The article demonstrates the advantages of loop unrolling by iterating over multiple items per cycle while adjusting the loop counter accordingly. Learning Objectives The problem with iterating using traditional loops
Advantages with loop unrolling Prerequisites for Developers Basic understanding of C# programming language.


Familiar with for loops Getting Started The problem with iterating using traditional loops Most developers will iterate over array elements and perform a mathematical operation as shown in the following code snippet. for (int i = 0; i < array.Length; i++)
    {
        array[i] = i * 2;
    } Although the above code snippet is quite clean and straightforward, it incurs a cost due to the loop control structure. Advantages with loop unrolling Please find below the refactored version of the previous code snippet int len = array.Length;
    for (int i = 0; i < len; i += 4)
    {
        array[i] = i * 2;
        if (i + 1 < len) array[i + 1] = (i + 1) * 2;
        if (i + 2 < len) array[i + 2] = (i + 2) * 2;
        if (i + 3 < len) array[i + 3] = (i + 3) * 2;
    } With refactored code, now we have reduced the loop frequency to 4 which leads to faster execution. In addition to that, it will: Reduce loop overheads which in turn decreases any conditional checks inside the loops.
Increase performance as it enhances the execution speed Complete Code Create another class named LoopUnrolling and add the following code snippet public static class LoopUnrolling
    {
        public static void BadWay() {
            const int size = 1024;
            int[] numbers = new int[size];
    
            // Traditional loop
            var watch = System.Diagnostics.Stopwatch.StartNew();
            for (int i = 0; i < numbers.Length; i++)
            {
                numbers[i] = i * 2;
            }
            watch.Stop();
            Console.WriteLine($"Traditional loop time: {watch.ElapsedTicks} ticks");
    
        }
        public static void GoodWay()
        {
            const int size = 1024;
            int[] numbers = new int[size];
            int len = numbers.Length;
            var watch = System.Diagnostics.Stopwatch.StartNew();
            for (int i = 0; i < len; i += 4)
            {
                numbers[i] = i * 2;
                if (i + 1 < len) numbers[i + 1] = (i + 1) * 2;
                if (i + 2 < len) numbers[i + 2] = (i + 2) * 2;
                if (i + 3 < len) numbers[i + 3] = (i + 3) * 2;
            }
            watch.Stop();
            Console.WriteLine($"Unrolled loop time: {watch.ElapsedTicks} ticks");
        }
    } Execute from the main method as follows #region Day 26: Loop Unrolling
    static string ExecuteDay26()
    {
        LoopUnrolling.BadWay();
        LoopUnrolling.GoodWay();
    
        return "Executed Day 26 successfully..!!";
    }
    
    #endregion Console Output Traditional loop time: 20 ticks
    Unrolled loop time: 12 ticks As the output demonstrates loop unrolling took much less time than the traditional loop approach. Complete Code here: GitHub — ssukhpinder/30DayChallenge.Net Thank you for being a part of the C# community! Before you leave: Follow us: Youtube | X | LinkedIn | Dev.to
Visit our other platforms: GitHub
More content at C# Programming The article demonstrates the advantages of loop unrolling by iterating over multiple items per cycle while adjusting the loop counter accordingly. Learning Objectives The problem with iterating using traditional loops Advantages with loop unrolling The problem with iterating using traditional loops Advantages with loop unrolling Prerequisites for Developers Basic understanding of C# programming language. Familiar with for loops Basic understanding of C# programming language. Basic understanding of C# programming language. Familiar with for loops Familiar with for loops Getting Started The problem with iterating using traditional loops Most developers will iterate over array elements and perform a mathematical operation as shown in the following code snippet. for (int i = 0; i < array.Length; i++)
    {
        array[i] = i * 2;
    } for (int i = 0; i < array.Length; i++)
    {
        array[i] = i * 2;
    } Although the above code snippet is quite clean and straightforward, it incurs a cost due to the loop control structure. Advantages with loop unrolling Please find below the refactored version of the previous code snippet int len = array.Length;
    for (int i = 0; i < len; i += 4)
    {
        array[i] = i * 2;
        if (i + 1 < len) array[i + 1] = (i + 1) * 2;
        if (i + 2 < len) array[i + 2] = (i + 2) * 2;
        if (i + 3 < len) array[i + 3] = (i + 3) * 2;
    } int len = array.Length;
    for (int i = 0; i < len; i += 4)
    {
        array[i] = i * 2;
        if (i + 1 < len) array[i + 1] = (i + 1) * 2;
        if (i + 2 < len) array[i + 2] = (i + 2) * 2;
        if (i + 3 < len) array[i + 3] = (i + 3) * 2;
    } With refactored code, now we have reduced the loop frequency to 4 which leads to faster execution. In addition to that, it will: Reduce loop overheads which in turn decreases any conditional checks inside the loops. Increase performance as it enhances the execution speed Reduce loop overheads which in turn decreases any conditional checks inside the loops. Increase performance as it enhances the execution speed Complete Code Create another class named LoopUnrolling and add the following code snippet public static class LoopUnrolling
    {
        public static void BadWay() {
            const int size = 1024;
            int[] numbers = new int[size];
    
