perf: replace isValueType with faster alternative (#1617)

According to vis benchmark here MirrorNetworking/Mirror#1614 (comment) isValueType is an expensive operation. This microoptimization replaces isValueType for a faster (not so readable) alternative
MirageNet · Mar 28, 2020 · 61163ca · 61163ca
1 parent 166b8c9
commit 61163ca
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Showing 2 changed files with 5 additions and 3 deletions.
diff --git a/Assets/Mirror/Runtime/MessagePacker.cs b/Assets/Mirror/Runtime/MessagePacker.cs
@@ -39,7 +39,7 @@ public static int GetId(Type type)
             // this works because value types cannot be derived
             // if it is a reference type (for example IMessageBase),
             // ask the message for the real type
-            int msgType = GetId(typeof(T).IsValueType ? typeof(T) : message.GetType());
+            int msgType = GetId(default(T) != null ? typeof(T) : message.GetType());
             writer.WriteUInt16((ushort)msgType);
 
             // serialize message into writer
@@ -126,7 +126,9 @@ public static bool UnpackMessage(NetworkReader messageReader, out int msgType)
                     return;
                 }
 
-                message = typeof(T).IsValueType ? default(T) : new T();
+                // if it is a value type, just use defult(T)
+                // otherwise allocate a new instance
+                message = default(T) != null ? default(T) : new T();
                 message.Deserialize(reader);
             }
             catch (Exception exception)

diff --git a/Assets/Mirror/Runtime/NetworkConnection.cs b/Assets/Mirror/Runtime/NetworkConnection.cs
@@ -239,7 +239,7 @@ internal bool InvokeHandler(int msgType, NetworkReader reader, int channelId)
                 // this works because value types cannot be derived
                 // if it is a reference type (for example IMessageBase),
                 // ask the message for the real type
-                int msgType = MessagePacker.GetId(typeof(T).IsValueType ? typeof(T) : msg.GetType());
+                int msgType = MessagePacker.GetId(default(T) != null ? typeof(T) : msg.GetType());
 
                 MessagePacker.Pack(msg, writer);
                 ArraySegment<byte> segment = writer.ToArraySegment();