ASTContext.cpp revision 561d3abc881033776ece385a01a510e1cbc1fa92 
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/SourceManager.h"
28#include "clang/Basic/TargetInfo.h"
29#include "llvm/ADT/SmallString.h"
30#include "llvm/ADT/StringExtras.h"
31#include "llvm/Support/MathExtras.h"
32#include "llvm/Support/raw_ostream.h"
33#include "llvm/Support/Capacity.h"
34#include "CXXABI.h"
35#include <map>
36
37using namespace clang;
38
39unsigned ASTContext::NumImplicitDefaultConstructors;
40unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
41unsigned ASTContext::NumImplicitCopyConstructors;
42unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
43unsigned ASTContext::NumImplicitMoveConstructors;
44unsigned ASTContext::NumImplicitMoveConstructorsDeclared;
45unsigned ASTContext::NumImplicitCopyAssignmentOperators;
46unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
47unsigned ASTContext::NumImplicitMoveAssignmentOperators;
48unsigned ASTContext::NumImplicitMoveAssignmentOperatorsDeclared;
49unsigned ASTContext::NumImplicitDestructors;
50unsigned ASTContext::NumImplicitDestructorsDeclared;
51
52enum FloatingRank {
53  HalfRank, FloatRank, DoubleRank, LongDoubleRank
54};
55
56void
57ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
58                                               TemplateTemplateParmDecl *Parm) {
59  ID.AddInteger(Parm->getDepth());
60  ID.AddInteger(Parm->getPosition());
61  ID.AddBoolean(Parm->isParameterPack());
62
63  TemplateParameterList *Params = Parm->getTemplateParameters();
64  ID.AddInteger(Params->size());
65  for (TemplateParameterList::const_iterator P = Params->begin(),
66                                          PEnd = Params->end();
67       P != PEnd; ++P) {
68    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
69      ID.AddInteger(0);
70      ID.AddBoolean(TTP->isParameterPack());
71      continue;
72    }
73
74    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
75      ID.AddInteger(1);
76      ID.AddBoolean(NTTP->isParameterPack());
77      ID.AddPointer(NTTP->getType().getAsOpaquePtr());
78      if (NTTP->isExpandedParameterPack()) {
79        ID.AddBoolean(true);
80        ID.AddInteger(NTTP->getNumExpansionTypes());
81        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I)
82          ID.AddPointer(NTTP->getExpansionType(I).getAsOpaquePtr());
83      } else
84        ID.AddBoolean(false);
85      continue;
86    }
87
88    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
89    ID.AddInteger(2);
90    Profile(ID, TTP);
91  }
92}
93
94TemplateTemplateParmDecl *
95ASTContext::getCanonicalTemplateTemplateParmDecl(
96                                          TemplateTemplateParmDecl *TTP) const {
97  // Check if we already have a canonical template template parameter.
98  llvm::FoldingSetNodeID ID;
99  CanonicalTemplateTemplateParm::Profile(ID, TTP);
100  void *InsertPos = 0;
101  CanonicalTemplateTemplateParm *Canonical
102    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
103  if (Canonical)
104    return Canonical->getParam();
105
106  // Build a canonical template parameter list.
107  TemplateParameterList *Params = TTP->getTemplateParameters();
108  SmallVector<NamedDecl *, 4> CanonParams;
109  CanonParams.reserve(Params->size());
110  for (TemplateParameterList::const_iterator P = Params->begin(),
111                                          PEnd = Params->end();
112       P != PEnd; ++P) {
113    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
114      CanonParams.push_back(
115                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
116                                               SourceLocation(),
117                                               SourceLocation(),
118                                               TTP->getDepth(),
119                                               TTP->getIndex(), 0, false,
120                                               TTP->isParameterPack()));
121    else if (NonTypeTemplateParmDecl *NTTP
122             = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
123      QualType T = getCanonicalType(NTTP->getType());
124      TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
125      NonTypeTemplateParmDecl *Param;
126      if (NTTP->isExpandedParameterPack()) {
127        SmallVector<QualType, 2> ExpandedTypes;
128        SmallVector<TypeSourceInfo *, 2> ExpandedTInfos;
129        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
130          ExpandedTypes.push_back(getCanonicalType(NTTP->getExpansionType(I)));
131          ExpandedTInfos.push_back(
132                                getTrivialTypeSourceInfo(ExpandedTypes.back()));
133        }
134
135        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
136                                                SourceLocation(),
137                                                SourceLocation(),
138                                                NTTP->getDepth(),
139                                                NTTP->getPosition(), 0,
140                                                T,
141                                                TInfo,
142                                                ExpandedTypes.data(),
143                                                ExpandedTypes.size(),
144                                                ExpandedTInfos.data());
145      } else {
146        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
147                                                SourceLocation(),
148                                                SourceLocation(),
149                                                NTTP->getDepth(),
150                                                NTTP->getPosition(), 0,
151                                                T,
152                                                NTTP->isParameterPack(),
153                                                TInfo);
154      }
155      CanonParams.push_back(Param);
156
157    } else
158      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
159                                           cast<TemplateTemplateParmDecl>(*P)));
160  }
161
162  TemplateTemplateParmDecl *CanonTTP
163    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
164                                       SourceLocation(), TTP->getDepth(),
165                                       TTP->getPosition(),
166                                       TTP->isParameterPack(),
167                                       0,
168                         TemplateParameterList::Create(*this, SourceLocation(),
169                                                       SourceLocation(),
170                                                       CanonParams.data(),
171                                                       CanonParams.size(),
172                                                       SourceLocation()));
173
174  // Get the new insert position for the node we care about.
175  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
176  assert(Canonical == 0 && "Shouldn't be in the map!");
177  (void)Canonical;
178
179  // Create the canonical template template parameter entry.
180  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
181  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
182  return CanonTTP;
183}
184
185CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
186  if (!LangOpts.CPlusPlus) return 0;
187
188  switch (T.getCXXABI()) {
189  case CXXABI_ARM:
190    return CreateARMCXXABI(*this);
191  case CXXABI_Itanium:
192    return CreateItaniumCXXABI(*this);
193  case CXXABI_Microsoft:
194    return CreateMicrosoftCXXABI(*this);
195  }
196  return 0;
197}
198
199static const LangAS::Map *getAddressSpaceMap(const TargetInfo &T,
200                                             const LangOptions &LOpts) {
201  if (LOpts.FakeAddressSpaceMap) {
202    // The fake address space map must have a distinct entry for each
203    // language-specific address space.
204    static const unsigned FakeAddrSpaceMap[] = {
205      1, // opencl_global
206      2, // opencl_local
207      3  // opencl_constant
208    };
209    return &FakeAddrSpaceMap;
210  } else {
211    return &T.getAddressSpaceMap();
212  }
213}
214
215ASTContext::ASTContext(LangOptions& LOpts, SourceManager &SM,
216                       const TargetInfo *t,
217                       IdentifierTable &idents, SelectorTable &sels,
218                       Builtin::Context &builtins,
219                       unsigned size_reserve,
220                       bool DelayInitialization)
221  : FunctionProtoTypes(this_()),
222    TemplateSpecializationTypes(this_()),
223    DependentTemplateSpecializationTypes(this_()),
224    SubstTemplateTemplateParmPacks(this_()),
225    GlobalNestedNameSpecifier(0),
226    Int128Decl(0), UInt128Decl(0),
227    ObjCIdDecl(0), ObjCSelDecl(0), ObjCClassDecl(0),
228    CFConstantStringTypeDecl(0), ObjCInstanceTypeDecl(0),
229    FILEDecl(0),
230    jmp_bufDecl(0), sigjmp_bufDecl(0), ucontext_tDecl(0),
231    BlockDescriptorType(0), BlockDescriptorExtendedType(0),
232    cudaConfigureCallDecl(0),
233    NullTypeSourceInfo(QualType()),
234    FirstLocalImport(), LastLocalImport(),
235    SourceMgr(SM), LangOpts(LOpts),
236    AddrSpaceMap(0), Target(t), PrintingPolicy(LOpts),
237    Idents(idents), Selectors(sels),
238    BuiltinInfo(builtins),
239    DeclarationNames(*this),
240    ExternalSource(0), Listener(0),
241    LastSDM(0, 0),
242    UniqueBlockByRefTypeID(0)
243{
244  if (size_reserve > 0) Types.reserve(size_reserve);
245  TUDecl = TranslationUnitDecl::Create(*this);
246
247  if (!DelayInitialization) {
248    assert(t && "No target supplied for ASTContext initialization");
249    InitBuiltinTypes(*t);
250  }
251}
252
253ASTContext::~ASTContext() {
254  // Release the DenseMaps associated with DeclContext objects.
255  // FIXME: Is this the ideal solution?
256  ReleaseDeclContextMaps();
257
258  // Call all of the deallocation functions.
259  for (unsigned I = 0, N = Deallocations.size(); I != N; ++I)
260    Deallocations[I].first(Deallocations[I].second);
261
262  // Release all of the memory associated with overridden C++ methods.
263  for (llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::iterator
264         OM = OverriddenMethods.begin(), OMEnd = OverriddenMethods.end();
265       OM != OMEnd; ++OM)
266    OM->second.Destroy();
267
268  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
269  // because they can contain DenseMaps.
270  for (llvm::DenseMap<const ObjCContainerDecl*,
271       const ASTRecordLayout*>::iterator
272       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
273    // Increment in loop to prevent using deallocated memory.
274    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
275      R->Destroy(*this);
276
277  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
278       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
279    // Increment in loop to prevent using deallocated memory.
280    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
281      R->Destroy(*this);
282  }
283
284  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
285                                                    AEnd = DeclAttrs.end();
286       A != AEnd; ++A)
287    A->second->~AttrVec();
288}
289
290void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
291  Deallocations.push_back(std::make_pair(Callback, Data));
292}
293
294void
295ASTContext::setExternalSource(llvm::OwningPtr<ExternalASTSource> &Source) {
296  ExternalSource.reset(Source.take());
297}
298
299void ASTContext::PrintStats() const {
300  llvm::errs() << "\n*** AST Context Stats:\n";
301  llvm::errs() << "  " << Types.size() << " types total.\n";
302
303  unsigned counts[] = {
304#define TYPE(Name, Parent) 0,
305#define ABSTRACT_TYPE(Name, Parent)
306#include "clang/AST/TypeNodes.def"
307    0 // Extra
308  };
309
310  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
311    Type *T = Types[i];
312    counts[(unsigned)T->getTypeClass()]++;
313  }
314
315  unsigned Idx = 0;
316  unsigned TotalBytes = 0;
317#define TYPE(Name, Parent)                                              \
318  if (counts[Idx])                                                      \
319    llvm::errs() << "    " << counts[Idx] << " " << #Name               \
320                 << " types\n";                                         \
321  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
322  ++Idx;
323#define ABSTRACT_TYPE(Name, Parent)
324#include "clang/AST/TypeNodes.def"
325
326  llvm::errs() << "Total bytes = " << TotalBytes << "\n";
327
328  // Implicit special member functions.
329  llvm::errs() << NumImplicitDefaultConstructorsDeclared << "/"
330               << NumImplicitDefaultConstructors
331               << " implicit default constructors created\n";
332  llvm::errs() << NumImplicitCopyConstructorsDeclared << "/"
333               << NumImplicitCopyConstructors
334               << " implicit copy constructors created\n";
335  if (getLangOptions().CPlusPlus)
336    llvm::errs() << NumImplicitMoveConstructorsDeclared << "/"
337                 << NumImplicitMoveConstructors
338                 << " implicit move constructors created\n";
339  llvm::errs() << NumImplicitCopyAssignmentOperatorsDeclared << "/"
340               << NumImplicitCopyAssignmentOperators
341               << " implicit copy assignment operators created\n";
342  if (getLangOptions().CPlusPlus)
343    llvm::errs() << NumImplicitMoveAssignmentOperatorsDeclared << "/"
344                 << NumImplicitMoveAssignmentOperators
345                 << " implicit move assignment operators created\n";
346  llvm::errs() << NumImplicitDestructorsDeclared << "/"
347               << NumImplicitDestructors
348               << " implicit destructors created\n";
349
350  if (ExternalSource.get()) {
351    llvm::errs() << "\n";
352    ExternalSource->PrintStats();
353  }
354
355  BumpAlloc.PrintStats();
356}
357
358TypedefDecl *ASTContext::getInt128Decl() const {
359  if (!Int128Decl) {
360    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(Int128Ty);
361    Int128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
362                                     getTranslationUnitDecl(),
363                                     SourceLocation(),
364                                     SourceLocation(),
365                                     &Idents.get("__int128_t"),
366                                     TInfo);
367  }
368
369  return Int128Decl;
370}
371
372TypedefDecl *ASTContext::getUInt128Decl() const {
373  if (!UInt128Decl) {
374    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(UnsignedInt128Ty);
375    UInt128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
376                                     getTranslationUnitDecl(),
377                                     SourceLocation(),
378                                     SourceLocation(),
379                                     &Idents.get("__uint128_t"),
380                                     TInfo);
381  }
382
383  return UInt128Decl;
384}
385
386void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
387  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
388  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
389  Types.push_back(Ty);
390}
391
392void ASTContext::InitBuiltinTypes(const TargetInfo &Target) {
393  assert((!this->Target || this->Target == &Target) &&
394         "Incorrect target reinitialization");
395  assert(VoidTy.isNull() && "Context reinitialized?");
396
397  this->Target = &Target;
398
399  ABI.reset(createCXXABI(Target));
400  AddrSpaceMap = getAddressSpaceMap(Target, LangOpts);
401
402  // C99 6.2.5p19.
403  InitBuiltinType(VoidTy,              BuiltinType::Void);
404
405  // C99 6.2.5p2.
406  InitBuiltinType(BoolTy,              BuiltinType::Bool);
407  // C99 6.2.5p3.
408  if (LangOpts.CharIsSigned)
409    InitBuiltinType(CharTy,            BuiltinType::Char_S);
410  else
411    InitBuiltinType(CharTy,            BuiltinType::Char_U);
412  // C99 6.2.5p4.
413  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
414  InitBuiltinType(ShortTy,             BuiltinType::Short);
415  InitBuiltinType(IntTy,               BuiltinType::Int);
416  InitBuiltinType(LongTy,              BuiltinType::Long);
417  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
418
419  // C99 6.2.5p6.
420  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
421  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
422  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
423  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
424  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
425
426  // C99 6.2.5p10.
427  InitBuiltinType(FloatTy,             BuiltinType::Float);
428  InitBuiltinType(DoubleTy,            BuiltinType::Double);
429  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
430
431  // GNU extension, 128-bit integers.
432  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
433  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
434
435  if (LangOpts.CPlusPlus) { // C++ 3.9.1p5
436    if (TargetInfo::isTypeSigned(Target.getWCharType()))
437      InitBuiltinType(WCharTy,           BuiltinType::WChar_S);
438    else  // -fshort-wchar makes wchar_t be unsigned.
439      InitBuiltinType(WCharTy,           BuiltinType::WChar_U);
440  } else // C99
441    WCharTy = getFromTargetType(Target.getWCharType());
442
443  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
444    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
445  else // C99
446    Char16Ty = getFromTargetType(Target.getChar16Type());
447
448  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
449    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
450  else // C99
451    Char32Ty = getFromTargetType(Target.getChar32Type());
452
453  // Placeholder type for type-dependent expressions whose type is
454  // completely unknown. No code should ever check a type against
455  // DependentTy and users should never see it; however, it is here to
456  // help diagnose failures to properly check for type-dependent
457  // expressions.
458  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
459
460  // Placeholder type for functions.
461  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
462
463  // Placeholder type for bound members.
464  InitBuiltinType(BoundMemberTy,       BuiltinType::BoundMember);
465
466  // Placeholder type for pseudo-objects.
467  InitBuiltinType(PseudoObjectTy,      BuiltinType::PseudoObject);
468
469  // "any" type; useful for debugger-like clients.
470  InitBuiltinType(UnknownAnyTy,        BuiltinType::UnknownAny);
471
472  // Placeholder type for unbridged ARC casts.
473  InitBuiltinType(ARCUnbridgedCastTy,  BuiltinType::ARCUnbridgedCast);
474
475  // C99 6.2.5p11.
476  FloatComplexTy      = getComplexType(FloatTy);
477  DoubleComplexTy     = getComplexType(DoubleTy);
478  LongDoubleComplexTy = getComplexType(LongDoubleTy);
479
480  BuiltinVaListType = QualType();
481
482  // Builtin types for 'id', 'Class', and 'SEL'.
483  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
484  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
485  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
486
487  ObjCConstantStringType = QualType();
488
489  // void * type
490  VoidPtrTy = getPointerType(VoidTy);
491
492  // nullptr type (C++0x 2.14.7)
493  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
494
495  // half type (OpenCL 6.1.1.1) / ARM NEON __fp16
496  InitBuiltinType(HalfTy, BuiltinType::Half);
497}
498
499DiagnosticsEngine &ASTContext::getDiagnostics() const {
500  return SourceMgr.getDiagnostics();
501}
502
503AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
504  AttrVec *&Result = DeclAttrs[D];
505  if (!Result) {
506    void *Mem = Allocate(sizeof(AttrVec));
507    Result = new (Mem) AttrVec;
508  }
509
510  return *Result;
511}
512
513/// \brief Erase the attributes corresponding to the given declaration.
514void ASTContext::eraseDeclAttrs(const Decl *D) {
515  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
516  if (Pos != DeclAttrs.end()) {
517    Pos->second->~AttrVec();
518    DeclAttrs.erase(Pos);
519  }
520}
521
522MemberSpecializationInfo *
523ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
524  assert(Var->isStaticDataMember() && "Not a static data member");
525  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
526    = InstantiatedFromStaticDataMember.find(Var);
527  if (Pos == InstantiatedFromStaticDataMember.end())
528    return 0;
529
530  return Pos->second;
531}
532
533void
534ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
535                                                TemplateSpecializationKind TSK,
536                                          SourceLocation PointOfInstantiation) {
537  assert(Inst->isStaticDataMember() && "Not a static data member");
538  assert(Tmpl->isStaticDataMember() && "Not a static data member");
539  assert(!InstantiatedFromStaticDataMember[Inst] &&
540         "Already noted what static data member was instantiated from");
541  InstantiatedFromStaticDataMember[Inst]
542    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
543}
544
545FunctionDecl *ASTContext::getClassScopeSpecializationPattern(
546                                                     const FunctionDecl *FD){
547  assert(FD && "Specialization is 0");
548  llvm::DenseMap<const FunctionDecl*, FunctionDecl *>::const_iterator Pos
549    = ClassScopeSpecializationPattern.find(FD);
550  if (Pos == ClassScopeSpecializationPattern.end())
551    return 0;
552
553  return Pos->second;
554}
555
556void ASTContext::setClassScopeSpecializationPattern(FunctionDecl *FD,
557                                        FunctionDecl *Pattern) {
558  assert(FD && "Specialization is 0");
559  assert(Pattern && "Class scope specialization pattern is 0");
560  ClassScopeSpecializationPattern[FD] = Pattern;
561}
562
563NamedDecl *
564ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
565  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
566    = InstantiatedFromUsingDecl.find(UUD);
567  if (Pos == InstantiatedFromUsingDecl.end())
568    return 0;
569
570  return Pos->second;
571}
572
573void
574ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
575  assert((isa<UsingDecl>(Pattern) ||
576          isa<UnresolvedUsingValueDecl>(Pattern) ||
577          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
578         "pattern decl is not a using decl");
579  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
580  InstantiatedFromUsingDecl[Inst] = Pattern;
581}
582
583UsingShadowDecl *
584ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
585  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
586    = InstantiatedFromUsingShadowDecl.find(Inst);
587  if (Pos == InstantiatedFromUsingShadowDecl.end())
588    return 0;
589
590  return Pos->second;
591}
592
593void
594ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
595                                               UsingShadowDecl *Pattern) {
596  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
597  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
598}
599
600FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
601  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
602    = InstantiatedFromUnnamedFieldDecl.find(Field);
603  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
604    return 0;
605
606  return Pos->second;
607}
608
609void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
610                                                     FieldDecl *Tmpl) {
611  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
612  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
613  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
614         "Already noted what unnamed field was instantiated from");
615
616  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
617}
618
619bool ASTContext::ZeroBitfieldFollowsNonBitfield(const FieldDecl *FD,
620                                    const FieldDecl *LastFD) const {
621  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
622          FD->getBitWidthValue(*this) == 0);
623}
624
625bool ASTContext::ZeroBitfieldFollowsBitfield(const FieldDecl *FD,
626                                             const FieldDecl *LastFD) const {
627  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
628          FD->getBitWidthValue(*this) == 0 &&
629          LastFD->getBitWidthValue(*this) != 0);
630}
631
632bool ASTContext::BitfieldFollowsBitfield(const FieldDecl *FD,
633                                         const FieldDecl *LastFD) const {
634  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
635          FD->getBitWidthValue(*this) &&
636          LastFD->getBitWidthValue(*this));
637}
638
639bool ASTContext::NonBitfieldFollowsBitfield(const FieldDecl *FD,
640                                         const FieldDecl *LastFD) const {
641  return (!FD->isBitField() && LastFD && LastFD->isBitField() &&
642          LastFD->getBitWidthValue(*this));
643}
644
645bool ASTContext::BitfieldFollowsNonBitfield(const FieldDecl *FD,
646                                             const FieldDecl *LastFD) const {
647  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
648          FD->getBitWidthValue(*this));
649}
650
651ASTContext::overridden_cxx_method_iterator
652ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
653  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
654    = OverriddenMethods.find(Method);
655  if (Pos == OverriddenMethods.end())
656    return 0;
657
658  return Pos->second.begin();
659}
660
661ASTContext::overridden_cxx_method_iterator
662ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
663  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
664    = OverriddenMethods.find(Method);
665  if (Pos == OverriddenMethods.end())
666    return 0;
667
668  return Pos->second.end();
669}
670
671unsigned
672ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
673  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
674    = OverriddenMethods.find(Method);
675  if (Pos == OverriddenMethods.end())
676    return 0;
677
678  return Pos->second.size();
679}
680
681void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
682                                     const CXXMethodDecl *Overridden) {
683  OverriddenMethods[Method].push_back(Overridden);
684}
685
686void ASTContext::addedLocalImportDecl(ImportDecl *Import) {
687  assert(!Import->NextLocalImport && "Import declaration already in the chain");
688  assert(!Import->isFromASTFile() && "Non-local import declaration");
689  if (!FirstLocalImport) {
690    FirstLocalImport = Import;
691    LastLocalImport = Import;
692    return;
693  }
694
695  LastLocalImport->NextLocalImport = Import;
696  LastLocalImport = Import;
697}
698
699//===----------------------------------------------------------------------===//
700//                         Type Sizing and Analysis
701//===----------------------------------------------------------------------===//
702
703/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
704/// scalar floating point type.
705const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
706  const BuiltinType *BT = T->getAs<BuiltinType>();
707  assert(BT && "Not a floating point type!");
708  switch (BT->getKind()) {
709  default: llvm_unreachable("Not a floating point type!");
710  case BuiltinType::Half:       return Target->getHalfFormat();
711  case BuiltinType::Float:      return Target->getFloatFormat();
712  case BuiltinType::Double:     return Target->getDoubleFormat();
713  case BuiltinType::LongDouble: return Target->getLongDoubleFormat();
714  }
715}
716
717/// getDeclAlign - Return a conservative estimate of the alignment of the
718/// specified decl.  Note that bitfields do not have a valid alignment, so
719/// this method will assert on them.
720/// If @p RefAsPointee, references are treated like their underlying type
721/// (for alignof), else they're treated like pointers (for CodeGen).
722CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) const {
723  unsigned Align = Target->getCharWidth();
724
725  bool UseAlignAttrOnly = false;
726  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
727    Align = AlignFromAttr;
728
729    // __attribute__((aligned)) can increase or decrease alignment
730    // *except* on a struct or struct member, where it only increases
731    // alignment unless 'packed' is also specified.
732    //
733    // It is an error for alignas to decrease alignment, so we can
734    // ignore that possibility;  Sema should diagnose it.
735    if (isa<FieldDecl>(D)) {
736      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
737        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
738    } else {
739      UseAlignAttrOnly = true;
740    }
741  }
742  else if (isa<FieldDecl>(D))
743      UseAlignAttrOnly =
744        D->hasAttr<PackedAttr>() ||
745        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
746
747  // If we're using the align attribute only, just ignore everything
748  // else about the declaration and its type.
749  if (UseAlignAttrOnly) {
750    // do nothing
751
752  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
753    QualType T = VD->getType();
754    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
755      if (RefAsPointee)
756        T = RT->getPointeeType();
757      else
758        T = getPointerType(RT->getPointeeType());
759    }
760    if (!T->isIncompleteType() && !T->isFunctionType()) {
761      // Adjust alignments of declarations with array type by the
762      // large-array alignment on the target.
763      unsigned MinWidth = Target->getLargeArrayMinWidth();
764      const ArrayType *arrayType;
765      if (MinWidth && (arrayType = getAsArrayType(T))) {
766        if (isa<VariableArrayType>(arrayType))
767          Align = std::max(Align, Target->getLargeArrayAlign());
768        else if (isa<ConstantArrayType>(arrayType) &&
769                 MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
770          Align = std::max(Align, Target->getLargeArrayAlign());
771
772        // Walk through any array types while we're at it.
773        T = getBaseElementType(arrayType);
774      }
775      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
776    }
777
778    // Fields can be subject to extra alignment constraints, like if
779    // the field is packed, the struct is packed, or the struct has a
780    // a max-field-alignment constraint (#pragma pack).  So calculate
781    // the actual alignment of the field within the struct, and then
782    // (as we're expected to) constrain that by the alignment of the type.
783    if (const FieldDecl *field = dyn_cast<FieldDecl>(VD)) {
784      // So calculate the alignment of the field.
785      const ASTRecordLayout &layout = getASTRecordLayout(field->getParent());
786
787      // Start with the record's overall alignment.
788      unsigned fieldAlign = toBits(layout.getAlignment());
789
790      // Use the GCD of that and the offset within the record.
791      uint64_t offset = layout.getFieldOffset(field->getFieldIndex());
792      if (offset > 0) {
793        // Alignment is always a power of 2, so the GCD will be a power of 2,
794        // which means we get to do this crazy thing instead of Euclid's.
795        uint64_t lowBitOfOffset = offset & (~offset + 1);
796        if (lowBitOfOffset < fieldAlign)
797          fieldAlign = static_cast<unsigned>(lowBitOfOffset);
798      }
799
800      Align = std::min(Align, fieldAlign);
801    }
802  }
803
804  return toCharUnitsFromBits(Align);
805}
806
807std::pair<CharUnits, CharUnits>
808ASTContext::getTypeInfoInChars(const Type *T) const {
809  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
810  return std::make_pair(toCharUnitsFromBits(Info.first),
811                        toCharUnitsFromBits(Info.second));
812}
813
814std::pair<CharUnits, CharUnits>
815ASTContext::getTypeInfoInChars(QualType T) const {
816  return getTypeInfoInChars(T.getTypePtr());
817}
818
819/// getTypeSize - Return the size of the specified type, in bits.  This method
820/// does not work on incomplete types.
821///
822/// FIXME: Pointers into different addr spaces could have different sizes and
823/// alignment requirements: getPointerInfo should take an AddrSpace, this
824/// should take a QualType, &c.
825std::pair<uint64_t, unsigned>
826ASTContext::getTypeInfo(const Type *T) const {
827  uint64_t Width=0;
828  unsigned Align=8;
829  switch (T->getTypeClass()) {
830#define TYPE(Class, Base)
831#define ABSTRACT_TYPE(Class, Base)
832#define NON_CANONICAL_TYPE(Class, Base)
833#define DEPENDENT_TYPE(Class, Base) case Type::Class:
834#include "clang/AST/TypeNodes.def"
835    llvm_unreachable("Should not see dependent types");
836    break;
837
838  case Type::FunctionNoProto:
839  case Type::FunctionProto:
840    // GCC extension: alignof(function) = 32 bits
841    Width = 0;
842    Align = 32;
843    break;
844
845  case Type::IncompleteArray:
846  case Type::VariableArray:
847    Width = 0;
848    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
849    break;
850
851  case Type::ConstantArray: {
852    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
853
854    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
855    uint64_t Size = CAT->getSize().getZExtValue();
856    assert((Size == 0 || EltInfo.first <= (uint64_t)(-1)/Size) && "Overflow in array type bit size evaluation");
857    Width = EltInfo.first*Size;
858    Align = EltInfo.second;
859    Width = llvm::RoundUpToAlignment(Width, Align);
860    break;
861  }
862  case Type::ExtVector:
863  case Type::Vector: {
864    const VectorType *VT = cast<VectorType>(T);
865    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
866    Width = EltInfo.first*VT->getNumElements();
867    Align = Width;
868    // If the alignment is not a power of 2, round up to the next power of 2.
