I know at least MSVC's memcpy on x86_64 still results in a rep movsb if the cpuid flag that says rep movsb is fast is set, which it should be on all x86 chips f

I know at least MSVC's memcpy on x86_64 still results in a rep movsb if the cpuid flag that says rep movsb is fast is set, which it should be on all x86 chips from about 2011/2012 and onward ;)