ASTContext.cpp revision 55d23c925b058be29b792008ddb7d68f6c4fa9a0 
1//===--- ASTContext.cpp - Context to hold long-lived AST nodes ------------===//
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 ASTContext interface.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/AST/ASTContext.h"
15#include "clang/AST/CharUnits.h"
16#include "clang/AST/DeclCXX.h"
17#include "clang/AST/DeclObjC.h"
18#include "clang/AST/DeclTemplate.h"
19#include "clang/AST/TypeLoc.h"
20#include "clang/AST/Expr.h"
21#include "clang/AST/ExprCXX.h"
22#include "clang/AST/ExternalASTSource.h"
23#include "clang/AST/ASTMutationListener.h"
24#include "clang/AST/RecordLayout.h"
25#include "clang/AST/Mangle.h"
26#include "clang/Basic/Builtins.h"
27#include "clang/Basic/PartialDiagnostic.h"
28#include "clang/Basic/SourceManager.h"
29#include "clang/Basic/TargetInfo.h"
30#include "llvm/ADT/SmallString.h"
31#include "llvm/ADT/StringExtras.h"
32#include "llvm/Support/MathExtras.h"
33#include "llvm/Support/raw_ostream.h"
34#include "llvm/Support/Capacity.h"
35#include "CXXABI.h"
36#include <map>
37
38using namespace clang;
39
40unsigned ASTContext::NumImplicitDefaultConstructors;
41unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
42unsigned ASTContext::NumImplicitCopyConstructors;
43unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
44unsigned ASTContext::NumImplicitMoveConstructors;
45unsigned ASTContext::NumImplicitMoveConstructorsDeclared;
46unsigned ASTContext::NumImplicitCopyAssignmentOperators;
47unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
48unsigned ASTContext::NumImplicitMoveAssignmentOperators;
49unsigned ASTContext::NumImplicitMoveAssignmentOperatorsDeclared;
50unsigned ASTContext::NumImplicitDestructors;
51unsigned ASTContext::NumImplicitDestructorsDeclared;
52
53enum FloatingRank {
54  HalfRank, FloatRank, DoubleRank, LongDoubleRank
55};
56
57void
58ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
59                                               TemplateTemplateParmDecl *Parm) {
60  ID.AddInteger(Parm->getDepth());
61  ID.AddInteger(Parm->getPosition());
62  ID.AddBoolean(Parm->isParameterPack());
63
64  TemplateParameterList *Params = Parm->getTemplateParameters();
65  ID.AddInteger(Params->size());
66  for (TemplateParameterList::const_iterator P = Params->begin(),
67                                          PEnd = Params->end();
68       P != PEnd; ++P) {
69    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
70      ID.AddInteger(0);
71      ID.AddBoolean(TTP->isParameterPack());
72      continue;
73    }
74
75    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
76      ID.AddInteger(1);
77      ID.AddBoolean(NTTP->isParameterPack());
78      ID.AddPointer(NTTP->getType().getAsOpaquePtr());
79      if (NTTP->isExpandedParameterPack()) {
80        ID.AddBoolean(true);
81        ID.AddInteger(NTTP->getNumExpansionTypes());
82        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I)
83          ID.AddPointer(NTTP->getExpansionType(I).getAsOpaquePtr());
84      } else
85        ID.AddBoolean(false);
86      continue;
87    }
88
89    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
90    ID.AddInteger(2);
91    Profile(ID, TTP);
92  }
93}
94
95TemplateTemplateParmDecl *
96ASTContext::getCanonicalTemplateTemplateParmDecl(
97                                          TemplateTemplateParmDecl *TTP) const {
98  // Check if we already have a canonical template template parameter.
99  llvm::FoldingSetNodeID ID;
100  CanonicalTemplateTemplateParm::Profile(ID, TTP);
101  void *InsertPos = 0;
102  CanonicalTemplateTemplateParm *Canonical
103    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
104  if (Canonical)
105    return Canonical->getParam();
106
107  // Build a canonical template parameter list.
108  TemplateParameterList *Params = TTP->getTemplateParameters();
109  SmallVector<NamedDecl *, 4> CanonParams;
110  CanonParams.reserve(Params->size());
111  for (TemplateParameterList::const_iterator P = Params->begin(),
112                                          PEnd = Params->end();
113       P != PEnd; ++P) {
114    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
115      CanonParams.push_back(
116                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
117                                               SourceLocation(),
118                                               SourceLocation(),
119                                               TTP->getDepth(),
120                                               TTP->getIndex(), 0, false,
121                                               TTP->isParameterPack()));
122    else if (NonTypeTemplateParmDecl *NTTP
123             = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
124      QualType T = getCanonicalType(NTTP->getType());
125      TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
126      NonTypeTemplateParmDecl *Param;
127      if (NTTP->isExpandedParameterPack()) {
128        SmallVector<QualType, 2> ExpandedTypes;
129        SmallVector<TypeSourceInfo *, 2> ExpandedTInfos;
130        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
131          ExpandedTypes.push_back(getCanonicalType(NTTP->getExpansionType(I)));
132          ExpandedTInfos.push_back(
133                                getTrivialTypeSourceInfo(ExpandedTypes.back()));
134        }
135
136        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
137                                                SourceLocation(),
138                                                SourceLocation(),
139                                                NTTP->getDepth(),
140                                                NTTP->getPosition(), 0,
141                                                T,
142                                                TInfo,
143                                                ExpandedTypes.data(),
144                                                ExpandedTypes.size(),
145                                                ExpandedTInfos.data());
146      } else {
147        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
148                                                SourceLocation(),
149                                                SourceLocation(),
150                                                NTTP->getDepth(),
151                                                NTTP->getPosition(), 0,
152                                                T,
153                                                NTTP->isParameterPack(),
154                                                TInfo);
155      }
156      CanonParams.push_back(Param);
157
158    } else
159      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
160                                           cast<TemplateTemplateParmDecl>(*P)));
161  }
162
163  TemplateTemplateParmDecl *CanonTTP
164    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
165                                       SourceLocation(), TTP->getDepth(),
166                                       TTP->getPosition(),
167                                       TTP->isParameterPack(),
168                                       0,
169                         TemplateParameterList::Create(*this, SourceLocation(),
170                                                       SourceLocation(),
171                                                       CanonParams.data(),
172                                                       CanonParams.size(),
173                                                       SourceLocation()));
174
175  // Get the new insert position for the node we care about.
176  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
177  assert(Canonical == 0 && "Shouldn't be in the map!");
178  (void)Canonical;
179
180  // Create the canonical template template parameter entry.
181  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
182  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
183  return CanonTTP;
184}
185
186CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
187  if (!LangOpts.CPlusPlus) return 0;
188
189  switch (T.getCXXABI()) {
190  case CXXABI_ARM:
191    return CreateARMCXXABI(*this);
192  case CXXABI_Itanium:
193    return CreateItaniumCXXABI(*this);
194  case CXXABI_Microsoft:
195    return CreateMicrosoftCXXABI(*this);
196  }
197  llvm_unreachable("Invalid CXXABI type!");
198}
199
200static const LangAS::Map *getAddressSpaceMap(const TargetInfo &T,
201                                             const LangOptions &LOpts) {
202  if (LOpts.FakeAddressSpaceMap) {
203    // The fake address space map must have a distinct entry for each
204    // language-specific address space.
205    static const unsigned FakeAddrSpaceMap[] = {
206      1, // opencl_global
207      2, // opencl_local
208      3  // opencl_constant
209    };
210    return &FakeAddrSpaceMap;
211  } else {
212    return &T.getAddressSpaceMap();
213  }
214}
215
216ASTContext::ASTContext(LangOptions& LOpts, SourceManager &SM,
217                       const TargetInfo *t,
218                       IdentifierTable &idents, SelectorTable &sels,
219                       Builtin::Context &builtins,
220                       unsigned size_reserve,
221                       bool DelayInitialization)
222  : FunctionProtoTypes(this_()),
223    TemplateSpecializationTypes(this_()),
224    DependentTemplateSpecializationTypes(this_()),
225    SubstTemplateTemplateParmPacks(this_()),
226    GlobalNestedNameSpecifier(0),
227    Int128Decl(0), UInt128Decl(0),
228    ObjCIdDecl(0), ObjCSelDecl(0), ObjCClassDecl(0), ObjCProtocolClassDecl(0),
229    CFConstantStringTypeDecl(0), ObjCInstanceTypeDecl(0),
230    FILEDecl(0),
231    jmp_bufDecl(0), sigjmp_bufDecl(0), ucontext_tDecl(0),
232    BlockDescriptorType(0), BlockDescriptorExtendedType(0),
233    cudaConfigureCallDecl(0),
234    NullTypeSourceInfo(QualType()),
235    FirstLocalImport(), LastLocalImport(),
236    SourceMgr(SM), LangOpts(LOpts),
237    AddrSpaceMap(0), Target(t), PrintingPolicy(LOpts),
238    Idents(idents), Selectors(sels),
239    BuiltinInfo(builtins),
240    DeclarationNames(*this),
241    ExternalSource(0), Listener(0),
242    LastSDM(0, 0),
243    UniqueBlockByRefTypeID(0)
244{
245  // Create a new allocator for partial diagnostics.
246  DiagAllocator = new (BumpAlloc) PartialDiagnosticStorageAllocator;
247
248  if (size_reserve > 0) Types.reserve(size_reserve);
249  TUDecl = TranslationUnitDecl::Create(*this);
250
251  if (!DelayInitialization) {
252    assert(t && "No target supplied for ASTContext initialization");
253    InitBuiltinTypes(*t);
254  }
255}
256
257ASTContext::~ASTContext() {
258  // Release the DenseMaps associated with DeclContext objects.
259  // FIXME: Is this the ideal solution?
260  ReleaseDeclContextMaps();
261
262  // Call all of the deallocation functions.
263  for (unsigned I = 0, N = Deallocations.size(); I != N; ++I)
264    Deallocations[I].first(Deallocations[I].second);
265
266  // Release all of the memory associated with overridden C++ methods.
267  for (llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::iterator
268         OM = OverriddenMethods.begin(), OMEnd = OverriddenMethods.end();
269       OM != OMEnd; ++OM)
270    OM->second.Destroy();
271
272  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
273  // because they can contain DenseMaps.
274  for (llvm::DenseMap<const ObjCContainerDecl*,
275       const ASTRecordLayout*>::iterator
276       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
277    // Increment in loop to prevent using deallocated memory.
278    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
279      R->Destroy(*this);
280
281  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
282       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
283    // Increment in loop to prevent using deallocated memory.
284    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
285      R->Destroy(*this);
286  }
287
288  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
289                                                    AEnd = DeclAttrs.end();
290       A != AEnd; ++A)
291    A->second->~AttrVec();
292
293  // Destroy the partial diagnostic allocator.
294  DiagAllocator->~PartialDiagnosticStorageAllocator();
295}
296
297void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
298  Deallocations.push_back(std::make_pair(Callback, Data));
299}
300
301void
302ASTContext::setExternalSource(OwningPtr<ExternalASTSource> &Source) {
303  ExternalSource.reset(Source.take());
304}
305
306void ASTContext::PrintStats() const {
307  llvm::errs() << "\n*** AST Context Stats:\n";
308  llvm::errs() << "  " << Types.size() << " types total.\n";
309
310  unsigned counts[] = {
311#define TYPE(Name, Parent) 0,
312#define ABSTRACT_TYPE(Name, Parent)
313#include "clang/AST/TypeNodes.def"
314    0 // Extra
315  };
316
317  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
318    Type *T = Types[i];
319    counts[(unsigned)T->getTypeClass()]++;
320  }
321
322  unsigned Idx = 0;
323  unsigned TotalBytes = 0;
324#define TYPE(Name, Parent)                                              \
325  if (counts[Idx])                                                      \
326    llvm::errs() << "    " << counts[Idx] << " " << #Name               \
327                 << " types\n";                                         \
328  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
329  ++Idx;
330#define ABSTRACT_TYPE(Name, Parent)
331#include "clang/AST/TypeNodes.def"
332
333  llvm::errs() << "Total bytes = " << TotalBytes << "\n";
334
335  // Implicit special member functions.
336  llvm::errs() << NumImplicitDefaultConstructorsDeclared << "/"
337               << NumImplicitDefaultConstructors
338               << " implicit default constructors created\n";
339  llvm::errs() << NumImplicitCopyConstructorsDeclared << "/"
340               << NumImplicitCopyConstructors
341               << " implicit copy constructors created\n";
342  if (getLangOptions().CPlusPlus)
343    llvm::errs() << NumImplicitMoveConstructorsDeclared << "/"
344                 << NumImplicitMoveConstructors
345                 << " implicit move constructors created\n";
346  llvm::errs() << NumImplicitCopyAssignmentOperatorsDeclared << "/"
347               << NumImplicitCopyAssignmentOperators
348               << " implicit copy assignment operators created\n";
349  if (getLangOptions().CPlusPlus)
350    llvm::errs() << NumImplicitMoveAssignmentOperatorsDeclared << "/"
351                 << NumImplicitMoveAssignmentOperators
352                 << " implicit move assignment operators created\n";
353  llvm::errs() << NumImplicitDestructorsDeclared << "/"
354               << NumImplicitDestructors
355               << " implicit destructors created\n";
356
357  if (ExternalSource.get()) {
358    llvm::errs() << "\n";
359    ExternalSource->PrintStats();
360  }
361
362  BumpAlloc.PrintStats();
363}
364
365TypedefDecl *ASTContext::getInt128Decl() const {
366  if (!Int128Decl) {
367    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(Int128Ty);
368    Int128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
369                                     getTranslationUnitDecl(),
370                                     SourceLocation(),
371                                     SourceLocation(),
372                                     &Idents.get("__int128_t"),
373                                     TInfo);
374  }
375
376  return Int128Decl;
377}
378
379TypedefDecl *ASTContext::getUInt128Decl() const {
380  if (!UInt128Decl) {
381    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(UnsignedInt128Ty);
382    UInt128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
383                                     getTranslationUnitDecl(),
384                                     SourceLocation(),
385                                     SourceLocation(),
386                                     &Idents.get("__uint128_t"),
387                                     TInfo);
388  }
389
390  return UInt128Decl;
391}
392
393void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
394  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
395  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
396  Types.push_back(Ty);
397}
398
399void ASTContext::InitBuiltinTypes(const TargetInfo &Target) {
400  assert((!this->Target || this->Target == &Target) &&
401         "Incorrect target reinitialization");
402  assert(VoidTy.isNull() && "Context reinitialized?");
403
404  this->Target = &Target;
405
406  ABI.reset(createCXXABI(Target));
407  AddrSpaceMap = getAddressSpaceMap(Target, LangOpts);
408
409  // C99 6.2.5p19.
410  InitBuiltinType(VoidTy,              BuiltinType::Void);
411
412  // C99 6.2.5p2.
413  InitBuiltinType(BoolTy,              BuiltinType::Bool);
414  // C99 6.2.5p3.
415  if (LangOpts.CharIsSigned)
416    InitBuiltinType(CharTy,            BuiltinType::Char_S);
417  else
418    InitBuiltinType(CharTy,            BuiltinType::Char_U);
419  // C99 6.2.5p4.
420  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
421  InitBuiltinType(ShortTy,             BuiltinType::Short);
422  InitBuiltinType(IntTy,               BuiltinType::Int);
423  InitBuiltinType(LongTy,              BuiltinType::Long);
424  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
425
426  // C99 6.2.5p6.
427  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
428  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
429  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
430  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
431  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
432
433  // C99 6.2.5p10.
434  InitBuiltinType(FloatTy,             BuiltinType::Float);
435  InitBuiltinType(DoubleTy,            BuiltinType::Double);
436  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
437
438  // GNU extension, 128-bit integers.
439  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
440  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
441
442  if (LangOpts.CPlusPlus) { // C++ 3.9.1p5
443    if (TargetInfo::isTypeSigned(Target.getWCharType()))
444      InitBuiltinType(WCharTy,           BuiltinType::WChar_S);
445    else  // -fshort-wchar makes wchar_t be unsigned.
446      InitBuiltinType(WCharTy,           BuiltinType::WChar_U);
447  } else // C99
448    WCharTy = getFromTargetType(Target.getWCharType());
449
450  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
451    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
452  else // C99
453    Char16Ty = getFromTargetType(Target.getChar16Type());
454
455  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
456    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
457  else // C99
458    Char32Ty = getFromTargetType(Target.getChar32Type());
459
460  // Placeholder type for type-dependent expressions whose type is
461  // completely unknown. No code should ever check a type against
462  // DependentTy and users should never see it; however, it is here to
463  // help diagnose failures to properly check for type-dependent
464  // expressions.
465  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
466
467  // Placeholder type for functions.
468  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
469
470  // Placeholder type for bound members.
471  InitBuiltinType(BoundMemberTy,       BuiltinType::BoundMember);
472
473  // Placeholder type for pseudo-objects.
474  InitBuiltinType(PseudoObjectTy,      BuiltinType::PseudoObject);
475
476  // "any" type; useful for debugger-like clients.
477  InitBuiltinType(UnknownAnyTy,        BuiltinType::UnknownAny);
478
479  // Placeholder type for unbridged ARC casts.
480  InitBuiltinType(ARCUnbridgedCastTy,  BuiltinType::ARCUnbridgedCast);
481
482  // C99 6.2.5p11.
483  FloatComplexTy      = getComplexType(FloatTy);
484  DoubleComplexTy     = getComplexType(DoubleTy);
485  LongDoubleComplexTy = getComplexType(LongDoubleTy);
486
487  BuiltinVaListType = QualType();
488
489  // Builtin types for 'id', 'Class', and 'SEL'.
490  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
491  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
492  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
493
494  ObjCConstantStringType = QualType();
495
496  // void * type
497  VoidPtrTy = getPointerType(VoidTy);
498
499  // nullptr type (C++0x 2.14.7)
500  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
501
502  // half type (OpenCL 6.1.1.1) / ARM NEON __fp16
503  InitBuiltinType(HalfTy, BuiltinType::Half);
504}
505
506DiagnosticsEngine &ASTContext::getDiagnostics() const {
507  return SourceMgr.getDiagnostics();
508}
509
510AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
511  AttrVec *&Result = DeclAttrs[D];
512  if (!Result) {
513    void *Mem = Allocate(sizeof(AttrVec));
514    Result = new (Mem) AttrVec;
515  }
516
517  return *Result;
518}
519
520/// \brief Erase the attributes corresponding to the given declaration.
521void ASTContext::eraseDeclAttrs(const Decl *D) {
522  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
523  if (Pos != DeclAttrs.end()) {
524    Pos->second->~AttrVec();
525    DeclAttrs.erase(Pos);
526  }
527}
528
529MemberSpecializationInfo *
530ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
531  assert(Var->isStaticDataMember() && "Not a static data member");
532  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
533    = InstantiatedFromStaticDataMember.find(Var);
534  if (Pos == InstantiatedFromStaticDataMember.end())
535    return 0;
536
537  return Pos->second;
538}
539
540void
541ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
542                                                TemplateSpecializationKind TSK,
543                                          SourceLocation PointOfInstantiation) {
544  assert(Inst->isStaticDataMember() && "Not a static data member");
545  assert(Tmpl->isStaticDataMember() && "Not a static data member");
546  assert(!InstantiatedFromStaticDataMember[Inst] &&
547         "Already noted what static data member was instantiated from");
548  InstantiatedFromStaticDataMember[Inst]
549    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
550}
551
552FunctionDecl *ASTContext::getClassScopeSpecializationPattern(
553                                                     const FunctionDecl *FD){
554  assert(FD && "Specialization is 0");
555  llvm::DenseMap<const FunctionDecl*, FunctionDecl *>::const_iterator Pos
556    = ClassScopeSpecializationPattern.find(FD);
557  if (Pos == ClassScopeSpecializationPattern.end())
558    return 0;
559
560  return Pos->second;
561}
562
563void ASTContext::setClassScopeSpecializationPattern(FunctionDecl *FD,
564                                        FunctionDecl *Pattern) {
565  assert(FD && "Specialization is 0");
566  assert(Pattern && "Class scope specialization pattern is 0");
567  ClassScopeSpecializationPattern[FD] = Pattern;
568}
569
570NamedDecl *
571ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
572  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
573    = InstantiatedFromUsingDecl.find(UUD);
574  if (Pos == InstantiatedFromUsingDecl.end())
575    return 0;
576
577  return Pos->second;
578}
579
580void
581ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
582  assert((isa<UsingDecl>(Pattern) ||
583          isa<UnresolvedUsingValueDecl>(Pattern) ||
584          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
585         "pattern decl is not a using decl");
586  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
587  InstantiatedFromUsingDecl[Inst] = Pattern;
588}
589
590UsingShadowDecl *
591ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
592  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
593    = InstantiatedFromUsingShadowDecl.find(Inst);
594  if (Pos == InstantiatedFromUsingShadowDecl.end())
595    return 0;
596
597  return Pos->second;
598}
599
600void
601ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
602                                               UsingShadowDecl *Pattern) {
603  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
604  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
605}
606
607FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
608  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
609    = InstantiatedFromUnnamedFieldDecl.find(Field);
610  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
611    return 0;
612
613  return Pos->second;
614}
615
616void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
617                                                     FieldDecl *Tmpl) {
618  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
619  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
620  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
621         "Already noted what unnamed field was instantiated from");
622
623  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
624}
625
626bool ASTContext::ZeroBitfieldFollowsNonBitfield(const FieldDecl *FD,
627                                    const FieldDecl *LastFD) const {
628  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
629          FD->getBitWidthValue(*this) == 0);
630}
631
632bool ASTContext::ZeroBitfieldFollowsBitfield(const FieldDecl *FD,
633                                             const FieldDecl *LastFD) const {
634  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
635          FD->getBitWidthValue(*this) == 0 &&
636          LastFD->getBitWidthValue(*this) != 0);
637}
638
639bool ASTContext::BitfieldFollowsBitfield(const FieldDecl *FD,
640                                         const FieldDecl *LastFD) const {
641  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
642          FD->getBitWidthValue(*this) &&
643          LastFD->getBitWidthValue(*this));
644}
645
646bool ASTContext::NonBitfieldFollowsBitfield(const FieldDecl *FD,
647                                         const FieldDecl *LastFD) const {
648  return (!FD->isBitField() && LastFD && LastFD->isBitField() &&
649          LastFD->getBitWidthValue(*this));
650}
651
652bool ASTContext::BitfieldFollowsNonBitfield(const FieldDecl *FD,
653                                             const FieldDecl *LastFD) const {
654  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
655          FD->getBitWidthValue(*this));
656}
657
658ASTContext::overridden_cxx_method_iterator
659ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
660  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
661    = OverriddenMethods.find(Method);
662  if (Pos == OverriddenMethods.end())
663    return 0;
664
665  return Pos->second.begin();
666}
667
668ASTContext::overridden_cxx_method_iterator
669ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
670  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
671    = OverriddenMethods.find(Method);
672  if (Pos == OverriddenMethods.end())
673    return 0;
674
675  return Pos->second.end();
676}
677
678unsigned
679ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
680  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
681    = OverriddenMethods.find(Method);
682  if (Pos == OverriddenMethods.end())
683    return 0;
684
685  return Pos->second.size();
686}
687
688void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
689                                     const CXXMethodDecl *Overridden) {
690  OverriddenMethods[Method].push_back(Overridden);
691}
692
693void ASTContext::addedLocalImportDecl(ImportDecl *Import) {
694  assert(!Import->NextLocalImport && "Import declaration already in the chain");
695  assert(!Import->isFromASTFile() && "Non-local import declaration");
696  if (!FirstLocalImport) {
697    FirstLocalImport = Import;
698    LastLocalImport = Import;
699    return;
700  }
701
702  LastLocalImport->NextLocalImport = Import;
703  LastLocalImport = Import;
704}
705
706//===----------------------------------------------------------------------===//
707//                         Type Sizing and Analysis
708//===----------------------------------------------------------------------===//
709
710/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
711/// scalar floating point type.
712const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
713  const BuiltinType *BT = T->getAs<BuiltinType>();
714  assert(BT && "Not a floating point type!");
715  switch (BT->getKind()) {
716  default: llvm_unreachable("Not a floating point type!");
717  case BuiltinType::Half:       return Target->getHalfFormat();
718  case BuiltinType::Float:      return Target->getFloatFormat();
719  case BuiltinType::Double:     return Target->getDoubleFormat();
720  case BuiltinType::LongDouble: return Target->getLongDoubleFormat();
721  }
722}
723
724/// getDeclAlign - Return a conservative estimate of the alignment of the
725/// specified decl.  Note that bitfields do not have a valid alignment, so
726/// this method will assert on them.
727/// If @p RefAsPointee, references are treated like their underlying type
728/// (for alignof), else they're treated like pointers (for CodeGen).
729CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) const {
730  unsigned Align = Target->getCharWidth();
731
732  bool UseAlignAttrOnly = false;
733  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
734    Align = AlignFromAttr;
735
736    // __attribute__((aligned)) can increase or decrease alignment
737    // *except* on a struct or struct member, where it only increases
738    // alignment unless 'packed' is also specified.
739    //
740    // It is an error for alignas to decrease alignment, so we can
741    // ignore that possibility;  Sema should diagnose it.
742    if (isa<FieldDecl>(D)) {
743      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
744        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
745    } else {
746      UseAlignAttrOnly = true;
747    }
748  }
749  else if (isa<FieldDecl>(D))
750      UseAlignAttrOnly =
751        D->hasAttr<PackedAttr>() ||
752        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
753
754  // If we're using the align attribute only, just ignore everything
755  // else about the declaration and its type.
756  if (UseAlignAttrOnly) {
757    // do nothing
758
759  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
760    QualType T = VD->getType();
761    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
762      if (RefAsPointee)
763        T = RT->getPointeeType();
764      else
765        T = getPointerType(RT->getPointeeType());
766    }
767    if (!T->isIncompleteType() && !T->isFunctionType()) {
768      // Adjust alignments of declarations with array type by the
769      // large-array alignment on the target.
770      unsigned MinWidth = Target->getLargeArrayMinWidth();
771      const ArrayType *arrayType;
772      if (MinWidth && (arrayType = getAsArrayType(T))) {
773        if (isa<VariableArrayType>(arrayType))
774          Align = std::max(Align, Target->getLargeArrayAlign());
775        else if (isa<ConstantArrayType>(arrayType) &&
776                 MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
777          Align = std::max(Align, Target->getLargeArrayAlign());
778
779        // Walk through any array types while we're at it.
780        T = getBaseElementType(arrayType);
781      }
782      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
783    }
784
785    // Fields can be subject to extra alignment constraints, like if
786    // the field is packed, the struct is packed, or the struct has a
787    // a max-field-alignment constraint (#pragma pack).  So calculate
788    // the actual alignment of the field within the struct, and then
789    // (as we're expected to) constrain that by the alignment of the type.
790    if (const FieldDecl *field = dyn_cast<FieldDecl>(VD)) {
791      // So calculate the alignment of the field.
792      const ASTRecordLayout &layout = getASTRecordLayout(field->getParent());
793
794      // Start with the record's overall alignment.
795      unsigned fieldAlign = toBits(layout.getAlignment());
796
797      // Use the GCD of that and the offset within the record.
798      uint64_t offset = layout.getFieldOffset(field->getFieldIndex());
799      if (offset > 0) {
800        // Alignment is always a power of 2, so the GCD will be a power of 2,
801        // which means we get to do this crazy thing instead of Euclid's.
802        uint64_t lowBitOfOffset = offset & (~offset + 1);
803        if (lowBitOfOffset < fieldAlign)
804          fieldAlign = static_cast<unsigned>(lowBitOfOffset);
805      }
806
807      Align = std::min(Align, fieldAlign);
808    }
809  }
810
811  return toCharUnitsFromBits(Align);
812}
813
814std::pair<CharUnits, CharUnits>
815ASTContext::getTypeInfoInChars(const Type *T) const {
816  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
817  return std::make_pair(toCharUnitsFromBits(Info.first),
818                        toCharUnitsFromBits(Info.second));
819}
820
821std::pair<CharUnits, CharUnits>
822ASTContext::getTypeInfoInChars(QualType T) const {
823  return getTypeInfoInChars(T.getTypePtr());
824}
825
826/// getTypeSize - Return the size of the specified type, in bits.  This method
827/// does not work on incomplete types.
828///
829/// FIXME: Pointers into different addr spaces could have different sizes and
830/// alignment requirements: getPointerInfo should take an AddrSpace, this
831/// should take a QualType, &c.
