[all-commits] [llvm/llvm-project] 40cd26: Loop peeling: check that latch is conditional branch

[Joseph Tremoulet via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 40cd262c4339c8cbd67bf5c96c4a052ae02a8660
      https://github.com/llvm/llvm-project/commit/40cd262c4339c8cbd67bf5c96c4a052ae02a8660
  Author: Joseph Tremoulet <jotrem at microsoft.com>
  Date:   2021-01-20 (Wed, 20 Jan 2021)

  Changed paths:
    M llvm/lib/Transforms/Utils/LoopPeel.cpp
    M llvm/test/Transforms/LoopUnroll/peel-loop-conditions.ll

  Log Message:
  -----------
  Loop peeling: check that latch is conditional branch

Loop peeling assumes that the loop's latch is a conditional branch.  Add
a check to canPeel that explicitly checks for this, and testcases that
otherwise fail an assertion when trying to peel a loop whose back-edge
is a switch case or the non-unwind edge of an invoke.

Reviewed By: skatkov, fhahn

Differential Revision: https://reviews.llvm.org/D94995