Update moveToVALU method to accept worklist of instructions.
Top/first element of worklist will be picked up to process.
Instruction will be moved to VALU or legalizeOperands is called on it before all the instruction prior to it in machine function are processed. legalizeOperands will be able to process the operands together with this change.
This patch is required to legalize rsrc and soffset of MBUF instruction together and create single waterfall loop. Prerequisite for D141030
It doesn't make sense to me to construct RPO to create a list like this. The whole iteration would just work in RPO