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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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/**
 * @test
 * @requires vm.cds
 * @requires vm.flagless
 * @requires vm.bits == 64
 * @bug 8376822
 * @summary Allocation gaps in the RW region caused by -XX:+UseCompactObjectHeaders should be reused
 * @library /test/lib
 * @build MetaspaceAllocGaps
 * @run driver jdk.test.lib.helpers.ClassFileInstaller -jar hello.jar Hello
 * @run driver MetaspaceAllocGaps
 */

import jdk.test.lib.cds.SimpleCDSAppTester;
import jdk.test.lib.helpers.ClassFileInstaller;
import jdk.test.lib.process.OutputAnalyzer;

public class MetaspaceAllocGaps {
    public static void main(String[] args) throws Exception {
        String appJar = ClassFileInstaller.getJarPath("hello.jar");
        for (int i = 0; i < 2; i++) {
            String compressedOops = "-XX:" + (i == 0 ? "-" : "+") + "UseCompressedOops";
            SimpleCDSAppTester.of("MetaspaceAllocGaps" + i)
                .addVmArgs("-Xlog:aot=debug,aot+alloc=trace",
                           "-XX:+UseCompactObjectHeaders")
                .classpath(appJar)
                .appCommandLine("Hello")
                .setTrainingChecker((OutputAnalyzer out) -> {
                    // Typically all gaps should be filled. If not, we probably have a regression in C++ class ArchiveUtils.
                    //
                    // [0.422s][debug][aot ] Detailed metadata info (excluding heap region):
                    // [...]
                    // [0.422s][debug][aot ] Gap : 0 0 0.0 | 0 0 0.0 | 0 0 0.0 <<< look for this pattern
                    out.shouldMatch("Allocated [1-9][0-9]+ objects of [1-9][0-9]+ bytes in gaps .remain = 0 bytes")
                       .shouldMatch("debug.* Gap .*0[.]0.*0[.]0.*0[.]0")
                       .shouldNotMatch("Unexpected .* gaps .* for Klass alignment");
                })
                .setProductionChecker((OutputAnalyzer out) -> {
                    out.shouldContain("HelloWorld");
                })
                .runAOTWorkflow();
        }
    }
}

class Hello {
    public static void main(String[] args) {
        System.out.println("HelloWorld");
    }
}