--- a/src/hotspot/share/opto/loopopts.cpp	Mon Aug 19 18:12:09 2019 -0700
+++ b/src/hotspot/share/opto/loopopts.cpp	Tue Aug 20 07:47:13 2019 +0200
@@ -324,7 +324,7 @@
       }
       return NULL;
     }
-    assert(m->is_Phi() || is_dominator(get_ctrl(m), n_ctrl), "m has strange control");
+    assert(n->is_Phi() || m->is_Phi() || is_dominator(get_ctrl(m), n_ctrl), "m has strange control");
   }
 
   return n_ctrl;