fastest way to copy hunks of memory

[Dan Kogai]

In article <1990May2.200732.11851 at eci386.uucp> clewis at eci386.UUCP (Chris Lewis) writes:
>Perhaps 
>
>    while(size--)
>	*p1++ = *p2++;

or even

void *memcpy(void *to, void *from, size_t size){
	register int 	size_l = size / 4,	/* or (size >> log2(sizeof int)) */
					tail = size % 4;	/* or (size & log2(sizeof int)) */
	void			*result = to;				
	while(size_l--) (int *)to++ = (int *)from++;
	while(tail--) (char *)p1++ = (char *)p2++;
	return result;
}

	This shold work almost 4 times as fast compared to just inclementing
by bytes--it uses full length of register.  The problem is that it doesn't
work if either (void *to) and (void *from) is not aligned and the macine
architecure doesn't allow unaligned assignment.  Such functions as
memcpy() should be written in assembler, I think...

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