[all-commits] [llvm/llvm-project] 97e921: [PatternMatch] create and use matcher for 'not' th...

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  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 97e921c81fbfa75d6863cf08268373983193d420
      https://github.com/llvm/llvm-project/commit/97e921c81fbfa75d6863cf08268373983193d420
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2021-12-02 (Thu, 02 Dec 2021)

  Changed paths:
    M llvm/include/llvm/IR/PatternMatch.h
    M llvm/lib/Analysis/InstructionSimplify.cpp
    M llvm/unittests/IR/PatternMatch.cpp

  Log Message:
  -----------
  [PatternMatch] create and use matcher for 'not' that excludes undef elements

We needed a stricter version of m_Not for D114462, but I wasn't
sure if that was going to be required anywhere else, so I didn't bother
to make that reusable.

It turns out we have one more existing simplification that needs
this (currently miscompiles):
https://alive2.llvm.org/ce/z/9-nTKi

And there's at least one more fold in that family that we could add.

Differential Revision: https://reviews.llvm.org/D114882