--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/compiler/membars/DekkerTest.java	Fri Jul 12 14:03:10 2013 -0700
@@ -0,0 +1,163 @@
+/*
+ * Copyright 2013 SAP AG.  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.
+ */
+
+/**
+ * @test
+ * @bug 8007898
+ * @summary Incorrect optimization of Memory Barriers in Matcher::post_store_load_barrier().
+ * @run main/othervm -Xbatch -XX:+IgnoreUnrecognizedVMOptions -XX:CICompilerCount=1 -XX:+StressGCM -XX:+StressLCM DekkerTest
+ * @run main/othervm -Xbatch -XX:+IgnoreUnrecognizedVMOptions -XX:CICompilerCount=1 -XX:+StressGCM -XX:+StressLCM DekkerTest
+ * @run main/othervm -Xbatch -XX:+IgnoreUnrecognizedVMOptions -XX:CICompilerCount=1 -XX:+StressGCM -XX:+StressLCM DekkerTest
+ * @author Martin Doerr martin DOT doerr AT sap DOT com
+ *
+ * Run 3 times since the failure is intermittent.
+ */
+
+public class DekkerTest {
+
+    /*
+      Read After Write Test (basically a simple Dekker test with volatile variables)
+      Derived from the original jcstress test, available at:
+        http://hg.openjdk.java.net/code-tools/jcstress/file/6c339a5aa00d/
+        tests-custom/src/main/java/org/openjdk/jcstress/tests/volatiles/DekkerTest.java
+     */
+
+    static final int ITERATIONS = 1000000;
+
+    static class TestData {
+        public volatile int a;
+        public volatile int b;
+    }
+
+    static class ResultData {
+        public int a;
+        public int b;
+    }
+
+    TestData[]   testDataArray;
+    ResultData[] results;
+
+    volatile boolean start;
+
+    public DekkerTest() {
+        testDataArray = new TestData[ITERATIONS];
+        results = new ResultData[ITERATIONS];
+        for (int i = 0; i < ITERATIONS; ++i) {
+            testDataArray[i] = new TestData();
+            results[i] = new ResultData();
+        }
+        start = false;
+    }
+
+    public void reset() {
+        for (int i = 0; i < ITERATIONS; ++i) {
+            testDataArray[i].a = 0;
+            testDataArray[i].b = 0;
+            results[i].a = 0;
+            results[i].b = 0;
+        }
+        start = false;
+    }
+
+    int actor1(TestData t) {
+        t.a = 1;
+        return t.b;
+    }
+
+    int actor2(TestData t) {
+        t.b = 1;
+        return t.a;
+    }
+
+    class Runner1 extends Thread {
+        public void run() {
+            do {} while (!start);
+            for (int i = 0; i < ITERATIONS; ++i) {
+                results[i].a = actor1(testDataArray[i]);
+            }
+        }
+    }
+
+    class Runner2 extends Thread {
+        public void run() {
+            do {} while (!start);
+            for (int i = 0; i < ITERATIONS; ++i) {
+                results[i].b = actor2(testDataArray[i]);
+            }
+        }
+    }
+
+    void testRunner() {
+        Thread thread1 = new Runner1();
+        Thread thread2 = new Runner2();
+        thread1.start();
+        thread2.start();
+        do {} while (!thread1.isAlive());
+        do {} while (!thread2.isAlive());
+        start = true;
+        Thread.yield();
+        try {
+            thread1.join();
+            thread2.join();
+        } catch (InterruptedException e) {
+            System.out.println("interrupted!");
+            System.exit(1);
+        }
+    }
+
+    boolean printResult() {
+        int[] count = new int[4];
+        for (int i = 0; i < ITERATIONS; ++i) {
+            int event_kind = (results[i].a << 1) + results[i].b;
+            ++count[event_kind];
+        }
+        if (count[0] == 0 && count[3] == 0) {
+            System.out.println("[not interesting]");
+            return false; // not interesting
+        }
+        String error = (count[0] == 0) ? " ok" : " disallowed!";
+        System.out.println("[0,0] " + count[0] + error);
+        System.out.println("[0,1] " + count[1]);
+        System.out.println("[1,0] " + count[2]);
+        System.out.println("[1,1] " + count[3]);
+        return (count[0] != 0);
+    }
+
+    public static void main(String args[]) {
+        DekkerTest test = new DekkerTest();
+        final int runs = 30;
+        int failed = 0;
+        for (int c = 0; c < runs; ++c) {
+            test.testRunner();
+            if (test.printResult()) {
+                failed++;
+            }
+            test.reset();
+        }
+        if (failed > 0) {
+            throw new InternalError("FAILED. Got " + failed + " failed ITERATIONS");
+        }
+        System.out.println("PASSED.");
+    }
+
+}