diff -r 22baf8054a40 -r 08db5aa02f7b src/hotspot/share/oops/instanceKlass.cpp
--- a/src/hotspot/share/oops/instanceKlass.cpp	Sat Jan 05 10:48:54 2019 +0800
+++ b/src/hotspot/share/oops/instanceKlass.cpp	Sat Jan 05 20:08:24 2019 +0100
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -1199,14 +1199,6 @@
   }
 }
 
-bool InstanceKlass::compute_is_subtype_of(Klass* k) {
-  if (k->is_interface()) {
-    return implements_interface(k);
-  } else {
-    return Klass::compute_is_subtype_of(k);
-  }
-}
-
 bool InstanceKlass::implements_interface(Klass* k) const {
   if (this == k) return true;
   assert(k->is_interface(), "should be an interface class");