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authorUlrich Drepper <drepper@redhat.com>2009-04-07 06:36:33 +0000
committerUlrich Drepper <drepper@redhat.com>2009-04-07 06:36:33 +0000
commit322e23db2402ceb66d7f7e5f59d07965382f298a (patch)
tree2a55d61c8d422d6cee5781c51e2dc8c96f75dfb9 /sysdeps/x86_64/memchr.S
parentae06191038e8757bc9ba637c7c94f2e02817b43b (diff)
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* sysdeps/x86_64/memchr.S: New file.
Diffstat (limited to 'sysdeps/x86_64/memchr.S')
-rw-r--r--sysdeps/x86_64/memchr.S67
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)