package com.arm.test;

import java.util.Random;
import org.openjdk.jmh.annotations.*;
import java.util.concurrent.TimeUnit;

import static java.lang.Math.max;
import static java.lang.Math.min;

@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.MICROSECONDS)
@State(Scope.Benchmark)
public class TestFpMinMaxIntrinsics {

    private static final int SIZE = 1000;
    private float[] fnums;
    private double[] dnums;

    @Setup(Level.Trial)
    public void setupArrays() {
        fnums = new float[SIZE];
        dnums = new double[SIZE];
        Random random = new Random(0);
        for (int i = 0; i < SIZE; i++) {
            fnums[i] = random.nextFloat();
            dnums[i] = random.nextDouble();
        }
    }

    @Benchmark
    public double findDmax() {
        double d0 = dnums[0*4];
        double d1 = dnums[1*4];
        double d2 = dnums[2*4];
        double d3 = dnums[3*4];
        double d4 = dnums[4*4];
        double d5 = dnums[5*4];
        double d6 = dnums[6*4];
        double d7 = dnums[7*4];
        double d8 = dnums[8*4];
        double d9 = dnums[9*4];
        double d10 = dnums[10*4];

        for (int i = 1; i < SIZE; i++) {
            d5 = max(dnums[i], max(d0, max(d1, max(d2, max(d3, max(d4, max(d5, max(d6, max(d7, max(d8, max(d9, d10)))))))))));
            double tmp;
            tmp = d3;  d3 = d10;  d10 = tmp;
            tmp = d7;  d7 = d9;  d9 = tmp;
            tmp = d8;  d8 = d8;  d8 = tmp;
            tmp = d4;  d4 = d7;  d7 = tmp;
            tmp = d4;  d4 = d6;  d6 = tmp;
            tmp = d5;  d5 = d5;  d5 = tmp;
            tmp = d4;  d4 = d4;  d4 = tmp;
            tmp = d1;  d1 = d3;  d3 = tmp;
            tmp = d1;  d1 = d2;  d2 = tmp;
        }
        return d5;
    }


    @Benchmark
    public double findDmin() {
        double d0 = dnums[0*4];
        double d1 = dnums[1*4];
        double d2 = dnums[2*4];
        double d3 = dnums[3*4];
        double d4 = dnums[4*4];
        double d5 = dnums[5*4];
        double d6 = dnums[6*4];
        double d7 = dnums[7*4];
        double d8 = dnums[8*4];
        double d9 = dnums[9*4];
        double d10 = dnums[10*4];

        for (int i = 1; i < SIZE; i++) {
            d5 = min(dnums[i], min(d0, min(d1, min(d2, min(d3, min(d4, min(d5, min(d6, min(d7, min(d8, min(d9, d10)))))))))));
            double tmp;
            tmp = d3;  d3 = d10;  d10 = tmp;
            tmp = d7;  d7 = d9;  d9 = tmp;
            tmp = d8;  d8 = d8;  d8 = tmp;
            tmp = d4;  d4 = d7;  d7 = tmp;
            tmp = d4;  d4 = d6;  d6 = tmp;
            tmp = d5;  d5 = d5;  d5 = tmp;
            tmp = d4;  d4 = d4;  d4 = tmp;
            tmp = d1;  d1 = d3;  d3 = tmp;
            tmp = d1;  d1 = d2;  d2 = tmp;
        }
        return d5;
    }

    @Benchmark
    public float findFmax() {
        float f0 = fnums[0*4];
        float f1 = fnums[1*4];
        float f2 = fnums[2*4];
        float f3 = fnums[3*4];
        float f4 = fnums[4*4];
        float f5 = fnums[5*4];
        float f6 = fnums[6*4];
        float f7 = fnums[7*4];
        float f8 = fnums[8*4];
        float f9 = fnums[9*4];
        float f10 = fnums[10*4];

        for (int i = 1; i < SIZE; i++) {
            f5 = max(fnums[i], max(f0, max(f1, max(f2, max(f3, max(f4, max(f5, max(f6, max(f7, max(f8, max(f9, f10)))))))))));
            float tmp;
            tmp = f3;  f3 = f10;  f10 = tmp;
            tmp = f7;  f7 = f9;  f9 = tmp;
            tmp = f8;  f8 = f8;  f8 = tmp;
            tmp = f4;  f4 = f7;  f7 = tmp;
            tmp = f4;  f4 = f6;  f6 = tmp;
            tmp = f5;  f5 = f5;  f5 = tmp;
            tmp = f4;  f4 = f4;  f4 = tmp;
            tmp = f1;  f1 = f3;  f3 = tmp;
            tmp = f1;  f1 = f2;  f2 = tmp;
        }
        return f5;
    }


    @Benchmark
    public float findFmin() {
        float f0 = fnums[0*4];
        float f1 = fnums[1*4];
        float f2 = fnums[2*4];
        float f3 = fnums[3*4];
        float f4 = fnums[4*4];
        float f5 = fnums[5*4];
        float f6 = fnums[6*4];
        float f7 = fnums[7*4];
        float f8 = fnums[8*4];
        float f9 = fnums[9*4];
        float f10 = fnums[10*4];

        for (int i = 1; i < SIZE; i++) {
            f5 = min(fnums[i], min(f0, min(f1, min(f2, min(f3, min(f4, min(f5, min(f6, min(f7, min(f8, min(f9, f10)))))))))));
            float tmp;
            tmp = f3;  f3 = f10;  f10 = tmp;
            tmp = f7;  f7 = f9;  f9 = tmp;
            tmp = f8;  f8 = f8;  f8 = tmp;
            tmp = f4;  f4 = f7;  f7 = tmp;
            tmp = f4;  f4 = f6;  f6 = tmp;
            tmp = f5;  f5 = f5;  f5 = tmp;
            tmp = f4;  f4 = f4;  f4 = tmp;
            tmp = f1;  f1 = f3;  f3 = tmp;
            tmp = f1;  f1 = f2;  f2 = tmp;
        }
        return f5;
    }

}