832std::pair<uint64_t, unsigned>
833ASTContext::getTypeInfo(const Type *T) const {
834  uint64_t Width=0;
835  unsigned Align=8;
836  switch (T->getTypeClass()) {
837#define TYPE(Class, Base)
838#define ABSTRACT_TYPE(Class, Base)
839#define NON_CANONICAL_TYPE(Class, Base)
840#define DEPENDENT_TYPE(Class, Base) case Type::Class:
841#include "clang/AST/TypeNodes.def"
842    llvm_unreachable("Should not see dependent types");
843
844  case Type::FunctionNoProto:
845  case Type::FunctionProto:
846    // GCC extension: alignof(function) = 32 bits
847    Width = 0;
848    Align = 32;
849    break;
850
851  case Type::IncompleteArray:
852  case Type::VariableArray:
853    Width = 0;
854    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
855    break;
856
857  case Type::ConstantArray: {
858    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
859
860    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
861    uint64_t Size = CAT->getSize().getZExtValue();
862    assert((Size == 0 || EltInfo.first <= (uint64_t)(-1)/Size) && "Overflow in array type bit size evaluation");
863    Width = EltInfo.first*Size;
864    Align = EltInfo.second;
865    Width = llvm::RoundUpToAlignment(Width, Align);
866    break;
867  }
868  case Type::ExtVector:
869  case Type::Vector: {
870    const VectorType *VT = cast<VectorType>(T);
871    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
872    Width = EltInfo.first*VT->getNumElements();
873    Align = Width;
874    // If the alignment is not a power of 2, round up to the next power of 2.
875    // This happens for non-power-of-2 length vectors.
876    if (Align & (Align-1)) {
877      Align = llvm::NextPowerOf2(Align);
878      Width = llvm::RoundUpToAlignment(Width, Align);
879    }
880    break;
881  }
882
883  case Type::Builtin:
884    switch (cast<BuiltinType>(T)->getKind()) {
885    default: llvm_unreachable("Unknown builtin type!");
886    case BuiltinType::Void:
887      // GCC extension: alignof(void) = 8 bits.
888      Width = 0;
889      Align = 8;
890      break;
891
892    case BuiltinType::Bool:
893      Width = Target->getBoolWidth();
894      Align = Target->getBoolAlign();
895      break;
896    case BuiltinType::Char_S:
897    case BuiltinType::Char_U:
898    case BuiltinType::UChar:
899    case BuiltinType::SChar:
900      Width = Target->getCharWidth();
901      Align = Target->getCharAlign();
902      break;
903    case BuiltinType::WChar_S:
904    case BuiltinType::WChar_U:
905      Width = Target->getWCharWidth();
906      Align = Target->getWCharAlign();
907      break;
908    case BuiltinType::Char16:
909      Width = Target->getChar16Width();
910      Align = Target->getChar16Align();
911      break;
912    case BuiltinType::Char32:
913      Width = Target->getChar32Width();
914      Align = Target->getChar32Align();
915      break;
916    case BuiltinType::UShort:
917    case BuiltinType::Short:
918      Width = Target->getShortWidth();
919      Align = Target->getShortAlign();
920      break;
921    case BuiltinType::UInt:
922    case BuiltinType::Int:
923      Width = Target->getIntWidth();
924      Align = Target->getIntAlign();
925      break;
926    case BuiltinType::ULong:
927    case BuiltinType::Long:
928      Width = Target->getLongWidth();
929      Align = Target->getLongAlign();
930      break;
931    case BuiltinType::ULongLong:
932    case BuiltinType::LongLong:
933      Width = Target->getLongLongWidth();
934      Align = Target->getLongLongAlign();
935      break;
936    case BuiltinType::Int128:
937    case BuiltinType::UInt128:
938      Width = 128;
939      Align = 128; // int128_t is 128-bit aligned on all targets.
940      break;
941    case BuiltinType::Half:
942      Width = Target->getHalfWidth();
943      Align = Target->getHalfAlign();
944      break;
945    case BuiltinType::Float:
946      Width = Target->getFloatWidth();
947      Align = Target->getFloatAlign();
948      break;
949    case BuiltinType::Double:
950      Width = Target->getDoubleWidth();
951      Align = Target->getDoubleAlign();
952      break;
953    case BuiltinType::LongDouble:
954      Width = Target->getLongDoubleWidth();
955      Align = Target->getLongDoubleAlign();
956      break;
957    case BuiltinType::NullPtr:
958      Width = Target->getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
959      Align = Target->getPointerAlign(0); //   == sizeof(void*)
960      break;
961    case BuiltinType::ObjCId:
962    case BuiltinType::ObjCClass:
963    case BuiltinType::ObjCSel:
964      Width = Target->getPointerWidth(0);
965      Align = Target->getPointerAlign(0);
966      break;
967    }
968    break;
969  case Type::ObjCObjectPointer:
970    Width = Target->getPointerWidth(0);
971    Align = Target->getPointerAlign(0);
972    break;
973  case Type::BlockPointer: {
974    unsigned AS = getTargetAddressSpace(
975        cast<BlockPointerType>(T)->getPointeeType());
976    Width = Target->getPointerWidth(AS);
977    Align = Target->getPointerAlign(AS);
978    break;
979  }
980  case Type::LValueReference:
981  case Type::RValueReference: {
982    // alignof and sizeof should never enter this code path here, so we go
983    // the pointer route.
984    unsigned AS = getTargetAddressSpace(
985        cast<ReferenceType>(T)->getPointeeType());
986    Width = Target->getPointerWidth(AS);
987    Align = Target->getPointerAlign(AS);
988    break;
989  }
990  case Type::Pointer: {
991    unsigned AS = getTargetAddressSpace(cast<PointerType>(T)->getPointeeType());
992    Width = Target->getPointerWidth(AS);
993    Align = Target->getPointerAlign(AS);
994    break;
995  }
996  case Type::MemberPointer: {
997    const MemberPointerType *MPT = cast<MemberPointerType>(T);
998    std::pair<uint64_t, unsigned> PtrDiffInfo =
999      getTypeInfo(getPointerDiffType());
1000    Width = PtrDiffInfo.first * ABI->getMemberPointerSize(MPT);
1001    Align = PtrDiffInfo.second;
1002    break;
1003  }
1004  case Type::Complex: {
1005    // Complex types have the same alignment as their elements, but twice the
1006    // size.
1007    std::pair<uint64_t, unsigned> EltInfo =
1008      getTypeInfo(cast<ComplexType>(T)->getElementType());
1009    Width = EltInfo.first*2;
1010    Align = EltInfo.second;
1011    break;
1012  }
1013  case Type::ObjCObject:
1014    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
1015  case Type::ObjCInterface: {
1016    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
1017    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
1018    Width = toBits(Layout.getSize());
1019    Align = toBits(Layout.getAlignment());
1020    break;
1021  }
1022  case Type::Record:
1023  case Type::Enum: {
1024    const TagType *TT = cast<TagType>(T);
1025
1026    if (TT->getDecl()->isInvalidDecl()) {
1027      Width = 8;
1028      Align = 8;
1029      break;
1030    }
1031
1032    if (const EnumType *ET = dyn_cast<EnumType>(TT))
1033      return getTypeInfo(ET->getDecl()->getIntegerType());
1034
1035    const RecordType *RT = cast<RecordType>(TT);
1036    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
1037    Width = toBits(Layout.getSize());
1038    Align = toBits(Layout.getAlignment());
1039    break;
1040  }
1041
1042  case Type::SubstTemplateTypeParm:
1043    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
1044                       getReplacementType().getTypePtr());
1045
1046  case Type::Auto: {
1047    const AutoType *A = cast<AutoType>(T);
1048    assert(A->isDeduced() && "Cannot request the size of a dependent type");
1049    return getTypeInfo(A->getDeducedType().getTypePtr());
1050  }
1051
1052  case Type::Paren:
1053    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
1054
1055  case Type::Typedef: {
1056    const TypedefNameDecl *Typedef = cast<TypedefType>(T)->getDecl();
1057    std::pair<uint64_t, unsigned> Info
1058      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
1059    // If the typedef has an aligned attribute on it, it overrides any computed
1060    // alignment we have.  This violates the GCC documentation (which says that
1061    // attribute(aligned) can only round up) but matches its implementation.
1062    if (unsigned AttrAlign = Typedef->getMaxAlignment())
1063      Align = AttrAlign;
1064    else
1065      Align = Info.second;
1066    Width = Info.first;
1067    break;
1068  }
1069
1070  case Type::TypeOfExpr:
1071    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
1072                         .getTypePtr());
1073
1074  case Type::TypeOf:
1075    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
1076
1077  case Type::Decltype:
1078    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
1079                        .getTypePtr());
1080
1081  case Type::UnaryTransform:
1082    return getTypeInfo(cast<UnaryTransformType>(T)->getUnderlyingType());
1083
1084  case Type::Elaborated:
1085    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
1086
1087  case Type::Attributed:
1088    return getTypeInfo(
1089                  cast<AttributedType>(T)->getEquivalentType().getTypePtr());
1090
1091  case Type::TemplateSpecialization: {
1092    assert(getCanonicalType(T) != T &&
1093           "Cannot request the size of a dependent type");
1094    const TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T);
1095    // A type alias template specialization may refer to a typedef with the
1096    // aligned attribute on it.
1097    if (TST->isTypeAlias())
1098      return getTypeInfo(TST->getAliasedType().getTypePtr());
1099    else
1100      return getTypeInfo(getCanonicalType(T));
1101  }
1102
1103  case Type::Atomic: {
1104    std::pair<uint64_t, unsigned> Info
1105      = getTypeInfo(cast<AtomicType>(T)->getValueType());
1106    Width = Info.first;
1107    Align = Info.second;
1108    if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth() &&
1109        llvm::isPowerOf2_64(Width)) {
1110      // We can potentially perform lock-free atomic operations for this
1111      // type; promote the alignment appropriately.
1112      // FIXME: We could potentially promote the width here as well...
1113      // is that worthwhile?  (Non-struct atomic types generally have
1114      // power-of-two size anyway, but structs might not.  Requires a bit
1115      // of implementation work to make sure we zero out the extra bits.)
1116      Align = static_cast<unsigned>(Width);
1117    }
1118  }
1119
1120  }
1121
1122  assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
1123  return std::make_pair(Width, Align);
1124}
1125
1126/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1127CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1128  return CharUnits::fromQuantity(BitSize / getCharWidth());
1129}
1130
1131/// toBits - Convert a size in characters to a size in characters.
1132int64_t ASTContext::toBits(CharUnits CharSize) const {
1133  return CharSize.getQuantity() * getCharWidth();
1134}
1135
1136/// getTypeSizeInChars - Return the size of the specified type, in characters.
1137/// This method does not work on incomplete types.
1138CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1139  return toCharUnitsFromBits(getTypeSize(T));
1140}
1141CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1142  return toCharUnitsFromBits(getTypeSize(T));
1143}
1144
1145/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1146/// characters. This method does not work on incomplete types.
1147CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1148  return toCharUnitsFromBits(getTypeAlign(T));
1149}
1150CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1151  return toCharUnitsFromBits(getTypeAlign(T));
1152}
1153
1154/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1155/// type for the current target in bits.  This can be different than the ABI
1156/// alignment in cases where it is beneficial for performance to overalign
1157/// a data type.
1158unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1159  unsigned ABIAlign = getTypeAlign(T);
1160
1161  // Double and long long should be naturally aligned if possible.
1162  if (const ComplexType* CT = T->getAs<ComplexType>())
1163    T = CT->getElementType().getTypePtr();
1164  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1165      T->isSpecificBuiltinType(BuiltinType::LongLong))
1166    return std::max(ABIAlign, (unsigned)getTypeSize(T));
1167
1168  return ABIAlign;
1169}
1170
1171/// DeepCollectObjCIvars -
1172/// This routine first collects all declared, but not synthesized, ivars in
1173/// super class and then collects all ivars, including those synthesized for
1174/// current class. This routine is used for implementation of current class
1175/// when all ivars, declared and synthesized are known.
1176///
1177void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1178                                      bool leafClass,
1179                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1180  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1181    DeepCollectObjCIvars(SuperClass, false, Ivars);
1182  if (!leafClass) {
1183    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
1184         E = OI->ivar_end(); I != E; ++I)
1185      Ivars.push_back(*I);
1186  } else {
1187    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1188    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1189         Iv= Iv->getNextIvar())
1190      Ivars.push_back(Iv);
1191  }
1192}
1193
1194/// CollectInheritedProtocols - Collect all protocols in current class and
1195/// those inherited by it.
1196void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1197                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1198  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1199    // We can use protocol_iterator here instead of
1200    // all_referenced_protocol_iterator since we are walking all categories.
1201    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
1202         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
1203      ObjCProtocolDecl *Proto = (*P);
1204      Protocols.insert(Proto->getCanonicalDecl());
1205      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1206           PE = Proto->protocol_end(); P != PE; ++P) {
1207        Protocols.insert((*P)->getCanonicalDecl());
1208        CollectInheritedProtocols(*P, Protocols);
1209      }
1210    }
1211
1212    // Categories of this Interface.
1213    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
1214         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
1215      CollectInheritedProtocols(CDeclChain, Protocols);
1216    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1217      while (SD) {
1218        CollectInheritedProtocols(SD, Protocols);
1219        SD = SD->getSuperClass();
1220      }
1221  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1222    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
1223         PE = OC->protocol_end(); P != PE; ++P) {
1224      ObjCProtocolDecl *Proto = (*P);
1225      Protocols.insert(Proto->getCanonicalDecl());
1226      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1227           PE = Proto->protocol_end(); P != PE; ++P)
1228        CollectInheritedProtocols(*P, Protocols);
1229    }
1230  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
1231    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
1232         PE = OP->protocol_end(); P != PE; ++P) {
1233      ObjCProtocolDecl *Proto = (*P);
1234      Protocols.insert(Proto->getCanonicalDecl());
1235      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1236           PE = Proto->protocol_end(); P != PE; ++P)
1237        CollectInheritedProtocols(*P, Protocols);
1238    }
1239  }
1240}
1241
1242unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
1243  unsigned count = 0;
1244  // Count ivars declared in class extension.
1245  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
1246       CDecl = CDecl->getNextClassExtension())
1247    count += CDecl->ivar_size();
1248
1249  // Count ivar defined in this class's implementation.  This
1250  // includes synthesized ivars.
1251  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
1252    count += ImplDecl->ivar_size();
1253
1254  return count;
1255}
1256
1257bool ASTContext::isSentinelNullExpr(const Expr *E) {
1258  if (!E)
1259    return false;
1260
1261  // nullptr_t is always treated as null.
1262  if (E->getType()->isNullPtrType()) return true;
1263
1264  if (E->getType()->isAnyPointerType() &&
1265      E->IgnoreParenCasts()->isNullPointerConstant(*this,
1266                                                Expr::NPC_ValueDependentIsNull))
1267    return true;
1268
1269  // Unfortunately, __null has type 'int'.
1270  if (isa<GNUNullExpr>(E)) return true;
1271
1272  return false;
1273}
1274
1275/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
1276ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
1277  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1278    I = ObjCImpls.find(D);
1279  if (I != ObjCImpls.end())
1280    return cast<ObjCImplementationDecl>(I->second);
1281  return 0;
1282}
1283/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
1284ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
1285  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1286    I = ObjCImpls.find(D);
1287  if (I != ObjCImpls.end())
1288    return cast<ObjCCategoryImplDecl>(I->second);
1289  return 0;
1290}
1291
1292/// \brief Set the implementation of ObjCInterfaceDecl.
1293void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1294                           ObjCImplementationDecl *ImplD) {
1295  assert(IFaceD && ImplD && "Passed null params");
1296  ObjCImpls[IFaceD] = ImplD;
1297}
1298/// \brief Set the implementation of ObjCCategoryDecl.
1299void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1300                           ObjCCategoryImplDecl *ImplD) {
1301  assert(CatD && ImplD && "Passed null params");
1302  ObjCImpls[CatD] = ImplD;
1303}
1304
1305ObjCInterfaceDecl *ASTContext::getObjContainingInterface(NamedDecl *ND) const {
1306  if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(ND->getDeclContext()))
1307    return ID;
1308  if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(ND->getDeclContext()))
1309    return CD->getClassInterface();
1310  if (ObjCImplDecl *IMD = dyn_cast<ObjCImplDecl>(ND->getDeclContext()))
1311    return IMD->getClassInterface();
1312
1313  return 0;
1314}
1315
1316/// \brief Get the copy initialization expression of VarDecl,or NULL if
1317/// none exists.
1318Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
1319  assert(VD && "Passed null params");
1320  assert(VD->hasAttr<BlocksAttr>() &&
1321         "getBlockVarCopyInits - not __block var");
1322  llvm::DenseMap<const VarDecl*, Expr*>::iterator
1323    I = BlockVarCopyInits.find(VD);
1324  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : 0;
1325}
1326
1327/// \brief Set the copy inialization expression of a block var decl.
1328void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
1329  assert(VD && Init && "Passed null params");
1330  assert(VD->hasAttr<BlocksAttr>() &&
1331         "setBlockVarCopyInits - not __block var");
1332  BlockVarCopyInits[VD] = Init;
1333}
1334
1335/// \brief Allocate an uninitialized TypeSourceInfo.
1336///
1337/// The caller should initialize the memory held by TypeSourceInfo using
1338/// the TypeLoc wrappers.
1339///
1340/// \param T the type that will be the basis for type source info. This type
1341/// should refer to how the declarator was written in source code, not to
1342/// what type semantic analysis resolved the declarator to.
1343TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1344                                                 unsigned DataSize) const {
1345  if (!DataSize)
1346    DataSize = TypeLoc::getFullDataSizeForType(T);
1347  else
1348    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1349           "incorrect data size provided to CreateTypeSourceInfo!");
1350
1351  TypeSourceInfo *TInfo =
1352    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1353  new (TInfo) TypeSourceInfo(T);
1354  return TInfo;
1355}
1356
1357TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1358                                                     SourceLocation L) const {
1359  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1360  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
1361  return DI;
1362}
1363
1364const ASTRecordLayout &
1365ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
1366  return getObjCLayout(D, 0);
1367}
1368
1369const ASTRecordLayout &
1370ASTContext::getASTObjCImplementationLayout(
1371                                        const ObjCImplementationDecl *D) const {
1372  return getObjCLayout(D->getClassInterface(), D);
1373}
1374
1375//===----------------------------------------------------------------------===//
1376//                   Type creation/memoization methods
1377//===----------------------------------------------------------------------===//
1378
1379QualType
1380ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
1381  unsigned fastQuals = quals.getFastQualifiers();
1382  quals.removeFastQualifiers();
1383
1384  // Check if we've already instantiated this type.
1385  llvm::FoldingSetNodeID ID;
1386  ExtQuals::Profile(ID, baseType, quals);
1387  void *insertPos = 0;
1388  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
1389    assert(eq->getQualifiers() == quals);
1390    return QualType(eq, fastQuals);
1391  }
1392
1393  // If the base type is not canonical, make the appropriate canonical type.
1394  QualType canon;
1395  if (!baseType->isCanonicalUnqualified()) {
1396    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
1397    canonSplit.second.addConsistentQualifiers(quals);
1398    canon = getExtQualType(canonSplit.first, canonSplit.second);
1399
1400    // Re-find the insert position.
1401    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
1402  }
1403
1404  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
1405  ExtQualNodes.InsertNode(eq, insertPos);
1406  return QualType(eq, fastQuals);
1407}
1408
1409QualType
1410ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
1411  QualType CanT = getCanonicalType(T);
1412  if (CanT.getAddressSpace() == AddressSpace)
1413    return T;
1414
1415  // If we are composing extended qualifiers together, merge together
1416  // into one ExtQuals node.
1417  QualifierCollector Quals;
1418  const Type *TypeNode = Quals.strip(T);
1419
1420  // If this type already has an address space specified, it cannot get
1421  // another one.
1422  assert(!Quals.hasAddressSpace() &&
1423         "Type cannot be in multiple addr spaces!");
1424  Quals.addAddressSpace(AddressSpace);
1425
1426  return getExtQualType(TypeNode, Quals);
1427}
1428
1429QualType ASTContext::getObjCGCQualType(QualType T,
1430                                       Qualifiers::GC GCAttr) const {
1431  QualType CanT = getCanonicalType(T);
1432  if (CanT.getObjCGCAttr() == GCAttr)
1433    return T;
1434
1435  if (const PointerType *ptr = T->getAs<PointerType>()) {
1436    QualType Pointee = ptr->getPointeeType();
1437    if (Pointee->isAnyPointerType()) {
1438      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1439      return getPointerType(ResultType);
1440    }
1441  }
1442
1443  // If we are composing extended qualifiers together, merge together
1444  // into one ExtQuals node.
1445  QualifierCollector Quals;
1446  const Type *TypeNode = Quals.strip(T);
1447
1448  // If this type already has an ObjCGC specified, it cannot get
1449  // another one.
1450  assert(!Quals.hasObjCGCAttr() &&
1451         "Type cannot have multiple ObjCGCs!");
1452  Quals.addObjCGCAttr(GCAttr);
1453
1454  return getExtQualType(TypeNode, Quals);
1455}
1456
1457const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
1458                                                   FunctionType::ExtInfo Info) {
1459  if (T->getExtInfo() == Info)
1460    return T;
1461
1462  QualType Result;
1463  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
1464    Result = getFunctionNoProtoType(FNPT->getResultType(), Info);
1465  } else {
1466    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
1467    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
1468    EPI.ExtInfo = Info;
1469    Result = getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1470                             FPT->getNumArgs(), EPI);
1471  }
1472
1473  return cast<FunctionType>(Result.getTypePtr());
1474}
1475
1476/// getComplexType - Return the uniqued reference to the type for a complex
1477/// number with the specified element type.
1478QualType ASTContext::getComplexType(QualType T) const {
1479  // Unique pointers, to guarantee there is only one pointer of a particular
1480  // structure.
1481  llvm::FoldingSetNodeID ID;
1482  ComplexType::Profile(ID, T);
1483
1484  void *InsertPos = 0;
1485  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1486    return QualType(CT, 0);
1487
1488  // If the pointee type isn't canonical, this won't be a canonical type either,
1489  // so fill in the canonical type field.
1490  QualType Canonical;
1491  if (!T.isCanonical()) {
1492    Canonical = getComplexType(getCanonicalType(T));
1493
1494    // Get the new insert position for the node we care about.
1495    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1496    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1497  }
1498  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1499  Types.push_back(New);
1500  ComplexTypes.InsertNode(New, InsertPos);
1501  return QualType(New, 0);
1502}
1503
1504/// getPointerType - Return the uniqued reference to the type for a pointer to
1505/// the specified type.
1506QualType ASTContext::getPointerType(QualType T) const {
1507  // Unique pointers, to guarantee there is only one pointer of a particular
1508  // structure.
1509  llvm::FoldingSetNodeID ID;
1510  PointerType::Profile(ID, T);
1511
1512  void *InsertPos = 0;
1513  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1514    return QualType(PT, 0);
1515
1516  // If the pointee type isn't canonical, this won't be a canonical type either,
1517  // so fill in the canonical type field.
1518  QualType Canonical;
1519  if (!T.isCanonical()) {
1520    Canonical = getPointerType(getCanonicalType(T));
1521
1522    // Get the new insert position for the node we care about.
1523    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1524    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1525  }
1526  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1527  Types.push_back(New);
1528  PointerTypes.InsertNode(New, InsertPos);
1529  return QualType(New, 0);
1530}
1531
1532/// getBlockPointerType - Return the uniqued reference to the type for
1533/// a pointer to the specified block.
1534QualType ASTContext::getBlockPointerType(QualType T) const {
1535  assert(T->isFunctionType() && "block of function types only");
1536  // Unique pointers, to guarantee there is only one block of a particular
1537  // structure.
1538  llvm::FoldingSetNodeID ID;
1539  BlockPointerType::Profile(ID, T);
1540
1541  void *InsertPos = 0;
1542  if (BlockPointerType *PT =
1543        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1544    return QualType(PT, 0);
1545
1546  // If the block pointee type isn't canonical, this won't be a canonical
1547  // type either so fill in the canonical type field.
1548  QualType Canonical;
1549  if (!T.isCanonical()) {
1550    Canonical = getBlockPointerType(getCanonicalType(T));
1551
1552    // Get the new insert position for the node we care about.
1553    BlockPointerType *NewIP =
1554      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1555    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1556  }
1557  BlockPointerType *New
1558    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1559  Types.push_back(New);
1560  BlockPointerTypes.InsertNode(New, InsertPos);
1561  return QualType(New, 0);
1562}
1563
1564/// getLValueReferenceType - Return the uniqued reference to the type for an
1565/// lvalue reference to the specified type.
1566QualType
1567ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
1568  assert(getCanonicalType(T) != OverloadTy &&
1569         "Unresolved overloaded function type");
1570
1571  // Unique pointers, to guarantee there is only one pointer of a particular
1572  // structure.
1573  llvm::FoldingSetNodeID ID;
1574  ReferenceType::Profile(ID, T, SpelledAsLValue);
1575
1576  void *InsertPos = 0;
1577  if (LValueReferenceType *RT =
1578        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1579    return QualType(RT, 0);
1580
1581  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1582
1583  // If the referencee type isn't canonical, this won't be a canonical type
1584  // either, so fill in the canonical type field.
1585  QualType Canonical;
1586  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1587    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1588    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1589
1590    // Get the new insert position for the node we care about.
1591    LValueReferenceType *NewIP =
1592      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1593    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1594  }
1595
1596  LValueReferenceType *New
1597    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1598                                                     SpelledAsLValue);
1599  Types.push_back(New);
1600  LValueReferenceTypes.InsertNode(New, InsertPos);
1601
1602  return QualType(New, 0);
1603}
1604
1605/// getRValueReferenceType - Return the uniqued reference to the type for an
1606/// rvalue reference to the specified type.
1607QualType ASTContext::getRValueReferenceType(QualType T) const {
1608  // Unique pointers, to guarantee there is only one pointer of a particular
1609  // structure.
1610  llvm::FoldingSetNodeID ID;
1611  ReferenceType::Profile(ID, T, false);
1612
1613  void *InsertPos = 0;
1614  if (RValueReferenceType *RT =
1615        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1616    return QualType(RT, 0);
1617
1618  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1619
1620  // If the referencee type isn't canonical, this won't be a canonical type
1621  // either, so fill in the canonical type field.
1622  QualType Canonical;
1623  if (InnerRef || !T.isCanonical()) {
1624    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1625    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1626
1627    // Get the new insert position for the node we care about.
1628    RValueReferenceType *NewIP =
1629      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1630    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1631  }
1632
1633  RValueReferenceType *New
1634    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1635  Types.push_back(New);
1636  RValueReferenceTypes.InsertNode(New, InsertPos);
1637  return QualType(New, 0);
1638}
1639
1640/// getMemberPointerType - Return the uniqued reference to the type for a
1641/// member pointer to the specified type, in the specified class.
1642QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
1643  // Unique pointers, to guarantee there is only one pointer of a particular
1644  // structure.
1645  llvm::FoldingSetNodeID ID;
1646  MemberPointerType::Profile(ID, T, Cls);
1647
1648  void *InsertPos = 0;
1649  if (MemberPointerType *PT =
1650      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1651    return QualType(PT, 0);
1652
1653  // If the pointee or class type isn't canonical, this won't be a canonical
1654  // type either, so fill in the canonical type field.
1655  QualType Canonical;
1656  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1657    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1658
1659    // Get the new insert position for the node we care about.
1660    MemberPointerType *NewIP =
1661      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1662    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1663  }
1664  MemberPointerType *New
1665    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1666  Types.push_back(New);
1667  MemberPointerTypes.InsertNode(New, InsertPos);
1668  return QualType(New, 0);
1669}
1670
1671/// getConstantArrayType - Return the unique reference to the type for an
1672/// array of the specified element type.
1673QualType ASTContext::getConstantArrayType(QualType EltTy,
1674                                          const llvm::APInt &ArySizeIn,
1675                                          ArrayType::ArraySizeModifier ASM,
1676                                          unsigned IndexTypeQuals) const {
1677  assert((EltTy->isDependentType() ||
1678          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1679         "Constant array of VLAs is illegal!");
1680
1681  // Convert the array size into a canonical width matching the pointer size for
1682  // the target.
1683  llvm::APInt ArySize(ArySizeIn);
1684  ArySize =
1685    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
1686
1687  llvm::FoldingSetNodeID ID;
1688  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
1689
1690  void *InsertPos = 0;
1691  if (ConstantArrayType *ATP =
1692      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1693    return QualType(ATP, 0);
1694
1695  // If the element type isn't canonical or has qualifiers, this won't
1696  // be a canonical type either, so fill in the canonical type field.
