using System;
using System.Diagnostics;

namespace ConsoleApplication6
{
    struct Filter
    {
        float z1, z2;
        public float K0, K1, K2;

        public float Process(float sample)
        {
            var tmp = z1;
            z1 = sample * K0 + z1 * K1 + z2 * K2;
            z2 = tmp;
            return z1;
        }
    }

    class Box<T>
    {
        public T Value;
    }

    class Program
    {
        static void Main(string[] args)
        {
            var rnd = new Random();

            const int N = 1000000;
            var data = new float[N];

            for (int i = 0; i < N; i++)
                data[i] = (float)rnd.NextDouble();

            var filter = new Box<Filter>();
            filter.Value.K0 = (float)rnd.NextDouble();   // для исключения "случайных" оптимизаций
            filter.Value.K1 = (float)rnd.NextDouble();
            filter.Value.K2 = (float)rnd.NextDouble();

            var timer = new Stopwatch();

            // разогрев
            timer.Start();
            timer.Stop();
            Test1(filter, data);    
            Test2(filter, data);

            timer.Reset();
            timer.Start();
            Test1(filter, data);
            timer.Stop();

            Console.WriteLine("Result1: " + timer.ElapsedTicks);

            timer.Reset();
            timer.Start();
            Test2(filter, data);
            timer.Stop();

            Console.WriteLine("Result2: " + timer.ElapsedTicks);

            timer.Reset();
            timer.Start();
            Test1(filter, data);
            timer.Stop();

            Console.WriteLine("Result1: " + timer.ElapsedTicks);

            timer.Reset();
            timer.Start();
            Test2(filter, data);
            timer.Stop();

            Console.WriteLine("Result2: " + timer.ElapsedTicks);

            Console.WriteLine("Press enter...");
            Console.ReadLine();
        }

        static float Test1(Box<Filter> filterObj, float[] data)
        {
            float value = 0;

            for (int i = 0; i < data.Length; i++)
                value = filterObj.Value.Process(data[i]);

            return value;
        }

        static float Test2(Box<Filter> filterObj, float[] data)
        {
            float value = 0;
            Filter filter = filterObj.Value;

            for (int i = 0; i < data.Length; i++)
                value = filter.Process(data[i]);

            filterObj.Value = filter;
            return value;
        }
    }
}