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/* strchr SSE2 without bsf
Copyright (C) 2011-2024 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 8
# define ENTRANCE PUSH(%edi)
# define RETURN POP(%edi); ret; CFI_PUSH(%edi);
# define STR1 PARMS
# define STR2 STR1+4
atom_text_section
ENTRY (__strchr_sse2)
ENTRANCE
mov STR1(%esp), %ecx
movd STR2(%esp), %xmm1
pxor %xmm2, %xmm2
mov %ecx, %edi
punpcklbw %xmm1, %xmm1
punpcklbw %xmm1, %xmm1
/* ECX has OFFSET. */
and $15, %ecx
pshufd $0, %xmm1, %xmm1
je L(loop)
/* Handle unaligned string. */
and $-16, %edi
movdqa (%edi), %xmm0
pcmpeqb %xmm0, %xmm2
pcmpeqb %xmm1, %xmm0
/* Find where NULL is. */
pmovmskb %xmm2, %edx
/* Check if there is a match. */
pmovmskb %xmm0, %eax
/* Remove the leading bytes. */
sarl %cl, %edx
sarl %cl, %eax
test %eax, %eax
jz L(unaligned_no_match)
/* Check which byte is a match. */
/* Is there a NULL? */
add %ecx, %edi
test %edx, %edx
jz L(match_case1)
jmp L(match_case2)
.p2align 4
L(unaligned_no_match):
test %edx, %edx
jne L(return_null)
pxor %xmm2, %xmm2
add $16, %edi
.p2align 4
/* Loop start on aligned string. */
L(loop):
movdqa (%edi), %xmm0
pcmpeqb %xmm0, %xmm2
pcmpeqb %xmm1, %xmm0
pmovmskb %xmm2, %edx
pmovmskb %xmm0, %eax
test %eax, %eax
jnz L(matches)
test %edx, %edx
jnz L(return_null)
add $16, %edi
movdqa (%edi), %xmm0
pcmpeqb %xmm0, %xmm2
pcmpeqb %xmm1, %xmm0
pmovmskb %xmm2, %edx
pmovmskb %xmm0, %eax
test %eax, %eax
jnz L(matches)
test %edx, %edx
jnz L(return_null)
add $16, %edi
movdqa (%edi), %xmm0
pcmpeqb %xmm0, %xmm2
pcmpeqb %xmm1, %xmm0
pmovmskb %xmm2, %edx
pmovmskb %xmm0, %eax
test %eax, %eax
jnz L(matches)
test %edx, %edx
jnz L(return_null)
add $16, %edi
movdqa (%edi), %xmm0
pcmpeqb %xmm0, %xmm2
pcmpeqb %xmm1, %xmm0
pmovmskb %xmm2, %edx
pmovmskb %xmm0, %eax
test %eax, %eax
jnz L(matches)
test %edx, %edx
jnz L(return_null)
add $16, %edi
jmp L(loop)
L(matches):
/* There is a match. First find where NULL is. */
test %edx, %edx
jz L(match_case1)
.p2align 4
L(match_case2):
test %al, %al
jz L(match_higth_case2)
mov %al, %cl
and $15, %cl
jnz L(match_case2_4)
mov %dl, %ch
and $15, %ch
jnz L(return_null)
test $0x10, %al
jnz L(Exit5)
test $0x10, %dl
jnz L(return_null)
test $0x20, %al
jnz L(Exit6)
test $0x20, %dl
jnz L(return_null)
test $0x40, %al
jnz L(Exit7)
test $0x40, %dl
jnz L(return_null)
lea 7(%edi), %eax
RETURN
.p2align 4
L(match_case2_4):
test $0x01, %al
jnz L(Exit1)
test $0x01, %dl
jnz L(return_null)
test $0x02, %al
jnz L(Exit2)
test $0x02, %dl
jnz L(return_null)
test $0x04, %al
jnz L(Exit3)
test $0x04, %dl
jnz L(return_null)
lea 3(%edi), %eax
RETURN
.p2align 4
L(match_higth_case2):
test %dl, %dl
jnz L(return_null)
mov %ah, %cl
and $15, %cl
jnz L(match_case2_12)
mov %dh, %ch
and $15, %ch
jnz L(return_null)
test $0x10, %ah
jnz L(Exit13)
test $0x10, %dh
jnz L(return_null)
test $0x20, %ah
jnz L(Exit14)
test $0x20, %dh
jnz L(return_null)
test $0x40, %ah
jnz L(Exit15)
test $0x40, %dh
jnz L(return_null)
lea 15(%edi), %eax
RETURN
.p2align 4
L(match_case2_12):
test $0x01, %ah
jnz L(Exit9)
test $0x01, %dh
jnz L(return_null)
test $0x02, %ah
jnz L(Exit10)
test $0x02, %dh
jnz L(return_null)
test $0x04, %ah
jnz L(Exit11)
test $0x04, %dh
jnz L(return_null)
lea 11(%edi), %eax
RETURN
.p2align 4
L(match_case1):
test %al, %al
jz L(match_higth_case1)
test $0x01, %al
jnz L(Exit1)
test $0x02, %al
jnz L(Exit2)
test $0x04, %al
jnz L(Exit3)
test $0x08, %al
jnz L(Exit4)
test $0x10, %al
jnz L(Exit5)
test $0x20, %al
jnz L(Exit6)
test $0x40, %al
jnz L(Exit7)
lea 7(%edi), %eax
RETURN
.p2align 4
L(match_higth_case1):
test $0x01, %ah
jnz L(Exit9)
test $0x02, %ah
jnz L(Exit10)
test $0x04, %ah
jnz L(Exit11)
test $0x08, %ah
jnz L(Exit12)
test $0x10, %ah
jnz L(Exit13)
test $0x20, %ah
jnz L(Exit14)
test $0x40, %ah
jnz L(Exit15)
lea 15(%edi), %eax
RETURN
.p2align 4
L(Exit1):
lea (%edi), %eax
RETURN
.p2align 4
L(Exit2):
lea 1(%edi), %eax
RETURN
.p2align 4
L(Exit3):
lea 2(%edi), %eax
RETURN
.p2align 4
L(Exit4):
lea 3(%edi), %eax
RETURN
.p2align 4
L(Exit5):
lea 4(%edi), %eax
RETURN
.p2align 4
L(Exit6):
lea 5(%edi), %eax
RETURN
.p2align 4
L(Exit7):
lea 6(%edi), %eax
RETURN
.p2align 4
L(Exit9):
lea 8(%edi), %eax
RETURN
.p2align 4
L(Exit10):
lea 9(%edi), %eax
RETURN
.p2align 4
L(Exit11):
lea 10(%edi), %eax
RETURN
.p2align 4
L(Exit12):
lea 11(%edi), %eax
RETURN
.p2align 4
L(Exit13):
lea 12(%edi), %eax
RETURN
.p2align 4
L(Exit14):
lea 13(%edi), %eax
RETURN
.p2align 4
L(Exit15):
lea 14(%edi), %eax
RETURN
/* Return NULL. */
.p2align 4
L(return_null):
xor %eax, %eax
RETURN
END (__strchr_sse2)
#endif
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