1697  QualType Canon;
1698  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1699    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1700    Canon = getConstantArrayType(QualType(canonSplit.first, 0), ArySize,
1701                                 ASM, IndexTypeQuals);
1702    Canon = getQualifiedType(Canon, canonSplit.second);
1703
1704    // Get the new insert position for the node we care about.
1705    ConstantArrayType *NewIP =
1706      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1707    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1708  }
1709
1710  ConstantArrayType *New = new(*this,TypeAlignment)
1711    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
1712  ConstantArrayTypes.InsertNode(New, InsertPos);
1713  Types.push_back(New);
1714  return QualType(New, 0);
1715}
1716
1717/// getVariableArrayDecayedType - Turns the given type, which may be
1718/// variably-modified, into the corresponding type with all the known
1719/// sizes replaced with [*].
1720QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
1721  // Vastly most common case.
1722  if (!type->isVariablyModifiedType()) return type;
1723
1724  QualType result;
1725
1726  SplitQualType split = type.getSplitDesugaredType();
1727  const Type *ty = split.first;
1728  switch (ty->getTypeClass()) {
1729#define TYPE(Class, Base)
1730#define ABSTRACT_TYPE(Class, Base)
1731#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
1732#include "clang/AST/TypeNodes.def"
1733    llvm_unreachable("didn't desugar past all non-canonical types?");
1734
1735  // These types should never be variably-modified.
1736  case Type::Builtin:
1737  case Type::Complex:
1738  case Type::Vector:
1739  case Type::ExtVector:
1740  case Type::DependentSizedExtVector:
1741  case Type::ObjCObject:
1742  case Type::ObjCInterface:
1743  case Type::ObjCObjectPointer:
1744  case Type::Record:
1745  case Type::Enum:
1746  case Type::UnresolvedUsing:
1747  case Type::TypeOfExpr:
1748  case Type::TypeOf:
1749  case Type::Decltype:
1750  case Type::UnaryTransform:
1751  case Type::DependentName:
1752  case Type::InjectedClassName:
1753  case Type::TemplateSpecialization:
1754  case Type::DependentTemplateSpecialization:
1755  case Type::TemplateTypeParm:
1756  case Type::SubstTemplateTypeParmPack:
1757  case Type::Auto:
1758  case Type::PackExpansion:
1759    llvm_unreachable("type should never be variably-modified");
1760
1761  // These types can be variably-modified but should never need to
1762  // further decay.
1763  case Type::FunctionNoProto:
1764  case Type::FunctionProto:
1765  case Type::BlockPointer:
1766  case Type::MemberPointer:
1767    return type;
1768
1769  // These types can be variably-modified.  All these modifications
1770  // preserve structure except as noted by comments.
1771  // TODO: if we ever care about optimizing VLAs, there are no-op
1772  // optimizations available here.
1773  case Type::Pointer:
1774    result = getPointerType(getVariableArrayDecayedType(
1775                              cast<PointerType>(ty)->getPointeeType()));
1776    break;
1777
1778  case Type::LValueReference: {
1779    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
1780    result = getLValueReferenceType(
1781                 getVariableArrayDecayedType(lv->getPointeeType()),
1782                                    lv->isSpelledAsLValue());
1783    break;
1784  }
1785
1786  case Type::RValueReference: {
1787    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
1788    result = getRValueReferenceType(
1789                 getVariableArrayDecayedType(lv->getPointeeType()));
1790    break;
1791  }
1792
1793  case Type::Atomic: {
1794    const AtomicType *at = cast<AtomicType>(ty);
1795    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
1796    break;
1797  }
1798
1799  case Type::ConstantArray: {
1800    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
1801    result = getConstantArrayType(
1802                 getVariableArrayDecayedType(cat->getElementType()),
1803                                  cat->getSize(),
1804                                  cat->getSizeModifier(),
1805                                  cat->getIndexTypeCVRQualifiers());
1806    break;
1807  }
1808
1809  case Type::DependentSizedArray: {
1810    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
1811    result = getDependentSizedArrayType(
1812                 getVariableArrayDecayedType(dat->getElementType()),
1813                                        dat->getSizeExpr(),
1814                                        dat->getSizeModifier(),
1815                                        dat->getIndexTypeCVRQualifiers(),
1816                                        dat->getBracketsRange());
1817    break;
1818  }
1819
1820  // Turn incomplete types into [*] types.
1821  case Type::IncompleteArray: {
1822    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
1823    result = getVariableArrayType(
1824                 getVariableArrayDecayedType(iat->getElementType()),
1825                                  /*size*/ 0,
1826                                  ArrayType::Normal,
1827                                  iat->getIndexTypeCVRQualifiers(),
1828                                  SourceRange());
1829    break;
1830  }
1831
1832  // Turn VLA types into [*] types.
1833  case Type::VariableArray: {
1834    const VariableArrayType *vat = cast<VariableArrayType>(ty);
1835    result = getVariableArrayType(
1836                 getVariableArrayDecayedType(vat->getElementType()),
1837                                  /*size*/ 0,
1838                                  ArrayType::Star,
1839                                  vat->getIndexTypeCVRQualifiers(),
1840                                  vat->getBracketsRange());
1841    break;
1842  }
1843  }
1844
1845  // Apply the top-level qualifiers from the original.
1846  return getQualifiedType(result, split.second);
1847}
1848
1849/// getVariableArrayType - Returns a non-unique reference to the type for a
1850/// variable array of the specified element type.
1851QualType ASTContext::getVariableArrayType(QualType EltTy,
1852                                          Expr *NumElts,
1853                                          ArrayType::ArraySizeModifier ASM,
1854                                          unsigned IndexTypeQuals,
1855                                          SourceRange Brackets) const {
1856  // Since we don't unique expressions, it isn't possible to unique VLA's
1857  // that have an expression provided for their size.
1858  QualType Canon;
1859
1860  // Be sure to pull qualifiers off the element type.
1861  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1862    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1863    Canon = getVariableArrayType(QualType(canonSplit.first, 0), NumElts, ASM,
1864                                 IndexTypeQuals, Brackets);
1865    Canon = getQualifiedType(Canon, canonSplit.second);
1866  }
1867
1868  VariableArrayType *New = new(*this, TypeAlignment)
1869    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
1870
1871  VariableArrayTypes.push_back(New);
1872  Types.push_back(New);
1873  return QualType(New, 0);
1874}
1875
1876/// getDependentSizedArrayType - Returns a non-unique reference to
1877/// the type for a dependently-sized array of the specified element
1878/// type.
1879QualType ASTContext::getDependentSizedArrayType(QualType elementType,
1880                                                Expr *numElements,
1881                                                ArrayType::ArraySizeModifier ASM,
1882                                                unsigned elementTypeQuals,
1883                                                SourceRange brackets) const {
1884  assert((!numElements || numElements->isTypeDependent() ||
1885          numElements->isValueDependent()) &&
1886         "Size must be type- or value-dependent!");
1887
1888  // Dependently-sized array types that do not have a specified number
1889  // of elements will have their sizes deduced from a dependent
1890  // initializer.  We do no canonicalization here at all, which is okay
1891  // because they can't be used in most locations.
1892  if (!numElements) {
1893    DependentSizedArrayType *newType
1894      = new (*this, TypeAlignment)
1895          DependentSizedArrayType(*this, elementType, QualType(),
1896                                  numElements, ASM, elementTypeQuals,
1897                                  brackets);
1898    Types.push_back(newType);
1899    return QualType(newType, 0);
1900  }
1901
1902  // Otherwise, we actually build a new type every time, but we
1903  // also build a canonical type.
1904
1905  SplitQualType canonElementType = getCanonicalType(elementType).split();
1906
1907  void *insertPos = 0;
1908  llvm::FoldingSetNodeID ID;
1909  DependentSizedArrayType::Profile(ID, *this,
1910                                   QualType(canonElementType.first, 0),
1911                                   ASM, elementTypeQuals, numElements);
1912
1913  // Look for an existing type with these properties.
1914  DependentSizedArrayType *canonTy =
1915    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1916
1917  // If we don't have one, build one.
1918  if (!canonTy) {
1919    canonTy = new (*this, TypeAlignment)
1920      DependentSizedArrayType(*this, QualType(canonElementType.first, 0),
1921                              QualType(), numElements, ASM, elementTypeQuals,
1922                              brackets);
1923    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
1924    Types.push_back(canonTy);
1925  }
1926
1927  // Apply qualifiers from the element type to the array.
1928  QualType canon = getQualifiedType(QualType(canonTy,0),
1929                                    canonElementType.second);
1930
1931  // If we didn't need extra canonicalization for the element type,
1932  // then just use that as our result.
1933  if (QualType(canonElementType.first, 0) == elementType)
1934    return canon;
1935
1936  // Otherwise, we need to build a type which follows the spelling
1937  // of the element type.
1938  DependentSizedArrayType *sugaredType
1939    = new (*this, TypeAlignment)
1940        DependentSizedArrayType(*this, elementType, canon, numElements,
1941                                ASM, elementTypeQuals, brackets);
1942  Types.push_back(sugaredType);
1943  return QualType(sugaredType, 0);
1944}
1945
1946QualType ASTContext::getIncompleteArrayType(QualType elementType,
1947                                            ArrayType::ArraySizeModifier ASM,
1948                                            unsigned elementTypeQuals) const {
1949  llvm::FoldingSetNodeID ID;
1950  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
1951
1952  void *insertPos = 0;
1953  if (IncompleteArrayType *iat =
1954       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
1955    return QualType(iat, 0);
1956
1957  // If the element type isn't canonical, this won't be a canonical type
1958  // either, so fill in the canonical type field.  We also have to pull
1959  // qualifiers off the element type.
1960  QualType canon;
1961
1962  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
1963    SplitQualType canonSplit = getCanonicalType(elementType).split();
1964    canon = getIncompleteArrayType(QualType(canonSplit.first, 0),
1965                                   ASM, elementTypeQuals);
1966    canon = getQualifiedType(canon, canonSplit.second);
1967
1968    // Get the new insert position for the node we care about.
1969    IncompleteArrayType *existing =
1970      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1971    assert(!existing && "Shouldn't be in the map!"); (void) existing;
1972  }
1973
1974  IncompleteArrayType *newType = new (*this, TypeAlignment)
1975    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
1976
1977  IncompleteArrayTypes.InsertNode(newType, insertPos);
1978  Types.push_back(newType);
1979  return QualType(newType, 0);
1980}
1981
1982/// getVectorType - Return the unique reference to a vector type of
1983/// the specified element type and size. VectorType must be a built-in type.
1984QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1985                                   VectorType::VectorKind VecKind) const {
1986  assert(vecType->isBuiltinType());
1987
1988  // Check if we've already instantiated a vector of this type.
1989  llvm::FoldingSetNodeID ID;
1990  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
1991
1992  void *InsertPos = 0;
1993  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1994    return QualType(VTP, 0);
1995
1996  // If the element type isn't canonical, this won't be a canonical type either,
1997  // so fill in the canonical type field.
1998  QualType Canonical;
1999  if (!vecType.isCanonical()) {
2000    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
2001
2002    // Get the new insert position for the node we care about.
2003    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2004    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2005  }
2006  VectorType *New = new (*this, TypeAlignment)
2007    VectorType(vecType, NumElts, Canonical, VecKind);
2008  VectorTypes.InsertNode(New, InsertPos);
2009  Types.push_back(New);
2010  return QualType(New, 0);
2011}
2012
2013/// getExtVectorType - Return the unique reference to an extended vector type of
2014/// the specified element type and size. VectorType must be a built-in type.
2015QualType
2016ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
2017  assert(vecType->isBuiltinType() || vecType->isDependentType());
2018
2019  // Check if we've already instantiated a vector of this type.
2020  llvm::FoldingSetNodeID ID;
2021  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
2022                      VectorType::GenericVector);
2023  void *InsertPos = 0;
2024  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2025    return QualType(VTP, 0);
2026
2027  // If the element type isn't canonical, this won't be a canonical type either,
2028  // so fill in the canonical type field.
2029  QualType Canonical;
2030  if (!vecType.isCanonical()) {
2031    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
2032
2033    // Get the new insert position for the node we care about.
2034    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2035    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2036  }
2037  ExtVectorType *New = new (*this, TypeAlignment)
2038    ExtVectorType(vecType, NumElts, Canonical);
2039  VectorTypes.InsertNode(New, InsertPos);
2040  Types.push_back(New);
2041  return QualType(New, 0);
2042}
2043
2044QualType
2045ASTContext::getDependentSizedExtVectorType(QualType vecType,
2046                                           Expr *SizeExpr,
2047                                           SourceLocation AttrLoc) const {
2048  llvm::FoldingSetNodeID ID;
2049  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
2050                                       SizeExpr);
2051
2052  void *InsertPos = 0;
2053  DependentSizedExtVectorType *Canon
2054    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2055  DependentSizedExtVectorType *New;
2056  if (Canon) {
2057    // We already have a canonical version of this array type; use it as
2058    // the canonical type for a newly-built type.
2059    New = new (*this, TypeAlignment)
2060      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
2061                                  SizeExpr, AttrLoc);
2062  } else {
2063    QualType CanonVecTy = getCanonicalType(vecType);
2064    if (CanonVecTy == vecType) {
2065      New = new (*this, TypeAlignment)
2066        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
2067                                    AttrLoc);
2068
2069      DependentSizedExtVectorType *CanonCheck
2070        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2071      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
2072      (void)CanonCheck;
2073      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
2074    } else {
2075      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
2076                                                      SourceLocation());
2077      New = new (*this, TypeAlignment)
2078        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2079    }
2080  }
2081
2082  Types.push_back(New);
2083  return QualType(New, 0);
2084}
2085
2086/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
2087///
2088QualType
2089ASTContext::getFunctionNoProtoType(QualType ResultTy,
2090                                   const FunctionType::ExtInfo &Info) const {
2091  const CallingConv DefaultCC = Info.getCC();
2092  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2093                               CC_X86StdCall : DefaultCC;
2094  // Unique functions, to guarantee there is only one function of a particular
2095  // structure.
2096  llvm::FoldingSetNodeID ID;
2097  FunctionNoProtoType::Profile(ID, ResultTy, Info);
2098
2099  void *InsertPos = 0;
2100  if (FunctionNoProtoType *FT =
2101        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2102    return QualType(FT, 0);
2103
2104  QualType Canonical;
2105  if (!ResultTy.isCanonical() ||
2106      getCanonicalCallConv(CallConv) != CallConv) {
2107    Canonical =
2108      getFunctionNoProtoType(getCanonicalType(ResultTy),
2109                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
2110
2111    // Get the new insert position for the node we care about.
2112    FunctionNoProtoType *NewIP =
2113      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2114    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2115  }
2116
2117  FunctionProtoType::ExtInfo newInfo = Info.withCallingConv(CallConv);
2118  FunctionNoProtoType *New = new (*this, TypeAlignment)
2119    FunctionNoProtoType(ResultTy, Canonical, newInfo);
2120  Types.push_back(New);
2121  FunctionNoProtoTypes.InsertNode(New, InsertPos);
2122  return QualType(New, 0);
2123}
2124
2125/// getFunctionType - Return a normal function type with a typed argument
2126/// list.  isVariadic indicates whether the argument list includes '...'.
2127QualType
2128ASTContext::getFunctionType(QualType ResultTy,
2129                            const QualType *ArgArray, unsigned NumArgs,
2130                            const FunctionProtoType::ExtProtoInfo &EPI) const {
2131  // Unique functions, to guarantee there is only one function of a particular
2132  // structure.
2133  llvm::FoldingSetNodeID ID;
2134  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, EPI, *this);
2135
2136  void *InsertPos = 0;
2137  if (FunctionProtoType *FTP =
2138        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2139    return QualType(FTP, 0);
2140
2141  // Determine whether the type being created is already canonical or not.
2142  bool isCanonical= EPI.ExceptionSpecType == EST_None && ResultTy.isCanonical();
2143  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
2144    if (!ArgArray[i].isCanonicalAsParam())
2145      isCanonical = false;
2146
2147  const CallingConv DefaultCC = EPI.ExtInfo.getCC();
2148  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2149                               CC_X86StdCall : DefaultCC;
2150
2151  // If this type isn't canonical, get the canonical version of it.
2152  // The exception spec is not part of the canonical type.
2153  QualType Canonical;
2154  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
2155    SmallVector<QualType, 16> CanonicalArgs;
2156    CanonicalArgs.reserve(NumArgs);
2157    for (unsigned i = 0; i != NumArgs; ++i)
2158      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
2159
2160    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
2161    CanonicalEPI.ExceptionSpecType = EST_None;
2162    CanonicalEPI.NumExceptions = 0;
2163    CanonicalEPI.ExtInfo
2164      = CanonicalEPI.ExtInfo.withCallingConv(getCanonicalCallConv(CallConv));
2165
2166    Canonical = getFunctionType(getCanonicalType(ResultTy),
2167                                CanonicalArgs.data(), NumArgs,
2168                                CanonicalEPI);
2169
2170    // Get the new insert position for the node we care about.
2171    FunctionProtoType *NewIP =
2172      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2173    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2174  }
2175
2176  // FunctionProtoType objects are allocated with extra bytes after
2177  // them for three variable size arrays at the end:
2178  //  - parameter types
2179  //  - exception types
2180  //  - consumed-arguments flags
2181  // Instead of the exception types, there could be a noexcept
2182  // expression.
2183  size_t Size = sizeof(FunctionProtoType) +
2184                NumArgs * sizeof(QualType);
2185  if (EPI.ExceptionSpecType == EST_Dynamic)
2186    Size += EPI.NumExceptions * sizeof(QualType);
2187  else if (EPI.ExceptionSpecType == EST_ComputedNoexcept) {
2188    Size += sizeof(Expr*);
2189  }
2190  if (EPI.ConsumedArguments)
2191    Size += NumArgs * sizeof(bool);
2192
2193  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
2194  FunctionProtoType::ExtProtoInfo newEPI = EPI;
2195  newEPI.ExtInfo = EPI.ExtInfo.withCallingConv(CallConv);
2196  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, Canonical, newEPI);
2197  Types.push_back(FTP);
2198  FunctionProtoTypes.InsertNode(FTP, InsertPos);
2199  return QualType(FTP, 0);
2200}
2201
2202#ifndef NDEBUG
2203static bool NeedsInjectedClassNameType(const RecordDecl *D) {
2204  if (!isa<CXXRecordDecl>(D)) return false;
2205  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
2206  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
2207    return true;
2208  if (RD->getDescribedClassTemplate() &&
2209      !isa<ClassTemplateSpecializationDecl>(RD))
2210    return true;
2211  return false;
2212}
2213#endif
2214
2215/// getInjectedClassNameType - Return the unique reference to the
2216/// injected class name type for the specified templated declaration.
2217QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
2218                                              QualType TST) const {
2219  assert(NeedsInjectedClassNameType(Decl));
2220  if (Decl->TypeForDecl) {
2221    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2222  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDecl()) {
2223    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
2224    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2225    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2226  } else {
2227    Type *newType =
2228      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
2229    Decl->TypeForDecl = newType;
2230    Types.push_back(newType);
2231  }
2232  return QualType(Decl->TypeForDecl, 0);
2233}
2234
2235/// getTypeDeclType - Return the unique reference to the type for the
2236/// specified type declaration.
2237QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) const {
2238  assert(Decl && "Passed null for Decl param");
2239  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
2240
2241  if (const TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Decl))
2242    return getTypedefType(Typedef);
2243
2244  assert(!isa<TemplateTypeParmDecl>(Decl) &&
2245         "Template type parameter types are always available.");
2246
2247  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
2248    assert(!Record->getPreviousDecl() &&
2249           "struct/union has previous declaration");
2250    assert(!NeedsInjectedClassNameType(Record));
2251    return getRecordType(Record);
2252  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
2253    assert(!Enum->getPreviousDecl() &&
2254           "enum has previous declaration");
2255    return getEnumType(Enum);
2256  } else if (const UnresolvedUsingTypenameDecl *Using =
2257               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
2258    Type *newType = new (*this, TypeAlignment) UnresolvedUsingType(Using);
2259    Decl->TypeForDecl = newType;
2260    Types.push_back(newType);
2261  } else
2262    llvm_unreachable("TypeDecl without a type?");
2263
2264  return QualType(Decl->TypeForDecl, 0);
2265}
2266
2267/// getTypedefType - Return the unique reference to the type for the
2268/// specified typedef name decl.
2269QualType
2270ASTContext::getTypedefType(const TypedefNameDecl *Decl,
2271                           QualType Canonical) const {
2272  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2273
2274  if (Canonical.isNull())
2275    Canonical = getCanonicalType(Decl->getUnderlyingType());
2276  TypedefType *newType = new(*this, TypeAlignment)
2277    TypedefType(Type::Typedef, Decl, Canonical);
2278  Decl->TypeForDecl = newType;
2279  Types.push_back(newType);
2280  return QualType(newType, 0);
2281}
2282
2283QualType ASTContext::getRecordType(const RecordDecl *Decl) const {
2284  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2285
2286  if (const RecordDecl *PrevDecl = Decl->getPreviousDecl())
2287    if (PrevDecl->TypeForDecl)
2288      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2289
2290  RecordType *newType = new (*this, TypeAlignment) RecordType(Decl);
2291  Decl->TypeForDecl = newType;
2292  Types.push_back(newType);
2293  return QualType(newType, 0);
2294}
2295
2296QualType ASTContext::getEnumType(const EnumDecl *Decl) const {
2297  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2298
2299  if (const EnumDecl *PrevDecl = Decl->getPreviousDecl())
2300    if (PrevDecl->TypeForDecl)
2301      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2302
2303  EnumType *newType = new (*this, TypeAlignment) EnumType(Decl);
2304  Decl->TypeForDecl = newType;
2305  Types.push_back(newType);
2306  return QualType(newType, 0);
2307}
2308
2309QualType ASTContext::getAttributedType(AttributedType::Kind attrKind,
2310                                       QualType modifiedType,
2311                                       QualType equivalentType) {
2312  llvm::FoldingSetNodeID id;
2313  AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
2314
2315  void *insertPos = 0;
2316  AttributedType *type = AttributedTypes.FindNodeOrInsertPos(id, insertPos);
2317  if (type) return QualType(type, 0);
2318
2319  QualType canon = getCanonicalType(equivalentType);
2320  type = new (*this, TypeAlignment)
2321           AttributedType(canon, attrKind, modifiedType, equivalentType);
2322
2323  Types.push_back(type);
2324  AttributedTypes.InsertNode(type, insertPos);
2325
2326  return QualType(type, 0);
2327}
2328
2329
2330/// \brief Retrieve a substitution-result type.
2331QualType
2332ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
2333                                         QualType Replacement) const {
2334  assert(Replacement.isCanonical()
2335         && "replacement types must always be canonical");
2336
2337  llvm::FoldingSetNodeID ID;
2338  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
2339  void *InsertPos = 0;
2340  SubstTemplateTypeParmType *SubstParm
2341    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2342
2343  if (!SubstParm) {
2344    SubstParm = new (*this, TypeAlignment)
2345      SubstTemplateTypeParmType(Parm, Replacement);
2346    Types.push_back(SubstParm);
2347    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2348  }
2349
2350  return QualType(SubstParm, 0);
2351}
2352
2353/// \brief Retrieve a
2354QualType ASTContext::getSubstTemplateTypeParmPackType(
2355                                          const TemplateTypeParmType *Parm,
2356                                              const TemplateArgument &ArgPack) {
2357#ifndef NDEBUG
2358  for (TemplateArgument::pack_iterator P = ArgPack.pack_begin(),
2359                                    PEnd = ArgPack.pack_end();
2360       P != PEnd; ++P) {
2361    assert(P->getKind() == TemplateArgument::Type &&"Pack contains a non-type");
2362    assert(P->getAsType().isCanonical() && "Pack contains non-canonical type");
2363  }
2364#endif
2365
2366  llvm::FoldingSetNodeID ID;
2367  SubstTemplateTypeParmPackType::Profile(ID, Parm, ArgPack);
2368  void *InsertPos = 0;
2369  if (SubstTemplateTypeParmPackType *SubstParm
2370        = SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos))
2371    return QualType(SubstParm, 0);
2372
2373  QualType Canon;
2374  if (!Parm->isCanonicalUnqualified()) {
2375    Canon = getCanonicalType(QualType(Parm, 0));
2376    Canon = getSubstTemplateTypeParmPackType(cast<TemplateTypeParmType>(Canon),
2377                                             ArgPack);
2378    SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos);
2379  }
2380
2381  SubstTemplateTypeParmPackType *SubstParm
2382    = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
2383                                                               ArgPack);
2384  Types.push_back(SubstParm);
2385  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2386  return QualType(SubstParm, 0);
2387}
2388
2389/// \brief Retrieve the template type parameter type for a template
2390/// parameter or parameter pack with the given depth, index, and (optionally)
2391/// name.
2392QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
2393                                             bool ParameterPack,
2394                                             TemplateTypeParmDecl *TTPDecl) const {
2395  llvm::FoldingSetNodeID ID;
2396  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, TTPDecl);
2397  void *InsertPos = 0;
2398  TemplateTypeParmType *TypeParm
2399    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2400
2401  if (TypeParm)
2402    return QualType(TypeParm, 0);
2403
2404  if (TTPDecl) {
2405    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
2406    TypeParm = new (*this, TypeAlignment) TemplateTypeParmType(TTPDecl, Canon);
2407
2408    TemplateTypeParmType *TypeCheck
2409      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2410    assert(!TypeCheck && "Template type parameter canonical type broken");
2411    (void)TypeCheck;
2412  } else
2413    TypeParm = new (*this, TypeAlignment)
2414      TemplateTypeParmType(Depth, Index, ParameterPack);
2415
2416  Types.push_back(TypeParm);
2417  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
2418
2419  return QualType(TypeParm, 0);
2420}
2421
2422TypeSourceInfo *
2423ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
2424                                              SourceLocation NameLoc,
2425                                        const TemplateArgumentListInfo &Args,
2426                                              QualType Underlying) const {
2427  assert(!Name.getAsDependentTemplateName() &&
2428         "No dependent template names here!");
2429  QualType TST = getTemplateSpecializationType(Name, Args, Underlying);
2430
2431  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
2432  TemplateSpecializationTypeLoc TL
2433    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
2434  TL.setTemplateKeywordLoc(SourceLocation());
2435  TL.setTemplateNameLoc(NameLoc);
2436  TL.setLAngleLoc(Args.getLAngleLoc());
2437  TL.setRAngleLoc(Args.getRAngleLoc());
2438  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
2439    TL.setArgLocInfo(i, Args[i].getLocInfo());
2440  return DI;
2441}
2442
2443QualType
2444ASTContext::getTemplateSpecializationType(TemplateName Template,
2445                                          const TemplateArgumentListInfo &Args,
2446                                          QualType Underlying) const {
2447  assert(!Template.getAsDependentTemplateName() &&
2448         "No dependent template names here!");
2449
2450  unsigned NumArgs = Args.size();
2451
2452  SmallVector<TemplateArgument, 4> ArgVec;
2453  ArgVec.reserve(NumArgs);
2454  for (unsigned i = 0; i != NumArgs; ++i)
2455    ArgVec.push_back(Args[i].getArgument());
2456
2457  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
2458                                       Underlying);
2459}
2460
2461#ifndef NDEBUG
2462static bool hasAnyPackExpansions(const TemplateArgument *Args,
2463                                 unsigned NumArgs) {
2464  for (unsigned I = 0; I != NumArgs; ++I)
2465    if (Args[I].isPackExpansion())
2466      return true;
2467
2468  return true;
2469}
2470#endif
2471
2472QualType
2473ASTContext::getTemplateSpecializationType(TemplateName Template,
2474                                          const TemplateArgument *Args,
2475                                          unsigned NumArgs,
2476                                          QualType Underlying) const {
2477  assert(!Template.getAsDependentTemplateName() &&
2478         "No dependent template names here!");
2479  // Look through qualified template names.
2480  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2481    Template = TemplateName(QTN->getTemplateDecl());
2482
2483  bool IsTypeAlias =
2484    Template.getAsTemplateDecl() &&
2485    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
2486  QualType CanonType;
2487  if (!Underlying.isNull())
2488    CanonType = getCanonicalType(Underlying);
2489  else {
2490    // We can get here with an alias template when the specialization contains
2491    // a pack expansion that does not match up with a parameter pack.
2492    assert((!IsTypeAlias || hasAnyPackExpansions(Args, NumArgs)) &&
2493           "Caller must compute aliased type");
2494    IsTypeAlias = false;
2495    CanonType = getCanonicalTemplateSpecializationType(Template, Args,
2496                                                       NumArgs);
2497  }
2498
2499  // Allocate the (non-canonical) template specialization type, but don't
2500  // try to unique it: these types typically have location information that
2501  // we don't unique and don't want to lose.
