GenerateHelper.cs source code in C# .NET

Source code for the .NET framework in C#

                        

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/ Dotnetfx_Vista_SP2 / Dotnetfx_Vista_SP2 / 8.0.50727.4016 / DEVDIV / depot / DevDiv / releases / whidbey / NetFxQFE / ndp / fx / src / XmlUtils / System / Xml / Xsl / IlGen / GenerateHelper.cs / 1 / GenerateHelper.cs

                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// [....] 
//-----------------------------------------------------------------------------
using System; 
using System.Globalization; 
using System.Xml;
using System.Xml.XPath; 
using System.Xml.Schema;
using System.Text;
using System.IO;
using System.Collections; 
using System.Collections.Generic;
using System.Reflection; 
using System.Reflection.Emit; 
using System.Security;
using System.Diagnostics; 
using System.Diagnostics.SymbolStore;
using System.Xml.Xsl.Qil;
using System.Xml.Xsl.Runtime;
 
namespace System.Xml.Xsl.IlGen {
    using Res = System.Xml.Utils.Res; 
 
    /// 
    /// List of all XmlIL runtime constructors. 
    /// 
    internal class XmlILStorageMethods {
        // Aggregates
        public MethodInfo AggAvg; 
        public MethodInfo AggAvgResult;
        public MethodInfo AggCreate; 
        public MethodInfo AggIsEmpty; 
        public MethodInfo AggMax;
        public MethodInfo AggMaxResult; 
        public MethodInfo AggMin;
        public MethodInfo AggMinResult;
        public MethodInfo AggSum;
        public MethodInfo AggSumResult; 

        // Sequences 
        public Type SeqType; 
        public FieldInfo SeqEmpty;
        public MethodInfo SeqReuse; 
        public MethodInfo SeqReuseSgl;
        public MethodInfo SeqAdd;
        public MethodInfo SeqSortByKeys;
 
        // IList<>
        public Type IListType; 
        public MethodInfo IListCount; 
        public MethodInfo IListItem;
 
        // XPathItem
        public MethodInfo ValueAs;

        // ToAtomicValue 
        public MethodInfo ToAtomicValue;
 
        public XmlILStorageMethods(Type storageType) { 
            // Aggregates
            if (storageType == typeof(int) || storageType == typeof(long) || 
                storageType == typeof(decimal) || storageType == typeof(double)) {

                Type aggType = Type.GetType("System.Xml.Xsl.Runtime." + storageType.Name + "Aggregator");
                AggAvg = XmlILMethods.GetMethod(aggType, "Average"); 
                AggAvgResult = XmlILMethods.GetMethod(aggType, "get_AverageResult");
                AggCreate = XmlILMethods.GetMethod(aggType, "Create"); 
                AggIsEmpty = XmlILMethods.GetMethod(aggType, "get_IsEmpty"); 
                AggMax = XmlILMethods.GetMethod(aggType, "Maximum");
                AggMaxResult = XmlILMethods.GetMethod(aggType, "get_MaximumResult"); 
                AggMin = XmlILMethods.GetMethod(aggType, "Minimum");
                AggMinResult = XmlILMethods.GetMethod(aggType, "get_MinimumResult");
                AggSum = XmlILMethods.GetMethod(aggType, "Sum");
                AggSumResult = XmlILMethods.GetMethod(aggType, "get_SumResult"); 
            }
 
            // Sequences 
            if (storageType == typeof(XPathNavigator)) {
                SeqType = typeof(XmlQueryNodeSequence); 
                SeqAdd = XmlILMethods.GetMethod(SeqType, "AddClone");
            }
            else if (storageType == typeof(XPathItem)) {
                SeqType = typeof(XmlQueryItemSequence); 
                SeqAdd = XmlILMethods.GetMethod(SeqType, "AddClone");
            } 
            else { 
                SeqType = typeof(XmlQuerySequence<>).MakeGenericType(storageType);
                SeqAdd = XmlILMethods.GetMethod(SeqType, "Add"); 
            }

            SeqEmpty = SeqType.GetField("Empty");
            SeqReuse = XmlILMethods.GetMethod(SeqType, "CreateOrReuse", SeqType); 
            SeqReuseSgl = XmlILMethods.GetMethod(SeqType, "CreateOrReuse", SeqType, storageType);
            SeqSortByKeys = XmlILMethods.GetMethod(SeqType, "SortByKeys"); 
 
            // IList<>
            IListType = typeof(IList<>).MakeGenericType(storageType); 
            IListItem = XmlILMethods.GetMethod(IListType, "get_Item");
            IListCount = XmlILMethods.GetMethod(typeof(ICollection<>).MakeGenericType(storageType), "get_Count");

            // XPathItem.ValueAsXXX 
            if (storageType == typeof(string))
                ValueAs = XmlILMethods.GetMethod(typeof(XPathItem), "get_Value"); 
            else if (storageType == typeof(int)) 
                ValueAs = XmlILMethods.GetMethod(typeof(XPathItem), "get_ValueAsInt");
            else if (storageType == typeof(long)) 
                ValueAs = XmlILMethods.GetMethod(typeof(XPathItem), "get_ValueAsLong");
            else if (storageType == typeof(DateTime))
                ValueAs = XmlILMethods.GetMethod(typeof(XPathItem), "get_ValueAsDateTime");
            else if (storageType == typeof(double)) 
                ValueAs = XmlILMethods.GetMethod(typeof(XPathItem), "get_ValueAsDouble");
            else if (storageType == typeof(bool)) 
                ValueAs = XmlILMethods.GetMethod(typeof(XPathItem), "get_ValueAsBoolean"); 

            // XmlILStorageConverter.XXXToAtomicValue 
            if (storageType == typeof(byte[]))
                ToAtomicValue = XmlILMethods.GetMethod(typeof(XmlILStorageConverter), "BytesToAtomicValue");
            else if (storageType != typeof(XPathItem) && storageType != typeof(XPathNavigator))
                ToAtomicValue = XmlILMethods.GetMethod(typeof(XmlILStorageConverter), storageType.Name + "ToAtomicValue"); 
        }
    } 
 
    /// 
    /// List of all XmlIL runtime constructors. 
    /// 
    internal static class XmlILConstructors {
        public static readonly ConstructorInfo DecFromParts = GetConstructor(typeof(decimal), typeof(int), typeof(int), typeof(int), typeof(bool), typeof(byte));
        public static readonly ConstructorInfo DecFromInt32 = GetConstructor(typeof(decimal), typeof(int)); 
        public static readonly ConstructorInfo DecFromInt64 = GetConstructor(typeof(decimal), typeof(long));
        public static readonly ConstructorInfo Debuggable = GetConstructor(typeof(DebuggableAttribute), typeof(DebuggableAttribute.DebuggingModes)); 
        public static readonly ConstructorInfo NonUserCode = GetConstructor(typeof(DebuggerNonUserCodeAttribute)); 
        public static readonly ConstructorInfo QName = GetConstructor(typeof(XmlQualifiedName), typeof(string), typeof(string));
        public static readonly ConstructorInfo StepThrough = GetConstructor(typeof(DebuggerStepThroughAttribute)); 
        public static readonly ConstructorInfo Transparent = GetConstructor(typeof(SecurityTransparentAttribute));

        private static ConstructorInfo GetConstructor(Type className) {
            ConstructorInfo constrInfo = className.GetConstructor(new Type[] {}); 
            Debug.Assert(constrInfo != null, "Constructor " + className + " cannot be null.");
            return constrInfo; 
        } 

        private static ConstructorInfo GetConstructor(Type className, params Type[] args) { 
            ConstructorInfo constrInfo = className.GetConstructor(args);
            Debug.Assert(constrInfo != null, "Constructor " + className + " cannot be null.");
            return constrInfo;
        } 
    }
 
 
    /// 
    /// List of all XmlIL runtime methods. 
    /// 
    internal static class XmlILMethods {
        // Iterators
        public static readonly MethodInfo AncCreate = GetMethod(typeof(AncestorIterator), "Create"); 
        public static readonly MethodInfo AncNext = GetMethod(typeof(AncestorIterator), "MoveNext");
        public static readonly MethodInfo AncDOCreate = GetMethod(typeof(AncestorDocOrderIterator), "Create"); 
        public static readonly MethodInfo AncDONext = GetMethod(typeof(AncestorDocOrderIterator), "MoveNext"); 
        public static readonly MethodInfo AttrContentCreate = GetMethod(typeof(AttributeContentIterator), "Create");
        public static readonly MethodInfo AttrContentNext = GetMethod(typeof(AttributeContentIterator), "MoveNext"); 
        public static readonly MethodInfo AttrCreate = GetMethod(typeof(AttributeIterator), "Create");
        public static readonly MethodInfo AttrNext = GetMethod(typeof(AttributeIterator), "MoveNext");
        public static readonly MethodInfo ContentCreate = GetMethod(typeof(ContentIterator), "Create");
        public static readonly MethodInfo ContentNext = GetMethod(typeof(ContentIterator), "MoveNext"); 
        public static readonly MethodInfo ContentMergeCreate = GetMethod(typeof(ContentMergeIterator), "Create");
        public static readonly MethodInfo ContentMergeNext = GetMethod(typeof(ContentMergeIterator), "MoveNext"); 
        public static readonly MethodInfo DescCreate = GetMethod(typeof(DescendantIterator), "Create"); 
        public static readonly MethodInfo DescNext = GetMethod(typeof(DescendantIterator), "MoveNext");
        public static readonly MethodInfo DescMergeCreate = GetMethod(typeof(DescendantMergeIterator), "Create"); 
        public static readonly MethodInfo DescMergeNext = GetMethod(typeof(DescendantMergeIterator), "MoveNext");
        public static readonly MethodInfo DiffCreate = GetMethod(typeof(DifferenceIterator), "Create");
        public static readonly MethodInfo DiffNext = GetMethod(typeof(DifferenceIterator), "MoveNext");
        public static readonly MethodInfo DodMergeCreate = GetMethod(typeof(DodSequenceMerge), "Create"); 
        public static readonly MethodInfo DodMergeAdd = GetMethod(typeof(DodSequenceMerge), "AddSequence");
        public static readonly MethodInfo DodMergeSeq = GetMethod(typeof(DodSequenceMerge), "MergeSequences"); 
        public static readonly MethodInfo ElemContentCreate = GetMethod(typeof(ElementContentIterator), "Create"); 
        public static readonly MethodInfo ElemContentNext = GetMethod(typeof(ElementContentIterator), "MoveNext");
        public static readonly MethodInfo FollSibCreate = GetMethod(typeof(FollowingSiblingIterator), "Create"); 
        public static readonly MethodInfo FollSibNext = GetMethod(typeof(FollowingSiblingIterator), "MoveNext");
        public static readonly MethodInfo FollSibMergeCreate = GetMethod(typeof(FollowingSiblingMergeIterator), "Create");
        public static readonly MethodInfo FollSibMergeNext = GetMethod(typeof(FollowingSiblingMergeIterator), "MoveNext");
        public static readonly MethodInfo IdCreate = GetMethod(typeof(IdIterator), "Create"); 
        public static readonly MethodInfo IdNext = GetMethod(typeof(IdIterator), "MoveNext");
        public static readonly MethodInfo InterCreate = GetMethod(typeof(IntersectIterator), "Create"); 
        public static readonly MethodInfo InterNext = GetMethod(typeof(IntersectIterator), "MoveNext"); 
        public static readonly MethodInfo KindContentCreate = GetMethod(typeof(NodeKindContentIterator), "Create");
        public static readonly MethodInfo KindContentNext = GetMethod(typeof(NodeKindContentIterator), "MoveNext"); 
        public static readonly MethodInfo NmspCreate = GetMethod(typeof(NamespaceIterator), "Create");
        public static readonly MethodInfo NmspNext = GetMethod(typeof(NamespaceIterator), "MoveNext");
        public static readonly MethodInfo NodeRangeCreate = GetMethod(typeof(NodeRangeIterator), "Create");
        public static readonly MethodInfo NodeRangeNext = GetMethod(typeof(NodeRangeIterator), "MoveNext"); 
        public static readonly MethodInfo ParentCreate = GetMethod(typeof(ParentIterator), "Create");
        public static readonly MethodInfo ParentNext = GetMethod(typeof(ParentIterator), "MoveNext"); 
        public static readonly MethodInfo PrecCreate = GetMethod(typeof(PrecedingIterator), "Create"); 
        public static readonly MethodInfo PrecNext = GetMethod(typeof(PrecedingIterator), "MoveNext");
        public static readonly MethodInfo PreSibCreate = GetMethod(typeof(PrecedingSiblingIterator), "Create"); 
        public static readonly MethodInfo PreSibNext = GetMethod(typeof(PrecedingSiblingIterator), "MoveNext");
        public static readonly MethodInfo PreSibDOCreate = GetMethod(typeof(PrecedingSiblingDocOrderIterator), "Create");
        public static readonly MethodInfo PreSibDONext = GetMethod(typeof(PrecedingSiblingDocOrderIterator), "MoveNext");
        public static readonly MethodInfo SortKeyCreate = GetMethod(typeof(XmlSortKeyAccumulator), "Create"); 
        public static readonly MethodInfo SortKeyDateTime = GetMethod(typeof(XmlSortKeyAccumulator), "AddDateTimeSortKey");
        public static readonly MethodInfo SortKeyDecimal = GetMethod(typeof(XmlSortKeyAccumulator), "AddDecimalSortKey"); 
        public static readonly MethodInfo SortKeyDouble = GetMethod(typeof(XmlSortKeyAccumulator), "AddDoubleSortKey"); 
        public static readonly MethodInfo SortKeyEmpty = GetMethod(typeof(XmlSortKeyAccumulator), "AddEmptySortKey");
        public static readonly MethodInfo SortKeyFinish = GetMethod(typeof(XmlSortKeyAccumulator), "FinishSortKeys"); 
        public static readonly MethodInfo SortKeyInt = GetMethod(typeof(XmlSortKeyAccumulator), "AddIntSortKey");
        public static readonly MethodInfo SortKeyInteger = GetMethod(typeof(XmlSortKeyAccumulator), "AddIntegerSortKey");
        public static readonly MethodInfo SortKeyKeys = GetMethod(typeof(XmlSortKeyAccumulator), "get_Keys");
        public static readonly MethodInfo SortKeyString = GetMethod(typeof(XmlSortKeyAccumulator), "AddStringSortKey"); 
        public static readonly MethodInfo UnionCreate = GetMethod(typeof(UnionIterator), "Create");
        public static readonly MethodInfo UnionNext = GetMethod(typeof(UnionIterator), "MoveNext"); 
        public static readonly MethodInfo XPFollCreate = GetMethod(typeof(XPathFollowingIterator), "Create"); 
        public static readonly MethodInfo XPFollNext = GetMethod(typeof(XPathFollowingIterator), "MoveNext");
        public static readonly MethodInfo XPFollMergeCreate = GetMethod(typeof(XPathFollowingMergeIterator), "Create"); 
        public static readonly MethodInfo XPFollMergeNext = GetMethod(typeof(XPathFollowingMergeIterator), "MoveNext");
        public static readonly MethodInfo XPPrecCreate = GetMethod(typeof(XPathPrecedingIterator), "Create");
        public static readonly MethodInfo XPPrecNext = GetMethod(typeof(XPathPrecedingIterator), "MoveNext");
        public static readonly MethodInfo XPPrecDOCreate = GetMethod(typeof(XPathPrecedingDocOrderIterator), "Create"); 
        public static readonly MethodInfo XPPrecDONext = GetMethod(typeof(XPathPrecedingDocOrderIterator), "MoveNext");
        public static readonly MethodInfo XPPrecMergeCreate = GetMethod(typeof(XPathPrecedingMergeIterator), "Create"); 
        public static readonly MethodInfo XPPrecMergeNext = GetMethod(typeof(XPathPrecedingMergeIterator), "MoveNext"); 

        // XmlQueryRuntime 
        public static readonly MethodInfo AddNewIndex = GetMethod(typeof(XmlQueryRuntime), "AddNewIndex");
        public static readonly MethodInfo ChangeTypeXsltArg = GetMethod(typeof(XmlQueryRuntime), "ChangeTypeXsltArgument", typeof(int), typeof(object), typeof(Type));
        public static readonly MethodInfo ChangeTypeXsltResult = GetMethod(typeof(XmlQueryRuntime), "ChangeTypeXsltResult");
        public static readonly MethodInfo CompPos = GetMethod(typeof(XmlQueryRuntime), "ComparePosition"); 
        public static readonly MethodInfo Context = GetMethod(typeof(XmlQueryRuntime), "get_ExternalContext");
        public static readonly MethodInfo CreateCollation = GetMethod(typeof(XmlQueryRuntime), "CreateCollation"); 
        public static readonly MethodInfo DocOrder = GetMethod(typeof(XmlQueryRuntime), "DocOrderDistinct"); 
        public static readonly MethodInfo EndRtfConstr = GetMethod(typeof(XmlQueryRuntime), "EndRtfConstruction");
        public static readonly MethodInfo EndSeqConstr = GetMethod(typeof(XmlQueryRuntime), "EndSequenceConstruction"); 
        public static readonly MethodInfo FindIndex = GetMethod(typeof(XmlQueryRuntime), "FindIndex");
        public static readonly MethodInfo GenId = GetMethod(typeof(XmlQueryRuntime), "GenerateId");
        public static readonly MethodInfo GetAtomizedName = GetMethod(typeof(XmlQueryRuntime), "GetAtomizedName");
        public static readonly MethodInfo GetCollation = GetMethod(typeof(XmlQueryRuntime), "GetCollation"); 
        public static readonly MethodInfo GetEarly = GetMethod(typeof(XmlQueryRuntime), "GetEarlyBoundObject");
        public static readonly MethodInfo GetNameFilter = GetMethod(typeof(XmlQueryRuntime), "GetNameFilter"); 
        public static readonly MethodInfo GetOutput = GetMethod(typeof(XmlQueryRuntime), "get_Output"); 
        public static readonly MethodInfo GetGlobalValue = GetMethod(typeof(XmlQueryRuntime), "GetGlobalValue");
        public static readonly MethodInfo GetTypeFilter = GetMethod(typeof(XmlQueryRuntime), "GetTypeFilter"); 
        public static readonly MethodInfo GlobalComputed = GetMethod(typeof(XmlQueryRuntime), "IsGlobalComputed");
        public static readonly MethodInfo ItemMatchesCode = GetMethod(typeof(XmlQueryRuntime), "MatchesXmlType", typeof(XPathItem), typeof(XmlTypeCode));
        public static readonly MethodInfo ItemMatchesType = GetMethod(typeof(XmlQueryRuntime), "MatchesXmlType", typeof(XPathItem), typeof(int));
        public static readonly MethodInfo QNameEqualLit = GetMethod(typeof(XmlQueryRuntime), "IsQNameEqual", typeof(XPathNavigator), typeof(int), typeof(int)); 
        public static readonly MethodInfo QNameEqualNav = GetMethod(typeof(XmlQueryRuntime), "IsQNameEqual", typeof(XPathNavigator), typeof(XPathNavigator));
        public static readonly MethodInfo RtfConstr = GetMethod(typeof(XmlQueryRuntime), "TextRtfConstruction"); 
        public static readonly MethodInfo SendMessage = GetMethod(typeof(XmlQueryRuntime), "SendMessage"); 
        public static readonly MethodInfo SeqMatchesCode = GetMethod(typeof(XmlQueryRuntime), "MatchesXmlType", typeof(IList), typeof(XmlTypeCode));
        public static readonly MethodInfo SeqMatchesType = GetMethod(typeof(XmlQueryRuntime), "MatchesXmlType", typeof(IList), typeof(int)); 
        public static readonly MethodInfo SetGlobalValue = GetMethod(typeof(XmlQueryRuntime), "SetGlobalValue");
        public static readonly MethodInfo StartRtfConstr = GetMethod(typeof(XmlQueryRuntime), "StartRtfConstruction");
        public static readonly MethodInfo StartSeqConstr = GetMethod(typeof(XmlQueryRuntime), "StartSequenceConstruction");
        public static readonly MethodInfo TagAndMappings = GetMethod(typeof(XmlQueryRuntime), "ParseTagName", typeof(string), typeof(int)); 
        public static readonly MethodInfo TagAndNamespace = GetMethod(typeof(XmlQueryRuntime), "ParseTagName", typeof(string), typeof(string));
        public static readonly MethodInfo ThrowException = GetMethod(typeof(XmlQueryRuntime), "ThrowException"); 
        public static readonly MethodInfo XsltLib = GetMethod(typeof(XmlQueryRuntime), "get_XsltFunctions"); 

