DeclBase.cpp revision e7bae1597f4a7088f5048695c14a8f1013a86108 
1//===--- DeclBase.cpp - Declaration AST Node Implementation ---------------===//
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 implements the Decl and DeclContext classes.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/AST/DeclBase.h"
15#include "clang/AST/ASTContext.h"
16#include "clang/AST/ASTMutationListener.h"
17#include "clang/AST/Attr.h"
18#include "clang/AST/Decl.h"
19#include "clang/AST/DeclCXX.h"
20#include "clang/AST/DeclContextInternals.h"
21#include "clang/AST/DeclFriend.h"
22#include "clang/AST/DeclObjC.h"
23#include "clang/AST/DeclOpenMP.h"
24#include "clang/AST/DeclTemplate.h"
25#include "clang/AST/DependentDiagnostic.h"
26#include "clang/AST/ExternalASTSource.h"
27#include "clang/AST/Stmt.h"
28#include "clang/AST/StmtCXX.h"
29#include "clang/AST/Type.h"
30#include "clang/Basic/TargetInfo.h"
31#include "llvm/ADT/DenseMap.h"
32#include "llvm/Support/raw_ostream.h"
33#include <algorithm>
34using namespace clang;
35
36//===----------------------------------------------------------------------===//
37//  Statistics
38//===----------------------------------------------------------------------===//
39
40#define DECL(DERIVED, BASE) static int n##DERIVED##s = 0;
41#define ABSTRACT_DECL(DECL)
42#include "clang/AST/DeclNodes.inc"
43
44void Decl::updateOutOfDate(IdentifierInfo &II) const {
45  getASTContext().getExternalSource()->updateOutOfDateIdentifier(II);
46}
47
48void *Decl::AllocateDeserializedDecl(const ASTContext &Context,
49                                     unsigned ID,
50                                     unsigned Size) {
51  // Allocate an extra 8 bytes worth of storage, which ensures that the
52  // resulting pointer will still be 8-byte aligned.
53  void *Start = Context.Allocate(Size + 8);
54  void *Result = (char*)Start + 8;
55
56  unsigned *PrefixPtr = (unsigned *)Result - 2;
57
58  // Zero out the first 4 bytes; this is used to store the owning module ID.
59  PrefixPtr[0] = 0;
60
61  // Store the global declaration ID in the second 4 bytes.
62  PrefixPtr[1] = ID;
63
64  return Result;
65}
66
67Module *Decl::getOwningModuleSlow() const {
68  assert(isFromASTFile() && "Not from AST file?");
69  return getASTContext().getExternalSource()->getModule(getOwningModuleID());
70}
71
72const char *Decl::getDeclKindName() const {
73  switch (DeclKind) {
74  default: llvm_unreachable("Declaration not in DeclNodes.inc!");
75#define DECL(DERIVED, BASE) case DERIVED: return #DERIVED;
76#define ABSTRACT_DECL(DECL)
77#include "clang/AST/DeclNodes.inc"
78  }
79}
80
81void Decl::setInvalidDecl(bool Invalid) {
82  InvalidDecl = Invalid;
83  if (Invalid && !isa<ParmVarDecl>(this)) {
84    // Defensive maneuver for ill-formed code: we're likely not to make it to
85    // a point where we set the access specifier, so default it to "public"
86    // to avoid triggering asserts elsewhere in the front end.
87    setAccess(AS_public);
88  }
89}
90
91const char *DeclContext::getDeclKindName() const {
92  switch (DeclKind) {
93  default: llvm_unreachable("Declaration context not in DeclNodes.inc!");
94#define DECL(DERIVED, BASE) case Decl::DERIVED: return #DERIVED;
95#define ABSTRACT_DECL(DECL)
96#include "clang/AST/DeclNodes.inc"
97  }
98}
99
100bool Decl::StatisticsEnabled = false;
101void Decl::EnableStatistics() {
102  StatisticsEnabled = true;
103}
104
105void Decl::PrintStats() {
106  llvm::errs() << "\n*** Decl Stats:\n";
107
108  int totalDecls = 0;
109#define DECL(DERIVED, BASE) totalDecls += n##DERIVED##s;
110#define ABSTRACT_DECL(DECL)
111#include "clang/AST/DeclNodes.inc"
112  llvm::errs() << "  " << totalDecls << " decls total.\n";
113
114  int totalBytes = 0;
115#define DECL(DERIVED, BASE)                                             \
116  if (n##DERIVED##s > 0) {                                              \
117    totalBytes += (int)(n##DERIVED##s * sizeof(DERIVED##Decl));         \
118    llvm::errs() << "    " << n##DERIVED##s << " " #DERIVED " decls, "  \
119                 << sizeof(DERIVED##Decl) << " each ("                  \
120                 << n##DERIVED##s * sizeof(DERIVED##Decl)               \
121                 << " bytes)\n";                                        \
122  }
123#define ABSTRACT_DECL(DECL)
124#include "clang/AST/DeclNodes.inc"
125
126  llvm::errs() << "Total bytes = " << totalBytes << "\n";
127}
128
129void Decl::add(Kind k) {
130  switch (k) {
131#define DECL(DERIVED, BASE) case DERIVED: ++n##DERIVED##s; break;
132#define ABSTRACT_DECL(DECL)
133#include "clang/AST/DeclNodes.inc"
134  }
135}
136
137bool Decl::isTemplateParameterPack() const {
138  if (const TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(this))
139    return TTP->isParameterPack();
140  if (const NonTypeTemplateParmDecl *NTTP
141                                = dyn_cast<NonTypeTemplateParmDecl>(this))
142    return NTTP->isParameterPack();
143  if (const TemplateTemplateParmDecl *TTP
144                                    = dyn_cast<TemplateTemplateParmDecl>(this))
145    return TTP->isParameterPack();
146  return false;
147}
148
149bool Decl::isParameterPack() const {
150  if (const ParmVarDecl *Parm = dyn_cast<ParmVarDecl>(this))
151    return Parm->isParameterPack();
152
153  return isTemplateParameterPack();
154}
155
156bool Decl::isFunctionOrFunctionTemplate() const {
157  if (const UsingShadowDecl *UD = dyn_cast<UsingShadowDecl>(this))
158    return UD->getTargetDecl()->isFunctionOrFunctionTemplate();
159
160  return isa<FunctionDecl>(this) || isa<FunctionTemplateDecl>(this);
161}
162
163bool Decl::isTemplateDecl() const {
164  return isa<TemplateDecl>(this);
165}
166
167const DeclContext *Decl::getParentFunctionOrMethod() const {
168  for (const DeclContext *DC = getDeclContext();
169       DC && !DC->isTranslationUnit() && !DC->isNamespace();
170       DC = DC->getParent())
171    if (DC->isFunctionOrMethod())
172      return DC;
173
174  return 0;
175}
176
177
178//===----------------------------------------------------------------------===//
179// PrettyStackTraceDecl Implementation
180//===----------------------------------------------------------------------===//
181
182void PrettyStackTraceDecl::print(raw_ostream &OS) const {
183  SourceLocation TheLoc = Loc;
184  if (TheLoc.isInvalid() && TheDecl)
185    TheLoc = TheDecl->getLocation();
186
187  if (TheLoc.isValid()) {
188    TheLoc.print(OS, SM);
189    OS << ": ";
190  }
191
192  OS << Message;
193
194  if (const NamedDecl *DN = dyn_cast_or_null<NamedDecl>(TheDecl)) {
195    OS << " '";
196    DN->printQualifiedName(OS);
197    OS << '\'';
198  }
199  OS << '\n';
200}
201
202//===----------------------------------------------------------------------===//
203// Decl Implementation
204//===----------------------------------------------------------------------===//
205
206// Out-of-line virtual method providing a home for Decl.