869    // This happens for non-power-of-2 length vectors.
870    if (Align & (Align-1)) {
871      Align = llvm::NextPowerOf2(Align);
872      Width = llvm::RoundUpToAlignment(Width, Align);
873    }
874    break;
875  }
876
877  case Type::Builtin:
878    switch (cast<BuiltinType>(T)->getKind()) {
879    default: llvm_unreachable("Unknown builtin type!");
880    case BuiltinType::Void:
881      // GCC extension: alignof(void) = 8 bits.
882      Width = 0;
883      Align = 8;
884      break;
885
886    case BuiltinType::Bool:
887      Width = Target->getBoolWidth();
888      Align = Target->getBoolAlign();
889      break;
890    case BuiltinType::Char_S:
891    case BuiltinType::Char_U:
892    case BuiltinType::UChar:
893    case BuiltinType::SChar:
894      Width = Target->getCharWidth();
895      Align = Target->getCharAlign();
896      break;
897    case BuiltinType::WChar_S:
898    case BuiltinType::WChar_U:
899      Width = Target->getWCharWidth();
900      Align = Target->getWCharAlign();
901      break;
902    case BuiltinType::Char16:
903      Width = Target->getChar16Width();
904      Align = Target->getChar16Align();
905      break;
906    case BuiltinType::Char32:
907      Width = Target->getChar32Width();
908      Align = Target->getChar32Align();
909      break;
910    case BuiltinType::UShort:
911    case BuiltinType::Short:
912      Width = Target->getShortWidth();
913      Align = Target->getShortAlign();
914      break;
915    case BuiltinType::UInt:
916    case BuiltinType::Int:
917      Width = Target->getIntWidth();
918      Align = Target->getIntAlign();
919      break;
920    case BuiltinType::ULong:
921    case BuiltinType::Long:
922      Width = Target->getLongWidth();
923      Align = Target->getLongAlign();
924      break;
925    case BuiltinType::ULongLong:
926    case BuiltinType::LongLong:
927      Width = Target->getLongLongWidth();
928      Align = Target->getLongLongAlign();
929      break;
930    case BuiltinType::Int128:
931    case BuiltinType::UInt128:
932      Width = 128;
933      Align = 128; // int128_t is 128-bit aligned on all targets.
934      break;
935    case BuiltinType::Half:
936      Width = Target->getHalfWidth();
937      Align = Target->getHalfAlign();
938      break;
939    case BuiltinType::Float:
940      Width = Target->getFloatWidth();
941      Align = Target->getFloatAlign();
942      break;
943    case BuiltinType::Double:
944      Width = Target->getDoubleWidth();
945      Align = Target->getDoubleAlign();
946      break;
947    case BuiltinType::LongDouble:
948      Width = Target->getLongDoubleWidth();
949      Align = Target->getLongDoubleAlign();
950      break;
951    case BuiltinType::NullPtr:
952      Width = Target->getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
953      Align = Target->getPointerAlign(0); //   == sizeof(void*)
954      break;
955    case BuiltinType::ObjCId:
956    case BuiltinType::ObjCClass:
957    case BuiltinType::ObjCSel:
958      Width = Target->getPointerWidth(0);
959      Align = Target->getPointerAlign(0);
960      break;
961    }
962    break;
963  case Type::ObjCObjectPointer:
964    Width = Target->getPointerWidth(0);
965    Align = Target->getPointerAlign(0);
966    break;
967  case Type::BlockPointer: {
968    unsigned AS = getTargetAddressSpace(
969        cast<BlockPointerType>(T)->getPointeeType());
970    Width = Target->getPointerWidth(AS);
971    Align = Target->getPointerAlign(AS);
972    break;
973  }
974  case Type::LValueReference:
975  case Type::RValueReference: {
976    // alignof and sizeof should never enter this code path here, so we go
977    // the pointer route.
978    unsigned AS = getTargetAddressSpace(
979        cast<ReferenceType>(T)->getPointeeType());
980    Width = Target->getPointerWidth(AS);
981    Align = Target->getPointerAlign(AS);
982    break;
983  }
984  case Type::Pointer: {
985    unsigned AS = getTargetAddressSpace(cast<PointerType>(T)->getPointeeType());
986    Width = Target->getPointerWidth(AS);
987    Align = Target->getPointerAlign(AS);
988    break;
989  }
990  case Type::MemberPointer: {
991    const MemberPointerType *MPT = cast<MemberPointerType>(T);
992    std::pair<uint64_t, unsigned> PtrDiffInfo =
993      getTypeInfo(getPointerDiffType());
994    Width = PtrDiffInfo.first * ABI->getMemberPointerSize(MPT);
995    Align = PtrDiffInfo.second;
996    break;
997  }
998  case Type::Complex: {
999    // Complex types have the same alignment as their elements, but twice the
1000    // size.
1001    std::pair<uint64_t, unsigned> EltInfo =
1002      getTypeInfo(cast<ComplexType>(T)->getElementType());
1003    Width = EltInfo.first*2;
1004    Align = EltInfo.second;
1005    break;
1006  }
1007  case Type::ObjCObject:
1008    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
1009  case Type::ObjCInterface: {
1010    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
1011    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
1012    Width = toBits(Layout.getSize());
1013    Align = toBits(Layout.getAlignment());
1014    break;
1015  }
1016  case Type::Record:
1017  case Type::Enum: {
1018    const TagType *TT = cast<TagType>(T);
1019
1020    if (TT->getDecl()->isInvalidDecl()) {
1021      Width = 8;
1022      Align = 8;
1023      break;
1024    }
1025
1026    if (const EnumType *ET = dyn_cast<EnumType>(TT))
1027      return getTypeInfo(ET->getDecl()->getIntegerType());
1028
1029    const RecordType *RT = cast<RecordType>(TT);
1030    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
1031    Width = toBits(Layout.getSize());
1032    Align = toBits(Layout.getAlignment());
1033    break;
1034  }
1035
1036  case Type::SubstTemplateTypeParm:
1037    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
1038                       getReplacementType().getTypePtr());
1039
1040  case Type::Auto: {
1041    const AutoType *A = cast<AutoType>(T);
1042    assert(A->isDeduced() && "Cannot request the size of a dependent type");
1043    return getTypeInfo(A->getDeducedType().getTypePtr());
1044  }
1045
1046  case Type::Paren:
1047    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
1048
1049  case Type::Typedef: {
1050    const TypedefNameDecl *Typedef = cast<TypedefType>(T)->getDecl();
1051    std::pair<uint64_t, unsigned> Info
1052      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
1053    // If the typedef has an aligned attribute on it, it overrides any computed
1054    // alignment we have.  This violates the GCC documentation (which says that
1055    // attribute(aligned) can only round up) but matches its implementation.
1056    if (unsigned AttrAlign = Typedef->getMaxAlignment())
1057      Align = AttrAlign;
1058    else
1059      Align = Info.second;
1060    Width = Info.first;
1061    break;
1062  }
1063
1064  case Type::TypeOfExpr:
1065    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
1066                         .getTypePtr());
1067
1068  case Type::TypeOf:
1069    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
1070
1071  case Type::Decltype:
1072    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
1073                        .getTypePtr());
1074
1075  case Type::UnaryTransform:
1076    return getTypeInfo(cast<UnaryTransformType>(T)->getUnderlyingType());
1077
1078  case Type::Elaborated:
1079    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
1080
1081  case Type::Attributed:
1082    return getTypeInfo(
1083                  cast<AttributedType>(T)->getEquivalentType().getTypePtr());
1084
1085  case Type::TemplateSpecialization: {
1086    assert(getCanonicalType(T) != T &&
1087           "Cannot request the size of a dependent type");
1088    const TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T);
1089    // A type alias template specialization may refer to a typedef with the
1090    // aligned attribute on it.
1091    if (TST->isTypeAlias())
1092      return getTypeInfo(TST->getAliasedType().getTypePtr());
1093    else
1094      return getTypeInfo(getCanonicalType(T));
1095  }
1096
1097  case Type::Atomic: {
1098    std::pair<uint64_t, unsigned> Info
1099      = getTypeInfo(cast<AtomicType>(T)->getValueType());
1100    Width = Info.first;
1101    Align = Info.second;
1102    if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth() &&
1103        llvm::isPowerOf2_64(Width)) {
1104      // We can potentially perform lock-free atomic operations for this
1105      // type; promote the alignment appropriately.
1106      // FIXME: We could potentially promote the width here as well...
1107      // is that worthwhile?  (Non-struct atomic types generally have
1108      // power-of-two size anyway, but structs might not.  Requires a bit
1109      // of implementation work to make sure we zero out the extra bits.)
1110      Align = static_cast<unsigned>(Width);
1111    }
1112  }
1113
1114  }
1115
1116  assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
1117  return std::make_pair(Width, Align);
1118}
1119
1120/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1121CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1122  return CharUnits::fromQuantity(BitSize / getCharWidth());
1123}
1124
1125/// toBits - Convert a size in characters to a size in characters.
1126int64_t ASTContext::toBits(CharUnits CharSize) const {
1127  return CharSize.getQuantity() * getCharWidth();
1128}
1129
1130/// getTypeSizeInChars - Return the size of the specified type, in characters.
1131/// This method does not work on incomplete types.
1132CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1133  return toCharUnitsFromBits(getTypeSize(T));
1134}
1135CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1136  return toCharUnitsFromBits(getTypeSize(T));
1137}
1138
1139/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1140/// characters. This method does not work on incomplete types.
1141CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1142  return toCharUnitsFromBits(getTypeAlign(T));
1143}
1144CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1145  return toCharUnitsFromBits(getTypeAlign(T));
1146}
1147
1148/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1149/// type for the current target in bits.  This can be different than the ABI
1150/// alignment in cases where it is beneficial for performance to overalign
1151/// a data type.
1152unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1153  unsigned ABIAlign = getTypeAlign(T);
1154
1155  // Double and long long should be naturally aligned if possible.
1156  if (const ComplexType* CT = T->getAs<ComplexType>())
1157    T = CT->getElementType().getTypePtr();
1158  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1159      T->isSpecificBuiltinType(BuiltinType::LongLong))
1160    return std::max(ABIAlign, (unsigned)getTypeSize(T));
1161
1162  return ABIAlign;
1163}
1164
1165/// DeepCollectObjCIvars -
1166/// This routine first collects all declared, but not synthesized, ivars in
1167/// super class and then collects all ivars, including those synthesized for
1168/// current class. This routine is used for implementation of current class
1169/// when all ivars, declared and synthesized are known.
1170///
1171void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1172                                      bool leafClass,
1173                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1174  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1175    DeepCollectObjCIvars(SuperClass, false, Ivars);
1176  if (!leafClass) {
1177    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
1178         E = OI->ivar_end(); I != E; ++I)
1179      Ivars.push_back(*I);
1180  } else {
1181    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1182    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1183         Iv= Iv->getNextIvar())
1184      Ivars.push_back(Iv);
1185  }
1186}
1187
1188/// CollectInheritedProtocols - Collect all protocols in current class and
1189/// those inherited by it.
1190void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1191                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1192  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1193    // We can use protocol_iterator here instead of
1194    // all_referenced_protocol_iterator since we are walking all categories.
1195    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
1196         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
1197      ObjCProtocolDecl *Proto = (*P);
1198      Protocols.insert(Proto->getCanonicalDecl());
1199      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1200           PE = Proto->protocol_end(); P != PE; ++P) {
1201        Protocols.insert((*P)->getCanonicalDecl());
1202        CollectInheritedProtocols(*P, Protocols);
1203      }
1204    }
1205
1206    // Categories of this Interface.
1207    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
1208         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
1209      CollectInheritedProtocols(CDeclChain, Protocols);
1210    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1211      while (SD) {
1212        CollectInheritedProtocols(SD, Protocols);
1213        SD = SD->getSuperClass();
1214      }
1215  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1216    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
1217         PE = OC->protocol_end(); P != PE; ++P) {
1218      ObjCProtocolDecl *Proto = (*P);
1219      Protocols.insert(Proto->getCanonicalDecl());
1220      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1221           PE = Proto->protocol_end(); P != PE; ++P)
1222        CollectInheritedProtocols(*P, Protocols);
1223    }
1224  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
1225    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
1226         PE = OP->protocol_end(); P != PE; ++P) {
1227      ObjCProtocolDecl *Proto = (*P);
1228      Protocols.insert(Proto->getCanonicalDecl());
1229      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1230           PE = Proto->protocol_end(); P != PE; ++P)
1231        CollectInheritedProtocols(*P, Protocols);
1232    }
1233  }
1234}
1235
1236unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
1237  unsigned count = 0;
1238  // Count ivars declared in class extension.
1239  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
1240       CDecl = CDecl->getNextClassExtension())
1241    count += CDecl->ivar_size();
1242
1243  // Count ivar defined in this class's implementation.  This
1244  // includes synthesized ivars.
1245  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
1246    count += ImplDecl->ivar_size();
1247
1248  return count;
1249}
1250
1251/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
1252ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
1253  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1254    I = ObjCImpls.find(D);
1255  if (I != ObjCImpls.end())
1256    return cast<ObjCImplementationDecl>(I->second);
1257  return 0;
1258}
1259/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
1260ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
1261  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1262    I = ObjCImpls.find(D);
1263  if (I != ObjCImpls.end())
1264    return cast<ObjCCategoryImplDecl>(I->second);
1265  return 0;
1266}
1267
1268/// \brief Set the implementation of ObjCInterfaceDecl.
1269void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1270                           ObjCImplementationDecl *ImplD) {
1271  assert(IFaceD && ImplD && "Passed null params");
1272  ObjCImpls[IFaceD] = ImplD;
1273}
1274/// \brief Set the implementation of ObjCCategoryDecl.
1275void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1276                           ObjCCategoryImplDecl *ImplD) {
1277  assert(CatD && ImplD && "Passed null params");
1278  ObjCImpls[CatD] = ImplD;
1279}
1280
1281ObjCInterfaceDecl *ASTContext::getObjContainingInterface(NamedDecl *ND) const {
1282  if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(ND->getDeclContext()))
1283    return ID;
1284  if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(ND->getDeclContext()))
1285    return CD->getClassInterface();
1286  if (ObjCImplDecl *IMD = dyn_cast<ObjCImplDecl>(ND->getDeclContext()))
1287    return IMD->getClassInterface();
1288
1289  return 0;
1290}
1291
1292/// \brief Get the copy initialization expression of VarDecl,or NULL if
1293/// none exists.
1294Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
1295  assert(VD && "Passed null params");
1296  assert(VD->hasAttr<BlocksAttr>() &&
1297         "getBlockVarCopyInits - not __block var");
1298  llvm::DenseMap<const VarDecl*, Expr*>::iterator
1299    I = BlockVarCopyInits.find(VD);
1300  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : 0;
1301}
1302
1303/// \brief Set the copy inialization expression of a block var decl.
1304void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
1305  assert(VD && Init && "Passed null params");
1306  assert(VD->hasAttr<BlocksAttr>() &&
1307         "setBlockVarCopyInits - not __block var");
1308  BlockVarCopyInits[VD] = Init;
1309}
1310
1311/// \brief Allocate an uninitialized TypeSourceInfo.
1312///
1313/// The caller should initialize the memory held by TypeSourceInfo using
1314/// the TypeLoc wrappers.
1315///
1316/// \param T the type that will be the basis for type source info. This type
1317/// should refer to how the declarator was written in source code, not to
1318/// what type semantic analysis resolved the declarator to.
1319TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1320                                                 unsigned DataSize) const {
1321  if (!DataSize)
1322    DataSize = TypeLoc::getFullDataSizeForType(T);
1323  else
1324    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1325           "incorrect data size provided to CreateTypeSourceInfo!");
1326
1327  TypeSourceInfo *TInfo =
1328    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1329  new (TInfo) TypeSourceInfo(T);
1330  return TInfo;
1331}
1332
1333TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1334                                                     SourceLocation L) const {
1335  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1336  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
1337  return DI;
1338}
1339
1340const ASTRecordLayout &
1341ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
1342  return getObjCLayout(D, 0);
1343}
1344
1345const ASTRecordLayout &
1346ASTContext::getASTObjCImplementationLayout(
1347                                        const ObjCImplementationDecl *D) const {
1348  return getObjCLayout(D->getClassInterface(), D);
1349}
1350
1351//===----------------------------------------------------------------------===//
1352//                   Type creation/memoization methods
1353//===----------------------------------------------------------------------===//
1354
1355QualType
1356ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
1357  unsigned fastQuals = quals.getFastQualifiers();
1358  quals.removeFastQualifiers();
1359
1360  // Check if we've already instantiated this type.
1361  llvm::FoldingSetNodeID ID;
1362  ExtQuals::Profile(ID, baseType, quals);
1363  void *insertPos = 0;
1364  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
1365    assert(eq->getQualifiers() == quals);
1366    return QualType(eq, fastQuals);
1367  }
1368
1369  // If the base type is not canonical, make the appropriate canonical type.
1370  QualType canon;
1371  if (!baseType->isCanonicalUnqualified()) {
1372    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
1373    canonSplit.second.addConsistentQualifiers(quals);
1374    canon = getExtQualType(canonSplit.first, canonSplit.second);
1375
1376    // Re-find the insert position.
1377    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
1378  }
1379
1380  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
1381  ExtQualNodes.InsertNode(eq, insertPos);
1382  return QualType(eq, fastQuals);
1383}
1384
1385QualType
1386ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
1387  QualType CanT = getCanonicalType(T);
1388  if (CanT.getAddressSpace() == AddressSpace)
1389    return T;
1390
1391  // If we are composing extended qualifiers together, merge together
1392  // into one ExtQuals node.
1393  QualifierCollector Quals;
1394  const Type *TypeNode = Quals.strip(T);
1395
1396  // If this type already has an address space specified, it cannot get
1397  // another one.
1398  assert(!Quals.hasAddressSpace() &&
1399         "Type cannot be in multiple addr spaces!");
1400  Quals.addAddressSpace(AddressSpace);
1401
1402  return getExtQualType(TypeNode, Quals);
1403}
1404
1405QualType ASTContext::getObjCGCQualType(QualType T,
1406                                       Qualifiers::GC GCAttr) const {
1407  QualType CanT = getCanonicalType(T);
1408  if (CanT.getObjCGCAttr() == GCAttr)
1409    return T;
1410
1411  if (const PointerType *ptr = T->getAs<PointerType>()) {
1412    QualType Pointee = ptr->getPointeeType();
1413    if (Pointee->isAnyPointerType()) {
1414      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1415      return getPointerType(ResultType);
1416    }
1417  }
1418
1419  // If we are composing extended qualifiers together, merge together
1420  // into one ExtQuals node.
1421  QualifierCollector Quals;
1422  const Type *TypeNode = Quals.strip(T);
1423
1424  // If this type already has an ObjCGC specified, it cannot get
1425  // another one.
1426  assert(!Quals.hasObjCGCAttr() &&
1427         "Type cannot have multiple ObjCGCs!");
1428  Quals.addObjCGCAttr(GCAttr);
1429
1430  return getExtQualType(TypeNode, Quals);
1431}
1432
1433const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
1434                                                   FunctionType::ExtInfo Info) {
1435  if (T->getExtInfo() == Info)
1436    return T;
1437
1438  QualType Result;
1439  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
1440    Result = getFunctionNoProtoType(FNPT->getResultType(), Info);
1441  } else {
1442    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
1443    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
1444    EPI.ExtInfo = Info;
1445    Result = getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1446                             FPT->getNumArgs(), EPI);
1447  }
1448
1449  return cast<FunctionType>(Result.getTypePtr());
1450}
1451
1452/// getComplexType - Return the uniqued reference to the type for a complex
1453/// number with the specified element type.
1454QualType ASTContext::getComplexType(QualType T) const {
1455  // Unique pointers, to guarantee there is only one pointer of a particular
1456  // structure.
1457  llvm::FoldingSetNodeID ID;
1458  ComplexType::Profile(ID, T);
1459
1460  void *InsertPos = 0;
1461  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1462    return QualType(CT, 0);
1463
1464  // If the pointee type isn't canonical, this won't be a canonical type either,
1465  // so fill in the canonical type field.
1466  QualType Canonical;
1467  if (!T.isCanonical()) {
1468    Canonical = getComplexType(getCanonicalType(T));
1469
1470    // Get the new insert position for the node we care about.
1471    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1472    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1473  }
1474  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1475  Types.push_back(New);
1476  ComplexTypes.InsertNode(New, InsertPos);
1477  return QualType(New, 0);
1478}
1479
1480/// getPointerType - Return the uniqued reference to the type for a pointer to
1481/// the specified type.
1482QualType ASTContext::getPointerType(QualType T) const {
1483  // Unique pointers, to guarantee there is only one pointer of a particular
1484  // structure.
1485  llvm::FoldingSetNodeID ID;
1486  PointerType::Profile(ID, T);
1487
1488  void *InsertPos = 0;
1489  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1490    return QualType(PT, 0);
1491
1492  // If the pointee type isn't canonical, this won't be a canonical type either,
1493  // so fill in the canonical type field.
1494  QualType Canonical;
1495  if (!T.isCanonical()) {
1496    Canonical = getPointerType(getCanonicalType(T));
1497
1498    // Get the new insert position for the node we care about.
1499    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1500    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1501  }
1502  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1503  Types.push_back(New);
1504  PointerTypes.InsertNode(New, InsertPos);
1505  return QualType(New, 0);
1506}
1507
1508/// getBlockPointerType - Return the uniqued reference to the type for
1509/// a pointer to the specified block.
1510QualType ASTContext::getBlockPointerType(QualType T) const {
1511  assert(T->isFunctionType() && "block of function types only");
1512  // Unique pointers, to guarantee there is only one block of a particular
1513  // structure.
1514  llvm::FoldingSetNodeID ID;
1515  BlockPointerType::Profile(ID, T);
1516
1517  void *InsertPos = 0;
1518  if (BlockPointerType *PT =
1519        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1520    return QualType(PT, 0);
1521
1522  // If the block pointee type isn't canonical, this won't be a canonical
1523  // type either so fill in the canonical type field.
1524  QualType Canonical;
1525  if (!T.isCanonical()) {
1526    Canonical = getBlockPointerType(getCanonicalType(T));
1527
1528    // Get the new insert position for the node we care about.
1529    BlockPointerType *NewIP =
1530      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1531    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1532  }
1533  BlockPointerType *New
1534    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1535  Types.push_back(New);
1536  BlockPointerTypes.InsertNode(New, InsertPos);
1537  return QualType(New, 0);
1538}
1539
1540/// getLValueReferenceType - Return the uniqued reference to the type for an
1541/// lvalue reference to the specified type.
1542QualType
1543ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
1544  assert(getCanonicalType(T) != OverloadTy &&
1545         "Unresolved overloaded function type");
1546
1547  // Unique pointers, to guarantee there is only one pointer of a particular
1548  // structure.
1549  llvm::FoldingSetNodeID ID;
1550  ReferenceType::Profile(ID, T, SpelledAsLValue);
1551
1552  void *InsertPos = 0;
1553  if (LValueReferenceType *RT =
1554        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1555    return QualType(RT, 0);
1556
1557  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1558
1559  // If the referencee type isn't canonical, this won't be a canonical type
1560  // either, so fill in the canonical type field.
1561  QualType Canonical;
1562  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1563    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1564    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1565
1566    // Get the new insert position for the node we care about.
1567    LValueReferenceType *NewIP =
1568      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1569    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1570  }
1571
1572  LValueReferenceType *New
1573    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1574                                                     SpelledAsLValue);
1575  Types.push_back(New);
1576  LValueReferenceTypes.InsertNode(New, InsertPos);
1577
1578  return QualType(New, 0);
1579}
1580
1581/// getRValueReferenceType - Return the uniqued reference to the type for an
1582/// rvalue reference to the specified type.
1583QualType ASTContext::getRValueReferenceType(QualType T) const {
1584  // Unique pointers, to guarantee there is only one pointer of a particular
1585  // structure.
1586  llvm::FoldingSetNodeID ID;
1587  ReferenceType::Profile(ID, T, false);
1588
1589  void *InsertPos = 0;
1590  if (RValueReferenceType *RT =
1591        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1592    return QualType(RT, 0);
1593
1594  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1595
1596  // If the referencee type isn't canonical, this won't be a canonical type
1597  // either, so fill in the canonical type field.
1598  QualType Canonical;
1599  if (InnerRef || !T.isCanonical()) {
1600    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1601    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1602
1603    // Get the new insert position for the node we care about.
1604    RValueReferenceType *NewIP =
1605      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1606    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1607  }
1608
1609  RValueReferenceType *New
1610    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1611  Types.push_back(New);
1612  RValueReferenceTypes.InsertNode(New, InsertPos);
1613  return QualType(New, 0);
1614}
1615
1616/// getMemberPointerType - Return the uniqued reference to the type for a
1617/// member pointer to the specified type, in the specified class.
1618QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
1619  // Unique pointers, to guarantee there is only one pointer of a particular
1620  // structure.
1621  llvm::FoldingSetNodeID ID;
1622  MemberPointerType::Profile(ID, T, Cls);
1623
1624  void *InsertPos = 0;
1625  if (MemberPointerType *PT =
1626      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1627    return QualType(PT, 0);
1628
1629  // If the pointee or class type isn't canonical, this won't be a canonical
1630  // type either, so fill in the canonical type field.
1631  QualType Canonical;
1632  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1633    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1634
1635    // Get the new insert position for the node we care about.
1636    MemberPointerType *NewIP =
1637      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1638    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1639  }
1640  MemberPointerType *New
1641    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1642  Types.push_back(New);
1643  MemberPointerTypes.InsertNode(New, InsertPos);
1644  return QualType(New, 0);
1645}
1646
1647/// getConstantArrayType - Return the unique reference to the type for an
1648/// array of the specified element type.
1649QualType ASTContext::getConstantArrayType(QualType EltTy,
1650                                          const llvm::APInt &ArySizeIn,
1651                                          ArrayType::ArraySizeModifier ASM,
1652                                          unsigned IndexTypeQuals) const {
1653  assert((EltTy->isDependentType() ||
1654          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1655         "Constant array of VLAs is illegal!");
1656
1657  // Convert the array size into a canonical width matching the pointer size for
1658  // the target.
1659  llvm::APInt ArySize(ArySizeIn);
1660  ArySize =
1661    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
1662
1663  llvm::FoldingSetNodeID ID;
1664  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
1665
1666  void *InsertPos = 0;
1667  if (ConstantArrayType *ATP =
1668      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1669    return QualType(ATP, 0);
1670
1671  // If the element type isn't canonical or has qualifiers, this won't
1672  // be a canonical type either, so fill in the canonical type field.
1673  QualType Canon;
1674  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1675    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1676    Canon = getConstantArrayType(QualType(canonSplit.first, 0), ArySize,
1677                                 ASM, IndexTypeQuals);
1678    Canon = getQualifiedType(Canon, canonSplit.second);
1679
1680    // Get the new insert position for the node we care about.
1681    ConstantArrayType *NewIP =
1682      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1683    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1684  }
1685
1686  ConstantArrayType *New = new(*this,TypeAlignment)
1687    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
1688  ConstantArrayTypes.InsertNode(New, InsertPos);
1689  Types.push_back(New);
1690  return QualType(New, 0);
1691}
1692
1693/// getVariableArrayDecayedType - Turns the given type, which may be
1694/// variably-modified, into the corresponding type with all the known
1695/// sizes replaced with [*].
1696QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
1697  // Vastly most common case.
1698  if (!type->isVariablyModifiedType()) return type;
1699
1700  QualType result;
1701
1702  SplitQualType split = type.getSplitDesugaredType();
1703  const Type *ty = split.first;
1704  switch (ty->getTypeClass()) {
1705#define TYPE(Class, Base)
1706#define ABSTRACT_TYPE(Class, Base)
1707#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
1708#include "clang/AST/TypeNodes.def"
1709    llvm_unreachable("didn't desugar past all non-canonical types?");
1710
1711  // These types should never be variably-modified.
