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Diffstat (limited to 'newlib/libc/machine/i960/strncpy.S')
| -rw-r--r-- | newlib/libc/machine/i960/strncpy.S | 154 |
1 files changed, 0 insertions, 154 deletions
diff --git a/newlib/libc/machine/i960/strncpy.S b/newlib/libc/machine/i960/strncpy.S deleted file mode 100644 index 9f51b60..0000000 --- a/newlib/libc/machine/i960/strncpy.S +++ /dev/null @@ -1,154 +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 "strncpy.s" -#ifdef __PIC - .pic -#endif -#ifdef __PID - .pid -#endif -/* - * (c) copyright 1988,1993 Intel Corp., all rights reserved - */ -/* - procedure strncpy (optimized assembler version for the 80960K Series) - - dest_addr = strncpy (dest_addr, src_addr, max_bytes) - - copy the null terminated string pointed to by src_addr to the - string pointed to by dest_addr. Return the original dest_addr. - If the source string is shorter than max_bytes, then null-pad - the destination string. If it is longer than max_bytes, the - copy stops at max_bytes bytes (and no terminating null appears - in the destination string). - - This routine will fail if the source and destination string - overlap (in particular, if the end of the source is overlapped - by the beginning of the destination). The behavior is undefined. - This is acceptable according to the draft C standard. - - Undefined behavior will also 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 strncpy fetches - ahead. Disallowing the fetch ahead would impose a severe performance - penalty. - - Strategy: - - Fetch and store the strings by words and go to a character move loop - as soon as a null byte is encountered. If max_bytes is exhausted - first, then terminate after moving only max_bytes (with the last - 0, 1, 2, or 3 bytes moved as single bytes, not as a word). - Otherwise, the character move loop moves the last bytes or the - source string, and then null-pads the destination string until - max_bytes is exhausted. - - 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 and convoluted body that would be necessary to assure - alignment. - - 2) When the null byte is encountered in a source word, null out the - higher-numbered bytes in that word, store the word in the destination, - and go to the word null-padder, which may eventually go to the byte - null-padder. -*/ - - .globl _strncpy - .globl __strncpy - .leafproc _strncpy,__strncpy - .align 2 -_strncpy: -#ifndef __PIC - lda Lrett,g14 -#else - lda Lrett-(.+8)(ip),g14 -#endif -__strncpy: - mov g14, g13 - cmpibge 0,g2,Lexit # quit early if max_bytes <= 0 - ld (g1), g7 # fetch the first word of the source - mov g0, g5 - lda 0xff, g3 # byte extraction mask - addo g1, g2, g6 - addo g2, g5, g2 -Lwloop: # word copying loop - addo 4, g1, g1 # post-increment source ptr - cmpo g6, g1 # max_bytes < 4 ? - mov g7, g4 # keep a copy of source word - bl Lcloop.a # if less than four bytes to go, go to char loop - scanbyte 0, g4 # null byte found? - ld (g1), g7 # pre-fetch next word of the source - be Lcloop.c # go to char loop if null encountered - st g4, (g5) # store current word - addo 4, g5, g5 # post-increment destination ptr - b Lwloop - -Lcloop.a: # character copying loop (max_bytes < 3) - and g3, g4, g14 # extract byte -Lcloop.b: - cmpo g2, g5 # max_bytes <= 0 ? - shro 8, g4, g4 # position word to extract next byte - be Lexit # exit if max_bytes exhausted - cmpo 0, g14 # is it null? - stob g14, (g5) # store it - addo 1, g5, g5 # post-increment dest ptr - bne Lcloop.a # branch if we are NOT null padding - b Lcloop.b # branch if we are null padding - -Lexit: - mov 0, g14 - bx (g13) # g0 = dest string address; g14 = 0 -Lrett: - ret - -Lcloop.c: # character copying loop - and g3, g4, g14 # extract byte - cmpo 0, g14 # is it null? - mov g3, g7 # save mask - shlo 8, g3, g3 # shift mask to next byte position - bne Lcloop.c # loop until null found - subo 1, g7, g3 # mask to null pad after null byte - and g3, g4, g4 # null-out stuff after null byte - st g4, (g5) # store last part of src and first of null-pad - subo 8,g2,g6 # adjust max_byte counter - -Lzwloop: - cmpo g5, g6 # max_bytes < 4 ? - addo 4, g5, g5 - bg Lcloop.b # if so, goto character loop - st g14, (g5) # store four null bytes - b Lzwloop - -/* end of strncpy */ |