            // Traditional loop
            var watch = System.Diagnostics.Stopwatch.StartNew();
            for (int i = 0; i < numbers.Length; i++)
            {
                numbers[i] = i * 2;
            }
            watch.Stop();
            Console.WriteLine($"Traditional loop time: {watch.ElapsedTicks} ticks");
    
        }
        public static void GoodWay()
        {
            const int size = 1024;
            int[] numbers = new int[size];
            int len = numbers.Length;
            var watch = System.Diagnostics.Stopwatch.StartNew();
            for (int i = 0; i < len; i += 4)
            {
                numbers[i] = i * 2;
                if (i + 1 < len) numbers[i + 1] = (i + 1) * 2;
                if (i + 2 < len) numbers[i + 2] = (i + 2) * 2;
                if (i + 3 < len) numbers[i + 3] = (i + 3) * 2;
            }
            watch.Stop();
            Console.WriteLine($"Unrolled loop time: {watch.ElapsedTicks} ticks");
        }
    } public static class LoopUnrolling
    {
        public static void BadWay() {
            const int size = 1024;
            int[] numbers = new int[size];
    
            // Traditional loop
            var watch = System.Diagnostics.Stopwatch.StartNew();
            for (int i = 0; i < numbers.Length; i++)
            {
                numbers[i] = i * 2;
            }
            watch.Stop();
            Console.WriteLine($"Traditional loop time: {watch.ElapsedTicks} ticks");
    
        }
        public static void GoodWay()
        {
            const int size = 1024;
            int[] numbers = new int[size];
            int len = numbers.Length;
            var watch = System.Diagnostics.Stopwatch.StartNew();
            for (int i = 0; i < len; i += 4)
            {
                numbers[i] = i * 2;
                if (i + 1 < len) numbers[i + 1] = (i + 1) * 2;
                if (i + 2 < len) numbers[i + 2] = (i + 2) * 2;
                if (i + 3 < len) numbers[i + 3] = (i + 3) * 2;
            }
            watch.Stop();
            Console.WriteLine($"Unrolled loop time: {watch.ElapsedTicks} ticks");
        }
    } Execute from the main method as follows #region Day 26: Loop Unrolling
    static string ExecuteDay26()
    {
        LoopUnrolling.BadWay();
        LoopUnrolling.GoodWay();
    
        return "Executed Day 26 successfully..!!";
    }
    
    #endregion #region Day 26: Loop Unrolling
    static string ExecuteDay26()
    {
        LoopUnrolling.BadWay();
        LoopUnrolling.GoodWay();
    
        return "Executed Day 26 successfully..!!";
    }
    
    #endregion Console Output Traditional loop time: 20 ticks
    Unrolled loop time: 12 ticks Traditional loop time: 20 ticks
    Unrolled loop time: 12 ticks As the output demonstrates loop unrolling took much less time than the traditional loop approach. Complete Code here: GitHub — ssukhpinder/30DayChallenge.Net Complete Code here: GitHub — ssukhpinder/30DayChallenge.Net GitHub — ssukhpinder/30DayChallenge.Net Thank you for being a part of the C# community! Before you leave: Follow us: Youtube | X | LinkedIn | Dev.to Visit our other platforms: GitHub More content at C# Programming Youtube X LinkedIn Dev.to GitHub C# Programming

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30-Day .NET Challenge - Day 26: Loop Unrolling

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