1 //===- NestedNameSpecifier.cpp - C++ nested name specifiers ---------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the NestedNameSpecifier class, which represents
11 // a C++ nested-name-specifier.
13 //===----------------------------------------------------------------------===//
15 #include "clang/AST/NestedNameSpecifier.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/Decl.h"
18 #include "clang/AST/DeclCXX.h"
19 #include "clang/AST/PrettyPrinter.h"
20 #include "clang/AST/TemplateName.h"
21 #include "clang/AST/Type.h"
22 #include "clang/AST/TypeLoc.h"
23 #include "clang/Basic/LLVM.h"
24 #include "clang/Basic/LangOptions.h"
25 #include "clang/Basic/SourceLocation.h"
26 #include "llvm/ADT/FoldingSet.h"
27 #include "llvm/ADT/SmallVector.h"
28 #include "llvm/Support/Casting.h"
29 #include "llvm/Support/Compiler.h"
30 #include "llvm/Support/ErrorHandling.h"
31 #include "llvm/Support/raw_ostream.h"
37 using namespace clang;
40 NestedNameSpecifier::FindOrInsert(const ASTContext &Context,
41 const NestedNameSpecifier &Mockup) {
42 llvm::FoldingSetNodeID ID;
45 void *InsertPos = nullptr;
46 NestedNameSpecifier *NNS
47 = Context.NestedNameSpecifiers.FindNodeOrInsertPos(ID, InsertPos);
50 new (Context, alignof(NestedNameSpecifier)) NestedNameSpecifier(Mockup);
51 Context.NestedNameSpecifiers.InsertNode(NNS, InsertPos);
58 NestedNameSpecifier::Create(const ASTContext &Context,
59 NestedNameSpecifier *Prefix, IdentifierInfo *II) {
60 assert(II && "Identifier cannot be NULL");
61 assert((!Prefix || Prefix->isDependent()) && "Prefix must be dependent");
63 NestedNameSpecifier Mockup;
64 Mockup.Prefix.setPointer(Prefix);
65 Mockup.Prefix.setInt(StoredIdentifier);
66 Mockup.Specifier = II;
67 return FindOrInsert(Context, Mockup);
71 NestedNameSpecifier::Create(const ASTContext &Context,
72 NestedNameSpecifier *Prefix,
73 const NamespaceDecl *NS) {
74 assert(NS && "Namespace cannot be NULL");
76 (Prefix->getAsType() == nullptr &&
77 Prefix->getAsIdentifier() == nullptr)) &&
78 "Broken nested name specifier");
79 NestedNameSpecifier Mockup;
80 Mockup.Prefix.setPointer(Prefix);
81 Mockup.Prefix.setInt(StoredDecl);
82 Mockup.Specifier = const_cast<NamespaceDecl *>(NS);
83 return FindOrInsert(Context, Mockup);
87 NestedNameSpecifier::Create(const ASTContext &Context,
88 NestedNameSpecifier *Prefix,
89 NamespaceAliasDecl *Alias) {
90 assert(Alias && "Namespace alias cannot be NULL");
92 (Prefix->getAsType() == nullptr &&
93 Prefix->getAsIdentifier() == nullptr)) &&
94 "Broken nested name specifier");
95 NestedNameSpecifier Mockup;
96 Mockup.Prefix.setPointer(Prefix);
97 Mockup.Prefix.setInt(StoredDecl);
98 Mockup.Specifier = Alias;
99 return FindOrInsert(Context, Mockup);
102 NestedNameSpecifier *
103 NestedNameSpecifier::Create(const ASTContext &Context,
104 NestedNameSpecifier *Prefix,
105 bool Template, const Type *T) {
106 assert(T && "Type cannot be NULL");
107 NestedNameSpecifier Mockup;
108 Mockup.Prefix.setPointer(Prefix);
109 Mockup.Prefix.setInt(Template? StoredTypeSpecWithTemplate : StoredTypeSpec);
110 Mockup.Specifier = const_cast<Type*>(T);
111 return FindOrInsert(Context, Mockup);
114 NestedNameSpecifier *
115 NestedNameSpecifier::Create(const ASTContext &Context, IdentifierInfo *II) {
116 assert(II && "Identifier cannot be NULL");
117 NestedNameSpecifier Mockup;
118 Mockup.Prefix.setPointer(nullptr);
119 Mockup.Prefix.setInt(StoredIdentifier);
120 Mockup.Specifier = II;
