private AssignStatement SetDelegate(LocalReference localDelegate, ReferenceExpression localTarget,
Type closedDelegateType, MethodInfo closedMethodOnTarget)
{
var delegateCreateDelegate = new MethodInvocationExpression(
null,
DelegateMethods.CreateDelegate,
new TypeTokenExpression(closedDelegateType),
localTarget,
new MethodTokenExpression(closedMethodOnTarget));
return new AssignStatement(localDelegate, new ConvertExpression(closedDelegateType, delegateCreateDelegate));
}
private FieldReference BuildDelegateToken(ClassEmitter proxy)
{
var callback = proxy.CreateStaticField(namingScope.GetUniqueName("callback_" + method.Method.Name), delegateType);
var createDelegate = new MethodInvocationExpression(
null,
DelegateMethods.CreateDelegate,
new TypeTokenExpression(delegateType),
NullExpression.Instance,
new MethodTokenExpression(method.MethodOnTarget));
var bindDelegate = new AssignStatement(callback, new ConvertExpression(delegateType, createDelegate));
proxy.ClassConstructor.CodeBuilder.AddStatement(bindDelegate);
return callback;
}
protected override MethodEmitter BuildProxiedMethodBody(MethodEmitter emitter, ClassEmitter @class, ProxyGenerationOptions options, INamingScope namingScope)
{
var invocationType = invocation;
Trace.Assert(MethodToOverride.IsGenericMethod == invocationType.IsGenericTypeDefinition);
var genericArguments = Type.EmptyTypes;
var constructor = invocation.GetConstructors()[0];
Expression proxiedMethodTokenExpression;
if (MethodToOverride.IsGenericMethod)
{
// bind generic method arguments to invocation's type arguments
genericArguments = emitter.MethodBuilder.GetGenericArguments();
invocationType = invocationType.MakeGenericType(genericArguments);
constructor = TypeBuilder.GetConstructor(invocationType, constructor);
// Not in the cache: generic method
proxiedMethodTokenExpression = new MethodTokenExpression(MethodToOverride.MakeGenericMethod(genericArguments));
}
else
{
var proxiedMethodToken = @class.CreateStaticField(namingScope.GetUniqueName("token_" + MethodToOverride.Name), typeof(MethodInfo));
@class.ClassConstructor.CodeBuilder.AddStatement(new AssignStatement(proxiedMethodToken, new MethodTokenExpression(MethodToOverride)));
proxiedMethodTokenExpression = proxiedMethodToken.ToExpression();
}
var methodInterceptors = SetMethodInterceptors(@class, namingScope, emitter, proxiedMethodTokenExpression);
var dereferencedArguments = IndirectReference.WrapIfByRef(emitter.Arguments);
var hasByRefArguments = HasByRefArguments(emitter.Arguments);
var arguments = GetCtorArguments(@class, proxiedMethodTokenExpression, dereferencedArguments, methodInterceptors);
var ctorArguments = ModifyArguments(@class, arguments);
var invocationLocal = emitter.CodeBuilder.DeclareLocal(invocationType);
emitter.CodeBuilder.AddStatement(new AssignStatement(invocationLocal,
new NewInstanceExpression(constructor, ctorArguments)));
if (MethodToOverride.ContainsGenericParameters)
{
EmitLoadGenricMethodArguments(emitter, MethodToOverride.MakeGenericMethod(genericArguments), invocationLocal);
}
if (hasByRefArguments)
{
emitter.CodeBuilder.AddStatement(new TryStatement());
}
var proceed = new ExpressionStatement(new MethodInvocationExpression(invocationLocal, InvocationMethods.Proceed));
emitter.CodeBuilder.AddStatement(proceed);
if (hasByRefArguments)
{
emitter.CodeBuilder.AddStatement(new FinallyStatement());
}
GeneratorUtil.CopyOutAndRefParameters(dereferencedArguments, invocationLocal, MethodToOverride, emitter);
if (hasByRefArguments)
{
emitter.CodeBuilder.AddStatement(new EndExceptionBlockStatement());
}
if (MethodToOverride.ReturnType != typeof(void))
{
// Emit code to return with cast from ReturnValue
var getRetVal = new MethodInvocationExpression(invocationLocal, InvocationMethods.GetReturnValue);
emitter.CodeBuilder.AddStatement(new ReturnStatement(new ConvertExpression(emitter.ReturnType, getRetVal)));
}
else
{
emitter.CodeBuilder.AddStatement(new ReturnStatement());
}
return emitter;
}
private Expression SetMethodInterceptors(ClassEmitter @class, INamingScope namingScope, MethodEmitter emitter, Expression proxiedMethodTokenExpression)
{
var selector = @class.GetField("__selector");
if(selector == null)
{
return null;
}
var methodInterceptorsField = BuildMethodInterceptorsField(@class, MethodToOverride, namingScope);
var emptyInterceptors = new NewArrayExpression(0, typeof(IInterceptor));
var selectInterceptors = new MethodInvocationExpression(selector, InterceptorSelectorMethods.SelectInterceptors,
new MethodInvocationExpression(null,
TypeUtilMethods.GetTypeOrNull,
getTargetExpression(@class, MethodToOverride)),
proxiedMethodTokenExpression, interceptors.ToExpression())
{ VirtualCall = true };
emitter.CodeBuilder.AddExpression(
new IfNullExpression(methodInterceptorsField,
new AssignStatement(methodInterceptorsField,
new NullCoalescingOperatorExpression(selectInterceptors, emptyInterceptors))));
return methodInterceptorsField.ToExpression();
}