Benchmarks: PixelAccessorVirtualCopy, vectorization

src/ImageSharp/Image/PixelAccessor{TColor}.cs

@@ -120,6 +120,11 @@ namespace ImageSharp
         /// </summary>
         public bool PooledMemory { get; private set; }
 
+        /// <summary>
+        /// Gets the pixel buffer array.
+        /// </summary>
+        public TColor[] PixelBuffer => this.pixelBuffer;
+
         /// <summary>
         /// Gets the pointer to the pixel buffer.
         /// </summary>

tests/ImageSharp.Benchmarks/Color/Bulk/PixelAccessorVirtualCopy.cs

@@ -0,0 +1,129 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace ImageSharp.Benchmarks.Color.Bulk
+{
+    using System.Runtime.CompilerServices;
+    using System.Runtime.InteropServices;
+
+    using BenchmarkDotNet.Attributes;
+
+    using Color = ImageSharp.Color;
+
+    /// <summary>
+    /// Benchmark to measure the effect of using virtual bulk-copy calls inside PixelAccessor methods
+    /// </summary>
+    public unsafe class PixelAccessorVirtualCopy
+    {
+        abstract class CopyExecutor
+        {
+            internal abstract void VirtualCopy(ArrayPointer<Color> destination, ArrayPointer<byte> source, int count);
+        }
+
+        class UnsafeCopyExecutor : CopyExecutor
+        {
+            [MethodImpl(MethodImplOptions.NoInlining)]
+            internal override unsafe void VirtualCopy(ArrayPointer<Color> destination, ArrayPointer<byte> source, int count)
+            {
+                Unsafe.CopyBlock((void*)destination.PointerAtOffset, (void*)source.PointerAtOffset, (uint)count*4);
+            }
+        }
+        
+        private PixelAccessor<Color> pixelAccessor;
+
+        private PixelArea<Color> area;
+
+        private CopyExecutor executor;
+        
+        [Params(64, 256)]
+        public int Width { get; set; }
+
+        public int Height { get; set; } = 256;
+        
+
+        [Setup]
+        public void Setup()
+        {
+            this.pixelAccessor = new PixelAccessor<ImageSharp.Color>(this.Width, this.Height);
+            this.area = new PixelArea<Color>(this.Width / 2, this.Height, ComponentOrder.Xyzw);
+            this.executor = new UnsafeCopyExecutor();
+        }
+
+        [Cleanup]
+        public void Cleanup()
+        {
+            this.pixelAccessor.Dispose();
+            this.area.Dispose();
+        }
+
+        [Benchmark(Baseline = true)]
+        public void CopyRawUnsafeInlined()
+        {
+            uint byteCount = (uint)this.area.Width * 4;
+
+            int targetX = this.Width / 4;
+            int targetY = 0;
+
+            for (int y = 0; y < this.Height; y++)
+            {
+                byte* source = this.area.PixelBase + (y * this.area.RowStride);
+                byte* destination = this.GetRowPointer(targetX, targetY + y);
+
+                Unsafe.CopyBlock(destination, source, byteCount);
+            }
+        }
+        
+        [Benchmark]
+        public void CopyArrayPointerUnsafeInlined()
+        {
+            uint byteCount = (uint)this.area.Width * 4;
+
+            int targetX = this.Width / 4;
+            int targetY = 0;
+
+            for (int y = 0; y < this.Height; y++)
+            {
+                ArrayPointer<byte> source = this.GetAreaRow(y);
+                ArrayPointer<Color> destination = this.GetPixelAccessorRow(targetX, targetY + y);
+                Unsafe.CopyBlock((void*)destination.PointerAtOffset, (void*)source.PointerAtOffset, byteCount);
+            }
+        }
+        
+        [Benchmark]
+        public void CopyArrayPointerUnsafeVirtual()
+        {
+            int targetX = this.Width / 4;
+            int targetY = 0;
+
+            for (int y = 0; y < this.Height; y++)
+            {
+                ArrayPointer<byte> source = this.GetAreaRow(y);
+                ArrayPointer<Color> destination = this.GetPixelAccessorRow(targetX, targetY + y);
+                this.executor.VirtualCopy(destination, source, this.area.Width);
+            }
+        }
+        
+        private byte* GetRowPointer(int x, int y)
+        {
+            return (byte*)this.pixelAccessor.DataPointer + (((y * this.pixelAccessor.Width) + x) * Unsafe.SizeOf<Color>());
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private ArrayPointer<Color> GetPixelAccessorRow(int x, int y)
+        {
+            return new ArrayPointer<ImageSharp.Color>(
+                this.pixelAccessor.PixelBuffer,
+                (void*)this.pixelAccessor.DataPointer,
+                (y * this.pixelAccessor.Width) + x
+                );
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private ArrayPointer<byte> GetAreaRow(int y)
+        {
+            return new ArrayPointer<byte>(this.area.Bytes, this.area.PixelBase, y * this.area.RowStride);
+        }
+    }
+}

