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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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
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 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package org.openjdk.bench.jdk.incubator.foreign;

import jdk.incubator.foreign.MemoryHandles;
import jdk.incubator.foreign.MemorySegment;
import jdk.incubator.foreign.ResourceScope;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Fork;
import org.openjdk.jmh.annotations.Measurement;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Setup;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.annotations.TearDown;
import org.openjdk.jmh.annotations.Warmup;

import java.lang.invoke.VarHandle;
import java.nio.ByteOrder;
import java.util.concurrent.TimeUnit;

import static jdk.incubator.foreign.MemoryLayouts.JAVA_INT;

@BenchmarkMode(Mode.AverageTime)
@Warmup(iterations = 5, time = 500, timeUnit = TimeUnit.MILLISECONDS)
@Measurement(iterations = 10, time = 500, timeUnit = TimeUnit.MILLISECONDS)
@State(org.openjdk.jmh.annotations.Scope.Thread)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@Fork(value = 3, jvmArgsAppend = { "--add-modules", "jdk.incubator.foreign" })
public class VarHandleExact {

    static final VarHandle exact;
    static final VarHandle generic;

    static {
        generic = MemoryHandles.varHandle(int.class, ByteOrder.nativeOrder());
        exact = generic.withInvokeExactBehavior();
    }

    MemorySegment data;

    @Setup
    public void setup() {
        data = MemorySegment.allocateNative(JAVA_INT, ResourceScope.newConfinedScope());
    }

    @TearDown
    public void tearDown() {
        data.scope().close();
    }

    @Benchmark
    public void exact_exactInvocation() {
        exact.set(data, (long) 0, 42);
    }

    @Benchmark
    public void generic_genericInvocation() {
        generic.set(data, 0, 42);
    }

    @Benchmark
    public void generic_exactInvocation() {
        generic.set(data, (long) 0, 42);
    }
}
