--- /dev/null	2017-01-22 10:16:57.869617664 -0800
+++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/cfg/LocationSet.java	2017-02-15 17:07:11.336063849 -0800
@@ -0,0 +1,141 @@
+/*
+ * Copyright (c) 2015, 2016, 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.compiler.nodes.cfg;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import org.graalvm.compiler.core.common.LocationIdentity;
+
+public class LocationSet {
+    private LocationIdentity firstLocation;
+    private List<LocationIdentity> list;
+
+    public LocationSet() {
+        list = null;
+    }
+
+    public LocationSet(LocationSet other) {
+        this.firstLocation = other.firstLocation;
+        if (other.list != null && other.list.size() > 0) {
+            list = new ArrayList<>(other.list);
+        }
+    }
+
+    private void initList() {
+        if (list == null) {
+            list = new ArrayList<>(4);
+        }
+    }
+
+    public boolean isEmpty() {
+        return firstLocation == null;
+    }
+
+    public boolean isAny() {
+        return firstLocation != null && firstLocation.isAny();
+    }
+
+    public void add(LocationIdentity location) {
+        if (this.isAny()) {
+            return;
+        } else if (location.isAny()) {
+            firstLocation = location;
+            list = null;
+        } else if (location.isImmutable()) {
+            return;
+        } else {
+            assert location.isMutable() && location.isSingle();
+            if (firstLocation == null) {
+                firstLocation = location;
+            } else if (location.equals(firstLocation)) {
+                return;
+            } else {
+                initList();
+                for (int i = 0; i < list.size(); ++i) {
+                    LocationIdentity value = list.get(i);
+                    if (location.equals(value)) {
+                        return;
+                    }
+                }
+                list.add(location);
+            }
+        }
+    }
+
+    public void addAll(LocationSet other) {
+        if (other.firstLocation != null) {
+            add(other.firstLocation);
+        }
+        List<LocationIdentity> otherList = other.list;
+        if (otherList != null) {
+            for (LocationIdentity l : otherList) {
+                add(l);
+            }
+        }
+    }
+
+    public boolean contains(LocationIdentity locationIdentity) {
+        assert locationIdentity.isSingle();
+        assert locationIdentity.isMutable();
+        if (LocationIdentity.any().equals(firstLocation)) {
+            return true;
+        }
+        if (locationIdentity.equals(firstLocation)) {
+            return true;
+        }
+        if (list != null) {
+            for (int i = 0; i < list.size(); ++i) {
+                LocationIdentity value = list.get(i);
+                if (locationIdentity.equals(value)) {
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
+    public List<LocationIdentity> getCopyAsList() {
+        ArrayList<LocationIdentity> result = new ArrayList<>();
+        if (firstLocation != null) {
+            result.add(firstLocation);
+        }
+        if (list != null) {
+            result.addAll(list);
+        }
+        return result;
+    }
+
+    @Override
+    public String toString() {
+        if (this.isAny()) {
+            return "ANY";
+        } else if (this.isEmpty()) {
+            return "EMPTY";
+        } else {
+            List<LocationIdentity> copyAsList = getCopyAsList();
+            return Arrays.toString(copyAsList.toArray(new LocationIdentity[0]));
+        }
+    }
+}