1 /*
 2  * Copyright (c) 2018, 2022, Oracle and/or its affiliates. All rights reserved.
 3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 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
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23  */
24 
25 /*
26  * @test
27  * @summary Use a shared string allocated in a humongous G1 region.
28  * @comment -- the following implies that G1 is used (by command-line or by default)
29  * @requires vm.cds.write.archived.java.heap
30  * @requires vm.gc.G1
31  *
32  * @library /test/hotspot/jtreg/runtime/cds/appcds /test/lib
33  * @build HelloString
34  * @build jdk.test.whitebox.WhiteBox
35  * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
36  * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:. SharedStringsHumongous
37  */
38 import java.io.File;
39 import java.io.FileOutputStream;
40 import java.io.OutputStreamWriter;
41 import java.io.PrintWriter;
42 import jdk.test.whitebox.WhiteBox;
43 import jdk.test.lib.cds.CDSTestUtils;
44 import jdk.test.lib.process.OutputAnalyzer;
45 import jdk.test.lib.process.ProcessTools;
46 import jdk.test.lib.Asserts;
47 
48 public class SharedStringsHumongous {
49     static String sharedArchiveConfigFile = CDSTestUtils.getOutputDir() + File.separator + "SharedStringsHumongous_gen.txt";
50 
51     public static void main(String[] args) throws Exception {
52         WhiteBox wb = WhiteBox.getWhiteBox();
53 
54         try (FileOutputStream fos = new FileOutputStream(sharedArchiveConfigFile)) {
55             PrintWriter out = new PrintWriter(new OutputStreamWriter(fos));
56             out.println("VERSION: 1.0");
57             out.println("@SECTION: String");
58             out.println("31: shared_test_string_unique_14325");
59             int region_size = wb.g1RegionSize();
60             char body[] = new char[region_size + region_size / 2];
61             for (int i = 0; i < body.length; i++) {
62               body[i] = 'x';
63             }
64             Asserts.assertTrue(wb.g1IsHumongous(body));
65             String prefix = "generated_string (followed by " + body.length + " 'x') ";
66 
67             System.out.println("G1 region size: " + region_size);
68             System.out.println("Using a humongous string: " + prefix);
69 
70             String s = prefix + new String(body);
71             out.println(s.length() + ": " + s);
72             out.close();
73         }
74 
75         SharedStringsUtils.run(args, SharedStringsHumongous::test);
76     }
77 
78     public static void test(String[] args) throws Exception {
79         String vmOptionsPrefix[] = SharedStringsUtils.getChildVMOptionsPrefix();
80         String appJar = JarBuilder.build("SharedStringsHumongous", "HelloString");
81 
82         OutputAnalyzer dumpOutput = TestCommon.dump(appJar, TestCommon.list("HelloString"),
83                 TestCommon.concat(vmOptionsPrefix,
84                     "-XX:SharedArchiveConfigFile=" + sharedArchiveConfigFile,
85                     "-Xlog:gc+region+cds",
86                     "-Xlog:gc+region=trace"));
87         TestCommon.checkDump(dumpOutput, "extra interned string ignored; size too large");
88         // Extra strings that are humongous are not kept alive, so they should be GC'ed
89         // before dumping the string table. That means the heap should contain no
90         // humongous regions.
91         dumpOutput.shouldNotMatch("gc,region,cds. G1HeapRegion 0x[0-9a-f]* HUM");
92 
93         OutputAnalyzer execOutput = TestCommon.exec(appJar,
94             TestCommon.concat(vmOptionsPrefix, "HelloString"));
95         TestCommon.checkExec(execOutput);
96     }
97 }