1 /* 2 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 /** 25 * @test 26 * @bug 8214994 27 * @summary The split-if optimization fails because an unexpected Opaque1 is encountered. 28 * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:-UseOnStackReplacement -XX:-BackgroundCompilation 29 * compiler.loopopts.TestSplitIfOpaque1 30 */ 31 32 package compiler.loopopts; 33 34 public class TestSplitIfOpaque1 { 35 36 static class MyClass { 37 int f; MyClass(int f)38 MyClass(int f) { 39 this.f = f; 40 } 41 } 42 43 // The inner loop is found to be a counted loop and a loop limit check 44 // is added by updating the Opaque1 input of the predicate template. 45 // This Opaque1 node is then pushed upwards to before the predicates of 46 // the outer loop and ends up right after the second 'if (b)'. 47 // The split-if optimization kicks in and splits the first predicate of 48 // the outer loop (an "obj != NULL" check) through the 'if (b)' region. 49 // We fail because the region contains an unexpected Opaque1 node. test1(boolean b, int limit, MyClass obj)50 static int test1(boolean b, int limit, MyClass obj) { 51 int res = 0; 52 MyClass notNull = new MyClass(42); 53 if (b) { 54 limit = 100; 55 } 56 if (b) { 57 obj = notNull; 58 } 59 for (int i = 0; i < 1000; ++i) { 60 res += obj.f; 61 for (int j = 0; j <= limit; ++j) { 62 // Empty 63 } 64 } 65 return res; 66 } 67 68 // Same as test1 but triggers slightly different failure mode test2(boolean b, int limit, MyClass obj, int[] array)69 static int test2(boolean b, int limit, MyClass obj, int[] array) { 70 int res = 0; 71 MyClass notNull = new MyClass(12); 72 if (b) { 73 limit = 100; 74 } 75 if (b) { 76 obj = notNull; 77 } 78 for (int i = 0; i < 1000; ++i) { 79 res += obj.f; 80 for (int j = 0; j <= limit; ++j) { 81 array[j] = j; 82 } 83 } 84 return res; 85 } 86 main(String[] args)87 public static void main(String[] args) { 88 MyClass obj = new MyClass(42); 89 int[] array = new int[101]; 90 for (int i = 0; i < 20_000; i++) { 91 test1(true, 50, obj); 92 test1(false, 100, obj); 93 test2(true, 50, obj, array); 94 test2(false, 100, obj, array); 95 } 96 } 97 } 98