DeclBase.cpp revision e664977aca2a05a77abab5a06dc0fb69e870cfb9 
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/Decl.h"
16#include "clang/AST/DeclContextInternals.h"
17#include "clang/AST/DeclCXX.h"
18#include "clang/AST/DeclFriend.h"
19#include "clang/AST/DeclObjC.h"
20#include "clang/AST/DeclTemplate.h"
21#include "clang/AST/DependentDiagnostic.h"
22#include "clang/AST/ExternalASTSource.h"
23#include "clang/AST/ASTContext.h"
24#include "clang/AST/Type.h"
25#include "clang/AST/Stmt.h"
26#include "clang/AST/StmtCXX.h"
27#include "clang/AST/ASTMutationListener.h"
28#include "clang/Basic/TargetInfo.h"
29#include "llvm/ADT/DenseMap.h"
30#include "llvm/Support/raw_ostream.h"
31#include <algorithm>
32using namespace clang;
33
34//===----------------------------------------------------------------------===//
35//  Statistics
36//===----------------------------------------------------------------------===//
37
38#define DECL(DERIVED, BASE) static int n##DERIVED##s = 0;
39#define ABSTRACT_DECL(DECL)
40#include "clang/AST/DeclNodes.inc"
41
42static bool StatSwitch = false;
43
44const char *Decl::getDeclKindName() const {
45  switch (DeclKind) {
46  default: llvm_unreachable("Declaration not in DeclNodes.inc!");
47#define DECL(DERIVED, BASE) case DERIVED: return #DERIVED;
48#define ABSTRACT_DECL(DECL)
49#include "clang/AST/DeclNodes.inc"
50  }
51}
52
53void Decl::setInvalidDecl(bool Invalid) {
54  InvalidDecl = Invalid;
55  if (Invalid) {
56    // Defensive maneuver for ill-formed code: we're likely not to make it to
57    // a point where we set the access specifier, so default it to "public"
58    // to avoid triggering asserts elsewhere in the front end.
59    setAccess(AS_public);
60  }
61}
62
63const char *DeclContext::getDeclKindName() const {
64  switch (DeclKind) {
65  default: llvm_unreachable("Declaration context not in DeclNodes.inc!");
66#define DECL(DERIVED, BASE) case Decl::DERIVED: return #DERIVED;
67#define ABSTRACT_DECL(DECL)
68#include "clang/AST/DeclNodes.inc"
69  }
70}
71
72bool Decl::CollectingStats(bool Enable) {
73  if (Enable) StatSwitch = true;
74  return StatSwitch;
75}
76
77void Decl::PrintStats() {
78  llvm::errs() << "\n*** Decl Stats:\n";
79
80  int totalDecls = 0;
81#define DECL(DERIVED, BASE) totalDecls += n##DERIVED##s;
82#define ABSTRACT_DECL(DECL)
83#include "clang/AST/DeclNodes.inc"
84  llvm::errs() << "  " << totalDecls << " decls total.\n";
85
86  int totalBytes = 0;
87#define DECL(DERIVED, BASE)                                             \
88  if (n##DERIVED##s > 0) {                                              \
89    totalBytes += (int)(n##DERIVED##s * sizeof(DERIVED##Decl));         \
90    llvm::errs() << "    " << n##DERIVED##s << " " #DERIVED " decls, "  \
91                 << sizeof(DERIVED##Decl) << " each ("                  \
92                 << n##DERIVED##s * sizeof(DERIVED##Decl)               \
93                 << " bytes)\n";                                        \
94  }
95#define ABSTRACT_DECL(DECL)
96#include "clang/AST/DeclNodes.inc"
97
98  llvm::errs() << "Total bytes = " << totalBytes << "\n";
99}
100
101void Decl::add(Kind k) {
102  switch (k) {
103  default: llvm_unreachable("Declaration not in DeclNodes.inc!");
104#define DECL(DERIVED, BASE) case DERIVED: ++n##DERIVED##s; break;
105#define ABSTRACT_DECL(DECL)
106#include "clang/AST/DeclNodes.inc"
107  }
108}
109
110bool Decl::isTemplateParameterPack() const {
111  if (const TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(this))
112    return TTP->isParameterPack();
113  if (const NonTypeTemplateParmDecl *NTTP
114                                = dyn_cast<NonTypeTemplateParmDecl>(this))
115    return NTTP->isParameterPack();
116  if (const TemplateTemplateParmDecl *TTP
117                                    = dyn_cast<TemplateTemplateParmDecl>(this))
118    return TTP->isParameterPack();
119  return false;
120}
121
122bool Decl::isParameterPack() const {
123  if (const ParmVarDecl *Parm = dyn_cast<ParmVarDecl>(this))
124    return Parm->isParameterPack();
125
126  return isTemplateParameterPack();
127}
128
129bool Decl::isFunctionOrFunctionTemplate() const {
130  if (const UsingShadowDecl *UD = dyn_cast<UsingShadowDecl>(this))
131    return UD->getTargetDecl()->isFunctionOrFunctionTemplate();
132
133  return isa<FunctionDecl>(this) || isa<FunctionTemplateDecl>(this);
134}
135
136bool Decl::isTemplateDecl() const {
137  return isa<TemplateDecl>(this);
138}
139
140const DeclContext *Decl::getParentFunctionOrMethod() const {
141  for (const DeclContext *DC = getDeclContext();
142       DC && !DC->isTranslationUnit() && !DC->isNamespace();
143       DC = DC->getParent())
144    if (DC->isFunctionOrMethod())
145      return DC;
146
147  return 0;
148}
149
150
151//===----------------------------------------------------------------------===//
152// PrettyStackTraceDecl Implementation
153//===----------------------------------------------------------------------===//
154
155void PrettyStackTraceDecl::print(raw_ostream &OS) const {
156  SourceLocation TheLoc = Loc;
157  if (TheLoc.isInvalid() && TheDecl)
158    TheLoc = TheDecl->getLocation();
159
160  if (TheLoc.isValid()) {
161    TheLoc.print(OS, SM);
162    OS << ": ";
163  }
164
165  OS << Message;
166
167  if (const NamedDecl *DN = dyn_cast_or_null<NamedDecl>(TheDecl))
168    OS << " '" << DN->getQualifiedNameAsString() << '\'';
169  OS << '\n';
170}
171
172//===----------------------------------------------------------------------===//
173// Decl Implementation
174//===----------------------------------------------------------------------===//
175
176// Out-of-line virtual method providing a home for Decl.
