System.Xml.Xsl.IlGen.XmlILVisitor.VisitInvoke C# (CSharp) Method

        protected override QilNode VisitInvoke(QilInvoke ndInvoke) {
            QilFunction ndFunc = ndInvoke.Function;
            MethodInfo methInfo = XmlILAnnotation.Write(ndFunc).FunctionBinding;
            bool useWriter = (XmlILConstructInfo.Read(ndFunc).ConstructMethod == XmlILConstructMethod.Writer);
            Debug.Assert(!XmlILConstructInfo.Read(ndInvoke).PushToWriterFirst || useWriter);

            // Push XmlQueryRuntime onto the stack as the first parameter
            this.helper.LoadQueryRuntime();

            // Generate code to push each Invoke argument onto the stack
            for (int iArg = 0; iArg < ndInvoke.Arguments.Count; iArg++) {
                QilNode ndActualArg = ndInvoke.Arguments[iArg];
                QilNode ndFormalArg = ndInvoke.Function.Arguments[iArg];
                NestedVisitEnsureStack(ndActualArg, GetItemStorageType(ndFormalArg), !ndFormalArg.XmlType.IsSingleton);
            }

            // Check whether this call should compiled using the .tailcall instruction
            if (OptimizerPatterns.Read(ndInvoke).MatchesPattern(OptimizerPatternName.TailCall))
                this.helper.TailCall(methInfo);
            else
                this.helper.Call(methInfo);

            // If function's results are not pushed to Writer,
            if (!useWriter) {
                // Return value is on the stack; ensure it has the correct storage type
                this.iterCurr.Storage = StorageDescriptor.Stack(GetItemStorageType(ndInvoke), !ndInvoke.XmlType.IsSingleton);
            }
            else {
                this.iterCurr.Storage = StorageDescriptor.None();
            }

            return ndInvoke;
        }