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/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"
32 #include <algorithm>
33 #include <cassert>
34 #include <cstdlib>
35 #include <cstring>
36
37 using namespace clang;
38
39 NestedNameSpecifier *
FindOrInsert(const ASTContext & Context,const NestedNameSpecifier & Mockup)40 NestedNameSpecifier::FindOrInsert(const ASTContext &Context,
41 const NestedNameSpecifier &Mockup) {
42 llvm::FoldingSetNodeID ID;
43 Mockup.Profile(ID);
44
45 void *InsertPos = nullptr;
46 NestedNameSpecifier *NNS
47 = Context.NestedNameSpecifiers.FindNodeOrInsertPos(ID, InsertPos);
48 if (!NNS) {
49 NNS =
50 new (Context, alignof(NestedNameSpecifier)) NestedNameSpecifier(Mockup);
51 Context.NestedNameSpecifiers.InsertNode(NNS, InsertPos);
52 }
53
54 return NNS;
55 }
56
57 NestedNameSpecifier *
Create(const ASTContext & Context,NestedNameSpecifier * Prefix,IdentifierInfo * II)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");
62
63 NestedNameSpecifier Mockup;
64 Mockup.Prefix.setPointer(Prefix);
65 Mockup.Prefix.setInt(StoredIdentifier);
66 Mockup.Specifier = II;
67 return FindOrInsert(Context, Mockup);
68 }
69
70 NestedNameSpecifier *
Create(const ASTContext & Context,NestedNameSpecifier * Prefix,const NamespaceDecl * NS)71 NestedNameSpecifier::Create(const ASTContext &Context,
72 NestedNameSpecifier *Prefix,
73 const NamespaceDecl *NS) {
74 assert(NS && "Namespace cannot be NULL");
75 assert((!Prefix ||
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);
84 }
85
86 NestedNameSpecifier *
Create(const ASTContext & Context,NestedNameSpecifier * Prefix,NamespaceAliasDecl * Alias)87 NestedNameSpecifier::Create(const ASTContext &Context,
88 NestedNameSpecifier *Prefix,
89 NamespaceAliasDecl *Alias) {
90 assert(Alias && "Namespace alias cannot be NULL");
91 assert((!Prefix ||
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);
100 }
101
102 NestedNameSpecifier *
Create(const ASTContext & Context,NestedNameSpecifier * Prefix,bool Template,const Type * T)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);
112 }
113
114 NestedNameSpecifier *
Create(const ASTContext & Context,IdentifierInfo * II)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);
122 }
123
124 NestedNameSpecifier *
GlobalSpecifier(const ASTContext & Context)125 NestedNameSpecifier::GlobalSpecifier(const ASTContext &Context) {
126 if (!Context.GlobalNestedNameSpecifier)
127 Context.GlobalNestedNameSpecifier =
128 new (Context, alignof(NestedNameSpecifier)) NestedNameSpecifier();
129 return Context.GlobalNestedNameSpecifier;
130 }
131
132 NestedNameSpecifier *
SuperSpecifier(const ASTContext & Context,CXXRecordDecl * RD)133 NestedNameSpecifier::SuperSpecifier(const ASTContext &Context,
134 CXXRecordDecl *RD) {
135 NestedNameSpecifier Mockup;
136 Mockup.Prefix.setPointer(nullptr);
137 Mockup.Prefix.setInt(StoredDecl);
138 Mockup.Specifier = RD;
139 return FindOrInsert(Context, Mockup);
140 }
141
getKind() const142 NestedNameSpecifier::SpecifierKind NestedNameSpecifier::getKind() const {
143 if (!Specifier)
144 return Global;
145
146 switch (Prefix.getInt()) {
147 case StoredIdentifier:
148 return Identifier;
149
150 case StoredDecl: {
151 NamedDecl *ND = static_cast<NamedDecl *>(Specifier);
152 if (isa<CXXRecordDecl>(ND))
153 return Super;
154 return isa<NamespaceDecl>(ND) ? Namespace : NamespaceAlias;
155 }
156
157 case StoredTypeSpec:
158 return TypeSpec;
159
160 case StoredTypeSpecWithTemplate:
161 return TypeSpecWithTemplate;
162 }
163
164 llvm_unreachable("Invalid NNS Kind!");
165 }
166
167 /// Retrieve the namespace stored in this nested name specifier.