121 return FindOrInsert(Context, Mockup);
124 NestedNameSpecifier *
125 NestedNameSpecifier::GlobalSpecifier(const ASTContext &Context) {
126 if (!Context.GlobalNestedNameSpecifier)
127 Context.GlobalNestedNameSpecifier =
128 new (Context, alignof(NestedNameSpecifier)) NestedNameSpecifier();
129 return Context.GlobalNestedNameSpecifier;
132 NestedNameSpecifier *
133 NestedNameSpecifier::SuperSpecifier(const ASTContext &Context,
135 NestedNameSpecifier Mockup;
136 Mockup.Prefix.setPointer(nullptr);
137 Mockup.Prefix.setInt(StoredDecl);
138 Mockup.Specifier = RD;
139 return FindOrInsert(Context, Mockup);
142 NestedNameSpecifier::SpecifierKind NestedNameSpecifier::getKind() const {
146 switch (Prefix.getInt()) {
147 case StoredIdentifier:
151 NamedDecl *ND = static_cast<NamedDecl *>(Specifier);
152 if (isa<CXXRecordDecl>(ND))
154 return isa<NamespaceDecl>(ND) ? Namespace : NamespaceAlias;
160 case StoredTypeSpecWithTemplate:
161 return TypeSpecWithTemplate;
164 llvm_unreachable("Invalid NNS Kind!");
167 /// \brief Retrieve the namespace stored in this nested name specifier.
168 NamespaceDecl *NestedNameSpecifier::getAsNamespace() const {
169 if (Prefix.getInt() == StoredDecl)
170 return dyn_cast<NamespaceDecl>(static_cast<NamedDecl *>(Specifier));
175 /// \brief Retrieve the namespace alias stored in this nested name specifier.
176 NamespaceAliasDecl *NestedNameSpecifier::getAsNamespaceAlias() const {
177 if (Prefix.getInt() == StoredDecl)
178 return dyn_cast<NamespaceAliasDecl>(static_cast<NamedDecl *>(Specifier));
183 /// \brief Retrieve the record declaration stored in this nested name specifier.
184 CXXRecordDecl *NestedNameSpecifier::getAsRecordDecl() const {
185 switch (Prefix.getInt()) {
186 case StoredIdentifier:
190 return dyn_cast<CXXRecordDecl>(static_cast<NamedDecl *>(Specifier));
193 case StoredTypeSpecWithTemplate:
194 return getAsType()->getAsCXXRecordDecl();
197 llvm_unreachable("Invalid NNS Kind!");
200 /// \brief Whether this nested name specifier refers to a dependent
202 bool NestedNameSpecifier::isDependent() const {
205 // Identifier specifiers always represent dependent types
214 CXXRecordDecl *RD = static_cast<CXXRecordDecl *>(Specifier);
215 for (const auto &Base : RD->bases())
216 if (Base.getType()->isDependentType())
223 case TypeSpecWithTemplate:
224 return getAsType()->isDependentType();
227 llvm_unreachable("Invalid NNS Kind!");
230 /// \brief Whether this nested name specifier refers to a dependent
232 bool NestedNameSpecifier::isInstantiationDependent() const {
235 // Identifier specifiers always represent dependent types
245 case TypeSpecWithTemplate:
246 return getAsType()->isInstantiationDependentType();
249 llvm_unreachable("Invalid NNS Kind!");
252 bool NestedNameSpecifier::containsUnexpandedParameterPack() const {
255 return getPrefix() && getPrefix()->containsUnexpandedParameterPack();
264 case TypeSpecWithTemplate:
265 return getAsType()->containsUnexpandedParameterPack();
268 llvm_unreachable("Invalid NNS Kind!");
271 /// \brief Print this nested name specifier to the given output
274 NestedNameSpecifier::print(raw_ostream &OS,
275 const PrintingPolicy &Policy) const {
277 getPrefix()->print(OS, Policy);
281 OS << getAsIdentifier()->getName();
285 if (getAsNamespace()->isAnonymousNamespace())
288 OS << getAsNamespace()->getName();
292 OS << getAsNamespaceAlias()->getName();
302 case TypeSpecWithTemplate:
304 // Fall through to print the type.