207Decl::~Decl() { }
208
209void Decl::setDeclContext(DeclContext *DC) {
210  DeclCtx = DC;
211}
212
213void Decl::setLexicalDeclContext(DeclContext *DC) {
214  if (DC == getLexicalDeclContext())
215    return;
216
217  if (isInSemaDC()) {
218    setDeclContextsImpl(getDeclContext(), DC, getASTContext());
219  } else {
220    getMultipleDC()->LexicalDC = DC;
221  }
222}
223
224void Decl::setDeclContextsImpl(DeclContext *SemaDC, DeclContext *LexicalDC,
225                               ASTContext &Ctx) {
226  if (SemaDC == LexicalDC) {
227    DeclCtx = SemaDC;
228  } else {
229    Decl::MultipleDC *MDC = new (Ctx) Decl::MultipleDC();
230    MDC->SemanticDC = SemaDC;
231    MDC->LexicalDC = LexicalDC;
232    DeclCtx = MDC;
233  }
234}
235
236bool Decl::isInAnonymousNamespace() const {
237  const DeclContext *DC = getDeclContext();
238  do {
239    if (const NamespaceDecl *ND = dyn_cast<NamespaceDecl>(DC))
240      if (ND->isAnonymousNamespace())
241        return true;
242  } while ((DC = DC->getParent()));
243
244  return false;
245}
246
247TranslationUnitDecl *Decl::getTranslationUnitDecl() {
248  if (TranslationUnitDecl *TUD = dyn_cast<TranslationUnitDecl>(this))
249    return TUD;
250
251  DeclContext *DC = getDeclContext();
252  assert(DC && "This decl is not contained in a translation unit!");
253
254  while (!DC->isTranslationUnit()) {
255    DC = DC->getParent();
256    assert(DC && "This decl is not contained in a translation unit!");
257  }
258
259  return cast<TranslationUnitDecl>(DC);
260}
261
262ASTContext &Decl::getASTContext() const {
263  return getTranslationUnitDecl()->getASTContext();
264}
265
266ASTMutationListener *Decl::getASTMutationListener() const {
267  return getASTContext().getASTMutationListener();
268}
269
270unsigned Decl::getMaxAlignment() const {
271  if (!hasAttrs())
272    return 0;
273
274  unsigned Align = 0;
275  const AttrVec &V = getAttrs();
276  ASTContext &Ctx = getASTContext();
277  specific_attr_iterator<AlignedAttr> I(V.begin()), E(V.end());
278  for (; I != E; ++I)
279    Align = std::max(Align, I->getAlignment(Ctx));
280  return Align;
281}
282
283bool Decl::isUsed(bool CheckUsedAttr) const {
284  if (Used)
285    return true;
286
287  // Check for used attribute.
288  if (CheckUsedAttr && hasAttr<UsedAttr>())
289    return true;
290
291  return false;
292}
293
294bool Decl::isReferenced() const {
295  if (Referenced)
296    return true;
297
298  // Check redeclarations.
299  for (redecl_iterator I = redecls_begin(), E = redecls_end(); I != E; ++I)
300    if (I->Referenced)
301      return true;
302
303  return false;
304}
305
306/// \brief Determine the availability of the given declaration based on
307/// the target platform.
308///
309/// When it returns an availability result other than \c AR_Available,
310/// if the \p Message parameter is non-NULL, it will be set to a
311/// string describing why the entity is unavailable.
312///
313/// FIXME: Make these strings localizable, since they end up in
314/// diagnostics.
315static AvailabilityResult CheckAvailability(ASTContext &Context,
316                                            const AvailabilityAttr *A,
317                                            std::string *Message) {
318  StringRef TargetPlatform = Context.getTargetInfo().getPlatformName();
319  StringRef PrettyPlatformName
320    = AvailabilityAttr::getPrettyPlatformName(TargetPlatform);
321  if (PrettyPlatformName.empty())
322    PrettyPlatformName = TargetPlatform;
323
324  VersionTuple TargetMinVersion = Context.getTargetInfo().getPlatformMinVersion();
325  if (TargetMinVersion.empty())
326    return AR_Available;
327
328  // Match the platform name.
329  if (A->getPlatform()->getName() != TargetPlatform)
330    return AR_Available;
331
332  std::string HintMessage;
333  if (!A->getMessage().empty()) {
334    HintMessage = " - ";
335    HintMessage += A->getMessage();
336  }
337
338  // Make sure that this declaration has not been marked 'unavailable'.
339  if (A->getUnavailable()) {
340    if (Message) {
341      Message->clear();
342      llvm::raw_string_ostream Out(*Message);
343      Out << "not available on " << PrettyPlatformName
344          << HintMessage;
345    }
346
347    return AR_Unavailable;
348  }
349
350  // Make sure that this declaration has already been introduced.
351  if (!A->getIntroduced().empty() &&
352      TargetMinVersion < A->getIntroduced()) {
353    if (Message) {
354      Message->clear();
355      llvm::raw_string_ostream Out(*Message);
356      Out << "introduced in " << PrettyPlatformName << ' '
357          << A->getIntroduced() << HintMessage;
358    }
359
360    return AR_NotYetIntroduced;
361  }
362
363  // Make sure that this declaration hasn't been obsoleted.
364  if (!A->getObsoleted().empty() && TargetMinVersion >= A->getObsoleted()) {
365    if (Message) {
366      Message->clear();
367      llvm::raw_string_ostream Out(*Message);
368      Out << "obsoleted in " << PrettyPlatformName << ' '
369          << A->getObsoleted() << HintMessage;
370    }
371
372    return AR_Unavailable;
373  }
374
375  // Make sure that this declaration hasn't been deprecated.
376  if (!A->getDeprecated().empty() && TargetMinVersion >= A->getDeprecated()) {
377    if (Message) {
378      Message->clear();
379      llvm::raw_string_ostream Out(*Message);
380      Out << "first deprecated in " << PrettyPlatformName << ' '
381          << A->getDeprecated() << HintMessage;
382    }
383
384    return AR_Deprecated;
385  }
386
387  return AR_Available;
388}
389
390AvailabilityResult Decl::getAvailability(std::string *Message) const {
391  AvailabilityResult Result = AR_Available;
392  std::string ResultMessage;
393
394  for (attr_iterator A = attr_begin(), AEnd = attr_end(); A != AEnd; ++A) {
395    if (DeprecatedAttr *Deprecated = dyn_cast<DeprecatedAttr>(*A)) {
396      if (Result >= AR_Deprecated)
397        continue;
398
399      if (Message)
400        ResultMessage = Deprecated->getMessage();
401
402      Result = AR_Deprecated;
403      continue;
404    }
405
406    if (UnavailableAttr *Unavailable = dyn_cast<UnavailableAttr>(*A)) {
407      if (Message)
408        *Message = Unavailable->getMessage();
409      return AR_Unavailable;
410    }
411
412    if (AvailabilityAttr *Availability = dyn_cast<AvailabilityAttr>(*A)) {
413      AvailabilityResult AR = CheckAvailability(getASTContext(), Availability,
414                                                Message);
415
416      if (AR == AR_Unavailable)
417        return AR_Unavailable;
418
419      if (AR > Result) {
420        Result = AR;
421        if (Message)
422          ResultMessage.swap(*Message);
423      }
424      continue;
425    }
426  }
427
428  if (Message)
429    Message->swap(ResultMessage);
430  return Result;
431}
432
433bool Decl::canBeWeakImported(bool &IsDefinition) const {
434  IsDefinition = false;
435
436  // Variables, if they aren't definitions.
