1 //===--- NestedNameSpecifier.cpp - C++ nested name specifiers -----*- C++ -*-=//
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 //===----------------------------------------------------------------------===//
14 #include "clang/AST/NestedNameSpecifier.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/Decl.h"
17 #include "clang/AST/DeclCXX.h"
18 #include "clang/AST/PrettyPrinter.h"
19 #include "clang/AST/Type.h"
20 #include "clang/AST/TypeLoc.h"
21 #include "llvm/Support/AlignOf.h"
22 #include "llvm/Support/raw_ostream.h"
25 using namespace clang;
28 NestedNameSpecifier::FindOrInsert(const ASTContext &Context,
29 const NestedNameSpecifier &Mockup) {
30 llvm::FoldingSetNodeID ID;
33 void *InsertPos = nullptr;
34 NestedNameSpecifier *NNS
35 = Context.NestedNameSpecifiers.FindNodeOrInsertPos(ID, InsertPos);
37 NNS = new (Context, llvm::alignOf<NestedNameSpecifier>())
38 NestedNameSpecifier(Mockup);
39 Context.NestedNameSpecifiers.InsertNode(NNS, InsertPos);
46 NestedNameSpecifier::Create(const ASTContext &Context,
47 NestedNameSpecifier *Prefix, IdentifierInfo *II) {
48 assert(II && "Identifier cannot be NULL");
49 assert((!Prefix || Prefix->isDependent()) && "Prefix must be dependent");
51 NestedNameSpecifier Mockup;
52 Mockup.Prefix.setPointer(Prefix);
53 Mockup.Prefix.setInt(StoredIdentifier);
54 Mockup.Specifier = II;
55 return FindOrInsert(Context, Mockup);
59 NestedNameSpecifier::Create(const ASTContext &Context,
60 NestedNameSpecifier *Prefix,
61 const NamespaceDecl *NS) {
62 assert(NS && "Namespace cannot be NULL");
64 (Prefix->getAsType() == nullptr &&
65 Prefix->getAsIdentifier() == nullptr)) &&
66 "Broken nested name specifier");
67 NestedNameSpecifier Mockup;
68 Mockup.Prefix.setPointer(Prefix);
69 Mockup.Prefix.setInt(StoredDecl);
70 Mockup.Specifier = const_cast<NamespaceDecl *>(NS);
71 return FindOrInsert(Context, Mockup);
75 NestedNameSpecifier::Create(const ASTContext &Context,
76 NestedNameSpecifier *Prefix,
77 NamespaceAliasDecl *Alias) {
78 assert(Alias && "Namespace alias cannot be NULL");
80 (Prefix->getAsType() == nullptr &&
81 Prefix->getAsIdentifier() == nullptr)) &&
82 "Broken nested name specifier");
83 NestedNameSpecifier Mockup;
84 Mockup.Prefix.setPointer(Prefix);
85 Mockup.Prefix.setInt(StoredDecl);
86 Mockup.Specifier = Alias;
87 return FindOrInsert(Context, Mockup);
91 NestedNameSpecifier::Create(const ASTContext &Context,
92 NestedNameSpecifier *Prefix,
93 bool Template, const Type *T) {
94 assert(T && "Type cannot be NULL");
95 NestedNameSpecifier Mockup;
96 Mockup.Prefix.setPointer(Prefix);
97 Mockup.Prefix.setInt(Template? StoredTypeSpecWithTemplate : StoredTypeSpec);
98 Mockup.Specifier = const_cast<Type*>(T);
99 return FindOrInsert(Context, Mockup);
102 NestedNameSpecifier *
103 NestedNameSpecifier::Create(const ASTContext &Context, IdentifierInfo *II) {
104 assert(II && "Identifier cannot be NULL");
105 NestedNameSpecifier Mockup;
106 Mockup.Prefix.setPointer(nullptr);
107 Mockup.Prefix.setInt(StoredIdentifier);
108 Mockup.Specifier = II;
109 return FindOrInsert(Context, Mockup);
112 NestedNameSpecifier *
113 NestedNameSpecifier::GlobalSpecifier(const ASTContext &Context) {
114 if (!Context.GlobalNestedNameSpecifier)
115 Context.GlobalNestedNameSpecifier =
116 new (Context, llvm::alignOf<NestedNameSpecifier>())
117 NestedNameSpecifier();
118 return Context.GlobalNestedNameSpecifier;
121 NestedNameSpecifier *
122 NestedNameSpecifier::SuperSpecifier(const ASTContext &Context,
124 NestedNameSpecifier Mockup;
125 Mockup.Prefix.setPointer(nullptr);
126 Mockup.Prefix.setInt(StoredDecl);
127 Mockup.Specifier = RD;
128 return FindOrInsert(Context, Mockup);
131 NestedNameSpecifier::SpecifierKind NestedNameSpecifier::getKind() const {
135 switch (Prefix.getInt()) {
136 case StoredIdentifier:
140 NamedDecl *ND = static_cast<NamedDecl *>(Specifier);
141 if (isa<CXXRecordDecl>(ND))
143 return isa<NamespaceDecl>(ND) ? Namespace : NamespaceAlias;
149 case StoredTypeSpecWithTemplate:
150 return TypeSpecWithTemplate;
153 llvm_unreachable("Invalid NNS Kind!");
156 /// \brief Retrieve the namespace stored in this nested name specifier.
