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Diffstat (limited to 'sysdeps/powerpc/powerpc32/strchr.S')
| -rw-r--r-- | sysdeps/powerpc/powerpc32/strchr.S | 146 |
1 files changed, 0 insertions, 146 deletions
diff --git a/sysdeps/powerpc/powerpc32/strchr.S b/sysdeps/powerpc/powerpc32/strchr.S deleted file mode 100644 index 868cbd46aa..0000000000 --- a/sysdeps/powerpc/powerpc32/strchr.S +++ /dev/null @@ -1,146 +0,0 @@ -/* Optimized strchr implementation for PowerPC. - Copyright (C) 1997-2017 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <http://www.gnu.org/licenses/>. */ - -#include <sysdep.h> - -/* See strlen.s for comments on how this works. */ - -/* char * [r3] strchr (const char *s [r3] , int c [r4] ) */ - -ENTRY (strchr) - -#define rTMP1 r0 -#define rRTN r3 /* outgoing result */ -#define rSTR r8 /* current word pointer */ -#define rCHR r4 /* byte we're looking for, spread over the whole word */ -#define rWORD r5 /* the current word */ -#define rCLZB rCHR /* leading zero byte count */ -#define rFEFE r6 /* constant 0xfefefeff (-0x01010101) */ -#define r7F7F r7 /* constant 0x7f7f7f7f */ -#define rTMP2 r9 -#define rIGN r10 /* number of bits we should ignore in the first word */ -#define rMASK r11 /* mask with the bits to ignore set to 0 */ -#define rTMP3 r12 -#define rTMP4 rIGN -#define rTMP5 rMASK - - - rlwimi rCHR, rCHR, 8, 16, 23 - li rMASK, -1 - rlwimi rCHR, rCHR, 16, 0, 15 - rlwinm rIGN, rRTN, 3, 27, 28 - lis rFEFE, -0x101 - lis r7F7F, 0x7f7f - clrrwi rSTR, rRTN, 2 - addi rFEFE, rFEFE, -0x101 - addi r7F7F, r7F7F, 0x7f7f -/* Test the first (partial?) word. */ - lwz rWORD, 0(rSTR) -#ifdef __LITTLE_ENDIAN__ - slw rMASK, rMASK, rIGN -#else - srw rMASK, rMASK, rIGN -#endif - orc rWORD, rWORD, rMASK - add rTMP1, rFEFE, rWORD - nor rTMP2, r7F7F, rWORD - and. rTMP4, rTMP1, rTMP2 - xor rTMP3, rCHR, rWORD - orc rTMP3, rTMP3, rMASK - b L(loopentry) - -/* The loop. */ - -L(loop): - lwzu rWORD, 4(rSTR) - and. rTMP5, rTMP1, rTMP2 -/* Test for 0. */ - add rTMP1, rFEFE, rWORD /* x - 0x01010101. */ - nor rTMP2, r7F7F, rWORD /* ~(x | 0x7f7f7f7f) == ~x & 0x80808080. */ - bne L(foundit) - and. rTMP4, rTMP1, rTMP2 /* (x - 0x01010101) & ~x & 0x80808080. */ -/* Start test for the bytes we're looking for. */ - xor rTMP3, rCHR, rWORD -L(loopentry): - add rTMP1, rFEFE, rTMP3 - nor rTMP2, r7F7F, rTMP3 - beq L(loop) - -/* There is a zero byte in the word, but may also be a matching byte (either - before or after the zero byte). In fact, we may be looking for a - zero byte, in which case we return a match. */ - and. rTMP5, rTMP1, rTMP2 - li rRTN, 0 - beqlr -/* At this point: - rTMP5 bytes are 0x80 for each match of c, 0 otherwise. - rTMP4 bytes are 0x80 for each match of 0, 0 otherwise. - But there may be false matches in the next most significant byte from - a true match due to carries. This means we need to recalculate the - matches using a longer method for big-endian. */ -#ifdef __LITTLE_ENDIAN__ - addi rTMP1, rTMP5, -1 - andc rTMP1, rTMP1, rTMP5 - cntlzw rCLZB, rTMP1 - addi rTMP2, rTMP4, -1 - andc rTMP2, rTMP2, rTMP4 - cmplw rTMP1, rTMP2 - bgtlr - subfic rCLZB, rCLZB, 32-7 -#else -/* I think we could reduce this by two instructions by keeping the "nor" - results from the loop for reuse here. See strlen.S tail. Similarly - one instruction could be pruned from L(foundit). */ - and rFEFE, r7F7F, rWORD - or rTMP5, r7F7F, rWORD - and rTMP1, r7F7F, rTMP3 - or rTMP4, r7F7F, rTMP3 - add rFEFE, rFEFE, r7F7F - add rTMP1, rTMP1, r7F7F - nor rWORD, rTMP5, rFEFE - nor rTMP2, rTMP4, rTMP1 - cntlzw rCLZB, rTMP2 - cmplw rWORD, rTMP2 - bgtlr -#endif - srwi rCLZB, rCLZB, 3 - add rRTN, rSTR, rCLZB - blr - -L(foundit): -#ifdef __LITTLE_ENDIAN__ - addi rTMP1, rTMP5, -1 - andc rTMP1, rTMP1, rTMP5 - cntlzw rCLZB, rTMP1 - subfic rCLZB, rCLZB, 32-7-32 - srawi rCLZB, rCLZB, 3 -#else - and rTMP1, r7F7F, rTMP3 - or rTMP4, r7F7F, rTMP3 - add rTMP1, rTMP1, r7F7F - nor rTMP2, rTMP4, rTMP1 - cntlzw rCLZB, rTMP2 - subi rSTR, rSTR, 4 - srwi rCLZB, rCLZB, 3 -#endif - add rRTN, rSTR, rCLZB - blr -END (strchr) - -weak_alias (strchr, index) -libc_hidden_builtin_def (strchr) |