getAsNamespace() const168 NamespaceDecl *NestedNameSpecifier::getAsNamespace() const {
169 if (Prefix.getInt() == StoredDecl)
170 return dyn_cast<NamespaceDecl>(static_cast<NamedDecl *>(Specifier));
171
172 return nullptr;
173 }
174
175 /// Retrieve the namespace alias stored in this nested name specifier.
getAsNamespaceAlias() const176 NamespaceAliasDecl *NestedNameSpecifier::getAsNamespaceAlias() const {
177 if (Prefix.getInt() == StoredDecl)
178 return dyn_cast<NamespaceAliasDecl>(static_cast<NamedDecl *>(Specifier));
179
180 return nullptr;
181 }
182
183 /// Retrieve the record declaration stored in this nested name specifier.
getAsRecordDecl() const184 CXXRecordDecl *NestedNameSpecifier::getAsRecordDecl() const {
185 switch (Prefix.getInt()) {
186 case StoredIdentifier:
187 return nullptr;
188
189 case StoredDecl:
190 return dyn_cast<CXXRecordDecl>(static_cast<NamedDecl *>(Specifier));
191
192 case StoredTypeSpec:
193 case StoredTypeSpecWithTemplate:
194 return getAsType()->getAsCXXRecordDecl();
195 }
196
197 llvm_unreachable("Invalid NNS Kind!");
198 }
199
200 /// Whether this nested name specifier refers to a dependent
201 /// type or not.
isDependent() const202 bool NestedNameSpecifier::isDependent() const {
203 switch (getKind()) {
204 case Identifier:
205 // Identifier specifiers always represent dependent types
206 return true;
207
208 case Namespace:
209 case NamespaceAlias:
210 case Global:
211 return false;
212
213 case Super: {
214 CXXRecordDecl *RD = static_cast<CXXRecordDecl *>(Specifier);
215 for (const auto &Base : RD->bases())
216 if (Base.getType()->isDependentType())
217 return true;
218
219 return false;
220 }
221
222 case TypeSpec:
223 case TypeSpecWithTemplate:
224 return getAsType()->isDependentType();
225 }
226
227 llvm_unreachable("Invalid NNS Kind!");
228 }
229
230 /// Whether this nested name specifier refers to a dependent
231 /// type or not.
isInstantiationDependent() const232 bool NestedNameSpecifier::isInstantiationDependent() const {
233 switch (getKind()) {
234 case Identifier:
235 // Identifier specifiers always represent dependent types
236 return true;
237
238 case Namespace:
239 case NamespaceAlias:
240 case Global:
241 case Super:
242 return false;
243
244 case TypeSpec:
245 case TypeSpecWithTemplate:
246 return getAsType()->isInstantiationDependentType();
247 }
248
249 llvm_unreachable("Invalid NNS Kind!");
250 }
251
containsUnexpandedParameterPack() const252 bool NestedNameSpecifier::containsUnexpandedParameterPack() const {
253 switch (getKind()) {
254 case Identifier:
255 return getPrefix() && getPrefix()->containsUnexpandedParameterPack();
256
257 case Namespace:
258 case NamespaceAlias:
259 case Global:
260 case Super:
261 return false;
262
263 case TypeSpec:
264 case TypeSpecWithTemplate:
265 return getAsType()->containsUnexpandedParameterPack();
266 }
267
268 llvm_unreachable("Invalid NNS Kind!");
269 }
270
271 /// Print this nested name specifier to the given output
272 /// stream.
