From f62478a34a38b129041f43766bbf5525c4914e18 Mon Sep 17 00:00:00 2001
From: David Majnemer <david.majnemer@gmail.com>
Date: Sat, 23 Jan 2016 06:00:44 +0000
Subject: [PATCH] [PruneEH] Don't try to insert a terminator after another
 terminator

LLVM's BasicBlock has a single terminator, it is not valid to have two.

llvm-svn: 258616
---
 lib/Transforms/IPO/PruneEH.cpp     |  3 ++-
 test/Transforms/PruneEH/pr26263.ll | 26 ++++++++++++++++++++++++++
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/lib/Transforms/IPO/PruneEH.cpp b/lib/Transforms/IPO/PruneEH.cpp
index c2f55d896ba..22a95fa03f7 100644
--- a/lib/Transforms/IPO/PruneEH.cpp
+++ b/lib/Transforms/IPO/PruneEH.cpp
@@ -252,7 +252,8 @@ void PruneEH::DeleteBasicBlock(BasicBlock *BB) {
   }
 
   if (TokenInst) {
-    changeToUnreachable(TokenInst->getNextNode(), /*UseLLVMTrap=*/false);
+    if (!isa<TerminatorInst>(TokenInst))
+      changeToUnreachable(TokenInst->getNextNode(), /*UseLLVMTrap=*/false);
   } else {
     // Get the list of successors of this block.
     std::vector<BasicBlock *> Succs(succ_begin(BB), succ_end(BB));
diff --git a/test/Transforms/PruneEH/pr26263.ll b/test/Transforms/PruneEH/pr26263.ll
index 3670f00d811..17fafeb6850 100644
--- a/test/Transforms/PruneEH/pr26263.ll
+++ b/test/Transforms/PruneEH/pr26263.ll
@@ -27,4 +27,30 @@ cleanupret:
 
 ; CHECK: cleanupret from %[[cp]] unwind to caller
 
+define void @test2() personality i32 (...)* @__CxxFrameHandler3 {
+  invoke void @neverthrows()
+          to label %try.cont unwind label %catchswitch
+
+try.cont:
+  ret void
+
+catchswitch:
+  %cs = catchswitch within none [label %catchpad] unwind to caller
+
+catchpad:
+  %cp = catchpad within %cs []
+  unreachable
+
+ret:
+  ret void
+}
+
+; CHECK-LABEL: define void @test2(
+; CHECK: call void @neverthrows()
+
+; CHECK: %[[cs:.*]] = catchswitch within none [label
+
+; CHECK: catchpad within %[[cs]] []
+; CHECK-NEXT: unreachable
+
 declare i32 @__CxxFrameHandler3(...)