177Decl::~Decl() { }
178
179void Decl::setDeclContext(DeclContext *DC) {
180  DeclCtx = DC;
181}
182
183void Decl::setLexicalDeclContext(DeclContext *DC) {
184  if (DC == getLexicalDeclContext())
185    return;
186
187  if (isInSemaDC()) {
188    MultipleDC *MDC = new (getASTContext()) MultipleDC();
189    MDC->SemanticDC = getDeclContext();
190    MDC->LexicalDC = DC;
191    DeclCtx = MDC;
192  } else {
193    getMultipleDC()->LexicalDC = DC;
194  }
195}
196
197bool Decl::isInAnonymousNamespace() const {
198  const DeclContext *DC = getDeclContext();
199  do {
200    if (const NamespaceDecl *ND = dyn_cast<NamespaceDecl>(DC))
201      if (ND->isAnonymousNamespace())
202        return true;
203  } while ((DC = DC->getParent()));
204
205  return false;
206}
207
208TranslationUnitDecl *Decl::getTranslationUnitDecl() {
209  if (TranslationUnitDecl *TUD = dyn_cast<TranslationUnitDecl>(this))
210    return TUD;
211
212  DeclContext *DC = getDeclContext();
213  assert(DC && "This decl is not contained in a translation unit!");
214
215  while (!DC->isTranslationUnit()) {
216    DC = DC->getParent();
217    assert(DC && "This decl is not contained in a translation unit!");
218  }
219
220  return cast<TranslationUnitDecl>(DC);
221}
222
223ASTContext &Decl::getASTContext() const {
224  return getTranslationUnitDecl()->getASTContext();
225}
226
227ASTMutationListener *Decl::getASTMutationListener() const {
228  return getASTContext().getASTMutationListener();
229}
230
231bool Decl::isUsed(bool CheckUsedAttr) const {
232  if (Used)
233    return true;
234
235  // Check for used attribute.
236  if (CheckUsedAttr && hasAttr<UsedAttr>())
237    return true;
238
239  // Check redeclarations for used attribute.
240  for (redecl_iterator I = redecls_begin(), E = redecls_end(); I != E; ++I) {
241    if ((CheckUsedAttr && I->hasAttr<UsedAttr>()) || I->Used)
242      return true;
243  }
244
245  return false;
246}
247
248bool Decl::isReferenced() const {
249  if (Referenced)
250    return true;
251
252  // Check redeclarations.
253  for (redecl_iterator I = redecls_begin(), E = redecls_end(); I != E; ++I)
254    if (I->Referenced)
255      return true;
256
257  return false;
258}
259
260/// \brief Determine the availability of the given declaration based on
261/// the target platform.
262///
263/// When it returns an availability result other than \c AR_Available,
264/// if the \p Message parameter is non-NULL, it will be set to a
265/// string describing why the entity is unavailable.
266///
267/// FIXME: Make these strings localizable, since they end up in
268/// diagnostics.
269static AvailabilityResult CheckAvailability(ASTContext &Context,
270                                            const AvailabilityAttr *A,
271                                            std::string *Message) {
272  StringRef TargetPlatform = Context.getTargetInfo().getPlatformName();
273  StringRef PrettyPlatformName
274    = AvailabilityAttr::getPrettyPlatformName(TargetPlatform);
275  if (PrettyPlatformName.empty())
276    PrettyPlatformName = TargetPlatform;
277
278  VersionTuple TargetMinVersion = Context.getTargetInfo().getPlatformMinVersion();
279  if (TargetMinVersion.empty())
280    return AR_Available;
281
282  // Match the platform name.
283  if (A->getPlatform()->getName() != TargetPlatform)
284    return AR_Available;
285
286  // Make sure that this declaration has not been marked 'unavailable'.
287  if (A->getUnavailable()) {
288    if (Message) {
289      Message->clear();
290      llvm::raw_string_ostream Out(*Message);
291      Out << "not available on " << PrettyPlatformName;
292    }
293
294    return AR_Unavailable;
295  }
296
297  // Make sure that this declaration has already been introduced.
298  if (!A->getIntroduced().empty() &&
299      TargetMinVersion < A->getIntroduced()) {
300    if (Message) {
301      Message->clear();
302      llvm::raw_string_ostream Out(*Message);
303      Out << "introduced in " << PrettyPlatformName << ' '
304          << A->getIntroduced();
305    }
306
307    return AR_NotYetIntroduced;
308  }
309
310  // Make sure that this declaration hasn't been obsoleted.
311  if (!A->getObsoleted().empty() && TargetMinVersion >= A->getObsoleted()) {
312    if (Message) {
313      Message->clear();
314      llvm::raw_string_ostream Out(*Message);
315      Out << "obsoleted in " << PrettyPlatformName << ' '
316          << A->getObsoleted();
317    }
318
319    return AR_Unavailable;
320  }
321
322  // Make sure that this declaration hasn't been deprecated.
