specific Register Bits Header File Processor def21160.h ADSP-21160 bit definitions def21161.h ADSP-21161 bit definitions def21261.h ADSP-21261 bit definitions def21262.h ADSP-21262 bit definitions def21266.h ADSP-21266 bit definitions def21362.h ADSP-21362 bit definitions def21363.h ADSP-21363 bit definitions def21364.h ADSP-21364 bit definitions def21365.h ADSP-21365 bit definitions def21366.h ADSP-21366 bit definitions def21367.h ADSP-21367 bit definitions def21368.h ADSP-21368 bit definitions def21369.h ADSP-21369 bit definitions def21371.h ADSP-21371 bit definitions def21375.h ADSP-21375 bit definitions def21467.h ADSP-21467 bit definitions def21469.h ADSP-21469 bit definitions def21477.h ADSP-21477 bit definitions def21478.h ADSP-21478 bit definitions def21479.h ADSP-21479 bit definitions def21483.h ADSP-21483 bit definitions 2-12 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Table 2-3. Header Files for Processor-Specific Register Bits (Cont'd) Header File Processor def21486.h ADSP-21486 bit definitions def21487.h ADSP-21487 bit definitions def21488.h ADSP-21488 bit definitions def21489.h ADSP-21489 bit definitions Header Files That Allow Access to Memory-Mapped Registers From C/C++ Code In order to allow safe access to memory-mapped registers from C/C++ code, the header files listed below are supplied. Each memory-mapped register's name is prefixed with "p" and is cast appropriately to ensure that the code is generated correctly. For example, SYSCON is defined as follows: #define pSYSCON ((volatile unsigned int *) 0x00) and can be used as: *pSYSCON |= 0x6000; this method of accessing memory-mapped registers in prefer Use ence to using statements. asm Supplied header files are: Cdef21160.h Cdef21161.h Cdef21261.h Cdef21262.h Cdef21266.h Cdef21362.h Cdef21363.h Cdef21364.h Cdef21365.h Cdef21366.h Cdef21367.h Cdef21368.h Cdef21369.h Cdef21371.h Cdef21375.h Cdef21467.h Cdef21469.h Cdef21477.h Cdef21478.h Cdef21479.h Cdef21483.h Cdef21486.h Cdef21487.h Cdef21488.h Cdef21489.h CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-13 DSP Run-Time Library Guide stats.h The stats.h header file includes various statistics functions of the DSP library, such as mean() and autocorr(). For a list of library functions that use this header, see Table 2-14. sysreg.h The sysreg.h header file defines a set of built-in functions that provide efficient access to the SHARC system registers from C. The supported functions are fully described in the section "Access to System Registers" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors. trans.h The trans.h header file defines a set of Fast Fourier Transform (FFT) functions that operate on data in which the real and imaginary parts of both the input and output signal are stored in separate vectors. The functions that are defined by the header file include a set of functions that compute a complex FFT, the inverse of a complex FFT, and a set of functions that compute an FFT using real data only (this is equivalent to computing an FFT whose imaginary input component is set to zero). Each function in this header file uses a built-in twiddle table and is designed to handle a specific size of FFT. For example, the function cfft32 computes a complex FFT with 32 data points, ifft64 computes the inverse of a complex FFT that has 64 data points, and rfft128 computes a real FFT with 128 data points. The sizes of FFT supported are 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768 and 65536. For a list of library functions that use this header, see Table 2-15. of the functions defined here use the SHARC SIMD capabil None ity. However, an alternative set of functions with the same names are defined in the header file filter.h, but these functions have different parameters and their prototypes are incompatible. For 2-14 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library this reason, a source file cannot include both these header files, and any attempt to do so will result in the following error message being displayed: The include files trans.h and filter.h are mutually exclusive. Use for function arguments of type complex_float, or trans.h otherwise. filter.h vector.h The vector.h header file contains functions for operating on vectors of type float, double, and long double. Support is provided for the dot product operation as well as for adding, subtracting, and multiplying a vector by either a scalar or vector. Similar support for the complex data types is defined in the header file cvector.h. For a list of library functions that use this header, see Table 2-16. window.h The window.h header file contains various functions to generate windows based on various methodologies. The functions, defined in the window.h header file, are listed in Table 2-4. For all window functions, a stride parameter a can be used to space the window values. The window length parameter n equates to the number of elements in the window. Therefore, for a stride a of 2 and a length n of 10, an array of length 20 is required, where every second entry is untouched. Table 2-4. Window Generator Functions Description Prototype Generate Bartlett window void gen_bartlett (float w[], int a, int n) Generate Blackman window void gen_blackman (float w[], int a, int n) CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-15 DSP Run-Time Library Guide Table 2-4. Window Generator Functions (Cont'd) Description Prototype Generate Gaussian window void gen_gaussian (float w[], float alpha, int a, int n) Generate Hamming window void gen_hamming (float w[], int a, int n) Generate Hanning window void gen_hanning (float w[], int a, int n) Generate Harris window void gen_harris (float w[], int a, int n) Generate Kaiser window void gen_kaiser (float w[], float beta, int a, int n) Generate rectangular window void gen_rectangular (float w[], int a, int n) Generate triangle window void gen_triangle (float w[], int a, int n) Generate von Hann window void gen_vonhann (float w[], int a, int n) For a list of library functions that use this header, see Table 2-17. Built-In DSP Library Functions The C/C++ compiler supports built-in functions (also known as intrinsic functions) that enable efficient use of hardware resources. Knowledge of these functions is built into the compiler. Your program uses them via normal function call syntax. The compiler notices the invocation and replaces a call to a DSP library function with one or more machine instructions, just as it does for normal operators like "+" and "*". Built-in functions are declared in the builtins.h header file and have names which begin with double underscores, __builtin. 2-16 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Identifiers beginning with " " are reserved by the C standard, so these names do not conflict with user-defined identifiers. __ The built-in DSP library functions supported by the cc21k compiler are listed in Table 2-5. Refer to Using Compiler Built-In C Library Functions for more information on this topic. Table 2-5. Built-in DSP Functions avg clip copysign copysignf favg favgf fmax fmaxf fmin fminf labs lavg lclip lmax lmin max min , Functions built-in function only if copysign favg, fmax, double and fmin are compiled as a is the same size as float. If you want to use the C run-time library functions of the same name instead of the built-in function, refer to "builtins.h" in the C/C++ Compiler Manual for SHARC Processors. Implications of Using SIMD Mode All SHARC processors supported by CCES can perform SIMD (Single-Instruction, Multiple-Data) operations which can double the computational rate over the normal SISD (Single-Instruction, Single-Data) operations; the increase in performance occurs because memory accesses and computations are performed in pairs using the architecture's second processing element. Chapter 1 of the C/C++ Compiler Manual for SHARC Processors has a section called "A Brief Introduction to SIMD Mode", which explains the mode in more detail. The DSP run-time library makes extensive use of the processors' SIMD capabilities. However different SHARC processors have different CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-17 DSP Run-Time Library Guide constraints regarding memory access in SIMD mode and you should refer to the appropriate hardware reference manual regarding the restrictions that apply to your processor. As an example, SIMD memory accesses using the ADSP-2116x family of processors should be double-word aligned, and for some processors SIMD access to external memory is not supported (see Using Data in External Memory for more information on this topic). Because of these restrictions, it is important to ensure that all vectors and arrays that are passed as arguments to the DSP library functions can be accessed safely in SIMD mode. Alternative versions of the DSP run-time library functions will be linked into an application if the corresponding C source that calls the DSP library function is compiled with the switch -no-simd; the alternative versions that will be included in an application will use normal SISD operations and not the processor's SIMD mode. (Refer to the section "SIMD Support" in the C/C++ Compiler Manual for SHARC Processors for more information about how the compiler uses the SIMD feature.) Some DSP library functions do not use SIMD due to the nature of their algorithm and so are not affected by any constraints associated with the feature. These library functions include all long double functions and the window generators. Other functions that do not use SIMD mode are listed in Table 2-6. Table 2-6. Functions Not Using the SIMD Feature biquad cmatmmlt cmatsmlt convolve cvecdot cvecsmlt fir_decima fir_interp iir histogram matmmlt matinv transpm zero_cross 2-18 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Using Data in External Memory The run-time functions described in this manual have been optimized to exploit the features of the SHARC architecture. This can lead to restrictions in the placement of data in external memory, particularly on some ADSP-211xx, ADSP-212xx and ADSP-213xx processors. The ADSP-212xx and some ADSP-2136x processors do not support direct memory accesses to external memory. This means that the run-time functions cannot read or write to data in external memory. Any such data must first be brought into internal memory. The library functions read_extmem and write_extmem may be used to transfer data between internal memory and external memory. Some ADSP-211xx and ADSP-213xx processors have a 32-bit external bus and, due to the shorter bus width, are unable to support SIMD access to external memory. For this reason, the DSP library contains an alternative set of functions that do not use the architecture's SIMD capabilities. This alternative set is selected in preference to the standard library functions if the -no-simd compiler switch is specified at compilation time. The ADSP-214xx processors do support SIMD access to external memory, but not long word (LW) access to external memory. Therefore the cvecvmltf library function is not suitable for use with data placed in external memory, since it makes use of the LW mnemonic. (This also applies to the cvecvmlt function if doubles are the same size as floats.) An alternative version of the function does not use the architecture's SIMD capabilities and is suitable for use with data placed in external memory. This version is available by way of the -no-simd compiler switch. The optimized FFT functions cfftf, ifftf, and rfftf_2 use SIMD and long word memory accesses to improve their performance. All data passed to these functions must be allocated in internal memory. There are no versions of these functions that support data in external memory. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-19 Documented Library Functions Documented Library Functions The C run-time library has several categories of functions and macros defined by the ANSI C standard, plus extensions provided by Analog Devices. The following tables list the library functions documented in this chapter. Note that the tables list the functions for each header file separately; however, the reference pages for these library functions present the functions in alphabetical order. Table 2-7 lists the library functions in the cmatrix.h header file. Refer to cmatrix.h for more information on this header file. Table 2-7. Library Functions in cmatrix.h cmatmadd cmatmmlt cmatmsub cmatsadd cmatsmlt cmatssub Table 2-8 lists the library functions in the comm.h header file. Refer to comm.h for more information on this header file. Table 2-8. Library Functions in comm.h a_compress a_expand mu_compress mu_expand 2-20 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Table 2-9 lists the library functions in the complex.h header file. Refer to complex.h for more information on this header file. Table 2-9. Supported Library Functions in complex.h arg cabs cadd cartesian cdiv cexp cmlt conj csub norm polar Table 2-10 lists the library functions in the cvector.h header file. Refer to cvector.h for more information on this header file. Table 2-10. Supported Library Functions in cvector.h cvecdot cvecsadd cvecsmlt cvecssub cvecvadd cvecvmlt cvecvsub Table 2-11 lists the library functions in the filter.h header file. Refer to filter.h for more information on this header file. Table 2-11. Supported Library Functions in filter.h a_compress a_expand biquad cfft cfft_mag cfftN cfftf convolve fft_magnitude fftf_magnitude fir fir_decima fir_interp firf ifft ifftf ifftN iir mu_compress mu_expand rfft CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-21 Documented Library Functions Table 2-11. Supported Library Functions in filter.h (Cont'd) rfft_mag rfftf_2 twidfft twidfftf rfftN Table 2-12 lists the library functions in the math.h header file. Refer to math.h for more information on this header file. Table 2-12. Supported Library Functions in math.h alog alog10 copysign cot favg fclip fmax fmin rsqrt Table 2-13 lists the library functions in the matrix.h header file. Refer to matrix.h for more information on this header file. Table 2-13. Supported Library Functions in matrix.h matinv matmadd matmmlt matmsub matsadd matsmlt matssub transpm Table 2-14 lists the library functions in the stats.h header file. Refer to stats.h for more information on this header file. Table 2-14. Supported Library Functions in stats.h autocoh autocorr crosscoh crosscorr histogram mean rms var zero_cross 2-22 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Table 2-15 lists the library functions in the trans.h header file. Refer to trans.h for more information on this header file. Table 2-15. Supported Library Functions in trans.h cfftN ifftN rfftN Table 2-16 lists the library functions in the vector.h header file. Refer to vector.h for more information on this header file. Table 2-16. Supported Library Functions in vector.h vecdot vecsadd vecsmlt vecssub vecvadd vecvmlt vecvsub Table 2-17 lists the library functions in the window.h header file. Refer to window.h for more information on this header file. Table 2-17. Supported Library Functions in window.h gen_bartlett gen_blackman gen_gaussian gen_hamming gen_hanning gen_harris gen_kaiser gen_rectangular gen_triangle gen_vonhann CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-23 Documented Library Functions DSP Run-Time Library Reference The DSP run-time library is a collection of functions that you can call from your C/C++ programs. Notation Conventions An interval of numbers is indicated by the minimum and maximum, separated by a comma, and enclosed in two square brackets, two parentheses, or one of each. A square bracket indicates that the endpoint is included in the set of numbers; a parenthesis indicates that the endpoint is not included. Restrictions When polymorphic functions are used and the function returns a pointer to Program Memory, cast the output of the function to pm. For example, (char pm *). Reference Format Each function in the library has a reference page. These pages have the following format: Name and purpose of the function Synopsis - Required header file and functional prototype Description - Function specification Algorithm - High-level mathematical representation of the function Error Conditions - Method that the functions use to indicate an error Example - Typical function usage See Also - Related functions 2-24 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library a_compress A-law compression Synopsis (Scalar-Valued Version) #include int a_compress (int x); Synopsis (Vector-Valued Version) #include int *a_compress (const int dm input[], int dm output[], int length); Description The A-law compression functions take a linear 13-bit signed speech sample and compresses it according to ITU recommendation G.711. The scalar-valued version of a_compress inputs a single data sample and returns an 8-bit compressed output sample. The vector-valued version of a_compress takes the array input, and returns the compressed 8-bit samples in the vector output. The parameter length defines the size of both the input and output vectors. The function returns a pointer to the output array. The vector-valued version of uses serial port 0 to per form the companding on an ADSP-21160 processor; serial port 0 a_compress therefore must not be in use when this routine is called. The serial port is not used by this function on any other ADSP-21xxx SIMD architectures. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-25 Documented Library Functions Error Conditions None. Example Scalar-Valued #include int sample, compress; compress = a_compress (sample); Vector-Valued #include #define NSAMPLES 50 int data[NSAMPLES], compressed[NSAMPLES]; a_compress (data, compressed, NSAMPLES); See Also a_expand, mu_compress 2-26 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library a_expand A-law expansion Synopsis (Scalar-Valued Version) #include int a_expand (int x); Synopsis (Vector-Valued Version) #include int *a_expand (const int dm input[], int dm output[], int length); Description The a_expand function takes an 8-bit compressed speech sample and expands it according to ITU recommendation G.711 (A-law definition). The scalar version of a_expand inputs a single data sample and returns a linear 13-bit signed sample. The vector version of the a_expand function takes an array of 8-bit compressed speech samples and expands them according to ITU recommendation G.711 (A-law definition). The array returned contains linear 13-bit signed samples. This function returns a pointer to the output data array. vector version of the a_expand function uses serial port 0 to The perform the companding on an ADSP-21160 processor; serial port 0 therefore must not be in use when this routine is called. The serial port is not used by this function on any other ADSP-21xxx SIMD architectures. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-27 Documented Library Functions Error Conditions None. Example Scalar-Valued #include int compressed_sample, expanded; expanded = a_expand (compressed_sample); Vector-Valued #include #define NSAMPLES 50 int compressed_data[NSAMPLES]; int expanded_data[NSAMPLES]; a_expand (compressed_data, expanded_data, NSAMPLES); See Also a_compress, mu_expand 2-28 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library alog Anti-log Synopsis #include float alogf (float x); double alog (double x); long double alogd (long double x); Description The anti-log functions calculate the natural (base e) anti-log of their argument. An anti-log function performs the reverse of a log function and is therefore equivalent to exponentiation. Error Conditions The input argument x for alogf must be in the domain [-87.3, 88.7] and the input argument for alogd must be in the domain [-708.2, 709.1]. The functions return HUGE_VAL if x is greater than the domain, and return 0.0 if x is less than the domain. Example #include double x = 1.0; double y; y = alog(x); /* y = 2.71828... */ See Also alog10, exp, log, pow CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-29 Documented Library Functions alog10 Base 10 anti-log Synopsis #include float alog10f (float x); double alog10 (double x); long double alog10d (long double x); Description The alog10 functions calculate the base 10 anti-log of their argument. An anti-log function performs the reverse of a log function and is therefore equivalent to exponentiation. Therefore, alog10(x) is equivalent to exp(x * log(10.0)). Error Conditions The input argument x for alog10f must be in the domain [-37.9, 38.5], and the input argument for alog10d must be in the domain [-307.57, 308.23]. The functions return HUGE_VAL if x is greater than the domain, and they return 0.0 if x is less than the domain. Example #include double x = 1.0; double y; y = alog10(x); /* y = 10.0 */ See Also alog, exp, log10, pow 2-30 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library arg Get phase of a complex number Synopsis #include float argf (complex_float a); double arg (complex_double a); long double argd (complex_long_double a); Description The arg functions compute the phase associated with a Cartesian number represented by the complex argument a, and return the result. Algorithm The phase of a Cartesian number is computed as: Im(a) c = atan ------------ Re(a) Error Conditions The arg function return a zero if a.re <> 0 and a.im = 0. Example #include complex_float x = {0.0,1.0}; float r; r = argf(x); /* r = pi/2 */ CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-31 Documented Library Functions See Also atan2, cartesian, polar 2-32 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library autocoh Auto-coherence Synopsis #include float *autocohf (float output[], const float input[], int samples, int lags); double *autocoh (double output[], const double input[], int samples, int lags); long double *autocohd (long double output[], const long double input[], int samples, int lags); Description The autocoh functions compute the auto-coherence of the signal contained in the array input of length samples. The auto-coherence of an input signal is its auto-correlation minus the product of the partial means of the input signal. The auto-coherence between the input signal and itself is returned in the array output of length lags. The functions return a pointer to the output array. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-33 Documented Library Functions Error Conditions The autocoh functions will return without modifying the output array if either the number of samples is less than or equal to 1, or if the number of lags is less than 1, or if the number of lags is not less than the number of samples. Algorithm The auto-coherence functions are based on the following algorithm. 1c k = ---------n-k 1 a j a j + k - ----------n-k n-k-1 j=0 n-1 1 a j ----------- a j n-k j=k n-k-1 j=0 where: n = samples k = 0 to lags-1 a = input Example #include #define SAMPLES 1024 #define LAGS 16 float x[SAMPLES]; float response[LAGS]; autocohf (response, x, SAMPLES, LAGS); See Also autocorr, crosscoh, crosscorr 2-34 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library autocorr Autocorrelation Synopsis #include float *autocorrf (float dm out[], const float dm in[], int samples, int lags); double *autocorr (double dm out[], const double dm in[], int samples, int lags); long double *autocorrd (long double dm out[], const long double dm in[], int samples, int lags); Description The autocorrelation functions perform an autocorrelation of a signal. Autocorrelation is the cross-correlation of a signal with a copy of itself. It provides information about the time variation of the signal. The signal to be autocorrelated is given by the in[] input array. The number of samples of the autocorrelation sequence to be produced is given by lags. The length of the input sequence is given by samples. The functions return a pointer to the out[] output data array of length lags. Autocorrelation is used in digital signal processing applications such as speech analysis. autocorrf function (and , if are the same size The as ) uses SIMD by default. Refer to Implications of Using autocorr doubles floats SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-35 Documented Library Functions Algorithm The following equation is the basis of the algorithm. 1 c k = --- n a j a j + k n-k-1 j=0 where: a = in; k = {0, 1, ..., m-1} m is the number of lags n is the size of the input vector in Error Conditions None. Example #include #define SAMPLES 1024 #define LAGS 16 double excitation[SAMPLES]; double response[LAGS]; int lags = LAGS; autocorr (response, excitation, SAMPLES, lags); See Also autocoh, crosscoh, crosscorr 2-36 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library biquad Biquad filter section Synopsis (Scalar-Valued Version) #include float biquad (float sample, const float pm coeffs[], float dm state[], int sections); Synopsis (Vector-Valued Version) #include float *biquad (const float dm input[], float dm output[], const float pm coeffs[], float dm state[], int samples, int sections); Description The biquad functions implement a cascaded biquad filter defined by the coefficients and the number of sections that are supplied in the call to the function. The scalar version of biquad produces the filtered response of its input data sample which it returns as the result of the function. The vector versions of the biquad function generate the filtered response of the input data input and store the result in the output vector output. The number of input samples and the length of the output vector is specified by the argument samples. