[all-commits] [llvm/llvm-project] bf4490: [InstCombine] add tests for difference-of-squares; ...

[Sanjay Patel via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: bf44905183efe54599956e308a236635c9b46e71
      https://github.com/llvm/llvm-project/commit/bf44905183efe54599956e308a236635c9b46e71
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2023-01-17 (Tue, 17 Jan 2023)

  Changed paths:
    M llvm/test/Transforms/InstCombine/sub.ll

  Log Message:
  -----------
  [InstCombine] add tests for difference-of-squares; NFC


  Commit: 68c197f07eeae71b9b772c9e0c3b846c7025b332
      https://github.com/llvm/llvm-project/commit/68c197f07eeae71b9b772c9e0c3b846c7025b332
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2023-01-17 (Tue, 17 Jan 2023)

  Changed paths:
    M llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp
    M llvm/test/Transforms/InstCombine/sub.ll

  Log Message:
  -----------
  [InstCombine] factor difference-of-squares to reduce multiplication

(X * X) - (Y * Y) --> (X + Y) * (X - Y)
https://alive2.llvm.org/ce/z/BAuRCf

The no-wrap propagation could be relaxed in some cases,
but there does not seem to be an obvious rule for that.


Compare: https://github.com/llvm/llvm-project/compare/0b38636f77df...68c197f07eea