--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.max.graal.nodes/src/com/oracle/max/graal/nodes/StructuredGraph.java	Sat Dec 17 19:59:18 2011 +0100
@@ -0,0 +1,126 @@
+/*
+ * Copyright (c) 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 com.oracle.max.graal.nodes;
+
+import java.util.*;
+
+import com.oracle.max.graal.graph.*;
+import com.oracle.max.graal.nodes.java.*;
+
+
+/**
+ * A graph that contains at least one distinguished node : the {@link #start() start} node.
+ * This node is the start of the control flow of the graph.
+ */
+public class StructuredGraph extends Graph {
+    private final BeginNode start;
+
+    /**
+     * Creates a new Graph containing a single {@link BeginNode} as the {@link #start() start} node.
+     */
+    public StructuredGraph(String name) {
+        super(name);
+        this.start = add(new BeginNode());
+    }
+
+    /**
+     * Creates a new Graph containing a single {@link BeginNode} as the {@link #start() start} node.
+     */
+    public StructuredGraph() {
+        this(null);
+    }
+
+    public BeginNode start() {
+        return start;
+    }
+
+    @Override
+    public StructuredGraph copy() {
+        return copy(name);
+    }
+
+    @Override
+    public StructuredGraph copy(String name) {
+        StructuredGraph copy = new StructuredGraph(name);
+        HashMap<Node, Node> replacements = new HashMap<Node, Node>();
+        replacements.put(start, copy.start);
+        copy.addDuplicates(getNodes(), replacements);
+        return copy;
+    }
+
+    public LocalNode getLocal(int index) {
+        for (LocalNode local : getNodes(LocalNode.class)) {
+            if (local.index() == index) {
+                return local;
+            }
+        }
+        return null;
+    }
+
+    public Iterable<Invoke> getInvokes() {
+        final Iterator<MethodCallTargetNode> callTargets = getNodes(MethodCallTargetNode.class).iterator();
+        return new Iterable<Invoke>() {
+            private Invoke next;
+
+            @Override
+            public Iterator<Invoke> iterator() {
+                return new Iterator<Invoke>() {
+
+                    @Override
+                    public boolean hasNext() {
+                        if (next == null) {
+                            while (callTargets.hasNext()) {
+                                Invoke i = callTargets.next().invoke();
+                                if (i != null) {
+                                    next = i;
+                                    return true;
+                                }
+                            }
+                            return false;
+                        } else {
+                            return true;
+                        }
+                    }
+
+                    @Override
+                    public Invoke next() {
+                        try {
+                            return next;
+                        } finally {
+                            next = null;
+                        }
+                    }
+
+                    @Override
+                    public void remove() {
+                        throw new UnsupportedOperationException();
+                    }
+                };
+            }
+        };
+    }
+
+    public boolean hasLoops() {
+        return getNodes(LoopBeginNode.class).iterator().hasNext();
+    }
+}