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-37 Documented Library Functions The number of biquad sections is specified by the parameter sections, and each biquad section is represented by five coefficients A1, A2, B0, B1, and B2. The biquad functions assume that the value of A0 is 1.0, and A1 and A2 should be scaled accordingly. These coefficients are passed to the biquad functions in the array coeffs which must be located in Program Memory (PM). The definition of the coeffs array is: float pm coeffs[5*sections]; For the scalar version of biquad the five coefficients of each section must be stored in reverse order: B2, B1, B0, A2, A1 For the vector versions of the biquad function, the five coefficients must be stored in the order: A2, A1, B2, B1, B0 Each filter should have its own delay line, which is represented by the array state. The state array should be large enough for two delay elements per biquad section and hold an internal pointer that allows the filter to be restarted. The definition of the state is: float dm state[2*sections + 1]; The state array should be initially cleared to zero before calling the function for the first time, and should not otherwise be modified by the user program. library function uses the architecture's dual-data move instruc The tion to provide simultaneous access to the filter coefficients (in PM data memory) and the delay line. When running on an ADSP-21367, ADSP-21368 or ADSP-21369 processor, the filter coefficients and the delay line must not both be allocated in external memory; otherwise, the function can generate an incorrect set of results. This occurs because in a dual-data move instruction, the hardware does not support both memory accesses allocated to 2-38 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library external memory. Therefore, ensure that the filter coefficients or the delay line (or, optionally, both) are allocated in internal memory when running on one of the ADSP-2136x processors specified above. The vector version of the biquad functions return a pointer to the output vector; the scalar version of the function returns the filtered response of its input sample. Algorithm The following equations are the basis of the algorithm. -1 -2 B0 + B1 z + B2 z H z = ---------------------------------------------1 -2 1 - A1 z - A2 z where Dm = A2 Dm - 2 + A1 Dm - 1 + xm Ym = B2 Dm - 2 + B1 Dm - 1 + B0 Dm where: m = {0,1,2,...,samples-1} The algorithm used is adapted from Digital Signal Processing, Oppenheim and Schafer, New Jersey, Prentice Hall, 1975. For more information, see Figure 2-1. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-39 Documented Library Functions Error Conditions None. Example Scalar-Valued #include #define NSECTIONS #define NSTATE 4 ((2*NSECTIONS) + 1) float sample, response, state[NSTATE]; float pm coeffs[5*NSECTIONS]; int i; for (i = 0; i < NSTATE; i++) state[i] = 0; /* initialize state array */ response = biquad (sample, coeffs, state, NSECTIONS); Vector-Valued #include #define NSECTIONS 4 #define NSAMPLES 64 #define NSTATE ((2*NSECTIONS) + 1) float input[NSAMPLES]; float output[NSAMPLES]; float state[NSTATE]; float pm coeffs[5*NSECTIONS]; int i; 2-40 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library for (i = 0; i < NSTATE; i++) state[i] = 0; /* initialize state array */ biquad (input, output, coeffs, state, NSAMPLES, NSECTIONS); Note that N = the number of biquad sections. Figure 2-1. Biquad Sections See Also fir, iir CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-41 Documented Library Functions cabs Complex absolute value Synopsis #include float cabsf (complex_float z); double cabs (complex_double z); long double cabsd (complex_long_double z); Description The cabs functions return the floating-point absolute value of their complex input. The absolute value of a complex number is evaluated with the following formula. y = 2 2 Re z + Im z Error Conditions None. Example #include complex_float cnum; float answer; 2-42 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cnum.re = 12.0; cnum.im = 5.0; answer = cabsf (cnum); /* answer = 13.0 */ See Also fabs, llabs CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-43 Documented Library Functions cadd Complex addition Synopsis #include complex_float caddf (complex_float a, complex_float b); complex_double cadd (complex_double a, complex_double b); complex_long_double caddd (complex_long_double a, complex_long_double b); Description The cadd functions add the two complex values a and b together, and return the result. Error Conditions None. Example #include complex_double x = {9.0,16.0}; complex_double y = {1.0,-1.0}; complex_double z; z = cadd (x,y); /* z.re = 10.0, z.im = 15.0 */ See Also cdiv, cmlt, csub 2-44 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cartesian Convert Cartesian to polar notation Synopsis #include float cartesianf (complex_float a, float *phase); double cartesian (complex_double a, double *phase); long double cartesiand (complex_long_double a, long double *phase); Description The cartesian functions transform a complex number from Cartesian notation to polar notation. The Cartesian number is represented by the argument a that the function converts into a corresponding magnitude, which it returns as the function's result, and a phase that is returned via the second argument phase. The formula for converting from Cartesian to polar notation is given by: magnitude = cabs(a) phase = arg(a) Error Conditions The cartesian functions return a zero for the phase if a.re <> 0 and a.im = 0. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-45 Documented Library Functions Example #include complex_float point = {-2.0, 0.0}; float phase; float mag; mag = cartesianf (point,&phase); /* mag = 2.0, phase = */ See Also arg, cabs, polar 2-46 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cdiv Complex division Synopsis #include complex_float cdivf (complex_float a, complex_float b); complex_double cdiv (complex_double a, complex_double b); complex_long_double cdivd (complex_long_double a, complex_long_double b); Description The cdiv functions compute the complex division of complex input a by complex input b, and return the result. Algorithm The following equation is the basis of the algorithm. Re a Re b + Im a Im b Re c = -------------------------------------------------------------------------2 2 Re b + Im b Re b Im a - Im b Re a Im c = ------------------------------------------------------------------------2 2 Re b + Im b Error Conditions The cdiv functions set both the real and imaginary parts of the result to Infinity if b is equal to (0.0,0.0). CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-47 Documented Library Functions Example #include complex_double x = {3.0,11.0}; complex_double y = {1.0, 2.0}; complex_double z; z = cdiv (x,y); /* z.re = 5.0, z.im = 1.0 */ See Also cadd, cmlt, csub 2-48 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cexp Complex exponential Synopsis #include complex_float cexpf (complex_float z); complex_double cexp (complex_double z); complex_long_double cexpd (complex_long_double z); Description The cexp functions compute the exponential value e to the power of the real argument z in the complex domain. The exponential of a complex value is evaluated with the following formula. Re(y) = exp (Re(z)) * cos (Im(z)); Im(y) = exp (Re(z)) * sin (Im(z)); Error Conditions For underflow errors, the cexp functions return zero. Example #include complex_float cnum; complex_float answer; cnum.re = 1.0; cnum.im = 0.0; answer = cexpf (cnum); /* answer = (2.7182 + 0i) */ CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-49 Documented Library Functions See Also log, pow 2-50 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cfft Complex radix-2 Fast Fourier Transform Synopsis #include complex_float *cfft (complex_float complex_float dm input[], dm temp[], complex_float dm output[], const complex_float pm twiddle[], int twiddle_stride, int n); Description The cfft function transforms the time domain complex input signal sequence to the frequency domain by using the radix-2 Fast Fourier Transform (FFT). The size of the input array input, the output array output, and the temporary working buffer temp must be at least n, where n represents the number of points in the FFT; n must be a power of 2 and no smaller than 8. If the input data can be overwritten, memory can be saved by setting the pointer of the temporary array explicitly to the input array, or to NULL. (In either case the input array will also be used as the temporary working array.) The minimum size of the twiddle table must be n/2. A larger twiddle table may be used, provided that the value of the twiddle table stride argument twiddle_stride is set appropriately. If the size of the twiddle table is x, then twiddle_stride must be set to (2*x)/n. If a larger twiddle table is being used, the twiddle stride must be adjusted to be equal to the fft size of the table generated divided by the fft size of the table being used. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-51 Documented Library Functions The library function twidfft (on page 2-220) can be used to compute the required twiddle table. The coefficients generated are positive cosine coefficients for the real part and negative sine coefficients for the imaginary part. library also contains the cfftf function (on page 2-63), which is anTheoptimized implementation of a complex FFT using a fast radix-2 algorithm. The cfftf function however imposes certain memory alignment requirements that may not be appropriate for some applications. The function returns the address of the output array. cfft function uses SIMD by default. Refer to Implications of The Using SIMD Mode for more information. Algorithm The following equation is the basis of the algorithm. N-1 Xk = nk x n W N n=0 Error Conditions None. 2-52 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define N_FFT 64 complex_float input[N_FFT]; complex_float output[N_FFT]; complex_float temp[N_FFT]; int twiddle_stride = 1; complex_float pm twiddle[N_FFT/2]; /* Populate twiddle table */ twidfft(twiddle, N_FFT); /* Compute Fast Fourier Transform */ cfft(input, temp, output, twiddle, twiddle_stride, N_FFT); See Also cfftf, cfftN, fft_magnitude, ifft, rfft, twidfft CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-53 Documented Library Functions cfft_mag cfft magnitude Synopsis #include float *cfft_mag (complex_float dm input[], float dm output[], int fftsize); Description The cfft_mag function computes a normalized power spectrum from the output signal generated by a cfft or cfftN function. The size of the signal and the size of the power spectrum is fftsize. The function returns a pointer to the output matrix. The Nyquist frequency is located at (fftsize/2) + 1. Algorithm The algorithm used to calculate the normalized power spectrum is: 2 2 Re a z + Im a z magnitude z = -----------------------------------------------------------fftsize where: z = {0, 1, ..., fftsize-1} a is the input vector input 2-54 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Error Conditions None. Example #include #define N 64 complex_float fft_input[N]; complex_float fft_output[N]; float spectrum[N]; cfft64 (fft_input, fft_output); cfft_mag (fft_output, spectrum, N); See Also cfft, cfftN, fft_magnitude, fftf_magnitude, rfft_mag this function uses SIMD. Refer to Implications of ByUsingdefault, SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-55 Documented Library Functions cfftN N-point complex radix-2 Fast Fourier Transform Synopsis #include float *cfft65536 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *cfft32768 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *cfft16384 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *cfft8192 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *cfft4096 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *cfft2048 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *cfft1024 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); 2-56 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library float *cfft512 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *cfft256 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *cfft128 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *cfft64 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *cfft32 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *cfft16 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *cfft8 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); Description Each of these cfftN functions computes the N-point radix-2 Fast Fourier Transform (CFFT) of its floating-point input (where N is 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768 or 65536). CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-57 Documented Library Functions There are fourteen distinct functions in this set. All perform the same function with the same type and number of arguments. The only difference between them is the size of the arrays on which they operate. Call a particular function by substituting the number of points for N, as in cfft8 (r_inp, i_inp, r_outp, i_outp); The input to cfftN are two floating-point arrays of N points. The array real_input contains the real components of the complex signal, and the array imag_input contains the imaginary components. If there are fewer than N actual data points, you must pad the arrays with zeros to make N samples. However, better results occur with less zero padding. The input data should be windowed (if necessary) before calling the function, because no preprocessing is performed on the data. If the input data can be overwritten, then the cfftN functions allow the array real_input to share the same memory as the array real_output, and imag_input to share the same memory as imag_output. This improves memory usage, but at the cost of run-time performance. The cfftN functions return a pointer to the real_output array. cfftN library functions have not been optimized for SHARC The SIMD processors. Alternative FFT functions that do exploit this feature are defined in the filter.h header file. Error Conditions None. 2-58 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define N 2048 float real_input[N], imag_input[N]; float real_output[N], imag_output[N]; cfft2048 (real_input, imag_input, real_output, imag_output); See Also cfft, cfftN, fft_magnitude, ifftN, rfftN CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-59 Documented Library Functions cfftN N-point complex input FFT Synopsis #include complex_float *cfft65536 (complex_float dm input[], complex_float dm output[]); complex_float *cfft32768 (complex_float dm input[], complex_float dm output[]); complex_float *cfft16384 (complex_float dm input[], complex_float dm output[]); complex_float *cfft8192 (complex_float dm input[], complex_float dm output[]); complex_float *cfft4096 (complex_float dm input[], complex_float dm output[]); complex_float *cfft2048 (complex_float dm input[], complex_float dm output[]); complex_float *cfft1024 (complex_float dm input[], complex_float dm output[]); complex_float *cfft512 (complex_float dm input[], complex_float dm output[]); complex_float *cfft256 (complex_float dm input[], complex_float dm output[]); 2-60 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library complex_float *cfft128 (complex_float dm input[], complex_float dm output[]); complex_float *cfft64 (complex_float dm input[], complex_float dm output[]); complex_float *cfft32 (complex_float dm input[], complex_float dm output[]); complex_float *cfft16 (complex_float dm input[], complex_float dm output[]); complex_float *cfft8 (complex_float dm input[], complex_float dm output[]); Description These cfftN functions are defined in the header file filter.h. They have been optimized to take advantage of the SIMD capabilities of the SHARC processors supported by CCES. These FFT functions require complex arguments to ensure that the real and imaginary parts are interleaved in memory and thus are accessible in a single cycle using the wider data bus of the processor. Each of these cfftN functions computes the N-point radix-2 Fast Fourier Transform (CFFT) of its complex input (where N is 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, or 65536). There are fourteen distinct functions in this set. All perform the same function with the same type and number of arguments. The only difference between them is the size of the arrays on which they operate. Call a particular function by substituting the number of points for N, as in cfft8 (input, output); The input to cfftN is a floating-point array of N points. If there are fewer than N actual data points, you must pad the array with zeros to make N CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-61 Documented Library Functions samples. Better results occur with less zero padding, however. The input data should be windowed (if necessary) before calling the function because no preprocessing is performed on the data. Optimal memory usage can be achieved by specifying the input array as the output array, but at the cost of run-time performance. The cfftN() function returns a pointer to the output array. cfftN functions use the input array as an intermediate work The space. If the input data is to be preserved it must first be copied to a safe location before calling these functions. Error Conditions None. Example #include #define N 2048 complex_float input[N], output[N]; cfft2048 (input, output); See Also cfft, cfftf, fft_magnitude, ifftN, rfftN default these functions use SIMD. For more information, refer Byto Implications of Using SIMD Mode. 2-62 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cfftf fast N-point complex radix-2 Fast Fourier Transform Synopsis #include void cfftf (float data_real[], float data_imag[], float temp_real[], float temp_imag[], const float twid_real[], const float twid_imag[], int n); Description The cfftf function transforms the time domain complex input signal sequence to the frequency domain by using the accelerated version of the Discrete Fourier Transform known as a Fast Fourier Transform or FFT. It decimates in frequency using an optimized radix-2 algorithm. The array data_real contains the real part of a complex input signal, and the array data_imag contains the imaginary part of the signal. On output, the function overwrites the data in these arrays and stores the real part of the FFT in data_real, and the imaginary part of the FFT in data_imag. If the input data is to be preserved, it must first be copied to a safe location before calling this function. The argument n represents the number of points in the FFT; it must be a power of 2 and must be at least 64. The cfftf function has been designed for optimal performance and requires that the arrays data_real and data_imag are aligned on an address boundary that is a multiple of the FFT size. For certain applications, this alignment constraint may not be appropriate; in such cases, the application should call the cfft function instead with no loss of facility (apart from performance). CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-63 Documented Library Functions The arrays temp_real and temp_imag are used as intermediate temporary buffers and should each be of size n. The twiddle table is passed in using the arrays twid_real and twid_imag. The array twid_real contains the positive cosine factors, and the array twid_imag contains the negative sine factors; each array should be of size n/2 . The twidfftf function (on page 2-223) may be used to initialize the twiddle table arrays. It is recommended that the arrays containing real parts (data_real, temp_real, and twid_real) are allocated in separate memory blocks from the arrays containing imaginary parts (data_imag, temp_imag, and twid_imag); otherwise, the performance of the function degrades. cfftf function has been implemented to make highly efficient The use of the processor's SIMD capabilities and long word addressing mode. The function therefore imposes the following restrictions: * All the arrays that are passed to the function must be allocated in internal memory. The DSP run-time library does not contain a version of the function that can be used with data in external memory. * The function should not be used with any application that relies on the -reserve register[, register...] switch. * Due to the alignment restrictions of the input arrays (as documented above), it is unlikely that the function will generate the correct results if the input arrays are allocated on the stack. For more information, refer to refer to Implications of Using SIMD Mode and Using Data in External Memory. Error Conditions None. 2-64 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define FFT_SIZE 1024 #pragma align 1024 static float dm input_r[FFT_SIZE]; #pragma align 1024 static float pm input_i[FFT_SIZE]; float dm temp_r[FFT_SIZE]; float pm temp_i[FFT_SIZE]; float dm twid_r[FFT_SIZE/2]; float pm twid_i[FFT_SIZE/2]; twidfftf(twid_r,twid_i,FFT_SIZE); cfftf(input_r,input_i, temp_r,temp_i, twid_r,twid_i,FFT_SIZE); See Also cfft, cfftN, fftf_magnitude, ifftf, rfftf_2, twidfftf CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-65 Documented Library Functions cmatmadd Complex matrix + matrix addition Synopsis #include complex_float *cmatmaddf (complex_float dm *output, const complex_float dm *a, const complex_float dm *b, int rows, int cols); complex_double *cmatmadd (complex_double dm *output, const complex_double dm *a, const complex_double dm *b, int rows, int cols); complex_long_double *cmatmaddd (complex_long_double dm *output, const complex_long_double dm *a, const complex_long_double dm *b, int rows, int cols); Description The cmatmadd functions perform a complex matrix addition of the input matrix a[][] with input complex matrix b[][], and store the result in the matrix output[][]. The dimensions of these matrices are a[rows][cols], b[rows][cols], and output[rows][cols]. The functions return a pointer to the output matrix. Error Conditions None. 2-66 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define ROWS 4 #define COLS 8 complex_double a[ROWS][COLS], *a_p = (complex_double *) (&a); complex_double b[ROWS][COLS], *b_p = (complex_double *) (&b); complex_double c[ROWS][COLS], *res_p = (complex_double *) (&c); cmatmadd (res_p, a_p, b_p, ROWS, COLS); See Also cmatmmlt, cmatmsub, cmatsadd, matmadd function (and , if are the same size asThe cmatmadf ) uses SIMD; refer to Implications of Using SIMD Mode cmatmadd doubles floats for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-67 Documented Library Functions cmatmmlt Complex matrix * matrix multiplication Synopsis #include complex_float *cmatmmltf (complex_float dm *output, const complex_float dm *a, const complex_float dm *b, int a_rows, int a_cols, int b_cols); complex_double *cmatmmlt (complex_double dm *output, const complex_double dm *a, const complex_double dm *b, int a_rows, int a_cols, int b_cols); complex_long_double *cmatmmltd (complex_long_double dm *output, const complex_long_double dm *a, const complex_long_double dm *b, int a_rows, int a_cols, int b_cols); Description The cmatmmlt functions perform a complex matrix multiplication of the input matrices a[][] and b[][], and return the result in the matrix output[][]. The dimensions of these matrices are a[a_rows][a_cols], b[a_cols][b_cols], and output[a_rows][b_cols]. The functions return a pointer to the output matrix. 2-68 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Algorithm Complex matrix multiplication is defined by the following algorithm: a_cols - 1 Re c i j = Re a i l Re b l j - Im a i l Im b l j l=0 a_cols - 1 Im c i j = Re a i l Im b l j + Im a i l Re b l j l=0 where: i = {0,1,2,...,a_rows-1} j = {0,1,2,...,b_cols-1} Error Conditions None. Example #include #define ROWS_1 4 #define COLS_1 8 #define COLS_2 2 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-69 Documented Library Functions complex_double a[ROWS_1][COLS_1], *a_p = (complex_double *) (&a); complex_double b[COLS_1][COLS_2], *b_p = (complex_double *) (&b); complex_double c[ROWS_1][COLS_2], *r_p = (complex_double *) (&c); cmatmmlt (r_p, a_p, b_p, ROWS_1, COLS_1, COLS_2); See Also cmatmadd, cmatmsub, cmatsmlt, matmmlt 2-70 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cmatmsub Complex matrix - matrix subtraction Synopsis #include complex_float *cmatmsubf (complex_float dm *output, const complex_float dm *a, const complex_float dm *b, int rows, int cols); complex_double *cmatmsub (complex_double dm *output, const complex_double dm *a, const complex_double dm *b, int rows, int cols); complex_long_double *cmatmsubd (complex_long_double dm *output, const complex_long_double dm *a, const complex_long_double dm *b, int rows, int cols); Description The cmatmsub functions perform a complex matrix subtraction between the input matrices a[][] and b[][], and return the result in the matrix output[][]. The dimensions of these matrices are a[rows][cols], b[rows][cols], and output[rows][cols]. The functions return a pointer to the output matrix. Error Conditions None. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-71 Documented Library Functions Example #include #define ROWS 4 #define COLS 8 complex_double a[ROWS][COLS], *a_p = (complex_double *) (&a); complex_double b[ROWS][COLS], *b_p = (complex_double *) (&b); complex_double c[ROWS][COLS], *res_p = (complex_double *) (&c); cmatmsub (res_p, a_p, b_p, ROWS, COLS); See Also cmatmadd, cmatmmlt, cmatssub, matmsub The cmatmsubf function (and , if are the same size ) uses SIMD; refer to Implications of Using SIMD as cmatmsub doubles floats Mode for more information. 2-72 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cmatsadd Complex matrix + scalar addition Synopsis #include complex_float *cmatsaddf (complex_float dm *output, const complex_float dm *a, complex_float scalar, int rows, int cols); complex_double *cmatsadd (complex_double dm *output, const complex_double dm *a, complex_double scalar, int rows, int cols); complex_long_double *cmatsaddd (complex_long_double dm *output, const complex_long_double dm *a, complex_long_double scalar, int rows, int cols); Description The cmatsadd functions add a complex scalar to each element of the complex input matrix a[][] and return the result in the matrix output[][]. The dimensions of these matrices are a[rows][cols] and output[rows][cols]. The functions return a pointer to the output matrix. Error Conditions None. