diff options
| author | Ondrej Bilka <neleai@seznam.cz> | 2013-03-18 07:39:12 +0100 |
|---|---|---|
| committer | Ondrej Bilka <neleai@seznam.cz> | 2013-03-18 07:39:12 +0100 |
| commit | 37bb363f03d75e5e6f2ca45f2c686a3a0167797e (patch) | |
| tree | a50f6871e18f34cab50d770bcc730c53364850d5 /sysdeps/x86_64/strnlen.S | |
| parent | f816705060415c476d8a9a0cbb683dc7a5aeef8e (diff) | |
| download | glibc-37bb363f03d75e5e6f2ca45f2c686a3a0167797e.tar.gz glibc-37bb363f03d75e5e6f2ca45f2c686a3a0167797e.tar.xz glibc-37bb363f03d75e5e6f2ca45f2c686a3a0167797e.zip | |
Faster strlen on x64.
Diffstat (limited to 'sysdeps/x86_64/strnlen.S')
| -rw-r--r-- | sysdeps/x86_64/strnlen.S | 67 |
1 files changed, 5 insertions, 62 deletions
diff --git a/sysdeps/x86_64/strnlen.S b/sysdeps/x86_64/strnlen.S index 6e53503060..d3c43ac482 100644 --- a/sysdeps/x86_64/strnlen.S +++ b/sysdeps/x86_64/strnlen.S @@ -1,63 +1,6 @@ -/* strnlen(str,maxlen) -- determine the length of the string STR up to MAXLEN. - Copyright (C) 2010-2013 Free Software Foundation, Inc. - Contributed by Ulrich Drepper <drepper@redhat.com>. - This file is part of the GNU C Library. +#define AS_STRNLEN +#define strlen __strnlen +#include "strlen.S" - 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) +weak_alias (__strnlen, strnlen); +libc_hidden_builtin_def (strnlen) |