157 NamespaceDecl *NestedNameSpecifier::getAsNamespace() const {
158 if (Prefix.getInt() == StoredDecl)
159 return dyn_cast<NamespaceDecl>(static_cast<NamedDecl *>(Specifier));
164 /// \brief Retrieve the namespace alias stored in this nested name specifier.
165 NamespaceAliasDecl *NestedNameSpecifier::getAsNamespaceAlias() const {
166 if (Prefix.getInt() == StoredDecl)
167 return dyn_cast<NamespaceAliasDecl>(static_cast<NamedDecl *>(Specifier));
172 /// \brief Retrieve the record declaration stored in this nested name specifier.
173 CXXRecordDecl *NestedNameSpecifier::getAsRecordDecl() const {
174 if (Prefix.getInt() == StoredDecl)
175 return dyn_cast<CXXRecordDecl>(static_cast<NamedDecl *>(Specifier));
180 /// \brief Whether this nested name specifier refers to a dependent
182 bool NestedNameSpecifier::isDependent() const {
185 // Identifier specifiers always represent dependent types
194 CXXRecordDecl *RD = static_cast<CXXRecordDecl *>(Specifier);
195 for (const auto &Base : RD->bases())
196 if (Base.getType()->isDependentType())
203 case TypeSpecWithTemplate:
204 return getAsType()->isDependentType();
207 llvm_unreachable("Invalid NNS Kind!");
210 /// \brief Whether this nested name specifier refers to a dependent
212 bool NestedNameSpecifier::isInstantiationDependent() const {
215 // Identifier specifiers always represent dependent types
225 case TypeSpecWithTemplate:
226 return getAsType()->isInstantiationDependentType();
229 llvm_unreachable("Invalid NNS Kind!");
232 bool NestedNameSpecifier::containsUnexpandedParameterPack() const {
235 return getPrefix() && getPrefix()->containsUnexpandedParameterPack();
244 case TypeSpecWithTemplate:
245 return getAsType()->containsUnexpandedParameterPack();
248 llvm_unreachable("Invalid NNS Kind!");
251 /// \brief Print this nested name specifier to the given output
254 NestedNameSpecifier::print(raw_ostream &OS,
255 const PrintingPolicy &Policy) const {
257 getPrefix()->print(OS, Policy);
261 OS << getAsIdentifier()->getName();
265 if (getAsNamespace()->isAnonymousNamespace())
268 OS << getAsNamespace()->getName();
272 OS << getAsNamespaceAlias()->getName();
282 case TypeSpecWithTemplate:
284 // Fall through to print the type.
287 const Type *T = getAsType();
289 PrintingPolicy InnerPolicy(Policy);
290 InnerPolicy.SuppressScope = true;
292 // Nested-name-specifiers are intended to contain minimally-qualified
293 // types. An actual ElaboratedType will not occur, since we'll store
294 // just the type that is referred to in the nested-name-specifier (e.g.,
295 // a TypedefType, TagType, etc.). However, when we are dealing with
296 // dependent template-id types (e.g., Outer<T>::template Inner<U>),
297 // the type requires its own nested-name-specifier for uniqueness, so we
298 // suppress that nested-name-specifier during printing.
