Remove GC, add MethodImpl, use Buffer

Directory.Build.props

@@ -31,21 +31,21 @@
 
   <!--
     https://apisof.net/
-    +===================+=======+==========+=====================+=============+=================+====================+==============+
-    | SUPPORTS          | MATHF | HASHCODE | EXTENDED_INTRINSICS | SPAN_STREAM | ENCODING_STRING | RUNTIME_INTRINSICS | CODECOVERAGE |
-    +===================+=======+==========+=====================+=============+=================+====================+==============+
-    | netcoreapp3.1     |   Y   |    Y     |         Y           |      Y      |        Y        |        Y           |      Y       |
-    | netcoreapp2.1     |   Y   |    Y     |         Y           |      Y      |        Y        |        N           |      Y       |
-    | netcoreapp2.0     |   Y   |    N     |         N           |      N      |        N        |        N           |      Y       |
-    | netstandard2.1    |   Y   |    Y     |         N           |      Y      |        Y        |        N           |      Y       |
-    | netstandard2.0    |   N   |    N     |         N           |      N      |        N        |        N           |      Y       |
-    | netstandard1.3    |   N   |    N     |         N           |      N      |        N        |        N           |      N       |
-    | net472            |   N   |    N     |         Y           |      N      |        N        |        N           |      Y       |
-    +===================+=======+==========+=====================+=============+=================+====================+==============+
+    +===================+=======+==========+=====================+=============+=================+====================+==============+=========+
+    | SUPPORTS          | MATHF | HASHCODE | EXTENDED_INTRINSICS | SPAN_STREAM | ENCODING_STRING | RUNTIME_INTRINSICS | CODECOVERAGE | HOTPATH |
+    +===================+=======+==========+=====================+=============+=================+====================+==============+=========|
+    | netcoreapp3.1     |   Y   |    Y     |         Y           |      Y      |        Y        |        Y           |      Y       |    Y    |
+    | netcoreapp2.1     |   Y   |    Y     |         Y           |      Y      |        Y        |        N           |      Y       |    N    |
+    | netcoreapp2.0     |   Y   |    N     |         N           |      N      |        N        |        N           |      Y       |    N    |
+    | netstandard2.1    |   Y   |    Y     |         N           |      Y      |        Y        |        N           |      Y       |    N    |
+    | netstandard2.0    |   N   |    N     |         N           |      N      |        N        |        N           |      Y       |    N    |
+    | netstandard1.3    |   N   |    N     |         N           |      N      |        N        |        N           |      N       |    N    |
+    | net472            |   N   |    N     |         Y           |      N      |        N        |        N           |      Y       |    N    |
+    +===================+=======+==========+=====================+=============+=================+====================+==============+=========|
     -->
 
   <PropertyGroup Condition="'$(TargetFramework)' == 'netcoreapp3.1'">
-    <DefineConstants>$(DefineConstants);SUPPORTS_MATHF;SUPPORTS_HASHCODE;SUPPORTS_EXTENDED_INTRINSICS;SUPPORTS_SPAN_STREAM;SUPPORTS_ENCODING_STRING;SUPPORTS_RUNTIME_INTRINSICS;SUPPORTS_CODECOVERAGE</DefineConstants>
+    <DefineConstants>$(DefineConstants);SUPPORTS_MATHF;SUPPORTS_HASHCODE;SUPPORTS_EXTENDED_INTRINSICS;SUPPORTS_SPAN_STREAM;SUPPORTS_ENCODING_STRING;SUPPORTS_RUNTIME_INTRINSICS;SUPPORTS_CODECOVERAGE;SUPPORTS_HOTPATH</DefineConstants>
   </PropertyGroup>
   <PropertyGroup Condition="'$(TargetFramework)' == 'netcoreapp2.1'">
     <DefineConstants>$(DefineConstants);SUPPORTS_MATHF;SUPPORTS_HASHCODE;SUPPORTS_EXTENDED_INTRINSICS;SUPPORTS_SPAN_STREAM;SUPPORTS_ENCODING_STRING;SUPPORTS_CODECOVERAGE</DefineConstants>

src/ImageSharp/Common/Helpers/InliningOptions.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Six Labors and contributors.
+// Copyright (c) Six Labors and contributors.
 // Licensed under the Apache License, Version 2.0.
 
