ASTContext.cpp revision 4dc34ebf2a0716bf77ba110dab6777a3fc4397dd 
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().getCanonicalType().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          QualType T = NTTP->getExpansionType(I);
83          ID.AddPointer(T.getCanonicalType().getAsOpaquePtr());
84        }
85      } else
86        ID.AddBoolean(false);
87      continue;
88    }
89
90    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
91    ID.AddInteger(2);
92    Profile(ID, TTP);
93  }
94}
95
96TemplateTemplateParmDecl *
97ASTContext::getCanonicalTemplateTemplateParmDecl(
98                                          TemplateTemplateParmDecl *TTP) const {
99  // Check if we already have a canonical template template parameter.
100  llvm::FoldingSetNodeID ID;
101  CanonicalTemplateTemplateParm::Profile(ID, TTP);
102  void *InsertPos = 0;
103  CanonicalTemplateTemplateParm *Canonical
104    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
105  if (Canonical)
106    return Canonical->getParam();
107
108  // Build a canonical template parameter list.
109  TemplateParameterList *Params = TTP->getTemplateParameters();
110  SmallVector<NamedDecl *, 4> CanonParams;
111  CanonParams.reserve(Params->size());
112  for (TemplateParameterList::const_iterator P = Params->begin(),
113                                          PEnd = Params->end();
114       P != PEnd; ++P) {
115    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
116      CanonParams.push_back(
117                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
118                                               SourceLocation(),
119                                               SourceLocation(),
120                                               TTP->getDepth(),
121                                               TTP->getIndex(), 0, false,
122                                               TTP->isParameterPack()));
123    else if (NonTypeTemplateParmDecl *NTTP
124             = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
125      QualType T = getCanonicalType(NTTP->getType());
126      TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
127      NonTypeTemplateParmDecl *Param;
128      if (NTTP->isExpandedParameterPack()) {
129        SmallVector<QualType, 2> ExpandedTypes;
130        SmallVector<TypeSourceInfo *, 2> ExpandedTInfos;
131        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
132          ExpandedTypes.push_back(getCanonicalType(NTTP->getExpansionType(I)));
133          ExpandedTInfos.push_back(
134                                getTrivialTypeSourceInfo(ExpandedTypes.back()));
135        }
136
137        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
138                                                SourceLocation(),
139                                                SourceLocation(),
140                                                NTTP->getDepth(),
141                                                NTTP->getPosition(), 0,
142                                                T,
143                                                TInfo,
144                                                ExpandedTypes.data(),
145                                                ExpandedTypes.size(),
146                                                ExpandedTInfos.data());
147      } else {
148        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
149                                                SourceLocation(),
150                                                SourceLocation(),
151                                                NTTP->getDepth(),
152                                                NTTP->getPosition(), 0,
153                                                T,
154                                                NTTP->isParameterPack(),
155                                                TInfo);
156      }
157      CanonParams.push_back(Param);
158
159    } else
160      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
161                                           cast<TemplateTemplateParmDecl>(*P)));
162  }
163
164  TemplateTemplateParmDecl *CanonTTP
165    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
166                                       SourceLocation(), TTP->getDepth(),
167                                       TTP->getPosition(),
168                                       TTP->isParameterPack(),
169                                       0,
170                         TemplateParameterList::Create(*this, SourceLocation(),
171                                                       SourceLocation(),
172                                                       CanonParams.data(),
173                                                       CanonParams.size(),
174                                                       SourceLocation()));
175
176  // Get the new insert position for the node we care about.
177  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
178  assert(Canonical == 0 && "Shouldn't be in the map!");
179  (void)Canonical;
180
181  // Create the canonical template template parameter entry.
182  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
183  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
184  return CanonTTP;
185}
186
187CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
188  if (!LangOpts.CPlusPlus) return 0;
189
190  switch (T.getCXXABI()) {
191  case CXXABI_ARM:
192    return CreateARMCXXABI(*this);
193  case CXXABI_Itanium:
194    return CreateItaniumCXXABI(*this);
195  case CXXABI_Microsoft:
196    return CreateMicrosoftCXXABI(*this);
197  }
198  llvm_unreachable("Invalid CXXABI type!");
199}
200
201static const LangAS::Map *getAddressSpaceMap(const TargetInfo &T,
202                                             const LangOptions &LOpts) {
203  if (LOpts.FakeAddressSpaceMap) {
204    // The fake address space map must have a distinct entry for each
205    // language-specific address space.
206    static const unsigned FakeAddrSpaceMap[] = {
207      1, // opencl_global
208      2, // opencl_local
209      3, // opencl_constant
210      4, // cuda_device
211      5, // cuda_constant
212      6  // cuda_shared
213    };
214    return &FakeAddrSpaceMap;
215  } else {
216    return &T.getAddressSpaceMap();
217  }
218}
219
220ASTContext::ASTContext(LangOptions& LOpts, SourceManager &SM,
221                       const TargetInfo *t,
222                       IdentifierTable &idents, SelectorTable &sels,
223                       Builtin::Context &builtins,
224                       unsigned size_reserve,
225                       bool DelayInitialization)
226  : FunctionProtoTypes(this_()),
227    TemplateSpecializationTypes(this_()),
228    DependentTemplateSpecializationTypes(this_()),
229    SubstTemplateTemplateParmPacks(this_()),
230    GlobalNestedNameSpecifier(0),
231    Int128Decl(0), UInt128Decl(0),
232    ObjCIdDecl(0), ObjCSelDecl(0), ObjCClassDecl(0), ObjCProtocolClassDecl(0),
233    CFConstantStringTypeDecl(0), ObjCInstanceTypeDecl(0),
234    FILEDecl(0),
235    jmp_bufDecl(0), sigjmp_bufDecl(0), ucontext_tDecl(0),
236    BlockDescriptorType(0), BlockDescriptorExtendedType(0),
237    cudaConfigureCallDecl(0),
238    NullTypeSourceInfo(QualType()),
239    FirstLocalImport(), LastLocalImport(),
240    SourceMgr(SM), LangOpts(LOpts),
241    AddrSpaceMap(0), Target(t), PrintingPolicy(LOpts),
242    Idents(idents), Selectors(sels),
243    BuiltinInfo(builtins),
244    DeclarationNames(*this),
245    ExternalSource(0), Listener(0),
246    LastSDM(0, 0),
247    UniqueBlockByRefTypeID(0)
248{
249  if (size_reserve > 0) Types.reserve(size_reserve);
250  TUDecl = TranslationUnitDecl::Create(*this);
251
252  if (!DelayInitialization) {
253    assert(t && "No target supplied for ASTContext initialization");
254    InitBuiltinTypes(*t);
255  }
256}
257
258ASTContext::~ASTContext() {
259  // Release the DenseMaps associated with DeclContext objects.
260  // FIXME: Is this the ideal solution?
261  ReleaseDeclContextMaps();
262
263  // Call all of the deallocation functions.
264  for (unsigned I = 0, N = Deallocations.size(); I != N; ++I)
265    Deallocations[I].first(Deallocations[I].second);
266
267  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
268  // because they can contain DenseMaps.
269  for (llvm::DenseMap<const ObjCContainerDecl*,
270       const ASTRecordLayout*>::iterator
271       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
272    // Increment in loop to prevent using deallocated memory.
273    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
274      R->Destroy(*this);
275
276  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
277       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
278    // Increment in loop to prevent using deallocated memory.
279    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
280      R->Destroy(*this);
281  }
282
283  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
284                                                    AEnd = DeclAttrs.end();
285       A != AEnd; ++A)
286    A->second->~AttrVec();
287}
288
289void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
290  Deallocations.push_back(std::make_pair(Callback, Data));
291}
292
293void
294ASTContext::setExternalSource(OwningPtr<ExternalASTSource> &Source) {
295  ExternalSource.reset(Source.take());
296}
297
298void ASTContext::PrintStats() const {
299  llvm::errs() << "\n*** AST Context Stats:\n";
300  llvm::errs() << "  " << Types.size() << " types total.\n";
301
302  unsigned counts[] = {
303#define TYPE(Name, Parent) 0,
304#define ABSTRACT_TYPE(Name, Parent)
305#include "clang/AST/TypeNodes.def"
306    0 // Extra
307  };
308
309  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
310    Type *T = Types[i];
311    counts[(unsigned)T->getTypeClass()]++;
312  }
313
314  unsigned Idx = 0;
315  unsigned TotalBytes = 0;
316#define TYPE(Name, Parent)                                              \
317  if (counts[Idx])                                                      \
318    llvm::errs() << "    " << counts[Idx] << " " << #Name               \
319                 << " types\n";                                         \
320  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
321  ++Idx;
322#define ABSTRACT_TYPE(Name, Parent)
323#include "clang/AST/TypeNodes.def"
324
325  llvm::errs() << "Total bytes = " << TotalBytes << "\n";
326
327  // Implicit special member functions.
328  llvm::errs() << NumImplicitDefaultConstructorsDeclared << "/"
329               << NumImplicitDefaultConstructors
330               << " implicit default constructors created\n";
331  llvm::errs() << NumImplicitCopyConstructorsDeclared << "/"
332               << NumImplicitCopyConstructors
333               << " implicit copy constructors created\n";
334  if (getLangOpts().CPlusPlus)
335    llvm::errs() << NumImplicitMoveConstructorsDeclared << "/"
336                 << NumImplicitMoveConstructors
337                 << " implicit move constructors created\n";
338  llvm::errs() << NumImplicitCopyAssignmentOperatorsDeclared << "/"
339               << NumImplicitCopyAssignmentOperators
340               << " implicit copy assignment operators created\n";
341  if (getLangOpts().CPlusPlus)
342    llvm::errs() << NumImplicitMoveAssignmentOperatorsDeclared << "/"
343                 << NumImplicitMoveAssignmentOperators
344                 << " implicit move assignment operators created\n";
345  llvm::errs() << NumImplicitDestructorsDeclared << "/"
346               << NumImplicitDestructors
347               << " implicit destructors created\n";
348
349  if (ExternalSource.get()) {
350    llvm::errs() << "\n";
351    ExternalSource->PrintStats();
352  }
353
354  BumpAlloc.PrintStats();
355}
356
357TypedefDecl *ASTContext::getInt128Decl() const {
358  if (!Int128Decl) {
359    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(Int128Ty);
360    Int128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
361                                     getTranslationUnitDecl(),
362                                     SourceLocation(),
363                                     SourceLocation(),
364                                     &Idents.get("__int128_t"),
365                                     TInfo);
366  }
367
368  return Int128Decl;
369}
370
371TypedefDecl *ASTContext::getUInt128Decl() const {
372  if (!UInt128Decl) {
373    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(UnsignedInt128Ty);
374    UInt128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
375                                     getTranslationUnitDecl(),
376                                     SourceLocation(),
377                                     SourceLocation(),
378                                     &Idents.get("__uint128_t"),
379                                     TInfo);
380  }
381
382  return UInt128Decl;
383}
384
385void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
386  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
387  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
388  Types.push_back(Ty);
389}
390
391void ASTContext::InitBuiltinTypes(const TargetInfo &Target) {
392  assert((!this->Target || this->Target == &Target) &&
393         "Incorrect target reinitialization");
394  assert(VoidTy.isNull() && "Context reinitialized?");
395
396  this->Target = &Target;
397
398  ABI.reset(createCXXABI(Target));
399  AddrSpaceMap = getAddressSpaceMap(Target, LangOpts);
400
401  // C99 6.2.5p19.