2502  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
2503                       sizeof(TemplateArgument) * NumArgs +
2504                       (IsTypeAlias? sizeof(QualType) : 0),
2505                       TypeAlignment);
2506  TemplateSpecializationType *Spec
2507    = new (Mem) TemplateSpecializationType(Template, Args, NumArgs, CanonType,
2508                                         IsTypeAlias ? Underlying : QualType());
2509
2510  Types.push_back(Spec);
2511  return QualType(Spec, 0);
2512}
2513
2514QualType
2515ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
2516                                                   const TemplateArgument *Args,
2517                                                   unsigned NumArgs) const {
2518  assert(!Template.getAsDependentTemplateName() &&
2519         "No dependent template names here!");
2520
2521  // Look through qualified template names.
2522  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2523    Template = TemplateName(QTN->getTemplateDecl());
2524
2525  // Build the canonical template specialization type.
2526  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
2527  SmallVector<TemplateArgument, 4> CanonArgs;
2528  CanonArgs.reserve(NumArgs);
2529  for (unsigned I = 0; I != NumArgs; ++I)
2530    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
2531
2532  // Determine whether this canonical template specialization type already
2533  // exists.
2534  llvm::FoldingSetNodeID ID;
2535  TemplateSpecializationType::Profile(ID, CanonTemplate,
2536                                      CanonArgs.data(), NumArgs, *this);
2537
2538  void *InsertPos = 0;
2539  TemplateSpecializationType *Spec
2540    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2541
2542  if (!Spec) {
2543    // Allocate a new canonical template specialization type.
2544    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2545                          sizeof(TemplateArgument) * NumArgs),
2546                         TypeAlignment);
2547    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
2548                                                CanonArgs.data(), NumArgs,
2549                                                QualType(), QualType());
2550    Types.push_back(Spec);
2551    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
2552  }
2553
2554  assert(Spec->isDependentType() &&
2555         "Non-dependent template-id type must have a canonical type");
2556  return QualType(Spec, 0);
2557}
2558
2559QualType
2560ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
2561                              NestedNameSpecifier *NNS,
2562                              QualType NamedType) const {
2563  llvm::FoldingSetNodeID ID;
2564  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2565
2566  void *InsertPos = 0;
2567  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2568  if (T)
2569    return QualType(T, 0);
2570
2571  QualType Canon = NamedType;
2572  if (!Canon.isCanonical()) {
2573    Canon = getCanonicalType(NamedType);
2574    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2575    assert(!CheckT && "Elaborated canonical type broken");
2576    (void)CheckT;
2577  }
2578
2579  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2580  Types.push_back(T);
2581  ElaboratedTypes.InsertNode(T, InsertPos);
2582  return QualType(T, 0);
2583}
2584
2585QualType
2586ASTContext::getParenType(QualType InnerType) const {
2587  llvm::FoldingSetNodeID ID;
2588  ParenType::Profile(ID, InnerType);
2589
2590  void *InsertPos = 0;
2591  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2592  if (T)
2593    return QualType(T, 0);
2594
2595  QualType Canon = InnerType;
2596  if (!Canon.isCanonical()) {
2597    Canon = getCanonicalType(InnerType);
2598    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2599    assert(!CheckT && "Paren canonical type broken");
2600    (void)CheckT;
2601  }
2602
2603  T = new (*this) ParenType(InnerType, Canon);
2604  Types.push_back(T);
2605  ParenTypes.InsertNode(T, InsertPos);
2606  return QualType(T, 0);
2607}
2608
2609QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2610                                          NestedNameSpecifier *NNS,
2611                                          const IdentifierInfo *Name,
2612                                          QualType Canon) const {
2613  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2614
2615  if (Canon.isNull()) {
2616    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2617    ElaboratedTypeKeyword CanonKeyword = Keyword;
2618    if (Keyword == ETK_None)
2619      CanonKeyword = ETK_Typename;
2620
2621    if (CanonNNS != NNS || CanonKeyword != Keyword)
2622      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2623  }
2624
2625  llvm::FoldingSetNodeID ID;
2626  DependentNameType::Profile(ID, Keyword, NNS, Name);
2627
2628  void *InsertPos = 0;
2629  DependentNameType *T
2630    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2631  if (T)
2632    return QualType(T, 0);
2633
2634  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2635  Types.push_back(T);
2636  DependentNameTypes.InsertNode(T, InsertPos);
2637  return QualType(T, 0);
2638}
2639
2640QualType
2641ASTContext::getDependentTemplateSpecializationType(
2642                                 ElaboratedTypeKeyword Keyword,
2643                                 NestedNameSpecifier *NNS,
2644                                 const IdentifierInfo *Name,
2645                                 const TemplateArgumentListInfo &Args) const {
2646  // TODO: avoid this copy
2647  SmallVector<TemplateArgument, 16> ArgCopy;
2648  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2649    ArgCopy.push_back(Args[I].getArgument());
2650  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2651                                                ArgCopy.size(),
2652                                                ArgCopy.data());
2653}
2654
2655QualType
2656ASTContext::getDependentTemplateSpecializationType(
2657                                 ElaboratedTypeKeyword Keyword,
2658                                 NestedNameSpecifier *NNS,
2659                                 const IdentifierInfo *Name,
2660                                 unsigned NumArgs,
2661                                 const TemplateArgument *Args) const {
2662  assert((!NNS || NNS->isDependent()) &&
2663         "nested-name-specifier must be dependent");
2664
2665  llvm::FoldingSetNodeID ID;
2666  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2667                                               Name, NumArgs, Args);
2668
2669  void *InsertPos = 0;
2670  DependentTemplateSpecializationType *T
2671    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2672  if (T)
2673    return QualType(T, 0);
2674
2675  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2676
2677  ElaboratedTypeKeyword CanonKeyword = Keyword;
2678  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2679
2680  bool AnyNonCanonArgs = false;
2681  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2682  for (unsigned I = 0; I != NumArgs; ++I) {
2683    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2684    if (!CanonArgs[I].structurallyEquals(Args[I]))
2685      AnyNonCanonArgs = true;
2686  }
2687
2688  QualType Canon;
2689  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2690    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2691                                                   Name, NumArgs,
2692                                                   CanonArgs.data());
2693
2694    // Find the insert position again.
2695    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2696  }
2697
2698  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2699                        sizeof(TemplateArgument) * NumArgs),
2700                       TypeAlignment);
2701  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2702                                                    Name, NumArgs, Args, Canon);
2703  Types.push_back(T);
2704  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2705  return QualType(T, 0);
2706}
2707
2708QualType ASTContext::getPackExpansionType(QualType Pattern,
2709                                      llvm::Optional<unsigned> NumExpansions) {
2710  llvm::FoldingSetNodeID ID;
2711  PackExpansionType::Profile(ID, Pattern, NumExpansions);
2712
2713  assert(Pattern->containsUnexpandedParameterPack() &&
2714         "Pack expansions must expand one or more parameter packs");
2715  void *InsertPos = 0;
2716  PackExpansionType *T
2717    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2718  if (T)
2719    return QualType(T, 0);
2720
2721  QualType Canon;
2722  if (!Pattern.isCanonical()) {
2723    Canon = getPackExpansionType(getCanonicalType(Pattern), NumExpansions);
2724
2725    // Find the insert position again.
2726    PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2727  }
2728
2729  T = new (*this) PackExpansionType(Pattern, Canon, NumExpansions);
2730  Types.push_back(T);
2731  PackExpansionTypes.InsertNode(T, InsertPos);
2732  return QualType(T, 0);
2733}
2734
2735/// CmpProtocolNames - Comparison predicate for sorting protocols
2736/// alphabetically.
2737static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2738                            const ObjCProtocolDecl *RHS) {
2739  return LHS->getDeclName() < RHS->getDeclName();
2740}
2741
2742static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2743                                unsigned NumProtocols) {
2744  if (NumProtocols == 0) return true;
2745
2746  if (Protocols[0]->getCanonicalDecl() != Protocols[0])
2747    return false;
2748
2749  for (unsigned i = 1; i != NumProtocols; ++i)
2750    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]) ||
2751        Protocols[i]->getCanonicalDecl() != Protocols[i])
2752      return false;
2753  return true;
2754}
2755
2756static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2757                                   unsigned &NumProtocols) {
2758  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2759
2760  // Sort protocols, keyed by name.
2761  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2762
2763  // Canonicalize.
2764  for (unsigned I = 0, N = NumProtocols; I != N; ++I)
2765    Protocols[I] = Protocols[I]->getCanonicalDecl();
2766
2767  // Remove duplicates.
2768  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2769  NumProtocols = ProtocolsEnd-Protocols;
2770}
2771
2772QualType ASTContext::getObjCObjectType(QualType BaseType,
2773                                       ObjCProtocolDecl * const *Protocols,
2774                                       unsigned NumProtocols) const {
2775  // If the base type is an interface and there aren't any protocols
2776  // to add, then the interface type will do just fine.
2777  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2778    return BaseType;
2779
2780  // Look in the folding set for an existing type.
2781  llvm::FoldingSetNodeID ID;
2782  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2783  void *InsertPos = 0;
2784  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2785    return QualType(QT, 0);
2786
2787  // Build the canonical type, which has the canonical base type and
2788  // a sorted-and-uniqued list of protocols.
2789  QualType Canonical;
2790  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2791  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2792    if (!ProtocolsSorted) {
2793      SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2794                                                     Protocols + NumProtocols);
2795      unsigned UniqueCount = NumProtocols;
2796
2797      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2798      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2799                                    &Sorted[0], UniqueCount);
2800    } else {
2801      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2802                                    Protocols, NumProtocols);
2803    }
2804
2805    // Regenerate InsertPos.
2806    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2807  }
2808
2809  unsigned Size = sizeof(ObjCObjectTypeImpl);
2810  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2811  void *Mem = Allocate(Size, TypeAlignment);
2812  ObjCObjectTypeImpl *T =
2813    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2814
2815  Types.push_back(T);
2816  ObjCObjectTypes.InsertNode(T, InsertPos);
2817  return QualType(T, 0);
2818}
2819
2820/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2821/// the given object type.
2822QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
2823  llvm::FoldingSetNodeID ID;
2824  ObjCObjectPointerType::Profile(ID, ObjectT);
2825
2826  void *InsertPos = 0;
2827  if (ObjCObjectPointerType *QT =
2828              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2829    return QualType(QT, 0);
2830
2831  // Find the canonical object type.
2832  QualType Canonical;
2833  if (!ObjectT.isCanonical()) {
2834    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2835
2836    // Regenerate InsertPos.
2837    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2838  }
2839
2840  // No match.
2841  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2842  ObjCObjectPointerType *QType =
2843    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2844
2845  Types.push_back(QType);
2846  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2847  return QualType(QType, 0);
2848}
2849
2850/// getObjCInterfaceType - Return the unique reference to the type for the
2851/// specified ObjC interface decl. The list of protocols is optional.
2852QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
2853                                          ObjCInterfaceDecl *PrevDecl) const {
2854  if (Decl->TypeForDecl)
2855    return QualType(Decl->TypeForDecl, 0);
2856
2857  if (PrevDecl) {
2858    assert(PrevDecl->TypeForDecl && "previous decl has no TypeForDecl");
2859    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2860    return QualType(PrevDecl->TypeForDecl, 0);
2861  }
2862
2863  // Prefer the definition, if there is one.
2864  if (const ObjCInterfaceDecl *Def = Decl->getDefinition())
2865    Decl = Def;
2866
2867  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2868  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2869  Decl->TypeForDecl = T;
2870  Types.push_back(T);
2871  return QualType(T, 0);
2872}
2873
2874/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2875/// TypeOfExprType AST's (since expression's are never shared). For example,
2876/// multiple declarations that refer to "typeof(x)" all contain different
2877/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2878/// on canonical type's (which are always unique).
2879QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
2880  TypeOfExprType *toe;
2881  if (tofExpr->isTypeDependent()) {
2882    llvm::FoldingSetNodeID ID;
2883    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2884
2885    void *InsertPos = 0;
2886    DependentTypeOfExprType *Canon
2887      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2888    if (Canon) {
2889      // We already have a "canonical" version of an identical, dependent
2890      // typeof(expr) type. Use that as our canonical type.
2891      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2892                                          QualType((TypeOfExprType*)Canon, 0));
2893    } else {
2894      // Build a new, canonical typeof(expr) type.
2895      Canon
2896        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2897      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2898      toe = Canon;
2899    }
2900  } else {
2901    QualType Canonical = getCanonicalType(tofExpr->getType());
2902    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2903  }
2904  Types.push_back(toe);
2905  return QualType(toe, 0);
2906}
2907
2908/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2909/// TypeOfType AST's. The only motivation to unique these nodes would be
2910/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2911/// an issue. This doesn't effect the type checker, since it operates
2912/// on canonical type's (which are always unique).
2913QualType ASTContext::getTypeOfType(QualType tofType) const {
2914  QualType Canonical = getCanonicalType(tofType);
2915  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2916  Types.push_back(tot);
2917  return QualType(tot, 0);
2918}
2919
2920/// getDecltypeForExpr - Given an expr, will return the decltype for that
2921/// expression, according to the rules in C++0x [dcl.type.simple]p4
2922static QualType getDecltypeForExpr(const Expr *e, const ASTContext &Context) {
2923  if (e->isTypeDependent())
2924    return Context.DependentTy;
2925
2926  // If e is an id expression or a class member access, decltype(e) is defined
2927  // as the type of the entity named by e.
2928  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2929    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2930      return VD->getType();
2931  }
2932  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2933    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2934      return FD->getType();
2935  }
2936  // If e is a function call or an invocation of an overloaded operator,
2937  // (parentheses around e are ignored), decltype(e) is defined as the
2938  // return type of that function.
2939  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2940    return CE->getCallReturnType();
2941
2942  QualType T = e->getType();
2943
2944  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2945  // defined as T&, otherwise decltype(e) is defined as T.
2946  if (e->isLValue())
2947    T = Context.getLValueReferenceType(T);
2948
2949  return T;
2950}
2951
2952/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2953/// DecltypeType AST's. The only motivation to unique these nodes would be
2954/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2955/// an issue. This doesn't effect the type checker, since it operates
2956/// on canonical types (which are always unique).
2957QualType ASTContext::getDecltypeType(Expr *e) const {
2958  DecltypeType *dt;
2959
2960  // C++0x [temp.type]p2:
2961  //   If an expression e involves a template parameter, decltype(e) denotes a
2962  //   unique dependent type. Two such decltype-specifiers refer to the same
2963  //   type only if their expressions are equivalent (14.5.6.1).
2964  if (e->isInstantiationDependent()) {
2965    llvm::FoldingSetNodeID ID;
2966    DependentDecltypeType::Profile(ID, *this, e);
2967
2968    void *InsertPos = 0;
2969    DependentDecltypeType *Canon
2970      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2971    if (Canon) {
2972      // We already have a "canonical" version of an equivalent, dependent
2973      // decltype type. Use that as our canonical type.
2974      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2975                                       QualType((DecltypeType*)Canon, 0));
2976    } else {
2977      // Build a new, canonical typeof(expr) type.
2978      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2979      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2980      dt = Canon;
2981    }
2982  } else {
2983    QualType T = getDecltypeForExpr(e, *this);
2984    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2985  }
2986  Types.push_back(dt);
2987  return QualType(dt, 0);
2988}
2989
2990/// getUnaryTransformationType - We don't unique these, since the memory
2991/// savings are minimal and these are rare.
2992QualType ASTContext::getUnaryTransformType(QualType BaseType,
2993                                           QualType UnderlyingType,
2994                                           UnaryTransformType::UTTKind Kind)
2995    const {
2996  UnaryTransformType *Ty =
2997    new (*this, TypeAlignment) UnaryTransformType (BaseType, UnderlyingType,
2998                                                   Kind,
2999                                 UnderlyingType->isDependentType() ?
3000                                    QualType() : UnderlyingType);
3001  Types.push_back(Ty);
3002  return QualType(Ty, 0);
3003}
3004
3005/// getAutoType - We only unique auto types after they've been deduced.
3006QualType ASTContext::getAutoType(QualType DeducedType) const {
3007  void *InsertPos = 0;
3008  if (!DeducedType.isNull()) {
3009    // Look in the folding set for an existing type.
3010    llvm::FoldingSetNodeID ID;
3011    AutoType::Profile(ID, DeducedType);
3012    if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
3013      return QualType(AT, 0);
3014  }
3015
3016  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType);
3017  Types.push_back(AT);
3018  if (InsertPos)
3019    AutoTypes.InsertNode(AT, InsertPos);
3020  return QualType(AT, 0);
3021}
3022
3023/// getAtomicType - Return the uniqued reference to the atomic type for
3024/// the given value type.
3025QualType ASTContext::getAtomicType(QualType T) const {
3026  // Unique pointers, to guarantee there is only one pointer of a particular
3027  // structure.
3028  llvm::FoldingSetNodeID ID;
3029  AtomicType::Profile(ID, T);
3030
3031  void *InsertPos = 0;
3032  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
3033    return QualType(AT, 0);
3034
3035  // If the atomic value type isn't canonical, this won't be a canonical type
3036  // either, so fill in the canonical type field.
3037  QualType Canonical;
3038  if (!T.isCanonical()) {
3039    Canonical = getAtomicType(getCanonicalType(T));
3040
3041    // Get the new insert position for the node we care about.
3042    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
3043    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
3044  }
3045  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
3046  Types.push_back(New);
3047  AtomicTypes.InsertNode(New, InsertPos);
3048  return QualType(New, 0);
3049}
3050
3051/// getAutoDeductType - Get type pattern for deducing against 'auto'.
3052QualType ASTContext::getAutoDeductType() const {
3053  if (AutoDeductTy.isNull())
3054    AutoDeductTy = getAutoType(QualType());
3055  assert(!AutoDeductTy.isNull() && "can't build 'auto' pattern");
3056  return AutoDeductTy;
3057}
3058
3059/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
3060QualType ASTContext::getAutoRRefDeductType() const {
3061  if (AutoRRefDeductTy.isNull())
3062    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
3063  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
3064  return AutoRRefDeductTy;
3065}
3066
3067/// getTagDeclType - Return the unique reference to the type for the
3068/// specified TagDecl (struct/union/class/enum) decl.
3069QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
3070  assert (Decl);
3071  // FIXME: What is the design on getTagDeclType when it requires casting
3072  // away const?  mutable?
3073  return getTypeDeclType(const_cast<TagDecl*>(Decl));
3074}
3075
3076/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
3077/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
3078/// needs to agree with the definition in <stddef.h>.
3079CanQualType ASTContext::getSizeType() const {
3080  return getFromTargetType(Target->getSizeType());
3081}
3082
3083/// getIntMaxType - Return the unique type for "intmax_t" (C99 7.18.1.5).
3084CanQualType ASTContext::getIntMaxType() const {
3085  return getFromTargetType(Target->getIntMaxType());
3086}
3087
3088/// getUIntMaxType - Return the unique type for "uintmax_t" (C99 7.18.1.5).
3089CanQualType ASTContext::getUIntMaxType() const {
3090  return getFromTargetType(Target->getUIntMaxType());
3091}
3092
3093/// getSignedWCharType - Return the type of "signed wchar_t".
3094/// Used when in C++, as a GCC extension.
3095QualType ASTContext::getSignedWCharType() const {
3096  // FIXME: derive from "Target" ?
3097  return WCharTy;
3098}
3099
3100/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
3101/// Used when in C++, as a GCC extension.
3102QualType ASTContext::getUnsignedWCharType() const {
3103  // FIXME: derive from "Target" ?
3104  return UnsignedIntTy;
3105}
3106
3107/// getPointerDiffType - Return the unique type for "ptrdiff_t" (C99 7.17)
3108/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
3109QualType ASTContext::getPointerDiffType() const {
3110  return getFromTargetType(Target->getPtrDiffType(0));
3111}
3112
3113//===----------------------------------------------------------------------===//
3114//                              Type Operators
3115//===----------------------------------------------------------------------===//
3116
3117CanQualType ASTContext::getCanonicalParamType(QualType T) const {
3118  // Push qualifiers into arrays, and then discard any remaining
3119  // qualifiers.
3120  T = getCanonicalType(T);
3121  T = getVariableArrayDecayedType(T);
3122  const Type *Ty = T.getTypePtr();
3123  QualType Result;
3124  if (isa<ArrayType>(Ty)) {
3125    Result = getArrayDecayedType(QualType(Ty,0));
3126  } else if (isa<FunctionType>(Ty)) {
3127    Result = getPointerType(QualType(Ty, 0));
3128  } else {
3129    Result = QualType(Ty, 0);
3130  }
3131
3132  return CanQualType::CreateUnsafe(Result);
3133}
3134
3135QualType ASTContext::getUnqualifiedArrayType(QualType type,
3136                                             Qualifiers &quals) {
3137  SplitQualType splitType = type.getSplitUnqualifiedType();
3138
3139  // FIXME: getSplitUnqualifiedType() actually walks all the way to
3140  // the unqualified desugared type and then drops it on the floor.
3141  // We then have to strip that sugar back off with
3142  // getUnqualifiedDesugaredType(), which is silly.
3143  const ArrayType *AT =
3144    dyn_cast<ArrayType>(splitType.first->getUnqualifiedDesugaredType());
3145
3146  // If we don't have an array, just use the results in splitType.
3147  if (!AT) {
3148    quals = splitType.second;
3149    return QualType(splitType.first, 0);
3150  }
3151
3152  // Otherwise, recurse on the array's element type.
3153  QualType elementType = AT->getElementType();
3154  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
3155
3156  // If that didn't change the element type, AT has no qualifiers, so we
3157  // can just use the results in splitType.
3158  if (elementType == unqualElementType) {
3159    assert(quals.empty()); // from the recursive call
3160    quals = splitType.second;
3161    return QualType(splitType.first, 0);
3162  }
3163
3164  // Otherwise, add in the qualifiers from the outermost type, then
3165  // build the type back up.
3166  quals.addConsistentQualifiers(splitType.second);
3167
3168  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
3169    return getConstantArrayType(unqualElementType, CAT->getSize(),
3170                                CAT->getSizeModifier(), 0);
3171  }
3172
3173  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
3174    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
3175  }
3176
3177  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
3178    return getVariableArrayType(unqualElementType,
3179                                VAT->getSizeExpr(),
3180                                VAT->getSizeModifier(),
3181                                VAT->getIndexTypeCVRQualifiers(),
3182                                VAT->getBracketsRange());
3183  }
3184
3185  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
3186  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
3187                                    DSAT->getSizeModifier(), 0,
3188                                    SourceRange());
3189}
3190
3191/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
3192/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
3193/// they point to and return true. If T1 and T2 aren't pointer types
3194/// or pointer-to-member types, or if they are not similar at this
3195/// level, returns false and leaves T1 and T2 unchanged. Top-level
3196/// qualifiers on T1 and T2 are ignored. This function will typically
3197/// be called in a loop that successively "unwraps" pointer and
3198/// pointer-to-member types to compare them at each level.
3199bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
3200  const PointerType *T1PtrType = T1->getAs<PointerType>(),
3201                    *T2PtrType = T2->getAs<PointerType>();
3202  if (T1PtrType && T2PtrType) {
3203    T1 = T1PtrType->getPointeeType();
3204    T2 = T2PtrType->getPointeeType();
3205    return true;
3206  }
3207
3208  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
3209                          *T2MPType = T2->getAs<MemberPointerType>();
3210  if (T1MPType && T2MPType &&
3211      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
3212                             QualType(T2MPType->getClass(), 0))) {
3213    T1 = T1MPType->getPointeeType();
3214    T2 = T2MPType->getPointeeType();
3215    return true;
3216  }
3217
3218  if (getLangOptions().ObjC1) {
3219    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
3220                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
3221    if (T1OPType && T2OPType) {
3222      T1 = T1OPType->getPointeeType();
3223      T2 = T2OPType->getPointeeType();
3224      return true;
3225    }
3226  }
3227
3228  // FIXME: Block pointers, too?
3229
3230  return false;
3231}
3232
3233DeclarationNameInfo
3234ASTContext::getNameForTemplate(TemplateName Name,
3235                               SourceLocation NameLoc) const {
3236  switch (Name.getKind()) {
3237  case TemplateName::QualifiedTemplate:
3238  case TemplateName::Template:
3239    // DNInfo work in progress: CHECKME: what about DNLoc?
3240    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
3241                               NameLoc);
3242
3243  case TemplateName::OverloadedTemplate: {
3244    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
3245    // DNInfo work in progress: CHECKME: what about DNLoc?
3246    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
3247  }
3248
3249  case TemplateName::DependentTemplate: {
3250    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3251    DeclarationName DName;
3252    if (DTN->isIdentifier()) {
3253      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
3254      return DeclarationNameInfo(DName, NameLoc);
3255    } else {
3256      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
3257      // DNInfo work in progress: FIXME: source locations?
3258      DeclarationNameLoc DNLoc;
3259      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
3260      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
3261      return DeclarationNameInfo(DName, NameLoc, DNLoc);
3262    }
3263  }
3264
3265  case TemplateName::SubstTemplateTemplateParm: {
3266    SubstTemplateTemplateParmStorage *subst
3267      = Name.getAsSubstTemplateTemplateParm();
3268    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
3269                               NameLoc);
3270  }
3271
3272  case TemplateName::SubstTemplateTemplateParmPack: {
3273    SubstTemplateTemplateParmPackStorage *subst
3274      = Name.getAsSubstTemplateTemplateParmPack();
3275    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
3276                               NameLoc);
3277  }
3278  }
3279
3280  llvm_unreachable("bad template name kind!");
3281}
3282
3283TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
3284  switch (Name.getKind()) {
3285  case TemplateName::QualifiedTemplate:
3286  case TemplateName::Template: {
3287    TemplateDecl *Template = Name.getAsTemplateDecl();
3288    if (TemplateTemplateParmDecl *TTP
3289          = dyn_cast<TemplateTemplateParmDecl>(Template))
3290      Template = getCanonicalTemplateTemplateParmDecl(TTP);
3291
3292    // The canonical template name is the canonical template declaration.
3293    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
3294  }
3295
3296  case TemplateName::OverloadedTemplate:
3297    llvm_unreachable("cannot canonicalize overloaded template");
3298
3299  case TemplateName::DependentTemplate: {
3300    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3301    assert(DTN && "Non-dependent template names must refer to template decls.");
3302    return DTN->CanonicalTemplateName;
3303  }
3304
3305  case TemplateName::SubstTemplateTemplateParm: {
3306    SubstTemplateTemplateParmStorage *subst
3307      = Name.getAsSubstTemplateTemplateParm();
3308    return getCanonicalTemplateName(subst->getReplacement());
3309  }
3310
3311  case TemplateName::SubstTemplateTemplateParmPack: {
3312    SubstTemplateTemplateParmPackStorage *subst
3313                                  = Name.getAsSubstTemplateTemplateParmPack();
3314    TemplateTemplateParmDecl *canonParameter
3315      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
3316    TemplateArgument canonArgPack
3317      = getCanonicalTemplateArgument(subst->getArgumentPack());
3318    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
3319  }
3320  }
3321
3322  llvm_unreachable("bad template name!");
3323}
3324
3325bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
3326  X = getCanonicalTemplateName(X);
3327  Y = getCanonicalTemplateName(Y);
3328  return X.getAsVoidPointer() == Y.getAsVoidPointer();
3329}
3330
3331TemplateArgument
3332ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
3333  switch (Arg.getKind()) {
3334    case TemplateArgument::Null:
3335      return Arg;
3336
3337    case TemplateArgument::Expression:
3338      return Arg;
3339
3340    case TemplateArgument::Declaration:
3341      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
3342
3343    case TemplateArgument::Template:
3344      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
3345
3346    case TemplateArgument::TemplateExpansion:
3347      return TemplateArgument(getCanonicalTemplateName(
3348                                         Arg.getAsTemplateOrTemplatePattern()),
3349                              Arg.getNumTemplateExpansions());
3350
3351    case TemplateArgument::Integral:
3352      return TemplateArgument(*Arg.getAsIntegral(),
3353                              getCanonicalType(Arg.getIntegralType()));
3354
3355    case TemplateArgument::Type:
3356      return TemplateArgument(getCanonicalType(Arg.getAsType()));
3357
3358    case TemplateArgument::Pack: {
3359      if (Arg.pack_size() == 0)
3360        return Arg;
3361
3362      TemplateArgument *CanonArgs
3363        = new (*this) TemplateArgument[Arg.pack_size()];
3364      unsigned Idx = 0;
3365      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
3366                                        AEnd = Arg.pack_end();
3367           A != AEnd; (void)++A, ++Idx)
3368        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
3369
3370      return TemplateArgument(CanonArgs, Arg.pack_size());
3371    }
3372  }
3373
3374  // Silence GCC warning
3375  llvm_unreachable("Unhandled template argument kind");
3376}
3377
3378NestedNameSpecifier *
3379ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
3380  if (!NNS)
3381    return 0;
3382
3383  switch (NNS->getKind()) {
3384  case NestedNameSpecifier::Identifier:
3385    // Canonicalize the prefix but keep the identifier the same.
