protected virtual Func <object, object[], object> CreateInvoker()
{
DynamicMethod dynamicMethod = new DynamicMethod($"invoker_{_displayName}",
typeof(object), new Type[] { typeof(object), typeof(object[]) }, _reflectionInfo.Module, true);
ILGenerator ilGen = dynamicMethod.GetILGenerator();
var parameterTypes = _reflectionInfo.GetParameterTypes();
ilGen.EmitLoadArg(0);
ilGen.EmitConvertFromObject(_reflectionInfo.DeclaringType);
if (parameterTypes.Length == 0)
{
return(CreateDelegate());
}
var refParameterCount = parameterTypes.Count(x => x.IsByRef);
if (refParameterCount == 0)
{
for (var i = 0; i < parameterTypes.Length; i++)
{
ilGen.EmitLoadArg(1);
ilGen.EmitInt(i);
ilGen.Emit(OpCodes.Ldelem_Ref);
ilGen.EmitConvertFromObject(parameterTypes[i]);
}
return(CreateDelegate());
}
var indexedLocals = new IndexedLocalBuilder[refParameterCount];
var index = 0;
for (var i = 0; i < parameterTypes.Length; i++)
{
ilGen.EmitLoadArg(1);
ilGen.EmitInt(i);
ilGen.Emit(OpCodes.Ldelem_Ref);
if (parameterTypes[i].IsByRef)
{
var defType = parameterTypes[i].GetElementType();
var indexedLocal = new IndexedLocalBuilder(ilGen.DeclareLocal(defType), i);
indexedLocals[index++] = indexedLocal;
ilGen.EmitConvertFromObject(defType);
ilGen.Emit(OpCodes.Stloc, indexedLocal.LocalBuilder);
ilGen.Emit(OpCodes.Ldloca, indexedLocal.LocalBuilder);
}
else
{
ilGen.EmitConvertFromObject(parameterTypes[i]);
}
}
return(CreateDelegate(() =>
{
for (var i = 0; i < indexedLocals.Length; i++)
{
ilGen.EmitLoadArg(1);
ilGen.EmitInt(indexedLocals[i].Index);
ilGen.Emit(OpCodes.Ldloc, indexedLocals[i].LocalBuilder);
ilGen.EmitConvertToObject(indexedLocals[i].LocalType);
ilGen.Emit(OpCodes.Stelem_Ref);
}
}));
Func <object, object[], object> CreateDelegate(Action callback = null)
{
ilGen.EmitCall(OpCodes.Callvirt, _reflectionInfo, null);
callback?.Invoke();
if (_reflectionInfo.ReturnType == typeof(void))
{
ilGen.Emit(OpCodes.Ldnull);
}
else if (_reflectionInfo.ReturnType.GetTypeInfo().IsValueType)
{
ilGen.EmitConvertToObject(_reflectionInfo.ReturnType);
}
ilGen.Emit(OpCodes.Ret);
return((Func <object, object[], object>)dynamicMethod.CreateDelegate(typeof(Func <object, object[], object>)));
}
}
private Func <object[], object> CreateInvoker()
{
var dynamicMethod = new DynamicMethod($"invoker-{Guid.NewGuid()}", typeof(object), new Type[] { typeof(object[]) }, Member.Module, true);
var ilGen = dynamicMethod.GetILGenerator();
if (Parameters.Length == 0)
{
ilGen.Emit(OpCodes.Newobj, Member);
return(CreateDelegate());
}
var parameterTypes = Parameters.Select(i => i.Member.ParameterType).ToArray();
var refParameterCount = parameterTypes.Count(x => x.IsByRef);
if (refParameterCount == 0)
{
for (var i = 0; i < parameterTypes.Length; i++)
{
ilGen.EmitLoadArg(0);
ilGen.EmitInt(i);
ilGen.Emit(OpCodes.Ldelem_Ref);
ilGen.EmitConvertFromObject(parameterTypes[i]);
}
ilGen.Emit(OpCodes.Newobj, Member);
return(CreateDelegate());
}
var indexedLocals = new IndexedLocalBuilder[refParameterCount];
var index = 0;
for (var i = 0; i < parameterTypes.Length; i++)
{
ilGen.EmitLoadArg(0);
ilGen.EmitInt(i);
ilGen.Emit(OpCodes.Ldelem_Ref);
if (parameterTypes[i].IsByRef)
{
var defType = parameterTypes[i].GetElementType();
var indexedLocal = new IndexedLocalBuilder(ilGen.DeclareLocal(defType), i);
indexedLocals[index++] = indexedLocal;
ilGen.EmitConvertFromObject(defType);
ilGen.Emit(OpCodes.Stloc, indexedLocal.LocalBuilder);
ilGen.Emit(OpCodes.Ldloca, indexedLocal.LocalBuilder);
}
else
{
ilGen.EmitConvertFromObject(parameterTypes[i]);
}
}
ilGen.Emit(OpCodes.Newobj, Member);
for (var i = 0; i < indexedLocals.Length; i++)
{
ilGen.EmitLoadArg(0);
ilGen.EmitInt(indexedLocals[i].Index);
ilGen.Emit(OpCodes.Ldloc, indexedLocals[i].LocalBuilder);
ilGen.EmitConvertToObject(indexedLocals[i].LocalType);
ilGen.Emit(OpCodes.Stelem_Ref);
}
return(CreateDelegate());
Func <object[], object> CreateDelegate()
{
if (Member.DeclaringType.GetTypeInfo().IsValueType)
{
ilGen.EmitConvertToObject(Member.DeclaringType);
}
ilGen.Emit(OpCodes.Ret);
return((Func <object[], object>)dynamicMethod.CreateDelegate(typeof(Func <object[], object>)));
}
}
