1 //===- NestedNameSpecifier.cpp - C++ nested name specifiers ---------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file defines the NestedNameSpecifier class, which represents
10 // a C++ nested-name-specifier.
11 //
12 //===----------------------------------------------------------------------===//
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/DeclTemplate.h"
19 #include "clang/AST/DependenceFlags.h"
20 #include "clang/AST/PrettyPrinter.h"
21 #include "clang/AST/TemplateName.h"
22 #include "clang/AST/Type.h"
23 #include "clang/AST/TypeLoc.h"
24 #include "clang/Basic/LLVM.h"
25 #include "clang/Basic/LangOptions.h"
26 #include "clang/Basic/SourceLocation.h"
27 #include "llvm/ADT/FoldingSet.h"
28 #include "llvm/ADT/SmallVector.h"
29 #include "llvm/Support/Casting.h"
30 #include "llvm/Support/Compiler.h"
31 #include "llvm/Support/ErrorHandling.h"
32 #include "llvm/Support/raw_ostream.h"
33 #include <algorithm>
34 #include <cassert>
35 #include <cstdlib>
36 #include <cstring>
37
38 using namespace clang;
39
40 NestedNameSpecifier *
FindOrInsert(const ASTContext & Context,const NestedNameSpecifier & Mockup)41 NestedNameSpecifier::FindOrInsert(const ASTContext &Context,
42 const NestedNameSpecifier &Mockup) {
43 llvm::FoldingSetNodeID ID;
44 Mockup.Profile(ID);
45
46 void *InsertPos = nullptr;
47 NestedNameSpecifier *NNS
48 = Context.NestedNameSpecifiers.FindNodeOrInsertPos(ID, InsertPos);
49 if (!NNS) {
50 NNS =
51 new (Context, alignof(NestedNameSpecifier)) NestedNameSpecifier(Mockup);
52 Context.NestedNameSpecifiers.InsertNode(NNS, InsertPos);
53 }
54
55 return NNS;
56 }
57
Create(const ASTContext & Context,NestedNameSpecifier * Prefix,const IdentifierInfo * II)58 NestedNameSpecifier *NestedNameSpecifier::Create(const ASTContext &Context,
59 NestedNameSpecifier *Prefix,
60 const IdentifierInfo *II) {
61 assert(II && "Identifier cannot be NULL");
62 assert((!Prefix || Prefix->isDependent()) && "Prefix must be dependent");
63
64 NestedNameSpecifier Mockup;
65 Mockup.Prefix.setPointer(Prefix);
66 Mockup.Prefix.setInt(StoredIdentifier);
67 Mockup.Specifier = const_cast<IdentifierInfo *>(II);
68 return FindOrInsert(Context, Mockup);
69 }
70
71 NestedNameSpecifier *
Create(const ASTContext & Context,NestedNameSpecifier * Prefix,const NamespaceDecl * NS)72 NestedNameSpecifier::Create(const ASTContext &Context,
73 NestedNameSpecifier *Prefix,
74 const NamespaceDecl *NS) {
75 assert(NS && "Namespace cannot be NULL");
76 assert((!Prefix ||
77 (Prefix->getAsType() == nullptr &&
78 Prefix->getAsIdentifier() == nullptr)) &&
79 "Broken nested name specifier");
80 NestedNameSpecifier Mockup;
81 Mockup.Prefix.setPointer(Prefix);
82 Mockup.Prefix.setInt(StoredDecl);
83 Mockup.Specifier = const_cast<NamespaceDecl *>(NS);
84 return FindOrInsert(Context, Mockup);
85 }
86
87 NestedNameSpecifier *
Create(const ASTContext & Context,NestedNameSpecifier * Prefix,const NamespaceAliasDecl * Alias)88 NestedNameSpecifier::Create(const ASTContext &Context,
89 NestedNameSpecifier *Prefix,
90 const NamespaceAliasDecl *Alias) {
91 assert(Alias && "Namespace alias cannot be NULL");
92 assert((!Prefix ||
93 (Prefix->getAsType() == nullptr &&
94 Prefix->getAsIdentifier() == nullptr)) &&
95 "Broken nested name specifier");
96 NestedNameSpecifier Mockup;
97 Mockup.Prefix.setPointer(Prefix);
98 Mockup.Prefix.setInt(StoredDecl);
99 Mockup.Specifier = const_cast<NamespaceAliasDecl *>(Alias);
100 return FindOrInsert(Context, Mockup);
101 }
102
103 NestedNameSpecifier *
Create(const ASTContext & Context,NestedNameSpecifier * Prefix,bool Template,const Type * T)104 NestedNameSpecifier::Create(const ASTContext &Context,
