1 /* 2 * Copyright (c) 2010, 2015, 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 /** 26 * @test 27 * @bug 6968348 28 * @summary Byteswapped memory access can point to wrong location after JIT 29 * 30 * @modules java.base/jdk.internal.misc 31 * @run main Test6968348 32 */ 33 34 import jdk.internal.misc.Unsafe; 35 import java.lang.reflect.*; 36 37 public class Test6968348 { 38 static Unsafe unsafe; 39 static final long[] buffer = new long[4096]; 40 static int array_long_base_offset; 41 42 public static void main(String[] args) throws Exception { 43 Class c = Test6968348.class.getClassLoader().loadClass("jdk.internal.misc.Unsafe"); 44 Field f = c.getDeclaredField("theUnsafe"); 45 f.setAccessible(true); 46 unsafe = (Unsafe)f.get(c); 47 array_long_base_offset = unsafe.arrayBaseOffset(long[].class); 48 49 for (int n = 0; n < 100000; n++) { 50 test(); 51 } 52 } 53 54 public static void test() { 55 for (long i = array_long_base_offset; i < 4096; i += 8) { 56 unsafe.putLong(buffer, i, Long.reverseBytes(i)); 57 } 58 } 59 }