/* | |
* memcpy.c | |
*/ | |
#include <string.h> | |
void *memcpy(void *dst, const void *src, size_t n) | |
{ | |
const char *p = src; | |
char *q = dst; | |
#if defined(__i386__) | |
asm volatile("cld ; rep ; movsl ; movl %3,%0 ; rep ; movsb" | |
: "+c" (n >> 2), "+S" (p), "+D" (q) | |
: "r" (n & 3)); | |
#elif defined(__x86_64__) | |
asm volatile("cld ; rep ; movsq ; movl %3,%%ecx ; rep ; movsb" | |
: "+c" (n), "+S" (p), "+D" (q) | |
: "r" ((uint32_t)n & 7)); | |
#else | |
while ( n-- ) { | |
*q++ = *p++; | |
} | |
#endif | |
return dst; | |
} |