print(raw_ostream & OS,const PrintingPolicy & Policy,bool ResolveTemplateArguments) const273 void NestedNameSpecifier::print(raw_ostream &OS, const PrintingPolicy &Policy,
274 bool ResolveTemplateArguments) const {
275 if (getPrefix())
276 getPrefix()->print(OS, Policy);
277
278 switch (getKind()) {
279 case Identifier:
280 OS << getAsIdentifier()->getName();
281 break;
282
283 case Namespace:
284 if (getAsNamespace()->isAnonymousNamespace())
285 return;
286
287 OS << getAsNamespace()->getName();
288 break;
289
290 case NamespaceAlias:
291 OS << getAsNamespaceAlias()->getName();
292 break;
293
294 case Global:
295 break;
296
297 case Super:
298 OS << "__super";
299 break;
300
301 case TypeSpecWithTemplate:
302 OS << "template ";
303 // Fall through to print the type.
304 LLVM_FALLTHROUGH;
305
306 case TypeSpec: {
307 const auto *Record =
308 dyn_cast_or_null<ClassTemplateSpecializationDecl>(getAsRecordDecl());
309 if (ResolveTemplateArguments && Record) {
310 // Print the type trait with resolved template parameters.
311 Record->printName(OS);
312 printTemplateArgumentList(OS, Record->getTemplateArgs().asArray(),
313 Policy);
314 break;
315 }
316 const Type *T = getAsType();
317
318 PrintingPolicy InnerPolicy(Policy);
319 InnerPolicy.SuppressScope = true;
320
321 // Nested-name-specifiers are intended to contain minimally-qualified
322 // types. An actual ElaboratedType will not occur, since we'll store
323 // just the type that is referred to in the nested-name-specifier (e.g.,
324 // a TypedefType, TagType, etc.). However, when we are dealing with
325 // dependent template-id types (e.g., Outer<T>::template Inner<U>),
326 // the type requires its own nested-name-specifier for uniqueness, so we
327 // suppress that nested-name-specifier during printing.
328 assert(!isa<ElaboratedType>(T) &&
329 "Elaborated type in nested-name-specifier");
330 if (const TemplateSpecializationType *SpecType
331 = dyn_cast<TemplateSpecializationType>(T)) {
332 // Print the template name without its corresponding
333 // nested-name-specifier.
334 SpecType->getTemplateName().print(OS, InnerPolicy, true);
335
336 // Print the template argument list.
337 printTemplateArgumentList(OS, SpecType->template_arguments(),
338 InnerPolicy);
339 } else {
340 // Print the type normally
341 QualType(T, 0).print(OS, InnerPolicy);
342 }
343 break;
344 }
345 }
346
347 OS << "::";
348 }
349
dump(const LangOptions & LO) const350 LLVM_DUMP_METHOD void NestedNameSpecifier::dump(const LangOptions &LO) const {
351 dump(llvm::errs(), LO);
352 }
353
dump() const354 LLVM_DUMP_METHOD void NestedNameSpecifier::dump() const { dump(llvm::errs()); }
355
dump(llvm::raw_ostream & OS) const356 LLVM_DUMP_METHOD void NestedNameSpecifier::dump(llvm::raw_ostream &OS) const {
357 LangOptions LO;
358 dump(OS, LO);
359 }
360
dump(llvm::raw_ostream & OS,const LangOptions & LO) const361 LLVM_DUMP_METHOD void NestedNameSpecifier::dump(llvm::raw_ostream &OS,
362 const LangOptions &LO) const {
363 print(OS, PrintingPolicy(LO));
364 }
365
366 unsigned
getLocalDataLength(NestedNameSpecifier * Qualifier)367 NestedNameSpecifierLoc::getLocalDataLength(NestedNameSpecifier *Qualifier) {
368 assert(Qualifier && "Expected a non-NULL qualifier");
369
370 // Location of the trailing '::'.