437  if (const VarDecl *Var = dyn_cast<VarDecl>(this)) {
438    if (Var->isThisDeclarationADefinition()) {
439      IsDefinition = true;
440      return false;
441    }
442    return true;
443
444  // Functions, if they aren't definitions.
445  } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(this)) {
446    if (FD->hasBody()) {
447      IsDefinition = true;
448      return false;
449    }
450    return true;
451
452  // Objective-C classes, if this is the non-fragile runtime.
453  } else if (isa<ObjCInterfaceDecl>(this) &&
454             getASTContext().getLangOpts().ObjCRuntime.hasWeakClassImport()) {
455    return true;
456
457  // Nothing else.
458  } else {
459    return false;
460  }
461}
462
463bool Decl::isWeakImported() const {
464  bool IsDefinition;
465  if (!canBeWeakImported(IsDefinition))
466    return false;
467
468  for (attr_iterator A = attr_begin(), AEnd = attr_end(); A != AEnd; ++A) {
469    if (isa<WeakImportAttr>(*A))
470      return true;
471
472    if (AvailabilityAttr *Availability = dyn_cast<AvailabilityAttr>(*A)) {
473      if (CheckAvailability(getASTContext(), Availability, 0)
474                                                         == AR_NotYetIntroduced)
475        return true;
476    }
477  }
478
479  return false;
480}
481
482unsigned Decl::getIdentifierNamespaceForKind(Kind DeclKind) {
483  switch (DeclKind) {
484    case Function:
485    case CXXMethod:
486    case CXXConstructor:
487    case CXXDestructor:
488    case CXXConversion:
489    case EnumConstant:
490    case Var:
491    case ImplicitParam:
492    case ParmVar:
493    case NonTypeTemplateParm:
494    case ObjCMethod:
495    case ObjCProperty:
496    case MSProperty:
497      return IDNS_Ordinary;
498    case Label:
499      return IDNS_Label;
500    case IndirectField:
501      return IDNS_Ordinary | IDNS_Member;
502
503    case ObjCCompatibleAlias:
504    case ObjCInterface:
505      return IDNS_Ordinary | IDNS_Type;
506
507    case Typedef:
508    case TypeAlias:
509    case TypeAliasTemplate:
510    case UnresolvedUsingTypename:
511    case TemplateTypeParm:
512      return IDNS_Ordinary | IDNS_Type;
513
514    case UsingShadow:
515      return 0; // we'll actually overwrite this later
516
517    case UnresolvedUsingValue:
518      return IDNS_Ordinary | IDNS_Using;
519
520    case Using:
521      return IDNS_Using;
522
523    case ObjCProtocol:
524      return IDNS_ObjCProtocol;
525
526    case Field:
527    case ObjCAtDefsField:
528    case ObjCIvar:
529      return IDNS_Member;
530
531    case Record:
532    case CXXRecord:
533    case Enum:
534      return IDNS_Tag | IDNS_Type;
535
536    case Namespace:
537    case NamespaceAlias:
538      return IDNS_Namespace;
539
540    case FunctionTemplate:
541      return IDNS_Ordinary;
542
543    case ClassTemplate:
544    case TemplateTemplateParm:
545      return IDNS_Ordinary | IDNS_Tag | IDNS_Type;
546
547    // Never have names.
548    case Friend:
549    case FriendTemplate:
550    case AccessSpec:
551    case LinkageSpec:
552    case FileScopeAsm:
553    case StaticAssert:
554    case ObjCPropertyImpl:
555    case Block:
556    case Captured:
557    case TranslationUnit:
558
559    case UsingDirective:
560    case ClassTemplateSpecialization:
561    case ClassTemplatePartialSpecialization:
562    case ClassScopeFunctionSpecialization:
563    case ObjCImplementation:
564    case ObjCCategory:
565    case ObjCCategoryImpl:
566    case Import:
567    case OMPThreadPrivate:
568    case Empty:
569      // Never looked up by name.
570      return 0;
571  }
572
573  llvm_unreachable("Invalid DeclKind!");
574}
575
576void Decl::setAttrsImpl(const AttrVec &attrs, ASTContext &Ctx) {
577  assert(!HasAttrs && "Decl already contains attrs.");
578
579  AttrVec &AttrBlank = Ctx.getDeclAttrs(this);
580  assert(AttrBlank.empty() && "HasAttrs was wrong?");
581
582  AttrBlank = attrs;
583  HasAttrs = true;
584}
585
586void Decl::dropAttrs() {
587  if (!HasAttrs) return;
588
589  HasAttrs = false;
590  getASTContext().eraseDeclAttrs(this);
591}
592
593const AttrVec &Decl::getAttrs() const {
594  assert(HasAttrs && "No attrs to get!");
595  return getASTContext().getDeclAttrs(this);
596}
597
598Decl *Decl::castFromDeclContext (const DeclContext *D) {
599  Decl::Kind DK = D->getDeclKind();
600  switch(DK) {
601#define DECL(NAME, BASE)
602#define DECL_CONTEXT(NAME) \
603    case Decl::NAME:       \
604      return static_cast<NAME##Decl*>(const_cast<DeclContext*>(D));
605#define DECL_CONTEXT_BASE(NAME)
606#include "clang/AST/DeclNodes.inc"
607    default:
608#define DECL(NAME, BASE)
609#define DECL_CONTEXT_BASE(NAME)                  \
610      if (DK >= first##NAME && DK <= last##NAME) \
611        return static_cast<NAME##Decl*>(const_cast<DeclContext*>(D));
612#include "clang/AST/DeclNodes.inc"
613      llvm_unreachable("a decl that inherits DeclContext isn't handled");
614  }
615}
616
617DeclContext *Decl::castToDeclContext(const Decl *D) {
618  Decl::Kind DK = D->getKind();
619  switch(DK) {
620#define DECL(NAME, BASE)
621#define DECL_CONTEXT(NAME) \
622    case Decl::NAME:       \
623      return static_cast<NAME##Decl*>(const_cast<Decl*>(D));
624#define DECL_CONTEXT_BASE(NAME)
625#include "clang/AST/DeclNodes.inc"
626    default:
627#define DECL(NAME, BASE)
628#define DECL_CONTEXT_BASE(NAME)                                   \
629      if (DK >= first##NAME && DK <= last##NAME)                  \
630        return static_cast<NAME##Decl*>(const_cast<Decl*>(D));
631#include "clang/AST/DeclNodes.inc"
632      llvm_unreachable("a decl that inherits DeclContext isn't handled");
633  }
634}
635
636SourceLocation Decl::getBodyRBrace() const {
637  // Special handling of FunctionDecl to avoid de-serializing the body from PCH.
638  // FunctionDecl stores EndRangeLoc for this purpose.