402  InitBuiltinType(VoidTy,              BuiltinType::Void);
403
404  // C99 6.2.5p2.
405  InitBuiltinType(BoolTy,              BuiltinType::Bool);
406  // C99 6.2.5p3.
407  if (LangOpts.CharIsSigned)
408    InitBuiltinType(CharTy,            BuiltinType::Char_S);
409  else
410    InitBuiltinType(CharTy,            BuiltinType::Char_U);
411  // C99 6.2.5p4.
412  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
413  InitBuiltinType(ShortTy,             BuiltinType::Short);
414  InitBuiltinType(IntTy,               BuiltinType::Int);
415  InitBuiltinType(LongTy,              BuiltinType::Long);
416  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
417
418  // C99 6.2.5p6.
419  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
420  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
421  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
422  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
423  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
424
425  // C99 6.2.5p10.
426  InitBuiltinType(FloatTy,             BuiltinType::Float);
427  InitBuiltinType(DoubleTy,            BuiltinType::Double);
428  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
429
430  // GNU extension, 128-bit integers.
431  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
432  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
433
434  if (LangOpts.CPlusPlus) { // C++ 3.9.1p5
435    if (TargetInfo::isTypeSigned(Target.getWCharType()))
436      InitBuiltinType(WCharTy,           BuiltinType::WChar_S);
437    else  // -fshort-wchar makes wchar_t be unsigned.
438      InitBuiltinType(WCharTy,           BuiltinType::WChar_U);
439  } else // C99
440    WCharTy = getFromTargetType(Target.getWCharType());
441
442  WIntTy = getFromTargetType(Target.getWIntType());
443
444  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
445    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
446  else // C99
447    Char16Ty = getFromTargetType(Target.getChar16Type());
448
449  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
450    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
451  else // C99
452    Char32Ty = getFromTargetType(Target.getChar32Type());
453
454  // Placeholder type for type-dependent expressions whose type is
455  // completely unknown. No code should ever check a type against
456  // DependentTy and users should never see it; however, it is here to
457  // help diagnose failures to properly check for type-dependent
458  // expressions.
459  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
460
461  // Placeholder type for functions.
462  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
463
464  // Placeholder type for bound members.
465  InitBuiltinType(BoundMemberTy,       BuiltinType::BoundMember);
466
467  // Placeholder type for pseudo-objects.
468  InitBuiltinType(PseudoObjectTy,      BuiltinType::PseudoObject);
469
470  // "any" type; useful for debugger-like clients.
471  InitBuiltinType(UnknownAnyTy,        BuiltinType::UnknownAny);
472
473  // Placeholder type for unbridged ARC casts.
474  InitBuiltinType(ARCUnbridgedCastTy,  BuiltinType::ARCUnbridgedCast);
475
476  // C99 6.2.5p11.
477  FloatComplexTy      = getComplexType(FloatTy);
478  DoubleComplexTy     = getComplexType(DoubleTy);
479  LongDoubleComplexTy = getComplexType(LongDoubleTy);
480
481  BuiltinVaListType = QualType();
482
483  // Builtin types for 'id', 'Class', and 'SEL'.
484  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
485  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
486  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
487
488  // Builtin type for __objc_yes and __objc_no
489  ObjCBuiltinBoolTy = (Target.useSignedCharForObjCBool() ?
490                       SignedCharTy : BoolTy);
491
492  ObjCConstantStringType = QualType();
493
494  // void * type
495  VoidPtrTy = getPointerType(VoidTy);
496
497  // nullptr type (C++0x 2.14.7)
498  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
499
500  // half type (OpenCL 6.1.1.1) / ARM NEON __fp16
501  InitBuiltinType(HalfTy, BuiltinType::Half);
502}
503
504DiagnosticsEngine &ASTContext::getDiagnostics() const {
505  return SourceMgr.getDiagnostics();
506}
507
508AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
509  AttrVec *&Result = DeclAttrs[D];
510  if (!Result) {
511    void *Mem = Allocate(sizeof(AttrVec));
512    Result = new (Mem) AttrVec;
513  }
514
515  return *Result;
516}
517
518/// \brief Erase the attributes corresponding to the given declaration.
519void ASTContext::eraseDeclAttrs(const Decl *D) {
520  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
521  if (Pos != DeclAttrs.end()) {
522    Pos->second->~AttrVec();
523    DeclAttrs.erase(Pos);
524  }
525}
526
527MemberSpecializationInfo *
528ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
529  assert(Var->isStaticDataMember() && "Not a static data member");
530  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
531    = InstantiatedFromStaticDataMember.find(Var);
532  if (Pos == InstantiatedFromStaticDataMember.end())
533    return 0;
534
535  return Pos->second;
536}
537
538void
539ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
540                                                TemplateSpecializationKind TSK,
541                                          SourceLocation PointOfInstantiation) {
542  assert(Inst->isStaticDataMember() && "Not a static data member");
543  assert(Tmpl->isStaticDataMember() && "Not a static data member");
544  assert(!InstantiatedFromStaticDataMember[Inst] &&
545         "Already noted what static data member was instantiated from");
546  InstantiatedFromStaticDataMember[Inst]
547    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
548}
549
550FunctionDecl *ASTContext::getClassScopeSpecializationPattern(
551                                                     const FunctionDecl *FD){
552  assert(FD && "Specialization is 0");
553  llvm::DenseMap<const FunctionDecl*, FunctionDecl *>::const_iterator Pos
554    = ClassScopeSpecializationPattern.find(FD);
555  if (Pos == ClassScopeSpecializationPattern.end())
556    return 0;
557
558  return Pos->second;
559}
560
561void ASTContext::setClassScopeSpecializationPattern(FunctionDecl *FD,
562                                        FunctionDecl *Pattern) {
563  assert(FD && "Specialization is 0");
564  assert(Pattern && "Class scope specialization pattern is 0");
565  ClassScopeSpecializationPattern[FD] = Pattern;
566}
567
568NamedDecl *
569ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
570  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
571    = InstantiatedFromUsingDecl.find(UUD);
572  if (Pos == InstantiatedFromUsingDecl.end())
573    return 0;
574
575  return Pos->second;
576}
577
578void
579ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
580  assert((isa<UsingDecl>(Pattern) ||
581          isa<UnresolvedUsingValueDecl>(Pattern) ||
582          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
583         "pattern decl is not a using decl");
584  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
585  InstantiatedFromUsingDecl[Inst] = Pattern;
586}
587
588UsingShadowDecl *
589ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
590  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
591    = InstantiatedFromUsingShadowDecl.find(Inst);
592  if (Pos == InstantiatedFromUsingShadowDecl.end())
593    return 0;
594
595  return Pos->second;
596}
597
598void
599ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
600                                               UsingShadowDecl *Pattern) {
601  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
602  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
603}
604
605FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
606  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
607    = InstantiatedFromUnnamedFieldDecl.find(Field);
608  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
609    return 0;
610
611  return Pos->second;
612}
613
614void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
615                                                     FieldDecl *Tmpl) {
616  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
617  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
618  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
619         "Already noted what unnamed field was instantiated from");
620
621  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
622}
623
624bool ASTContext::ZeroBitfieldFollowsNonBitfield(const FieldDecl *FD,
625                                    const FieldDecl *LastFD) const {
626  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
627          FD->getBitWidthValue(*this) == 0);
628}
629
630bool ASTContext::ZeroBitfieldFollowsBitfield(const FieldDecl *FD,
631                                             const FieldDecl *LastFD) const {
632  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
633          FD->getBitWidthValue(*this) == 0 &&
634          LastFD->getBitWidthValue(*this) != 0);
635}
636
637bool ASTContext::BitfieldFollowsBitfield(const FieldDecl *FD,
638                                         const FieldDecl *LastFD) const {
639  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
640          FD->getBitWidthValue(*this) &&
641          LastFD->getBitWidthValue(*this));
642}
643
644bool ASTContext::NonBitfieldFollowsBitfield(const FieldDecl *FD,
645                                         const FieldDecl *LastFD) const {
646  return (!FD->isBitField() && LastFD && LastFD->isBitField() &&
647          LastFD->getBitWidthValue(*this));
648}
649
650bool ASTContext::BitfieldFollowsNonBitfield(const FieldDecl *FD,
651                                             const FieldDecl *LastFD) const {
652  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
653          FD->getBitWidthValue(*this));
654}
655
656ASTContext::overridden_cxx_method_iterator
657ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
658  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
659    = OverriddenMethods.find(Method);
660  if (Pos == OverriddenMethods.end())
661    return 0;
662
663  return Pos->second.begin();
664}
665
666ASTContext::overridden_cxx_method_iterator
667ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
668  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
669    = OverriddenMethods.find(Method);
670  if (Pos == OverriddenMethods.end())
671    return 0;
672
673  return Pos->second.end();
674}
675
676unsigned
677ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
678  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
679    = OverriddenMethods.find(Method);
680  if (Pos == OverriddenMethods.end())
681    return 0;
682
683  return Pos->second.size();
684}
685
686void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
687                                     const CXXMethodDecl *Overridden) {
688  OverriddenMethods[Method].push_back(Overridden);
689}
690
691void ASTContext::addedLocalImportDecl(ImportDecl *Import) {
692  assert(!Import->NextLocalImport && "Import declaration already in the chain");
693  assert(!Import->isFromASTFile() && "Non-local import declaration");
694  if (!FirstLocalImport) {
695    FirstLocalImport = Import;
696    LastLocalImport = Import;
697    return;
698  }
699
700  LastLocalImport->NextLocalImport = Import;
701  LastLocalImport = Import;
702}
703
704//===----------------------------------------------------------------------===//
705//                         Type Sizing and Analysis
706//===----------------------------------------------------------------------===//
707
708/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
709/// scalar floating point type.
710const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
711  const BuiltinType *BT = T->getAs<BuiltinType>();
712  assert(BT && "Not a floating point type!");
713  switch (BT->getKind()) {
714  default: llvm_unreachable("Not a floating point type!");
715  case BuiltinType::Half:       return Target->getHalfFormat();
716  case BuiltinType::Float:      return Target->getFloatFormat();
717  case BuiltinType::Double:     return Target->getDoubleFormat();
718  case BuiltinType::LongDouble: return Target->getLongDoubleFormat();
719  }
720}
721
722/// getDeclAlign - Return a conservative estimate of the alignment of the
723/// specified decl.  Note that bitfields do not have a valid alignment, so
724/// this method will assert on them.
725/// If @p RefAsPointee, references are treated like their underlying type
726/// (for alignof), else they're treated like pointers (for CodeGen).
727CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) const {
728  unsigned Align = Target->getCharWidth();
729
730  bool UseAlignAttrOnly = false;
731  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
732    Align = AlignFromAttr;
733
734    // __attribute__((aligned)) can increase or decrease alignment
735    // *except* on a struct or struct member, where it only increases
736    // alignment unless 'packed' is also specified.
737    //
738    // It is an error for alignas to decrease alignment, so we can
739    // ignore that possibility;  Sema should diagnose it.
740    if (isa<FieldDecl>(D)) {
741      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
742        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
743    } else {
744      UseAlignAttrOnly = true;
745    }
746  }
747  else if (isa<FieldDecl>(D))
748      UseAlignAttrOnly =
749        D->hasAttr<PackedAttr>() ||
750        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
751
752  // If we're using the align attribute only, just ignore everything
753  // else about the declaration and its type.
