Compilier optimization

Optimization.cs

using System;
using System.Diagnostics;

namespace Optimization
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var instance = new Program();
            int loop = 1000 * 1000 * 1000;
            instance.Idle(loop);
            instance.Direct(loop);
            instance.Delegate(loop);
        }

        public void TargetMethod()
        {
        }

        private void Idle(int loop)
        {
            Stopwatch stopwatch = Stopwatch.StartNew();
            for (int i = 0; i < loop; i++)
            {
            }
            stopwatch.Stop();
            Console.WriteLine(stopwatch.Elapsed);
        }

        private void Direct(int loop)
        {
            Stopwatch stopwatch = Stopwatch.StartNew();
            for (int i = 0; i < loop; i++)
            {
                TargetMethod();
            }
            stopwatch.Stop();
            Console.WriteLine(stopwatch.Elapsed);
        }

        private void Delegate(int loop)
        {
            Action del = TargetMethod;
            Stopwatch stopwatch = Stopwatch.StartNew();
            for (int i = 0; i < loop; i++)
            {
                del();
            }
            stopwatch.Stop();
            Console.WriteLine(stopwatch.Elapsed);
        }
    }
}