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/* Optimized memrchr with sse2
Copyright (C) 2011-2023 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
<https://www.gnu.org/licenses/>. */
#if IS_IN (libc)
# include <sysdep.h>
# define CFI_PUSH(REG) \
cfi_adjust_cfa_offset (4); \
cfi_rel_offset (REG, 0)
# define CFI_POP(REG) \
cfi_adjust_cfa_offset (-4); \
cfi_restore (REG)
# define PUSH(REG) pushl REG; CFI_PUSH (REG)
# define POP(REG) popl REG; CFI_POP (REG)
# define PARMS 4
# define STR1 PARMS
# define STR2 STR1+4
# define LEN STR2+4
# define MEMCHR __memrchr_sse2_bsf
.text
ENTRY (MEMCHR)
mov STR1(%esp), %ecx
movd STR2(%esp), %xmm1
mov LEN(%esp), %edx
sub $16, %edx
jbe L(length_less16)
punpcklbw %xmm1, %xmm1
add %edx, %ecx
punpcklbw %xmm1, %xmm1
movdqu (%ecx), %xmm0
pshufd $0, %xmm1, %xmm1
pcmpeqb %xmm1, %xmm0
/* Check if there is a match. */
pmovmskb %xmm0, %eax
test %eax, %eax
jnz L(matches0)
sub $64, %ecx
mov %ecx, %eax
and $15, %eax
jz L(loop_prolog)
add $16, %ecx
add $16, %edx
sub %eax, %ecx
sub %eax, %edx
.p2align 4
/* Loop start on aligned string. */
L(loop_prolog):
sub $64, %edx
jbe L(exit_loop)
movdqa 48(%ecx), %xmm0
pcmpeqb %xmm1, %xmm0
pmovmskb %xmm0, %eax
test %eax, %eax
jnz L(matches48)
movdqa 32(%ecx), %xmm2
pcmpeqb %xmm1, %xmm2
pmovmskb %xmm2, %eax
test %eax, %eax
jnz L(matches32)
movdqa 16(%ecx), %xmm3
pcmpeqb %xmm1, %xmm3
pmovmskb %xmm3, %eax
test %eax, %eax
jnz L(matches16)
movdqa (%ecx), %xmm4
pcmpeqb %xmm1, %xmm4
pmovmskb %xmm4, %eax
test %eax, %eax
jnz L(matches0)
sub $64, %ecx
sub $64, %edx
jbe L(exit_loop)
movdqa 48(%ecx), %xmm0
pcmpeqb %xmm1, %xmm0
pmovmskb %xmm0, %eax
test %eax, %eax
jnz L(matches48)
movdqa 32(%ecx), %xmm2
pcmpeqb %xmm1, %xmm2
pmovmskb %xmm2, %eax
test %eax, %eax
jnz L(matches32)
movdqa 16(%ecx), %xmm3
pcmpeqb %xmm1, %xmm3
pmovmskb %xmm3, %eax
test %eax, %eax
jnz L(matches16)
movdqa (%ecx), %xmm3
pcmpeqb %xmm1, %xmm3
pmovmskb %xmm3, %eax
test %eax, %eax
jnz L(matches0)
mov %ecx, %eax
and $63, %eax
test %eax, %eax
jz L(align64_loop)
add $64, %ecx
add $64, %edx
sub %eax, %ecx
sub %eax, %edx
.p2align 4
L(align64_loop):
sub $64, %ecx
sub $64, %edx
jbe L(exit_loop)
movdqa (%ecx), %xmm0
movdqa 16(%ecx), %xmm2
movdqa 32(%ecx), %xmm3
movdqa 48(%ecx), %xmm4
pcmpeqb %xmm1, %xmm0
pcmpeqb %xmm1, %xmm2
pcmpeqb %xmm1, %xmm3
pcmpeqb %xmm1, %xmm4
pmaxub %xmm3, %xmm0
pmaxub %xmm4, %xmm2
pmaxub %xmm0, %xmm2
pmovmskb %xmm2, %eax
test %eax, %eax
jz L(align64_loop)
pmovmskb %xmm4, %eax
test %eax, %eax
jnz L(matches48)
pmovmskb %xmm3, %eax
test %eax, %eax
jnz L(matches32)
movdqa 16(%ecx), %xmm2
pcmpeqb %xmm1, %xmm2
pcmpeqb (%ecx), %xmm1
pmovmskb %xmm2, %eax
test %eax, %eax
jnz L(matches16)
pmovmskb %xmm1, %eax
bsr %eax, %eax
add %ecx, %eax
ret
.p2align 4
L(exit_loop):
add $64, %edx
cmp $32, %edx
jbe L(exit_loop_32)
movdqa 48(%ecx), %xmm0
