1 //===--- NestedNameSpecifier.cpp - C++ nested name specifiers -----*- C++ -*-=//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file defines the NestedNameSpecifier class, which represents
11 // a C++ nested-name-specifier.
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/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"
23 #include <cassert>
24
25 using namespace clang;
26
27 NestedNameSpecifier *
FindOrInsert(const ASTContext & Context,const NestedNameSpecifier & Mockup)28 NestedNameSpecifier::FindOrInsert(const ASTContext &Context,
29 const NestedNameSpecifier &Mockup) {
30 llvm::FoldingSetNodeID ID;
31 Mockup.Profile(ID);
32
33 void *InsertPos = nullptr;
34 NestedNameSpecifier *NNS
35 = Context.NestedNameSpecifiers.FindNodeOrInsertPos(ID, InsertPos);
36 if (!NNS) {
37 NNS = new (Context, llvm::alignOf<NestedNameSpecifier>())
38 NestedNameSpecifier(Mockup);
39 Context.NestedNameSpecifiers.InsertNode(NNS, InsertPos);
40 }
41
42 return NNS;
43 }
44
45 NestedNameSpecifier *
Create(const ASTContext & Context,NestedNameSpecifier * Prefix,IdentifierInfo * II)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");
50
51 NestedNameSpecifier Mockup;
52 Mockup.Prefix.setPointer(Prefix);
53 Mockup.Prefix.setInt(StoredIdentifier);
54 Mockup.Specifier = II;
55 return FindOrInsert(Context, Mockup);
56 }
57
58 NestedNameSpecifier *
Create(const ASTContext & Context,NestedNameSpecifier * Prefix,const NamespaceDecl * NS)59 NestedNameSpecifier::Create(const ASTContext &Context,
60 NestedNameSpecifier *Prefix,
61 const NamespaceDecl *NS) {
62 assert(NS && "Namespace cannot be NULL");
63 assert((!Prefix ||
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);
72 }
73
74 NestedNameSpecifier *
Create(const ASTContext & Context,NestedNameSpecifier * Prefix,NamespaceAliasDecl * Alias)75 NestedNameSpecifier::Create(const ASTContext &Context,
76 NestedNameSpecifier *Prefix,
77 NamespaceAliasDecl *Alias) {
78 assert(Alias && "Namespace alias cannot be NULL");
79 assert((!Prefix ||
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);
88 }
89
90 NestedNameSpecifier *
Create(const ASTContext & Context,NestedNameSpecifier * Prefix,bool Template,const Type * T)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);
100 }
101
102 NestedNameSpecifier *
Create(const ASTContext & Context,IdentifierInfo * II)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);
110 }
111
112 NestedNameSpecifier *
GlobalSpecifier(const ASTContext & Context)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;
119 }
120
121 NestedNameSpecifier *
SuperSpecifier(const ASTContext & Context,CXXRecordDecl * RD)122 NestedNameSpecifier::SuperSpecifier(const ASTContext &Context,
123 CXXRecordDecl *RD) {
124 NestedNameSpecifier Mockup;
125 Mockup.Prefix.setPointer(nullptr);
126 Mockup.Prefix.setInt(StoredDecl);
127 Mockup.Specifier = RD;
128 return FindOrInsert(Context, Mockup);
129 }
130
getKind() const131 NestedNameSpecifier::SpecifierKind NestedNameSpecifier::getKind() const {
132 if (!Specifier)
133 return Global;
134
135 switch (Prefix.getInt()) {
136 case StoredIdentifier:
137 return Identifier;
138
139 case StoredDecl: {
140 NamedDecl *ND = static_cast<NamedDecl *>(Specifier);
141 if (isa<CXXRecordDecl>(ND))
142 return Super;
143 return isa<NamespaceDecl>(ND) ? Namespace : NamespaceAlias;
144 }
145
146 case StoredTypeSpec:
147 return TypeSpec;
148
149 case StoredTypeSpecWithTemplate:
150 return TypeSpecWithTemplate;
151 }
152
153 llvm_unreachable("Invalid NNS Kind!");
154 }
155
156 /// \brief Retrieve the namespace stored in this nested name specifier.
getAsNamespace() const157 NamespaceDecl *NestedNameSpecifier::getAsNamespace() const {
158 if (Prefix.getInt() == StoredDecl)
159 return dyn_cast<NamespaceDecl>(static_cast<NamedDecl *>(Specifier));
160
161 return nullptr;
162 }
163
164 /// \brief Retrieve the namespace alias stored in this nested name specifier.
