ExpressionBenchmark.cs

using System;
using System.Linq.Expressions;

using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Configs;
using BenchmarkDotNet.Diagnosers;
using BenchmarkDotNet.Exporters;
using BenchmarkDotNet.Jobs;
using BenchmarkDotNet.Running;

public static class Program
{
    public static void Main(string[] args)
    {
        BenchmarkRunner.Run<Benchmark>();
    }
}

public class BenchmarkConfig : ManualConfig
{
    public BenchmarkConfig()
    {
        AddExporter(MarkdownExporter.Default, MarkdownExporter.GitHub);
        AddDiagnoser(MemoryDiagnoser.Default);
        AddJob(Job.LongRun);
    }
}

public class Data
{
    public string Value { get; set; }
}

[Config(typeof(BenchmarkConfig))]
public class Benchmark
{
    private readonly Data data = new Data();

    private Func<Data, string> getter1;

    private Func<Data, string> getter2;

    [GlobalSetup]
    public void Setup()
    {
        getter1 = x => x.Value;
        getter2 = ToFunc<Data, string>(x => x.Value);
    }

    private static Func<T, TRet> ToFunc<T, TRet>(Expression<Func<T, TRet>> expression)
    {
        return expression.Compile();
    }

    [Benchmark]
    public string Getter1() => getter1(data);

    [Benchmark]
    public string Getter2() => getter2(data);
}

Result.md

Method	Mean	Error	StdDev	Median	Gen 0	Gen 1	Gen 2	Allocated
Getter1	1.2362 ns	0.0549 ns	0.2771 ns	1.3100 ns	-	-	-	-
Getter2	0.8595 ns	0.0372 ns	0.1903 ns	0.9295 ns	-	-	-	-