[all-commits] [llvm/llvm-project] 9d6d24: [JumpThreading][VectorUtils] avoid infinite loop o...

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  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 9d6d24c25056c17db56cf1ef5124f82eb18afc2c
      https://github.com/llvm/llvm-project/commit/9d6d24c25056c17db56cf1ef5124f82eb18afc2c
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2020-12-02 (Wed, 02 Dec 2020)

  Changed paths:
    M llvm/lib/Analysis/VectorUtils.cpp
    M llvm/test/Transforms/JumpThreading/unreachable-loops.ll

  Log Message:
  -----------
  [JumpThreading][VectorUtils] avoid infinite loop on unreachable IR

https://llvm.org/PR48362

It's possible that we could stub this out sooner somewhere
within JumpThreading, but I'm not sure how to do that, and
then we would still have potential danger in other callers.

I can't find a way to trigger this using 'instsimplify',
however, because that already has a bailout on unreachable
blocks.