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-73 Documented Library Functions Example #include #define ROWS 4 #define COLS 8 complex_double a[ROWS][COLS], *a_p = (complex_double *) (&a); complex_double c[ROWS][COLS], *res_p = (complex_double *) (&c); complex_double z; cmatsadd (res_p, a_p, z, ROWS, COLS); See Also cmatsmlt, cmatssub, cmatmadd, matsadd cmatsaddf function (and , if are the same The ) uses SIMD; refer to Implications of Using SIMD size as cmatsadd doubles floats Mode for more information. 2-74 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cmatsmlt Complex matrix * scalar multiplication Synopsis #include complex_float *cmatsmltf (complex_float dm *output, const complex_float dm *a, complex_float scalar, int rows, int cols); complex_double *cmatsmlt (complex_double dm *output, const complex_double dm *a, complex_double scalar, int rows, int cols); complex_long_double *cmatsmltd (complex_long_double dm *output, const complex_long_double dm *a, complex_long_double scalar, int rows, int cols); Description The cmatsmlt functions multiply each element of the complex input matrix a[][] with a complex scalar, and return the result in the matrix output[][]. The dimensions of these matrices are a[rows][cols] and output[rows][cols]. The functions return a pointer to the output matrix. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-75 Documented Library Functions Algorithm Complex matrix by scalar multiplication is defined by the following algorithm: Re c i j = Re a i j Re scalar - Im a i j Im scalar Im c i j = Re a i j Im scalar + Im a i j Re scalar where: i = {0,1,2,..., rows-1} j = {0,1,2,..., cols-1} Error Conditions None. Example #include #define ROWS 4 #define COLS 8 complex_double a[ROWS][COLS], *a_p = (complex_double *) (&a); complex_double c[ROWS][COLS], *res_p = (complex_double *) (&c); complex_double z; cmatsmlt (res_p, a_p, z, ROWS, COLS); See Also cmatsadd, cmatssub, cmatmmlt, matsmlt 2-76 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cmatssub Complex matrix - scalar subtraction Synopsis #include complex_float *cmatssubf (complex_float dm *output, const complex_float dm *a, complex_float scalar, int rows, int cols); complex_double *cmatssub (complex_double dm *output, const complex_double dm *a, complex_double scalar, int rows, int cols); complex_long_double *cmatssubd (complex_long_double dm *output, const complex_long_double dm *a, complex_long_double scalar, int rows, int cols); Description The cmatssub functions subtract a complex scalar from each element of the complex input matrix a[][] and return the result in the matrix output[][]. The dimensions of these matrices are a[rows][cols] and output[rows][cols]. The functions return a pointer to the output matrix. Error Conditions None. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-77 Documented Library Functions Example #include #define ROWS 4 #define COLS 8 complex_double a[ROWS][COLS], *a_p = (complex_double *) (&a); complex_double c[ROWS][COLS], *res_p = (complex_double *) (&c); complex_double z; cmatssub (res_p, a_p, z, ROWS, COLS); See Also cmatsadd, cmatsmlt, cmatmsub, matssub function (and , if are the same size asThe cmatssubf ) uses SIMD; refer to Implications of Using SIMD Mode cmatssub doubles floats for more information. 2-78 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cmlt Complex multiplication Synopsis #include complex_float cmltf (complex_float a, complex_float b); complex_double cmlt (complex_double a, complex_double b); complex_long_double cmltd (complex_long_double a, complex_long_double b); Description The cmlt functions compute the complex multiplication of the complex numbers a and b, and return the result. Error Conditions None. Example #include complex_float x = {3.0,11.0}; complex_float y = {1.0, 2.0}; complex_float z; z = cmltf(x,y); /* z.re = -19.0, z.im = 17.0 */ See Also cadd, cdiv, csub CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-79 Documented Library Functions conj Complex conjugate Synopsis #include complex_float conjf (complex_float a); complex_double conj (complex_double a); complex_long_double conjd (complex_long_double a); Description The complex conjugate functions conjugate the complex input a, and return the result. Error Conditions None. Example #include complex_double x = {2.0,8.0}; complex_double z; z = conj(x); /* z = (2.0,-8.0) */ See Also No related functions. 2-80 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library convolve Convolution Synopsis #include float *convolve (const float a[], int asize, const float b[], int bsize, float *output); Description The convolution function calculates the convolution of the input vectors a[] and b[] , and returns the result in the vector output[]. The lengths of these vectors are a[asize], b[bsize], and output[asize+bsize-1]. The convolve function returns a pointer to the output vector. Algorithm Convolution of two vectors is defined as: n ck = aj b k - j j=m where: k = {0, 1, ..., asize + bsize - 2} m = max( 0, k + 1 - bsize) n = min( k, asize - 1) Error Conditions None. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-81 Documented Library Functions Example #include float input[81]; float response[31]; float output[81 + 31 -1]; convolve(input,81,response,31,output); See Also crosscorr 2-82 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library copysign Copy the sign of the floating-point operand. Synopsis #include float copysignf (float x, float y); double copysign (double x, double y); long double copysignd (long double x, long double y); Description The copysign functions copy the sign of the second argument y to the first argument x without changing its exponent or mantissa. The copysignf function is a built-in function which is implemented with an Fn=Fx COPYSIGN Fy instruction. The copysign function is compiled as a built-in function if double is the same size as float. Error Conditions None. Example #include double x; float y; x = copysign (0.5, -10.0); /* x = -0.5 */ y = copysignf (-10.0, 0.5f); /* y = 10.0 */ See Also No related functions. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-83 Documented Library Functions cot Cotangent Synopsis #include float cotf (float x); double cot (double x); long double cotd (long double x); Description The cotangent functions return the cotangent of their argument. The input is interpreted as radians. Error Conditions The input argument x for cotf must be in the domain [-1.647e6, 1.647e6] and the input argument for cotd must be in the domain [-4.21657e8, 4.21657e8]. The functions return zero if x is outside their domain. Example #include #define PI 3.141592653589793 double d; float r; d = cot (-PI/4.0); /* d = -1.0 */ r = cotf( PI/4.0F); /* r = 1.0 2-84 */ CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library See Also tan CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-85 Documented Library Functions crosscoh Cross-coherence Synopsis #include float *crosscohf (float output[], const float x_input[], const float y_input[], int samples, int lags); double *crosscoh (double output[], const double x_input[], const double y_input[], int samples, int lags); long double *crosscohd (long double output[], const long double x_input[], const long double y_input[], int samples, int lags); Description The crosscoh functions perform a cross-coherence between the two signals contained in x_input and y_input, both of length samples. The cross-coherence is the sum of the scalar products of the input signals in which the signals are displaced in time with respect to one another (i.e. the cross-correlation between the input signals), minus the product of the partial mean of x_input and the partial mean of y_input. 2-86 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library The cross-coherence between the two input signals is returned in the array output of length lags. The functions return a pointer to the output array. Error Conditions The crosscoh functions will return without modifying the output array if either the number of samples is less than or equal to 1, or if the number of lags is less than 1, or if the number of lags is not less than the number of samples. Algorithm The cross-coherence functions are based on the following algorithm. 1c k = ---------n-k 1 a j b j + k - ----------n - k n-k-1 j=0 n-1 1 ---------aj b n - k j j=k n-k-1 j=0 where: n = samples k = 0 to lags-1 a = x_input b = y_input CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-87 Documented Library Functions Example #include #define SAMPLES 1024 #define LAGS 16 float x[SAMPLES]; float y[SAMPLES]; float response[LAGS]; crosscohf (response, x, y, SAMPLES, LAGS); See Also autocoh, autocorr, crosscorr 2-88 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library crosscorr Cross-correlation Synopsis #include float *crosscorrf (float dm out[], const float dm x[], const float dm y[], int samples, int lags); double *crosscorr (double dm out[], const double dm x[], const double dm y[], int samples, int lags); long double *crosscorrd (long double dm out[], const long double dm x[], const long double dm y[], int samples, int lags); Description The cross-correlation functions perform a cross-correlation between two signals. The cross-correlation is the sum of the scalar products of the signals in which the signals are displaced in time with respect to one another. The signals to be correlated are given by the input arrays x[] and y[]. The length of the input arrays is given by samples. The functions return a pointer to the output data array out[] of length lags. Cross-correlation is used in signal processing applications such as speech analysis. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-89 Documented Library Functions Algorithm The following equation is the basis of the algorithm. n-k-1 1--- c k = a j b j + k n j=0 where: k = {0, 1, ..., lags-1} a=x b=y n = samples Error Conditions None. Example #include #define SAMPLES 1024 #define LAGS 16 double excitation[SAMPLES], y[SAMPLES]; double response[LAGS]; int lags = LAGS; crosscorr (response, excitation, y, SAMPLES, lags); 2-90 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library See Also autocoh, autocorr, crosscoh The crosscorrf function (and , if are the same size as ) uses SIMD; refer to Implications of Using SIMD crosscorr doubles floats Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-91 Documented Library Functions csub Complex subtraction Synopsis #include complex_float csubf (complex_float a, complex_float b); complex_double csub (complex_double a, complex_double b); complex_long_double csubd (complex_long_double a, complex_long_double b); Description The csub functions subtract the two complex values a and b, and return the result. Error Conditions None. Example #include complex_float x = {9.0,16.0}; complex_float y = {1.0,-1.0}; complex_float z; z = csubf(x,y); /* z.re = 8.0, z.im = 17.0 */ See Also cadd, cdiv, cmlt 2-92 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cvecdot Complex vector dot product Synopsis #include complex_float cvecdotf (const complex_float dm a[], const complex_float dm b[], int samples); complex_double cvecdot (const complex_double dm a[], const complex_double dm b[], int samples); complex_long_double cvecdotd (const complex_long_double dm a[], const complex_long_double dm b[], int samples); Description The cvecdot functions compute the complex dot product of the complex vectors a[] and b[], which are samples in size. The scalar result is returned by the function. Algorithm The algorithm for a complex dot product is given by: n-1 Re c i = Re ai Re bi - Im ai Im bi l=0 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-93 Documented Library Functions n-1 Re ai Im bi + Im ai Re bi Im c i = l=0 where: i = {0,1,2,...,samples-1} Error Conditions None. Example #include #define N 100 complex_float x[N], y[N]; complex_float answer; answer = cvecdotf (x, y, N); See Also vecdot 2-94 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cvecsadd Complex vector + scalar addition Synopsis #include complex_float *cvecsaddf (const complex_float dm a[], complex_float scalar, complex_float dm output[], int samples); complex_double *cvecsadd (const complex_double dm a[], complex_double scalar, complex_double dm output[], int samples); complex_long_double *cvecsaddd (const complex_long_double dm a[], complex_long_double scalar, complex_long_double dm output[], int samples); Description The cvecsadd functions compute the sum of each element of the complex vector a[], added to the complex scalar. Both the input and output vectors are samples in size. The functions return a pointer to the output vector. Error Conditions None. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-95 Documented Library Functions Example #include #define N 100 complex_float input[N], result[N]; complex_float x; cvecsaddf (input, x, result, N); See Also cvecsmlt, cvecssub, cvecvadd, vecsadd cvecsaddf function (and , if are the same size The as ) uses SIMD by default. Refer to Implications of Using cvecsadd doubles floats SIMD Mode for more information. 2-96 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cvecsmlt Complex vector * scalar multiplication Synopsis #include complex_float *cvecsmltf (const complex_float dm a[], complex_float scalar, complex_float dm output[], int samples); complex_double *cvecsmlt (const complex_double dm a[], complex_double scalar, complex_double dm output[], int samples); complex_long_double *cvecsmltd (const complex_long_double dm a[], complex_long_double scalar, complex_long_double dm output[], int samples); Description The cvecsmlt functions compute the product of each element of the complex vector a[], multiplied by the complex scalar. Both the input and output vectors are samples in size. The functions return a pointer to the output vector. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-97 Documented Library Functions Complex vector by scalar multiplication is given by the formula: Re(ci) = Re(ai)*Re(scalar) - Im(ai)*Im(scalar) Im(ci) = Re(ai)*Im(scalar) + Im(ai)*Re(scalar) where: i = {0,1,2,...,samples-1} Error Conditions None. Example #include #define N 100 complex_float input[N], result[N]; complex_float x; cvecsmltf (input, x, result, N); See Also cvecsadd, cvecssub, cvecvmlt, vecsmlt 2-98 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cvecssub Complex vector - scalar subtraction Synopsis #include complex_float *cvecssubf (const complex_float dm a[], complex_float scalar, complex_float dm output[], int samples); complex_double *cvecssub (const complex_double dm a[], complex_double scalar, complex_double dm output[], int samples); complex_long_double *cvecssubd (const complex_long_double dm a[], complex_long_double scalar, complex_long_double dm output[], int samples); Description The cvecssub functions compute the difference of each element of the complex vector a[], minus the complex scalar. Both the input and output vectors are samples in size. The functions return a pointer to the output vector. Error Conditions None. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-99 Documented Library Functions Example #include #define N 100 complex_float input[N], result[N]; complex_float x; cvecssubf (input, x, result, N); See Also cvecsadd, cvecsmlt, cvecvsub, vecssub function (and , if are the same size asThe cvecssubf ) uses SIMD by default. Refer to Implications of Using cvecssub doubles floats SIMD Mode for more information. 2-100 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cvecvadd Complex vector + vector addition Synopsis #include complex_float *cvecvaddf (const complex_float dm a[], const complex_float dm b[], complex_float dm output[], int samples); complex_double *cvecvadd (const complex_double dm a[], const complex_double dm b[], complex_double dm output[] int samples); complex_long_double *cvecvaddd (const complex_long_double dm a[], const complex_long_double dm b[], complex_long_double dm output[], int samples); Description The cvecvadd functions compute the sum of each of the elements of the complex vectors a[] and b[], and store the result in the output vector. All three vectors are samples in size. The functions return a pointer to the output vector. Error Conditions None. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-101 Documented Library Functions Example #include #define N 100 complex_float input_1[N]; complex_float input_2[N], result[N]; cvecvaddf (input_1, input_2, result, N); See Also cvecsadd, cvecvmlt, cvecvsub, vecvadd cvecvaddf function (and , if are the same size The as ) uses SIMD by default. Refer to Implications of Using cvecvadd doubles floats SIMD Mode for more information. 2-102 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cvecvmlt Complex vector * vector multiply Synopsis #include complex_float *cvecvmltf (const complex_float dm a[], const complex_float dm b[], complex_float dm output[], int samples); complex_double *cvecvmlt (const complex_double dm a[], const complex_double dm b[], complex_double dm output[], int samples); complex_long_double *cvecvmltd (const complex_long_double dm a[], const complex_long_double dm b[], complex_long_double dm output[], int samples); Description The cvecvmlt functions compute the product of each of the elements of the complex vectors a[] and b[], and store the result in the output vector. All three vectors are samples in size. The functions return a pointer to the output vector. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-103 Documented Library Functions Complex vector multiplication is given by the formula: Re(ci) = Re(ai)*Re(bi) - Im(ai)*Im(bi) Im(ci) = Re(ai)*Im(bi) + Im(ai)*Re(bi) where: i = {0,1,2,...,samples-1} Error Conditions None. Example #include #define N 100 complex_float input_1[N]; complex_float input_2[N], result[N]; cvecvmltf (input_1, input_2, result, N); See Also cvecsmlt, cvecvadd, cvecvsub, vecvmlt apply to this function if the data is placed in external Restrictions memory. See Using Data in External Memory for more information. function uses long word access instructions. If the input data This is in a memory block where extended precision 40-bit accesses are enabled (i.e. where the IMDWx bit is set), then the input data will be read incorrectly. Only use this function when the input data is in a block that is configured for 32-bit data accesses. 2-104 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library cvecvsub Complex vector - vector subtraction Synopsis #include complex_float *cvecvsubf (const complex_float dm a[], const complex_float dm b[], complex_float dm output[], int samples); complex_double *cvecvsub (const complex_double dm a[], const complex_double dm b[], complex_double dm output[], int samples); complex_long_double *cvecvsubd (const complex_long_double dm a[], const complex_long_double dm b[], complex_long_double dm output[], int samples); Description The cvecvsub functions compute the difference of each of the elements of the complex vectors a[] and b[], and store the result in the output vector. All three vectors are samples in size. The functions return a pointer to the output vector. Error Conditions None. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-105 Documented Library Functions Example #include #define N 100 complex_float input_1[N]; complex_float input_2[N], result[N]; cvecvsubf (input_1, input_2, result, N); See Also cvecssub, cvecvadd, cvecvmlt, vecvsub cvecvsubf function (and , if are the same size The as ) uses SIMD by default. Refer to Implications of Using cvecvsub doubles floats SIMD Mode for more information. 2-106 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library favg Mean of two values Synopsis #include float favgf (float x, float y); double favg (double x, double y); long double favgd (long double x, long double y); Description The favg functions return the mean of their two arguments. The favgf function is a built-in function which is implemented with an Fn=(Fx+Fy)/2 instruction. The favg function is compiled as a built-in function if double is the same size as float. Error Conditions None. Example #include float x; x = favgf (10.0f, 8.0f); /* returns 9.0f */ See Also avg, lavg CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-107 Documented Library Functions fclip Clip Synopsis #include float fclipf (float x, float y); double fclip (double x, double y); long double fclipd (long double x, long double y); Description The fclip functions return the first argument if its absolute value is less than the absolute value of the second argument, otherwise they return the absolute value of the second argument if the first is positive, or minus the absolute value if the first argument is negative. The fclipf function is a built-in function which is implemented with an Fn=CLIP Fx BY Fy instruction. The fclip function is compiled as a built-in function if double is the same size as float. Error Conditions None. Example #include float y; y = fclipf (5.1f, 8.0f); /* returns 5.1f */ See Also clip, clip 2-108 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library fft_magnitude FFT magnitude Synopsis #include float *fft_magnitude (complex_float input[], float output[], int fftsize, int mode); Description The fft_magnitude function computes a normalized power spectrum from the output signal generated by an FFT function; the mode parameter is used to specify which FFT function has been used to generate the input array. If the input array has been generated by the cfft function, the mode must be set to 0. In this case the input array and the power spectrum are of size fftsize. If the input array has been generated by the rfft function, mode must be set to 2. In this case the input array and the power spectrum are of size ((fftsize / 2) + 1). The fft_magnitude function may also be used to calculate the power spectrum of an FFT that was generated by the cfftN and rfftN functions. If the input array has been generated by the rfftN function, then mode must be set to 1, and the size of the input array and the power spectrum will be (fftsize / 2). If the input array was generated by the cfftN function, then the mode must be set to 0 and the size of the input array and the power spectrum will be fftsize (as for the cfft function above). The fft_magnitude function returns a pointer to the output. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-109 Documented Library Functions fft_magnitude function provides the same functionality as the The cfft_mag and rfft_mag function does. In addition, it provides a real FFT power spectrum that includes the Nyquist frequency (only in conjunction with the rfft function). The fft_magnitude function uses SIMD by default. Refer to Implications of Using SIMD Mode for more information. Error Conditions None. Algorithm For mode 0 (cfft and cfftN generated input): 2 2 Re a z + Im a z magnitude z = ----------------------------------------------------------fftsize For mode 1 and 2 (rfftN and rfft generated input): magnitude z = 2-110 2 2 2 Re a z + Im a z -----------------------------------------------------------fftsize CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define N_FFT 64 #define N_RFFT_OUT ((N_FFT / 2) + 1) /* Data for real FFT */ float rfft_input[N_FFT]; complex_float rfft_output[N_RFFT_OUT]; complex_float rfftN_output[N_RFFT_OUT - 1]; /* Data for complex FFT */ complex_float cfft_input[N_FFT]; complex_float cfft_output[N_RFFT_OUT]; complex_float pm twiddle[N_FFT / 2]; complex_float temp[N_FFT]; float *tmp = (float*)temp; /* Power Spectrums */ float rspectrum[N_RFFT_OUT]; float rNspectrum[N_RFFT_OUT - 1]; float cspectrum[N_FFT]; /* Initialize */ twidfft(twiddle, N_FFT); /* Power spectrum using rfft */ rfft (rfft_input, tmp, rfft_output, twiddle, 1, N_FFT); fft_magnitude (rfft_output, rspectrum, N_FFT, 2); rfft64 (rfft_input, rfftN_output); fft_magnitude (rfftN_output, rNspectrum, N_FFT, 1); CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-111 Documented Library Functions /* Power spectrum using cfft */ cfft (cfft_input, temp, cfft_output, twiddle, 1, N_FFT); fft_magnitude (cfft_output, cspectrum, N_FFT, 0); See Also cfft, cfftN, cfft_mag, fftf_magnitude, rfft, rfft_mag, rfftN 2-112 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library fftf_magnitude fftf magnitude Synopsis #include float *fftf_magnitude (float input_real[], float input_imag[], float output[], int fftsize, int mode); Description The fftf_magnitude function computes a normalized power spectrum from the output signal generated by one of the accelerated FFT functions cfftf or rfftf_2. The mode argument is used to specify which FFT function has been used. If the input array has been generated by the cfftf function, mode must be set to 0. In this case the input array and the power spectrum are of size fftsize. If the input array has been generated by the rfftf_2 function, mode must be set to 2. In this case the input array will contain a signal that is symmetrical about its midpoint and so the function will only use the first ((fftsize / 2) + 1) input samples to compute the power spectrum. The size of the generated power spectrum will be ((fftsize / 2) + 1). The fftf_magnitude function returns a pointer to the output. