/* * Copyright (c) 2022, 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 8297951 * @summary Test that crashes because we do not emit skeleton predicates for normal If nodes for which a range check * predicate is created in loop predication. * @requires vm.debug == true & vm.compiler2.enabled * @run main/othervm -XX:-TieredCompilation -Xbatch -XX:-RangeCheckElimination -XX:+BailoutToInterpreterForThrows compiler.loopopts.TestMissingSkeletonPredicateForIfNode */ package compiler.loopopts; public class TestMissingSkeletonPredicateForIfNode { static int iFld = 2, x; static short limit = 10; public static void main(String[] args) throws Exception { for (int i = 0; i < 5000; i++) { try { test(i % 2 == 0, i % 3); } catch (Exception e) { // Expected } } } public static void test(boolean flag, int arg) throws Exception { int sum = 1; int[] iArr2 = new int[4]; RuntimeException r = new RuntimeException(); for (int i = 0; i < limit; i+=2) { // Pre/main/post + Unrolled once. This results in the following type for the iv phi i: [2..SHORT_MAX] x = 5 / sum; if (Integer.compareUnsigned(i, iArr2.length) < 0) { // (**) Loop predication creates a RC predicate for this check // After unrolling, we have: // // iArr2[i] // iArr2[i+2] // // The type of iArr2[i+2] is [4..SHORT_MAX+2] (we need limit to be short such that we do not have an integer overflow // which would set the type to int). However, the type of the CastII node for the index i+2 is [0..3] because its size // is only 4. Since the type of i+2 is outside the range of the CastII node, the CastII node is replaced by top and // some of the data nodes and memory nodes die. We are left with a broken graph and later assert because of that. iFld += iArr2[i]; // RangeCheck node is removed because it shares the same bool as the If (**). sum += iFld; } else { // Emits an UCT with -XX:+BailoutToInterpreterForThrows and therefore the If (**) satisfies the condition of being a // range check if with one of its blocks being an UCT. throw r; } if (i > 50) { break; } } } }