/// <summary>
/// Calculate starting xml states that will result when iterating over and constructing an expression of the specified type.
/// </summary>
private void StartLoop(XmlQueryType typ, XmlILConstructInfo info)
{
Debug.Assert(!typ.IsSingleton);
// This is tricky, because the looping introduces a feedback loop:
// 1. Because loops may be executed many times, the beginning set of states must include the ending set of states.
// 2. Because loops may be executed 0 times, the final set of states after all looping is complete must include
// the initial set of states.
//
// +-- states-initial
// | |
// | states-begin-loop <--+
// | | |
// | +--------------+ |
// | | Construction | |
// | +--------------+ |
// | | |
// | states-end-loop ----+
// | |
// +--> states-final
// Save starting loop states
info.BeginLoopStates = this.xstates;
if (typ.MaybeMany)
{
// If transition might occur from EnumAttrs to WithinContent, then states-end might be WithinContent, which
// means states-begin needs to also include WithinContent.
if (this.xstates == PossibleXmlStates.EnumAttrs && MaybeContent(typ))
{
info.BeginLoopStates = this.xstates = PossibleXmlStates.Any;
}
}
}
/// <summary>
/// Analyze choice.
/// </summary>
protected virtual void AnalyzeChoice(QilChoice ndChoice, XmlILConstructInfo info)
{
PossibleXmlStates xstatesChoice;
int idx;
// Visit default branch; save resulting states
idx = ndChoice.Branches.Count - 1;
ndChoice.Branches[idx] = AnalyzeContent(ndChoice.Branches[idx]);
xstatesChoice = this.xstates;
// Visit all other branches
while (--idx >= 0)
{
// Restore starting states and visit the next branch
this.xstates = info.InitialStates;
ndChoice.Branches[idx] = AnalyzeContent(ndChoice.Branches[idx]);
// Choice ending states consist of combination of all branch states
if (xstatesChoice != this.xstates)
{
xstatesChoice = PossibleXmlStates.Any;
}
}
this.xstates = xstatesChoice;
}
/// <summary>
/// Recursively analyze the definition of a function.
/// </summary>
private static void AnalyzeDefinition(QilNode nd)
{
Debug.Assert(XmlILConstructInfo.Read(nd).PushToWriterLast,
"Only need to analyze expressions which will be compiled in push mode.");
switch (nd.NodeType)
{
case QilNodeType.Invoke:
// Invoke node can either be compiled as IteratorThenWriter, or Writer.
// Since IteratorThenWriter involves caching the results of the function call
// and iterating over them, .tailcall cannot be used
if (XmlILConstructInfo.Read(nd).ConstructMethod == XmlILConstructMethod.Writer)
{
OptimizerPatterns.Write(nd).AddPattern(OptimizerPatternName.TailCall);
}
break;
case QilNodeType.Loop: {
// Recursively analyze Loop return value
QilLoop ndLoop = (QilLoop)nd;
if (ndLoop.Variable.NodeType == QilNodeType.Let || !ndLoop.Variable.Binding.XmlType.MaybeMany)
{
AnalyzeDefinition(ndLoop.Body);
}
break;
}
case QilNodeType.Sequence: {
// Recursively analyze last expression in Sequence
QilList ndSeq = (QilList)nd;
if (ndSeq.Count > 0)
{
AnalyzeDefinition(ndSeq[ndSeq.Count - 1]);
}
break;
}
case QilNodeType.Choice: {
// Recursively analyze Choice branches
QilChoice ndChoice = (QilChoice)nd;
for (int i = 0; i < ndChoice.Branches.Count; i++)
{
AnalyzeDefinition(ndChoice.Branches[i]);
}
break;
}
case QilNodeType.Conditional: {
// Recursively analyze Conditional branches
QilTernary ndCond = (QilTernary)nd;
AnalyzeDefinition(ndCond.Center);
AnalyzeDefinition(ndCond.Right);
break;
}
case QilNodeType.Nop:
AnalyzeDefinition(((QilUnary)nd).Child);
break;
}
}
/// <summary>
/// Analyze loop.
/// </summary>
protected override void AnalyzeLoop(QilLoop ndLoop, XmlILConstructInfo info)
{
// Constructing attributes/namespaces in a loop can cause duplicates, namespaces after attributes, etc.
if (ndLoop.XmlType.MaybeMany)
{
CheckAttributeNamespaceConstruct(ndLoop.XmlType);
}
base.AnalyzeLoop(ndLoop, info);
}
/// <summary>
/// Analyze list.
