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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package org.openjdk.bench.valhalla.ackermann;

import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.OperationsPerInvocation;

public class Identity extends AckermannBase {

    private static IdentityLong ack_identity(IdentityLong x, IdentityLong y) {
        return x.value() == 0 ?
                IdentityLong.valueOf(y.value() + 1) :
                (y.value() == 0 ?
                        ack_identity(IdentityLong.valueOf(x.value() - 1), IdentityLong.valueOf(1)) :
                        ack_identity(IdentityLong.valueOf(x.value() - 1), ack_identity(x, IdentityLong.valueOf(y.value() - 1))));
    }

    @Benchmark
    @OperationsPerInvocation(OPI)
    public long ackermann() {
        return ack_identity(IdentityLong.valueOf(X1), IdentityLong.valueOf(Y1)).value()
                + ack_identity(IdentityLong.valueOf(X2), IdentityLong.valueOf(Y2)).value()
                + ack_identity(IdentityLong.valueOf(X3), IdentityLong.valueOf(Y3)).value();
    }

    public static class IdentityLong {

        public final long v0;

        public IdentityLong(long v0) {
            this.v0 = v0;
        }

        public long value() {
            return v0;
        }

        public static IdentityLong valueOf(long value) {
            return new IdentityLong(value);
        }

    }

}