1712  case Type::Builtin:
1713  case Type::Complex:
1714  case Type::Vector:
1715  case Type::ExtVector:
1716  case Type::DependentSizedExtVector:
1717  case Type::ObjCObject:
1718  case Type::ObjCInterface:
1719  case Type::ObjCObjectPointer:
1720  case Type::Record:
1721  case Type::Enum:
1722  case Type::UnresolvedUsing:
1723  case Type::TypeOfExpr:
1724  case Type::TypeOf:
1725  case Type::Decltype:
1726  case Type::UnaryTransform:
1727  case Type::DependentName:
1728  case Type::InjectedClassName:
1729  case Type::TemplateSpecialization:
1730  case Type::DependentTemplateSpecialization:
1731  case Type::TemplateTypeParm:
1732  case Type::SubstTemplateTypeParmPack:
1733  case Type::Auto:
1734  case Type::PackExpansion:
1735    llvm_unreachable("type should never be variably-modified");
1736
1737  // These types can be variably-modified but should never need to
1738  // further decay.
1739  case Type::FunctionNoProto:
1740  case Type::FunctionProto:
1741  case Type::BlockPointer:
1742  case Type::MemberPointer:
1743    return type;
1744
1745  // These types can be variably-modified.  All these modifications
1746  // preserve structure except as noted by comments.
1747  // TODO: if we ever care about optimizing VLAs, there are no-op
1748  // optimizations available here.
1749  case Type::Pointer:
1750    result = getPointerType(getVariableArrayDecayedType(
1751                              cast<PointerType>(ty)->getPointeeType()));
1752    break;
1753
1754  case Type::LValueReference: {
1755    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
1756    result = getLValueReferenceType(
1757                 getVariableArrayDecayedType(lv->getPointeeType()),
1758                                    lv->isSpelledAsLValue());
1759    break;
1760  }
1761
1762  case Type::RValueReference: {
1763    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
1764    result = getRValueReferenceType(
1765                 getVariableArrayDecayedType(lv->getPointeeType()));
1766    break;
1767  }
1768
1769  case Type::Atomic: {
1770    const AtomicType *at = cast<AtomicType>(ty);
1771    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
1772    break;
1773  }
1774
1775  case Type::ConstantArray: {
1776    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
1777    result = getConstantArrayType(
1778                 getVariableArrayDecayedType(cat->getElementType()),
1779                                  cat->getSize(),
1780                                  cat->getSizeModifier(),
1781                                  cat->getIndexTypeCVRQualifiers());
1782    break;
1783  }
1784
1785  case Type::DependentSizedArray: {
1786    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
1787    result = getDependentSizedArrayType(
1788                 getVariableArrayDecayedType(dat->getElementType()),
1789                                        dat->getSizeExpr(),
1790                                        dat->getSizeModifier(),
1791                                        dat->getIndexTypeCVRQualifiers(),
1792                                        dat->getBracketsRange());
1793    break;
1794  }
1795
1796  // Turn incomplete types into [*] types.
1797  case Type::IncompleteArray: {
1798    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
1799    result = getVariableArrayType(
1800                 getVariableArrayDecayedType(iat->getElementType()),
1801                                  /*size*/ 0,
1802                                  ArrayType::Normal,
1803                                  iat->getIndexTypeCVRQualifiers(),
1804                                  SourceRange());
1805    break;
1806  }
1807
1808  // Turn VLA types into [*] types.
1809  case Type::VariableArray: {
1810    const VariableArrayType *vat = cast<VariableArrayType>(ty);
1811    result = getVariableArrayType(
1812                 getVariableArrayDecayedType(vat->getElementType()),
1813                                  /*size*/ 0,
1814                                  ArrayType::Star,
1815                                  vat->getIndexTypeCVRQualifiers(),
1816                                  vat->getBracketsRange());
1817    break;
1818  }
1819  }
1820
1821  // Apply the top-level qualifiers from the original.
1822  return getQualifiedType(result, split.second);
1823}
1824
1825/// getVariableArrayType - Returns a non-unique reference to the type for a
1826/// variable array of the specified element type.
1827QualType ASTContext::getVariableArrayType(QualType EltTy,
1828                                          Expr *NumElts,
1829                                          ArrayType::ArraySizeModifier ASM,
1830                                          unsigned IndexTypeQuals,
1831                                          SourceRange Brackets) const {
1832  // Since we don't unique expressions, it isn't possible to unique VLA's
1833  // that have an expression provided for their size.
1834  QualType Canon;
1835
1836  // Be sure to pull qualifiers off the element type.
1837  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1838    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1839    Canon = getVariableArrayType(QualType(canonSplit.first, 0), NumElts, ASM,
1840                                 IndexTypeQuals, Brackets);
1841    Canon = getQualifiedType(Canon, canonSplit.second);
1842  }
1843
1844  VariableArrayType *New = new(*this, TypeAlignment)
1845    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
1846
1847  VariableArrayTypes.push_back(New);
1848  Types.push_back(New);
1849  return QualType(New, 0);
1850}
1851
1852/// getDependentSizedArrayType - Returns a non-unique reference to
1853/// the type for a dependently-sized array of the specified element
1854/// type.
1855QualType ASTContext::getDependentSizedArrayType(QualType elementType,
1856                                                Expr *numElements,
1857                                                ArrayType::ArraySizeModifier ASM,
1858                                                unsigned elementTypeQuals,
1859                                                SourceRange brackets) const {
1860  assert((!numElements || numElements->isTypeDependent() ||
1861          numElements->isValueDependent()) &&
1862         "Size must be type- or value-dependent!");
1863
1864  // Dependently-sized array types that do not have a specified number
1865  // of elements will have their sizes deduced from a dependent
1866  // initializer.  We do no canonicalization here at all, which is okay
1867  // because they can't be used in most locations.
1868  if (!numElements) {
1869    DependentSizedArrayType *newType
1870      = new (*this, TypeAlignment)
1871          DependentSizedArrayType(*this, elementType, QualType(),
1872                                  numElements, ASM, elementTypeQuals,
1873                                  brackets);
1874    Types.push_back(newType);
1875    return QualType(newType, 0);
1876  }
1877
1878  // Otherwise, we actually build a new type every time, but we
1879  // also build a canonical type.
1880
1881  SplitQualType canonElementType = getCanonicalType(elementType).split();
1882
1883  void *insertPos = 0;
1884  llvm::FoldingSetNodeID ID;
1885  DependentSizedArrayType::Profile(ID, *this,
1886                                   QualType(canonElementType.first, 0),
1887                                   ASM, elementTypeQuals, numElements);
1888
1889  // Look for an existing type with these properties.
1890  DependentSizedArrayType *canonTy =
1891    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1892
1893  // If we don't have one, build one.
1894  if (!canonTy) {
1895    canonTy = new (*this, TypeAlignment)
1896      DependentSizedArrayType(*this, QualType(canonElementType.first, 0),
1897                              QualType(), numElements, ASM, elementTypeQuals,
1898                              brackets);
1899    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
1900    Types.push_back(canonTy);
1901  }
1902
1903  // Apply qualifiers from the element type to the array.
1904  QualType canon = getQualifiedType(QualType(canonTy,0),
1905                                    canonElementType.second);
1906
1907  // If we didn't need extra canonicalization for the element type,
1908  // then just use that as our result.
1909  if (QualType(canonElementType.first, 0) == elementType)
1910    return canon;
1911
1912  // Otherwise, we need to build a type which follows the spelling
1913  // of the element type.
1914  DependentSizedArrayType *sugaredType
1915    = new (*this, TypeAlignment)
1916        DependentSizedArrayType(*this, elementType, canon, numElements,
1917                                ASM, elementTypeQuals, brackets);
1918  Types.push_back(sugaredType);
1919  return QualType(sugaredType, 0);
1920}
1921
1922QualType ASTContext::getIncompleteArrayType(QualType elementType,
1923                                            ArrayType::ArraySizeModifier ASM,
1924                                            unsigned elementTypeQuals) const {
1925  llvm::FoldingSetNodeID ID;
1926  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
1927
1928  void *insertPos = 0;
1929  if (IncompleteArrayType *iat =
1930       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
1931    return QualType(iat, 0);
1932
1933  // If the element type isn't canonical, this won't be a canonical type
1934  // either, so fill in the canonical type field.  We also have to pull
1935  // qualifiers off the element type.
1936  QualType canon;
1937
1938  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
1939    SplitQualType canonSplit = getCanonicalType(elementType).split();
1940    canon = getIncompleteArrayType(QualType(canonSplit.first, 0),
1941                                   ASM, elementTypeQuals);
1942    canon = getQualifiedType(canon, canonSplit.second);
1943
1944    // Get the new insert position for the node we care about.
1945    IncompleteArrayType *existing =
1946      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1947    assert(!existing && "Shouldn't be in the map!"); (void) existing;
1948  }
1949
1950  IncompleteArrayType *newType = new (*this, TypeAlignment)
1951    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
1952
1953  IncompleteArrayTypes.InsertNode(newType, insertPos);
1954  Types.push_back(newType);
1955  return QualType(newType, 0);
1956}
1957
1958/// getVectorType - Return the unique reference to a vector type of
1959/// the specified element type and size. VectorType must be a built-in type.
1960QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1961                                   VectorType::VectorKind VecKind) const {
1962  assert(vecType->isBuiltinType());
1963
1964  // Check if we've already instantiated a vector of this type.
1965  llvm::FoldingSetNodeID ID;
1966  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
1967
1968  void *InsertPos = 0;
1969  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1970    return QualType(VTP, 0);
1971
1972  // If the element type isn't canonical, this won't be a canonical type either,
1973  // so fill in the canonical type field.
1974  QualType Canonical;
1975  if (!vecType.isCanonical()) {
1976    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
1977
1978    // Get the new insert position for the node we care about.
1979    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1980    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1981  }
1982  VectorType *New = new (*this, TypeAlignment)
1983    VectorType(vecType, NumElts, Canonical, VecKind);
1984  VectorTypes.InsertNode(New, InsertPos);
1985  Types.push_back(New);
1986  return QualType(New, 0);
1987}
1988
1989/// getExtVectorType - Return the unique reference to an extended vector type of
1990/// the specified element type and size. VectorType must be a built-in type.
1991QualType
1992ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
1993  assert(vecType->isBuiltinType() || vecType->isDependentType());
1994
1995  // Check if we've already instantiated a vector of this type.
1996  llvm::FoldingSetNodeID ID;
1997  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1998                      VectorType::GenericVector);
1999  void *InsertPos = 0;
2000  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2001    return QualType(VTP, 0);
2002
2003  // If the element type isn't canonical, this won't be a canonical type either,
2004  // so fill in the canonical type field.
2005  QualType Canonical;
2006  if (!vecType.isCanonical()) {
2007    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
2008
2009    // Get the new insert position for the node we care about.
2010    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2011    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2012  }
2013  ExtVectorType *New = new (*this, TypeAlignment)
2014    ExtVectorType(vecType, NumElts, Canonical);
2015  VectorTypes.InsertNode(New, InsertPos);
2016  Types.push_back(New);
2017  return QualType(New, 0);
2018}
2019
2020QualType
2021ASTContext::getDependentSizedExtVectorType(QualType vecType,
2022                                           Expr *SizeExpr,
2023                                           SourceLocation AttrLoc) const {
2024  llvm::FoldingSetNodeID ID;
2025  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
2026                                       SizeExpr);
2027
2028  void *InsertPos = 0;
2029  DependentSizedExtVectorType *Canon
2030    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2031  DependentSizedExtVectorType *New;
2032  if (Canon) {
2033    // We already have a canonical version of this array type; use it as
2034    // the canonical type for a newly-built type.
2035    New = new (*this, TypeAlignment)
2036      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
2037                                  SizeExpr, AttrLoc);
2038  } else {
2039    QualType CanonVecTy = getCanonicalType(vecType);
2040    if (CanonVecTy == vecType) {
2041      New = new (*this, TypeAlignment)
2042        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
2043                                    AttrLoc);
2044
2045      DependentSizedExtVectorType *CanonCheck
2046        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2047      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
2048      (void)CanonCheck;
2049      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
2050    } else {
2051      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
2052                                                      SourceLocation());
2053      New = new (*this, TypeAlignment)
2054        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2055    }
2056  }
2057
2058  Types.push_back(New);
2059  return QualType(New, 0);
2060}
2061
2062/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
2063///
2064QualType
2065ASTContext::getFunctionNoProtoType(QualType ResultTy,
2066                                   const FunctionType::ExtInfo &Info) const {
2067  const CallingConv DefaultCC = Info.getCC();
2068  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2069                               CC_X86StdCall : DefaultCC;
2070  // Unique functions, to guarantee there is only one function of a particular
2071  // structure.
2072  llvm::FoldingSetNodeID ID;
2073  FunctionNoProtoType::Profile(ID, ResultTy, Info);
2074
2075  void *InsertPos = 0;
2076  if (FunctionNoProtoType *FT =
2077        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2078    return QualType(FT, 0);
2079
2080  QualType Canonical;
2081  if (!ResultTy.isCanonical() ||
2082      getCanonicalCallConv(CallConv) != CallConv) {
2083    Canonical =
2084      getFunctionNoProtoType(getCanonicalType(ResultTy),
2085                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
2086
2087    // Get the new insert position for the node we care about.
2088    FunctionNoProtoType *NewIP =
2089      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2090    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2091  }
2092
2093  FunctionProtoType::ExtInfo newInfo = Info.withCallingConv(CallConv);
2094  FunctionNoProtoType *New = new (*this, TypeAlignment)
2095    FunctionNoProtoType(ResultTy, Canonical, newInfo);
2096  Types.push_back(New);
2097  FunctionNoProtoTypes.InsertNode(New, InsertPos);
2098  return QualType(New, 0);
2099}
2100
2101/// getFunctionType - Return a normal function type with a typed argument
2102/// list.  isVariadic indicates whether the argument list includes '...'.
2103QualType
2104ASTContext::getFunctionType(QualType ResultTy,
2105                            const QualType *ArgArray, unsigned NumArgs,
2106                            const FunctionProtoType::ExtProtoInfo &EPI) const {
2107  // Unique functions, to guarantee there is only one function of a particular
2108  // structure.
2109  llvm::FoldingSetNodeID ID;
2110  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, EPI, *this);
2111
2112  void *InsertPos = 0;
2113  if (FunctionProtoType *FTP =
2114        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2115    return QualType(FTP, 0);
2116
2117  // Determine whether the type being created is already canonical or not.
2118  bool isCanonical= EPI.ExceptionSpecType == EST_None && ResultTy.isCanonical();
2119  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
2120    if (!ArgArray[i].isCanonicalAsParam())
2121      isCanonical = false;
2122
2123  const CallingConv DefaultCC = EPI.ExtInfo.getCC();
2124  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2125                               CC_X86StdCall : DefaultCC;
2126
2127  // If this type isn't canonical, get the canonical version of it.
2128  // The exception spec is not part of the canonical type.
2129  QualType Canonical;
2130  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
2131    SmallVector<QualType, 16> CanonicalArgs;
2132    CanonicalArgs.reserve(NumArgs);
2133    for (unsigned i = 0; i != NumArgs; ++i)
2134      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
2135
2136    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
2137    CanonicalEPI.ExceptionSpecType = EST_None;
2138    CanonicalEPI.NumExceptions = 0;
2139    CanonicalEPI.ExtInfo
2140      = CanonicalEPI.ExtInfo.withCallingConv(getCanonicalCallConv(CallConv));
2141
2142    Canonical = getFunctionType(getCanonicalType(ResultTy),
2143                                CanonicalArgs.data(), NumArgs,
2144                                CanonicalEPI);
2145
2146    // Get the new insert position for the node we care about.
2147    FunctionProtoType *NewIP =
2148      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2149    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2150  }
2151
2152  // FunctionProtoType objects are allocated with extra bytes after
2153  // them for three variable size arrays at the end:
2154  //  - parameter types
2155  //  - exception types
2156  //  - consumed-arguments flags
2157  // Instead of the exception types, there could be a noexcept
2158  // expression.
2159  size_t Size = sizeof(FunctionProtoType) +
2160                NumArgs * sizeof(QualType);
2161  if (EPI.ExceptionSpecType == EST_Dynamic)
2162    Size += EPI.NumExceptions * sizeof(QualType);
2163  else if (EPI.ExceptionSpecType == EST_ComputedNoexcept) {
2164    Size += sizeof(Expr*);
2165  }
2166  if (EPI.ConsumedArguments)
2167    Size += NumArgs * sizeof(bool);
2168
2169  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
2170  FunctionProtoType::ExtProtoInfo newEPI = EPI;
2171  newEPI.ExtInfo = EPI.ExtInfo.withCallingConv(CallConv);
2172  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, Canonical, newEPI);
2173  Types.push_back(FTP);
2174  FunctionProtoTypes.InsertNode(FTP, InsertPos);
2175  return QualType(FTP, 0);
2176}
2177
2178#ifndef NDEBUG
2179static bool NeedsInjectedClassNameType(const RecordDecl *D) {
2180  if (!isa<CXXRecordDecl>(D)) return false;
2181  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
2182  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
2183    return true;
2184  if (RD->getDescribedClassTemplate() &&
2185      !isa<ClassTemplateSpecializationDecl>(RD))
2186    return true;
2187  return false;
2188}
2189#endif
2190
2191/// getInjectedClassNameType - Return the unique reference to the
2192/// injected class name type for the specified templated declaration.
2193QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
2194                                              QualType TST) const {
2195  assert(NeedsInjectedClassNameType(Decl));
2196  if (Decl->TypeForDecl) {
2197    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2198  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDecl()) {
2199    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
2200    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2201    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2202  } else {
2203    Type *newType =
2204      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
2205    Decl->TypeForDecl = newType;
2206    Types.push_back(newType);
2207  }
2208  return QualType(Decl->TypeForDecl, 0);
2209}
2210
2211/// getTypeDeclType - Return the unique reference to the type for the
2212/// specified type declaration.
2213QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) const {
2214  assert(Decl && "Passed null for Decl param");
2215  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
2216
2217  if (const TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Decl))
2218    return getTypedefType(Typedef);
2219
2220  assert(!isa<TemplateTypeParmDecl>(Decl) &&
2221         "Template type parameter types are always available.");
2222
2223  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
2224    assert(!Record->getPreviousDecl() &&
2225           "struct/union has previous declaration");
2226    assert(!NeedsInjectedClassNameType(Record));
2227    return getRecordType(Record);
2228  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
2229    assert(!Enum->getPreviousDecl() &&
2230           "enum has previous declaration");
2231    return getEnumType(Enum);
2232  } else if (const UnresolvedUsingTypenameDecl *Using =
2233               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
2234    Type *newType = new (*this, TypeAlignment) UnresolvedUsingType(Using);
2235    Decl->TypeForDecl = newType;
2236    Types.push_back(newType);
2237  } else
2238    llvm_unreachable("TypeDecl without a type?");
2239
2240  return QualType(Decl->TypeForDecl, 0);
2241}
2242
2243/// getTypedefType - Return the unique reference to the type for the
2244/// specified typedef name decl.
2245QualType
2246ASTContext::getTypedefType(const TypedefNameDecl *Decl,
2247                           QualType Canonical) const {
2248  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2249
2250  if (Canonical.isNull())
2251    Canonical = getCanonicalType(Decl->getUnderlyingType());
2252  TypedefType *newType = new(*this, TypeAlignment)
2253    TypedefType(Type::Typedef, Decl, Canonical);
2254  Decl->TypeForDecl = newType;
2255  Types.push_back(newType);
2256  return QualType(newType, 0);
2257}
2258
2259QualType ASTContext::getRecordType(const RecordDecl *Decl) const {
2260  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2261
2262  if (const RecordDecl *PrevDecl = Decl->getPreviousDecl())
2263    if (PrevDecl->TypeForDecl)
2264      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2265
2266  RecordType *newType = new (*this, TypeAlignment) RecordType(Decl);
2267  Decl->TypeForDecl = newType;
2268  Types.push_back(newType);
2269  return QualType(newType, 0);
2270}
2271
2272QualType ASTContext::getEnumType(const EnumDecl *Decl) const {
2273  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2274
2275  if (const EnumDecl *PrevDecl = Decl->getPreviousDecl())
2276    if (PrevDecl->TypeForDecl)
2277      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2278
2279  EnumType *newType = new (*this, TypeAlignment) EnumType(Decl);
2280  Decl->TypeForDecl = newType;
2281  Types.push_back(newType);
2282  return QualType(newType, 0);
2283}
2284
2285QualType ASTContext::getAttributedType(AttributedType::Kind attrKind,
2286                                       QualType modifiedType,
2287                                       QualType equivalentType) {
2288  llvm::FoldingSetNodeID id;
2289  AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
2290
2291  void *insertPos = 0;
2292  AttributedType *type = AttributedTypes.FindNodeOrInsertPos(id, insertPos);
2293  if (type) return QualType(type, 0);
2294
2295  QualType canon = getCanonicalType(equivalentType);
2296  type = new (*this, TypeAlignment)
2297           AttributedType(canon, attrKind, modifiedType, equivalentType);
2298
2299  Types.push_back(type);
2300  AttributedTypes.InsertNode(type, insertPos);
2301
2302  return QualType(type, 0);
2303}
2304
2305
2306/// \brief Retrieve a substitution-result type.
2307QualType
2308ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
2309                                         QualType Replacement) const {
2310  assert(Replacement.isCanonical()
2311         && "replacement types must always be canonical");
2312
2313  llvm::FoldingSetNodeID ID;
2314  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
2315  void *InsertPos = 0;
2316  SubstTemplateTypeParmType *SubstParm
2317    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2318
2319  if (!SubstParm) {
2320    SubstParm = new (*this, TypeAlignment)
2321      SubstTemplateTypeParmType(Parm, Replacement);
2322    Types.push_back(SubstParm);
2323    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2324  }
2325
2326  return QualType(SubstParm, 0);
2327}
2328
2329/// \brief Retrieve a
2330QualType ASTContext::getSubstTemplateTypeParmPackType(
2331                                          const TemplateTypeParmType *Parm,
2332                                              const TemplateArgument &ArgPack) {
2333#ifndef NDEBUG
2334  for (TemplateArgument::pack_iterator P = ArgPack.pack_begin(),
2335                                    PEnd = ArgPack.pack_end();
2336       P != PEnd; ++P) {
2337    assert(P->getKind() == TemplateArgument::Type &&"Pack contains a non-type");
2338    assert(P->getAsType().isCanonical() && "Pack contains non-canonical type");
2339  }
2340#endif
2341
2342  llvm::FoldingSetNodeID ID;
2343  SubstTemplateTypeParmPackType::Profile(ID, Parm, ArgPack);
2344  void *InsertPos = 0;
2345  if (SubstTemplateTypeParmPackType *SubstParm
2346        = SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos))
2347    return QualType(SubstParm, 0);
2348
2349  QualType Canon;
2350  if (!Parm->isCanonicalUnqualified()) {
2351    Canon = getCanonicalType(QualType(Parm, 0));
2352    Canon = getSubstTemplateTypeParmPackType(cast<TemplateTypeParmType>(Canon),
2353                                             ArgPack);
2354    SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos);
2355  }
2356
2357  SubstTemplateTypeParmPackType *SubstParm
2358    = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
2359                                                               ArgPack);
2360  Types.push_back(SubstParm);
2361  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2362  return QualType(SubstParm, 0);
2363}
2364
2365/// \brief Retrieve the template type parameter type for a template
2366/// parameter or parameter pack with the given depth, index, and (optionally)
2367/// name.
2368QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
2369                                             bool ParameterPack,
2370                                             TemplateTypeParmDecl *TTPDecl) const {
2371  llvm::FoldingSetNodeID ID;
2372  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, TTPDecl);
2373  void *InsertPos = 0;
2374  TemplateTypeParmType *TypeParm
2375    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2376
2377  if (TypeParm)
2378    return QualType(TypeParm, 0);
2379
2380  if (TTPDecl) {
2381    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
2382    TypeParm = new (*this, TypeAlignment) TemplateTypeParmType(TTPDecl, Canon);
2383
2384    TemplateTypeParmType *TypeCheck
2385      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2386    assert(!TypeCheck && "Template type parameter canonical type broken");
2387    (void)TypeCheck;
2388  } else
2389    TypeParm = new (*this, TypeAlignment)
2390      TemplateTypeParmType(Depth, Index, ParameterPack);
2391
2392  Types.push_back(TypeParm);
2393  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
2394
2395  return QualType(TypeParm, 0);
2396}
2397
2398TypeSourceInfo *
2399ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
2400                                              SourceLocation NameLoc,
2401                                        const TemplateArgumentListInfo &Args,
2402                                              QualType Underlying) const {
2403  assert(!Name.getAsDependentTemplateName() &&
2404         "No dependent template names here!");
2405  QualType TST = getTemplateSpecializationType(Name, Args, Underlying);
2406
2407  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
2408  TemplateSpecializationTypeLoc TL
2409    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
2410  TL.setTemplateNameLoc(NameLoc);
2411  TL.setLAngleLoc(Args.getLAngleLoc());
2412  TL.setRAngleLoc(Args.getRAngleLoc());
2413  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
2414    TL.setArgLocInfo(i, Args[i].getLocInfo());
2415  return DI;
2416}
2417
2418QualType
2419ASTContext::getTemplateSpecializationType(TemplateName Template,
2420                                          const TemplateArgumentListInfo &Args,
2421                                          QualType Underlying) const {
2422  assert(!Template.getAsDependentTemplateName() &&
2423         "No dependent template names here!");
2424
2425  unsigned NumArgs = Args.size();
2426
2427  SmallVector<TemplateArgument, 4> ArgVec;
2428  ArgVec.reserve(NumArgs);
2429  for (unsigned i = 0; i != NumArgs; ++i)
2430    ArgVec.push_back(Args[i].getArgument());
2431
2432  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
2433                                       Underlying);
2434}
2435
2436QualType
2437ASTContext::getTemplateSpecializationType(TemplateName Template,
2438                                          const TemplateArgument *Args,
2439                                          unsigned NumArgs,
2440                                          QualType Underlying) const {
2441  assert(!Template.getAsDependentTemplateName() &&
2442         "No dependent template names here!");
2443  // Look through qualified template names.
2444  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2445    Template = TemplateName(QTN->getTemplateDecl());
2446
2447  bool isTypeAlias =
2448    Template.getAsTemplateDecl() &&
2449    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
2450
2451  QualType CanonType;
2452  if (!Underlying.isNull())
2453    CanonType = getCanonicalType(Underlying);
2454  else {
2455    assert(!isTypeAlias &&
2456           "Underlying type for template alias must be computed by caller");
2457    CanonType = getCanonicalTemplateSpecializationType(Template, Args,
2458                                                       NumArgs);
2459  }
2460
2461  // Allocate the (non-canonical) template specialization type, but don't
2462  // try to unique it: these types typically have location information that
2463  // we don't unique and don't want to lose.
2464  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
2465                       sizeof(TemplateArgument) * NumArgs +
2466                       (isTypeAlias ? sizeof(QualType) : 0),
2467                       TypeAlignment);
2468  TemplateSpecializationType *Spec
2469    = new (Mem) TemplateSpecializationType(Template,
2470                                           Args, NumArgs,
2471                                           CanonType,
2472                                         isTypeAlias ? Underlying : QualType());
2473
2474  Types.push_back(Spec);
2475  return QualType(Spec, 0);
2476}
2477
2478QualType
2479ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
2480                                                   const TemplateArgument *Args,
2481                                                   unsigned NumArgs) const {
2482  assert(!Template.getAsDependentTemplateName() &&
2483         "No dependent template names here!");
2484  assert((!Template.getAsTemplateDecl() ||
2485          !isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl())) &&
2486         "Underlying type for template alias must be computed by caller");
2487
2488  // Look through qualified template names.
2489  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2490    Template = TemplateName(QTN->getTemplateDecl());
2491
2492  // Build the canonical template specialization type.
2493  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
2494  SmallVector<TemplateArgument, 4> CanonArgs;
2495  CanonArgs.reserve(NumArgs);
2496  for (unsigned I = 0; I != NumArgs; ++I)
2497    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
2498
2499  // Determine whether this canonical template specialization type already
2500  // exists.