105 NestedNameSpecifier *Prefix,
106 bool Template, const Type *T) {
107 assert(T && "Type cannot be NULL");
108 NestedNameSpecifier Mockup;
109 Mockup.Prefix.setPointer(Prefix);
110 Mockup.Prefix.setInt(Template? StoredTypeSpecWithTemplate : StoredTypeSpec);
111 Mockup.Specifier = const_cast<Type*>(T);
112 return FindOrInsert(Context, Mockup);
113 }
114
Create(const ASTContext & Context,const IdentifierInfo * II)115 NestedNameSpecifier *NestedNameSpecifier::Create(const ASTContext &Context,
116 const IdentifierInfo *II) {
117 assert(II && "Identifier cannot be NULL");
118 NestedNameSpecifier Mockup;
119 Mockup.Prefix.setPointer(nullptr);
120 Mockup.Prefix.setInt(StoredIdentifier);
121 Mockup.Specifier = const_cast<IdentifierInfo *>(II);
122 return FindOrInsert(Context, Mockup);
123 }
124
125 NestedNameSpecifier *
GlobalSpecifier(const ASTContext & Context)126 NestedNameSpecifier::GlobalSpecifier(const ASTContext &Context) {
127 if (!Context.GlobalNestedNameSpecifier)
128 Context.GlobalNestedNameSpecifier =
129 new (Context, alignof(NestedNameSpecifier)) NestedNameSpecifier();
130 return Context.GlobalNestedNameSpecifier;
131 }
132
133 NestedNameSpecifier *
SuperSpecifier(const ASTContext & Context,CXXRecordDecl * RD)134 NestedNameSpecifier::SuperSpecifier(const ASTContext &Context,
135 CXXRecordDecl *RD) {
136 NestedNameSpecifier Mockup;
137 Mockup.Prefix.setPointer(nullptr);
138 Mockup.Prefix.setInt(StoredDecl);
139 Mockup.Specifier = RD;
140 return FindOrInsert(Context, Mockup);
141 }
142
getKind() const143 NestedNameSpecifier::SpecifierKind NestedNameSpecifier::getKind() const {
144 if (!Specifier)
145 return Global;
146
147 switch (Prefix.getInt()) {
148 case StoredIdentifier:
149 return Identifier;
150
151 case StoredDecl: {
152 NamedDecl *ND = static_cast<NamedDecl *>(Specifier);
153 if (isa<CXXRecordDecl>(ND))
154 return Super;
155 return isa<NamespaceDecl>(ND) ? Namespace : NamespaceAlias;
156 }
157
158 case StoredTypeSpec:
159 return TypeSpec;
160
161 case StoredTypeSpecWithTemplate:
162 return TypeSpecWithTemplate;
163 }
164
165 llvm_unreachable("Invalid NNS Kind!");
166 }
167
168 /// Retrieve the namespace stored in this nested name specifier.
getAsNamespace() const169 NamespaceDecl *NestedNameSpecifier::getAsNamespace() const {
170 if (Prefix.getInt() == StoredDecl)
171 return dyn_cast<NamespaceDecl>(static_cast<NamedDecl *>(Specifier));
172
173 return nullptr;
174 }
175
176 /// Retrieve the namespace alias stored in this nested name specifier.
getAsNamespaceAlias() const177 NamespaceAliasDecl *NestedNameSpecifier::getAsNamespaceAlias() const {
178 if (Prefix.getInt() == StoredDecl)
179 return dyn_cast<NamespaceAliasDecl>(static_cast<NamedDecl *>(Specifier));
180
181 return nullptr;
182 }
183
184 /// Retrieve the record declaration stored in this nested name specifier.
getAsRecordDecl() const185 CXXRecordDecl *NestedNameSpecifier::getAsRecordDecl() const {
186 switch (Prefix.getInt()) {
187 case StoredIdentifier:
188 return nullptr;
189
190 case StoredDecl:
191 return dyn_cast<CXXRecordDecl>(static_cast<NamedDecl *>(Specifier));
192
193 case StoredTypeSpec:
194 case StoredTypeSpecWithTemplate:
195 return getAsType()->getAsCXXRecordDecl();
196 }
197
198 llvm_unreachable("Invalid NNS Kind!");
199 }
200
getDependence() const201 NestedNameSpecifierDependence NestedNameSpecifier::getDependence() const {
202 switch (getKind()) {
203 case Identifier: {
204 // Identifier specifiers always represent dependent types
205 auto F = NestedNameSpecifierDependence::Dependent |
206 NestedNameSpecifierDependence::Instantiation;
207 // Prefix can contain unexpanded template parameters.