        // XmlQueryContext 
        public static readonly MethodInfo GetDataSource = GetMethod(typeof(XmlQueryContext), "GetDataSource");
        public static readonly MethodInfo GetDefaultDataSource = GetMethod(typeof(XmlQueryContext), "get_DefaultDataSource");
        public static readonly MethodInfo GetParam = GetMethod(typeof(XmlQueryContext), "GetParameter");
        public static readonly MethodInfo InvokeXsltLate = GetMethod(typeof(XmlQueryContext), "InvokeXsltLateBoundFunction"); 

        // XmlILIndex 
        public static readonly MethodInfo IndexAdd = GetMethod(typeof(XmlILIndex), "Add"); 
        public static readonly MethodInfo IndexLookup = GetMethod(typeof(XmlILIndex), "Lookup");
 
        // XPathItem
        public static readonly MethodInfo ItemIsNode = GetMethod(typeof(XPathItem), "get_IsNode");
        public static readonly MethodInfo Value = GetMethod(typeof(XPathItem), "get_Value");
        public static readonly MethodInfo ValueAsAny = GetMethod(typeof(XPathItem), "ValueAs", typeof(Type), typeof(IXmlNamespaceResolver)); 

        // XPathNavigator 
        public static readonly MethodInfo NavClone = GetMethod(typeof(XPathNavigator), "Clone"); 
        public static readonly MethodInfo NavLocalName = GetMethod(typeof(XPathNavigator), "get_LocalName");
        public static readonly MethodInfo NavMoveAttr = GetMethod(typeof(XPathNavigator), "MoveToAttribute", typeof(string), typeof(string)); 
        public static readonly MethodInfo NavMoveId = GetMethod(typeof(XPathNavigator), "MoveToId");
        public static readonly MethodInfo NavMoveParent = GetMethod(typeof(XPathNavigator), "MoveToParent");
        public static readonly MethodInfo NavMoveRoot = GetMethod(typeof(XPathNavigator), "MoveToRoot");
        public static readonly MethodInfo NavMoveTo = GetMethod(typeof(XPathNavigator), "MoveTo"); 
        public static readonly MethodInfo NavNmsp = GetMethod(typeof(XPathNavigator), "get_NamespaceURI");
        public static readonly MethodInfo NavPrefix = GetMethod(typeof(XPathNavigator), "get_Prefix"); 
        public static readonly MethodInfo NavSamePos = GetMethod(typeof(XPathNavigator), "IsSamePosition"); 
        public static readonly MethodInfo NavType = GetMethod(typeof(XPathNavigator), "get_NodeType");
 
        // XmlQueryOutput methods
        public static readonly MethodInfo StartElemLitName = GetMethod(typeof(XmlQueryOutput), "WriteStartElement", typeof(string), typeof(string), typeof(string));
        public static readonly MethodInfo StartElemLocName = GetMethod(typeof(XmlQueryOutput), "WriteStartElementLocalName", typeof(string));
        public static readonly MethodInfo EndElemStackName = GetMethod(typeof(XmlQueryOutput), "WriteEndElement"); 
        public static readonly MethodInfo StartAttrLitName = GetMethod(typeof(XmlQueryOutput), "WriteStartAttribute", typeof(string), typeof(string), typeof(string));
        public static readonly MethodInfo StartAttrLocName = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeLocalName", typeof(string)); 
        public static readonly MethodInfo EndAttr = GetMethod(typeof(XmlQueryOutput), "WriteEndAttribute"); 
        public static readonly MethodInfo Text = GetMethod(typeof(XmlQueryOutput), "WriteString");
        public static readonly MethodInfo NoEntText = GetMethod(typeof(XmlQueryOutput), "WriteRaw", typeof(string)); 

        public static readonly MethodInfo StartTree = GetMethod(typeof(XmlQueryOutput), "StartTree");
        public static readonly MethodInfo EndTree = GetMethod(typeof(XmlQueryOutput), "EndTree");
 
        public static readonly MethodInfo StartElemLitNameUn = GetMethod(typeof(XmlQueryOutput), "WriteStartElementUnchecked", typeof(string), typeof(string), typeof(string));
        public static readonly MethodInfo StartElemLocNameUn = GetMethod(typeof(XmlQueryOutput), "WriteStartElementUnchecked", typeof(string)); 
        public static readonly MethodInfo StartContentUn = GetMethod(typeof(XmlQueryOutput), "StartElementContentUnchecked"); 
        public static readonly MethodInfo EndElemLitNameUn = GetMethod(typeof(XmlQueryOutput), "WriteEndElementUnchecked", typeof(string), typeof(string), typeof(string));
        public static readonly MethodInfo EndElemLocNameUn = GetMethod(typeof(XmlQueryOutput), "WriteEndElementUnchecked", typeof(string)); 
        public static readonly MethodInfo StartAttrLitNameUn = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeUnchecked", typeof(string), typeof(string), typeof(string));
        public static readonly MethodInfo StartAttrLocNameUn = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeUnchecked", typeof(string));
        public static readonly MethodInfo EndAttrUn = GetMethod(typeof(XmlQueryOutput), "WriteEndAttributeUnchecked");
        public static readonly MethodInfo NamespaceDeclUn = GetMethod(typeof(XmlQueryOutput), "WriteNamespaceDeclarationUnchecked"); 
        public static readonly MethodInfo TextUn = GetMethod(typeof(XmlQueryOutput), "WriteStringUnchecked");
        public static readonly MethodInfo NoEntTextUn = GetMethod(typeof(XmlQueryOutput), "WriteRawUnchecked"); 
 
        public static readonly MethodInfo StartRoot = GetMethod(typeof(XmlQueryOutput), "WriteStartRoot");
        public static readonly MethodInfo EndRoot = GetMethod(typeof(XmlQueryOutput), "WriteEndRoot"); 
        public static readonly MethodInfo StartElemCopyName = GetMethod(typeof(XmlQueryOutput), "WriteStartElementComputed", typeof(XPathNavigator));
        public static readonly MethodInfo StartElemMapName = GetMethod(typeof(XmlQueryOutput), "WriteStartElementComputed", typeof(string), typeof(int));
        public static readonly MethodInfo StartElemNmspName = GetMethod(typeof(XmlQueryOutput), "WriteStartElementComputed", typeof(string), typeof(string));
        public static readonly MethodInfo StartElemQName = GetMethod(typeof(XmlQueryOutput), "WriteStartElementComputed", typeof(XmlQualifiedName)); 
        public static readonly MethodInfo StartAttrCopyName = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeComputed", typeof(XPathNavigator));
        public static readonly MethodInfo StartAttrMapName = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeComputed", typeof(string), typeof(int)); 
        public static readonly MethodInfo StartAttrNmspName = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeComputed", typeof(string), typeof(string)); 
        public static readonly MethodInfo StartAttrQName = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeComputed", typeof(XmlQualifiedName));
        public static readonly MethodInfo NamespaceDecl = GetMethod(typeof(XmlQueryOutput), "WriteNamespaceDeclaration"); 
        public static readonly MethodInfo StartComment = GetMethod(typeof(XmlQueryOutput), "WriteStartComment");
        public static readonly MethodInfo CommentText = GetMethod(typeof(XmlQueryOutput), "WriteCommentString");
        public static readonly MethodInfo EndComment = GetMethod(typeof(XmlQueryOutput), "WriteEndComment");
        public static readonly MethodInfo StartPI = GetMethod(typeof(XmlQueryOutput), "WriteStartProcessingInstruction"); 
        public static readonly MethodInfo PIText = GetMethod(typeof(XmlQueryOutput), "WriteProcessingInstructionString");
        public static readonly MethodInfo EndPI = GetMethod(typeof(XmlQueryOutput), "WriteEndProcessingInstruction"); 
        public static readonly MethodInfo WriteItem = GetMethod(typeof(XmlQueryOutput), "WriteItem"); 
        public static readonly MethodInfo CopyOf = GetMethod(typeof(XmlQueryOutput), "XsltCopyOf");
        public static readonly MethodInfo StartCopy = GetMethod(typeof(XmlQueryOutput), "StartCopy"); 
        public static readonly MethodInfo EndCopy = GetMethod(typeof(XmlQueryOutput), "EndCopy");

        // Datatypes
        public static readonly MethodInfo DecAdd = GetMethod(typeof(decimal), "Add"); 
        public static readonly MethodInfo DecCmp = GetMethod(typeof(decimal), "Compare", typeof(decimal), typeof(decimal));
        public static readonly MethodInfo DecEq = GetMethod(typeof(decimal), "Equals", typeof(decimal), typeof(decimal)); 
        public static readonly MethodInfo DecSub = GetMethod(typeof(decimal), "Subtract"); 
        public static readonly MethodInfo DecMul = GetMethod(typeof(decimal), "Multiply");
        public static readonly MethodInfo DecDiv = GetMethod(typeof(decimal), "Divide"); 
        public static readonly MethodInfo DecRem = GetMethod(typeof(decimal), "Remainder");
        public static readonly MethodInfo DecNeg = GetMethod(typeof(decimal), "Negate");
        public static readonly MethodInfo QNameEq = GetMethod(typeof(XmlQualifiedName), "Equals");
        public static readonly MethodInfo StrEq = GetMethod(typeof(string), "Equals", typeof(string), typeof(string)); 
        public static readonly MethodInfo StrCat2 = GetMethod(typeof(string), "Concat", typeof(string), typeof(string));
        public static readonly MethodInfo StrCat3 = GetMethod(typeof(string), "Concat", typeof(string), typeof(string), typeof(string)); 
        public static readonly MethodInfo StrCat4 = GetMethod(typeof(string), "Concat", typeof(string), typeof(string), typeof(string), typeof(string)); 
        public static readonly MethodInfo StrCmp = GetMethod(typeof(string), "CompareOrdinal", typeof(string), typeof(string));
        public static readonly MethodInfo StrLen = GetMethod(typeof(string), "get_Length"); 

        // XsltConvert
        public static readonly MethodInfo DblToDec = GetMethod(typeof(XsltConvert), "ToDecimal", typeof(double));
        public static readonly MethodInfo DblToInt = GetMethod(typeof(XsltConvert), "ToInt", typeof(double)); 
        public static readonly MethodInfo DblToLng = GetMethod(typeof(XsltConvert), "ToLong", typeof(double));
        public static readonly MethodInfo DblToStr = GetMethod(typeof(XsltConvert), "ToString", typeof(double)); 
        public static readonly MethodInfo DecToDbl = GetMethod(typeof(XsltConvert), "ToDouble", typeof(decimal)); 
        public static readonly MethodInfo DTToStr = GetMethod(typeof(XsltConvert), "ToString", typeof(DateTime));
        public static readonly MethodInfo IntToDbl = GetMethod(typeof(XsltConvert), "ToDouble", typeof(int)); 
        public static readonly MethodInfo LngToDbl = GetMethod(typeof(XsltConvert), "ToDouble", typeof(long));
        public static readonly MethodInfo StrToDbl = GetMethod(typeof(XsltConvert), "ToDouble", typeof(string));
        public static readonly MethodInfo StrToDT = GetMethod(typeof(XsltConvert), "ToDateTime", typeof(string));
 
        public static readonly MethodInfo ItemToBool = GetMethod(typeof(XsltConvert), "ToBoolean", typeof(XPathItem));
        public static readonly MethodInfo ItemToDbl = GetMethod(typeof(XsltConvert), "ToDouble", typeof(XPathItem)); 
        public static readonly MethodInfo ItemToStr = GetMethod(typeof(XsltConvert), "ToString", typeof(XPathItem)); 
        public static readonly MethodInfo ItemToNode = GetMethod(typeof(XsltConvert), "ToNode", typeof(XPathItem));
        public static readonly MethodInfo ItemToNodes = GetMethod(typeof(XsltConvert), "ToNodeSet", typeof(XPathItem)); 

        public static readonly MethodInfo ItemsToBool = GetMethod(typeof(XsltConvert), "ToBoolean", typeof(IList));
        public static readonly MethodInfo ItemsToDbl = GetMethod(typeof(XsltConvert), "ToDouble", typeof(IList));
        public static readonly MethodInfo ItemsToNode = GetMethod(typeof(XsltConvert), "ToNode", typeof(IList)); 
        public static readonly MethodInfo ItemsToNodes = GetMethod(typeof(XsltConvert), "ToNodeSet", typeof(IList));
        public static readonly MethodInfo ItemsToStr = GetMethod(typeof(XsltConvert), "ToString", typeof(IList)); 
 
        // StringConcat
        public static readonly MethodInfo StrCatCat = GetMethod(typeof(StringConcat), "Concat"); 
        public static readonly MethodInfo StrCatClear = GetMethod(typeof(StringConcat), "Clear");
        public static readonly MethodInfo StrCatResult = GetMethod(typeof(StringConcat), "GetResult");
        public static readonly MethodInfo StrCatDelim = GetMethod(typeof(StringConcat), "set_Delimiter");
 
        // XmlILStorageConverter
        public static readonly MethodInfo NavsToItems = GetMethod(typeof(XmlILStorageConverter), "NavigatorsToItems"); 
        public static readonly MethodInfo ItemsToNavs = GetMethod(typeof(XmlILStorageConverter), "ItemsToNavigators"); 

        // XmlQueryNodeSequence 
        public static readonly MethodInfo SetDod = GetMethod(typeof(XmlQueryNodeSequence), "set_IsDocOrderDistinct");

        // Miscellaneous
        public static readonly MethodInfo GetTypeFromHandle = GetMethod(typeof(Type), "GetTypeFromHandle"); 
        public static readonly MethodInfo InitializeArray = GetMethod(typeof(System.Runtime.CompilerServices.RuntimeHelpers), "InitializeArray");
        public static readonly Dictionary StorageMethods; 
 
        static XmlILMethods() {
            StorageMethods = new Dictionary(); 
            StorageMethods[typeof(string)] = new XmlILStorageMethods(typeof(string));
            StorageMethods[typeof(bool)] = new XmlILStorageMethods(typeof(bool));
            StorageMethods[typeof(int)] = new XmlILStorageMethods(typeof(int));
            StorageMethods[typeof(long)] = new XmlILStorageMethods(typeof(long)); 
            StorageMethods[typeof(decimal)] = new XmlILStorageMethods(typeof(decimal));
            StorageMethods[typeof(double)] = new XmlILStorageMethods(typeof(double)); 
            StorageMethods[typeof(float)] = new XmlILStorageMethods(typeof(float)); 
            StorageMethods[typeof(DateTime)] = new XmlILStorageMethods(typeof(DateTime));
            StorageMethods[typeof(byte[])] = new XmlILStorageMethods(typeof(byte[])); 
            StorageMethods[typeof(XmlQualifiedName)] = new XmlILStorageMethods(typeof(XmlQualifiedName));
            StorageMethods[typeof(TimeSpan)] = new XmlILStorageMethods(typeof(TimeSpan));
            StorageMethods[typeof(XPathItem)] = new XmlILStorageMethods(typeof(XPathItem));
            StorageMethods[typeof(XPathNavigator)] = new XmlILStorageMethods(typeof(XPathNavigator)); 
        }
 
        public static MethodInfo GetMethod(Type className, string methName) { 
            MethodInfo methInfo = className.GetMethod(methName);
            Debug.Assert(methInfo != null, "Method " + className.Name + "." + methName + " cannot be null."); 
            return methInfo;
        }

        public static MethodInfo GetMethod(Type className, string methName, params Type[] args) { 
            MethodInfo methInfo = className.GetMethod(methName, args);
            Debug.Assert(methInfo != null, "Method " + methName + " cannot be null."); 
            return methInfo; 
        }
    } 


    /// 
    /// When named nodes are constructed, there are several possible ways for their names to be created. 
    /// 
    internal enum GenerateNameType { 
        LiteralLocalName,       // Local name is a literal string; namespace is null 
        LiteralName,            // All parts of the name are literal strings
        CopiedName,             // Name should be copied from a navigator 
        TagNameAndMappings,     // Tagname contains prefix:localName and prefix is mapped to a namespace
        TagNameAndNamespace,    // Tagname contains prefix:localName and namespace is provided
        QName,                  // Name is computed QName (no prefix available)
        StackName,              // Element name has already been pushed onto XmlQueryOutput stack 
    }
 
    ///  
    /// Contains helper methods used during the code generation phase.
    ///  
    internal class GenerateHelper {
        private MethodBase methInfo;
        private ILGenerator ilgen;
        private LocalBuilder locXOut; 
        private XmlILModule module;
        private bool isDebug, initWriters; 
        private StaticDataManager staticData; 
        private ISourceLineInfo lastSourceInfo;
        private MethodInfo methSyncToNav; 

    #if DEBUG
        private int lblNum;
        private Hashtable symbols; 
        private int numLocals;
        private string sourceFile; 
        private TextWriter writerDump; 
    #endif
 
        /// 
        /// Cache metadata used during code-generation phase.
        /// 
        public GenerateHelper(XmlILModule module, bool isDebug) { 
            this.isDebug = isDebug;
            this.module = module; 
            this.staticData = new StaticDataManager(); 

        #if DEBUG 
            if (XmlILTrace.IsEnabled)
                XmlILTrace.PrepareTraceWriter("dump.il");
        #endif
        } 

        ///  
        /// Begin generating code within a new method. 
        /// 
        public void MethodBegin(MethodBase methInfo, ISourceLineInfo sourceInfo, bool initWriters) { 
            this.methInfo = methInfo;
            this.ilgen = XmlILModule.DefineMethodBody(methInfo);
            this.lastSourceInfo = null;
 
        #if DEBUG
            if (XmlILTrace.IsEnabled) { 
                this.numLocals = 0; 
                this.symbols = new Hashtable();
                this.lblNum = 0; 
                this.sourceFile = null;

                this.writerDump = XmlILTrace.GetTraceWriter("dump.il");
                this.writerDump.WriteLine(".method {0}()", methInfo.Name); 
                this.writerDump.WriteLine("{");
            } 
        #endif 

            if (this.isDebug) { 
                DebugStartScope();

                // DebugInfo: Sequence point just before generating code for this function
                if (sourceInfo != null) { 
                    // Don't call DebugSequencePoint, as it puts Nop *before* the sequence point.  That is
                    // wrong in this case, because we need source line information to be emitted before any 
                    // IL instruction so that stepping into this function won't end up in the assembly window. 
                    // We still guarantee that:
                    //   1. Two sequence points are never adjacent, since this is the 1st sequence point 
                    //   2. Stack depth is 0, since this is the very beginning of the method
                    MarkSequencePoint(sourceInfo);
                    Emit(OpCodes.Nop);
                } 
            }
 
            this.initWriters = false; 
            if (initWriters) {
                EnsureWriter(); 
                LoadQueryRuntime();
                Call(XmlILMethods.GetOutput);
                Emit(OpCodes.Stloc, this.locXOut);
            } 
        }
 
        ///  
        /// Generate "ret" instruction and branch fixup jump table.
        ///  
        public void MethodEnd() {
            Emit(OpCodes.Ret);

        #if DEBUG 
            if (XmlILTrace.IsEnabled) {
                this.writerDump.WriteLine("}"); 
                this.writerDump.WriteLine(""); 
                this.writerDump.Close();
            } 
        #endif

            if (this.isDebug)
                DebugEndScope(); 
        }
 
 
        //-----------------------------------------------
        // Helper Global Methods 
        //-----------------------------------------------