pcmpeqb %xmm1, %xmm0
pmovmskb %xmm0, %eax
test %eax, %eax
jnz L(matches48)
movdqa 32(%ecx), %xmm2
pcmpeqb %xmm1, %xmm2
pmovmskb %xmm2, %eax
test %eax, %eax
jnz L(matches32)
movdqa 16(%ecx), %xmm3
pcmpeqb %xmm1, %xmm3
pmovmskb %xmm3, %eax
test %eax, %eax
jnz L(matches16_1)
cmp $48, %edx
jbe L(return_null)
pcmpeqb (%ecx), %xmm1
pmovmskb %xmm1, %eax
test %eax, %eax
jnz L(matches0_1)
xor %eax, %eax
ret
.p2align 4
L(exit_loop_32):
movdqa 48(%ecx), %xmm0
pcmpeqb %xmm1, %xmm0
pmovmskb %xmm0, %eax
test %eax, %eax
jnz L(matches48_1)
cmp $16, %edx
jbe L(return_null)
pcmpeqb 32(%ecx), %xmm1
pmovmskb %xmm1, %eax
test %eax, %eax
jnz L(matches32_1)
xor %eax, %eax
ret
.p2align 4
L(matches0):
bsr %eax, %eax
add %ecx, %eax
ret
.p2align 4
L(matches16):
bsr %eax, %eax
lea 16(%eax, %ecx), %eax
ret
.p2align 4
L(matches32):
bsr %eax, %eax
lea 32(%eax, %ecx), %eax
ret
.p2align 4
L(matches48):
bsr %eax, %eax
lea 48(%eax, %ecx), %eax
ret
.p2align 4
L(matches0_1):
bsr %eax, %eax
sub $64, %edx
add %eax, %edx
jl L(return_null)
add %ecx, %eax
ret
.p2align 4
L(matches16_1):
bsr %eax, %eax
sub $48, %edx
add %eax, %edx
jl L(return_null)
lea 16(%ecx, %eax), %eax
ret
.p2align 4
L(matches32_1):
bsr %eax, %eax
sub $32, %edx
add %eax, %edx
jl L(return_null)
lea 32(%ecx, %eax), %eax
ret
.p2align 4
L(matches48_1):
bsr %eax, %eax
sub $16, %edx
add %eax, %edx
jl L(return_null)
lea 48(%ecx, %eax), %eax
ret
.p2align 4
L(return_null):
xor %eax, %eax
ret
.p2align 4
L(length_less16_offset0):
mov %dl, %cl
pcmpeqb (%eax), %xmm1
mov $1, %edx
sal %cl, %edx
sub $1, %edx
mov %edx, %ecx
pmovmskb %xmm1, %edx
and %ecx, %edx
test %edx, %edx
jz L(return_null)
bsr %edx, %ecx
add %ecx, %eax
ret
.p2align 4
L(length_less16):
punpcklbw %xmm1, %xmm1
mov %ecx, %eax
punpcklbw %xmm1, %xmm1
add $16, %edx
jz L(return_null)
pshufd $0, %xmm1, %xmm1
and $15, %ecx
jz L(length_less16_offset0)
PUSH (%edi)
mov %cl, %dh
add %dl, %dh
and $-16, %eax
sub $16, %dh
ja L(length_less16_part2)
pcmpeqb (%eax), %xmm1
pmovmskb %xmm1, %edi
sar %cl, %edi
add %ecx, %eax
mov %dl, %cl
mov $1, %edx
sal %cl, %edx
sub $1, %edx
and %edx, %edi
test %edi, %edi
jz L(ret_null)
bsr %edi, %edi
add %edi, %eax
POP (%edi)
ret
CFI_PUSH (%edi)
.p2align 4
L(length_less16_part2):
movdqa 16(%eax), %xmm2
pcmpeqb %xmm1, %xmm2
pmovmskb %xmm2, %edi
mov %cl, %ch
mov %dh, %cl
mov $1, %edx
sal %cl, %edx
sub $1, %edx
and %edx, %edi
test %edi, %edi
jnz L(length_less16_part2_return)
pcmpeqb (%eax), %xmm1
pmovmskb %xmm1, %edi
mov %ch, %cl
sar %cl, %edi
test %edi, %edi
jz L(ret_null)
bsr %edi, %edi
add %edi, %eax
xor %ch, %ch
add %ecx, %eax
POP (%edi)
ret
CFI_PUSH (%edi)
.p2align 4
L(length_less16_part2_return):
bsr %edi, %edi
lea 16(%eax, %edi), %eax
POP (%edi)
ret
CFI_PUSH (%edi)
.p2align 4
L(ret_null):
xor %eax, %eax
POP (%edi)
ret
END (MEMCHR)
#endif
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