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/* strnlen(str,maxlen) -- determine the length of the string STR up to MAXLEN.
Copyright (C) 2010 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>
.text
ENTRY(__strnlen)
movq %rsi, %rax
testq %rsi, %rsi
jz 3f
pxor %xmm2, %xmm2
movq %rdi, %rcx
movq %rdi, %r8
movq $16, %r9
andq $~15, %rdi
movdqa %xmm2, %xmm1
pcmpeqb (%rdi), %xmm2
orl $0xffffffff, %r10d
subq %rdi, %rcx
shll %cl, %r10d
subq %rcx, %r9
pmovmskb %xmm2, %edx
andl %r10d, %edx
jnz 1f
subq %r9, %rsi
jbe 3f
2: movdqa 16(%rdi), %xmm0
leaq 16(%rdi), %rdi
pcmpeqb %xmm1, %xmm0
pmovmskb %xmm0, %edx
testl %edx, %edx
jnz 1f
subq $16, %rsi
jnbe 2b
3: ret
1: subq %r8, %rdi
bsfl %edx, %edx
addq %rdi, %rdx
cmpq %rdx, %rax
cmovnbq %rdx, %rax
ret
END(__strnlen)
weak_alias (__strnlen, strnlen)
libc_hidden_def (strnlen)
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