208 if (getPrefix())
209 return F | getPrefix()->getDependence();
210 return F;
211 }
212
213 case Namespace:
214 case NamespaceAlias:
215 case Global:
216 return NestedNameSpecifierDependence::None;
217
218 case Super: {
219 CXXRecordDecl *RD = static_cast<CXXRecordDecl *>(Specifier);
220 for (const auto &Base : RD->bases())
221 if (Base.getType()->isDependentType())
222 // FIXME: must also be instantiation-dependent.
223 return NestedNameSpecifierDependence::Dependent;
224 return NestedNameSpecifierDependence::None;
225 }
226
227 case TypeSpec:
228 case TypeSpecWithTemplate:
229 return toNestedNameSpecifierDependendence(getAsType()->getDependence());
230 }
231 llvm_unreachable("Invalid NNS Kind!");
232 }
233
isDependent() const234 bool NestedNameSpecifier::isDependent() const {
235 return getDependence() & NestedNameSpecifierDependence::Dependent;
236 }
237
isInstantiationDependent() const238 bool NestedNameSpecifier::isInstantiationDependent() const {
239 return getDependence() & NestedNameSpecifierDependence::Instantiation;
240 }
241
containsUnexpandedParameterPack() const242 bool NestedNameSpecifier::containsUnexpandedParameterPack() const {
243 return getDependence() & NestedNameSpecifierDependence::UnexpandedPack;
244 }
245
containsErrors() const246 bool NestedNameSpecifier::containsErrors() const {
247 return getDependence() & NestedNameSpecifierDependence::Error;
248 }
249
250 /// Print this nested name specifier to the given output
251 /// stream.
print(raw_ostream & OS,const PrintingPolicy & Policy,bool ResolveTemplateArguments) const252 void NestedNameSpecifier::print(raw_ostream &OS, const PrintingPolicy &Policy,
253 bool ResolveTemplateArguments) const {
254 if (getPrefix())
255 getPrefix()->print(OS, Policy);
256
257 switch (getKind()) {
258 case Identifier:
259 OS << getAsIdentifier()->getName();
260 break;
261
262 case Namespace:
263 if (getAsNamespace()->isAnonymousNamespace())
264 return;
265
266 OS << getAsNamespace()->getName();
267 break;
268
269 case NamespaceAlias:
270 OS << getAsNamespaceAlias()->getName();
271 break;
272
273 case Global:
274 break;
275
276 case Super:
277 OS << "__super";
278 break;
279
280 case TypeSpecWithTemplate:
281 OS << "template ";
282 // Fall through to print the type.
283 [[fallthrough]];
284
285 case TypeSpec: {
286 const auto *Record =
287 dyn_cast_or_null<ClassTemplateSpecializationDecl>(getAsRecordDecl());
288 if (ResolveTemplateArguments && Record) {
289 // Print the type trait with resolved template parameters.
290 Record->printName(OS, Policy);
291 printTemplateArgumentList(
292 OS, Record->getTemplateArgs().asArray(), Policy,
293 Record->getSpecializedTemplate()->getTemplateParameters());
294 break;
295 }
296 const Type *T = getAsType();
297
298 PrintingPolicy InnerPolicy(Policy);
299 InnerPolicy.SuppressScope = true;
300
301 // Nested-name-specifiers are intended to contain minimally-qualified
302 // types. An actual ElaboratedType will not occur, since we'll store
303 // just the type that is referred to in the nested-name-specifier (e.g.,
304 // a TypedefType, TagType, etc.). However, when we are dealing with
305 // dependent template-id types (e.g., Outer<T>::template Inner<U>),
306 // the type requires its own nested-name-specifier for uniqueness, so we
307 // suppress that nested-name-specifier during printing.
308 assert(!isa<ElaboratedType>(T) &&
309 "Elaborated type in nested-name-specifier");
310 if (const TemplateSpecializationType *SpecType
311 = dyn_cast<TemplateSpecializationType>(T)) {
312 // Print the template name without its corresponding
313 // nested-name-specifier.
