[all-commits] [llvm/llvm-project] 122b06: [InstSimplify] Don't fold vectors of partial undef...

[topperc via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 122b0640fc97202bacb630744dfc6da58f11af42
      https://github.com/llvm/llvm-project/commit/122b0640fc97202bacb630744dfc6da58f11af42
  Author: Craig Topper <craig.topper at intel.com>
  Date:   2020-07-09 (Thu, 09 Jul 2020)

  Changed paths:
    M llvm/lib/Analysis/InstructionSimplify.cpp
    M llvm/test/Transforms/InstSimplify/select.ll

  Log Message:
  -----------
  [InstSimplify] Don't fold vectors of partial undef in SimplifySelectInst if the non-undef element value might produce poison

We can't fold to the non-undef value unless we know it isn't poison. So check each element with isGuaranteedNotToBeUndefOrPoison. This currently rules out all constant expressions.

Differential Revision: https://reviews.llvm.org/D83442