diff --git a/llvm/lib/Transforms/Scalar/BreakCriticalEdges.cpp b/llvm/lib/Transforms/Scalar/BreakCriticalEdges.cpp
index b73ed55b8c9935b7a884bd79e6e51e8b4307b866..0c4974db10ac4c325d94ceb981ace69ec4e5d53a 100644
--- a/llvm/lib/Transforms/Scalar/BreakCriticalEdges.cpp
+++ b/llvm/lib/Transforms/Scalar/BreakCriticalEdges.cpp
@@ -118,7 +118,8 @@ void SplitCriticalEdge(TerminatorInst *TI, unsigned SuccNum, Pass *P) {
     // The new block is not the immediate dominator for any other nodes, but
     // TINode is the immediate dominator for the new node.
     //
-    DT->createNewNode(NewBB, TINode);
+    if (TINode)        // Don't break unreachable code!
+      DT->createNewNode(NewBB, TINode);
   }
 }
 
diff --git a/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp b/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp
index b73ed55b8c9935b7a884bd79e6e51e8b4307b866..0c4974db10ac4c325d94ceb981ace69ec4e5d53a 100644
--- a/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp
+++ b/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp
@@ -118,7 +118,8 @@ void SplitCriticalEdge(TerminatorInst *TI, unsigned SuccNum, Pass *P) {
     // The new block is not the immediate dominator for any other nodes, but
     // TINode is the immediate dominator for the new node.
     //
-    DT->createNewNode(NewBB, TINode);
+    if (TINode)        // Don't break unreachable code!
+      DT->createNewNode(NewBB, TINode);
   }
 }