using BenchmarkDotNet.Attributes;
using System.Runtime.CompilerServices;

namespace VirtualDispatchChecks
{

    class _1
    {
        public virtual string Method() => "A";
    }

    class _2 : _1
    {
        public override string Method() => "B";
    }

    class _3 : _1
    {
        public override string Method() => "C";
    }

    class _4 : _1
    {
        public override string Method() => "D";
    }

    class _5 : _1
    {
        public override string Method() => "E";
    }
    class _6 : _1
    {
        public override string Method() => "F";
    }
    class _7 : _1
    {
        public override string Method() => "F";
    }

    class _8 : _1
    {
        public override string Method() => "F";
    }

    class _9 : _1
    {
        public override string Method() => "F";
    }

    class _10 : _1
    {
        public override string Method() => "F";
    }

    public class ResolveVirtualRepeatedly
    {
        static _1 _1 = new _1();
        static _1 _2 = new _2();
        static _1 _3 = new _3();
        static _1 _4 = new _4();
        static _1 _5 = new _5();
        static _1 _6 = new _6();
        static _1 _7 = new _7();
        static _1 _8 = new _8();
        static _1 _9 = new _9();
        static _1 _10 = new _10();
        [MethodImpl(MethodImplOptions.NoInlining)]
        static _1 GetA(int index)
        {
            switch (index % 10)
            {
                case 0:
                    return _10;
                case 1: return _1;
                case 2: return _2;
                case 3: return _3;
                case 4: return _4;
                case 5: return _5;
                case 6: return _6;
                case 7: return _7;
                case 8: return _8;
                case 9: return _9;
            }
            return null!;
        }

        [MethodImpl(MethodImplOptions.NoInlining)]
        static Func<string> GetAction(int index)
        {
            return GetA(index).Method;
        }

        [Benchmark]
        public void Get1Virtual()
        {
            GetAction(0);
        }

        [Benchmark]
        public void Get10Virtual()
        {
            GetAction(0);
            GetAction(1);
            GetAction(2);
            GetAction(3);
            GetAction(4);
            GetAction(5);
            GetAction(6);
            GetAction(7);
            GetAction(8);
            GetAction(9);
        }
    }
}