/* * Copyright (c) 2024, 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 8316756 * @summary Test UNSAFE.copyMemory in combination with Escape Analysis * @library /test/lib * * @modules java.base/jdk.internal.misc * * @run main/othervm -XX:-TieredCompilation -Xbatch -XX:CompileCommand=quiet -XX:CompileCommand=compileonly,compiler.unsafe.UnsafeArrayCopy::test* * compiler.unsafe.UnsafeArrayCopy */ package compiler.unsafe; import java.lang.reflect.*; import java.util.*; import jdk.internal.misc.Unsafe; public class UnsafeArrayCopy { private static Unsafe UNSAFE = Unsafe.getUnsafe(); static long SRC_BASE = UNSAFE.allocateMemory(4); static long DST_BASE = UNSAFE.allocateMemory(4); static class MyClass { int x; } static int test() { MyClass obj = new MyClass(); // Non-escaping to trigger Escape Analysis UNSAFE.copyMemory(null, SRC_BASE, null, DST_BASE, 4); obj.x = 42; return obj.x; } static int[] test2() { int[] src = new int[4]; int[] dst = new int[4]; MyClass obj = new MyClass(); UNSAFE.copyMemory(src, 0, dst, 0, 4); obj.x = 42; dst[1] = obj.x; return dst; } public static void main(String[] args) { for (int i = 0; i < 50_000; ++i) { test(); test2(); } } }