Implement the semantics of the injected-class-name within a class

template. The injected-class-name is either a type or a template,
depending on whether a '<' follows it. As a type, the
injected-class-name's template argument list contains its template
parameters in declaration order.

As part of this, add logic for canonicalizing declarations, and be
sure to canonicalize declarations used in template names and template
arguments. 

A TagType is dependent if the declaration it references is dependent.

I'm not happy about the rather complicated protocol needed to use
ASTContext::getTemplateSpecializationType.

llvm-svn: 71408

1 files changed, 59 insertions, 0 deletions

diff --git a/clang/lib/AST/DeclTemplate.cpp b/clang/lib/AST/DeclTemplate.cpp
index 7389b83d20d..4f64f8bd508 100644
--- a/clang/lib/AST/DeclTemplate.cpp
+++ b/clang/lib/AST/DeclTemplate.cpp
@@ -120,6 +120,65 @@ void ClassTemplateDecl::Destroy(ASTContext& C) {
   C.Deallocate((void*)this);
 }
 
+QualType ClassTemplateDecl::getInjectedClassNameType(ASTContext &Context) {
+  if (!CommonPtr->InjectedClassNameType.isNull())
+    return CommonPtr->InjectedClassNameType;
+
+  // FIXME: n2800 14.6.1p1 should say how the template arguments
+  // corresponding to template parameter packs should be pack
+  // expansions. We already say that in 14.6.2.1p2, so it would be
+  // better to fix that redundancy.
+
+  TemplateParameterList *Params = getTemplateParameters();
+
+  llvm::SmallVector<TemplateArgument, 16> TemplateArgs;
+  llvm::SmallVector<TemplateArgument, 16> CanonTemplateArgs;
+  TemplateArgs.reserve(Params->size());
+  CanonTemplateArgs.reserve(Params->size());
+
+  for (TemplateParameterList::iterator 
+         Param = Params->begin(), ParamEnd = Params->end(); 
+       Param != ParamEnd; ++Param) {
+    if (isa<TemplateTypeParmDecl>(*Param)) {
+      QualType ParamType = Context.getTypeDeclType(cast<TypeDecl>(*Param));
+      TemplateArgs.push_back(TemplateArgument((*Param)->getLocation(), 
+                                              ParamType));
+      CanonTemplateArgs.push_back(
+                         TemplateArgument((*Param)->getLocation(),
+                                          Context.getCanonicalType(ParamType)));
+    } else if (NonTypeTemplateParmDecl *NTTP = 
+                 dyn_cast<NonTypeTemplateParmDecl>(*Param)) {
+      // FIXME: Build canonical expression, too!
+      Expr *E = new (Context) DeclRefExpr(NTTP, NTTP->getType(),
+                                          NTTP->getLocation(),
+                                          NTTP->getType()->isDependentType(),
+                                          /*Value-dependent=*/true);
+      TemplateArgs.push_back(TemplateArgument(E));
+      CanonTemplateArgs.push_back(TemplateArgument(E));
+    } else { 
+      TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*Param);
+      TemplateArgs.push_back(TemplateArgument(TTP->getLocation(), TTP));
+      CanonTemplateArgs.push_back(TemplateArgument(TTP->getLocation(), 
+                                              Context.getCanonicalDecl(TTP)));
+    }
+  }
+
+  // FIXME: I should really move the "build-the-canonical-type" logic
+  // into ASTContext::getTemplateSpecializationType.
+  TemplateName Name = TemplateName(this);
+  QualType CanonType = Context.getTemplateSpecializationType(
+                                       Context.getCanonicalTemplateName(Name),
+                                             &CanonTemplateArgs[0],
+                                             CanonTemplateArgs.size());
+
+  CommonPtr->InjectedClassNameType
+    = Context.getTemplateSpecializationType(Name,
+                                            &TemplateArgs[0],
+                                            TemplateArgs.size(),
+                                            CanonType);
+  return CommonPtr->InjectedClassNameType;
+}
+
 //===----------------------------------------------------------------------===//
 // TemplateTypeParm Allocation/Deallocation Method Implementations
 //===----------------------------------------------------------------------===//