371 unsigned Length = sizeof(unsigned);
372
373 switch (Qualifier->getKind()) {
374 case NestedNameSpecifier::Global:
375 // Nothing more to add.
376 break;
377
378 case NestedNameSpecifier::Identifier:
379 case NestedNameSpecifier::Namespace:
380 case NestedNameSpecifier::NamespaceAlias:
381 case NestedNameSpecifier::Super:
382 // The location of the identifier or namespace name.
383 Length += sizeof(unsigned);
384 break;
385
386 case NestedNameSpecifier::TypeSpecWithTemplate:
387 case NestedNameSpecifier::TypeSpec:
388 // The "void*" that points at the TypeLoc data.
389 // Note: the 'template' keyword is part of the TypeLoc.
390 Length += sizeof(void *);
391 break;
392 }
393
394 return Length;
395 }
396
397 unsigned
getDataLength(NestedNameSpecifier * Qualifier)398 NestedNameSpecifierLoc::getDataLength(NestedNameSpecifier *Qualifier) {
399 unsigned Length = 0;
400 for (; Qualifier; Qualifier = Qualifier->getPrefix())
401 Length += getLocalDataLength(Qualifier);
402 return Length;
403 }
404
405 /// Load a (possibly unaligned) source location from a given address
406 /// and offset.
LoadSourceLocation(void * Data,unsigned Offset)407 static SourceLocation LoadSourceLocation(void *Data, unsigned Offset) {
408 unsigned Raw;
409 memcpy(&Raw, static_cast<char *>(Data) + Offset, sizeof(unsigned));
410 return SourceLocation::getFromRawEncoding(Raw);
411 }
412
413 /// Load a (possibly unaligned) pointer from a given address and
414 /// offset.
LoadPointer(void * Data,unsigned Offset)415 static void *LoadPointer(void *Data, unsigned Offset) {
416 void *Result;
417 memcpy(&Result, static_cast<char *>(Data) + Offset, sizeof(void*));
418 return Result;
419 }
420
getSourceRange() const421 SourceRange NestedNameSpecifierLoc::getSourceRange() const {
422 if (!Qualifier)
423 return SourceRange();
424
425 NestedNameSpecifierLoc First = *this;
426 while (NestedNameSpecifierLoc Prefix = First.getPrefix())
427 First = Prefix;
428
429 return SourceRange(First.getLocalSourceRange().getBegin(),
430 getLocalSourceRange().getEnd());
431 }
432
getLocalSourceRange() const433 SourceRange NestedNameSpecifierLoc::getLocalSourceRange() const {
434 if (!Qualifier)
435 return SourceRange();
436
437 unsigned Offset = getDataLength(Qualifier->getPrefix());
438 switch (Qualifier->getKind()) {
439 case NestedNameSpecifier::Global:
440 return LoadSourceLocation(Data, Offset);
441
442 case NestedNameSpecifier::Identifier:
443 case NestedNameSpecifier::Namespace:
444 case NestedNameSpecifier::NamespaceAlias:
445 case NestedNameSpecifier::Super:
446 return SourceRange(LoadSourceLocation(Data, Offset),
447 LoadSourceLocation(Data, Offset + sizeof(unsigned)));
448
449 case NestedNameSpecifier::TypeSpecWithTemplate:
450 case NestedNameSpecifier::TypeSpec: {
451 // The "void*" that points at the TypeLoc data.
452 // Note: the 'template' keyword is part of the TypeLoc.