getAsNamespaceAlias() const165 NamespaceAliasDecl *NestedNameSpecifier::getAsNamespaceAlias() const {
166 if (Prefix.getInt() == StoredDecl)
167 return dyn_cast<NamespaceAliasDecl>(static_cast<NamedDecl *>(Specifier));
168
169 return nullptr;
170 }
171
172 /// \brief Retrieve the record declaration stored in this nested name specifier.
getAsRecordDecl() const173 CXXRecordDecl *NestedNameSpecifier::getAsRecordDecl() const {
174 if (Prefix.getInt() == StoredDecl)
175 return dyn_cast<CXXRecordDecl>(static_cast<NamedDecl *>(Specifier));
176
177 return nullptr;
178 }
179
180 /// \brief Whether this nested name specifier refers to a dependent
181 /// type or not.
isDependent() const182 bool NestedNameSpecifier::isDependent() const {
183 switch (getKind()) {
184 case Identifier:
185 // Identifier specifiers always represent dependent types
186 return true;
187
188 case Namespace:
189 case NamespaceAlias:
190 case Global:
191 return false;
192
193 case Super: {
194 CXXRecordDecl *RD = static_cast<CXXRecordDecl *>(Specifier);
195 for (const auto &Base : RD->bases())
196 if (Base.getType()->isDependentType())
197 return true;
198
199 return false;
200 }
201
202 case TypeSpec:
203 case TypeSpecWithTemplate:
204 return getAsType()->isDependentType();
205 }
206
207 llvm_unreachable("Invalid NNS Kind!");
208 }
209
210 /// \brief Whether this nested name specifier refers to a dependent
211 /// type or not.
isInstantiationDependent() const212 bool NestedNameSpecifier::isInstantiationDependent() const {
213 switch (getKind()) {
214 case Identifier:
215 // Identifier specifiers always represent dependent types
216 return true;
217
218 case Namespace:
219 case NamespaceAlias:
220 case Global:
221 case Super:
222 return false;
223
224 case TypeSpec:
225 case TypeSpecWithTemplate:
226 return getAsType()->isInstantiationDependentType();
227 }
228
229 llvm_unreachable("Invalid NNS Kind!");
230 }
231
containsUnexpandedParameterPack() const232 bool NestedNameSpecifier::containsUnexpandedParameterPack() const {
233 switch (getKind()) {
234 case Identifier:
235 return getPrefix() && getPrefix()->containsUnexpandedParameterPack();
236
237 case Namespace:
238 case NamespaceAlias:
239 case Global:
240 case Super:
241 return false;
242
243 case TypeSpec:
244 case TypeSpecWithTemplate:
245 return getAsType()->containsUnexpandedParameterPack();
246 }
247
248 llvm_unreachable("Invalid NNS Kind!");
249 }
250
251 /// \brief Print this nested name specifier to the given output
252 /// stream.
253 void
print(raw_ostream & OS,const PrintingPolicy & Policy) const254 NestedNameSpecifier::print(raw_ostream &OS,
255 const PrintingPolicy &Policy) const {
256 if (getPrefix())
257 getPrefix()->print(OS, Policy);
258
259 switch (getKind()) {
260 case Identifier:
261 OS << getAsIdentifier()->getName();
262 break;
263
264 case Namespace:
265 if (getAsNamespace()->isAnonymousNamespace())
266 return;
267
268 OS << getAsNamespace()->getName();
269 break;
270
271 case NamespaceAlias:
272 OS << getAsNamespaceAlias()->getName();
273 break;
274
275 case Global:
276 break;
277
278 case Super:
279 OS << "__super";
280 break;
281
282 case TypeSpecWithTemplate:
283 OS << "template ";
284 // Fall through to print the type.
285
286 case TypeSpec: {
287 const Type *T = getAsType();
288
289 PrintingPolicy InnerPolicy(Policy);
290 InnerPolicy.SuppressScope = true;
291
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);
306
307 // Print the template argument list.
308 TemplateSpecializationType::PrintTemplateArgumentList(
309 OS, SpecType->getArgs(), SpecType->getNumArgs(), InnerPolicy);
310 } else {
311 // Print the type normally
312 QualType(T, 0).print(OS, InnerPolicy);
313 }
314 break;
315 }
316 }
317
318 OS << "::";
319 }
320
dump(const LangOptions & LO)321 void NestedNameSpecifier::dump(const LangOptions &LO) {
322 print(llvm::errs(), PrintingPolicy(LO));
323 }
324
325 unsigned
getLocalDataLength(NestedNameSpecifier * Qualifier)326 NestedNameSpecifierLoc::getLocalDataLength(NestedNameSpecifier *Qualifier) {
327 assert(Qualifier && "Expected a non-NULL qualifier");
328
329 // Location of the trailing '::'.
