How can I use SIMD to accelerate XOR two blocks of memory?

Question

I want to XOR two blocks of memory as quickly as possible, How can I use SIMD to accelerate it?

My original code is below:

void region_xor_w64(   uns         


        

Answer 1

Okay, if intels prefer going forward and prefer pointer ops over indexes, then:

void region_xor_w64(unsigned char *r1, unsigned char *r2, unsigned int i)
{
    while (i--)
        *r2++ ^= *r1++;
}

Mike