323  if (!A->getDeprecated().empty() && TargetMinVersion >= A->getDeprecated()) {
324    if (Message) {
325      Message->clear();
326      llvm::raw_string_ostream Out(*Message);
327      Out << "first deprecated in " << PrettyPlatformName << ' '
328          << A->getDeprecated();
329    }
330
331    return AR_Deprecated;
332  }
333
334  return AR_Available;
335}
336
337AvailabilityResult Decl::getAvailability(std::string *Message) const {
338  AvailabilityResult Result = AR_Available;
339  std::string ResultMessage;
340
341  for (attr_iterator A = attr_begin(), AEnd = attr_end(); A != AEnd; ++A) {
342    if (DeprecatedAttr *Deprecated = dyn_cast<DeprecatedAttr>(*A)) {
343      if (Result >= AR_Deprecated)
344        continue;
345
346      if (Message)
347        ResultMessage = Deprecated->getMessage();
348
349      Result = AR_Deprecated;
350      continue;
351    }
352
353    if (UnavailableAttr *Unavailable = dyn_cast<UnavailableAttr>(*A)) {
354      if (Message)
355        *Message = Unavailable->getMessage();
356      return AR_Unavailable;
357    }
358
359    if (AvailabilityAttr *Availability = dyn_cast<AvailabilityAttr>(*A)) {
360      AvailabilityResult AR = CheckAvailability(getASTContext(), Availability,
361                                                Message);
362
363      if (AR == AR_Unavailable)
364        return AR_Unavailable;
365
366      if (AR > Result) {
367        Result = AR;
368        if (Message)
369          ResultMessage.swap(*Message);
370      }
371      continue;
372    }
373  }
374
375  if (Message)
376    Message->swap(ResultMessage);
377  return Result;
378}
379
380bool Decl::canBeWeakImported(bool &IsDefinition) const {
381  IsDefinition = false;
382  if (const VarDecl *Var = dyn_cast<VarDecl>(this)) {
383    if (!Var->hasExternalStorage() || Var->getInit()) {
384      IsDefinition = true;
385      return false;
386    }
387  } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(this)) {
388    if (FD->hasBody()) {
389      IsDefinition = true;
390      return false;
391    }
392  } else if (isa<ObjCPropertyDecl>(this) || isa<ObjCMethodDecl>(this))
393    return false;
394  else if (!(getASTContext().getLangOptions().ObjCNonFragileABI &&
395             isa<ObjCInterfaceDecl>(this)))
396    return false;
397
398  return true;
399}
400
401bool Decl::isWeakImported() const {
402  bool IsDefinition;
403  if (!canBeWeakImported(IsDefinition))
404    return false;
405
406  for (attr_iterator A = attr_begin(), AEnd = attr_end(); A != AEnd; ++A) {
407    if (isa<WeakImportAttr>(*A))
408      return true;
409
410    if (AvailabilityAttr *Availability = dyn_cast<AvailabilityAttr>(*A)) {
411      if (CheckAvailability(getASTContext(), Availability, 0)
412                                                         == AR_NotYetIntroduced)
413        return true;
414    }
415  }
416
417  return false;
418}
419
420unsigned Decl::getIdentifierNamespaceForKind(Kind DeclKind) {
421  switch (DeclKind) {
422    case Function:
423    case CXXMethod:
424    case CXXConstructor:
425    case CXXDestructor:
426    case CXXConversion:
427    case EnumConstant:
428    case Var:
429    case ImplicitParam:
430    case ParmVar:
431    case NonTypeTemplateParm:
432    case ObjCMethod:
433    case ObjCProperty:
434      return IDNS_Ordinary;
435    case Label:
436      return IDNS_Label;
437    case IndirectField:
438      return IDNS_Ordinary | IDNS_Member;
439
440    case ObjCCompatibleAlias:
441    case ObjCInterface:
442      return IDNS_Ordinary | IDNS_Type;
443
444    case Typedef:
445    case TypeAlias:
446    case TypeAliasTemplate:
447    case UnresolvedUsingTypename:
448    case TemplateTypeParm:
449      return IDNS_Ordinary | IDNS_Type;
450
451    case UsingShadow:
452      return 0; // we'll actually overwrite this later
453
454    case UnresolvedUsingValue:
455      return IDNS_Ordinary | IDNS_Using;
456
457    case Using:
458      return IDNS_Using;
459
460    case ObjCProtocol:
461      return IDNS_ObjCProtocol;
462
463    case Field:
464    case ObjCAtDefsField:
465    case ObjCIvar:
466      return IDNS_Member;
467
468    case Record:
469    case CXXRecord:
470    case Enum:
471      return IDNS_Tag | IDNS_Type;
472
473    case Namespace:
474    case NamespaceAlias:
475      return IDNS_Namespace;
476
477    case FunctionTemplate:
478      return IDNS_Ordinary;
479
480    case ClassTemplate:
481    case TemplateTemplateParm:
482      return IDNS_Ordinary | IDNS_Tag | IDNS_Type;
483
484    // Never have names.
485    case Friend:
486    case FriendTemplate:
487    case AccessSpec:
488    case LinkageSpec:
489    case FileScopeAsm:
490    case StaticAssert:
491    case ObjCClass:
492    case ObjCPropertyImpl:
493    case ObjCForwardProtocol:
494    case Block:
495    case TranslationUnit:
496
497    case UsingDirective:
498    case ClassTemplateSpecialization:
499    case ClassTemplatePartialSpecialization:
500    case ClassScopeFunctionSpecialization:
501    case ObjCImplementation:
502    case ObjCCategory:
503    case ObjCCategoryImpl:
504    case Import:
505      // Never looked up by name.
506      return 0;
507  }
508
509  return 0;
510}
511
512void Decl::setAttrs(const AttrVec &attrs) {
513  assert(!HasAttrs && "Decl already contains attrs.");
514
515  AttrVec &AttrBlank = getASTContext().getDeclAttrs(this);
516  assert(AttrBlank.empty() && "HasAttrs was wrong?");
517
518  AttrBlank = attrs;
519  HasAttrs = true;
520}
521
522void Decl::dropAttrs() {
523  if (!HasAttrs) return;
524
525  HasAttrs = false;
526  getASTContext().eraseDeclAttrs(this);
527}
528
529const AttrVec &Decl::getAttrs() const {
530  assert(HasAttrs && "No attrs to get!");
531  return getASTContext().getDeclAttrs(this);
532}
533
534void Decl::swapAttrs(Decl *RHS) {
535  bool HasLHSAttr = this->HasAttrs;
536  bool HasRHSAttr = RHS->HasAttrs;
537
538  // Usually, neither decl has attrs, nothing to do.
539  if (!HasLHSAttr && !HasRHSAttr) return;
540
541  // If 'this' has no attrs, swap the other way.
542  if (!HasLHSAttr)
543    return RHS->swapAttrs(this);
544
545  ASTContext &Context = getASTContext();
546
547  // Handle the case when both decls have attrs.
548  if (HasRHSAttr) {
549    std::swap(Context.getDeclAttrs(this), Context.getDeclAttrs(RHS));
550    return;
551  }
552
553  // Otherwise, LHS has an attr and RHS doesn't.
