diff --git a/llvm/include/llvm/Transforms/Scalar/LoopPassManager.h b/llvm/include/llvm/Transforms/Scalar/LoopPassManager.h
--- a/llvm/include/llvm/Transforms/Scalar/LoopPassManager.h
+++ b/llvm/include/llvm/Transforms/Scalar/LoopPassManager.h
@@ -356,6 +356,15 @@
     Worklist.insert(CurrentL);
   }
 
+  void markLoopNestChanged() {
+    SkipCurrentLoop = true;
+
+    Loop *L = CurrentL;
+    while (auto *PL = L->getParentLoop())
+      L = PL;
+    Worklist.insert(L);
+  }
+
 private:
   friend class llvm::FunctionToLoopPassAdaptor;
 
diff --git a/llvm/lib/Transforms/Scalar/LoopInterchange.cpp b/llvm/lib/Transforms/Scalar/LoopInterchange.cpp
--- a/llvm/lib/Transforms/Scalar/LoopInterchange.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopInterchange.cpp
@@ -44,6 +44,7 @@
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Transforms/Scalar.h"
+#include "llvm/Transforms/Scalar/LoopPassManager.h"
 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
 #include "llvm/Transforms/Utils/LoopUtils.h"
 #include <cassert>
@@ -1766,5 +1767,6 @@
   OptimizationRemarkEmitter ORE(&F);
   if (!LoopInterchange(&AR.SE, &AR.LI, &DI, &AR.DT, CC, &ORE).run(LN))
     return PreservedAnalyses::all();
+  U.markLoopNestChanged();
   return getLoopPassPreservedAnalyses();
 }
diff --git a/llvm/lib/Transforms/Scalar/LoopPassManager.cpp b/llvm/lib/Transforms/Scalar/LoopPassManager.cpp
--- a/llvm/lib/Transforms/Scalar/LoopPassManager.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopPassManager.cpp
@@ -104,6 +104,8 @@
       break;
     }
 
+    assert(L.isOutermost());
+
     // Update the analysis manager as each pass runs and potentially
     // invalidates analyses.
     AM.invalidate(L, *PassPA);