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/* Multiple versions of rawmemchr
All versions must be listed in ifunc-impl-list.c.
Copyright (C) 2009-2012 Free Software Foundation, Inc.
Contributed by Ulrich Drepper <drepper@redhat.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>
#include <init-arch.h>
/* Define multiple versions only for the definition in lib. */
#ifndef NOT_IN_libc
.text
ENTRY(rawmemchr)
.type rawmemchr, @gnu_indirect_function
cmpl $0, __cpu_features+KIND_OFFSET(%rip)
jne 1f
call __init_cpu_features
1: testl $bit_Prefer_PMINUB_for_stringop, __cpu_features+FEATURE_OFFSET+index_Prefer_PMINUB_for_stringop(%rip)
jnz 2f
testl $bit_SSE4_2, __cpu_features+CPUID_OFFSET+index_SSE4_2(%rip)
jz 2f
leaq __rawmemchr_sse42(%rip), %rax
ret
2: leaq __rawmemchr_sse2(%rip), %rax
ret
END(rawmemchr)
strong_alias (rawmemchr, __rawmemchr)
.section .text.sse4.2,"ax",@progbits
.align 16
.type __rawmemchr_sse42, @function
.globl __rawmemchr_sse42
.hidden __rawmemchr_sse42
__rawmemchr_sse42:
cfi_startproc
CALL_MCOUNT
movd %esi, %xmm1
movq %rdi, %rcx
pxor %xmm2, %xmm2
andq $~15, %rdi
orl $0xffffffff, %esi
pshufb %xmm2, %xmm1
movdqa (%rdi), %xmm0
subq %rdi, %rcx
pcmpeqb %xmm1, %xmm0
shl %cl, %esi
pmovmskb %xmm0, %ecx
movl $16, %eax
movl $16, %edx
andl %esi, %ecx
jnz 1f
2: pcmpestri $0x08, 16(%rdi), %xmm1
leaq 16(%rdi), %rdi
jnc 2b
leaq (%rdi,%rcx), %rax
ret
1: bsfl %ecx, %eax
addq %rdi, %rax
ret
cfi_endproc
.size __rawmemchr_sse42, .-__rawmemchr_sse42
# undef ENTRY
# define ENTRY(name) \
.type __rawmemchr_sse2, @function; \
.align 16; \
.globl __rawmemchr_sse2; \
.hidden __rawmemchr_sse2; \
__rawmemchr_sse2: cfi_startproc; \
CALL_MCOUNT
# undef END
# define END(name) \
cfi_endproc; .size __rawmemchr_sse2, .-__rawmemchr_sse2
# undef libc_hidden_builtin_def
/* It doesn't make sense to send libc-internal rawmemchr calls through a PLT.
The speedup we get from using SSE4.2 instruction is likely eaten away
by the indirect call in the PLT. */
# define libc_hidden_builtin_def(name) \
.globl __GI___rawmemchr; __GI___rawmemchr = __rawmemchr_sse2
#endif
#include "../rawmemchr.S"
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