tests/ImageSharp.Benchmarks/Drawing/DrawBeziers.cs

@@ -28,7 +28,7 @@ namespace ImageSharp.Benchmarks
                 {
                     graphics.InterpolationMode = InterpolationMode.Default;
                     graphics.SmoothingMode = SmoothingMode.AntiAlias;
-                    var pen = new Pen(Color.HotPink, 10);
+                    var pen = new Pen(System.Drawing.Color.HotPink, 10);
                     graphics.DrawBeziers(pen, new[] {
                         new PointF(10, 500),
                         new PointF(30, 10),

tests/ImageSharp.Benchmarks/Drawing/DrawLines.cs

@@ -28,7 +28,7 @@ namespace ImageSharp.Benchmarks
                 {
                     graphics.InterpolationMode = InterpolationMode.Default;
                     graphics.SmoothingMode = SmoothingMode.AntiAlias;
-                    var pen = new Pen(Color.HotPink, 10);
+                    var pen = new Pen(System.Drawing.Color.HotPink, 10);
                     graphics.DrawLines(pen, new[] {
                         new PointF(10, 10),
                         new PointF(550, 50),

tests/ImageSharp.Benchmarks/Drawing/DrawPolygon.cs

@@ -27,7 +27,7 @@ namespace ImageSharp.Benchmarks
                 {
                     graphics.InterpolationMode = InterpolationMode.Default;
                     graphics.SmoothingMode = SmoothingMode.AntiAlias;
-                    var pen = new Pen(Color.HotPink, 10);
+                    var pen = new Pen(System.Drawing.Color.HotPink, 10);
                     graphics.DrawPolygon(pen, new[] {
                         new PointF(10, 10),
                         new PointF(550, 50),

tests/ImageSharp.Benchmarks/Drawing/FillWithPattern.cs

@@ -25,7 +25,7 @@ namespace ImageSharp.Benchmarks
                 using (Graphics graphics = Graphics.FromImage(destination))
                 {
                     graphics.SmoothingMode = SmoothingMode.AntiAlias;
-                    var brush = new HatchBrush(HatchStyle.BackwardDiagonal, Color.HotPink);
+                    var brush = new HatchBrush(HatchStyle.BackwardDiagonal, System.Drawing.Color.HotPink);
                     graphics.FillRectangle(brush, new Rectangle(0,0, 800,800)); // can't find a way to flood fill with a brush
                 }
                 using (MemoryStream ms = new MemoryStream())

tests/ImageSharp.Benchmarks/General/Vectorization/BitwiseOrUint32.cs

@@ -0,0 +1,54 @@
+namespace ImageSharp.Benchmarks.General.Vectorization
+{
+    using System.Numerics;
+
+    using BenchmarkDotNet.Attributes;
+
+    public class BitwiseOrUInt32
+    {
+        private uint[] input;
+
+        private uint[] result;
+
+        [Params(32)]
+        public int InputSize { get; set; }
+
+        private uint testValue;
+
+        [Setup]
+        public void Setup()
+        {
+            this.input = new uint[this.InputSize];
+            this.result = new uint[this.InputSize];
+            this.testValue = 42;
+
+            for (int i = 0; i < this.InputSize; i++)
+            {
+                this.input[i] = (uint) i;
+            }
+        }
+
+        [Benchmark(Baseline = true)]
+        public void Standard()
+        {
+            uint v = this.testValue;
+            for (int i = 0; i < this.input.Length; i++)
+            {
+                this.result[i] = this.input[i] | v;
+            }
+        }
+
+        [Benchmark]
+        public void Simd()
+        {
+            Vector<uint> v = new Vector<uint>(this.testValue);
+
+            for (int i = 0; i < this.input.Length; i+=Vector<uint>.Count)
+            {
+                Vector<uint> a = new Vector<uint>(this.input, i);
+                a = Vector.BitwiseOr(a, v);
+                a.CopyTo(this.result, i);
+            }
+        }
+    }
+}