3386    return NestedNameSpecifier::Create(*this,
3387                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
3388                                       NNS->getAsIdentifier());
3389
3390  case NestedNameSpecifier::Namespace:
3391    // A namespace is canonical; build a nested-name-specifier with
3392    // this namespace and no prefix.
3393    return NestedNameSpecifier::Create(*this, 0,
3394                                 NNS->getAsNamespace()->getOriginalNamespace());
3395
3396  case NestedNameSpecifier::NamespaceAlias:
3397    // A namespace is canonical; build a nested-name-specifier with
3398    // this namespace and no prefix.
3399    return NestedNameSpecifier::Create(*this, 0,
3400                                    NNS->getAsNamespaceAlias()->getNamespace()
3401                                                      ->getOriginalNamespace());
3402
3403  case NestedNameSpecifier::TypeSpec:
3404  case NestedNameSpecifier::TypeSpecWithTemplate: {
3405    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
3406
3407    // If we have some kind of dependent-named type (e.g., "typename T::type"),
3408    // break it apart into its prefix and identifier, then reconsititute those
3409    // as the canonical nested-name-specifier. This is required to canonicalize
3410    // a dependent nested-name-specifier involving typedefs of dependent-name
3411    // types, e.g.,
3412    //   typedef typename T::type T1;
3413    //   typedef typename T1::type T2;
3414    if (const DependentNameType *DNT = T->getAs<DependentNameType>()) {
3415      NestedNameSpecifier *Prefix
3416        = getCanonicalNestedNameSpecifier(DNT->getQualifier());
3417      return NestedNameSpecifier::Create(*this, Prefix,
3418                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
3419    }
3420
3421    // Do the same thing as above, but with dependent-named specializations.
3422    if (const DependentTemplateSpecializationType *DTST
3423          = T->getAs<DependentTemplateSpecializationType>()) {
3424      NestedNameSpecifier *Prefix
3425        = getCanonicalNestedNameSpecifier(DTST->getQualifier());
3426
3427      T = getDependentTemplateSpecializationType(DTST->getKeyword(),
3428                                                 Prefix, DTST->getIdentifier(),
3429                                                 DTST->getNumArgs(),
3430                                                 DTST->getArgs());
3431      T = getCanonicalType(T);
3432    }
3433
3434    return NestedNameSpecifier::Create(*this, 0, false,
3435                                       const_cast<Type*>(T.getTypePtr()));
3436  }
3437
3438  case NestedNameSpecifier::Global:
3439    // The global specifier is canonical and unique.
3440    return NNS;
3441  }
3442
3443  llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
3444}
3445
3446
3447const ArrayType *ASTContext::getAsArrayType(QualType T) const {
3448  // Handle the non-qualified case efficiently.
3449  if (!T.hasLocalQualifiers()) {
3450    // Handle the common positive case fast.
3451    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
3452      return AT;
3453  }
3454
3455  // Handle the common negative case fast.
3456  if (!isa<ArrayType>(T.getCanonicalType()))
3457    return 0;
3458
3459  // Apply any qualifiers from the array type to the element type.  This
3460  // implements C99 6.7.3p8: "If the specification of an array type includes
3461  // any type qualifiers, the element type is so qualified, not the array type."
3462
3463  // If we get here, we either have type qualifiers on the type, or we have
3464  // sugar such as a typedef in the way.  If we have type qualifiers on the type
3465  // we must propagate them down into the element type.
3466
3467  SplitQualType split = T.getSplitDesugaredType();
3468  Qualifiers qs = split.second;
3469
3470  // If we have a simple case, just return now.
3471  const ArrayType *ATy = dyn_cast<ArrayType>(split.first);
3472  if (ATy == 0 || qs.empty())
3473    return ATy;
3474
3475  // Otherwise, we have an array and we have qualifiers on it.  Push the
3476  // qualifiers into the array element type and return a new array type.
3477  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
3478
3479  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
3480    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
3481                                                CAT->getSizeModifier(),
3482                                           CAT->getIndexTypeCVRQualifiers()));
3483  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
3484    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
3485                                                  IAT->getSizeModifier(),
3486                                           IAT->getIndexTypeCVRQualifiers()));
3487
3488  if (const DependentSizedArrayType *DSAT
3489        = dyn_cast<DependentSizedArrayType>(ATy))
3490    return cast<ArrayType>(
3491                     getDependentSizedArrayType(NewEltTy,
3492                                                DSAT->getSizeExpr(),
3493                                                DSAT->getSizeModifier(),
3494                                              DSAT->getIndexTypeCVRQualifiers(),
3495                                                DSAT->getBracketsRange()));
3496
3497  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
3498  return cast<ArrayType>(getVariableArrayType(NewEltTy,
3499                                              VAT->getSizeExpr(),
3500                                              VAT->getSizeModifier(),
3501                                              VAT->getIndexTypeCVRQualifiers(),
3502                                              VAT->getBracketsRange()));
3503}
3504
3505QualType ASTContext::getAdjustedParameterType(QualType T) {
3506  // C99 6.7.5.3p7:
3507  //   A declaration of a parameter as "array of type" shall be
3508  //   adjusted to "qualified pointer to type", where the type
3509  //   qualifiers (if any) are those specified within the [ and ] of
3510  //   the array type derivation.
3511  if (T->isArrayType())
3512    return getArrayDecayedType(T);
3513
3514  // C99 6.7.5.3p8:
3515  //   A declaration of a parameter as "function returning type"
3516  //   shall be adjusted to "pointer to function returning type", as
3517  //   in 6.3.2.1.
3518  if (T->isFunctionType())
3519    return getPointerType(T);
3520
3521  return T;
3522}
3523
3524QualType ASTContext::getSignatureParameterType(QualType T) {
3525  T = getVariableArrayDecayedType(T);
3526  T = getAdjustedParameterType(T);
3527  return T.getUnqualifiedType();
3528}
3529
3530/// getArrayDecayedType - Return the properly qualified result of decaying the
3531/// specified array type to a pointer.  This operation is non-trivial when
3532/// handling typedefs etc.  The canonical type of "T" must be an array type,
3533/// this returns a pointer to a properly qualified element of the array.
3534///
3535/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
3536QualType ASTContext::getArrayDecayedType(QualType Ty) const {
3537  // Get the element type with 'getAsArrayType' so that we don't lose any
3538  // typedefs in the element type of the array.  This also handles propagation
3539  // of type qualifiers from the array type into the element type if present
3540  // (C99 6.7.3p8).
3541  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
3542  assert(PrettyArrayType && "Not an array type!");
3543
3544  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
3545
3546  // int x[restrict 4] ->  int *restrict
3547  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
3548}
3549
3550QualType ASTContext::getBaseElementType(const ArrayType *array) const {
3551  return getBaseElementType(array->getElementType());
3552}
3553
3554QualType ASTContext::getBaseElementType(QualType type) const {
3555  Qualifiers qs;
3556  while (true) {
3557    SplitQualType split = type.getSplitDesugaredType();
3558    const ArrayType *array = split.first->getAsArrayTypeUnsafe();
3559    if (!array) break;
3560
3561    type = array->getElementType();
3562    qs.addConsistentQualifiers(split.second);
3563  }
3564
3565  return getQualifiedType(type, qs);
3566}
3567
3568/// getConstantArrayElementCount - Returns number of constant array elements.
3569uint64_t
3570ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
3571  uint64_t ElementCount = 1;
3572  do {
3573    ElementCount *= CA->getSize().getZExtValue();
3574    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
3575  } while (CA);
3576  return ElementCount;
3577}
3578
3579/// getFloatingRank - Return a relative rank for floating point types.
3580/// This routine will assert if passed a built-in type that isn't a float.
3581static FloatingRank getFloatingRank(QualType T) {
3582  if (const ComplexType *CT = T->getAs<ComplexType>())
3583    return getFloatingRank(CT->getElementType());
3584
3585  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
3586  switch (T->getAs<BuiltinType>()->getKind()) {
3587  default: llvm_unreachable("getFloatingRank(): not a floating type");
3588  case BuiltinType::Half:       return HalfRank;
3589  case BuiltinType::Float:      return FloatRank;
3590  case BuiltinType::Double:     return DoubleRank;
3591  case BuiltinType::LongDouble: return LongDoubleRank;
3592  }
3593}
3594
3595/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
3596/// point or a complex type (based on typeDomain/typeSize).
3597/// 'typeDomain' is a real floating point or complex type.
3598/// 'typeSize' is a real floating point or complex type.
3599QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
3600                                                       QualType Domain) const {
3601  FloatingRank EltRank = getFloatingRank(Size);
3602  if (Domain->isComplexType()) {
3603    switch (EltRank) {
3604    case HalfRank: llvm_unreachable("Complex half is not supported");
3605    case FloatRank:      return FloatComplexTy;
3606    case DoubleRank:     return DoubleComplexTy;
3607    case LongDoubleRank: return LongDoubleComplexTy;
3608    }
3609  }
3610
3611  assert(Domain->isRealFloatingType() && "Unknown domain!");
3612  switch (EltRank) {
3613  case HalfRank: llvm_unreachable("Half ranks are not valid here");
3614  case FloatRank:      return FloatTy;
3615  case DoubleRank:     return DoubleTy;
3616  case LongDoubleRank: return LongDoubleTy;
3617  }
3618  llvm_unreachable("getFloatingRank(): illegal value for rank");
3619}
3620
3621/// getFloatingTypeOrder - Compare the rank of the two specified floating
3622/// point types, ignoring the domain of the type (i.e. 'double' ==
3623/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3624/// LHS < RHS, return -1.
3625int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
3626  FloatingRank LHSR = getFloatingRank(LHS);
3627  FloatingRank RHSR = getFloatingRank(RHS);
3628
3629  if (LHSR == RHSR)
3630    return 0;
3631  if (LHSR > RHSR)
3632    return 1;
3633  return -1;
3634}
3635
3636/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
3637/// routine will assert if passed a built-in type that isn't an integer or enum,
3638/// or if it is not canonicalized.
3639unsigned ASTContext::getIntegerRank(const Type *T) const {
3640  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
3641
3642  switch (cast<BuiltinType>(T)->getKind()) {
3643  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
3644  case BuiltinType::Bool:
3645    return 1 + (getIntWidth(BoolTy) << 3);
3646  case BuiltinType::Char_S:
3647  case BuiltinType::Char_U:
3648  case BuiltinType::SChar:
3649  case BuiltinType::UChar:
3650    return 2 + (getIntWidth(CharTy) << 3);
3651  case BuiltinType::Short:
3652  case BuiltinType::UShort:
3653    return 3 + (getIntWidth(ShortTy) << 3);
3654  case BuiltinType::Int:
3655  case BuiltinType::UInt:
3656    return 4 + (getIntWidth(IntTy) << 3);
3657  case BuiltinType::Long:
3658  case BuiltinType::ULong:
3659    return 5 + (getIntWidth(LongTy) << 3);
3660  case BuiltinType::LongLong:
3661  case BuiltinType::ULongLong:
3662    return 6 + (getIntWidth(LongLongTy) << 3);
3663  case BuiltinType::Int128:
3664  case BuiltinType::UInt128:
3665    return 7 + (getIntWidth(Int128Ty) << 3);
3666  }
3667}
3668
3669/// \brief Whether this is a promotable bitfield reference according
3670/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
3671///
3672/// \returns the type this bit-field will promote to, or NULL if no
3673/// promotion occurs.
3674QualType ASTContext::isPromotableBitField(Expr *E) const {
3675  if (E->isTypeDependent() || E->isValueDependent())
3676    return QualType();
3677
3678  FieldDecl *Field = E->getBitField();
3679  if (!Field)
3680    return QualType();
3681
3682  QualType FT = Field->getType();
3683
3684  uint64_t BitWidth = Field->getBitWidthValue(*this);
3685  uint64_t IntSize = getTypeSize(IntTy);
3686  // GCC extension compatibility: if the bit-field size is less than or equal
3687  // to the size of int, it gets promoted no matter what its type is.
3688  // For instance, unsigned long bf : 4 gets promoted to signed int.
3689  if (BitWidth < IntSize)
3690    return IntTy;
3691
3692  if (BitWidth == IntSize)
3693    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
3694
3695  // Types bigger than int are not subject to promotions, and therefore act
3696  // like the base type.
3697  // FIXME: This doesn't quite match what gcc does, but what gcc does here
3698  // is ridiculous.
3699  return QualType();
3700}
3701
3702/// getPromotedIntegerType - Returns the type that Promotable will
3703/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
3704/// integer type.
3705QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
3706  assert(!Promotable.isNull());
3707  assert(Promotable->isPromotableIntegerType());
3708  if (const EnumType *ET = Promotable->getAs<EnumType>())
3709    return ET->getDecl()->getPromotionType();
3710
3711  if (const BuiltinType *BT = Promotable->getAs<BuiltinType>()) {
3712    // C++ [conv.prom]: A prvalue of type char16_t, char32_t, or wchar_t
3713    // (3.9.1) can be converted to a prvalue of the first of the following
3714    // types that can represent all the values of its underlying type:
3715    // int, unsigned int, long int, unsigned long int, long long int, or
3716    // unsigned long long int [...]
3717    // FIXME: Is there some better way to compute this?
3718    if (BT->getKind() == BuiltinType::WChar_S ||
3719        BT->getKind() == BuiltinType::WChar_U ||
3720        BT->getKind() == BuiltinType::Char16 ||
3721        BT->getKind() == BuiltinType::Char32) {
3722      bool FromIsSigned = BT->getKind() == BuiltinType::WChar_S;
3723      uint64_t FromSize = getTypeSize(BT);
3724      QualType PromoteTypes[] = { IntTy, UnsignedIntTy, LongTy, UnsignedLongTy,
3725                                  LongLongTy, UnsignedLongLongTy };
3726      for (size_t Idx = 0; Idx < llvm::array_lengthof(PromoteTypes); ++Idx) {
3727        uint64_t ToSize = getTypeSize(PromoteTypes[Idx]);
3728        if (FromSize < ToSize ||
3729            (FromSize == ToSize &&
3730             FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType()))
3731          return PromoteTypes[Idx];
3732      }
3733      llvm_unreachable("char type should fit into long long");
3734    }
3735  }
3736
3737  // At this point, we should have a signed or unsigned integer type.
3738  if (Promotable->isSignedIntegerType())
3739    return IntTy;
3740  uint64_t PromotableSize = getTypeSize(Promotable);
3741  uint64_t IntSize = getTypeSize(IntTy);
3742  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3743  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3744}
3745
3746/// \brief Recurses in pointer/array types until it finds an objc retainable
3747/// type and returns its ownership.
3748Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
3749  while (!T.isNull()) {
3750    if (T.getObjCLifetime() != Qualifiers::OCL_None)
3751      return T.getObjCLifetime();
3752    if (T->isArrayType())
3753      T = getBaseElementType(T);
3754    else if (const PointerType *PT = T->getAs<PointerType>())
3755      T = PT->getPointeeType();
3756    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3757      T = RT->getPointeeType();
3758    else
3759      break;
3760  }
3761
3762  return Qualifiers::OCL_None;
3763}
3764
3765/// getIntegerTypeOrder - Returns the highest ranked integer type:
3766/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3767/// LHS < RHS, return -1.
3768int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
3769  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
3770  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
3771  if (LHSC == RHSC) return 0;
3772
3773  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3774  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3775
3776  unsigned LHSRank = getIntegerRank(LHSC);
3777  unsigned RHSRank = getIntegerRank(RHSC);
3778
3779  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3780    if (LHSRank == RHSRank) return 0;
3781    return LHSRank > RHSRank ? 1 : -1;
3782  }
3783
3784  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3785  if (LHSUnsigned) {
3786    // If the unsigned [LHS] type is larger, return it.
3787    if (LHSRank >= RHSRank)
3788      return 1;
3789
3790    // If the signed type can represent all values of the unsigned type, it
3791    // wins.  Because we are dealing with 2's complement and types that are
3792    // powers of two larger than each other, this is always safe.
3793    return -1;
3794  }
3795
3796  // If the unsigned [RHS] type is larger, return it.
3797  if (RHSRank >= LHSRank)
3798    return -1;
3799
3800  // If the signed type can represent all values of the unsigned type, it
3801  // wins.  Because we are dealing with 2's complement and types that are
3802  // powers of two larger than each other, this is always safe.
3803  return 1;
3804}
3805
3806static RecordDecl *
3807CreateRecordDecl(const ASTContext &Ctx, RecordDecl::TagKind TK,
3808                 DeclContext *DC, IdentifierInfo *Id) {
3809  SourceLocation Loc;
3810  if (Ctx.getLangOptions().CPlusPlus)
3811    return CXXRecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3812  else
3813    return RecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3814}
3815
3816// getCFConstantStringType - Return the type used for constant CFStrings.
3817QualType ASTContext::getCFConstantStringType() const {
3818  if (!CFConstantStringTypeDecl) {
3819    CFConstantStringTypeDecl =
3820      CreateRecordDecl(*this, TTK_Struct, TUDecl,
3821                       &Idents.get("NSConstantString"));
3822    CFConstantStringTypeDecl->startDefinition();
3823
3824    QualType FieldTypes[4];
3825
3826    // const int *isa;
3827    FieldTypes[0] = getPointerType(IntTy.withConst());
3828    // int flags;
3829    FieldTypes[1] = IntTy;
3830    // const char *str;
3831    FieldTypes[2] = getPointerType(CharTy.withConst());
3832    // long length;
3833    FieldTypes[3] = LongTy;
3834
3835    // Create fields
3836    for (unsigned i = 0; i < 4; ++i) {
3837      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3838                                           SourceLocation(),
3839                                           SourceLocation(), 0,
3840                                           FieldTypes[i], /*TInfo=*/0,
3841                                           /*BitWidth=*/0,
3842                                           /*Mutable=*/false,
3843                                           /*HasInit=*/false);
3844      Field->setAccess(AS_public);
3845      CFConstantStringTypeDecl->addDecl(Field);
3846    }
3847
3848    CFConstantStringTypeDecl->completeDefinition();
3849  }
3850
3851  return getTagDeclType(CFConstantStringTypeDecl);
3852}
3853
3854void ASTContext::setCFConstantStringType(QualType T) {
3855  const RecordType *Rec = T->getAs<RecordType>();
3856  assert(Rec && "Invalid CFConstantStringType");
3857  CFConstantStringTypeDecl = Rec->getDecl();
3858}
3859
3860QualType ASTContext::getBlockDescriptorType() const {
3861  if (BlockDescriptorType)
3862    return getTagDeclType(BlockDescriptorType);
3863
3864  RecordDecl *T;
3865  // FIXME: Needs the FlagAppleBlock bit.
3866  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3867                       &Idents.get("__block_descriptor"));
3868  T->startDefinition();
3869
3870  QualType FieldTypes[] = {
3871    UnsignedLongTy,
3872    UnsignedLongTy,
3873  };
3874
3875  const char *FieldNames[] = {
3876    "reserved",
3877    "Size"
3878  };
3879
3880  for (size_t i = 0; i < 2; ++i) {
3881    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3882                                         SourceLocation(),
3883                                         &Idents.get(FieldNames[i]),
3884                                         FieldTypes[i], /*TInfo=*/0,
3885                                         /*BitWidth=*/0,
3886                                         /*Mutable=*/false,
3887                                         /*HasInit=*/false);
3888    Field->setAccess(AS_public);
3889    T->addDecl(Field);
3890  }
3891
3892  T->completeDefinition();
3893
3894  BlockDescriptorType = T;
3895
3896  return getTagDeclType(BlockDescriptorType);
3897}
3898
3899QualType ASTContext::getBlockDescriptorExtendedType() const {
3900  if (BlockDescriptorExtendedType)
3901    return getTagDeclType(BlockDescriptorExtendedType);
3902
3903  RecordDecl *T;
3904  // FIXME: Needs the FlagAppleBlock bit.
3905  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3906                       &Idents.get("__block_descriptor_withcopydispose"));
3907  T->startDefinition();
3908
3909  QualType FieldTypes[] = {
3910    UnsignedLongTy,
3911    UnsignedLongTy,
3912    getPointerType(VoidPtrTy),
3913    getPointerType(VoidPtrTy)
3914  };
3915
3916  const char *FieldNames[] = {
3917    "reserved",
3918    "Size",
3919    "CopyFuncPtr",
3920    "DestroyFuncPtr"
3921  };
3922
3923  for (size_t i = 0; i < 4; ++i) {
3924    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3925                                         SourceLocation(),
3926                                         &Idents.get(FieldNames[i]),
3927                                         FieldTypes[i], /*TInfo=*/0,
3928                                         /*BitWidth=*/0,
3929                                         /*Mutable=*/false,
3930                                         /*HasInit=*/false);
3931    Field->setAccess(AS_public);
3932    T->addDecl(Field);
3933  }
3934
3935  T->completeDefinition();
3936
3937  BlockDescriptorExtendedType = T;
3938
3939  return getTagDeclType(BlockDescriptorExtendedType);
3940}
3941
3942bool ASTContext::BlockRequiresCopying(QualType Ty) const {
3943  if (Ty->isObjCRetainableType())
3944    return true;
3945  if (getLangOptions().CPlusPlus) {
3946    if (const RecordType *RT = Ty->getAs<RecordType>()) {
3947      CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
3948      return RD->hasConstCopyConstructor();
3949
3950    }
3951  }
3952  return false;
3953}
3954
3955QualType
3956ASTContext::BuildByRefType(StringRef DeclName, QualType Ty) const {
3957  //  type = struct __Block_byref_1_X {
3958  //    void *__isa;
3959  //    struct __Block_byref_1_X *__forwarding;
3960  //    unsigned int __flags;
3961  //    unsigned int __size;
3962  //    void *__copy_helper;            // as needed
3963  //    void *__destroy_help            // as needed
3964  //    int X;
3965  //  } *
3966
3967  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3968
3969  // FIXME: Move up
3970  SmallString<36> Name;
3971  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3972                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3973  RecordDecl *T;
3974  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, &Idents.get(Name.str()));
3975  T->startDefinition();
3976  QualType Int32Ty = IntTy;
3977  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3978  QualType FieldTypes[] = {
3979    getPointerType(VoidPtrTy),
3980    getPointerType(getTagDeclType(T)),
3981    Int32Ty,
3982    Int32Ty,
3983    getPointerType(VoidPtrTy),
3984    getPointerType(VoidPtrTy),
3985    Ty
3986  };
3987
3988  StringRef FieldNames[] = {
3989    "__isa",
3990    "__forwarding",
3991    "__flags",
3992    "__size",
3993    "__copy_helper",
3994    "__destroy_helper",
3995    DeclName,
3996  };
3997
3998  for (size_t i = 0; i < 7; ++i) {
3999    if (!HasCopyAndDispose && i >=4 && i <= 5)
4000      continue;
4001    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
4002                                         SourceLocation(),
4003                                         &Idents.get(FieldNames[i]),
4004                                         FieldTypes[i], /*TInfo=*/0,
4005                                         /*BitWidth=*/0, /*Mutable=*/false,
4006                                         /*HasInit=*/false);
4007    Field->setAccess(AS_public);
4008    T->addDecl(Field);
4009  }
4010
4011  T->completeDefinition();
4012
4013  return getPointerType(getTagDeclType(T));
4014}
4015
4016TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
4017  if (!ObjCInstanceTypeDecl)
4018    ObjCInstanceTypeDecl = TypedefDecl::Create(*this,
4019                                               getTranslationUnitDecl(),
4020                                               SourceLocation(),
4021                                               SourceLocation(),
4022                                               &Idents.get("instancetype"),
4023                                     getTrivialTypeSourceInfo(getObjCIdType()));
4024  return ObjCInstanceTypeDecl;
4025}
4026
4027// This returns true if a type has been typedefed to BOOL:
4028// typedef <type> BOOL;
4029static bool isTypeTypedefedAsBOOL(QualType T) {
4030  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
4031    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
4032      return II->isStr("BOOL");
4033
4034  return false;
4035}
4036
4037/// getObjCEncodingTypeSize returns size of type for objective-c encoding
4038/// purpose.
4039CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
4040  if (!type->isIncompleteArrayType() && type->isIncompleteType())
4041    return CharUnits::Zero();
4042
4043  CharUnits sz = getTypeSizeInChars(type);
4044
4045  // Make all integer and enum types at least as large as an int
4046  if (sz.isPositive() && type->isIntegralOrEnumerationType())
4047    sz = std::max(sz, getTypeSizeInChars(IntTy));
4048  // Treat arrays as pointers, since that's how they're passed in.
4049  else if (type->isArrayType())
4050    sz = getTypeSizeInChars(VoidPtrTy);
4051  return sz;
4052}
4053
4054static inline
4055std::string charUnitsToString(const CharUnits &CU) {
4056  return llvm::itostr(CU.getQuantity());
4057}
4058
4059/// getObjCEncodingForBlock - Return the encoded type for this block
4060/// declaration.
4061std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
4062  std::string S;
4063
4064  const BlockDecl *Decl = Expr->getBlockDecl();
4065  QualType BlockTy =
4066      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
4067  // Encode result type.
4068  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
4069  // Compute size of all parameters.
4070  // Start with computing size of a pointer in number of bytes.
4071  // FIXME: There might(should) be a better way of doing this computation!
4072  SourceLocation Loc;
4073  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4074  CharUnits ParmOffset = PtrSize;
4075  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
4076       E = Decl->param_end(); PI != E; ++PI) {
4077    QualType PType = (*PI)->getType();
4078    CharUnits sz = getObjCEncodingTypeSize(PType);
4079    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
4080    ParmOffset += sz;
4081  }
4082  // Size of the argument frame
4083  S += charUnitsToString(ParmOffset);
4084  // Block pointer and offset.
4085  S += "@?0";
4086
4087  // Argument types.
4088  ParmOffset = PtrSize;
4089  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
4090       Decl->param_end(); PI != E; ++PI) {
4091    ParmVarDecl *PVDecl = *PI;
4092    QualType PType = PVDecl->getOriginalType();
4093    if (const ArrayType *AT =
4094          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4095      // Use array's original type only if it has known number of
4096      // elements.
4097      if (!isa<ConstantArrayType>(AT))
4098        PType = PVDecl->getType();
4099    } else if (PType->isFunctionType())
4100      PType = PVDecl->getType();
4101    getObjCEncodingForType(PType, S);
4102    S += charUnitsToString(ParmOffset);
4103    ParmOffset += getObjCEncodingTypeSize(PType);
4104  }
4105
4106  return S;
4107}
4108
4109bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
4110                                                std::string& S) {
4111  // Encode result type.
4112  getObjCEncodingForType(Decl->getResultType(), S);
4113  CharUnits ParmOffset;
4114  // Compute size of all parameters.
4115  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4116       E = Decl->param_end(); PI != E; ++PI) {
4117    QualType PType = (*PI)->getType();
4118    CharUnits sz = getObjCEncodingTypeSize(PType);
4119    if (sz.isZero())
4120      return true;
4121
4122    assert (sz.isPositive() &&
4123        "getObjCEncodingForFunctionDecl - Incomplete param type");
4124    ParmOffset += sz;
4125  }
4126  S += charUnitsToString(ParmOffset);
4127  ParmOffset = CharUnits::Zero();
4128
4129  // Argument types.
4130  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4131       E = Decl->param_end(); PI != E; ++PI) {
4132    ParmVarDecl *PVDecl = *PI;
4133    QualType PType = PVDecl->getOriginalType();
4134    if (const ArrayType *AT =
4135          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4136      // Use array's original type only if it has known number of
4137      // elements.
4138      if (!isa<ConstantArrayType>(AT))
4139        PType = PVDecl->getType();
4140    } else if (PType->isFunctionType())
4141      PType = PVDecl->getType();
4142    getObjCEncodingForType(PType, S);
4143    S += charUnitsToString(ParmOffset);
4144    ParmOffset += getObjCEncodingTypeSize(PType);
4145  }
4146
4147  return false;
4148}
4149
4150/// getObjCEncodingForMethodParameter - Return the encoded type for a single
4151/// method parameter or return type. If Extended, include class names and
4152/// block object types.
4153void ASTContext::getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
4154                                                   QualType T, std::string& S,
4155                                                   bool Extended) const {
4156  // Encode type qualifer, 'in', 'inout', etc. for the parameter.