314 SpecType->getTemplateName().print(OS, InnerPolicy,
315 TemplateName::Qualified::None);
316
317 // Print the template argument list.
318 printTemplateArgumentList(OS, SpecType->template_arguments(),
319 InnerPolicy);
320 } else if (const auto *DepSpecType =
321 dyn_cast<DependentTemplateSpecializationType>(T)) {
322 // Print the template name without its corresponding
323 // nested-name-specifier.
324 OS << DepSpecType->getIdentifier()->getName();
325 // Print the template argument list.
326 printTemplateArgumentList(OS, DepSpecType->template_arguments(),
327 InnerPolicy);
328 } else {
329 // Print the type normally
330 QualType(T, 0).print(OS, InnerPolicy);
331 }
332 break;
333 }
334 }
335
336 OS << "::";
337 }
338
dump(const LangOptions & LO) const339 LLVM_DUMP_METHOD void NestedNameSpecifier::dump(const LangOptions &LO) const {
340 dump(llvm::errs(), LO);
341 }
342
dump() const343 LLVM_DUMP_METHOD void NestedNameSpecifier::dump() const { dump(llvm::errs()); }
344
dump(llvm::raw_ostream & OS) const345 LLVM_DUMP_METHOD void NestedNameSpecifier::dump(llvm::raw_ostream &OS) const {
346 LangOptions LO;
347 dump(OS, LO);
348 }
349
dump(llvm::raw_ostream & OS,const LangOptions & LO) const350 LLVM_DUMP_METHOD void NestedNameSpecifier::dump(llvm::raw_ostream &OS,
351 const LangOptions &LO) const {
352 print(OS, PrintingPolicy(LO));
353 }
354
355 unsigned
getLocalDataLength(NestedNameSpecifier * Qualifier)356 NestedNameSpecifierLoc::getLocalDataLength(NestedNameSpecifier *Qualifier) {
357 assert(Qualifier && "Expected a non-NULL qualifier");
358
359 // Location of the trailing '::'.
360 unsigned Length = sizeof(SourceLocation::UIntTy);
361
362 switch (Qualifier->getKind()) {
363 case NestedNameSpecifier::Global:
364 // Nothing more to add.
365 break;
366
367 case NestedNameSpecifier::Identifier:
368 case NestedNameSpecifier::Namespace:
369 case NestedNameSpecifier::NamespaceAlias:
370 case NestedNameSpecifier::Super:
371 // The location of the identifier or namespace name.
372 Length += sizeof(SourceLocation::UIntTy);
373 break;
374
375 case NestedNameSpecifier::TypeSpecWithTemplate:
376 case NestedNameSpecifier::TypeSpec:
377 // The "void*" that points at the TypeLoc data.
378 // Note: the 'template' keyword is part of the TypeLoc.
379 Length += sizeof(void *);
380 break;
381 }
382
383 return Length;
384 }
385
386 unsigned
getDataLength(NestedNameSpecifier * Qualifier)387 NestedNameSpecifierLoc::getDataLength(NestedNameSpecifier *Qualifier) {
388 unsigned Length = 0;
389 for (; Qualifier; Qualifier = Qualifier->getPrefix())
390 Length += getLocalDataLength(Qualifier);
391 return Length;
392 }
393
394 /// Load a (possibly unaligned) source location from a given address
395 /// and offset.
LoadSourceLocation(void * Data,unsigned Offset)396 static SourceLocation LoadSourceLocation(void *Data, unsigned Offset) {
397 SourceLocation::UIntTy Raw;
398 memcpy(&Raw, static_cast<char *>(Data) + Offset, sizeof(Raw));
399 return SourceLocation::getFromRawEncoding(Raw);
400 }
401
402 /// Load a (possibly unaligned) pointer from a given address and
403 /// offset.
