Revamp our representation of C++ nested-name-specifiers. We now have a
uniqued representation that should both save some memory and make it
far easier to properly build canonical types for types involving
dependent nested-name-specifiers, e.g., "typename T::Nested::type".
This approach will greatly simplify the representation of
CXXScopeSpec. That'll be next.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@67799 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/NestedNameSpecifier.cpp b/lib/AST/NestedNameSpecifier.cpp
index ea4b506..62e972e 100644
--- a/lib/AST/NestedNameSpecifier.cpp
+++ b/lib/AST/NestedNameSpecifier.cpp
@@ -16,46 +16,137 @@
#include "clang/AST/Decl.h"
#include "clang/AST/Type.h"
#include "llvm/Support/raw_ostream.h"
+#include <cassert>
using namespace clang;
-DeclContext *
-NestedNameSpecifier::computeDeclContext(ASTContext &Context) const {
- // The simple case: we're storing a DeclContext
- if ((Data & 0x01) == 0)
- return reinterpret_cast<DeclContext *>(Data);
+NestedNameSpecifier *
+NestedNameSpecifier::FindOrInsert(ASTContext &Context,
+ const NestedNameSpecifier &Mockup) {
+ llvm::FoldingSetNodeID ID;
+ Mockup.Profile(ID);
- Type *T = getAsType();
- if (!T)
- return 0;
+ void *InsertPos = 0;
+ NestedNameSpecifier *NNS
+ = Context.NestedNameSpecifiers.FindNodeOrInsertPos(ID, InsertPos);
+ if (!NNS) {
+ NNS = new (Context) NestedNameSpecifier(Mockup);
+ Context.NestedNameSpecifiers.InsertNode(NNS, InsertPos);
+ }
- // Retrieve the DeclContext associated with this type.
- const TagType *TagT = T->getAsTagType();
- assert(TagT && "No DeclContext from a non-tag type");
- return TagT->getDecl();
+ return NNS;
}
-void NestedNameSpecifier::Print(llvm::raw_ostream &OS,
- const NestedNameSpecifier *First,
- const NestedNameSpecifier *Last) {
- for (; First != Last; ++First) {
- if (Type *T = First->getAsType()) {
- std::string TypeStr;
+NestedNameSpecifier *
+NestedNameSpecifier::Create(ASTContext &Context, NestedNameSpecifier *Prefix,
+ IdentifierInfo *II) {
+ assert(II && "Identifier cannot be NULL");
+ assert(Prefix && Prefix->isDependent() && "Prefix must be dependent");
- // If this is a qualified name type, suppress the qualification:
- // it's part of our nested-name-specifier sequence anyway.
- if (const QualifiedNameType *QualT = dyn_cast<QualifiedNameType>(T))
- T = QualT->getNamedType().getTypePtr();
+ NestedNameSpecifier Mockup;
+ Mockup.Prefix = Prefix;
+ Mockup.Specifier.setPointer(II);
+ Mockup.Specifier.setInt(Identifier);
+ return FindOrInsert(Context, Mockup);
+}
- if (const TagType *TagT = dyn_cast<TagType>(T))
- TagT->getAsStringInternal(TypeStr, true);
- else
- T->getAsStringInternal(TypeStr);
- OS << TypeStr;
- } else if (NamedDecl *NamedDC
- = dyn_cast_or_null<NamedDecl>(First->getAsDeclContext()))
- OS << NamedDC->getNameAsString();
+NestedNameSpecifier *
+NestedNameSpecifier::Create(ASTContext &Context, NestedNameSpecifier *Prefix,
+ NamespaceDecl *NS) {
+ assert(NS && "Namespace cannot be NULL");
+ assert((!Prefix ||
+ (Prefix->getAsType() == 0 && Prefix->getAsIdentifier() == 0)) &&
+ "Broken nested name specifier");
+ NestedNameSpecifier Mockup;
+ Mockup.Prefix = Prefix;
+ Mockup.Specifier.setPointer(NS);
+ Mockup.Specifier.setInt(Namespace);
+ return FindOrInsert(Context, Mockup);
+}
+
+NestedNameSpecifier *
+NestedNameSpecifier::Create(ASTContext &Context, NestedNameSpecifier *Prefix,
+ bool Template, Type *T) {
+ assert(T && "Type cannot be NULL");
+ NestedNameSpecifier Mockup;
+ Mockup.Prefix = Prefix;
+ Mockup.Specifier.setPointer(T);
+ Mockup.Specifier.setInt(Template? TypeSpecWithTemplate : TypeSpec);
+ return FindOrInsert(Context, Mockup);
+}
- OS << "::";
+NestedNameSpecifier *NestedNameSpecifier::GlobalSpecifier(ASTContext &Context) {
+ if (!Context.GlobalNestedNameSpecifier)
+ Context.GlobalNestedNameSpecifier = new (Context) NestedNameSpecifier();
+ return Context.GlobalNestedNameSpecifier;
+}
+
+/// \brief Whether this nested name specifier refers to a dependent
+/// type or not.
+bool NestedNameSpecifier::isDependent() const {
+ switch (getKind()) {
+ case Identifier:
+ // Identifier specifiers always represent dependent types
+ return true;
+
+ case Namespace:
+ case Global:
+ return false;
+
+ case TypeSpec:
+ case TypeSpecWithTemplate:
+ return getAsType()->isDependentType();
}
+
+ // Necessary to suppress a GCC warning.
+ return false;
+}
+
+/// \brief Print this nested name specifier to the given output
+/// stream.
+void NestedNameSpecifier::Print(llvm::raw_ostream &OS) const {
+ if (Prefix)
+ Prefix->Print(OS);
+
+ switch (getKind()) {
+ case Identifier:
+ OS << getAsIdentifier()->getName();
+ break;
+
+ case Namespace:
+ OS << getAsNamespace()->getIdentifier()->getName();
+ break;
+
+ case Global:
+ break;
+
+ case TypeSpecWithTemplate:
+ OS << "template ";
+ // Fall through to print the type.
+
+ case TypeSpec: {
+ std::string TypeStr;
+ Type *T = getAsType();
+
+ // If this is a qualified name type, suppress the qualification:
+ // it's part of our nested-name-specifier sequence anyway. FIXME:
+ // We should be able to assert that this doesn't happen.
+ if (const QualifiedNameType *QualT = dyn_cast<QualifiedNameType>(T))
+ T = QualT->getNamedType().getTypePtr();
+
+ if (const TagType *TagT = dyn_cast<TagType>(T))
+ TagT->getAsStringInternal(TypeStr, true);
+ else
+ T->getAsStringInternal(TypeStr);
+ OS << TypeStr;
+ break;
+ }
+ }
+
+ OS << "::";
+}
+
+void NestedNameSpecifier::Destroy(ASTContext &Context) {
+ this->~NestedNameSpecifier();
+ Context.Deallocate((void *)this);
}