4157  getObjCEncodingForTypeQualifier(QT, S);
4158  // Encode parameter type.
4159  getObjCEncodingForTypeImpl(T, S, true, true, 0,
4160                             true     /*OutermostType*/,
4161                             false    /*EncodingProperty*/,
4162                             false    /*StructField*/,
4163                             Extended /*EncodeBlockParameters*/,
4164                             Extended /*EncodeClassNames*/);
4165}
4166
4167/// getObjCEncodingForMethodDecl - Return the encoded type for this method
4168/// declaration.
4169bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
4170                                              std::string& S,
4171                                              bool Extended) const {
4172  // FIXME: This is not very efficient.
4173  // Encode return type.
4174  getObjCEncodingForMethodParameter(Decl->getObjCDeclQualifier(),
4175                                    Decl->getResultType(), S, Extended);
4176  // Compute size of all parameters.
4177  // Start with computing size of a pointer in number of bytes.
4178  // FIXME: There might(should) be a better way of doing this computation!
4179  SourceLocation Loc;
4180  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4181  // The first two arguments (self and _cmd) are pointers; account for
4182  // their size.
4183  CharUnits ParmOffset = 2 * PtrSize;
4184  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4185       E = Decl->sel_param_end(); PI != E; ++PI) {
4186    QualType PType = (*PI)->getType();
4187    CharUnits sz = getObjCEncodingTypeSize(PType);
4188    if (sz.isZero())
4189      return true;
4190
4191    assert (sz.isPositive() &&
4192        "getObjCEncodingForMethodDecl - Incomplete param type");
4193    ParmOffset += sz;
4194  }
4195  S += charUnitsToString(ParmOffset);
4196  S += "@0:";
4197  S += charUnitsToString(PtrSize);
4198
4199  // Argument types.
4200  ParmOffset = 2 * PtrSize;
4201  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4202       E = Decl->sel_param_end(); PI != E; ++PI) {
4203    const ParmVarDecl *PVDecl = *PI;
4204    QualType PType = PVDecl->getOriginalType();
4205    if (const ArrayType *AT =
4206          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4207      // Use array's original type only if it has known number of
4208      // elements.
4209      if (!isa<ConstantArrayType>(AT))
4210        PType = PVDecl->getType();
4211    } else if (PType->isFunctionType())
4212      PType = PVDecl->getType();
4213    getObjCEncodingForMethodParameter(PVDecl->getObjCDeclQualifier(),
4214                                      PType, S, Extended);
4215    S += charUnitsToString(ParmOffset);
4216    ParmOffset += getObjCEncodingTypeSize(PType);
4217  }
4218
4219  return false;
4220}
4221
4222/// getObjCEncodingForPropertyDecl - Return the encoded type for this
4223/// property declaration. If non-NULL, Container must be either an
4224/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
4225/// NULL when getting encodings for protocol properties.
4226/// Property attributes are stored as a comma-delimited C string. The simple
4227/// attributes readonly and bycopy are encoded as single characters. The
4228/// parametrized attributes, getter=name, setter=name, and ivar=name, are
4229/// encoded as single characters, followed by an identifier. Property types
4230/// are also encoded as a parametrized attribute. The characters used to encode
4231/// these attributes are defined by the following enumeration:
4232/// @code
4233/// enum PropertyAttributes {
4234/// kPropertyReadOnly = 'R',   // property is read-only.
4235/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
4236/// kPropertyByref = '&',  // property is a reference to the value last assigned
4237/// kPropertyDynamic = 'D',    // property is dynamic
4238/// kPropertyGetter = 'G',     // followed by getter selector name
4239/// kPropertySetter = 'S',     // followed by setter selector name
4240/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
4241/// kPropertyType = 't'              // followed by old-style type encoding.
4242/// kPropertyWeak = 'W'              // 'weak' property
4243/// kPropertyStrong = 'P'            // property GC'able
4244/// kPropertyNonAtomic = 'N'         // property non-atomic
4245/// };
4246/// @endcode
4247void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
4248                                                const Decl *Container,
4249                                                std::string& S) const {
4250  // Collect information from the property implementation decl(s).
4251  bool Dynamic = false;
4252  ObjCPropertyImplDecl *SynthesizePID = 0;
4253
4254  // FIXME: Duplicated code due to poor abstraction.
4255  if (Container) {
4256    if (const ObjCCategoryImplDecl *CID =
4257        dyn_cast<ObjCCategoryImplDecl>(Container)) {
4258      for (ObjCCategoryImplDecl::propimpl_iterator
4259             i = CID->propimpl_begin(), e = CID->propimpl_end();
4260           i != e; ++i) {
4261        ObjCPropertyImplDecl *PID = *i;
4262        if (PID->getPropertyDecl() == PD) {
4263          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4264            Dynamic = true;
4265          } else {
4266            SynthesizePID = PID;
4267          }
4268        }
4269      }
4270    } else {
4271      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
4272      for (ObjCCategoryImplDecl::propimpl_iterator
4273             i = OID->propimpl_begin(), e = OID->propimpl_end();
4274           i != e; ++i) {
4275        ObjCPropertyImplDecl *PID = *i;
4276        if (PID->getPropertyDecl() == PD) {
4277          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4278            Dynamic = true;
4279          } else {
4280            SynthesizePID = PID;
4281          }
4282        }
4283      }
4284    }
4285  }
4286
4287  // FIXME: This is not very efficient.
4288  S = "T";
4289
4290  // Encode result type.
4291  // GCC has some special rules regarding encoding of properties which
4292  // closely resembles encoding of ivars.
4293  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
4294                             true /* outermost type */,
4295                             true /* encoding for property */);
4296
4297  if (PD->isReadOnly()) {
4298    S += ",R";
4299  } else {
4300    switch (PD->getSetterKind()) {
4301    case ObjCPropertyDecl::Assign: break;
4302    case ObjCPropertyDecl::Copy:   S += ",C"; break;
4303    case ObjCPropertyDecl::Retain: S += ",&"; break;
4304    case ObjCPropertyDecl::Weak:   S += ",W"; break;
4305    }
4306  }
4307
4308  // It really isn't clear at all what this means, since properties
4309  // are "dynamic by default".
4310  if (Dynamic)
4311    S += ",D";
4312
4313  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
4314    S += ",N";
4315
4316  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
4317    S += ",G";
4318    S += PD->getGetterName().getAsString();
4319  }
4320
4321  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
4322    S += ",S";
4323    S += PD->getSetterName().getAsString();
4324  }
4325
4326  if (SynthesizePID) {
4327    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
4328    S += ",V";
4329    S += OID->getNameAsString();
4330  }
4331
4332  // FIXME: OBJCGC: weak & strong
4333}
4334
4335/// getLegacyIntegralTypeEncoding -
4336/// Another legacy compatibility encoding: 32-bit longs are encoded as
4337/// 'l' or 'L' , but not always.  For typedefs, we need to use
4338/// 'i' or 'I' instead if encoding a struct field, or a pointer!
4339///
4340void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
4341  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
4342    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
4343      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
4344        PointeeTy = UnsignedIntTy;
4345      else
4346        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
4347          PointeeTy = IntTy;
4348    }
4349  }
4350}
4351
4352void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
4353                                        const FieldDecl *Field) const {
4354  // We follow the behavior of gcc, expanding structures which are
4355  // directly pointed to, and expanding embedded structures. Note that
4356  // these rules are sufficient to prevent recursive encoding of the
4357  // same type.
4358  getObjCEncodingForTypeImpl(T, S, true, true, Field,
4359                             true /* outermost type */);
4360}
4361
4362static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
4363    switch (T->getAs<BuiltinType>()->getKind()) {
4364    default: llvm_unreachable("Unhandled builtin type kind");
4365    case BuiltinType::Void:       return 'v';
4366    case BuiltinType::Bool:       return 'B';
4367    case BuiltinType::Char_U:
4368    case BuiltinType::UChar:      return 'C';
4369    case BuiltinType::UShort:     return 'S';
4370    case BuiltinType::UInt:       return 'I';
4371    case BuiltinType::ULong:
4372        return C->getIntWidth(T) == 32 ? 'L' : 'Q';
4373    case BuiltinType::UInt128:    return 'T';
4374    case BuiltinType::ULongLong:  return 'Q';
4375    case BuiltinType::Char_S:
4376    case BuiltinType::SChar:      return 'c';
4377    case BuiltinType::Short:      return 's';
4378    case BuiltinType::WChar_S:
4379    case BuiltinType::WChar_U:
4380    case BuiltinType::Int:        return 'i';
4381    case BuiltinType::Long:
4382      return C->getIntWidth(T) == 32 ? 'l' : 'q';
4383    case BuiltinType::LongLong:   return 'q';
4384    case BuiltinType::Int128:     return 't';
4385    case BuiltinType::Float:      return 'f';
4386    case BuiltinType::Double:     return 'd';
4387    case BuiltinType::LongDouble: return 'D';
4388    }
4389}
4390
4391static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
4392  EnumDecl *Enum = ET->getDecl();
4393
4394  // The encoding of an non-fixed enum type is always 'i', regardless of size.
4395  if (!Enum->isFixed())
4396    return 'i';
4397
4398  // The encoding of a fixed enum type matches its fixed underlying type.
4399  return ObjCEncodingForPrimitiveKind(C, Enum->getIntegerType());
4400}
4401
4402static void EncodeBitField(const ASTContext *Ctx, std::string& S,
4403                           QualType T, const FieldDecl *FD) {
4404  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
4405  S += 'b';
4406  // The NeXT runtime encodes bit fields as b followed by the number of bits.
4407  // The GNU runtime requires more information; bitfields are encoded as b,
4408  // then the offset (in bits) of the first element, then the type of the
4409  // bitfield, then the size in bits.  For example, in this structure:
4410  //
4411  // struct
4412  // {
4413  //    int integer;
4414  //    int flags:2;
4415  // };
4416  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
4417  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
4418  // information is not especially sensible, but we're stuck with it for
4419  // compatibility with GCC, although providing it breaks anything that
4420  // actually uses runtime introspection and wants to work on both runtimes...
4421  if (!Ctx->getLangOptions().NeXTRuntime) {
4422    const RecordDecl *RD = FD->getParent();
4423    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
4424    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
4425    if (const EnumType *ET = T->getAs<EnumType>())
4426      S += ObjCEncodingForEnumType(Ctx, ET);
4427    else
4428      S += ObjCEncodingForPrimitiveKind(Ctx, T);
4429  }
4430  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
4431}
4432
4433// FIXME: Use SmallString for accumulating string.
4434void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
4435                                            bool ExpandPointedToStructures,
4436                                            bool ExpandStructures,
4437                                            const FieldDecl *FD,
4438                                            bool OutermostType,
4439                                            bool EncodingProperty,
4440                                            bool StructField,
4441                                            bool EncodeBlockParameters,
4442                                            bool EncodeClassNames) const {
4443  if (T->getAs<BuiltinType>()) {
4444    if (FD && FD->isBitField())
4445      return EncodeBitField(this, S, T, FD);
4446    S += ObjCEncodingForPrimitiveKind(this, T);
4447    return;
4448  }
4449
4450  if (const ComplexType *CT = T->getAs<ComplexType>()) {
4451    S += 'j';
4452    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
4453                               false);
4454    return;
4455  }
4456
4457  // encoding for pointer or r3eference types.
4458  QualType PointeeTy;
4459  if (const PointerType *PT = T->getAs<PointerType>()) {
4460    if (PT->isObjCSelType()) {
4461      S += ':';
4462      return;
4463    }
4464    PointeeTy = PT->getPointeeType();
4465  }
4466  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4467    PointeeTy = RT->getPointeeType();
4468  if (!PointeeTy.isNull()) {
4469    bool isReadOnly = false;
4470    // For historical/compatibility reasons, the read-only qualifier of the
4471    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
4472    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
4473    // Also, do not emit the 'r' for anything but the outermost type!
4474    if (isa<TypedefType>(T.getTypePtr())) {
4475      if (OutermostType && T.isConstQualified()) {
4476        isReadOnly = true;
4477        S += 'r';
4478      }
4479    } else if (OutermostType) {
4480      QualType P = PointeeTy;
4481      while (P->getAs<PointerType>())
4482        P = P->getAs<PointerType>()->getPointeeType();
4483      if (P.isConstQualified()) {
4484        isReadOnly = true;
4485        S += 'r';
4486      }
4487    }
4488    if (isReadOnly) {
4489      // Another legacy compatibility encoding. Some ObjC qualifier and type
4490      // combinations need to be rearranged.
4491      // Rewrite "in const" from "nr" to "rn"
4492      if (StringRef(S).endswith("nr"))
4493        S.replace(S.end()-2, S.end(), "rn");
4494    }
4495
4496    if (PointeeTy->isCharType()) {
4497      // char pointer types should be encoded as '*' unless it is a
4498      // type that has been typedef'd to 'BOOL'.
4499      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
4500        S += '*';
4501        return;
4502      }
4503    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
4504      // GCC binary compat: Need to convert "struct objc_class *" to "#".
4505      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
4506        S += '#';
4507        return;
4508      }
4509      // GCC binary compat: Need to convert "struct objc_object *" to "@".
4510      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
4511        S += '@';
4512        return;
4513      }
4514      // fall through...
4515    }
4516    S += '^';
4517    getLegacyIntegralTypeEncoding(PointeeTy);
4518
4519    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
4520                               NULL);
4521    return;
4522  }
4523
4524  if (const ArrayType *AT =
4525      // Ignore type qualifiers etc.
4526        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
4527    if (isa<IncompleteArrayType>(AT) && !StructField) {
4528      // Incomplete arrays are encoded as a pointer to the array element.
4529      S += '^';
4530
4531      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4532                                 false, ExpandStructures, FD);
4533    } else {
4534      S += '[';
4535
4536      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
4537        if (getTypeSize(CAT->getElementType()) == 0)
4538          S += '0';
4539        else
4540          S += llvm::utostr(CAT->getSize().getZExtValue());
4541      } else {
4542        //Variable length arrays are encoded as a regular array with 0 elements.
4543        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
4544               "Unknown array type!");
4545        S += '0';
4546      }
4547
4548      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4549                                 false, ExpandStructures, FD);
4550      S += ']';
4551    }
4552    return;
4553  }
4554
4555  if (T->getAs<FunctionType>()) {
4556    S += '?';
4557    return;
4558  }
4559
4560  if (const RecordType *RTy = T->getAs<RecordType>()) {
4561    RecordDecl *RDecl = RTy->getDecl();
4562    S += RDecl->isUnion() ? '(' : '{';
4563    // Anonymous structures print as '?'
4564    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
4565      S += II->getName();
4566      if (ClassTemplateSpecializationDecl *Spec
4567          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
4568        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
4569        std::string TemplateArgsStr
4570          = TemplateSpecializationType::PrintTemplateArgumentList(
4571                                            TemplateArgs.data(),
4572                                            TemplateArgs.size(),
4573                                            (*this).getPrintingPolicy());
4574
4575        S += TemplateArgsStr;
4576      }
4577    } else {
4578      S += '?';
4579    }
4580    if (ExpandStructures) {
4581      S += '=';
4582      if (!RDecl->isUnion()) {
4583        getObjCEncodingForStructureImpl(RDecl, S, FD);
4584      } else {
4585        for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4586                                     FieldEnd = RDecl->field_end();
4587             Field != FieldEnd; ++Field) {
4588          if (FD) {
4589            S += '"';
4590            S += Field->getNameAsString();
4591            S += '"';
4592          }
4593
4594          // Special case bit-fields.
4595          if (Field->isBitField()) {
4596            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
4597                                       (*Field));
4598          } else {
4599            QualType qt = Field->getType();
4600            getLegacyIntegralTypeEncoding(qt);
4601            getObjCEncodingForTypeImpl(qt, S, false, true,
4602                                       FD, /*OutermostType*/false,
4603                                       /*EncodingProperty*/false,
4604                                       /*StructField*/true);
4605          }
4606        }
4607      }
4608    }
4609    S += RDecl->isUnion() ? ')' : '}';
4610    return;
4611  }
4612
4613  if (const EnumType *ET = T->getAs<EnumType>()) {
4614    if (FD && FD->isBitField())
4615      EncodeBitField(this, S, T, FD);
4616    else
4617      S += ObjCEncodingForEnumType(this, ET);
4618    return;
4619  }
4620
4621  if (const BlockPointerType *BT = T->getAs<BlockPointerType>()) {
4622    S += "@?"; // Unlike a pointer-to-function, which is "^?".
4623    if (EncodeBlockParameters) {
4624      const FunctionType *FT = BT->getPointeeType()->getAs<FunctionType>();
4625
4626      S += '<';
4627      // Block return type
4628      getObjCEncodingForTypeImpl(FT->getResultType(), S,
4629                                 ExpandPointedToStructures, ExpandStructures,
4630                                 FD,
4631                                 false /* OutermostType */,
4632                                 EncodingProperty,
4633                                 false /* StructField */,
4634                                 EncodeBlockParameters,
4635                                 EncodeClassNames);
4636      // Block self
4637      S += "@?";
4638      // Block parameters
4639      if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT)) {
4640        for (FunctionProtoType::arg_type_iterator I = FPT->arg_type_begin(),
4641               E = FPT->arg_type_end(); I && (I != E); ++I) {
4642          getObjCEncodingForTypeImpl(*I, S,
4643                                     ExpandPointedToStructures,
4644                                     ExpandStructures,
4645                                     FD,
4646                                     false /* OutermostType */,
4647                                     EncodingProperty,
4648                                     false /* StructField */,
4649                                     EncodeBlockParameters,
4650                                     EncodeClassNames);
4651        }
4652      }
4653      S += '>';
4654    }
4655    return;
4656  }
4657
4658  // Ignore protocol qualifiers when mangling at this level.
4659  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
4660    T = OT->getBaseType();
4661
4662  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
4663    // @encode(class_name)
4664    ObjCInterfaceDecl *OI = OIT->getDecl();
4665    S += '{';
4666    const IdentifierInfo *II = OI->getIdentifier();
4667    S += II->getName();
4668    S += '=';
4669    SmallVector<const ObjCIvarDecl*, 32> Ivars;
4670    DeepCollectObjCIvars(OI, true, Ivars);
4671    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
4672      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
4673      if (Field->isBitField())
4674        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
4675      else
4676        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
4677    }
4678    S += '}';
4679    return;
4680  }
4681
4682  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
4683    if (OPT->isObjCIdType()) {
4684      S += '@';
4685      return;
4686    }
4687
4688    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
4689      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
4690      // Since this is a binary compatibility issue, need to consult with runtime
4691      // folks. Fortunately, this is a *very* obsure construct.
4692      S += '#';
4693      return;
4694    }
4695
4696    if (OPT->isObjCQualifiedIdType()) {
4697      getObjCEncodingForTypeImpl(getObjCIdType(), S,
4698                                 ExpandPointedToStructures,
4699                                 ExpandStructures, FD);
4700      if (FD || EncodingProperty || EncodeClassNames) {
4701        // Note that we do extended encoding of protocol qualifer list
4702        // Only when doing ivar or property encoding.
4703        S += '"';
4704        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4705             E = OPT->qual_end(); I != E; ++I) {
4706          S += '<';
4707          S += (*I)->getNameAsString();
4708          S += '>';
4709        }
4710        S += '"';
4711      }
4712      return;
4713    }
4714
4715    QualType PointeeTy = OPT->getPointeeType();
4716    if (!EncodingProperty &&
4717        isa<TypedefType>(PointeeTy.getTypePtr())) {
4718      // Another historical/compatibility reason.
4719      // We encode the underlying type which comes out as
4720      // {...};
4721      S += '^';
4722      getObjCEncodingForTypeImpl(PointeeTy, S,
4723                                 false, ExpandPointedToStructures,
4724                                 NULL);
4725      return;
4726    }
4727
4728    S += '@';
4729    if (OPT->getInterfaceDecl() &&
4730        (FD || EncodingProperty || EncodeClassNames)) {
4731      S += '"';
4732      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4733      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4734           E = OPT->qual_end(); I != E; ++I) {
4735        S += '<';
4736        S += (*I)->getNameAsString();
4737        S += '>';
4738      }
4739      S += '"';
4740    }
4741    return;
4742  }
4743
4744  // gcc just blithely ignores member pointers.
4745  // TODO: maybe there should be a mangling for these
4746  if (T->getAs<MemberPointerType>())
4747    return;
4748
4749  if (T->isVectorType()) {
4750    // This matches gcc's encoding, even though technically it is
4751    // insufficient.
4752    // FIXME. We should do a better job than gcc.
4753    return;
4754  }
4755
4756  llvm_unreachable("@encode for type not implemented!");
4757}
4758
4759void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
4760                                                 std::string &S,
4761                                                 const FieldDecl *FD,
4762                                                 bool includeVBases) const {
4763  assert(RDecl && "Expected non-null RecordDecl");
4764  assert(!RDecl->isUnion() && "Should not be called for unions");
4765  if (!RDecl->getDefinition())
4766    return;
4767
4768  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
4769  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
4770  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
4771
4772  if (CXXRec) {
4773    for (CXXRecordDecl::base_class_iterator
4774           BI = CXXRec->bases_begin(),
4775           BE = CXXRec->bases_end(); BI != BE; ++BI) {
4776      if (!BI->isVirtual()) {
4777        CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4778        if (base->isEmpty())
4779          continue;
4780        uint64_t offs = layout.getBaseClassOffsetInBits(base);
4781        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4782                                  std::make_pair(offs, base));
4783      }
4784    }
4785  }
4786
4787  unsigned i = 0;
4788  for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4789                               FieldEnd = RDecl->field_end();
4790       Field != FieldEnd; ++Field, ++i) {
4791    uint64_t offs = layout.getFieldOffset(i);
4792    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4793                              std::make_pair(offs, *Field));
4794  }
4795
4796  if (CXXRec && includeVBases) {
4797    for (CXXRecordDecl::base_class_iterator
4798           BI = CXXRec->vbases_begin(),
4799           BE = CXXRec->vbases_end(); BI != BE; ++BI) {
4800      CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4801      if (base->isEmpty())
4802        continue;
4803      uint64_t offs = layout.getVBaseClassOffsetInBits(base);
4804      if (FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
4805        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
4806                                  std::make_pair(offs, base));
4807    }
4808  }
4809
4810  CharUnits size;
4811  if (CXXRec) {
4812    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
4813  } else {
4814    size = layout.getSize();
4815  }
4816
4817  uint64_t CurOffs = 0;
4818  std::multimap<uint64_t, NamedDecl *>::iterator
4819    CurLayObj = FieldOrBaseOffsets.begin();
4820
4821  if ((CurLayObj != FieldOrBaseOffsets.end() && CurLayObj->first != 0) ||
4822      (CurLayObj == FieldOrBaseOffsets.end() &&
4823         CXXRec && CXXRec->isDynamicClass())) {
4824    assert(CXXRec && CXXRec->isDynamicClass() &&
4825           "Offset 0 was empty but no VTable ?");
4826    if (FD) {
4827      S += "\"_vptr$";
4828      std::string recname = CXXRec->getNameAsString();
4829      if (recname.empty()) recname = "?";
4830      S += recname;
4831      S += '"';
4832    }
4833    S += "^^?";
4834    CurOffs += getTypeSize(VoidPtrTy);
4835  }
4836
4837  if (!RDecl->hasFlexibleArrayMember()) {
4838    // Mark the end of the structure.
4839    uint64_t offs = toBits(size);
4840    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4841                              std::make_pair(offs, (NamedDecl*)0));
4842  }
4843
4844  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
4845    assert(CurOffs <= CurLayObj->first);
4846
4847    if (CurOffs < CurLayObj->first) {
4848      uint64_t padding = CurLayObj->first - CurOffs;
4849      // FIXME: There doesn't seem to be a way to indicate in the encoding that
4850      // packing/alignment of members is different that normal, in which case
4851      // the encoding will be out-of-sync with the real layout.
4852      // If the runtime switches to just consider the size of types without
4853      // taking into account alignment, we could make padding explicit in the
4854      // encoding (e.g. using arrays of chars). The encoding strings would be
4855      // longer then though.
4856      CurOffs += padding;
4857    }
4858
4859    NamedDecl *dcl = CurLayObj->second;
4860    if (dcl == 0)
4861      break; // reached end of structure.
4862
4863    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
4864      // We expand the bases without their virtual bases since those are going
4865      // in the initial structure. Note that this differs from gcc which
4866      // expands virtual bases each time one is encountered in the hierarchy,
4867      // making the encoding type bigger than it really is.
4868      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false);
4869      assert(!base->isEmpty());
4870      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
4871    } else {
4872      FieldDecl *field = cast<FieldDecl>(dcl);
4873      if (FD) {
4874        S += '"';
4875        S += field->getNameAsString();
4876        S += '"';
4877      }
4878
4879      if (field->isBitField()) {
4880        EncodeBitField(this, S, field->getType(), field);
4881        CurOffs += field->getBitWidthValue(*this);
4882      } else {
4883        QualType qt = field->getType();
4884        getLegacyIntegralTypeEncoding(qt);
4885        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
4886                                   /*OutermostType*/false,
4887                                   /*EncodingProperty*/false,
4888                                   /*StructField*/true);
4889        CurOffs += getTypeSize(field->getType());
4890      }
4891    }
4892  }
4893}
4894
4895void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4896                                                 std::string& S) const {
4897  if (QT & Decl::OBJC_TQ_In)
4898    S += 'n';
4899  if (QT & Decl::OBJC_TQ_Inout)
4900    S += 'N';
4901  if (QT & Decl::OBJC_TQ_Out)
4902    S += 'o';
4903  if (QT & Decl::OBJC_TQ_Bycopy)
4904    S += 'O';
4905  if (QT & Decl::OBJC_TQ_Byref)
4906    S += 'R';
4907  if (QT & Decl::OBJC_TQ_Oneway)
4908    S += 'V';
4909}
4910
4911void ASTContext::setBuiltinVaListType(QualType T) {
4912  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4913
4914  BuiltinVaListType = T;
4915}
4916
4917TypedefDecl *ASTContext::getObjCIdDecl() const {
4918  if (!ObjCIdDecl) {
4919    QualType T = getObjCObjectType(ObjCBuiltinIdTy, 0, 0);
4920    T = getObjCObjectPointerType(T);
4921    TypeSourceInfo *IdInfo = getTrivialTypeSourceInfo(T);
4922    ObjCIdDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4923                                     getTranslationUnitDecl(),
4924                                     SourceLocation(), SourceLocation(),
4925                                     &Idents.get("id"), IdInfo);
4926  }
4927
4928  return ObjCIdDecl;
4929}
4930
4931TypedefDecl *ASTContext::getObjCSelDecl() const {
4932  if (!ObjCSelDecl) {
4933    QualType SelT = getPointerType(ObjCBuiltinSelTy);
4934    TypeSourceInfo *SelInfo = getTrivialTypeSourceInfo(SelT);
4935    ObjCSelDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4936                                      getTranslationUnitDecl(),
4937                                      SourceLocation(), SourceLocation(),
4938                                      &Idents.get("SEL"), SelInfo);
4939  }
4940  return ObjCSelDecl;
4941}
4942
4943TypedefDecl *ASTContext::getObjCClassDecl() const {
4944  if (!ObjCClassDecl) {
4945    QualType T = getObjCObjectType(ObjCBuiltinClassTy, 0, 0);
4946    T = getObjCObjectPointerType(T);
4947    TypeSourceInfo *ClassInfo = getTrivialTypeSourceInfo(T);
4948    ObjCClassDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4949                                        getTranslationUnitDecl(),
4950                                        SourceLocation(), SourceLocation(),
4951                                        &Idents.get("Class"), ClassInfo);
4952  }
4953
4954  return ObjCClassDecl;
4955}
4956
4957ObjCInterfaceDecl *ASTContext::getObjCProtocolDecl() const {
4958  if (!ObjCProtocolClassDecl) {
4959    ObjCProtocolClassDecl
4960      = ObjCInterfaceDecl::Create(*this, getTranslationUnitDecl(),
4961                                  SourceLocation(),
4962                                  &Idents.get("Protocol"),
4963                                  /*PrevDecl=*/0,
4964                                  SourceLocation(), true);
4965  }
4966
4967  return ObjCProtocolClassDecl;
4968}
4969
4970void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4971  assert(ObjCConstantStringType.isNull() &&
4972         "'NSConstantString' type already set!");
4973
4974  ObjCConstantStringType = getObjCInterfaceType(Decl);
4975}
4976
4977/// \brief Retrieve the template name that corresponds to a non-empty
4978/// lookup.