2501  llvm::FoldingSetNodeID ID;
2502  TemplateSpecializationType::Profile(ID, CanonTemplate,
2503                                      CanonArgs.data(), NumArgs, *this);
2504
2505  void *InsertPos = 0;
2506  TemplateSpecializationType *Spec
2507    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2508
2509  if (!Spec) {
2510    // Allocate a new canonical template specialization type.
2511    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2512                          sizeof(TemplateArgument) * NumArgs),
2513                         TypeAlignment);
2514    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
2515                                                CanonArgs.data(), NumArgs,
2516                                                QualType(), QualType());
2517    Types.push_back(Spec);
2518    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
2519  }
2520
2521  assert(Spec->isDependentType() &&
2522         "Non-dependent template-id type must have a canonical type");
2523  return QualType(Spec, 0);
2524}
2525
2526QualType
2527ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
2528                              NestedNameSpecifier *NNS,
2529                              QualType NamedType) const {
2530  llvm::FoldingSetNodeID ID;
2531  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2532
2533  void *InsertPos = 0;
2534  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2535  if (T)
2536    return QualType(T, 0);
2537
2538  QualType Canon = NamedType;
2539  if (!Canon.isCanonical()) {
2540    Canon = getCanonicalType(NamedType);
2541    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2542    assert(!CheckT && "Elaborated canonical type broken");
2543    (void)CheckT;
2544  }
2545
2546  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2547  Types.push_back(T);
2548  ElaboratedTypes.InsertNode(T, InsertPos);
2549  return QualType(T, 0);
2550}
2551
2552QualType
2553ASTContext::getParenType(QualType InnerType) const {
2554  llvm::FoldingSetNodeID ID;
2555  ParenType::Profile(ID, InnerType);
2556
2557  void *InsertPos = 0;
2558  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2559  if (T)
2560    return QualType(T, 0);
2561
2562  QualType Canon = InnerType;
2563  if (!Canon.isCanonical()) {
2564    Canon = getCanonicalType(InnerType);
2565    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2566    assert(!CheckT && "Paren canonical type broken");
2567    (void)CheckT;
2568  }
2569
2570  T = new (*this) ParenType(InnerType, Canon);
2571  Types.push_back(T);
2572  ParenTypes.InsertNode(T, InsertPos);
2573  return QualType(T, 0);
2574}
2575
2576QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2577                                          NestedNameSpecifier *NNS,
2578                                          const IdentifierInfo *Name,
2579                                          QualType Canon) const {
2580  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2581
2582  if (Canon.isNull()) {
2583    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2584    ElaboratedTypeKeyword CanonKeyword = Keyword;
2585    if (Keyword == ETK_None)
2586      CanonKeyword = ETK_Typename;
2587
2588    if (CanonNNS != NNS || CanonKeyword != Keyword)
2589      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2590  }
2591
2592  llvm::FoldingSetNodeID ID;
2593  DependentNameType::Profile(ID, Keyword, NNS, Name);
2594
2595  void *InsertPos = 0;
2596  DependentNameType *T
2597    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2598  if (T)
2599    return QualType(T, 0);
2600
2601  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2602  Types.push_back(T);
2603  DependentNameTypes.InsertNode(T, InsertPos);
2604  return QualType(T, 0);
2605}
2606
2607QualType
2608ASTContext::getDependentTemplateSpecializationType(
2609                                 ElaboratedTypeKeyword Keyword,
2610                                 NestedNameSpecifier *NNS,
2611                                 const IdentifierInfo *Name,
2612                                 const TemplateArgumentListInfo &Args) const {
2613  // TODO: avoid this copy
2614  SmallVector<TemplateArgument, 16> ArgCopy;
2615  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2616    ArgCopy.push_back(Args[I].getArgument());
2617  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2618                                                ArgCopy.size(),
2619                                                ArgCopy.data());
2620}
2621
2622QualType
2623ASTContext::getDependentTemplateSpecializationType(
2624                                 ElaboratedTypeKeyword Keyword,
2625                                 NestedNameSpecifier *NNS,
2626                                 const IdentifierInfo *Name,
2627                                 unsigned NumArgs,
2628                                 const TemplateArgument *Args) const {
2629  assert((!NNS || NNS->isDependent()) &&
2630         "nested-name-specifier must be dependent");
2631
2632  llvm::FoldingSetNodeID ID;
2633  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2634                                               Name, NumArgs, Args);
2635
2636  void *InsertPos = 0;
2637  DependentTemplateSpecializationType *T
2638    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2639  if (T)
2640    return QualType(T, 0);
2641
2642  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2643
2644  ElaboratedTypeKeyword CanonKeyword = Keyword;
2645  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2646
2647  bool AnyNonCanonArgs = false;
2648  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2649  for (unsigned I = 0; I != NumArgs; ++I) {
2650    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2651    if (!CanonArgs[I].structurallyEquals(Args[I]))
2652      AnyNonCanonArgs = true;
2653  }
2654
2655  QualType Canon;
2656  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2657    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2658                                                   Name, NumArgs,
2659                                                   CanonArgs.data());
2660
2661    // Find the insert position again.
2662    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2663  }
2664
2665  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2666                        sizeof(TemplateArgument) * NumArgs),
2667                       TypeAlignment);
2668  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2669                                                    Name, NumArgs, Args, Canon);
2670  Types.push_back(T);
2671  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2672  return QualType(T, 0);
2673}
2674
2675QualType ASTContext::getPackExpansionType(QualType Pattern,
2676                                      llvm::Optional<unsigned> NumExpansions) {
2677  llvm::FoldingSetNodeID ID;
2678  PackExpansionType::Profile(ID, Pattern, NumExpansions);
2679
2680  assert(Pattern->containsUnexpandedParameterPack() &&
2681         "Pack expansions must expand one or more parameter packs");
2682  void *InsertPos = 0;
2683  PackExpansionType *T
2684    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2685  if (T)
2686    return QualType(T, 0);
2687
2688  QualType Canon;
2689  if (!Pattern.isCanonical()) {
2690    Canon = getPackExpansionType(getCanonicalType(Pattern), NumExpansions);
2691
2692    // Find the insert position again.
2693    PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2694  }
2695
2696  T = new (*this) PackExpansionType(Pattern, Canon, NumExpansions);
2697  Types.push_back(T);
2698  PackExpansionTypes.InsertNode(T, InsertPos);
2699  return QualType(T, 0);
2700}
2701
2702/// CmpProtocolNames - Comparison predicate for sorting protocols
2703/// alphabetically.
2704static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2705                            const ObjCProtocolDecl *RHS) {
2706  return LHS->getDeclName() < RHS->getDeclName();
2707}
2708
2709static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2710                                unsigned NumProtocols) {
2711  if (NumProtocols == 0) return true;
2712
2713  if (Protocols[0]->getCanonicalDecl() != Protocols[0])
2714    return false;
2715
2716  for (unsigned i = 1; i != NumProtocols; ++i)
2717    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]) ||
2718        Protocols[i]->getCanonicalDecl() != Protocols[i])
2719      return false;
2720  return true;
2721}
2722
2723static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2724                                   unsigned &NumProtocols) {
2725  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2726
2727  // Sort protocols, keyed by name.
2728  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2729
2730  // Canonicalize.
2731  for (unsigned I = 0, N = NumProtocols; I != N; ++I)
2732    Protocols[I] = Protocols[I]->getCanonicalDecl();
2733
2734  // Remove duplicates.
2735  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2736  NumProtocols = ProtocolsEnd-Protocols;
2737}
2738
2739QualType ASTContext::getObjCObjectType(QualType BaseType,
2740                                       ObjCProtocolDecl * const *Protocols,
2741                                       unsigned NumProtocols) const {
2742  // If the base type is an interface and there aren't any protocols
2743  // to add, then the interface type will do just fine.
2744  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2745    return BaseType;
2746
2747  // Look in the folding set for an existing type.
2748  llvm::FoldingSetNodeID ID;
2749  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2750  void *InsertPos = 0;
2751  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2752    return QualType(QT, 0);
2753
2754  // Build the canonical type, which has the canonical base type and
2755  // a sorted-and-uniqued list of protocols.
2756  QualType Canonical;
2757  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2758  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2759    if (!ProtocolsSorted) {
2760      SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2761                                                     Protocols + NumProtocols);
2762      unsigned UniqueCount = NumProtocols;
2763
2764      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2765      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2766                                    &Sorted[0], UniqueCount);
2767    } else {
2768      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2769                                    Protocols, NumProtocols);
2770    }
2771
2772    // Regenerate InsertPos.
2773    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2774  }
2775
2776  unsigned Size = sizeof(ObjCObjectTypeImpl);
2777  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2778  void *Mem = Allocate(Size, TypeAlignment);
2779  ObjCObjectTypeImpl *T =
2780    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2781
2782  Types.push_back(T);
2783  ObjCObjectTypes.InsertNode(T, InsertPos);
2784  return QualType(T, 0);
2785}
2786
2787/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2788/// the given object type.
2789QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
2790  llvm::FoldingSetNodeID ID;
2791  ObjCObjectPointerType::Profile(ID, ObjectT);
2792
2793  void *InsertPos = 0;
2794  if (ObjCObjectPointerType *QT =
2795              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2796    return QualType(QT, 0);
2797
2798  // Find the canonical object type.
2799  QualType Canonical;
2800  if (!ObjectT.isCanonical()) {
2801    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2802
2803    // Regenerate InsertPos.
2804    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2805  }
2806
2807  // No match.
2808  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2809  ObjCObjectPointerType *QType =
2810    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2811
2812  Types.push_back(QType);
2813  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2814  return QualType(QType, 0);
2815}
2816
2817/// getObjCInterfaceType - Return the unique reference to the type for the
2818/// specified ObjC interface decl. The list of protocols is optional.
2819QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
2820                                          ObjCInterfaceDecl *PrevDecl) const {
2821  if (Decl->TypeForDecl)
2822    return QualType(Decl->TypeForDecl, 0);
2823
2824  if (PrevDecl) {
2825    assert(PrevDecl->TypeForDecl && "previous decl has no TypeForDecl");
2826    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2827    return QualType(PrevDecl->TypeForDecl, 0);
2828  }
2829
2830  // Prefer the definition, if there is one.
2831  if (const ObjCInterfaceDecl *Def = Decl->getDefinition())
2832    Decl = Def;
2833
2834  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2835  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2836  Decl->TypeForDecl = T;
2837  Types.push_back(T);
2838  return QualType(T, 0);
2839}
2840
2841/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2842/// TypeOfExprType AST's (since expression's are never shared). For example,
2843/// multiple declarations that refer to "typeof(x)" all contain different
2844/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2845/// on canonical type's (which are always unique).
2846QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
2847  TypeOfExprType *toe;
2848  if (tofExpr->isTypeDependent()) {
2849    llvm::FoldingSetNodeID ID;
2850    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2851
2852    void *InsertPos = 0;
2853    DependentTypeOfExprType *Canon
2854      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2855    if (Canon) {
2856      // We already have a "canonical" version of an identical, dependent
2857      // typeof(expr) type. Use that as our canonical type.
2858      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2859                                          QualType((TypeOfExprType*)Canon, 0));
2860    } else {
2861      // Build a new, canonical typeof(expr) type.
2862      Canon
2863        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2864      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2865      toe = Canon;
2866    }
2867  } else {
2868    QualType Canonical = getCanonicalType(tofExpr->getType());
2869    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2870  }
2871  Types.push_back(toe);
2872  return QualType(toe, 0);
2873}
2874
2875/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2876/// TypeOfType AST's. The only motivation to unique these nodes would be
2877/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2878/// an issue. This doesn't effect the type checker, since it operates
2879/// on canonical type's (which are always unique).
2880QualType ASTContext::getTypeOfType(QualType tofType) const {
2881  QualType Canonical = getCanonicalType(tofType);
2882  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2883  Types.push_back(tot);
2884  return QualType(tot, 0);
2885}
2886
2887/// getDecltypeForExpr - Given an expr, will return the decltype for that
2888/// expression, according to the rules in C++0x [dcl.type.simple]p4
2889static QualType getDecltypeForExpr(const Expr *e, const ASTContext &Context) {
2890  if (e->isTypeDependent())
2891    return Context.DependentTy;
2892
2893  // If e is an id expression or a class member access, decltype(e) is defined
2894  // as the type of the entity named by e.
2895  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2896    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2897      return VD->getType();
2898  }
2899  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2900    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2901      return FD->getType();
2902  }
2903  // If e is a function call or an invocation of an overloaded operator,
2904  // (parentheses around e are ignored), decltype(e) is defined as the
2905  // return type of that function.
2906  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2907    return CE->getCallReturnType();
2908
2909  QualType T = e->getType();
2910
2911  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2912  // defined as T&, otherwise decltype(e) is defined as T.
2913  if (e->isLValue())
2914    T = Context.getLValueReferenceType(T);
2915
2916  return T;
2917}
2918
2919/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2920/// DecltypeType AST's. The only motivation to unique these nodes would be
2921/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2922/// an issue. This doesn't effect the type checker, since it operates
2923/// on canonical types (which are always unique).
2924QualType ASTContext::getDecltypeType(Expr *e) const {
2925  DecltypeType *dt;
2926
2927  // C++0x [temp.type]p2:
2928  //   If an expression e involves a template parameter, decltype(e) denotes a
2929  //   unique dependent type. Two such decltype-specifiers refer to the same
2930  //   type only if their expressions are equivalent (14.5.6.1).
2931  if (e->isInstantiationDependent()) {
2932    llvm::FoldingSetNodeID ID;
2933    DependentDecltypeType::Profile(ID, *this, e);
2934
2935    void *InsertPos = 0;
2936    DependentDecltypeType *Canon
2937      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2938    if (Canon) {
2939      // We already have a "canonical" version of an equivalent, dependent
2940      // decltype type. Use that as our canonical type.
2941      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2942                                       QualType((DecltypeType*)Canon, 0));
2943    } else {
2944      // Build a new, canonical typeof(expr) type.
2945      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2946      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2947      dt = Canon;
2948    }
2949  } else {
2950    QualType T = getDecltypeForExpr(e, *this);
2951    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2952  }
2953  Types.push_back(dt);
2954  return QualType(dt, 0);
2955}
2956
2957/// getUnaryTransformationType - We don't unique these, since the memory
2958/// savings are minimal and these are rare.
2959QualType ASTContext::getUnaryTransformType(QualType BaseType,
2960                                           QualType UnderlyingType,
2961                                           UnaryTransformType::UTTKind Kind)
2962    const {
2963  UnaryTransformType *Ty =
2964    new (*this, TypeAlignment) UnaryTransformType (BaseType, UnderlyingType,
2965                                                   Kind,
2966                                 UnderlyingType->isDependentType() ?
2967                                    QualType() : UnderlyingType);
2968  Types.push_back(Ty);
2969  return QualType(Ty, 0);
2970}
2971
2972/// getAutoType - We only unique auto types after they've been deduced.
2973QualType ASTContext::getAutoType(QualType DeducedType) const {
2974  void *InsertPos = 0;
2975  if (!DeducedType.isNull()) {
2976    // Look in the folding set for an existing type.
2977    llvm::FoldingSetNodeID ID;
2978    AutoType::Profile(ID, DeducedType);
2979    if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
2980      return QualType(AT, 0);
2981  }
2982
2983  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType);
2984  Types.push_back(AT);
2985  if (InsertPos)
2986    AutoTypes.InsertNode(AT, InsertPos);
2987  return QualType(AT, 0);
2988}
2989
2990/// getAtomicType - Return the uniqued reference to the atomic type for
2991/// the given value type.
2992QualType ASTContext::getAtomicType(QualType T) const {
2993  // Unique pointers, to guarantee there is only one pointer of a particular
2994  // structure.
2995  llvm::FoldingSetNodeID ID;
2996  AtomicType::Profile(ID, T);
2997
2998  void *InsertPos = 0;
2999  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
3000    return QualType(AT, 0);
3001
3002  // If the atomic value type isn't canonical, this won't be a canonical type
3003  // either, so fill in the canonical type field.
3004  QualType Canonical;
3005  if (!T.isCanonical()) {
3006    Canonical = getAtomicType(getCanonicalType(T));
3007
3008    // Get the new insert position for the node we care about.
3009    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
3010    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
3011  }
3012  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
3013  Types.push_back(New);
3014  AtomicTypes.InsertNode(New, InsertPos);
3015  return QualType(New, 0);
3016}
3017
3018/// getAutoDeductType - Get type pattern for deducing against 'auto'.
3019QualType ASTContext::getAutoDeductType() const {
3020  if (AutoDeductTy.isNull())
3021    AutoDeductTy = getAutoType(QualType());
3022  assert(!AutoDeductTy.isNull() && "can't build 'auto' pattern");
3023  return AutoDeductTy;
3024}
3025
3026/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
3027QualType ASTContext::getAutoRRefDeductType() const {
3028  if (AutoRRefDeductTy.isNull())
3029    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
3030  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
3031  return AutoRRefDeductTy;
3032}
3033
3034/// getTagDeclType - Return the unique reference to the type for the
3035/// specified TagDecl (struct/union/class/enum) decl.
3036QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
3037  assert (Decl);
3038  // FIXME: What is the design on getTagDeclType when it requires casting
3039  // away const?  mutable?
3040  return getTypeDeclType(const_cast<TagDecl*>(Decl));
3041}
3042
3043/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
3044/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
3045/// needs to agree with the definition in <stddef.h>.
3046CanQualType ASTContext::getSizeType() const {
3047  return getFromTargetType(Target->getSizeType());
3048}
3049
3050/// getIntMaxType - Return the unique type for "intmax_t" (C99 7.18.1.5).
3051CanQualType ASTContext::getIntMaxType() const {
3052  return getFromTargetType(Target->getIntMaxType());
3053}
3054
3055/// getUIntMaxType - Return the unique type for "uintmax_t" (C99 7.18.1.5).
3056CanQualType ASTContext::getUIntMaxType() const {
3057  return getFromTargetType(Target->getUIntMaxType());
3058}
3059
3060/// getSignedWCharType - Return the type of "signed wchar_t".
3061/// Used when in C++, as a GCC extension.
3062QualType ASTContext::getSignedWCharType() const {
3063  // FIXME: derive from "Target" ?
3064  return WCharTy;
3065}
3066
3067/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
3068/// Used when in C++, as a GCC extension.
3069QualType ASTContext::getUnsignedWCharType() const {
3070  // FIXME: derive from "Target" ?
3071  return UnsignedIntTy;
3072}
3073
3074/// getPointerDiffType - Return the unique type for "ptrdiff_t" (C99 7.17)
3075/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
3076QualType ASTContext::getPointerDiffType() const {
3077  return getFromTargetType(Target->getPtrDiffType(0));
3078}
3079
3080//===----------------------------------------------------------------------===//
3081//                              Type Operators
3082//===----------------------------------------------------------------------===//
3083
3084CanQualType ASTContext::getCanonicalParamType(QualType T) const {
3085  // Push qualifiers into arrays, and then discard any remaining
3086  // qualifiers.
3087  T = getCanonicalType(T);
3088  T = getVariableArrayDecayedType(T);
3089  const Type *Ty = T.getTypePtr();
3090  QualType Result;
3091  if (isa<ArrayType>(Ty)) {
3092    Result = getArrayDecayedType(QualType(Ty,0));
3093  } else if (isa<FunctionType>(Ty)) {
3094    Result = getPointerType(QualType(Ty, 0));
3095  } else {
3096    Result = QualType(Ty, 0);
3097  }
3098
3099  return CanQualType::CreateUnsafe(Result);
3100}
3101
3102QualType ASTContext::getUnqualifiedArrayType(QualType type,
3103                                             Qualifiers &quals) {
3104  SplitQualType splitType = type.getSplitUnqualifiedType();
3105
3106  // FIXME: getSplitUnqualifiedType() actually walks all the way to
3107  // the unqualified desugared type and then drops it on the floor.
3108  // We then have to strip that sugar back off with
3109  // getUnqualifiedDesugaredType(), which is silly.
3110  const ArrayType *AT =
3111    dyn_cast<ArrayType>(splitType.first->getUnqualifiedDesugaredType());
3112
3113  // If we don't have an array, just use the results in splitType.
3114  if (!AT) {
3115    quals = splitType.second;
3116    return QualType(splitType.first, 0);
3117  }
3118
3119  // Otherwise, recurse on the array's element type.
3120  QualType elementType = AT->getElementType();
3121  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
3122
3123  // If that didn't change the element type, AT has no qualifiers, so we
3124  // can just use the results in splitType.
3125  if (elementType == unqualElementType) {
3126    assert(quals.empty()); // from the recursive call
3127    quals = splitType.second;
3128    return QualType(splitType.first, 0);
3129  }
3130
3131  // Otherwise, add in the qualifiers from the outermost type, then
3132  // build the type back up.
3133  quals.addConsistentQualifiers(splitType.second);
3134
3135  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
3136    return getConstantArrayType(unqualElementType, CAT->getSize(),
3137                                CAT->getSizeModifier(), 0);
3138  }
3139
3140  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
3141    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
3142  }
3143
3144  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
3145    return getVariableArrayType(unqualElementType,
3146                                VAT->getSizeExpr(),
3147                                VAT->getSizeModifier(),
3148                                VAT->getIndexTypeCVRQualifiers(),
3149                                VAT->getBracketsRange());
3150  }
3151
3152  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
3153  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
3154                                    DSAT->getSizeModifier(), 0,
3155                                    SourceRange());
3156}
3157
3158/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
3159/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
3160/// they point to and return true. If T1 and T2 aren't pointer types
3161/// or pointer-to-member types, or if they are not similar at this
3162/// level, returns false and leaves T1 and T2 unchanged. Top-level
3163/// qualifiers on T1 and T2 are ignored. This function will typically
3164/// be called in a loop that successively "unwraps" pointer and
3165/// pointer-to-member types to compare them at each level.
3166bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
3167  const PointerType *T1PtrType = T1->getAs<PointerType>(),
3168                    *T2PtrType = T2->getAs<PointerType>();
3169  if (T1PtrType && T2PtrType) {
3170    T1 = T1PtrType->getPointeeType();
3171    T2 = T2PtrType->getPointeeType();
3172    return true;
3173  }
3174
3175  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
3176                          *T2MPType = T2->getAs<MemberPointerType>();
3177  if (T1MPType && T2MPType &&
3178      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
3179                             QualType(T2MPType->getClass(), 0))) {
3180    T1 = T1MPType->getPointeeType();
3181    T2 = T2MPType->getPointeeType();
3182    return true;
3183  }
3184
3185  if (getLangOptions().ObjC1) {
3186    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
3187                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
3188    if (T1OPType && T2OPType) {
3189      T1 = T1OPType->getPointeeType();
3190      T2 = T2OPType->getPointeeType();
3191      return true;
3192    }
3193  }
3194
3195  // FIXME: Block pointers, too?
3196
3197  return false;
3198}
3199
3200DeclarationNameInfo
3201ASTContext::getNameForTemplate(TemplateName Name,
3202                               SourceLocation NameLoc) const {
3203  switch (Name.getKind()) {
3204  case TemplateName::QualifiedTemplate:
3205  case TemplateName::Template:
3206    // DNInfo work in progress: CHECKME: what about DNLoc?
3207    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
3208                               NameLoc);
3209
3210  case TemplateName::OverloadedTemplate: {
3211    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
3212    // DNInfo work in progress: CHECKME: what about DNLoc?
3213    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
3214  }
3215
3216  case TemplateName::DependentTemplate: {
3217    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3218    DeclarationName DName;
3219    if (DTN->isIdentifier()) {
3220      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
3221      return DeclarationNameInfo(DName, NameLoc);
3222    } else {
3223      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
3224      // DNInfo work in progress: FIXME: source locations?
3225      DeclarationNameLoc DNLoc;
3226      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
3227      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
3228      return DeclarationNameInfo(DName, NameLoc, DNLoc);
3229    }
3230  }
3231
3232  case TemplateName::SubstTemplateTemplateParm: {
3233    SubstTemplateTemplateParmStorage *subst
3234      = Name.getAsSubstTemplateTemplateParm();
3235    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
3236                               NameLoc);
3237  }
3238
3239  case TemplateName::SubstTemplateTemplateParmPack: {
3240    SubstTemplateTemplateParmPackStorage *subst
3241      = Name.getAsSubstTemplateTemplateParmPack();
3242    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
3243                               NameLoc);
3244  }
3245  }
3246
3247  llvm_unreachable("bad template name kind!");
3248}
3249
3250TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
3251  switch (Name.getKind()) {
3252  case TemplateName::QualifiedTemplate:
3253  case TemplateName::Template: {
3254    TemplateDecl *Template = Name.getAsTemplateDecl();
3255    if (TemplateTemplateParmDecl *TTP
3256          = dyn_cast<TemplateTemplateParmDecl>(Template))
3257      Template = getCanonicalTemplateTemplateParmDecl(TTP);
3258
3259    // The canonical template name is the canonical template declaration.
3260    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
3261  }
3262
3263  case TemplateName::OverloadedTemplate:
3264    llvm_unreachable("cannot canonicalize overloaded template");
3265
3266  case TemplateName::DependentTemplate: {
3267    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3268    assert(DTN && "Non-dependent template names must refer to template decls.");
3269    return DTN->CanonicalTemplateName;
3270  }
3271
3272  case TemplateName::SubstTemplateTemplateParm: {
3273    SubstTemplateTemplateParmStorage *subst
3274      = Name.getAsSubstTemplateTemplateParm();
3275    return getCanonicalTemplateName(subst->getReplacement());
3276  }
3277
3278  case TemplateName::SubstTemplateTemplateParmPack: {
3279    SubstTemplateTemplateParmPackStorage *subst
3280                                  = Name.getAsSubstTemplateTemplateParmPack();
3281    TemplateTemplateParmDecl *canonParameter
3282      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
3283    TemplateArgument canonArgPack
3284      = getCanonicalTemplateArgument(subst->getArgumentPack());
3285    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
3286  }
3287  }
3288
3289  llvm_unreachable("bad template name!");
3290}
3291
3292bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
3293  X = getCanonicalTemplateName(X);
3294  Y = getCanonicalTemplateName(Y);
3295  return X.getAsVoidPointer() == Y.getAsVoidPointer();
3296}
3297
3298TemplateArgument
3299ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
3300  switch (Arg.getKind()) {
3301    case TemplateArgument::Null:
3302      return Arg;
3303
3304    case TemplateArgument::Expression:
3305      return Arg;
3306
3307    case TemplateArgument::Declaration:
3308      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
3309
3310    case TemplateArgument::Template:
3311      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
3312
3313    case TemplateArgument::TemplateExpansion:
3314      return TemplateArgument(getCanonicalTemplateName(
3315                                         Arg.getAsTemplateOrTemplatePattern()),
3316                              Arg.getNumTemplateExpansions());
3317
3318    case TemplateArgument::Integral:
3319      return TemplateArgument(*Arg.getAsIntegral(),
3320                              getCanonicalType(Arg.getIntegralType()));
3321
3322    case TemplateArgument::Type:
3323      return TemplateArgument(getCanonicalType(Arg.getAsType()));
3324
3325    case TemplateArgument::Pack: {
3326      if (Arg.pack_size() == 0)
3327        return Arg;
3328
3329      TemplateArgument *CanonArgs
3330        = new (*this) TemplateArgument[Arg.pack_size()];
3331      unsigned Idx = 0;
3332      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
3333                                        AEnd = Arg.pack_end();
3334           A != AEnd; (void)++A, ++Idx)
3335        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
3336
3337      return TemplateArgument(CanonArgs, Arg.pack_size());
3338    }
3339  }
3340
3341  // Silence GCC warning
3342  llvm_unreachable("Unhandled template argument kind");
3343}
3344
3345NestedNameSpecifier *
3346ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
3347  if (!NNS)
3348    return 0;
3349
3350  switch (NNS->getKind()) {
3351  case NestedNameSpecifier::Identifier:
3352    // Canonicalize the prefix but keep the identifier the same.
3353    return NestedNameSpecifier::Create(*this,
3354                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
3355                                       NNS->getAsIdentifier());
3356
3357  case NestedNameSpecifier::Namespace:
3358    // A namespace is canonical; build a nested-name-specifier with
3359    // this namespace and no prefix.
