jdk/test/hotspot/jtreg/compiler/c2/TestAllocatePrefetchStyleLargeFlags.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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/*
 * @test
 * @summary Stress allocation prefetch with large legal AllocatePrefetch* values
 * @requires vm.compiler2.enabled
 *
 * @run main/othervm -Xbatch -XX:-TieredCompilation -XX:+UseTLAB
 *                   -XX:AllocatePrefetchStyle=1
 *                   -XX:AllocatePrefetchDistance=512
 *                   -XX:AllocatePrefetchStepSize=512
 *                   -XX:AllocatePrefetchLines=64
 *                   -XX:AllocateInstancePrefetchLines=64
 *                   compiler.c2.TestAllocatePrefetchStyleLargeFlags
 * @run main/othervm -Xbatch -XX:-TieredCompilation -XX:+UseTLAB
 *                   -XX:AllocatePrefetchStyle=2
 *                   -XX:AllocatePrefetchDistance=512
 *                   -XX:AllocatePrefetchStepSize=512
 *                   -XX:AllocatePrefetchLines=64
 *                   -XX:AllocateInstancePrefetchLines=64
 *                   compiler.c2.TestAllocatePrefetchStyleLargeFlags
 * @run main/othervm -Xbatch -XX:-TieredCompilation -XX:+UseTLAB
 *                   -XX:AllocatePrefetchStyle=3
 *                   -XX:AllocatePrefetchDistance=512
 *                   -XX:AllocatePrefetchStepSize=512
 *                   -XX:AllocatePrefetchLines=64
 *                   -XX:AllocateInstancePrefetchLines=64
 *                   compiler.c2.TestAllocatePrefetchStyleLargeFlags
 */

package compiler.c2;

public class TestAllocatePrefetchStyleLargeFlags {
    private static volatile Object sink;

    private static final class Payload {
        private final int value;

        private Payload(int value) {
            this.value = value;
        }
    }

    private static Object allocateInstance(int value) {
        return new Payload(value);
    }

    private static Object allocateArray(int value) {
        return new int[value & 31];
    }

    public static void main(String[] args) {
        for (int i = 0; i < 50_000; i++) {
            sink = allocateInstance(i);
            sink = allocateArray(i);
        }
    }
}