| /* |
| * Copyright 2009 D.E. Shaw. 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 6912517 |
| * @summary JIT bug compiles out (and stops running) code that needs to be run. Causes NPE. |
| * |
| * @run main/othervm -Xbatch -XX:CompileThreshold=100 -XX:+IgnoreUnrecognizedVMOptions -XX:-UseCompressedOops |
| * compiler.c2.Test6912517 |
| */ |
| |
| package compiler.c2; |
| |
| /** |
| * Highlights a bug with the JIT compiler. |
| * @author Matt Bruce m b r u c e __\at/__ g m a i l DOT c o m |
| */ |
| public class Test6912517 implements Runnable |
| { |
| private final Thread myThread; |
| private Thread myInitialThread; |
| private boolean myShouldCheckThreads; |
| |
| /** |
| * Sets up the running thread, and starts it. |
| */ |
| public Test6912517(int id) |
| { |
| myThread = new Thread(this); |
| myThread.setName("Runner: " + id); |
| myThread.start(); |
| myShouldCheckThreads = false; |
| } |
| |
| /** |
| * @param shouldCheckThreads the shouldCheckThreads to set |
| */ |
| public void setShouldCheckThreads(boolean shouldCheckThreads) |
| { |
| myShouldCheckThreads = shouldCheckThreads; |
| } |
| |
| /** |
| * Starts up the two threads with enough delay between them for JIT to |
| * kick in. |
| * @param args |
| * @throws InterruptedException |
| */ |
| public static void main(String[] args) throws InterruptedException |
| { |
| // let this run for a bit, so the "run" below is JITTed. |
| for (int id = 0; id < 20; id++) { |
| System.out.println("Starting thread: " + id); |
| Test6912517 bug = new Test6912517(id); |
| bug.setShouldCheckThreads(true); |
| Thread.sleep(2500); |
| } |
| } |
| |
| /** |
| * @see java.lang.Runnable#run() |
| */ |
| public void run() |
| { |
| long runNumber = 0; |
| while (true) { |
| // run hot for a little while, give JIT time to kick in to this loop. |
| // then run less hot. |
| if (runNumber > 15000) { |
| try { |
| Thread.sleep(5); |
| } |
| catch (InterruptedException e) { |
| e.printStackTrace(); |
| } |
| } |
| runNumber++; |
| ensureProperCallingThread(); |
| } |
| } |
| |
| private void ensureProperCallingThread() |
| { |
| // this should never be null. but with the JIT bug, it will be. |
| // JIT BUG IS HERE ==>>>>> |
| if (myShouldCheckThreads) { |
| if (myInitialThread == null) { |
| myInitialThread = Thread.currentThread(); |
| } |
| else if (myInitialThread != Thread.currentThread()) { |
| System.out.println("Not working: " + myInitialThread.getName()); |
| } |
| } |
| } |
| } |