/// </summary>
protected virtual void AnalyzeSequence(QilList ndSeq, XmlILConstructInfo info)
{
// Ensure that construct method is Writer
info.ConstructMethod = XmlILConstructMethod.Writer;
// Analyze each item in the list
for (int idx = 0; idx < ndSeq.Count; idx++)
{
ndSeq[idx] = AnalyzeContent(ndSeq[idx]);
}
}
/// <summary>
/// Perform tail-call analysis on the functions in the specified QilExpression.
/// </summary>
public static void Analyze(QilExpression qil)
{
foreach (QilFunction ndFunc in qil.FunctionList)
{
// Only analyze functions which are pushed to the writer, since otherwise code
// is generated after the call instruction in order to process cached results
if (XmlILConstructInfo.Read(ndFunc).ConstructMethod == XmlILConstructMethod.Writer)
{
AnalyzeDefinition(ndFunc.Definition);
}
}
}
/// <summary>
/// Default to worst possible construction information.
/// </summary>
private XmlILConstructInfo(QilNodeType nodeType)
{
_nodeType = nodeType;
_xstatesInitial = _xstatesFinal = PossibleXmlStates.Any;
_xstatesBeginLoop = _xstatesEndLoop = PossibleXmlStates.None;
_isNmspInScope = false;
_mightHaveNmsp = true;
_mightHaveAttrs = true;
_mightHaveDupAttrs = true;
_mightHaveNmspAfterAttrs = true;
_constrMeth = XmlILConstructMethod.Iterator;
_parentInfo = null;
}
/// <summary>
/// Calculate ending xml states that will result when iterating over and constructing an expression of the specified type.
/// </summary>
private void EndLoop(XmlQueryType typ, XmlILConstructInfo info)
{
Debug.Assert(!typ.IsSingleton);
// Save ending loop states
info.EndLoopStates = this.xstates;
// If it's possible to loop zero times, then states-final needs to include states-initial
if (typ.MaybeEmpty && info.InitialStates != this.xstates)
{
this.xstates = PossibleXmlStates.Any;
}
}
/// <summary>
/// Analyze copying items.
/// </summary>
protected override void AnalyzeCopy(QilNode ndCopy, XmlILConstructInfo info)
{
if (ndCopy.NodeType == QilNodeType.AttributeCtor)
{
AnalyzeAttributeCtor(ndCopy as QilBinary, info);
}
else
{
CheckAttributeNamespaceConstruct(ndCopy.XmlType);
}
base.AnalyzeCopy(ndCopy, info);
}
/// <summary>
/// Create and initialize XmlILConstructInfo annotation for the specified node.
/// </summary>
public static XmlILConstructInfo Write(QilNode nd)
{
XmlILAnnotation ann = XmlILAnnotation.Write(nd);
XmlILConstructInfo constrInfo = ann.ConstructInfo;
if (constrInfo == null || constrInfo._isReadOnly)
{
constrInfo = new XmlILConstructInfo(nd.NodeType);
ann.ConstructInfo = constrInfo;
}
return(constrInfo);
}
/// <summary>
/// Analyze copying items.
/// </summary>
protected override void AnalyzeCopy(QilNode ndCopy, XmlILConstructInfo info)
{
if (ndCopy.NodeType == QilNodeType.AttributeCtor)
{
QilBinary?binaryNode = ndCopy as QilBinary;
Debug.Assert(binaryNode != null);
AnalyzeAttributeCtor(binaryNode, info);
}
else
{
CheckAttributeNamespaceConstruct(ndCopy.XmlType !);
}
base.AnalyzeCopy(ndCopy, info);
}
/// <summary>
/// Analyze attribute constructor.
/// </summary>
private void AnalyzeAttributeCtor(QilBinary ndAttr, XmlILConstructInfo info)
{
if (ndAttr.Left.NodeType == QilNodeType.LiteralQName)
{
QilName?ndName = ndAttr.Left as QilName;
Debug.Assert(ndName != null);
XmlQualifiedName qname;
int idx;
// This attribute might be constructed on the parent element
this.parentInfo !.MightHaveAttributes = true;
// Check to see whether this attribute is a duplicate of a previous attribute
if (!this.parentInfo.MightHaveDuplicateAttributes)
{
qname = new XmlQualifiedName(_attrNames.Add(ndName.LocalName), _attrNames.Add(ndName.NamespaceUri));
for (idx = 0; idx < _dupAttrs.Count; idx++)
{
XmlQualifiedName qnameDup = (XmlQualifiedName)_dupAttrs[idx] !;
if ((object)qnameDup.Name == (object)qname.Name && (object)qnameDup.Namespace == (object)qname.Namespace)
{
// A duplicate attribute has been encountered
this.parentInfo.MightHaveDuplicateAttributes = true;
}
}
if (idx >= _dupAttrs.Count)
{
// This is not a duplicate attribute, so add it to the set
_dupAttrs.Add(qname);
}
}
// The attribute's namespace might need to be declared
if (!info.IsNamespaceInScope)
{
this.parentInfo.MightHaveNamespaces = true;
}
}
else
{
// Attribute prefix and namespace are not known at compile-time
CheckAttributeNamespaceConstruct(ndAttr.XmlType !);
}
}
/// <summary>
/// Get ConstructInfo annotation for the specified node. Lazily create if necessary.
