/* * Copyright (c) 2023, 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 8308892 * @summary Test that Parse Predicates immediately following other Parse Predicates are cleaned up properly. * @run main/othervm -Xbatch compiler.predicates.TestWrongPredicateOrder */ package compiler.predicates; public class TestWrongPredicateOrder { static boolean flag; static int iFld = 0; static int iFld2 = 34; static int iArr[] = new int[1005]; static int iArr2[] = new int[2]; public static void main(String[] strArr) { // We will keep hitting the Profiled Loop Predicate for RC1 (Integer.MAX_VALUE - 1 - 3 > 1005) such that we will // not emit the Profile Loop Parse Predicate anymore. After that, we will also keep hitting the Loop Limit Check // Predicate (Interger.MAX_VALUE - 1 > Integer.MAX_VALUE - 2) such that we will also not emit the Loop Limit Check // Parse Predicate anymore. As a result, we'll only emit the Loop Parse Predicate in the next re-compilation. // In the next re-compilation, we'll hoist IC1 as Loop Predicate and IC2 as Profiled Loop Predicate. // They have a data dependency between them but this is normally okay because Profiled Loop Predicates are below // Loop Predicates in the graph. But due to the flipped order of Parse Predicates in this bug, we create the // Hoisted Predicates in the wrong order and we end up with a bad graph and assert. for (int i = 0; i < 10000; i++) { flag = !flag; test(); } } public static void test() { // Ensure to emit Loop Limit Check Predicate which is hit too often // -> no Loop Limit Check Parse Predicate is added in re-compilation anymore int limit = flag ? Integer.MAX_VALUE - 1 : 1000; int i = 0; // Loop Limit Check Predicate: limit <= Integer.MAX_VALUE - stride + 1 = Integer.MAX_VALUE - 2 while (i < limit) { i += 3; // Invariant check hoisted as Loop Predicate iArr2[iFld] = 1; // (IC1) if (flag) { // Early exit -> enables Profiled Loop Predicate creation below return; } // Invariant check hoisted as Profiled Loop Predicate // Data dependency on Loop Predicate for "iArr2[0] = 1" iArr2[1] = 5; // (IC2) // Profiled Loop Predicate for range check hit too much -> no Profiled Loop Parse Predicate is added in // re-compilation anymore iArr[i] = 34; // (RC1) if (iFld2 == 5555) { i++; // UCT -> ensures to emit Parse Predicates twice with an If in between that is folded after parsing } } } }