[PATCH] D54839: [CodeGen] Enhance machine PHIs optimization

Mon Dec 10 02:36:36 PST 2018

anton-afanasyev added a comment.

Hi @MatzeB, as for special pass for COPYs propagation, I haven't found natural place for it after MIR ISel and before OptimizationPHIs among existing passes:

  X86 DAG->DAG Instruction Selection
  MachineDominator Tree Construction
  Local Dynamic TLS Access Clean-up
  X86 PIC Global Base Reg Initialization
  Expand ISel Pseudo-instructions
  X86 Domain Reassignment Pass
  Early Tail Duplication
  Optimize machine instruction PHIs

I think such pass could be useful right before OptimizePHIs, possibly making special passes in OptimizePHIs and MachineCSE needless.
But it is not related straightforwardly to this patch since COPYs check has been already in place before patch.

Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D54839/new/

https://reviews.llvm.org/D54839