308 const Type *T = getAsType();
310 PrintingPolicy InnerPolicy(Policy);
311 InnerPolicy.SuppressScope = true;
313 // Nested-name-specifiers are intended to contain minimally-qualified
314 // types. An actual ElaboratedType will not occur, since we'll store
315 // just the type that is referred to in the nested-name-specifier (e.g.,
316 // a TypedefType, TagType, etc.). However, when we are dealing with
317 // dependent template-id types (e.g., Outer<T>::template Inner<U>),
318 // the type requires its own nested-name-specifier for uniqueness, so we
319 // suppress that nested-name-specifier during printing.
320 assert(!isa<ElaboratedType>(T) &&
321 "Elaborated type in nested-name-specifier");
322 if (const TemplateSpecializationType *SpecType
323 = dyn_cast<TemplateSpecializationType>(T)) {
324 // Print the template name without its corresponding
325 // nested-name-specifier.
326 SpecType->getTemplateName().print(OS, InnerPolicy, true);
328 // Print the template argument list.
329 printTemplateArgumentList(OS, SpecType->template_arguments(),
332 // Print the type normally
333 QualType(T, 0).print(OS, InnerPolicy);
342 void NestedNameSpecifier::dump(const LangOptions &LO) const {
343 print(llvm::errs(), PrintingPolicy(LO));
346 LLVM_DUMP_METHOD void NestedNameSpecifier::dump() const {
348 print(llvm::errs(), PrintingPolicy(LO));
352 NestedNameSpecifierLoc::getLocalDataLength(NestedNameSpecifier *Qualifier) {
353 assert(Qualifier && "Expected a non-NULL qualifier");
355 // Location of the trailing '::'.
356 unsigned Length = sizeof(unsigned);
358 switch (Qualifier->getKind()) {
359 case NestedNameSpecifier::Global:
360 // Nothing more to add.
363 case NestedNameSpecifier::Identifier:
364 case NestedNameSpecifier::Namespace:
365 case NestedNameSpecifier::NamespaceAlias:
366 case NestedNameSpecifier::Super:
367 // The location of the identifier or namespace name.
368 Length += sizeof(unsigned);
371 case NestedNameSpecifier::TypeSpecWithTemplate:
372 case NestedNameSpecifier::TypeSpec:
373 // The "void*" that points at the TypeLoc data.
374 // Note: the 'template' keyword is part of the TypeLoc.
375 Length += sizeof(void *);
383 NestedNameSpecifierLoc::getDataLength(NestedNameSpecifier *Qualifier) {
385 for (; Qualifier; Qualifier = Qualifier->getPrefix())
386 Length += getLocalDataLength(Qualifier);
390 /// \brief Load a (possibly unaligned) source location from a given address
392 static SourceLocation LoadSourceLocation(void *Data, unsigned Offset) {
394 memcpy(&Raw, static_cast<char *>(Data) + Offset, sizeof(unsigned));
395 return SourceLocation::getFromRawEncoding(Raw);
398 /// \brief Load a (possibly unaligned) pointer from a given address and
400 static void *LoadPointer(void *Data, unsigned Offset) {
402 memcpy(&Result, static_cast<char *>(Data) + Offset, sizeof(void*));
406 SourceRange NestedNameSpecifierLoc::getSourceRange() const {
408 return SourceRange();
410 NestedNameSpecifierLoc First = *this;
411 while (NestedNameSpecifierLoc Prefix = First.getPrefix())
414 return SourceRange(First.getLocalSourceRange().getBegin(),
415 getLocalSourceRange().getEnd());
418 SourceRange NestedNameSpecifierLoc::getLocalSourceRange() const {
420 return SourceRange();
422 unsigned Offset = getDataLength(Qualifier->getPrefix());
423 switch (Qualifier->getKind()) {
424 case NestedNameSpecifier::Global:
425 return LoadSourceLocation(Data, Offset);
427 case NestedNameSpecifier::Identifier:
428 case NestedNameSpecifier::Namespace:
429 case NestedNameSpecifier::NamespaceAlias:
430 case NestedNameSpecifier::Super:
431 return SourceRange(LoadSourceLocation(Data, Offset),
432 LoadSourceLocation(Data, Offset + sizeof(unsigned)));
434 case NestedNameSpecifier::TypeSpecWithTemplate:
435 case NestedNameSpecifier::TypeSpec: {
436 // The "void*" that points at the TypeLoc data.
437 // Note: the 'template' keyword is part of the TypeLoc.
