I was expecting this to be a nfc but Silvermont seems to be setup a little differently:
A folded store needs a cycle on MEC_RSV for the store data, but it does not
need an extra port cycle to recompute the address.
def : WriteRes<WriteRMW, [SLM_MEC_RSV]>;
So moving from WriteStore to WriteRMW reduces predicted port pressure. From what I can tell this is correct but I wanted to confirm with some Intel guys as my knowledge of SLM is very weak.