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#include <string.h>
#include <stdlib.h>
#include <stdint.h>
#define SS (sizeof(size_t))
#define ALIGN (sizeof(size_t)-1)
#define ONES ((size_t)-1/UCHAR_MAX)
void *memcpy(void *dest, const void *src, size_t n)
{
unsigned char *d = dest;
const unsigned char *s = src;
if (((uintptr_t)d & ALIGN) != ((uintptr_t)s & ALIGN))
goto misaligned;
for (; ((uintptr_t)d & ALIGN) && n; n--) *d++ = *s++;
if (n) {
size_t *wd = (void *)d;
const size_t *ws = (const void *)s;
for (; n>=SS; n-=SS) *wd++ = *ws++;
d = (void *)wd;
s = (const void *)ws;
misaligned:
for (; n; n--) *d++ = *s++;
}
return dest;
}
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