330 unsigned Length = sizeof(unsigned);
331
332 switch (Qualifier->getKind()) {
333 case NestedNameSpecifier::Global:
334 // Nothing more to add.
335 break;
336
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);
343 break;
344
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 *);
350 break;
351 }
352
353 return Length;
354 }
355
356 unsigned
getDataLength(NestedNameSpecifier * Qualifier)357 NestedNameSpecifierLoc::getDataLength(NestedNameSpecifier *Qualifier) {
358 unsigned Length = 0;
359 for (; Qualifier; Qualifier = Qualifier->getPrefix())
360 Length += getLocalDataLength(Qualifier);
361 return Length;
362 }
363
364 namespace {
365 /// \brief Load a (possibly unaligned) source location from a given address
366 /// and offset.
LoadSourceLocation(void * Data,unsigned Offset)367 SourceLocation LoadSourceLocation(void *Data, unsigned Offset) {
368 unsigned Raw;
369 memcpy(&Raw, static_cast<char *>(Data) + Offset, sizeof(unsigned));
370 return SourceLocation::getFromRawEncoding(Raw);
371 }
372
373 /// \brief Load a (possibly unaligned) pointer from a given address and
374 /// offset.
LoadPointer(void * Data,unsigned Offset)375 void *LoadPointer(void *Data, unsigned Offset) {
376 void *Result;
377 memcpy(&Result, static_cast<char *>(Data) + Offset, sizeof(void*));
378 return Result;
379 }
380 }
381
getSourceRange() const382 SourceRange NestedNameSpecifierLoc::getSourceRange() const {
383 if (!Qualifier)
384 return SourceRange();
385
386 NestedNameSpecifierLoc First = *this;
387 while (NestedNameSpecifierLoc Prefix = First.getPrefix())
388 First = Prefix;
389
390 return SourceRange(First.getLocalSourceRange().getBegin(),
391 getLocalSourceRange().getEnd());
392 }
393
getLocalSourceRange() const394 SourceRange NestedNameSpecifierLoc::getLocalSourceRange() const {
395 if (!Qualifier)
396 return SourceRange();
397
398 unsigned Offset = getDataLength(Qualifier->getPrefix());
399 switch (Qualifier->getKind()) {
400 case NestedNameSpecifier::Global:
401 return LoadSourceLocation(Data, Offset);
402
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)));
409
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*)));
418 }
419 }
420
421 llvm_unreachable("Invalid NNS Kind!");
422 }
423
getTypeLoc() const424 TypeLoc NestedNameSpecifierLoc::getTypeLoc() const {
425 assert((Qualifier->getKind() == NestedNameSpecifier::TypeSpec ||
426 Qualifier->getKind() == NestedNameSpecifier::TypeSpecWithTemplate) &&
427 "Nested-name-specifier location is not a type");
428
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);
433 }
434
435 namespace {
Append(char * Start,char * End,char * & Buffer,unsigned & BufferSize,unsigned & BufferCapacity)436 void Append(char *Start, char *End, char *&Buffer, unsigned &BufferSize,
437 unsigned &BufferCapacity) {
438 if (Start == End)
439 return;
440
441 if (BufferSize + (End - Start) > BufferCapacity) {
442 // Reallocate the buffer.
443 unsigned NewCapacity = std::max(
444 (unsigned)(BufferCapacity ? BufferCapacity * 2 : sizeof(void *) * 2),
445 (unsigned)(BufferSize + (End - Start)));
446 char *NewBuffer = static_cast<char *>(malloc(NewCapacity));
447 if (BufferCapacity) {
448 memcpy(NewBuffer, Buffer, BufferSize);
449 free(Buffer);
450 }
451 Buffer = NewBuffer;
452 BufferCapacity = NewCapacity;
453 }
454
455 memcpy(Buffer + BufferSize, Start, End - Start);
456 BufferSize += End-Start;
457 }
458
459 /// \brief Save a source location to the given buffer.
SaveSourceLocation(SourceLocation Loc,char * & Buffer,unsigned & BufferSize,unsigned & BufferCapacity)460 void SaveSourceLocation(SourceLocation Loc, char *&Buffer,
461 unsigned &BufferSize, unsigned &BufferCapacity) {
462 unsigned Raw = Loc.getRawEncoding();
463 Append(reinterpret_cast<char *>(&Raw),
464 reinterpret_cast<char *>(&Raw) + sizeof(unsigned),
465 Buffer, BufferSize, BufferCapacity);
466 }
467
468 /// \brief Save a pointer to the given buffer.