3360    return NestedNameSpecifier::Create(*this, 0,
3361                                 NNS->getAsNamespace()->getOriginalNamespace());
3362
3363  case NestedNameSpecifier::NamespaceAlias:
3364    // A namespace is canonical; build a nested-name-specifier with
3365    // this namespace and no prefix.
3366    return NestedNameSpecifier::Create(*this, 0,
3367                                    NNS->getAsNamespaceAlias()->getNamespace()
3368                                                      ->getOriginalNamespace());
3369
3370  case NestedNameSpecifier::TypeSpec:
3371  case NestedNameSpecifier::TypeSpecWithTemplate: {
3372    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
3373
3374    // If we have some kind of dependent-named type (e.g., "typename T::type"),
3375    // break it apart into its prefix and identifier, then reconsititute those
3376    // as the canonical nested-name-specifier. This is required to canonicalize
3377    // a dependent nested-name-specifier involving typedefs of dependent-name
3378    // types, e.g.,
3379    //   typedef typename T::type T1;
3380    //   typedef typename T1::type T2;
3381    if (const DependentNameType *DNT = T->getAs<DependentNameType>()) {
3382      NestedNameSpecifier *Prefix
3383        = getCanonicalNestedNameSpecifier(DNT->getQualifier());
3384      return NestedNameSpecifier::Create(*this, Prefix,
3385                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
3386    }
3387
3388    // Do the same thing as above, but with dependent-named specializations.
3389    if (const DependentTemplateSpecializationType *DTST
3390          = T->getAs<DependentTemplateSpecializationType>()) {
3391      NestedNameSpecifier *Prefix
3392        = getCanonicalNestedNameSpecifier(DTST->getQualifier());
3393
3394      T = getDependentTemplateSpecializationType(DTST->getKeyword(),
3395                                                 Prefix, DTST->getIdentifier(),
3396                                                 DTST->getNumArgs(),
3397                                                 DTST->getArgs());
3398      T = getCanonicalType(T);
3399    }
3400
3401    return NestedNameSpecifier::Create(*this, 0, false,
3402                                       const_cast<Type*>(T.getTypePtr()));
3403  }
3404
3405  case NestedNameSpecifier::Global:
3406    // The global specifier is canonical and unique.
3407    return NNS;
3408  }
3409
3410  // Required to silence a GCC warning
3411  return 0;
3412}
3413
3414
3415const ArrayType *ASTContext::getAsArrayType(QualType T) const {
3416  // Handle the non-qualified case efficiently.
3417  if (!T.hasLocalQualifiers()) {
3418    // Handle the common positive case fast.
3419    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
3420      return AT;
3421  }
3422
3423  // Handle the common negative case fast.
3424  if (!isa<ArrayType>(T.getCanonicalType()))
3425    return 0;
3426
3427  // Apply any qualifiers from the array type to the element type.  This
3428  // implements C99 6.7.3p8: "If the specification of an array type includes
3429  // any type qualifiers, the element type is so qualified, not the array type."
3430
3431  // If we get here, we either have type qualifiers on the type, or we have
3432  // sugar such as a typedef in the way.  If we have type qualifiers on the type
3433  // we must propagate them down into the element type.
3434
3435  SplitQualType split = T.getSplitDesugaredType();
3436  Qualifiers qs = split.second;
3437
3438  // If we have a simple case, just return now.
3439  const ArrayType *ATy = dyn_cast<ArrayType>(split.first);
3440  if (ATy == 0 || qs.empty())
3441    return ATy;
3442
3443  // Otherwise, we have an array and we have qualifiers on it.  Push the
3444  // qualifiers into the array element type and return a new array type.
3445  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
3446
3447  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
3448    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
3449                                                CAT->getSizeModifier(),
3450                                           CAT->getIndexTypeCVRQualifiers()));
3451  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
3452    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
3453                                                  IAT->getSizeModifier(),
3454                                           IAT->getIndexTypeCVRQualifiers()));
3455
3456  if (const DependentSizedArrayType *DSAT
3457        = dyn_cast<DependentSizedArrayType>(ATy))
3458    return cast<ArrayType>(
3459                     getDependentSizedArrayType(NewEltTy,
3460                                                DSAT->getSizeExpr(),
3461                                                DSAT->getSizeModifier(),
3462                                              DSAT->getIndexTypeCVRQualifiers(),
3463                                                DSAT->getBracketsRange()));
3464
3465  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
3466  return cast<ArrayType>(getVariableArrayType(NewEltTy,
3467                                              VAT->getSizeExpr(),
3468                                              VAT->getSizeModifier(),
3469                                              VAT->getIndexTypeCVRQualifiers(),
3470                                              VAT->getBracketsRange()));
3471}
3472
3473QualType ASTContext::getAdjustedParameterType(QualType T) {
3474  // C99 6.7.5.3p7:
3475  //   A declaration of a parameter as "array of type" shall be
3476  //   adjusted to "qualified pointer to type", where the type
3477  //   qualifiers (if any) are those specified within the [ and ] of
3478  //   the array type derivation.
3479  if (T->isArrayType())
3480    return getArrayDecayedType(T);
3481
3482  // C99 6.7.5.3p8:
3483  //   A declaration of a parameter as "function returning type"
3484  //   shall be adjusted to "pointer to function returning type", as
3485  //   in 6.3.2.1.
3486  if (T->isFunctionType())
3487    return getPointerType(T);
3488
3489  return T;
3490}
3491
3492QualType ASTContext::getSignatureParameterType(QualType T) {
3493  T = getVariableArrayDecayedType(T);
3494  T = getAdjustedParameterType(T);
3495  return T.getUnqualifiedType();
3496}
3497
3498/// getArrayDecayedType - Return the properly qualified result of decaying the
3499/// specified array type to a pointer.  This operation is non-trivial when
3500/// handling typedefs etc.  The canonical type of "T" must be an array type,
3501/// this returns a pointer to a properly qualified element of the array.
3502///
3503/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
3504QualType ASTContext::getArrayDecayedType(QualType Ty) const {
3505  // Get the element type with 'getAsArrayType' so that we don't lose any
3506  // typedefs in the element type of the array.  This also handles propagation
3507  // of type qualifiers from the array type into the element type if present
3508  // (C99 6.7.3p8).
3509  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
3510  assert(PrettyArrayType && "Not an array type!");
3511
3512  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
3513
3514  // int x[restrict 4] ->  int *restrict
3515  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
3516}
3517
3518QualType ASTContext::getBaseElementType(const ArrayType *array) const {
3519  return getBaseElementType(array->getElementType());
3520}
3521
3522QualType ASTContext::getBaseElementType(QualType type) const {
3523  Qualifiers qs;
3524  while (true) {
3525    SplitQualType split = type.getSplitDesugaredType();
3526    const ArrayType *array = split.first->getAsArrayTypeUnsafe();
3527    if (!array) break;
3528
3529    type = array->getElementType();
3530    qs.addConsistentQualifiers(split.second);
3531  }
3532
3533  return getQualifiedType(type, qs);
3534}
3535
3536/// getConstantArrayElementCount - Returns number of constant array elements.
3537uint64_t
3538ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
3539  uint64_t ElementCount = 1;
3540  do {
3541    ElementCount *= CA->getSize().getZExtValue();
3542    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
3543  } while (CA);
3544  return ElementCount;
3545}
3546
3547/// getFloatingRank - Return a relative rank for floating point types.
3548/// This routine will assert if passed a built-in type that isn't a float.
3549static FloatingRank getFloatingRank(QualType T) {
3550  if (const ComplexType *CT = T->getAs<ComplexType>())
3551    return getFloatingRank(CT->getElementType());
3552
3553  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
3554  switch (T->getAs<BuiltinType>()->getKind()) {
3555  default: llvm_unreachable("getFloatingRank(): not a floating type");
3556  case BuiltinType::Half:       return HalfRank;
3557  case BuiltinType::Float:      return FloatRank;
3558  case BuiltinType::Double:     return DoubleRank;
3559  case BuiltinType::LongDouble: return LongDoubleRank;
3560  }
3561}
3562
3563/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
3564/// point or a complex type (based on typeDomain/typeSize).
3565/// 'typeDomain' is a real floating point or complex type.
3566/// 'typeSize' is a real floating point or complex type.
3567QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
3568                                                       QualType Domain) const {
3569  FloatingRank EltRank = getFloatingRank(Size);
3570  if (Domain->isComplexType()) {
3571    switch (EltRank) {
3572    case HalfRank: llvm_unreachable("Complex half is not supported");
3573    case FloatRank:      return FloatComplexTy;
3574    case DoubleRank:     return DoubleComplexTy;
3575    case LongDoubleRank: return LongDoubleComplexTy;
3576    }
3577  }
3578
3579  assert(Domain->isRealFloatingType() && "Unknown domain!");
3580  switch (EltRank) {
3581  case HalfRank: llvm_unreachable("Half ranks are not valid here");
3582  case FloatRank:      return FloatTy;
3583  case DoubleRank:     return DoubleTy;
3584  case LongDoubleRank: return LongDoubleTy;
3585  }
3586  llvm_unreachable("getFloatingRank(): illegal value for rank");
3587}
3588
3589/// getFloatingTypeOrder - Compare the rank of the two specified floating
3590/// point types, ignoring the domain of the type (i.e. 'double' ==
3591/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3592/// LHS < RHS, return -1.
3593int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
3594  FloatingRank LHSR = getFloatingRank(LHS);
3595  FloatingRank RHSR = getFloatingRank(RHS);
3596
3597  if (LHSR == RHSR)
3598    return 0;
3599  if (LHSR > RHSR)
3600    return 1;
3601  return -1;
3602}
3603
3604/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
3605/// routine will assert if passed a built-in type that isn't an integer or enum,
3606/// or if it is not canonicalized.
3607unsigned ASTContext::getIntegerRank(const Type *T) const {
3608  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
3609
3610  switch (cast<BuiltinType>(T)->getKind()) {
3611  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
3612  case BuiltinType::Bool:
3613    return 1 + (getIntWidth(BoolTy) << 3);
3614  case BuiltinType::Char_S:
3615  case BuiltinType::Char_U:
3616  case BuiltinType::SChar:
3617  case BuiltinType::UChar:
3618    return 2 + (getIntWidth(CharTy) << 3);
3619  case BuiltinType::Short:
3620  case BuiltinType::UShort:
3621    return 3 + (getIntWidth(ShortTy) << 3);
3622  case BuiltinType::Int:
3623  case BuiltinType::UInt:
3624    return 4 + (getIntWidth(IntTy) << 3);
3625  case BuiltinType::Long:
3626  case BuiltinType::ULong:
3627    return 5 + (getIntWidth(LongTy) << 3);
3628  case BuiltinType::LongLong:
3629  case BuiltinType::ULongLong:
3630    return 6 + (getIntWidth(LongLongTy) << 3);
3631  case BuiltinType::Int128:
3632  case BuiltinType::UInt128:
3633    return 7 + (getIntWidth(Int128Ty) << 3);
3634  }
3635}
3636
3637/// \brief Whether this is a promotable bitfield reference according
3638/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
3639///
3640/// \returns the type this bit-field will promote to, or NULL if no
3641/// promotion occurs.
3642QualType ASTContext::isPromotableBitField(Expr *E) const {
3643  if (E->isTypeDependent() || E->isValueDependent())
3644    return QualType();
3645
3646  FieldDecl *Field = E->getBitField();
3647  if (!Field)
3648    return QualType();
3649
3650  QualType FT = Field->getType();
3651
3652  uint64_t BitWidth = Field->getBitWidthValue(*this);
3653  uint64_t IntSize = getTypeSize(IntTy);
3654  // GCC extension compatibility: if the bit-field size is less than or equal
3655  // to the size of int, it gets promoted no matter what its type is.
3656  // For instance, unsigned long bf : 4 gets promoted to signed int.
3657  if (BitWidth < IntSize)
3658    return IntTy;
3659
3660  if (BitWidth == IntSize)
3661    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
3662
3663  // Types bigger than int are not subject to promotions, and therefore act
3664  // like the base type.
3665  // FIXME: This doesn't quite match what gcc does, but what gcc does here
3666  // is ridiculous.
3667  return QualType();
3668}
3669
3670/// getPromotedIntegerType - Returns the type that Promotable will
3671/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
3672/// integer type.
3673QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
3674  assert(!Promotable.isNull());
3675  assert(Promotable->isPromotableIntegerType());
3676  if (const EnumType *ET = Promotable->getAs<EnumType>())
3677    return ET->getDecl()->getPromotionType();
3678
3679  if (const BuiltinType *BT = Promotable->getAs<BuiltinType>()) {
3680    // C++ [conv.prom]: A prvalue of type char16_t, char32_t, or wchar_t
3681    // (3.9.1) can be converted to a prvalue of the first of the following
3682    // types that can represent all the values of its underlying type:
3683    // int, unsigned int, long int, unsigned long int, long long int, or
3684    // unsigned long long int [...]
3685    // FIXME: Is there some better way to compute this?
3686    if (BT->getKind() == BuiltinType::WChar_S ||
3687        BT->getKind() == BuiltinType::WChar_U ||
3688        BT->getKind() == BuiltinType::Char16 ||
3689        BT->getKind() == BuiltinType::Char32) {
3690      bool FromIsSigned = BT->getKind() == BuiltinType::WChar_S;
3691      uint64_t FromSize = getTypeSize(BT);
3692      QualType PromoteTypes[] = { IntTy, UnsignedIntTy, LongTy, UnsignedLongTy,
3693                                  LongLongTy, UnsignedLongLongTy };
3694      for (size_t Idx = 0; Idx < llvm::array_lengthof(PromoteTypes); ++Idx) {
3695        uint64_t ToSize = getTypeSize(PromoteTypes[Idx]);
3696        if (FromSize < ToSize ||
3697            (FromSize == ToSize &&
3698             FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType()))
3699          return PromoteTypes[Idx];
3700      }
3701      llvm_unreachable("char type should fit into long long");
3702    }
3703  }
3704
3705  // At this point, we should have a signed or unsigned integer type.
3706  if (Promotable->isSignedIntegerType())
3707    return IntTy;
3708  uint64_t PromotableSize = getTypeSize(Promotable);
3709  uint64_t IntSize = getTypeSize(IntTy);
3710  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3711  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3712}
3713
3714/// \brief Recurses in pointer/array types until it finds an objc retainable
3715/// type and returns its ownership.
3716Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
3717  while (!T.isNull()) {
3718    if (T.getObjCLifetime() != Qualifiers::OCL_None)
3719      return T.getObjCLifetime();
3720    if (T->isArrayType())
3721      T = getBaseElementType(T);
3722    else if (const PointerType *PT = T->getAs<PointerType>())
3723      T = PT->getPointeeType();
3724    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3725      T = RT->getPointeeType();
3726    else
3727      break;
3728  }
3729
3730  return Qualifiers::OCL_None;
3731}
3732
3733/// getIntegerTypeOrder - Returns the highest ranked integer type:
3734/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3735/// LHS < RHS, return -1.
3736int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
3737  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
3738  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
3739  if (LHSC == RHSC) return 0;
3740
3741  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3742  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3743
3744  unsigned LHSRank = getIntegerRank(LHSC);
3745  unsigned RHSRank = getIntegerRank(RHSC);
3746
3747  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3748    if (LHSRank == RHSRank) return 0;
3749    return LHSRank > RHSRank ? 1 : -1;
3750  }
3751
3752  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3753  if (LHSUnsigned) {
3754    // If the unsigned [LHS] type is larger, return it.
3755    if (LHSRank >= RHSRank)
3756      return 1;
3757
3758    // If the signed type can represent all values of the unsigned type, it
3759    // wins.  Because we are dealing with 2's complement and types that are
3760    // powers of two larger than each other, this is always safe.
3761    return -1;
3762  }
3763
3764  // If the unsigned [RHS] type is larger, return it.
3765  if (RHSRank >= LHSRank)
3766    return -1;
3767
3768  // If the signed type can represent all values of the unsigned type, it
3769  // wins.  Because we are dealing with 2's complement and types that are
3770  // powers of two larger than each other, this is always safe.
3771  return 1;
3772}
3773
3774static RecordDecl *
3775CreateRecordDecl(const ASTContext &Ctx, RecordDecl::TagKind TK,
3776                 DeclContext *DC, IdentifierInfo *Id) {
3777  SourceLocation Loc;
3778  if (Ctx.getLangOptions().CPlusPlus)
3779    return CXXRecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3780  else
3781    return RecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3782}
3783
3784// getCFConstantStringType - Return the type used for constant CFStrings.
3785QualType ASTContext::getCFConstantStringType() const {
3786  if (!CFConstantStringTypeDecl) {
3787    CFConstantStringTypeDecl =
3788      CreateRecordDecl(*this, TTK_Struct, TUDecl,
3789                       &Idents.get("NSConstantString"));
3790    CFConstantStringTypeDecl->startDefinition();
3791
3792    QualType FieldTypes[4];
3793
3794    // const int *isa;
3795    FieldTypes[0] = getPointerType(IntTy.withConst());
3796    // int flags;
3797    FieldTypes[1] = IntTy;
3798    // const char *str;
3799    FieldTypes[2] = getPointerType(CharTy.withConst());
3800    // long length;
3801    FieldTypes[3] = LongTy;
3802
3803    // Create fields
3804    for (unsigned i = 0; i < 4; ++i) {
3805      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3806                                           SourceLocation(),
3807                                           SourceLocation(), 0,
3808                                           FieldTypes[i], /*TInfo=*/0,
3809                                           /*BitWidth=*/0,
3810                                           /*Mutable=*/false,
3811                                           /*HasInit=*/false);
3812      Field->setAccess(AS_public);
3813      CFConstantStringTypeDecl->addDecl(Field);
3814    }
3815
3816    CFConstantStringTypeDecl->completeDefinition();
3817  }
3818
3819  return getTagDeclType(CFConstantStringTypeDecl);
3820}
3821
3822void ASTContext::setCFConstantStringType(QualType T) {
3823  const RecordType *Rec = T->getAs<RecordType>();
3824  assert(Rec && "Invalid CFConstantStringType");
3825  CFConstantStringTypeDecl = Rec->getDecl();
3826}
3827
3828QualType ASTContext::getBlockDescriptorType() const {
3829  if (BlockDescriptorType)
3830    return getTagDeclType(BlockDescriptorType);
3831
3832  RecordDecl *T;
3833  // FIXME: Needs the FlagAppleBlock bit.
3834  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3835                       &Idents.get("__block_descriptor"));
3836  T->startDefinition();
3837
3838  QualType FieldTypes[] = {
3839    UnsignedLongTy,
3840    UnsignedLongTy,
3841  };
3842
3843  const char *FieldNames[] = {
3844    "reserved",
3845    "Size"
3846  };
3847
3848  for (size_t i = 0; i < 2; ++i) {
3849    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3850                                         SourceLocation(),
3851                                         &Idents.get(FieldNames[i]),
3852                                         FieldTypes[i], /*TInfo=*/0,
3853                                         /*BitWidth=*/0,
3854                                         /*Mutable=*/false,
3855                                         /*HasInit=*/false);
3856    Field->setAccess(AS_public);
3857    T->addDecl(Field);
3858  }
3859
3860  T->completeDefinition();
3861
3862  BlockDescriptorType = T;
3863
3864  return getTagDeclType(BlockDescriptorType);
3865}
3866
3867QualType ASTContext::getBlockDescriptorExtendedType() const {
3868  if (BlockDescriptorExtendedType)
3869    return getTagDeclType(BlockDescriptorExtendedType);
3870
3871  RecordDecl *T;
3872  // FIXME: Needs the FlagAppleBlock bit.
3873  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3874                       &Idents.get("__block_descriptor_withcopydispose"));
3875  T->startDefinition();
3876
3877  QualType FieldTypes[] = {
3878    UnsignedLongTy,
3879    UnsignedLongTy,
3880    getPointerType(VoidPtrTy),
3881    getPointerType(VoidPtrTy)
3882  };
3883
3884  const char *FieldNames[] = {
3885    "reserved",
3886    "Size",
3887    "CopyFuncPtr",
3888    "DestroyFuncPtr"
3889  };
3890
3891  for (size_t i = 0; i < 4; ++i) {
3892    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3893                                         SourceLocation(),
3894                                         &Idents.get(FieldNames[i]),
3895                                         FieldTypes[i], /*TInfo=*/0,
3896                                         /*BitWidth=*/0,
3897                                         /*Mutable=*/false,
3898                                         /*HasInit=*/false);
3899    Field->setAccess(AS_public);
3900    T->addDecl(Field);
3901  }
3902
3903  T->completeDefinition();
3904
3905  BlockDescriptorExtendedType = T;
3906
3907  return getTagDeclType(BlockDescriptorExtendedType);
3908}
3909
3910bool ASTContext::BlockRequiresCopying(QualType Ty) const {
3911  if (Ty->isObjCRetainableType())
3912    return true;
3913  if (getLangOptions().CPlusPlus) {
3914    if (const RecordType *RT = Ty->getAs<RecordType>()) {
3915      CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
3916      return RD->hasConstCopyConstructor();
3917
3918    }
3919  }
3920  return false;
3921}
3922
3923QualType
3924ASTContext::BuildByRefType(StringRef DeclName, QualType Ty) const {
3925  //  type = struct __Block_byref_1_X {
3926  //    void *__isa;
3927  //    struct __Block_byref_1_X *__forwarding;
3928  //    unsigned int __flags;
3929  //    unsigned int __size;
3930  //    void *__copy_helper;            // as needed
3931  //    void *__destroy_help            // as needed
3932  //    int X;
3933  //  } *
3934
3935  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3936
3937  // FIXME: Move up
3938  llvm::SmallString<36> Name;
3939  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3940                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3941  RecordDecl *T;
3942  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, &Idents.get(Name.str()));
3943  T->startDefinition();
3944  QualType Int32Ty = IntTy;
3945  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3946  QualType FieldTypes[] = {
3947    getPointerType(VoidPtrTy),
3948    getPointerType(getTagDeclType(T)),
3949    Int32Ty,
3950    Int32Ty,
3951    getPointerType(VoidPtrTy),
3952    getPointerType(VoidPtrTy),
3953    Ty
3954  };
3955
3956  StringRef FieldNames[] = {
3957    "__isa",
3958    "__forwarding",
3959    "__flags",
3960    "__size",
3961    "__copy_helper",
3962    "__destroy_helper",
3963    DeclName,
3964  };
3965
3966  for (size_t i = 0; i < 7; ++i) {
3967    if (!HasCopyAndDispose && i >=4 && i <= 5)
3968      continue;
3969    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3970                                         SourceLocation(),
3971                                         &Idents.get(FieldNames[i]),
3972                                         FieldTypes[i], /*TInfo=*/0,
3973                                         /*BitWidth=*/0, /*Mutable=*/false,
3974                                         /*HasInit=*/false);
3975    Field->setAccess(AS_public);
3976    T->addDecl(Field);
3977  }
3978
3979  T->completeDefinition();
3980
3981  return getPointerType(getTagDeclType(T));
3982}
3983
3984TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
3985  if (!ObjCInstanceTypeDecl)
3986    ObjCInstanceTypeDecl = TypedefDecl::Create(*this,
3987                                               getTranslationUnitDecl(),
3988                                               SourceLocation(),
3989                                               SourceLocation(),
3990                                               &Idents.get("instancetype"),
3991                                     getTrivialTypeSourceInfo(getObjCIdType()));
3992  return ObjCInstanceTypeDecl;
3993}
3994
3995// This returns true if a type has been typedefed to BOOL:
3996// typedef <type> BOOL;
3997static bool isTypeTypedefedAsBOOL(QualType T) {
3998  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3999    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
4000      return II->isStr("BOOL");
4001
4002  return false;
4003}
4004
4005/// getObjCEncodingTypeSize returns size of type for objective-c encoding
4006/// purpose.
4007CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
4008  if (!type->isIncompleteArrayType() && type->isIncompleteType())
4009    return CharUnits::Zero();
4010
4011  CharUnits sz = getTypeSizeInChars(type);
4012
4013  // Make all integer and enum types at least as large as an int
4014  if (sz.isPositive() && type->isIntegralOrEnumerationType())
4015    sz = std::max(sz, getTypeSizeInChars(IntTy));
4016  // Treat arrays as pointers, since that's how they're passed in.
4017  else if (type->isArrayType())
4018    sz = getTypeSizeInChars(VoidPtrTy);
4019  return sz;
4020}
4021
4022static inline
4023std::string charUnitsToString(const CharUnits &CU) {
4024  return llvm::itostr(CU.getQuantity());
4025}
4026
4027/// getObjCEncodingForBlock - Return the encoded type for this block
4028/// declaration.
4029std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
4030  std::string S;
4031
4032  const BlockDecl *Decl = Expr->getBlockDecl();
4033  QualType BlockTy =
4034      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
4035  // Encode result type.
4036  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
4037  // Compute size of all parameters.
4038  // Start with computing size of a pointer in number of bytes.
4039  // FIXME: There might(should) be a better way of doing this computation!
4040  SourceLocation Loc;
4041  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4042  CharUnits ParmOffset = PtrSize;
4043  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
4044       E = Decl->param_end(); PI != E; ++PI) {
4045    QualType PType = (*PI)->getType();
4046    CharUnits sz = getObjCEncodingTypeSize(PType);
4047    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
4048    ParmOffset += sz;
4049  }
4050  // Size of the argument frame
4051  S += charUnitsToString(ParmOffset);
4052  // Block pointer and offset.
4053  S += "@?0";
4054
4055  // Argument types.
4056  ParmOffset = PtrSize;
4057  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
4058       Decl->param_end(); PI != E; ++PI) {
4059    ParmVarDecl *PVDecl = *PI;
4060    QualType PType = PVDecl->getOriginalType();
4061    if (const ArrayType *AT =
4062          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4063      // Use array's original type only if it has known number of
4064      // elements.
4065      if (!isa<ConstantArrayType>(AT))
4066        PType = PVDecl->getType();
4067    } else if (PType->isFunctionType())
4068      PType = PVDecl->getType();
4069    getObjCEncodingForType(PType, S);
4070    S += charUnitsToString(ParmOffset);
4071    ParmOffset += getObjCEncodingTypeSize(PType);
4072  }
4073
4074  return S;
4075}
4076
4077bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
4078                                                std::string& S) {
4079  // Encode result type.
4080  getObjCEncodingForType(Decl->getResultType(), S);
4081  CharUnits ParmOffset;
4082  // Compute size of all parameters.
4083  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4084       E = Decl->param_end(); PI != E; ++PI) {
4085    QualType PType = (*PI)->getType();
4086    CharUnits sz = getObjCEncodingTypeSize(PType);
4087    if (sz.isZero())
4088      return true;
4089
4090    assert (sz.isPositive() &&
4091        "getObjCEncodingForFunctionDecl - Incomplete param type");
4092    ParmOffset += sz;
4093  }
4094  S += charUnitsToString(ParmOffset);
4095  ParmOffset = CharUnits::Zero();
4096
4097  // Argument types.
4098  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4099       E = Decl->param_end(); PI != E; ++PI) {
4100    ParmVarDecl *PVDecl = *PI;
4101    QualType PType = PVDecl->getOriginalType();
4102    if (const ArrayType *AT =
4103          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4104      // Use array's original type only if it has known number of
4105      // elements.
4106      if (!isa<ConstantArrayType>(AT))
4107        PType = PVDecl->getType();
4108    } else if (PType->isFunctionType())
4109      PType = PVDecl->getType();
4110    getObjCEncodingForType(PType, S);
4111    S += charUnitsToString(ParmOffset);
4112    ParmOffset += getObjCEncodingTypeSize(PType);
4113  }
4114
4115  return false;
4116}
4117
4118/// getObjCEncodingForMethodParameter - Return the encoded type for a single
4119/// method parameter or return type. If Extended, include class names and
4120/// block object types.
4121void ASTContext::getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
4122                                                   QualType T, std::string& S,
4123                                                   bool Extended) const {
4124  // Encode type qualifer, 'in', 'inout', etc. for the parameter.
4125  getObjCEncodingForTypeQualifier(QT, S);
4126  // Encode parameter type.