554  Context.getDeclAttrs(RHS) = Context.getDeclAttrs(this);
555  Context.eraseDeclAttrs(this);
556  this->HasAttrs = false;
557  RHS->HasAttrs = true;
558}
559
560Decl *Decl::castFromDeclContext (const DeclContext *D) {
561  Decl::Kind DK = D->getDeclKind();
562  switch(DK) {
563#define DECL(NAME, BASE)
564#define DECL_CONTEXT(NAME) \
565    case Decl::NAME:       \
566      return static_cast<NAME##Decl*>(const_cast<DeclContext*>(D));
567#define DECL_CONTEXT_BASE(NAME)
568#include "clang/AST/DeclNodes.inc"
569    default:
570#define DECL(NAME, BASE)
571#define DECL_CONTEXT_BASE(NAME)                  \
572      if (DK >= first##NAME && DK <= last##NAME) \
573        return static_cast<NAME##Decl*>(const_cast<DeclContext*>(D));
574#include "clang/AST/DeclNodes.inc"
575      llvm_unreachable("a decl that inherits DeclContext isn't handled");
576  }
577}
578
579DeclContext *Decl::castToDeclContext(const Decl *D) {
580  Decl::Kind DK = D->getKind();
581  switch(DK) {
582#define DECL(NAME, BASE)
583#define DECL_CONTEXT(NAME) \
584    case Decl::NAME:       \
585      return static_cast<NAME##Decl*>(const_cast<Decl*>(D));
586#define DECL_CONTEXT_BASE(NAME)
587#include "clang/AST/DeclNodes.inc"
588    default:
589#define DECL(NAME, BASE)
590#define DECL_CONTEXT_BASE(NAME)                                   \
591      if (DK >= first##NAME && DK <= last##NAME)                  \
592        return static_cast<NAME##Decl*>(const_cast<Decl*>(D));
593#include "clang/AST/DeclNodes.inc"
594      llvm_unreachable("a decl that inherits DeclContext isn't handled");
595  }
596}
597
598SourceLocation Decl::getBodyRBrace() const {
599  // Special handling of FunctionDecl to avoid de-serializing the body from PCH.
600  // FunctionDecl stores EndRangeLoc for this purpose.
601  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(this)) {
602    const FunctionDecl *Definition;
603    if (FD->hasBody(Definition))
604      return Definition->getSourceRange().getEnd();
605    return SourceLocation();
606  }
607
608  if (Stmt *Body = getBody())
609    return Body->getSourceRange().getEnd();
610
611  return SourceLocation();
612}
613
614void Decl::CheckAccessDeclContext() const {
615#ifndef NDEBUG
616  // Suppress this check if any of the following hold:
617  // 1. this is the translation unit (and thus has no parent)
618  // 2. this is a template parameter (and thus doesn't belong to its context)
619  // 3. this is a non-type template parameter
620  // 4. the context is not a record
621  // 5. it's invalid
622  // 6. it's a C++0x static_assert.
623  if (isa<TranslationUnitDecl>(this) ||
624      isa<TemplateTypeParmDecl>(this) ||
625      isa<NonTypeTemplateParmDecl>(this) ||
626      !isa<CXXRecordDecl>(getDeclContext()) ||
627      isInvalidDecl() ||
628      isa<StaticAssertDecl>(this) ||
629      // FIXME: a ParmVarDecl can have ClassTemplateSpecialization
630      // as DeclContext (?).
631      isa<ParmVarDecl>(this) ||
632      // FIXME: a ClassTemplateSpecialization or CXXRecordDecl can have
633      // AS_none as access specifier.
634      isa<CXXRecordDecl>(this) ||
635      isa<ClassScopeFunctionSpecializationDecl>(this))
636    return;
637
638  assert(Access != AS_none &&
639         "Access specifier is AS_none inside a record decl");
640#endif
641}
642
643DeclContext *Decl::getNonClosureContext() {
644  return getDeclContext()->getNonClosureAncestor();
645}
646
647DeclContext *DeclContext::getNonClosureAncestor() {
648  DeclContext *DC = this;
649
650  // This is basically "while (DC->isClosure()) DC = DC->getParent();"
651  // except that it's significantly more efficient to cast to a known
652  // decl type and call getDeclContext() than to call getParent().
653  while (isa<BlockDecl>(DC))
654    DC = cast<BlockDecl>(DC)->getDeclContext();
655
656  assert(!DC->isClosure());
657  return DC;
658}
659
660//===----------------------------------------------------------------------===//
661// DeclContext Implementation
662//===----------------------------------------------------------------------===//
663
664bool DeclContext::classof(const Decl *D) {
665  switch (D->getKind()) {
666#define DECL(NAME, BASE)
667#define DECL_CONTEXT(NAME) case Decl::NAME:
668#define DECL_CONTEXT_BASE(NAME)
669#include "clang/AST/DeclNodes.inc"
670      return true;
671    default:
672#define DECL(NAME, BASE)
673#define DECL_CONTEXT_BASE(NAME)                 \
674      if (D->getKind() >= Decl::first##NAME &&  \
675          D->getKind() <= Decl::last##NAME)     \
676        return true;
677#include "clang/AST/DeclNodes.inc"
678      return false;
679  }
680}
681
682DeclContext::~DeclContext() { }
683
684/// \brief Find the parent context of this context that will be
685/// used for unqualified name lookup.
686///
687/// Generally, the parent lookup context is the semantic context. However, for
688/// a friend function the parent lookup context is the lexical context, which
689/// is the class in which the friend is declared.
690DeclContext *DeclContext::getLookupParent() {
691  // FIXME: Find a better way to identify friends
692  if (isa<FunctionDecl>(this))
693    if (getParent()->getRedeclContext()->isFileContext() &&
694        getLexicalParent()->getRedeclContext()->isRecord())
695      return getLexicalParent();
696
697  return getParent();
698}
699
700bool DeclContext::isInlineNamespace() const {
701  return isNamespace() &&
702         cast<NamespaceDecl>(this)->isInline();
703}
704
705bool DeclContext::isDependentContext() const {
706  if (isFileContext())
707    return false;
708
709  if (isa<ClassTemplatePartialSpecializationDecl>(this))
710    return true;
711
712  if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(this))
713    if (Record->getDescribedClassTemplate())
714      return true;
715
716  if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(this)) {
717    if (Function->getDescribedFunctionTemplate())
718      return true;
719
720    // Friend function declarations are dependent if their *lexical*
721    // context is dependent.
