[PATCH] D48987: [InstCombine] drop poison flags for shuffle transforms with undefs

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri added a comment.

So my concerns weren't unfounded :/
Do we want to also do such kind of fixup in `VisitShl()` in instcombine, for every `shl` we visit?


https://reviews.llvm.org/D48987