754  if (UseAlignAttrOnly) {
755    // do nothing
756
757  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
758    QualType T = VD->getType();
759    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
760      if (RefAsPointee)
761        T = RT->getPointeeType();
762      else
763        T = getPointerType(RT->getPointeeType());
764    }
765    if (!T->isIncompleteType() && !T->isFunctionType()) {
766      // Adjust alignments of declarations with array type by the
767      // large-array alignment on the target.
768      unsigned MinWidth = Target->getLargeArrayMinWidth();
769      const ArrayType *arrayType;
770      if (MinWidth && (arrayType = getAsArrayType(T))) {
771        if (isa<VariableArrayType>(arrayType))
772          Align = std::max(Align, Target->getLargeArrayAlign());
773        else if (isa<ConstantArrayType>(arrayType) &&
774                 MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
775          Align = std::max(Align, Target->getLargeArrayAlign());
776
777        // Walk through any array types while we're at it.
778        T = getBaseElementType(arrayType);
779      }
780      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
781    }
782
783    // Fields can be subject to extra alignment constraints, like if
784    // the field is packed, the struct is packed, or the struct has a
785    // a max-field-alignment constraint (#pragma pack).  So calculate
786    // the actual alignment of the field within the struct, and then
787    // (as we're expected to) constrain that by the alignment of the type.
788    if (const FieldDecl *field = dyn_cast<FieldDecl>(VD)) {
789      // So calculate the alignment of the field.
790      const ASTRecordLayout &layout = getASTRecordLayout(field->getParent());
791
792      // Start with the record's overall alignment.
793      unsigned fieldAlign = toBits(layout.getAlignment());
794
795      // Use the GCD of that and the offset within the record.
796      uint64_t offset = layout.getFieldOffset(field->getFieldIndex());
797      if (offset > 0) {
798        // Alignment is always a power of 2, so the GCD will be a power of 2,
799        // which means we get to do this crazy thing instead of Euclid's.
800        uint64_t lowBitOfOffset = offset & (~offset + 1);
801        if (lowBitOfOffset < fieldAlign)
802          fieldAlign = static_cast<unsigned>(lowBitOfOffset);
803      }
804
805      Align = std::min(Align, fieldAlign);
806    }
807  }
808
809  return toCharUnitsFromBits(Align);
810}
811
812std::pair<CharUnits, CharUnits>
813ASTContext::getTypeInfoInChars(const Type *T) const {
814  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
815  return std::make_pair(toCharUnitsFromBits(Info.first),
816                        toCharUnitsFromBits(Info.second));
817}
818
819std::pair<CharUnits, CharUnits>
820ASTContext::getTypeInfoInChars(QualType T) const {
821  return getTypeInfoInChars(T.getTypePtr());
822}
823
824std::pair<uint64_t, unsigned> ASTContext::getTypeInfo(const Type *T) const {
825  TypeInfoMap::iterator it = MemoizedTypeInfo.find(T);
826  if (it != MemoizedTypeInfo.end())
827    return it->second;
828
829  std::pair<uint64_t, unsigned> Info = getTypeInfoImpl(T);
830  MemoizedTypeInfo.insert(std::make_pair(T, Info));
831  return Info;
832}
833
834/// getTypeInfoImpl - Return the size of the specified type, in bits.  This
835/// method does not work on incomplete types.
836///
837/// FIXME: Pointers into different addr spaces could have different sizes and
838/// alignment requirements: getPointerInfo should take an AddrSpace, this
839/// should take a QualType, &c.
840std::pair<uint64_t, unsigned>
841ASTContext::getTypeInfoImpl(const Type *T) const {
842  uint64_t Width=0;
843  unsigned Align=8;
844  switch (T->getTypeClass()) {
845#define TYPE(Class, Base)
846#define ABSTRACT_TYPE(Class, Base)
847#define NON_CANONICAL_TYPE(Class, Base)
848#define DEPENDENT_TYPE(Class, Base) case Type::Class:
849#include "clang/AST/TypeNodes.def"
850    llvm_unreachable("Should not see dependent types");
851
852  case Type::FunctionNoProto:
853  case Type::FunctionProto:
854    // GCC extension: alignof(function) = 32 bits
855    Width = 0;
856    Align = 32;
857    break;
858
859  case Type::IncompleteArray:
860  case Type::VariableArray:
861    Width = 0;
862    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
863    break;
864
865  case Type::ConstantArray: {
866    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
867
868    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
869    uint64_t Size = CAT->getSize().getZExtValue();
870    assert((Size == 0 || EltInfo.first <= (uint64_t)(-1)/Size) &&
871           "Overflow in array type bit size evaluation");
872    Width = EltInfo.first*Size;
873    Align = EltInfo.second;
874    Width = llvm::RoundUpToAlignment(Width, Align);
875    break;
876  }
877  case Type::ExtVector:
878  case Type::Vector: {
879    const VectorType *VT = cast<VectorType>(T);
880    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
881    Width = EltInfo.first*VT->getNumElements();
882    Align = Width;
883    // If the alignment is not a power of 2, round up to the next power of 2.
884    // This happens for non-power-of-2 length vectors.
885    if (Align & (Align-1)) {
886      Align = llvm::NextPowerOf2(Align);
887      Width = llvm::RoundUpToAlignment(Width, Align);
888    }
889    break;
890  }
891
892  case Type::Builtin:
893    switch (cast<BuiltinType>(T)->getKind()) {
894    default: llvm_unreachable("Unknown builtin type!");
895    case BuiltinType::Void:
896      // GCC extension: alignof(void) = 8 bits.
897      Width = 0;
898      Align = 8;
899      break;
900
901    case BuiltinType::Bool:
902      Width = Target->getBoolWidth();
903      Align = Target->getBoolAlign();
904      break;
905    case BuiltinType::Char_S:
906    case BuiltinType::Char_U:
907    case BuiltinType::UChar:
908    case BuiltinType::SChar:
909      Width = Target->getCharWidth();
910      Align = Target->getCharAlign();
911      break;
912    case BuiltinType::WChar_S:
913    case BuiltinType::WChar_U:
914      Width = Target->getWCharWidth();
915      Align = Target->getWCharAlign();
916      break;
917    case BuiltinType::Char16:
918      Width = Target->getChar16Width();
919      Align = Target->getChar16Align();
920      break;
921    case BuiltinType::Char32:
922      Width = Target->getChar32Width();
923      Align = Target->getChar32Align();
924      break;
925    case BuiltinType::UShort:
926    case BuiltinType::Short:
927      Width = Target->getShortWidth();
928      Align = Target->getShortAlign();
929      break;
930    case BuiltinType::UInt:
931    case BuiltinType::Int:
932      Width = Target->getIntWidth();
933      Align = Target->getIntAlign();
934      break;
935    case BuiltinType::ULong:
936    case BuiltinType::Long:
937      Width = Target->getLongWidth();
938      Align = Target->getLongAlign();
939      break;
940    case BuiltinType::ULongLong:
941    case BuiltinType::LongLong:
942      Width = Target->getLongLongWidth();
943      Align = Target->getLongLongAlign();
944      break;
945    case BuiltinType::Int128:
946    case BuiltinType::UInt128:
947      Width = 128;
948      Align = 128; // int128_t is 128-bit aligned on all targets.
949      break;
950    case BuiltinType::Half:
951      Width = Target->getHalfWidth();
952      Align = Target->getHalfAlign();
953      break;
954    case BuiltinType::Float:
955      Width = Target->getFloatWidth();
956      Align = Target->getFloatAlign();
957      break;
958    case BuiltinType::Double:
959      Width = Target->getDoubleWidth();
960      Align = Target->getDoubleAlign();
961      break;
962    case BuiltinType::LongDouble:
963      Width = Target->getLongDoubleWidth();
964      Align = Target->getLongDoubleAlign();
965      break;
966    case BuiltinType::NullPtr:
967      Width = Target->getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
968      Align = Target->getPointerAlign(0); //   == sizeof(void*)
969      break;
970    case BuiltinType::ObjCId:
971    case BuiltinType::ObjCClass:
972    case BuiltinType::ObjCSel:
973      Width = Target->getPointerWidth(0);
974      Align = Target->getPointerAlign(0);
975      break;
976    }
977    break;
978  case Type::ObjCObjectPointer:
979    Width = Target->getPointerWidth(0);
980    Align = Target->getPointerAlign(0);
981    break;
982  case Type::BlockPointer: {
983    unsigned AS = getTargetAddressSpace(
984        cast<BlockPointerType>(T)->getPointeeType());
985    Width = Target->getPointerWidth(AS);
986    Align = Target->getPointerAlign(AS);
987    break;
988  }
989  case Type::LValueReference:
990  case Type::RValueReference: {
991    // alignof and sizeof should never enter this code path here, so we go
992    // the pointer route.
993    unsigned AS = getTargetAddressSpace(
994        cast<ReferenceType>(T)->getPointeeType());
995    Width = Target->getPointerWidth(AS);
996    Align = Target->getPointerAlign(AS);
997    break;
998  }
999  case Type::Pointer: {
1000    unsigned AS = getTargetAddressSpace(cast<PointerType>(T)->getPointeeType());
1001    Width = Target->getPointerWidth(AS);
1002    Align = Target->getPointerAlign(AS);
1003    break;
1004  }
1005  case Type::MemberPointer: {
1006    const MemberPointerType *MPT = cast<MemberPointerType>(T);
1007    std::pair<uint64_t, unsigned> PtrDiffInfo =
1008      getTypeInfo(getPointerDiffType());
1009    Width = PtrDiffInfo.first * ABI->getMemberPointerSize(MPT);
1010    Align = PtrDiffInfo.second;
1011    break;
1012  }
1013  case Type::Complex: {
1014    // Complex types have the same alignment as their elements, but twice the
1015    // size.
1016    std::pair<uint64_t, unsigned> EltInfo =
1017      getTypeInfo(cast<ComplexType>(T)->getElementType());
1018    Width = EltInfo.first*2;
1019    Align = EltInfo.second;
1020    break;
1021  }
1022  case Type::ObjCObject:
1023    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
1024  case Type::ObjCInterface: {
1025    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
1026    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
1027    Width = toBits(Layout.getSize());
1028    Align = toBits(Layout.getAlignment());
1029    break;
1030  }
1031  case Type::Record:
1032  case Type::Enum: {
1033    const TagType *TT = cast<TagType>(T);
1034
1035    if (TT->getDecl()->isInvalidDecl()) {
1036      Width = 8;
1037      Align = 8;
1038      break;
1039    }
1040
1041    if (const EnumType *ET = dyn_cast<EnumType>(TT))
1042      return getTypeInfo(ET->getDecl()->getIntegerType());
1043
1044    const RecordType *RT = cast<RecordType>(TT);
1045    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
1046    Width = toBits(Layout.getSize());
1047    Align = toBits(Layout.getAlignment());
1048    break;
1049  }
1050
1051  case Type::SubstTemplateTypeParm:
1052    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
1053                       getReplacementType().getTypePtr());
1054
1055  case Type::Auto: {
1056    const AutoType *A = cast<AutoType>(T);
1057    assert(A->isDeduced() && "Cannot request the size of a dependent type");
1058    return getTypeInfo(A->getDeducedType().getTypePtr());
1059  }
1060
1061  case Type::Paren:
1062    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
1063
1064  case Type::Typedef: {
1065    const TypedefNameDecl *Typedef = cast<TypedefType>(T)->getDecl();
1066    std::pair<uint64_t, unsigned> Info
1067      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
1068    // If the typedef has an aligned attribute on it, it overrides any computed
1069    // alignment we have.  This violates the GCC documentation (which says that
1070    // attribute(aligned) can only round up) but matches its implementation.
