[all-commits] [llvm/llvm-project] 8f29e4: [X86][SSE] combineX86ShufflesRecursively - don't b...

[Simon Pilgrim via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 8f29e4407cc609764eeb450dc432297952ec6f49
      https://github.com/llvm/llvm-project/commit/8f29e4407cc609764eeb450dc432297952ec6f49
  Author: Simon Pilgrim <llvm-dev at redking.me.uk>
  Date:   2019-11-03 (Sun, 03 Nov 2019)

  Changed paths:
    M llvm/lib/Target/X86/X86ISelLowering.cpp

  Log Message:
  -----------
  [X86][SSE] combineX86ShufflesRecursively - don't bother merging shuffles with empty roots. NFCI.

This doesn't affect actual codegen, but is a minor refactor toward fixing PR43024 where we need to avoid excess changes (folding zeroables etc.) to the shuffle mask at Depth == 0.