using System;

using BenchmarkDotNet.Running;

using BenchmarkDotNet.Configs;

using BenchmarkDotNet.Attributes;

using BenchmarkDotNet.Jobs;

using BenchmarkDotNet.Toolchains.InProcess.Emit;

using BenchmarkDotNet.Loggers;

using Perfolizer.Horology;

​

​

[assembly: System.Diagnostics.Debuggable(isJITTrackingEnabled: false, isJITOptimizerDisabled: false)]

​

BenchmarkRunner.Run<Benchmark>(DefaultConfig.Instance

    .AddJob(Job.Default

        .WithToolchain(new InProcessEmitToolchain(

            timeout: TimeSpan.FromSeconds(30),

            logOutput: false))

        .WithIterationTime(TimeInterval.FromMilliseconds(20)))

    .AddLogger(new ConsoleLogger(unicodeSupport: true, ConsoleLogger.CreateGrayScheme()))

    .WithOptions(ConfigOptions.DisableLogFile));

​

[MemoryDiagnoser]

public class Benchmark

{

    private const int N = 500;

    private int[] array1D = new int[N*N];

    private int[,] arrayMultiDim = new int[N,N];

    private int[][] arrayJagged = new int[N][];

​

    private Random rnd = new Random();

​

    private const int nbIndexToBenchmark = 1000000;

    private (int, int)[] indexToBenchmark = new (int, int)[nbIndexToBenchmark];

​

    [GlobalSetup]

    public void Setup()

    {

        for(int i = 0; i < N ; i++)

        {

            arrayJagged[i] = new int[N];

            for(int j = 0; j < N ; j++)

            {

                int x = rnd.Next();

                array1D[i*N + j] = x;

                arrayMultiDim[i,j] = x;

                arrayJagged[i][j] = x;

            }

        }

​

        for(int i = 0; i < nbIndexToBenchmark ; i++)

        {

            indexToBenchmark[i] = (rnd.Next(N), rnd.Next(N));

        }

    }

​

    [Benchmark]

    public void ReadArray1D() 

    { 

        foreach((int i, int j) in indexToBenchmark) 

        { 

            var a = array1D[i*N + j];

            var b = array1D[j*N + i];

            array1D[i*N + j] = b;

            array1D[j*N + i] = a;

        }

    }

    [Benchmark]

    public void ReadArrayMultiDim() 

    { 

        foreach((int i, int j) in indexToBenchmark) 

        { 

            var a = arrayMultiDim[i,j];

            var b = arrayMultiDim[j,i];

            arrayMultiDim[i,j] = b;

            arrayMultiDim[j,i] = a;

        } 

    }

​

    [Benchmark]

    public void ReadArrayJagged() 

    { 

        foreach((int i, int j) in indexToBenchmark) 

        { 

            var a = arrayJagged[i][j];

            var b = arrayJagged[j][i];

            arrayJagged[i][j] = b;

            arrayJagged[j][i] = a;

        } 

    }

}

​

​