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package org.openjdk.bench.vm.compiler.x86;

import org.openjdk.jmh.annotations.*;

import java.util.concurrent.TimeUnit;

@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@Warmup(iterations = 10, time = 1, timeUnit = TimeUnit.SECONDS)
@Measurement(iterations = 10, time = 1, timeUnit = TimeUnit.SECONDS)
// Fix heap size since the StoreN benchmarks are allocating a lot and dependent on GC selection and compressed oop mode.
@Fork(value = 3, jvmArgsAppend = {"-Xms1g", "-Xmx1g"})
@State(Scope.Thread)
public class RedundantLeaPeephole {
    @State(Scope.Thread)
    public class StoreNHelper {
        Object o1;
        Object o2;

        public StoreNHelper(Object o1, Object o2) {
            this.o1 = o1;
            this.o2 = o2;
        }
    }

    @State(Scope.Thread)
    public class StringEqualsHelper {
        private String str;

        public StringEqualsHelper(String str) {
            this.str = str;
        }

        @CompilerControl(CompilerControl.Mode.INLINE)
        public boolean doEquals(String other) {
            return this.str.equals(other);
        }
    }

    private static final int SIZE = 42;
    private static final int SMALL_IDX = 3;
    private static final int BIG_IDX = 33;

    private static final Object O1 = new Object();
    private static final Object O2 = new Object();

    private Object[] arr1 = new Object[SIZE];
    private Object[] arr2 = new Object[SIZE];
    private StoreNHelper[] arrH1 = new StoreNHelper[SIZE];
    private StoreNHelper[] arrH2 = new StoreNHelper[SIZE];

    private StringEqualsHelper strEqHelper = new StringEqualsHelper("foo");

    @Benchmark
    @Fork(jvmArgsAppend = {"-XX:+UseSerialGC"})
    public void benchStoreNRemoveSpillSerial() {
        this.arrH1[SMALL_IDX] = new StoreNHelper(O1, O2);
        this.arrH2[BIG_IDX] = new StoreNHelper(O2, O1);
    }

    @Benchmark
    @Fork(jvmArgsAppend = {"-XX:+UseParallelGC"})
    public void benchStoreNRemoveSpillParallel() {
        this.arrH1[SMALL_IDX] = new StoreNHelper(O1, O2);
        this.arrH2[BIG_IDX] = new StoreNHelper(O2, O1);
    }

    @Benchmark
    @Fork(jvmArgsAppend = {"-XX:+UseSerialGC"})
    public void benchStoreNNoAllocSerial() {
        this.arr1[SMALL_IDX] = O1;
        this.arr1[BIG_IDX] = O2;
        this.arr2[SMALL_IDX] = O1;
        this.arr2[BIG_IDX] = O2;
    }

    @Benchmark
    @Fork(jvmArgsAppend = {"-XX:+UseParallelGC"})
    public void benchStoreNNoAllocParallel() {
        this.arr1[SMALL_IDX] = O1;
        this.arr1[BIG_IDX] = O2;
        this.arr2[SMALL_IDX] = O1;
        this.arr2[BIG_IDX] = O2;
    }

    @Benchmark
    public boolean benchStringEquals() {
        return this.strEqHelper.doEquals("bar");
    }
}