1 /*

     2  * Copyright (c) 2018, Red Hat, Inc. 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  * @test

    26  * @bug 8212673

    27  * @summary Node::eqv_uncast() shouldn't step over load barriers unconditionally

    28  * @library /test/lib /

    29  * @modules java.base/jdk.internal.misc

    30  *

    31  * @build sun.hotspot.WhiteBox

    32  * @run driver ClassFileInstaller sun.hotspot.WhiteBox

    33  *                                sun.hotspot.WhiteBox$WhiteBoxPermission

    34  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -XX:-UseOnStackReplacement -XX:-TieredCompilation -XX:-BackgroundCompilation EqvUncastStepOverBarrier

    35  */

    36 

    37 import sun.hotspot.WhiteBox;

    38 import java.lang.reflect.Method;

    39 

    40 public class EqvUncastStepOverBarrier {

    41     static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox();

    42 

    43     private static Object field = new A();

    44 

    45     public static void main(String[] args) throws Exception {

    46         for (int i = 0; i < 20_000; i++) {

    47             test();

    48             test();

    49             test_helper(null, 0);

    50         }

    51         Method m = EqvUncastStepOverBarrier.class.getDeclaredMethod("test");

    52         WHITE_BOX.enqueueMethodForCompilation(m, 4);

    53         if (!WHITE_BOX.isMethodCompiled(m, false)) {

    54             throw new RuntimeException("Method compilation failed");

    55         }

    56     }

    57 

    58     private static Object test() {

    59         Object o = field;

    60         if (o == null) {}

    61         for (int i = 1; i < 100; i *= 2) {

    62             int j = 0;

    63             for (; j < 4; j++) ;

    64             o = test_helper(o, j);

    65         }

    66         return o;

    67     }

    68 

    69     private static Object test_helper(Object o, int j) {

    70         if (j == 4) {

    71             A a = (A) o;

    72             o = a;

    73         } else {

    74             o = new Object();

    75         }

    76         return o;

    77     }

    78 

    79     private static class A {

    80     }

    81 }