4979TemplateName
4980ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4981                                      UnresolvedSetIterator End) const {
4982  unsigned size = End - Begin;
4983  assert(size > 1 && "set is not overloaded!");
4984
4985  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4986                          size * sizeof(FunctionTemplateDecl*));
4987  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4988
4989  NamedDecl **Storage = OT->getStorage();
4990  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4991    NamedDecl *D = *I;
4992    assert(isa<FunctionTemplateDecl>(D) ||
4993           (isa<UsingShadowDecl>(D) &&
4994            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4995    *Storage++ = D;
4996  }
4997
4998  return TemplateName(OT);
4999}
5000
5001/// \brief Retrieve the template name that represents a qualified
5002/// template name such as \c std::vector.
5003TemplateName
5004ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
5005                                     bool TemplateKeyword,
5006                                     TemplateDecl *Template) const {
5007  assert(NNS && "Missing nested-name-specifier in qualified template name");
5008
5009  // FIXME: Canonicalization?
5010  llvm::FoldingSetNodeID ID;
5011  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
5012
5013  void *InsertPos = 0;
5014  QualifiedTemplateName *QTN =
5015    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5016  if (!QTN) {
5017    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
5018    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
5019  }
5020
5021  return TemplateName(QTN);
5022}
5023
5024/// \brief Retrieve the template name that represents a dependent
5025/// template name such as \c MetaFun::template apply.
5026TemplateName
5027ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
5028                                     const IdentifierInfo *Name) const {
5029  assert((!NNS || NNS->isDependent()) &&
5030         "Nested name specifier must be dependent");
5031
5032  llvm::FoldingSetNodeID ID;
5033  DependentTemplateName::Profile(ID, NNS, Name);
5034
5035  void *InsertPos = 0;
5036  DependentTemplateName *QTN =
5037    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5038
5039  if (QTN)
5040    return TemplateName(QTN);
5041
5042  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
5043  if (CanonNNS == NNS) {
5044    QTN = new (*this,4) DependentTemplateName(NNS, Name);
5045  } else {
5046    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
5047    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
5048    DependentTemplateName *CheckQTN =
5049      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5050    assert(!CheckQTN && "Dependent type name canonicalization broken");
5051    (void)CheckQTN;
5052  }
5053
5054  DependentTemplateNames.InsertNode(QTN, InsertPos);
5055  return TemplateName(QTN);
5056}
5057
5058/// \brief Retrieve the template name that represents a dependent
5059/// template name such as \c MetaFun::template operator+.
5060TemplateName
5061ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
5062                                     OverloadedOperatorKind Operator) const {
5063  assert((!NNS || NNS->isDependent()) &&
5064         "Nested name specifier must be dependent");
5065
5066  llvm::FoldingSetNodeID ID;
5067  DependentTemplateName::Profile(ID, NNS, Operator);
5068
5069  void *InsertPos = 0;
5070  DependentTemplateName *QTN
5071    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5072
5073  if (QTN)
5074    return TemplateName(QTN);
5075
5076  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
5077  if (CanonNNS == NNS) {
5078    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
5079  } else {
5080    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
5081    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
5082
5083    DependentTemplateName *CheckQTN
5084      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5085    assert(!CheckQTN && "Dependent template name canonicalization broken");
5086    (void)CheckQTN;
5087  }
5088
5089  DependentTemplateNames.InsertNode(QTN, InsertPos);
5090  return TemplateName(QTN);
5091}
5092
5093TemplateName
5094ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
5095                                         TemplateName replacement) const {
5096  llvm::FoldingSetNodeID ID;
5097  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
5098
5099  void *insertPos = 0;
5100  SubstTemplateTemplateParmStorage *subst
5101    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
5102
5103  if (!subst) {
5104    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
5105    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
5106  }
5107
5108  return TemplateName(subst);
5109}
5110
5111TemplateName
5112ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
5113                                       const TemplateArgument &ArgPack) const {
5114  ASTContext &Self = const_cast<ASTContext &>(*this);
5115  llvm::FoldingSetNodeID ID;
5116  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
5117
5118  void *InsertPos = 0;
5119  SubstTemplateTemplateParmPackStorage *Subst
5120    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
5121
5122  if (!Subst) {
5123    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
5124                                                           ArgPack.pack_size(),
5125                                                         ArgPack.pack_begin());
5126    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
5127  }
5128
5129  return TemplateName(Subst);
5130}
5131
5132/// getFromTargetType - Given one of the integer types provided by
5133/// TargetInfo, produce the corresponding type. The unsigned @p Type
5134/// is actually a value of type @c TargetInfo::IntType.
5135CanQualType ASTContext::getFromTargetType(unsigned Type) const {
5136  switch (Type) {
5137  case TargetInfo::NoInt: return CanQualType();
5138  case TargetInfo::SignedShort: return ShortTy;
5139  case TargetInfo::UnsignedShort: return UnsignedShortTy;
5140  case TargetInfo::SignedInt: return IntTy;
5141  case TargetInfo::UnsignedInt: return UnsignedIntTy;
5142  case TargetInfo::SignedLong: return LongTy;
5143  case TargetInfo::UnsignedLong: return UnsignedLongTy;
5144  case TargetInfo::SignedLongLong: return LongLongTy;
5145  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
5146  }
5147
5148  llvm_unreachable("Unhandled TargetInfo::IntType value");
5149}
5150
5151//===----------------------------------------------------------------------===//
5152//                        Type Predicates.
5153//===----------------------------------------------------------------------===//
5154
5155/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
5156/// garbage collection attribute.
5157///
5158Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
5159  if (getLangOptions().getGC() == LangOptions::NonGC)
5160    return Qualifiers::GCNone;
5161
5162  assert(getLangOptions().ObjC1);
5163  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
5164
5165  // Default behaviour under objective-C's gc is for ObjC pointers
5166  // (or pointers to them) be treated as though they were declared
5167  // as __strong.
5168  if (GCAttrs == Qualifiers::GCNone) {
5169    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
5170      return Qualifiers::Strong;
5171    else if (Ty->isPointerType())
5172      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
5173  } else {
5174    // It's not valid to set GC attributes on anything that isn't a
5175    // pointer.
5176#ifndef NDEBUG
5177    QualType CT = Ty->getCanonicalTypeInternal();
5178    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
5179      CT = AT->getElementType();
5180    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
5181#endif
5182  }
5183  return GCAttrs;
5184}
5185
5186//===----------------------------------------------------------------------===//
5187//                        Type Compatibility Testing
5188//===----------------------------------------------------------------------===//
5189
5190/// areCompatVectorTypes - Return true if the two specified vector types are
5191/// compatible.
5192static bool areCompatVectorTypes(const VectorType *LHS,
5193                                 const VectorType *RHS) {
5194  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
5195  return LHS->getElementType() == RHS->getElementType() &&
5196         LHS->getNumElements() == RHS->getNumElements();
5197}
5198
5199bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
5200                                          QualType SecondVec) {
5201  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
5202  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
5203
5204  if (hasSameUnqualifiedType(FirstVec, SecondVec))
5205    return true;
5206
5207  // Treat Neon vector types and most AltiVec vector types as if they are the
5208  // equivalent GCC vector types.
5209  const VectorType *First = FirstVec->getAs<VectorType>();
5210  const VectorType *Second = SecondVec->getAs<VectorType>();
5211  if (First->getNumElements() == Second->getNumElements() &&
5212      hasSameType(First->getElementType(), Second->getElementType()) &&
5213      First->getVectorKind() != VectorType::AltiVecPixel &&
5214      First->getVectorKind() != VectorType::AltiVecBool &&
5215      Second->getVectorKind() != VectorType::AltiVecPixel &&
5216      Second->getVectorKind() != VectorType::AltiVecBool)
5217    return true;
5218
5219  return false;
5220}
5221
5222//===----------------------------------------------------------------------===//
5223// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
5224//===----------------------------------------------------------------------===//
5225
5226/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
5227/// inheritance hierarchy of 'rProto'.
5228bool
5229ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
5230                                           ObjCProtocolDecl *rProto) const {
5231  if (declaresSameEntity(lProto, rProto))
5232    return true;
5233  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
5234       E = rProto->protocol_end(); PI != E; ++PI)
5235    if (ProtocolCompatibleWithProtocol(lProto, *PI))
5236      return true;
5237  return false;
5238}
5239
5240/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
5241/// return true if lhs's protocols conform to rhs's protocol; false
5242/// otherwise.
5243bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
5244  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
5245    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
5246  return false;
5247}
5248
5249/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
5250/// Class<p1, ...>.
5251bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
5252                                                      QualType rhs) {
5253  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
5254  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5255  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
5256
5257  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5258       E = lhsQID->qual_end(); I != E; ++I) {
5259    bool match = false;
5260    ObjCProtocolDecl *lhsProto = *I;
5261    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5262         E = rhsOPT->qual_end(); J != E; ++J) {
5263      ObjCProtocolDecl *rhsProto = *J;
5264      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
5265        match = true;
5266        break;
5267      }
5268    }
5269    if (!match)
5270      return false;
5271  }
5272  return true;
5273}
5274
5275/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
5276/// ObjCQualifiedIDType.
5277bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
5278                                                   bool compare) {
5279  // Allow id<P..> and an 'id' or void* type in all cases.
5280  if (lhs->isVoidPointerType() ||
5281      lhs->isObjCIdType() || lhs->isObjCClassType())
5282    return true;
5283  else if (rhs->isVoidPointerType() ||
5284           rhs->isObjCIdType() || rhs->isObjCClassType())
5285    return true;
5286
5287  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
5288    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5289
5290    if (!rhsOPT) return false;
5291
5292    if (rhsOPT->qual_empty()) {
5293      // If the RHS is a unqualified interface pointer "NSString*",
5294      // make sure we check the class hierarchy.
5295      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5296        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5297             E = lhsQID->qual_end(); I != E; ++I) {
5298          // when comparing an id<P> on lhs with a static type on rhs,
5299          // see if static class implements all of id's protocols, directly or
5300          // through its super class and categories.
5301          if (!rhsID->ClassImplementsProtocol(*I, true))
5302            return false;
5303        }
5304      }
5305      // If there are no qualifiers and no interface, we have an 'id'.
5306      return true;
5307    }
5308    // Both the right and left sides have qualifiers.
5309    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5310         E = lhsQID->qual_end(); I != E; ++I) {
5311      ObjCProtocolDecl *lhsProto = *I;
5312      bool match = false;
5313
5314      // when comparing an id<P> on lhs with a static type on rhs,
5315      // see if static class implements all of id's protocols, directly or
5316      // through its super class and categories.
5317      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5318           E = rhsOPT->qual_end(); J != E; ++J) {
5319        ObjCProtocolDecl *rhsProto = *J;
5320        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5321            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5322          match = true;
5323          break;
5324        }
5325      }
5326      // If the RHS is a qualified interface pointer "NSString<P>*",
5327      // make sure we check the class hierarchy.
5328      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5329        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5330             E = lhsQID->qual_end(); I != E; ++I) {
5331          // when comparing an id<P> on lhs with a static type on rhs,
5332          // see if static class implements all of id's protocols, directly or
5333          // through its super class and categories.
5334          if (rhsID->ClassImplementsProtocol(*I, true)) {
5335            match = true;
5336            break;
5337          }
5338        }
5339      }
5340      if (!match)
5341        return false;
5342    }
5343
5344    return true;
5345  }
5346
5347  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
5348  assert(rhsQID && "One of the LHS/RHS should be id<x>");
5349
5350  if (const ObjCObjectPointerType *lhsOPT =
5351        lhs->getAsObjCInterfacePointerType()) {
5352    // If both the right and left sides have qualifiers.
5353    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
5354         E = lhsOPT->qual_end(); I != E; ++I) {
5355      ObjCProtocolDecl *lhsProto = *I;
5356      bool match = false;
5357
5358      // when comparing an id<P> on rhs with a static type on lhs,
5359      // see if static class implements all of id's protocols, directly or
5360      // through its super class and categories.
5361      // First, lhs protocols in the qualifier list must be found, direct
5362      // or indirect in rhs's qualifier list or it is a mismatch.
5363      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5364           E = rhsQID->qual_end(); J != E; ++J) {
5365        ObjCProtocolDecl *rhsProto = *J;
5366        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5367            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5368          match = true;
5369          break;
5370        }
5371      }
5372      if (!match)
5373        return false;
5374    }
5375
5376    // Static class's protocols, or its super class or category protocols
5377    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
5378    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
5379      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5380      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
5381      // This is rather dubious but matches gcc's behavior. If lhs has
5382      // no type qualifier and its class has no static protocol(s)
5383      // assume that it is mismatch.
5384      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
5385        return false;
5386      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5387           LHSInheritedProtocols.begin(),
5388           E = LHSInheritedProtocols.end(); I != E; ++I) {
5389        bool match = false;
5390        ObjCProtocolDecl *lhsProto = (*I);
5391        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5392             E = rhsQID->qual_end(); J != E; ++J) {
5393          ObjCProtocolDecl *rhsProto = *J;
5394          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5395              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5396            match = true;
5397            break;
5398          }
5399        }
5400        if (!match)
5401          return false;
5402      }
5403    }
5404    return true;
5405  }
5406  return false;
5407}
5408
5409/// canAssignObjCInterfaces - Return true if the two interface types are
5410/// compatible for assignment from RHS to LHS.  This handles validation of any
5411/// protocol qualifiers on the LHS or RHS.
5412///
5413bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
5414                                         const ObjCObjectPointerType *RHSOPT) {
5415  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5416  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5417
5418  // If either type represents the built-in 'id' or 'Class' types, return true.
5419  if (LHS->isObjCUnqualifiedIdOrClass() ||
5420      RHS->isObjCUnqualifiedIdOrClass())
5421    return true;
5422
5423  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
5424    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5425                                             QualType(RHSOPT,0),
5426                                             false);
5427
5428  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
5429    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
5430                                                QualType(RHSOPT,0));
5431
5432  // If we have 2 user-defined types, fall into that path.
5433  if (LHS->getInterface() && RHS->getInterface())
5434    return canAssignObjCInterfaces(LHS, RHS);
5435
5436  return false;
5437}
5438
5439/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
5440/// for providing type-safety for objective-c pointers used to pass/return
5441/// arguments in block literals. When passed as arguments, passing 'A*' where
5442/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
5443/// not OK. For the return type, the opposite is not OK.
5444bool ASTContext::canAssignObjCInterfacesInBlockPointer(
5445                                         const ObjCObjectPointerType *LHSOPT,
5446                                         const ObjCObjectPointerType *RHSOPT,
5447                                         bool BlockReturnType) {
5448  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
5449    return true;
5450
5451  if (LHSOPT->isObjCBuiltinType()) {
5452    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
5453  }
5454
5455  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
5456    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5457                                             QualType(RHSOPT,0),
5458                                             false);
5459
5460  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
5461  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
5462  if (LHS && RHS)  { // We have 2 user-defined types.
5463    if (LHS != RHS) {
5464      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
5465        return BlockReturnType;
5466      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
5467        return !BlockReturnType;
5468    }
5469    else
5470      return true;
5471  }
5472  return false;
5473}
5474
5475/// getIntersectionOfProtocols - This routine finds the intersection of set
5476/// of protocols inherited from two distinct objective-c pointer objects.
5477/// It is used to build composite qualifier list of the composite type of
5478/// the conditional expression involving two objective-c pointer objects.
5479static
5480void getIntersectionOfProtocols(ASTContext &Context,
5481                                const ObjCObjectPointerType *LHSOPT,
5482                                const ObjCObjectPointerType *RHSOPT,
5483      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
5484
5485  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5486  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5487  assert(LHS->getInterface() && "LHS must have an interface base");
5488  assert(RHS->getInterface() && "RHS must have an interface base");
5489
5490  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
5491  unsigned LHSNumProtocols = LHS->getNumProtocols();
5492  if (LHSNumProtocols > 0)
5493    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
5494  else {
5495    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5496    Context.CollectInheritedProtocols(LHS->getInterface(),
5497                                      LHSInheritedProtocols);
5498    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
5499                                LHSInheritedProtocols.end());
5500  }
5501
5502  unsigned RHSNumProtocols = RHS->getNumProtocols();
5503  if (RHSNumProtocols > 0) {
5504    ObjCProtocolDecl **RHSProtocols =
5505      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
5506    for (unsigned i = 0; i < RHSNumProtocols; ++i)
5507      if (InheritedProtocolSet.count(RHSProtocols[i]))
5508        IntersectionOfProtocols.push_back(RHSProtocols[i]);
5509  } else {
5510    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
5511    Context.CollectInheritedProtocols(RHS->getInterface(),
5512                                      RHSInheritedProtocols);
5513    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5514         RHSInheritedProtocols.begin(),
5515         E = RHSInheritedProtocols.end(); I != E; ++I)
5516      if (InheritedProtocolSet.count((*I)))
5517        IntersectionOfProtocols.push_back((*I));
5518  }
5519}
5520
5521/// areCommonBaseCompatible - Returns common base class of the two classes if
5522/// one found. Note that this is O'2 algorithm. But it will be called as the
5523/// last type comparison in a ?-exp of ObjC pointer types before a
5524/// warning is issued. So, its invokation is extremely rare.
5525QualType ASTContext::areCommonBaseCompatible(
5526                                          const ObjCObjectPointerType *Lptr,
5527                                          const ObjCObjectPointerType *Rptr) {
5528  const ObjCObjectType *LHS = Lptr->getObjectType();
5529  const ObjCObjectType *RHS = Rptr->getObjectType();
5530  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
5531  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
5532  if (!LDecl || !RDecl || (declaresSameEntity(LDecl, RDecl)))
5533    return QualType();
5534
5535  do {
5536    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
5537    if (canAssignObjCInterfaces(LHS, RHS)) {
5538      SmallVector<ObjCProtocolDecl *, 8> Protocols;
5539      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
5540
5541      QualType Result = QualType(LHS, 0);
5542      if (!Protocols.empty())
5543        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
5544      Result = getObjCObjectPointerType(Result);
5545      return Result;
5546    }
5547  } while ((LDecl = LDecl->getSuperClass()));
5548
5549  return QualType();
5550}
5551
5552bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
5553                                         const ObjCObjectType *RHS) {
5554  assert(LHS->getInterface() && "LHS is not an interface type");
5555  assert(RHS->getInterface() && "RHS is not an interface type");
5556
5557  // Verify that the base decls are compatible: the RHS must be a subclass of
5558  // the LHS.
5559  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
5560    return false;
5561
5562  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
5563  // protocol qualified at all, then we are good.
5564  if (LHS->getNumProtocols() == 0)
5565    return true;
5566
5567  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't,
5568  // more detailed analysis is required.
5569  if (RHS->getNumProtocols() == 0) {
5570    // OK, if LHS is a superclass of RHS *and*
5571    // this superclass is assignment compatible with LHS.
5572    // false otherwise.
5573    bool IsSuperClass =
5574      LHS->getInterface()->isSuperClassOf(RHS->getInterface());
5575    if (IsSuperClass) {
5576      // OK if conversion of LHS to SuperClass results in narrowing of types
5577      // ; i.e., SuperClass may implement at least one of the protocols
5578      // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
5579      // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
5580      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
5581      CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
5582      // If super class has no protocols, it is not a match.
5583      if (SuperClassInheritedProtocols.empty())
5584        return false;
5585
5586      for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5587           LHSPE = LHS->qual_end();
5588           LHSPI != LHSPE; LHSPI++) {
5589        bool SuperImplementsProtocol = false;
5590        ObjCProtocolDecl *LHSProto = (*LHSPI);
5591
5592        for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5593             SuperClassInheritedProtocols.begin(),
5594             E = SuperClassInheritedProtocols.end(); I != E; ++I) {
5595          ObjCProtocolDecl *SuperClassProto = (*I);
5596          if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
5597            SuperImplementsProtocol = true;
5598            break;
5599          }
5600        }
5601        if (!SuperImplementsProtocol)
5602          return false;
5603      }
5604      return true;
5605    }
5606    return false;
5607  }
5608
5609  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5610                                     LHSPE = LHS->qual_end();
5611       LHSPI != LHSPE; LHSPI++) {
5612    bool RHSImplementsProtocol = false;
5613
5614    // If the RHS doesn't implement the protocol on the left, the types
5615    // are incompatible.
5616    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
5617                                       RHSPE = RHS->qual_end();
5618         RHSPI != RHSPE; RHSPI++) {
5619      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
5620        RHSImplementsProtocol = true;
5621        break;
5622      }
5623    }
5624    // FIXME: For better diagnostics, consider passing back the protocol name.
5625    if (!RHSImplementsProtocol)
5626      return false;
5627  }
5628  // The RHS implements all protocols listed on the LHS.
5629  return true;
5630}
5631
5632bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
5633  // get the "pointed to" types
5634  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
5635  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
5636
5637  if (!LHSOPT || !RHSOPT)
5638    return false;
5639
5640  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
5641         canAssignObjCInterfaces(RHSOPT, LHSOPT);
5642}
5643
5644bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
5645  return canAssignObjCInterfaces(
5646                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
5647                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
5648}
5649
5650/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
5651/// both shall have the identically qualified version of a compatible type.
5652/// C99 6.2.7p1: Two types have compatible types if their types are the
5653/// same. See 6.7.[2,3,5] for additional rules.
5654bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
5655                                    bool CompareUnqualified) {
5656  if (getLangOptions().CPlusPlus)
5657    return hasSameType(LHS, RHS);
5658
5659  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
5660}
5661
5662bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
5663  return typesAreCompatible(LHS, RHS);
5664}
5665
5666bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
5667  return !mergeTypes(LHS, RHS, true).isNull();
5668}
5669
5670/// mergeTransparentUnionType - if T is a transparent union type and a member
5671/// of T is compatible with SubType, return the merged type, else return
5672/// QualType()
5673QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
5674                                               bool OfBlockPointer,
5675                                               bool Unqualified) {
5676  if (const RecordType *UT = T->getAsUnionType()) {
5677    RecordDecl *UD = UT->getDecl();
5678    if (UD->hasAttr<TransparentUnionAttr>()) {
5679      for (RecordDecl::field_iterator it = UD->field_begin(),
5680           itend = UD->field_end(); it != itend; ++it) {
5681        QualType ET = it->getType().getUnqualifiedType();
5682        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
5683        if (!MT.isNull())
5684          return MT;
5685      }
5686    }
5687  }
5688
5689  return QualType();
5690}
5691
5692/// mergeFunctionArgumentTypes - merge two types which appear as function
5693/// argument types
5694QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
5695                                                bool OfBlockPointer,
5696                                                bool Unqualified) {
5697  // GNU extension: two types are compatible if they appear as a function
5698  // argument, one of the types is a transparent union type and the other
5699  // type is compatible with a union member
5700  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
5701                                              Unqualified);
5702  if (!lmerge.isNull())
5703    return lmerge;
5704
5705  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
5706                                              Unqualified);
5707  if (!rmerge.isNull())
5708    return rmerge;
5709
5710  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
5711}
5712
5713QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
5714                                        bool OfBlockPointer,
5715                                        bool Unqualified) {
5716  const FunctionType *lbase = lhs->getAs<FunctionType>();
5717  const FunctionType *rbase = rhs->getAs<FunctionType>();
5718  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
5719  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
5720  bool allLTypes = true;
5721  bool allRTypes = true;
5722
5723  // Check return type
5724  QualType retType;
5725  if (OfBlockPointer) {
5726    QualType RHS = rbase->getResultType();
5727    QualType LHS = lbase->getResultType();
5728    bool UnqualifiedResult = Unqualified;
5729    if (!UnqualifiedResult)
5730      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
5731    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
5732  }
5733  else
5734    retType = mergeTypes(lbase->getResultType(), rbase->getResultType(), false,
5735                         Unqualified);
5736  if (retType.isNull()) return QualType();
5737
5738  if (Unqualified)
5739    retType = retType.getUnqualifiedType();
5740
5741  CanQualType LRetType = getCanonicalType(lbase->getResultType());
5742  CanQualType RRetType = getCanonicalType(rbase->getResultType());
5743  if (Unqualified) {
5744    LRetType = LRetType.getUnqualifiedType();
5745    RRetType = RRetType.getUnqualifiedType();
5746  }
5747
5748  if (getCanonicalType(retType) != LRetType)
5749    allLTypes = false;
5750  if (getCanonicalType(retType) != RRetType)
5751    allRTypes = false;
5752
5753  // FIXME: double check this
5754  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
5755  //                           rbase->getRegParmAttr() != 0 &&
5756  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
5757  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
5758  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
5759
5760  // Compatible functions must have compatible calling conventions
5761  if (!isSameCallConv(lbaseInfo.getCC(), rbaseInfo.getCC()))
5762    return QualType();
5763
5764  // Regparm is part of the calling convention.
5765  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
5766    return QualType();
5767  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
5768    return QualType();
5769
5770  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
5771    return QualType();
5772
5773  // functypes which return are preferred over those that do not.
5774  if (lbaseInfo.getNoReturn() && !rbaseInfo.getNoReturn())
5775    allLTypes = false;
5776  else if (!lbaseInfo.getNoReturn() && rbaseInfo.getNoReturn())
5777    allRTypes = false;
5778  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
5779  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
5780
5781  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
5782
5783  if (lproto && rproto) { // two C99 style function prototypes
5784    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
5785           "C++ shouldn't be here");
5786    unsigned lproto_nargs = lproto->getNumArgs();
5787    unsigned rproto_nargs = rproto->getNumArgs();
5788
5789    // Compatible functions must have the same number of arguments
5790    if (lproto_nargs != rproto_nargs)
5791      return QualType();
5792
5793    // Variadic and non-variadic functions aren't compatible
5794    if (lproto->isVariadic() != rproto->isVariadic())
5795      return QualType();
5796
5797    if (lproto->getTypeQuals() != rproto->getTypeQuals())
5798      return QualType();
5799
5800    if (LangOpts.ObjCAutoRefCount &&
5801        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
5802      return QualType();
5803
5804    // Check argument compatibility
5805    SmallVector<QualType, 10> types;
5806    for (unsigned i = 0; i < lproto_nargs; i++) {
5807      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
5808      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
5809      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
5810                                                    OfBlockPointer,
5811                                                    Unqualified);
5812      if (argtype.isNull()) return QualType();
5813
5814      if (Unqualified)
5815        argtype = argtype.getUnqualifiedType();
5816
5817      types.push_back(argtype);
5818      if (Unqualified) {
5819        largtype = largtype.getUnqualifiedType();
5820        rargtype = rargtype.getUnqualifiedType();
5821      }
5822
5823      if (getCanonicalType(argtype) != getCanonicalType(largtype))
5824        allLTypes = false;
5825      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
5826        allRTypes = false;
5827    }
5828
5829    if (allLTypes) return lhs;
5830    if (allRTypes) return rhs;
5831
5832    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
5833    EPI.ExtInfo = einfo;
5834    return getFunctionType(retType, types.begin(), types.size(), EPI);
5835  }
5836
5837  if (lproto) allRTypes = false;
5838  if (rproto) allLTypes = false;
5839
5840  const FunctionProtoType *proto = lproto ? lproto : rproto;
5841  if (proto) {
5842    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
5843    if (proto->isVariadic()) return QualType();
5844    // Check that the types are compatible with the types that
5845    // would result from default argument promotions (C99 6.7.5.3p15).
5846    // The only types actually affected are promotable integer
5847    // types and floats, which would be passed as a different
5848    // type depending on whether the prototype is visible.
5849    unsigned proto_nargs = proto->getNumArgs();
5850    for (unsigned i = 0; i < proto_nargs; ++i) {
5851      QualType argTy = proto->getArgType(i);
5852
5853      // Look at the promotion type of enum types, since that is the type used
5854      // to pass enum values.
5855      if (const EnumType *Enum = argTy->getAs<EnumType>())
5856        argTy = Enum->getDecl()->getPromotionType();
5857
5858      if (argTy->isPromotableIntegerType() ||
5859          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
5860        return QualType();
5861    }
5862
5863    if (allLTypes) return lhs;
5864    if (allRTypes) return rhs;
5865
5866    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
5867    EPI.ExtInfo = einfo;
5868    return getFunctionType(retType, proto->arg_type_begin(),
5869                           proto->getNumArgs(), EPI);
5870  }
5871
5872  if (allLTypes) return lhs;
5873  if (allRTypes) return rhs;
5874  return getFunctionNoProtoType(retType, einfo);
5875}
5876
5877QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
5878                                bool OfBlockPointer,
5879                                bool Unqualified, bool BlockReturnType) {
5880  // C++ [expr]: If an expression initially has the type "reference to T", the
5881  // type is adjusted to "T" prior to any further analysis, the expression
5882  // designates the object or function denoted by the reference, and the
5883  // expression is an lvalue unless the reference is an rvalue reference and
5884  // the expression is a function call (possibly inside parentheses).