LoadPointer(void * Data,unsigned Offset)404 static void *LoadPointer(void *Data, unsigned Offset) {
405 void *Result;
406 memcpy(&Result, static_cast<char *>(Data) + Offset, sizeof(void*));
407 return Result;
408 }
409
getSourceRange() const410 SourceRange NestedNameSpecifierLoc::getSourceRange() const {
411 if (!Qualifier)
412 return SourceRange();
413
414 NestedNameSpecifierLoc First = *this;
415 while (NestedNameSpecifierLoc Prefix = First.getPrefix())
416 First = Prefix;
417
418 return SourceRange(First.getLocalSourceRange().getBegin(),
419 getLocalSourceRange().getEnd());
420 }
421
getLocalSourceRange() const422 SourceRange NestedNameSpecifierLoc::getLocalSourceRange() const {
423 if (!Qualifier)
424 return SourceRange();
425
426 unsigned Offset = getDataLength(Qualifier->getPrefix());
427 switch (Qualifier->getKind()) {
428 case NestedNameSpecifier::Global:
429 return LoadSourceLocation(Data, Offset);
430
431 case NestedNameSpecifier::Identifier:
432 case NestedNameSpecifier::Namespace:
433 case NestedNameSpecifier::NamespaceAlias:
434 case NestedNameSpecifier::Super:
435 return SourceRange(
436 LoadSourceLocation(Data, Offset),
437 LoadSourceLocation(Data, Offset + sizeof(SourceLocation::UIntTy)));
438
439 case NestedNameSpecifier::TypeSpecWithTemplate:
440 case NestedNameSpecifier::TypeSpec: {
441 // The "void*" that points at the TypeLoc data.
442 // Note: the 'template' keyword is part of the TypeLoc.
443 void *TypeData = LoadPointer(Data, Offset);
444 TypeLoc TL(Qualifier->getAsType(), TypeData);
445 return SourceRange(TL.getBeginLoc(),
446 LoadSourceLocation(Data, Offset + sizeof(void*)));
447 }
448 }
449
450 llvm_unreachable("Invalid NNS Kind!");
451 }
452
getTypeLoc() const453 TypeLoc NestedNameSpecifierLoc::getTypeLoc() const {
454 if (Qualifier->getKind() != NestedNameSpecifier::TypeSpec &&
455 Qualifier->getKind() != NestedNameSpecifier::TypeSpecWithTemplate)
456 return TypeLoc();
457
458 // The "void*" that points at the TypeLoc data.
459 unsigned Offset = getDataLength(Qualifier->getPrefix());
460 void *TypeData = LoadPointer(Data, Offset);
461 return TypeLoc(Qualifier->getAsType(), TypeData);
462 }
463
Append(char * Start,char * End,char * & Buffer,unsigned & BufferSize,unsigned & BufferCapacity)464 static void Append(char *Start, char *End, char *&Buffer, unsigned &BufferSize,
465 unsigned &BufferCapacity) {
466 if (Start == End)
467 return;
468
469 if (BufferSize + (End - Start) > BufferCapacity) {
470 // Reallocate the buffer.
471 unsigned NewCapacity = std::max(
472 (unsigned)(BufferCapacity ? BufferCapacity * 2 : sizeof(void *) * 2),
473 (unsigned)(BufferSize + (End - Start)));
474 if (!BufferCapacity) {
475 char *NewBuffer = static_cast<char *>(llvm::safe_malloc(NewCapacity));
476 if (Buffer)
477 memcpy(NewBuffer, Buffer, BufferSize);
478 Buffer = NewBuffer;
479 } else {
480 Buffer = static_cast<char *>(llvm::safe_realloc(Buffer, NewCapacity));
481 }
482 BufferCapacity = NewCapacity;
483 }
484 assert(Buffer && Start && End && End > Start && "Illegal memory buffer copy");
485 memcpy(Buffer + BufferSize, Start, End - Start);
486 BufferSize += End - Start;
487 }
488
489 /// Save a source location to the given buffer.
SaveSourceLocation(SourceLocation Loc,char * & Buffer,unsigned & BufferSize,unsigned & BufferCapacity)490 static void SaveSourceLocation(SourceLocation Loc, char *&Buffer,
491 unsigned &BufferSize, unsigned &BufferCapacity) {
492 SourceLocation::UIntTy Raw = Loc.getRawEncoding();
493 Append(reinterpret_cast<char *>(&Raw),
494 reinterpret_cast<char *>(&Raw) + sizeof(Raw), Buffer, BufferSize,
495 BufferCapacity);
496 }
497
498 /// Save a pointer to the given buffer.