299 assert(!isa<ElaboratedType>(T) &&
300 "Elaborated type in nested-name-specifier");
301 if (const TemplateSpecializationType *SpecType
302 = dyn_cast<TemplateSpecializationType>(T)) {
303 // Print the template name without its corresponding
304 // nested-name-specifier.
305 SpecType->getTemplateName().print(OS, InnerPolicy, true);
307 // Print the template argument list.
308 TemplateSpecializationType::PrintTemplateArgumentList(
309 OS, SpecType->getArgs(), SpecType->getNumArgs(), InnerPolicy);
311 // Print the type normally
312 QualType(T, 0).print(OS, InnerPolicy);
321 void NestedNameSpecifier::dump(const LangOptions &LO) {
322 print(llvm::errs(), PrintingPolicy(LO));
326 NestedNameSpecifierLoc::getLocalDataLength(NestedNameSpecifier *Qualifier) {
327 assert(Qualifier && "Expected a non-NULL qualifier");
329 // Location of the trailing '::'.
330 unsigned Length = sizeof(unsigned);
332 switch (Qualifier->getKind()) {
333 case NestedNameSpecifier::Global:
334 // Nothing more to add.
337 case NestedNameSpecifier::Identifier:
338 case NestedNameSpecifier::Namespace:
339 case NestedNameSpecifier::NamespaceAlias:
340 case NestedNameSpecifier::Super:
341 // The location of the identifier or namespace name.
342 Length += sizeof(unsigned);
345 case NestedNameSpecifier::TypeSpecWithTemplate:
346 case NestedNameSpecifier::TypeSpec:
347 // The "void*" that points at the TypeLoc data.
348 // Note: the 'template' keyword is part of the TypeLoc.
349 Length += sizeof(void *);
357 NestedNameSpecifierLoc::getDataLength(NestedNameSpecifier *Qualifier) {
359 for (; Qualifier; Qualifier = Qualifier->getPrefix())
360 Length += getLocalDataLength(Qualifier);
365 /// \brief Load a (possibly unaligned) source location from a given address
367 SourceLocation LoadSourceLocation(void *Data, unsigned Offset) {
369 memcpy(&Raw, static_cast<char *>(Data) + Offset, sizeof(unsigned));
370 return SourceLocation::getFromRawEncoding(Raw);
373 /// \brief Load a (possibly unaligned) pointer from a given address and
375 void *LoadPointer(void *Data, unsigned Offset) {
377 memcpy(&Result, static_cast<char *>(Data) + Offset, sizeof(void*));
382 SourceRange NestedNameSpecifierLoc::getSourceRange() const {
384 return SourceRange();
386 NestedNameSpecifierLoc First = *this;
387 while (NestedNameSpecifierLoc Prefix = First.getPrefix())
390 return SourceRange(First.getLocalSourceRange().getBegin(),
391 getLocalSourceRange().getEnd());
394 SourceRange NestedNameSpecifierLoc::getLocalSourceRange() const {
396 return SourceRange();
398 unsigned Offset = getDataLength(Qualifier->getPrefix());
399 switch (Qualifier->getKind()) {
400 case NestedNameSpecifier::Global:
401 return LoadSourceLocation(Data, Offset);
403 case NestedNameSpecifier::Identifier:
404 case NestedNameSpecifier::Namespace:
405 case NestedNameSpecifier::NamespaceAlias:
406 case NestedNameSpecifier::Super:
407 return SourceRange(LoadSourceLocation(Data, Offset),
408 LoadSourceLocation(Data, Offset + sizeof(unsigned)));
410 case NestedNameSpecifier::TypeSpecWithTemplate:
411 case NestedNameSpecifier::TypeSpec: {
412 // The "void*" that points at the TypeLoc data.
413 // Note: the 'template' keyword is part of the TypeLoc.
414 void *TypeData = LoadPointer(Data, Offset);
415 TypeLoc TL(Qualifier->getAsType(), TypeData);
416 return SourceRange(TL.getBeginLoc(),
417 LoadSourceLocation(Data, Offset + sizeof(void*)));
421 llvm_unreachable("Invalid NNS Kind!");
424 TypeLoc NestedNameSpecifierLoc::getTypeLoc() const {
425 assert((Qualifier->getKind() == NestedNameSpecifier::TypeSpec ||
426 Qualifier->getKind() == NestedNameSpecifier::TypeSpecWithTemplate) &&
427 "Nested-name-specifier location is not a type");
429 // The "void*" that points at the TypeLoc data.