453 void *TypeData = LoadPointer(Data, Offset);
454 TypeLoc TL(Qualifier->getAsType(), TypeData);
455 return SourceRange(TL.getBeginLoc(),
456 LoadSourceLocation(Data, Offset + sizeof(void*)));
457 }
458 }
459
460 llvm_unreachable("Invalid NNS Kind!");
461 }
462
getTypeLoc() const463 TypeLoc NestedNameSpecifierLoc::getTypeLoc() const {
464 if (Qualifier->getKind() != NestedNameSpecifier::TypeSpec &&
465 Qualifier->getKind() != NestedNameSpecifier::TypeSpecWithTemplate)
466 return TypeLoc();
467
468 // The "void*" that points at the TypeLoc data.
469 unsigned Offset = getDataLength(Qualifier->getPrefix());
470 void *TypeData = LoadPointer(Data, Offset);
471 return TypeLoc(Qualifier->getAsType(), TypeData);
472 }
473
Append(char * Start,char * End,char * & Buffer,unsigned & BufferSize,unsigned & BufferCapacity)474 static void Append(char *Start, char *End, char *&Buffer, unsigned &BufferSize,
475 unsigned &BufferCapacity) {
476 if (Start == End)
477 return;
478
479 if (BufferSize + (End - Start) > BufferCapacity) {
480 // Reallocate the buffer.
481 unsigned NewCapacity = std::max(
482 (unsigned)(BufferCapacity ? BufferCapacity * 2 : sizeof(void *) * 2),
483 (unsigned)(BufferSize + (End - Start)));
484 char *NewBuffer = static_cast<char *>(llvm::safe_malloc(NewCapacity));
485 if (BufferCapacity) {
486 memcpy(NewBuffer, Buffer, BufferSize);
487 free(Buffer);
488 }
489 Buffer = NewBuffer;
490 BufferCapacity = NewCapacity;
491 }
492 assert(Buffer && Start && End && End > Start && "Illegal memory buffer copy");
493 memcpy(Buffer + BufferSize, Start, End - Start);
494 BufferSize += End - Start;
495 }
496
497 /// Save a source location to the given buffer.
SaveSourceLocation(SourceLocation Loc,char * & Buffer,unsigned & BufferSize,unsigned & BufferCapacity)498 static void SaveSourceLocation(SourceLocation Loc, char *&Buffer,
499 unsigned &BufferSize, unsigned &BufferCapacity) {
500 unsigned Raw = Loc.getRawEncoding();
501 Append(reinterpret_cast<char *>(&Raw),
502 reinterpret_cast<char *>(&Raw) + sizeof(unsigned),
503 Buffer, BufferSize, BufferCapacity);
504 }
505
506 /// Save a pointer to the given buffer.
SavePointer(void * Ptr,char * & Buffer,unsigned & BufferSize,unsigned & BufferCapacity)507 static void SavePointer(void *Ptr, char *&Buffer, unsigned &BufferSize,
508 unsigned &BufferCapacity) {
509 Append(reinterpret_cast<char *>(&Ptr),
510 reinterpret_cast<char *>(&Ptr) + sizeof(void *),
511 Buffer, BufferSize, BufferCapacity);
512 }
513
514 NestedNameSpecifierLocBuilder::
NestedNameSpecifierLocBuilder(const NestedNameSpecifierLocBuilder & Other)515 NestedNameSpecifierLocBuilder(const NestedNameSpecifierLocBuilder &Other)
516 : Representation(Other.Representation) {
517 if (!Other.Buffer)
518 return;
519
520 if (Other.BufferCapacity == 0) {
521 // Shallow copy is okay.
522 Buffer = Other.Buffer;
523 BufferSize = Other.BufferSize;
524 return;
525 }
526
527 // Deep copy
528 Append(Other.Buffer, Other.Buffer + Other.BufferSize, Buffer, BufferSize,
529 BufferCapacity);
530 }
531
532 NestedNameSpecifierLocBuilder &
533 NestedNameSpecifierLocBuilder::
operator =(const NestedNameSpecifierLocBuilder & Other)534 operator=(const NestedNameSpecifierLocBuilder &Other) {
535 Representation = Other.Representation;
536
537 if (Buffer && Other.Buffer && BufferCapacity >= Other.BufferSize) {
538 // Re-use our storage.