722    if (cast<Decl>(this)->getFriendObjectKind())
723      return getLexicalParent()->isDependentContext();
724  }
725
726  return getParent() && getParent()->isDependentContext();
727}
728
729bool DeclContext::isTransparentContext() const {
730  if (DeclKind == Decl::Enum)
731    return !cast<EnumDecl>(this)->isScoped();
732  else if (DeclKind == Decl::LinkageSpec)
733    return true;
734
735  return false;
736}
737
738bool DeclContext::isExternCContext() const {
739  const DeclContext *DC = this;
740  while (DC->DeclKind != Decl::TranslationUnit) {
741    if (DC->DeclKind == Decl::LinkageSpec)
742      return cast<LinkageSpecDecl>(DC)->getLanguage()
743        == LinkageSpecDecl::lang_c;
744    DC = DC->getParent();
745  }
746  return false;
747}
748
749bool DeclContext::Encloses(const DeclContext *DC) const {
750  if (getPrimaryContext() != this)
751    return getPrimaryContext()->Encloses(DC);
752
753  for (; DC; DC = DC->getParent())
754    if (DC->getPrimaryContext() == this)
755      return true;
756  return false;
757}
758
759DeclContext *DeclContext::getPrimaryContext() {
760  switch (DeclKind) {
761  case Decl::TranslationUnit:
762  case Decl::LinkageSpec:
763  case Decl::Block:
764    // There is only one DeclContext for these entities.
765    return this;
766
767  case Decl::Namespace:
768    // The original namespace is our primary context.
769    return static_cast<NamespaceDecl*>(this)->getOriginalNamespace();
770
771  case Decl::ObjCMethod:
772    return this;
773
774  case Decl::ObjCInterface:
775  case Decl::ObjCProtocol:
776  case Decl::ObjCCategory:
777    // FIXME: Can Objective-C interfaces be forward-declared?
778    return this;
779
780  case Decl::ObjCImplementation:
781  case Decl::ObjCCategoryImpl:
782    return this;
783
784  default:
785    if (DeclKind >= Decl::firstTag && DeclKind <= Decl::lastTag) {
786      // If this is a tag type that has a definition or is currently
787      // being defined, that definition is our primary context.
788      TagDecl *Tag = cast<TagDecl>(this);
789      assert(isa<TagType>(Tag->TypeForDecl) ||
790             isa<InjectedClassNameType>(Tag->TypeForDecl));
791
792      if (TagDecl *Def = Tag->getDefinition())
793        return Def;
794
795      if (!isa<InjectedClassNameType>(Tag->TypeForDecl)) {
796        const TagType *TagTy = cast<TagType>(Tag->TypeForDecl);
797        if (TagTy->isBeingDefined())
798          // FIXME: is it necessarily being defined in the decl
799          // that owns the type?
800          return TagTy->getDecl();
801      }
802
803      return Tag;
804    }
805
806    assert(DeclKind >= Decl::firstFunction && DeclKind <= Decl::lastFunction &&
807          "Unknown DeclContext kind");
808    return this;
809  }
810}
811
812DeclContext *DeclContext::getNextContext() {
813  switch (DeclKind) {
814  case Decl::Namespace:
815    // Return the next namespace
816    return static_cast<NamespaceDecl*>(this)->getNextNamespace();
817
818  default:
819    return 0;
820  }
821}
822
823std::pair<Decl *, Decl *>
824DeclContext::BuildDeclChain(const SmallVectorImpl<Decl*> &Decls,
825                            bool FieldsAlreadyLoaded) {
826  // Build up a chain of declarations via the Decl::NextDeclInContext field.
827  Decl *FirstNewDecl = 0;
828  Decl *PrevDecl = 0;
829  for (unsigned I = 0, N = Decls.size(); I != N; ++I) {
830    if (FieldsAlreadyLoaded && isa<FieldDecl>(Decls[I]))
831      continue;
832
833    Decl *D = Decls[I];
834    if (PrevDecl)
835      PrevDecl->NextDeclInContext = D;
836    else
837      FirstNewDecl = D;
838
839    PrevDecl = D;
840  }
841
842  return std::make_pair(FirstNewDecl, PrevDecl);
843}
844
845/// \brief Load the declarations within this lexical storage from an
846/// external source.
847void
848DeclContext::LoadLexicalDeclsFromExternalStorage() const {
849  ExternalASTSource *Source = getParentASTContext().getExternalSource();
850  assert(hasExternalLexicalStorage() && Source && "No external storage?");
851
852  // Notify that we have a DeclContext that is initializing.
853  ExternalASTSource::Deserializing ADeclContext(Source);
854
855  // Load the external declarations, if any.
856  SmallVector<Decl*, 64> Decls;
857  ExternalLexicalStorage = false;
858  switch (Source->FindExternalLexicalDecls(this, Decls)) {
859  case ELR_Success:
860    break;
861
862  case ELR_Failure:
863  case ELR_AlreadyLoaded:
864    return;
865  }
866
867  if (Decls.empty())
868    return;
869
870  // We may have already loaded just the fields of this record, in which case
871  // we need to ignore them.
872  bool FieldsAlreadyLoaded = false;
873  if (const RecordDecl *RD = dyn_cast<RecordDecl>(this))
874    FieldsAlreadyLoaded = RD->LoadedFieldsFromExternalStorage;
875
876  // Splice the newly-read declarations into the beginning of the list
877  // of declarations.