639  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(this)) {
640    const FunctionDecl *Definition;
641    if (FD->hasBody(Definition))
642      return Definition->getSourceRange().getEnd();
643    return SourceLocation();
644  }
645
646  if (Stmt *Body = getBody())
647    return Body->getSourceRange().getEnd();
648
649  return SourceLocation();
650}
651
652void Decl::CheckAccessDeclContext() const {
653#ifndef NDEBUG
654  // Suppress this check if any of the following hold:
655  // 1. this is the translation unit (and thus has no parent)
656  // 2. this is a template parameter (and thus doesn't belong to its context)
657  // 3. this is a non-type template parameter
658  // 4. the context is not a record
659  // 5. it's invalid
660  // 6. it's a C++0x static_assert.
661  if (isa<TranslationUnitDecl>(this) ||
662      isa<TemplateTypeParmDecl>(this) ||
663      isa<NonTypeTemplateParmDecl>(this) ||
664      !isa<CXXRecordDecl>(getDeclContext()) ||
665      isInvalidDecl() ||
666      isa<StaticAssertDecl>(this) ||
667      // FIXME: a ParmVarDecl can have ClassTemplateSpecialization
668      // as DeclContext (?).
669      isa<ParmVarDecl>(this) ||
670      // FIXME: a ClassTemplateSpecialization or CXXRecordDecl can have
671      // AS_none as access specifier.
672      isa<CXXRecordDecl>(this) ||
673      isa<ClassScopeFunctionSpecializationDecl>(this))
674    return;
675
676  assert(Access != AS_none &&
677         "Access specifier is AS_none inside a record decl");
678#endif
679}
680
681static Decl::Kind getKind(const Decl *D) { return D->getKind(); }
682static Decl::Kind getKind(const DeclContext *DC) { return DC->getDeclKind(); }
683
684/// Starting at a given context (a Decl or DeclContext), look for a
685/// code context that is not a closure (a lambda, block, etc.).
686template <class T> static Decl *getNonClosureContext(T *D) {
687  if (getKind(D) == Decl::CXXMethod) {
688    CXXMethodDecl *MD = cast<CXXMethodDecl>(D);
689    if (MD->getOverloadedOperator() == OO_Call &&
690        MD->getParent()->isLambda())
691      return getNonClosureContext(MD->getParent()->getParent());
692    return MD;
693  } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
694    return FD;
695  } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
696    return MD;
697  } else if (BlockDecl *BD = dyn_cast<BlockDecl>(D)) {
698    return getNonClosureContext(BD->getParent());
699  } else if (CapturedDecl *CD = dyn_cast<CapturedDecl>(D)) {
700    return getNonClosureContext(CD->getParent());
701  } else {
702    return 0;
703  }
704}
705
706Decl *Decl::getNonClosureContext() {
707  return ::getNonClosureContext(this);
708}
709
710Decl *DeclContext::getNonClosureAncestor() {
711  return ::getNonClosureContext(this);
712}
713
714//===----------------------------------------------------------------------===//
715// DeclContext Implementation
716//===----------------------------------------------------------------------===//
717
718bool DeclContext::classof(const Decl *D) {
719  switch (D->getKind()) {
720#define DECL(NAME, BASE)
721#define DECL_CONTEXT(NAME) case Decl::NAME:
722#define DECL_CONTEXT_BASE(NAME)
723#include "clang/AST/DeclNodes.inc"
724      return true;
725    default:
726#define DECL(NAME, BASE)
727#define DECL_CONTEXT_BASE(NAME)                 \
728      if (D->getKind() >= Decl::first##NAME &&  \
729          D->getKind() <= Decl::last##NAME)     \
730        return true;
731#include "clang/AST/DeclNodes.inc"
732      return false;
733  }
734}
735
736DeclContext::~DeclContext() { }
737
738/// \brief Find the parent context of this context that will be
739/// used for unqualified name lookup.
740///
741/// Generally, the parent lookup context is the semantic context. However, for
742/// a friend function the parent lookup context is the lexical context, which
743/// is the class in which the friend is declared.
744DeclContext *DeclContext::getLookupParent() {
745  // FIXME: Find a better way to identify friends
746  if (isa<FunctionDecl>(this))
747    if (getParent()->getRedeclContext()->isFileContext() &&
748        getLexicalParent()->getRedeclContext()->isRecord())
749      return getLexicalParent();
750
751  return getParent();
752}
753
754bool DeclContext::isInlineNamespace() const {
755  return isNamespace() &&
756         cast<NamespaceDecl>(this)->isInline();
757}
758
759bool DeclContext::isDependentContext() const {
760  if (isFileContext())
761    return false;
762
763  if (isa<ClassTemplatePartialSpecializationDecl>(this))
764    return true;
765
766  if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(this)) {
767    if (Record->getDescribedClassTemplate())
768      return true;
769
770    if (Record->isDependentLambda())
771      return true;
772  }
773
774  if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(this)) {
775    if (Function->getDescribedFunctionTemplate())
776      return true;
777
778    // Friend function declarations are dependent if their *lexical*
779    // context is dependent.
780    if (cast<Decl>(this)->getFriendObjectKind())
781      return getLexicalParent()->isDependentContext();
782  }
783
784  return getParent() && getParent()->isDependentContext();
785}
786
787bool DeclContext::isTransparentContext() const {
788  if (DeclKind == Decl::Enum)
789    return !cast<EnumDecl>(this)->isScoped();
790  else if (DeclKind == Decl::LinkageSpec)
791    return true;
792
793  return false;
794}
795
796bool DeclContext::Encloses(const DeclContext *DC) const {
797  if (getPrimaryContext() != this)
798    return getPrimaryContext()->Encloses(DC);
799
800  for (; DC; DC = DC->getParent())
801    if (DC->getPrimaryContext() == this)
802      return true;
803  return false;
804}
805
806DeclContext *DeclContext::getPrimaryContext() {
807  switch (DeclKind) {
808  case Decl::TranslationUnit:
809  case Decl::LinkageSpec:
810  case Decl::Block:
811  case Decl::Captured:
812    // There is only one DeclContext for these entities.
813    return this;
814
815  case Decl::Namespace:
816    // The original namespace is our primary context.
817    return static_cast<NamespaceDecl*>(this)->getOriginalNamespace();
818
819  case Decl::ObjCMethod:
820    return this;
821
822  case Decl::ObjCInterface:
823    if (ObjCInterfaceDecl *Def = cast<ObjCInterfaceDecl>(this)->getDefinition())
824      return Def;
825
826    return this;
827
828  case Decl::ObjCProtocol:
829    if (ObjCProtocolDecl *Def = cast<ObjCProtocolDecl>(this)->getDefinition())
830      return Def;
831
832    return this;
833
834  case Decl::ObjCCategory:
835    return this;
836
837  case Decl::ObjCImplementation:
838  case Decl::ObjCCategoryImpl:
839    return this;
840
841  default:
842    if (DeclKind >= Decl::firstTag && DeclKind <= Decl::lastTag) {
843      // If this is a tag type that has a definition or is currently
844      // being defined, that definition is our primary context.
845      TagDecl *Tag = cast<TagDecl>(this);
846      assert(isa<TagType>(Tag->TypeForDecl) ||
847             isa<InjectedClassNameType>(Tag->TypeForDecl));
848
849      if (TagDecl *Def = Tag->getDefinition())
850        return Def;
851
852      if (!isa<InjectedClassNameType>(Tag->TypeForDecl)) {
853        const TagType *TagTy = cast<TagType>(Tag->TypeForDecl);
854        if (TagTy->isBeingDefined())
855          // FIXME: is it necessarily being defined in the decl
856          // that owns the type?
