[all-commits] [llvm/llvm-project] 664e1d: [LoopLoadElim] Make sure all loops are in simplify...

[max-azul via All-commits]

  Branch: refs/heads/temp-test-main
  Home:   https://github.com/llvm/llvm-project
  Commit: 664e1da485d244325947d056a271c3c733ad4c7c
      https://github.com/llvm/llvm-project/commit/664e1da485d244325947d056a271c3c733ad4c7c
  Author: Max Kazantsev <mkazantsev at azul.com>
  Date:   2020-11-26 (Thu, 26 Nov 2020)

  Changed paths:
    M llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp
    M llvm/test/Transforms/LoopLoadElim/pr-48150.ll

  Log Message:
  -----------
  [LoopLoadElim] Make sure all loops are in simplify form. PR48150

LoopLoadElim may end up expanding an AddRec from a loop
which is not the current loop. This loop may not be in simplify
form. We figure it out after the no-return point, so cannot bail
in this case.

AddRec requires simplify form to expand. The only way to ensure
this does not crash is to simplify all loops beforehand.

The issue only exists in new PM. Old PM requests LoopSimplify
required pass and it simplifies all loops before the opt begins.

Differential Revision: https://reviews.llvm.org/D91525
Reviewed By: asbirlea, aeubanks