Index: lib/Transforms/Scalar/LoopUnswitch.cpp
===================================================================
--- lib/Transforms/Scalar/LoopUnswitch.cpp
+++ lib/Transforms/Scalar/LoopUnswitch.cpp
@@ -942,9 +942,9 @@
   if (DT) {
     // First, add both successors.
     SmallVector<DominatorTree::UpdateType, 3> Updates;
-    if (TrueDest != OldBranchParent)
+    if (TrueDest != OldBranchSucc)
       Updates.push_back({DominatorTree::Insert, OldBranchParent, TrueDest});
-    if (FalseDest != OldBranchParent)
+    if (FalseDest != OldBranchSucc)
       Updates.push_back({DominatorTree::Insert, OldBranchParent, FalseDest});
     // If both of the new successors are different from the old one, inform the
     // DT that the edge was deleted.