1 /*
 2  * Copyright (c) 2022, 2024 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 8284848
27  * @requires vm.compiler2.enabled
28  * @summary Blackhole arguments are globally escaping, thus preventing advanced EA optimizations
29  * @library /test/lib /
30  * @run driver compiler.c2.irTests.blackhole.BlackholeSyncEATest
31  */
32 
33 package compiler.c2.irTests.blackhole;
34 
35 import compiler.lib.ir_framework.*;
36 import jdk.test.lib.Asserts;
37 
38 public class BlackholeSyncEATest {
39 
40     public static void main(String[] args) {
41         // Turn off PEA or it will elide the lock of synchronized (o){} before escaping.
42         TestFramework.runWithFlags(
43             "-XX:+UnlockExperimentalVMOptions",
44             "-XX:-DoPartialEscapeAnalysis",
45             "-XX:CompileCommand=blackhole,compiler.c2.irTests.blackhole.BlackholeSyncEATest::blackhole",
46             "-XX:CompileCommand=dontinline,compiler.c2.irTests.blackhole.BlackholeSyncEATest::dontinline"
47         );
48     }
49 
50     /*
51      * Negative test: check that dontinline method still allows EA to eliminate the synchronization.
52      */
53 
54     @Test
55     @IR(failOn = {IRNode.FAST_LOCK, IRNode.FAST_UNLOCK})
56     static void testDontline() {
57         Object o = new Object();
58         synchronized (o) {}
59         dontinline(o);
60     }
61 
62     static void dontinline(Object o) {}
63 
64     @Run(test = "testDontline")
65     static void runDontinline() {
66         testDontline();
67     }
68 
69     /*
70      * Positive test: check that blackhole keeps the synchronization in.
71      */
72 
73     @Test
74     @IR(counts = {IRNode.FAST_LOCK, "1"})
75     @IR(counts = {IRNode.FAST_UNLOCK, "1"})
76     static void testBlackholed() {
77         Object o = new Object();
78         synchronized (o) {}
79         blackhole(o);
80     }
81 
82     static void blackhole(Object o) {}
83 
84     @Run(test = "testBlackholed")
85     static void runBlackholed() {
86         testBlackholed();
87     }
88 
89 }