diff options
Diffstat (limited to 'sysdeps/powerpc/powerpc32/power7/strlen.S')
| -rw-r--r-- | sysdeps/powerpc/powerpc32/power7/strlen.S | 102 |
1 files changed, 0 insertions, 102 deletions
diff --git a/sysdeps/powerpc/powerpc32/power7/strlen.S b/sysdeps/powerpc/powerpc32/power7/strlen.S deleted file mode 100644 index 3699791fa6..0000000000 --- a/sysdeps/powerpc/powerpc32/power7/strlen.S +++ /dev/null @@ -1,102 +0,0 @@ -/* Optimized strlen 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] strlen (char *s [r3]) */ - .machine power7 -ENTRY (strlen) - CALL_MCOUNT - dcbt 0,r3 - clrrwi r4,r3,2 /* Align the address to word boundary. */ - rlwinm r6,r3,3,27,28 /* Calculate padding. */ - li r0,0 /* Word with null chars to use with cmpb. */ - li r5,-1 /* MASK = 0xffffffffffffffff. */ - lwz r12,0(r4) /* Load word from memory. */ -#ifdef __LITTLE_ENDIAN__ - slw r5,r5,r6 -#else - srw r5,r5,r6 /* MASK = MASK >> padding. */ -#endif - orc r9,r12,r5 /* Mask bits that are not part of the string. */ - cmpb r10,r9,r0 /* Check for null bytes in WORD1. */ - cmpwi cr7,r10,0 /* If r10 == 0, no null's have been found. */ - bne cr7,L(done) - - mtcrf 0x01,r4 - - /* 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(r4) - cmpb r10,r12,r0 - cmpwi cr7,r10,0 - bne cr7,L(done) - - /* 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): - /* 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(r4) - lwzu r11, 8(r4) - cmpb r10,r12,r0 - cmpb r9,r11,r0 - or r8,r9,r10 /* Merge everything in one word. */ - cmpwi cr7,r8,0 - beq cr7,L(loop) - - /* 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,r10,0 - addi r4,r4,-4 - bne cr6,L(done) - - /* 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 - length. */ - - mr r10,r9 - addi r4,r4,4 - - /* r10 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 length. */ -L(done): -#ifdef __LITTLE_ENDIAN__ - addi r9, r10, -1 /* Form a mask from trailing zeros. */ - andc r9, r9, r10 - popcntw r0, r9 /* Count the bits in the mask. */ -#else - cntlzw r0,r10 /* Count leading zeros before the match. */ -#endif - subf r5,r3,r4 - srwi r0,r0,3 /* Convert leading zeros to bytes. */ - add r3,r5,r0 /* Compute final length. */ - blr -END (strlen) -libc_hidden_builtin_def (strlen) |