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-113 Documented Library Functions Algorithm For mode 0 (cfftf generated input): 2 2 Re z + Im z magnitude z = -----------------------------------------------------fftsize For mode 2 (rfftf_2 generated input): 2 magnitude z = 2 Re z + Im z 2 ----------------------------------------------------fftsize Error Conditions None. Example #include #define N_FFT 64 #define N_RFFT_OUT ((N_FFT / 2) + 1) float pm twiddle_re[N_FFT/2]; float dm twiddle_im[N_FFT/2]; #pragma align 64 float dm rfft1_re[N_FFT]; float dm rfft1_im[N_FFT]; 2-114 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library #pragma align 64 float pm rfft2_re[N_FFT]; float pm rfft2_im[N_FFT]; #pragma align 64 float dm data_re[N_FFT]; float pm data_im[N_FFT]; #pragma align 64 float dm temp_re[N_FFT]; float pm temp_im[N_FFT]; float rspectrum_1[N_RFFT_OUT]; float rspectrum_2[N_RFFT_OUT]; float cspectrum[N_FFT]; twidfftf(twiddle_re, twiddle_im, N_FFT); rfftf_2(rfft1_re, rfft1_im, rfft2_re, rfft2_im, twiddle_re, twiddle_im, N_FFT); fftf_magnitude(rfft1_re, rfft1_im, rspectrum_1, N_FFT, 2); fftf_magnitude(rfft2_re, rfft2_im, rspectrum_2, N_FFT, 2); cfftf(data_re, data_im, temp_re, temp_im, twiddle_re, twiddle_im, N_FFT); fftf_magnitude(data_re, data_im, cspectrum, N_FFT, 0); See Also cfftf, rfftf_2 this function uses SIMD. Refer to Implications of ByUsingdefault, SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-115 Documented Library Functions fir finite impulse response (FIR) filter Synopsis (Scalar-Valued Version) #include float fir (float sample, const float pm coeffs[], float dm state[], int taps); Synopsis (Vector-Valued Version) #include float *fir (const float float dm input[], dm output[], const float pm coeffs[], float dm state[], int samples, int taps); Description The fir functions implement a finite impulse response (FIR) filter that is structured as a sum of products. The characteristics of the filter (passband, stop band, and so on) are dependent on the coefficients and the number of taps supplied by the calling program. The scalar version of the fir function produces the filtered response of its input data sample, which it returns as the result of the function. The vector versions of the fir function generate the filtered response of the input data input and store the result in the output vector output. The 2-116 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library number of input samples and the length of the output vector is specified by the argument samples. The number of coefficients is specified by the parameter taps and the coefficients must be stored in reverse order in the array coeffs; so coeffs[0] contains the last filter coefficent and coeffs[taps-1] contains the first coefficient. The array must be located in program memory data space so that the single-cycle dual-memory fetch of the processor can be used. Each filter should have its own delay line, which is represented by the array state. The array contains a pointer into the delay line as its first element, followed by the delay line values. The length of the state array is therefore one greater than the number of taps. The state array should be initially cleared to zero before calling the function for the first time, and should not otherwise be modified by the user program. library function uses the architecture's dual-data move instruc The tion to provide simultaneous access to the filter coefficients (in PM data memory) and the delay line. When running on an ADSP-21367, ADSP-21368 or ADSP-21369 processor, the filter coefficients and the delay line must not both be allocated in external memory; otherwise, the function can generate an incorrect set of results. This occurs because in a dual-data move instruction, the hardware does not support both memory accesses allocated to external memory. Therefore, ensure that the filter coefficients or the delay line (or, optionally, both) are allocated in internal memory when running on one of the ADSP-2136x processors specified above. The vector version of the fir functions return a pointer to the output vector; the scalar version of the function returns the filtered response of its input sample. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-117 Documented Library Functions Error Conditions None. Example Scalar-Valued #include #define TAPS 10 float y; float pm coeffs[TAPS]; /* coeffs array must be */ /* initialized and in PM memory */ float state[TAPS+1]; int i; for (i = 0; i < TAPS+1; i++) state[i] = 0; /* initialize state array */ y = fir (0.775, coeffs, state, TAPS); /* y holds the filtered output */ /* coeffs array must be */ Vector-Valued #include #define TAPS 10 #define SAMPLES 256 float input[SAMPLES]; float output[SAMPLES]; float pm coeffs[TAPS]; /* initialized and in PM memory */ float state[TAPS+1]; 2-118 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library int i; for (i = 0; i < TAPS+1; i++) state[i] = 0; /* initialize state array */ fir (input, output, coeffs, state, SAMPLES, TAPS); See Also biquad, fir_decima, fir_interp, firf, iir default, the vector version of the fir function uses SIMD. Refer Byto Implications of Using SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-119 Documented Library Functions fir_decima FIR-based decimation filter Synopsis #include float *fir_decima (const float input[], float output[], const float pm coefficients[], float delay[], int num_output_samples, int num_coeffs, int decimation_index); Description The fir_decima function implements a finite impulse response (FIR) filter defined by the coefficients and the delay line that are supplied in the call of fir_decima. The function produces the filtered response of its input data and then decimates. The size of the output vector output is specified by the argument num_output_samples, which specifies the number of output samples to be generated. The input vector input should contain decimation_index * num_output_samples samples, where decimation_index represents the decimation index. The characteristics of the filter are dependent on the number of coefficients and their values, and the decimation index supplied by the calling program. The array of filter coefficients coefficients must be located in Program Memory (PM) data space so that the single cycle dual memory fetch of the processor can be used. The argument num_coeffs defines the number of coefficients, which must be stored in reverse order. Thus coefficients[0] 2-120 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library contains the last filter coefficient, and coefficients[num_coeffs-1] contains the first. The delay line has the size num_coeffs + 1. Before the first call, all elements must be set to zero. The first element in the delay line holds the read/write pointer being used by the function to mark the next location in the delay line to write to. The pointer should not be modified outside this function. It is needed to support the restart facility, whereby the function can be called repeatedly, carrying over previous input samples using the delay line. The fir_decima function returns the address of the output array. library function uses the architecture's dual-data move instruc The tion to provide simultaneous access to the filter coefficients (in PM data memory) and the delay line. When running on an ADSP-21367, ADSP-21368 or ADSP-21369 processor, the filter coefficients and the delay line must not both be allocated in external memory; otherwise, the function can generate an incorrect set of results. This occurs because in a dual-data move instruction, the hardware does not support both memory accesses allocated to external memory. Therefore, ensure that the filter coefficients or the delay line (or, optionally, both) are allocated in internal memory when running on one of the ADSP-2136x processors specified above. Algorithm The following equation is the basis for the algorithm: k-1 yi = xi l - j hk - 1 - j j=0 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-121 Documented Library Functions where: i = 0, 1, .., num_output_samples-1 n = num_output_samples k = num_coeffs l = decimation_index Error Conditions None. Example #include #define N_DECIMATION 4 #define N_SAMPLES_OUT 128 #define N_SAMPLES_IN (N_SAMPLES_OUT * N_DECIMATION) #define N_COEFFS 33 float input[N_SAMPLES_IN]; float output[N_SAMPLES_OUT]; float delay[N_COEFFS + 1]; float pm coeffs[N_COEFFS]; int i; /* Initialize the delay line */ for (i = 0; i < (N_COEFFS + 1); i++) delay[i] = 0.0F; fir_decima(input, output, coeffs, delay, N_SAMPLES_OUT, N_COEFFS, N_DECIMATION); See Also fir, fir_interp 2-122 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library fir_interp FIR interpolation filter Synopsis #include float *fir_interp (const float input[], float output[], const float pm coefficients[], float delay[], int num_input_samples, int num_coeffs, int interp_index); Description The fir_interp function implements a finite impulse response (FIR) filter defined by the coefficients and the delay line supplied in the call of fir_interp. It generates the interpolated filtered response of the input data input and stores the result in the output vector output. To boost the signal power, the filter response is multiplied by the interpolation index interp_index before it is stored in the output array. The number of input samples is specified by the argument num_input_samples. The size of the output vector should be num_input_samples*interp_index, where interp_index represents the interpolation index. The array of filter coefficients coefficients must be located in Program Memory data space (PM) so that the single-cycle dual-memory fetch of the processor can be used. The array must contain interp_index sets of polyphase coefficients, where the number of polyphases in the filter is equal to the interpolation index. The number of coefficients per polyphase CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-123 Documented Library Functions is specified by the argument num_coeffs, and therefore the total length of the array coefficients is of size num_coeffs*interp_index. The fir_interp function assumes that the filter coefficients will be stored in the following order: coefficients[coeffs coeffs for 1st polyphase in reverse order for 2nd polyphase in reverse order . . . . . . . . . . . . . . . . . . coeffs for interp_index'th polyphase in reverse order] The following example shows how the filter coefficients should be ordered for the simple case when the interpolation index is set to 1, and when the number of coefficients is 12. (Note that an interpolation index of 1 implies no interpolation, and that in this case the order of the coefficients is the same order as used by the fir and fir_decima functions). c11,c10,c9,c8,c7,c6,c5,c4,c3,c2,c1,c0 If the interpolation index is set to 3, then the above set of coefficients should be re-ordered into three sets of polyphase coefficients in reverse order as follows: c9,c6,c3,c0, c10,c7,c4,c1, c11,c8,c5,c2 where the 1st set of polyphase coefficients c9, c6, c3, and c0 are used to compute output[k], the 2nd set of polyphase coefficients c10, c7, c4, and rd c1 are used to compute output[k+1], and the 3 set of polyphase coefficients c11, c8, c5, and c2 are used to compute output[k+2]. 2-124 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library In general, the re-ordering can be expressed by the following formula: npoly = interp_index; for (np = 1, i = (num_coeffs*npoly); np <= npoly; np++) for (nc = 1; nc <= (num_coeffs; nc++) coeffs[--i] = filter_coeffs[(nc * npoly) - np]; where filter_coeffs[] represents the normal order coefficients. The delay line has the size num_coeffs + 1. Before the first call, all elements must be set to zero. The first element in the delay line contains the read/write pointer used by the function to mark the next location in the delay line to write to. The pointer should not be modified outside this function. It is needed to support the restart facility, whereby the function can be called repeatedly, carrying over previous input samples using the delay line. The fir_interp function returns the address of the output array. library function uses the architecture's dual-data move instruc The tion to provide simultaneous access to the filter coefficients (in PM data memory) and the delay line. When running on an ADSP-21367, ADSP-21368 or ADSP-21369 processor, the filter coefficients and the delay line must not both be allocated in external memory; otherwise, the function can generate an incorrect set of results. This occurs because in a dual-data move instruction, the hardware does not support both memory accesses allocated to external memory. Therefore, ensure that the filter coefficients or the delay line (or, optionally, both) are allocated in internal memory when running on one of the ADSP-2136x processors specified above. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-125 Documented Library Functions Algorithm The algorithm for this function is given by: k-1 yi p + m = xi - j hm k + k - 1 - j j=0 where: i = {0,1,2,...,num_input_samples-1} m = {0,1,2,...,interp_index-1} n = num_input_samples p = interp_index k = num_coeffs Error Conditions None. Example #include #define N_INTERP 4 #define N_POLYPHASES (N_INTERP) #define N_SAMPLES_IN 128 #define N_SAMPLES_OUT (N_SAMPLES_IN * N_INTERP) #define N_COEFFS_PER_POLY 33 #define N_COEFFS (N_COEFFS_PER_POLY * N_POLYPHASES) float input[N_SAMPLES_IN]; float output[N_SAMPLES_OUT]; 2-126 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library float delay[N_COEFFS_PER_POLY + 1]; /* Coefficients in normal order */ float filter_coeffs[N_COEFFS]; /* Coefficients in implementation order */ float pm coeffs[N_COEFFS]; int i, nc, np, scale; /* Initialize the delay line */ for (i = 0; i < (N_COEFFS_PER_POLY + 1); i++) delay[i] = 0.0F; /* Transform the normal order coefficients from a filter design tool into coefficients for the fir_interp function */ i = N_COEFFS; for (np = 1, np <= N_POLYPHASES; np++) for (nc = 1; nc <= (N_COEFFS_PER_POLY); nc++) coeffs[--i] = filter_coeffs[(nc * N_POLYPHASES) - np]; fir_interp (input, output, coeffs, delay, N_SAMPLES_IN, N_COEFFS_PER_POLY, N_INTERP); /* Adjust output */ scale = N_INTERP; for (i = 0; i < N_SAMPLES_OUT; i++) output[i] = output[i] / scale; See Also fir, fir_decima CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-127 Documented Library Functions firf Fast Finite Impulse Response (FIR) filter Synopsis #include void *firf(const float float input[], output[], const float pm coefficients[], float state[], int samples, int taps); Description The firf function implements an accelerated finite impulse response (FIR) filter. The function generates the filtered response of the input data input and stores the result in the output vector output. The number of input samples and the length of the output vector are specified by the parameter samples. The number of samples must be even and at least 4. The function will ignore the last sample if the number of samples is odd. The number of coefficients is specified by the parameters taps. The number of coefficients must be even and at least 8. If the number of filter coefficients is odd, then an application could round the number of coefficients up to the next even number and set the extra coefficient to 0. The filter coefficients must be stored in reverse order in the array coefficients. Thus coefficients[0] contains the last filter coefficient and coefficients[taps-1] contains the first coefficient. The array should be located in a different memory section than the state array (see below) so that the single-cycle, dual-memory fetch of the processor can be used. Each filter should have its own delay line, which is represented by the array state. The length of the state array is the number of taps + 1. The 2-128 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library state array should be initially cleared to zero before calling the function for the first time, and should not otherwise be modified by the user program. library function uses the architecture's dual-data move instruc The tions to provide simultaneous access to the filter coefficients (in PM data memory) and the delay line. When running on a ADSP-21367, ADSP-21368, or ADSP-21369 processor, the delay line and filter coefficients must not both be allocated in external memory otherwise the function may generate an incorrect set of results. This may happen because the hardware does not support a dual-data move instruction that generates two accesses to external memory. Therefore ensure that either the filter coefficients or the delay line (or, optimally, both) are allocated in internal memory when running on one of the ADSP-2136x processors specified above. To provide optimal performance, the function uses the architecture's SIMD mode and also makes use of certain user-reservable registers. It is therefore important to note the following constraints concerning the use of the function: * Refer to Implications of Using SIMD Mode and to the section "A Brief Introduction to SIMD Mode" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors for further information concerning the use of SIMD. A non-SIMD version of this function is not provided. * Under the C/C++ Run-Time Model, certain registers are defined as Reservable Registers (refer to the section "Reservable Registers" in Chapter 1 of the C/C++ Compiler Manual for SHARC Processors). Normally the run-time library will avoid using these registers. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-129 Documented Library Functions However, the firf function will make use of the following registers, preserving their contents on entry to the function and restoring them on exit: B1, I1, L1 Therefore applications that use the compiler's -reserve switch to reserve the above registers should not use the firf function. The constraints imposed by the firf function may not meet the requirements of an application; in cases such as these, applications can instead use the fir function which has the same functionality as the firf function but none of its restrictions. The function returns a pointer to the output array. Algorithm The algorithm is based on: output[i] = sum (h[k] * x[i-j]) where: x = input h = array of coefficients i = { 0, 1, ..., samples-1 } j = { 0, 1, ..., taps-1 } k = { taps-1, taps-2, ..., 0 } Error Conditions None. 2-130 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define TAPS 64 #define SAMPLES 512 float input[SAMPLES]; float output[SAMPLES]; float pm coeffs[TAPS]; /* coeffs array must be */ /* initialized and in PM memory */ float state[TAPS+1]; int i; for (i = 0; i < (TAPS+1); i++) state[i] = 0; /* initialize state array */ for (;;) { /* acquire a new set of input data */ /* compute filtered response for current set of data */ firf (input, output, coeffs, state, SAMPLES, TAPS); /* post-process filtered response */ } See Also fir CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-131 Documented Library Functions fmax float maximum Synopsis #include float fmaxf (float x, float y); double fmax (double x, double y); long double fmaxd (long double x, long double y); Description The fmax functions return the larger of their two arguments. The fmaxf function is a built-in function which is implemented with an Fn=MAX(Fx,Fy) instruction. The fmax function is compiled as a built-in function if double is the same size as float. Error Conditions None. Example #include float y; y = fmaxf (5.1f, 8.0f); /* returns 8.0f */ See Also fmin, llmax, llmin, max, min 2-132 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library fmin float minimum Synopsis #include float fminf (float x, float y); double fmin (double x, double y); long double fmind (long double x, long double y); Description The fmin functions return the smaller of their two arguments. The fminf function is a built-in function which is implemented with an Fn=MIN(Fx,Fy) instruction. The fmin function is compiled as a built-in function if double is the same size as float. Error Conditions None. Example #include float y; y = fminf (5.1f, 8.0f); /* returns 5.1f */ See Also fmax, llmax, llmin, max, min CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-133 Documented Library Functions gen_bartlett Generate Bartlett window Synopsis #include void gen_bartlett (float dm w[], int a, int N); Description The gen_bartlett function generates a vector containing the Bartlett window. The length is specified by parameter N, and the stride parameter a is used to space the window values within the output vector w. The length of the output vector should therefore be N*a. The Bartlett window is similar to the triangle window (see gen_triangle) but has the following different properties: * The Bartlett window returns a window with two zeros on either end of the sequence. Therefore, for odd n, the center section of a N+2 Bartlett window equals an N triangle window. * For even n, the Bartlett window is the convolution of two rectangular sequences. There is no standard definition for the triangle window for even n; the slopes of the triangle window are slightly steeper than those of the Bartlett window. 2-134 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Algorithm The algorithm for this function is given by: N-1 n - ------------2 w n = 1 - --------------------N - 1-----------2 where: n = {0, 1, 2, ..., N-1} Domain a > 0; N > 0 Error Conditions None. See Also gen_blackman, gen_gaussian, gen_hamming, gen_hanning, gen_harris, gen_kaiser, gen_rectangular, gen_triangle, gen_vonhann CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-135 Documented Library Functions gen_blackman Generate Blackman window Synopsis #include void gen_blackman (float dm w[], int a, int N); Description The gen_blackman function generates a vector containing the Blackman window. The length of the required window is specified by the parameter N, and the stride parameter a is used to space the window values within the output vector w. The length of the output vector should therefore be N*a. Algorithm The algorithm for this function is given by: 2n 4n w n = 0.42 - 0.5 cos ------------- + 0.08 cos ------------N-1 N-1 where: n = {0, 1, 2, ..., N-1} Domain a > 0; N > 0 2-136 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Error Conditions None. See Also gen_bartlett, gen_gaussian, gen_hamming, gen_hanning, gen_harris, gen_kaiser, gen_rectangular, gen_triangle, gen_vonhann CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-137 Documented Library Functions gen_gaussian Generate Gaussian window Synopsis #include void gen_gaussian (float dm w[], float alpha, int a, int N); Description The gen_gaussian function generates a vector containing the Gaussian window. The length of the required window is specified by the parameter N, and the stride parameter a is used to space the window values within the output vector w. The length of the output vector should therefore be N*a. The parameter alpha is used to control the shape of the window. In general, the peak of the Gaussian window will become narrower and the leading and trailing edges will tend towards zero the larger that alpha becomes. Conversely, the peak will get wider the more that alpha tends towards zero. Algorithm The algorithm for this function is given by: 2 n-N ---- + 1--- 1 2 2 w n = exp - --- ----------------------- 2 N --- 2 2-138 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library where: n = {0, 1, 2, ..., N-1} and a is an input parameter Domain a > 0; N > 0; a > 0.0 Error Conditions None. See Also gen_bartlett, gen_blackman, gen_hamming, gen_hanning, gen_harris, gen_kaiser, gen_rectangular, gen_triangle, gen_vonhann CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-139 Documented Library Functions gen_hamming Generate Hamming window Synopsis #include void gen_hamming (float dm w[], int a, int N); Description The gen_hamming function generates a vector containing the Hamming window. The length of the required window is specified by the parameter N, and the stride parameter a is used to space the window values within the output vector w. The length of the output vector should therefore be N*a. Algorithm The algorithm for this function is given by: 2n w n = 0.54 - 0.46 cos ------------- N-1 where: n = {0, 1, 2, ..., N-1} Domain a > 0; N > 0 2-140 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Error Conditions None. See Also gen_bartlett, gen_blackman,gen_gaussian, gen_hanning, gen_harris, gen_kaiser, gen_rectangular, gen_triangle, gen_vonhann CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-141 Documented Library Functions gen_hanning Generate Hanning window Synopsis #include void gen_hanning (float dm w[], int a, int N); Description The gen_hanning function generates a vector containing the Hanning window. The length of the required window is specified by the parameter N, and the stride parameter a is used to space the window values within the output vector w. The length of the output vector should therefore be N*a. This window is also known as the Cosine window. Algorithm The following equation is the basis of the algorithm. 2n w n = 0.5 - 0.5 cos ------------- N - 1 where: n = {0, 1, 2, ..., N-1} Domain a > 0; N > 0 2-142 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Error Conditions None. See Also gen_bartlett, gen_blackman,gen_gaussian, gen_hamming, gen_harris, gen_kaiser, gen_rectangular, gen_triangle, gen_vonhann CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-143 Documented Library Functions gen_harris Generate Harris window Synopsis #include void gen_harris (float dm w[], int a, int N); Description The gen_harris function generates a vector containing the Harris window. The length of the required window is specified by the parameter N, and the stride parameter a is used to space the window values within the output vector w. The length of the output vector should therefore be N*a. This window is also known as the Blackman-Harris window. Algorithm The following equation is the basis of the algorithm. 2n 4n 6n w[n] = 0.35875 - 0.48829 cos ------------- + 0.14128 cos ------------- - 0.01168 cos ------------- N-1 N-1 N-1 where: n = {0, 1, 2, ..., N-1} Domain a > 0; N > 0 2-144 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Error Conditions None. See Also gen_bartlett, gen_blackman,gen_gaussian, gen_hamming, gen_hanning, gen_kaiser, gen_rectangular, gen_triangle, gen_vonhann CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-145 Documented Library Functions gen_kaiser Generate Kaiser window Synopsis #include void gen_kaiser (float dm w[], int a, int N); Description The gen_kaiser function generates a vector containing the Kaiser window. The length of the required window is specified by the parameter N, and the stride parameter a is used to space the window values within the output vector w. The length of the output vector should therefore be N*a. The b value is specified by parameter beta. Algorithm The following equation is the basis of the algorithm. 