539 BufferSize = Other.BufferSize;
540 memcpy(Buffer, Other.Buffer, BufferSize);
541 return *this;
542 }
543
544 // Free our storage, if we have any.
545 if (BufferCapacity) {
546 free(Buffer);
547 BufferCapacity = 0;
548 }
549
550 if (!Other.Buffer) {
551 // Empty.
552 Buffer = nullptr;
553 BufferSize = 0;
554 return *this;
555 }
556
557 if (Other.BufferCapacity == 0) {
558 // Shallow copy is okay.
559 Buffer = Other.Buffer;
560 BufferSize = Other.BufferSize;
561 return *this;
562 }
563
564 // Deep copy.
565 BufferSize = 0;
566 Append(Other.Buffer, Other.Buffer + Other.BufferSize, Buffer, BufferSize,
567 BufferCapacity);
568 return *this;
569 }
570
Extend(ASTContext & Context,SourceLocation TemplateKWLoc,TypeLoc TL,SourceLocation ColonColonLoc)571 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
572 SourceLocation TemplateKWLoc,
573 TypeLoc TL,
574 SourceLocation ColonColonLoc) {
575 Representation = NestedNameSpecifier::Create(Context, Representation,
576 TemplateKWLoc.isValid(),
577 TL.getTypePtr());
578
579 // Push source-location info into the buffer.
580 SavePointer(TL.getOpaqueData(), Buffer, BufferSize, BufferCapacity);
581 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
582 }
583
Extend(ASTContext & Context,IdentifierInfo * Identifier,SourceLocation IdentifierLoc,SourceLocation ColonColonLoc)584 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
585 IdentifierInfo *Identifier,
586 SourceLocation IdentifierLoc,
587 SourceLocation ColonColonLoc) {
588 Representation = NestedNameSpecifier::Create(Context, Representation,
589 Identifier);
590
591 // Push source-location info into the buffer.
592 SaveSourceLocation(IdentifierLoc, Buffer, BufferSize, BufferCapacity);
593 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
594 }
595
Extend(ASTContext & Context,NamespaceDecl * Namespace,SourceLocation NamespaceLoc,SourceLocation ColonColonLoc)596 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
597 NamespaceDecl *Namespace,
598 SourceLocation NamespaceLoc,
599 SourceLocation ColonColonLoc) {
600 Representation = NestedNameSpecifier::Create(Context, Representation,
601 Namespace);
602
603 // Push source-location info into the buffer.
604 SaveSourceLocation(NamespaceLoc, Buffer, BufferSize, BufferCapacity);
605 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
606 }
607
Extend(ASTContext & Context,NamespaceAliasDecl * Alias,SourceLocation AliasLoc,SourceLocation ColonColonLoc)608 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
609 NamespaceAliasDecl *Alias,
610 SourceLocation AliasLoc,
611 SourceLocation ColonColonLoc) {
612 Representation = NestedNameSpecifier::Create(Context, Representation, Alias);
613
614 // Push source-location info into the buffer.
615 SaveSourceLocation(AliasLoc, Buffer, BufferSize, BufferCapacity);
616 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
617 }
618
MakeGlobal(ASTContext & Context,SourceLocation ColonColonLoc)619 void NestedNameSpecifierLocBuilder::MakeGlobal(ASTContext &Context,
620 SourceLocation ColonColonLoc) {
621 assert(!Representation && "Already have a nested-name-specifier!?");
622 Representation = NestedNameSpecifier::GlobalSpecifier(Context);
623
624 // Push source-location info into the buffer.