430 unsigned Offset = getDataLength(Qualifier->getPrefix());
431 void *TypeData = LoadPointer(Data, Offset);
432 return TypeLoc(Qualifier->getAsType(), TypeData);
436 void Append(char *Start, char *End, char *&Buffer, unsigned &BufferSize,
437 unsigned &BufferCapacity) {
438 if (BufferSize + (End - Start) > BufferCapacity) {
439 // Reallocate the buffer.
441 = std::max((unsigned)(BufferCapacity? BufferCapacity * 2
442 : sizeof(void*) * 2),
443 (unsigned)(BufferSize + (End - Start)));
444 char *NewBuffer = static_cast<char *>(malloc(NewCapacity));
445 memcpy(NewBuffer, Buffer, BufferSize);
450 BufferCapacity = NewCapacity;
453 memcpy(Buffer + BufferSize, Start, End - Start);
454 BufferSize += End-Start;
457 /// \brief Save a source location to the given buffer.
458 void SaveSourceLocation(SourceLocation Loc, char *&Buffer,
459 unsigned &BufferSize, unsigned &BufferCapacity) {
460 unsigned Raw = Loc.getRawEncoding();
461 Append(reinterpret_cast<char *>(&Raw),
462 reinterpret_cast<char *>(&Raw) + sizeof(unsigned),
463 Buffer, BufferSize, BufferCapacity);
466 /// \brief Save a pointer to the given buffer.
467 void SavePointer(void *Ptr, char *&Buffer, unsigned &BufferSize,
468 unsigned &BufferCapacity) {
469 Append(reinterpret_cast<char *>(&Ptr),
470 reinterpret_cast<char *>(&Ptr) + sizeof(void *),
471 Buffer, BufferSize, BufferCapacity);
475 NestedNameSpecifierLocBuilder::
476 NestedNameSpecifierLocBuilder(const NestedNameSpecifierLocBuilder &Other)
477 : Representation(Other.Representation), Buffer(nullptr),
478 BufferSize(0), BufferCapacity(0)
483 if (Other.BufferCapacity == 0) {
484 // Shallow copy is okay.
485 Buffer = Other.Buffer;
486 BufferSize = Other.BufferSize;
491 Append(Other.Buffer, Other.Buffer + Other.BufferSize, Buffer, BufferSize,
495 NestedNameSpecifierLocBuilder &
496 NestedNameSpecifierLocBuilder::
497 operator=(const NestedNameSpecifierLocBuilder &Other) {
498 Representation = Other.Representation;
500 if (Buffer && Other.Buffer && BufferCapacity >= Other.BufferSize) {
501 // Re-use our storage.
502 BufferSize = Other.BufferSize;
503 memcpy(Buffer, Other.Buffer, BufferSize);
507 // Free our storage, if we have any.
508 if (BufferCapacity) {
520 if (Other.BufferCapacity == 0) {
521 // Shallow copy is okay.
522 Buffer = Other.Buffer;
523 BufferSize = Other.BufferSize;
528 Append(Other.Buffer, Other.Buffer + Other.BufferSize, Buffer, BufferSize,
533 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
534 SourceLocation TemplateKWLoc,
536 SourceLocation ColonColonLoc) {
537 Representation = NestedNameSpecifier::Create(Context, Representation,
538 TemplateKWLoc.isValid(),
541 // Push source-location info into the buffer.
542 SavePointer(TL.getOpaqueData(), Buffer, BufferSize, BufferCapacity);
543 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
546 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
547 IdentifierInfo *Identifier,
548 SourceLocation IdentifierLoc,
549 SourceLocation ColonColonLoc) {
550 Representation = NestedNameSpecifier::Create(Context, Representation,
553 // Push source-location info into the buffer.
554 SaveSourceLocation(IdentifierLoc, Buffer, BufferSize, BufferCapacity);
555 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
558 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
559 NamespaceDecl *Namespace,
560 SourceLocation NamespaceLoc,
561 SourceLocation ColonColonLoc) {
562 Representation = NestedNameSpecifier::Create(Context, Representation,
565 // Push source-location info into the buffer.
