Just like the `REP STOS` instruction, this removes a fairly nasty bit of
code generation from our dispatcher. This instruction behaves like a
memcpy/memmove when not dealing with the faulting behaviour around the
instruction.
With a microbench things improves this instruction's throughput by 3.5%
to 25.5% depending on operating size.
There is a TODO for implementing this instruction with ARM's future MOPS
instructions which will accelerate this implementation further.
Ryan Houdek
79170a23e5