Move the MakeOp to OpCodeTable class, for reduce the use of ConcurrentDictionary (#996)

ARMeilleure/Decoders/Decoder.cs

@@ -3,9 +3,7 @@ using ARMeilleure.Instructions;
 using ARMeilleure.Memory;
 using ARMeilleure.State;
 using System;
-using System.Collections.Concurrent;
 using System.Collections.Generic;
-using System.Reflection.Emit;
 
 namespace ARMeilleure.Decoders
 {
@@ -19,15 +17,6 @@ namespace ARMeilleure.Decoders
         // For lower code quality translation, we set a lower limit since we're blocking execution.
         private const int MaxInstsPerFunctionLowCq = 500;
 
-        private delegate object MakeOp(InstDescriptor inst, ulong address, int opCode);
-
-        private static ConcurrentDictionary<Type, MakeOp> _opActivators;
-
-        static Decoder()
-        {
-            _opActivators = new ConcurrentDictionary<Type, MakeOp>();
-        }
-
         public static Block[] DecodeBasicBlock(MemoryManager memory, ulong address, ExecutionMode mode)
         {
             Block block = new Block(address);
@@ -319,56 +308,32 @@ namespace ARMeilleure.Decoders
 
             InstDescriptor inst;
 
-            Type type;
+            OpCodeTable.MakeOp makeOp;
 
             if (mode == ExecutionMode.Aarch64)
             {
-                (inst, type) = OpCodeTable.GetInstA64(opCode);
+                (inst, makeOp) = OpCodeTable.GetInstA64(opCode);
             }
             else
             {
                 if (mode == ExecutionMode.Aarch32Arm)
                 {
-                    (inst, type) = OpCodeTable.GetInstA32(opCode);
+                    (inst, makeOp) = OpCodeTable.GetInstA32(opCode);
                 }
                 else /* if (mode == ExecutionMode.Aarch32Thumb) */
                 {
-                    (inst, type) = OpCodeTable.GetInstT32(opCode);
+                    (inst, makeOp) = OpCodeTable.GetInstT32(opCode);
                 }
             }
 
-            if (type != null)
+            if (makeOp != null)
             {
-                return MakeOpCode(inst, type, address, opCode);
+                return (OpCode)makeOp(inst, address, opCode);
             }
             else
             {
                 return new OpCode(inst, address, opCode);
             }
         }
-
-        private static OpCode MakeOpCode(InstDescriptor inst, Type type, ulong address, int opCode)
-        {
-            MakeOp createInstance = _opActivators.GetOrAdd(type, CacheOpActivator);
-
-            return (OpCode)createInstance(inst, address, opCode);
-        }
-
-        private static MakeOp CacheOpActivator(Type type)
-        {
-            Type[] argTypes = new Type[] { typeof(InstDescriptor), typeof(ulong), typeof(int) };
-
-            DynamicMethod mthd = new DynamicMethod($"Make{type.Name}", type, argTypes);
-
-            ILGenerator generator = mthd.GetILGenerator();
-
-            generator.Emit(OpCodes.Ldarg_0);
-            generator.Emit(OpCodes.Ldarg_1);
-            generator.Emit(OpCodes.Ldarg_2);
-            generator.Emit(OpCodes.Newobj, type.GetConstructor(argTypes));
-            generator.Emit(OpCodes.Ret);
-
-            return (MakeOp)mthd.CreateDelegate(typeof(MakeOp));
-        }
     }
 }

ARMeilleure/Decoders/OpCodeTable.cs

@@ -2,11 +2,14 @@ using ARMeilleure.Instructions;
 using ARMeilleure.State;
 using System;
 using System.Collections.Generic;
+using System.Reflection.Emit;
 
 namespace ARMeilleure.Decoders
 {
     static class OpCodeTable
     {
+        public delegate object MakeOp(InstDescriptor inst, ulong address, int opCode);
+
         private const int FastLookupSize = 0x1000;
 
         private struct InstInfo
@@ -18,12 +21,32 @@ namespace ARMeilleure.Decoders
 
             public Type Type { get; }
 
+            public MakeOp MakeOp { get; }
+
             public InstInfo(int mask, int value, InstDescriptor inst, Type type)
             {
                 Mask  = mask;
                 Value = value;
                 Inst  = inst;
                 Type  = type;
+                MakeOp = CacheOpActivator(type);
+            }
+
+            private static MakeOp CacheOpActivator(Type type)
+            {
+                Type[] argTypes = new Type[] { typeof(InstDescriptor), typeof(ulong), typeof(int) };
+
+                DynamicMethod mthd = new DynamicMethod($"Make{type.Name}", type, argTypes);
+
+                ILGenerator generator = mthd.GetILGenerator();
+
+                generator.Emit(OpCodes.Ldarg_0);
+                generator.Emit(OpCodes.Ldarg_1);
+                generator.Emit(OpCodes.Ldarg_2);
+                generator.Emit(OpCodes.Newobj, type.GetConstructor(argTypes));
+                generator.Emit(OpCodes.Ret);
+
+                return (MakeOp)mthd.CreateDelegate(typeof(MakeOp));
             }
         }
 
@@ -1034,32 +1057,32 @@ namespace ARMeilleure.Decoders
             }
         }
 
-        public static (InstDescriptor inst, Type type) GetInstA32(int opCode)
+        public static (InstDescriptor inst, MakeOp makeOp) GetInstA32(int opCode)
         {
             return GetInstFromList(_instA32FastLookup[ToFastLookupIndex(opCode)], opCode);
         }
 
-        public static (InstDescriptor inst, Type type) GetInstT32(int opCode)
+        public static (InstDescriptor inst, MakeOp makeOp) GetInstT32(int opCode)
         {
             return GetInstFromList(_instT32FastLookup[ToFastLookupIndex(opCode)], opCode);
         }
 
-        public static (InstDescriptor inst, Type type) GetInstA64(int opCode)
+        public static (InstDescriptor inst, MakeOp makeOp) GetInstA64(int opCode)
         {
             return GetInstFromList(_instA64FastLookup[ToFastLookupIndex(opCode)], opCode);
         }
 
-        private static (InstDescriptor inst, Type type) GetInstFromList(InstInfo[] insts, int opCode)
+        private static (InstDescriptor inst, MakeOp makeOp) GetInstFromList(InstInfo[] insts, int opCode)
         {
             foreach (InstInfo info in insts)
             {
                 if ((opCode & info.Mask) == info.Value)
                 {
-                    return (info.Inst, info.Type);
+                    return (info.Inst, info.MakeOp);
                 }
             }
 
-            return (new InstDescriptor(InstName.Und, InstEmit.Und), typeof(OpCode));
+            return (new InstDescriptor(InstName.Und, InstEmit.Und), null);
         }
 
         private static int ToFastLookupIndex(int value)