Implement runtime JIT capability detection.

Author: yfakariya

src/MsgPack/Serialization/EmittingSerializers/SerializationMethodGeneratorManager.cs

@@ -94,7 +94,7 @@ public static SerializationMethodGeneratorManager Get( SerializationMethodGenera
 
 #if !SILVERLIGHT
 
-		private static SerializationMethodGeneratorManager _canCollect = new SerializationMethodGeneratorManager( false, true, null );
+		private static SerializationMethodGeneratorManager _canCollect = Create( false, true, null );
 
 		/// <summary>
 		///		Get the singleton instance for can-collect mode.
@@ -105,7 +105,7 @@ public static SerializationMethodGeneratorManager CanCollect
 		}
 
 #if !NETSTANDARD1_1 && !NETSTANDARD1_3
-		private static SerializationMethodGeneratorManager _canDump = new SerializationMethodGeneratorManager( true, false, null );
+		private static SerializationMethodGeneratorManager _canDump = Create( true, false, null );
 
 		/// <summary>
 		///		Get the singleton instance for can-dump mode.
@@ -118,7 +118,7 @@ public static SerializationMethodGeneratorManager CanDump
 #endif // !NETSTANDARD1_1 && !NETSTANDARD1_3
 #endif // !SILVERLIGHT
 
-		private static SerializationMethodGeneratorManager _fast = new SerializationMethodGeneratorManager( false, false, null );
+		private static SerializationMethodGeneratorManager _fast = Create( false, false, null );
 
 		/// <summary>
 		///		Get the singleton instance for fast mode.
@@ -128,15 +128,27 @@ public static SerializationMethodGeneratorManager Fast
 			get { return _fast; }
 		}
 
+		private static SerializationMethodGeneratorManager Create( bool isDebuggable, bool isCollectable, AssemblyBuilder assemblyBuilder )
+		{
+			try
+			{
+				return new SerializationMethodGeneratorManager( isDebuggable, isCollectable, assemblyBuilder );
+			}
+			catch ( PlatformNotSupportedException )
+			{
+				return null;
+			}
+		}
+
 		internal static void Refresh()
 		{
 #if !SILVERLIGHT
-			_canCollect = new SerializationMethodGeneratorManager( false, true, null );
+			_canCollect = Create( false, true, null );
 #if !NETSTANDARD1_1 && !NETSTANDARD1_3
-			_canDump = new SerializationMethodGeneratorManager( true, false, null );
+			_canDump = Create( true, false, null );
 #endif // !NETSTANDARD1_1 && !NETSTANDARD1_3
 #endif // !SILVERLIGHT
-			_fast = new SerializationMethodGeneratorManager( false, false, null );
+			_fast = Create( false, false, null );
 		}
 
 		// ReSharper disable once PrivateFieldCanBeConvertedToLocalVariable

src/MsgPack/Serialization/SerializationContext.cs

@@ -655,23 +655,23 @@ public MessagePackSerializer<T> GetSerializer<T>( object providerParameter )
 
 						if ( serializer == null )
 						{
-#if !AOT
-							if ( this._serializerGeneratorOptions.DisableRuntimeCodeGeneration )
+#if !UNITY
+							if ( !this._serializerGeneratorOptions.CanRuntimeCodeGeneration )
 							{
-#endif // AOT
+#endif // !UNITY
 								// On debugging, or AOT only envs, use reflection based aproach.
 								serializer =
 									this.GetSerializerWithoutGeneration<T>( schema )
 									?? this.OnResolveSerializer<T>( schema )
 									?? MessagePackSerializer.CreateReflectionInternal<T>( this, this.EnsureConcreteTypeRegistered( typeof( T ) ), schema );
-#if !AOT
+#if !UNITY
 							}
 							else
 							{
 								// This thread creating new type serializer.
 								serializer = this.OnResolveSerializer<T>( schema ) ?? MessagePackSerializer.CreateInternal<T>( this, schema );
 							}
-#endif // !AOT
+#endif // !UNITY
 						}
 					}
 					else

src/MsgPack/Serialization/SerializerOptions.cs

@@ -1,4 +1,4 @@
-#region -- License Terms --
+#region -- License Terms --
 //
 // MessagePack for CLI
 //
@@ -24,12 +24,20 @@
 #endif
 
 using System;
-using System.Threading;
 #if CORE_CLR || UNITY || NETSTANDARD1_1
 using Contract = MsgPack.MPContract;
 #else
 using System.Diagnostics.Contracts;
 #endif // CORE_CLR || UNITY || NETSTANDARD1_1
+#if NETSTANDARD1_3 || NETSTANDARD2_0
+using System.Reflection;
+using System.Reflection.Emit;
+#endif // NETSTANDARD1_3 || NETSTANDARD2_0
+using System.Runtime.CompilerServices;
+using System.Threading;
+#if NETSTANDARD1_3 || NETSTANDARD2_0
+using MsgPack.Serialization.EmittingSerializers;
+#endif // NETSTANDARD1_3 || NETSTANDARD2_0
 
 namespace MsgPack.Serialization
 {
@@ -59,7 +67,7 @@ internal EmitterFlavor EmitterFlavor
 			set { Volatile.Write( ref this._emitterFlavor, ( int )value ); }
 		}
 
-#if !AOT
+#if !UNITY
 
 		private int _generatorOption;
 
@@ -135,7 +143,45 @@ public bool DisableRuntimeCodeGeneration
 #endif // !FEATURE_CONCURRENT
 			}
 		}
-#endif // !AOT
+
+		private static bool CanEmit = DetermineCanEmit();
+
+		[MethodImpl( MethodImplOptions.NoInlining )]
+		private static bool DetermineCanEmit()
+		{
+#if NETSTANDARD1_3 || NETSTANDARD2_0
+			try
+			{
+				return DetermineCanEmitCore();
+			}
+			catch
+			{
+				return false;
+			}
+#elif NETFX_CORE || UNITY
+			return false;
+#else
+			// Desktop etc.
+			return true;
+#endif
+		}
+
+#if NETSTANDARD1_3 || NETSTANDARD2_0
+
+		[MethodImpl( MethodImplOptions.NoInlining )]
+		private static bool DetermineCanEmitCore()
+		{
+			return SerializationMethodGeneratorManager.Fast != null;
+		}
+
+#endif // NETSTANDARD1_3 || NETSTANDARD2_0
+
+		internal bool CanRuntimeCodeGeneration
+		{
+			get { return CanEmit && !this.DisableRuntimeCodeGeneration; }
+		}
+
+#endif // !UNITY
 
 #if !FEATURE_CONCURRENT
 		private volatile bool _isNonPublicAccessDisabled;