        /// 
        /// Call a static method which attempts to reuse a navigator. 
        /// 
        public void CallSyncToNavigator() { 
            // Get helper method from module 
            if (this.methSyncToNav == null)
                this.methSyncToNav = this.module.FindMethod("SyncToNavigator"); 

            Call(this.methSyncToNav);
        }
 
        //-----------------------------------------------
        // StaticDataManager 
        //----------------------------------------------- 

        ///  
        /// This internal class manages literal names, literal types, and storage for global variables.
        /// 
        public StaticDataManager StaticData {
            get { return this.staticData; } 
        }
 
 
        //-----------------------------------------------
        // Constants 
        //-----------------------------------------------

        /// 
        /// Generate the optimal Ldc_I4 instruction based on intVal. 
        /// 
        public void LoadInteger(int intVal) { 
            OpCode opcode; 

            if (intVal >= -1 && intVal < 9) { 
                switch (intVal) {
                    case -1: opcode = OpCodes.Ldc_I4_M1; break;
                    case 0: opcode = OpCodes.Ldc_I4_0; break;
                    case 1: opcode = OpCodes.Ldc_I4_1; break; 
                    case 2: opcode = OpCodes.Ldc_I4_2; break;
                    case 3: opcode = OpCodes.Ldc_I4_3; break; 
                    case 4: opcode = OpCodes.Ldc_I4_4; break; 
                    case 5: opcode = OpCodes.Ldc_I4_5; break;
                    case 6: opcode = OpCodes.Ldc_I4_6; break; 
                    case 7: opcode = OpCodes.Ldc_I4_7; break;
                    case 8: opcode = OpCodes.Ldc_I4_8; break;
                    default: Debug.Assert(false); return;
                } 
                Emit(opcode);
            } 
            else if (intVal >= -128 && intVal <= 127) 
                Emit(OpCodes.Ldc_I4_S, (sbyte) intVal);
            else 
                Emit(OpCodes.Ldc_I4, intVal);
        }

        public void LoadBoolean(bool boolVal) { 
            Emit(boolVal ? OpCodes.Ldc_I4_1 : OpCodes.Ldc_I4_0);
        } 
 
        public void LoadType(Type clrTyp) {
            Emit(OpCodes.Ldtoken, clrTyp); 
            Call(XmlILMethods.GetTypeFromHandle);
        }

 
        //-----------------------------------------------
        // Local variables 
        //----------------------------------------------- 

        ///  
        /// Generate a new local variable.  Add a numeric suffix to name that ensures that all
        /// local variable names will be unique (for readability).
        /// 
        public LocalBuilder DeclareLocal(string name, Type type) { 
            LocalBuilder locBldr = this.ilgen.DeclareLocal(type);
        #if DEBUG 
            if (XmlILTrace.IsEnabled) { 
                // Set name for internal MS debugging.  This is not the user-defined name--that will be set later
                if (this.isDebug) 
                    locBldr.SetLocalSymInfo(name + this.numLocals.ToString(CultureInfo.InvariantCulture));

                this.symbols.Add(locBldr, name + this.numLocals.ToString(CultureInfo.InvariantCulture));
                this.numLocals++; 
            }
        #endif 
            return locBldr; 
        }
 
        public void LoadQueryRuntime() {
            Emit(OpCodes.Ldarg_0);
        }
 
        public void LoadQueryContext() {
            Emit(OpCodes.Ldarg_0); 
            Call(XmlILMethods.Context); 
        }
 
        public void LoadXsltLibrary() {
            Emit(OpCodes.Ldarg_0);
            Call(XmlILMethods.XsltLib);
        } 

        public void LoadQueryOutput() { 
            Emit(OpCodes.Ldloc, this.locXOut); 
        }
 

        //-----------------------------------------------
        // Parameters
        //----------------------------------------------- 

        public void LoadParameter(int paramPos) { 
            switch (paramPos) { 
                case 0: Emit(OpCodes.Ldarg_0); break;
                case 1: Emit(OpCodes.Ldarg_1); break; 
                case 2: Emit(OpCodes.Ldarg_2); break;
                case 3: Emit(OpCodes.Ldarg_3); break;
                default:
                    if (paramPos <= 255) { 
                        Emit(OpCodes.Ldarg_S, (byte) paramPos);
                    } 
                    else if (paramPos <= ushort.MaxValue) { 
                        Emit(OpCodes.Ldarg, paramPos);
                    } 
                    else {
                        throw new XslTransformException(Res.XmlIl_TooManyParameters);
                    }
                    break; 
            }
        } 
 
        public void SetParameter(object paramId) {
            int paramPos = (int) paramId; 

            if (paramPos <= 255) {
                Emit(OpCodes.Starg_S, (byte) paramPos);
            } 
            else if (paramPos <= ushort.MaxValue) {
                Emit(OpCodes.Starg, (int) paramPos); 
            } 
            else {
                throw new XslTransformException(Res.XmlIl_TooManyParameters); 
            }
        }

        //----------------------------------------------- 
        // Labels
        //----------------------------------------------- 
 
        /// 
        /// Branch to lblBranch and anchor lblMark.  If lblBranch = lblMark, then no need 
        /// to generate a "br" to the next instruction.
        /// 
        public void BranchAndMark(Label lblBranch, Label lblMark) {
            if (!lblBranch.Equals(lblMark)) { 
                EmitUnconditionalBranch(OpCodes.Br, lblBranch);
            } 
            MarkLabel(lblMark); 
        }
 

        //-----------------------------------------------
        // Comparison
        //----------------------------------------------- 

        ///  
        /// Compare the top value on the stack with the specified i4 using the specified relational 
        /// comparison opcode, and branch to lblBranch if the result is true.
        ///  
        public void TestAndBranch(int i4, Label lblBranch, OpCode opcodeBranch) {
            switch (i4) {
                case 0:
                    // Beq or Bne can be shortened to Brfalse or Brtrue if comparing to 0 
                    if (opcodeBranch.Value == OpCodes.Beq.Value)
                        opcodeBranch = OpCodes.Brfalse; 
                    else if (opcodeBranch.Value == OpCodes.Beq_S.Value) 
                        opcodeBranch = OpCodes.Brfalse_S;
                    else if (opcodeBranch.Value == OpCodes.Bne_Un.Value) 
                        opcodeBranch = OpCodes.Brtrue;
                    else if (opcodeBranch.Value == OpCodes.Bne_Un_S.Value)
                        opcodeBranch = OpCodes.Brtrue_S;
                    else 
                        goto default;
                    break; 
 
                default:
                    // Cannot use shortcut, so push integer onto the stack 
                    LoadInteger(i4);
                    break;
            }
 
            Emit(opcodeBranch, lblBranch);
        } 
 
        /// 
        /// Assume a branch instruction has already been issued.  If isTrueBranch is true, then the 
        /// true path is linked to lblBranch.  Otherwise, the false path is linked to lblBranch.
        /// Convert this "branching" boolean logic into an explicit push of 1 or 0 onto the stack.
        /// 
        public void ConvBranchToBool(Label lblBranch, bool isTrueBranch) { 
            Label lblDone = DefineLabel();
 
            Emit(isTrueBranch ? OpCodes.Ldc_I4_0 : OpCodes.Ldc_I4_1); 
            EmitUnconditionalBranch(OpCodes.Br_S, lblDone);
            MarkLabel(lblBranch); 
            Emit(isTrueBranch ? OpCodes.Ldc_I4_1 : OpCodes.Ldc_I4_0);
            MarkLabel(lblDone);
        }
 

        //----------------------------------------------- 
        // Frequently used method and function calls 
        //-----------------------------------------------
 
        public void TailCall(MethodInfo meth) {
            Emit(OpCodes.Tailcall);
            Call(meth);
            Emit(OpCodes.Ret); 
        }
 
        [Conditional("DEBUG")] 
        private void TraceCall(OpCode opcode, MethodInfo meth) {
        #if DEBUG 
            if (XmlILTrace.IsEnabled) {
                StringBuilder strBldr = new StringBuilder();
                bool isFirst = true;
                string retType = ""; 

                if (!(meth is MethodBuilder)) { 
                    foreach (ParameterInfo paramInfo in meth.GetParameters()) { 
                        if (isFirst)
                            isFirst = false; 
                        else
                            strBldr.Append(", ");
                        strBldr.Append(paramInfo.ParameterType.Name);
                    } 
                    retType = meth.ReturnType.Name;
                } 
 
                this.writerDump.WriteLine("  {0, -10} {1} {2}({3})", new object[] {opcode.Name, retType, meth.Name, strBldr.ToString()});
            } 
        #endif
        }

        public void Call(MethodInfo meth) { 
            OpCode opcode = meth.IsVirtual || meth.IsAbstract ? OpCodes.Callvirt : OpCodes.Call;
 
            TraceCall(opcode, meth); 
            this.ilgen.Emit(opcode, meth);
 
            if (this.lastSourceInfo != null) {
                // Emit a "no source" sequence point, otherwise the debugger would return to the wrong line
                // once the call has finished.  We are guaranteed not to emit adjacent sequence points because
                // the Call instruction precedes this sequence point, and a nop instruction precedes other 
                // sequence points.
                MarkSequencePoint(SourceLineInfo.NoSource); 
            } 
        }
 
        //
        public void CallToken(MethodInfo meth) {
            Debug.Assert(!(methInfo is ConstructorBuilder));
            MethodBuilder methBldr = this.methInfo as MethodBuilder; 

            if (methBldr != null) { 
                // Using regular reflection emit, so get a token for the specified method. 
                // The token is only valid within scope of this method's body.
                OpCode opcode = meth.IsVirtual || meth.IsAbstract ? OpCodes.Callvirt : OpCodes.Call; 

                TraceCall(opcode, meth);
                this.ilgen.Emit(opcode, ((ModuleBuilder) methBldr.GetModule()).GetMethodToken(meth).Token);
 
                if (this.lastSourceInfo != null) {
                    // Emit a "no source" sequence point, otherwise the debugger would return to the wrong line 
                    // once the call has finished.  We are guaranteed not to emit adjacent sequence points because 
                    // the Call instruction precedes this sequence point, and a nop instruction precedes other
                    // sequence points. 
                    MarkSequencePoint(SourceLineInfo.NoSource);
                }
            }
            else { 
                // Using LCG, so no need to workaround
                Call(meth); 
            } 
        }
 
        public void Construct(ConstructorInfo constr) {
            Emit(OpCodes.Newobj, constr);
        }
 
        public void CallConcatStrings(int cStrings) {
            switch (cStrings) { 
                case 0: 
                    Emit(OpCodes.Ldstr, "");
                    break; 
                case 1:
                    break;
                case 2:
                    Call(XmlILMethods.StrCat2); 
                    break;
                case 3: 
                    Call(XmlILMethods.StrCat3); 
                    break;
                case 4: 
                    Call(XmlILMethods.StrCat4);
                    break;
                default:
                    Debug.Assert(false, "Shouldn't be called"); 
                    break;
            } 
        } 

        ///  
        /// Assume that an object reference is on the IL stack.  Change the static Clr type from "clrTypeSrc" to "clrTypeDst"
        /// 
        public void TreatAs(Type clrTypeSrc, Type clrTypeDst) {
            // If source = destination, then no-op 
            if (clrTypeSrc == clrTypeDst)
                return; 
 
            if (clrTypeSrc.IsValueType) {
                // If source is a value type, then destination may only be typeof(object), so box 
                Debug.Assert(clrTypeDst == typeof(object), "Invalid cast, since value types do not allow inheritance.");
                Emit(OpCodes.Box, clrTypeSrc);
            }
            else if (clrTypeDst.IsValueType) { 
                // If destination type is value type, then source may only be typeof(object), so unbox
                Debug.Assert(clrTypeSrc == typeof(object), "Invalid cast, since value types do not allow inheritance."); 
                Emit(OpCodes.Unbox, clrTypeDst); 
                Emit(OpCodes.Ldobj, clrTypeDst);
            } 
            else if (clrTypeDst != typeof(object)) {
                // If source is not a value type, and destination type is typeof(object), then no-op
                // Otherwise, use Castclass to change the static type
                Debug.Assert(clrTypeSrc.IsAssignableFrom(clrTypeDst) || clrTypeDst.IsAssignableFrom(clrTypeSrc), 
                             "Invalid cast, since source type and destination type are not in same inheritance hierarchy.");
                Emit(OpCodes.Castclass, clrTypeDst); 
            } 
        }
 

        //-----------------------------------------------
        // Datatype methods
        //----------------------------------------------- 

        public void ConstructLiteralDecimal(decimal dec) { 
            if (dec >= (decimal) int.MinValue && dec <= (decimal) int.MaxValue && decimal.Truncate(dec) == dec) { 
                // Decimal can be constructed from a 32-bit integer
                LoadInteger((int) dec); 
                Construct(XmlILConstructors.DecFromInt32);
            }
            else {
                int[] bits = Decimal.GetBits(dec); 

                LoadInteger(bits[0]); 
                LoadInteger(bits[1]); 
                LoadInteger(bits[2]);
                LoadBoolean(bits[3] < 0); 
                LoadInteger(bits[3] >> 16);
                Construct(XmlILConstructors.DecFromParts);
            }
        } 

        public void ConstructLiteralQName(string localName, string namespaceName) { 
            Emit(OpCodes.Ldstr, localName); 
            Emit(OpCodes.Ldstr, namespaceName);
            Construct(XmlILConstructors.QName); 
        }

        public void CallArithmeticOp(QilNodeType opType, XmlTypeCode code) {
            MethodInfo meth = null; 

            switch (code) { 
                case XmlTypeCode.Int: 
                case XmlTypeCode.Integer:
                case XmlTypeCode.Double: 
                case XmlTypeCode.Float:
                    switch (opType) {
                        case QilNodeType.Add: Emit(OpCodes.Add); break;
                        case QilNodeType.Subtract: Emit(OpCodes.Sub); break; 
                        case QilNodeType.Multiply: Emit(OpCodes.Mul); break;
                        case QilNodeType.Divide: Emit(OpCodes.Div); break; 
                        case QilNodeType.Modulo: Emit(OpCodes.Rem); break; 
                        case QilNodeType.Negate: Emit(OpCodes.Neg); break;
                        default: Debug.Assert(false, opType + " must be an arithmetic operation."); break; 
                    }
                    break;

                case XmlTypeCode.Decimal: 
                    switch (opType) {
                        case QilNodeType.Add: meth = XmlILMethods.DecAdd; break; 
                        case QilNodeType.Subtract: meth = XmlILMethods.DecSub; break; 
                        case QilNodeType.Multiply: meth = XmlILMethods.DecMul; break;
                        case QilNodeType.Divide: meth = XmlILMethods.DecDiv; break; 
                        case QilNodeType.Modulo: meth = XmlILMethods.DecRem; break;
                        case QilNodeType.Negate: meth = XmlILMethods.DecNeg; break;
                        default: Debug.Assert(false, opType + " must be an arithmetic operation."); break;
                    } 

                    Call(meth); 
                    break; 

                default: 
                    Debug.Assert(false, "The " + opType + " arithmetic operation cannot be performed on values of type " + code + ".");
                    break;
            }
        } 

        public void CallCompareEquals(XmlTypeCode code) { 
            MethodInfo meth = null; 

            switch (code) { 
                case XmlTypeCode.String: meth = XmlILMethods.StrEq; break;
                case XmlTypeCode.QName: meth = XmlILMethods.QNameEq; break;
                case XmlTypeCode.Decimal: meth = XmlILMethods.DecEq; break;
                default: 
                    Debug.Assert(false, "Type " + code + " does not support the equals operation.");
                    break; 
            } 

            Call(meth); 
        }

        public void CallCompare(XmlTypeCode code) {
            MethodInfo meth = null; 

            switch (code) { 
                case XmlTypeCode.String: meth = XmlILMethods.StrCmp; break; 
                case XmlTypeCode.Decimal: meth = XmlILMethods.DecCmp; break;
                default: 
                    Debug.Assert(false, "Type " + code + " does not support the equals operation.");
                    break;
            }
 
            Call(meth);
        } 
 

        //----------------------------------------------- 
        // XmlQueryRuntime function calls
        //-----------------------------------------------

        public void CallStartRtfConstruction(string baseUri) { 
            EnsureWriter();
            LoadQueryRuntime(); 
            Emit(OpCodes.Ldstr, baseUri); 
            Emit(OpCodes.Ldloca, this.locXOut);
            Call(XmlILMethods.StartRtfConstr); 
        }

        public void CallEndRtfConstruction() {
            LoadQueryRuntime(); 
            Emit(OpCodes.Ldloca, this.locXOut);
            Call(XmlILMethods.EndRtfConstr); 
        } 

        public void CallStartSequenceConstruction() { 
            EnsureWriter();
            LoadQueryRuntime();
            Emit(OpCodes.Ldloca, this.locXOut);
            Call(XmlILMethods.StartSeqConstr); 
        }
 
        public void CallEndSequenceConstruction() { 
            LoadQueryRuntime();
            Emit(OpCodes.Ldloca, this.locXOut); 
            Call(XmlILMethods.EndSeqConstr);
        }

        public void CallGetEarlyBoundObject(int idxObj, Type clrType) { 
            LoadQueryRuntime();
            LoadInteger(idxObj); 
            Call(XmlILMethods.GetEarly); 
            TreatAs(typeof(object), clrType);
        } 

        public void CallGetAtomizedName(int idxName) {
            LoadQueryRuntime();
            LoadInteger(idxName); 
            Call(XmlILMethods.GetAtomizedName);
        } 
 
        public void CallGetNameFilter(int idxFilter) {
            LoadQueryRuntime(); 
            LoadInteger(idxFilter);
            Call(XmlILMethods.GetNameFilter);
        }
 
        public void CallGetTypeFilter(XPathNodeType nodeType) {
            LoadQueryRuntime(); 
            LoadInteger((int) nodeType); 
            Call(XmlILMethods.GetTypeFilter);
        } 

        public void CallParseTagName(GenerateNameType nameType) {
            if (nameType == GenerateNameType.TagNameAndMappings) {
                Call(XmlILMethods.TagAndMappings); 
            }
            else { 
                Debug.Assert(nameType == GenerateNameType.TagNameAndNamespace); 
                Call(XmlILMethods.TagAndNamespace);
            } 
        }

        public void CallGetGlobalValue(int idxValue, Type clrType) {
            LoadQueryRuntime(); 
            LoadInteger(idxValue);
            Call(XmlILMethods.GetGlobalValue); 
            TreatAs(typeof(object), clrType); 
        }
 
        public void CallSetGlobalValue(Type clrType) {
            TreatAs(clrType, typeof(object));
            Call(XmlILMethods.SetGlobalValue);
        } 

        public void CallGetCollation(int idxName) { 
            LoadQueryRuntime(); 
            LoadInteger(idxName);
            Call(XmlILMethods.GetCollation); 
        }

        private void EnsureWriter() {
            // If write variable has not yet been initialized, do it now 
            if (!this.initWriters) {
                this.locXOut = DeclareLocal("$$$xwrtChk", typeof(XmlQueryOutput)); 
                this.initWriters = true; 
            }
        } 


        //-----------------------------------------------
        // XmlQueryContext function calls 
        //-----------------------------------------------
 
        public void CallGetParameter(string localName, string namespaceUri) { 
            LoadQueryContext();
            Emit(OpCodes.Ldstr, localName); 
            Emit(OpCodes.Ldstr, namespaceUri);
            Call(XmlILMethods.GetParam);
        }
 
