[PATCH] D86578: [TargetLowering] Combine known bits for icmp in SimplifySetCC (PR41182)

[Matt D'Arcangelo via Phabricator via llvm-commits]

darcangelo.matthew added a comment.
Herald added a subscriber: danielkiss.

@RKSimon Meant to say this before - Thank you for putting up additional reviewers Simon, I appreciate your help with this



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Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:14059
+      // unconditionally take the branch, remove all other successors of CurBB
+      auto SuccMBB = CurMBB->succ_begin();
+      while (SuccMBB != CurMBB->succ_end()) {
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craig.topper wrote:
> I'm not sure if we can really do this from SelectionDAG. Is there anywhere else that does this in tree?
> I'm not sure if we can really do this from SelectionDAG. Is there anywhere else that does this in tree?

I found the UnreachableMachineBlockElim pass which may be able to be enhanced for this, but I'm still looking


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Comment at: llvm/test/CodeGen/X86/test-shrink.ll:574
   ret void
 no:
   ret void
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craig.topper wrote:
> Can we pre-commit the IR changes here?
Thank you for taking a look at the changes. 

> Can we pre-commit the IR changes here?

Sorry, would you be able to elaborate what you mean here? Do you mean separate these out into another pre-commit review?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D86578/new/

https://reviews.llvm.org/D86578