src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.replacements/src/org/graalvm/compiler/replacements/nodes/BasicArrayCopyNode.java

rev 56282 : [mq]: graal

@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 2013, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2013, 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
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.

@@ -142,11 +142,12 @@
     public void lower(LoweringTool tool) {
         tool.getLowerer().lower(this, tool);
     }
 
     private static boolean checkBounds(int position, int length, VirtualObjectNode virtualObject) {
-        return position >= 0 && position + length <= virtualObject.entryCount();
+        assert length >= 0;
+        return position >= 0 && position <= virtualObject.entryCount() - length;
     }
 
     private static boolean checkEntryTypes(int srcPos, int length, VirtualObjectNode src, ResolvedJavaType destComponentType, VirtualizerTool tool) {
         if (destComponentType.getJavaKind() == JavaKind.Object && !destComponentType.isJavaLangObject()) {
             for (int i = 0; i < length; i++) {