857          return TagTy->getDecl();
858      }
859
860      return Tag;
861    }
862
863    assert(DeclKind >= Decl::firstFunction && DeclKind <= Decl::lastFunction &&
864          "Unknown DeclContext kind");
865    return this;
866  }
867}
868
869void
870DeclContext::collectAllContexts(SmallVectorImpl<DeclContext *> &Contexts){
871  Contexts.clear();
872
873  if (DeclKind != Decl::Namespace) {
874    Contexts.push_back(this);
875    return;
876  }
877
878  NamespaceDecl *Self = static_cast<NamespaceDecl *>(this);
879  for (NamespaceDecl *N = Self->getMostRecentDecl(); N;
880       N = N->getPreviousDecl())
881    Contexts.push_back(N);
882
883  std::reverse(Contexts.begin(), Contexts.end());
884}
885
886std::pair<Decl *, Decl *>
887DeclContext::BuildDeclChain(ArrayRef<Decl*> Decls,
888                            bool FieldsAlreadyLoaded) {
889  // Build up a chain of declarations via the Decl::NextInContextAndBits field.
890  Decl *FirstNewDecl = 0;
891  Decl *PrevDecl = 0;
892  for (unsigned I = 0, N = Decls.size(); I != N; ++I) {
893    if (FieldsAlreadyLoaded && isa<FieldDecl>(Decls[I]))
894      continue;
895
896    Decl *D = Decls[I];
897    if (PrevDecl)
898      PrevDecl->NextInContextAndBits.setPointer(D);
899    else
900      FirstNewDecl = D;
901
902    PrevDecl = D;
903  }
904
905  return std::make_pair(FirstNewDecl, PrevDecl);
906}
907
908/// \brief We have just acquired external visible storage, and we already have
909/// built a lookup map. For every name in the map, pull in the new names from
910/// the external storage.
911void DeclContext::reconcileExternalVisibleStorage() {
912  assert(NeedToReconcileExternalVisibleStorage && LookupPtr.getPointer());
913  NeedToReconcileExternalVisibleStorage = false;
914
915  StoredDeclsMap &Map = *LookupPtr.getPointer();
916  ExternalASTSource *Source = getParentASTContext().getExternalSource();
917  for (StoredDeclsMap::iterator I = Map.begin(); I != Map.end(); ++I) {
918    I->second.removeExternalDecls();
919    Source->FindExternalVisibleDeclsByName(this, I->first);
920  }
921}
922
923/// \brief Load the declarations within this lexical storage from an
924/// external source.
925void
926DeclContext::LoadLexicalDeclsFromExternalStorage() const {
927  ExternalASTSource *Source = getParentASTContext().getExternalSource();
928  assert(hasExternalLexicalStorage() && Source && "No external storage?");
929
930  // Notify that we have a DeclContext that is initializing.
931  ExternalASTSource::Deserializing ADeclContext(Source);
932
933  // Load the external declarations, if any.
934  SmallVector<Decl*, 64> Decls;
935  ExternalLexicalStorage = false;
936  switch (Source->FindExternalLexicalDecls(this, Decls)) {
937  case ELR_Success:
938    break;
939
940  case ELR_Failure:
941  case ELR_AlreadyLoaded:
942    return;
943  }
944
945  if (Decls.empty())
946    return;
947
948  // We may have already loaded just the fields of this record, in which case
949  // we need to ignore them.
950  bool FieldsAlreadyLoaded = false;
951  if (const RecordDecl *RD = dyn_cast<RecordDecl>(this))
952    FieldsAlreadyLoaded = RD->LoadedFieldsFromExternalStorage;
953
954  // Splice the newly-read declarations into the beginning of the list
955  // of declarations.
956  Decl *ExternalFirst, *ExternalLast;
957  llvm::tie(ExternalFirst, ExternalLast) = BuildDeclChain(Decls,
958                                                          FieldsAlreadyLoaded);
959  ExternalLast->NextInContextAndBits.setPointer(FirstDecl);
960  FirstDecl = ExternalFirst;
961  if (!LastDecl)
962    LastDecl = ExternalLast;
963}
964
965DeclContext::lookup_result
966ExternalASTSource::SetNoExternalVisibleDeclsForName(const DeclContext *DC,
967                                                    DeclarationName Name) {
968  ASTContext &Context = DC->getParentASTContext();
969  StoredDeclsMap *Map;
970  if (!(Map = DC->LookupPtr.getPointer()))
971    Map = DC->CreateStoredDeclsMap(Context);
972
973  // Add an entry to the map for this name, if it's not already present.
974  (*Map)[Name];
975
976  return DeclContext::lookup_result();
977}
978
979DeclContext::lookup_result
980ExternalASTSource::SetExternalVisibleDeclsForName(const DeclContext *DC,
981                                                  DeclarationName Name,
982                                                  ArrayRef<NamedDecl*> Decls) {
983  ASTContext &Context = DC->getParentASTContext();
984  StoredDeclsMap *Map;
985  if (!(Map = DC->LookupPtr.getPointer()))
986    Map = DC->CreateStoredDeclsMap(Context);
987
988  StoredDeclsList &List = (*Map)[Name];
989
990  // Clear out any old external visible declarations, to avoid quadratic
991  // performance in the redeclaration checks below.
992  List.removeExternalDecls();
993
994  if (!List.isNull()) {
995    // We have both existing declarations and new declarations for this name.
996    // Some of the declarations may simply replace existing ones. Handle those
997    // first.
998    llvm::SmallVector<unsigned, 8> Skip;
999    for (unsigned I = 0, N = Decls.size(); I != N; ++I)
1000      if (List.HandleRedeclaration(Decls[I]))
1001        Skip.push_back(I);
1002    Skip.push_back(Decls.size());
1003
1004    // Add in any new declarations.
1005    unsigned SkipPos = 0;
1006    for (unsigned I = 0, N = Decls.size(); I != N; ++I) {
1007      if (I == Skip[SkipPos])
1008        ++SkipPos;
1009      else
1010        List.AddSubsequentDecl(Decls[I]);
1011    }
1012  } else {
1013    // Convert the array to a StoredDeclsList.
1014    for (ArrayRef<NamedDecl*>::iterator
1015           I = Decls.begin(), E = Decls.end(); I != E; ++I) {
1016      if (List.isNull())
1017        List.setOnlyValue(*I);
1018      else
1019        List.AddSubsequentDecl(*I);
1020    }
1021  }
1022
1023  return List.getLookupResult();
1024}
1025
1026DeclContext::decl_iterator DeclContext::noload_decls_begin() const {
1027  return decl_iterator(FirstDecl);
1028}
1029
1030DeclContext::decl_iterator DeclContext::decls_begin() const {
1031  if (hasExternalLexicalStorage())
1032    LoadLexicalDeclsFromExternalStorage();
1033
1034  return decl_iterator(FirstDecl);
1035}
1036
1037bool DeclContext::decls_empty() const {
1038  if (hasExternalLexicalStorage())
1039    LoadLexicalDeclsFromExternalStorage();
1040
1041  return !FirstDecl;
1042}
1043
1044bool DeclContext::containsDecl(Decl *D) const {
1045  return (D->getLexicalDeclContext() == this &&
1046          (D->NextInContextAndBits.getPointer() || D == LastDecl));
1047}
1048
1049void DeclContext::removeDecl(Decl *D) {
1050  assert(D->getLexicalDeclContext() == this &&
1051         "decl being removed from non-lexical context");
1052  assert((D->NextInContextAndBits.getPointer() || D == LastDecl) &&
1053         "decl is not in decls list");
1054
1055  // Remove D from the decl chain.  This is O(n) but hopefully rare.
