x86_64: Always use builtin memcpy on gcc 4.3

Jan asked to always use the builtin memcpy on gcc 4.3 mainline because
it should generate better code than the old macro. Let's try it.

Cc: Jan Hubicka <jh@suse.cz>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/asm-x86_64/string.h b/include/asm-x86_64/string.h
index 9505d9f4bead96807357ffee406e2d42aaa41a88..e583da7918fb314b34fe8156dd1b7626fbeadf4d 100644 (file)
--- a/include/asm-x86_64/string.h
+++ b/include/asm-x86_64/string.h
@@ -29,6 +29,9 @@ return (to);
    function. */
 
 #define __HAVE_ARCH_MEMCPY 1
+#if (__GNUC__ == 4 && __GNUC_MINOR__ >= 3) || __GNUC__ > 4
+extern void *memcpy(void *to, const void *from, size_t len);
+#else
 extern void *__memcpy(void *to, const void *from, size_t len); 
 #define memcpy(dst,src,len) \
        ({ size_t __len = (len);                                \
@@ -38,7 +41,7 @@ extern void *__memcpy(void *to, const void *from, size_t len);
           else                                                 \
                 __ret = __builtin_memcpy((dst),(src),__len);   \
           __ret; }) 
-
+#endif
 
 #define __HAVE_ARCH_MEMSET
 void *memset(void *s, int c, size_t n);