1--- n- 2 2 I 0 1 - ------------ w n = ---------------------------------------------------I0 2-146 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library where: n = {0, 1, 2, ..., N-1} = (N - 1) / 2 I0() represents the zeroth-order modified Bessel function of the first kind Domain a > 0; N > 0; b > 0.0 Error Conditions None. See Also gen_bartlett, gen_blackman,gen_gaussian, gen_hamming, gen_hanning, gen_harris, gen_rectangular, gen_triangle, gen_vonhann CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-147 Documented Library Functions gen_rectangular Generate rectangular window Synopsis #include void gen_rectangular (float dm w[], int a, int N); Description The gen_rectangular function generates a vector containing the rectangular window. The length of the required window is specified by the parameter N, and the stride parameter a is used to space the window values within the output vector w. The length of the output vector should therefore be N*a. Algorithm w[n] = 1 where: n = {0, 1, 2, ..., N-1} Domain a > 0; N > 0 Error Conditions None. 2-148 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library See Also gen_bartlett, gen_blackman,gen_gaussian, gen_hamming, gen_hanning, gen_harris, gen_kaiser, gen_triangle, gen_vonhann CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-149 Documented Library Functions gen_triangle Generate triangle window Synopsis #include void gen_triangle (float dm w[], int a, int N); Description The gen_triangle function generates a vector containing the triangle window. The length of the required window is specified by the parameter N, and the stride parameter a is used to space the window values within the output vector w. The length of the output vector should therefore be N*a. Refer to the Bartlett window (described on page 2-134) regarding the relationship between it and the triangle window. Algorithm For even n, the following equation applies. 2n + 1 ------------------ N wn = - 2n - 1 2N ---------------------------N N n ---2 N n ---2 where: n = {0, 1, 2, ..., N-1} For odd n, the following equation applies. 2-150 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library 2n + 2 - ------------------ N+1 wn = - 2n 2N ------------------N+1 N n ---2 N n ---2 where: n = {0, 1, 2, ..., N-1} Domain a > 0; N > 0 Error Conditions None. See Also gen_bartlett, gen_blackman,gen_gaussian, gen_hamming, gen_hanning, gen_harris, gen_kaiser, gen_rectangular, gen_vonhann CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-151 Documented Library Functions gen_vonhann Generate von Hann window Synopsis #include void gen_vonhann (float dm w[], int a, int N); Description The gen_vonhann function is identical to gen_hanning window (described on page 2-142). Error Conditions None. See Also gen_hanning 2-152 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library histogram Histogram Synopsis #include int *histogram (int out[], const int in[], int out_len, int samples, int bin_size); Description The histogram function computes a scaled-integer histogram of its input array. The bin_size parameter is used to adjust the width of each individual bin in the output array. For example, a bin_size of 5 indicates that the first location of the output array holds the number of occurrences of a 0, 1, 2, 3, or 4. The output array is first zeroed by the function, then each sample in the input array is multiplied by 1/bin_size and truncated. The appropriate bin in the output array is incremented. This function returns a pointer to the output array. For maximal performance, this function does not perform out-of-bounds checking. Therefore, all values within the input array must be within range (that is, between 0 and bin_size * out_len). Error Conditions None. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-153 Documented Library Functions Example #include #define SAMPLES 1024 int length = 2048; int excitation[SAMPLES], response[2048]; histogram (response, excitation, length, SAMPLES, 5); See Also mean, var 2-154 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library ifft Inverse complex radix-2 Fast Fourier Transform Synopsis #include complex_float *ifft (complex_float complex_float dm input[], dm temp[], complex_float dm output[], const complex_float pm twiddle[], int twiddle_stride, int n ); Description The ifft function transforms the frequency domain complex input signal sequence to the time domain by using the radix-2 Fast Fourier Transform (FFT). The size of the input array input, the output array output, and the temporary working buffer temp must be at least n, where n represents the number of points in the FFT; n must be a power of 2 and no smaller than 8. If the input data can be overwritten, memory can be saved by setting the pointer of the temporary array explicitly to the input array, or to NULL. (In either case the input array will also be used as the temporary working array.) The minimal size of the twiddle table must be n/2. A larger twiddle table may be used provided that the value of the twiddle table stride argument twiddle_stride is set appropriately. If the size of the twiddle table is x, then twiddle_stride must be set to (2*x)/n. The library function twidfft (on page 2-220) can be used to compute the required twiddle table. The coefficients generated are positive cosine coefficients for the real part and negative sine for the imaginary part. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-155 Documented Library Functions library also contains the ifftf function (see ifftf), which is an The optimized implementation of an inverse complex FFT using a fast radix-2 algorithm. The ifftf function, however, imposes certain memory alignment requirements that may not be appropriate for some applications. The function returns the address of the output array. Algorithm The following equation is the basis of the algorithm. 1 x n = ---- N N-1 - nk X k W N k=0 Error Conditions None. Example #include #define N_FFT 64 complex_float input[N_FFT]; complex_float output[N_FFT]; complex_float temp[N_FFT]; int twiddle_stride = 1; complex_float pm twiddle[N_FFT/2]; 2-156 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library /* Populate twiddle table */ twidfft(twiddle, N_FFT); /* Compute Fast Fourier Transform */ ifft(input, temp, output, twiddle, twiddle_stride, N_FFT); See Also cfft, ifftf, ifftN, rfft, twidfft ifft function uses SIMD by default. Refer to Implications of The Using SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-157 Documented Library Functions ifftf fast inverse complex radix-2 Fast Fourier Transform Synopsis #include void ifftf (float data_real[], float data_imag[], float temp_real[], float temp_imag[], const float twid_real[], const float twid_imag[], int n); Description The ifftf function transforms the frequency domain complex input signal sequence to the time domain by using the accelerated version of the Discrete Fourier Transform known as a Fast Fourier Transform or FFT. It decimates in frequency, using an optimized radix-2 algorithm. The array data_real contains the real part of a complex input signal, and the array data_imag contains the imaginary part of the signal. On output, the function overwrites the data in these arrays and stores the real part of the inverse FFT in data_real, and the imaginary part of the inverse FFT in data_imag. If the input data is to be preserved, it must first be copied to a safe location before calling this function. The argument n represents the number of points in the inverse FFT. It must be a power of 2 and must be at least 64. The ifftf function has been designed for optimal performance and requires that the arrays data_real and data_imag are aligned on an address boundary that is a multiple of the FFT size. For certain applications, this alignment constraint may not be appropriate; in such cases, the application should call the ifft function instead with no loss of facility (apart from performance). 2-158 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library The arrays temp_real and temp_imag are used as intermediate temporary buffers and should each be of size n. The twiddle table is passed in using the arrays twid_real and twid_imag. The array twid_real contains the positive cosine factors, and the array twid_imag contains the negative sine factors. Each array should be of size n/2. The twidfftf function (on page 2-223) may be used to initialize the twiddle table arrays. It is recommended that the arrays containing real parts (data_real, temp_real, and twid_real) are allocated in separate memory blocks from the arrays containing imaginary parts (data_imag, temp_imag, and twid_imag). Otherwise, the performance of the function degrades. ifftf function has been implemented to make highly efficient The use of the processor's SIMD capabilities and long word addressing mode. The function therefore imposes the following restrictions: * All the arrays that are passed to the function must be allocated in internal memory. The DSP run-time library does not contain a version of the function that can be used with data in external memory. * The function should not be used with any application that relies on the -reserve register[, register...] switch. * Due to the alignment restrictions of the input arrays (as documented above), it is unlikely that the function will generate the correct results if the input arrays are allocated on the stack. For more information, refer to refer to "Implications of Using SIMD Mode" and Using Data in External Memory. Error Conditions None. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-159 Documented Library Functions Example #include #define FFT_SIZE 1024 #pragma align 1024 static float dm input_r[FFT_SIZE]; #pragma align 1024 static float pm input_i[FFT_SIZE]; float dm temp_r[FFT_SIZE]; float pm temp_i[FFT_SIZE]; float dm twid_r[FFT_SIZE/2]; float pm twid_i[FFT_SIZE/2]; twidfftf(twid_r,twid_i,FFT_SIZE); ifftf(input_r,input_i, temp_r,temp_i, twid_r,twid_i,FFT_SIZE); See Also cfftf, ifft, ifftN, rfftf_2, twidfftf 2-160 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library ifftN N-point inverse complex radix-2 Fast Fourier Transform Synopsis #include float *ifft65536 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *ifft32768 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *ifft16384 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *ifft8192 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *ifft4096 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *ifft2048 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *ifft1024 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-161 Documented Library Functions float *ifft512 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *ifft256 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *ifft128 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *ifft64 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *ifft32 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *ifft16 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); float *ifft8 (const float dm real_input[], const float dm imag_input[], float dm real_output[], float dm imag_output[]); Description Each of these ifftN functions computes the N-point radix-2 inverse Fast Fourier Transform (IFFT) of its floating-point input (where N is 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768 or 65536). 2-162 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library There are fourteen distinct functions in this set. All perform the same function with the same type and number of arguments. The only difference between them is the size of the arrays on which they operate. To call a particular function, substitute the number of points for N. For example, ifft8 (r_inp, i_inp, r_outp, i_outp); The input to ifftN are two floating-point arrays of N points. The array real_input contains the real components of the inverse FFT input and the array imag_input contains the imaginary components. If there are fewer than N actual data points, you must pad the arrays with zeros to make N samples. However, better results occur with less zero padding. The input data should be windowed (if necessary) before calling the function because no preprocessing is performed on the data. The time-domain signal generated by the ifftN functions is stored in the arrays real_output and imag_output. The array real_output contains the real component of the complex output signal, and the array imag_output contains the imaginary component. The output is scaled by N, the number of points in the inverse FFT. The functions return a pointer to the real_output array. If the input data can be overwritten, then the ifftN functions allow the array real_input to share the same memory as the array real_output, and imag_input to share the same memory as imag_output. This improves memory usage, but at the cost of run-time performance. library functions have not been optimized for SHARC These SIMD processors. Alternative FFT functions that do exploit this feature are defined in the filter.h header file. Error Conditions None. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-163 Documented Library Functions Example #include #define N 2048 float real_input[N], imag_input[N]; float real_output[N], imag_output[N]; ifft2048 (real_input, imag_input, real_output, imag_output); See Also cfftN, ifft, ifftN, rfftN 2-164 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library ifftN N-point inverse complex radix-2 Fast Fourier Transform Synopsis #include complex_float *ifft65536 (complex_float dm input[], complex_float dm output[]); complex_float *ifft32768 (complex_float dm input[], complex_float dm output[]); complex_float *ifft16384 (complex_float dm input[], complex_float dm output[]); complex_float *ifft8192 (complex_float dm input[], complex_float dm output[]); complex_float *ifft4096 (complex_float dm input[], complex_float dm output[]); complex_float *ifft2048 (complex_float dm input[], complex_float dm output[]); complex_float *ifft1024 (complex_float dm input[], complex_float dm output[]); complex_float *ifft512 (complex_float dm input[], complex_float dm output[]); complex_float *ifft256 (complex_float dm input[], complex_float dm output[]); CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-165 Documented Library Functions complex_float *ifft128 (complex_float input[], complex_float dm output[]); complex_float *ifft64 (complex_float dm input[], complex_float dm output[]); complex_float *ifft32 (complex_float dm input[], complex_float dm output[]); complex_float *ifft16 (complex_float dm input[], complex_float dm output[]); complex_float *ifft8 (complex_float dm input[], complex_float dm output[]); Description These ifftN functions are defined in the header file filter.h; they have been optimized to take advantage of the SIMD capabilities of the SHARC processors. These FFT functions require complex arguments to ensure that the real and imaginary parts are interleaved in memory and are thus accessible in a single cycle, using the wider data bus of the processor. Each of these ifftN functions computes the N-point radix-2 inverse Fast Fourier Transform (IFFT) of its floating-point input (where N is 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, or 65536). There are fourteen distinct functions in this set. All perform the same function with the same type and number of arguments. The only difference between them is the size of the arrays on which they operate. To call a particular function, substitute the number of points for N. For example, ifft8 (input, output); 2-166 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library The input to ifftN is a floating-point array of N points. If there are fewer than N actual data points, you must pad the array with zeros to make N samples. However, better results occur with less zero padding. The input data should be windowed (if necessary) before calling the function because no preprocessing is performed on the data. Optimal memory usage can be achieved by specifying the input array as the output array, but at the cost of run-time performance. The ifftN functions return a pointer to the output array. ifftN functions use the input array as an intermediate work The space. If the input data is to be preserved it must first be copied to a safe location before calling these functions. Error Conditions None. Example #include #define N 2048 complex_float input[N], output[N]; ifft2048 (input, output); See Also cfftN, ifft, ifftf, rfftN these functions use SIMD. Refer to Implications of ByUsingdefault, SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-167 Documented Library Functions iir infinite impulse response (IIR) filter Synopsis (Scalar-Valued Version) #include float iir (float sample, const float pm a_coeffs[], const float pm b_coeffs[], float dm state[], int taps); Synopsis (Vector-Valued Version) #include float *iir (const float dm input[], float dm output[], const float pm coeffs[], float dm state[], int samples, int sections); Description (Scalar-Valued Version) The scalar-valued version of the iir function implements a parallel second-order direct form II infinite impulse response (IIR) filter. The function returns the filtered response of the input data sample. The characteristics of the filter are dependent upon a set of coefficients, a delay line, and the length of the filter. The length of filter is specified by the argument taps. The set of IIR filter coefficients is composed of a-coefficients and b-coefficients. The a0 coefficient is assumed to be 1.0, and the remaining 2-168 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library a-coefficients should be scaled accordingly and stored in the array a_coeffs in reverse order. The length of the a_coeffs array is taps and therefore a_coeffs[0] should contain ataps, and a_coeffs[taps-1] should contain a1. The b-coefficients are stored in the array b_coeffs, also in reverse order. The length of the b_coeffs is taps+1, and so b_coeffs[0] contains btaps and b_coeffs[taps] contains b0. Both the a_coeffs and b_coeffs arrays must be located in Program Memory (PM) so that the single-cycle dual-memory fetch of the processor can be used. Each filter should have its own delay line which the function maintains in the array state. The array should be initialized to zero before calling the function for the first time and should not be modified by the calling program. The length of the state array should be taps+1 as the function uses the array to store a pointer to the current delay line. library function uses the architecture's dual-data move instruc The tion to provide simultaneous access to the filter coefficients (in PM data memory) and the delay line. When running on an ADSP-21367, ADSP-21368 or ADSP-21369 processor, the filter coefficients and the delay line must not both be allocated in external memory; otherwise, the function can generate an incorrect set of results. This occurs because in a dual-data move instruction, the hardware does not support both memory accesses allocated to external memory. Therefore, ensure that the filter coefficients or the delay line (or, optionally, both) are allocated in internal memory when running on one of the ADSP-2136x processors specified above. The flow graph (Figure 2-2) corresponds to the iir() routine as part of the DSP run-time library. The b_coeffs array should equal TAPS +1, while the a_coeffs array should equal TAPS. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-169 Documented Library Functions The biquad function should be used instead of the iir function if a multi-stage filter is required. Sample Output b_coeffs [TAPS - 1] b_coeffs [TAPS - 2] b_coeffs [TAPS - 3] b_coeffs [0] a_coeffs [TAPS - 1] a_coeffs [TAPS - 2] a_coeffs [TAPS - 3] a_coeffs [0] Figure 2-2. Flow Graph 2-170 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Description (Vector-Valued Version) The vector-valued versions of the iir function implement an infinite impulse response (IIR) filter defined by the coefficients and delay line that are supplied in the call to the function. The filter is implemented as a cascaded biquad, and generate the filtered response of the input data input and store the result in the output vector output. The number of input samples and the length of the output vector is specified by the argument samples. The characteristics of the filter are dependent upon the filter coefficients and the number of biquad sections. The number of sections is specified by the argument sections, and the filter coefficients are supplied to the function using the argument coeffs. Each stage has four coefficients which must be ordered in the following form: [a2 stage 1, a1 stage 1, b2 stage 1, b1 stage 1, a2 stage 2, ...] The function assumes that the value of B0 is 1.0, and so the B1 and B2 coefficients should be scaled accordingly. As a consequence of this, all the output generated by the iir function must be scaled by the product of all the B0 coefficients to obtain the correct signal amplitude. The function also assumes that the value of the A0 coefficient is 1.0, and the A1 and A2 coefficients should be normalized. These requirements are demonstrated in the example below. The coeffs array must be allocated in Program Memory (PM) as the function uses the single-cycle dual-memory fetch of the processor. The definition of the coeffs array is therefore: float pm coeffs[4*sections]; CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-171 Documented Library Functions Each filter should have its own delay line which is represented by the array state. The state array should be large enough for two delay elements per biquad section and hold an internal pointer that allows the filter to be restarted. The definition of the state is: float state[2*sections + 1]; The state array should be initially cleared to zero before calling the function for the first time and should not be modified by the user program. The function returns a pointer to the output vector. The vector-valued versions of the iir functions are based on the following algorithm: Hz = sections-1 n=0 bn 2 -2 b n 1 -1 1 + -------- z + -------- z b n 0 b n 0 ----------------------------------------------------------a n 1 -1 a n 2 -2 1 + -------- z + -------- z a n 0 a n 0 To get the correct amplitude of the signal, H(z) should be adjusted by this formula: sections-1 b 0 n H z = H z ------ a n 0 n=0 Error Conditions None. 2-172 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example Scalar-Valued #include #define NSAMPLES 256 #define TAPS 10 float input[NSAMPLES]; float output[NSAMPLES]; float pm a_coeffs[TAPS]; float pm b_coeffs[TAPS+1]; float state[TAPS + 1]; int i; for (i = 0; i < TAPS+1; i++) state[i] = 0; for (i = 0; i < NSAMPLES; i++) output[i] = iir (input[i], a_coeffs, b_coeffs, state, TAPS); Vector-Valued #include #define SAMPLES 100 #define SECTIONS 4 /* Coefficients generated by a filter design tool that uses a direct form II */ const struct { float a0; float a1; CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-173 Documented Library Functions float a2; } A_coeffs[SECTIONS]; const struct { float b0; float b1; float b2; } B_coeffs[SECTIONS]; /* Coefficients for the iir function */ float pm coeffs[4 * SECTIONS]; /* Input, Output, and State Arrays */ float input[SAMPLES], output[SAMPLES]; float state[2*SECTIONS + 1]; float scale; /* used to scale the output from iir */ /* Utility Variables */ float a0,a1,a2; float b0,b1,b2; int i; /* Transform the A-coefficients and B-coefficients from a filter design tool into coefficients for the iir function */ scale = 1.0; for (i = 0; i < SECTIONS; i++) { a0 = A_coeffs[i].a0; a1 = A_coeffs[i].a1; 2-174 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library a2 = A_coeffs[i].a2; coeffs[(i*4) + 0] = (a2/a0); coeffs[(i*4) + 1] = (a1/a0); b0 = B_coeffs[i].b0; b1 = B_coeffs[i].b1; b2 = B_coeffs[i].b2; coeffs[(i*4) + 2] = (b2/b0); coeffs[(i*4) + 3] = (b1/b0); scale = scale * (b0/a0); } /* Call the iir function */ for (i = 0; i <= 2*SECTIONS; i++) state[i] = 0; /* initialize the state array */ iir (input, output, coeffs, state, SAMPLES, SECTIONS); /* Adjust output by all (b0/a0) terms */ for (i = 0; i < SAMPLES; i++) output[i] = output[i] * scale; See Also biquad, fir CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-175 Documented Library Functions matinv Real matrix inversion Synopsis #include float *matinvf (float dm *output, const float dm *input, int samples); double *matinv (double dm *output, const double dm *input, int samples); long double *matinvd (long double dm *output, const long double dm *input, int samples); Description The matinv functions employ Gauss-Jordan elimination with full pivoting to compute the inverse of the input matrix input and store the result in the matrix output. The dimensions of the matrices input and output are [samples][samples]. The functions return a pointer to the output matrix. Error Conditions If no inverse exists for the input matrix, the functions return a null pointer. 2-176 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define N 8 double a[N][N]; double a_inv[N][N]; matinv ((double *)(a_inv),(double *)(a),N); See Also No related functions. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-177 Documented Library Functions matmadd Real matrix + matrix addition Synopsis #include float *matmaddf (float dm *output, const float dm *a, const float dm *b, int rows, int cols); double *matmadd (double dm *output, const double dm *a, const double dm *b, int rows, int cols); long double *matmaddd (long double dm *output, const long double dm *a, const long double dm *b, int rows, int cols); Description The matmadd functions perform a matrix addition of the input matrices a[][] and b[][], and return the result in the matrix output[][]. The dimensions of these matrices are a[rows][cols], b[rows][cols], and output[rows][cols]. The functions return a pointer to the output matrix. Error Conditions None. 2-178 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define ROWS 4 #define COLS 8 double input_1[ROWS][COLS], *a_p = (double *) (&input_1); double input_2[ROWS][COLS], *b_p = (double *) (&input_2); double result[ROWS][COLS], *res_p = (double *) (&result); matmadd (res_p, a_p, b_p, ROWS, COLS); See Also cmatmadd, matmmlt, matmsub, matsadd function (and , if are the same size asThe matmaddf ) uses SIMD by default. Refer to Implications of Using matmadd doubles floats SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-179 Documented Library Functions matmmlt Real matrix * matrix multiplication Synopsis #include float *matmmltf (float dm *output, const float dm *a, const float dm *b, int a_rows, int a_cols, b_cols); double *matmmlt (double dm *output, const double dm *a, const double dm *b, int a_rows, int a_cols, b_cols); long double *matmmltd (long double dm *output, const long double dm *a, const long double dm *b, int a_rows, int a_cols, b_cols); Description The matmmlt functions perform a matrix multiplication of the input matrices a[][] and b[][], and return the result in the matrix output[][]. The dimensions of these matrices are a[a_rows][a_cols], b[a_cols][b_cols], and output[a_rows][b_cols]. The functions return a pointer to the output matrix. 