[all-commits] [llvm/llvm-project] d9ffd3: [X86] combineCMP - attempt to simplify KSHIFTR mas...

[Simon Pilgrim via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: d9ffd3219e3817c1818b14eb1c3d5e274d9e3df7
      https://github.com/llvm/llvm-project/commit/d9ffd3219e3817c1818b14eb1c3d5e274d9e3df7
  Author: Simon Pilgrim <llvm-dev at redking.me.uk>
  Date:   2023-09-02 (Sat, 02 Sep 2023)

  Changed paths:
    M llvm/lib/Target/X86/X86ISelLowering.cpp
    M llvm/test/CodeGen/X86/avx512-insert-extract.ll
    M llvm/test/CodeGen/X86/movmsk-cmp.ll
    M llvm/test/CodeGen/X86/pr33349.ll
    M llvm/test/CodeGen/X86/pr34177.ll

  Log Message:
  -----------
  [X86] combineCMP - attempt to simplify KSHIFTR mask element extractions when just comparing against zero (REAPPLIED)

We can just bitcast the pre-shifted mask as an integer and use TEST/BT directly.

Reapplied with fix for 239ab16ec121 which didn't set the comparison type correctly