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Diffstat (limited to 'newlib/libc/machine/i960/strrchr.S')
| -rw-r--r-- | newlib/libc/machine/i960/strrchr.S | 137 |
1 files changed, 0 insertions, 137 deletions
diff --git a/newlib/libc/machine/i960/strrchr.S b/newlib/libc/machine/i960/strrchr.S deleted file mode 100644 index 96fe5c2..0000000 --- a/newlib/libc/machine/i960/strrchr.S +++ /dev/null @@ -1,137 +0,0 @@ -/******************************************************************************* - * - * Copyright (c) 1993 Intel Corporation - * - * Intel hereby grants you permission to copy, modify, and distribute this - * software and its documentation. Intel grants this permission provided - * that the above copyright notice appears in all copies and that both the - * copyright notice and this permission notice appear in supporting - * documentation. In addition, Intel grants this permission provided that - * you prominently mark as "not part of the original" any modifications - * made to this software or documentation, and that the name of Intel - * Corporation not be used in advertising or publicity pertaining to - * distribution of the software or the documentation without specific, - * written prior permission. - * - * Intel Corporation provides this AS IS, WITHOUT ANY WARRANTY, EXPRESS OR - * IMPLIED, INCLUDING, WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY - * OR FITNESS FOR A PARTICULAR PURPOSE. Intel makes no guarantee or - * representations regarding the use of, or the results of the use of, - * the software and documentation in terms of correctness, accuracy, - * reliability, currentness, or otherwise; and you rely on the software, - * documentation and results solely at your own risk. - * - * IN NO EVENT SHALL INTEL BE LIABLE FOR ANY LOSS OF USE, LOSS OF BUSINESS, - * LOSS OF PROFITS, INDIRECT, INCIDENTAL, SPECIAL OR CONSEQUENTIAL DAMAGES - * OF ANY KIND. IN NO EVENT SHALL INTEL'S TOTAL LIABILITY EXCEED THE SUM - * PAID TO INTEL FOR THE PRODUCT LICENSED HEREUNDER. - * - ******************************************************************************/ - - .file "strrchr.s" -#ifdef __i960_BIG_ENDIAN__ -#error "This does not work in big-endian" -#endif - -#ifdef __PIC - .pic -#endif -#ifdef __PID - .pid -#endif - -/* - * (c) copyright 1988,1993 Intel Corp., all rights reserved - */ - -/* - procedure strrchr (optimized assembler version for the 80960K series) - - src_addr = strrchr (src_addr, char) - - return a pointer to the last byte that contains the indicated - byte in the source string. Return null if the byte is not found. - - Undefined behavior will occur if the end of the source string (i.e. - the terminating null byte) is in the last two words of the program's - allocated memory space. This is so because strrchr fetches ahead. - Disallowing the fetch ahead would impose a severe performance penalty. - - Strategy: - - Fetch the source string by words and scanbyte the words for the - char until either a word with the byte is found or the null byte is - encountered. In the former case, move through the word to find the - matching byte and save its memory address, then continue the search. - In the latter case, return the saved address, or zero (null) if none - was ever found to save. - - Tactics: - - 1) Do NOT try to fetch the words in a word aligned manner because, - in my judgement, the performance degradation experienced due to - non-aligned accesses does NOT outweigh the time and complexity added - by the preamble that would be necessary to assure alignment. This - is supported by the intuition that most source arrays (even more - true of most big source arrays) will be word aligned to begin with. -*/ - - .globl _strrchr - .globl __strrchr - .leafproc _strrchr, __strrchr - .align 2 -_strrchr: -#ifdef __PIC - lda Lrett-(.+8)(ip),g14 -#else - lda Lrett,g14 -#endif -__strrchr: - - ld (g0),g4 # fetch first word - lda 0xff,g7 # byte extraction mask - and g1,g7,g1 # make char an 8-bit ordinal - shlo 8,g1,g2 # broadcast the char to four bytes - or g1,g2,g2 - shlo 16,g2,g5 - or g2,g5,g3 - mov g14,g13 # preserve return address - addo 4,g0,g2 # post-increment src pointer - mov 1,g0 # prepare to return null pointer - mov g3,g6 # prepare to return null pointer - -Lsearch_for_word_with_char_or_null: - mov g4,g5 # copy word - scanbyte 0,g5 # check for null byte - ld (g2),g4 # fetch next word of src - bo Lword_has_null # branch if null found - scanbyte g3,g5 # check for byte with char - addo 4,g2,g2 # post-increment src pointer - bno Lsearch_for_word_with_char_or_null # branch if no copy of char - mov g5,g6 # save word that has char in it (at least once) - subo 4,g2,g0 # save addr of byte after word with char - b Lsearch_for_word_with_char_or_null - -Lword_has_null: - subo 4,g2,g2 # move src pointer back to word with null -Lfind_null: - addo 1,g2,g2 # advance src pointer to byte after current - and g7,g5,g14 # extract next byte - cmpo g1,g14 # is current byte char? - shro 8,g5,g5 # position next byte for extraction - bne 1f # skip if not char sought after - mov g2,g0 # save addr of byte after char - mov g3,g6 # save word of all char to short circuit search -1: cmpobne 0,g14,Lfind_null # is current byte null? - -Lfind_last_char: - rotate 8,g6,g6 # position next highest byte - and g7,g6,g5 # extract byte - subo 1,g0,g0 # move pointer to that byte (or nullify) - cmpobne g5,g1,Lfind_last_char # branch if not at char - - bx (g13) # g0 = addr of char in src (or null); g14 = 0 -Lrett: - ret - -/* end of strrchr */ |