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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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/*
 * @test id=generational
 * @summary Test that growth of old-gen triggers old-gen marking
 * @requires vm.gc.Shenandoah
 * @library /test/lib
 * @run driver TestOldGrowthTriggers
 */

import java.util.*;
import java.math.BigInteger;

import jdk.test.lib.Asserts;
import jdk.test.lib.process.ProcessTools;
import jdk.test.lib.process.OutputAnalyzer;

public class TestOldGrowthTriggers {

    public static void makeOldAllocations() {
        // Expect most of the BigInteger entries placed into array to be promoted, and most will eventually become garbage within old

        final int ArraySize = 512 * 1024;   // 512K entries
        final int BitsInBigInteger = 128;
        final int RefillIterations = 64;
        BigInteger array[] = new BigInteger[ArraySize];
        Random r = new Random(46);

        for (int i = 0; i < ArraySize; i++) {
            array[i] = new BigInteger(BitsInBigInteger, r);
        }

        for (int refillCount = 0; refillCount < RefillIterations; refillCount++) {
            // Each refill repopulates ArraySize randomly selected elements within array
            for (int i = 0; i < ArraySize; i++) {
                int replaceIndex = r.nextInt(ArraySize);
                int deriveIndex = r.nextInt(ArraySize);
                switch (i & 0x3) {
                    case 0:
                        // creates new old BigInteger, releases old BigInteger,
                        // may create ephemeral data while computing gcd
                        array[replaceIndex] = array[replaceIndex].gcd(array[deriveIndex]);
                        break;
                    case 1:
                        // creates new old BigInteger, releases old BigInteger
                        array[replaceIndex] = array[replaceIndex].multiply(array[deriveIndex]);
                        break;
                    case 2,3:
                        // do nothing, let all objects in the array age to increase pressure on old generation
                        break;
                }
            }
        }
    }

    public static void testOld(String... args) throws Exception {
        String[] cmds = Arrays.copyOf(args, args.length + 2);
        cmds[args.length] = TestOldGrowthTriggers.class.getName();
        cmds[args.length + 1] = "test";
        ProcessBuilder pb = ProcessTools.createLimitedTestJavaProcessBuilder(cmds);
        OutputAnalyzer output = new OutputAnalyzer(pb.start());
        output.shouldHaveExitValue(0);
        output.shouldContain("Trigger (Old): Old has overgrown");
    }

    public static void main(String[] args) throws Exception {
        if (args.length > 0 && args[0].equals("test")) {
            makeOldAllocations();
            return;
        }

        testOld("-Xlog:gc",
                "-Xms96m",
                "-Xmx96m",
                "-XX:+UnlockDiagnosticVMOptions",
                "-XX:+UnlockExperimentalVMOptions",
                "-XX:+UseShenandoahGC",
                "-XX:ShenandoahGCMode=generational",
                "-XX:ShenandoahGuaranteedYoungGCInterval=0",
                "-XX:ShenandoahGuaranteedOldGCInterval=0"
        );

        testOld("-Xlog:gc",
                "-Xms96m",
                "-Xmx96m",
                "-XX:+UnlockDiagnosticVMOptions",
                "-XX:+UnlockExperimentalVMOptions",
                "-XX:+UseShenandoahGC",
                "-XX:ShenandoahGCMode=generational",
                "-XX:ShenandoahGuaranteedYoungGCInterval=0",
                "-XX:ShenandoahGuaranteedOldGCInterval=0",
                "-XX:+UseCompactObjectHeaders"
        );
    }
}