xref: /openbmc/linux/arch/x86/include/asm/string_64.h (revision 588b48ca)
1 #ifndef _ASM_X86_STRING_64_H
2 #define _ASM_X86_STRING_64_H
3 
4 #ifdef __KERNEL__
5 
6 /* Written 2002 by Andi Kleen */
7 
8 /* Only used for special circumstances. Stolen from i386/string.h */
9 static __always_inline void *__inline_memcpy(void *to, const void *from, size_t n)
10 {
11 	unsigned long d0, d1, d2;
12 	asm volatile("rep ; movsl\n\t"
13 		     "testb $2,%b4\n\t"
14 		     "je 1f\n\t"
15 		     "movsw\n"
16 		     "1:\ttestb $1,%b4\n\t"
17 		     "je 2f\n\t"
18 		     "movsb\n"
19 		     "2:"
20 		     : "=&c" (d0), "=&D" (d1), "=&S" (d2)
21 		     : "0" (n / 4), "q" (n), "1" ((long)to), "2" ((long)from)
22 		     : "memory");
23 	return to;
24 }
25 
26 /* Even with __builtin_ the compiler may decide to use the out of line
27    function. */
28 
29 #define __HAVE_ARCH_MEMCPY 1
30 #ifndef CONFIG_KMEMCHECK
31 #if (__GNUC__ == 4 && __GNUC_MINOR__ >= 3) || __GNUC__ > 4
32 extern void *memcpy(void *to, const void *from, size_t len);
33 #else
34 extern void *__memcpy(void *to, const void *from, size_t len);
35 #define memcpy(dst, src, len)					\
36 ({								\
37 	size_t __len = (len);					\
38 	void *__ret;						\
39 	if (__builtin_constant_p(len) && __len >= 64)		\
40 		__ret = __memcpy((dst), (src), __len);		\
41 	else							\
42 		__ret = __builtin_memcpy((dst), (src), __len);	\
43 	__ret;							\
44 })
45 #endif
46 #else
47 /*
48  * kmemcheck becomes very happy if we use the REP instructions unconditionally,
49  * because it means that we know both memory operands in advance.
50  */
51 #define memcpy(dst, src, len) __inline_memcpy((dst), (src), (len))
52 #endif
53 
54 #define __HAVE_ARCH_MEMSET
55 void *memset(void *s, int c, size_t n);
56 
57 #define __HAVE_ARCH_MEMMOVE
58 void *memmove(void *dest, const void *src, size_t count);
59 
60 int memcmp(const void *cs, const void *ct, size_t count);
61 size_t strlen(const char *s);
62 char *strcpy(char *dest, const char *src);
63 char *strcat(char *dest, const char *src);
64 int strcmp(const char *cs, const char *ct);
65 
66 #endif /* __KERNEL__ */
67 
68 #endif /* _ASM_X86_STRING_64_H */
69