SavePointer(void * Ptr,char * & Buffer,unsigned & BufferSize,unsigned & BufferCapacity)499 static void SavePointer(void *Ptr, char *&Buffer, unsigned &BufferSize,
500 unsigned &BufferCapacity) {
501 Append(reinterpret_cast<char *>(&Ptr),
502 reinterpret_cast<char *>(&Ptr) + sizeof(void *),
503 Buffer, BufferSize, BufferCapacity);
504 }
505
506 NestedNameSpecifierLocBuilder::
NestedNameSpecifierLocBuilder(const NestedNameSpecifierLocBuilder & Other)507 NestedNameSpecifierLocBuilder(const NestedNameSpecifierLocBuilder &Other)
508 : Representation(Other.Representation) {
509 if (!Other.Buffer)
510 return;
511
512 if (Other.BufferCapacity == 0) {
513 // Shallow copy is okay.
514 Buffer = Other.Buffer;
515 BufferSize = Other.BufferSize;
516 return;
517 }
518
519 // Deep copy
520 Append(Other.Buffer, Other.Buffer + Other.BufferSize, Buffer, BufferSize,
521 BufferCapacity);
522 }
523
524 NestedNameSpecifierLocBuilder &
525 NestedNameSpecifierLocBuilder::
operator =(const NestedNameSpecifierLocBuilder & Other)526 operator=(const NestedNameSpecifierLocBuilder &Other) {
527 Representation = Other.Representation;
528
529 if (Buffer && Other.Buffer && BufferCapacity >= Other.BufferSize) {
530 // Re-use our storage.
531 BufferSize = Other.BufferSize;
532 memcpy(Buffer, Other.Buffer, BufferSize);
533 return *this;
534 }
535
536 // Free our storage, if we have any.
537 if (BufferCapacity) {
538 free(Buffer);
539 BufferCapacity = 0;
540 }
541
542 if (!Other.Buffer) {
543 // Empty.
544 Buffer = nullptr;
545 BufferSize = 0;
546 return *this;
547 }
548
549 if (Other.BufferCapacity == 0) {
550 // Shallow copy is okay.
551 Buffer = Other.Buffer;
552 BufferSize = Other.BufferSize;
553 return *this;
554 }
555
556 // Deep copy.
557 BufferSize = 0;
558 Append(Other.Buffer, Other.Buffer + Other.BufferSize, Buffer, BufferSize,
559 BufferCapacity);
560 return *this;
561 }
562
Extend(ASTContext & Context,SourceLocation TemplateKWLoc,TypeLoc TL,SourceLocation ColonColonLoc)563 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
564 SourceLocation TemplateKWLoc,
565 TypeLoc TL,
566 SourceLocation ColonColonLoc) {
567 Representation = NestedNameSpecifier::Create(Context, Representation,
568 TemplateKWLoc.isValid(),
569 TL.getTypePtr());
570
571 // Push source-location info into the buffer.
572 SavePointer(TL.getOpaqueData(), Buffer, BufferSize, BufferCapacity);
573 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
574 }
575
Extend(ASTContext & Context,IdentifierInfo * Identifier,SourceLocation IdentifierLoc,SourceLocation ColonColonLoc)576 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
577 IdentifierInfo *Identifier,
578 SourceLocation IdentifierLoc,
579 SourceLocation ColonColonLoc) {
580 Representation = NestedNameSpecifier::Create(Context, Representation,
581 Identifier);
582
583 // Push source-location info into the buffer.
584 SaveSourceLocation(IdentifierLoc, Buffer, BufferSize, BufferCapacity);
585 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
586 }
587
Extend(ASTContext & Context,NamespaceDecl * Namespace,SourceLocation NamespaceLoc,SourceLocation ColonColonLoc)588 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
589 NamespaceDecl *Namespace,
590 SourceLocation NamespaceLoc,
591 SourceLocation ColonColonLoc) {
592 Representation = NestedNameSpecifier::Create(Context, Representation,
593 Namespace);
594
595 // Push source-location info into the buffer.
596 SaveSourceLocation(NamespaceLoc, Buffer, BufferSize, BufferCapacity);
597 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
598 }
599
Extend(ASTContext & Context,NamespaceAliasDecl * Alias,SourceLocation AliasLoc,SourceLocation ColonColonLoc)600 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
601 NamespaceAliasDecl *Alias,
602 SourceLocation AliasLoc,
603 SourceLocation ColonColonLoc) {
604 Representation = NestedNameSpecifier::Create(Context, Representation, Alias);
605
606 // Push source-location info into the buffer.
