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#include "memcpy.h"
#include <stdlib.h>
#include <stdint.h>
void fill(int *arr, size_t n)
{
for (int i = 0; i < n; i++) {
arr[i] = i << 4;
}
}
//#pragma GCC optimize ("unroll-loops")
#define UNROLL 8
void fast_memcpy(void *dst, void *src, size_t len)
{
uintptr_t ptr_mask = (uintptr_t) dst | (uintptr_t) src | len;
if ((ptr_mask & (sizeof(uintptr_t) - 1)) == 0) {
uintptr_t *d = dst, *s = src;
size_t n = len / sizeof(uintptr_t);
size_t lenu = ((n / UNROLL) * UNROLL) * sizeof(uintptr_t);
while (d < (uintptr_t *)(dst + lenu)) {
//for (int i = 0; i < UNROLL; i++)
// d[i] = s[i];
d[0] = s[0];
d[1] = s[1];
d[2] = s[2];
d[3] = s[3];
d[4] = s[4];
d[5] = s[5];
d[6] = s[6];
d[7] = s[7];
d += UNROLL;
s += UNROLL;
}
while (d < (uintptr_t *)(dst + len))
*(d++) = *(s++);
} else {
char *d = dst, *s = src;
while (d < (char *)(dst + len))
*(d++) = *(s++);
}
}
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