878  Decl *ExternalFirst, *ExternalLast;
879  llvm::tie(ExternalFirst, ExternalLast) = BuildDeclChain(Decls,
880                                                          FieldsAlreadyLoaded);
881  ExternalLast->NextDeclInContext = FirstDecl;
882  FirstDecl = ExternalFirst;
883  if (!LastDecl)
884    LastDecl = ExternalLast;
885}
886
887DeclContext::lookup_result
888ExternalASTSource::SetNoExternalVisibleDeclsForName(const DeclContext *DC,
889                                                    DeclarationName Name) {
890  ASTContext &Context = DC->getParentASTContext();
891  StoredDeclsMap *Map;
892  if (!(Map = DC->LookupPtr))
893    Map = DC->CreateStoredDeclsMap(Context);
894
895  StoredDeclsList &List = (*Map)[Name];
896  assert(List.isNull());
897  (void) List;
898
899  return DeclContext::lookup_result();
900}
901
902DeclContext::lookup_result
903ExternalASTSource::SetExternalVisibleDeclsForName(const DeclContext *DC,
904                                                  DeclarationName Name,
905                                                  ArrayRef<NamedDecl*> Decls) {
906  ASTContext &Context = DC->getParentASTContext();;
907
908  StoredDeclsMap *Map;
909  if (!(Map = DC->LookupPtr))
910    Map = DC->CreateStoredDeclsMap(Context);
911
912  StoredDeclsList &List = (*Map)[Name];
913  for (ArrayRef<NamedDecl*>::iterator
914         I = Decls.begin(), E = Decls.end(); I != E; ++I) {
915    if (List.isNull())
916      List.setOnlyValue(*I);
917    else
918      List.AddSubsequentDecl(*I);
919  }
920
921  return List.getLookupResult();
922}
923
924DeclContext::decl_iterator DeclContext::noload_decls_begin() const {
925  return decl_iterator(FirstDecl);
926}
927
928DeclContext::decl_iterator DeclContext::noload_decls_end() const {
929  return decl_iterator();
930}
931
932DeclContext::decl_iterator DeclContext::decls_begin() const {
933  if (hasExternalLexicalStorage())
934    LoadLexicalDeclsFromExternalStorage();
935
936  return decl_iterator(FirstDecl);
937}
938
939DeclContext::decl_iterator DeclContext::decls_end() const {
940  if (hasExternalLexicalStorage())
941    LoadLexicalDeclsFromExternalStorage();
942
943  return decl_iterator();
944}
945
946bool DeclContext::decls_empty() const {
947  if (hasExternalLexicalStorage())
948    LoadLexicalDeclsFromExternalStorage();
949
950  return !FirstDecl;
951}
952
953void DeclContext::removeDecl(Decl *D) {
954  assert(D->getLexicalDeclContext() == this &&
955         "decl being removed from non-lexical context");
956  assert((D->NextDeclInContext || D == LastDecl) &&
957         "decl is not in decls list");
958
959  // Remove D from the decl chain.  This is O(n) but hopefully rare.
960  if (D == FirstDecl) {
961    if (D == LastDecl)
962      FirstDecl = LastDecl = 0;
963    else
964      FirstDecl = D->NextDeclInContext;
965  } else {
966    for (Decl *I = FirstDecl; true; I = I->NextDeclInContext) {
967      assert(I && "decl not found in linked list");
968      if (I->NextDeclInContext == D) {
969        I->NextDeclInContext = D->NextDeclInContext;
970        if (D == LastDecl) LastDecl = I;
971        break;
972      }
973    }
974  }
975
976  // Mark that D is no longer in the decl chain.
977  D->NextDeclInContext = 0;
978
979  // Remove D from the lookup table if necessary.
980  if (isa<NamedDecl>(D)) {
981    NamedDecl *ND = cast<NamedDecl>(D);
982
983    // Remove only decls that have a name
984    if (!ND->getDeclName()) return;
985
986    StoredDeclsMap *Map = getPrimaryContext()->LookupPtr;
987    if (!Map) return;
988
989    StoredDeclsMap::iterator Pos = Map->find(ND->getDeclName());
990    assert(Pos != Map->end() && "no lookup entry for decl");
991    if (Pos->second.getAsVector() || Pos->second.getAsDecl() == ND)
992      Pos->second.remove(ND);
993  }
994}
995
996void DeclContext::addHiddenDecl(Decl *D) {
997  assert(D->getLexicalDeclContext() == this &&
998         "Decl inserted into wrong lexical context");
999  assert(!D->getNextDeclInContext() && D != LastDecl &&
1000         "Decl already inserted into a DeclContext");
1001
1002  if (FirstDecl) {
1003    LastDecl->NextDeclInContext = D;
1004    LastDecl = D;
1005  } else {
1006    FirstDecl = LastDecl = D;
1007  }
1008
1009  // Notify a C++ record declaration that we've added a member, so it can
1010  // update it's class-specific state.
1011  if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(this))
1012    Record->addedMember(D);
1013
1014  // If this is a newly-created (not de-serialized) import declaration, wire
1015  // it in to the list of local import declarations.
1016  if (!D->isFromASTFile()) {
1017    if (ImportDecl *Import = dyn_cast<ImportDecl>(D))
1018      D->getASTContext().addedLocalImportDecl(Import);
1019  }
1020}
1021
1022void DeclContext::addDecl(Decl *D) {
1023  addHiddenDecl(D);
1024
1025  if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
1026    ND->getDeclContext()->makeDeclVisibleInContext(ND);
1027}
1028
1029void DeclContext::addDeclInternal(Decl *D) {
1030  addHiddenDecl(D);
1031
1032  if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
1033    ND->getDeclContext()->makeDeclVisibleInContextInternal(ND);
1034}
1035
1036/// buildLookup - Build the lookup data structure with all of the
1037/// declarations in DCtx (and any other contexts linked to it or
1038/// transparent contexts nested within it).
1039void DeclContext::buildLookup(DeclContext *DCtx) {
1040  for (; DCtx; DCtx = DCtx->getNextContext()) {
1041    for (decl_iterator D = DCtx->decls_begin(),
1042                    DEnd = DCtx->decls_end();
1043         D != DEnd; ++D) {
1044      // Insert this declaration into the lookup structure, but only
1045      // if it's semantically in its decl context.  During non-lazy
1046      // lookup building, this is implicitly enforced by addDecl.
1047      if (NamedDecl *ND = dyn_cast<NamedDecl>(*D))
1048        if (D->getDeclContext() == DCtx)
1049          makeDeclVisibleInContextImpl(ND, false);
1050
1051      // Insert any forward-declared Objective-C interface into the lookup
1052      // data structure.
