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string_64.h
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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 */