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

        private void StartForBinding(QilIterator ndFor, OptimizerPatterns patt) {
            LocalBuilder locPos = null;
            Debug.Assert(ndFor.XmlType.IsSingleton);

            // For expression iterator will be unnested as part of parent iterator
            if (this.iterCurr.HasLabelNext)
                StartNestedIterator(ndFor.Binding, this.iterCurr.GetLabelNext());
            else
                StartNestedIterator(ndFor.Binding);

            if (patt.MatchesPattern(OptimizerPatternName.IsPositional)) {
                // Need to track loop index so initialize it to 0 before starting loop
                locPos = this.helper.DeclareLocal("$$$pos", typeof(int));
                this.helper.Emit(OpCodes.Ldc_I4_0);
                this.helper.Emit(OpCodes.Stloc, locPos);
            }

            // Allow base internal class to dispatch based on QilExpression node type
            Visit(ndFor.Binding);

            // DebugInfo: Open variable scope
            // DebugInfo: Ensure that for variable is stored in a local and tag it with the user-defined name
            if (this.qil.IsDebug && ndFor.DebugName != null) {
                this.helper.DebugStartScope();

                // Ensure that values are stored in a local variable with a user-defined name
                this.iterCurr.EnsureLocalNoCache("$$$for");
                this.iterCurr.Storage.LocalLocation.SetLocalSymInfo(ndFor.DebugName);
            }
            else {
                // Ensure that values are not stored on the stack
                this.iterCurr.EnsureNoStackNoCache("$$$for");
            }

            if (patt.MatchesPattern(OptimizerPatternName.IsPositional)) {
                // Increment position
                this.helper.Emit(OpCodes.Ldloc, locPos);
                this.helper.Emit(OpCodes.Ldc_I4_1);
                this.helper.Emit(OpCodes.Add);
                this.helper.Emit(OpCodes.Stloc, locPos);

                if (patt.MatchesPattern(OptimizerPatternName.MaxPosition)) {
                    // Short-circuit rest of loop if max position has already been reached
                    this.helper.Emit(OpCodes.Ldloc, locPos);
                    this.helper.LoadInteger((int) patt.GetArgument(OptimizerPatternArgument.MaxPosition));
                    this.helper.Emit(OpCodes.Bgt, this.iterCurr.ParentIterator.GetLabelNext());
                }

                this.iterCurr.LocalPosition = locPos;
            }

            EndNestedIterator(ndFor.Binding);
            this.iterCurr.SetIterator(this.iterNested);
        }