diff -r 6659a8f57d78 -r 64e4b1686141 src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/java/UnsafeCompareAndExchangeNode.java
--- a/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/java/UnsafeCompareAndExchangeNode.java	Wed Jun 06 08:32:08 2018 -0700
+++ b/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/java/UnsafeCompareAndExchangeNode.java	Wed Jun 06 09:37:44 2018 -0700
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2011, 2018, 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
@@ -23,6 +23,7 @@
 package org.graalvm.compiler.nodes.java;
 
 import jdk.vm.ci.meta.JavaKind;
+import org.graalvm.compiler.core.common.type.Stamp;
 import org.graalvm.compiler.graph.NodeClass;
 import org.graalvm.compiler.nodeinfo.NodeInfo;
 import org.graalvm.compiler.nodes.NodeView;
@@ -55,8 +56,7 @@
     private final LocationIdentity locationIdentity;
 
     public UnsafeCompareAndExchangeNode(ValueNode object, ValueNode offset, ValueNode expected, ValueNode newValue, JavaKind valueKind, LocationIdentity locationIdentity) {
-        super(TYPE, expected.stamp(NodeView.DEFAULT).meet(newValue.stamp(NodeView.DEFAULT)));
-        assert expected.stamp(NodeView.DEFAULT).isCompatible(newValue.stamp(NodeView.DEFAULT));
+        super(TYPE, meetInputs(expected.stamp(NodeView.DEFAULT), newValue.stamp(NodeView.DEFAULT)));
         this.object = object;
         this.offset = offset;
         this.expected = expected;
@@ -65,6 +65,11 @@
         this.locationIdentity = locationIdentity;
     }
 
+    private static Stamp meetInputs(Stamp expected, Stamp newValue) {
+        assert expected.isCompatible(newValue);
+        return expected.unrestricted().meet(newValue.unrestricted());
+    }
+
     public ValueNode object() {
         return object;
     }