mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-03 10:21:05 +00:00
129 lines
3.3 KiB
ArmAsm
129 lines
3.3 KiB
ArmAsm
/* Optimized memcmp implementation for PowerPC476.
|
|
Copyright (C) 2010-2014 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>
|
|
|
|
/* memcmp
|
|
|
|
r3:source1 address, return equality
|
|
r4:source2 address
|
|
r5:byte count
|
|
|
|
Check 2 words from src1 and src2. If unequal jump to end and
|
|
return src1 > src2 or src1 < src2.
|
|
If count = zero check bytes before zero counter and then jump to end and
|
|
return src1 > src2, src1 < src2 or src1 = src2.
|
|
If src1 = src2 and no null, repeat. */
|
|
|
|
EALIGN (memcmp, 5, 0)
|
|
srwi. r6,r5,5
|
|
beq L(preword2_count_loop)
|
|
mtctr r6
|
|
clrlwi r5,r5,27
|
|
|
|
L(word8_compare_loop):
|
|
lwz r10,0(r3)
|
|
lwz r6,4(r3)
|
|
lwz r8,0(r4)
|
|
lwz r9,4(r4)
|
|
cmplw cr5,r8,r10
|
|
cmplw cr1,r9,r6
|
|
bne cr5,L(st2)
|
|
bne cr1,L(st1)
|
|
lwz r10,8(r3)
|
|
lwz r6,12(r3)
|
|
lwz r8,8(r4)
|
|
lwz r9,12(r4)
|
|
cmplw cr5,r8,r10
|
|
cmplw cr1,r9,r6
|
|
bne cr5,L(st2)
|
|
bne cr1,L(st1)
|
|
lwz r10,16(r3)
|
|
lwz r6,20(r3)
|
|
lwz r8,16(r4)
|
|
lwz r9,20(r4)
|
|
cmplw cr5,r8,r10
|
|
cmplw cr1,r9,r6
|
|
bne cr5,L(st2)
|
|
bne cr1,L(st1)
|
|
lwz r10,24(r3)
|
|
lwz r6,28(r3)
|
|
addi r3,r3,0x20
|
|
lwz r8,24(r4)
|
|
lwz r9,28(r4)
|
|
addi r4,r4,0x20
|
|
cmplw cr5,r8,r10
|
|
cmplw cr1,r9,r6
|
|
bne cr5,L(st2)
|
|
bne cr1,L(st1)
|
|
bdnz L(word8_compare_loop)
|
|
|
|
L(preword2_count_loop):
|
|
srwi. r6,r5,3
|
|
beq L(prebyte_count_loop)
|
|
mtctr r6
|
|
clrlwi r5,r5,29
|
|
|
|
L(word2_count_loop):
|
|
lwz r10,0(r3)
|
|
lwz r6,4(r3)
|
|
addi r3,r3,0x08
|
|
lwz r8,0(r4)
|
|
lwz r9,4(r4)
|
|
addi r4,r4,0x08
|
|
cmplw cr5,r8,r10
|
|
cmplw cr1,r9,r6
|
|
bne cr5,L(st2)
|
|
bne cr1,L(st1)
|
|
bdnz L(word2_count_loop)
|
|
|
|
L(prebyte_count_loop):
|
|
addi r5,r5,1
|
|
mtctr r5
|
|
bdz L(end_memcmp)
|
|
|
|
L(byte_count_loop):
|
|
lbz r6,0(r3)
|
|
addi r3,r3,0x01
|
|
lbz r8,0(r4)
|
|
addi r4,r4,0x01
|
|
cmplw cr5,r8,r6
|
|
bne cr5,L(st2)
|
|
bdnz L(byte_count_loop)
|
|
|
|
L(end_memcmp):
|
|
addi r3,r0,0
|
|
blr
|
|
|
|
L(l_r):
|
|
addi r3,r0,1
|
|
blr
|
|
|
|
L(st1):
|
|
blt cr1,L(l_r)
|
|
addi r3,r0,-1
|
|
blr
|
|
|
|
L(st2):
|
|
blt cr5,L(l_r)
|
|
addi r3,r0,-1
|
|
blr
|
|
END (memcmp)
|
|
libc_hidden_builtin_def (memcmp)
|
|
weak_alias (memcmp,bcmp)
|