        //-----------------------------------------------
        // XmlQueryOutput function calls 
        //----------------------------------------------- 

        public void CallStartTree(XPathNodeType rootType) { 
            LoadQueryOutput();
            LoadInteger((int) rootType);
            Call(XmlILMethods.StartTree);
        } 

        public void CallEndTree() { 
            LoadQueryOutput(); 
            Call(XmlILMethods.EndTree);
        } 

        public void CallWriteStartRoot() {
            // Call XmlQueryOutput.WriteStartRoot
            LoadQueryOutput(); 
            Call(XmlILMethods.StartRoot);
        } 
 
        public void CallWriteEndRoot() {
            // Call XmlQueryOutput.WriteEndRoot 
            LoadQueryOutput();
            Call(XmlILMethods.EndRoot);
        }
 
        public void CallWriteStartElement(GenerateNameType nameType, bool callChk) {
            MethodInfo meth = null; 
 
            // If runtime checks need to be made,
            if (callChk) { 
                // Then call XmlQueryOutput.WriteStartElement
                switch (nameType) {
                    case GenerateNameType.LiteralLocalName: meth = XmlILMethods.StartElemLocName; break;
                    case GenerateNameType.LiteralName: meth = XmlILMethods.StartElemLitName; break; 
                    case GenerateNameType.CopiedName: meth = XmlILMethods.StartElemCopyName; break;
                    case GenerateNameType.TagNameAndMappings: meth = XmlILMethods.StartElemMapName; break; 
                    case GenerateNameType.TagNameAndNamespace: meth = XmlILMethods.StartElemNmspName; break; 
                    case GenerateNameType.QName: meth = XmlILMethods.StartElemQName; break;
                    default: Debug.Assert(false, nameType + " is invalid here."); break; 
                }
            }
            else {
                // Else call XmlQueryOutput.WriteStartElementUnchecked 
                switch (nameType) {
                    case GenerateNameType.LiteralLocalName: meth = XmlILMethods.StartElemLocNameUn; break; 
                    case GenerateNameType.LiteralName: meth = XmlILMethods.StartElemLitNameUn; break; 
                    default: Debug.Assert(false, nameType + " is invalid here."); break;
                } 
            }

            Call(meth);
        } 

        public void CallWriteEndElement(GenerateNameType nameType, bool callChk) { 
            MethodInfo meth = null; 

            // If runtime checks need to be made, 
            if (callChk) {
                // Then call XmlQueryOutput.WriteEndElement
                meth = XmlILMethods.EndElemStackName;
            } 
            else {
                // Else call XmlQueryOutput.WriteEndElementUnchecked 
                switch (nameType) { 
                    case GenerateNameType.LiteralLocalName: meth = XmlILMethods.EndElemLocNameUn; break;
                    case GenerateNameType.LiteralName: meth = XmlILMethods.EndElemLitNameUn; break; 
                    default: Debug.Assert(false, nameType + " is invalid here."); break;
                }
            }
 
            Call(meth);
        } 
 
        public void CallStartElementContent() {
            LoadQueryOutput(); 
            Call(XmlILMethods.StartContentUn);
        }

        public void CallWriteStartAttribute(GenerateNameType nameType, bool callChk) { 
            MethodInfo meth = null;
 
            // If runtime checks need to be made, 
            if (callChk) {
                // Then call XmlQueryOutput.WriteStartAttribute 
                switch (nameType) {
                    case GenerateNameType.LiteralLocalName: meth = XmlILMethods.StartAttrLocName; break;
                    case GenerateNameType.LiteralName: meth = XmlILMethods.StartAttrLitName; break;
                    case GenerateNameType.CopiedName: meth = XmlILMethods.StartAttrCopyName; break; 
                    case GenerateNameType.TagNameAndMappings: meth = XmlILMethods.StartAttrMapName; break;
                    case GenerateNameType.TagNameAndNamespace: meth = XmlILMethods.StartAttrNmspName; break; 
                    case GenerateNameType.QName: meth = XmlILMethods.StartAttrQName; break; 
                    default: Debug.Assert(false, nameType + " is invalid here."); break;
                } 
            }
            else {
                // Else call XmlQueryOutput.WriteStartAttributeUnchecked
                switch (nameType) { 
                    case GenerateNameType.LiteralLocalName: meth = XmlILMethods.StartAttrLocNameUn; break;
                    case GenerateNameType.LiteralName: meth = XmlILMethods.StartAttrLitNameUn; break; 
                    default: Debug.Assert(false, nameType + " is invalid here."); break; 
                }
            } 

            Call(meth);
        }
 
        public void CallWriteEndAttribute(bool callChk) {
            LoadQueryOutput(); 
 
            // If runtime checks need to be made,
            if (callChk) { 
                // Then call XmlQueryOutput.WriteEndAttribute
                Call(XmlILMethods.EndAttr);
            }
            else { 
                // Else call XmlQueryOutput.WriteEndAttributeUnchecked
                Call(XmlILMethods.EndAttrUn); 
            } 
        }
 
        public void CallWriteNamespaceDecl(bool callChk) {
            // If runtime checks need to be made,
            if (callChk) {
                // Then call XmlQueryOutput.WriteNamespaceDeclaration 
                Call(XmlILMethods.NamespaceDecl);
            } 
            else { 
                // Else call XmlQueryOutput.WriteNamespaceDeclarationUnchecked
                Call(XmlILMethods.NamespaceDeclUn); 
            }
        }

        public void CallWriteString(bool disableOutputEscaping, bool callChk) { 
            // If runtime checks need to be made,
            if (callChk) { 
                // Then call XmlQueryOutput.WriteString, or XmlQueryOutput.WriteRaw 
                if (disableOutputEscaping)
                    Call(XmlILMethods.NoEntText); 
                else
                    Call(XmlILMethods.Text);
            }
            else { 
                // Else call XmlQueryOutput.WriteStringUnchecked, or XmlQueryOutput.WriteRawUnchecked
                if (disableOutputEscaping) 
                    Call(XmlILMethods.NoEntTextUn); 
                else
                    Call(XmlILMethods.TextUn); 
            }
        }

        public void CallWriteStartPI() { 
            Call(XmlILMethods.StartPI);
        } 
 
        public void CallWriteEndPI() {
            LoadQueryOutput(); 
            Call(XmlILMethods.EndPI);
        }

        public void CallWriteStartComment() { 
            LoadQueryOutput();
            Call(XmlILMethods.StartComment); 
        } 

        public void CallWriteEndComment() { 
            LoadQueryOutput();
            Call(XmlILMethods.EndComment);
        }
 

        //----------------------------------------------- 
        // Item caching methods 
        //-----------------------------------------------
 
        public void CallCacheCount(Type itemStorageType) {
            XmlILStorageMethods meth = XmlILMethods.StorageMethods[itemStorageType];
            Call(meth.IListCount);
        } 

        public void CallCacheItem(Type itemStorageType) { 
            Call(XmlILMethods.StorageMethods[itemStorageType].IListItem); 
        }
 

        //-----------------------------------------------
        // XPathItem properties and methods
        //----------------------------------------------- 

        public void CallValueAs(Type clrType) { 
            MethodInfo meth; 

            meth = XmlILMethods.StorageMethods[clrType].ValueAs; 
            if (meth == null) {
                // Call (Type) item.ValueAs(Type, null)
                LoadType(clrType);
                Emit(OpCodes.Ldnull); 
                Call(XmlILMethods.ValueAsAny);
 
                // Unbox or down-cast 
                TreatAs(typeof(object), clrType);
            } 
            else {
                // Call strongly typed ValueAs method
                Call(meth);
            } 
        }
 
 
        //-----------------------------------------------
        // XmlSortKeyAccumulator methods 
        //-----------------------------------------------

        public void AddSortKey(XmlQueryType keyType) {
            MethodInfo meth = null; 

            if (keyType == null) { 
                meth = XmlILMethods.SortKeyEmpty; 
            }
            else { 
                Debug.Assert(keyType.IsAtomicValue, "Sort key must have atomic value type.");

                switch (keyType.TypeCode) {
                    case XmlTypeCode.String: meth = XmlILMethods.SortKeyString; break; 
                    case XmlTypeCode.Decimal: meth = XmlILMethods.SortKeyDecimal; break;
                    case XmlTypeCode.Integer: meth = XmlILMethods.SortKeyInteger; break; 
                    case XmlTypeCode.Int: meth = XmlILMethods.SortKeyInt; break; 
                    case XmlTypeCode.Boolean: meth = XmlILMethods.SortKeyInt; break;
                    case XmlTypeCode.Double: meth = XmlILMethods.SortKeyDouble; break; 
                    case XmlTypeCode.DateTime: meth = XmlILMethods.SortKeyDateTime; break;

                    case XmlTypeCode.None:
                        // Empty sequence, so this path will never actually be taken 
                        Emit(OpCodes.Pop);
                        meth = XmlILMethods.SortKeyEmpty; 
                        break; 

                    case XmlTypeCode.AnyAtomicType: 
                        Debug.Assert(false, "Heterogenous sort key is not allowed.");
                        return;

                    default: 
                        Debug.Assert(false, "Sorting over datatype " + keyType.TypeCode + " is not allowed.");
                        break; 
                } 
            }
 
            Call(meth);
        }

 
        //-----------------------------------------------
        // Debugging information output 
        //----------------------------------------------- 

        ///  
        /// Begin a new variable debugging scope.
        /// 
        public void DebugStartScope() {
            this.ilgen.BeginScope(); 
        }
 
        ///  
        /// End a new debugging scope.
        ///  
        public void DebugEndScope() {
            this.ilgen.EndScope();
        }
 
        /// 
        /// Correlate the current IL generation position with the current source position. 
        ///  
        public void DebugSequencePoint(ISourceLineInfo sourceInfo) {
            Debug.Assert(this.isDebug && this.lastSourceInfo != null); 
            Debug.Assert(sourceInfo != null);

            // When emitting sequence points, be careful to always follow two rules:
            // 1. Never emit adjacent sequence points, as this messes up the debugger.  We guarantee this by 
            //    always emitting a Nop before every sequence point.
            // 2. The runtime enforces a rule that BP sequence points can only appear at zero stack depth, 
            //    or if a NOP instruction is placed before them.  We guarantee this by always emitting a Nop 
            //    before every sequence point.
            //    http://devdiv/Documents/Whidbey/CLR/CurrentSpecs/Debugging%20and%20Profiling/JIT-Determined%20Sequence%20Points.doc 
            Emit(OpCodes.Nop);
            MarkSequencePoint(sourceInfo);
        }
 
        private string  lastUriString = null;
        private string  lastFileName  = null; 
 
        // SQLBUDT 278010: debugger does not work with network paths in uri format, like file://server/share/dir/file
        private string GetFileName(ISourceLineInfo sourceInfo) { 
            string uriString = sourceInfo.Uri;
            if ((object)uriString == (object)lastUriString) {
                return lastFileName;
            } 

            lastUriString = uriString; 
            lastFileName = SourceLineInfo.GetFileName(uriString); 
            return lastFileName;
        } 

        private void MarkSequencePoint(ISourceLineInfo sourceInfo) {
            Debug.Assert(this.isDebug);
 
            // Do not emit adjacent 0xfeefee sequence points, as that slows down stepping in the debugger
            if (sourceInfo.IsNoSource && this.lastSourceInfo != null && this.lastSourceInfo.IsNoSource) { 
                return; 
            }
 
            string sourceFile = GetFileName(sourceInfo);

        #if DEBUG
            if (XmlILTrace.IsEnabled) { 
                if (sourceInfo.IsNoSource)
                    this.writerDump.WriteLine("//[no source]"); 
                else { 
                    if (sourceFile != this.sourceFile) {
                        this.sourceFile = sourceFile; 
                        this.writerDump.WriteLine("// Source File '{0}'", this.sourceFile);
                    }
                    this.writerDump.WriteLine("//[{0},{1} -- {2},{3}]", sourceInfo.StartLine, sourceInfo.StartPos, sourceInfo.EndLine, sourceInfo.EndPos);
                } 
            }
        #endif 
            ISymbolDocumentWriter symDoc = this.module.AddSourceDocument(sourceFile); 
            this.ilgen.MarkSequencePoint(symDoc, sourceInfo.StartLine, sourceInfo.StartPos, sourceInfo.EndLine, sourceInfo.EndPos);
            this.lastSourceInfo = sourceInfo; 
        }


        //----------------------------------------------- 
        // Pass through to ILGenerator
        //----------------------------------------------- 
 
        public Label DefineLabel() {
            Label lbl = this.ilgen.DefineLabel(); 

        #if DEBUG
            if (XmlILTrace.IsEnabled)
                this.symbols.Add(lbl, ++this.lblNum); 
        #endif
 
            return lbl; 
        }
 
        public void MarkLabel(Label lbl) {
            if (this.lastSourceInfo != null && !this.lastSourceInfo.IsNoSource) {
                // Emit a "no source" sequence point, otherwise the debugger would show
                // a wrong line if we jumped to this label from another place 
                DebugSequencePoint(SourceLineInfo.NoSource);
            } 
 
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("Label {0}:", this.symbols[lbl]);
        #endif

            this.ilgen.MarkLabel(lbl); 
        }
 
        public void Emit(OpCode opcode) { 
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0}", opcode.Name);
        #endif
            this.ilgen.Emit(opcode);
        } 

        public void Emit(OpCode opcode, byte byteVal) { 
        #if DEBUG 
            if (XmlILTrace.IsEnabled)
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, byteVal); 
        #endif
            this.ilgen.Emit(opcode, byteVal);
        }
 
        public void Emit(OpCode opcode, ConstructorInfo constrInfo) {
        #if DEBUG 
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, constrInfo);
        #endif 
            this.ilgen.Emit(opcode, constrInfo);
        }

        public void Emit(OpCode opcode, double dblVal) { 
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, dblVal); 
        #endif
            this.ilgen.Emit(opcode, dblVal); 
        }

        public void Emit(OpCode opcode, float fltVal) {
        #if DEBUG 
            if (XmlILTrace.IsEnabled)
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, fltVal); 
        #endif 
            this.ilgen.Emit(opcode, fltVal);
        } 

        public void Emit(OpCode opcode, FieldInfo fldInfo) {
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, fldInfo.Name);
        #endif 
            this.ilgen.Emit(opcode, fldInfo); 
        }
 
        public void Emit(OpCode opcode, short shrtVal) {
            Debug.Assert(opcode.OperandType == OperandType.ShortInlineI);
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, shrtVal);
        #endif 
            this.ilgen.Emit(opcode, shrtVal); 
        }
 
        public void Emit(OpCode opcode, int intVal) {
            Debug.Assert(opcode.OperandType == OperandType.InlineI || opcode.OperandType == OperandType.InlineVar);
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, intVal);
        #endif 
            this.ilgen.Emit(opcode, intVal); 
        }
 
        public void Emit(OpCode opcode, long longVal) {
            Debug.Assert(opcode.OperandType == OperandType.InlineI8);
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, longVal);
        #endif 
            this.ilgen.Emit(opcode, longVal); 
        }
 
        public void Emit(OpCode opcode, Label lblVal) {
            Debug.Assert(!opcode.Equals(OpCodes.Br) && !opcode.Equals(OpCodes.Br_S), "Use EmitUnconditionalBranch and be careful not to emit unverifiable code.");
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} Label {1}", opcode.Name, this.symbols[lblVal]);
        #endif 
            this.ilgen.Emit(opcode, lblVal); 
        }
 
        public void Emit(OpCode opcode, Label[] arrLabels) {
        #if DEBUG
            if (XmlILTrace.IsEnabled) {
                this.writerDump.Write("  {0, -10} (Label {1}", opcode.Name, arrLabels.Length != 0 ? this.symbols[arrLabels[0]].ToString() : ""); 
                for (int i = 1; i < arrLabels.Length; i++) {
                    this.writerDump.Write(", Label {0}", this.symbols[arrLabels[i]]); 
                } 
                this.writerDump.WriteLine(")");
            } 
        #endif
            this.ilgen.Emit(opcode, arrLabels);
        }
 
        public void Emit(OpCode opcode, LocalBuilder locBldr) {
        #if DEBUG 
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1} ({2})", opcode.Name, this.symbols[locBldr], locBldr.LocalType.Name);
        #endif 
            this.ilgen.Emit(opcode, locBldr);
        }

        public void Emit(OpCode opcode, MethodInfo methInfo) { 
            Debug.Assert(!opcode.Equals(OpCodes.Call) && !opcode.Equals(OpCodes.Callvirt), "Use Call so that debug information will be output correctly.");
        #if DEBUG 
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, methInfo.Name);
        #endif 
            this.ilgen.Emit(opcode, methInfo);
        }

        public void Emit(OpCode opcode, sbyte sbyteVal) { 
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, sbyteVal); 
        #endif
            this.ilgen.Emit(opcode, sbyteVal); 
        }

        public void Emit(OpCode opcode, string strVal) {
        #if DEBUG 
            if (XmlILTrace.IsEnabled)
                this.writerDump.WriteLine("  {0, -10} \"{1}\"", opcode.Name, strVal); 
        #endif 
            this.ilgen.Emit(opcode, strVal);
        } 

        public void Emit(OpCode opcode, Type typVal) {
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, typVal);
        #endif 
            this.ilgen.Emit(opcode, typVal); 
        }
 
        /// 
        /// Unconditional branch opcodes (OpCode.Br, OpCode.Br_S) can lead to unverifiable code in the following cases:
        ///
        ///   # DEAD CODE CASE 
        ///     ldc_i4  1       # Stack depth == 1
        ///     br      Label2 
        ///   Label1: 
        ///     nop             # Dead code, so IL rules assume stack depth == 0.  This causes a verification error,
        ///                     # since next instruction has depth == 1 
        ///   Label2:
        ///     pop             # Stack depth == 1
        ///     ret
        /// 
        ///   # LATE BRANCH CASE
        ///     ldc_i4  1       # Stack depth == 1 
        ///     br      Label2 
        ///   Label1:
        ///     nop             # Not dead code, but since branch comes from below, IL rules assume stack depth = 0. 
        ///                     # This causes a verification error, since next instruction has depth == 1
        ///   Label2:
        ///     pop             # Stack depth == 1
        ///     ret 
        ///   Label3:
        ///     br      Label1  # Stack depth == 1 
        /// 
        /// This method works around the above limitations by using Brtrue or Brfalse in the following way:
        /// 
        ///     ldc_i4  1       # Since this test is always true, this is a way of creating a path to the code that
        ///     brtrue  Label   # follows the brtrue instruction.
        ///
        ///     ldc_i4  1       # Since this test is always false, this is a way of creating a path to the code that 
        ///     brfalse Label   # starts at Label.
        /// 
        /// 1. If opcode == Brtrue or Brtrue_S, then 1 will be pushed and brtrue instruction will be generated. 
        /// 2. If opcode == Brfalse or Brfalse_S, then 1 will be pushed and brfalse instruction will be generated.
        /// 3. If opcode == Br or Br_S, then a br instruction will be generated. 
        /// 
        public void EmitUnconditionalBranch(OpCode opcode, Label lblTarget) {
            if (!opcode.Equals(OpCodes.Br) && !opcode.Equals(OpCodes.Br_S)) {
                Debug.Assert(opcode.Equals(OpCodes.Brtrue) || opcode.Equals(OpCodes.Brtrue_S) || 
                             opcode.Equals(OpCodes.Brfalse) || opcode.Equals(OpCodes.Brfalse_S));
                Emit(OpCodes.Ldc_I4_1); 
            } 

        #if DEBUG 
            if (XmlILTrace.IsEnabled)
                this.writerDump.WriteLine("  {0, -10} Label {1}", opcode.Name, this.symbols[lblTarget]);
        #endif
            this.ilgen.Emit(opcode, lblTarget); 

            if (this.lastSourceInfo != null && (opcode.Equals(OpCodes.Br) || opcode.Equals(OpCodes.Br_S))) { 
                // Emit a "no source" sequence point, otherwise the following label will be preceded 
                // with a dead Nop operation, which may lead to unverifiable code (SQLBUDT 423393).
                // We are guaranteed not to emit adjacent sequence points because Br or Br_S 
                // instruction precedes this sequence point, and a Nop instruction precedes other
                // sequence points.
                MarkSequencePoint(SourceLineInfo.NoSource);
            } 
        }
    } 
} 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// [....] 
//-----------------------------------------------------------------------------
using System; 
using System.Globalization; 
using System.Xml;
using System.Xml.XPath; 
using System.Xml.Schema;
using System.Text;
using System.IO;
using System.Collections; 
using System.Collections.Generic;
using System.Reflection; 
using System.Reflection.Emit; 
using System.Security;
using System.Diagnostics; 
using System.Diagnostics.SymbolStore;
using System.Xml.Xsl.Qil;
using System.Xml.Xsl.Runtime;
 
namespace System.Xml.Xsl.IlGen {
    using Res = System.Xml.Utils.Res; 
 
