代码

void my_memset(char *a, char c, unsigned n) {
  unsigned i;
  unsigned half = n / 2;
  for(i = 0; i < half; i++) {
		a[i] = 'c';
    __builtin_prefetch(a + i + i);
  }
  for (; i < n; i++) a[i] = 'c';
}

评测结果