[all-commits] [llvm/llvm-project] 38a64a: [ControlHeightReduction] Don't combine a "poison" ...

[kazutakahirata via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 38a64aab4a3fbaaeb383638ff654247902796556
      https://github.com/llvm/llvm-project/commit/38a64aab4a3fbaaeb383638ff654247902796556
  Author: Kazu Hirata <kazu at google.com>
  Date:   2023-02-28 (Tue, 28 Feb 2023)

  Changed paths:
    M llvm/lib/Transforms/Instrumentation/ControlHeightReduction.cpp
    A llvm/test/Transforms/PGOProfile/chr-poison.ll

  Log Message:
  -----------
  [ControlHeightReduction] Don't combine a "poison" branch

Without this patch, the control height reduction pass would combine a
"poison" branch with an earlier well-defined branch, turning the
earlier branch into a "poison" branch also.

This patch fixes the problem by rejecting "poison" conditional
branches.

Differential Revision: https://reviews.llvm.org/D145008