1053      if (ObjCClassDecl *Class = dyn_cast<ObjCClassDecl>(*D))
1054        makeDeclVisibleInContextImpl(Class->getForwardInterfaceDecl(), false);
1055
1056      // If this declaration is itself a transparent declaration context or
1057      // inline namespace, add its members (recursively).
1058      if (DeclContext *InnerCtx = dyn_cast<DeclContext>(*D))
1059        if (InnerCtx->isTransparentContext() || InnerCtx->isInlineNamespace())
1060          buildLookup(InnerCtx->getPrimaryContext());
1061    }
1062  }
1063}
1064
1065DeclContext::lookup_result
1066DeclContext::lookup(DeclarationName Name) {
1067  DeclContext *PrimaryContext = getPrimaryContext();
1068  if (PrimaryContext != this)
1069    return PrimaryContext->lookup(Name);
1070
1071  if (hasExternalVisibleStorage()) {
1072    // Check to see if we've already cached the lookup results.
1073    if (LookupPtr) {
1074      StoredDeclsMap::iterator I = LookupPtr->find(Name);
1075      if (I != LookupPtr->end())
1076        return I->second.getLookupResult();
1077    }
1078
1079    ExternalASTSource *Source = getParentASTContext().getExternalSource();
1080    return Source->FindExternalVisibleDeclsByName(this, Name);
1081  }
1082
1083  /// If there is no lookup data structure, build one now by walking
1084  /// all of the linked DeclContexts (in declaration order!) and
1085  /// inserting their values.
1086  if (!LookupPtr) {
1087    buildLookup(this);
1088
1089    if (!LookupPtr)
1090      return lookup_result(lookup_iterator(0), lookup_iterator(0));
1091  }
1092
1093  StoredDeclsMap::iterator Pos = LookupPtr->find(Name);
1094  if (Pos == LookupPtr->end())
1095    return lookup_result(lookup_iterator(0), lookup_iterator(0));
1096  return Pos->second.getLookupResult();
1097}
1098
1099DeclContext::lookup_const_result
1100DeclContext::lookup(DeclarationName Name) const {
1101  return const_cast<DeclContext*>(this)->lookup(Name);
1102}
1103
1104void DeclContext::localUncachedLookup(DeclarationName Name,
1105                                  llvm::SmallVectorImpl<NamedDecl *> &Results) {
1106  Results.clear();
1107
1108  // If there's no external storage, just perform a normal lookup and copy
1109  // the results.
1110  if (!hasExternalVisibleStorage() && !hasExternalLexicalStorage()) {
1111    lookup_result LookupResults = lookup(Name);
1112    Results.insert(Results.end(), LookupResults.first, LookupResults.second);
1113    return;
1114  }
1115
1116  // If we have a lookup table, check there first. Maybe we'll get lucky.
1117  if (LookupPtr) {
1118    StoredDeclsMap::iterator Pos = LookupPtr->find(Name);
1119    if (Pos != LookupPtr->end()) {
1120      Results.insert(Results.end(),
1121                     Pos->second.getLookupResult().first,
1122                     Pos->second.getLookupResult().second);
1123      return;
1124    }
1125  }
1126
1127  // Slow case: grovel through the declarations in our chain looking for
1128  // matches.
1129  for (Decl *D = FirstDecl; D; D = D->getNextDeclInContext()) {
1130    if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
1131      if (ND->getDeclName() == Name)
1132        Results.push_back(ND);
1133  }
1134}
1135
1136DeclContext *DeclContext::getRedeclContext() {
1137  DeclContext *Ctx = this;
1138  // Skip through transparent contexts.
1139  while (Ctx->isTransparentContext())
1140    Ctx = Ctx->getParent();
1141  return Ctx;
1142}
1143
1144DeclContext *DeclContext::getEnclosingNamespaceContext() {
1145  DeclContext *Ctx = this;
1146  // Skip through non-namespace, non-translation-unit contexts.
1147  while (!Ctx->isFileContext())
1148    Ctx = Ctx->getParent();
1149  return Ctx->getPrimaryContext();
1150}
1151
1152bool DeclContext::InEnclosingNamespaceSetOf(const DeclContext *O) const {
1153  // For non-file contexts, this is equivalent to Equals.
1154  if (!isFileContext())
1155    return O->Equals(this);
1156
1157  do {
1158    if (O->Equals(this))
1159      return true;
1160
1161    const NamespaceDecl *NS = dyn_cast<NamespaceDecl>(O);
1162    if (!NS || !NS->isInline())
1163      break;
1164    O = NS->getParent();
1165  } while (O);
1166
1167  return false;
1168}
1169
1170void DeclContext::makeDeclVisibleInContext(NamedDecl *D, bool Recoverable)
1171{
1172    makeDeclVisibleInContextWithFlags(D, false, Recoverable);
1173}
1174
1175void DeclContext::makeDeclVisibleInContextInternal(NamedDecl *D, bool Recoverable)
1176{
1177    makeDeclVisibleInContextWithFlags(D, true, Recoverable);
1178}
1179
1180void DeclContext::makeDeclVisibleInContextWithFlags(NamedDecl *D, bool Internal, bool Recoverable) {
1181  // FIXME: This feels like a hack. Should DeclarationName support
1182  // template-ids, or is there a better way to keep specializations
1183  // from being visible?
1184  if (isa<ClassTemplateSpecializationDecl>(D) || D->isTemplateParameter())
1185    return;
1186  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
1187    if (FD->isFunctionTemplateSpecialization())
1188      return;
1189
1190  DeclContext *PrimaryContext = getPrimaryContext();
1191  if (PrimaryContext != this) {
1192    PrimaryContext->makeDeclVisibleInContextWithFlags(D, Internal, Recoverable);
1193    return;
1194  }
1195
1196  // If we already have a lookup data structure, perform the insertion
1197  // into it. If we haven't deserialized externally stored decls, deserialize
1198  // them so we can add the decl. Otherwise, be lazy and don't build that
1199  // structure until someone asks for it.