1056  if (D == FirstDecl) {
1057    if (D == LastDecl)
1058      FirstDecl = LastDecl = 0;
1059    else
1060      FirstDecl = D->NextInContextAndBits.getPointer();
1061  } else {
1062    for (Decl *I = FirstDecl; true; I = I->NextInContextAndBits.getPointer()) {
1063      assert(I && "decl not found in linked list");
1064      if (I->NextInContextAndBits.getPointer() == D) {
1065        I->NextInContextAndBits.setPointer(D->NextInContextAndBits.getPointer());
1066        if (D == LastDecl) LastDecl = I;
1067        break;
1068      }
1069    }
1070  }
1071
1072  // Mark that D is no longer in the decl chain.
1073  D->NextInContextAndBits.setPointer(0);
1074
1075  // Remove D from the lookup table if necessary.
1076  if (isa<NamedDecl>(D)) {
1077    NamedDecl *ND = cast<NamedDecl>(D);
1078
1079    // Remove only decls that have a name
1080    if (!ND->getDeclName()) return;
1081
1082    StoredDeclsMap *Map = getPrimaryContext()->LookupPtr.getPointer();
1083    if (!Map) return;
1084
1085    StoredDeclsMap::iterator Pos = Map->find(ND->getDeclName());
1086    assert(Pos != Map->end() && "no lookup entry for decl");
1087    if (Pos->second.getAsVector() || Pos->second.getAsDecl() == ND)
1088      Pos->second.remove(ND);
1089  }
1090}
1091
1092void DeclContext::addHiddenDecl(Decl *D) {
1093  assert(D->getLexicalDeclContext() == this &&
1094         "Decl inserted into wrong lexical context");
1095  assert(!D->getNextDeclInContext() && D != LastDecl &&
1096         "Decl already inserted into a DeclContext");
1097
1098  if (FirstDecl) {
1099    LastDecl->NextInContextAndBits.setPointer(D);
1100    LastDecl = D;
1101  } else {
1102    FirstDecl = LastDecl = D;
1103  }
1104
1105  // Notify a C++ record declaration that we've added a member, so it can
1106  // update it's class-specific state.
1107  if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(this))
1108    Record->addedMember(D);
1109
1110  // If this is a newly-created (not de-serialized) import declaration, wire
1111  // it in to the list of local import declarations.
1112  if (!D->isFromASTFile()) {
1113    if (ImportDecl *Import = dyn_cast<ImportDecl>(D))
1114      D->getASTContext().addedLocalImportDecl(Import);
1115  }
1116}
1117
1118void DeclContext::addDecl(Decl *D) {
1119  addHiddenDecl(D);
1120
1121  if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
1122    ND->getDeclContext()->getPrimaryContext()->
1123        makeDeclVisibleInContextWithFlags(ND, false, true);
1124}
1125
1126void DeclContext::addDeclInternal(Decl *D) {
1127  addHiddenDecl(D);
1128
1129  if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
1130    ND->getDeclContext()->getPrimaryContext()->
1131        makeDeclVisibleInContextWithFlags(ND, true, true);
1132}
1133
1134/// shouldBeHidden - Determine whether a declaration which was declared
1135/// within its semantic context should be invisible to qualified name lookup.
1136static bool shouldBeHidden(NamedDecl *D) {
1137  // Skip unnamed declarations.
1138  if (!D->getDeclName())
1139    return true;
1140
1141  // Skip entities that can't be found by name lookup into a particular
1142  // context.
1143  if ((D->getIdentifierNamespace() == 0 && !isa<UsingDirectiveDecl>(D)) ||
1144      D->isTemplateParameter())
1145    return true;
1146
1147  // Skip template specializations.
1148  // FIXME: This feels like a hack. Should DeclarationName support
1149  // template-ids, or is there a better way to keep specializations
1150  // from being visible?
1151  if (isa<ClassTemplateSpecializationDecl>(D))
1152    return true;
1153  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
1154    if (FD->isFunctionTemplateSpecialization())
1155      return true;
1156
1157  return false;
1158}
1159
1160/// buildLookup - Build the lookup data structure with all of the
1161/// declarations in this DeclContext (and any other contexts linked
1162/// to it or transparent contexts nested within it) and return it.
1163StoredDeclsMap *DeclContext::buildLookup() {
1164  assert(this == getPrimaryContext() && "buildLookup called on non-primary DC");
1165
1166  // FIXME: Should we keep going if hasExternalVisibleStorage?
1167  if (!LookupPtr.getInt())
1168    return LookupPtr.getPointer();
1169
1170  SmallVector<DeclContext *, 2> Contexts;
1171  collectAllContexts(Contexts);
1172  for (unsigned I = 0, N = Contexts.size(); I != N; ++I)
1173    buildLookupImpl<&DeclContext::decls_begin,
1174                    &DeclContext::decls_end>(Contexts[I]);
1175
1176  // We no longer have any lazy decls.
1177  LookupPtr.setInt(false);
1178  NeedToReconcileExternalVisibleStorage = false;
1179  return LookupPtr.getPointer();
1180}
1181
1182/// buildLookupImpl - Build part of the lookup data structure for the
1183/// declarations contained within DCtx, which will either be this
1184/// DeclContext, a DeclContext linked to it, or a transparent context
1185/// nested within it.
1186template<DeclContext::decl_iterator (DeclContext::*Begin)() const,
1187         DeclContext::decl_iterator (DeclContext::*End)() const>
1188void DeclContext::buildLookupImpl(DeclContext *DCtx) {
1189  for (decl_iterator I = (DCtx->*Begin)(), E = (DCtx->*End)();
1190       I != E; ++I) {
1191    Decl *D = *I;
1192
1193    // Insert this declaration into the lookup structure, but only if
1194    // it's semantically within its decl context. Any other decls which
1195    // should be found in this context are added eagerly.
1196    //
1197    // If it's from an AST file, don't add it now. It'll get handled by
1198    // FindExternalVisibleDeclsByName if needed. Exception: if we're not
1199    // in C++, we do not track external visible decls for the TU, so in
1200    // that case we need to collect them all here.
1201    if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
1202      if (ND->getDeclContext() == DCtx && !shouldBeHidden(ND) &&
1203          (!ND->isFromASTFile() ||
1204           (isTranslationUnit() &&
1205            !getParentASTContext().getLangOpts().CPlusPlus)))
1206        makeDeclVisibleInContextImpl(ND, false);
1207
1208    // If this declaration is itself a transparent declaration context
1209    // or inline namespace, add the members of this declaration of that
1210    // context (recursively).