SavePointer(void * Ptr,char * & Buffer,unsigned & BufferSize,unsigned & BufferCapacity)469 void SavePointer(void *Ptr, char *&Buffer, unsigned &BufferSize,
470 unsigned &BufferCapacity) {
471 Append(reinterpret_cast<char *>(&Ptr),
472 reinterpret_cast<char *>(&Ptr) + sizeof(void *),
473 Buffer, BufferSize, BufferCapacity);
474 }
475 }
476
477 NestedNameSpecifierLocBuilder::
NestedNameSpecifierLocBuilder(const NestedNameSpecifierLocBuilder & Other)478 NestedNameSpecifierLocBuilder(const NestedNameSpecifierLocBuilder &Other)
479 : Representation(Other.Representation), Buffer(nullptr),
480 BufferSize(0), BufferCapacity(0)
481 {
482 if (!Other.Buffer)
483 return;
484
485 if (Other.BufferCapacity == 0) {
486 // Shallow copy is okay.
487 Buffer = Other.Buffer;
488 BufferSize = Other.BufferSize;
489 return;
490 }
491
492 // Deep copy
493 Append(Other.Buffer, Other.Buffer + Other.BufferSize, Buffer, BufferSize,
494 BufferCapacity);
495 }
496
497 NestedNameSpecifierLocBuilder &
498 NestedNameSpecifierLocBuilder::
operator =(const NestedNameSpecifierLocBuilder & Other)499 operator=(const NestedNameSpecifierLocBuilder &Other) {
500 Representation = Other.Representation;
501
502 if (Buffer && Other.Buffer && BufferCapacity >= Other.BufferSize) {
503 // Re-use our storage.
504 BufferSize = Other.BufferSize;
505 memcpy(Buffer, Other.Buffer, BufferSize);
506 return *this;
507 }
508
509 // Free our storage, if we have any.
510 if (BufferCapacity) {
511 free(Buffer);
512 BufferCapacity = 0;
513 }
514
515 if (!Other.Buffer) {
516 // Empty.
517 Buffer = nullptr;
518 BufferSize = 0;
519 return *this;
520 }
521
522 if (Other.BufferCapacity == 0) {
523 // Shallow copy is okay.
524 Buffer = Other.Buffer;
525 BufferSize = Other.BufferSize;
526 return *this;
527 }
528
529 // Deep copy.
530 Append(Other.Buffer, Other.Buffer + Other.BufferSize, Buffer, BufferSize,
531 BufferCapacity);
532 return *this;
533 }
534
Extend(ASTContext & Context,SourceLocation TemplateKWLoc,TypeLoc TL,SourceLocation ColonColonLoc)535 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
536 SourceLocation TemplateKWLoc,
537 TypeLoc TL,
538 SourceLocation ColonColonLoc) {
539 Representation = NestedNameSpecifier::Create(Context, Representation,
540 TemplateKWLoc.isValid(),
541 TL.getTypePtr());
542
543 // Push source-location info into the buffer.
544 SavePointer(TL.getOpaqueData(), Buffer, BufferSize, BufferCapacity);
545 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
546 }
547
Extend(ASTContext & Context,IdentifierInfo * Identifier,SourceLocation IdentifierLoc,SourceLocation ColonColonLoc)548 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
549 IdentifierInfo *Identifier,
550 SourceLocation IdentifierLoc,
551 SourceLocation ColonColonLoc) {
552 Representation = NestedNameSpecifier::Create(Context, Representation,
553 Identifier);
554
555 // Push source-location info into the buffer.
556 SaveSourceLocation(IdentifierLoc, Buffer, BufferSize, BufferCapacity);
557 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
558 }
559
Extend(ASTContext & Context,NamespaceDecl * Namespace,SourceLocation NamespaceLoc,SourceLocation ColonColonLoc)560 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
561 NamespaceDecl *Namespace,
562 SourceLocation NamespaceLoc,
563 SourceLocation ColonColonLoc) {
564 Representation = NestedNameSpecifier::Create(Context, Representation,
565 Namespace);
566
567 // Push source-location info into the buffer.
568 SaveSourceLocation(NamespaceLoc, Buffer, BufferSize, BufferCapacity);
569 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
570 }
571
Extend(ASTContext & Context,NamespaceAliasDecl * Alias,SourceLocation AliasLoc,SourceLocation ColonColonLoc)572 void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
573 NamespaceAliasDecl *Alias,
574 SourceLocation AliasLoc,
575 SourceLocation ColonColonLoc) {
576 Representation = NestedNameSpecifier::Create(Context, Representation, Alias);
577
578 // Push source-location info into the buffer.
