[AST] QualifiedTemplateName::getTemplateDecl cleanup.

[hokein]

Summary

This is a followup cleanup of 1234b1c6d8113d50beef5801be607ad1d502b2f7

[sammccall]

clang/lib/AST/ItaniumMangle.cpp

2206

can't this just be TN.getAsTemplateDecl() and tacked onto the next case?

clang/tools/libclang/CIndex.cpp

1463–1464

this can be handled along with the Template/UsingTemplate cases (apart from the fixme)

[hokein]

address comments

clang/include/clang/AST/TemplateName.h

public:
 
   /// Whether the template name was prefixed by the "template"
   /// keyword.
   bool hasTemplateKeyword() const { return Qualifier.getInt(); }
 
   /// Return the underlying template name.
   TemplateName getUnderlyingTemplate() const { return UnderlyingTemplate; }
 
-  /// The template declaration to which this qualified name
-  /// refers.
-  /// FIXME: remove this and use getUnderlyingTemplate() instead.
-  TemplateDecl *getTemplateDecl() const {
-    return UnderlyingTemplate.getAsTemplateDecl();
-  }
-
   void Profile(llvm::FoldingSetNodeID &ID) {
     Profile(ID, getQualifier(), hasTemplateKeyword(), UnderlyingTemplate);
   }
 
   static void Profile(llvm::FoldingSetNodeID &ID, NestedNameSpecifier *NNS,
                       bool TemplateKeyword, TemplateName TN) {
     ID.AddPointer(NNS);
     ID.AddBoolean(TemplateKeyword);

clang/lib/AST/ItaniumMangle.cpp

 ///          ::= <substitution>
 void CXXNameMangler::mangleType(TemplateName TN) {
   if (mangleSubstitution(TN))
     return;
 
   TemplateDecl *TD = nullptr;
 
   switch (TN.getKind()) {
   case TemplateName::QualifiedTemplate:
-    TD = TN.getAsQualifiedTemplateName()->getTemplateDecl();
-    goto HaveDecl;
-
   case TemplateName::UsingTemplate:
   case TemplateName::Template:
     TD = TN.getAsTemplateDecl();
     goto HaveDecl;
 
   HaveDecl:
     if (auto *TTP = dyn_cast<TemplateTemplateParmDecl>(TD))
       mangleTemplateParameter(TTP->getDepth(), TTP->getIndex());

clang/lib/AST/TemplateName.cpp

if (Decl *TemplateOrUsing = Storage.dyn_cast<Decl *>()) {
     if (UsingShadowDecl *USD = dyn_cast<UsingShadowDecl>(TemplateOrUsing))
       return cast<TemplateDecl>(USD->getTargetDecl());
 
     assert(isa<TemplateDecl>(TemplateOrUsing));
     return cast<TemplateDecl>(TemplateOrUsing);
   }
 
   if (QualifiedTemplateName *QTN = getAsQualifiedTemplateName())
-    return QTN->getTemplateDecl();
+    return QTN->getUnderlyingTemplate().getAsTemplateDecl();
 
   if (SubstTemplateTemplateParmStorage *sub = getAsSubstTemplateTemplateParm())
     return sub->getReplacement().getAsTemplateDecl();
 
   if (UsingShadowDecl *USD = getAsUsingShadowDecl())
     return cast<TemplateDecl>(USD->getTargetDecl());
 
   return nullptr;
else if (Qual == Qualified::Fully &&
                  TemplateNameDependenceScope::DependentInstantiation)
       Template->printQualifiedName(OS, Policy);
     else
       OS << *Template;
   else if (QualifiedTemplateName *QTN = getAsQualifiedTemplateName()) {
     if (Qual == Qualified::Fully &&
         getDependence() !=
             TemplateNameDependenceScope::DependentInstantiation) {
-      QTN->getTemplateDecl()->printQualifiedName(OS, Policy);
+      QTN->getUnderlyingTemplate().getAsTemplateDecl()->printQualifiedName(
+          OS, Policy);
       return;
     }
     if (Qual == Qualified::AsWritten)
       QTN->getQualifier()->print(OS, Policy);
     if (QTN->hasTemplateKeyword())
       OS << "template ";
-    OS << *QTN->getTemplateDecl();
+    OS << *QTN->getUnderlyingTemplate().getAsTemplateDecl();
   } else if (DependentTemplateName *DTN = getAsDependentTemplateName()) {
     if (Qual == Qualified::AsWritten && DTN->getQualifier())
       DTN->getQualifier()->print(OS, Policy);
     OS << "template ";
 
     if (DTN->isIdentifier())
       OS << DTN->getIdentifier()->getName();
     else

clang/lib/Sema/TreeTransform.h

 TemplateName
 TreeTransform<Derived>::TransformTemplateName(CXXScopeSpec &SS,
                                               TemplateName Name,
                                               SourceLocation NameLoc,
                                               QualType ObjectType,
                                               NamedDecl *FirstQualifierInScope,
                                               bool AllowInjectedClassName) {
   if (QualifiedTemplateName *QTN = Name.getAsQualifiedTemplateName()) {
-    TemplateDecl *Template = QTN->getTemplateDecl();
+    TemplateDecl *Template = QTN->getUnderlyingTemplate().getAsTemplateDecl();
     assert(Template && "qualified template name must refer to a template");
 
     TemplateDecl *TransTemplate
       = cast_or_null<TemplateDecl>(getDerived().TransformDecl(NameLoc,
                                                               Template));
     if (!TransTemplate)
       return TemplateName();
 

clang/tools/libclang/CIndex.cpp

bool CursorVisitor::VisitTemplateParameters(
 
   return false;
 }
 
 bool CursorVisitor::VisitTemplateName(TemplateName Name, SourceLocation Loc) {
   switch (Name.getKind()) {
   case TemplateName::Template:
   case TemplateName::UsingTemplate:
+  case TemplateName::QualifiedTemplate: // FIXME: Visit nested-name-specifier.
     return Visit(MakeCursorTemplateRef(Name.getAsTemplateDecl(), Loc, TU));
 
   case TemplateName::OverloadedTemplate:
     // Visit the overloaded template set.
     if (Visit(MakeCursorOverloadedDeclRef(Name, Loc, TU)))
       return true;
 
     return false;
 
   case TemplateName::AssumedTemplate:
     // FIXME: Visit DeclarationName?
     return false;
 
   case TemplateName::DependentTemplate:
     // FIXME: Visit nested-name-specifier.
     return false;
 
-  case TemplateName::QualifiedTemplate:
-    // FIXME: Visit nested-name-specifier.
-    return Visit(MakeCursorTemplateRef(
-        Name.getAsQualifiedTemplateName()->getTemplateDecl(), Loc, TU));
-
   case TemplateName::SubstTemplateTemplateParm:
     return Visit(MakeCursorTemplateRef(
         Name.getAsSubstTemplateTemplateParm()->getParameter(), Loc, TU));
 
   case TemplateName::SubstTemplateTemplateParmPack:
     return Visit(MakeCursorTemplateRef(
         Name.getAsSubstTemplateTemplateParmPack()->getParameterPack(), Loc,
         TU));
   }