1211    if (DeclContext *InnerCtx = dyn_cast<DeclContext>(D))
1212      if (InnerCtx->isTransparentContext() || InnerCtx->isInlineNamespace())
1213        buildLookupImpl<Begin, End>(InnerCtx);
1214  }
1215}
1216
1217DeclContext::lookup_result
1218DeclContext::lookup(DeclarationName Name) {
1219  assert(DeclKind != Decl::LinkageSpec &&
1220         "Should not perform lookups into linkage specs!");
1221
1222  DeclContext *PrimaryContext = getPrimaryContext();
1223  if (PrimaryContext != this)
1224    return PrimaryContext->lookup(Name);
1225
1226  if (hasExternalVisibleStorage()) {
1227    StoredDeclsMap *Map = LookupPtr.getPointer();
1228    if (LookupPtr.getInt())
1229      Map = buildLookup();
1230    else if (NeedToReconcileExternalVisibleStorage)
1231      reconcileExternalVisibleStorage();
1232
1233    if (!Map)
1234      Map = CreateStoredDeclsMap(getParentASTContext());
1235
1236    // If a PCH/module has a result for this name, and we have a local
1237    // declaration, we will have imported the PCH/module result when adding the
1238    // local declaration or when reconciling the module.
1239    std::pair<StoredDeclsMap::iterator, bool> R =
1240        Map->insert(std::make_pair(Name, StoredDeclsList()));
1241    if (!R.second)
1242      return R.first->second.getLookupResult();
1243
1244    ExternalASTSource *Source = getParentASTContext().getExternalSource();
1245    if (Source->FindExternalVisibleDeclsByName(this, Name)) {
1246      if (StoredDeclsMap *Map = LookupPtr.getPointer()) {
1247        StoredDeclsMap::iterator I = Map->find(Name);
1248        if (I != Map->end())
1249          return I->second.getLookupResult();
1250      }
1251    }
1252
1253    return lookup_result(lookup_iterator(0), lookup_iterator(0));
1254  }
1255
1256  StoredDeclsMap *Map = LookupPtr.getPointer();
1257  if (LookupPtr.getInt())
1258    Map = buildLookup();
1259
1260  if (!Map)
1261    return lookup_result(lookup_iterator(0), lookup_iterator(0));
1262
1263  StoredDeclsMap::iterator I = Map->find(Name);
1264  if (I == Map->end())
1265    return lookup_result(lookup_iterator(0), lookup_iterator(0));
1266
1267  return I->second.getLookupResult();
1268}
1269
1270DeclContext::lookup_result
1271DeclContext::noload_lookup(DeclarationName Name) {
1272  assert(DeclKind != Decl::LinkageSpec &&
1273         "Should not perform lookups into linkage specs!");
1274  if (!hasExternalVisibleStorage())
1275    return lookup(Name);
1276
1277  DeclContext *PrimaryContext = getPrimaryContext();
1278  if (PrimaryContext != this)
1279    return PrimaryContext->noload_lookup(Name);
1280
1281  StoredDeclsMap *Map = LookupPtr.getPointer();
1282  if (LookupPtr.getInt()) {
1283    // Carefully build the lookup map, without deserializing anything.
1284    SmallVector<DeclContext *, 2> Contexts;
1285    collectAllContexts(Contexts);
1286    for (unsigned I = 0, N = Contexts.size(); I != N; ++I)
1287      buildLookupImpl<&DeclContext::noload_decls_begin,
1288                      &DeclContext::noload_decls_end>(Contexts[I]);
1289
1290    // We no longer have any lazy decls.
1291    LookupPtr.setInt(false);
1292
1293    // There may now be names for which we have local decls but are
1294    // missing the external decls.
1295    NeedToReconcileExternalVisibleStorage = true;
1296
1297    Map = LookupPtr.getPointer();
1298  }
1299
1300  if (!Map)
1301    return lookup_result(lookup_iterator(0), lookup_iterator(0));
1302
1303  StoredDeclsMap::iterator I = Map->find(Name);
1304  return I != Map->end()
1305             ? I->second.getLookupResult()
1306             : lookup_result(lookup_iterator(0), lookup_iterator(0));
1307}
1308
1309void DeclContext::localUncachedLookup(DeclarationName Name,
1310                                      SmallVectorImpl<NamedDecl *> &Results) {
1311  Results.clear();
1312
1313  // If there's no external storage, just perform a normal lookup and copy
1314  // the results.
1315  if (!hasExternalVisibleStorage() && !hasExternalLexicalStorage() && Name) {
1316    lookup_result LookupResults = lookup(Name);
1317    Results.insert(Results.end(), LookupResults.begin(), LookupResults.end());
1318    return;
1319  }
1320
1321  // If we have a lookup table, check there first. Maybe we'll get lucky.
1322  if (Name && !LookupPtr.getInt()) {
1323    if (StoredDeclsMap *Map = LookupPtr.getPointer()) {
1324      StoredDeclsMap::iterator Pos = Map->find(Name);
1325      if (Pos != Map->end()) {
1326        Results.insert(Results.end(),
1327                       Pos->second.getLookupResult().begin(),
1328                       Pos->second.getLookupResult().end());
1329        return;
1330      }
1331    }
1332  }
1333
1334  // Slow case: grovel through the declarations in our chain looking for
1335  // matches.
1336  for (Decl *D = FirstDecl; D; D = D->getNextDeclInContext()) {
1337    if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
1338      if (ND->getDeclName() == Name)
1339        Results.push_back(ND);
1340  }
1341}
1342
1343DeclContext *DeclContext::getRedeclContext() {
1344  DeclContext *Ctx = this;
1345  // Skip through transparent contexts.
1346  while (Ctx->isTransparentContext())
1347    Ctx = Ctx->getParent();
1348  return Ctx;
1349}
1350
1351DeclContext *DeclContext::getEnclosingNamespaceContext() {
1352  DeclContext *Ctx = this;
1353  // Skip through non-namespace, non-translation-unit contexts.
1354  while (!Ctx->isFileContext())
1355    Ctx = Ctx->getParent();
1356  return Ctx->getPrimaryContext();
1357}
1358
1359bool DeclContext::InEnclosingNamespaceSetOf(const DeclContext *O) const {
1360  // For non-file contexts, this is equivalent to Equals.
1361  if (!isFileContext())
1362    return O->Equals(this);
1363
1364  do {
1365    if (O->Equals(this))
1366      return true;
1367
1368    const NamespaceDecl *NS = dyn_cast<NamespaceDecl>(O);
1369    if (!NS || !NS->isInline())
1370      break;
1371    O = NS->getParent();
1372  } while (O);
1373
1374  return false;
1375}
1376
1377void DeclContext::makeDeclVisibleInContext(NamedDecl *D) {
1378  DeclContext *PrimaryDC = this->getPrimaryContext();
1379  DeclContext *DeclDC = D->getDeclContext()->getPrimaryContext();
1380  // If the decl is being added outside of its semantic decl context, we
1381  // need to ensure that we eagerly build the lookup information for it.
1382  PrimaryDC->makeDeclVisibleInContextWithFlags(D, false, PrimaryDC == DeclDC);
1383}
1384
1385void DeclContext::makeDeclVisibleInContextWithFlags(NamedDecl *D, bool Internal,
1386                                                    bool Recoverable) {
1387  assert(this == getPrimaryContext() && "expected a primary DC");
1388
1389  // Skip declarations within functions.