438 void *TypeData = LoadPointer(Data, Offset);
439 TypeLoc TL(Qualifier->getAsType(), TypeData);
440 return SourceRange(TL.getBeginLoc(),
441 LoadSourceLocation(Data, Offset + sizeof(void*)));
445 llvm_unreachable("Invalid NNS Kind!");
448 TypeLoc NestedNameSpecifierLoc::getTypeLoc() const {
449 assert((Qualifier->getKind() == NestedNameSpecifier::TypeSpec ||
450 Qualifier->getKind() == NestedNameSpecifier::TypeSpecWithTemplate) &&
451 "Nested-name-specifier location is not a type");
453 // The "void*" that points at the TypeLoc data.
454 unsigned Offset = getDataLength(Qualifier->getPrefix());
455 void *TypeData = LoadPointer(Data, Offset);
456 return TypeLoc(Qualifier->getAsType(), TypeData);
459 static void Append(char *Start, char *End, char *&Buffer, unsigned &BufferSize,
460 unsigned &BufferCapacity) {
464 if (BufferSize + (End - Start) > BufferCapacity) {
465 // Reallocate the buffer.
466 unsigned NewCapacity = std::max(
467 (unsigned)(BufferCapacity ? BufferCapacity * 2 : sizeof(void *) * 2),
468 (unsigned)(BufferSize + (End - Start)));
469 char *NewBuffer = static_cast<char *>(malloc(NewCapacity));
470 if (BufferCapacity) {
471 memcpy(NewBuffer, Buffer, BufferSize);
475 BufferCapacity = NewCapacity;
478 memcpy(Buffer + BufferSize, Start, End - Start);
479 BufferSize += End-Start;
482 /// \brief Save a source location to the given buffer.
483 static void SaveSourceLocation(SourceLocation Loc, char *&Buffer,
484 unsigned &BufferSize, unsigned &BufferCapacity) {
485 unsigned Raw = Loc.getRawEncoding();
486 Append(reinterpret_cast<char *>(&Raw),
487 reinterpret_cast<char *>(&Raw) + sizeof(unsigned),
488 Buffer, BufferSize, BufferCapacity);
491 /// \brief Save a pointer to the given buffer.
492 static void SavePointer(void *Ptr, char *&Buffer, unsigned &BufferSize,
493 unsigned &BufferCapacity) {
494 Append(reinterpret_cast<char *>(&Ptr),
495 reinterpret_cast<char *>(&Ptr) + sizeof(void *),
496 Buffer, BufferSize, BufferCapacity);
499 NestedNameSpecifierLocBuilder::
500 NestedNameSpecifierLocBuilder(const NestedNameSpecifierLocBuilder &Other)
501 : Representation(Other.Representation) {
505 if (Other.BufferCapacity == 0) {
506 // Shallow copy is okay.
507 Buffer = Other.Buffer;
508 BufferSize = Other.BufferSize;
513 Append(Other.Buffer, Other.Buffer + Other.BufferSize, Buffer, BufferSize,
517 NestedNameSpecifierLocBuilder &
518 NestedNameSpecifierLocBuilder::
519 operator=(const NestedNameSpecifierLocBuilder &Other) {
520 Representation = Other.Representation;
522 if (Buffer && Other.Buffer && BufferCapacity >= Other.BufferSize) {
523 // Re-use our storage.
524 BufferSize = Other.BufferSize;
525 memcpy(Buffer, Other.Buffer, BufferSize);
529 // Free our storage, if we have any.
530 if (BufferCapacity) {
542 if (Other.BufferCapacity == 0) {
543 // Shallow copy is okay.
544 Buffer = Other.Buffer;
545 BufferSize = Other.BufferSize;
550 Append(Other.Buffer, Other.Buffer + Other.BufferSize, Buffer, BufferSize,
555 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
556 SourceLocation TemplateKWLoc,
558 SourceLocation ColonColonLoc) {
559 Representation = NestedNameSpecifier::Create(Context, Representation,
560 TemplateKWLoc.isValid(),
563 // Push source-location info into the buffer.
564 SavePointer(TL.getOpaqueData(), Buffer, BufferSize, BufferCapacity);
565 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
568 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
569 IdentifierInfo *Identifier,
570 SourceLocation IdentifierLoc,
571 SourceLocation ColonColonLoc) {
572 Representation = NestedNameSpecifier::Create(Context, Representation,
575 // Push source-location info into the buffer.
