[PATCH] D36880: [GSel]: Add a cleanup combiner to cleanup legalization artifacts

[Aditya Nandakumar via Phabricator via llvm-commits]

aditya_nandakumar added inline comments.


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Comment at: lib/CodeGen/GlobalISel/Legalizer.cpp:170
+      SmallVector<MachineInstr *, 4> DeadInsts;
+      Changed |= C.tryCombineMerges(*MI, DeadInsts);
+      for (auto *DeadMI : DeadInsts)
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volkan wrote:
> Do we still need this code block? I think the `tryCombineInstruction` call above already handles this case.
Yes - the tryCombine is currently only called on newly created instructions (legalization artifacts) where as we want to try to combine already existing merges.


https://reviews.llvm.org/D36880