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/*
* memmove.c
*/
#include <string.h>
void *memmove(void *dst, const void *src, size_t n)
{
const char *p = src;
char *q = dst;
#if defined(__i386__) || defined(__x86_64__)
if (q < p) {
asm volatile("cld; rep; movsb"
: "+c" (n), "+S"(p), "+D"(q));
} else {
p += (n - 1);
q += (n - 1);
asm volatile("std; rep; movsb; cld"
: "+c" (n), "+S"(p), "+D"(q));
}
#else
if (q < p) {
while (n--) {
*q++ = *p++;
}
} else {
p += n;
q += n;
while (n--) {
*--q = *--p;
}
}
#endif
return dst;
}
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