In JavaScriptEngineSwitcher.ChakraCore improved a performance of script pre-compilation

Author: Taritsyn

global.json

@@ -1,5 +1,5 @@
 {
 	"sdk": {
-		"version": "2.1.500"
+		"version": "2.2.101"
 	}
 }

src/JavaScriptEngineSwitcher.ChakraCore/ChakraCorePrecompiledScript.cs

@@ -1,4 +1,5 @@
-using System.Text;
+using System.Runtime.InteropServices;
+using System.Text;
 
 using JavaScriptEngineSwitcher.Core;
 
@@ -12,6 +13,11 @@ namespace JavaScriptEngineSwitcher.ChakraCore
 	/// </summary>
 	internal sealed class ChakraCorePrecompiledScript : IPrecompiledScript
 	{
+		/// <summary>
+		/// Callback for finalization of external buffer
+		/// </summary>
+		private JsObjectFinalizeCallback _externalBufferFinalizeCallback;
+
 		/// <summary>
 		/// Gets a source code of the script
 		/// </summary>
@@ -68,6 +74,8 @@ public JsSerializedLoadScriptCallback LoadScriptSourceCodeCallback
 		public ChakraCorePrecompiledScript(string code, JsParseScriptAttributes parseAttributes, byte[] cachedBytes,
 			string documentName)
 		{
+			_externalBufferFinalizeCallback = Marshal.FreeHGlobal;
+
 			Code = code;
 			ParseAttributes = parseAttributes;
 			CachedBytes = cachedBytes;
@@ -94,7 +102,7 @@ private bool LoadScriptSourceCode(JsSourceContext sourceContext,
 
 			try
 			{
-				value = JsValue.CreateExternalArrayBuffer(Code, encoding);
+				value = JsValue.CreateExternalArrayBuffer(Code, encoding, _externalBufferFinalizeCallback);
 				result = true;
 			}
 			catch (OriginalException)

src/JavaScriptEngineSwitcher.ChakraCore/Helpers/EncodingHelpers.cs

@@ -1,8 +1,11 @@
-#if NET471 || NETSTANDARD || NETCOREAPP2_1
-using System;
-using System.Runtime.InteropServices;
+#if NET45 || NET471 || NETSTANDARD || NETCOREAPP2_1
+using System.Buffers;
 #endif
 using System.Text;
+#if NET40
+
+using PolyfillsForOldDotNet.System.Buffers;
+#endif
 
 namespace JavaScriptEngineSwitcher.ChakraCore.Helpers
 {
@@ -11,41 +14,34 @@ namespace JavaScriptEngineSwitcher.ChakraCore.Helpers
 	/// </summary>
 	internal static class EncodingHelpers
 	{
-#if NET471 || NETSTANDARD || NETCOREAPP2_1
-		public static unsafe string UnicodeToUtf8(string value, out int byteCount)
-#else
-		public static string UnicodeToUtf8(string value, out int byteCount)
-#endif
+		public static string UnicodeToAnsi(string value, out int byteCount)
 		{
 			if (string.IsNullOrEmpty(value))
 			{
 				byteCount = 0;
 				return value;
 			}
 
-			string result;
-#if NET471 || NETSTANDARD || NETCOREAPP2_1
-			byteCount = Encoding.UTF8.GetByteCount(value);
-			IntPtr bufferPtr = Marshal.AllocHGlobal(byteCount);
+			Encoding utf8Encoding = Encoding.UTF8;
+			Encoding ansiEncoding = Encoding.GetEncoding(0);
 
-			try
+			var byteArrayPool = ArrayPool<byte>.Shared;
+			int bufferLength = utf8Encoding.GetByteCount(value);
+			byte[] buffer = byteArrayPool.Rent(bufferLength);
+
+			unsafe
 			{
 				fixed (char* pValue = value)
+				fixed (byte* pBuffer = buffer)
 				{
-					Encoding.UTF8.GetBytes(pValue, value.Length, (byte*)bufferPtr, byteCount);
+					utf8Encoding.GetBytes(pValue, value.Length, pBuffer, bufferLength);
 				}
-
-				result = Encoding.GetEncoding(0).GetString((byte*)bufferPtr, byteCount);
 			}
-			finally
-			{
-				Marshal.FreeHGlobal(bufferPtr);
-			}
-#else
-			byte[] bytes = Encoding.UTF8.GetBytes(value);
-			byteCount = bytes.Length;
-			result = Encoding.GetEncoding(0).GetString(bytes);
-#endif
+
+			string result = ansiEncoding.GetString(buffer, 0, bufferLength);
+			byteCount = ansiEncoding.GetByteCount(result);
+
+			byteArrayPool.Return(buffer);
 