 // Uncomment this for verbose profiler results. DO NOT PUSH TO MAIN!
@@ -13,10 +13,16 @@ namespace SixLabors.ImageSharp
     internal static class InliningOptions
     {
 #if PROFILING
+        public const MethodImplOptions HotPath = MethodImplOptions.NoInlining;
         public const MethodImplOptions ShortMethod = MethodImplOptions.NoInlining;
 #else
+#if SUPPORTS_HOTPATH
+        public const MethodImplOptions HotPath = MethodImplOptions.AggressiveOptimization;
+#else
+        public const MethodImplOptions HotPath = MethodImplOptions.AggressiveInlining;
+#endif
         public const MethodImplOptions ShortMethod = MethodImplOptions.AggressiveInlining;
 #endif
         public const MethodImplOptions ColdPath = MethodImplOptions.NoInlining;
     }
-}
+}

src/ImageSharp/Formats/Png/Zlib/Deflater.cs

@@ -288,8 +288,6 @@ namespace SixLabors.ImageSharp.Formats.Png.Zlib
                 this.engine = null;
                 this.isDisposed = true;
             }
-
-            GC.SuppressFinalize(this);
         }
     }
 }

src/ImageSharp/Formats/Png/Zlib/DeflaterEngine.cs

@@ -362,7 +362,7 @@ namespace SixLabors.ImageSharp.Formats.Png.Zlib
                     more = this.inputEnd - this.inputOff;
                 }
 
-                Array.Copy(this.inputBuf, this.inputOff, this.window, this.strstart + this.lookahead, more);
+                Buffer.BlockCopy(this.inputBuf, this.inputOff, this.window, this.strstart + this.lookahead, more);
 
                 this.inputOff += more;
                 this.lookahead += more;
@@ -397,8 +397,6 @@ namespace SixLabors.ImageSharp.Formats.Png.Zlib
 
                 this.isDisposed = true;
             }
-
-            GC.SuppressFinalize(this);
         }
 
         [MethodImpl(InliningOptions.ShortMethod)]
@@ -464,6 +462,7 @@ namespace SixLabors.ImageSharp.Formats.Png.Zlib
         /// </summary>
         /// <param name="curMatch">The current match.</param>
         /// <returns>True if a match greater than the minimum length is found</returns>
+        [MethodImpl(InliningOptions.HotPath)]
         private bool FindLongestMatch(int curMatch)
         {
             int match;

src/ImageSharp/Formats/Png/Zlib/DeflaterHuffman.cs

@@ -413,8 +413,6 @@ namespace SixLabors.ImageSharp.Formats.Png.Zlib
                 this.distTree = null;
                 this.isDisposed = true;
             }
-
-            GC.SuppressFinalize(this);
         }
 
         [MethodImpl(InliningOptions.ShortMethod)]
@@ -553,6 +551,7 @@ namespace SixLabors.ImageSharp.Formats.Png.Zlib
                 }
             }
 
+            [MethodImpl(InliningOptions.HotPath)]
             public void BuildTree()
             {
                 int numSymbols = this.elementCount;
@@ -964,8 +963,6 @@ namespace SixLabors.ImageSharp.Formats.Png.Zlib
 
                     this.isDisposed = true;
                 }
-
-                GC.SuppressFinalize(this);
             }
         }
     }

src/ImageSharp/Formats/Png/Zlib/DeflaterPendingBuffer.cs

@@ -172,8 +172,6 @@ namespace SixLabors.ImageSharp.Formats.Png.Zlib
                 this.bufferMemoryOwner = null;
                 this.isDisposed = true;
             }
-
-            GC.SuppressFinalize(this);
         }
     }
 }