c语言之自定义memcpy

void *Memcpy(void *dest, const void *src, size_t count)  
{  cout<<"sizeof(dest)是："<<sizeof(dest)<<endl;int bytelen=count/sizeof(dest);	/*按CPU位宽拷贝*/int slice=count%sizeof(dest);	/*剩余的按字节拷贝*/unsigned int* d = (unsigned int*)dest;  unsigned int* s = (unsigned int*)src;  if (((int)dest > ((int)src+count)) || (dest < src))  {  while (bytelen--)  *d++ = *s++;  while (slice--)  *(char *)d++ = *(char *)s++; }  else /* overlap重叠 */  {  d = (unsigned int*)((unsigned int)dest + count - 4); /*指针位置从末端开始，注意偏置 */  s = (unsigned int*)((unsigned int)src + count -4);  while (bytelen --)  *d-- = *s--;  d++;s++;char * d1=(char *)d;char * s1=(char *)s;d1--;s1--;while (slice --)  *(char *)d1-- = *(char *)s1--; }  return dest;  
}