    /// 
    /// List of all XmlIL runtime constructors. 
    /// 
    internal class XmlILStorageMethods {
        // Aggregates
        public MethodInfo AggAvg; 
        public MethodInfo AggAvgResult;
        public MethodInfo AggCreate; 
        public MethodInfo AggIsEmpty; 
        public MethodInfo AggMax;
        public MethodInfo AggMaxResult; 
        public MethodInfo AggMin;
        public MethodInfo AggMinResult;
        public MethodInfo AggSum;
        public MethodInfo AggSumResult; 

        // Sequences 
        public Type SeqType; 
        public FieldInfo SeqEmpty;
        public MethodInfo SeqReuse; 
        public MethodInfo SeqReuseSgl;
        public MethodInfo SeqAdd;
        public MethodInfo SeqSortByKeys;
 
        // IList<>
        public Type IListType; 
        public MethodInfo IListCount; 
        public MethodInfo IListItem;
 
        // XPathItem
        public MethodInfo ValueAs;

        // ToAtomicValue 
        public MethodInfo ToAtomicValue;
 
        public XmlILStorageMethods(Type storageType) { 
            // Aggregates
            if (storageType == typeof(int) || storageType == typeof(long) || 
                storageType == typeof(decimal) || storageType == typeof(double)) {

                Type aggType = Type.GetType("System.Xml.Xsl.Runtime." + storageType.Name + "Aggregator");
                AggAvg = XmlILMethods.GetMethod(aggType, "Average"); 
                AggAvgResult = XmlILMethods.GetMethod(aggType, "get_AverageResult");
                AggCreate = XmlILMethods.GetMethod(aggType, "Create"); 
                AggIsEmpty = XmlILMethods.GetMethod(aggType, "get_IsEmpty"); 
                AggMax = XmlILMethods.GetMethod(aggType, "Maximum");
                AggMaxResult = XmlILMethods.GetMethod(aggType, "get_MaximumResult"); 
                AggMin = XmlILMethods.GetMethod(aggType, "Minimum");
                AggMinResult = XmlILMethods.GetMethod(aggType, "get_MinimumResult");
                AggSum = XmlILMethods.GetMethod(aggType, "Sum");
                AggSumResult = XmlILMethods.GetMethod(aggType, "get_SumResult"); 
            }
 
            // Sequences 
            if (storageType == typeof(XPathNavigator)) {
                SeqType = typeof(XmlQueryNodeSequence); 
                SeqAdd = XmlILMethods.GetMethod(SeqType, "AddClone");
            }
            else if (storageType == typeof(XPathItem)) {
                SeqType = typeof(XmlQueryItemSequence); 
                SeqAdd = XmlILMethods.GetMethod(SeqType, "AddClone");
            } 
            else { 
                SeqType = typeof(XmlQuerySequence<>).MakeGenericType(storageType);
                SeqAdd = XmlILMethods.GetMethod(SeqType, "Add"); 
            }

            SeqEmpty = SeqType.GetField("Empty");
            SeqReuse = XmlILMethods.GetMethod(SeqType, "CreateOrReuse", SeqType); 
            SeqReuseSgl = XmlILMethods.GetMethod(SeqType, "CreateOrReuse", SeqType, storageType);
            SeqSortByKeys = XmlILMethods.GetMethod(SeqType, "SortByKeys"); 
 
            // IList<>
            IListType = typeof(IList<>).MakeGenericType(storageType); 
            IListItem = XmlILMethods.GetMethod(IListType, "get_Item");
            IListCount = XmlILMethods.GetMethod(typeof(ICollection<>).MakeGenericType(storageType), "get_Count");

            // XPathItem.ValueAsXXX 
            if (storageType == typeof(string))
                ValueAs = XmlILMethods.GetMethod(typeof(XPathItem), "get_Value"); 
            else if (storageType == typeof(int)) 
                ValueAs = XmlILMethods.GetMethod(typeof(XPathItem), "get_ValueAsInt");
            else if (storageType == typeof(long)) 
                ValueAs = XmlILMethods.GetMethod(typeof(XPathItem), "get_ValueAsLong");
            else if (storageType == typeof(DateTime))
                ValueAs = XmlILMethods.GetMethod(typeof(XPathItem), "get_ValueAsDateTime");
            else if (storageType == typeof(double)) 
                ValueAs = XmlILMethods.GetMethod(typeof(XPathItem), "get_ValueAsDouble");
            else if (storageType == typeof(bool)) 
                ValueAs = XmlILMethods.GetMethod(typeof(XPathItem), "get_ValueAsBoolean"); 

            // XmlILStorageConverter.XXXToAtomicValue 
            if (storageType == typeof(byte[]))
                ToAtomicValue = XmlILMethods.GetMethod(typeof(XmlILStorageConverter), "BytesToAtomicValue");
            else if (storageType != typeof(XPathItem) && storageType != typeof(XPathNavigator))
                ToAtomicValue = XmlILMethods.GetMethod(typeof(XmlILStorageConverter), storageType.Name + "ToAtomicValue"); 
        }
    } 
 
    /// 
    /// List of all XmlIL runtime constructors. 
    /// 
    internal static class XmlILConstructors {
        public static readonly ConstructorInfo DecFromParts = GetConstructor(typeof(decimal), typeof(int), typeof(int), typeof(int), typeof(bool), typeof(byte));
        public static readonly ConstructorInfo DecFromInt32 = GetConstructor(typeof(decimal), typeof(int)); 
        public static readonly ConstructorInfo DecFromInt64 = GetConstructor(typeof(decimal), typeof(long));
        public static readonly ConstructorInfo Debuggable = GetConstructor(typeof(DebuggableAttribute), typeof(DebuggableAttribute.DebuggingModes)); 
        public static readonly ConstructorInfo NonUserCode = GetConstructor(typeof(DebuggerNonUserCodeAttribute)); 
        public static readonly ConstructorInfo QName = GetConstructor(typeof(XmlQualifiedName), typeof(string), typeof(string));
        public static readonly ConstructorInfo StepThrough = GetConstructor(typeof(DebuggerStepThroughAttribute)); 
        public static readonly ConstructorInfo Transparent = GetConstructor(typeof(SecurityTransparentAttribute));

        private static ConstructorInfo GetConstructor(Type className) {
            ConstructorInfo constrInfo = className.GetConstructor(new Type[] {}); 
            Debug.Assert(constrInfo != null, "Constructor " + className + " cannot be null.");
            return constrInfo; 
        } 

        private static ConstructorInfo GetConstructor(Type className, params Type[] args) { 
            ConstructorInfo constrInfo = className.GetConstructor(args);
            Debug.Assert(constrInfo != null, "Constructor " + className + " cannot be null.");
            return constrInfo;
        } 
    }
 
 
    /// 
    /// List of all XmlIL runtime methods. 
    /// 
    internal static class XmlILMethods {
        // Iterators
        public static readonly MethodInfo AncCreate = GetMethod(typeof(AncestorIterator), "Create"); 
        public static readonly MethodInfo AncNext = GetMethod(typeof(AncestorIterator), "MoveNext");
        public static readonly MethodInfo AncDOCreate = GetMethod(typeof(AncestorDocOrderIterator), "Create"); 
        public static readonly MethodInfo AncDONext = GetMethod(typeof(AncestorDocOrderIterator), "MoveNext"); 
        public static readonly MethodInfo AttrContentCreate = GetMethod(typeof(AttributeContentIterator), "Create");
        public static readonly MethodInfo AttrContentNext = GetMethod(typeof(AttributeContentIterator), "MoveNext"); 
        public static readonly MethodInfo AttrCreate = GetMethod(typeof(AttributeIterator), "Create");
        public static readonly MethodInfo AttrNext = GetMethod(typeof(AttributeIterator), "MoveNext");
        public static readonly MethodInfo ContentCreate = GetMethod(typeof(ContentIterator), "Create");
        public static readonly MethodInfo ContentNext = GetMethod(typeof(ContentIterator), "MoveNext"); 
        public static readonly MethodInfo ContentMergeCreate = GetMethod(typeof(ContentMergeIterator), "Create");
        public static readonly MethodInfo ContentMergeNext = GetMethod(typeof(ContentMergeIterator), "MoveNext"); 
        public static readonly MethodInfo DescCreate = GetMethod(typeof(DescendantIterator), "Create"); 
        public static readonly MethodInfo DescNext = GetMethod(typeof(DescendantIterator), "MoveNext");
        public static readonly MethodInfo DescMergeCreate = GetMethod(typeof(DescendantMergeIterator), "Create"); 
        public static readonly MethodInfo DescMergeNext = GetMethod(typeof(DescendantMergeIterator), "MoveNext");
        public static readonly MethodInfo DiffCreate = GetMethod(typeof(DifferenceIterator), "Create");
        public static readonly MethodInfo DiffNext = GetMethod(typeof(DifferenceIterator), "MoveNext");
        public static readonly MethodInfo DodMergeCreate = GetMethod(typeof(DodSequenceMerge), "Create"); 
        public static readonly MethodInfo DodMergeAdd = GetMethod(typeof(DodSequenceMerge), "AddSequence");
        public static readonly MethodInfo DodMergeSeq = GetMethod(typeof(DodSequenceMerge), "MergeSequences"); 
        public static readonly MethodInfo ElemContentCreate = GetMethod(typeof(ElementContentIterator), "Create"); 
        public static readonly MethodInfo ElemContentNext = GetMethod(typeof(ElementContentIterator), "MoveNext");
        public static readonly MethodInfo FollSibCreate = GetMethod(typeof(FollowingSiblingIterator), "Create"); 
        public static readonly MethodInfo FollSibNext = GetMethod(typeof(FollowingSiblingIterator), "MoveNext");
        public static readonly MethodInfo FollSibMergeCreate = GetMethod(typeof(FollowingSiblingMergeIterator), "Create");
        public static readonly MethodInfo FollSibMergeNext = GetMethod(typeof(FollowingSiblingMergeIterator), "MoveNext");
        public static readonly MethodInfo IdCreate = GetMethod(typeof(IdIterator), "Create"); 
        public static readonly MethodInfo IdNext = GetMethod(typeof(IdIterator), "MoveNext");
        public static readonly MethodInfo InterCreate = GetMethod(typeof(IntersectIterator), "Create"); 
        public static readonly MethodInfo InterNext = GetMethod(typeof(IntersectIterator), "MoveNext"); 
        public static readonly MethodInfo KindContentCreate = GetMethod(typeof(NodeKindContentIterator), "Create");
        public static readonly MethodInfo KindContentNext = GetMethod(typeof(NodeKindContentIterator), "MoveNext"); 
        public static readonly MethodInfo NmspCreate = GetMethod(typeof(NamespaceIterator), "Create");
        public static readonly MethodInfo NmspNext = GetMethod(typeof(NamespaceIterator), "MoveNext");
        public static readonly MethodInfo NodeRangeCreate = GetMethod(typeof(NodeRangeIterator), "Create");
        public static readonly MethodInfo NodeRangeNext = GetMethod(typeof(NodeRangeIterator), "MoveNext"); 
        public static readonly MethodInfo ParentCreate = GetMethod(typeof(ParentIterator), "Create");
        public static readonly MethodInfo ParentNext = GetMethod(typeof(ParentIterator), "MoveNext"); 
        public static readonly MethodInfo PrecCreate = GetMethod(typeof(PrecedingIterator), "Create"); 
        public static readonly MethodInfo PrecNext = GetMethod(typeof(PrecedingIterator), "MoveNext");
        public static readonly MethodInfo PreSibCreate = GetMethod(typeof(PrecedingSiblingIterator), "Create"); 
        public static readonly MethodInfo PreSibNext = GetMethod(typeof(PrecedingSiblingIterator), "MoveNext");
        public static readonly MethodInfo PreSibDOCreate = GetMethod(typeof(PrecedingSiblingDocOrderIterator), "Create");
        public static readonly MethodInfo PreSibDONext = GetMethod(typeof(PrecedingSiblingDocOrderIterator), "MoveNext");
        public static readonly MethodInfo SortKeyCreate = GetMethod(typeof(XmlSortKeyAccumulator), "Create"); 
        public static readonly MethodInfo SortKeyDateTime = GetMethod(typeof(XmlSortKeyAccumulator), "AddDateTimeSortKey");
        public static readonly MethodInfo SortKeyDecimal = GetMethod(typeof(XmlSortKeyAccumulator), "AddDecimalSortKey"); 
        public static readonly MethodInfo SortKeyDouble = GetMethod(typeof(XmlSortKeyAccumulator), "AddDoubleSortKey"); 
        public static readonly MethodInfo SortKeyEmpty = GetMethod(typeof(XmlSortKeyAccumulator), "AddEmptySortKey");
        public static readonly MethodInfo SortKeyFinish = GetMethod(typeof(XmlSortKeyAccumulator), "FinishSortKeys"); 
        public static readonly MethodInfo SortKeyInt = GetMethod(typeof(XmlSortKeyAccumulator), "AddIntSortKey");
        public static readonly MethodInfo SortKeyInteger = GetMethod(typeof(XmlSortKeyAccumulator), "AddIntegerSortKey");
        public static readonly MethodInfo SortKeyKeys = GetMethod(typeof(XmlSortKeyAccumulator), "get_Keys");
        public static readonly MethodInfo SortKeyString = GetMethod(typeof(XmlSortKeyAccumulator), "AddStringSortKey"); 
        public static readonly MethodInfo UnionCreate = GetMethod(typeof(UnionIterator), "Create");
        public static readonly MethodInfo UnionNext = GetMethod(typeof(UnionIterator), "MoveNext"); 
        public static readonly MethodInfo XPFollCreate = GetMethod(typeof(XPathFollowingIterator), "Create"); 
        public static readonly MethodInfo XPFollNext = GetMethod(typeof(XPathFollowingIterator), "MoveNext");
        public static readonly MethodInfo XPFollMergeCreate = GetMethod(typeof(XPathFollowingMergeIterator), "Create"); 
        public static readonly MethodInfo XPFollMergeNext = GetMethod(typeof(XPathFollowingMergeIterator), "MoveNext");
        public static readonly MethodInfo XPPrecCreate = GetMethod(typeof(XPathPrecedingIterator), "Create");
        public static readonly MethodInfo XPPrecNext = GetMethod(typeof(XPathPrecedingIterator), "MoveNext");
        public static readonly MethodInfo XPPrecDOCreate = GetMethod(typeof(XPathPrecedingDocOrderIterator), "Create"); 
        public static readonly MethodInfo XPPrecDONext = GetMethod(typeof(XPathPrecedingDocOrderIterator), "MoveNext");
        public static readonly MethodInfo XPPrecMergeCreate = GetMethod(typeof(XPathPrecedingMergeIterator), "Create"); 
        public static readonly MethodInfo XPPrecMergeNext = GetMethod(typeof(XPathPrecedingMergeIterator), "MoveNext"); 

        // XmlQueryRuntime 
        public static readonly MethodInfo AddNewIndex = GetMethod(typeof(XmlQueryRuntime), "AddNewIndex");
        public static readonly MethodInfo ChangeTypeXsltArg = GetMethod(typeof(XmlQueryRuntime), "ChangeTypeXsltArgument", typeof(int), typeof(object), typeof(Type));
        public static readonly MethodInfo ChangeTypeXsltResult = GetMethod(typeof(XmlQueryRuntime), "ChangeTypeXsltResult");
        public static readonly MethodInfo CompPos = GetMethod(typeof(XmlQueryRuntime), "ComparePosition"); 
        public static readonly MethodInfo Context = GetMethod(typeof(XmlQueryRuntime), "get_ExternalContext");
        public static readonly MethodInfo CreateCollation = GetMethod(typeof(XmlQueryRuntime), "CreateCollation"); 
        public static readonly MethodInfo DocOrder = GetMethod(typeof(XmlQueryRuntime), "DocOrderDistinct"); 
        public static readonly MethodInfo EndRtfConstr = GetMethod(typeof(XmlQueryRuntime), "EndRtfConstruction");
        public static readonly MethodInfo EndSeqConstr = GetMethod(typeof(XmlQueryRuntime), "EndSequenceConstruction"); 
        public static readonly MethodInfo FindIndex = GetMethod(typeof(XmlQueryRuntime), "FindIndex");
        public static readonly MethodInfo GenId = GetMethod(typeof(XmlQueryRuntime), "GenerateId");
        public static readonly MethodInfo GetAtomizedName = GetMethod(typeof(XmlQueryRuntime), "GetAtomizedName");
        public static readonly MethodInfo GetCollation = GetMethod(typeof(XmlQueryRuntime), "GetCollation"); 
        public static readonly MethodInfo GetEarly = GetMethod(typeof(XmlQueryRuntime), "GetEarlyBoundObject");
        public static readonly MethodInfo GetNameFilter = GetMethod(typeof(XmlQueryRuntime), "GetNameFilter"); 
        public static readonly MethodInfo GetOutput = GetMethod(typeof(XmlQueryRuntime), "get_Output"); 
        public static readonly MethodInfo GetGlobalValue = GetMethod(typeof(XmlQueryRuntime), "GetGlobalValue");
        public static readonly MethodInfo GetTypeFilter = GetMethod(typeof(XmlQueryRuntime), "GetTypeFilter"); 
        public static readonly MethodInfo GlobalComputed = GetMethod(typeof(XmlQueryRuntime), "IsGlobalComputed");
        public static readonly MethodInfo ItemMatchesCode = GetMethod(typeof(XmlQueryRuntime), "MatchesXmlType", typeof(XPathItem), typeof(XmlTypeCode));
        public static readonly MethodInfo ItemMatchesType = GetMethod(typeof(XmlQueryRuntime), "MatchesXmlType", typeof(XPathItem), typeof(int));
        public static readonly MethodInfo QNameEqualLit = GetMethod(typeof(XmlQueryRuntime), "IsQNameEqual", typeof(XPathNavigator), typeof(int), typeof(int)); 
        public static readonly MethodInfo QNameEqualNav = GetMethod(typeof(XmlQueryRuntime), "IsQNameEqual", typeof(XPathNavigator), typeof(XPathNavigator));
        public static readonly MethodInfo RtfConstr = GetMethod(typeof(XmlQueryRuntime), "TextRtfConstruction"); 
        public static readonly MethodInfo SendMessage = GetMethod(typeof(XmlQueryRuntime), "SendMessage"); 
        public static readonly MethodInfo SeqMatchesCode = GetMethod(typeof(XmlQueryRuntime), "MatchesXmlType", typeof(IList), typeof(XmlTypeCode));
        public static readonly MethodInfo SeqMatchesType = GetMethod(typeof(XmlQueryRuntime), "MatchesXmlType", typeof(IList), typeof(int)); 
        public static readonly MethodInfo SetGlobalValue = GetMethod(typeof(XmlQueryRuntime), "SetGlobalValue");
        public static readonly MethodInfo StartRtfConstr = GetMethod(typeof(XmlQueryRuntime), "StartRtfConstruction");
        public static readonly MethodInfo StartSeqConstr = GetMethod(typeof(XmlQueryRuntime), "StartSequenceConstruction");
        public static readonly MethodInfo TagAndMappings = GetMethod(typeof(XmlQueryRuntime), "ParseTagName", typeof(string), typeof(int)); 
        public static readonly MethodInfo TagAndNamespace = GetMethod(typeof(XmlQueryRuntime), "ParseTagName", typeof(string), typeof(string));
        public static readonly MethodInfo ThrowException = GetMethod(typeof(XmlQueryRuntime), "ThrowException"); 
        public static readonly MethodInfo XsltLib = GetMethod(typeof(XmlQueryRuntime), "get_XsltFunctions"); 