/// </summary>
public static XmlILConstructInfo Read(QilNode nd) {
XmlILAnnotation ann = nd.Annotation as XmlILAnnotation;
XmlILConstructInfo constrInfo = (ann != null) ? ann.ConstructInfo : null;
if (constrInfo == null) {
if (Default == null) {
constrInfo = new XmlILConstructInfo(QilNodeType.Unknown);
constrInfo.isReadOnly = true;
Default = constrInfo;
}
else {
constrInfo = Default;
}
}
return constrInfo;
}
/// <summary>
/// Analyze the content argument of the ElementCtor. Try to eliminate as many runtime checks as possible,
/// both for the ElementCtor and for content constructors.
/// </summary>
public override QilNode Analyze(QilNode ndElem, QilNode ndContent)
{
Debug.Assert(ndElem.NodeType == QilNodeType.ElementCtor);
this.parentInfo = XmlILConstructInfo.Write(ndElem);
// Start by assuming that these properties are false (they default to true, but analyzer might be able to
// prove they are really false).
this.parentInfo.MightHaveNamespacesAfterAttributes = false;
this.parentInfo.MightHaveAttributes = false;
this.parentInfo.MightHaveDuplicateAttributes = false;
// The element's namespace might need to be declared
this.parentInfo.MightHaveNamespaces = !this.parentInfo.IsNamespaceInScope;
// Clear list of duplicate attributes
_dupAttrs.Clear();
return(base.Analyze(ndElem, ndContent));
}
/// <summary>
/// Analyze loop.
/// </summary>
protected virtual void AnalyzeLoop(QilLoop ndLoop, XmlILConstructInfo info)
{
XmlQueryType typ = ndLoop.XmlType;
// Ensure that construct method is Writer
info.ConstructMethod = XmlILConstructMethod.Writer;
if (!typ.IsSingleton)
{
StartLoop(typ, info);
}
// Body constructs content
ndLoop.Body = AnalyzeContent(ndLoop.Body);
if (!typ.IsSingleton)
{
EndLoop(typ, info);
}
}
/// <summary>
/// Analyze conditional.
/// </summary>
protected virtual void AnalyzeConditional(QilTernary ndCond, XmlILConstructInfo info)
{
PossibleXmlStates xstatesTrue;
// Ensure that construct method is Writer
info.ConstructMethod = XmlILConstructMethod.Writer;
// Visit true branch; save resulting states
ndCond.Center = AnalyzeContent(ndCond.Center);
xstatesTrue = this.xstates;
// Restore starting states and visit false branch
this.xstates = info.InitialStates;
ndCond.Right = AnalyzeContent(ndCond.Right);
// Conditional ending states consist of combination of true and false branch states
if (xstatesTrue != this.xstates)
{
this.xstates = PossibleXmlStates.Any;
}
}
/// <summary>
/// Get ConstructInfo annotation for the specified node. Lazily create if necessary.
/// </summary>
public static XmlILConstructInfo Read(QilNode nd)
{
XmlILAnnotation ann = nd.Annotation as XmlILAnnotation;
XmlILConstructInfo constrInfo = (ann != null) ? ann.ConstructInfo : null;
if (constrInfo == null)
{
if (s_default == null)
{
constrInfo = new XmlILConstructInfo(QilNodeType.Unknown);
constrInfo._isReadOnly = true;
s_default = constrInfo;
}
else
{
constrInfo = s_default;
}
}
return(constrInfo);
}
/// <summary>
/// Analyze copying items.
/// </summary>
protected virtual void AnalyzeCopy(QilNode ndCopy, XmlILConstructInfo info)
{
XmlQueryType typ = ndCopy.XmlType;
// Copying item(s) to output involves looping if there is not exactly one item in the sequence
if (!typ.IsSingleton)
{
StartLoop(typ, info);
}
// Determine state transitions that may take place
if (MaybeContent(typ))
{
if (MaybeAttrNmsp(typ))
{
// Node might be Attr/Nmsp or non-Attr/Nmsp, so transition from EnumAttrs to WithinContent *may* occur
if (this.xstates == PossibleXmlStates.EnumAttrs)
{
this.xstates = PossibleXmlStates.Any;
}
}
else
{
// Node is guaranteed not to be Attr/Nmsp, so transition to WithinContent will occur if starting
// state is EnumAttrs or if constructing within an element (guaranteed to be in EnumAttrs or WithinContent state)
if (this.xstates == PossibleXmlStates.EnumAttrs || this.withinElem)
{
this.xstates = PossibleXmlStates.WithinContent;
}
}
}
if (!typ.IsSingleton)
{
EndLoop(typ, info);
}
}
/// <summary>
/// Analyze loop.