 			return result;
 		}

src/JavaScriptEngineSwitcher.ChakraCore/JavaScriptEngineSwitcher.ChakraCore.csproj

@@ -23,10 +23,7 @@ This package does not contain the native implementations of ChakraCore. Therefor
  * JavaScriptEngineSwitcher.ChakraCore.Native.osx-x64</Description>
 		<PackageIconUrl>https://raw.githubusercontent.com/Taritsyn/JavaScriptEngineSwitcher/master/Icons/JavaScriptEngineSwitcher_ChakraCore_Logo128x128.png</PackageIconUrl>
 		<PackageTags>JavaScriptEngineSwitcher;JavaScript;ECMAScript;ChakraCore</PackageTags>
-		<PackageReleaseNotes>1. ChakraCore was updated to version 1.11.3;
-2. In the `NativeMethods` class for the `netstandard` and `netcoreapp` targets was changed a calling convention from `StdCall` to `Cdecl`;
-3. Charset was explicitly specified in the `JsCreateString`, `JsCopyString` and `JsCreatePropertyId` methods of `NativeMethods` class;
-4. Added a `netcoreapp2.1` target.</PackageReleaseNotes>
+		<PackageReleaseNotes>Improved a performance of script pre-compilation.</PackageReleaseNotes>
 	</PropertyGroup>
 
 	<Import Project="../../build/common.props" />

src/JavaScriptEngineSwitcher.ChakraCore/JsRt/DefaultExternalBufferFinalizeCallback.cs

@@ -164,8 +164,7 @@ public static uint Idle()
 		public static JsValue ParseScript(string script, JsSourceContext sourceContext, string sourceUrl,
 			ref JsParseScriptAttributes parseAttributes)
 		{
-			JsValue scriptValue = CreateExternalArrayBufferFromScriptCode(script, ref parseAttributes);
-			scriptValue.AddRef();
+			JsPooledArrayBuffer scriptBuffer = CreatePooledArrayBufferFromScriptCode(script, ref parseAttributes);
 
 			JsValue sourceUrlValue = JsValue.FromString(sourceUrl);
 			sourceUrlValue.AddRef();
@@ -174,13 +173,13 @@ public static JsValue ParseScript(string script, JsSourceContext sourceContext,
 
 			try
 			{
-				JsErrorCode errorCode = NativeMethods.JsParse(scriptValue, sourceContext, sourceUrlValue,
+				JsErrorCode errorCode = NativeMethods.JsParse(scriptBuffer.Value, sourceContext, sourceUrlValue,
 					parseAttributes, out result);
 				JsErrorHelpers.ThrowIfError(errorCode);
 			}
 			finally
 			{
-				scriptValue.Release();
+				scriptBuffer.Dispose();
 				sourceUrlValue.Release();
 			}
 
@@ -225,6 +224,8 @@ public static JsValue ParseSerializedScript(string script, byte[] buffer,
 				sourceUrlValue.Release();
 			}
 
+			GC.KeepAlive(buffer);
+
 			return result;
 		}
 
@@ -243,8 +244,7 @@ public static JsValue ParseSerializedScript(string script, byte[] buffer,
 		public static JsValue RunScript(string script, JsSourceContext sourceContext, string sourceUrl,
 			ref JsParseScriptAttributes parseAttributes)
 		{
-			JsValue scriptValue = CreateExternalArrayBufferFromScriptCode(script, ref parseAttributes);
-			scriptValue.AddRef();
+			JsPooledArrayBuffer scriptBuffer = CreatePooledArrayBufferFromScriptCode(script, ref parseAttributes);
 
