Refactor marshaller method signatures and field usage

Removed redundant local variables and replaced them with direct usage of existing type and reference properties in marshaller method definitions. Updated method signatures and field assignments for clarity and consistency across Delegate, KeyValuePair, and Interface marshaller builders.

Author: Sergio0694

src/WinRT.Interop.Generator/Builders/InteropTypeDefinitionBuilder.Delegate.cs

@@ -640,7 +640,6 @@ public static void Marshaller(
             module.TopLevelTypes.Add(marshallerType);
 
             // Prepare the external types we need in the implemented methods
-            TypeSignature delegateType2 = delegateType;
             TypeSignature windowsRuntimeObjectReferenceValueType = interopReferences.WindowsRuntimeObjectReferenceValue.ToValueTypeSignature();
 
             // Define the 'ConvertToUnmanaged' method as follows:
@@ -651,7 +650,7 @@ public static void Marshaller(
                 attributes: MethodAttributes.Public | MethodAttributes.Static | MethodAttributes.HideBySig,
                 signature: MethodSignature.CreateStatic(
                     returnType: windowsRuntimeObjectReferenceValueType,
-                    parameterTypes: [delegateType2]))
+                    parameterTypes: [delegateType]))
             {
                 CilInstructions =
                 {
@@ -676,14 +675,14 @@ public static void Marshaller(
                 name: "ConvertToManaged"u8,
                 attributes: MethodAttributes.Public | MethodAttributes.Static | MethodAttributes.HideBySig,
                 signature: MethodSignature.CreateStatic(
-                    returnType: delegateType2,
+                    returnType: delegateType,
                     parameterTypes: [module.CorLibTypeFactory.Void.MakePointerType()]))
             {
                 CilInstructions =
                 {
                     { Ldarg_0 },
                     { Call, windowsRuntimeDelegateMarshallerConvertToManaged },
-                    { Castclass, delegateType2.ToTypeDefOrRef() },
+                    { Castclass, delegateType.ToTypeDefOrRef() },
                     { Ret }
                 }
             };
@@ -698,7 +697,7 @@ public static void Marshaller(
                 attributes: MethodAttributes.Public | MethodAttributes.Static | MethodAttributes.HideBySig,
                 signature: MethodSignature.CreateStatic(
                     returnType: windowsRuntimeObjectReferenceValueType,
-                    parameterTypes: [delegateType2]))
+                    parameterTypes: [delegateType]))
             {
                 CilInstructions =
                 {
@@ -723,7 +722,7 @@ public static void Marshaller(
                 name: "UnboxToManaged"u8,
                 attributes: MethodAttributes.Public | MethodAttributes.Static | MethodAttributes.HideBySig,
                 signature: MethodSignature.CreateStatic(
-                    returnType: delegateType2,
+                    returnType: delegateType,
                     parameterTypes: [module.CorLibTypeFactory.Void.MakePointerType()]))
             {
                 CilInstructions =

src/WinRT.Interop.Generator/Builders/InteropTypeDefinitionBuilder.KeyValuePair.cs

@@ -139,10 +139,6 @@ public static void Marshaller(
             // Track the type (it may be needed to marshal parameters or return values)
             emitState.TrackTypeDefinition(marshallerType, keyValuePairType, "Marshaller");
 
-            // Prepare the external types we need in the implemented methods
-            TypeSignature typeSignature2 = keyValuePairType;
-            TypeSignature windowsRuntimeObjectReferenceValueType = interopReferences.WindowsRuntimeObjectReferenceValue.ToValueTypeSignature();
-
             // Determine which 'CreateComInterfaceFlags' flags we use for the marshalled CCW
             CreateComInterfaceFlags flags = keyValuePairType.IsTrackerSupportRequired(interopReferences)
                 ? CreateComInterfaceFlags.TrackerSupport
@@ -155,8 +151,8 @@ public static void Marshaller(
                 name: "ConvertToUnmanaged"u8,
                 attributes: MethodAttributes.Public | MethodAttributes.Static | MethodAttributes.HideBySig,
                 signature: MethodSignature.CreateStatic(
-                    returnType: windowsRuntimeObjectReferenceValueType,
-                    parameterTypes: [typeSignature2]))
+                    returnType: interopReferences.WindowsRuntimeObjectReferenceValue.ToValueTypeSignature(),
+                    parameterTypes: [keyValuePairType]))
             {
                 CilInstructions =
                 {
@@ -185,7 +181,7 @@ public static void Marshaller(
                 name: "ConvertToManaged"u8,
                 attributes: MethodAttributes.Public | MethodAttributes.Static | MethodAttributes.HideBySig,
                 signature: MethodSignature.CreateStatic(
-                    returnType: typeSignature2,
+                    returnType: keyValuePairType,
                     parameterTypes: [module.CorLibTypeFactory.Void.MakePointerType()]))
             {
                 CilLocalVariables = { loc_0_default },

src/WinRT.Interop.Generator/Builders/InteropTypeDefinitionBuilder.cs

@@ -303,28 +303,21 @@ private static void Marshaller(
 
         module.TopLevelTypes.Add(marshallerType);
 
