/* strchr (str, ch) -- Return pointer to first occurrence of CH in STR.
For AMD x86-64.
Copyright (C) 2009-2016 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
. */
#include
.text
ENTRY (strchr)
movd %esi, %xmm1
movl %edi, %eax
andl $4095, %eax
punpcklbw %xmm1, %xmm1
cmpl $4032, %eax
punpcklwd %xmm1, %xmm1
pshufd $0, %xmm1, %xmm1
jg L(cross_page)
movdqu (%rdi), %xmm0
pxor %xmm3, %xmm3
movdqa %xmm0, %xmm4
pcmpeqb %xmm1, %xmm0
pcmpeqb %xmm3, %xmm4
por %xmm4, %xmm0
pmovmskb %xmm0, %eax
test %eax, %eax
je L(next_48_bytes)
bsf %eax, %eax
#ifdef AS_STRCHRNUL
leaq (%rdi,%rax), %rax
#else
movl $0, %edx
leaq (%rdi,%rax), %rax
cmpb %sil, (%rax)
cmovne %rdx, %rax
#endif
ret
.p2align 3
L(next_48_bytes):
movdqu 16(%rdi), %xmm0
movdqa %xmm0, %xmm4
pcmpeqb %xmm1, %xmm0
pcmpeqb %xmm3, %xmm4
por %xmm4, %xmm0
pmovmskb %xmm0, %ecx
movdqu 32(%rdi), %xmm0
movdqa %xmm0, %xmm4
pcmpeqb %xmm1, %xmm0
salq $16, %rcx
pcmpeqb %xmm3, %xmm4
por %xmm4, %xmm0
pmovmskb %xmm0, %eax
movdqu 48(%rdi), %xmm0
pcmpeqb %xmm0, %xmm3
salq $32, %rax
pcmpeqb %xmm1, %xmm0
orq %rcx, %rax
por %xmm3, %xmm0
pmovmskb %xmm0, %ecx
salq $48, %rcx
orq %rcx, %rax
testq %rax, %rax
jne L(return)
L(loop_start):
/* We use this alignment to force loop be aligned to 8 but not
16 bytes. This gives better sheduling on AMD processors. */
.p2align 4
pxor %xmm6, %xmm6
andq $-64, %rdi
.p2align 3
L(loop64):
addq $64, %rdi
movdqa (%rdi), %xmm5
movdqa 16(%rdi), %xmm2
movdqa 32(%rdi), %xmm3
pxor %xmm1, %xmm5
movdqa 48(%rdi), %xmm4
pxor %xmm1, %xmm2
pxor %xmm1, %xmm3
pminub (%rdi), %xmm5
pxor %xmm1, %xmm4
pminub 16(%rdi), %xmm2
pminub 32(%rdi), %xmm3
pminub %xmm2, %xmm5
pminub 48(%rdi), %xmm4
pminub %xmm3, %xmm5
pminub %xmm4, %xmm5
pcmpeqb %xmm6, %xmm5
pmovmskb %xmm5, %eax
testl %eax, %eax
je L(loop64)
movdqa (%rdi), %xmm5
movdqa %xmm5, %xmm0
pcmpeqb %xmm1, %xmm5
pcmpeqb %xmm6, %xmm0
por %xmm0, %xmm5
pcmpeqb %xmm6, %xmm2
pcmpeqb %xmm6, %xmm3
pcmpeqb %xmm6, %xmm4
pmovmskb %xmm5, %ecx
pmovmskb %xmm2, %eax
salq $16, %rax
pmovmskb %xmm3, %r8d
pmovmskb %xmm4, %edx
salq $32, %r8
orq %r8, %rax
orq %rcx, %rax
salq $48, %rdx
orq %rdx, %rax
.p2align 3
L(return):
bsfq %rax, %rax
#ifdef AS_STRCHRNUL
leaq (%rdi,%rax), %rax
#else
movl $0, %edx
leaq (%rdi,%rax), %rax
cmpb %sil, (%rax)
cmovne %rdx, %rax
#endif
ret
.p2align 4
L(cross_page):
movq %rdi, %rdx
pxor %xmm2, %xmm2
andq $-64, %rdx
movdqa %xmm1, %xmm0
movdqa (%rdx), %xmm3
movdqa %xmm3, %xmm4
pcmpeqb %xmm1, %xmm3
pcmpeqb %xmm2, %xmm4
por %xmm4, %xmm3
pmovmskb %xmm3, %r8d
movdqa 16(%rdx), %xmm3
movdqa %xmm3, %xmm4
pcmpeqb %xmm1, %xmm3
pcmpeqb %xmm2, %xmm4
por %xmm4, %xmm3
pmovmskb %xmm3, %eax
movdqa 32(%rdx), %xmm3
movdqa %xmm3, %xmm4
pcmpeqb %xmm1, %xmm3
salq $16, %rax
pcmpeqb %xmm2, %xmm4
por %xmm4, %xmm3
pmovmskb %xmm3, %r9d
movdqa 48(%rdx), %xmm3
pcmpeqb %xmm3, %xmm2
salq $32, %r9
pcmpeqb %xmm3, %xmm0
orq %r9, %rax
orq %r8, %rax
por %xmm2, %xmm0
pmovmskb %xmm0, %ecx
salq $48, %rcx
orq %rcx, %rax
movl %edi, %ecx
subb %dl, %cl
shrq %cl, %rax
testq %rax, %rax
jne L(return)
jmp L(loop_start)
END (strchr)
#ifndef AS_STRCHRNUL
weak_alias (strchr, index)
libc_hidden_builtin_def (strchr)
#endif