/// </summary>
protected virtual void AnalyzeLoop(QilLoop ndLoop, XmlILConstructInfo info) {
XmlQueryType typ = ndLoop.XmlType;
// Ensure that construct method is Writer
info.ConstructMethod = XmlILConstructMethod.Writer;
if (!typ.IsSingleton)
StartLoop(typ, info);
// Body constructs content
ndLoop.Body = AnalyzeContent(ndLoop.Body);
if (!typ.IsSingleton)
EndLoop(typ, info);
}
/// <summary>
/// Analyze copying items.
/// </summary>
protected override void AnalyzeCopy(QilNode ndCopy, XmlILConstructInfo info) {
if (ndCopy.NodeType == QilNodeType.AttributeCtor) {
AnalyzeAttributeCtor(ndCopy as QilBinary, info);
}
else {
CheckAttributeNamespaceConstruct(ndCopy.XmlType);
}
base.AnalyzeCopy(ndCopy, info);
}
/// <summary>
/// Analyze list.
/// </summary>
protected virtual void AnalyzeSequence(QilList ndSeq, XmlILConstructInfo info) {
// Ensure that construct method is Writer
info.ConstructMethod = XmlILConstructMethod.Writer;
// Analyze each item in the list
for (int idx = 0; idx < ndSeq.Count; idx++)
ndSeq[idx] = AnalyzeContent(ndSeq[idx]);
}
/// <summary>
/// Analyze conditional.
/// </summary>
protected virtual void AnalyzeConditional(QilTernary ndCond, XmlILConstructInfo info) {
PossibleXmlStates xstatesTrue;
// Ensure that construct method is Writer
info.ConstructMethod = XmlILConstructMethod.Writer;
// Visit true branch; save resulting states
ndCond.Center = AnalyzeContent(ndCond.Center);
xstatesTrue = this.xstates;
// Restore starting states and visit false branch
this.xstates = info.InitialStates;
ndCond.Right = AnalyzeContent(ndCond.Right);
// Conditional ending states consist of combination of true and false branch states
if (xstatesTrue != this.xstates)
this.xstates = PossibleXmlStates.Any;
}
/// <summary>
/// Returns true if the specified element should cache attributes.
/// </summary>
private bool ElementCachesAttributes(XmlILConstructInfo info)
{
// Attributes will be cached if namespaces might be constructed after the attributes
return info.MightHaveDuplicateAttributes || info.MightHaveNamespacesAfterAttributes;
}
/// <summary>
/// Analyze choice.
/// </summary>
protected virtual void AnalyzeChoice(QilChoice ndChoice, XmlILConstructInfo info) {
PossibleXmlStates xstatesChoice;
int idx;
// Visit default branch; save resulting states
idx = ndChoice.Branches.Count - 1;
ndChoice.Branches[idx] = AnalyzeContent(ndChoice.Branches[idx]);
xstatesChoice = this.xstates;
// Visit all other branches
while (--idx >= 0) {
// Restore starting states and visit the next branch
this.xstates = info.InitialStates;
ndChoice.Branches[idx] = AnalyzeContent(ndChoice.Branches[idx]);
// Choice ending states consist of combination of all branch states
if (xstatesChoice != this.xstates)
xstatesChoice = PossibleXmlStates.Any;
}
this.xstates = xstatesChoice;
}
/// <summary>
/// Analyze loop.
/// </summary>
protected override void AnalyzeLoop(QilLoop ndLoop, XmlILConstructInfo info) {
// Constructing attributes/namespaces in a loop can cause duplicates, namespaces after attributes, etc.
if (ndLoop.XmlType.MaybeMany)
CheckAttributeNamespaceConstruct(ndLoop.XmlType);
base.AnalyzeLoop(ndLoop, info);
}
/// <summary>
/// Analyze copying items.