5885  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
5886  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
5887
5888  if (Unqualified) {
5889    LHS = LHS.getUnqualifiedType();
5890    RHS = RHS.getUnqualifiedType();
5891  }
5892
5893  QualType LHSCan = getCanonicalType(LHS),
5894           RHSCan = getCanonicalType(RHS);
5895
5896  // If two types are identical, they are compatible.
5897  if (LHSCan == RHSCan)
5898    return LHS;
5899
5900  // If the qualifiers are different, the types aren't compatible... mostly.
5901  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5902  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5903  if (LQuals != RQuals) {
5904    // If any of these qualifiers are different, we have a type
5905    // mismatch.
5906    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5907        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
5908        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
5909      return QualType();
5910
5911    // Exactly one GC qualifier difference is allowed: __strong is
5912    // okay if the other type has no GC qualifier but is an Objective
5913    // C object pointer (i.e. implicitly strong by default).  We fix
5914    // this by pretending that the unqualified type was actually
5915    // qualified __strong.
5916    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5917    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5918    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5919
5920    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5921      return QualType();
5922
5923    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
5924      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
5925    }
5926    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
5927      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
5928    }
5929    return QualType();
5930  }
5931
5932  // Okay, qualifiers are equal.
5933
5934  Type::TypeClass LHSClass = LHSCan->getTypeClass();
5935  Type::TypeClass RHSClass = RHSCan->getTypeClass();
5936
5937  // We want to consider the two function types to be the same for these
5938  // comparisons, just force one to the other.
5939  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
5940  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
5941
5942  // Same as above for arrays
5943  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
5944    LHSClass = Type::ConstantArray;
5945  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
5946    RHSClass = Type::ConstantArray;
5947
5948  // ObjCInterfaces are just specialized ObjCObjects.
5949  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
5950  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
5951
5952  // Canonicalize ExtVector -> Vector.
5953  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
5954  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
5955
5956  // If the canonical type classes don't match.
5957  if (LHSClass != RHSClass) {
5958    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
5959    // a signed integer type, or an unsigned integer type.
5960    // Compatibility is based on the underlying type, not the promotion
5961    // type.
5962    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
5963      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
5964        return RHS;
5965    }
5966    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
5967      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
5968        return LHS;
5969    }
5970    // allow block pointer type to match an 'id' type.
5971    if (OfBlockPointer && !BlockReturnType) {
5972       if (LHS->isObjCIdType() && RHS->isBlockPointerType())
5973         return LHS;
5974      if (RHS->isObjCIdType() && LHS->isBlockPointerType())
5975        return RHS;
5976    }
5977
5978    return QualType();
5979  }
5980
5981  // The canonical type classes match.
5982  switch (LHSClass) {
5983#define TYPE(Class, Base)
5984#define ABSTRACT_TYPE(Class, Base)
5985#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
5986#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
5987#define DEPENDENT_TYPE(Class, Base) case Type::Class:
5988#include "clang/AST/TypeNodes.def"
5989    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
5990
5991  case Type::LValueReference:
5992  case Type::RValueReference:
5993  case Type::MemberPointer:
5994    llvm_unreachable("C++ should never be in mergeTypes");
5995
5996  case Type::ObjCInterface:
5997  case Type::IncompleteArray:
5998  case Type::VariableArray:
5999  case Type::FunctionProto:
6000  case Type::ExtVector:
6001    llvm_unreachable("Types are eliminated above");
6002
6003  case Type::Pointer:
6004  {
6005    // Merge two pointer types, while trying to preserve typedef info
6006    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
6007    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
6008    if (Unqualified) {
6009      LHSPointee = LHSPointee.getUnqualifiedType();
6010      RHSPointee = RHSPointee.getUnqualifiedType();
6011    }
6012    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
6013                                     Unqualified);
6014    if (ResultType.isNull()) return QualType();
6015    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
6016      return LHS;
6017    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
6018      return RHS;
6019    return getPointerType(ResultType);
6020  }
6021  case Type::BlockPointer:
6022  {
6023    // Merge two block pointer types, while trying to preserve typedef info
6024    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
6025    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
6026    if (Unqualified) {
6027      LHSPointee = LHSPointee.getUnqualifiedType();
6028      RHSPointee = RHSPointee.getUnqualifiedType();
6029    }
6030    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
6031                                     Unqualified);
6032    if (ResultType.isNull()) return QualType();
6033    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
6034      return LHS;
6035    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
6036      return RHS;
6037    return getBlockPointerType(ResultType);
6038  }
6039  case Type::Atomic:
6040  {
6041    // Merge two pointer types, while trying to preserve typedef info
6042    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
6043    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
6044    if (Unqualified) {
6045      LHSValue = LHSValue.getUnqualifiedType();
6046      RHSValue = RHSValue.getUnqualifiedType();
6047    }
6048    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
6049                                     Unqualified);
6050    if (ResultType.isNull()) return QualType();
6051    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
6052      return LHS;
6053    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
6054      return RHS;
6055    return getAtomicType(ResultType);
6056  }
6057  case Type::ConstantArray:
6058  {
6059    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
6060    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
6061    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
6062      return QualType();
6063
6064    QualType LHSElem = getAsArrayType(LHS)->getElementType();
6065    QualType RHSElem = getAsArrayType(RHS)->getElementType();
6066    if (Unqualified) {
6067      LHSElem = LHSElem.getUnqualifiedType();
6068      RHSElem = RHSElem.getUnqualifiedType();
6069    }
6070
6071    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
6072    if (ResultType.isNull()) return QualType();
6073    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
6074      return LHS;
6075    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
6076      return RHS;
6077    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
6078                                          ArrayType::ArraySizeModifier(), 0);
6079    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
6080                                          ArrayType::ArraySizeModifier(), 0);
6081    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
6082    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
6083    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
6084      return LHS;
6085    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
6086      return RHS;
6087    if (LVAT) {
6088      // FIXME: This isn't correct! But tricky to implement because
6089      // the array's size has to be the size of LHS, but the type
6090      // has to be different.
6091      return LHS;
6092    }
6093    if (RVAT) {
6094      // FIXME: This isn't correct! But tricky to implement because
6095      // the array's size has to be the size of RHS, but the type
6096      // has to be different.
6097      return RHS;
6098    }
6099    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
6100    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
6101    return getIncompleteArrayType(ResultType,
6102                                  ArrayType::ArraySizeModifier(), 0);
6103  }
6104  case Type::FunctionNoProto:
6105    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
6106  case Type::Record:
6107  case Type::Enum:
6108    return QualType();
6109  case Type::Builtin:
6110    // Only exactly equal builtin types are compatible, which is tested above.
6111    return QualType();
6112  case Type::Complex:
6113    // Distinct complex types are incompatible.
6114    return QualType();
6115  case Type::Vector:
6116    // FIXME: The merged type should be an ExtVector!
6117    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
6118                             RHSCan->getAs<VectorType>()))
6119      return LHS;
6120    return QualType();
6121  case Type::ObjCObject: {
6122    // Check if the types are assignment compatible.
6123    // FIXME: This should be type compatibility, e.g. whether
6124    // "LHS x; RHS x;" at global scope is legal.
6125    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
6126    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
6127    if (canAssignObjCInterfaces(LHSIface, RHSIface))
6128      return LHS;
6129
6130    return QualType();
6131  }
6132  case Type::ObjCObjectPointer: {
6133    if (OfBlockPointer) {
6134      if (canAssignObjCInterfacesInBlockPointer(
6135                                          LHS->getAs<ObjCObjectPointerType>(),
6136                                          RHS->getAs<ObjCObjectPointerType>(),
6137                                          BlockReturnType))
6138        return LHS;
6139      return QualType();
6140    }
6141    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
6142                                RHS->getAs<ObjCObjectPointerType>()))
6143      return LHS;
6144
6145    return QualType();
6146  }
6147  }
6148
6149  llvm_unreachable("Invalid Type::Class!");
6150}
6151
6152bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
6153                   const FunctionProtoType *FromFunctionType,
6154                   const FunctionProtoType *ToFunctionType) {
6155  if (FromFunctionType->hasAnyConsumedArgs() !=
6156      ToFunctionType->hasAnyConsumedArgs())
6157    return false;
6158  FunctionProtoType::ExtProtoInfo FromEPI =
6159    FromFunctionType->getExtProtoInfo();
6160  FunctionProtoType::ExtProtoInfo ToEPI =
6161    ToFunctionType->getExtProtoInfo();
6162  if (FromEPI.ConsumedArguments && ToEPI.ConsumedArguments)
6163    for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs();
6164         ArgIdx != NumArgs; ++ArgIdx)  {
6165      if (FromEPI.ConsumedArguments[ArgIdx] !=
6166          ToEPI.ConsumedArguments[ArgIdx])
6167        return false;
6168    }
6169  return true;
6170}
6171
6172/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
6173/// 'RHS' attributes and returns the merged version; including for function
6174/// return types.
6175QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
6176  QualType LHSCan = getCanonicalType(LHS),
6177  RHSCan = getCanonicalType(RHS);
6178  // If two types are identical, they are compatible.
6179  if (LHSCan == RHSCan)
6180    return LHS;
6181  if (RHSCan->isFunctionType()) {
6182    if (!LHSCan->isFunctionType())
6183      return QualType();
6184    QualType OldReturnType =
6185      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
6186    QualType NewReturnType =
6187      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
6188    QualType ResReturnType =
6189      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
6190    if (ResReturnType.isNull())
6191      return QualType();
6192    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
6193      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
6194      // In either case, use OldReturnType to build the new function type.
6195      const FunctionType *F = LHS->getAs<FunctionType>();
6196      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
6197        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
6198        EPI.ExtInfo = getFunctionExtInfo(LHS);
6199        QualType ResultType
6200          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
6201                            FPT->getNumArgs(), EPI);
6202        return ResultType;
6203      }
6204    }
6205    return QualType();
6206  }
6207
6208  // If the qualifiers are different, the types can still be merged.
6209  Qualifiers LQuals = LHSCan.getLocalQualifiers();
6210  Qualifiers RQuals = RHSCan.getLocalQualifiers();
6211  if (LQuals != RQuals) {
6212    // If any of these qualifiers are different, we have a type mismatch.
6213    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
6214        LQuals.getAddressSpace() != RQuals.getAddressSpace())
6215      return QualType();
6216
6217    // Exactly one GC qualifier difference is allowed: __strong is
6218    // okay if the other type has no GC qualifier but is an Objective
6219    // C object pointer (i.e. implicitly strong by default).  We fix
6220    // this by pretending that the unqualified type was actually
6221    // qualified __strong.
6222    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
6223    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
6224    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
6225
6226    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
6227      return QualType();
6228
6229    if (GC_L == Qualifiers::Strong)
6230      return LHS;
6231    if (GC_R == Qualifiers::Strong)
6232      return RHS;
6233    return QualType();
6234  }
6235
6236  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
6237    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6238    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6239    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
6240    if (ResQT == LHSBaseQT)
6241      return LHS;
6242    if (ResQT == RHSBaseQT)
6243      return RHS;
6244  }
6245  return QualType();
6246}
6247
6248//===----------------------------------------------------------------------===//
6249//                         Integer Predicates
6250//===----------------------------------------------------------------------===//
6251
6252unsigned ASTContext::getIntWidth(QualType T) const {
6253  if (const EnumType *ET = dyn_cast<EnumType>(T))
6254    T = ET->getDecl()->getIntegerType();
6255  if (T->isBooleanType())
6256    return 1;
6257  // For builtin types, just use the standard type sizing method
6258  return (unsigned)getTypeSize(T);
6259}
6260
6261QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
6262  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
6263
6264  // Turn <4 x signed int> -> <4 x unsigned int>
6265  if (const VectorType *VTy = T->getAs<VectorType>())
6266    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
6267                         VTy->getNumElements(), VTy->getVectorKind());
6268
6269  // For enums, we return the unsigned version of the base type.
6270  if (const EnumType *ETy = T->getAs<EnumType>())
6271    T = ETy->getDecl()->getIntegerType();
6272
6273  const BuiltinType *BTy = T->getAs<BuiltinType>();
6274  assert(BTy && "Unexpected signed integer type");
6275  switch (BTy->getKind()) {
6276  case BuiltinType::Char_S:
6277  case BuiltinType::SChar:
6278    return UnsignedCharTy;
6279  case BuiltinType::Short:
6280    return UnsignedShortTy;
6281  case BuiltinType::Int:
6282    return UnsignedIntTy;
6283  case BuiltinType::Long:
6284    return UnsignedLongTy;
6285  case BuiltinType::LongLong:
6286    return UnsignedLongLongTy;
6287  case BuiltinType::Int128:
6288    return UnsignedInt128Ty;
6289  default:
6290    llvm_unreachable("Unexpected signed integer type");
6291  }
6292}
6293
6294ASTMutationListener::~ASTMutationListener() { }
6295
6296
6297//===----------------------------------------------------------------------===//
6298//                          Builtin Type Computation
6299//===----------------------------------------------------------------------===//
6300
6301/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
6302/// pointer over the consumed characters.  This returns the resultant type.  If
6303/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
6304/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
6305/// a vector of "i*".
6306///
6307/// RequiresICE is filled in on return to indicate whether the value is required
6308/// to be an Integer Constant Expression.
6309static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
6310                                  ASTContext::GetBuiltinTypeError &Error,
6311                                  bool &RequiresICE,
6312                                  bool AllowTypeModifiers) {
6313  // Modifiers.
6314  int HowLong = 0;
6315  bool Signed = false, Unsigned = false;
6316  RequiresICE = false;
6317
6318  // Read the prefixed modifiers first.
6319  bool Done = false;
6320  while (!Done) {
6321    switch (*Str++) {
6322    default: Done = true; --Str; break;
6323    case 'I':
6324      RequiresICE = true;
6325      break;
6326    case 'S':
6327      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
6328      assert(!Signed && "Can't use 'S' modifier multiple times!");
6329      Signed = true;
6330      break;
6331    case 'U':
6332      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
6333      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
6334      Unsigned = true;
6335      break;
6336    case 'L':
6337      assert(HowLong <= 2 && "Can't have LLLL modifier");
6338      ++HowLong;
6339      break;
6340    }
6341  }
6342
6343  QualType Type;
6344
6345  // Read the base type.
6346  switch (*Str++) {
6347  default: llvm_unreachable("Unknown builtin type letter!");
6348  case 'v':
6349    assert(HowLong == 0 && !Signed && !Unsigned &&
6350           "Bad modifiers used with 'v'!");
6351    Type = Context.VoidTy;
6352    break;
6353  case 'f':
6354    assert(HowLong == 0 && !Signed && !Unsigned &&
6355           "Bad modifiers used with 'f'!");
6356    Type = Context.FloatTy;
6357    break;
6358  case 'd':
6359    assert(HowLong < 2 && !Signed && !Unsigned &&
6360           "Bad modifiers used with 'd'!");
6361    if (HowLong)
6362      Type = Context.LongDoubleTy;
6363    else
6364      Type = Context.DoubleTy;
6365    break;
6366  case 's':
6367    assert(HowLong == 0 && "Bad modifiers used with 's'!");
6368    if (Unsigned)
6369      Type = Context.UnsignedShortTy;
6370    else
6371      Type = Context.ShortTy;
6372    break;
6373  case 'i':
6374    if (HowLong == 3)
6375      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
6376    else if (HowLong == 2)
6377      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
6378    else if (HowLong == 1)
6379      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
6380    else
6381      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
6382    break;
6383  case 'c':
6384    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
6385    if (Signed)
6386      Type = Context.SignedCharTy;
6387    else if (Unsigned)
6388      Type = Context.UnsignedCharTy;
6389    else
6390      Type = Context.CharTy;
6391    break;
6392  case 'b': // boolean
6393    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
6394    Type = Context.BoolTy;
6395    break;
6396  case 'z':  // size_t.
6397    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
6398    Type = Context.getSizeType();
6399    break;
6400  case 'F':
6401    Type = Context.getCFConstantStringType();
6402    break;
6403  case 'G':
6404    Type = Context.getObjCIdType();
6405    break;
6406  case 'H':
6407    Type = Context.getObjCSelType();
6408    break;
6409  case 'a':
6410    Type = Context.getBuiltinVaListType();
6411    assert(!Type.isNull() && "builtin va list type not initialized!");
6412    break;
6413  case 'A':
6414    // This is a "reference" to a va_list; however, what exactly
6415    // this means depends on how va_list is defined. There are two
6416    // different kinds of va_list: ones passed by value, and ones
6417    // passed by reference.  An example of a by-value va_list is
6418    // x86, where va_list is a char*. An example of by-ref va_list
6419    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
6420    // we want this argument to be a char*&; for x86-64, we want
6421    // it to be a __va_list_tag*.
6422    Type = Context.getBuiltinVaListType();
6423    assert(!Type.isNull() && "builtin va list type not initialized!");
6424    if (Type->isArrayType())
6425      Type = Context.getArrayDecayedType(Type);
6426    else
6427      Type = Context.getLValueReferenceType(Type);
6428    break;
6429  case 'V': {
6430    char *End;
6431    unsigned NumElements = strtoul(Str, &End, 10);
6432    assert(End != Str && "Missing vector size");
6433    Str = End;
6434
6435    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
6436                                             RequiresICE, false);
6437    assert(!RequiresICE && "Can't require vector ICE");
6438
6439    // TODO: No way to make AltiVec vectors in builtins yet.
6440    Type = Context.getVectorType(ElementType, NumElements,
6441                                 VectorType::GenericVector);
6442    break;
6443  }
6444  case 'X': {
6445    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
6446                                             false);
6447    assert(!RequiresICE && "Can't require complex ICE");
6448    Type = Context.getComplexType(ElementType);
6449    break;
6450  }
6451  case 'Y' : {
6452    Type = Context.getPointerDiffType();
6453    break;
6454  }
6455  case 'P':
6456    Type = Context.getFILEType();
6457    if (Type.isNull()) {
6458      Error = ASTContext::GE_Missing_stdio;
6459      return QualType();
6460    }
6461    break;
6462  case 'J':
6463    if (Signed)
6464      Type = Context.getsigjmp_bufType();
6465    else
6466      Type = Context.getjmp_bufType();
6467
6468    if (Type.isNull()) {
6469      Error = ASTContext::GE_Missing_setjmp;
6470      return QualType();
6471    }
6472    break;
6473  case 'K':
6474    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'K'!");
6475    Type = Context.getucontext_tType();
6476
6477    if (Type.isNull()) {
6478      Error = ASTContext::GE_Missing_ucontext;
6479      return QualType();
6480    }
6481    break;
6482  }
6483
6484  // If there are modifiers and if we're allowed to parse them, go for it.
6485  Done = !AllowTypeModifiers;
6486  while (!Done) {
6487    switch (char c = *Str++) {
6488    default: Done = true; --Str; break;
6489    case '*':
6490    case '&': {
6491      // Both pointers and references can have their pointee types
6492      // qualified with an address space.
6493      char *End;
6494      unsigned AddrSpace = strtoul(Str, &End, 10);
6495      if (End != Str && AddrSpace != 0) {
6496        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
6497        Str = End;
6498      }
6499      if (c == '*')
6500        Type = Context.getPointerType(Type);
6501      else
6502        Type = Context.getLValueReferenceType(Type);
6503      break;
6504    }
6505    // FIXME: There's no way to have a built-in with an rvalue ref arg.
6506    case 'C':
6507      Type = Type.withConst();
6508      break;
6509    case 'D':
6510      Type = Context.getVolatileType(Type);
6511      break;
6512    case 'R':
6513      Type = Type.withRestrict();
6514      break;
6515    }
6516  }
6517
6518  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
6519         "Integer constant 'I' type must be an integer");
6520
6521  return Type;
6522}
6523
6524/// GetBuiltinType - Return the type for the specified builtin.
6525QualType ASTContext::GetBuiltinType(unsigned Id,
6526                                    GetBuiltinTypeError &Error,
6527                                    unsigned *IntegerConstantArgs) const {
6528  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
6529
6530  SmallVector<QualType, 8> ArgTypes;
6531
6532  bool RequiresICE = false;
6533  Error = GE_None;
6534  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
6535                                       RequiresICE, true);
6536  if (Error != GE_None)
6537    return QualType();
6538
6539  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
6540
6541  while (TypeStr[0] && TypeStr[0] != '.') {
6542    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
6543    if (Error != GE_None)
6544      return QualType();
6545
6546    // If this argument is required to be an IntegerConstantExpression and the
6547    // caller cares, fill in the bitmask we return.
6548    if (RequiresICE && IntegerConstantArgs)
6549      *IntegerConstantArgs |= 1 << ArgTypes.size();
6550
6551    // Do array -> pointer decay.  The builtin should use the decayed type.
6552    if (Ty->isArrayType())
6553      Ty = getArrayDecayedType(Ty);
6554
6555    ArgTypes.push_back(Ty);
6556  }
6557
6558  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
6559         "'.' should only occur at end of builtin type list!");
6560
6561  FunctionType::ExtInfo EI;
6562  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
6563
6564  bool Variadic = (TypeStr[0] == '.');
6565
6566  // We really shouldn't be making a no-proto type here, especially in C++.
6567  if (ArgTypes.empty() && Variadic)
6568    return getFunctionNoProtoType(ResType, EI);
6569
6570  FunctionProtoType::ExtProtoInfo EPI;
6571  EPI.ExtInfo = EI;
6572  EPI.Variadic = Variadic;
6573
6574  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(), EPI);
6575}
6576
6577GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
6578  GVALinkage External = GVA_StrongExternal;
6579
6580  Linkage L = FD->getLinkage();
6581  switch (L) {
6582  case NoLinkage:
6583  case InternalLinkage:
6584  case UniqueExternalLinkage:
6585    return GVA_Internal;
6586
6587  case ExternalLinkage:
6588    switch (FD->getTemplateSpecializationKind()) {
6589    case TSK_Undeclared:
6590    case TSK_ExplicitSpecialization:
6591      External = GVA_StrongExternal;
6592      break;
6593
6594    case TSK_ExplicitInstantiationDefinition:
6595      return GVA_ExplicitTemplateInstantiation;
6596
6597    case TSK_ExplicitInstantiationDeclaration:
6598    case TSK_ImplicitInstantiation:
6599      External = GVA_TemplateInstantiation;
6600      break;
6601    }
6602  }
6603
6604  if (!FD->isInlined())
6605    return External;
6606
6607  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
6608    // GNU or C99 inline semantics. Determine whether this symbol should be
6609    // externally visible.
6610    if (FD->isInlineDefinitionExternallyVisible())
6611      return External;
6612
6613    // C99 inline semantics, where the symbol is not externally visible.
6614    return GVA_C99Inline;
6615  }
6616
6617  // C++0x [temp.explicit]p9:
6618  //   [ Note: The intent is that an inline function that is the subject of
6619  //   an explicit instantiation declaration will still be implicitly
6620  //   instantiated when used so that the body can be considered for
6621  //   inlining, but that no out-of-line copy of the inline function would be
6622  //   generated in the translation unit. -- end note ]
6623  if (FD->getTemplateSpecializationKind()
6624                                       == TSK_ExplicitInstantiationDeclaration)
6625    return GVA_C99Inline;
6626
6627  return GVA_CXXInline;
6628}
6629
6630GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
6631  // If this is a static data member, compute the kind of template
6632  // specialization. Otherwise, this variable is not part of a
6633  // template.
6634  TemplateSpecializationKind TSK = TSK_Undeclared;
6635  if (VD->isStaticDataMember())
6636    TSK = VD->getTemplateSpecializationKind();
6637
6638  Linkage L = VD->getLinkage();
6639  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
6640      VD->getType()->getLinkage() == UniqueExternalLinkage)
6641    L = UniqueExternalLinkage;
6642
6643  switch (L) {
6644  case NoLinkage:
6645  case InternalLinkage:
6646  case UniqueExternalLinkage:
6647    return GVA_Internal;
6648
6649  case ExternalLinkage:
6650    switch (TSK) {
6651    case TSK_Undeclared:
6652    case TSK_ExplicitSpecialization:
6653      return GVA_StrongExternal;
6654
6655    case TSK_ExplicitInstantiationDeclaration:
6656      llvm_unreachable("Variable should not be instantiated");
6657      // Fall through to treat this like any other instantiation.
6658
6659    case TSK_ExplicitInstantiationDefinition:
6660      return GVA_ExplicitTemplateInstantiation;
6661
6662    case TSK_ImplicitInstantiation:
6663      return GVA_TemplateInstantiation;
6664    }
6665  }
6666
6667  llvm_unreachable("Invalid Linkage!");
6668}
6669
6670bool ASTContext::DeclMustBeEmitted(const Decl *D) {
6671  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
6672    if (!VD->isFileVarDecl())
6673      return false;
6674  } else if (!isa<FunctionDecl>(D))
6675    return false;
6676
6677  // Weak references don't produce any output by themselves.
6678  if (D->hasAttr<WeakRefAttr>())
6679    return false;
6680
6681  // Aliases and used decls are required.
6682  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
6683    return true;
6684
6685  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
6686    // Forward declarations aren't required.
6687    if (!FD->doesThisDeclarationHaveABody())
6688      return FD->doesDeclarationForceExternallyVisibleDefinition();
6689
6690    // Constructors and destructors are required.
6691    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
6692      return true;
6693
6694    // The key function for a class is required.
6695    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
6696      const CXXRecordDecl *RD = MD->getParent();
6697      if (MD->isOutOfLine() && RD->isDynamicClass()) {
6698        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
6699        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
6700          return true;
6701      }
6702    }
6703
6704    GVALinkage Linkage = GetGVALinkageForFunction(FD);
6705
6706    // static, static inline, always_inline, and extern inline functions can
6707    // always be deferred.  Normal inline functions can be deferred in C99/C++.
6708    // Implicit template instantiations can also be deferred in C++.
6709    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
6710        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
6711      return false;
6712    return true;
6713  }
6714
6715  const VarDecl *VD = cast<VarDecl>(D);
6716  assert(VD->isFileVarDecl() && "Expected file scoped var");
6717
6718  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
6719    return false;
6720
6721  // Structs that have non-trivial constructors or destructors are required.
6722
6723  // FIXME: Handle references.
6724  // FIXME: Be more selective about which constructors we care about.
6725  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
6726    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
6727      if (RD->hasDefinition() && !(RD->hasTrivialDefaultConstructor() &&
6728                                   RD->hasTrivialCopyConstructor() &&
6729                                   RD->hasTrivialMoveConstructor() &&
6730                                   RD->hasTrivialDestructor()))
6731        return true;
6732    }
6733  }
6734
6735  GVALinkage L = GetGVALinkageForVariable(VD);
6736  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
6737    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
6738      return false;
6739  }
6740
6741  return true;
6742}
6743
6744CallingConv ASTContext::getDefaultMethodCallConv() {
6745  // Pass through to the C++ ABI object
6746  return ABI->getDefaultMethodCallConv();
6747}
6748
6749bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
6750  // Pass through to the C++ ABI object
6751  return ABI->isNearlyEmpty(RD);
6752}
6753
6754MangleContext *ASTContext::createMangleContext() {
6755  switch (Target->getCXXABI()) {
6756  case CXXABI_ARM:
6757  case CXXABI_Itanium:
6758    return createItaniumMangleContext(*this, getDiagnostics());
6759  case CXXABI_Microsoft:
6760    return createMicrosoftMangleContext(*this, getDiagnostics());
6761  }
6762  llvm_unreachable("Unsupported ABI");
6763}
6764
6765CXXABI::~CXXABI() {}
6766
6767size_t ASTContext::getSideTableAllocatedMemory() const {
6768  return ASTRecordLayouts.getMemorySize()
6769    + llvm::capacity_in_bytes(ObjCLayouts)
6770    + llvm::capacity_in_bytes(KeyFunctions)
6771    + llvm::capacity_in_bytes(ObjCImpls)
6772    + llvm::capacity_in_bytes(BlockVarCopyInits)
6773    + llvm::capacity_in_bytes(DeclAttrs)
6774    + llvm::capacity_in_bytes(InstantiatedFromStaticDataMember)
6775    + llvm::capacity_in_bytes(InstantiatedFromUsingDecl)
6776    + llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl)
6777    + llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl)
6778    + llvm::capacity_in_bytes(OverriddenMethods)
6779    + llvm::capacity_in_bytes(Types)
6780    + llvm::capacity_in_bytes(VariableArrayTypes)
6781    + llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
6782}
6783
6784void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
6785  ParamIndices[D] = index;
6786}
6787
6788unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
6789  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
6790  assert(I != ParamIndices.end() &&
6791         "ParmIndices lacks entry set by ParmVarDecl");
6792  return I->second;
6793}
6794