diff options
Diffstat (limited to 'sysdeps/x86_64/memchr.S')
-rw-r--r-- | sysdeps/x86_64/memchr.S | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/sysdeps/x86_64/memchr.S b/sysdeps/x86_64/memchr.S new file mode 100644 index 0000000000..15484cb9f3 --- /dev/null +++ b/sysdeps/x86_64/memchr.S @@ -0,0 +1,67 @@ +/* strlen(str) -- determine the length of the string STR. + Copyright (C) 2009 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 (memchr) + movd %esi, %xmm1 + movq %rdi, %rcx + punpcklbw %xmm1, %xmm1 + andq $~15, %rdi + punpcklbw %xmm1, %xmm1 + orl $0xffffffff, %esi + movdqa (%rdi), %xmm0 + pshufd $0, %xmm1, %xmm1 + subq %rdi, %rcx + pcmpeqb %xmm1, %xmm0 + addq %rcx, %rdx + shl %cl, %esi + pmovmskb %xmm0, %ecx + andl %esi, %ecx + movl $0, %esi + jnz 1f + cmpq %rsi, %rdx + jle 3f + +2: movdqa 16(%rdi,%rsi), %xmm0 + leaq 16(%rsi), %rsi + pcmpeqb %xmm1, %xmm0 + pmovmskb %xmm0, %ecx + testl %ecx, %ecx + jnz 1f + cmpq %rsi, %rdx + jg 2b + +3: xorl %eax, %eax + ret + +1: leaq (%rdi,%rsi), %rax + bsfl %ecx, %ecx + addq %rcx, %rax + addq %rcx, %rsi + cmpq %rsi, %rdx + jle 3b + ret +END (memchr) + +strong_alias (memchr, __memchr) +libc_hidden_builtin_def (memchr) |