[PATCH] D155295: [InstCombine] Allow SimplifyDemandedVectorElts to look through freeze

[Jay Foad via Phabricator via llvm-commits]

foad added a comment.

> I think this is legal, but I believe we need to preserve the current results in shufflevector_freezepoison.ll -- it's a pattern we try to intentionally preserve to the backend.

I don't understand the bigger picture here. Why do we ever combine "freeze poison" into undef? In which cases do we not want to do that?


Repository:
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  https://reviews.llvm.org/D155295/new/

https://reviews.llvm.org/D155295