view test/compiler/6589834/Test_ia32.java @ 12986:1b422ef5288a

8025728: Missing volatile specifier for field G1AllocRegion::_alloc_region Summary: The field G1AllocRegion::_alloc_region needs to be declared volatile as it is used with that intention. Otherwise the compiler may generate the code that reloads the value which might have changed in the meantime, leading to spurious crashes. Reviewed-by: iveresov, simonis, tschatzl Contributed-by: Axel Siebenborn <axel.siebenborn@sap.com>
author tschatzl
date Wed, 23 Oct 2013 10:23:06 +0200
parents 7369298bec7e
children de6a9e811145
line wrap: on
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/*
 * Copyright (c) 2009, 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.
 */

/**
 * @test
 * @bug 6589834
 * @summary deoptimization problem with -XX:+DeoptimizeALot
 *
 * @run main Test_ia32
 */

/***************************************************************************************
NOTE: The bug shows up (with several "Bug!" message) even without the
      flag -XX:+DeoptimizeALot. In a debug build, you may want to try
      the flags -XX:+VerifyStack and -XX:+DeoptimizeALot to get more information.
****************************************************************************************/
import java.lang.reflect.Constructor;

public class Test_ia32 {

    public static int NUM_THREADS = 100;

    public static int CLONE_LENGTH = 1000;

    public static void main(String[] args) throws InterruptedException, ClassNotFoundException {

        Reflector[] threads = new Reflector[NUM_THREADS];
        for (int i = 0; i < threads.length; i++) {
            threads[i] = new Reflector();
            threads[i].start();
        }

        System.out.println("Give Reflector.run() some time to compile...");
        Thread.sleep(5000);

        System.out.println("Load RMISecurityException causing run() deoptimization");
        ClassLoader.getSystemClassLoader().loadClass("java.rmi.RMISecurityException");

        for (Reflector thread : threads)
            thread.requestStop();

        for (Reflector thread : threads)
            try {
                thread.join();
            } catch (InterruptedException e) {
                System.out.println(e);
            }

    }

}

class Reflector extends Thread {

    volatile boolean _doSpin = true;

    Test_ia32[] _tests;

    Reflector() {
        _tests = new Test_ia32[Test_ia32.CLONE_LENGTH];
        for (int i = 0; i < _tests.length; i++) {
            _tests[i] = new Test_ia32();
        }
    }

    static int g(int i1, int i2, Test_ia32[] arr, int i3, int i4) {

        if (!(i1==1 && i2==2 && i3==3 && i4==4)) {
            System.out.println("Bug!");
        }

        return arr.length;
    }

    static int f(Test_ia32[] arr) {
        return g(1, 2, arr.clone(), 3, 4);
    }

    @Override
    public void run() {
        Constructor[] ctrs = null;
        Class<Test_ia32> klass = Test_ia32.class;
        try {
            ctrs = klass.getConstructors();
        } catch (SecurityException e) {
            System.out.println(e);
        }

        try {
            while (_doSpin) {
                if (f(_tests) < 0)
                    System.out.println("return value usage");
            }
        } catch (NullPointerException e) {
            e.printStackTrace();
        }

        System.out.println(this + " - stopped.");
    }

    public void requestStop() {
        System.out.println(this + " - stop requested.");
        _doSpin = false;
    }

}