/* * Copyright (c) 2025, 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 8369898 * @summary Bug in PhaseIdealLoop::create_new_if_for_multiversion, that messed up the * _loop_or_ctrl data structure while doing SuperWord for a first loop, and * then get_ctrl asserted for a second loop that was also SuperWord-ed in the * same loop-opts-phase. * @run main/othervm * -XX:CompileCommand=compileonly,*TestMultiversionSlowProjReplacementAndGetCtrl::test * -XX:CompileCommand=exclude,*TestMultiversionSlowProjReplacementAndGetCtrl::dontinline * -XX:-TieredCompilation * -Xbatch * compiler.loopopts.superword.TestMultiversionSlowProjReplacementAndGetCtrl * @run main compiler.loopopts.superword.TestMultiversionSlowProjReplacementAndGetCtrl */ package compiler.loopopts.superword; public class TestMultiversionSlowProjReplacementAndGetCtrl { static final int N = 400; static void dontinline() {} static long test() { int x = 0; int arrayI[] = new int[N]; byte[] arrayB = new byte[N]; dontinline(); // CallStaticJava for dontinline // -> memory Proj // -> it is used in both the k-indexed and j-indexed loops by their loads/stores. for (int k = 8; k < 92; ++k) { // Loop here is multiversioned, and eventually we insert an aliasing runtime check. // This means that a StoreN (with mem input Proj from above) has its ctrl changed // from the old multiversion_if_proj to a new region. We have to be careful to update // the _loop_or_ctrl side-table so that get_ctrl for StoreN is sane. // // Below is some nested loop material I could not reduce further. Maybe because // of loop-opts phase timing. Because we have to SuperWord the k-indexed loop // above in the same loop-opts-phase as the j-indexed loop below, so that they // have a shared _loop_or_ctrl data structure. int y = 6; while (--y > 0) {} for (long i = 1; i < 6; i++) { // I suspect that it is the two array references below that are SuperWord-ed, // and since we do not manage to statically prove they cannot overlap, we add // a speculative runtime check, i.e. multiversioning in this case. arrayI[0] += 1; arrayI[k] = 0; try { x = 2 / k % y; } catch (ArithmeticException a_e) { } } } long sum = 0; for (int j = 0; j < arrayB.length; j++) { // Load below has mem input from Proj below dontinline // We look up to the mem input (Proj), and down to uses // that are Stores, checking in_bb on them, which calls // get_ctrl on that StoreN from the other loop above. sum += arrayB[j]; } return sum; } public static void main(String[] strArr) { for (int i = 0; i < 1_000; i++) { test(); } } }