4127  getObjCEncodingForTypeImpl(T, S, true, true, 0,
4128                             true     /*OutermostType*/,
4129                             false    /*EncodingProperty*/,
4130                             false    /*StructField*/,
4131                             Extended /*EncodeBlockParameters*/,
4132                             Extended /*EncodeClassNames*/);
4133}
4134
4135/// getObjCEncodingForMethodDecl - Return the encoded type for this method
4136/// declaration.
4137bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
4138                                              std::string& S,
4139                                              bool Extended) const {
4140  // FIXME: This is not very efficient.
4141  // Encode return type.
4142  getObjCEncodingForMethodParameter(Decl->getObjCDeclQualifier(),
4143                                    Decl->getResultType(), S, Extended);
4144  // Compute size of all parameters.
4145  // Start with computing size of a pointer in number of bytes.
4146  // FIXME: There might(should) be a better way of doing this computation!
4147  SourceLocation Loc;
4148  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4149  // The first two arguments (self and _cmd) are pointers; account for
4150  // their size.
4151  CharUnits ParmOffset = 2 * PtrSize;
4152  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4153       E = Decl->sel_param_end(); PI != E; ++PI) {
4154    QualType PType = (*PI)->getType();
4155    CharUnits sz = getObjCEncodingTypeSize(PType);
4156    if (sz.isZero())
4157      return true;
4158
4159    assert (sz.isPositive() &&
4160        "getObjCEncodingForMethodDecl - Incomplete param type");
4161    ParmOffset += sz;
4162  }
4163  S += charUnitsToString(ParmOffset);
4164  S += "@0:";
4165  S += charUnitsToString(PtrSize);
4166
4167  // Argument types.
4168  ParmOffset = 2 * PtrSize;
4169  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4170       E = Decl->sel_param_end(); PI != E; ++PI) {
4171    const ParmVarDecl *PVDecl = *PI;
4172    QualType PType = PVDecl->getOriginalType();
4173    if (const ArrayType *AT =
4174          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4175      // Use array's original type only if it has known number of
4176      // elements.
4177      if (!isa<ConstantArrayType>(AT))
4178        PType = PVDecl->getType();
4179    } else if (PType->isFunctionType())
4180      PType = PVDecl->getType();
4181    getObjCEncodingForMethodParameter(PVDecl->getObjCDeclQualifier(),
4182                                      PType, S, Extended);
4183    S += charUnitsToString(ParmOffset);
4184    ParmOffset += getObjCEncodingTypeSize(PType);
4185  }
4186
4187  return false;
4188}
4189
4190/// getObjCEncodingForPropertyDecl - Return the encoded type for this
4191/// property declaration. If non-NULL, Container must be either an
4192/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
4193/// NULL when getting encodings for protocol properties.
4194/// Property attributes are stored as a comma-delimited C string. The simple
4195/// attributes readonly and bycopy are encoded as single characters. The
4196/// parametrized attributes, getter=name, setter=name, and ivar=name, are
4197/// encoded as single characters, followed by an identifier. Property types
4198/// are also encoded as a parametrized attribute. The characters used to encode
4199/// these attributes are defined by the following enumeration:
4200/// @code
4201/// enum PropertyAttributes {
4202/// kPropertyReadOnly = 'R',   // property is read-only.
4203/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
4204/// kPropertyByref = '&',  // property is a reference to the value last assigned
4205/// kPropertyDynamic = 'D',    // property is dynamic
4206/// kPropertyGetter = 'G',     // followed by getter selector name
4207/// kPropertySetter = 'S',     // followed by setter selector name
4208/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
4209/// kPropertyType = 't'              // followed by old-style type encoding.
4210/// kPropertyWeak = 'W'              // 'weak' property
4211/// kPropertyStrong = 'P'            // property GC'able
4212/// kPropertyNonAtomic = 'N'         // property non-atomic
4213/// };
4214/// @endcode
4215void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
4216                                                const Decl *Container,
4217                                                std::string& S) const {
4218  // Collect information from the property implementation decl(s).
4219  bool Dynamic = false;
4220  ObjCPropertyImplDecl *SynthesizePID = 0;
4221
4222  // FIXME: Duplicated code due to poor abstraction.
4223  if (Container) {
4224    if (const ObjCCategoryImplDecl *CID =
4225        dyn_cast<ObjCCategoryImplDecl>(Container)) {
4226      for (ObjCCategoryImplDecl::propimpl_iterator
4227             i = CID->propimpl_begin(), e = CID->propimpl_end();
4228           i != e; ++i) {
4229        ObjCPropertyImplDecl *PID = *i;
4230        if (PID->getPropertyDecl() == PD) {
4231          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4232            Dynamic = true;
4233          } else {
4234            SynthesizePID = PID;
4235          }
4236        }
4237      }
4238    } else {
4239      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
4240      for (ObjCCategoryImplDecl::propimpl_iterator
4241             i = OID->propimpl_begin(), e = OID->propimpl_end();
4242           i != e; ++i) {
4243        ObjCPropertyImplDecl *PID = *i;
4244        if (PID->getPropertyDecl() == PD) {
4245          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4246            Dynamic = true;
4247          } else {
4248            SynthesizePID = PID;
4249          }
4250        }
4251      }
4252    }
4253  }
4254
4255  // FIXME: This is not very efficient.
4256  S = "T";
4257
4258  // Encode result type.
4259  // GCC has some special rules regarding encoding of properties which
4260  // closely resembles encoding of ivars.
4261  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
4262                             true /* outermost type */,
4263                             true /* encoding for property */);
4264
4265  if (PD->isReadOnly()) {
4266    S += ",R";
4267  } else {
4268    switch (PD->getSetterKind()) {
4269    case ObjCPropertyDecl::Assign: break;
4270    case ObjCPropertyDecl::Copy:   S += ",C"; break;
4271    case ObjCPropertyDecl::Retain: S += ",&"; break;
4272    case ObjCPropertyDecl::Weak:   S += ",W"; break;
4273    }
4274  }
4275
4276  // It really isn't clear at all what this means, since properties
4277  // are "dynamic by default".
4278  if (Dynamic)
4279    S += ",D";
4280
4281  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
4282    S += ",N";
4283
4284  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
4285    S += ",G";
4286    S += PD->getGetterName().getAsString();
4287  }
4288
4289  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
4290    S += ",S";
4291    S += PD->getSetterName().getAsString();
4292  }
4293
4294  if (SynthesizePID) {
4295    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
4296    S += ",V";
4297    S += OID->getNameAsString();
4298  }
4299
4300  // FIXME: OBJCGC: weak & strong
4301}
4302
4303/// getLegacyIntegralTypeEncoding -
4304/// Another legacy compatibility encoding: 32-bit longs are encoded as
4305/// 'l' or 'L' , but not always.  For typedefs, we need to use
4306/// 'i' or 'I' instead if encoding a struct field, or a pointer!
4307///
4308void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
4309  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
4310    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
4311      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
4312        PointeeTy = UnsignedIntTy;
4313      else
4314        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
4315          PointeeTy = IntTy;
4316    }
4317  }
4318}
4319
4320void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
4321                                        const FieldDecl *Field) const {
4322  // We follow the behavior of gcc, expanding structures which are
4323  // directly pointed to, and expanding embedded structures. Note that
4324  // these rules are sufficient to prevent recursive encoding of the
4325  // same type.
4326  getObjCEncodingForTypeImpl(T, S, true, true, Field,
4327                             true /* outermost type */);
4328}
4329
4330static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
4331    switch (T->getAs<BuiltinType>()->getKind()) {
4332    default: llvm_unreachable("Unhandled builtin type kind");
4333    case BuiltinType::Void:       return 'v';
4334    case BuiltinType::Bool:       return 'B';
4335    case BuiltinType::Char_U:
4336    case BuiltinType::UChar:      return 'C';
4337    case BuiltinType::UShort:     return 'S';
4338    case BuiltinType::UInt:       return 'I';
4339    case BuiltinType::ULong:
4340        return C->getIntWidth(T) == 32 ? 'L' : 'Q';
4341    case BuiltinType::UInt128:    return 'T';
4342    case BuiltinType::ULongLong:  return 'Q';
4343    case BuiltinType::Char_S:
4344    case BuiltinType::SChar:      return 'c';
4345    case BuiltinType::Short:      return 's';
4346    case BuiltinType::WChar_S:
4347    case BuiltinType::WChar_U:
4348    case BuiltinType::Int:        return 'i';
4349    case BuiltinType::Long:
4350      return C->getIntWidth(T) == 32 ? 'l' : 'q';
4351    case BuiltinType::LongLong:   return 'q';
4352    case BuiltinType::Int128:     return 't';
4353    case BuiltinType::Float:      return 'f';
4354    case BuiltinType::Double:     return 'd';
4355    case BuiltinType::LongDouble: return 'D';
4356    }
4357}
4358
4359static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
4360  EnumDecl *Enum = ET->getDecl();
4361
4362  // The encoding of an non-fixed enum type is always 'i', regardless of size.
4363  if (!Enum->isFixed())
4364    return 'i';
4365
4366  // The encoding of a fixed enum type matches its fixed underlying type.
4367  return ObjCEncodingForPrimitiveKind(C, Enum->getIntegerType());
4368}
4369
4370static void EncodeBitField(const ASTContext *Ctx, std::string& S,
4371                           QualType T, const FieldDecl *FD) {
4372  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
4373  S += 'b';
4374  // The NeXT runtime encodes bit fields as b followed by the number of bits.
4375  // The GNU runtime requires more information; bitfields are encoded as b,
4376  // then the offset (in bits) of the first element, then the type of the
4377  // bitfield, then the size in bits.  For example, in this structure:
4378  //
4379  // struct
4380  // {
4381  //    int integer;
4382  //    int flags:2;
4383  // };
4384  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
4385  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
4386  // information is not especially sensible, but we're stuck with it for
4387  // compatibility with GCC, although providing it breaks anything that
4388  // actually uses runtime introspection and wants to work on both runtimes...
4389  if (!Ctx->getLangOptions().NeXTRuntime) {
4390    const RecordDecl *RD = FD->getParent();
4391    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
4392    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
4393    if (const EnumType *ET = T->getAs<EnumType>())
4394      S += ObjCEncodingForEnumType(Ctx, ET);
4395    else
4396      S += ObjCEncodingForPrimitiveKind(Ctx, T);
4397  }
4398  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
4399}
4400
4401// FIXME: Use SmallString for accumulating string.
4402void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
4403                                            bool ExpandPointedToStructures,
4404                                            bool ExpandStructures,
4405                                            const FieldDecl *FD,
4406                                            bool OutermostType,
4407                                            bool EncodingProperty,
4408                                            bool StructField,
4409                                            bool EncodeBlockParameters,
4410                                            bool EncodeClassNames) const {
4411  if (T->getAs<BuiltinType>()) {
4412    if (FD && FD->isBitField())
4413      return EncodeBitField(this, S, T, FD);
4414    S += ObjCEncodingForPrimitiveKind(this, T);
4415    return;
4416  }
4417
4418  if (const ComplexType *CT = T->getAs<ComplexType>()) {
4419    S += 'j';
4420    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
4421                               false);
4422    return;
4423  }
4424
4425  // encoding for pointer or r3eference types.
4426  QualType PointeeTy;
4427  if (const PointerType *PT = T->getAs<PointerType>()) {
4428    if (PT->isObjCSelType()) {
4429      S += ':';
4430      return;
4431    }
4432    PointeeTy = PT->getPointeeType();
4433  }
4434  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4435    PointeeTy = RT->getPointeeType();
4436  if (!PointeeTy.isNull()) {
4437    bool isReadOnly = false;
4438    // For historical/compatibility reasons, the read-only qualifier of the
4439    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
4440    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
4441    // Also, do not emit the 'r' for anything but the outermost type!
4442    if (isa<TypedefType>(T.getTypePtr())) {
4443      if (OutermostType && T.isConstQualified()) {
4444        isReadOnly = true;
4445        S += 'r';
4446      }
4447    } else if (OutermostType) {
4448      QualType P = PointeeTy;
4449      while (P->getAs<PointerType>())
4450        P = P->getAs<PointerType>()->getPointeeType();
4451      if (P.isConstQualified()) {
4452        isReadOnly = true;
4453        S += 'r';
4454      }
4455    }
4456    if (isReadOnly) {
4457      // Another legacy compatibility encoding. Some ObjC qualifier and type
4458      // combinations need to be rearranged.
4459      // Rewrite "in const" from "nr" to "rn"
4460      if (StringRef(S).endswith("nr"))
4461        S.replace(S.end()-2, S.end(), "rn");
4462    }
4463
4464    if (PointeeTy->isCharType()) {
4465      // char pointer types should be encoded as '*' unless it is a
4466      // type that has been typedef'd to 'BOOL'.
4467      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
4468        S += '*';
4469        return;
4470      }
4471    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
4472      // GCC binary compat: Need to convert "struct objc_class *" to "#".
4473      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
4474        S += '#';
4475        return;
4476      }
4477      // GCC binary compat: Need to convert "struct objc_object *" to "@".
4478      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
4479        S += '@';
4480        return;
4481      }
4482      // fall through...
4483    }
4484    S += '^';
4485    getLegacyIntegralTypeEncoding(PointeeTy);
4486
4487    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
4488                               NULL);
4489    return;
4490  }
4491
4492  if (const ArrayType *AT =
4493      // Ignore type qualifiers etc.
4494        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
4495    if (isa<IncompleteArrayType>(AT) && !StructField) {
4496      // Incomplete arrays are encoded as a pointer to the array element.
4497      S += '^';
4498
4499      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4500                                 false, ExpandStructures, FD);
4501    } else {
4502      S += '[';
4503
4504      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
4505        if (getTypeSize(CAT->getElementType()) == 0)
4506          S += '0';
4507        else
4508          S += llvm::utostr(CAT->getSize().getZExtValue());
4509      } else {
4510        //Variable length arrays are encoded as a regular array with 0 elements.
4511        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
4512               "Unknown array type!");
4513        S += '0';
4514      }
4515
4516      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4517                                 false, ExpandStructures, FD);
4518      S += ']';
4519    }
4520    return;
4521  }
4522
4523  if (T->getAs<FunctionType>()) {
4524    S += '?';
4525    return;
4526  }
4527
4528  if (const RecordType *RTy = T->getAs<RecordType>()) {
4529    RecordDecl *RDecl = RTy->getDecl();
4530    S += RDecl->isUnion() ? '(' : '{';
4531    // Anonymous structures print as '?'
4532    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
4533      S += II->getName();
4534      if (ClassTemplateSpecializationDecl *Spec
4535          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
4536        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
4537        std::string TemplateArgsStr
4538          = TemplateSpecializationType::PrintTemplateArgumentList(
4539                                            TemplateArgs.data(),
4540                                            TemplateArgs.size(),
4541                                            (*this).getPrintingPolicy());
4542
4543        S += TemplateArgsStr;
4544      }
4545    } else {
4546      S += '?';
4547    }
4548    if (ExpandStructures) {
4549      S += '=';
4550      if (!RDecl->isUnion()) {
4551        getObjCEncodingForStructureImpl(RDecl, S, FD);
4552      } else {
4553        for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4554                                     FieldEnd = RDecl->field_end();
4555             Field != FieldEnd; ++Field) {
4556          if (FD) {
4557            S += '"';
4558            S += Field->getNameAsString();
4559            S += '"';
4560          }
4561
4562          // Special case bit-fields.
4563          if (Field->isBitField()) {
4564            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
4565                                       (*Field));
4566          } else {
4567            QualType qt = Field->getType();
4568            getLegacyIntegralTypeEncoding(qt);
4569            getObjCEncodingForTypeImpl(qt, S, false, true,
4570                                       FD, /*OutermostType*/false,
4571                                       /*EncodingProperty*/false,
4572                                       /*StructField*/true);
4573          }
4574        }
4575      }
4576    }
4577    S += RDecl->isUnion() ? ')' : '}';
4578    return;
4579  }
4580
4581  if (const EnumType *ET = T->getAs<EnumType>()) {
4582    if (FD && FD->isBitField())
4583      EncodeBitField(this, S, T, FD);
4584    else
4585      S += ObjCEncodingForEnumType(this, ET);
4586    return;
4587  }
4588
4589  if (const BlockPointerType *BT = T->getAs<BlockPointerType>()) {
4590    S += "@?"; // Unlike a pointer-to-function, which is "^?".
4591    if (EncodeBlockParameters) {
4592      const FunctionType *FT = BT->getPointeeType()->getAs<FunctionType>();
4593
4594      S += '<';
4595      // Block return type
4596      getObjCEncodingForTypeImpl(FT->getResultType(), S,
4597                                 ExpandPointedToStructures, ExpandStructures,
4598                                 FD,
4599                                 false /* OutermostType */,
4600                                 EncodingProperty,
4601                                 false /* StructField */,
4602                                 EncodeBlockParameters,
4603                                 EncodeClassNames);
4604      // Block self
4605      S += "@?";
4606      // Block parameters
4607      if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT)) {
4608        for (FunctionProtoType::arg_type_iterator I = FPT->arg_type_begin(),
4609               E = FPT->arg_type_end(); I && (I != E); ++I) {
4610          getObjCEncodingForTypeImpl(*I, S,
4611                                     ExpandPointedToStructures,
4612                                     ExpandStructures,
4613                                     FD,
4614                                     false /* OutermostType */,
4615                                     EncodingProperty,
4616                                     false /* StructField */,
4617                                     EncodeBlockParameters,
4618                                     EncodeClassNames);
4619        }
4620      }
4621      S += '>';
4622    }
4623    return;
4624  }
4625
4626  // Ignore protocol qualifiers when mangling at this level.
4627  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
4628    T = OT->getBaseType();
4629
4630  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
4631    // @encode(class_name)
4632    ObjCInterfaceDecl *OI = OIT->getDecl();
4633    S += '{';
4634    const IdentifierInfo *II = OI->getIdentifier();
4635    S += II->getName();
4636    S += '=';
4637    SmallVector<const ObjCIvarDecl*, 32> Ivars;
4638    DeepCollectObjCIvars(OI, true, Ivars);
4639    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
4640      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
4641      if (Field->isBitField())
4642        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
4643      else
4644        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
4645    }
4646    S += '}';
4647    return;
4648  }
4649
4650  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
4651    if (OPT->isObjCIdType()) {
4652      S += '@';
4653      return;
4654    }
4655
4656    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
4657      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
4658      // Since this is a binary compatibility issue, need to consult with runtime
4659      // folks. Fortunately, this is a *very* obsure construct.
4660      S += '#';
4661      return;
4662    }
4663
4664    if (OPT->isObjCQualifiedIdType()) {
4665      getObjCEncodingForTypeImpl(getObjCIdType(), S,
4666                                 ExpandPointedToStructures,
4667                                 ExpandStructures, FD);
4668      if (FD || EncodingProperty || EncodeClassNames) {
4669        // Note that we do extended encoding of protocol qualifer list
4670        // Only when doing ivar or property encoding.
4671        S += '"';
4672        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4673             E = OPT->qual_end(); I != E; ++I) {
4674          S += '<';
4675          S += (*I)->getNameAsString();
4676          S += '>';
4677        }
4678        S += '"';
4679      }
4680      return;
4681    }
4682
4683    QualType PointeeTy = OPT->getPointeeType();
4684    if (!EncodingProperty &&
4685        isa<TypedefType>(PointeeTy.getTypePtr())) {
4686      // Another historical/compatibility reason.
4687      // We encode the underlying type which comes out as
4688      // {...};
4689      S += '^';
4690      getObjCEncodingForTypeImpl(PointeeTy, S,
4691                                 false, ExpandPointedToStructures,
4692                                 NULL);
4693      return;
4694    }
4695
4696    S += '@';
4697    if (OPT->getInterfaceDecl() &&
4698        (FD || EncodingProperty || EncodeClassNames)) {
4699      S += '"';
4700      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4701      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4702           E = OPT->qual_end(); I != E; ++I) {
4703        S += '<';
4704        S += (*I)->getNameAsString();
4705        S += '>';
4706      }
4707      S += '"';
4708    }
4709    return;
4710  }
4711
4712  // gcc just blithely ignores member pointers.
4713  // TODO: maybe there should be a mangling for these
4714  if (T->getAs<MemberPointerType>())
4715    return;
4716
4717  if (T->isVectorType()) {
4718    // This matches gcc's encoding, even though technically it is
4719    // insufficient.
4720    // FIXME. We should do a better job than gcc.
4721    return;
4722  }
4723
4724  llvm_unreachable("@encode for type not implemented!");
4725}
4726
4727void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
4728                                                 std::string &S,
4729                                                 const FieldDecl *FD,
4730                                                 bool includeVBases) const {
4731  assert(RDecl && "Expected non-null RecordDecl");
4732  assert(!RDecl->isUnion() && "Should not be called for unions");
4733  if (!RDecl->getDefinition())
4734    return;
4735
4736  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
4737  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
4738  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
4739
4740  if (CXXRec) {
4741    for (CXXRecordDecl::base_class_iterator
4742           BI = CXXRec->bases_begin(),
4743           BE = CXXRec->bases_end(); BI != BE; ++BI) {
4744      if (!BI->isVirtual()) {
4745        CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4746        if (base->isEmpty())
4747          continue;
4748        uint64_t offs = layout.getBaseClassOffsetInBits(base);
4749        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4750                                  std::make_pair(offs, base));
4751      }
4752    }
4753  }
4754
4755  unsigned i = 0;
4756  for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4757                               FieldEnd = RDecl->field_end();
4758       Field != FieldEnd; ++Field, ++i) {
4759    uint64_t offs = layout.getFieldOffset(i);
4760    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4761                              std::make_pair(offs, *Field));
4762  }
4763
4764  if (CXXRec && includeVBases) {
4765    for (CXXRecordDecl::base_class_iterator
4766           BI = CXXRec->vbases_begin(),
4767           BE = CXXRec->vbases_end(); BI != BE; ++BI) {
4768      CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4769      if (base->isEmpty())
4770        continue;
4771      uint64_t offs = layout.getVBaseClassOffsetInBits(base);
4772      if (FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
4773        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
4774                                  std::make_pair(offs, base));
4775    }
4776  }
4777
4778  CharUnits size;
4779  if (CXXRec) {
4780    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
4781  } else {
4782    size = layout.getSize();
4783  }
4784
4785  uint64_t CurOffs = 0;
4786  std::multimap<uint64_t, NamedDecl *>::iterator
4787    CurLayObj = FieldOrBaseOffsets.begin();
4788
4789  if ((CurLayObj != FieldOrBaseOffsets.end() && CurLayObj->first != 0) ||
4790      (CurLayObj == FieldOrBaseOffsets.end() &&
4791         CXXRec && CXXRec->isDynamicClass())) {
4792    assert(CXXRec && CXXRec->isDynamicClass() &&
4793           "Offset 0 was empty but no VTable ?");
4794    if (FD) {
4795      S += "\"_vptr$";
4796      std::string recname = CXXRec->getNameAsString();
4797      if (recname.empty()) recname = "?";
4798      S += recname;
4799      S += '"';
4800    }
4801    S += "^^?";
4802    CurOffs += getTypeSize(VoidPtrTy);
4803  }
4804
4805  if (!RDecl->hasFlexibleArrayMember()) {
4806    // Mark the end of the structure.
4807    uint64_t offs = toBits(size);
4808    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4809                              std::make_pair(offs, (NamedDecl*)0));
4810  }
4811
4812  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
4813    assert(CurOffs <= CurLayObj->first);
4814
4815    if (CurOffs < CurLayObj->first) {
4816      uint64_t padding = CurLayObj->first - CurOffs;
4817      // FIXME: There doesn't seem to be a way to indicate in the encoding that
4818      // packing/alignment of members is different that normal, in which case
4819      // the encoding will be out-of-sync with the real layout.
4820      // If the runtime switches to just consider the size of types without
4821      // taking into account alignment, we could make padding explicit in the
4822      // encoding (e.g. using arrays of chars). The encoding strings would be
4823      // longer then though.
4824      CurOffs += padding;
4825    }
4826
4827    NamedDecl *dcl = CurLayObj->second;
4828    if (dcl == 0)
4829      break; // reached end of structure.
4830
4831    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
4832      // We expand the bases without their virtual bases since those are going
4833      // in the initial structure. Note that this differs from gcc which
4834      // expands virtual bases each time one is encountered in the hierarchy,
4835      // making the encoding type bigger than it really is.
4836      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false);
4837      assert(!base->isEmpty());
4838      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
4839    } else {
4840      FieldDecl *field = cast<FieldDecl>(dcl);
4841      if (FD) {
4842        S += '"';
4843        S += field->getNameAsString();
4844        S += '"';
4845      }
4846
4847      if (field->isBitField()) {
4848        EncodeBitField(this, S, field->getType(), field);
4849        CurOffs += field->getBitWidthValue(*this);
4850      } else {
4851        QualType qt = field->getType();
4852        getLegacyIntegralTypeEncoding(qt);
4853        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
4854                                   /*OutermostType*/false,
4855                                   /*EncodingProperty*/false,
4856                                   /*StructField*/true);
4857        CurOffs += getTypeSize(field->getType());
4858      }
4859    }
4860  }
4861}
4862
4863void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4864                                                 std::string& S) const {
4865  if (QT & Decl::OBJC_TQ_In)
4866    S += 'n';
4867  if (QT & Decl::OBJC_TQ_Inout)
4868    S += 'N';
4869  if (QT & Decl::OBJC_TQ_Out)
4870    S += 'o';
4871  if (QT & Decl::OBJC_TQ_Bycopy)
4872    S += 'O';
4873  if (QT & Decl::OBJC_TQ_Byref)
4874    S += 'R';
4875  if (QT & Decl::OBJC_TQ_Oneway)
4876    S += 'V';
4877}
4878
4879void ASTContext::setBuiltinVaListType(QualType T) {
4880  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4881
4882  BuiltinVaListType = T;
4883}
4884
4885TypedefDecl *ASTContext::getObjCIdDecl() const {
4886  if (!ObjCIdDecl) {
4887    QualType T = getObjCObjectType(ObjCBuiltinIdTy, 0, 0);
4888    T = getObjCObjectPointerType(T);
4889    TypeSourceInfo *IdInfo = getTrivialTypeSourceInfo(T);
4890    ObjCIdDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4891                                     getTranslationUnitDecl(),
4892                                     SourceLocation(), SourceLocation(),
4893                                     &Idents.get("id"), IdInfo);
4894  }
4895
4896  return ObjCIdDecl;
4897}
4898
4899TypedefDecl *ASTContext::getObjCSelDecl() const {
4900  if (!ObjCSelDecl) {
4901    QualType SelT = getPointerType(ObjCBuiltinSelTy);
4902    TypeSourceInfo *SelInfo = getTrivialTypeSourceInfo(SelT);
4903    ObjCSelDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4904                                      getTranslationUnitDecl(),
4905                                      SourceLocation(), SourceLocation(),
4906                                      &Idents.get("SEL"), SelInfo);
4907  }
4908  return ObjCSelDecl;
4909}
4910
4911void ASTContext::setObjCProtoType(QualType QT) {
4912  ObjCProtoType = QT;
4913}
4914
4915TypedefDecl *ASTContext::getObjCClassDecl() const {
4916  if (!ObjCClassDecl) {
4917    QualType T = getObjCObjectType(ObjCBuiltinClassTy, 0, 0);
4918    T = getObjCObjectPointerType(T);
4919    TypeSourceInfo *ClassInfo = getTrivialTypeSourceInfo(T);
4920    ObjCClassDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4921                                        getTranslationUnitDecl(),
4922                                        SourceLocation(), SourceLocation(),
4923                                        &Idents.get("Class"), ClassInfo);
4924  }
4925
4926  return ObjCClassDecl;
4927}
4928
4929void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4930  assert(ObjCConstantStringType.isNull() &&
4931         "'NSConstantString' type already set!");
4932
4933  ObjCConstantStringType = getObjCInterfaceType(Decl);
4934}
4935
4936/// \brief Retrieve the template name that corresponds to a non-empty
4937/// lookup.
4938TemplateName
4939ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4940                                      UnresolvedSetIterator End) const {
4941  unsigned size = End - Begin;
4942  assert(size > 1 && "set is not overloaded!");
4943
4944  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4945                          size * sizeof(FunctionTemplateDecl*));
4946  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4947
4948  NamedDecl **Storage = OT->getStorage();
4949  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4950    NamedDecl *D = *I;
4951    assert(isa<FunctionTemplateDecl>(D) ||
4952           (isa<UsingShadowDecl>(D) &&
4953            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4954    *Storage++ = D;
4955  }
4956
4957  return TemplateName(OT);
4958}
4959
4960/// \brief Retrieve the template name that represents a qualified
4961/// template name such as \c std::vector.