        // XmlQueryContext 
        public static readonly MethodInfo GetDataSource = GetMethod(typeof(XmlQueryContext), "GetDataSource");
        public static readonly MethodInfo GetDefaultDataSource = GetMethod(typeof(XmlQueryContext), "get_DefaultDataSource");
        public static readonly MethodInfo GetParam = GetMethod(typeof(XmlQueryContext), "GetParameter");
        public static readonly MethodInfo InvokeXsltLate = GetMethod(typeof(XmlQueryContext), "InvokeXsltLateBoundFunction"); 

        // XmlILIndex 
        public static readonly MethodInfo IndexAdd = GetMethod(typeof(XmlILIndex), "Add"); 
        public static readonly MethodInfo IndexLookup = GetMethod(typeof(XmlILIndex), "Lookup");
 
        // XPathItem
        public static readonly MethodInfo ItemIsNode = GetMethod(typeof(XPathItem), "get_IsNode");
        public static readonly MethodInfo Value = GetMethod(typeof(XPathItem), "get_Value");
        public static readonly MethodInfo ValueAsAny = GetMethod(typeof(XPathItem), "ValueAs", typeof(Type), typeof(IXmlNamespaceResolver)); 

        // XPathNavigator 
        public static readonly MethodInfo NavClone = GetMethod(typeof(XPathNavigator), "Clone"); 
        public static readonly MethodInfo NavLocalName = GetMethod(typeof(XPathNavigator), "get_LocalName");
        public static readonly MethodInfo NavMoveAttr = GetMethod(typeof(XPathNavigator), "MoveToAttribute", typeof(string), typeof(string)); 
        public static readonly MethodInfo NavMoveId = GetMethod(typeof(XPathNavigator), "MoveToId");
        public static readonly MethodInfo NavMoveParent = GetMethod(typeof(XPathNavigator), "MoveToParent");
        public static readonly MethodInfo NavMoveRoot = GetMethod(typeof(XPathNavigator), "MoveToRoot");
        public static readonly MethodInfo NavMoveTo = GetMethod(typeof(XPathNavigator), "MoveTo"); 
        public static readonly MethodInfo NavNmsp = GetMethod(typeof(XPathNavigator), "get_NamespaceURI");
        public static readonly MethodInfo NavPrefix = GetMethod(typeof(XPathNavigator), "get_Prefix"); 
        public static readonly MethodInfo NavSamePos = GetMethod(typeof(XPathNavigator), "IsSamePosition"); 
        public static readonly MethodInfo NavType = GetMethod(typeof(XPathNavigator), "get_NodeType");
 
        // XmlQueryOutput methods
        public static readonly MethodInfo StartElemLitName = GetMethod(typeof(XmlQueryOutput), "WriteStartElement", typeof(string), typeof(string), typeof(string));
        public static readonly MethodInfo StartElemLocName = GetMethod(typeof(XmlQueryOutput), "WriteStartElementLocalName", typeof(string));
        public static readonly MethodInfo EndElemStackName = GetMethod(typeof(XmlQueryOutput), "WriteEndElement"); 
        public static readonly MethodInfo StartAttrLitName = GetMethod(typeof(XmlQueryOutput), "WriteStartAttribute", typeof(string), typeof(string), typeof(string));
        public static readonly MethodInfo StartAttrLocName = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeLocalName", typeof(string)); 
        public static readonly MethodInfo EndAttr = GetMethod(typeof(XmlQueryOutput), "WriteEndAttribute"); 
        public static readonly MethodInfo Text = GetMethod(typeof(XmlQueryOutput), "WriteString");
        public static readonly MethodInfo NoEntText = GetMethod(typeof(XmlQueryOutput), "WriteRaw", typeof(string)); 

        public static readonly MethodInfo StartTree = GetMethod(typeof(XmlQueryOutput), "StartTree");
        public static readonly MethodInfo EndTree = GetMethod(typeof(XmlQueryOutput), "EndTree");
 
        public static readonly MethodInfo StartElemLitNameUn = GetMethod(typeof(XmlQueryOutput), "WriteStartElementUnchecked", typeof(string), typeof(string), typeof(string));
        public static readonly MethodInfo StartElemLocNameUn = GetMethod(typeof(XmlQueryOutput), "WriteStartElementUnchecked", typeof(string)); 
        public static readonly MethodInfo StartContentUn = GetMethod(typeof(XmlQueryOutput), "StartElementContentUnchecked"); 
        public static readonly MethodInfo EndElemLitNameUn = GetMethod(typeof(XmlQueryOutput), "WriteEndElementUnchecked", typeof(string), typeof(string), typeof(string));
        public static readonly MethodInfo EndElemLocNameUn = GetMethod(typeof(XmlQueryOutput), "WriteEndElementUnchecked", typeof(string)); 
        public static readonly MethodInfo StartAttrLitNameUn = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeUnchecked", typeof(string), typeof(string), typeof(string));
        public static readonly MethodInfo StartAttrLocNameUn = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeUnchecked", typeof(string));
        public static readonly MethodInfo EndAttrUn = GetMethod(typeof(XmlQueryOutput), "WriteEndAttributeUnchecked");
        public static readonly MethodInfo NamespaceDeclUn = GetMethod(typeof(XmlQueryOutput), "WriteNamespaceDeclarationUnchecked"); 
        public static readonly MethodInfo TextUn = GetMethod(typeof(XmlQueryOutput), "WriteStringUnchecked");
        public static readonly MethodInfo NoEntTextUn = GetMethod(typeof(XmlQueryOutput), "WriteRawUnchecked"); 
 
        public static readonly MethodInfo StartRoot = GetMethod(typeof(XmlQueryOutput), "WriteStartRoot");
        public static readonly MethodInfo EndRoot = GetMethod(typeof(XmlQueryOutput), "WriteEndRoot"); 
        public static readonly MethodInfo StartElemCopyName = GetMethod(typeof(XmlQueryOutput), "WriteStartElementComputed", typeof(XPathNavigator));
        public static readonly MethodInfo StartElemMapName = GetMethod(typeof(XmlQueryOutput), "WriteStartElementComputed", typeof(string), typeof(int));
        public static readonly MethodInfo StartElemNmspName = GetMethod(typeof(XmlQueryOutput), "WriteStartElementComputed", typeof(string), typeof(string));
        public static readonly MethodInfo StartElemQName = GetMethod(typeof(XmlQueryOutput), "WriteStartElementComputed", typeof(XmlQualifiedName)); 
        public static readonly MethodInfo StartAttrCopyName = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeComputed", typeof(XPathNavigator));
        public static readonly MethodInfo StartAttrMapName = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeComputed", typeof(string), typeof(int)); 
        public static readonly MethodInfo StartAttrNmspName = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeComputed", typeof(string), typeof(string)); 
        public static readonly MethodInfo StartAttrQName = GetMethod(typeof(XmlQueryOutput), "WriteStartAttributeComputed", typeof(XmlQualifiedName));
        public static readonly MethodInfo NamespaceDecl = GetMethod(typeof(XmlQueryOutput), "WriteNamespaceDeclaration"); 
        public static readonly MethodInfo StartComment = GetMethod(typeof(XmlQueryOutput), "WriteStartComment");
        public static readonly MethodInfo CommentText = GetMethod(typeof(XmlQueryOutput), "WriteCommentString");
        public static readonly MethodInfo EndComment = GetMethod(typeof(XmlQueryOutput), "WriteEndComment");
        public static readonly MethodInfo StartPI = GetMethod(typeof(XmlQueryOutput), "WriteStartProcessingInstruction"); 
        public static readonly MethodInfo PIText = GetMethod(typeof(XmlQueryOutput), "WriteProcessingInstructionString");
        public static readonly MethodInfo EndPI = GetMethod(typeof(XmlQueryOutput), "WriteEndProcessingInstruction"); 
        public static readonly MethodInfo WriteItem = GetMethod(typeof(XmlQueryOutput), "WriteItem"); 
        public static readonly MethodInfo CopyOf = GetMethod(typeof(XmlQueryOutput), "XsltCopyOf");
        public static readonly MethodInfo StartCopy = GetMethod(typeof(XmlQueryOutput), "StartCopy"); 
        public static readonly MethodInfo EndCopy = GetMethod(typeof(XmlQueryOutput), "EndCopy");

        // Datatypes
        public static readonly MethodInfo DecAdd = GetMethod(typeof(decimal), "Add"); 
        public static readonly MethodInfo DecCmp = GetMethod(typeof(decimal), "Compare", typeof(decimal), typeof(decimal));
        public static readonly MethodInfo DecEq = GetMethod(typeof(decimal), "Equals", typeof(decimal), typeof(decimal)); 
        public static readonly MethodInfo DecSub = GetMethod(typeof(decimal), "Subtract"); 
        public static readonly MethodInfo DecMul = GetMethod(typeof(decimal), "Multiply");
        public static readonly MethodInfo DecDiv = GetMethod(typeof(decimal), "Divide"); 
        public static readonly MethodInfo DecRem = GetMethod(typeof(decimal), "Remainder");
        public static readonly MethodInfo DecNeg = GetMethod(typeof(decimal), "Negate");
        public static readonly MethodInfo QNameEq = GetMethod(typeof(XmlQualifiedName), "Equals");
        public static readonly MethodInfo StrEq = GetMethod(typeof(string), "Equals", typeof(string), typeof(string)); 
        public static readonly MethodInfo StrCat2 = GetMethod(typeof(string), "Concat", typeof(string), typeof(string));
        public static readonly MethodInfo StrCat3 = GetMethod(typeof(string), "Concat", typeof(string), typeof(string), typeof(string)); 
        public static readonly MethodInfo StrCat4 = GetMethod(typeof(string), "Concat", typeof(string), typeof(string), typeof(string), typeof(string)); 
        public static readonly MethodInfo StrCmp = GetMethod(typeof(string), "CompareOrdinal", typeof(string), typeof(string));
        public static readonly MethodInfo StrLen = GetMethod(typeof(string), "get_Length"); 

        // XsltConvert
        public static readonly MethodInfo DblToDec = GetMethod(typeof(XsltConvert), "ToDecimal", typeof(double));
        public static readonly MethodInfo DblToInt = GetMethod(typeof(XsltConvert), "ToInt", typeof(double)); 
        public static readonly MethodInfo DblToLng = GetMethod(typeof(XsltConvert), "ToLong", typeof(double));
        public static readonly MethodInfo DblToStr = GetMethod(typeof(XsltConvert), "ToString", typeof(double)); 
        public static readonly MethodInfo DecToDbl = GetMethod(typeof(XsltConvert), "ToDouble", typeof(decimal)); 
        public static readonly MethodInfo DTToStr = GetMethod(typeof(XsltConvert), "ToString", typeof(DateTime));
        public static readonly MethodInfo IntToDbl = GetMethod(typeof(XsltConvert), "ToDouble", typeof(int)); 
        public static readonly MethodInfo LngToDbl = GetMethod(typeof(XsltConvert), "ToDouble", typeof(long));
        public static readonly MethodInfo StrToDbl = GetMethod(typeof(XsltConvert), "ToDouble", typeof(string));
        public static readonly MethodInfo StrToDT = GetMethod(typeof(XsltConvert), "ToDateTime", typeof(string));
 
        public static readonly MethodInfo ItemToBool = GetMethod(typeof(XsltConvert), "ToBoolean", typeof(XPathItem));
        public static readonly MethodInfo ItemToDbl = GetMethod(typeof(XsltConvert), "ToDouble", typeof(XPathItem)); 
        public static readonly MethodInfo ItemToStr = GetMethod(typeof(XsltConvert), "ToString", typeof(XPathItem)); 
        public static readonly MethodInfo ItemToNode = GetMethod(typeof(XsltConvert), "ToNode", typeof(XPathItem));
        public static readonly MethodInfo ItemToNodes = GetMethod(typeof(XsltConvert), "ToNodeSet", typeof(XPathItem)); 

        public static readonly MethodInfo ItemsToBool = GetMethod(typeof(XsltConvert), "ToBoolean", typeof(IList));
        public static readonly MethodInfo ItemsToDbl = GetMethod(typeof(XsltConvert), "ToDouble", typeof(IList));
        public static readonly MethodInfo ItemsToNode = GetMethod(typeof(XsltConvert), "ToNode", typeof(IList)); 
        public static readonly MethodInfo ItemsToNodes = GetMethod(typeof(XsltConvert), "ToNodeSet", typeof(IList));
        public static readonly MethodInfo ItemsToStr = GetMethod(typeof(XsltConvert), "ToString", typeof(IList)); 
 
        // StringConcat
        public static readonly MethodInfo StrCatCat = GetMethod(typeof(StringConcat), "Concat"); 
        public static readonly MethodInfo StrCatClear = GetMethod(typeof(StringConcat), "Clear");
        public static readonly MethodInfo StrCatResult = GetMethod(typeof(StringConcat), "GetResult");
        public static readonly MethodInfo StrCatDelim = GetMethod(typeof(StringConcat), "set_Delimiter");
 
        // XmlILStorageConverter
        public static readonly MethodInfo NavsToItems = GetMethod(typeof(XmlILStorageConverter), "NavigatorsToItems"); 
        public static readonly MethodInfo ItemsToNavs = GetMethod(typeof(XmlILStorageConverter), "ItemsToNavigators"); 

        // XmlQueryNodeSequence 
        public static readonly MethodInfo SetDod = GetMethod(typeof(XmlQueryNodeSequence), "set_IsDocOrderDistinct");

        // Miscellaneous
        public static readonly MethodInfo GetTypeFromHandle = GetMethod(typeof(Type), "GetTypeFromHandle"); 
        public static readonly MethodInfo InitializeArray = GetMethod(typeof(System.Runtime.CompilerServices.RuntimeHelpers), "InitializeArray");
        public static readonly Dictionary StorageMethods; 
 
        static XmlILMethods() {
            StorageMethods = new Dictionary(); 
            StorageMethods[typeof(string)] = new XmlILStorageMethods(typeof(string));
            StorageMethods[typeof(bool)] = new XmlILStorageMethods(typeof(bool));
            StorageMethods[typeof(int)] = new XmlILStorageMethods(typeof(int));
            StorageMethods[typeof(long)] = new XmlILStorageMethods(typeof(long)); 
            StorageMethods[typeof(decimal)] = new XmlILStorageMethods(typeof(decimal));
            StorageMethods[typeof(double)] = new XmlILStorageMethods(typeof(double)); 
            StorageMethods[typeof(float)] = new XmlILStorageMethods(typeof(float)); 
            StorageMethods[typeof(DateTime)] = new XmlILStorageMethods(typeof(DateTime));
            StorageMethods[typeof(byte[])] = new XmlILStorageMethods(typeof(byte[])); 
            StorageMethods[typeof(XmlQualifiedName)] = new XmlILStorageMethods(typeof(XmlQualifiedName));
            StorageMethods[typeof(TimeSpan)] = new XmlILStorageMethods(typeof(TimeSpan));
            StorageMethods[typeof(XPathItem)] = new XmlILStorageMethods(typeof(XPathItem));
            StorageMethods[typeof(XPathNavigator)] = new XmlILStorageMethods(typeof(XPathNavigator)); 
        }
 
        public static MethodInfo GetMethod(Type className, string methName) { 
            MethodInfo methInfo = className.GetMethod(methName);
            Debug.Assert(methInfo != null, "Method " + className.Name + "." + methName + " cannot be null."); 
            return methInfo;
        }

        public static MethodInfo GetMethod(Type className, string methName, params Type[] args) { 
            MethodInfo methInfo = className.GetMethod(methName, args);
            Debug.Assert(methInfo != null, "Method " + methName + " cannot be null."); 
            return methInfo; 
        }
    } 


    /// 
    /// When named nodes are constructed, there are several possible ways for their names to be created. 
    /// 
    internal enum GenerateNameType { 
        LiteralLocalName,       // Local name is a literal string; namespace is null 
        LiteralName,            // All parts of the name are literal strings
        CopiedName,             // Name should be copied from a navigator 
        TagNameAndMappings,     // Tagname contains prefix:localName and prefix is mapped to a namespace
        TagNameAndNamespace,    // Tagname contains prefix:localName and namespace is provided
        QName,                  // Name is computed QName (no prefix available)
        StackName,              // Element name has already been pushed onto XmlQueryOutput stack 
    }
 
    ///  
    /// Contains helper methods used during the code generation phase.
    ///  
    internal class GenerateHelper {
        private MethodBase methInfo;
        private ILGenerator ilgen;
        private LocalBuilder locXOut; 
        private XmlILModule module;
        private bool isDebug, initWriters; 
        private StaticDataManager staticData; 
        private ISourceLineInfo lastSourceInfo;
        private MethodInfo methSyncToNav; 

    #if DEBUG
        private int lblNum;
        private Hashtable symbols; 
        private int numLocals;
        private string sourceFile; 
        private TextWriter writerDump; 
    #endif
 
        /// 
        /// Cache metadata used during code-generation phase.
        /// 
        public GenerateHelper(XmlILModule module, bool isDebug) { 
            this.isDebug = isDebug;
            this.module = module; 
            this.staticData = new StaticDataManager(); 

        #if DEBUG 
            if (XmlILTrace.IsEnabled)
                XmlILTrace.PrepareTraceWriter("dump.il");
        #endif
        } 

        ///  
        /// Begin generating code within a new method. 
        /// 
        public void MethodBegin(MethodBase methInfo, ISourceLineInfo sourceInfo, bool initWriters) { 
            this.methInfo = methInfo;
            this.ilgen = XmlILModule.DefineMethodBody(methInfo);
            this.lastSourceInfo = null;
 
        #if DEBUG
            if (XmlILTrace.IsEnabled) { 
                this.numLocals = 0; 
                this.symbols = new Hashtable();
                this.lblNum = 0; 
                this.sourceFile = null;

                this.writerDump = XmlILTrace.GetTraceWriter("dump.il");
                this.writerDump.WriteLine(".method {0}()", methInfo.Name); 
                this.writerDump.WriteLine("{");
            } 
        #endif 

            if (this.isDebug) { 
                DebugStartScope();

                // DebugInfo: Sequence point just before generating code for this function
                if (sourceInfo != null) { 
                    // Don't call DebugSequencePoint, as it puts Nop *before* the sequence point.  That is
                    // wrong in this case, because we need source line information to be emitted before any 
                    // IL instruction so that stepping into this function won't end up in the assembly window. 
                    // We still guarantee that:
                    //   1. Two sequence points are never adjacent, since this is the 1st sequence point 
                    //   2. Stack depth is 0, since this is the very beginning of the method
                    MarkSequencePoint(sourceInfo);
                    Emit(OpCodes.Nop);
                } 
            }
 
            this.initWriters = false; 
            if (initWriters) {
                EnsureWriter(); 
                LoadQueryRuntime();
                Call(XmlILMethods.GetOutput);
                Emit(OpCodes.Stloc, this.locXOut);
            } 
        }
 
        ///  
        /// Generate "ret" instruction and branch fixup jump table.
        ///  
        public void MethodEnd() {
            Emit(OpCodes.Ret);

        #if DEBUG 
            if (XmlILTrace.IsEnabled) {
                this.writerDump.WriteLine("}"); 
                this.writerDump.WriteLine(""); 
                this.writerDump.Close();
            } 
        #endif

            if (this.isDebug)
                DebugEndScope(); 
        }
 
 
        //-----------------------------------------------
        // Helper Global Methods 
        //-----------------------------------------------

