[all-commits] [llvm/llvm-project] 7f6986: [LoopUnroll] Fix a crash

[serguei-katkov via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 7f69860243e8933c3da1177afde0d3cb6544d04e
      https://github.com/llvm/llvm-project/commit/7f69860243e8933c3da1177afde0d3cb6544d04e
  Author: Serguei Katkov <serguei.katkov at azul.com>
  Date:   2021-01-11 (Mon, 11 Jan 2021)

  Changed paths:
    M llvm/lib/Transforms/Utils/LoopUnroll.cpp
    A llvm/test/Transforms/LoopUnroll/unroll-after-peel.ll

  Log Message:
  -----------
  [LoopUnroll] Fix a crash

Loop peeling as a last step triggers loop simplification and this
can change the loop structure. As a result all cashed values like
latch branch becomes invalid.

Patch re-structure the code to take into account the possible
changes caused by peeling.

Reviewers: dmgreen, Meinersbur, etiotto, fhahn, efriedma, bmahjour
Reviewed By: Meinersbur, fhahn
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D93686