寻找性能更优秀的不可变小字典

using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Reflection;
using BenchmarkDotNet.Attributes;
namespace Newbe.ObjectVisitor.BenchmarkTest
{
    [Config(typeof(Config))]
    public class FuncSearchTest
    {
        private Func<Yueluo, object>[] _target;
        private readonly Yueluo _yueluo;
        private readonly Func<Yueluo, string> _func;
        private readonly PropertyInfo _nameP;
        private readonly Func<PropertyInfo, Func<Yueluo, object>> _switcher;
        private readonly Dictionary<PropertyInfo, Func<Yueluo, object>> _dic;
        public FuncSearchTest()
        {
            _yueluo = Yueluo.Create();
            var propertyInfos = typeof(Yueluo).GetProperties().ToArray();
            CreateCacheArrayD(propertyInfos);
            _switcher = ValueGetter.CreateGetter<Yueluo, object>(propertyInfos,
                info => Expression.SwitchCase(Expression.Constant(CreateFunc(info)), Expression.Constant(info)));
            _dic = propertyInfos.ToDictionary(x => x, CreateFunc);
            _nameP = typeof(Yueluo).GetProperty(nameof(Yueluo.Name));
            _func = x => x.Name;
        }
        private void CreateCacheArrayD(IReadOnlyCollection<PropertyInfo> propertyInfos)
        {
            _target = new Func<Yueluo, object>[propertyInfos.Count];
            foreach (var info in propertyInfos)
            {
                var key = GetKey(info);
                var index = key % propertyInfos.Count;
                _target[index] = CreateFunc(info);
            }
        }
        private static Func<Yueluo, object> CreateFunc(PropertyInfo info)
        {
            var pExp = Expression.Parameter(typeof(Yueluo), "x");
            var bodyExp = Expression.Property(pExp, info);
            var finalExp =
                Expression.Lambda<Func<Yueluo, object>>(Expression.Convert(bodyExp, typeof(object)), pExp);
            return finalExp.Compile();
        }
        private static int GetKey(MemberInfo info)
        {
            var token = info.MetadataToken;
            return token;
        }
        [Benchmark(Baseline = true)]
        public string Directly() => _func(_yueluo);
        [Benchmark]
        public string ArrayIndex() => (string) _target[_nameP.MetadataToken % _target.Length](_yueluo);
        [Benchmark]
        public string SwitchExp() => (string) _switcher(_nameP)(_yueluo);
        [Benchmark]
        public string Dic() => (string) _dic[_nameP](_yueluo);
    }
}

BenchmarkDotNet=v0.12.1, OS=Windows 10.0.19041.572 (2004/?/20H1)
Intel Xeon CPU E5-2678 v3 2.50GHz, 1 CPU, 24 logical and 12 physical cores
.NET Core SDK=5.0.100-rc.2.20479.15
  [Host]       : .NET Core 2.1.23 (CoreCLR 4.6.29321.03, CoreFX 4.6.29321.01), X64 RyuJIT
  net461       : .NET Framework 4.8 (4.8.4250.0), X64 RyuJIT
  net48        : .NET Framework 4.8 (4.8.4250.0), X64 RyuJIT
  netcoreapp21 : .NET Core 2.1.23 (CoreCLR 4.6.29321.03, CoreFX 4.6.29321.01), X64 RyuJIT
  netcoreapp31 : .NET Core 3.1.9 (CoreCLR 4.700.20.47201, CoreFX 4.700.20.47203), X64 RyuJIT
  netcoreapp5  : .NET Core 5.0.0 (CoreCLR 5.0.20.47505, CoreFX 5.0.20.47505), X64 RyuJIT