/// </summary>
protected virtual void AnalyzeCopy(QilNode ndCopy, XmlILConstructInfo info) {
XmlQueryType typ = ndCopy.XmlType;
// Copying item(s) to output involves looping if there is not exactly one item in the sequence
if (!typ.IsSingleton)
StartLoop(typ, info);
// Determine state transitions that may take place
if (MaybeContent(typ)) {
if (MaybeAttrNmsp(typ)) {
// Node might be Attr/Nmsp or non-Attr/Nmsp, so transition from EnumAttrs to WithinContent *may* occur
if (this.xstates == PossibleXmlStates.EnumAttrs)
this.xstates = PossibleXmlStates.Any;
}
else {
// Node is guaranteed not to be Attr/Nmsp, so transition to WithinContent will occur if starting
// state is EnumAttrs or if constructing within an element (guaranteed to be in EnumAttrs or WithinContent state)
if (this.xstates == PossibleXmlStates.EnumAttrs || this.withinElem)
this.xstates = PossibleXmlStates.WithinContent;
}
}
if (!typ.IsSingleton)
EndLoop(typ, info);
}
/// <summary>
/// Recursively analyze content. Return "nd" or a replacement for it.
/// </summary>
protected virtual QilNode AnalyzeContent(QilNode nd)
{
XmlILConstructInfo info;
QilNode ndChild;
// Handle special node-types that are replaced
switch (nd.NodeType)
{
case QilNodeType.For:
case QilNodeType.Let:
case QilNodeType.Parameter:
// Iterator references are shared and cannot be annotated directly with ConstructInfo,
// so wrap them with Nop node.
nd = this.fac.Nop(nd);
break;
}
// Get node's ConstructInfo annotation
info = XmlILConstructInfo.Write(nd);
// Set node's guaranteed parent constructor
info.ParentInfo = this.parentInfo;
// Construct all content using the Writer
info.PushToWriterLast = true;
// Set states that are possible before expression is constructed
info.InitialStates = this.xstates;
switch (nd.NodeType)
{
case QilNodeType.Loop: AnalyzeLoop(nd as QilLoop, info); break;
case QilNodeType.Sequence: AnalyzeSequence(nd as QilList, info); break;
case QilNodeType.Conditional: AnalyzeConditional(nd as QilTernary, info); break;
case QilNodeType.Choice: AnalyzeChoice(nd as QilChoice, info); break;
case QilNodeType.Error:
case QilNodeType.Warning:
// Ensure that construct method is Writer
info.ConstructMethod = XmlILConstructMethod.Writer;
break;
case QilNodeType.Nop:
ndChild = (nd as QilUnary).Child;
switch (ndChild.NodeType)
{
case QilNodeType.For:
case QilNodeType.Let:
case QilNodeType.Parameter:
// Copy iterator items as content
AnalyzeCopy(nd, info);
break;
default:
// Ensure that construct method is Writer and recursively analyze content
info.ConstructMethod = XmlILConstructMethod.Writer;
AnalyzeContent(ndChild);
break;
}
break;
default:
AnalyzeCopy(nd, info);
break;
}
// Set states that are possible after expression is constructed
info.FinalStates = this.xstates;
return(nd);
}
/// <summary>
/// Return true if a runtime check needs to be made in order to transition into the EnumAttrs state.
/// </summary>
private bool CheckEnumAttrs(XmlILConstructInfo info)
{
switch (info.InitialStates)
{
case PossibleXmlStates.WithinSequence:
case PossibleXmlStates.EnumAttrs:
// Transition to EnumAttrs can be ensured at compile-time
return false;
}
return true;
}
/// <summary>
/// Perform analysis on the specified constructor and its content. Return the ndContent that was passed in,
/// or a replacement.