1071    if (unsigned AttrAlign = Typedef->getMaxAlignment())
1072      Align = AttrAlign;
1073    else
1074      Align = Info.second;
1075    Width = Info.first;
1076    break;
1077  }
1078
1079  case Type::TypeOfExpr:
1080    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
1081                         .getTypePtr());
1082
1083  case Type::TypeOf:
1084    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
1085
1086  case Type::Decltype:
1087    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
1088                        .getTypePtr());
1089
1090  case Type::UnaryTransform:
1091    return getTypeInfo(cast<UnaryTransformType>(T)->getUnderlyingType());
1092
1093  case Type::Elaborated:
1094    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
1095
1096  case Type::Attributed:
1097    return getTypeInfo(
1098                  cast<AttributedType>(T)->getEquivalentType().getTypePtr());
1099
1100  case Type::TemplateSpecialization: {
1101    assert(getCanonicalType(T) != T &&
1102           "Cannot request the size of a dependent type");
1103    const TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T);
1104    // A type alias template specialization may refer to a typedef with the
1105    // aligned attribute on it.
1106    if (TST->isTypeAlias())
1107      return getTypeInfo(TST->getAliasedType().getTypePtr());
1108    else
1109      return getTypeInfo(getCanonicalType(T));
1110  }
1111
1112  case Type::Atomic: {
1113    std::pair<uint64_t, unsigned> Info
1114      = getTypeInfo(cast<AtomicType>(T)->getValueType());
1115    Width = Info.first;
1116    Align = Info.second;
1117    if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth() &&
1118        llvm::isPowerOf2_64(Width)) {
1119      // We can potentially perform lock-free atomic operations for this
1120      // type; promote the alignment appropriately.
1121      // FIXME: We could potentially promote the width here as well...
1122      // is that worthwhile?  (Non-struct atomic types generally have
1123      // power-of-two size anyway, but structs might not.  Requires a bit
1124      // of implementation work to make sure we zero out the extra bits.)
1125      Align = static_cast<unsigned>(Width);
1126    }
1127  }
1128
1129  }
1130
1131  assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
1132  return std::make_pair(Width, Align);
1133}
1134
1135/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1136CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1137  return CharUnits::fromQuantity(BitSize / getCharWidth());
1138}
1139
1140/// toBits - Convert a size in characters to a size in characters.
1141int64_t ASTContext::toBits(CharUnits CharSize) const {
1142  return CharSize.getQuantity() * getCharWidth();
1143}
1144
1145/// getTypeSizeInChars - Return the size of the specified type, in characters.
1146/// This method does not work on incomplete types.
1147CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1148  return toCharUnitsFromBits(getTypeSize(T));
1149}
1150CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1151  return toCharUnitsFromBits(getTypeSize(T));
1152}
1153
1154/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1155/// characters. This method does not work on incomplete types.
1156CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1157  return toCharUnitsFromBits(getTypeAlign(T));
1158}
1159CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1160  return toCharUnitsFromBits(getTypeAlign(T));
1161}
1162
1163/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1164/// type for the current target in bits.  This can be different than the ABI
1165/// alignment in cases where it is beneficial for performance to overalign
1166/// a data type.
1167unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1168  unsigned ABIAlign = getTypeAlign(T);
1169
1170  // Double and long long should be naturally aligned if possible.
1171  if (const ComplexType* CT = T->getAs<ComplexType>())
1172    T = CT->getElementType().getTypePtr();
1173  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1174      T->isSpecificBuiltinType(BuiltinType::LongLong) ||
1175      T->isSpecificBuiltinType(BuiltinType::ULongLong))
1176    return std::max(ABIAlign, (unsigned)getTypeSize(T));
1177
1178  return ABIAlign;
1179}
1180
1181/// DeepCollectObjCIvars -
1182/// This routine first collects all declared, but not synthesized, ivars in
1183/// super class and then collects all ivars, including those synthesized for
1184/// current class. This routine is used for implementation of current class
1185/// when all ivars, declared and synthesized are known.
1186///
1187void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1188                                      bool leafClass,
1189                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1190  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1191    DeepCollectObjCIvars(SuperClass, false, Ivars);
1192  if (!leafClass) {
1193    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
1194         E = OI->ivar_end(); I != E; ++I)
1195      Ivars.push_back(&*I);
1196  } else {
1197    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1198    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1199         Iv= Iv->getNextIvar())
1200      Ivars.push_back(Iv);
1201  }
1202}
1203
1204/// CollectInheritedProtocols - Collect all protocols in current class and
1205/// those inherited by it.
1206void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1207                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1208  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1209    // We can use protocol_iterator here instead of
1210    // all_referenced_protocol_iterator since we are walking all categories.
1211    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
1212         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
1213      ObjCProtocolDecl *Proto = (*P);
1214      Protocols.insert(Proto->getCanonicalDecl());
1215      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1216           PE = Proto->protocol_end(); P != PE; ++P) {
1217        Protocols.insert((*P)->getCanonicalDecl());
1218        CollectInheritedProtocols(*P, Protocols);
1219      }
1220    }
1221
1222    // Categories of this Interface.
1223    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
1224         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
1225      CollectInheritedProtocols(CDeclChain, Protocols);
1226    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1227      while (SD) {
1228        CollectInheritedProtocols(SD, Protocols);
1229        SD = SD->getSuperClass();
1230      }
1231  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1232    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
1233         PE = OC->protocol_end(); P != PE; ++P) {
1234      ObjCProtocolDecl *Proto = (*P);
1235      Protocols.insert(Proto->getCanonicalDecl());
1236      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1237           PE = Proto->protocol_end(); P != PE; ++P)
1238        CollectInheritedProtocols(*P, Protocols);
1239    }
1240  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
1241    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
1242         PE = OP->protocol_end(); P != PE; ++P) {
1243      ObjCProtocolDecl *Proto = (*P);
1244      Protocols.insert(Proto->getCanonicalDecl());
1245      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1246           PE = Proto->protocol_end(); P != PE; ++P)
1247        CollectInheritedProtocols(*P, Protocols);
1248    }
1249  }
1250}
1251
1252unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
1253  unsigned count = 0;
1254  // Count ivars declared in class extension.
1255  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
1256       CDecl = CDecl->getNextClassExtension())
1257    count += CDecl->ivar_size();
1258
1259  // Count ivar defined in this class's implementation.  This
1260  // includes synthesized ivars.
1261  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
1262    count += ImplDecl->ivar_size();
1263
1264  return count;
1265}
1266
1267bool ASTContext::isSentinelNullExpr(const Expr *E) {
1268  if (!E)
1269    return false;
1270
1271  // nullptr_t is always treated as null.
1272  if (E->getType()->isNullPtrType()) return true;
1273
1274  if (E->getType()->isAnyPointerType() &&
1275      E->IgnoreParenCasts()->isNullPointerConstant(*this,
1276                                                Expr::NPC_ValueDependentIsNull))
1277    return true;
1278
1279  // Unfortunately, __null has type 'int'.
1280  if (isa<GNUNullExpr>(E)) return true;
1281
1282  return false;
1283}
1284
1285/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
1286ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
1287  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1288    I = ObjCImpls.find(D);
1289  if (I != ObjCImpls.end())
1290    return cast<ObjCImplementationDecl>(I->second);
1291  return 0;
1292}
1293/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
1294ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
1295  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1296    I = ObjCImpls.find(D);
1297  if (I != ObjCImpls.end())
1298    return cast<ObjCCategoryImplDecl>(I->second);
1299  return 0;
1300}
1301
1302/// \brief Set the implementation of ObjCInterfaceDecl.
1303void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1304                           ObjCImplementationDecl *ImplD) {
1305  assert(IFaceD && ImplD && "Passed null params");
1306  ObjCImpls[IFaceD] = ImplD;
1307}
1308/// \brief Set the implementation of ObjCCategoryDecl.
1309void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1310                           ObjCCategoryImplDecl *ImplD) {
1311  assert(CatD && ImplD && "Passed null params");
1312  ObjCImpls[CatD] = ImplD;
1313}
1314
1315ObjCInterfaceDecl *ASTContext::getObjContainingInterface(NamedDecl *ND) const {
1316  if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(ND->getDeclContext()))
1317    return ID;
1318  if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(ND->getDeclContext()))
1319    return CD->getClassInterface();
1320  if (ObjCImplDecl *IMD = dyn_cast<ObjCImplDecl>(ND->getDeclContext()))
1321    return IMD->getClassInterface();
1322
1323  return 0;
1324}
1325
1326/// \brief Get the copy initialization expression of VarDecl,or NULL if
1327/// none exists.
1328Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
1329  assert(VD && "Passed null params");
1330  assert(VD->hasAttr<BlocksAttr>() &&
1331         "getBlockVarCopyInits - not __block var");
1332  llvm::DenseMap<const VarDecl*, Expr*>::iterator
1333    I = BlockVarCopyInits.find(VD);
1334  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : 0;
1335}
1336
1337/// \brief Set the copy inialization expression of a block var decl.
1338void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
1339  assert(VD && Init && "Passed null params");
1340  assert(VD->hasAttr<BlocksAttr>() &&
1341         "setBlockVarCopyInits - not __block var");
1342  BlockVarCopyInits[VD] = Init;
1343}
1344
1345/// \brief Allocate an uninitialized TypeSourceInfo.
1346///
1347/// The caller should initialize the memory held by TypeSourceInfo using
1348/// the TypeLoc wrappers.
1349///
1350/// \param T the type that will be the basis for type source info. This type
1351/// should refer to how the declarator was written in source code, not to
1352/// what type semantic analysis resolved the declarator to.
1353TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1354                                                 unsigned DataSize) const {
1355  if (!DataSize)
1356    DataSize = TypeLoc::getFullDataSizeForType(T);
1357  else
1358    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1359           "incorrect data size provided to CreateTypeSourceInfo!");
1360
1361  TypeSourceInfo *TInfo =
1362    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1363  new (TInfo) TypeSourceInfo(T);
1364  return TInfo;
1365}
1366
1367TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1368                                                     SourceLocation L) const {
1369  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1370  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
1371  return DI;
1372}
1373
1374const ASTRecordLayout &
1375ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
1376  return getObjCLayout(D, 0);
1377}
1378
1379const ASTRecordLayout &
1380ASTContext::getASTObjCImplementationLayout(
1381                                        const ObjCImplementationDecl *D) const {
1382  return getObjCLayout(D->getClassInterface(), D);
1383}
1384
1385//===----------------------------------------------------------------------===//
1386//                   Type creation/memoization methods
1387//===----------------------------------------------------------------------===//
1388
1389QualType
1390ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
1391  unsigned fastQuals = quals.getFastQualifiers();
1392  quals.removeFastQualifiers();
1393
1394  // Check if we've already instantiated this type.
1395  llvm::FoldingSetNodeID ID;
1396  ExtQuals::Profile(ID, baseType, quals);
1397  void *insertPos = 0;
1398  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
1399    assert(eq->getQualifiers() == quals);
1400    return QualType(eq, fastQuals);
1401  }
1402
1403  // If the base type is not canonical, make the appropriate canonical type.