tests/ImageSharp.Benchmarks/General/Vectorization/DivFloat.cs

@@ -0,0 +1,54 @@
+namespace ImageSharp.Benchmarks.General.Vectorization
+{
+    using System.Numerics;
+
+    using BenchmarkDotNet.Attributes;
+
+    public class DivFloat
+    {
+        private float[] input;
+
+        private float[] result;
+
+        [Params(32)]
+        public int InputSize { get; set; }
+
+        private float testValue;
+
+        [Setup]
+        public void Setup()
+        {
+            this.input = new float[this.InputSize];
+            this.result = new float[this.InputSize];
+            this.testValue = 42;
+
+            for (int i = 0; i < this.InputSize; i++)
+            {
+                this.input[i] = (uint)i;
+            }
+        }
+
+        [Benchmark(Baseline = true)]
+        public void Standard()
+        {
+            float v = this.testValue;
+            for (int i = 0; i < this.input.Length; i++)
+            {
+                this.result[i] = this.input[i] / v;
+            }
+        }
+
+        [Benchmark]
+        public void Simd()
+        {
+            Vector<float> v = new Vector<float>(this.testValue);
+
+            for (int i = 0; i < this.input.Length; i += Vector<uint>.Count)
+            {
+                Vector<float> a = new Vector<float>(this.input, i);
+                a = a / v;
+                a.CopyTo(this.result, i);
+            }
+        }
+    }
+}

tests/ImageSharp.Benchmarks/General/Vectorization/DivUInt32.cs

@@ -0,0 +1,54 @@
+namespace ImageSharp.Benchmarks.General.Vectorization
+{
+    using System.Numerics;
+
+    using BenchmarkDotNet.Attributes;
+
+    public class DivUInt32
+    {
+        private uint[] input;
+
+        private uint[] result;
+
+        [Params(32)]
+        public int InputSize { get; set; }
+
+        private uint testValue;
+
+        [Setup]
+        public void Setup()
+        {
+            this.input = new uint[this.InputSize];
+            this.result = new uint[this.InputSize];
+            this.testValue = 42;
+
+            for (int i = 0; i < this.InputSize; i++)
+            {
+                this.input[i] = (uint)i;
+            }
+        }
+
+        [Benchmark(Baseline = true)]
+        public void Standard()
+        {
+            uint v = this.testValue;
+            for (int i = 0; i < this.input.Length; i++)
+            {
+                this.result[i] = this.input[i] / v;
+            }
+        }
+
+        [Benchmark]
+        public void Simd()
+        {
+            Vector<uint> v = new Vector<uint>(this.testValue);
+
+            for (int i = 0; i < this.input.Length; i += Vector<uint>.Count)
+            {
+                Vector<uint> a = new Vector<uint>(this.input, i);
+                a = a / v;
+                a.CopyTo(this.result, i);
+            }
+        }
+    }
+}

tests/ImageSharp.Benchmarks/General/Vectorization/MulFloat.cs

@@ -0,0 +1,54 @@
+namespace ImageSharp.Benchmarks.General.Vectorization
+{
+    using System.Numerics;
+
+    using BenchmarkDotNet.Attributes;
+
+    public class MulFloat
+    {
+        private float[] input;
+
+        private float[] result;
+
+        [Params(32)]
+        public int InputSize { get; set; }
+
+        private float testValue;
+
+        [Setup]
+        public void Setup()
+        {
+            this.input = new float[this.InputSize];
+            this.result = new float[this.InputSize];
+            this.testValue = 42;
+
+            for (int i = 0; i < this.InputSize; i++)
+            {
+                this.input[i] = (uint)i;
+            }
+        }
+
+        [Benchmark(Baseline = true)]
+        public void Standard()
+        {
+            float v = this.testValue;
+            for (int i = 0; i < this.input.Length; i++)
+            {
+                this.result[i] = this.input[i] * v;
+            }
+        }
+
+        [Benchmark]
+        public void Simd()
+        {
+            Vector<float> v = new Vector<float>(this.testValue);
+
+            for (int i = 0; i < this.input.Length; i += Vector<uint>.Count)
+            {
+                Vector<float> a = new Vector<float>(this.input, i);
+                a = a * v;
+                a.CopyTo(this.result, i);
+            }
+        }
+    }
+}

