--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.jvmci.debug/src/com/oracle/jvmci/debug/DebugTimer.java	Tue May 26 23:21:15 2015 +0200
@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2012, 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.jvmci.debug;
+
+import java.util.concurrent.*;
+
+/**
+ * A timer for some activity of interest. A timer should be deployed using the try-with-resources
+ * pattern:
+ *
+ * <pre>
+ * try (TimerCloseable a = timer.start()) {
+ *     // the code to time
+ * }
+ * </pre>
+ */
+public interface DebugTimer {
+
+    /**
+     * Starts this timer if timing is {@linkplain Debug#isTimeEnabled() enabled} or this is an
+     * {@linkplain #isConditional() unconditional} timer.
+     *
+     * @return an object that must be closed once the activity has completed to add the elapsed time
+     *         since this call to the total for this timer
+     */
+    DebugCloseable start();
+
+    /**
+     * Sets a flag determining if this timer is only enabled if timing is
+     * {@link Debug#isTimeEnabled() enabled}.
+     */
+    void setConditional(boolean flag);
+
+    /**
+     * Determines if this timer is only enabled if timing is {@link Debug#isTimeEnabled() enabled}.
+     */
+    boolean isConditional();
+
+    /**
+     * Gets the current value of this timer.
+     */
+    long getCurrentValue();
+
+    /**
+     * Gets the time unit of this timer.
+     */
+    TimeUnit getTimeUnit();
+
+    /**
+     * Gets the timer recording the amount time spent within a timed scope minus the time spent in
+     * any nested timed scopes.
+     *
+     * @return null if this timer does not support flat timing
+     */
+    default DebugTimer getFlat() {
+        return null;
+    }
+}