1404  QualType canon;
1405  if (!baseType->isCanonicalUnqualified()) {
1406    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
1407    canonSplit.Quals.addConsistentQualifiers(quals);
1408    canon = getExtQualType(canonSplit.Ty, canonSplit.Quals);
1409
1410    // Re-find the insert position.
1411    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
1412  }
1413
1414  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
1415  ExtQualNodes.InsertNode(eq, insertPos);
1416  return QualType(eq, fastQuals);
1417}
1418
1419QualType
1420ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
1421  QualType CanT = getCanonicalType(T);
1422  if (CanT.getAddressSpace() == AddressSpace)
1423    return T;
1424
1425  // If we are composing extended qualifiers together, merge together
1426  // into one ExtQuals node.
1427  QualifierCollector Quals;
1428  const Type *TypeNode = Quals.strip(T);
1429
1430  // If this type already has an address space specified, it cannot get
1431  // another one.
1432  assert(!Quals.hasAddressSpace() &&
1433         "Type cannot be in multiple addr spaces!");
1434  Quals.addAddressSpace(AddressSpace);
1435
1436  return getExtQualType(TypeNode, Quals);
1437}
1438
1439QualType ASTContext::getObjCGCQualType(QualType T,
1440                                       Qualifiers::GC GCAttr) const {
1441  QualType CanT = getCanonicalType(T);
1442  if (CanT.getObjCGCAttr() == GCAttr)
1443    return T;
1444
1445  if (const PointerType *ptr = T->getAs<PointerType>()) {
1446    QualType Pointee = ptr->getPointeeType();
1447    if (Pointee->isAnyPointerType()) {
1448      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1449      return getPointerType(ResultType);
1450    }
1451  }
1452
1453  // If we are composing extended qualifiers together, merge together
1454  // into one ExtQuals node.
1455  QualifierCollector Quals;
1456  const Type *TypeNode = Quals.strip(T);
1457
1458  // If this type already has an ObjCGC specified, it cannot get
1459  // another one.
1460  assert(!Quals.hasObjCGCAttr() &&
1461         "Type cannot have multiple ObjCGCs!");
1462  Quals.addObjCGCAttr(GCAttr);
1463
1464  return getExtQualType(TypeNode, Quals);
1465}
1466
1467const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
1468                                                   FunctionType::ExtInfo Info) {
1469  if (T->getExtInfo() == Info)
1470    return T;
1471
1472  QualType Result;
1473  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
1474    Result = getFunctionNoProtoType(FNPT->getResultType(), Info);
1475  } else {
1476    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
1477    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
1478    EPI.ExtInfo = Info;
1479    Result = getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1480                             FPT->getNumArgs(), EPI);
1481  }
1482
1483  return cast<FunctionType>(Result.getTypePtr());
1484}
1485
1486/// getComplexType - Return the uniqued reference to the type for a complex
1487/// number with the specified element type.
1488QualType ASTContext::getComplexType(QualType T) const {
1489  // Unique pointers, to guarantee there is only one pointer of a particular
1490  // structure.
1491  llvm::FoldingSetNodeID ID;
1492  ComplexType::Profile(ID, T);
1493
1494  void *InsertPos = 0;
1495  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1496    return QualType(CT, 0);
1497
1498  // If the pointee type isn't canonical, this won't be a canonical type either,
1499  // so fill in the canonical type field.
1500  QualType Canonical;
1501  if (!T.isCanonical()) {
1502    Canonical = getComplexType(getCanonicalType(T));
1503
1504    // Get the new insert position for the node we care about.
1505    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1506    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1507  }
1508  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1509  Types.push_back(New);
1510  ComplexTypes.InsertNode(New, InsertPos);
1511  return QualType(New, 0);
1512}
1513
1514/// getPointerType - Return the uniqued reference to the type for a pointer to
1515/// the specified type.
1516QualType ASTContext::getPointerType(QualType T) const {
1517  // Unique pointers, to guarantee there is only one pointer of a particular
1518  // structure.
1519  llvm::FoldingSetNodeID ID;
1520  PointerType::Profile(ID, T);
1521
1522  void *InsertPos = 0;
1523  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1524    return QualType(PT, 0);
1525
1526  // If the pointee type isn't canonical, this won't be a canonical type either,
1527  // so fill in the canonical type field.
1528  QualType Canonical;
1529  if (!T.isCanonical()) {
1530    Canonical = getPointerType(getCanonicalType(T));
1531
1532    // Get the new insert position for the node we care about.
1533    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1534    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1535  }
1536  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1537  Types.push_back(New);
1538  PointerTypes.InsertNode(New, InsertPos);
1539  return QualType(New, 0);
1540}
1541
1542/// getBlockPointerType - Return the uniqued reference to the type for
1543/// a pointer to the specified block.
1544QualType ASTContext::getBlockPointerType(QualType T) const {
1545  assert(T->isFunctionType() && "block of function types only");
1546  // Unique pointers, to guarantee there is only one block of a particular
1547  // structure.
1548  llvm::FoldingSetNodeID ID;
1549  BlockPointerType::Profile(ID, T);
1550
1551  void *InsertPos = 0;
1552  if (BlockPointerType *PT =
1553        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1554    return QualType(PT, 0);
1555
1556  // If the block pointee type isn't canonical, this won't be a canonical
1557  // type either so fill in the canonical type field.
1558  QualType Canonical;
1559  if (!T.isCanonical()) {
1560    Canonical = getBlockPointerType(getCanonicalType(T));
1561
1562    // Get the new insert position for the node we care about.
1563    BlockPointerType *NewIP =
1564      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1565    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1566  }
1567  BlockPointerType *New
1568    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1569  Types.push_back(New);
1570  BlockPointerTypes.InsertNode(New, InsertPos);
1571  return QualType(New, 0);
1572}
1573
1574/// getLValueReferenceType - Return the uniqued reference to the type for an
1575/// lvalue reference to the specified type.
1576QualType
1577ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
1578  assert(getCanonicalType(T) != OverloadTy &&
1579         "Unresolved overloaded function type");
1580
1581  // Unique pointers, to guarantee there is only one pointer of a particular
1582  // structure.
1583  llvm::FoldingSetNodeID ID;
1584  ReferenceType::Profile(ID, T, SpelledAsLValue);
1585
1586  void *InsertPos = 0;
1587  if (LValueReferenceType *RT =
1588        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1589    return QualType(RT, 0);
1590
1591  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1592
1593  // If the referencee type isn't canonical, this won't be a canonical type
1594  // either, so fill in the canonical type field.
1595  QualType Canonical;
1596  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1597    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1598    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1599
1600    // Get the new insert position for the node we care about.
1601    LValueReferenceType *NewIP =
1602      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1603    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1604  }
1605
1606  LValueReferenceType *New
1607    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1608                                                     SpelledAsLValue);
1609  Types.push_back(New);
1610  LValueReferenceTypes.InsertNode(New, InsertPos);
1611
1612  return QualType(New, 0);
1613}
1614
1615/// getRValueReferenceType - Return the uniqued reference to the type for an
1616/// rvalue reference to the specified type.
1617QualType ASTContext::getRValueReferenceType(QualType T) const {
1618  // Unique pointers, to guarantee there is only one pointer of a particular
1619  // structure.
1620  llvm::FoldingSetNodeID ID;
1621  ReferenceType::Profile(ID, T, false);
1622
1623  void *InsertPos = 0;
1624  if (RValueReferenceType *RT =
1625        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1626    return QualType(RT, 0);
1627
1628  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1629
1630  // If the referencee type isn't canonical, this won't be a canonical type
1631  // either, so fill in the canonical type field.
1632  QualType Canonical;
1633  if (InnerRef || !T.isCanonical()) {
1634    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1635    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1636
1637    // Get the new insert position for the node we care about.
1638    RValueReferenceType *NewIP =
1639      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1640    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1641  }
1642
1643  RValueReferenceType *New
1644    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1645  Types.push_back(New);
1646  RValueReferenceTypes.InsertNode(New, InsertPos);
1647  return QualType(New, 0);
1648}
1649
1650/// getMemberPointerType - Return the uniqued reference to the type for a
1651/// member pointer to the specified type, in the specified class.
1652QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
1653  // Unique pointers, to guarantee there is only one pointer of a particular
1654  // structure.
1655  llvm::FoldingSetNodeID ID;
1656  MemberPointerType::Profile(ID, T, Cls);
1657
1658  void *InsertPos = 0;
1659  if (MemberPointerType *PT =
1660      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1661    return QualType(PT, 0);
1662
1663  // If the pointee or class type isn't canonical, this won't be a canonical
1664  // type either, so fill in the canonical type field.
1665  QualType Canonical;
1666  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1667    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1668
1669    // Get the new insert position for the node we care about.
1670    MemberPointerType *NewIP =
1671      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1672    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1673  }
1674  MemberPointerType *New
1675    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1676  Types.push_back(New);
1677  MemberPointerTypes.InsertNode(New, InsertPos);
1678  return QualType(New, 0);
1679}
1680
1681/// getConstantArrayType - Return the unique reference to the type for an
1682/// array of the specified element type.
1683QualType ASTContext::getConstantArrayType(QualType EltTy,
1684                                          const llvm::APInt &ArySizeIn,
1685                                          ArrayType::ArraySizeModifier ASM,
1686                                          unsigned IndexTypeQuals) const {
1687  assert((EltTy->isDependentType() ||
1688          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1689         "Constant array of VLAs is illegal!");
1690
1691  // Convert the array size into a canonical width matching the pointer size for
1692  // the target.
1693  llvm::APInt ArySize(ArySizeIn);
1694  ArySize =
1695    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
1696
1697  llvm::FoldingSetNodeID ID;
1698  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
1699
1700  void *InsertPos = 0;
1701  if (ConstantArrayType *ATP =
1702      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1703    return QualType(ATP, 0);
1704
1705  // If the element type isn't canonical or has qualifiers, this won't
1706  // be a canonical type either, so fill in the canonical type field.
1707  QualType Canon;
1708  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1709    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1710    Canon = getConstantArrayType(QualType(canonSplit.Ty, 0), ArySize,
1711                                 ASM, IndexTypeQuals);
1712    Canon = getQualifiedType(Canon, canonSplit.Quals);
1713
1714    // Get the new insert position for the node we care about.
1715    ConstantArrayType *NewIP =
1716      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1717    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1718  }
1719
1720  ConstantArrayType *New = new(*this,TypeAlignment)
1721    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
1722  ConstantArrayTypes.InsertNode(New, InsertPos);
1723  Types.push_back(New);
1724  return QualType(New, 0);
1725}
1726
1727/// getVariableArrayDecayedType - Turns the given type, which may be
1728/// variably-modified, into the corresponding type with all the known
1729/// sizes replaced with [*].
1730QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
1731  // Vastly most common case.
1732  if (!type->isVariablyModifiedType()) return type;
1733
1734  QualType result;
1735
1736  SplitQualType split = type.getSplitDesugaredType();
1737  const Type *ty = split.Ty;
1738  switch (ty->getTypeClass()) {
1739#define TYPE(Class, Base)
1740#define ABSTRACT_TYPE(Class, Base)
1741#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
1742#include "clang/AST/TypeNodes.def"
1743    llvm_unreachable("didn't desugar past all non-canonical types?");
1744
1745  // These types should never be variably-modified.
