1 /* 2 * Copyright (c) 2016, 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. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 /* 27 * @test 28 * @summary tests on constant folding of unsafe get operations 29 * @library /testlibrary /test/lib 30 * 31 * @run main/bootclasspath -XX:+UnlockDiagnosticVMOptions 32 * -Xbatch -XX:-TieredCompilation 33 * -XX:+FoldStableValues 34 * UnsafeGetStableArrayElement 35 * 36 * @run main/bootclasspath -XX:+UnlockDiagnosticVMOptions 37 * -Xbatch -XX:+TieredCompilation -XX:TieredStopAtLevel=1 38 * -XX:+FoldStableValues 39 * UnsafeGetStableArrayElement 40 */ 41 import jdk.internal.misc.Unsafe; 42 import jdk.internal.vm.annotation.Stable; 43 import java.util.concurrent.Callable; 44 45 import static jdk.internal.misc.Unsafe.*; 46 import static jdk.test.lib.Asserts.*; 47 48 public class UnsafeGetStableArrayElement { 49 @Stable static final byte[] STABLE_BYTE_ARRAY = new byte[] { 0, 1, -128, 127}; 50 51 static final Unsafe U = Unsafe.getUnsafe(); 52 53 static int testChar() { 54 return U.getChar(STABLE_BYTE_ARRAY, ARRAY_BYTE_BASE_OFFSET + 0 * ARRAY_CHAR_INDEX_SCALE) + 55 U.getChar(STABLE_BYTE_ARRAY, ARRAY_BYTE_BASE_OFFSET + 1 * ARRAY_CHAR_INDEX_SCALE); 56 } 57 58 static void run(Callable c) throws Exception { 59 Object first = c.call(); 60 for (int i = 0; i < 20_000; i++) { 61 assertEQ(first, c.call()); 62 } 63 } 64 65 public static void main(String[] args) throws Exception { 66 run(UnsafeGetStableArrayElement::testChar); 67 } 68 }