607 SaveSourceLocation(AliasLoc, Buffer, BufferSize, BufferCapacity);
608 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
609 }
610
MakeGlobal(ASTContext & Context,SourceLocation ColonColonLoc)611 void NestedNameSpecifierLocBuilder::MakeGlobal(ASTContext &Context,
612 SourceLocation ColonColonLoc) {
613 assert(!Representation && "Already have a nested-name-specifier!?");
614 Representation = NestedNameSpecifier::GlobalSpecifier(Context);
615
616 // Push source-location info into the buffer.
617 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
618 }
619
MakeSuper(ASTContext & Context,CXXRecordDecl * RD,SourceLocation SuperLoc,SourceLocation ColonColonLoc)620 void NestedNameSpecifierLocBuilder::MakeSuper(ASTContext &Context,
621 CXXRecordDecl *RD,
622 SourceLocation SuperLoc,
623 SourceLocation ColonColonLoc) {
624 Representation = NestedNameSpecifier::SuperSpecifier(Context, RD);
625
626 // Push source-location info into the buffer.
627 SaveSourceLocation(SuperLoc, Buffer, BufferSize, BufferCapacity);
628 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
629 }
630
MakeTrivial(ASTContext & Context,NestedNameSpecifier * Qualifier,SourceRange R)631 void NestedNameSpecifierLocBuilder::MakeTrivial(ASTContext &Context,
632 NestedNameSpecifier *Qualifier,
633 SourceRange R) {
634 Representation = Qualifier;
635
636 // Construct bogus (but well-formed) source information for the
637 // nested-name-specifier.
638 BufferSize = 0;
639 SmallVector<NestedNameSpecifier *, 4> Stack;
640 for (NestedNameSpecifier *NNS = Qualifier; NNS; NNS = NNS->getPrefix())
641 Stack.push_back(NNS);
642 while (!Stack.empty()) {
643 NestedNameSpecifier *NNS = Stack.pop_back_val();
644 switch (NNS->getKind()) {
645 case NestedNameSpecifier::Identifier:
646 case NestedNameSpecifier::Namespace:
647 case NestedNameSpecifier::NamespaceAlias:
648 SaveSourceLocation(R.getBegin(), Buffer, BufferSize, BufferCapacity);
649 break;
650
651 case NestedNameSpecifier::TypeSpec:
652 case NestedNameSpecifier::TypeSpecWithTemplate: {
653 TypeSourceInfo *TSInfo
654 = Context.getTrivialTypeSourceInfo(QualType(NNS->getAsType(), 0),
655 R.getBegin());
656 SavePointer(TSInfo->getTypeLoc().getOpaqueData(), Buffer, BufferSize,
657 BufferCapacity);
658 break;
659 }
660
661 case NestedNameSpecifier::Global:
662 case NestedNameSpecifier::Super:
663 break;
664 }
665
666 // Save the location of the '::'.
667 SaveSourceLocation(Stack.empty()? R.getEnd() : R.getBegin(),
668 Buffer, BufferSize, BufferCapacity);
669 }
670 }
671
Adopt(NestedNameSpecifierLoc Other)672 void NestedNameSpecifierLocBuilder::Adopt(NestedNameSpecifierLoc Other) {
673 if (BufferCapacity)
674 free(Buffer);
675
676 if (!Other) {
677 Representation = nullptr;
678 BufferSize = 0;
679 return;
680 }
681
682 // Rather than copying the data (which is wasteful), "adopt" the
683 // pointer (which points into the ASTContext) but set the capacity to zero to
684 // indicate that we don't own it.
685 Representation = Other.getNestedNameSpecifier();
686 Buffer = static_cast<char *>(Other.getOpaqueData());
687 BufferSize = Other.getDataLength();
688 BufferCapacity = 0;
689 }
690
691 NestedNameSpecifierLoc
getWithLocInContext(ASTContext & Context) const692 NestedNameSpecifierLocBuilder::getWithLocInContext(ASTContext &Context) const {
693 if (!Representation)
694 return NestedNameSpecifierLoc();
695
696 // If we adopted our data pointer from elsewhere in the AST context, there's
697 // no need to copy the memory.
698 if (BufferCapacity == 0)
699 return NestedNameSpecifierLoc(Representation, Buffer);
700
701 // FIXME: After copying the source-location information, should we free
702 // our (temporary) buffer and adopt the ASTContext-allocated memory?
703 // Doing so would optimize repeated calls to getWithLocInContext().
704 void *Mem = Context.Allocate(BufferSize, alignof(void *));
705 memcpy(Mem, Buffer, BufferSize);
706 return NestedNameSpecifierLoc(Representation, Mem);
707 }
708