625 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
626 }
627
MakeSuper(ASTContext & Context,CXXRecordDecl * RD,SourceLocation SuperLoc,SourceLocation ColonColonLoc)628 void NestedNameSpecifierLocBuilder::MakeSuper(ASTContext &Context,
629 CXXRecordDecl *RD,
630 SourceLocation SuperLoc,
631 SourceLocation ColonColonLoc) {
632 Representation = NestedNameSpecifier::SuperSpecifier(Context, RD);
633
634 // Push source-location info into the buffer.
635 SaveSourceLocation(SuperLoc, Buffer, BufferSize, BufferCapacity);
636 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
637 }
638
MakeTrivial(ASTContext & Context,NestedNameSpecifier * Qualifier,SourceRange R)639 void NestedNameSpecifierLocBuilder::MakeTrivial(ASTContext &Context,
640 NestedNameSpecifier *Qualifier,
641 SourceRange R) {
642 Representation = Qualifier;
643
644 // Construct bogus (but well-formed) source information for the
645 // nested-name-specifier.
646 BufferSize = 0;
647 SmallVector<NestedNameSpecifier *, 4> Stack;
648 for (NestedNameSpecifier *NNS = Qualifier; NNS; NNS = NNS->getPrefix())
649 Stack.push_back(NNS);
650 while (!Stack.empty()) {
651 NestedNameSpecifier *NNS = Stack.pop_back_val();
652 switch (NNS->getKind()) {
653 case NestedNameSpecifier::Identifier:
654 case NestedNameSpecifier::Namespace:
655 case NestedNameSpecifier::NamespaceAlias:
656 SaveSourceLocation(R.getBegin(), Buffer, BufferSize, BufferCapacity);
657 break;
658
659 case NestedNameSpecifier::TypeSpec:
660 case NestedNameSpecifier::TypeSpecWithTemplate: {
661 TypeSourceInfo *TSInfo
662 = Context.getTrivialTypeSourceInfo(QualType(NNS->getAsType(), 0),
663 R.getBegin());
664 SavePointer(TSInfo->getTypeLoc().getOpaqueData(), Buffer, BufferSize,
665 BufferCapacity);
666 break;
667 }
668
669 case NestedNameSpecifier::Global:
670 case NestedNameSpecifier::Super:
671 break;
672 }
673
674 // Save the location of the '::'.
675 SaveSourceLocation(Stack.empty()? R.getEnd() : R.getBegin(),
676 Buffer, BufferSize, BufferCapacity);
677 }
678 }
679
Adopt(NestedNameSpecifierLoc Other)680 void NestedNameSpecifierLocBuilder::Adopt(NestedNameSpecifierLoc Other) {
681 if (BufferCapacity)
682 free(Buffer);
683
684 if (!Other) {
685 Representation = nullptr;
686 BufferSize = 0;
687 return;
688 }
689
690 // Rather than copying the data (which is wasteful), "adopt" the
691 // pointer (which points into the ASTContext) but set the capacity to zero to
692 // indicate that we don't own it.
693 Representation = Other.getNestedNameSpecifier();
694 Buffer = static_cast<char *>(Other.getOpaqueData());
695 BufferSize = Other.getDataLength();
696 BufferCapacity = 0;
697 }
698
699 NestedNameSpecifierLoc
getWithLocInContext(ASTContext & Context) const700 NestedNameSpecifierLocBuilder::getWithLocInContext(ASTContext &Context) const {
701 if (!Representation)
702 return NestedNameSpecifierLoc();
703
704 // If we adopted our data pointer from elsewhere in the AST context, there's
705 // no need to copy the memory.
706 if (BufferCapacity == 0)
707 return NestedNameSpecifierLoc(Representation, Buffer);
708
709 // FIXME: After copying the source-location information, should we free
710 // our (temporary) buffer and adopt the ASTContext-allocated memory?
711 // Doing so would optimize repeated calls to getWithLocInContext().
712 void *Mem = Context.Allocate(BufferSize, alignof(void *));
713 memcpy(Mem, Buffer, BufferSize);
714 return NestedNameSpecifierLoc(Representation, Mem);
715 }
716