[all-commits] [llvm/llvm-project] fc2b4a: [DAGCombine] visitEXTRACT_VECTOR_ELT - add Simplif...

[Simon Pilgrim via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: fc2b4a02b1a82c40ac1459cd15b9911ebfc78acc
      https://github.com/llvm/llvm-project/commit/fc2b4a02b1a82c40ac1459cd15b9911ebfc78acc
  Author: Simon Pilgrim <llvm-dev at redking.me.uk>
  Date:   2020-02-20 (Thu, 20 Feb 2020)

  Changed paths:
    M llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
    M llvm/test/CodeGen/AArch64/vecreduce-and-legalization.ll
    M llvm/test/CodeGen/AMDGPU/extractelt-to-trunc.ll
    M llvm/test/CodeGen/AMDGPU/idot4s.ll
    M llvm/test/CodeGen/AMDGPU/idot4u.ll
    M llvm/test/CodeGen/AMDGPU/idot8s.ll
    M llvm/test/CodeGen/AMDGPU/store-weird-sizes.ll
    M llvm/test/CodeGen/X86/psadbw.ll
    M llvm/test/CodeGen/X86/vector-reduce-mul.ll

  Log Message:
  -----------
  [DAGCombine] visitEXTRACT_VECTOR_ELT - add SimplifyDemandedBits multi use support

Similar to what we already do with SimplifyDemandedVectorElts, call SimplifyDemandedBits across all the extracted elements of the source vector, treating it as single use.

There's a minor regression in store-weird-sizes.ll which will be addressed in an upcoming SimplifyDemandedBits patch.