[all-commits] [llvm/llvm-project] 5cce97: [DAG] isSplatValue - improve ISD::VECTOR_SHUFFLE s...

[Simon Pilgrim via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 5cce97d61e18e49033954793f4bc28906c75a305
      https://github.com/llvm/llvm-project/commit/5cce97d61e18e49033954793f4bc28906c75a305
  Author: Simon Pilgrim <llvm-dev at redking.me.uk>
  Date:   2022-03-02 (Wed, 02 Mar 2022)

  Changed paths:
    M llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
    M llvm/test/CodeGen/X86/vector-shift-ashr-256.ll

  Log Message:
  -----------
  [DAG] isSplatValue - improve ISD::VECTOR_SHUFFLE splat detection

Currently we only check for splat shuffles, this extends it to see if the source operand is a splat across the demanded elts based upon the shuffle mask