/// </summary>
public virtual QilNode Analyze(QilNode ndConstr, QilNode ndContent)
{
if (ndConstr == null)
{
// Root expression is analyzed
this.parentInfo = null;
this.xstates = PossibleXmlStates.WithinSequence;
this.withinElem = false;
Debug.Assert(ndContent != null);
ndContent = AnalyzeContent(ndContent);
}
else
{
this.parentInfo = XmlILConstructInfo.Write(ndConstr);
if (ndConstr.NodeType == QilNodeType.Function)
{
// Results of function should be pushed to writer
this.parentInfo.ConstructMethod = XmlILConstructMethod.Writer;
// Start with PossibleXmlStates.None and then add additional possible starting states
PossibleXmlStates xstates = PossibleXmlStates.None;
foreach (XmlILConstructInfo infoCaller in this.parentInfo.CallersInfo)
{
if (xstates == PossibleXmlStates.None)
{
xstates = infoCaller.InitialStates;
}
else if (xstates != infoCaller.InitialStates)
{
xstates = PossibleXmlStates.Any;
}
// Function's results are pushed to Writer, so make sure that Invoke nodes' construct methods match
infoCaller.PushToWriterFirst = true;
}
this.parentInfo.InitialStates = xstates;
}
else
{
// Build a standalone tree, with this constructor as its root
if (ndConstr.NodeType != QilNodeType.Choice)
{
this.parentInfo.InitialStates = this.parentInfo.FinalStates = PossibleXmlStates.WithinSequence;
}
// Don't stream Rtf; fully cache the Rtf and copy it into any containing tree in order to simplify XmlILVisitor.VisitRtfCtor
if (ndConstr.NodeType != QilNodeType.RtfCtor)
{
this.parentInfo.ConstructMethod = XmlILConstructMethod.WriterThenIterator;
}
}
// Set withinElem = true if analyzing element content
this.withinElem = (ndConstr.NodeType == QilNodeType.ElementCtor);
switch (ndConstr.NodeType)
{
case QilNodeType.DocumentCtor: this.xstates = PossibleXmlStates.WithinContent; break;
case QilNodeType.ElementCtor: this.xstates = PossibleXmlStates.EnumAttrs; break;
case QilNodeType.AttributeCtor: this.xstates = PossibleXmlStates.WithinAttr; break;
case QilNodeType.NamespaceDecl: Debug.Assert(ndContent == null); break;
case QilNodeType.TextCtor: Debug.Assert(ndContent == null); break;
case QilNodeType.RawTextCtor: Debug.Assert(ndContent == null); break;
case QilNodeType.CommentCtor: this.xstates = PossibleXmlStates.WithinComment; break;
case QilNodeType.PICtor: this.xstates = PossibleXmlStates.WithinPI; break;
case QilNodeType.XsltCopy: this.xstates = PossibleXmlStates.Any; break;
case QilNodeType.XsltCopyOf: Debug.Assert(ndContent == null); break;
case QilNodeType.Function: this.xstates = this.parentInfo.InitialStates; break;
case QilNodeType.RtfCtor: this.xstates = PossibleXmlStates.WithinContent; break;
case QilNodeType.Choice: this.xstates = PossibleXmlStates.Any; break;
default: Debug.Assert(false, ndConstr.NodeType + " is not handled by XmlILStateAnalyzer."); break;
}
if (ndContent != null)
{
ndContent = AnalyzeContent(ndContent);
}
if (ndConstr.NodeType == QilNodeType.Choice)
{
AnalyzeChoice(ndConstr as QilChoice, this.parentInfo);
}
// Since Function will never be another node's content, set its final states here
if (ndConstr.NodeType == QilNodeType.Function)
{
this.parentInfo.FinalStates = this.xstates;
}
}
return(ndContent);
}
/// <summary>
/// Determine whether an ElementCtor, AttributeCtor, or NamespaceDecl's namespace is already declared. If it is,
/// set the IsNamespaceInScope property to True. Otherwise, add the namespace to the set of in-scope namespaces if
/// addInScopeNmsp is True. Return false if the name is computed or is invalid.
/// </summary>
private bool CheckNamespaceInScope(QilBinary nd)
{
QilName ndName;
string prefix, ns, prefixExisting, nsExisting;
XPathNodeType nodeType;
switch (nd.NodeType)
{
case QilNodeType.ElementCtor:
case QilNodeType.AttributeCtor:
ndName = nd.Left as QilName;
if (ndName != null)
{
prefix = ndName.Prefix;
ns = ndName.NamespaceUri;
nodeType = (nd.NodeType == QilNodeType.ElementCtor) ? XPathNodeType.Element : XPathNodeType.Attribute;
break;
}
// Not a literal name, so return false
return(false);
default:
Debug.Assert(nd.NodeType == QilNodeType.NamespaceDecl);
prefix = (string)(QilLiteral)nd.Left;
ns = (string)(QilLiteral)nd.Right;
nodeType = XPathNodeType.Namespace;
break;
}
// Attribute with null namespace and xmlns:xml are always in-scope
if (nd.NodeType == QilNodeType.AttributeCtor && ns.Length == 0 ||
prefix == "xml" && ns == XmlReservedNs.NsXml)
{
XmlILConstructInfo.Write(nd).IsNamespaceInScope = true;
return(true);
}
// Don't process names that are invalid
if (!ValidateNames.ValidateName(prefix, string.Empty, ns, nodeType, ValidateNames.Flags.CheckPrefixMapping))
{
return(false);
}
// Atomize names
prefix = _nsmgr.NameTable.Add(prefix);
ns = _nsmgr.NameTable.Add(ns);
// Determine whether namespace is already in-scope
for (int iNmsp = 0; iNmsp < _cntNmsp; iNmsp++)
{
_nsmgr.GetNamespaceDeclaration(iNmsp, out prefixExisting, out nsExisting);
// If prefix is already declared,
if ((object)prefix == (object)prefixExisting)
{
// Then if the namespace is the same, this namespace is redundant
if ((object)ns == (object)nsExisting)
{
XmlILConstructInfo.Write(nd).IsNamespaceInScope = true;
}
// Else quit searching, because any further matching prefixes will be hidden (not in-scope)
Debug.Assert(nd.NodeType != QilNodeType.NamespaceDecl || !_nsmgr.HasNamespace(prefix) || _nsmgr.LookupNamespace(prefix) == ns,
"Compilers must ensure that namespace declarations do not conflict with the namespace used by the element constructor.");
break;
}
}
// If not in-scope, then add if it's allowed
if (_addInScopeNmsp)
{
_nsmgr.AddNamespace(prefix, ns);
_cntNmsp++;
}
return(true);
}
/// <summary>
/// Create and initialize XmlILConstructInfo annotation for the specified node.
