[SimplifyCFG] Don't DCE catchret because the successor is unreachable

CatchReturnInst has side-effects: it runs a destructor.  This destructor
could conceivably run forever/call exit/etc. and should not be removed.

llvm-svn: 251461

1 files changed, 20 insertions, 0 deletions

diff --git a/llvm/test/Transforms/SimplifyCFG/wineh-unreachable.ll b/llvm/test/Transforms/SimplifyCFG/wineh-unreachable.ll
index 7db883b2412..31d567f6492 100644
--- a/llvm/test/Transforms/SimplifyCFG/wineh-unreachable.ll
+++ b/llvm/test/Transforms/SimplifyCFG/wineh-unreachable.ll
@@ -86,3 +86,23 @@ unreachable.unwind:
   cleanuppad []
   unreachable
 }
+
+; CHECK-LABEL: define void @test5()
+define void @test5() personality i8* bitcast (void ()* @Personality to i8*) {
+entry:
+  invoke void @f()
+          to label %exit unwind label %catch.pad
+
+catch.pad:
+  %catch = catchpad []
+          to label %catch.body unwind label %catch.end
+
+catch.body:
+  catchret %catch to label %exit
+
+catch.end:
+  catchendpad unwind to caller
+
+exit:
+  unreachable
+}