--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jvmci/jdk.vm.ci.common/src/jdk/vm/ci/common/InitTimer.java	Thu May 12 20:57:31 2016 +0200
@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2014, 2015, 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 jdk.vm.ci.common;
+
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * A facility for timing a step in the runtime initialization sequence. This is independent from all
+ * other JVMCI code so as to not perturb the initialization sequence. It is enabled by setting the
+ * {@code "jvmci.inittimer"} system property to {@code "true"}.
+ */
+public final class InitTimer implements AutoCloseable {
+    final String name;
+    final long start;
+
+    private InitTimer(String name) {
+        int n = nesting.getAndIncrement();
+        if (n == 0) {
+            initializingThread = Thread.currentThread();
+            System.out.println("INITIALIZING THREAD: " + initializingThread);
+        } else {
+            assert Thread.currentThread() == initializingThread : Thread.currentThread() + " != " + initializingThread;
+        }
+        this.name = name;
+        this.start = System.currentTimeMillis();
+        System.out.println("START: " + SPACES.substring(0, n * 2) + name);
+    }
+
+    @SuppressFBWarnings(value = "ST_WRITE_TO_STATIC_FROM_INSTANCE_METHOD", justification = "only the initializing thread accesses this field")
+    public void close() {
+        final long end = System.currentTimeMillis();
+        int n = nesting.decrementAndGet();
+        System.out.println(" DONE: " + SPACES.substring(0, n * 2) + name + " [" + (end - start) + " ms]");
+        if (n == 0) {
+            initializingThread = null;
+        }
+    }
+
+    public static InitTimer timer(String name) {
+        return ENABLED ? new InitTimer(name) : null;
+    }
+
+    public static InitTimer timer(String name, Object suffix) {
+        return ENABLED ? new InitTimer(name + suffix) : null;
+    }
+
+    /**
+     * Specifies if initialization timing is enabled.
+     */
+    private static final boolean ENABLED = Boolean.getBoolean("jvmci.InitTimer");
+
+    public static final AtomicInteger nesting = ENABLED ? new AtomicInteger() : null;
+    public static final String SPACES = "                                            ";
+
+    /**
+     * Used to assert the invariant that all related initialization happens on the same thread.
+     */
+    public static Thread initializingThread;
+}