/* * Copyright (c) 2020, 2021, 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 8248791 * @summary Test cloning with more than 8 (=ArrayCopyLoadStoreMaxElem) where loads are wrongly replaced by zero. * @requires vm.compiler2.enabled | vm.graal.enabled * * @run main/othervm -XX:-ReduceBulkZeroing * -XX:CompileCommand=dontinline,compiler.arraycopy.TestCloneAccess::* * compiler.arraycopy.TestCloneAccess * @run main/othervm -XX:-ReduceBulkZeroing -XX:-ReduceInitialCardMarks * -XX:CompileCommand=dontinline,compiler.arraycopy.TestCloneAccess::* * compiler.arraycopy.TestCloneAccess */ package compiler.arraycopy; public class TestCloneAccess { static int test(E src) throws CloneNotSupportedException { // ArrayCopyNode for this clone is not inlined since there are more than 8 (=ArrayCopyLoadStoreMaxElem) fields src.i1 = 3; E dest = (E)src.clone(); dontInline(dest.i1, dest.i2); // Both loads are wrongly optimized and replaced by a constant zero. LoadNode::Value() tries to find out if a load // is done from a freshly-allocated object. If that is the case, the load can be replaced by the default value zero. // However, in this case, the Allocation node belongs to an ArrayCopyNode which is responsible for initializing 'dest'. // If -XX:-ReduceBulkZeroing is set, the InitializationNode of the allocation does not bail out of this optimization // which results in a replacement of both loads by zero. This is addressed by this fix. If -XX:+ReduceBulkZeroing is // set, then we already bail out and perform the load correctly. return dest.i1 + dest.i2; } public static void main(String[] args) throws Exception { E e = new E(); e.i2 = 4; int res = 0; for (int i = 0; i < 20000; i++) { res = test(e); if (res != 7 || e.i1 != 3 || e.i2 != 4) { throw new RuntimeException("Wrong result! Expected: res = 7, e.i1 = 3, e.i2 = 4 " + "but got: res = " + res + ", e.i1 = " + e.i1 + ", e.i2 = " + e.i2); } } } // Dont inline this method public static void dontInline(int i1, int i2) { } } class E implements Cloneable { /* * Need more than 8 (=ArrayCopyLoadStoreMaxElem) fields */ int i1; int i2; int i3; int i4; int i5; int i6; int i7; int i8; int i9; E() { i1 = 0; i2 = 1; i3 = 2; i4 = 3; i5 = 4; i6 = 5; i7 = 6; i8 = 7; i9 = 8; } public Object clone() throws CloneNotSupportedException { return super.clone(); } }