LXR linux/arch/x86/include/asm/string

   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 */
   9static __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
  32extern void *memcpy(void *to, const void *from, size_t len);
  33#else
  34extern 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
  55void *memset(void *s, int c, size_t n);
  56
  57#define __HAVE_ARCH_MEMMOVE
  58void *memmove(void *dest, const void *src, size_t count);
  59
  60int memcmp(const void *cs, const void *ct, size_t count);
  61size_t strlen(const char *s);
  62char *strcpy(char *dest, const char *src);
  63char *strcat(char *dest, const char *src);
  64int strcmp(const char *cs, const char *ct);
  65
  66#endif /* __KERNEL__ */
  67
  68#endif /* _ASM_X86_STRING_64_H */
  69