Eliminate QualifiedDeclRefExpr, which captured the notion of a

qualified reference to a declaration that is not a non-static data
member or non-static member function, e.g., 

  namespace N { int i; }
  int j = N::i;

Instead, extend DeclRefExpr to optionally store the qualifier. Most
clients won't see or care about the difference (since
QualifierDeclRefExpr inherited DeclRefExpr). However, this reduces the
number of top-level expression types that clients need to cope with,
brings the implementation of DeclRefExpr into line with MemberExpr,
and simplifies and unifies our handling of declaration references.

Extended DeclRefExpr to (optionally) store explicitly-specified
template arguments. This occurs when naming a declaration via a
template-id (which will be stored in a TemplateIdRefExpr) that,
following template argument deduction and (possibly) overload
resolution, is replaced with a DeclRefExpr that refers to a template
specialization but maintains the template arguments as written.

llvm-svn: 84962

1 files changed, 34 insertions, 50 deletions

diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h
index dec94994a8a..94a0e11ec8e 100644
--- a/clang/lib/Sema/TreeTransform.h
+++ b/clang/lib/Sema/TreeTransform.h
@@ -781,10 +781,15 @@ public:
   ///
   /// By default, performs semantic analysis to build the new expression.
   /// Subclasses may override this routine to provide different behavior.
-  OwningExprResult RebuildDeclRefExpr(NamedDecl *ND, SourceLocation Loc) {
+  OwningExprResult RebuildDeclRefExpr(NestedNameSpecifier *Qualifier,
+                                      SourceRange QualifierRange,
+                                      NamedDecl *ND, SourceLocation Loc) {
+    CXXScopeSpec SS;
+    SS.setScopeRep(Qualifier);
+    SS.setRange(QualifierRange);
     return getSema().BuildDeclarationNameExpr(Loc, ND,
                                               /*FIXME:*/false,
-                                              /*SS=*/0,
+                                              &SS,
                                               /*FIXME:*/false);
   }
 
@@ -1392,26 +1397,6 @@ public:
                                          T.getAsOpaquePtr(), RParenLoc);
   }
 
-  /// \brief Build a new qualified declaration reference expression.
-  ///
-  /// By default, performs semantic analysis to build the new expression.
-  /// Subclasses may override this routine to provide different behavior.
-  OwningExprResult RebuildQualifiedDeclRefExpr(NestedNameSpecifier *NNS,
-                                               SourceRange QualifierRange,
-                                               NamedDecl *ND,
-                                               SourceLocation Location,
-                                               bool IsAddressOfOperand) {
-    CXXScopeSpec SS;
-    SS.setRange(QualifierRange);
-    SS.setScopeRep(NNS);
-    return getSema().ActOnDeclarationNameExpr(/*Scope=*/0,
-                                              Location,
-                                              ND->getDeclName(),
-                                              /*Trailing lparen=*/false,
-                                              &SS,
-                                              IsAddressOfOperand);
-  }
-
   /// \brief Build a new (previously unresolved) declaration reference
   /// expression.
   ///
@@ -3276,15 +3261,40 @@ TreeTransform<Derived>::TransformPredefinedExpr(PredefinedExpr *E) {
 template<typename Derived>
 Sema::OwningExprResult
 TreeTransform<Derived>::TransformDeclRefExpr(DeclRefExpr *E) {
+  NestedNameSpecifier *Qualifier = 0;
+  if (E->getQualifier()) {
+    Qualifier = getDerived().TransformNestedNameSpecifier(E->getQualifier(),
+                                                       E->getQualifierRange());
+    if (!Qualifier)
+      return SemaRef.ExprError();
+  }
+  
   NamedDecl *ND
     = dyn_cast_or_null<NamedDecl>(getDerived().TransformDecl(E->getDecl()));
   if (!ND)
     return SemaRef.ExprError();
 
-  if (!getDerived().AlwaysRebuild() && ND == E->getDecl())
+  if (!getDerived().AlwaysRebuild() && 
+      Qualifier == E->getQualifier() &&
+      ND == E->getDecl() &&
+      !E->hasExplicitTemplateArgumentList())
     return SemaRef.Owned(E->Retain());
 
-  return getDerived().RebuildDeclRefExpr(ND, E->getLocation());
+  // FIXME: We're losing the explicit template arguments in this transformation.
+
+  llvm::SmallVector<TemplateArgument, 4> TransArgs;
+  for (unsigned I = 0, N = E->getNumTemplateArgs(); I != N; ++I) {
+    TemplateArgument TransArg
+      = getDerived().TransformTemplateArgument(E->getTemplateArgs()[I]);
+    if (TransArg.isNull())
+      return SemaRef.ExprError();
+    
+    TransArgs.push_back(TransArg);
+  }
+  
+  // FIXME: Pass the qualifier/qualifier range along.
+  return getDerived().RebuildDeclRefExpr(Qualifier, E->getQualifierRange(),
+                                         ND, E->getLocation());
 }
 
 template<typename Derived>
@@ -4301,32 +4311,6 @@ TreeTransform<Derived>::TransformUnaryTypeTraitExpr(UnaryTypeTraitExpr *E) {
 
 template<typename Derived>
 Sema::OwningExprResult
-TreeTransform<Derived>::TransformQualifiedDeclRefExpr(QualifiedDeclRefExpr *E) {
-  NestedNameSpecifier *NNS
-    = getDerived().TransformNestedNameSpecifier(E->getQualifier(),
-                                                E->getQualifierRange());
-  if (!NNS)
-    return SemaRef.ExprError();
-
-  NamedDecl *ND
-    = dyn_cast_or_null<NamedDecl>(getDerived().TransformDecl(E->getDecl()));
-  if (!ND)
-    return SemaRef.ExprError();
-
-  if (!getDerived().AlwaysRebuild() &&
-      NNS == E->getQualifier() &&
-      ND == E->getDecl())
-    return SemaRef.Owned(E->Retain());
-
-  return getDerived().RebuildQualifiedDeclRefExpr(NNS,
-                                                  E->getQualifierRange(),
-                                                  ND,
-                                                  E->getLocation(),
-                                                  /*FIXME:*/false);
-}
-
-template<typename Derived>
-Sema::OwningExprResult
 TreeTransform<Derived>::TransformUnresolvedDeclRefExpr(
                                                     UnresolvedDeclRefExpr *E) {
   NestedNameSpecifier *NNS