-        // Prepare the external types we need in the implemented methods
-        TypeSignature typeSignature2 = typeSignature;
-        TypeSignature windowsRuntimeObjectReferenceValueType = interopReferences.WindowsRuntimeObjectReferenceValue.ToValueTypeSignature();
-
-        // Reference the instantiated 'ConvertToUnmanaged' method for the marshaller
-        MemberReference windowsRuntimeInterfaceMarshallerConvertToUnmanaged = interopReferences.WindowsRuntimeInterfaceMarshallerConvertToUnmanaged(typeSignature);
-
         // Define the 'ConvertToUnmanaged' method as follows:
         //
         // public static WindowsRuntimeObjectReferenceValue ConvertToUnmanaged(<INTERFACE_TYPE> value)
         MethodDefinition convertToUnmanagedMethod = new(
             name: "ConvertToUnmanaged"u8,
             attributes: MethodAttributes.Public | MethodAttributes.Static | MethodAttributes.HideBySig,
             signature: MethodSignature.CreateStatic(
-                returnType: windowsRuntimeObjectReferenceValueType,
-                parameterTypes: [typeSignature2]))
+                returnType: interopReferences.WindowsRuntimeObjectReferenceValue.ToValueTypeSignature(),
+                parameterTypes: [typeSignature]))
         {
             CilInstructions =
             {
                 { Ldarg_0 },
                 { Call, get_IidMethod },
-                { Call, windowsRuntimeInterfaceMarshallerConvertToUnmanaged },
+                { Call, interopReferences.WindowsRuntimeInterfaceMarshallerConvertToUnmanaged(typeSignature) },
                 { Ret }
             }
         };
@@ -343,14 +336,14 @@ private static void Marshaller(
             name: "ConvertToManaged"u8,
             attributes: MethodAttributes.Public | MethodAttributes.Static | MethodAttributes.HideBySig,
             signature: MethodSignature.CreateStatic(
-                returnType: typeSignature2,
+                returnType: typeSignature,
                 parameterTypes: [module.CorLibTypeFactory.Void.MakePointerType()]))
         {
             CilInstructions =
             {
                 { Ldarg_0 },
                 { Call, windowsRuntimeUnsealedObjectMarshallerConvertToManaged },
-                { Castclass, typeSignature2.ToTypeDefOrRef() },
+                { Castclass, typeSignature.ToTypeDefOrRef() },
                 { Ret }
             }
         };
@@ -596,12 +589,6 @@ private static void InterfaceEntriesImpl<TArg>(
         // Create the static constructor to initialize the interface entries
         MethodDefinition cctor = implType.GetOrCreateStaticConstructor(module);
 
-        // Import the target fields (they have to be in the module, or the resulting assembly won't be valid):
-        //   - [0]: Guid IID
-        //   - [1]: nint Vtable
-        IFieldDescriptor comInterfaceEntryIIDField = interopReferences.ComInterfaceEntryIID;
-        IFieldDescriptor comInterfaceEntryVtableField = interopReferences.ComInterfaceEntryVtable;
-
         // We need to create a new method body bound to this constructor
         CilInstructionCollection cctorInstructions = cctor.CilMethodBody!.Instructions;
 
@@ -622,14 +609,14 @@ private static void InterfaceEntriesImpl<TArg>(
             // Invoke the callback to emit code to load 'IID' on the evaluation stack
             get_IID(implTypes[i], cctorInstructions, interopReferences, module);
 
-            _ = cctorInstructions.Add(Stfld, comInterfaceEntryIIDField);
+            _ = cctorInstructions.Add(Stfld, interopReferences.ComInterfaceEntryIID);
             _ = cctorInstructions.Add(Ldsflda, entriesField);
             _ = cctorInstructions.Add(Ldflda, entriesFieldType.Fields[i]);
 
             // Same as above, but to get the vtable pointer on the stack
             get_Vtable(implTypes[i], cctorInstructions, interopReferences, module);
 
-            _ = cctorInstructions.Add(Stfld, comInterfaceEntryVtableField);
+            _ = cctorInstructions.Add(Stfld, interopReferences.ComInterfaceEntryVtable);
         }
 
         _ = cctorInstructions.Add(Ret);