1746  case Type::Builtin:
1747  case Type::Complex:
1748  case Type::Vector:
1749  case Type::ExtVector:
1750  case Type::DependentSizedExtVector:
1751  case Type::ObjCObject:
1752  case Type::ObjCInterface:
1753  case Type::ObjCObjectPointer:
1754  case Type::Record:
1755  case Type::Enum:
1756  case Type::UnresolvedUsing:
1757  case Type::TypeOfExpr:
1758  case Type::TypeOf:
1759  case Type::Decltype:
1760  case Type::UnaryTransform:
1761  case Type::DependentName:
1762  case Type::InjectedClassName:
1763  case Type::TemplateSpecialization:
1764  case Type::DependentTemplateSpecialization:
1765  case Type::TemplateTypeParm:
1766  case Type::SubstTemplateTypeParmPack:
1767  case Type::Auto:
1768  case Type::PackExpansion:
1769    llvm_unreachable("type should never be variably-modified");
1770
1771  // These types can be variably-modified but should never need to
1772  // further decay.
1773  case Type::FunctionNoProto:
1774  case Type::FunctionProto:
1775  case Type::BlockPointer:
1776  case Type::MemberPointer:
1777    return type;
1778
1779  // These types can be variably-modified.  All these modifications
1780  // preserve structure except as noted by comments.
1781  // TODO: if we ever care about optimizing VLAs, there are no-op
1782  // optimizations available here.
1783  case Type::Pointer:
1784    result = getPointerType(getVariableArrayDecayedType(
1785                              cast<PointerType>(ty)->getPointeeType()));
1786    break;
1787
1788  case Type::LValueReference: {
1789    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
1790    result = getLValueReferenceType(
1791                 getVariableArrayDecayedType(lv->getPointeeType()),
1792                                    lv->isSpelledAsLValue());
1793    break;
1794  }
1795
1796  case Type::RValueReference: {
1797    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
1798    result = getRValueReferenceType(
1799                 getVariableArrayDecayedType(lv->getPointeeType()));
1800    break;
1801  }
1802
1803  case Type::Atomic: {
1804    const AtomicType *at = cast<AtomicType>(ty);
1805    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
1806    break;
1807  }
1808
1809  case Type::ConstantArray: {
1810    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
1811    result = getConstantArrayType(
1812                 getVariableArrayDecayedType(cat->getElementType()),
1813                                  cat->getSize(),
1814                                  cat->getSizeModifier(),
1815                                  cat->getIndexTypeCVRQualifiers());
1816    break;
1817  }
1818
1819  case Type::DependentSizedArray: {
1820    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
1821    result = getDependentSizedArrayType(
1822                 getVariableArrayDecayedType(dat->getElementType()),
1823                                        dat->getSizeExpr(),
1824                                        dat->getSizeModifier(),
1825                                        dat->getIndexTypeCVRQualifiers(),
1826                                        dat->getBracketsRange());
1827    break;
1828  }
1829
1830  // Turn incomplete types into [*] types.
1831  case Type::IncompleteArray: {
1832    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
1833    result = getVariableArrayType(
1834                 getVariableArrayDecayedType(iat->getElementType()),
1835                                  /*size*/ 0,
1836                                  ArrayType::Normal,
1837                                  iat->getIndexTypeCVRQualifiers(),
1838                                  SourceRange());
1839    break;
1840  }
1841
1842  // Turn VLA types into [*] types.
1843  case Type::VariableArray: {
1844    const VariableArrayType *vat = cast<VariableArrayType>(ty);
1845    result = getVariableArrayType(
1846                 getVariableArrayDecayedType(vat->getElementType()),
1847                                  /*size*/ 0,
1848                                  ArrayType::Star,
1849                                  vat->getIndexTypeCVRQualifiers(),
1850                                  vat->getBracketsRange());
1851    break;
1852  }
1853  }
1854
1855  // Apply the top-level qualifiers from the original.
1856  return getQualifiedType(result, split.Quals);
1857}
1858
1859/// getVariableArrayType - Returns a non-unique reference to the type for a
1860/// variable array of the specified element type.
1861QualType ASTContext::getVariableArrayType(QualType EltTy,
1862                                          Expr *NumElts,
1863                                          ArrayType::ArraySizeModifier ASM,
1864                                          unsigned IndexTypeQuals,
1865                                          SourceRange Brackets) const {
1866  // Since we don't unique expressions, it isn't possible to unique VLA's
1867  // that have an expression provided for their size.
1868  QualType Canon;
1869
1870  // Be sure to pull qualifiers off the element type.
1871  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1872    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1873    Canon = getVariableArrayType(QualType(canonSplit.Ty, 0), NumElts, ASM,
1874                                 IndexTypeQuals, Brackets);
1875    Canon = getQualifiedType(Canon, canonSplit.Quals);
1876  }
1877
1878  VariableArrayType *New = new(*this, TypeAlignment)
1879    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
1880
1881  VariableArrayTypes.push_back(New);
1882  Types.push_back(New);
1883  return QualType(New, 0);
1884}
1885
1886/// getDependentSizedArrayType - Returns a non-unique reference to
1887/// the type for a dependently-sized array of the specified element
1888/// type.
1889QualType ASTContext::getDependentSizedArrayType(QualType elementType,
1890                                                Expr *numElements,
1891                                                ArrayType::ArraySizeModifier ASM,
1892                                                unsigned elementTypeQuals,
1893                                                SourceRange brackets) const {
1894  assert((!numElements || numElements->isTypeDependent() ||
1895          numElements->isValueDependent()) &&
1896         "Size must be type- or value-dependent!");
1897
1898  // Dependently-sized array types that do not have a specified number
1899  // of elements will have their sizes deduced from a dependent
1900  // initializer.  We do no canonicalization here at all, which is okay
1901  // because they can't be used in most locations.
1902  if (!numElements) {
1903    DependentSizedArrayType *newType
1904      = new (*this, TypeAlignment)
1905          DependentSizedArrayType(*this, elementType, QualType(),
1906                                  numElements, ASM, elementTypeQuals,
1907                                  brackets);
1908    Types.push_back(newType);
1909    return QualType(newType, 0);
1910  }
1911
1912  // Otherwise, we actually build a new type every time, but we
1913  // also build a canonical type.
1914
1915  SplitQualType canonElementType = getCanonicalType(elementType).split();
1916
1917  void *insertPos = 0;
1918  llvm::FoldingSetNodeID ID;
1919  DependentSizedArrayType::Profile(ID, *this,
1920                                   QualType(canonElementType.Ty, 0),
1921                                   ASM, elementTypeQuals, numElements);
1922
1923  // Look for an existing type with these properties.
1924  DependentSizedArrayType *canonTy =
1925    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1926
1927  // If we don't have one, build one.
1928  if (!canonTy) {
1929    canonTy = new (*this, TypeAlignment)
1930      DependentSizedArrayType(*this, QualType(canonElementType.Ty, 0),
1931                              QualType(), numElements, ASM, elementTypeQuals,
1932                              brackets);
1933    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
1934    Types.push_back(canonTy);
1935  }
1936
1937  // Apply qualifiers from the element type to the array.
1938  QualType canon = getQualifiedType(QualType(canonTy,0),
1939                                    canonElementType.Quals);
1940
1941  // If we didn't need extra canonicalization for the element type,
1942  // then just use that as our result.
1943  if (QualType(canonElementType.Ty, 0) == elementType)
1944    return canon;
1945
1946  // Otherwise, we need to build a type which follows the spelling
1947  // of the element type.
1948  DependentSizedArrayType *sugaredType
1949    = new (*this, TypeAlignment)
1950        DependentSizedArrayType(*this, elementType, canon, numElements,
1951                                ASM, elementTypeQuals, brackets);
1952  Types.push_back(sugaredType);
1953  return QualType(sugaredType, 0);
1954}
1955
1956QualType ASTContext::getIncompleteArrayType(QualType elementType,
1957                                            ArrayType::ArraySizeModifier ASM,
1958                                            unsigned elementTypeQuals) const {
1959  llvm::FoldingSetNodeID ID;
1960  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
1961
1962  void *insertPos = 0;
1963  if (IncompleteArrayType *iat =
1964       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
1965    return QualType(iat, 0);
1966
1967  // If the element type isn't canonical, this won't be a canonical type
1968  // either, so fill in the canonical type field.  We also have to pull
1969  // qualifiers off the element type.
1970  QualType canon;
1971
1972  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
1973    SplitQualType canonSplit = getCanonicalType(elementType).split();
1974    canon = getIncompleteArrayType(QualType(canonSplit.Ty, 0),
1975                                   ASM, elementTypeQuals);
1976    canon = getQualifiedType(canon, canonSplit.Quals);
1977
1978    // Get the new insert position for the node we care about.
1979    IncompleteArrayType *existing =
1980      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1981    assert(!existing && "Shouldn't be in the map!"); (void) existing;
1982  }
1983
1984  IncompleteArrayType *newType = new (*this, TypeAlignment)
1985    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
1986
1987  IncompleteArrayTypes.InsertNode(newType, insertPos);
1988  Types.push_back(newType);
1989  return QualType(newType, 0);
1990}
1991
1992/// getVectorType - Return the unique reference to a vector type of
1993/// the specified element type and size. VectorType must be a built-in type.
1994QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1995                                   VectorType::VectorKind VecKind) const {
1996  assert(vecType->isBuiltinType());
1997
1998  // Check if we've already instantiated a vector of this type.
1999  llvm::FoldingSetNodeID ID;
2000  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
2001
2002  void *InsertPos = 0;
2003  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2004    return QualType(VTP, 0);
2005
2006  // If the element type isn't canonical, this won't be a canonical type either,
2007  // so fill in the canonical type field.
2008  QualType Canonical;
2009  if (!vecType.isCanonical()) {
2010    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
2011
2012    // Get the new insert position for the node we care about.
2013    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2014    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2015  }
2016  VectorType *New = new (*this, TypeAlignment)
2017    VectorType(vecType, NumElts, Canonical, VecKind);
2018  VectorTypes.InsertNode(New, InsertPos);
2019  Types.push_back(New);
2020  return QualType(New, 0);
2021}
2022
2023/// getExtVectorType - Return the unique reference to an extended vector type of
2024/// the specified element type and size. VectorType must be a built-in type.
2025QualType
2026ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
2027  assert(vecType->isBuiltinType() || vecType->isDependentType());
2028
2029  // Check if we've already instantiated a vector of this type.
2030  llvm::FoldingSetNodeID ID;
2031  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
2032                      VectorType::GenericVector);
2033  void *InsertPos = 0;
2034  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2035    return QualType(VTP, 0);
2036
2037  // If the element type isn't canonical, this won't be a canonical type either,
2038  // so fill in the canonical type field.
2039  QualType Canonical;
2040  if (!vecType.isCanonical()) {
2041    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
2042
2043    // Get the new insert position for the node we care about.
2044    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2045    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2046  }
2047  ExtVectorType *New = new (*this, TypeAlignment)
2048    ExtVectorType(vecType, NumElts, Canonical);
2049  VectorTypes.InsertNode(New, InsertPos);
2050  Types.push_back(New);
2051  return QualType(New, 0);
2052}
2053
2054QualType
2055ASTContext::getDependentSizedExtVectorType(QualType vecType,
2056                                           Expr *SizeExpr,
2057                                           SourceLocation AttrLoc) const {
2058  llvm::FoldingSetNodeID ID;
2059  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
2060                                       SizeExpr);
2061
2062  void *InsertPos = 0;
2063  DependentSizedExtVectorType *Canon
2064    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2065  DependentSizedExtVectorType *New;
2066  if (Canon) {
2067    // We already have a canonical version of this array type; use it as
2068    // the canonical type for a newly-built type.
