[all-commits] [llvm/llvm-project] bab44a: [InstCombine] matchOrConcat - match BITREVERSE

[Simon Pilgrim via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: bab44a698e821292ecce4ee01a61964a0a40c33e
      https://github.com/llvm/llvm-project/commit/bab44a698e821292ecce4ee01a61964a0a40c33e
  Author: Simon Pilgrim <llvm-dev at redking.me.uk>
  Date:   2020-05-10 (Sun, 10 May 2020)

  Changed paths:
    M llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
    M llvm/test/Transforms/InstCombine/or-concat.ll

  Log Message:
  -----------
  [InstCombine] matchOrConcat - match BITREVERSE

Fold or(zext(bitreverse(x)),shl(zext(bitreverse(y)),bw/2) -> bitreverse(or(zext(x),shl(zext(y),bw/2))

Practically this is the same as the BSWAP pattern so we might as well handle it.