        /// 
        /// Call a static method which attempts to reuse a navigator. 
        /// 
        public void CallSyncToNavigator() { 
            // Get helper method from module 
            if (this.methSyncToNav == null)
                this.methSyncToNav = this.module.FindMethod("SyncToNavigator"); 

            Call(this.methSyncToNav);
        }
 
        //-----------------------------------------------
        // StaticDataManager 
        //----------------------------------------------- 

        ///  
        /// This internal class manages literal names, literal types, and storage for global variables.
        /// 
        public StaticDataManager StaticData {
            get { return this.staticData; } 
        }
 
 
        //-----------------------------------------------
        // Constants 
        //-----------------------------------------------

        /// 
        /// Generate the optimal Ldc_I4 instruction based on intVal. 
        /// 
        public void LoadInteger(int intVal) { 
            OpCode opcode; 

            if (intVal >= -1 && intVal < 9) { 
                switch (intVal) {
                    case -1: opcode = OpCodes.Ldc_I4_M1; break;
                    case 0: opcode = OpCodes.Ldc_I4_0; break;
                    case 1: opcode = OpCodes.Ldc_I4_1; break; 
                    case 2: opcode = OpCodes.Ldc_I4_2; break;
                    case 3: opcode = OpCodes.Ldc_I4_3; break; 
                    case 4: opcode = OpCodes.Ldc_I4_4; break; 
                    case 5: opcode = OpCodes.Ldc_I4_5; break;
                    case 6: opcode = OpCodes.Ldc_I4_6; break; 
                    case 7: opcode = OpCodes.Ldc_I4_7; break;
                    case 8: opcode = OpCodes.Ldc_I4_8; break;
                    default: Debug.Assert(false); return;
                } 
                Emit(opcode);
            } 
            else if (intVal >= -128 && intVal <= 127) 
                Emit(OpCodes.Ldc_I4_S, (sbyte) intVal);
            else 
                Emit(OpCodes.Ldc_I4, intVal);
        }

        public void LoadBoolean(bool boolVal) { 
            Emit(boolVal ? OpCodes.Ldc_I4_1 : OpCodes.Ldc_I4_0);
        } 
 
        public void LoadType(Type clrTyp) {
            Emit(OpCodes.Ldtoken, clrTyp); 
            Call(XmlILMethods.GetTypeFromHandle);
        }

 
        //-----------------------------------------------
        // Local variables 
        //----------------------------------------------- 

        ///  
        /// Generate a new local variable.  Add a numeric suffix to name that ensures that all
        /// local variable names will be unique (for readability).
        /// 
        public LocalBuilder DeclareLocal(string name, Type type) { 
            LocalBuilder locBldr = this.ilgen.DeclareLocal(type);
        #if DEBUG 
            if (XmlILTrace.IsEnabled) { 
                // Set name for internal MS debugging.  This is not the user-defined name--that will be set later
                if (this.isDebug) 
                    locBldr.SetLocalSymInfo(name + this.numLocals.ToString(CultureInfo.InvariantCulture));

                this.symbols.Add(locBldr, name + this.numLocals.ToString(CultureInfo.InvariantCulture));
                this.numLocals++; 
            }
        #endif 
            return locBldr; 
        }
 
        public void LoadQueryRuntime() {
            Emit(OpCodes.Ldarg_0);
        }
 
        public void LoadQueryContext() {
            Emit(OpCodes.Ldarg_0); 
            Call(XmlILMethods.Context); 
        }
 
        public void LoadXsltLibrary() {
            Emit(OpCodes.Ldarg_0);
            Call(XmlILMethods.XsltLib);
        } 

        public void LoadQueryOutput() { 
            Emit(OpCodes.Ldloc, this.locXOut); 
        }
 

        //-----------------------------------------------
        // Parameters
        //----------------------------------------------- 

        public void LoadParameter(int paramPos) { 
            switch (paramPos) { 
                case 0: Emit(OpCodes.Ldarg_0); break;
                case 1: Emit(OpCodes.Ldarg_1); break; 
                case 2: Emit(OpCodes.Ldarg_2); break;
                case 3: Emit(OpCodes.Ldarg_3); break;
                default:
                    if (paramPos <= 255) { 
                        Emit(OpCodes.Ldarg_S, (byte) paramPos);
                    } 
                    else if (paramPos <= ushort.MaxValue) { 
                        Emit(OpCodes.Ldarg, paramPos);
                    } 
                    else {
                        throw new XslTransformException(Res.XmlIl_TooManyParameters);
                    }
                    break; 
            }
        } 
 
        public void SetParameter(object paramId) {
            int paramPos = (int) paramId; 

            if (paramPos <= 255) {
                Emit(OpCodes.Starg_S, (byte) paramPos);
            } 
            else if (paramPos <= ushort.MaxValue) {
                Emit(OpCodes.Starg, (int) paramPos); 
            } 
            else {
                throw new XslTransformException(Res.XmlIl_TooManyParameters); 
            }
        }

        //----------------------------------------------- 
        // Labels
        //----------------------------------------------- 
 
        /// 
        /// Branch to lblBranch and anchor lblMark.  If lblBranch = lblMark, then no need 
        /// to generate a "br" to the next instruction.
        /// 
        public void BranchAndMark(Label lblBranch, Label lblMark) {
            if (!lblBranch.Equals(lblMark)) { 
                EmitUnconditionalBranch(OpCodes.Br, lblBranch);
            } 
            MarkLabel(lblMark); 
        }
 

        //-----------------------------------------------
        // Comparison
        //----------------------------------------------- 

        ///  
        /// Compare the top value on the stack with the specified i4 using the specified relational 
        /// comparison opcode, and branch to lblBranch if the result is true.
        ///  
        public void TestAndBranch(int i4, Label lblBranch, OpCode opcodeBranch) {
            switch (i4) {
                case 0:
                    // Beq or Bne can be shortened to Brfalse or Brtrue if comparing to 0 
                    if (opcodeBranch.Value == OpCodes.Beq.Value)
                        opcodeBranch = OpCodes.Brfalse; 
                    else if (opcodeBranch.Value == OpCodes.Beq_S.Value) 
                        opcodeBranch = OpCodes.Brfalse_S;
                    else if (opcodeBranch.Value == OpCodes.Bne_Un.Value) 
                        opcodeBranch = OpCodes.Brtrue;
                    else if (opcodeBranch.Value == OpCodes.Bne_Un_S.Value)
                        opcodeBranch = OpCodes.Brtrue_S;
                    else 
                        goto default;
                    break; 
 
                default:
                    // Cannot use shortcut, so push integer onto the stack 
                    LoadInteger(i4);
                    break;
            }
 
            Emit(opcodeBranch, lblBranch);
        } 
 
        /// 
        /// Assume a branch instruction has already been issued.  If isTrueBranch is true, then the 
        /// true path is linked to lblBranch.  Otherwise, the false path is linked to lblBranch.
        /// Convert this "branching" boolean logic into an explicit push of 1 or 0 onto the stack.
        /// 
        public void ConvBranchToBool(Label lblBranch, bool isTrueBranch) { 
            Label lblDone = DefineLabel();
 
            Emit(isTrueBranch ? OpCodes.Ldc_I4_0 : OpCodes.Ldc_I4_1); 
            EmitUnconditionalBranch(OpCodes.Br_S, lblDone);
            MarkLabel(lblBranch); 
            Emit(isTrueBranch ? OpCodes.Ldc_I4_1 : OpCodes.Ldc_I4_0);
            MarkLabel(lblDone);
        }
 

        //----------------------------------------------- 
        // Frequently used method and function calls 
        //-----------------------------------------------
 
        public void TailCall(MethodInfo meth) {
            Emit(OpCodes.Tailcall);
            Call(meth);
            Emit(OpCodes.Ret); 
        }
 
        [Conditional("DEBUG")] 
        private void TraceCall(OpCode opcode, MethodInfo meth) {
        #if DEBUG 
            if (XmlILTrace.IsEnabled) {
                StringBuilder strBldr = new StringBuilder();
                bool isFirst = true;
                string retType = ""; 

                if (!(meth is MethodBuilder)) { 
                    foreach (ParameterInfo paramInfo in meth.GetParameters()) { 
                        if (isFirst)
                            isFirst = false; 
                        else
                            strBldr.Append(", ");
                        strBldr.Append(paramInfo.ParameterType.Name);
                    } 
                    retType = meth.ReturnType.Name;
                } 
 
                this.writerDump.WriteLine("  {0, -10} {1} {2}({3})", new object[] {opcode.Name, retType, meth.Name, strBldr.ToString()});
            } 
        #endif
        }

        public void Call(MethodInfo meth) { 
            OpCode opcode = meth.IsVirtual || meth.IsAbstract ? OpCodes.Callvirt : OpCodes.Call;
 
            TraceCall(opcode, meth); 
            this.ilgen.Emit(opcode, meth);
 
            if (this.lastSourceInfo != null) {
                // Emit a "no source" sequence point, otherwise the debugger would return to the wrong line
                // once the call has finished.  We are guaranteed not to emit adjacent sequence points because
                // the Call instruction precedes this sequence point, and a nop instruction precedes other 
                // sequence points.
                MarkSequencePoint(SourceLineInfo.NoSource); 
            } 
        }
 
        //
        public void CallToken(MethodInfo meth) {
            Debug.Assert(!(methInfo is ConstructorBuilder));
            MethodBuilder methBldr = this.methInfo as MethodBuilder; 

            if (methBldr != null) { 
                // Using regular reflection emit, so get a token for the specified method. 
                // The token is only valid within scope of this method's body.
                OpCode opcode = meth.IsVirtual || meth.IsAbstract ? OpCodes.Callvirt : OpCodes.Call; 

                TraceCall(opcode, meth);
                this.ilgen.Emit(opcode, ((ModuleBuilder) methBldr.GetModule()).GetMethodToken(meth).Token);
 
                if (this.lastSourceInfo != null) {
                    // Emit a "no source" sequence point, otherwise the debugger would return to the wrong line 
                    // once the call has finished.  We are guaranteed not to emit adjacent sequence points because 
                    // the Call instruction precedes this sequence point, and a nop instruction precedes other
                    // sequence points. 
                    MarkSequencePoint(SourceLineInfo.NoSource);
                }
            }
            else { 
                // Using LCG, so no need to workaround
                Call(meth); 
            } 
        }
 
        public void Construct(ConstructorInfo constr) {
            Emit(OpCodes.Newobj, constr);
        }
 
        public void CallConcatStrings(int cStrings) {
            switch (cStrings) { 
                case 0: 
                    Emit(OpCodes.Ldstr, "");
                    break; 
                case 1:
                    break;
                case 2:
                    Call(XmlILMethods.StrCat2); 
                    break;
                case 3: 
                    Call(XmlILMethods.StrCat3); 
                    break;
                case 4: 
                    Call(XmlILMethods.StrCat4);
                    break;
                default:
                    Debug.Assert(false, "Shouldn't be called"); 
                    break;
            } 
        } 

        ///  
        /// Assume that an object reference is on the IL stack.  Change the static Clr type from "clrTypeSrc" to "clrTypeDst"
        /// 
        public void TreatAs(Type clrTypeSrc, Type clrTypeDst) {
            // If source = destination, then no-op 
            if (clrTypeSrc == clrTypeDst)
                return; 
 
            if (clrTypeSrc.IsValueType) {
                // If source is a value type, then destination may only be typeof(object), so box 
                Debug.Assert(clrTypeDst == typeof(object), "Invalid cast, since value types do not allow inheritance.");
                Emit(OpCodes.Box, clrTypeSrc);
            }
            else if (clrTypeDst.IsValueType) { 
                // If destination type is value type, then source may only be typeof(object), so unbox
                Debug.Assert(clrTypeSrc == typeof(object), "Invalid cast, since value types do not allow inheritance."); 
                Emit(OpCodes.Unbox, clrTypeDst); 
                Emit(OpCodes.Ldobj, clrTypeDst);
            } 
            else if (clrTypeDst != typeof(object)) {
                // If source is not a value type, and destination type is typeof(object), then no-op
                // Otherwise, use Castclass to change the static type
                Debug.Assert(clrTypeSrc.IsAssignableFrom(clrTypeDst) || clrTypeDst.IsAssignableFrom(clrTypeSrc), 
                             "Invalid cast, since source type and destination type are not in same inheritance hierarchy.");
                Emit(OpCodes.Castclass, clrTypeDst); 
            } 
        }
 

        //-----------------------------------------------
        // Datatype methods
        //----------------------------------------------- 

        public void ConstructLiteralDecimal(decimal dec) { 
            if (dec >= (decimal) int.MinValue && dec <= (decimal) int.MaxValue && decimal.Truncate(dec) == dec) { 
                // Decimal can be constructed from a 32-bit integer
                LoadInteger((int) dec); 
                Construct(XmlILConstructors.DecFromInt32);
            }
            else {
                int[] bits = Decimal.GetBits(dec); 

                LoadInteger(bits[0]); 
                LoadInteger(bits[1]); 
                LoadInteger(bits[2]);
                LoadBoolean(bits[3] < 0); 
                LoadInteger(bits[3] >> 16);
                Construct(XmlILConstructors.DecFromParts);
            }
        } 

        public void ConstructLiteralQName(string localName, string namespaceName) { 
            Emit(OpCodes.Ldstr, localName); 
            Emit(OpCodes.Ldstr, namespaceName);
            Construct(XmlILConstructors.QName); 
        }

        public void CallArithmeticOp(QilNodeType opType, XmlTypeCode code) {
            MethodInfo meth = null; 

            switch (code) { 
                case XmlTypeCode.Int: 
                case XmlTypeCode.Integer:
                case XmlTypeCode.Double: 
                case XmlTypeCode.Float:
                    switch (opType) {
                        case QilNodeType.Add: Emit(OpCodes.Add); break;
                        case QilNodeType.Subtract: Emit(OpCodes.Sub); break; 
                        case QilNodeType.Multiply: Emit(OpCodes.Mul); break;
                        case QilNodeType.Divide: Emit(OpCodes.Div); break; 
                        case QilNodeType.Modulo: Emit(OpCodes.Rem); break; 
                        case QilNodeType.Negate: Emit(OpCodes.Neg); break;
                        default: Debug.Assert(false, opType + " must be an arithmetic operation."); break; 
                    }
                    break;

                case XmlTypeCode.Decimal: 
                    switch (opType) {
                        case QilNodeType.Add: meth = XmlILMethods.DecAdd; break; 
                        case QilNodeType.Subtract: meth = XmlILMethods.DecSub; break; 
                        case QilNodeType.Multiply: meth = XmlILMethods.DecMul; break;
                        case QilNodeType.Divide: meth = XmlILMethods.DecDiv; break; 
                        case QilNodeType.Modulo: meth = XmlILMethods.DecRem; break;
                        case QilNodeType.Negate: meth = XmlILMethods.DecNeg; break;
                        default: Debug.Assert(false, opType + " must be an arithmetic operation."); break;
                    } 

                    Call(meth); 
                    break; 

                default: 
                    Debug.Assert(false, "The " + opType + " arithmetic operation cannot be performed on values of type " + code + ".");
                    break;
            }
        } 

        public void CallCompareEquals(XmlTypeCode code) { 
            MethodInfo meth = null; 

            switch (code) { 
                case XmlTypeCode.String: meth = XmlILMethods.StrEq; break;
                case XmlTypeCode.QName: meth = XmlILMethods.QNameEq; break;
                case XmlTypeCode.Decimal: meth = XmlILMethods.DecEq; break;
                default: 
                    Debug.Assert(false, "Type " + code + " does not support the equals operation.");
                    break; 
            } 

            Call(meth); 
        }

        public void CallCompare(XmlTypeCode code) {
            MethodInfo meth = null; 

            switch (code) { 
                case XmlTypeCode.String: meth = XmlILMethods.StrCmp; break; 
                case XmlTypeCode.Decimal: meth = XmlILMethods.DecCmp; break;
                default: 
                    Debug.Assert(false, "Type " + code + " does not support the equals operation.");
                    break;
            }
 
            Call(meth);
        } 
 

        //----------------------------------------------- 
        // XmlQueryRuntime function calls
        //-----------------------------------------------

        public void CallStartRtfConstruction(string baseUri) { 
            EnsureWriter();
            LoadQueryRuntime(); 
            Emit(OpCodes.Ldstr, baseUri); 
            Emit(OpCodes.Ldloca, this.locXOut);
            Call(XmlILMethods.StartRtfConstr); 
        }

        public void CallEndRtfConstruction() {
            LoadQueryRuntime(); 
            Emit(OpCodes.Ldloca, this.locXOut);
            Call(XmlILMethods.EndRtfConstr); 
        } 

        public void CallStartSequenceConstruction() { 
            EnsureWriter();
            LoadQueryRuntime();
            Emit(OpCodes.Ldloca, this.locXOut);
            Call(XmlILMethods.StartSeqConstr); 
        }
 
        public void CallEndSequenceConstruction() { 
            LoadQueryRuntime();
            Emit(OpCodes.Ldloca, this.locXOut); 
            Call(XmlILMethods.EndSeqConstr);
        }

        public void CallGetEarlyBoundObject(int idxObj, Type clrType) { 
            LoadQueryRuntime();
            LoadInteger(idxObj); 
            Call(XmlILMethods.GetEarly); 
            TreatAs(typeof(object), clrType);
        } 

        public void CallGetAtomizedName(int idxName) {
            LoadQueryRuntime();
            LoadInteger(idxName); 
            Call(XmlILMethods.GetAtomizedName);
        } 
 
        public void CallGetNameFilter(int idxFilter) {
            LoadQueryRuntime(); 
            LoadInteger(idxFilter);
            Call(XmlILMethods.GetNameFilter);
        }
 
        public void CallGetTypeFilter(XPathNodeType nodeType) {
            LoadQueryRuntime(); 
            LoadInteger((int) nodeType); 
            Call(XmlILMethods.GetTypeFilter);
        } 

        public void CallParseTagName(GenerateNameType nameType) {
            if (nameType == GenerateNameType.TagNameAndMappings) {
                Call(XmlILMethods.TagAndMappings); 
            }
            else { 
                Debug.Assert(nameType == GenerateNameType.TagNameAndNamespace); 
                Call(XmlILMethods.TagAndNamespace);
            } 
        }

        public void CallGetGlobalValue(int idxValue, Type clrType) {
            LoadQueryRuntime(); 
            LoadInteger(idxValue);
            Call(XmlILMethods.GetGlobalValue); 
            TreatAs(typeof(object), clrType); 
        }
 
        public void CallSetGlobalValue(Type clrType) {
            TreatAs(clrType, typeof(object));
            Call(XmlILMethods.SetGlobalValue);
        } 

        public void CallGetCollation(int idxName) { 
            LoadQueryRuntime(); 
            LoadInteger(idxName);
            Call(XmlILMethods.GetCollation); 
        }

        private void EnsureWriter() {
            // If write variable has not yet been initialized, do it now 
            if (!this.initWriters) {
                this.locXOut = DeclareLocal("$$$xwrtChk", typeof(XmlQueryOutput)); 
                this.initWriters = true; 
            }
        } 


        //-----------------------------------------------
        // XmlQueryContext function calls 
        //-----------------------------------------------
 
        public void CallGetParameter(string localName, string namespaceUri) { 
            LoadQueryContext();
            Emit(OpCodes.Ldstr, localName); 
            Emit(OpCodes.Ldstr, namespaceUri);
            Call(XmlILMethods.GetParam);
        }
 
        //-----------------------------------------------
        // XmlQueryOutput function calls 
        //----------------------------------------------- 

        public void CallStartTree(XPathNodeType rootType) { 
            LoadQueryOutput();
            LoadInteger((int) rootType);
            Call(XmlILMethods.StartTree);
        } 

        public void CallEndTree() { 
            LoadQueryOutput(); 
            Call(XmlILMethods.EndTree);
        } 

        public void CallWriteStartRoot() {
            // Call XmlQueryOutput.WriteStartRoot
            LoadQueryOutput(); 
            Call(XmlILMethods.StartRoot);
        } 
 
        public void CallWriteEndRoot() {
            // Call XmlQueryOutput.WriteEndRoot 
            LoadQueryOutput();
            Call(XmlILMethods.EndRoot);
        }
 
        public void CallWriteStartElement(GenerateNameType nameType, bool callChk) {
            MethodInfo meth = null; 
 
