/* * Copyright (c) 2023, Red Hat, Inc. 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 8314024 * @requires vm.compiler2.enabled * @summary Node used in check in main loop sunk from pre loop before RC elimination * @run main/othervm -XX:-BackgroundCompilation -XX:-UseLoopPredicate TestNodeSunkFromPreLoop * */ public class TestNodeSunkFromPreLoop { private static int unusedField; public static void main(String[] args) { A object = new A(); for (int i = 0; i < 20_000; i++) { test(object, 1000, 0); } } private static int test(A object, int stop, int inv) { int res = 0; // pre/main/post loops created for this loop for (int i = 0; i < stop; i++) { // Optimized out. Delay transformation of loop above. for (int j = 0; j < 10; j++) { for (int k = 0; k < 10; k++) { } } // null check in pre loop so field load also in pre loop int v = object.field; int v2 = (v + inv); if (i > 1000) { // never taken. v + inv has a use out of loop at an unc. unusedField = v2; } // transformed in the main loop to i + (v + inv) int v3 = (v + (i + inv)); if (v3 > 1000) { break; } } return res; } private static class A { public int field; } }