2069    New = new (*this, TypeAlignment)
2070      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
2071                                  SizeExpr, AttrLoc);
2072  } else {
2073    QualType CanonVecTy = getCanonicalType(vecType);
2074    if (CanonVecTy == vecType) {
2075      New = new (*this, TypeAlignment)
2076        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
2077                                    AttrLoc);
2078
2079      DependentSizedExtVectorType *CanonCheck
2080        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2081      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
2082      (void)CanonCheck;
2083      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
2084    } else {
2085      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
2086                                                      SourceLocation());
2087      New = new (*this, TypeAlignment)
2088        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2089    }
2090  }
2091
2092  Types.push_back(New);
2093  return QualType(New, 0);
2094}
2095
2096/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
2097///
2098QualType
2099ASTContext::getFunctionNoProtoType(QualType ResultTy,
2100                                   const FunctionType::ExtInfo &Info) const {
2101  const CallingConv DefaultCC = Info.getCC();
2102  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2103                               CC_X86StdCall : DefaultCC;
2104  // Unique functions, to guarantee there is only one function of a particular
2105  // structure.
2106  llvm::FoldingSetNodeID ID;
2107  FunctionNoProtoType::Profile(ID, ResultTy, Info);
2108
2109  void *InsertPos = 0;
2110  if (FunctionNoProtoType *FT =
2111        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2112    return QualType(FT, 0);
2113
2114  QualType Canonical;
2115  if (!ResultTy.isCanonical() ||
2116      getCanonicalCallConv(CallConv) != CallConv) {
2117    Canonical =
2118      getFunctionNoProtoType(getCanonicalType(ResultTy),
2119                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
2120
2121    // Get the new insert position for the node we care about.
2122    FunctionNoProtoType *NewIP =
2123      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2124    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2125  }
2126
2127  FunctionProtoType::ExtInfo newInfo = Info.withCallingConv(CallConv);
2128  FunctionNoProtoType *New = new (*this, TypeAlignment)
2129    FunctionNoProtoType(ResultTy, Canonical, newInfo);
2130  Types.push_back(New);
2131  FunctionNoProtoTypes.InsertNode(New, InsertPos);
2132  return QualType(New, 0);
2133}
2134
2135/// getFunctionType - Return a normal function type with a typed argument
2136/// list.  isVariadic indicates whether the argument list includes '...'.
2137QualType
2138ASTContext::getFunctionType(QualType ResultTy,
2139                            const QualType *ArgArray, unsigned NumArgs,
2140                            const FunctionProtoType::ExtProtoInfo &EPI) const {
2141  // Unique functions, to guarantee there is only one function of a particular
2142  // structure.
2143  llvm::FoldingSetNodeID ID;
2144  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, EPI, *this);
2145
2146  void *InsertPos = 0;
2147  if (FunctionProtoType *FTP =
2148        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2149    return QualType(FTP, 0);
2150
2151  // Determine whether the type being created is already canonical or not.
2152  bool isCanonical =
2153    EPI.ExceptionSpecType == EST_None && ResultTy.isCanonical() &&
2154    !EPI.HasTrailingReturn;
2155  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
2156    if (!ArgArray[i].isCanonicalAsParam())
2157      isCanonical = false;
2158
2159  const CallingConv DefaultCC = EPI.ExtInfo.getCC();
2160  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2161                               CC_X86StdCall : DefaultCC;
2162
2163  // If this type isn't canonical, get the canonical version of it.
2164  // The exception spec is not part of the canonical type.
2165  QualType Canonical;
2166  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
2167    SmallVector<QualType, 16> CanonicalArgs;
2168    CanonicalArgs.reserve(NumArgs);
2169    for (unsigned i = 0; i != NumArgs; ++i)
2170      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
2171
2172    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
2173    CanonicalEPI.HasTrailingReturn = false;
2174    CanonicalEPI.ExceptionSpecType = EST_None;
2175    CanonicalEPI.NumExceptions = 0;
2176    CanonicalEPI.ExtInfo
2177      = CanonicalEPI.ExtInfo.withCallingConv(getCanonicalCallConv(CallConv));
2178
2179    Canonical = getFunctionType(getCanonicalType(ResultTy),
2180                                CanonicalArgs.data(), NumArgs,
2181                                CanonicalEPI);
2182
2183    // Get the new insert position for the node we care about.
2184    FunctionProtoType *NewIP =
2185      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2186    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2187  }
2188
2189  // FunctionProtoType objects are allocated with extra bytes after
2190  // them for three variable size arrays at the end:
2191  //  - parameter types
2192  //  - exception types
2193  //  - consumed-arguments flags
2194  // Instead of the exception types, there could be a noexcept
2195  // expression.
2196  size_t Size = sizeof(FunctionProtoType) +
2197                NumArgs * sizeof(QualType);
2198  if (EPI.ExceptionSpecType == EST_Dynamic)
2199    Size += EPI.NumExceptions * sizeof(QualType);
2200  else if (EPI.ExceptionSpecType == EST_ComputedNoexcept) {
2201    Size += sizeof(Expr*);
2202  } else if (EPI.ExceptionSpecType == EST_Uninstantiated) {
2203    Size += 2 * sizeof(FunctionDecl*);
2204  }
2205  if (EPI.ConsumedArguments)
2206    Size += NumArgs * sizeof(bool);
2207
2208  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
2209  FunctionProtoType::ExtProtoInfo newEPI = EPI;
2210  newEPI.ExtInfo = EPI.ExtInfo.withCallingConv(CallConv);
2211  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, Canonical, newEPI);
2212  Types.push_back(FTP);
2213  FunctionProtoTypes.InsertNode(FTP, InsertPos);
2214  return QualType(FTP, 0);
2215}
2216
2217#ifndef NDEBUG
2218static bool NeedsInjectedClassNameType(const RecordDecl *D) {
2219  if (!isa<CXXRecordDecl>(D)) return false;
2220  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
2221  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
2222    return true;
2223  if (RD->getDescribedClassTemplate() &&
2224      !isa<ClassTemplateSpecializationDecl>(RD))
2225    return true;
2226  return false;
2227}
2228#endif
2229
2230/// getInjectedClassNameType - Return the unique reference to the
2231/// injected class name type for the specified templated declaration.
2232QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
2233                                              QualType TST) const {
2234  assert(NeedsInjectedClassNameType(Decl));
2235  if (Decl->TypeForDecl) {
2236    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2237  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDecl()) {
2238    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
2239    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2240    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2241  } else {
2242    Type *newType =
2243      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
2244    Decl->TypeForDecl = newType;
2245    Types.push_back(newType);
2246  }
2247  return QualType(Decl->TypeForDecl, 0);
2248}
2249
2250/// getTypeDeclType - Return the unique reference to the type for the
2251/// specified type declaration.
2252QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) const {
2253  assert(Decl && "Passed null for Decl param");
2254  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
2255
2256  if (const TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Decl))
2257    return getTypedefType(Typedef);
2258
2259  assert(!isa<TemplateTypeParmDecl>(Decl) &&
2260         "Template type parameter types are always available.");
2261
2262  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
2263    assert(!Record->getPreviousDecl() &&
2264           "struct/union has previous declaration");
2265    assert(!NeedsInjectedClassNameType(Record));
2266    return getRecordType(Record);
2267  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
2268    assert(!Enum->getPreviousDecl() &&
2269           "enum has previous declaration");
2270    return getEnumType(Enum);
2271  } else if (const UnresolvedUsingTypenameDecl *Using =
2272               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
2273    Type *newType = new (*this, TypeAlignment) UnresolvedUsingType(Using);
2274    Decl->TypeForDecl = newType;
2275    Types.push_back(newType);
2276  } else
2277    llvm_unreachable("TypeDecl without a type?");
2278
2279  return QualType(Decl->TypeForDecl, 0);
2280}
2281
2282/// getTypedefType - Return the unique reference to the type for the
2283/// specified typedef name decl.
2284QualType
2285ASTContext::getTypedefType(const TypedefNameDecl *Decl,
2286                           QualType Canonical) const {
2287  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2288
2289  if (Canonical.isNull())
2290    Canonical = getCanonicalType(Decl->getUnderlyingType());
2291  TypedefType *newType = new(*this, TypeAlignment)
2292    TypedefType(Type::Typedef, Decl, Canonical);
2293  Decl->TypeForDecl = newType;
2294  Types.push_back(newType);
2295  return QualType(newType, 0);
2296}
2297
2298QualType ASTContext::getRecordType(const RecordDecl *Decl) const {
2299  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2300
2301  if (const RecordDecl *PrevDecl = Decl->getPreviousDecl())
2302    if (PrevDecl->TypeForDecl)
2303      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2304
2305  RecordType *newType = new (*this, TypeAlignment) RecordType(Decl);
2306  Decl->TypeForDecl = newType;
2307  Types.push_back(newType);
2308  return QualType(newType, 0);
2309}
2310
2311QualType ASTContext::getEnumType(const EnumDecl *Decl) const {
2312  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2313
2314  if (const EnumDecl *PrevDecl = Decl->getPreviousDecl())
2315    if (PrevDecl->TypeForDecl)
2316      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2317
2318  EnumType *newType = new (*this, TypeAlignment) EnumType(Decl);
2319  Decl->TypeForDecl = newType;
2320  Types.push_back(newType);
2321  return QualType(newType, 0);
2322}
2323
2324QualType ASTContext::getAttributedType(AttributedType::Kind attrKind,
2325                                       QualType modifiedType,
2326                                       QualType equivalentType) {
2327  llvm::FoldingSetNodeID id;
2328  AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
2329
2330  void *insertPos = 0;
2331  AttributedType *type = AttributedTypes.FindNodeOrInsertPos(id, insertPos);
2332  if (type) return QualType(type, 0);
2333
2334  QualType canon = getCanonicalType(equivalentType);
2335  type = new (*this, TypeAlignment)
2336           AttributedType(canon, attrKind, modifiedType, equivalentType);
2337
2338  Types.push_back(type);
2339  AttributedTypes.InsertNode(type, insertPos);
2340
2341  return QualType(type, 0);
2342}
2343
2344
2345/// \brief Retrieve a substitution-result type.
2346QualType
2347ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
2348                                         QualType Replacement) const {
2349  assert(Replacement.isCanonical()
2350         && "replacement types must always be canonical");
2351
2352  llvm::FoldingSetNodeID ID;
2353  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
2354  void *InsertPos = 0;
2355  SubstTemplateTypeParmType *SubstParm
2356    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2357
2358  if (!SubstParm) {
2359    SubstParm = new (*this, TypeAlignment)
2360      SubstTemplateTypeParmType(Parm, Replacement);
2361    Types.push_back(SubstParm);
2362    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2363  }
2364
2365  return QualType(SubstParm, 0);
2366}
2367
2368/// \brief Retrieve a
2369QualType ASTContext::getSubstTemplateTypeParmPackType(
2370                                          const TemplateTypeParmType *Parm,
2371                                              const TemplateArgument &ArgPack) {
2372#ifndef NDEBUG
2373  for (TemplateArgument::pack_iterator P = ArgPack.pack_begin(),
2374                                    PEnd = ArgPack.pack_end();
2375       P != PEnd; ++P) {
2376    assert(P->getKind() == TemplateArgument::Type &&"Pack contains a non-type");
2377    assert(P->getAsType().isCanonical() && "Pack contains non-canonical type");
2378  }
2379#endif
2380
2381  llvm::FoldingSetNodeID ID;
2382  SubstTemplateTypeParmPackType::Profile(ID, Parm, ArgPack);
2383  void *InsertPos = 0;
2384  if (SubstTemplateTypeParmPackType *SubstParm
2385        = SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos))
2386    return QualType(SubstParm, 0);
2387
2388  QualType Canon;
2389  if (!Parm->isCanonicalUnqualified()) {
2390    Canon = getCanonicalType(QualType(Parm, 0));
2391    Canon = getSubstTemplateTypeParmPackType(cast<TemplateTypeParmType>(Canon),
2392                                             ArgPack);
2393    SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos);
2394  }
2395
2396  SubstTemplateTypeParmPackType *SubstParm
2397    = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
2398                                                               ArgPack);
2399  Types.push_back(SubstParm);
2400  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2401  return QualType(SubstParm, 0);
2402}
2403
2404/// \brief Retrieve the template type parameter type for a template
2405/// parameter or parameter pack with the given depth, index, and (optionally)
2406/// name.