576 SaveSourceLocation(IdentifierLoc, Buffer, BufferSize, BufferCapacity);
577 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
580 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
581 NamespaceDecl *Namespace,
582 SourceLocation NamespaceLoc,
583 SourceLocation ColonColonLoc) {
584 Representation = NestedNameSpecifier::Create(Context, Representation,
587 // Push source-location info into the buffer.
588 SaveSourceLocation(NamespaceLoc, Buffer, BufferSize, BufferCapacity);
589 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
592 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
593 NamespaceAliasDecl *Alias,
594 SourceLocation AliasLoc,
595 SourceLocation ColonColonLoc) {
596 Representation = NestedNameSpecifier::Create(Context, Representation, Alias);
598 // Push source-location info into the buffer.
599 SaveSourceLocation(AliasLoc, Buffer, BufferSize, BufferCapacity);
600 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
603 void NestedNameSpecifierLocBuilder::MakeGlobal(ASTContext &Context,
604 SourceLocation ColonColonLoc) {
605 assert(!Representation && "Already have a nested-name-specifier!?");
606 Representation = NestedNameSpecifier::GlobalSpecifier(Context);
608 // Push source-location info into the buffer.
609 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
612 void NestedNameSpecifierLocBuilder::MakeSuper(ASTContext &Context,
614 SourceLocation SuperLoc,
615 SourceLocation ColonColonLoc) {
616 Representation = NestedNameSpecifier::SuperSpecifier(Context, RD);
618 // Push source-location info into the buffer.
619 SaveSourceLocation(SuperLoc, Buffer, BufferSize, BufferCapacity);
620 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
623 void NestedNameSpecifierLocBuilder::MakeTrivial(ASTContext &Context,
624 NestedNameSpecifier *Qualifier,
626 Representation = Qualifier;
628 // Construct bogus (but well-formed) source information for the
629 // nested-name-specifier.
631 SmallVector<NestedNameSpecifier *, 4> Stack;
632 for (NestedNameSpecifier *NNS = Qualifier; NNS; NNS = NNS->getPrefix())
633 Stack.push_back(NNS);
634 while (!Stack.empty()) {
635 NestedNameSpecifier *NNS = Stack.pop_back_val();
636 switch (NNS->getKind()) {
637 case NestedNameSpecifier::Identifier:
638 case NestedNameSpecifier::Namespace:
639 case NestedNameSpecifier::NamespaceAlias:
640 SaveSourceLocation(R.getBegin(), Buffer, BufferSize, BufferCapacity);
643 case NestedNameSpecifier::TypeSpec:
644 case NestedNameSpecifier::TypeSpecWithTemplate: {
645 TypeSourceInfo *TSInfo
646 = Context.getTrivialTypeSourceInfo(QualType(NNS->getAsType(), 0),
648 SavePointer(TSInfo->getTypeLoc().getOpaqueData(), Buffer, BufferSize,
653 case NestedNameSpecifier::Global:
654 case NestedNameSpecifier::Super:
658 // Save the location of the '::'.
659 SaveSourceLocation(Stack.empty()? R.getEnd() : R.getBegin(),
660 Buffer, BufferSize, BufferCapacity);
664 void NestedNameSpecifierLocBuilder::Adopt(NestedNameSpecifierLoc Other) {
669 Representation = nullptr;
674 // Rather than copying the data (which is wasteful), "adopt" the
675 // pointer (which points into the ASTContext) but set the capacity to zero to
676 // indicate that we don't own it.
677 Representation = Other.getNestedNameSpecifier();
678 Buffer = static_cast<char *>(Other.getOpaqueData());
679 BufferSize = Other.getDataLength();
683 NestedNameSpecifierLoc
684 NestedNameSpecifierLocBuilder::getWithLocInContext(ASTContext &Context) const {
686 return NestedNameSpecifierLoc();
688 // If we adopted our data pointer from elsewhere in the AST context, there's
689 // no need to copy the memory.
690 if (BufferCapacity == 0)
691 return NestedNameSpecifierLoc(Representation, Buffer);
693 // FIXME: After copying the source-location information, should we free
694 // our (temporary) buffer and adopt the ASTContext-allocated memory?
695 // Doing so would optimize repeated calls to getWithLocInContext().
696 void *Mem = Context.Allocate(BufferSize, alignof(void *));
697 memcpy(Mem, Buffer, BufferSize);
698 return NestedNameSpecifierLoc(Representation, Mem);