2-180 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Algorithm The following equation is the basis of the algorithm. a_cols - 1 c i j = a i l b l j l=0 where: i = {0,1,2,...,a_rows-1} j = {0,1,2,...,b_cols-1} Error Conditions None. Example #include #define ROWS_1 4 #define COLS_1 8 #define COLS_2 2 double input_1[ROWS_1][COLS_1], *a_p = (double *) (&input_1); double input_2[COLS_1][COLS_2], *b_p = (double *) (&input_2); double result[ROWS_1][COLS_2], *res_p = (double *) (&result); matmmlt (res_p, a_p, b_p, ROWS_1, COLS_1, COLS_2); See Also cmatmmlt, matmadd, matmsub, matsmlt CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-181 Documented Library Functions matmsub Real matrix - matrix subtraction Synopsis #include float *matmsubf (float dm *output, const float dm *a, const float dm *b, int rows, int cols); double *matmsub (double dm *output, const double dm *a, const double dm *b, int rows, int cols); long double *matmsubd (long double dm *output, const long double dm *a, const long double dm *b, int rows, int cols); Description The matmsub functions perform a matrix subtraction of the input matrices a[][] and b[][], and return the result in the matrix output[][]. The dimensions of these matrices are a[rows][cols], b[rows][cols], and output[rows][cols]. The functions return a pointer to the output matrix. Error Conditions None. 2-182 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define ROWS 4 #define COLS 8 double input_1[ROWS][COLS], *a_p = (double *) (&input_1); double input_2[ROWS][COLS], *b_p = (double *) (&input_2); double result[ROWS][COLS], *res_p = (double *) (&result); matmsub (res_p, a_p, b_p, ROWS, COLS); See Also cmatmsub, matmadd, matmmlt, matssub function (and , if are the same size asThe matmsubf ) uses SIMD by default. Refer to Implications of Using matmsub doubles floats SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-183 Documented Library Functions matsadd Real matrix + scalar addition Synopsis #include float *matsaddf (float dm *output, const float dm *a, float scalar, int rows, int cols); double *matsadd (double dm *output, const double dm *a double scalar, int rows, int cols); long double *matsaddd (long double dm *output, const long double dm *a, long double scalar, int rows, int cols); Description The matsadd functions add a scalar to each element of the input matrix a[][], and return the result in the matrix output[][]. The dimensions of these matrices are a[rows][cols] and output[rows][cols]. The functions return a pointer to the output matrix. Error Conditions None. 2-184 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define ROWS 4 #define COLS 8 double input[ROWS][COLS], *a_p = (double *) (&input); double result[ROWS][COLS], *res_p = (double *) (&result); double x; matsadd (res_p, a_p, x, ROWS, COLS); See Also cmatsadd, matmadd, matsmlt, matssub matsaddf function (and , if are the same size The ) uses SIMD by default. Refer to Implications of Using as matsadd doubles floats SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-185 Documented Library Functions matsmlt Real matrix * scalar multiplication Synopsis #include float *matsmltf (float dm *output, const float dm *a, float scalar, int rows, int cols); double *matsmlt (double dm *output, const double dm *a double scalar, int rows, int cols); long double *matsmltd (long double dm *output, const long double dm *a, long double scalar, int rows, int cols); Description The matsmlt functions multiply a scalar with each element of the input matrix a[][], and return the result in the matrix output[][]. The dimensions of these matrices are a[rows][cols] and output[rows][cols]. The functions return a pointer to the output matrix. Error Conditions None. 2-186 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define ROWS 4 #define COLS 8 double input[ROWS][COLS], *a_p = (double *) (&input); double result[ROWS][COLS], *res_p = (double *) (&result); double x; matsmlt (res_p, a_p, x, ROWS, COLS); See Also cmatsmlt, matmmlt, matsadd, matssub function (and , if are the same size asThe matsmltf ) uses SIMD by default. Refer to Implications of Using matsmlt doubles floats SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-187 Documented Library Functions matssub Real matrix - scalar subtraction Synopsis #include float *matssubf (float dm *output, const float dm *a, float scalar, int rows, int cols); double *matssub (double dm *output, const double dm *a double scalar, int rows, int cols); long double *matssubd (long double dm *output, const long double dm *a, long double scalar, int rows, int cols); Description The matssub functions subtract a scalar from each element of the input matrix a[][], and return the result in the matrix output[][]. The dimensions of these matrices are a[rows][cols] and output[rows][cols]. The functions return a pointer to the output matrix. Error Conditions None. 2-188 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define ROWS 4 #define COLS 8 double input[ROWS][COLS], *a_p = (double *) (&input); double result[ROWS][COLS], *res_p = (double *) (&result); double x; matssub (res_p, a_p, x, ROWS, COLS); See Also cmatssub, matmsub, matsadd, matsmlt function (and , if are the same size asThe matssubf ) uses SIMD by default. Refer to Implications of Using matssub doubles floats SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-189 Documented Library Functions mean Mean Synopsis #include float meanf (const float in[], int length); double mean (const double in[], int length); long double meand (const long double in[], int length); Description The mean functions return the mean of the input array in[]. The length of the input array is length. Error Conditions None. Example #include #define SIZE 256 double data[SIZE]; double result; result = mean (data, SIZE); See Also var function (and , if are the same size as The meanf ) uses SIMD by default. Refer to Implications of Using mean doubles floats SIMD Mode for more information. 2-190 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library mu_compress -law compression Synopsis (Scalar-Valued) #include int mu_compress (int x); Synopsis (Vector-Valued) #include int *mu_compress(const int dm input[], int dm output[], int length); Description The mu_compress functions take linear 14-bit speech samples and compress them according to ITU recommendation G.711 (-law definition). The scalar version of mu_compress inputs a single data sample and returns an 8-bit compressed output sample. The vector versions of mu_compress take the array input, and return the compressed 8-bit samples in the vector output. The parameter length defines the size of both the input and output vectors. The functions return a pointer to the output array. The vector versions of uses serial port 0 to perform the companding on an ADSP-21160 processor; therefore, serial mu_compress port 0 must not be in use when this routine is called. The serial port is not used by this function on any other ADSP-21xxx SIMD architectures. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-191 Documented Library Functions Error Conditions None. Example Scalar-Valued #include int sample, compress; compress = mu_compress (sample); Vector-Valued #include #define NSAMPLES 50 int data [NSAMPLES], compressed[NSAMPLES]; mu_compress (data, compressed, NSAMPLES); See Also a_compress, mu_expand 2-192 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library mu_expand -law expansion Synopsis (Scalar-Valued) #include int mu_expand (int x); Synopsis (Vector-Valued) #include int *mu_expand(const int dm input[], int dm output[], int length); Description The mu_expand functions take 8-bit compressed speech samples and expand them according to ITU recommendation G.711 (-law definition). The scalar version of mu_expand inputs a single data sample and returns a linear 14-bit signed sample. The vector version of mu_expand takes an array of 8-bit compressed speech samples and expands it according to ITU recommendation G.711 (-law definition). The array returned contains linear 14-bit signed samples. These functions returns a pointer to the output data array. The vector versions of uses serial port 0 to perform the companding on an ADSP-21160 processor. Therefore, serial port 0 mu_expand must not be in use when this routine is called. The serial port is not used by this function on any other ADSP-21xxx SIMD architectures. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-193 Documented Library Functions Error Conditions None. Example Scalar-Valued #include int compressed_sample, expanded; expanded = mu_expand (compressed_sample); Vector-Valued #include #define NSAMPLES 50 int data [NSAMPLES]; int expanded_data[NSAMPLES]; mu_expand (data, expanded_data, NSAMPLES); See Also a_expand, mu_compress 2-194 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library norm Normalization Synopsis #include complex_float normf (complex_float a); complex_double norm (complex_double a); complex_long_double normd(complex_long_double a); Description The normalization functions normalize the complex input a and return the result. Algorithm The following equations are the basis of the algorithm. Re a Re c = -------------------------------------------Re 2 a + Im 2 a Im a Im c = -------------------------------------------Re 2 a + Im 2 a Error Conditions The normalization functions return zero if cabs(a) is equal to zero. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-195 Documented Library Functions Example #include complex_double x = {2.0,-4.0}; complex_double z; z = norm(x); /* z = (0.4472,-0.8944) */ See Also No related functions. 2-196 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library polar Construct from polar coordinates Synopsis #include complex_float polarf (float mag, float phase); complex_double polar (double mag, double phase); complex_long_double polard (long double mag,long double phase); Description These functions transform the polar coordinate, specified by the arguments mag and phase, into a Cartesian coordinate and return the result as a complex number in which the x-axis is represented by the real part, and the y-axis by the imaginary part. The phase argument is interpreted as radians. Algorithm The algorithm for transforming a polar coordinate into a Cartesian coordinate is: Re(c) = mag * cos(phase) Im(c) = mag * sin(phase) Error Conditions The input argument phase for polarf must be in the domain [-1.647e6, 1.647e6] and for polard must be in the domain [-8.433e8, 8.433e8]. The functions return a complex value of zero if the specified phase is outside their domain. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-197 Documented Library Functions Example #include #define PI 3.14159265 float magnitude = 2.0; float phase = PI; complex_float z; z = polarf (magnitude,phase); /* z.re = -2.0, z.im = 0.0 */ See Also arg, cartesian 2-198 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library rfft Real radix-2 Fast Fourier Transform Synopsis #include complex_float *rfft (float dm input[], float dm temp[], complex_float dm output[], const complex_float pm twiddle[], int twiddle_stride, int n); Description The rfft function transforms the time domain real input signal sequence to the frequency domain by using the radix-2 Fast Fourier Transform (FFT). The size of the input array input and the temporary working buffer temp must be at least n, where n represents the number of points in the FFT; n must be a power of 2 and no smaller than 16. If the input data can be overwritten, memory can be saved by setting the pointer of the temporary array explicitly to the input array or to NULL. (In either case the input array will also be used as a temporary working array.) As the complex spectrum of a real FFT is symmetrical about the midpoint, the rfft function will only generate the first (n/2)+1 points of the FFT, and so the size of the output array output must be at least of length (n/2) + 1. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-199 Documented Library Functions After returning from the rfft function, the output array will contain the following values: * DC component of the signal in output[0].re (output[0].im = 0) * First half of the complex spectrum in output[1]... output[(n/2)-1] * Nyquist frequency in output[n/2].re (output[n/2].im = 0) Refer to the Example section below to see how an application would construct the full complex spectrum, using the symmetry of a real FFT. The minimal size of the twiddle table must be n/2. A larger twiddle table may be used, providing that the value of the twiddle table stride argument twiddle_stride is set appropriately. If the size of the twiddle table is x, then twiddle_stride must be set to (2*x)/n. The library function twidfft (on page 2-220) can be used to compute the required twiddle table. The coefficients generated are positive cosine coefficients for the real part and negative sine coefficients for the imaginary part. library also contains the rfftf_2 function. (For more informa The tion, see rfftf_2.) This function is an optimized implementation of a real FFT using a fast radix-2 algorithm, capable of computing two real FFTs in parallel. The rfftf_2 function, however, imposes certain memory alignment requirements that may not be appropriate for some applications. The function returns the address of the output array. Algorithm The following equation is the basis of the algorithm. 2-200 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Xk = N-1 nk x n WN n=0 Error Conditions None. Example #include #include #define FFTSIZE 32 float sigdata[FFTSIZE]; /* input signal */ complex_float r_output[FFTSIZE]; /* FFT of input signal */ complex_float i_output[FFTSIZE]; /* inverse of r_output */ complex_float i_temp[FFTSIZE]; complex_float c_temp[FFTSIZE]; float *r_temp = (float *) c_temp; complex_float pm twiddle_table[FFTSIZE/2]; int i; /* Initialize the twiddle table */ CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-201 Documented Library Functions twidfft (twiddle_table,FFTSIZE); /* Calculate the FFT of a real signal */ rfft (sigdata,r_temp,r_output,twiddle_table,1,FFTSIZE); /* (rfft sets r_output[FFTSIZE/2] to the Nyquist) */ /* Add the 2nd half of the spectrum */ for (i = 1; i < (FFTSIZE/2); i++) { r_output[FFTSIZE - i] = conjf (r_output[i]); } /* Calculate the inverse of the FFT */ ifft (r_output,i_temp,i_output,twiddle_table,1,FFTSIZE); See Also cfft, fft_magnitude, ifft, rfftf_2, rfftN, twidfft 2-202 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library rfft_mag rfft magnitude Synopsis #include float *rfft_mag (complex_float dm input[], float dm output[], int fftsize); float *fft_mag (complex_float dm input[], float dm output[], int fftsize); Description The rfft_mag function computes a normalized power spectrum from the output signal generated by a rfftN function. The size of the signal and the size of the power spectrum is fftsize/2. The function returns a pointer to the output matrix. The fft_mag function is equivalent to the rfft_mag function and is provided for compatibility with previous versions of CCES. using the rfft_mag function, note that the generated power When spectrum will not contain the Nyquist frequency. In cases where the Nyquist frequency is required, the fft_magnitude function must be used in conjunction with the rfft function. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-203 Documented Library Functions Algorithm The algorithm used to calculate the normalized power spectrum is: 2 2 2 Re a z + Im a z magnitude z = ---------------------------------------------------------------fftsize Error Conditions None. Example #include #define N 64 float fft_input[N]; complex_float fft_output[N/2]; float spectrum[N/2]; rfft64 (fft_input, fft_output); rfft_mag (fft_output, spectrum, N); See Also cfft_mag, fft_magnitude, fftf_magnitude, rfftN this function uses SIMD. Refer to Implications of ByUsingdefault, SIMD Mode for more information. 2-204 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library rfftf_2 Fast parallel real radix-2 Fast Fourier Transform Synopsis #include void rfftf_2 (float data_one_real[], float data_one_imag[], float data_two_real[], float data_two_imag[], const float twid_real[], const float twid_imag[], int n); Description The rfftf_2 function computes two n-point real radix-2 Fast Fourier Transforms (FFT) using a decimation-in-frequency algorithm. The FFT size n must be a power of 2 and not less than 64. The array data_one_real contains the input to the first real FFT, while data_two_real contains the input to the second real FFT. Both arrays are expected to be of length n. For optimal performance, the arrays should be located in different memory segments. Furthermore, the two input arrays have to be aligned on an address boundary that is a multiple of the FFT size n. The arrays data_one_imag and data_two_imag of length n are used as temporary workspace. At return, they contain the imaginary part of the respective output data set. The arrays should be located in different memory segments. The size of the twiddle table pointed to by twid_real and twid_imag must be of size n/2. The library function twidfftf (on page 2-223) can be used to compute the required twiddle table. The coefficients generated are positive cosine coefficients for the real part and negative sine coefficients for the imaginary part. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-205 Documented Library Functions function invokes the cfftf function, which has been imple The mented to make highly efficient use of the processor's SIMD capabilities and long word addressing mode. The rfftf_2 function therefore imposes the following restrictions: * All the arrays that are passed to the function must be allocated in internal memory. The DSP run-time library does not contain a version of the function that can be used with data in external memory. * Do not use the function with any application that relies on the -reserve register[, register...] switch. * Due to the alignment restrictions of the input arrays (as documented above), it is unlikely that the function will generate the correct results if the input arrays are allocated on the stack. For more information, refer to refer to Implications of Using SIMD Mode and Using Data in External Memory. Error Conditions None. Example #include #define FFT_SIZE 64 float dm twidtab_re[FFT_SIZE/2]; float pm twidtab_im[FFT_SIZE/2]; #pragma align 64 static float dm fft1_re[FFT_SIZE]; static float pm fft1_im[FFT_SIZE]; 2-206 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library #pragma align 64 static float dm fft2_re[FFT_SIZE]; static float pm fft2_im[FFT_SIZE]; twidfftf (twidtab_re, twidtab_im, FFT_SIZE); rfftf_2(fft1_re, fft1_im, fft2_re, fft2_im, twidtab_re, twidtab_im, FFT_SIZE); See Also cfftf, fftf_magnitude, ifftf, rfft, rfftN, twidfftf CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-207 Documented Library Functions rfftN N-point real radix-2 Fast Fourier Transform Synopsis #include float *rfft65536 (const float dm real_input[], float dm real_output[], float dm imag_output[]); float *rfft32768 (const float dm real_input[], float dm real_output[], float dm imag_output[]); float *rfft16384 (const float dm real_input[], float dm real_output[], float dm imag_output[]); float *rfft8192 (const float dm real_input[], float dm real_output[], float dm imag_output[]); float *rfft4096 (const float dm real_input[], float dm real_output[], float dm imag_output[]); float *rfft2048 (const float dm real_input[], float dm real_output[], float dm imag_output[]); float *rfft1024 (const float dm real_input[], float dm real_output[], float dm imag_output[]); float *rfft512 (const float dm real_input[], float dm real_output[], float dm imag_output[]); float *rfft256 (const float dm real_input[], float dm real_output[], float dm imag_output[]); 2-208 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library float *rfft128 (const float dm real_input[], float dm real_output[], float dm imag_output[]); float *rfft64 (const float dm real_input[], float dm real_output[], float dm imag_output[]); float *rfft32 (const float dm real_input[], float dm real_output[], float dm imag_output[]); float *rfft16 (const float dm real_input[], float dm real_output[], float dm imag_output[]); float *rfft8 (const float dm real_input[], float dm real_output[], float dm imag_output[]); Description Each of these rfftN functions are similar to the cfftN functions, except that they only take real inputs. They compute the N-point radix-2 Fast Fourier Transform (RFFT) of their floating-point input (where N is 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, or 65536). There are fourteen distinct functions in this set. All perform the same function with same type and number of arguments. Their only difference is the size of the arrays on which they operate. Call a particular function by substituting the number of points for N. For example, ft8 (r_inp, r_outp, i_outp); The input to rfftN is a floating-point array of N points. If there are fewer than N actual data points, you must pad the array with zeros to make N samples. However, better results occur with less zero padding. The input CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-209 Documented Library Functions data should be windowed (if necessary) before calling the function because no preprocessing is performed on the data. If the input data can be overwritten, then the rfftN functions allow the array real_input to share the same memory as the array imag_output. This improves memory usage with only a minimal run-time penalty. The rfftN functions return a pointer to the real_output array. library functions have not been optimized for SHARC These SIMD processors. Alternative FFT functions that do exploit this feature are defined in the filter.h header file. Error Conditions None. Example #include #define N 2048 float real_input[N]; float real_output[N], imag_output[N]; rfft2048 (real_input, real_output, imag_output); See Also cfftN, fft_magnitude, ifftN, rfft, rfftN 2-210 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library rfftN N-point real radix-2 Fast Fourier Transform Synopsis #include complex_float *rfft65536 (float dm input[], complex_float dm output[]); complex_float *rfft32768 (float dm input[], complex_float dm output[]); complex_float *rfft16384 (float dm input[], complex_float dm output[]); complex_float *rfft8192 (float dm input[], complex_float dm output[]); complex_float *rfft4096 (float dm input[], complex_float dm output[]); complex_float *rfft2048 (float dm input[], complex_float dm output[]); complex_float *rfft1024 (float dm input[], complex_float dm output[]); complex_float *rfft512 (float dm input[], complex_float dm output[]); complex_float *rfft256 (float dm input[], complex_float dm output[]); CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-211 Documented Library Functions complex_float *rfft128 (float dm input[], complex_float dm output[]); complex_float *rfft64 (float dm input[], complex_float dm output[]); complex_float *rfft32 (float dm input[], complex_float dm output[]); complex_float *rfft16 (float dm input[], complex_float dm output[]); Description The rfftN functions are defined in the header file filter.h. They have been optimized to take advantage of the SIMD capabilities of the SHARC processors. These FFT functions require complex arguments to ensure that the real and imaginary parts are interleaved in memory and are therefore accessible in a single cycle using the wider data bus of the processor. Each of these rfftN functions are similar to the cfftN functions except that they only take real inputs. They compute the N-point radix-2 Fast Fourier Transform (RFFT) of their floating-point input (where N is 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, or 65536). There are thirteen distinct functions in this set. All perform the same function with the same type and number of arguments. The only difference between them is the size of the arrays on which they operate. Call a particular function by substituting the number of points for N, as in the following example: rfft16 (input, output); The input to rfftN is a floating-point array of N points. If there are fewer than N actual data points, you must pad the array with zeros to make N samples. However, better results occur with less zero padding. The input 2-212 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library data should be windowed (if necessary) before calling the function because no preprocessing is performed on the data. The rfftN functions will use the input array as an intermediate workspace. If the input data is to be preserved, the input array must be first copied to a safe location. The complex frequency domain signal generated by the rfftN functions is stored in the array output. Because the output signal is symmetric around the midpoint of the frequency domain, the functions only generate N/2 output points. rfftN functions do not calculate the Nyquist frequency (which The would normally located at ). The rfft or cfftN funcoutput[N/2] tions should be used in place of these functions if the Nyquist frequency is required. The rfftN functions return a pointer to the output array. Error Conditions None. Example #include #define N 2048 float input[N]; complex_float output[N/2]; rfft2048 (input, output); CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-213 Documented Library Functions See Also cfftN, ifftN, rfft, rfftN, rfftf_2 these functions use SIMD. Refer to Implications of ByUsingdefault, SIMD Mode for more information. 