| /* 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, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #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) |
