[all-commits] [llvm/llvm-project] 5126c3: [CGP] Freeze condition when despeculating ctlz/cttz

[Nikita Popov via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 5126c38012c1d00729549ff4e4cb9d2be66ab9ab
      https://github.com/llvm/llvm-project/commit/5126c38012c1d00729549ff4e4cb9d2be66ab9ab
  Author: Nikita Popov <npopov at redhat.com>
  Date:   2022-05-23 (Mon, 23 May 2022)

  Changed paths:
    M llvm/lib/CodeGen/CodeGenPrepare.cpp
    M llvm/test/Transforms/CodeGenPrepare/X86/cttz-ctlz.ll

  Log Message:
  -----------
  [CGP] Freeze condition when despeculating ctlz/cttz

Freeze the condition of the newly introduced conditional branch,
to avoid immediate undefined behavior if the input to ctlz/cttz
was originally poison.

Differential Revision: https://reviews.llvm.org/D125887