1200  if (LookupPtr || !Recoverable || hasExternalVisibleStorage())
1201    makeDeclVisibleInContextImpl(D, Internal);
1202
1203  // If we are a transparent context or inline namespace, insert into our
1204  // parent context, too. This operation is recursive.
1205  if (isTransparentContext() || isInlineNamespace())
1206    getParent()->makeDeclVisibleInContextWithFlags(D, Internal, Recoverable);
1207
1208  Decl *DCAsDecl = cast<Decl>(this);
1209  // Notify that a decl was made visible unless it's a Tag being defined.
1210  if (!(isa<TagDecl>(DCAsDecl) && cast<TagDecl>(DCAsDecl)->isBeingDefined()))
1211    if (ASTMutationListener *L = DCAsDecl->getASTMutationListener())
1212      L->AddedVisibleDecl(this, D);
1213}
1214
1215void DeclContext::makeDeclVisibleInContextImpl(NamedDecl *D, bool Internal) {
1216  // Skip unnamed declarations.
1217  if (!D->getDeclName())
1218    return;
1219
1220  // Skip entities that can't be found by name lookup into a particular
1221  // context.
1222  if ((D->getIdentifierNamespace() == 0 && !isa<UsingDirectiveDecl>(D)) ||
1223      D->isTemplateParameter())
1224    return;
1225
1226  ASTContext *C = 0;
1227  if (!LookupPtr) {
1228    C = &getParentASTContext();
1229    CreateStoredDeclsMap(*C);
1230  }
1231
1232  // If there is an external AST source, load any declarations it knows about
1233  // with this declaration's name.
1234  // If the lookup table contains an entry about this name it means that we
1235  // have already checked the external source.
1236  if (!Internal)
1237    if (ExternalASTSource *Source = getParentASTContext().getExternalSource())
1238      if (hasExternalVisibleStorage() &&
1239          LookupPtr->find(D->getDeclName()) == LookupPtr->end())
1240        Source->FindExternalVisibleDeclsByName(this, D->getDeclName());
1241
1242  // Insert this declaration into the map.
1243  StoredDeclsList &DeclNameEntries = (*LookupPtr)[D->getDeclName()];
1244  if (DeclNameEntries.isNull()) {
1245    DeclNameEntries.setOnlyValue(D);
1246    return;
1247  }
1248
1249  // If it is possible that this is a redeclaration, check to see if there is
1250  // already a decl for which declarationReplaces returns true.  If there is
1251  // one, just replace it and return.
1252  if (DeclNameEntries.HandleRedeclaration(D))
1253    return;
1254
1255  // Put this declaration into the appropriate slot.
1256  DeclNameEntries.AddSubsequentDecl(D);
1257}
1258
1259/// Returns iterator range [First, Last) of UsingDirectiveDecls stored within
1260/// this context.
1261DeclContext::udir_iterator_range
1262DeclContext::getUsingDirectives() const {
1263  lookup_const_result Result = lookup(UsingDirectiveDecl::getName());
1264  return udir_iterator_range(reinterpret_cast<udir_iterator>(Result.first),
1265                             reinterpret_cast<udir_iterator>(Result.second));
1266}
1267
1268//===----------------------------------------------------------------------===//
1269// Creation and Destruction of StoredDeclsMaps.                               //
1270//===----------------------------------------------------------------------===//
1271
1272StoredDeclsMap *DeclContext::CreateStoredDeclsMap(ASTContext &C) const {
1273  assert(!LookupPtr && "context already has a decls map");
1274  assert(getPrimaryContext() == this &&
1275         "creating decls map on non-primary context");
1276
1277  StoredDeclsMap *M;
1278  bool Dependent = isDependentContext();
1279  if (Dependent)
1280    M = new DependentStoredDeclsMap();
1281  else
1282    M = new StoredDeclsMap();
1283  M->Previous = C.LastSDM;
1284  C.LastSDM = llvm::PointerIntPair<StoredDeclsMap*,1>(M, Dependent);
1285  LookupPtr = M;
1286  return M;
1287}
1288
1289void ASTContext::ReleaseDeclContextMaps() {
1290  // It's okay to delete DependentStoredDeclsMaps via a StoredDeclsMap
1291  // pointer because the subclass doesn't add anything that needs to
1292  // be deleted.
1293  StoredDeclsMap::DestroyAll(LastSDM.getPointer(), LastSDM.getInt());
1294}
1295
1296void StoredDeclsMap::DestroyAll(StoredDeclsMap *Map, bool Dependent) {
1297  while (Map) {
1298    // Advance the iteration before we invalidate memory.
1299    llvm::PointerIntPair<StoredDeclsMap*,1> Next = Map->Previous;
1300
1301    if (Dependent)
1302      delete static_cast<DependentStoredDeclsMap*>(Map);
1303    else
1304      delete Map;
1305
1306    Map = Next.getPointer();
1307    Dependent = Next.getInt();
1308  }
1309}
1310
1311DependentDiagnostic *DependentDiagnostic::Create(ASTContext &C,
1312                                                 DeclContext *Parent,
1313                                           const PartialDiagnostic &PDiag) {
1314  assert(Parent->isDependentContext()
1315         && "cannot iterate dependent diagnostics of non-dependent context");
1316  Parent = Parent->getPrimaryContext();
1317  if (!Parent->LookupPtr)
1318    Parent->CreateStoredDeclsMap(C);
1319
1320  DependentStoredDeclsMap *Map
1321    = static_cast<DependentStoredDeclsMap*>(Parent->LookupPtr);
1322
1323  // Allocate the copy of the PartialDiagnostic via the ASTContext's
1324  // BumpPtrAllocator, rather than the ASTContext itself.
1325  PartialDiagnostic::Storage *DiagStorage = 0;
1326  if (PDiag.hasStorage())
1327    DiagStorage = new (C) PartialDiagnostic::Storage;
1328
1329  DependentDiagnostic *DD = new (C) DependentDiagnostic(PDiag, DiagStorage);
1330
1331  // TODO: Maybe we shouldn't reverse the order during insertion.
1332  DD->NextDiagnostic = Map->FirstDiagnostic;
1333  Map->FirstDiagnostic = DD;
1334
1335  return DD;
1336}
1337