Index: lib/Transforms/Utils/BasicBlockUtils.cpp
===================================================================
--- lib/Transforms/Utils/BasicBlockUtils.cpp
+++ lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -340,7 +340,15 @@
       InnermostPredLoop->addBasicBlockToLoop(NewBB, *LI);
   } else {
     L->addBasicBlockToLoop(NewBB, *LI);
-    if (SplitMakesNewLoopHeader)
+    // At this point, we know that some of the `preds` of OldBB are from within
+    // the loop L (since IsLoopEntry is false) and there's atleast one pred from
+    // outside the loop (SplitMakesNewLoopHeader is true). This does not mean
+    // that OldBB is the header of L by default (it could be an exit block of L
+    // where L is a subloop that does not satisfy loop-simplify form). We need
+    // to check OldBB is the header before changing the header to be the block
+    // split from OldBB (i.e. NewBB).
+    // FIXME: Should the header check be an assert?
+    if (SplitMakesNewLoopHeader && L->getHeader() == OldBB)
       L->moveToHeader(NewBB);
   }
 }
Index: test/Transforms/IRCE/correct-loop-info.ll
===================================================================
--- /dev/null
+++ test/Transforms/IRCE/correct-loop-info.ll
@@ -0,0 +1,65 @@
+; RUN: opt -irce < %s 
+
+; REQUIRES: asserts
+
+; IRCE creates the pre and post loop, and invokes the
+; SplitLandingPadPredecessor. Make sure that the update to the loopinfo does not
+; incorrectly move the split block as a header (since the block it was split from
+; was not the loop header).
+source_filename = "correct-loop-info.ll"
+
+define void @baz() personality i32* ()* @ham {
+bb:
+  br label %outerheader
+
+outerheader:                                              ; preds = %bb14, %bb
+  %tmp = icmp slt i32 undef, 84
+  br i1 %tmp, label %bb2, label %bb16
+
+bb2:                                              ; preds = %outerheader
+  br label %innerheader
+
+innerheader:                                              ; preds = %bb8, %bb2
+  %tmp4 = phi i32 [ %tmp6, %bb8 ], [ undef, %bb2 ]
+  invoke void @pluto() 
+          to label %bb5 unwind label %outer_exiting
+
+bb5:                                              ; preds = %innerheader
+  %tmp6 = add i32 %tmp4, 1
+  %tmp7 = icmp ult i32 %tmp6, 0
+  br i1 %tmp7, label %bb8, label %exit3
+
+bb8:                                              ; preds = %bb5
+  %tmp9 = icmp slt i32 %tmp6, 84
+  br i1 %tmp9, label %innerheader, label %bb13
+
+outer_exiting:                                             ; preds = %innerheader
+  %tmp11 = landingpad { i8*, i32 }
+          cleanup
+  switch i32 undef, label %exit2 [
+    i32 142, label %bb14
+    i32 448, label %exit
+  ]
+
+exit3:                                             ; preds = %bb5
+  ret void
+
+bb13:                                             ; preds = %bb8
+  unreachable
+
+bb14:                                             ; preds = %outer_exiting
+  br label %outerheader
+
+exit:                                             ; preds = %outer_exiting
+  ret void
+
+bb16:                                             ; preds = %outerheader
+  ret void
+
+exit2:                                             ; preds = %outer_exiting
+  ret void
+}
+
+declare i32* @ham()
+
+declare void @pluto()