4962TemplateName
4963ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4964                                     bool TemplateKeyword,
4965                                     TemplateDecl *Template) const {
4966  assert(NNS && "Missing nested-name-specifier in qualified template name");
4967
4968  // FIXME: Canonicalization?
4969  llvm::FoldingSetNodeID ID;
4970  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4971
4972  void *InsertPos = 0;
4973  QualifiedTemplateName *QTN =
4974    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4975  if (!QTN) {
4976    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4977    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4978  }
4979
4980  return TemplateName(QTN);
4981}
4982
4983/// \brief Retrieve the template name that represents a dependent
4984/// template name such as \c MetaFun::template apply.
4985TemplateName
4986ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4987                                     const IdentifierInfo *Name) const {
4988  assert((!NNS || NNS->isDependent()) &&
4989         "Nested name specifier must be dependent");
4990
4991  llvm::FoldingSetNodeID ID;
4992  DependentTemplateName::Profile(ID, NNS, Name);
4993
4994  void *InsertPos = 0;
4995  DependentTemplateName *QTN =
4996    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4997
4998  if (QTN)
4999    return TemplateName(QTN);
5000
5001  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
5002  if (CanonNNS == NNS) {
5003    QTN = new (*this,4) DependentTemplateName(NNS, Name);
5004  } else {
5005    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
5006    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
5007    DependentTemplateName *CheckQTN =
5008      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5009    assert(!CheckQTN && "Dependent type name canonicalization broken");
5010    (void)CheckQTN;
5011  }
5012
5013  DependentTemplateNames.InsertNode(QTN, InsertPos);
5014  return TemplateName(QTN);
5015}
5016
5017/// \brief Retrieve the template name that represents a dependent
5018/// template name such as \c MetaFun::template operator+.
5019TemplateName
5020ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
5021                                     OverloadedOperatorKind Operator) const {
5022  assert((!NNS || NNS->isDependent()) &&
5023         "Nested name specifier must be dependent");
5024
5025  llvm::FoldingSetNodeID ID;
5026  DependentTemplateName::Profile(ID, NNS, Operator);
5027
5028  void *InsertPos = 0;
5029  DependentTemplateName *QTN
5030    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5031
5032  if (QTN)
5033    return TemplateName(QTN);
5034
5035  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
5036  if (CanonNNS == NNS) {
5037    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
5038  } else {
5039    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
5040    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
5041
5042    DependentTemplateName *CheckQTN
5043      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5044    assert(!CheckQTN && "Dependent template name canonicalization broken");
5045    (void)CheckQTN;
5046  }
5047
5048  DependentTemplateNames.InsertNode(QTN, InsertPos);
5049  return TemplateName(QTN);
5050}
5051
5052TemplateName
5053ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
5054                                         TemplateName replacement) const {
5055  llvm::FoldingSetNodeID ID;
5056  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
5057
5058  void *insertPos = 0;
5059  SubstTemplateTemplateParmStorage *subst
5060    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
5061
5062  if (!subst) {
5063    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
5064    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
5065  }
5066
5067  return TemplateName(subst);
5068}
5069
5070TemplateName
5071ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
5072                                       const TemplateArgument &ArgPack) const {
5073  ASTContext &Self = const_cast<ASTContext &>(*this);
5074  llvm::FoldingSetNodeID ID;
5075  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
5076
5077  void *InsertPos = 0;
5078  SubstTemplateTemplateParmPackStorage *Subst
5079    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
5080
5081  if (!Subst) {
5082    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
5083                                                           ArgPack.pack_size(),
5084                                                         ArgPack.pack_begin());
5085    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
5086  }
5087
5088  return TemplateName(Subst);
5089}
5090
5091/// getFromTargetType - Given one of the integer types provided by
5092/// TargetInfo, produce the corresponding type. The unsigned @p Type
5093/// is actually a value of type @c TargetInfo::IntType.
5094CanQualType ASTContext::getFromTargetType(unsigned Type) const {
5095  switch (Type) {
5096  case TargetInfo::NoInt: return CanQualType();
5097  case TargetInfo::SignedShort: return ShortTy;
5098  case TargetInfo::UnsignedShort: return UnsignedShortTy;
5099  case TargetInfo::SignedInt: return IntTy;
5100  case TargetInfo::UnsignedInt: return UnsignedIntTy;
5101  case TargetInfo::SignedLong: return LongTy;
5102  case TargetInfo::UnsignedLong: return UnsignedLongTy;
5103  case TargetInfo::SignedLongLong: return LongLongTy;
5104  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
5105  }
5106
5107  llvm_unreachable("Unhandled TargetInfo::IntType value");
5108}
5109
5110//===----------------------------------------------------------------------===//
5111//                        Type Predicates.
5112//===----------------------------------------------------------------------===//
5113
5114/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
5115/// garbage collection attribute.
5116///
5117Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
5118  if (getLangOptions().getGC() == LangOptions::NonGC)
5119    return Qualifiers::GCNone;
5120
5121  assert(getLangOptions().ObjC1);
5122  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
5123
5124  // Default behaviour under objective-C's gc is for ObjC pointers
5125  // (or pointers to them) be treated as though they were declared
5126  // as __strong.
5127  if (GCAttrs == Qualifiers::GCNone) {
5128    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
5129      return Qualifiers::Strong;
5130    else if (Ty->isPointerType())
5131      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
5132  } else {
5133    // It's not valid to set GC attributes on anything that isn't a
5134    // pointer.
5135#ifndef NDEBUG
5136    QualType CT = Ty->getCanonicalTypeInternal();
5137    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
5138      CT = AT->getElementType();
5139    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
5140#endif
5141  }
5142  return GCAttrs;
5143}
5144
5145//===----------------------------------------------------------------------===//
5146//                        Type Compatibility Testing
5147//===----------------------------------------------------------------------===//
5148
5149/// areCompatVectorTypes - Return true if the two specified vector types are
5150/// compatible.
5151static bool areCompatVectorTypes(const VectorType *LHS,
5152                                 const VectorType *RHS) {
5153  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
5154  return LHS->getElementType() == RHS->getElementType() &&
5155         LHS->getNumElements() == RHS->getNumElements();
5156}
5157
5158bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
5159                                          QualType SecondVec) {
5160  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
5161  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
5162
5163  if (hasSameUnqualifiedType(FirstVec, SecondVec))
5164    return true;
5165
5166  // Treat Neon vector types and most AltiVec vector types as if they are the
5167  // equivalent GCC vector types.
5168  const VectorType *First = FirstVec->getAs<VectorType>();
5169  const VectorType *Second = SecondVec->getAs<VectorType>();
5170  if (First->getNumElements() == Second->getNumElements() &&
5171      hasSameType(First->getElementType(), Second->getElementType()) &&
5172      First->getVectorKind() != VectorType::AltiVecPixel &&
5173      First->getVectorKind() != VectorType::AltiVecBool &&
5174      Second->getVectorKind() != VectorType::AltiVecPixel &&
5175      Second->getVectorKind() != VectorType::AltiVecBool)
5176    return true;
5177
5178  return false;
5179}
5180
5181//===----------------------------------------------------------------------===//
5182// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
5183//===----------------------------------------------------------------------===//
5184
5185/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
5186/// inheritance hierarchy of 'rProto'.
5187bool
5188ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
5189                                           ObjCProtocolDecl *rProto) const {
5190  if (declaresSameEntity(lProto, rProto))
5191    return true;
5192  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
5193       E = rProto->protocol_end(); PI != E; ++PI)
5194    if (ProtocolCompatibleWithProtocol(lProto, *PI))
5195      return true;
5196  return false;
5197}
5198
5199/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
5200/// return true if lhs's protocols conform to rhs's protocol; false
5201/// otherwise.
5202bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
5203  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
5204    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
5205  return false;
5206}
5207
5208/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
5209/// Class<p1, ...>.
5210bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
5211                                                      QualType rhs) {
5212  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
5213  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5214  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
5215
5216  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5217       E = lhsQID->qual_end(); I != E; ++I) {
5218    bool match = false;
5219    ObjCProtocolDecl *lhsProto = *I;
5220    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5221         E = rhsOPT->qual_end(); J != E; ++J) {
5222      ObjCProtocolDecl *rhsProto = *J;
5223      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
5224        match = true;
5225        break;
5226      }
5227    }
5228    if (!match)
5229      return false;
5230  }
5231  return true;
5232}
5233
5234/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
5235/// ObjCQualifiedIDType.
5236bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
5237                                                   bool compare) {
5238  // Allow id<P..> and an 'id' or void* type in all cases.
5239  if (lhs->isVoidPointerType() ||
5240      lhs->isObjCIdType() || lhs->isObjCClassType())
5241    return true;
5242  else if (rhs->isVoidPointerType() ||
5243           rhs->isObjCIdType() || rhs->isObjCClassType())
5244    return true;
5245
5246  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
5247    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5248
5249    if (!rhsOPT) return false;
5250
5251    if (rhsOPT->qual_empty()) {
5252      // If the RHS is a unqualified interface pointer "NSString*",
5253      // make sure we check the class hierarchy.
5254      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5255        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5256             E = lhsQID->qual_end(); I != E; ++I) {
5257          // when comparing an id<P> on lhs with a static type on rhs,
5258          // see if static class implements all of id's protocols, directly or
5259          // through its super class and categories.
5260          if (!rhsID->ClassImplementsProtocol(*I, true))
5261            return false;
5262        }
5263      }
5264      // If there are no qualifiers and no interface, we have an 'id'.
5265      return true;
5266    }
5267    // Both the right and left sides have qualifiers.
5268    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5269         E = lhsQID->qual_end(); I != E; ++I) {
5270      ObjCProtocolDecl *lhsProto = *I;
5271      bool match = false;
5272
5273      // when comparing an id<P> on lhs with a static type on rhs,
5274      // see if static class implements all of id's protocols, directly or
5275      // through its super class and categories.
5276      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5277           E = rhsOPT->qual_end(); J != E; ++J) {
5278        ObjCProtocolDecl *rhsProto = *J;
5279        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5280            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5281          match = true;
5282          break;
5283        }
5284      }
5285      // If the RHS is a qualified interface pointer "NSString<P>*",
5286      // make sure we check the class hierarchy.
5287      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5288        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5289             E = lhsQID->qual_end(); I != E; ++I) {
5290          // when comparing an id<P> on lhs with a static type on rhs,
5291          // see if static class implements all of id's protocols, directly or
5292          // through its super class and categories.
5293          if (rhsID->ClassImplementsProtocol(*I, true)) {
5294            match = true;
5295            break;
5296          }
5297        }
5298      }
5299      if (!match)
5300        return false;
5301    }
5302
5303    return true;
5304  }
5305
5306  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
5307  assert(rhsQID && "One of the LHS/RHS should be id<x>");
5308
5309  if (const ObjCObjectPointerType *lhsOPT =
5310        lhs->getAsObjCInterfacePointerType()) {
5311    // If both the right and left sides have qualifiers.
5312    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
5313         E = lhsOPT->qual_end(); I != E; ++I) {
5314      ObjCProtocolDecl *lhsProto = *I;
5315      bool match = false;
5316
5317      // when comparing an id<P> on rhs with a static type on lhs,
5318      // see if static class implements all of id's protocols, directly or
5319      // through its super class and categories.
5320      // First, lhs protocols in the qualifier list must be found, direct
5321      // or indirect in rhs's qualifier list or it is a mismatch.
5322      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5323           E = rhsQID->qual_end(); J != E; ++J) {
5324        ObjCProtocolDecl *rhsProto = *J;
5325        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5326            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5327          match = true;
5328          break;
5329        }
5330      }
5331      if (!match)
5332        return false;
5333    }
5334
5335    // Static class's protocols, or its super class or category protocols
5336    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
5337    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
5338      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5339      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
5340      // This is rather dubious but matches gcc's behavior. If lhs has
5341      // no type qualifier and its class has no static protocol(s)
5342      // assume that it is mismatch.
5343      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
5344        return false;
5345      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5346           LHSInheritedProtocols.begin(),
5347           E = LHSInheritedProtocols.end(); I != E; ++I) {
5348        bool match = false;
5349        ObjCProtocolDecl *lhsProto = (*I);
5350        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5351             E = rhsQID->qual_end(); J != E; ++J) {
5352          ObjCProtocolDecl *rhsProto = *J;
5353          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5354              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5355            match = true;
5356            break;
5357          }
5358        }
5359        if (!match)
5360          return false;
5361      }
5362    }
5363    return true;
5364  }
5365  return false;
5366}
5367
5368/// canAssignObjCInterfaces - Return true if the two interface types are
5369/// compatible for assignment from RHS to LHS.  This handles validation of any
5370/// protocol qualifiers on the LHS or RHS.
5371///
5372bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
5373                                         const ObjCObjectPointerType *RHSOPT) {
5374  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5375  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5376
5377  // If either type represents the built-in 'id' or 'Class' types, return true.
5378  if (LHS->isObjCUnqualifiedIdOrClass() ||
5379      RHS->isObjCUnqualifiedIdOrClass())
5380    return true;
5381
5382  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
5383    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5384                                             QualType(RHSOPT,0),
5385                                             false);
5386
5387  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
5388    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
5389                                                QualType(RHSOPT,0));
5390
5391  // If we have 2 user-defined types, fall into that path.
5392  if (LHS->getInterface() && RHS->getInterface())
5393    return canAssignObjCInterfaces(LHS, RHS);
5394
5395  return false;
5396}
5397
5398/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
5399/// for providing type-safety for objective-c pointers used to pass/return
5400/// arguments in block literals. When passed as arguments, passing 'A*' where
5401/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
5402/// not OK. For the return type, the opposite is not OK.
5403bool ASTContext::canAssignObjCInterfacesInBlockPointer(
5404                                         const ObjCObjectPointerType *LHSOPT,
5405                                         const ObjCObjectPointerType *RHSOPT,
5406                                         bool BlockReturnType) {
5407  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
5408    return true;
5409
5410  if (LHSOPT->isObjCBuiltinType()) {
5411    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
5412  }
5413
5414  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
5415    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5416                                             QualType(RHSOPT,0),
5417                                             false);
5418
5419  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
5420  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
5421  if (LHS && RHS)  { // We have 2 user-defined types.
5422    if (LHS != RHS) {
5423      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
5424        return BlockReturnType;
5425      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
5426        return !BlockReturnType;
5427    }
5428    else
5429      return true;
5430  }
5431  return false;
5432}
5433
5434/// getIntersectionOfProtocols - This routine finds the intersection of set
5435/// of protocols inherited from two distinct objective-c pointer objects.
5436/// It is used to build composite qualifier list of the composite type of
5437/// the conditional expression involving two objective-c pointer objects.
5438static
5439void getIntersectionOfProtocols(ASTContext &Context,
5440                                const ObjCObjectPointerType *LHSOPT,
5441                                const ObjCObjectPointerType *RHSOPT,
5442      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
5443
5444  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5445  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5446  assert(LHS->getInterface() && "LHS must have an interface base");
5447  assert(RHS->getInterface() && "RHS must have an interface base");
5448
5449  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
5450  unsigned LHSNumProtocols = LHS->getNumProtocols();
5451  if (LHSNumProtocols > 0)
5452    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
5453  else {
5454    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5455    Context.CollectInheritedProtocols(LHS->getInterface(),
5456                                      LHSInheritedProtocols);
5457    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
5458                                LHSInheritedProtocols.end());
5459  }
5460
5461  unsigned RHSNumProtocols = RHS->getNumProtocols();
5462  if (RHSNumProtocols > 0) {
5463    ObjCProtocolDecl **RHSProtocols =
5464      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
5465    for (unsigned i = 0; i < RHSNumProtocols; ++i)
5466      if (InheritedProtocolSet.count(RHSProtocols[i]))
5467        IntersectionOfProtocols.push_back(RHSProtocols[i]);
5468  } else {
5469    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
5470    Context.CollectInheritedProtocols(RHS->getInterface(),
5471                                      RHSInheritedProtocols);
5472    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5473         RHSInheritedProtocols.begin(),
5474         E = RHSInheritedProtocols.end(); I != E; ++I)
5475      if (InheritedProtocolSet.count((*I)))
5476        IntersectionOfProtocols.push_back((*I));
5477  }
5478}
5479
5480/// areCommonBaseCompatible - Returns common base class of the two classes if
5481/// one found. Note that this is O'2 algorithm. But it will be called as the
5482/// last type comparison in a ?-exp of ObjC pointer types before a
5483/// warning is issued. So, its invokation is extremely rare.
5484QualType ASTContext::areCommonBaseCompatible(
5485                                          const ObjCObjectPointerType *Lptr,
5486                                          const ObjCObjectPointerType *Rptr) {
5487  const ObjCObjectType *LHS = Lptr->getObjectType();
5488  const ObjCObjectType *RHS = Rptr->getObjectType();
5489  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
5490  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
5491  if (!LDecl || !RDecl || (declaresSameEntity(LDecl, RDecl)))
5492    return QualType();
5493
5494  do {
5495    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
5496    if (canAssignObjCInterfaces(LHS, RHS)) {
5497      SmallVector<ObjCProtocolDecl *, 8> Protocols;
5498      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
5499
5500      QualType Result = QualType(LHS, 0);
5501      if (!Protocols.empty())
5502        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
5503      Result = getObjCObjectPointerType(Result);
5504      return Result;
5505    }
5506  } while ((LDecl = LDecl->getSuperClass()));
5507
5508  return QualType();
5509}
5510
5511bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
5512                                         const ObjCObjectType *RHS) {
5513  assert(LHS->getInterface() && "LHS is not an interface type");
5514  assert(RHS->getInterface() && "RHS is not an interface type");
5515
5516  // Verify that the base decls are compatible: the RHS must be a subclass of
5517  // the LHS.
5518  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
5519    return false;
5520
5521  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
5522  // protocol qualified at all, then we are good.
5523  if (LHS->getNumProtocols() == 0)
5524    return true;
5525
5526  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't,
5527  // more detailed analysis is required.
5528  if (RHS->getNumProtocols() == 0) {
5529    // OK, if LHS is a superclass of RHS *and*
5530    // this superclass is assignment compatible with LHS.
5531    // false otherwise.
5532    bool IsSuperClass =
5533      LHS->getInterface()->isSuperClassOf(RHS->getInterface());
5534    if (IsSuperClass) {
5535      // OK if conversion of LHS to SuperClass results in narrowing of types
5536      // ; i.e., SuperClass may implement at least one of the protocols
5537      // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
5538      // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
5539      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
5540      CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
5541      // If super class has no protocols, it is not a match.
5542      if (SuperClassInheritedProtocols.empty())
5543        return false;
5544
5545      for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5546           LHSPE = LHS->qual_end();
5547           LHSPI != LHSPE; LHSPI++) {
5548        bool SuperImplementsProtocol = false;
5549        ObjCProtocolDecl *LHSProto = (*LHSPI);
5550
5551        for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5552             SuperClassInheritedProtocols.begin(),
5553             E = SuperClassInheritedProtocols.end(); I != E; ++I) {
5554          ObjCProtocolDecl *SuperClassProto = (*I);
5555          if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
5556            SuperImplementsProtocol = true;
5557            break;
5558          }
5559        }
5560        if (!SuperImplementsProtocol)
5561          return false;
5562      }
5563      return true;
5564    }
5565    return false;
5566  }
5567
5568  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5569                                     LHSPE = LHS->qual_end();
5570       LHSPI != LHSPE; LHSPI++) {
5571    bool RHSImplementsProtocol = false;
5572
5573    // If the RHS doesn't implement the protocol on the left, the types
5574    // are incompatible.
5575    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
5576                                       RHSPE = RHS->qual_end();
5577         RHSPI != RHSPE; RHSPI++) {
5578      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
5579        RHSImplementsProtocol = true;
5580        break;
5581      }
5582    }
5583    // FIXME: For better diagnostics, consider passing back the protocol name.
5584    if (!RHSImplementsProtocol)
5585      return false;
5586  }
5587  // The RHS implements all protocols listed on the LHS.
5588  return true;
5589}
5590
5591bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
5592  // get the "pointed to" types
5593  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
5594  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
5595
5596  if (!LHSOPT || !RHSOPT)
5597    return false;
5598
5599  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
5600         canAssignObjCInterfaces(RHSOPT, LHSOPT);
5601}
5602
5603bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
5604  return canAssignObjCInterfaces(
5605                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
5606                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
5607}
5608
5609/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
5610/// both shall have the identically qualified version of a compatible type.
5611/// C99 6.2.7p1: Two types have compatible types if their types are the
5612/// same. See 6.7.[2,3,5] for additional rules.
5613bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
5614                                    bool CompareUnqualified) {
5615  if (getLangOptions().CPlusPlus)
5616    return hasSameType(LHS, RHS);
5617
5618  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
5619}
5620
5621bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
5622  return typesAreCompatible(LHS, RHS);
5623}
5624
5625bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
5626  return !mergeTypes(LHS, RHS, true).isNull();
5627}
5628
5629/// mergeTransparentUnionType - if T is a transparent union type and a member
5630/// of T is compatible with SubType, return the merged type, else return
5631/// QualType()
5632QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
5633                                               bool OfBlockPointer,
5634                                               bool Unqualified) {
5635  if (const RecordType *UT = T->getAsUnionType()) {
5636    RecordDecl *UD = UT->getDecl();
5637    if (UD->hasAttr<TransparentUnionAttr>()) {
5638      for (RecordDecl::field_iterator it = UD->field_begin(),
5639           itend = UD->field_end(); it != itend; ++it) {
5640        QualType ET = it->getType().getUnqualifiedType();
5641        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
5642        if (!MT.isNull())
5643          return MT;
5644      }
5645    }
5646  }
5647
5648  return QualType();
5649}
5650
5651/// mergeFunctionArgumentTypes - merge two types which appear as function
5652/// argument types
5653QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
5654                                                bool OfBlockPointer,
5655                                                bool Unqualified) {
5656  // GNU extension: two types are compatible if they appear as a function
5657  // argument, one of the types is a transparent union type and the other
5658  // type is compatible with a union member
5659  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
5660                                              Unqualified);
5661  if (!lmerge.isNull())
5662    return lmerge;
5663
5664  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
5665                                              Unqualified);
5666  if (!rmerge.isNull())
5667    return rmerge;
5668
5669  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
5670}
5671
5672QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
5673                                        bool OfBlockPointer,
5674                                        bool Unqualified) {
5675  const FunctionType *lbase = lhs->getAs<FunctionType>();
5676  const FunctionType *rbase = rhs->getAs<FunctionType>();
5677  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
5678  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
5679  bool allLTypes = true;
5680  bool allRTypes = true;
5681
5682  // Check return type
5683  QualType retType;
5684  if (OfBlockPointer) {
5685    QualType RHS = rbase->getResultType();
5686    QualType LHS = lbase->getResultType();
5687    bool UnqualifiedResult = Unqualified;
5688    if (!UnqualifiedResult)
5689      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
5690    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
5691  }
5692  else
5693    retType = mergeTypes(lbase->getResultType(), rbase->getResultType(), false,
5694                         Unqualified);
5695  if (retType.isNull()) return QualType();
5696
5697  if (Unqualified)
5698    retType = retType.getUnqualifiedType();
5699
5700  CanQualType LRetType = getCanonicalType(lbase->getResultType());
5701  CanQualType RRetType = getCanonicalType(rbase->getResultType());
5702  if (Unqualified) {
5703    LRetType = LRetType.getUnqualifiedType();
5704    RRetType = RRetType.getUnqualifiedType();
5705  }
5706
5707  if (getCanonicalType(retType) != LRetType)
5708    allLTypes = false;
5709  if (getCanonicalType(retType) != RRetType)
5710    allRTypes = false;
5711
5712  // FIXME: double check this
5713  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
5714  //                           rbase->getRegParmAttr() != 0 &&
5715  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
5716  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
5717  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
5718
5719  // Compatible functions must have compatible calling conventions
5720  if (!isSameCallConv(lbaseInfo.getCC(), rbaseInfo.getCC()))
5721    return QualType();
5722
5723  // Regparm is part of the calling convention.
5724  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
5725    return QualType();
5726  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
5727    return QualType();
5728
5729  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
5730    return QualType();
5731
5732  // functypes which return are preferred over those that do not.
5733  if (lbaseInfo.getNoReturn() && !rbaseInfo.getNoReturn())
5734    allLTypes = false;
5735  else if (!lbaseInfo.getNoReturn() && rbaseInfo.getNoReturn())
5736    allRTypes = false;
5737  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
5738  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
5739
5740  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
5741
5742  if (lproto && rproto) { // two C99 style function prototypes
5743    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
5744           "C++ shouldn't be here");
5745    unsigned lproto_nargs = lproto->getNumArgs();
5746    unsigned rproto_nargs = rproto->getNumArgs();
5747
5748    // Compatible functions must have the same number of arguments
5749    if (lproto_nargs != rproto_nargs)
5750      return QualType();
5751
5752    // Variadic and non-variadic functions aren't compatible
5753    if (lproto->isVariadic() != rproto->isVariadic())
5754      return QualType();
5755
5756    if (lproto->getTypeQuals() != rproto->getTypeQuals())
5757      return QualType();
5758
5759    if (LangOpts.ObjCAutoRefCount &&
5760        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
5761      return QualType();
5762
5763    // Check argument compatibility
5764    SmallVector<QualType, 10> types;
5765    for (unsigned i = 0; i < lproto_nargs; i++) {
5766      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
5767      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
5768      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
5769                                                    OfBlockPointer,
5770                                                    Unqualified);
5771      if (argtype.isNull()) return QualType();
5772
5773      if (Unqualified)
5774        argtype = argtype.getUnqualifiedType();
5775
5776      types.push_back(argtype);
5777      if (Unqualified) {
5778        largtype = largtype.getUnqualifiedType();
5779        rargtype = rargtype.getUnqualifiedType();
5780      }
5781
5782      if (getCanonicalType(argtype) != getCanonicalType(largtype))
5783        allLTypes = false;
5784      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
5785        allRTypes = false;
5786    }
5787
5788    if (allLTypes) return lhs;
5789    if (allRTypes) return rhs;
5790
5791    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
5792    EPI.ExtInfo = einfo;
5793    return getFunctionType(retType, types.begin(), types.size(), EPI);
5794  }
5795
5796  if (lproto) allRTypes = false;
5797  if (rproto) allLTypes = false;
5798
5799  const FunctionProtoType *proto = lproto ? lproto : rproto;
5800  if (proto) {
5801    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
5802    if (proto->isVariadic()) return QualType();
5803    // Check that the types are compatible with the types that
5804    // would result from default argument promotions (C99 6.7.5.3p15).
5805    // The only types actually affected are promotable integer
5806    // types and floats, which would be passed as a different
5807    // type depending on whether the prototype is visible.
5808    unsigned proto_nargs = proto->getNumArgs();
5809    for (unsigned i = 0; i < proto_nargs; ++i) {
5810      QualType argTy = proto->getArgType(i);
5811
5812      // Look at the promotion type of enum types, since that is the type used
5813      // to pass enum values.
5814      if (const EnumType *Enum = argTy->getAs<EnumType>())
5815        argTy = Enum->getDecl()->getPromotionType();
5816
5817      if (argTy->isPromotableIntegerType() ||
5818          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
5819        return QualType();
5820    }
5821
5822    if (allLTypes) return lhs;
5823    if (allRTypes) return rhs;
5824
5825    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
5826    EPI.ExtInfo = einfo;
5827    return getFunctionType(retType, proto->arg_type_begin(),
5828                           proto->getNumArgs(), EPI);
5829  }
5830
5831  if (allLTypes) return lhs;
5832  if (allRTypes) return rhs;
5833  return getFunctionNoProtoType(retType, einfo);
5834}
5835
5836QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
5837                                bool OfBlockPointer,
5838                                bool Unqualified, bool BlockReturnType) {
5839  // C++ [expr]: If an expression initially has the type "reference to T", the
5840  // type is adjusted to "T" prior to any further analysis, the expression
5841  // designates the object or function denoted by the reference, and the
5842  // expression is an lvalue unless the reference is an rvalue reference and
5843  // the expression is a function call (possibly inside parentheses).
