--- a/src/jdk.internal.vm.compiler/share/classes/org.graalvm.util/src/org/graalvm/util/Equivalence.java	Fri Feb 02 10:37:48 2018 -0500
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,93 +0,0 @@
-/*
- * Copyright (c) 2017, 2017, 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 org.graalvm.util;
-
-/**
- * Strategy for comparing two objects. Default predefined strategies are {@link #DEFAULT},
- * {@link #IDENTITY}, and {@link #IDENTITY_WITH_SYSTEM_HASHCODE}.
- */
-public abstract class Equivalence {
-
-    /**
-     * Default equivalence calling {@link #equals(Object)} to check equality and {@link #hashCode()}
-     * for obtaining hash values. Do not change the logic of this class as it may be inlined in
-     * other places.
-     */
-    public static final Equivalence DEFAULT = new Equivalence() {
-
-        @Override
-        public boolean equals(Object a, Object b) {
-            return a.equals(b);
-        }
-
-        @Override
-        public int hashCode(Object o) {
-            return o.hashCode();
-        }
-    };
-
-    /**
-     * Identity equivalence using {@code ==} to check equality and {@link #hashCode()} for obtaining
-     * hash values. Do not change the logic of this class as it may be inlined in other places.
-     */
-    public static final Equivalence IDENTITY = new Equivalence() {
-
-        @Override
-        public boolean equals(Object a, Object b) {
-            return a == b;
-        }
-
-        @Override
-        public int hashCode(Object o) {
-            return o.hashCode();
-        }
-    };
-
-    /**
-     * Identity equivalence using {@code ==} to check equality and
-     * {@link System#identityHashCode(Object)} for obtaining hash values. Do not change the logic of
-     * this class as it may be inlined in other places.
-     */
-    public static final Equivalence IDENTITY_WITH_SYSTEM_HASHCODE = new Equivalence() {
-
-        @Override
-        public boolean equals(Object a, Object b) {
-            return a == b;
-        }
-
-        @Override
-        public int hashCode(Object o) {
-            return System.identityHashCode(o);
-        }
-    };
-
-    /**
-     * Subclass for creating custom equivalence definitions.
-     */
-    protected Equivalence() {
-    }
-
-    public abstract boolean equals(Object a, Object b);
-
-    public abstract int hashCode(Object o);
-}