--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/debug/DynamicCounterNode.java	Wed Mar 20 13:41:44 2013 +0100
@@ -0,0 +1,120 @@
+/*
+ * 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.graal.nodes.debug;
+
+import java.util.*;
+
+import com.oracle.graal.api.meta.*;
+import com.oracle.graal.graph.*;
+import com.oracle.graal.nodes.*;
+import com.oracle.graal.nodes.calc.*;
+import com.oracle.graal.nodes.java.*;
+import com.oracle.graal.nodes.spi.*;
+import com.oracle.graal.nodes.type.*;
+
+/**
+ * This node can be used to add a counter to the code that will estimate the dynamic number of calls
+ * by adding an increment to the compiled code. This should of course only be used for
+ * debugging/testing purposes, and is not 100% accurate (because of concurrency issues while
+ * accessing the counters).
+ * 
+ * A unique counter will be created for each unique String passed to the constructor.
+ */
+public class DynamicCounterNode extends FixedWithNextNode implements Lowerable {
+
+    private static final int MAX_COUNTERS = 10 * 1024;
+    private static final long[] COUNTERS = new long[MAX_COUNTERS];
+    private static final HashMap<String, Integer> INDEXES = new HashMap<>();
+    private final String name;
+    private final boolean addContext;
+
+    public DynamicCounterNode(String name, boolean addContext) {
+        super(StampFactory.forVoid());
+        this.name = name;
+        this.addContext = addContext;
+    }
+
+    private static synchronized int getIndex(String name) {
+        Integer index = INDEXES.get(name);
+        if (index == null) {
+            index = INDEXES.size();
+            if (index == 0) {
+                Runtime.getRuntime().addShutdownHook(new Thread() {
+
+                    @Override
+                    public void run() {
+                        dump();
+                    }
+                });
+            }
+            INDEXES.put(name, index);
+            if (index >= MAX_COUNTERS) {
+                throw new GraalInternalError("too many dynamic counters");
+            }
+            return index;
+        } else {
+            return index;
+        }
+    }
+
+    private static synchronized void dump() {
+        TreeMap<Long, String> sorted = new TreeMap<>();
+
+        long sum = 0;
+        for (int i = 0; i < MAX_COUNTERS; i++) {
+            sum += COUNTERS[i];
+        }
+        int cnt = 0;
+        for (Map.Entry<String, Integer> entry : INDEXES.entrySet()) {
+            sorted.put(COUNTERS[entry.getValue()] * MAX_COUNTERS + cnt++, entry.getKey());
+        }
+
+        for (Map.Entry<Long, String> entry : sorted.entrySet()) {
+            System.out.println((entry.getKey() / MAX_COUNTERS) + ": " + entry.getValue());
+        }
+        System.out.println(sum + ": total");
+
+    }
+
+    @Override
+    public void lower(LoweringTool tool) {
+        int index = addContext ? getIndex(name + " @ " + MetaUtil.format("%h.%n", ((StructuredGraph) graph()).method())) : getIndex(name);
+
+        StructuredGraph graph = (StructuredGraph) graph();
+        ConstantNode arrayConstant = ConstantNode.forObject(COUNTERS, tool.getRuntime(), graph);
+        ConstantNode indexConstant = ConstantNode.forInt(index, graph);
+        LoadIndexedNode load = graph.add(new LoadIndexedNode(arrayConstant, indexConstant, Kind.Long));
+        IntegerAddNode add = graph.add(new IntegerAddNode(Kind.Long, load, ConstantNode.forLong(1, graph)));
+        StoreIndexedNode store = graph.add(new StoreIndexedNode(arrayConstant, indexConstant, Kind.Long, add));
+
+        graph.addBeforeFixed(this, load);
+        graph.addBeforeFixed(this, store);
+        graph.removeFixed(this);
+    }
+
+    public static void createCounter(String name, FixedNode before, boolean addContext) {
+        StructuredGraph graph = (StructuredGraph) before.graph();
+        DynamicCounterNode counter = graph.add(new DynamicCounterNode(name, addContext));
+        graph.addBeforeFixed(before, counter);
+    }
+}