 			JsValue sourceUrlValue = JsValue.FromString(sourceUrl);
 			sourceUrlValue.AddRef();
@@ -253,13 +253,13 @@ public static JsValue RunScript(string script, JsSourceContext sourceContext, st
 
 			try
 			{
-				JsErrorCode errorCode = NativeMethods.JsRun(scriptValue, sourceContext, sourceUrlValue,
+				JsErrorCode errorCode = NativeMethods.JsRun(scriptBuffer.Value, sourceContext, sourceUrlValue,
 					parseAttributes, out result);
 				JsErrorHelpers.ThrowIfError(errorCode);
 			}
 			finally
 			{
-				scriptValue.Release();
+				scriptBuffer.Dispose();
 				sourceUrlValue.Release();
 			}
 
@@ -284,14 +284,14 @@ public static JsValue RunScript(string script, JsSourceContext sourceContext, st
 		public static JsValue RunSerializedScript(string script, byte[] buffer,
 			JsSerializedLoadScriptCallback scriptLoadCallback, JsSourceContext sourceContext, string sourceUrl)
 		{
-			JsValue result;
-
 			JsValue bufferValue = JsValue.CreateExternalArrayBuffer(buffer);
 			bufferValue.AddRef();
 
 			JsValue sourceUrlValue = JsValue.FromString(sourceUrl);
 			sourceUrlValue.AddRef();
 
+			JsValue result;
+
 			try
 			{
 				JsErrorCode errorCode = NativeMethods.JsRunSerialized(bufferValue, scriptLoadCallback, sourceContext,
@@ -304,6 +304,8 @@ public static JsValue RunSerializedScript(string script, byte[] buffer,
 				sourceUrlValue.Release();
 			}
 
+			GC.KeepAlive(buffer);
+
 			return result;
 		}
 
@@ -325,19 +327,17 @@ public static JsValue RunSerializedScript(string script, byte[] buffer,
 		/// <returns>The buffer to put the serialized script into</returns>
 		public static byte[] SerializeScript(string script, ref JsParseScriptAttributes parseAttributes)
 		{
-			JsValue scriptValue = CreateExternalArrayBufferFromScriptCode(script, ref parseAttributes);
-			scriptValue.AddRef();
-
+			JsPooledArrayBuffer scriptBuffer = CreatePooledArrayBufferFromScriptCode(script, ref parseAttributes);
 			JsValue bufferValue;
 
 			try
 			{
-				JsErrorCode errorCode = NativeMethods.JsSerialize(scriptValue, out bufferValue, parseAttributes);
+				JsErrorCode errorCode = NativeMethods.JsSerialize(scriptBuffer.Value, out bufferValue, parseAttributes);
 				JsErrorHelpers.ThrowIfError(errorCode);
 			}
 			finally
 			{
-				scriptValue.Release();
+				scriptBuffer.Dispose();
 			}
 
 			byte[] buffer = bufferValue.ArrayBufferBytes;
@@ -346,12 +346,12 @@ public static byte[] SerializeScript(string script, ref JsParseScriptAttributes
 		}
 
 		/// <summary>
-		/// Creates a Javascript <c>ArrayBuffer</c> object from script code
+		/// Creates a pooled Javascript <c>ArrayBuffer</c> object from script code
 		/// </summary>
 		/// <param name="script">Script code</param>
 		/// <param name="parseAttributes">Attribute mask for parsing the script</param>
-		/// <returns>The new <c>ArrayBuffer</c> object</returns>
-		private static JsValue CreateExternalArrayBufferFromScriptCode(string script,
+		/// <returns>Instance of <see cref="JsPooledArrayBuffer"/></returns>
+		private static JsPooledArrayBuffer CreatePooledArrayBufferFromScriptCode(string script,
 			ref JsParseScriptAttributes parseAttributes)
 		{
 			Encoding encoding;
@@ -366,9 +366,9 @@ private static JsValue CreateExternalArrayBufferFromScriptCode(string script,
 				encoding = Encoding.UTF8;
 			}
 
-			JsValue scriptValue = JsValue.CreateExternalArrayBuffer(script, encoding);
+			JsPooledArrayBuffer scriptBuffer = JsPooledArrayBuffer.Create(script, encoding);
 
-			return scriptValue;
+			return scriptBuffer;
 		}
 
 		/// <summary>