start working on preloading generic code paths for JIT

encompass-cs/UberEngine.cs

@@ -0,0 +1,35 @@
+using System;
+using System.Reflection;
+
+namespace Encompass
+{
+    internal class UberEngine : Engine
+    {
+        public override void Update(double dt)
+        {
+            foreach (var type in readTypes)
+            {
+                var instanceParam = new object[] { Activator.CreateInstance(type) };
+
+                CallMethodByName(type, "ReadComponent", null);
+                CallMethodByName(type, "ReadComponentIncludingEntity", null);
+                CallMethodByName(type, "ReadComponents", null);
+                CallMethodByName(type, "ReadComponentsIncludingEntity", null);
+                CallMethodByName(type, "GetComponent", null);
+                CallMethodByName(type, "SetComponent", instanceParam);
+                CallMethodByName(type, "HasComponent", null);
+                CallMethodByName(type, "SomeComponent", null);
+                CallMethodByName(type, "RemoveComponent", null);
+                CallMethodByName(type, "DestroyWith", null);
+                CallMethodByName(type, "DestroyAllWith", null);
+            }
+        }
+
+        private void CallMethodByName(Type type, string methodName, object[] parameters)
+        {
+            var readComponentMethod = typeof(WorldBuilder).GetMethod(methodName, BindingFlags.NonPublic | BindingFlags.Instance);
+            var genericReadComponentMethod = readComponentMethod.MakeGenericMethod(type);
+            genericReadComponentMethod.Invoke(this, parameters);
+        }
+    }
+}

encompass-cs/WorldBuilder.cs

@@ -149,6 +149,9 @@ namespace Encompass
                 typeToReaders[receiveType].Add(engine);
             }
 
+            // System.Runtime.CompilerServices.RuntimeHelpers.PrepareMethod(typeof(TEngine).GetRuntimeMethod("Update", new Type[] { typeof(double) }).MethodHandle);
+            // typeof(TEngine).GetMethod("Update", new Type[] { typeof(double) }).MethodHandle.GetFunctionPointer();
+
             return engine;
         }
 
@@ -367,5 +370,21 @@ namespace Encompass
 
             return world;
         }
+
+        /// <summary>
+        /// This is necessary because Encompass heavily uses generic methods with value types,
+        /// so the first time any code path runs the JIT gets smashed. This method warms up the runtime.
+        /// </summary>
+        private void PreloadJIT(IEnumerable<Type> componentTypes)
+        {
+            var dummyWorldBuilder = new WorldBuilder();
+
+            dummyWorldBuilder.AddEngine(new UberEngine());
+
+            var dummyWorld = dummyWorldBuilder.Build();
+
+            dummyWorld.Update(1);
+            dummyWorld.Draw();
+        }
     }
 }