579 SaveSourceLocation(AliasLoc, Buffer, BufferSize, BufferCapacity);
580 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
581 }
582
MakeGlobal(ASTContext & Context,SourceLocation ColonColonLoc)583 void NestedNameSpecifierLocBuilder::MakeGlobal(ASTContext &Context,
584 SourceLocation ColonColonLoc) {
585 assert(!Representation && "Already have a nested-name-specifier!?");
586 Representation = NestedNameSpecifier::GlobalSpecifier(Context);
587
588 // Push source-location info into the buffer.
589 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
590 }
591
MakeSuper(ASTContext & Context,CXXRecordDecl * RD,SourceLocation SuperLoc,SourceLocation ColonColonLoc)592 void NestedNameSpecifierLocBuilder::MakeSuper(ASTContext &Context,
593 CXXRecordDecl *RD,
594 SourceLocation SuperLoc,
595 SourceLocation ColonColonLoc) {
596 Representation = NestedNameSpecifier::SuperSpecifier(Context, RD);
597
598 // Push source-location info into the buffer.
599 SaveSourceLocation(SuperLoc, Buffer, BufferSize, BufferCapacity);
600 SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
601 }
602
MakeTrivial(ASTContext & Context,NestedNameSpecifier * Qualifier,SourceRange R)603 void NestedNameSpecifierLocBuilder::MakeTrivial(ASTContext &Context,
604 NestedNameSpecifier *Qualifier,
605 SourceRange R) {
606 Representation = Qualifier;
607
608 // Construct bogus (but well-formed) source information for the
609 // nested-name-specifier.
610 BufferSize = 0;
611 SmallVector<NestedNameSpecifier *, 4> Stack;
612 for (NestedNameSpecifier *NNS = Qualifier; NNS; NNS = NNS->getPrefix())
613 Stack.push_back(NNS);
614 while (!Stack.empty()) {
615 NestedNameSpecifier *NNS = Stack.pop_back_val();
616 switch (NNS->getKind()) {
617 case NestedNameSpecifier::Identifier:
618 case NestedNameSpecifier::Namespace:
619 case NestedNameSpecifier::NamespaceAlias:
620 SaveSourceLocation(R.getBegin(), Buffer, BufferSize, BufferCapacity);
621 break;
622
623 case NestedNameSpecifier::TypeSpec:
624 case NestedNameSpecifier::TypeSpecWithTemplate: {
625 TypeSourceInfo *TSInfo
626 = Context.getTrivialTypeSourceInfo(QualType(NNS->getAsType(), 0),
627 R.getBegin());
628 SavePointer(TSInfo->getTypeLoc().getOpaqueData(), Buffer, BufferSize,
629 BufferCapacity);
630 break;
631 }
632
633 case NestedNameSpecifier::Global:
634 case NestedNameSpecifier::Super:
635 break;
636 }
637
638 // Save the location of the '::'.
639 SaveSourceLocation(Stack.empty()? R.getEnd() : R.getBegin(),
640 Buffer, BufferSize, BufferCapacity);
641 }
642 }
643
Adopt(NestedNameSpecifierLoc Other)644 void NestedNameSpecifierLocBuilder::Adopt(NestedNameSpecifierLoc Other) {
645 if (BufferCapacity)
646 free(Buffer);
647
648 if (!Other) {
649 Representation = nullptr;
650 BufferSize = 0;
651 return;
652 }
653
654 // Rather than copying the data (which is wasteful), "adopt" the
655 // pointer (which points into the ASTContext) but set the capacity to zero to
656 // indicate that we don't own it.
657 Representation = Other.getNestedNameSpecifier();
658 Buffer = static_cast<char *>(Other.getOpaqueData());
659 BufferSize = Other.getDataLength();
660 BufferCapacity = 0;
661 }
662
663 NestedNameSpecifierLoc
getWithLocInContext(ASTContext & Context) const664 NestedNameSpecifierLocBuilder::getWithLocInContext(ASTContext &Context) const {
665 if (!Representation)
666 return NestedNameSpecifierLoc();
667
668 // If we adopted our data pointer from elsewhere in the AST context, there's
669 // no need to copy the memory.
670 if (BufferCapacity == 0)
671 return NestedNameSpecifierLoc(Representation, Buffer);
672
673 // FIXME: After copying the source-location information, should we free
674 // our (temporary) buffer and adopt the ASTContext-allocated memory?
675 // Doing so would optimize repeated calls to getWithLocInContext().
676 void *Mem = Context.Allocate(BufferSize, llvm::alignOf<void *>());
677 memcpy(Mem, Buffer, BufferSize);
678 return NestedNameSpecifierLoc(Representation, Mem);
679 }
680