Add promotion and expansion of integer operands for experimental_vp_strided SelectionDAG nodes; the expansion is actually just a truncation of the stride operand.
Use GetExpandedInteger and assign NewOps[OpNo] to Lo
Looks good to me but I'd defer to @craig.topper in case I've missed something.
Would this be at all nicer if it was a single assert? assert((opc == load && opno == 3) || (opno == store && opno == 4))? Having explicit if/else just filled with asserts is a little odd to me.