5844  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
5845  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
5846
5847  if (Unqualified) {
5848    LHS = LHS.getUnqualifiedType();
5849    RHS = RHS.getUnqualifiedType();
5850  }
5851
5852  QualType LHSCan = getCanonicalType(LHS),
5853           RHSCan = getCanonicalType(RHS);
5854
5855  // If two types are identical, they are compatible.
5856  if (LHSCan == RHSCan)
5857    return LHS;
5858
5859  // If the qualifiers are different, the types aren't compatible... mostly.
5860  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5861  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5862  if (LQuals != RQuals) {
5863    // If any of these qualifiers are different, we have a type
5864    // mismatch.
5865    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5866        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
5867        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
5868      return QualType();
5869
5870    // Exactly one GC qualifier difference is allowed: __strong is
5871    // okay if the other type has no GC qualifier but is an Objective
5872    // C object pointer (i.e. implicitly strong by default).  We fix
5873    // this by pretending that the unqualified type was actually
5874    // qualified __strong.
5875    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5876    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5877    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5878
5879    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5880      return QualType();
5881
5882    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
5883      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
5884    }
5885    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
5886      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
5887    }
5888    return QualType();
5889  }
5890
5891  // Okay, qualifiers are equal.
5892
5893  Type::TypeClass LHSClass = LHSCan->getTypeClass();
5894  Type::TypeClass RHSClass = RHSCan->getTypeClass();
5895
5896  // We want to consider the two function types to be the same for these
5897  // comparisons, just force one to the other.
5898  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
5899  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
5900
5901  // Same as above for arrays
5902  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
5903    LHSClass = Type::ConstantArray;
5904  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
5905    RHSClass = Type::ConstantArray;
5906
5907  // ObjCInterfaces are just specialized ObjCObjects.
5908  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
5909  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
5910
5911  // Canonicalize ExtVector -> Vector.
5912  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
5913  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
5914
5915  // If the canonical type classes don't match.
5916  if (LHSClass != RHSClass) {
5917    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
5918    // a signed integer type, or an unsigned integer type.
5919    // Compatibility is based on the underlying type, not the promotion
5920    // type.
5921    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
5922      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
5923        return RHS;
5924    }
5925    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
5926      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
5927        return LHS;
5928    }
5929
5930    return QualType();
5931  }
5932
5933  // The canonical type classes match.
5934  switch (LHSClass) {
5935#define TYPE(Class, Base)
5936#define ABSTRACT_TYPE(Class, Base)
5937#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
5938#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
5939#define DEPENDENT_TYPE(Class, Base) case Type::Class:
5940#include "clang/AST/TypeNodes.def"
5941    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
5942
5943  case Type::LValueReference:
5944  case Type::RValueReference:
5945  case Type::MemberPointer:
5946    llvm_unreachable("C++ should never be in mergeTypes");
5947
5948  case Type::ObjCInterface:
5949  case Type::IncompleteArray:
5950  case Type::VariableArray:
5951  case Type::FunctionProto:
5952  case Type::ExtVector:
5953    llvm_unreachable("Types are eliminated above");
5954
5955  case Type::Pointer:
5956  {
5957    // Merge two pointer types, while trying to preserve typedef info
5958    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
5959    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
5960    if (Unqualified) {
5961      LHSPointee = LHSPointee.getUnqualifiedType();
5962      RHSPointee = RHSPointee.getUnqualifiedType();
5963    }
5964    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
5965                                     Unqualified);
5966    if (ResultType.isNull()) return QualType();
5967    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5968      return LHS;
5969    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5970      return RHS;
5971    return getPointerType(ResultType);
5972  }
5973  case Type::BlockPointer:
5974  {
5975    // Merge two block pointer types, while trying to preserve typedef info
5976    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
5977    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
5978    if (Unqualified) {
5979      LHSPointee = LHSPointee.getUnqualifiedType();
5980      RHSPointee = RHSPointee.getUnqualifiedType();
5981    }
5982    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
5983                                     Unqualified);
5984    if (ResultType.isNull()) return QualType();
5985    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5986      return LHS;
5987    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5988      return RHS;
5989    return getBlockPointerType(ResultType);
5990  }
5991  case Type::Atomic:
5992  {
5993    // Merge two pointer types, while trying to preserve typedef info
5994    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
5995    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
5996    if (Unqualified) {
5997      LHSValue = LHSValue.getUnqualifiedType();
5998      RHSValue = RHSValue.getUnqualifiedType();
5999    }
6000    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
6001                                     Unqualified);
6002    if (ResultType.isNull()) return QualType();
6003    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
6004      return LHS;
6005    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
6006      return RHS;
6007    return getAtomicType(ResultType);
6008  }
6009  case Type::ConstantArray:
6010  {
6011    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
6012    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
6013    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
6014      return QualType();
6015
6016    QualType LHSElem = getAsArrayType(LHS)->getElementType();
6017    QualType RHSElem = getAsArrayType(RHS)->getElementType();
6018    if (Unqualified) {
6019      LHSElem = LHSElem.getUnqualifiedType();
6020      RHSElem = RHSElem.getUnqualifiedType();
6021    }
6022
6023    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
6024    if (ResultType.isNull()) return QualType();
6025    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
6026      return LHS;
6027    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
6028      return RHS;
6029    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
6030                                          ArrayType::ArraySizeModifier(), 0);
6031    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
6032                                          ArrayType::ArraySizeModifier(), 0);
6033    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
6034    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
6035    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
6036      return LHS;
6037    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
6038      return RHS;
6039    if (LVAT) {
6040      // FIXME: This isn't correct! But tricky to implement because
6041      // the array's size has to be the size of LHS, but the type
6042      // has to be different.
6043      return LHS;
6044    }
6045    if (RVAT) {
6046      // FIXME: This isn't correct! But tricky to implement because
6047      // the array's size has to be the size of RHS, but the type
6048      // has to be different.
6049      return RHS;
6050    }
6051    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
6052    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
6053    return getIncompleteArrayType(ResultType,
6054                                  ArrayType::ArraySizeModifier(), 0);
6055  }
6056  case Type::FunctionNoProto:
6057    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
6058  case Type::Record:
6059  case Type::Enum:
6060    return QualType();
6061  case Type::Builtin:
6062    // Only exactly equal builtin types are compatible, which is tested above.
6063    return QualType();
6064  case Type::Complex:
6065    // Distinct complex types are incompatible.
6066    return QualType();
6067  case Type::Vector:
6068    // FIXME: The merged type should be an ExtVector!
6069    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
6070                             RHSCan->getAs<VectorType>()))
6071      return LHS;
6072    return QualType();
6073  case Type::ObjCObject: {
6074    // Check if the types are assignment compatible.
6075    // FIXME: This should be type compatibility, e.g. whether
6076    // "LHS x; RHS x;" at global scope is legal.
6077    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
6078    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
6079    if (canAssignObjCInterfaces(LHSIface, RHSIface))
6080      return LHS;
6081
6082    return QualType();
6083  }
6084  case Type::ObjCObjectPointer: {
6085    if (OfBlockPointer) {
6086      if (canAssignObjCInterfacesInBlockPointer(
6087                                          LHS->getAs<ObjCObjectPointerType>(),
6088                                          RHS->getAs<ObjCObjectPointerType>(),
6089                                          BlockReturnType))
6090      return LHS;
6091      return QualType();
6092    }
6093    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
6094                                RHS->getAs<ObjCObjectPointerType>()))
6095      return LHS;
6096
6097    return QualType();
6098    }
6099  }
6100
6101  return QualType();
6102}
6103
6104bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
6105                   const FunctionProtoType *FromFunctionType,
6106                   const FunctionProtoType *ToFunctionType) {
6107  if (FromFunctionType->hasAnyConsumedArgs() !=
6108      ToFunctionType->hasAnyConsumedArgs())
6109    return false;
6110  FunctionProtoType::ExtProtoInfo FromEPI =
6111    FromFunctionType->getExtProtoInfo();
6112  FunctionProtoType::ExtProtoInfo ToEPI =
6113    ToFunctionType->getExtProtoInfo();
6114  if (FromEPI.ConsumedArguments && ToEPI.ConsumedArguments)
6115    for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs();
6116         ArgIdx != NumArgs; ++ArgIdx)  {
6117      if (FromEPI.ConsumedArguments[ArgIdx] !=
6118          ToEPI.ConsumedArguments[ArgIdx])
6119        return false;
6120    }
6121  return true;
6122}
6123
6124/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
6125/// 'RHS' attributes and returns the merged version; including for function
6126/// return types.
6127QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
6128  QualType LHSCan = getCanonicalType(LHS),
6129  RHSCan = getCanonicalType(RHS);
6130  // If two types are identical, they are compatible.
6131  if (LHSCan == RHSCan)
6132    return LHS;
6133  if (RHSCan->isFunctionType()) {
6134    if (!LHSCan->isFunctionType())
6135      return QualType();
6136    QualType OldReturnType =
6137      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
6138    QualType NewReturnType =
6139      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
6140    QualType ResReturnType =
6141      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
6142    if (ResReturnType.isNull())
6143      return QualType();
6144    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
6145      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
6146      // In either case, use OldReturnType to build the new function type.
6147      const FunctionType *F = LHS->getAs<FunctionType>();
6148      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
6149        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
6150        EPI.ExtInfo = getFunctionExtInfo(LHS);
6151        QualType ResultType
6152          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
6153                            FPT->getNumArgs(), EPI);
6154        return ResultType;
6155      }
6156    }
6157    return QualType();
6158  }
6159
6160  // If the qualifiers are different, the types can still be merged.
6161  Qualifiers LQuals = LHSCan.getLocalQualifiers();
6162  Qualifiers RQuals = RHSCan.getLocalQualifiers();
6163  if (LQuals != RQuals) {
6164    // If any of these qualifiers are different, we have a type mismatch.
6165    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
6166        LQuals.getAddressSpace() != RQuals.getAddressSpace())
6167      return QualType();
6168
6169    // Exactly one GC qualifier difference is allowed: __strong is
6170    // okay if the other type has no GC qualifier but is an Objective
6171    // C object pointer (i.e. implicitly strong by default).  We fix
6172    // this by pretending that the unqualified type was actually
6173    // qualified __strong.
6174    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
6175    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
6176    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
6177
6178    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
6179      return QualType();
6180
6181    if (GC_L == Qualifiers::Strong)
6182      return LHS;
6183    if (GC_R == Qualifiers::Strong)
6184      return RHS;
6185    return QualType();
6186  }
6187
6188  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
6189    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6190    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6191    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
6192    if (ResQT == LHSBaseQT)
6193      return LHS;
6194    if (ResQT == RHSBaseQT)
6195      return RHS;
6196  }
6197  return QualType();
6198}
6199
6200//===----------------------------------------------------------------------===//
6201//                         Integer Predicates
6202//===----------------------------------------------------------------------===//
6203
6204unsigned ASTContext::getIntWidth(QualType T) const {
6205  if (const EnumType *ET = dyn_cast<EnumType>(T))
6206    T = ET->getDecl()->getIntegerType();
6207  if (T->isBooleanType())
6208    return 1;
6209  // For builtin types, just use the standard type sizing method
6210  return (unsigned)getTypeSize(T);
6211}
6212
6213QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
6214  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
6215
6216  // Turn <4 x signed int> -> <4 x unsigned int>
6217  if (const VectorType *VTy = T->getAs<VectorType>())
6218    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
6219                         VTy->getNumElements(), VTy->getVectorKind());
6220
6221  // For enums, we return the unsigned version of the base type.
6222  if (const EnumType *ETy = T->getAs<EnumType>())
6223    T = ETy->getDecl()->getIntegerType();
6224
6225  const BuiltinType *BTy = T->getAs<BuiltinType>();
6226  assert(BTy && "Unexpected signed integer type");
6227  switch (BTy->getKind()) {
6228  case BuiltinType::Char_S:
6229  case BuiltinType::SChar:
6230    return UnsignedCharTy;
6231  case BuiltinType::Short:
6232    return UnsignedShortTy;
6233  case BuiltinType::Int:
6234    return UnsignedIntTy;
6235  case BuiltinType::Long:
6236    return UnsignedLongTy;
6237  case BuiltinType::LongLong:
6238    return UnsignedLongLongTy;
6239  case BuiltinType::Int128:
6240    return UnsignedInt128Ty;
6241  default:
6242    llvm_unreachable("Unexpected signed integer type");
6243  }
6244}
6245
6246ASTMutationListener::~ASTMutationListener() { }
6247
6248
6249//===----------------------------------------------------------------------===//
6250//                          Builtin Type Computation
6251//===----------------------------------------------------------------------===//
6252
6253/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
6254/// pointer over the consumed characters.  This returns the resultant type.  If
6255/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
6256/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
6257/// a vector of "i*".
6258///
6259/// RequiresICE is filled in on return to indicate whether the value is required
6260/// to be an Integer Constant Expression.
6261static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
6262                                  ASTContext::GetBuiltinTypeError &Error,
6263                                  bool &RequiresICE,
6264                                  bool AllowTypeModifiers) {
6265  // Modifiers.
6266  int HowLong = 0;
6267  bool Signed = false, Unsigned = false;
6268  RequiresICE = false;
6269
6270  // Read the prefixed modifiers first.
6271  bool Done = false;
6272  while (!Done) {
6273    switch (*Str++) {
6274    default: Done = true; --Str; break;
6275    case 'I':
6276      RequiresICE = true;
6277      break;
6278    case 'S':
6279      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
6280      assert(!Signed && "Can't use 'S' modifier multiple times!");
6281      Signed = true;
6282      break;
6283    case 'U':
6284      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
6285      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
6286      Unsigned = true;
6287      break;
6288    case 'L':
6289      assert(HowLong <= 2 && "Can't have LLLL modifier");
6290      ++HowLong;
6291      break;
6292    }
6293  }
6294
6295  QualType Type;
6296
6297  // Read the base type.
6298  switch (*Str++) {
6299  default: llvm_unreachable("Unknown builtin type letter!");
6300  case 'v':
6301    assert(HowLong == 0 && !Signed && !Unsigned &&
6302           "Bad modifiers used with 'v'!");
6303    Type = Context.VoidTy;
6304    break;
6305  case 'f':
6306    assert(HowLong == 0 && !Signed && !Unsigned &&
6307           "Bad modifiers used with 'f'!");
6308    Type = Context.FloatTy;
6309    break;
6310  case 'd':
6311    assert(HowLong < 2 && !Signed && !Unsigned &&
6312           "Bad modifiers used with 'd'!");
6313    if (HowLong)
6314      Type = Context.LongDoubleTy;
6315    else
6316      Type = Context.DoubleTy;
6317    break;
6318  case 's':
6319    assert(HowLong == 0 && "Bad modifiers used with 's'!");
6320    if (Unsigned)
6321      Type = Context.UnsignedShortTy;
6322    else
6323      Type = Context.ShortTy;
6324    break;
6325  case 'i':
6326    if (HowLong == 3)
6327      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
6328    else if (HowLong == 2)
6329      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
6330    else if (HowLong == 1)
6331      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
6332    else
6333      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
6334    break;
6335  case 'c':
6336    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
6337    if (Signed)
6338      Type = Context.SignedCharTy;
6339    else if (Unsigned)
6340      Type = Context.UnsignedCharTy;
6341    else
6342      Type = Context.CharTy;
6343    break;
6344  case 'b': // boolean
6345    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
6346    Type = Context.BoolTy;
6347    break;
6348  case 'z':  // size_t.
6349    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
6350    Type = Context.getSizeType();
6351    break;
6352  case 'F':
6353    Type = Context.getCFConstantStringType();
6354    break;
6355  case 'G':
6356    Type = Context.getObjCIdType();
6357    break;
6358  case 'H':
6359    Type = Context.getObjCSelType();
6360    break;
6361  case 'a':
6362    Type = Context.getBuiltinVaListType();
6363    assert(!Type.isNull() && "builtin va list type not initialized!");
6364    break;
6365  case 'A':
6366    // This is a "reference" to a va_list; however, what exactly
6367    // this means depends on how va_list is defined. There are two
6368    // different kinds of va_list: ones passed by value, and ones
6369    // passed by reference.  An example of a by-value va_list is
6370    // x86, where va_list is a char*. An example of by-ref va_list
6371    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
6372    // we want this argument to be a char*&; for x86-64, we want
6373    // it to be a __va_list_tag*.
6374    Type = Context.getBuiltinVaListType();
6375    assert(!Type.isNull() && "builtin va list type not initialized!");
6376    if (Type->isArrayType())
6377      Type = Context.getArrayDecayedType(Type);
6378    else
6379      Type = Context.getLValueReferenceType(Type);
6380    break;
6381  case 'V': {
6382    char *End;
6383    unsigned NumElements = strtoul(Str, &End, 10);
6384    assert(End != Str && "Missing vector size");
6385    Str = End;
6386
6387    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
6388                                             RequiresICE, false);
6389    assert(!RequiresICE && "Can't require vector ICE");
6390
6391    // TODO: No way to make AltiVec vectors in builtins yet.
6392    Type = Context.getVectorType(ElementType, NumElements,
6393                                 VectorType::GenericVector);
6394    break;
6395  }
6396  case 'X': {
6397    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
6398                                             false);
6399    assert(!RequiresICE && "Can't require complex ICE");
6400    Type = Context.getComplexType(ElementType);
6401    break;
6402  }
6403  case 'Y' : {
6404    Type = Context.getPointerDiffType();
6405    break;
6406  }
6407  case 'P':
6408    Type = Context.getFILEType();
6409    if (Type.isNull()) {
6410      Error = ASTContext::GE_Missing_stdio;
6411      return QualType();
6412    }
6413    break;
6414  case 'J':
6415    if (Signed)
6416      Type = Context.getsigjmp_bufType();
6417    else
6418      Type = Context.getjmp_bufType();
6419
6420    if (Type.isNull()) {
6421      Error = ASTContext::GE_Missing_setjmp;
6422      return QualType();
6423    }
6424    break;
6425  case 'K':
6426    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'K'!");
6427    Type = Context.getucontext_tType();
6428
6429    if (Type.isNull()) {
6430      Error = ASTContext::GE_Missing_ucontext;
6431      return QualType();
6432    }
6433    break;
6434  }
6435
6436  // If there are modifiers and if we're allowed to parse them, go for it.
6437  Done = !AllowTypeModifiers;
6438  while (!Done) {
6439    switch (char c = *Str++) {
6440    default: Done = true; --Str; break;
6441    case '*':
6442    case '&': {
6443      // Both pointers and references can have their pointee types
6444      // qualified with an address space.
6445      char *End;
6446      unsigned AddrSpace = strtoul(Str, &End, 10);
6447      if (End != Str && AddrSpace != 0) {
6448        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
6449        Str = End;
6450      }
6451      if (c == '*')
6452        Type = Context.getPointerType(Type);
6453      else
6454        Type = Context.getLValueReferenceType(Type);
6455      break;
6456    }
6457    // FIXME: There's no way to have a built-in with an rvalue ref arg.
6458    case 'C':
6459      Type = Type.withConst();
6460      break;
6461    case 'D':
6462      Type = Context.getVolatileType(Type);
6463      break;
6464    }
6465  }
6466
6467  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
6468         "Integer constant 'I' type must be an integer");
6469
6470  return Type;
6471}
6472
6473/// GetBuiltinType - Return the type for the specified builtin.
6474QualType ASTContext::GetBuiltinType(unsigned Id,
6475                                    GetBuiltinTypeError &Error,
6476                                    unsigned *IntegerConstantArgs) const {
6477  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
6478
6479  SmallVector<QualType, 8> ArgTypes;
6480
6481  bool RequiresICE = false;
6482  Error = GE_None;
6483  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
6484                                       RequiresICE, true);
6485  if (Error != GE_None)
6486    return QualType();
6487
6488  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
6489
6490  while (TypeStr[0] && TypeStr[0] != '.') {
6491    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
6492    if (Error != GE_None)
6493      return QualType();
6494
6495    // If this argument is required to be an IntegerConstantExpression and the
6496    // caller cares, fill in the bitmask we return.
6497    if (RequiresICE && IntegerConstantArgs)
6498      *IntegerConstantArgs |= 1 << ArgTypes.size();
6499
6500    // Do array -> pointer decay.  The builtin should use the decayed type.
6501    if (Ty->isArrayType())
6502      Ty = getArrayDecayedType(Ty);
6503
6504    ArgTypes.push_back(Ty);
6505  }
6506
6507  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
6508         "'.' should only occur at end of builtin type list!");
6509
6510  FunctionType::ExtInfo EI;
6511  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
6512
6513  bool Variadic = (TypeStr[0] == '.');
6514
6515  // We really shouldn't be making a no-proto type here, especially in C++.
6516  if (ArgTypes.empty() && Variadic)
6517    return getFunctionNoProtoType(ResType, EI);
6518
6519  FunctionProtoType::ExtProtoInfo EPI;
6520  EPI.ExtInfo = EI;
6521  EPI.Variadic = Variadic;
6522
6523  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(), EPI);
6524}
6525
6526GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
6527  GVALinkage External = GVA_StrongExternal;
6528
6529  Linkage L = FD->getLinkage();
6530  switch (L) {
6531  case NoLinkage:
6532  case InternalLinkage:
6533  case UniqueExternalLinkage:
6534    return GVA_Internal;
6535
6536  case ExternalLinkage:
6537    switch (FD->getTemplateSpecializationKind()) {
6538    case TSK_Undeclared:
6539    case TSK_ExplicitSpecialization:
6540      External = GVA_StrongExternal;
6541      break;
6542
6543    case TSK_ExplicitInstantiationDefinition:
6544      return GVA_ExplicitTemplateInstantiation;
6545
6546    case TSK_ExplicitInstantiationDeclaration:
6547    case TSK_ImplicitInstantiation:
6548      External = GVA_TemplateInstantiation;
6549      break;
6550    }
6551  }
6552
6553  if (!FD->isInlined())
6554    return External;
6555
6556  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
6557    // GNU or C99 inline semantics. Determine whether this symbol should be
6558    // externally visible.
6559    if (FD->isInlineDefinitionExternallyVisible())
6560      return External;
6561
6562    // C99 inline semantics, where the symbol is not externally visible.
6563    return GVA_C99Inline;
6564  }
6565
6566  // C++0x [temp.explicit]p9:
6567  //   [ Note: The intent is that an inline function that is the subject of
6568  //   an explicit instantiation declaration will still be implicitly
6569  //   instantiated when used so that the body can be considered for
6570  //   inlining, but that no out-of-line copy of the inline function would be
6571  //   generated in the translation unit. -- end note ]
6572  if (FD->getTemplateSpecializationKind()
6573                                       == TSK_ExplicitInstantiationDeclaration)
6574    return GVA_C99Inline;
6575
6576  return GVA_CXXInline;
6577}
6578
6579GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
6580  // If this is a static data member, compute the kind of template
6581  // specialization. Otherwise, this variable is not part of a
6582  // template.
6583  TemplateSpecializationKind TSK = TSK_Undeclared;
6584  if (VD->isStaticDataMember())
6585    TSK = VD->getTemplateSpecializationKind();
6586
6587  Linkage L = VD->getLinkage();
6588  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
6589      VD->getType()->getLinkage() == UniqueExternalLinkage)
6590    L = UniqueExternalLinkage;
6591
6592  switch (L) {
6593  case NoLinkage:
6594  case InternalLinkage:
6595  case UniqueExternalLinkage:
6596    return GVA_Internal;
6597
6598  case ExternalLinkage:
6599    switch (TSK) {
6600    case TSK_Undeclared:
6601    case TSK_ExplicitSpecialization:
6602      return GVA_StrongExternal;
6603
6604    case TSK_ExplicitInstantiationDeclaration:
6605      llvm_unreachable("Variable should not be instantiated");
6606      // Fall through to treat this like any other instantiation.
6607
6608    case TSK_ExplicitInstantiationDefinition:
6609      return GVA_ExplicitTemplateInstantiation;
6610
6611    case TSK_ImplicitInstantiation:
6612      return GVA_TemplateInstantiation;
6613    }
6614  }
6615
6616  return GVA_StrongExternal;
6617}
6618
6619bool ASTContext::DeclMustBeEmitted(const Decl *D) {
6620  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
6621    if (!VD->isFileVarDecl())
6622      return false;
6623  } else if (!isa<FunctionDecl>(D))
6624    return false;
6625
6626  // Weak references don't produce any output by themselves.
6627  if (D->hasAttr<WeakRefAttr>())
6628    return false;
6629
6630  // Aliases and used decls are required.
6631  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
6632    return true;
6633
6634  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
6635    // Forward declarations aren't required.
6636    if (!FD->doesThisDeclarationHaveABody())
6637      return FD->doesDeclarationForceExternallyVisibleDefinition();
6638
6639    // Constructors and destructors are required.
6640    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
6641      return true;
6642
6643    // The key function for a class is required.
6644    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
6645      const CXXRecordDecl *RD = MD->getParent();
6646      if (MD->isOutOfLine() && RD->isDynamicClass()) {
6647        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
6648        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
6649          return true;
6650      }
6651    }
6652
6653    GVALinkage Linkage = GetGVALinkageForFunction(FD);
6654
6655    // static, static inline, always_inline, and extern inline functions can
6656    // always be deferred.  Normal inline functions can be deferred in C99/C++.
6657    // Implicit template instantiations can also be deferred in C++.
6658    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
6659        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
6660      return false;
6661    return true;
6662  }
6663
6664  const VarDecl *VD = cast<VarDecl>(D);
6665  assert(VD->isFileVarDecl() && "Expected file scoped var");
6666
6667  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
6668    return false;
6669
6670  // Structs that have non-trivial constructors or destructors are required.
6671
6672  // FIXME: Handle references.
6673  // FIXME: Be more selective about which constructors we care about.
6674  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
6675    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
6676      if (RD->hasDefinition() && !(RD->hasTrivialDefaultConstructor() &&
6677                                   RD->hasTrivialCopyConstructor() &&
6678                                   RD->hasTrivialMoveConstructor() &&
6679                                   RD->hasTrivialDestructor()))
6680        return true;
6681    }
6682  }
6683
6684  GVALinkage L = GetGVALinkageForVariable(VD);
6685  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
6686    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
6687      return false;
6688  }
6689
6690  return true;
6691}
6692
6693CallingConv ASTContext::getDefaultMethodCallConv() {
6694  // Pass through to the C++ ABI object
6695  return ABI->getDefaultMethodCallConv();
6696}
6697
6698bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
6699  // Pass through to the C++ ABI object
6700  return ABI->isNearlyEmpty(RD);
6701}
6702
6703MangleContext *ASTContext::createMangleContext() {
6704  switch (Target->getCXXABI()) {
6705  case CXXABI_ARM:
6706  case CXXABI_Itanium:
6707    return createItaniumMangleContext(*this, getDiagnostics());
6708  case CXXABI_Microsoft:
6709    return createMicrosoftMangleContext(*this, getDiagnostics());
6710  }
6711  llvm_unreachable("Unsupported ABI");
6712}
6713
6714CXXABI::~CXXABI() {}
6715
6716size_t ASTContext::getSideTableAllocatedMemory() const {
6717  return ASTRecordLayouts.getMemorySize()
6718    + llvm::capacity_in_bytes(ObjCLayouts)
6719    + llvm::capacity_in_bytes(KeyFunctions)
6720    + llvm::capacity_in_bytes(ObjCImpls)
6721    + llvm::capacity_in_bytes(BlockVarCopyInits)
6722    + llvm::capacity_in_bytes(DeclAttrs)
6723    + llvm::capacity_in_bytes(InstantiatedFromStaticDataMember)
6724    + llvm::capacity_in_bytes(InstantiatedFromUsingDecl)
6725    + llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl)
6726    + llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl)
6727    + llvm::capacity_in_bytes(OverriddenMethods)
6728    + llvm::capacity_in_bytes(Types)
6729    + llvm::capacity_in_bytes(VariableArrayTypes)
6730    + llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
6731}
6732
6733void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
6734  ParamIndices[D] = index;
6735}
6736
6737unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
6738  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
6739  assert(I != ParamIndices.end() &&
6740         "ParmIndices lacks entry set by ParmVarDecl");
6741  return I->second;
6742}
6743