2-214 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library rms root mean square Synopsis #include float rmsf (const float samples[], int sample_length); double rms (const double samples[], int sample_length); long double rmsd (const long double samples[], int sample_length); Description The root mean square functions return the root mean square of the elements within the input array samples[]. The length of the input array is sample_length. Algorithm The following equation is the basis of the algorithm. n-1 ai 2 i=0 c = ----------------n where: a = samples n = sample_length CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-215 Documented Library Functions Error Conditions None. Example #include #define SIZE 256 double data[SIZE]; double result; result = rms (data, SIZE); See Also mean, var The rmsf function (and , if are the same size as ) uses SIMD by default. Refer to Implications of Using SIMD Mode rms doubles floats for more information. 2-216 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library rsqrt Reciprocal square root Synopsis #include float rsqrtf (float x); double rsqrt (double x); long double rsqrtd (long double x); Description The rsqrt functions return the reciprocal positive square root of their argument. Error Conditions The rsqrt functions return zero for a negative input. Example #include double y; y = rsqrt (2.0); /* y = 0.707 */ See Also sqrt CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-217 Documented Library Functions transpm matrix transpose Synopsis #include float *transpmf (float dm *output, const float dm *a, int rows, int cols); double *transpm (double dm *output, const double dm *a, int rows, int cols); long double *transpmd (long double dm *output, const long double dm *a, int rows, int cols); Description The transpm functions compute the linear algebraic transpose of the input matrix a[][], and return the result in the matrix output[][]. The dimensions of these matrices are a[rows][cols], and output[cols][rows]. The functions return a pointer to the output matrix. Algorithm The algorithm for the linear algebraic transpose of a matrix is defined as: cji = aij Error Conditions None. 2-218 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define ROWS 4 #define COLS 8 float a[ROWS][COLS]; float a_transpose[COLS][ROWS]; transpmf ((float *)(a_transpose),(float *)(a), ROWS, COLS); See Also No related functions. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-219 Documented Library Functions twidfft Generate FFT twiddle factors Synopsis #include complex_float *twidfft(complex_float pm twiddle_tab[], int fftsize); Description The twidfft function calculates complex twiddle coefficients for an FFT of size fftsize and returns the coefficients in the vector twiddle_tab. The vector is known as a twiddle table; it contains pairs of cosine and sine values and is used by an FFT function to calculate a Fast Fourier Transform. The table generated by this function may be used by any of the FFT functions cfft, ifft, and rfft. A twiddle table of a given size will contain constant values. Typically, such a table is generated only once during the development cycle of an application and is thereafter preserved by the application in some suitable form. An application that computes FFTs of different sizes does not require multiple twiddle tables. A single twiddle table can be used to calculate the FFT's, provided that the table is created for the largest FFT that the application expects to generate. Each of the FFT functions cfft, ifft, and rfft have a twiddle stride argument that the application would set to 1 when it is generating an FFT with the largest number of data points. To generate an FFT with half the number of these points, the application would call the FFT functions with the twiddle stride argument set to 2; to generate an FFT with a quarter of the largest number of points, it would set the twiddle stride to 4, and so on. The function returns a pointer to twiddle_tab. 2-220 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Algorithm This function takes FFT length fft_size as an input parameter and generates the lookup table of complex twiddle coefficients. The samples are: 2 twid_re(k) = cos ------ k n 2 twid_im(k) = - sin ------ k n where: n = fft_size k = {0, 1, 2, ..., n/2-1} Error Conditions None. Example #include #define N_FFT #define N_FFT2 128 32 complex_float in1[N_FFT]; complex_float out1[N_FFT]; complex_float in2[N_FFT2]; complex_float out2[N_FFT2]; complex_float temp[N_FFT]; CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-221 Documented Library Functions complex_float pm twid_tab[N_FFT / 2]; twidfft (twid_tab, N_FFT); cfft (in1, temp, out1, twid_tab, 1, N_FFT); cfft (in2, temp, out2, twid_tab, (N_FFT / N_FFT2) /* twiddle stride 4 */, N_FFT2 ); See Also cfft, ifft, rfft, twidfftf 2-222 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library twidfftf Generate FFT twiddle factors for a fast FFT Synopsis #include void twidfftf(float twid_real[], float twid_imag[], int fftsize); Description The twidfftf function generates complex twiddle factors for one of the FFT functions cfftf, ifftf, or rfftf_2. The generated twiddle factors are sets of positive cosine coefficients and negative sine coefficients that the FFT functions will use to calculate the FFT. The function will store the cosine coefficients in the vector twid_real and the sine coefficients in the vector twid_imag. The size of both the vectors should be fftsize/2, where fftsize represents the size of the FFT and must be a power of 2 and at least 64. maximal efficiency, the cfftf, ifftf, and rfftf_2 functions require For and are allocated in separate that the vectors twid_real twid_imag memory blocks. The twiddle factors that are generated for a specific size of FFT are constant values. Typically, the factors are generated only once during the development cycle of an application and are thereafter preserved by the application in some suitable form. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-223 Documented Library Functions Algorithm This function takes FFT length fft_size as an input parameter and generates the lookup table of complex twiddle coefficients. The samples are: 2 twid_re(k) = cos ------ k n 2 twid_im(k) = - sin ------ k n where: n = fft_size k = {0, 1, 2, ..., n/2-1} Error Conditions None. Example #include #define FFT_SIZE 1024 #pragma section("seg_dmdata"); float twid_r[FFT_SIZE/2]; #pragma section("seg_pmdata") 2-224 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library float twid_i[FFT_SIZE/2]; #pragma align 1024 #pragma section("seg_dmdata") float input_r[FFT_SIZE]; #pragma align 1024 #pragma section("seg_pmdata") float input_i[FFT_SIZE]; #pragma section("seg_dmdata") float temp_r[FFT_SIZE]; #pragma section("seg_pmdata") float temp_i[FFT_SIZE]; twidfftf(twid_r,twid_i,FFT_SIZE); cfftf(input_r,input_i, temp_r,temp_i, twid_r,twid_i,FFT_SIZE); See Also cfftf, ifftf, rfftf_2, twidfft CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-225 Documented Library Functions var Variance Synopsis #include float varf (const float a[], int n); double var (const double a[], int n); long double vard (const long double a[], int n); Description The variance functions return the variance of the input array a[]. The length of the input array is n. Algorithm The following equation is the basis of the algorithm. 2 n-1 2 n a i - a 1 i=0 i=0 c = ----------------------------------------------nn - 1 n-1 Error Conditions None. 2-226 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define SIZE 256 double data[SIZE]; double result; result = var (data, SIZE); See Also mean The varf function (and , if are the same size as ) uses SIMD by default. Refer to Implications of Using SIMD Mode var doubles floats for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-227 Documented Library Functions vecdot Vector dot product Synopsis #include float vecdotf (const float dm a[], const float dm b[], int samples); double vecdot (const double dm a[], const double dm b[], int samples); long double vecdotd (const long double dm a[], const long double dm b[], int samples); Description The vecdot functions compute the dot product of the vectors a[] and b[], which are samples in size. They return the scalar result. Algorithm The following equation is the basis of the algorithm. samples - 1 return = ai bi i=0 Error Conditions None. 2-228 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define N 100 double x[N], y[N]; double answer; answer = vecdot (x, y, N); See Also cvecdot function (and , if are the same size as The vecdotf ) uses SIMD by default. Refer to Implications of Using vecdot doubles floats SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-229 Documented Library Functions vecsadd Vector + scalar addition Synopsis #include float *vecsaddf (const float dm a[], float scalar, float dm output[], int samples); double *vecsadd (const double dm a[], double scalar, double dm output[], int samples); long double *vecsaddd (const long double dm a[], long double scalar, long double dm output[], int samples); Description The vecsadd functions compute the sum of each element of the vector a[], added to the scalar. Both the input and output vectors are samples in size. The functions return a pointer to the output vector. Error Conditions None. 2-230 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define N 100 double input[N], result[N]; double x; vecsadd (input, x, result, N); See Also cvecsadd, vecsmlt, vecssub, vecvadd function (and , if are the same size as The vecsaddf ) uses SIMD by default. Refer to Implications of Using vecsadd doubles floats SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-231 Documented Library Functions vecsmlt Vector * scalar multiplication Synopsis #include float *vecsmltf (const float dm a[], float scalar, float dm output[], int samples); double *vecsmlt (const double dm a[], double scalar, double dm output[], int samples); long double *vecsmltd (const long double dm a[], long double scalar, long double dm output[], int samples); Description The vecsmlt functions compute the product of each element of the vector a[], multiplied by the scalar. Both the input and output vectors are samples in size. The functions return a pointer to the output vector. Error Conditions None. 2-232 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define N 100 double input[N], result[N]; double x; vecsmlt (input, x, result, N); See Also cvecsmlt, vecsadd, vecssub, vecvmlt function (and , if are the same size as The vecsmltf ) uses SIMD by default. Refer to Implications of Using vecsmlt doubles floats SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-233 Documented Library Functions vecssub vector - scalar subtraction Synopsis #include float *vecssubf (const float dm a[], float scalar, float dm output[], int samples); double *vecssub (const double dm a[], double scalar, double dm output[], int samples); long double *vecssubd (const long double dm a[], long double scalar, long double dm output[], int samples); Description The vecssub functions compute the difference of each element of the vector a[], minus the scalar. Both the input and output vectors are samples in size. The functions return a pointer to the output vector. Error Conditions None. 2-234 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define N 100 double input[N], result[N]; double x; vecssub (input, x, result, N); See Also cvecssub, vecsadd, vecsmlt, vecvsub function (and , if are the same size as The vecssubf ) uses SIMD by default. Refer to Implications of Using vecssub doubles floats SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-235 Documented Library Functions vecvadd Vector + vector addition Synopsis #include float *vecvaddf (const float dm a[], const float dm b[], float dm output[], int samples); double *vecvadd (const double dm a[], const double dm b[], double dm output[], int samples); long double *vecvaddd (const long double dm a[], const long double dm b[], long double dm output[], int samples); Description The vecvadd functions compute the sum of each of the elements of the vectors a[] and b[], and store the result in the output vector. All three vectors are samples in size. The functions return a pointer to the output vector. Error Conditions None. 2-236 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define N 100 double input_1[N]; double input_2[N], result[N]; vecvadd (input_1, input_2, result, N); See Also cvecvadd, vecsadd, vecvmlt, vecvsub function (and , if are the same size as The vecvaddf ) uses SIMD by default. Refer to Implications of Using vecvadd doubles floats SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-237 Documented Library Functions vecvmlt Vector * vector multiplication Synopsis #include float *vecvmltf (const float dm a[], const float dm b[], float dm output[], int samples); double *vecvmlt (const double dm a[], const double dm b[], double dm output[], int samples); long double *vecvmltd (const long double dm a[], const long double dm b[], long double dm output[], int samples); Description The vecvmlt functions compute the product of each of the elements of the vectors a[] and b[], and store the result in the output vector. All three vectors are samples in size. The functions return a pointer to the output vector. Error Conditions None. 2-238 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define N 100 double input_1[N]; double input_2[N], result[N]; vecvmlt (input_1, input_2, result, N); See Also cvecvmlt, vecsmlt, vecvadd, vecvsub function (and , if are the same size as The vecvmltf ) uses SIMD by default. Refer to Implications of Using vecvmlt doubles floats SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-239 Documented Library Functions vecvsub Vector - vector subtraction Synopsis #include float *vecvsubf (const float dm a[], const float dm b[], float dm output[], int samples); double *vecvsub (const double dm a[], const double dm b[], double dm output[], int samples); long double *vecvsubd (const long double dm a[], const long double dm b[], long double dm output[], int samples); Description The vecvsub functions compute the difference of each of the elements of the vectors a[] and b[], and store the result in the output vector. All three vectors are samples in size. The functions return a pointer to the output vector. Error Conditions None. 2-240 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors DSP Run-Time Library Example #include #define N 100 double input_1[N]; double input_2[N], result[N]; vecvsub (input_1, input_2, result, N); See Also cvecvsub, vecssub, vecvadd, vecvmlt function (and , if are the same size as The vecvsubf ) uses SIMD by default. Refer to Implications of Using vecvsub doubles floats SIMD Mode for more information. CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors 2-241 Documented Library Functions zero_cross Count zero crossings Synopsis #include int zero_crossf (const float in[], int length); int zero_cross (const double in[], int length); int zero_crossd (const long double in[], int length); Description The zero_cross functions return the number of times that a signal represented in the input array in[] crosses over the zero line. If all the input values are either positive or zero, or they are all either negative or zero, then the functions return a zero. Error Conditions None. Example #include #define SIZE 256 double input[SIZE]; int result; result = zero_cross (input, SIZE); See Also No related functions. 2-242 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors I INDEX A abend, see abort function abort (abnormal program end) function, 1-66 Abridged C++ library, 1-36 abs (absolute value, int) function, 1-67 absfx (absolute value) function, 1-68 absolute value, see abs, fabs, labs functions a_compress function, 2-25 a_compress_vec (A-law compression) function, 2-25 acos (arc cosine) functions, 1-69 adi_dump_all_heaps (dump current state of all heap to file) function, 1-70 adi_dump_heap (dump current state of heap to file) function, 1-72 adi_fatal_error (handle non-recoverable error) function, 1-74 adi_fatal_exception (handle non-recoverable exception) function, 1-76 adi_heap_debug_disable (disable features of heap debugging) function, 1-78 adi_heap_debug_end (finish heap debugging) function, 1-82 adi_heap_debug_flush (flush heap debugging output buffer) function, 1-84 adi_heap_debug_pause (temporarily disable heap debugging) function, 1-86 adi_heap_debug_reset_guard_region (reset bit patterns) function, 1-88 adi_heap_debug_resume (re-enable heap debugging) function, 1-90 adi_heap_debug_set_buffer (configure buffer for heap debugging) function, 1-92 adi_heap_debug_set_call_stack_depth (change depth of call stack recorded by heap debugging library) function, 1-94 adi_heap_debug_set_error (change error types to be regarded as terminating errors) function, 1-96 adi_heap_debug_set_guard_region (change the bit patterns written to guard regions around memory blocks) function, 1-98 adi_heap_debug_set_ignore (change error types to be ignored) function, 1-101 adi_heap_debug_set_warning (change error types to be regarded as run-time warning) function, 1-103 adi_types.h header file, 1-15 adi_verify_all_heaps (verify that no heaps contain corrupt blocks) function, 1-105 adi_verify_heap (verify heap contains no corrupt blocks) function, 1-107 ADSP-2106x functions cartesian, 2-45 cfftN, 2-56 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors I-1 Index ADSP-2106x functions (continued) fminf, 2-133 ifftN, 2-161, 2-165 polar, 2-197 ADSP-2106x processors built-in DSP functions, 2-16 ADSP-2116x/2126x/2136x functions a_compress, 2-25 a_compress_vec, 2-25 a_expand, 2-27 a_expand_vec, 2-27 alog, 2-29 alog10, 2-30 arg, 2-31 autocoh, 2-33 autocorr, 2-35 biquad, 2-37 cabs, 2-42 cadd, 2-44 cexp, 2-49 cfft, 2-51 cfftf, 2-63 cfft_mag, 2-54 cfftN, 2-60 cmatmadd, 2-66 cmatmmlt, 2-68 cmatmsub, 2-71 cmatsadd, 2-73 cmatsmlt, 2-75 cmatssub, 2-77 cmlt, 2-79 copysign, 2-83 cot, 2-84 crosscoh, 2-86 crosscorr, 2-89 csub (complex subtraction), 2-92 cvecdot, 2-93 cvecsadd, 2-95 cvecsmlt, 2-97 cvecssub, 2-99 I-2 functions (continued) cvecvadd, 2-101 cvecvmlt, 2-103 cvecvsub, 2-105 favg, 2-107 fclip, 2-108 fftf_magnitude, 2-113 fft_magnitude, 2-109 fir, 2-116 fir_decima, 2-120 fir_interp, 2-123 fmax, 2-132 fmin, 2-133 histogram, 2-153 ifft, 2-155 iir, 2-168 matinv, 2-176 matmadd, 2-178 matmmlt, 2-180 matsadd, 2-184 matsmlt, 2-186 matssub, 2-188 matsub, 2-182 mean, 2-190 mu_compress, 2-191 mu_expand, 2-193 norm, 2-195 polar, 2-197 rfft, 2-199 rfftf_2, 2-205 rfft_mag, 2-203 rfftN, 2-208, 2-211 rms, 2-215 rsqrt, 2-217 SIMD execution model, 2-61, 2-166, 2-212 transpm, 2-218 twidfftf, 2-220, 2-223 var, 2-226 vecdot, 2-228 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Index functions (continued) vecsadd, 2-230 vecsmlt, 2-232 vecssub, 2-234 vecvadd, 2-236 vecvmlt, 2-238 vecvsub, 2-240 zero_cross, 2-242 ADSP-2116x/2126x/2136x processors DSP run-time library reference, 2-24 a_expand (A-law expansion) function, 2-27 A-law compression function, ADSP-2106x DSPs, 2-25 compression function, ADSP-21160 DSP, 2-25 expansion function, ADSP-21160 DSP, 2-27 A-law (companders), ADSP-2106x, 2-5 algebraic functions, see math functions algorithm header file, 1-41 allocate memory, see calloc, free, malloc, realloc functions alog10 functions, 2-30 alog functions, 2-29 alphabetic character test, see isalpha function alphanumeric character test, see isalnum function anti-log base 10 functions, 2-30 functions, 2-29 arg (get phase of a complex number) functions, 2-31 argument list formatting into a character array, 1-439 formatting into n-character array, 1-437 array search, binary, see bsearch function ASCII string, see atof, atoi, atol, atold functions asctime (convert broken-down time into string) function, 1-109, 1-142 asctime function, 1-33 asin (arc sine) functions, 1-111 asm_sprt.h header file, 2-5 assert.h header file, 1-15 assert macro, 1-15 atan2 (arc tangent division) functions, 1-113 atan (arc tangent) functions, 1-112 atexit (select exit) function, 1-114 atof (convert string to double) function, 1-115 atoi (string to integer) function, 1-118 atold (convert string to long double) function, 1-120 atoll (convert string to long long integer) function, 1-123 atol (string to long integer) function, 1-119 autocorr (autocorrelation of a signal) functions, 2-35 average (mean of 2 int) function, 1-124 B base 10, anti-log functions, 2-30 basic cycle counting, 1-44 benchmarking C-compiled code, 1-51 binary array search, see bsearch function binary stream, 1-225 bin_size parameter, 2-153 biquad function, 2-37 bit definitions, processor-specific, 2-12 bitsfx (bitwise fixed-point to integer conversion) function, 1-125 broken-down time gmtime, 1-253 localtime, 1-314 mktime, 1-328 strftime, 1-387 time.h header file, 1-31 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors I-3 Index bsearch (array search, binary) function, 1-126 buffering, for a file or stream, 1-365 BUFSIZ macro, 1-225 built-in functions ADSP-2106x processors, 2-16 C compiler, 1-35 C C++ Abridged Library, 1-36 cabs (complex absolute value) functions, 2-42 cadd (complex addition) functions, 2-44 calendar time, 1-31, 1-423 calling C/C++ run-time library functions, 1-3 calloc (allocate initialized memory) function, 1-129 cartesian (cartesian to polar) functions, 2-45 cartesian number phase, 2-31 C-compiled code, benchmarking, 1-51 C/C++ run-time library functions, calling, 1-3 C/C++ run-time library guide, 1-2 to 1-43 Cdef*.h header files, 2-13 cdiv (complex division) functions, 2-47 ceil (ceiling) functions, 1-131 cexp (complex exponential) functions, 2-49 cfft (complex radix-2 FFT) function, 2-51 cfftf (fast N point complex input FFT) function, 2-63 cfft_mag (cfft magnitude) function, 2-54 cfftN (N-point complex input FFT) functions, 2-56, 2-60 character string search, recursive, see strrchr function character string search, see strchr function I-4 clearerr (clear error indicator) function, 1-132 clip (x by y, int) function, 1-134 clock (processor time) function, 1-49, 1-52, 1-135 CLOCKS_PER_SEC macro, 1-31, 1-49, 1-51 clock_t data type, 1-31, 1-49, 1-135 cmatmadd (complex matrix + matrix addition) functions, 2-66 cmatmmlt (complex matrix matrix multiplication) functions, 2-68 cmatmsub (complex matrix - matrix subtraction) functions, 2-71 cmatrix.h header file, 2-5 cmatsadd (complex matrix scalar addition) functions, 2-73 cmatsmlt (complex matrix scalar multiplication) function, 2-75 cmatssub (complex matrix scalar subtraction) functions, 2-77 cmlt (complex multiplication) functions, 2-79 compare memory range, see memcmp function compare strings, see strcmp, strcoll, strcspn, strpbrk, strncmp, strstr functions complex addition functions, 2-44 conjugate function, 2-80 division functions, 2-47 exponential function, 2-49 matrix functions, 2-5 matrix matrix addition functions, 2-66 matrix matrix multiplication functions, 2-68 matrix matrix subtraction function, 2-71 matrix scalar addition function, 2-73 matrix scalar multiplication function, 2-75 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Index complex (continued) multiplication functions, 2-79 number (phase of), 2-31 radix-2 Fast Fourier transform, 2-51 subtraction functions, 2-92 vector dot product function, 2-93 vector functions, 2-7 complex_float operator, 1-37 complex.h header file ADSP-2106x DSPs, 2-6 embedded C++ header fle, 1-37 complex_long_double operator, 1-37 concatenate, string, see strcat, strncat function conj (complex conjugate) functions, 2-80 constructs, from polar coordinates (polar function), 2-197 control character test, see iscntrl function conversion specifiers, 1-220, 1-387 convert, characters, see tolower, toupper functions convert, strings to long integer, see atof, atoi, atol, strtok, strtol, strtoul, functions convolution, of input vectors, 2-81 convolve (convolution) function, 2-81 copy, string, see strcpy, strncpy function copy memory range, see memcpy function copysign functions, 2-83 cos (cosine) functions, 1-137 cosh (hyperbolic cosine) functions, 1-138 cot (cotangent) functions, 2-84 countlsfx (count leading sign or zero bits) function, 1-140 count_ones (count one bits in word) function, 1-139 CrossCore Embedded Studio simulator, 1-28 crosscorr (cross-correlation) functions, 2-89 C run-time library functions interrupt-safe versions, 1-34 C run-time library reference, 1-65 to 1-432 csub (complex subtraction) functions, 2-92 ctime (convert calendar time into string) function, 1-109, 1-142 C-type functions isalnum, 1-278 isalpha, 1-279 iscntrl, 1-280 isdigit, 1-281 isgraph, 1-282 islower, 1-283, 1-285 isprint, 1-288 ispunct, 1-289 isspace, 1-290 isupper, 1-292 isxdigit, 1-293 tolower, 1-424 toupper, 1-425 ctype.h header file, 1-16, 1-58, 1-60, 2-20 cvecdot (complex vector dot product) functions, 2-93 cvecsadd (complex vector scalar addition) functions, 2-95 cvecsmlt (complex vector scalar multiplication) functions, 2-97 cvecssub (complex vector scalar subtraction) functions, 2-99 cvector.h header file, 2-7 cvecvadd (complex vector addition) functions, 2-101 cvecvmlt (complex vector multiplication) functions, 2-103 cvecvsub (complex vector subtraction) functions, 2-105 cycle count cycle_count.h header file, 1-16 register, 1-44, 1-52 with statistics, 1-46 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors I-5 Index cycle_count.h header file, 1-16, 1-44 cycle count register, 1-46 cycle counts, 1-49 cycles.h header file, 1-17, 1-33, 1-46 CYCLES_INIT(S) macro, 1-46 CYCLES_PRINT(S) macro, 1-46 CYCLES_RESET(S) macro, 1-46 CYCLES_START(S) macro, 1-46 CYCLES_STOP(S) macro, 1-46 cycle_t data type, 1-44 D data_imag array, 2-63, 2-158 data_real array, 2-63, 2-158 daylight saving flag, 1-31 -DCLOCKS_PER_SEC= compile-time switch, 1-51 -DDO_CYCLE_COUNTS compile-time switch, 1-46, 1-52 -DDO_CYCLE_COUNTS switch, 1-45 deallocate memory, see free function decimation index, 2-120 def21160.h header file, 2-12 def21161.h header file, 2-12 def21261.h header file, 2-12 def21262.h header file, 2-12 def21266.h header file, 2-12 def21363.h header file, 2-12 def21364.h header file, 2-12 def21365.h header file, 2-12 def21366.h header file, 2-12 def21367.h