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Diffstat (limited to 'sysdeps/powerpc/powerpc32/power7/strchr.S')
| -rw-r--r-- | sysdeps/powerpc/powerpc32/power7/strchr.S | 225 |
1 files changed, 0 insertions, 225 deletions
diff --git a/sysdeps/powerpc/powerpc32/power7/strchr.S b/sysdeps/powerpc/powerpc32/power7/strchr.S deleted file mode 100644 index 75ca6acb98..0000000000 --- a/sysdeps/powerpc/powerpc32/power7/strchr.S +++ /dev/null @@ -1,225 +0,0 @@ -/* Optimized strchr implementation for PowerPC32/POWER7 using cmpb insn. - Copyright (C) 2010-2017 Free Software Foundation, Inc. - Contributed by Luis Machado <luisgpm@br.ibm.com>. - 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> - -/* int [r3] strchr (char *s [r3], int c [r4]) */ - .machine power7 -ENTRY (strchr) - CALL_MCOUNT - dcbt 0,r3 - clrrwi r8,r3,2 /* Align the address to word boundary. */ - cmpwi cr7,r4,0 - lwz r12,0(r8) /* Load word from memory. */ - li r0,0 /* Word with null chars to use - with cmpb. */ - - rlwinm r6,r3,3,27,28 /* Calculate padding. */ - - beq cr7,L(null_match) - - /* Replicate byte to word. */ - insrwi r4,r4,8,16 - insrwi r4,r4,16,0 - - /* Now r4 has a word of c bytes and r0 has - a word of null bytes. */ - - cmpb r10,r12,r4 /* Compare each byte against c byte. */ - cmpb r11,r12,r0 /* Compare each byte against null byte. */ - - /* Move the words left and right to discard the bits that are - not part of the string and to bring them back as zeros. */ -#ifdef __LITTLE_ENDIAN__ - srw r10,r10,r6 - srw r11,r11,r6 - slw r10,r10,r6 - slw r11,r11,r6 -#else - slw r10,r10,r6 - slw r11,r11,r6 - srw r10,r10,r6 - srw r11,r11,r6 -#endif - or r5,r10,r11 /* OR the results to speed things up. */ - cmpwi cr7,r5,0 /* If r5 == 0, no c or null bytes - have been found. */ - bne cr7,L(done) - - mtcrf 0x01,r8 - - /* Are we now aligned to a doubleword boundary? If so, skip to - the main loop. Otherwise, go through the alignment code. */ - - bt 29,L(loop) - - /* Handle WORD2 of pair. */ - lwzu r12,4(r8) - cmpb r10,r12,r4 - cmpb r11,r12,r0 - or r5,r10,r11 - cmpwi cr7,r5,0 - bne cr7,L(done) - b L(loop) /* We branch here (rather than falling through) - to skip the nops due to heavy alignment - of the loop below. */ - - .p2align 5 -L(loop): - /* Load two words, compare and merge in a - single register for speed. This is an attempt - to speed up the null-checking process for bigger strings. */ - lwz r12,4(r8) - lwzu r9,8(r8) - cmpb r10,r12,r4 - cmpb r11,r12,r0 - cmpb r6,r9,r4 - cmpb r7,r9,r0 - or r12,r10,r11 - or r9,r6,r7 - or r5,r12,r9 - cmpwi cr7,r5,0 - beq cr7,L(loop) - - /* OK, one (or both) of the words contains a c/null byte. Check - the first word and decrement the address in case the first - word really contains a c/null byte. */ - - cmpwi cr6,r12,0 - addi r8,r8,-4 - bne cr6,L(done) - - /* The c/null byte must be in the second word. Adjust the address - again and move the result of cmpb to r10/r11 so we can calculate - the pointer. */ - - mr r10,r6 - mr r11,r7 - addi r8,r8,4 - - /* r10/r11 have the output of the cmpb instructions, that is, - 0xff in the same position as the c/null byte in the original - word from the string. Use that to calculate the pointer. */ -L(done): -#ifdef __LITTLE_ENDIAN__ - addi r3,r10,-1 - andc r3,r3,r10 - popcntw r0,r3 - addi r4,r11,-1 - andc r4,r4,r11 - cmplw cr7,r3,r4 - bgt cr7,L(no_match) -#else - cntlzw r0,r10 /* Count leading zeros before c matches. */ - cmplw cr7,r11,r10 - bgt cr7,L(no_match) -#endif - srwi r0,r0,3 /* Convert leading zeros to bytes. */ - add r3,r8,r0 /* Return address of the matching c byte - or null in case c was not found. */ - blr - - .align 4 -L(no_match): - li r3,0 - blr - -/* We are here because strchr was called with a null byte. */ - .align 4 -L(null_match): - /* r0 has a word of null bytes. */ - - cmpb r5,r12,r0 /* Compare each byte against null bytes. */ - - /* Move the words left and right to discard the bits that are - not part of the string and bring them back as zeros. */ -#ifdef __LITTLE_ENDIAN__ - srw r5,r5,r6 - slw r5,r5,r6 -#else - slw r5,r5,r6 - srw r5,r5,r6 -#endif - cmpwi cr7,r5,0 /* If r10 == 0, no c or null bytes - have been found. */ - bne cr7,L(done_null) - - mtcrf 0x01,r8 - - /* Are we now aligned to a doubleword boundary? If so, skip to - the main loop. Otherwise, go through the alignment code. */ - - bt 29,L(loop_null) - - /* Handle WORD2 of pair. */ - lwzu r12,4(r8) - cmpb r5,r12,r0 - cmpwi cr7,r5,0 - bne cr7,L(done_null) - b L(loop_null) /* We branch here (rather than falling through) - to skip the nops due to heavy alignment - of the loop below. */ - - /* Main loop to look for the end of the string. Since it's a - small loop (< 8 instructions), align it to 32-bytes. */ - .p2align 5 -L(loop_null): - /* Load two words, compare and merge in a - single register for speed. This is an attempt - to speed up the null-checking process for bigger strings. */ - lwz r12,4(r8) - lwzu r11,8(r8) - cmpb r5,r12,r0 - cmpb r10,r11,r0 - or r6,r5,r10 - cmpwi cr7,r6,0 - beq cr7,L(loop_null) - - /* OK, one (or both) of the words contains a null byte. Check - the first word and decrement the address in case the first - word really contains a null byte. */ - - cmpwi cr6,r5,0 - addi r8,r8,-4 - bne cr6,L(done_null) - - /* The null byte must be in the second word. Adjust the address - again and move the result of cmpb to r10 so we can calculate the - pointer. */ - - mr r5,r10 - addi r8,r8,4 - - /* r5 has the output of the cmpb instruction, that is, it contains - 0xff in the same position as the null byte in the original - word from the string. Use that to calculate the pointer. */ -L(done_null): -#ifdef __LITTLE_ENDIAN__ - addi r0,r5,-1 - andc r0,r0,r5 - popcntw r0,r0 -#else - cntlzw r0,r5 /* Count leading zeros before the match. */ -#endif - srwi r0,r0,3 /* Convert leading zeros to bytes. */ - add r3,r8,r0 /* Return address of the matching null byte. */ - blr -END (strchr) -weak_alias (strchr, index) -libc_hidden_builtin_def (strchr) |