1390  // FIXME: We shouldn't need to build lookup tables for function declarations
1391  // ever, and we can't do so correctly because we can't model the nesting of
1392  // scopes which occurs within functions. We use "qualified" lookup into
1393  // function declarations when handling friend declarations inside nested
1394  // classes, and consequently accept the following invalid code:
1395  //
1396  //   void f() { void g(); { int g; struct S { friend void g(); }; } }
1397  if (isFunctionOrMethod() && !isa<FunctionDecl>(D))
1398    return;
1399
1400  // Skip declarations which should be invisible to name lookup.
1401  if (shouldBeHidden(D))
1402    return;
1403
1404  // If we already have a lookup data structure, perform the insertion into
1405  // it. If we might have externally-stored decls with this name, look them
1406  // up and perform the insertion. If this decl was declared outside its
1407  // semantic context, buildLookup won't add it, so add it now.
1408  //
1409  // FIXME: As a performance hack, don't add such decls into the translation
1410  // unit unless we're in C++, since qualified lookup into the TU is never
1411  // performed.
1412  if (LookupPtr.getPointer() || hasExternalVisibleStorage() ||
1413      ((!Recoverable || D->getDeclContext() != D->getLexicalDeclContext()) &&
1414       (getParentASTContext().getLangOpts().CPlusPlus ||
1415        !isTranslationUnit()))) {
1416    // If we have lazily omitted any decls, they might have the same name as
1417    // the decl which we are adding, so build a full lookup table before adding
1418    // this decl.
1419    buildLookup();
1420    makeDeclVisibleInContextImpl(D, Internal);
1421  } else {
1422    LookupPtr.setInt(true);
1423  }
1424
1425  // If we are a transparent context or inline namespace, insert into our
1426  // parent context, too. This operation is recursive.
1427  if (isTransparentContext() || isInlineNamespace())
1428    getParent()->getPrimaryContext()->
1429        makeDeclVisibleInContextWithFlags(D, Internal, Recoverable);
1430
1431  Decl *DCAsDecl = cast<Decl>(this);
1432  // Notify that a decl was made visible unless we are a Tag being defined.
1433  if (!(isa<TagDecl>(DCAsDecl) && cast<TagDecl>(DCAsDecl)->isBeingDefined()))
1434    if (ASTMutationListener *L = DCAsDecl->getASTMutationListener())
1435      L->AddedVisibleDecl(this, D);
1436}
1437
1438void DeclContext::makeDeclVisibleInContextImpl(NamedDecl *D, bool Internal) {
1439  // Find or create the stored declaration map.
1440  StoredDeclsMap *Map = LookupPtr.getPointer();
1441  if (!Map) {
1442    ASTContext *C = &getParentASTContext();
1443    Map = CreateStoredDeclsMap(*C);
1444  }
1445
1446  // If there is an external AST source, load any declarations it knows about
1447  // with this declaration's name.
1448  // If the lookup table contains an entry about this name it means that we
1449  // have already checked the external source.
1450  if (!Internal)
1451    if (ExternalASTSource *Source = getParentASTContext().getExternalSource())
1452      if (hasExternalVisibleStorage() &&
1453          Map->find(D->getDeclName()) == Map->end())
1454        Source->FindExternalVisibleDeclsByName(this, D->getDeclName());
1455
1456  // Insert this declaration into the map.
1457  StoredDeclsList &DeclNameEntries = (*Map)[D->getDeclName()];
1458  if (DeclNameEntries.isNull()) {
1459    DeclNameEntries.setOnlyValue(D);
1460    return;
1461  }
1462
1463  if (DeclNameEntries.HandleRedeclaration(D)) {
1464    // This declaration has replaced an existing one for which
1465    // declarationReplaces returns true.
1466    return;
1467  }
1468
1469  // Put this declaration into the appropriate slot.
1470  DeclNameEntries.AddSubsequentDecl(D);
1471}
1472
1473/// Returns iterator range [First, Last) of UsingDirectiveDecls stored within
1474/// this context.
1475DeclContext::udir_iterator_range
1476DeclContext::getUsingDirectives() const {
1477  // FIXME: Use something more efficient than normal lookup for using
1478  // directives. In C++, using directives are looked up more than anything else.
1479  lookup_const_result Result = lookup(UsingDirectiveDecl::getName());
1480  return udir_iterator_range(reinterpret_cast<udir_iterator>(Result.begin()),
1481                             reinterpret_cast<udir_iterator>(Result.end()));
1482}
1483
1484//===----------------------------------------------------------------------===//
1485// Creation and Destruction of StoredDeclsMaps.                               //
1486//===----------------------------------------------------------------------===//
1487
1488StoredDeclsMap *DeclContext::CreateStoredDeclsMap(ASTContext &C) const {
1489  assert(!LookupPtr.getPointer() && "context already has a decls map");
1490  assert(getPrimaryContext() == this &&
1491         "creating decls map on non-primary context");
1492
1493  StoredDeclsMap *M;
1494  bool Dependent = isDependentContext();
1495  if (Dependent)
1496    M = new DependentStoredDeclsMap();
1497  else
1498    M = new StoredDeclsMap();
1499  M->Previous = C.LastSDM;
1500  C.LastSDM = llvm::PointerIntPair<StoredDeclsMap*,1>(M, Dependent);
1501  LookupPtr.setPointer(M);
1502  return M;
1503}
1504
1505void ASTContext::ReleaseDeclContextMaps() {
1506  // It's okay to delete DependentStoredDeclsMaps via a StoredDeclsMap
1507  // pointer because the subclass doesn't add anything that needs to
1508  // be deleted.
1509  StoredDeclsMap::DestroyAll(LastSDM.getPointer(), LastSDM.getInt());
1510}
1511
1512void StoredDeclsMap::DestroyAll(StoredDeclsMap *Map, bool Dependent) {
1513  while (Map) {
1514    // Advance the iteration before we invalidate memory.
1515    llvm::PointerIntPair<StoredDeclsMap*,1> Next = Map->Previous;
1516
1517    if (Dependent)
1518      delete static_cast<DependentStoredDeclsMap*>(Map);
1519    else
1520      delete Map;
1521
1522    Map = Next.getPointer();
1523    Dependent = Next.getInt();
1524  }
1525}
1526
1527DependentDiagnostic *DependentDiagnostic::Create(ASTContext &C,
1528                                                 DeclContext *Parent,
1529                                           const PartialDiagnostic &PDiag) {
1530  assert(Parent->isDependentContext()
1531         && "cannot iterate dependent diagnostics of non-dependent context");
1532  Parent = Parent->getPrimaryContext();
1533  if (!Parent->LookupPtr.getPointer())
1534    Parent->CreateStoredDeclsMap(C);
1535
1536  DependentStoredDeclsMap *Map
1537    = static_cast<DependentStoredDeclsMap*>(Parent->LookupPtr.getPointer());
1538
1539  // Allocate the copy of the PartialDiagnostic via the ASTContext's
1540  // BumpPtrAllocator, rather than the ASTContext itself.
1541  PartialDiagnostic::Storage *DiagStorage = 0;
1542  if (PDiag.hasStorage())
1543    DiagStorage = new (C) PartialDiagnostic::Storage;
1544
1545  DependentDiagnostic *DD = new (C) DependentDiagnostic(PDiag, DiagStorage);
1546
1547  // TODO: Maybe we shouldn't reverse the order during insertion.
1548  DD->NextDiagnostic = Map->FirstDiagnostic;
1549  Map->FirstDiagnostic = DD;
1550
1551  return DD;
1552}
1553