[all-commits] [llvm/llvm-project] 3ae61e: [InstCombine] Turn Add into Or even when undef (#1...

[Ken Matsui via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 3ae61eb220dc8f1fa0dd551a9575237b84dae61d
      https://github.com/llvm/llvm-project/commit/3ae61eb220dc8f1fa0dd551a9575237b84dae61d
  Author: Ken Matsui <26405363+ken-matsui at users.noreply.github.com>
  Date:   2026-07-06 (Mon, 06 Jul 2026)

  Changed paths:
    M llvm/include/llvm/Analysis/ValueTracking.h
    M llvm/lib/Analysis/ValueTracking.cpp
    M llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp
    M llvm/test/Transforms/InstCombine/add.ll
    M llvm/test/Transforms/InstCombine/masked-merge-add.ll
    M llvm/test/Transforms/InstCombine/pr53357.ll
    M llvm/unittests/Analysis/ValueTrackingTest.cpp

  Log Message:
  -----------
  [InstCombine] Turn Add into Or even when undef (#171556)

Since 03d4a9d94da30590ebfc444cf13a8763f47b7bb9, Add is turned into
DisjointOr, and since 5c3496ff33ce8e4cc6f8c18edd7ae5fc65d23fdf, Add
isn't turned into DisjointOr when undef. However, Add can still be
turned into Or even when undef.

This patch restores the transformation behavior we had in LLVM 17, while
continuing to generate DisjointOr when possible.

Alive2: https://alive2.llvm.org/ce/z/ZT0ZFj



To unsubscribe from these emails, change your notification settings at https://github.com/llvm/llvm-project/settings/notifications