tests/ImageSharp.Benchmarks/General/Vectorization/MulUInt32.cs

@@ -0,0 +1,54 @@
+namespace ImageSharp.Benchmarks.General.Vectorization
+{
+    using System.Numerics;
+
+    using BenchmarkDotNet.Attributes;
+
+    public class MulUInt32
+    {
+        private uint[] input;
+
+        private uint[] result;
+
+        [Params(32)]
+        public int InputSize { get; set; }
+
+        private uint testValue;
+
+        [Setup]
+        public void Setup()
+        {
+            this.input = new uint[this.InputSize];
+            this.result = new uint[this.InputSize];
+            this.testValue = 42;
+
+            for (int i = 0; i < this.InputSize; i++)
+            {
+                this.input[i] = (uint)i;
+            }
+        }
+
+        [Benchmark(Baseline = true)]
+        public void Standard()
+        {
+            uint v = this.testValue;
+            for (int i = 0; i < this.input.Length; i++)
+            {
+                this.result[i] = this.input[i] * v;
+            }
+        }
+
+        [Benchmark]
+        public void Simd()
+        {
+            Vector<uint> v = new Vector<uint>(this.testValue);
+
+            for (int i = 0; i < this.input.Length; i += Vector<uint>.Count)
+            {
+                Vector<uint> a = new Vector<uint>(this.input, i);
+                a = a * v;
+                a.CopyTo(this.result, i);
+            }
+        }
+    }
+}

tests/ImageSharp.Benchmarks/General/Vectorization/ReinterpretUInt32AsFloat.cs

@@ -0,0 +1,62 @@
+namespace ImageSharp.Benchmarks.General.Vectorization
+{
+    using System.Numerics;
+    using System.Runtime.InteropServices;
+
+    using BenchmarkDotNet.Attributes;
+
+    public class ReinterpretUInt32AsFloat
+    {
+        private uint[] input;
+
+        private float[] result;
+
+        [Params(32)]
+        public int InputSize { get; set; }
+
+        [StructLayout(LayoutKind.Explicit)]
+        struct UIntFloatUnion
+        {
+            [FieldOffset(0)]
+            public float f;
+
+            [FieldOffset(0)]
+            public uint i;
+        }
+
+
+        [Setup]
+        public void Setup()
+        {
+            this.input = new uint[this.InputSize];
+            this.result = new float[this.InputSize];
+            
+            for (int i = 0; i < this.InputSize; i++)
+            {
+                this.input[i] = (uint)i;
+            }
+        }
+
+        [Benchmark(Baseline = true)]
+        public void Standard()
+        {
+            UIntFloatUnion u = default(UIntFloatUnion);
+            for (int i = 0; i < this.input.Length; i++)
+            {
+                u.i = this.input[i];
+                this.result[i] = u.f;
+            }
+        }
+
+        [Benchmark]
+        public void Simd()
+        {
+            for (int i = 0; i < this.input.Length; i += Vector<uint>.Count)
+            {
+                Vector<uint> a = new Vector<uint>(this.input, i);
+                Vector<float> b = Vector.AsVectorSingle(a);
+                b.CopyTo(this.result, i);
+            }
+        }
+    }
+}