            // If runtime checks need to be made,
            if (callChk) { 
                // Then call XmlQueryOutput.WriteStartElement
                switch (nameType) {
                    case GenerateNameType.LiteralLocalName: meth = XmlILMethods.StartElemLocName; break;
                    case GenerateNameType.LiteralName: meth = XmlILMethods.StartElemLitName; break; 
                    case GenerateNameType.CopiedName: meth = XmlILMethods.StartElemCopyName; break;
                    case GenerateNameType.TagNameAndMappings: meth = XmlILMethods.StartElemMapName; break; 
                    case GenerateNameType.TagNameAndNamespace: meth = XmlILMethods.StartElemNmspName; break; 
                    case GenerateNameType.QName: meth = XmlILMethods.StartElemQName; break;
                    default: Debug.Assert(false, nameType + " is invalid here."); break; 
                }
            }
            else {
                // Else call XmlQueryOutput.WriteStartElementUnchecked 
                switch (nameType) {
                    case GenerateNameType.LiteralLocalName: meth = XmlILMethods.StartElemLocNameUn; break; 
                    case GenerateNameType.LiteralName: meth = XmlILMethods.StartElemLitNameUn; break; 
                    default: Debug.Assert(false, nameType + " is invalid here."); break;
                } 
            }

            Call(meth);
        } 

        public void CallWriteEndElement(GenerateNameType nameType, bool callChk) { 
            MethodInfo meth = null; 

            // If runtime checks need to be made, 
            if (callChk) {
                // Then call XmlQueryOutput.WriteEndElement
                meth = XmlILMethods.EndElemStackName;
            } 
            else {
                // Else call XmlQueryOutput.WriteEndElementUnchecked 
                switch (nameType) { 
                    case GenerateNameType.LiteralLocalName: meth = XmlILMethods.EndElemLocNameUn; break;
                    case GenerateNameType.LiteralName: meth = XmlILMethods.EndElemLitNameUn; break; 
                    default: Debug.Assert(false, nameType + " is invalid here."); break;
                }
            }
 
            Call(meth);
        } 
 
        public void CallStartElementContent() {
            LoadQueryOutput(); 
            Call(XmlILMethods.StartContentUn);
        }

        public void CallWriteStartAttribute(GenerateNameType nameType, bool callChk) { 
            MethodInfo meth = null;
 
            // If runtime checks need to be made, 
            if (callChk) {
                // Then call XmlQueryOutput.WriteStartAttribute 
                switch (nameType) {
                    case GenerateNameType.LiteralLocalName: meth = XmlILMethods.StartAttrLocName; break;
                    case GenerateNameType.LiteralName: meth = XmlILMethods.StartAttrLitName; break;
                    case GenerateNameType.CopiedName: meth = XmlILMethods.StartAttrCopyName; break; 
                    case GenerateNameType.TagNameAndMappings: meth = XmlILMethods.StartAttrMapName; break;
                    case GenerateNameType.TagNameAndNamespace: meth = XmlILMethods.StartAttrNmspName; break; 
                    case GenerateNameType.QName: meth = XmlILMethods.StartAttrQName; break; 
                    default: Debug.Assert(false, nameType + " is invalid here."); break;
                } 
            }
            else {
                // Else call XmlQueryOutput.WriteStartAttributeUnchecked
                switch (nameType) { 
                    case GenerateNameType.LiteralLocalName: meth = XmlILMethods.StartAttrLocNameUn; break;
                    case GenerateNameType.LiteralName: meth = XmlILMethods.StartAttrLitNameUn; break; 
                    default: Debug.Assert(false, nameType + " is invalid here."); break; 
                }
            } 

            Call(meth);
        }
 
        public void CallWriteEndAttribute(bool callChk) {
            LoadQueryOutput(); 
 
            // If runtime checks need to be made,
            if (callChk) { 
                // Then call XmlQueryOutput.WriteEndAttribute
                Call(XmlILMethods.EndAttr);
            }
            else { 
                // Else call XmlQueryOutput.WriteEndAttributeUnchecked
                Call(XmlILMethods.EndAttrUn); 
            } 
        }
 
        public void CallWriteNamespaceDecl(bool callChk) {
            // If runtime checks need to be made,
            if (callChk) {
                // Then call XmlQueryOutput.WriteNamespaceDeclaration 
                Call(XmlILMethods.NamespaceDecl);
            } 
            else { 
                // Else call XmlQueryOutput.WriteNamespaceDeclarationUnchecked
                Call(XmlILMethods.NamespaceDeclUn); 
            }
        }

        public void CallWriteString(bool disableOutputEscaping, bool callChk) { 
            // If runtime checks need to be made,
            if (callChk) { 
                // Then call XmlQueryOutput.WriteString, or XmlQueryOutput.WriteRaw 
                if (disableOutputEscaping)
                    Call(XmlILMethods.NoEntText); 
                else
                    Call(XmlILMethods.Text);
            }
            else { 
                // Else call XmlQueryOutput.WriteStringUnchecked, or XmlQueryOutput.WriteRawUnchecked
                if (disableOutputEscaping) 
                    Call(XmlILMethods.NoEntTextUn); 
                else
                    Call(XmlILMethods.TextUn); 
            }
        }

        public void CallWriteStartPI() { 
            Call(XmlILMethods.StartPI);
        } 
 
        public void CallWriteEndPI() {
            LoadQueryOutput(); 
            Call(XmlILMethods.EndPI);
        }

        public void CallWriteStartComment() { 
            LoadQueryOutput();
            Call(XmlILMethods.StartComment); 
        } 

        public void CallWriteEndComment() { 
            LoadQueryOutput();
            Call(XmlILMethods.EndComment);
        }
 

        //----------------------------------------------- 
        // Item caching methods 
        //-----------------------------------------------
 
        public void CallCacheCount(Type itemStorageType) {
            XmlILStorageMethods meth = XmlILMethods.StorageMethods[itemStorageType];
            Call(meth.IListCount);
        } 

        public void CallCacheItem(Type itemStorageType) { 
            Call(XmlILMethods.StorageMethods[itemStorageType].IListItem); 
        }
 

        //-----------------------------------------------
        // XPathItem properties and methods
        //----------------------------------------------- 

        public void CallValueAs(Type clrType) { 
            MethodInfo meth; 

            meth = XmlILMethods.StorageMethods[clrType].ValueAs; 
            if (meth == null) {
                // Call (Type) item.ValueAs(Type, null)
                LoadType(clrType);
                Emit(OpCodes.Ldnull); 
                Call(XmlILMethods.ValueAsAny);
 
                // Unbox or down-cast 
                TreatAs(typeof(object), clrType);
            } 
            else {
                // Call strongly typed ValueAs method
                Call(meth);
            } 
        }
 
 
        //-----------------------------------------------
        // XmlSortKeyAccumulator methods 
        //-----------------------------------------------

        public void AddSortKey(XmlQueryType keyType) {
            MethodInfo meth = null; 

            if (keyType == null) { 
                meth = XmlILMethods.SortKeyEmpty; 
            }
            else { 
                Debug.Assert(keyType.IsAtomicValue, "Sort key must have atomic value type.");

                switch (keyType.TypeCode) {
                    case XmlTypeCode.String: meth = XmlILMethods.SortKeyString; break; 
                    case XmlTypeCode.Decimal: meth = XmlILMethods.SortKeyDecimal; break;
                    case XmlTypeCode.Integer: meth = XmlILMethods.SortKeyInteger; break; 
                    case XmlTypeCode.Int: meth = XmlILMethods.SortKeyInt; break; 
                    case XmlTypeCode.Boolean: meth = XmlILMethods.SortKeyInt; break;
                    case XmlTypeCode.Double: meth = XmlILMethods.SortKeyDouble; break; 
                    case XmlTypeCode.DateTime: meth = XmlILMethods.SortKeyDateTime; break;

                    case XmlTypeCode.None:
                        // Empty sequence, so this path will never actually be taken 
                        Emit(OpCodes.Pop);
                        meth = XmlILMethods.SortKeyEmpty; 
                        break; 

                    case XmlTypeCode.AnyAtomicType: 
                        Debug.Assert(false, "Heterogenous sort key is not allowed.");
                        return;

                    default: 
                        Debug.Assert(false, "Sorting over datatype " + keyType.TypeCode + " is not allowed.");
                        break; 
                } 
            }
 
            Call(meth);
        }

 
        //-----------------------------------------------
        // Debugging information output 
        //----------------------------------------------- 

        ///  
        /// Begin a new variable debugging scope.
        /// 
        public void DebugStartScope() {
            this.ilgen.BeginScope(); 
        }
 
        ///  
        /// End a new debugging scope.
        ///  
        public void DebugEndScope() {
            this.ilgen.EndScope();
        }
 
        /// 
        /// Correlate the current IL generation position with the current source position. 
        ///  
        public void DebugSequencePoint(ISourceLineInfo sourceInfo) {
            Debug.Assert(this.isDebug && this.lastSourceInfo != null); 
            Debug.Assert(sourceInfo != null);

            // When emitting sequence points, be careful to always follow two rules:
            // 1. Never emit adjacent sequence points, as this messes up the debugger.  We guarantee this by 
            //    always emitting a Nop before every sequence point.
            // 2. The runtime enforces a rule that BP sequence points can only appear at zero stack depth, 
            //    or if a NOP instruction is placed before them.  We guarantee this by always emitting a Nop 
            //    before every sequence point.
            //    http://devdiv/Documents/Whidbey/CLR/CurrentSpecs/Debugging%20and%20Profiling/JIT-Determined%20Sequence%20Points.doc 
            Emit(OpCodes.Nop);
            MarkSequencePoint(sourceInfo);
        }
 
        private string  lastUriString = null;
        private string  lastFileName  = null; 
 
        // SQLBUDT 278010: debugger does not work with network paths in uri format, like file://server/share/dir/file
        private string GetFileName(ISourceLineInfo sourceInfo) { 
            string uriString = sourceInfo.Uri;
            if ((object)uriString == (object)lastUriString) {
                return lastFileName;
            } 

            lastUriString = uriString; 
            lastFileName = SourceLineInfo.GetFileName(uriString); 
            return lastFileName;
        } 

        private void MarkSequencePoint(ISourceLineInfo sourceInfo) {
            Debug.Assert(this.isDebug);
 
            // Do not emit adjacent 0xfeefee sequence points, as that slows down stepping in the debugger
            if (sourceInfo.IsNoSource && this.lastSourceInfo != null && this.lastSourceInfo.IsNoSource) { 
                return; 
            }
 
            string sourceFile = GetFileName(sourceInfo);

        #if DEBUG
            if (XmlILTrace.IsEnabled) { 
                if (sourceInfo.IsNoSource)
                    this.writerDump.WriteLine("//[no source]"); 
                else { 
                    if (sourceFile != this.sourceFile) {
                        this.sourceFile = sourceFile; 
                        this.writerDump.WriteLine("// Source File '{0}'", this.sourceFile);
                    }
                    this.writerDump.WriteLine("//[{0},{1} -- {2},{3}]", sourceInfo.StartLine, sourceInfo.StartPos, sourceInfo.EndLine, sourceInfo.EndPos);
                } 
            }
        #endif 
            ISymbolDocumentWriter symDoc = this.module.AddSourceDocument(sourceFile); 
            this.ilgen.MarkSequencePoint(symDoc, sourceInfo.StartLine, sourceInfo.StartPos, sourceInfo.EndLine, sourceInfo.EndPos);
            this.lastSourceInfo = sourceInfo; 
        }


        //----------------------------------------------- 
        // Pass through to ILGenerator
        //----------------------------------------------- 
 
        public Label DefineLabel() {
            Label lbl = this.ilgen.DefineLabel(); 

        #if DEBUG
            if (XmlILTrace.IsEnabled)
                this.symbols.Add(lbl, ++this.lblNum); 
        #endif
 
            return lbl; 
        }
 
        public void MarkLabel(Label lbl) {
            if (this.lastSourceInfo != null && !this.lastSourceInfo.IsNoSource) {
                // Emit a "no source" sequence point, otherwise the debugger would show
                // a wrong line if we jumped to this label from another place 
                DebugSequencePoint(SourceLineInfo.NoSource);
            } 
 
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("Label {0}:", this.symbols[lbl]);
        #endif

            this.ilgen.MarkLabel(lbl); 
        }
 
        public void Emit(OpCode opcode) { 
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0}", opcode.Name);
        #endif
            this.ilgen.Emit(opcode);
        } 

        public void Emit(OpCode opcode, byte byteVal) { 
        #if DEBUG 
            if (XmlILTrace.IsEnabled)
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, byteVal); 
        #endif
            this.ilgen.Emit(opcode, byteVal);
        }
 
        public void Emit(OpCode opcode, ConstructorInfo constrInfo) {
        #if DEBUG 
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, constrInfo);
        #endif 
            this.ilgen.Emit(opcode, constrInfo);
        }

        public void Emit(OpCode opcode, double dblVal) { 
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, dblVal); 
        #endif
            this.ilgen.Emit(opcode, dblVal); 
        }

        public void Emit(OpCode opcode, float fltVal) {
        #if DEBUG 
            if (XmlILTrace.IsEnabled)
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, fltVal); 
        #endif 
            this.ilgen.Emit(opcode, fltVal);
        } 

        public void Emit(OpCode opcode, FieldInfo fldInfo) {
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, fldInfo.Name);
        #endif 
            this.ilgen.Emit(opcode, fldInfo); 
        }
 
        public void Emit(OpCode opcode, short shrtVal) {
            Debug.Assert(opcode.OperandType == OperandType.ShortInlineI);
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, shrtVal);
        #endif 
            this.ilgen.Emit(opcode, shrtVal); 
        }
 
        public void Emit(OpCode opcode, int intVal) {
            Debug.Assert(opcode.OperandType == OperandType.InlineI || opcode.OperandType == OperandType.InlineVar);
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, intVal);
        #endif 
            this.ilgen.Emit(opcode, intVal); 
        }
 
        public void Emit(OpCode opcode, long longVal) {
            Debug.Assert(opcode.OperandType == OperandType.InlineI8);
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, longVal);
        #endif 
            this.ilgen.Emit(opcode, longVal); 
        }
 
        public void Emit(OpCode opcode, Label lblVal) {
            Debug.Assert(!opcode.Equals(OpCodes.Br) && !opcode.Equals(OpCodes.Br_S), "Use EmitUnconditionalBranch and be careful not to emit unverifiable code.");
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} Label {1}", opcode.Name, this.symbols[lblVal]);
        #endif 
            this.ilgen.Emit(opcode, lblVal); 
        }
 
        public void Emit(OpCode opcode, Label[] arrLabels) {
        #if DEBUG
            if (XmlILTrace.IsEnabled) {
                this.writerDump.Write("  {0, -10} (Label {1}", opcode.Name, arrLabels.Length != 0 ? this.symbols[arrLabels[0]].ToString() : ""); 
                for (int i = 1; i < arrLabels.Length; i++) {
                    this.writerDump.Write(", Label {0}", this.symbols[arrLabels[i]]); 
                } 
                this.writerDump.WriteLine(")");
            } 
        #endif
            this.ilgen.Emit(opcode, arrLabels);
        }
 
        public void Emit(OpCode opcode, LocalBuilder locBldr) {
        #if DEBUG 
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1} ({2})", opcode.Name, this.symbols[locBldr], locBldr.LocalType.Name);
        #endif 
            this.ilgen.Emit(opcode, locBldr);
        }

        public void Emit(OpCode opcode, MethodInfo methInfo) { 
            Debug.Assert(!opcode.Equals(OpCodes.Call) && !opcode.Equals(OpCodes.Callvirt), "Use Call so that debug information will be output correctly.");
        #if DEBUG 
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, methInfo.Name);
        #endif 
            this.ilgen.Emit(opcode, methInfo);
        }

        public void Emit(OpCode opcode, sbyte sbyteVal) { 
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, sbyteVal); 
        #endif
            this.ilgen.Emit(opcode, sbyteVal); 
        }

        public void Emit(OpCode opcode, string strVal) {
        #if DEBUG 
            if (XmlILTrace.IsEnabled)
                this.writerDump.WriteLine("  {0, -10} \"{1}\"", opcode.Name, strVal); 
        #endif 
            this.ilgen.Emit(opcode, strVal);
        } 

        public void Emit(OpCode opcode, Type typVal) {
        #if DEBUG
            if (XmlILTrace.IsEnabled) 
                this.writerDump.WriteLine("  {0, -10} {1}", opcode.Name, typVal);
        #endif 
            this.ilgen.Emit(opcode, typVal); 
        }
 
        /// 
        /// Unconditional branch opcodes (OpCode.Br, OpCode.Br_S) can lead to unverifiable code in the following cases:
        ///
        ///   # DEAD CODE CASE 
        ///     ldc_i4  1       # Stack depth == 1
        ///     br      Label2 
        ///   Label1: 
        ///     nop             # Dead code, so IL rules assume stack depth == 0.  This causes a verification error,
        ///                     # since next instruction has depth == 1 
        ///   Label2:
        ///     pop             # Stack depth == 1
        ///     ret
        /// 
        ///   # LATE BRANCH CASE
        ///     ldc_i4  1       # Stack depth == 1 
        ///     br      Label2 
        ///   Label1:
        ///     nop             # Not dead code, but since branch comes from below, IL rules assume stack depth = 0. 
        ///                     # This causes a verification error, since next instruction has depth == 1
        ///   Label2:
        ///     pop             # Stack depth == 1
        ///     ret 
        ///   Label3:
        ///     br      Label1  # Stack depth == 1 
        /// 
        /// This method works around the above limitations by using Brtrue or Brfalse in the following way:
        /// 
        ///     ldc_i4  1       # Since this test is always true, this is a way of creating a path to the code that
        ///     brtrue  Label   # follows the brtrue instruction.
        ///
        ///     ldc_i4  1       # Since this test is always false, this is a way of creating a path to the code that 
        ///     brfalse Label   # starts at Label.
        /// 
        /// 1. If opcode == Brtrue or Brtrue_S, then 1 will be pushed and brtrue instruction will be generated. 
        /// 2. If opcode == Brfalse or Brfalse_S, then 1 will be pushed and brfalse instruction will be generated.
        /// 3. If opcode == Br or Br_S, then a br instruction will be generated. 
        /// 
        public void EmitUnconditionalBranch(OpCode opcode, Label lblTarget) {
            if (!opcode.Equals(OpCodes.Br) && !opcode.Equals(OpCodes.Br_S)) {
                Debug.Assert(opcode.Equals(OpCodes.Brtrue) || opcode.Equals(OpCodes.Brtrue_S) || 
                             opcode.Equals(OpCodes.Brfalse) || opcode.Equals(OpCodes.Brfalse_S));
                Emit(OpCodes.Ldc_I4_1); 
            } 

        #if DEBUG 
            if (XmlILTrace.IsEnabled)
                this.writerDump.WriteLine("  {0, -10} Label {1}", opcode.Name, this.symbols[lblTarget]);
        #endif
            this.ilgen.Emit(opcode, lblTarget); 

            if (this.lastSourceInfo != null && (opcode.Equals(OpCodes.Br) || opcode.Equals(OpCodes.Br_S))) { 
                // Emit a "no source" sequence point, otherwise the following label will be preceded 
                // with a dead Nop operation, which may lead to unverifiable code (SQLBUDT 423393).
                // We are guaranteed not to emit adjacent sequence points because Br or Br_S 
                // instruction precedes this sequence point, and a Nop instruction precedes other
                // sequence points.
                MarkSequencePoint(SourceLineInfo.NoSource);
            } 
        }
    } 
} 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
                        

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