/****************************************************************************** * Copyright (c) 2009 - 2015 IBM Corporation. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * IBM Corporation - initial API and implementation *****************************************************************************/ /** * */ package data.causality; /** * Causality test case 11 from * http://www.cs.umd.edu/~pugh/java/memoryModel/CausalityTestCases.html * * <pre> * Initially, x = y = z = 0 * * Thread 1: * r1 = z * w = r1 * r2 = x * y = r2 * * Thread 2: * r4 = w * r3 = y * z = r3 * x = 1 * * Behavior in question: r1 = r2 = r3 = r4 = 1 * * Decision: Allowed. Reordering of independent statements can transform * the code to: * * Thread 1: * r2 = x * y = r2 * r1 = z * w = r1 * * Thread 2: * x = 1 * r3 = y * z = r3 * r4 = w * * after which the behavior in question is SC. * * Note: This is similar to test case 7, but extended with one more * rung in the ladder * </pre> * * * @author etorlak * */ public class Test11 { static int x = 0, y = 0, z = 0, w = 0; public static final void thread1() { final int r1 = z; w = r1; final int r2 = x; y = r2; assert r1==1; assert r2==1; } public static final void thread2() { final int r4 = w; final int r3 = y; z = r3; x = 1; assert r3==1; assert r4==1; } }