--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.jvmci.options/src/com/oracle/jvmci/options/StableOptionValue.java	Tue May 26 23:21:15 2015 +0200
@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2013, 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.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package com.oracle.jvmci.options;
+
+/**
+ * An option that always returns the same {@linkplain #getValue() value}.
+ */
+public class StableOptionValue<T> extends OptionValue<T> {
+
+    /**
+     * Creates a stable option value.
+     */
+    public StableOptionValue(T value) {
+        super(value);
+    }
+
+    /**
+     * Used to assert the invariant for stability. Without using locks, this check is not safe
+     * against races and so it's only an assertion.
+     */
+    private boolean getValueCalled;
+
+    /**
+     * Creates an uninitialized stable option value for a subclass that initializes itself
+     * {@link #initialValue() lazily}.
+     */
+    public StableOptionValue() {
+    }
+
+    /**
+     * Gets the value of this option.
+     */
+    @Override
+    public final T getValue() {
+        T result = super.getValue();
+        assert initGetValueCalled();
+        return result;
+    }
+
+    private boolean initGetValueCalled() {
+        getValueCalled = true;
+        return true;
+    }
+
+    /**
+     * {@inheritDoc}
+     * <p>
+     * This must only be called if {@link #getValue()} has never been called.
+     */
+    @Override
+    public final void setValue(Object v) {
+        assert !getValueCalled;
+        super.setValue(v);
+    }
+}