[all-commits] [llvm/llvm-project] df5ea2: [X86] Add shuffles showing failure to use PERMUTE(...

[Simon Pilgrim via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: df5ea2b12d482986269b74f7c9d2ccb8c5c90676
      https://github.com/llvm/llvm-project/commit/df5ea2b12d482986269b74f7c9d2ccb8c5c90676
  Author: Simon Pilgrim <llvm-dev at redking.me.uk>
  Date:   2022-05-15 (Sun, 15 May 2022)

  Changed paths:
    M llvm/test/CodeGen/X86/vector-shuffle-256-v4.ll

  Log Message:
  -----------
  [X86] Add shuffles showing failure to use PERMUTE(BLEND(X,Y))

One AVX2+ targets we have a immediate VPERMQ/PD cross-lane permute thats better than relying on a pair of VPERM2F128 cross-lanes to feed a blend.

Reported on discourse