[PATCH] D67205: [SimplifyCFG] Don't SimplifyBranchOnICmpChain with ExtraCase

[Evgenii Stepanov via Phabricator via llvm-commits]

eugenis added a comment.

Basically, the only rule is that you should not speculatively introduce a conditional branch on value that might be undef and is not guaranteed to execute in the input IR.

You can find an investigation of a similar problem in LoopUnswitch in this bug:
https://bugs.llvm.org/show_bug.cgi?id=28054
It has some ideas of a better approach at the end, but we never acted on those. It sounds like a very hard problem.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D67205/new/

https://reviews.llvm.org/D67205