PATCH: Add __strend for x86-64

[H.J. Lu]

Hi,

Here is a patch to add an internal function, __strend, for x86-64.

const char *__strlen(const char *s);

It returns a pointer to the end of S, i.e. to the terminating
null-character. It can be used internally in glibc to implement
other string functions.


H.J.
---
2009-07-02  H.J. Lu  <hongjiu.lu@intel.com>

	* sysdeps/x86_64/Makefile (sysdep_routines): Add strend for
	string.

	* sysdeps/x86_64/strlen.S: Don't substract the start of string
	if USE_AS_STREND is defined.

	* sysdeps/x86_64/strend.S: New.

diff --git a/sysdeps/x86_64/Makefile b/sysdeps/x86_64/Makefile
index da82093..7fb6046 100644
--- a/sysdeps/x86_64/Makefile
+++ b/sysdeps/x86_64/Makefile
@@ -11,7 +11,7 @@ sysdep_routines += _mcount
 endif
 
 ifeq ($(subdir),string)
-sysdep_routines += cacheinfo
+sysdep_routines += cacheinfo strend
 endif
 
 ifeq ($(subdir),elf)
diff --git a/sysdeps/x86_64/strend.S b/sysdeps/x86_64/strend.S
new file mode 100644
index 0000000..bd9e3a8
--- /dev/null
+++ b/sysdeps/x86_64/strend.S
@@ -0,0 +1,3 @@
+#define strlen		__strend
+#define USE_AS_STREND
+#include "strlen.S"
diff --git a/sysdeps/x86_64/strlen.S b/sysdeps/x86_64/strlen.S
index 93aee6b..031dd0e 100644
--- a/sysdeps/x86_64/strlen.S
+++ b/sysdeps/x86_64/strlen.S
@@ -25,7 +25,9 @@
 ENTRY(strlen)
 	pxor	%xmm2, %xmm2
 	movq	%rdi, %rcx
+#ifndef USE_AS_STREND
 	movq	%rdi, %r8
+#endif
 	andq	$~15, %rdi
 	movdqa	%xmm2, %xmm1
 	pcmpeqb	(%rdi), %xmm2
@@ -43,9 +45,14 @@ ENTRY(strlen)
 	testl	%edx, %edx
 	jz	2b
 
-1:	subq	%r8, %rdi
+1:
+#ifndef USE_AS_STREND
+	subq	%r8, %rdi
+#endif
 	bsfl	%edx, %eax
 	addq	%rdi, %rax
 	ret
 END(strlen)
+#ifndef USE_AS_STREND
 libc_hidden_builtin_def (strlen)
+#endif