566 SaveSourceLocation(NamespaceLoc, Buffer, BufferSize, BufferCapacity);
567 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
570 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
571 NamespaceAliasDecl *Alias,
572 SourceLocation AliasLoc,
573 SourceLocation ColonColonLoc) {
574 Representation = NestedNameSpecifier::Create(Context, Representation, Alias);
576 // Push source-location info into the buffer.
577 SaveSourceLocation(AliasLoc, Buffer, BufferSize, BufferCapacity);
578 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
581 void NestedNameSpecifierLocBuilder::MakeGlobal(ASTContext &Context,
582 SourceLocation ColonColonLoc) {
583 assert(!Representation && "Already have a nested-name-specifier!?");
584 Representation = NestedNameSpecifier::GlobalSpecifier(Context);
586 // Push source-location info into the buffer.
587 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
590 void NestedNameSpecifierLocBuilder::MakeSuper(ASTContext &Context,
592 SourceLocation SuperLoc,
593 SourceLocation ColonColonLoc) {
594 Representation = NestedNameSpecifier::SuperSpecifier(Context, RD);
596 // Push source-location info into the buffer.
597 SaveSourceLocation(SuperLoc, Buffer, BufferSize, BufferCapacity);
598 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
601 void NestedNameSpecifierLocBuilder::MakeTrivial(ASTContext &Context,
602 NestedNameSpecifier *Qualifier,
604 Representation = Qualifier;
606 // Construct bogus (but well-formed) source information for the
607 // nested-name-specifier.
609 SmallVector<NestedNameSpecifier *, 4> Stack;
610 for (NestedNameSpecifier *NNS = Qualifier; NNS; NNS = NNS->getPrefix())
611 Stack.push_back(NNS);
612 while (!Stack.empty()) {
613 NestedNameSpecifier *NNS = Stack.pop_back_val();
614 switch (NNS->getKind()) {
615 case NestedNameSpecifier::Identifier:
616 case NestedNameSpecifier::Namespace:
617 case NestedNameSpecifier::NamespaceAlias:
618 SaveSourceLocation(R.getBegin(), Buffer, BufferSize, BufferCapacity);
621 case NestedNameSpecifier::TypeSpec:
622 case NestedNameSpecifier::TypeSpecWithTemplate: {
623 TypeSourceInfo *TSInfo
624 = Context.getTrivialTypeSourceInfo(QualType(NNS->getAsType(), 0),
626 SavePointer(TSInfo->getTypeLoc().getOpaqueData(), Buffer, BufferSize,
631 case NestedNameSpecifier::Global:
632 case NestedNameSpecifier::Super:
636 // Save the location of the '::'.
637 SaveSourceLocation(Stack.empty()? R.getEnd() : R.getBegin(),
638 Buffer, BufferSize, BufferCapacity);
642 void NestedNameSpecifierLocBuilder::Adopt(NestedNameSpecifierLoc Other) {
647 Representation = nullptr;
652 // Rather than copying the data (which is wasteful), "adopt" the
653 // pointer (which points into the ASTContext) but set the capacity to zero to
654 // indicate that we don't own it.
655 Representation = Other.getNestedNameSpecifier();
656 Buffer = static_cast<char *>(Other.getOpaqueData());
657 BufferSize = Other.getDataLength();
661 NestedNameSpecifierLoc
662 NestedNameSpecifierLocBuilder::getWithLocInContext(ASTContext &Context) const {
664 return NestedNameSpecifierLoc();
666 // If we adopted our data pointer from elsewhere in the AST context, there's
667 // no need to copy the memory.
668 if (BufferCapacity == 0)
669 return NestedNameSpecifierLoc(Representation, Buffer);
671 // FIXME: After copying the source-location information, should we free
672 // our (temporary) buffer and adopt the ASTContext-allocated memory?
673 // Doing so would optimize repeated calls to getWithLocInContext().
674 void *Mem = Context.Allocate(BufferSize, llvm::alignOf<void *>());
675 memcpy(Mem, Buffer, BufferSize);
676 return NestedNameSpecifierLoc(Representation, Mem);