[all-commits] [llvm/llvm-project] d6467e: AMDGPU: Fix infinite loop in DAG combine with fneg...

[Matt Arsenault via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: d6467e00dfccf10aa91e5a1d55d981a9b13642a3
      https://github.com/llvm/llvm-project/commit/d6467e00dfccf10aa91e5a1d55d981a9b13642a3
  Author: Matt Arsenault <Matthew.Arsenault at amd.com>
  Date:   2021-06-18 (Fri, 18 Jun 2021)

  Changed paths:
    M llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
    M llvm/test/CodeGen/AMDGPU/fneg-combines.ll

  Log Message:
  -----------
  AMDGPU: Fix infinite loop in DAG combine with fneg + fma

We were not reporting isFNegFree for v2f32, although it is effectively
free after legalization. The generic combine was pulling fneg out of
the fma source operands, and the AMDGPU combine was doing the
opposite.