/// </summary>
public static XmlILConstructInfo Write(QilNode nd) {
XmlILAnnotation ann = XmlILAnnotation.Write(nd);
XmlILConstructInfo constrInfo = ann.ConstructInfo;
if (constrInfo == null || constrInfo.isReadOnly) {
constrInfo = new XmlILConstructInfo(nd.NodeType);
ann.ConstructInfo = constrInfo;
}
return constrInfo;
}
/// <summary>
/// Perform analysis on the specified constructor and its content. Return the ndContent that was passed in,
/// or a replacement.
/// </summary>
public virtual QilNode Analyze(QilNode ndConstr, QilNode ndContent) {
if (ndConstr == null) {
// Root expression is analyzed
this.parentInfo = null;
this.xstates = PossibleXmlStates.WithinSequence;
this.withinElem = false;
Debug.Assert(ndContent != null);
ndContent = AnalyzeContent(ndContent);
}
else {
this.parentInfo = XmlILConstructInfo.Write(ndConstr);
if (ndConstr.NodeType == QilNodeType.Function) {
// Results of function should be pushed to writer
this.parentInfo.ConstructMethod = XmlILConstructMethod.Writer;
// Start with PossibleXmlStates.None and then add additional possible starting states
PossibleXmlStates xstates = PossibleXmlStates.None;
foreach (XmlILConstructInfo infoCaller in this.parentInfo.CallersInfo) {
if (xstates == PossibleXmlStates.None) {
xstates = infoCaller.InitialStates;
}
else if (xstates != infoCaller.InitialStates) {
xstates = PossibleXmlStates.Any;
}
// Function's results are pushed to Writer, so make sure that Invoke nodes' construct methods match
infoCaller.PushToWriterFirst = true;
}
this.parentInfo.InitialStates = xstates;
}
else {
// Build a standalone tree, with this constructor as its root
if (ndConstr.NodeType != QilNodeType.Choice)
this.parentInfo.InitialStates = this.parentInfo.FinalStates = PossibleXmlStates.WithinSequence;
// Don't stream Rtf; fully cache the Rtf and copy it into any containing tree in order to simplify XmlILVisitor.VisitRtfCtor
if (ndConstr.NodeType != QilNodeType.RtfCtor)
this.parentInfo.ConstructMethod = XmlILConstructMethod.WriterThenIterator;
}
// Set withinElem = true if analyzing element content
this.withinElem = (ndConstr.NodeType == QilNodeType.ElementCtor);
switch (ndConstr.NodeType) {
case QilNodeType.DocumentCtor: this.xstates = PossibleXmlStates.WithinContent; break;
case QilNodeType.ElementCtor: this.xstates = PossibleXmlStates.EnumAttrs; break;
case QilNodeType.AttributeCtor: this.xstates = PossibleXmlStates.WithinAttr; break;
case QilNodeType.NamespaceDecl: Debug.Assert(ndContent == null); break;
case QilNodeType.TextCtor: Debug.Assert(ndContent == null); break;
case QilNodeType.RawTextCtor: Debug.Assert(ndContent == null); break;
case QilNodeType.CommentCtor: this.xstates = PossibleXmlStates.WithinComment; break;
case QilNodeType.PICtor: this.xstates = PossibleXmlStates.WithinPI; break;
case QilNodeType.XsltCopy: this.xstates = PossibleXmlStates.Any; break;
case QilNodeType.XsltCopyOf: Debug.Assert(ndContent == null); break;
case QilNodeType.Function: this.xstates = this.parentInfo.InitialStates; break;
case QilNodeType.RtfCtor: this.xstates = PossibleXmlStates.WithinContent; break;
case QilNodeType.Choice: this.xstates = PossibleXmlStates.Any; break;
default: Debug.Assert(false, ndConstr.NodeType + " is not handled by XmlILStateAnalyzer."); break;
}
if (ndContent != null)
ndContent = AnalyzeContent(ndContent);
if (ndConstr.NodeType == QilNodeType.Choice)
AnalyzeChoice(ndConstr as QilChoice, this.parentInfo);
// Since Function will never be another node's content, set its final states here
if (ndConstr.NodeType == QilNodeType.Function)
this.parentInfo.FinalStates = this.xstates;
}
return ndContent;
}
/// <summary>
/// Analyze attribute constructor.