header file, 2-12 def21368.h header file, 2-12 def21369.h header file, 2-12 def21371.h header file, 2-12 def21375.h header file, 2-12 def21467.h header file, 2-12 def21469.h header file, 2-12 I-6 def21479.h header file, 2-12 def21489.h header file, 2-12, 2-13 default memory placement, 1-13 deque header file, 1-41 difftime (difference between two calendar times) function, 1-144 digit character test, see isdigit function div (division, int) function, 1-146 divifx (division of integer by fixed-point) function, 1-148 division, complex, 2-47 division, see div, ldiv functions double representation, 1-399 DSP library functions, 2-2 calling, 2-2 DSP run-time library calls, 2-2 dyn_AddHeap function, 1-149 dyn_alloc function, 1-151 dyn_AllocSectionMem function, 1-153 dyn_AllocSectionMemHeap function, 1-156 Dynamically-loadable mdoules dyn_FreeEntryPointArray function, 1-161 dyn_GetEntryPointArray function, 1-164 Dynamically-loadable mdules dyn_alloc function, 1-151 dyn_heap_init function, 1-179 Dynamically-loadable modules dyn_GetHeapForWidth function, 1-169 dyn_RewriteImageToFile function, 1-190 dyn_SetSectionMem function, 1-194 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Index dynamically-loadable modules allocate section memory, 1-153 allocate section memory from heap, 1-156 copy section contents, 1-159 dyn_RecordRelocOutOfRange function, 1-184 dyn_RetrieveRelocOutOfRange function, 1-188 free section memory, 1-162 get exported symbol table, 1-167 get number of sections, 1-171 get sections, 1-173 get string table, 1-175 get string table size, 1-177 look up symbol by name, 1-181 relocate image, 1-186 set section address, 1-192 validate image, 1-196 dyn_CopySectionContents function, 1-159 dyn_FreeEntryPointArray function, 1-161 dyn_FreeSectionMem function, 1-162 dyn_GetEntryPointArray function, 1-164 dyn_GetExpSymTab function, 1-167 dyn_GetHeapForWidth function, 1-169 dyn_GetNumSections function, 1-171 dyn_GetSections function, 1-173 dyn_GetStringTable function, 1-175 dyn_GetStringTableSize function, 1-177 dyn_heap_init function, 1-179 dyn_LookupByName function, 1-181 dyn_RecordRelocOutOfRange function, 1-184 dyn_Relocate function, 1-186 dyn_RetrieveRelocOutOfRange function, 1-188 dyn_RewriteImageToFile function, 1-190 dyn_SetSectionAddr function, 1-192 dyn_SetSectionMem function, 1-194 dyn_ValidateImage function, 1-196 E EDOM macro, 1-23 Embedded C++ library header files complex, 1-37 exception, 1-37 fstream, 1-38 fstreams.h, 1-43 iomanip, 1-38 ios, 1-38 iosfwd, 1-38 iostream, 1-38 iostream.h, 1-43 istream, 1-38 new, 1-38 new.h, 1-43 ostream, 1-38 sstream, 1-39 stdexcept, 1-39 streambuf, 1-39 string, 1-39 strstream, 1-39 embedded standard template library, 1-41 EMUCLK register, 1-46, 1-53 end, see atexit, exit functions ERANGE macro, 1-23 errno global variable, 1-33, 1-35 errno.h header file, 1-17 errrno global variable, 1-386 exception header file, 1-37 exit (program termination) function, 1-198 exp (exponential) functions, 1-199 exponential, see exp, ldexp functions exponentiation, 2-29, 2-30 external memory long word access, 2-19 reading from, 1-347 restrictions, 2-19 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors I-7 Index external memory (continued) SIMD access, 2-19 writing to, 1-441 EZ-KIT Lite system supporting primitives for open, close, read, write, and seek operations, 1-28 F fabs (absolute value) functions, 1-200 far jump return, see longjmp, setjmp functions Fast FIR function, 2-128 fast N-point complex input FFT (cfftf) function, 2-158 fast N-point complex radix-2 Fast Fourier transform, 2-63 fast parallel real radix-2 Fast Fourier Transform, 2-205 fatal error handling, 1-54 FatalError.xml, 1-55 global variables used, 1-54 library error specific codes, 1-56 favg (mean of two values) functions, 2-107 fclip (clip) function, 2-108 fclose (close stream) function, 1-201 feof (test for end of file) function, 1-203, 1-204 fflush (flush a stream) function, 1-205 FFT, see Fast Fourier Transform functions fftf_magnitude (FFTF magnitude) function, 2-113 fft_magnitude (FFT magnitude) function, 2-109 FFT twiddle factors for fast FFT, 2-223 fgetc (get character from stream) function, 1-206 fgetpos (record current position in stream) function, 1-208 fgets (get string from stream) function, 1-210 I-8 file descriptor, 1-212, 1-277 file I/O support, 1-53 fileno function, 1-212 file opening, 1-215 FILE pointer, 1-35 fill memory range, see memset function filter.h header file, 2-7 filters.h header file, 2-9 finish processing argument list, see va_end function finite impulse response (FIR) filter, 2-116 FIR-based decimation filter, 2-120 FIR-based interpolation filter, 2-123 fir_decima (FIR-based decimation filter) function, 2-120 firf function, 2-128 FIR filter, 2-116 fir (finite impulse response) function, 2-116, 2-168 fir_interp (FIR interpolation filter) function, 2-123 flash memory, mapping objects using attributes, 1-13 float.h header file, 1-17, 1-18 floor (integral value) functions, 1-213 FLT_MAX macro, 1-17 FLT_MIN macro, 1-17 fmax (maximum) functions, 2-132 fmin (float minimum) functions, 2-133 fmod (floating-point modulus) functions, 1-214 fopen (open file) function, 1-215 formatted input, reading, 1-232 formatted output printing, 1-217 printing variable argument list in, 1-433 fprintf (print formatted output) function, 1-217 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Index fputc (put character on stream) function, 1-223 fputs (put string on stream) function, 1-224 fread (buffered input) function, 1-225 free (deallocate memory) functions, 1-227 freopen (open existing file) function, 1-228 frexp (fraction/exponent) functions, 1-230 fscanf (read formatted input) function, 1-232 fseek (sets the file position) function, 1-237 fsetpos (reposition file pointer) function, 1-239 fstream header file, 1-38 fstream.h header file, 1-43 ftell (obtain current file position) function, 1-240 FuncName attribute, 1-9 functional header file, 1-41 function primitive I/O, 1-27 fwrite (buffered output) function, 1-242 fxbits (bitwise integer to fixed-point conversion) function, 1-244 fxdivi (division of integer by integer) function, 1-245 gen_rectangular (generate rectangular window) function, 2-148 gen_triangle (generate triangle window) function, 2-150 gen_vohann (generate von hann window) function, 2-152 getc (get character from stream) function, 1-246 getchar (get character from stdin) function, 1-248 getenv (get string definition from operating system) function, 1-250 get locale pointer, see localeconv function get next argument in list, see va_arg function gets (get string from stream) function, 1-251 gmtime (convert calendar time into broken-down time as UTC) function, 1-314 gmtime (convert calendar time to broken-down time) function, 1-253 gmtime function, 1-33, 1-109 graphical character test, see isgraph function G H gen_bartlett (generate bartlett window) function, 2-134 gen_blackman (generate blackman window) function, 2-136 gen_gaussian (generate gaussian window) function, 2-138 gen_hamming (generate hamming window) function, 2-140 gen_hanning (generate hanning window) function, 2-142 gen_harris (generate harris window) function, 2-144 gen_kaiser (generate kaiser window) function, 2-146 hash_map header file, 1-41 hash_set header file, 1-41 header files , 1-24 adi_types.h, 1-15 cvector.h, 2-7 def21160.h, 2-12 def21161.h, 2-12 def21261.h, 2-12 def21262.h, 2-12 def21266.h, 2-12 def21267.h, 2-5 def21363.h, 2-12 def21364.h, 2-12 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors I-9 Index header files (continued) def21365.h, 2-12 def21366.h, 2-12 def21367.h, 2-12 def21368.h, 2-12 def21369.h, 2-12 def21467.h, 2-12 def21469.h, 2-12 def21479.h, 2-12 def21489.h, 2-12, 2-13 defining processor-specific symbolic names, 2-12 DSP, list of, 2-5 embedded standard template library, 1-43 heap_debug.h, 1-18 instrprof.h, 1-21 working with, 1-13 header files (ADSP-2106x) asm_sprt.h, 2-5 Cdef*.h, 2-13 cmatrix.h, 2-5 comm.h, 2-5 complex.h, 2-6 filters.h, 2-7, 2-9 list of, 2-4 macros.h, 2-9 math.h, 2-9 matrix.h, 2-11 platform_include.h, 2-11 stats.h, 2-14 sysreg.h, 2-14 trans.h, 2-14 vector.h, 2-15 window.h, 2-15 header files (C++ for C facilities) cassert, 1-40 cctype, 1-40 cerrno, 1-40 cfloat, 1-40 I-10 header files (C++ for C facilities)(continued) climits, 1-40 clocale, 1-40 cmath, 1-40 csetjmp, 1-40 csignal, 1-40 cstdarg, 1-40 cstddef, 1-40 cstdio, 1-40 cstdlib, 1-40 cstring, 1-40 header files (standard) misra_types.h, 1-24 stdfix.h, 1-25 stdint.h, 1-25 heap allocating and initializing memory, 1-255, 1-259, 1-263, 1-270 allocating memory from, 1-265 allocating uninitialized memory, 1-320 changing memory allocation from, 1-267 heap_calloc function, 1-255 index, 1-263 re-initializing, 1-259 return memory to, 1-257 space unused in, 1-373 heap_calloc function, 1-255 heap debugging configuration macros, 1-18 error type macros, 1-20 heap_debug.h header file defined, 1-18 library functions, 1-59 heap_free function, 1-257 heap index, 1-263 heap_init function, 1-259 heap_install function, 1-261 heap_lookup function, 1-263 heap_malloc function, 1-265, 1-272 heap_realloc function, 1-267 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Index heap_space_unused function, 1-270 hexadecimal digit test, see isxdigit function histogram function, 2-153 HUGE_VAL macro, 1-23 hyperbolic, see cosh, sinh, tanh functions I idivfx (division of fixed-point by fixed-point) function, 1-274 idivfx functions, 1-274 ifftf (inverse complex radix-2 Fast Fourier Transform) function, 2-158 ifft (inverse complex radix-2 Fast Fourier Transform) function, 2-155 ifftN (N-point radix-2 inverse Fast Fourier transform) functions, 2-161, 2-165 iir (infinite impulse response) function, 2-171 initialize argument list, see va_start function input, formatted, 1-232 instrprof.h header file, 1-21 instrprof_request_flush (flush instrumented profiling data to host) function, 1-275 Interrupts, 2-3 interrupt-safe functions, 1-33 inverse, see acos, asin, atan, atan2 functions inverse complex radix2 Fast Fourier transform, 2-155 I/O buffer, 1-366 functions, 1-27 ioctl function, 1-277 iomanip.h header file, 1-38, 1-43 iosfwd header file, 1-38 ios header file, 1-38 iostream.h header file, 1-38, 1-43 isalnum (alphanumeric character test) function, 1-278 isalpha (alphabetic character test) function, 1-279 iscntrl (control character test) function, 1-280 isdigit (digit character test) function, 1-281 isgraph (graphical character test) function, 1-282 isinf (test for infinity) function, 1-283 islower (lower case character test) function, 1-285 isnan (test for NAN) function, 1-286 iso646.h (Boolean operator) header file, 1-21 isprint (printable character test) function, 1-288 ispunct (punctuation character test) function, 1-289 isspace (white space character test) function, 1-290 istream header file, 1-38 isupper (uppercase character test) function, 1-292 isxdigit (hexadecimal digit test) function, 1-293 iterator header file, 1-41 L labs (absolute value, long) function, 1-294 lavg (mean of two values) function, 1-295, 1-302 LC_COLLATE macro, 1-383 lclip (clip) function, 1-296 lconv struct members, 1-311 lcount_ones (count one bits in word) function, 1-297 ldexp (exponential, multiply) functions, 1-298 ldiv (division, long) function, 1-299 length modifier, 1-219 libFunc attribute, 1-9 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors I-11 Index libfunc.dlb library, object attributes, 1-10 libGroup attribute, 1-9 values, 1-12 libio.dlb library, linking with, 1-27 libio*_lite.dlb libraries selecting with -flags-link -MD__LIBIO_LITE switch, 1-5 libName attribute, 1-9 ___lib_prog_term label, 1-198 libraries functions, documented, 1-58, 2-20 libraries, in multi-threaded environment, 1-34 library attribute convention exceptions, 1-12 source code, working with, 2-3 library functions called from ISR, 1-33 limits.h header file, 1-22 list header file, 1-42 llabs (absolute value) function, 1-301 llavg (mean of two values) function, 1-302 llclip (clip) function, 1-303 llcount_ones (count one bits in long long) function, 1-304 lldiv (long long divison) function, 1-305 llmax (long long maximum) function, 1-307 llmin (long long minimum) function, 1-308 lmax (long maximum) function, 1-307, 1-309 lmin (long minimum) function, 1-308, 1-310 localeconv (localization pointer) function, 1-311 locale.h header file, 1-22 localization, see localeconv, setlocale, strxfrm functions I-12 localtime (convert calendar time into broken-down time) function, 1-314 localtime (convert calendar time to broken-down time) function, 1-253 localtime function, 1-33, 1-109 log10 (log base 10) functions, 1-317 log (log base e) functions, 1-316 long double, representation, 1-409 longjmp (far jump return) function, 1-318 long jump, see longjmp, setjmp functions lowercase, see islower, tolower functions M macro.h header file, 2-9 macros EDOM, 1-23 ERANGE, 1-23 for measuring the performance of compiled C source, 1-46 HUGE_VAL, 1-23 LC_COLLATE, 1-383 malloc (allocate uninitialized memory) function, 1-320 map header file, 1-42 math functions acos, 1-69 additional, 2-9 asin, 1-111 atan, 1-112 atan2, 1-113 average, 1-30 ceil, 1-131, 1-132 clip, 1-30 cos, 1-137 cosh, 1-138 count bits set, 1-30 exp, 1-199 fabs, 1-200 floor, 1-213 fmod, 1-214 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Index math functions (continued) frexp, 1-230 ldexp, 1-298 log, 1-316 log10, 1-317 maximum, 1-30 minimum, 1-30 modf, 1-331 multiple heaps, 1-30 pow, 1-337 rsqrt, 2-217 sin, sinf, 1-369 sinh, 1-370 sin (sine), 1-369 sqrt, 1-376 standard, 2-9 tan, 1-421 tanh, 1-422 math.h header file, 1-22, 1-58, 2-9, 2-20 matinv (real matrix inversion) functions, 2-176 matmadd (matrix addition) functions, 2-178 matmmlt (matrix multiplication) functions, 2-180 matmsub (matrix subtraction) functions, 2-182 matrix addition functions, 2-178 matrix.h header file, 2-11 matrix scalar addition functions, 2-184 matrix transpose (transpm) function, 2-218 matsmlt (real matrix scalar multiplication) functions, 2-186 matssub (real matrix scalar subtraction) function, 2-188 matsub (matrix subtraction) function, 2-182 max (maximum) function, 1-321 mean functions, 2-190 memchr (find character) function, 1-322 memcmp (compare memory range) function, 1-323 memcpy (copy memory range) function, 1-324 memmove (move memory range) function, 1-325 memory default placement, 1-13 header file, 1-42 initializer support files, 1-9 memory functions, see calloc, free, malloc, memcmp, memcpy, memset, memmove, memchar, realloc functions memory initializer initializing code/data from flash memory, 1-13 memory-mapped registers (MMR), accessing from C/C++ code, 2-13 memset (fill memory range) function, 1-326 min (minimum) function, 1-327 misra_types.h header file, 1-24 mixed C/assembly support, 2-5 mktime (convert broken-down time into a calendar) function, 1-328 modf (modulus, float) functions, 1-331 move memory range, see memmove function mu_compress (-law compression) function, 2-191 mu_expand (-law expansion) function, 2-193 mulifx functions, 1-332 mulifx (multiplication of integer by fixed-point) function, 1-332 multiple heaps, 1-261 multi-threaded environment, 1-34 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors I-13 Index N natural logarithm, see log functions NDEBUG macro, 1-16 new header file, 1-38 new.h header file, 1-43 normalized fraction, see frexp functions norm (normalization) functions, 2-195 Not a Number (NaN) test, 1-286 N-point complex input FFT functions, 2-56, 2-60 N-point inverse FFT functions, 2-161, 2-165 N-point real input FFT functions, 2-208, 2-211 numeric header file, 1-42 O objects, copy characters between overlapping, 1-325 ostream header file, 1-38 PRINT_CYCLES(STRING,T) macro, 1-44 printf (print formatted output) function described, 1-338 processor clock rate, 1-50 time, 1-135 processor counts, measuring, 1-43 processor cycles, counting, 1-49 program control functions calloc, 1-129 free, 1-227 malloc, 1-320 realloc, 1-349 program termination, 1-28 punctuation character test (ispunct) function, 1-289 putchar (write character to stdout) function, 1-341 putc (put character on stream) function, 1-340 puts (put string on stream) function, 1-342 P perror (print error message) function, 1-333 pgo_hw.h header file, 1-24 pgo_hw_request_flush (request a flush) function, 1-335 platform_include.h header file, 2-11 polar (construct from polar coordinates) functions, 2-197 polar coordinate conversion, 2-197 power, see exp, pow, functions pow (power, x^y) functions, 1-337 precision value, 1-219 prefersMem attribute, 1-9 default memory placement using, 1-13 prefersMemNum attribute, 1-9 printable character test, see isprint function I-14 Q qsort (quicksort) function, 1-343 queue header file, 1-42 R raise (force a signal) function, 1-345 rand function, 1-33 random number, see rand, srand functions, 1-346 rand (random number generator) function, 1-346 read_extmem (read external memory) function, 1-347 realloc (allocate used memory) function, 1-349 real matrix inversion, 2-176 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Index real radix-2 Fast Fourier Transform function, 2-199 reciprocal square root function, see rsqrt functions Reentrancy, 2-3 remove (remove file) function, 1-351 rename (rename file) function, 1-352 requiredForROMBoot attribute, 1-13 rewind (reset file position indicator in stream) function, 1-354 rfftf_2 (fast parallel rfft) function, 2-205 rfft_mag (rfft magnitude) function, 2-203 rfftN (N-point rfft) functions, 2-208, 2-211 rfft (real radix-2 Fast Fourier Transform) function, 2-199 roundfx (round fixed-point value) function, 1-356 rsqrt (reciprocal square root) math functions, 2-217 run-time label, 1-362 library attributes, listed, 1-8 S scanf (convert formatted input) function, 1-358 search character string, see strchr, strrchr functions search memory, character, see memchar function send string to operating system, see system function setbuf (specify full buffering) function, 1-360 set header file, 1-42 setjmp (define runtime label) function, 1-362 setjmp.h header file, 1-24, 1-58, 2-20 set jump, see longjmp, setjmp functions setlocale (set localization) function, 1-364 setvbuf (allocate buffer from alternative memory) function, 1-29, 1-365 SIGABRT handler, 1-66 signal autocorrelation, 2-35 signal (define signal handling) function, 1-367 signal functions raise, 1-345 signal, 1-367 signal.h header file, 1-24, 1-58, 2-20 SIMD mode, with ADSP-2116x/2126x/2136x processors, 2-17 sine, see sin, sinh functions sinh (sine hyperbolic) functions, 1-370 sin (sine) functions, 1-369 snprintf (format into n-character array) function, 1-371 space_unused function, 1-373 sprintf (format into character array) function, 1-374 sqrt (square root) functions, 1-376 srand (random number seed) function, 1-33, 1-377 sscanf (convert formatted input) function, 1-378 sstream header file, 1-39 stack header file, 1-42 standard argument functions va_arg, 1-428 va_end, 1-431 va_start, 1-432 standard C library, header files, 1-14 to 1-31 standard error stream, 1-333 standard header files assert.h, 1-15 ctype.h, 1-16 cycle_count.h, 1-16 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors I-15 Index standard header files cycles.h, 1-17 errno.h, 1-17 float.h, 1-17 heap_debug.h, 1-18 iso646.h, 1-21 limits.h, 1-22 locale.h, 1-22 math.h, 1-22 setjmp.h, 1-24 signal.h, 1-24 stdarg.h, 1-24 stdbool.h, 1-25 stddef.h, 1-25 stdio.h, 1-27 stdlib.h, 1-29 string.h, 1-31 time.h, 1-31 standard library functions abort, 1-66 abs, 1-67, 1-140 absfx, 1-68 acos, 1-69 atexit, 1-114 atoi, 1-118 atol, 1-119 avg, 1-124 bitsfx, 1-125 bsearch, 1-126 calloc, 1-129 clip, 1-134 countlsfx, 1-140 count_ones, 1-139 div, 1-146 divifx, 1-148 exit, 1-198 free, 1-227 fxbits, 1-244 fxdivi, 1-245 getenv, 1-250 I-16 (continued) standard library functions (continued) heap_calloc, 1-255 heap_free, 1-257, 1-259 heap_install, 1-261 heap_lookup, 1-263 heap_malloc, 1-265 heap_realloc, 1-267 heap_space_unused, 1-270 heap_switch, 1-272 idivfx, 1-274 labs, 1-294 lavg, 1-295 lclip, 1-296 lcount_ones, 1-297, 1-304 ldiv, 1-299, 1-305 lmax, 1-309 lmin, 1-310 malloc, 1-320 max, 1-321 min, 1-327 mulifx, 1-332 qsort, 1-343 rand, 1-346 realloc, 1-349 roundfx, 1-356 space_unused, 1-373 srand, 1-377 strtol, 1-407, 1-412 strtoul, 1-414, 1-416 system, 1-420 standard math functions, 2-9 fmax, 2-132 fmin, 2-133 START_CYCLE_COUNT macro, 1-44 statistics functions, 2-14 stats.h header file, 2-14 stdarg.h header file, 1-24, 1-25, 1-58, 2-20 stddef.h header file, 1-25 stdexcept header file, 1-39 stdfix.h header file, 1-25 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Index stdint.h header file, 1-25 stdio.h header file, 1-27, 1-53, 1-58, 2-20 stdlib.h header file, 1-29, 1-30, 1-58, 2-20 library functions, 1-63 stop, see atexit, exit functions STOP_CYCLE_COUNT macro, 1-44 strcat (concatenate string) function, 1-380 strchr (search character string) function, 1-381 strcmp (compare strings) function, 1-382 strcoll (compare strings, localized) function, 1-383 strcpy (copy string) function, 1-384 strcspn (compare string span) function, 1-385 stream, closing down, 1-29 streambuf header file, 1-39 strerror (get error message string) function, 1-386 strftime (format a broken-down time) function, 1-387 string converting to fixed-point, 1-402 string compare, see strcmp, strcoll, strcspn, strncmp, strpbrk, strstr functions string concatenate, see stnrcat, strcat functions string conversion, see atof, atoi, atol, strtok, strtol, strxfrm functions string copy, see strcpy, strncpy function string functions memchar, 1-322 memcmp, 1-323 memcpy, 1-324 memmove, 1-325 memset, 1-326 strcat, 1-380 strchr, 1-381 strcmp, 1-382 strcoll, 1-383 string functions (continued) strcpy, 1-384 strcspn, 1-385 strerror, 1-386 strlen, 1-391 strncat, 1-392 strncmp, 1-393 strncpy, 1-394 strpbrk, 1-395 strrchr, 1-396 strspn, 1-397 strstr, 1-398 strtok, 1-405 strxfrm, 1-418 string.h header file, 1-31, 1-39, 1-58, 2-20 string length, see strlen function strings converting to double, 1-399 converting to long double, 1-409 strlen (string length) function, 1-391 strncat (concatenate characters from string) function, 1-392 strncmp (compare characters in strings) function, 1-393 strncpy (copy characters in string) function, 1-394 strpbrk (compare strings, pointer break) function, 1-395 strrchr (search character string, recursive) function, 1-396 strspn (string span) function, 1-397 strstr (compare string, string) function, 1-398 strstream header file, 1-39 strtod (convert string to double) function, 1-399 strtofxfx (convert string to fixed-point) function, 1-402 strtok (token to string) function, 1-33, 1-405 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors I-17 Index strtold (convert string to long double) function, 1-409 strtoll (convert string to long long integer) function, 1-412 strtol (string to long integer) function, 1-407 strtoull (convert string to unsigned long long integer) function, 1-416 strtoul (string to unsigned long tnteger) function, 1-414 struct tm, daylight savings flag, 1-31 strxfrm (localization transform) function, 1-418 symbolic names, specifying bit definitions, 2-12 sysreg.h header file, 2-14 system register bit definitions for ADSP-2116x/2126x/2136x processors, 2-12 system registers, accessing from C, 2-14 system (send string to operating system) function, 1-420 T tangent, see atan, atan2, cot, tan, tanh functions tanh (hyperbolic tangent) functions, 1-422 tan (tangent) functions, 1-421 technical support, -xxv template library header files algorithm, 1-41 deque, 1-41 functional, 1-41 hash_map, 1-41 hash_set, 1-41 iterator, 1-41 list, 1-42 map, 1-42 memory, 1-42 I-18 template library header files (continued) numeric, 1-42 queue, 1-42 set, 1-42 stack, 1-42 utility, 1-42 vector, 1-42 terminate, see atexit, exit functions Threads, 2-3 thread-safe functions, 1-33 time (calendar time) function, 1-423 time.h header file, 1-31, 1-51, 1-52 measuring cycle counts, 1-49 time_t data type, 1-31, 1-423 time zones, 1-31 tokens, string convert, see strtok function tolower (convert characters to lower case) function, 1-424 toupper (convert characters to upper case) function, 1-425 trans.h header file, 2-14 transpm (matrix transpose) functions, 2-218 trigonometric functions, see math functions twiddle coefficients, calculating, 2-220 twidfftf (generate FFT twiddle factors for fast FFT) function, 2-223 twidfft (generate FFT twiddle factors) function, 2-220 U ungetc (push character back to input) function, 1-426 uppercase, see isupper, toupper functions utility functions getenv, 1-250 system, 1-420 utility header file, 1-42 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors Index V va_arg (get next argument in list) function, 1-428 va_end (finish processing argument list) function, 1-431 variable argument list, printing formatted output, 1-433 var (variance) functions, 2-226 va_start (initialize argument list) function, 1-432 vecdot (vector dot product) functions, 2-228 vecsadd (vector scalar addition) functions, 2-230 vecsmlt (vector scalar multiplication) functions, 2-232 vecssub (vector scalar subtraction) functions, 2-234 vector functions, 2-15 vector.h header file, 1-42, 2-15 vecvadd (vector addition) functions, 2-236 vecvmlt (vector multiplication) functions, 2-238 vecvsub (vector subtraction) functions, 2-240 vfprintf (print formatted output of variable argument list) function, 1-433 volatile keyword, 1-53 vprintf (print output of variable argument list) function, 1-435 vsnprintf (format argument list into n-character array) function, 1-437 vsprintf (format argument list into character array) function, 1-439 W white space character test, see isspace function window generator functions, 2-15 window.h header file, 2-15 write_extmem (write external memory) function, 1-441 Z zero_cross (count zero crossings) functions, 2-242 zero padding, 2-163, 2-212 -law (companders) ADSP-2106x, 2-5 -law (compression function) ADSP-2116x/2126x/2136x DSPs, 2-191 -law (expansion function) ADSP-2116x/2126x/2136x DSPs, 2-193 CrossCore Embedded Studio 1.1 C/C++ Library Manual for SHARC Processors I-19 Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Analog Devices Inc.: AD-CCES-MNT-N5 AD-CCES-MNT-N1