tests/ImageSharp.Sandbox46/ImageSharp.Sandbox46.csproj

@@ -109,6 +109,10 @@
       <HintPath>..\..\packages\System.Reflection.Metadata.1.3.0\lib\portable-net45+win8\System.Reflection.Metadata.dll</HintPath>
       <Private>True</Private>
     </Reference>
+    <Reference Include="System.Runtime.CompilerServices.Unsafe, Version=4.0.2.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\System.Runtime.CompilerServices.Unsafe.4.3.0\lib\netstandard1.0\System.Runtime.CompilerServices.Unsafe.dll</HintPath>
+      <Private>True</Private>
+    </Reference>
     <Reference Include="System.Security.Cryptography.Algorithms, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
       <HintPath>..\..\packages\System.Security.Cryptography.Algorithms.4.2.0\lib\net461\System.Security.Cryptography.Algorithms.dll</HintPath>
       <Private>True</Private>
@@ -202,6 +206,9 @@
     </Reference>
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="..\ImageSharp.Benchmarks\Color\Bulk\PixelAccessorVirtualCopy.cs">
+      <Link>Benchmarks\PixelAccessorVirtualCopy.cs</Link>
+    </Compile>
     <Compile Include="..\ImageSharp.Tests\Drawing\PolygonTests.cs">
       <Link>Tests\Drawing\PolygonTests.cs</Link>
     </Compile>
@@ -327,9 +334,7 @@
   <ItemGroup>
     <Service Include="{82A7F48D-3B50-4B1E-B82E-3ADA8210C358}" />
   </ItemGroup>
-  <ItemGroup>
-    <Folder Include="Benchmarks\" />
-  </ItemGroup>
+  <ItemGroup />
   <ItemGroup>
     <Analyzer Include="..\..\packages\Microsoft.CodeAnalysis.Analyzers.1.1.0\analyzers\dotnet\cs\Microsoft.CodeAnalysis.Analyzers.dll" />
     <Analyzer Include="..\..\packages\Microsoft.CodeAnalysis.Analyzers.1.1.0\analyzers\dotnet\cs\Microsoft.CodeAnalysis.CSharp.Analyzers.dll" />

tests/ImageSharp.Sandbox46/Program.cs

@@ -8,6 +8,7 @@ namespace ImageSharp.Sandbox46
     using System;
     using System.Runtime.DesignerServices;
 
+    using ImageSharp.Benchmarks.Color.Bulk;
     using ImageSharp.Tests;
 
     using Xunit.Abstractions;
@@ -36,7 +37,23 @@ namespace ImageSharp.Sandbox46
         /// </param>
         public static void Main(string[] args)
         {
-            RunDecodeJpegProfilingTests();
+            //RunDecodeJpegProfilingTests();
+            TestPixelAccessorCopyFromXyzw();
+            Console.ReadLine();
+        }
+
+        private static void TestPixelAccessorCopyFromXyzw()
+        {
+            PixelAccessorVirtualCopy benchmark = new PixelAccessorVirtualCopy();
+            benchmark.Width = 64;
+            benchmark.Setup();
+
+            benchmark.CopyRawUnsafeInlined();
+            benchmark.CopyArrayPointerUnsafe();
+            benchmark.CopyArrayPointerVirtualUnsafe();
+            benchmark.CopyArrayPointerVirtualMarshal();
+            
+            benchmark.Cleanup();
         }
 
         private static void RunDecodeJpegProfilingTests()

tests/ImageSharp.Sandbox46/app.config

@@ -10,6 +10,10 @@
         <assemblyIdentity name="System.Collections.Immutable" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
         <bindingRedirect oldVersion="0.0.0.0-1.2.0.0" newVersion="1.2.0.0" />
       </dependentAssembly>
+      <dependentAssembly>
+        <assemblyIdentity name="System.Runtime.CompilerServices.Unsafe" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
+        <bindingRedirect oldVersion="0.0.0.0-4.0.2.0" newVersion="4.0.2.0" />
+      </dependentAssembly>
     </assemblyBinding>
   </runtime>
 </configuration>

tests/ImageSharp.Sandbox46/packages.config

@@ -29,6 +29,7 @@
   <package id="System.Reflection.Primitives" version="4.0.1" targetFramework="net461" />
   <package id="System.Resources.ResourceManager" version="4.0.1" targetFramework="net461" />
   <package id="System.Runtime" version="4.1.0" targetFramework="net461" />
+  <package id="System.Runtime.CompilerServices.Unsafe" version="4.3.0" targetFramework="net461" />
   <package id="System.Runtime.Extensions" version="4.1.0" targetFramework="net461" />
   <package id="System.Runtime.Handles" version="4.0.1" targetFramework="net461" />
   <package id="System.Runtime.InteropServices" version="4.1.0" targetFramework="net461" />