[all-commits] [llvm/llvm-project] 9a4321: [LoopInterchange] Adjust assertions when updating ...

[Florian Hahn via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 9a432161c68774e6c717616e3d688142e89bbb42
      https://github.com/llvm/llvm-project/commit/9a432161c68774e6c717616e3d688142e89bbb42
  Author: Florian Hahn <flo at fhahn.com>
  Date:   2019-11-24 (Sun, 24 Nov 2019)

  Changed paths:
    M llvm/lib/Transforms/Scalar/LoopInterchange.cpp
    A llvm/test/Transforms/LoopInterchange/update-condbranch-duplicate-successors.ll

  Log Message:
  -----------
  [LoopInterchange] Adjust assertions when updating successors.

Currently the assertion in updateSuccessor is overly strict in some
cases and overly relaxed in other cases. For branches to the inner and
outer loop preheader it is too strict, because they can either be
unconditional branches or conditional branches with duplicate targets.
Both cases are fine and we can allow updating multiple successors.

On the other hand, we have to at least update one successor. This patch
adds such an assertion.