[all-commits] [llvm/llvm-project] 518ec3: [InstCombine] add signbit check for or'd operands; ...

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  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 518ec39de7935f984fba13cbf5973774f4f05ea8
      https://github.com/llvm/llvm-project/commit/518ec39de7935f984fba13cbf5973774f4f05ea8
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2021-10-11 (Mon, 11 Oct 2021)

  Changed paths:
    M llvm/test/Transforms/InstCombine/icmp-or.ll

  Log Message:
  -----------
  [InstCombine] add signbit check for or'd operands; NFC


  Commit: 59441c73296e7c489ac1d71ffda2de3060bdd4f8
      https://github.com/llvm/llvm-project/commit/59441c73296e7c489ac1d71ffda2de3060bdd4f8
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2021-10-11 (Mon, 11 Oct 2021)

  Changed paths:
    M llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
    M llvm/test/Transforms/InstCombine/icmp-or.ll
    M llvm/test/Transforms/InstCombine/or.ll

  Log Message:
  -----------
  [InstCombine] fold signbit check of X | (X -1)

There may be some other patterns like this or a generalization,
but this is an example that I noticed would definitely regress
with a planned follow-up to D111410.

https://alive2.llvm.org/ce/z/GVpQDb


Compare: https://github.com/llvm/llvm-project/compare/fbddf22ef72d...59441c73296e