--- /dev/null	2017-01-22 10:16:57.869617664 -0800
+++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.graph/src/org/graalvm/compiler/graph/NodeBitMap.java	2017-02-15 16:58:35.787585988 -0800
@@ -0,0 +1,258 @@
+/*
+ * Copyright (c) 2011, 2011, 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.graph;
+
+import java.util.Arrays;
+import java.util.Iterator;
+
+import org.graalvm.compiler.graph.iterators.NodeIterable;
+
+public final class NodeBitMap implements NodeIterable<Node> {
+    private static final int SHIFT = 6;
+
+    private long[] bits;
+    private int nodeCount;
+    private int counter;
+    private final Graph graph;
+
+    public NodeBitMap(Graph graph) {
+        this.nodeCount = graph.nodeIdCount();
+        this.bits = new long[sizeForNodeCount(nodeCount)];
+        this.graph = graph;
+    }
+
+    private static int sizeForNodeCount(int nodeCount) {
+        return (nodeCount + Long.SIZE - 1) >> SHIFT;
+    }
+
+    public int getCounter() {
+        return counter;
+    }
+
+    private NodeBitMap(NodeBitMap other) {
+        this.bits = other.bits.clone();
+        this.nodeCount = other.nodeCount;
+        this.graph = other.graph;
+    }
+
+    public Graph graph() {
+        return graph;
+    }
+
+    public boolean isNew(Node node) {
+        return node.id() >= nodeCount;
+    }
+
+    public boolean isMarked(Node node) {
+        assert check(node, false);
+        return isMarked(node.id());
+    }
+
+    public boolean checkAndMarkInc(Node node) {
+        if (!isMarked(node)) {
+            this.counter++;
+            this.mark(node);
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    public boolean isMarked(int id) {
+        return (bits[id >> SHIFT] & (1L << id)) != 0;
+    }
+
+    public boolean isMarkedAndGrow(Node node) {
+        assert check(node, true);
+        int id = node.id();
+        checkGrow(id);
+        return isMarked(id);
+    }
+
+    public void mark(Node node) {
+        assert check(node, false);
+        int id = node.id();
+        bits[id >> SHIFT] |= (1L << id);
+    }
+
+    public void markAndGrow(Node node) {
+        assert check(node, true);
+        int id = node.id();
+        checkGrow(id);
+        bits[id >> SHIFT] |= (1L << id);
+    }
+
+    public void clear(Node node) {
+        assert check(node, false);
+        int id = node.id();
+        bits[id >> SHIFT] &= ~(1L << id);
+    }
+
+    public void clearAndGrow(Node node) {
+        assert check(node, true);
+        int id = node.id();
+        checkGrow(id);
+        bits[id >> SHIFT] &= ~(1L << id);
+    }
+
+    private void checkGrow(int id) {
+        if (id >= nodeCount) {
+            if ((id >> SHIFT) >= bits.length) {
+                grow();
+            } else {
+                nodeCount = id + 1;
+            }
+        }
+    }
+
+    public void clearAll() {
+        Arrays.fill(bits, 0);
+    }
+
+    public void intersect(NodeBitMap other) {
+        assert graph() == other.graph();
+        int commonLength = Math.min(bits.length, other.bits.length);
+        for (int i = commonLength; i < bits.length; i++) {
+            bits[i] = 0;
+        }
+        for (int i = 0; i < commonLength; i++) {
+            bits[i] &= other.bits[i];
+        }
+    }
+
+    public void subtract(NodeBitMap other) {
+        assert graph() == other.graph();
+        int commonLength = Math.min(bits.length, other.bits.length);
+        for (int i = 0; i < commonLength; i++) {
+            bits[i] &= ~other.bits[i];
+        }
+    }
+
+    public void union(NodeBitMap other) {
+        assert graph() == other.graph();
+        grow();
+        if (bits.length < other.bits.length) {
+            bits = Arrays.copyOf(bits, other.bits.length);
+        }
+        for (int i = 0; i < bits.length; i++) {
+            bits[i] |= other.bits[i];
+        }
+    }
+
+    public void grow() {
+        nodeCount = Math.max(nodeCount, graph().nodeIdCount());
+        int newLength = sizeForNodeCount(nodeCount);
+        if (newLength > bits.length) {
+            newLength = Math.max(newLength, (bits.length * 3 / 2) + 1);
+            bits = Arrays.copyOf(bits, newLength);
+        }
+    }
+
+    private boolean check(Node node, boolean grow) {
+        assert node.graph() == graph() : "this node is not part of the graph: " + node;
+        assert grow || !isNew(node) : "node was added to the graph after creating the node bitmap: " + node;
+        assert node.isAlive() : "node is deleted!" + node;
+        return true;
+    }
+
+    public <T extends Node> void markAll(Iterable<T> nodes) {
+        for (Node node : nodes) {
+            mark(node);
+        }
+    }
+
+    private static class MarkedNodeIterator implements Iterator<Node> {
+
+        private final NodeBitMap visited;
+        private Iterator<Node> nodes;
+        private Node nextNode;
+
+        MarkedNodeIterator(NodeBitMap visited, Iterator<Node> nodes) {
+            this.visited = visited;
+            this.nodes = nodes;
+            forward();
+        }
+
+        private void forward() {
+            do {
+                if (!nodes.hasNext()) {
+                    nextNode = null;
+                    return;
+                }
+                nextNode = nodes.next();
+                if (visited.isNew(nextNode)) {
+                    nextNode = null;
+                    return;
+                }
+            } while (!visited.isMarked(nextNode));
+        }
+
+        @Override
+        public boolean hasNext() {
+            return nextNode != null;
+        }
+
+        @Override
+        public Node next() {
+            try {
+                return nextNode;
+            } finally {
+                forward();
+            }
+        }
+
+        @Override
+        public void remove() {
+            throw new UnsupportedOperationException();
+        }
+
+    }
+
+    @Override
+    public Iterator<Node> iterator() {
+        return new MarkedNodeIterator(NodeBitMap.this, graph().getNodes().iterator());
+    }
+
+    public NodeBitMap copy() {
+        return new NodeBitMap(this);
+    }
+
+    @Override
+    public int count() {
+        int count = 0;
+        for (long l : bits) {
+            count += Long.bitCount(l);
+        }
+        return count;
+    }
+
+    @Override
+    public boolean contains(Node node) {
+        return isMarked(node);
+    }
+
+    @Override
+    public String toString() {
+        return snapshot().toString();
+    }
+}