kernel_optimize_test/include/asm-x86_64/string.h
Andi Kleen aac57f81eb 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>
2007-07-21 18:37:08 -07:00

61 lines
1.5 KiB
C

#ifndef _X86_64_STRING_H_
#define _X86_64_STRING_H_
#ifdef __KERNEL__
/* Written 2002 by Andi Kleen */
/* Only used for special circumstances. Stolen from i386/string.h */
static __always_inline void *
__inline_memcpy(void * to, const void * from, size_t n)
{
unsigned long d0, d1, d2;
__asm__ __volatile__(
"rep ; movsl\n\t"
"testb $2,%b4\n\t"
"je 1f\n\t"
"movsw\n"
"1:\ttestb $1,%b4\n\t"
"je 2f\n\t"
"movsb\n"
"2:"
: "=&c" (d0), "=&D" (d1), "=&S" (d2)
:"0" (n/4), "q" (n),"1" ((long) to),"2" ((long) from)
: "memory");
return (to);
}
/* Even with __builtin_ the compiler may decide to use the out of line
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); \
void *__ret; \
if (__builtin_constant_p(len) && __len >= 64) \
__ret = __memcpy((dst),(src),__len); \
else \
__ret = __builtin_memcpy((dst),(src),__len); \
__ret; })
#endif
#define __HAVE_ARCH_MEMSET
void *memset(void *s, int c, size_t n);
#define __HAVE_ARCH_MEMMOVE
void * memmove(void * dest,const void *src,size_t count);
int memcmp(const void * cs,const void * ct,size_t count);
size_t strlen(const char * s);
char *strcpy(char * dest,const char *src);
char *strcat(char * dest, const char * src);
int strcmp(const char * cs,const char * ct);
#endif /* __KERNEL__ */
#endif