Started implementing variable templates. Top level declarations should be fully supported, up to some limitations documented as FIXMEs or TODO. Static data member templates work very partially. Static data member templates of class templates need particular attention...

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@187762 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 27 insertions, 8 deletions

diff --git a/include/clang/AST/ASTContext.h b/include/clang/AST/ASTContext.h
index a686f3378f..405043a1db 100644
--- a/include/clang/AST/ASTContext.h
+++ b/include/clang/AST/ASTContext.h
@@ -271,13 +271,25 @@ class ASTContext : public RefCountedBase<ASTContext> {
   /// wasting space in the Decl class.
   llvm::DenseMap<const Decl*, AttrVec*> DeclAttrs;
 
-  /// \brief Keeps track of the static data member templates from which
-  /// static data members of class template specializations were instantiated.
+public:
+  /// \brief A type synonym for the TemplateOrInstantiation mapping.
+  typedef llvm::PointerUnion<VarTemplateDecl *, MemberSpecializationInfo *>
+  TemplateOrSpecializationInfo;
+
+private:
+
+  /// \brief A mapping to contain the template or declaration that
+  /// a variable declaration describes or was instantiated from,
+  /// respectively.
   ///
-  /// This data structure stores the mapping from instantiations of static
-  /// data members to the static data member representations within the
-  /// class template from which they were instantiated along with the kind
-  /// of instantiation or specialization (a TemplateSpecializationKind - 1).
+  /// For non-templates, this value will be NULL. For variable
+  /// declarations that describe a variable template, this will be a
+  /// pointer to a VarTemplateDecl. For static data members
+  /// of class template specializations, this will be the
+  /// MemberSpecializationInfo referring to the member variable that was
+  /// instantiated or specialized. Thus, the mapping will keep track of
+  /// the static data member templates from which static data members of
+  /// class template specializations were instantiated.
   ///
   /// Given the following example:
   ///
@@ -296,8 +308,8 @@ class ASTContext : public RefCountedBase<ASTContext> {
   /// This mapping will contain an entry that maps from the VarDecl for
   /// X<int>::value to the corresponding VarDecl for X<T>::value (within the
   /// class template X) and will be marked TSK_ImplicitInstantiation.
-  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *> 
-    InstantiatedFromStaticDataMember;
+  llvm::DenseMap<const VarDecl *, TemplateOrSpecializationInfo>
+  TemplateOrInstantiation;
 
   /// \brief Keeps track of the declaration from which a UsingDecl was
   /// created during instantiation.
@@ -606,9 +618,13 @@ public:
   /// \brief If this variable is an instantiated static data member of a
   /// class template specialization, returns the templated static data member
   /// from which it was instantiated.
+  // FIXME: Remove ?
   MemberSpecializationInfo *getInstantiatedFromStaticDataMember(
                                                            const VarDecl *Var);
 
+  TemplateOrSpecializationInfo
+  getTemplateOrSpecializationInfo(const VarDecl *Var);
+
   FunctionDecl *getClassScopeSpecializationPattern(const FunctionDecl *FD);
 
   void setClassScopeSpecializationPattern(FunctionDecl *FD,
@@ -620,6 +636,9 @@ public:
                                            TemplateSpecializationKind TSK,
                         SourceLocation PointOfInstantiation = SourceLocation());
 
+  void setTemplateOrSpecializationInfo(VarDecl *Inst,
+                                       TemplateOrSpecializationInfo TSI);
+
   /// \brief If the given using decl \p Inst is an instantiation of a
   /// (possibly unresolved) using decl from a template instantiation,
   /// return it.