/// </summary>
private void AnalyzeAttributeCtor(QilBinary ndAttr, XmlILConstructInfo info) {
if (ndAttr.Left.NodeType == QilNodeType.LiteralQName) {
QilName ndName = ndAttr.Left as QilName;
XmlQualifiedName qname;
int idx;
// This attribute might be constructed on the parent element
this.parentInfo.MightHaveAttributes = true;
// Check to see whether this attribute is a duplicate of a previous attribute
if (!this.parentInfo.MightHaveDuplicateAttributes) {
qname = new XmlQualifiedName(this.attrNames.Add(ndName.LocalName), this.attrNames.Add(ndName.NamespaceUri));
for (idx = 0; idx < this.dupAttrs.Count; idx++) {
XmlQualifiedName qnameDup = (XmlQualifiedName) this.dupAttrs[idx];
if ((object) qnameDup.Name == (object) qname.Name && (object) qnameDup.Namespace == (object) qname.Namespace) {
// A duplicate attribute has been encountered
this.parentInfo.MightHaveDuplicateAttributes = true;
}
}
if (idx >= this.dupAttrs.Count) {
// This is not a duplicate attribute, so add it to the set
this.dupAttrs.Add(qname);
}
}
// The attribute's namespace might need to be declared
if (!info.IsNamespaceInScope)
this.parentInfo.MightHaveNamespaces = true;
}
else {
// Attribute prefix and namespace are not known at compile-time
CheckAttributeNamespaceConstruct(ndAttr.XmlType);
}
}
/// <summary>
/// Default to worst possible construction information.
/// </summary>
private XmlILConstructInfo(QilNodeType nodeType) {
this.nodeType = nodeType;
this.xstatesInitial = this.xstatesFinal = PossibleXmlStates.Any;
this.xstatesBeginLoop = this.xstatesEndLoop = PossibleXmlStates.None;
this.isNmspInScope = false;
this.mightHaveNmsp = true;
this.mightHaveAttrs = true;
this.mightHaveDupAttrs = true;
this.mightHaveNmspAfterAttrs = true;
this.constrMeth = XmlILConstructMethod.Iterator;
this.parentInfo = null;
}
/// <summary>
/// Calculate starting xml states that will result when iterating over and constructing an expression of the specified type.
/// </summary>
private void StartLoop(XmlQueryType typ, XmlILConstructInfo info) {
Debug.Assert(!typ.IsSingleton);
// This is tricky, because the looping introduces a feedback loop:
// 1. Because loops may be executed many times, the beginning set of states must include the ending set of states.
// 2. Because loops may be executed 0 times, the final set of states after all looping is complete must include
// the initial set of states.
//
// +-- states-initial
// | |
// | states-begin-loop <--+
// | | |
// | +--------------+ |
// | | Construction | |
// | +--------------+ |
// | | |
// | states-end-loop ----+
// | |
// +--> states-final
// Save starting loop states
info.BeginLoopStates = this.xstates;
if (typ.MaybeMany) {
// If transition might occur from EnumAttrs to WithinContent, then states-end might be WithinContent, which
// means states-begin needs to also include WithinContent.
if (this.xstates == PossibleXmlStates.EnumAttrs && MaybeContent(typ))
info.BeginLoopStates = this.xstates = PossibleXmlStates.Any;
}
}
/// <summary>
/// Returns true if the specified node's owner element might have local namespaces added to it
/// after attributes have already been added.
/// </summary>
private bool MightHaveNamespacesAfterAttributes(XmlILConstructInfo info)
{
// Get parent element
if (info != null)
info = info.ParentElementInfo;
// If a parent element has not been statically identified, then assume that the runtime
// element will have namespaces added after attributes.
if (info == null)
return true;
return info.MightHaveNamespacesAfterAttributes;
}
/// <summary>
/// Calculate ending xml states that will result when iterating over and constructing an expression of the specified type.
/// </summary>
private void EndLoop(XmlQueryType typ, XmlILConstructInfo info) {
Debug.Assert(!typ.IsSingleton);
// Save ending loop states
info.EndLoopStates = this.xstates;
// If it's possible to loop zero times, then states-final needs to include states-initial
if (typ.MaybeEmpty && info.InitialStates != this.xstates)
this.xstates = PossibleXmlStates.Any;
}