; REQUIRES: asserts
; XFAIL: *
; RUN: opt -passes='unswitch<nontrivial>' -disable-output -S < %s
; RUN: opt -simple-loop-unswitch -enable-nontrivial-unswitch -disable-output -S < %s

; This loop shouldn't trigger asserts in SimpleLoopUnswitch.
define void @test_redundant_switch(i1* %ptr, i32 %cond) {
entry:
  br label %loop_begin

loop_begin:
  switch i32 %cond, label %loop_body [
      i32 0, label %loop_body
  ]

loop_body:
  br label %loop_latch

loop_latch:
  %v = load i1, i1* %ptr
  br i1 %v, label %loop_begin, label %loop_exit

loop_exit:
  ret void
}

Add a test case exposing a bug
[SimpleLoopUnswitch] Add a test case exposing a bug

This test exposes a bug in SimpleLoopUnswitch that leads to a crash on
assert(SuccessorsCount > 1 && "Cannot unswitch a condition without multiple distinct successors!");
when SimpleLoopUnswitch considers unswitching of a loop by a switch with one successor.

Fix will be submitted soon.

Patch Author: Daniil Suchkov.

Reviewers: reames, asbirlea, skatkov
Reviewed By: skatkov
Subscribers: zzheng, llvm-commits
Differential Revision: https://reviews.llvm.org/D64403


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@365600 91177308-0d34-0410-b5e6-96231b3b80d8
