/* * Copyright (c) 2002, 2018, 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 * * @summary converted from VM Testbase runtime/jbe/dead/dead03. * VM Testbase keywords: [quick, runtime] * * @library /vmTestbase * /test/lib * @run driver jdk.test.lib.FileInstaller . . * @run main/othervm vm.compiler.jbe.dead.dead03.dead03 */ package vm.compiler.jbe.dead.dead03; /* -- Test the elimination of dead assignment to global variables In the example below, the value assigned to i is never used, all dead stores to global can be eliminated, and the last return statement in f() is unreachable; Both dead/unused stores and unreachable statement can be eliminated. */ public class dead03 { int global; int i; public static void main(String args[]) { dead03 dce = new dead03(); System.out.println("f()="+dce.f()+"; fopt()="+dce.fopt()); if (dce.f() == dce.fopt()) { System.out.println("Test dead03 Passed."); } else { throw new Error("Test dead03 Failed: f()=" + dce.f() + " != fopt()=" + dce.fopt()); } } int f() { i = 1; /* dead store */ global = 8; /* dead store */ global = 7; /* dead store */ global = 6; /* dead store */ global = 5; /* dead store */ global = 4; /* dead store */ global = 3; /* dead store */ global = 2; /* dead store */ global = 1; /* dead store */ global = 0; /* dead store */ global = -1; /* dead store */ global = -2; /* dead store */ i = 1; /* dead store */ global = 8; /* dead store */ global = 7; /* dead store */ global = 6; /* dead store */ global = 5; /* dead store */ global = 4; /* dead store */ global = 3; /* dead store */ global = 2; /* dead store */ global = 1; /* dead store */ global = 0; /* dead store */ global = -1; /* dead store */ global = -2; /* dead store */ i = 1; /* dead store */ global = 8; /* dead store */ global = 7; /* dead store */ global = 6; /* dead store */ global = 5; /* dead store */ global = 4; /* dead store */ global = 3; /* dead store */ global = 2; /* dead store */ global = 1; /* dead store */ global = 0; /* dead store */ global = -1; /* dead store */ global = -2; if (Math.abs(global) >= 0) return global; return global; /* unreachable */ } // Code fragment after dead code elimination int fopt() { global = -2; return global; } }