2407QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
2408                                             bool ParameterPack,
2409                                             TemplateTypeParmDecl *TTPDecl) const {
2410  llvm::FoldingSetNodeID ID;
2411  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, TTPDecl);
2412  void *InsertPos = 0;
2413  TemplateTypeParmType *TypeParm
2414    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2415
2416  if (TypeParm)
2417    return QualType(TypeParm, 0);
2418
2419  if (TTPDecl) {
2420    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
2421    TypeParm = new (*this, TypeAlignment) TemplateTypeParmType(TTPDecl, Canon);
2422
2423    TemplateTypeParmType *TypeCheck
2424      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2425    assert(!TypeCheck && "Template type parameter canonical type broken");
2426    (void)TypeCheck;
2427  } else
2428    TypeParm = new (*this, TypeAlignment)
2429      TemplateTypeParmType(Depth, Index, ParameterPack);
2430
2431  Types.push_back(TypeParm);
2432  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
2433
2434  return QualType(TypeParm, 0);
2435}
2436
2437TypeSourceInfo *
2438ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
2439                                              SourceLocation NameLoc,
2440                                        const TemplateArgumentListInfo &Args,
2441                                              QualType Underlying) const {
2442  assert(!Name.getAsDependentTemplateName() &&
2443         "No dependent template names here!");
2444  QualType TST = getTemplateSpecializationType(Name, Args, Underlying);
2445
2446  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
2447  TemplateSpecializationTypeLoc TL
2448    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
2449  TL.setTemplateKeywordLoc(SourceLocation());
2450  TL.setTemplateNameLoc(NameLoc);
2451  TL.setLAngleLoc(Args.getLAngleLoc());
2452  TL.setRAngleLoc(Args.getRAngleLoc());
2453  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
2454    TL.setArgLocInfo(i, Args[i].getLocInfo());
2455  return DI;
2456}
2457
2458QualType
2459ASTContext::getTemplateSpecializationType(TemplateName Template,
2460                                          const TemplateArgumentListInfo &Args,
2461                                          QualType Underlying) const {
2462  assert(!Template.getAsDependentTemplateName() &&
2463         "No dependent template names here!");
2464
2465  unsigned NumArgs = Args.size();
2466
2467  SmallVector<TemplateArgument, 4> ArgVec;
2468  ArgVec.reserve(NumArgs);
2469  for (unsigned i = 0; i != NumArgs; ++i)
2470    ArgVec.push_back(Args[i].getArgument());
2471
2472  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
2473                                       Underlying);
2474}
2475
2476#ifndef NDEBUG
2477static bool hasAnyPackExpansions(const TemplateArgument *Args,
2478                                 unsigned NumArgs) {
2479  for (unsigned I = 0; I != NumArgs; ++I)
2480    if (Args[I].isPackExpansion())
2481      return true;
2482
2483  return true;
2484}
2485#endif
2486
2487QualType
2488ASTContext::getTemplateSpecializationType(TemplateName Template,
2489                                          const TemplateArgument *Args,
2490                                          unsigned NumArgs,
2491                                          QualType Underlying) const {
2492  assert(!Template.getAsDependentTemplateName() &&
2493         "No dependent template names here!");
2494  // Look through qualified template names.
2495  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2496    Template = TemplateName(QTN->getTemplateDecl());
2497
2498  bool IsTypeAlias =
2499    Template.getAsTemplateDecl() &&
2500    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
2501  QualType CanonType;
2502  if (!Underlying.isNull())
2503    CanonType = getCanonicalType(Underlying);
2504  else {
2505    // We can get here with an alias template when the specialization contains
2506    // a pack expansion that does not match up with a parameter pack.
2507    assert((!IsTypeAlias || hasAnyPackExpansions(Args, NumArgs)) &&
2508           "Caller must compute aliased type");
2509    IsTypeAlias = false;
2510    CanonType = getCanonicalTemplateSpecializationType(Template, Args,
2511                                                       NumArgs);
2512  }
2513
2514  // Allocate the (non-canonical) template specialization type, but don't
2515  // try to unique it: these types typically have location information that
2516  // we don't unique and don't want to lose.
2517  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
2518                       sizeof(TemplateArgument) * NumArgs +
2519                       (IsTypeAlias? sizeof(QualType) : 0),
2520                       TypeAlignment);
2521  TemplateSpecializationType *Spec
2522    = new (Mem) TemplateSpecializationType(Template, Args, NumArgs, CanonType,
2523                                         IsTypeAlias ? Underlying : QualType());
2524
2525  Types.push_back(Spec);
2526  return QualType(Spec, 0);
2527}
2528
2529QualType
2530ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
2531                                                   const TemplateArgument *Args,
2532                                                   unsigned NumArgs) const {
2533  assert(!Template.getAsDependentTemplateName() &&
2534         "No dependent template names here!");
2535
2536  // Look through qualified template names.
2537  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2538    Template = TemplateName(QTN->getTemplateDecl());
2539
2540  // Build the canonical template specialization type.
2541  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
2542  SmallVector<TemplateArgument, 4> CanonArgs;
2543  CanonArgs.reserve(NumArgs);
2544  for (unsigned I = 0; I != NumArgs; ++I)
2545    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
2546
2547  // Determine whether this canonical template specialization type already
2548  // exists.
2549  llvm::FoldingSetNodeID ID;
2550  TemplateSpecializationType::Profile(ID, CanonTemplate,
2551                                      CanonArgs.data(), NumArgs, *this);
2552
2553  void *InsertPos = 0;
2554  TemplateSpecializationType *Spec
2555    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2556
2557  if (!Spec) {
2558    // Allocate a new canonical template specialization type.
2559    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2560                          sizeof(TemplateArgument) * NumArgs),
2561                         TypeAlignment);
2562    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
2563                                                CanonArgs.data(), NumArgs,
2564                                                QualType(), QualType());
2565    Types.push_back(Spec);
2566    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
2567  }
2568
2569  assert(Spec->isDependentType() &&
2570         "Non-dependent template-id type must have a canonical type");
2571  return QualType(Spec, 0);
2572}
2573
2574QualType
2575ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
2576                              NestedNameSpecifier *NNS,
2577                              QualType NamedType) const {
2578  llvm::FoldingSetNodeID ID;
2579  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2580
2581  void *InsertPos = 0;
2582  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2583  if (T)
2584    return QualType(T, 0);
2585
2586  QualType Canon = NamedType;
2587  if (!Canon.isCanonical()) {
2588    Canon = getCanonicalType(NamedType);
2589    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2590    assert(!CheckT && "Elaborated canonical type broken");
2591    (void)CheckT;
2592  }
2593
2594  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2595  Types.push_back(T);
2596  ElaboratedTypes.InsertNode(T, InsertPos);
2597  return QualType(T, 0);
2598}
2599
2600QualType
2601ASTContext::getParenType(QualType InnerType) const {
2602  llvm::FoldingSetNodeID ID;
2603  ParenType::Profile(ID, InnerType);
2604
2605  void *InsertPos = 0;
2606  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2607  if (T)
2608    return QualType(T, 0);
2609
2610  QualType Canon = InnerType;
2611  if (!Canon.isCanonical()) {
2612    Canon = getCanonicalType(InnerType);
2613    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2614    assert(!CheckT && "Paren canonical type broken");
2615    (void)CheckT;
2616  }
2617
2618  T = new (*this) ParenType(InnerType, Canon);
2619  Types.push_back(T);
2620  ParenTypes.InsertNode(T, InsertPos);
2621  return QualType(T, 0);
2622}
2623
2624QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2625                                          NestedNameSpecifier *NNS,
2626                                          const IdentifierInfo *Name,
2627                                          QualType Canon) const {
2628  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2629
2630  if (Canon.isNull()) {
2631    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2632    ElaboratedTypeKeyword CanonKeyword = Keyword;
2633    if (Keyword == ETK_None)
2634      CanonKeyword = ETK_Typename;
2635
2636    if (CanonNNS != NNS || CanonKeyword != Keyword)
2637      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2638  }
2639
2640  llvm::FoldingSetNodeID ID;
2641  DependentNameType::Profile(ID, Keyword, NNS, Name);
2642
2643  void *InsertPos = 0;
2644  DependentNameType *T
2645    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2646  if (T)
2647    return QualType(T, 0);
2648
2649  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2650  Types.push_back(T);
2651  DependentNameTypes.InsertNode(T, InsertPos);
2652  return QualType(T, 0);
2653}
2654
2655QualType
2656ASTContext::getDependentTemplateSpecializationType(
2657                                 ElaboratedTypeKeyword Keyword,
2658                                 NestedNameSpecifier *NNS,
2659                                 const IdentifierInfo *Name,
2660                                 const TemplateArgumentListInfo &Args) const {
2661  // TODO: avoid this copy
2662  SmallVector<TemplateArgument, 16> ArgCopy;
2663  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2664    ArgCopy.push_back(Args[I].getArgument());
2665  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2666                                                ArgCopy.size(),
2667                                                ArgCopy.data());
2668}
2669
2670QualType
2671ASTContext::getDependentTemplateSpecializationType(
2672                                 ElaboratedTypeKeyword Keyword,
2673                                 NestedNameSpecifier *NNS,
2674                                 const IdentifierInfo *Name,
2675                                 unsigned NumArgs,
2676                                 const TemplateArgument *Args) const {
2677  assert((!NNS || NNS->isDependent()) &&
2678         "nested-name-specifier must be dependent");
2679
2680  llvm::FoldingSetNodeID ID;
2681  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2682                                               Name, NumArgs, Args);
2683
2684  void *InsertPos = 0;
2685  DependentTemplateSpecializationType *T
2686    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2687  if (T)
2688    return QualType(T, 0);
2689
2690  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2691
2692  ElaboratedTypeKeyword CanonKeyword = Keyword;
2693  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2694
2695  bool AnyNonCanonArgs = false;
2696  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2697  for (unsigned I = 0; I != NumArgs; ++I) {
2698    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2699    if (!CanonArgs[I].structurallyEquals(Args[I]))
2700      AnyNonCanonArgs = true;
2701  }
2702
2703  QualType Canon;
2704  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2705    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2706                                                   Name, NumArgs,
2707                                                   CanonArgs.data());
2708
2709    // Find the insert position again.
2710    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2711  }
2712
2713  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2714                        sizeof(TemplateArgument) * NumArgs),
2715                       TypeAlignment);
2716  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2717                                                    Name, NumArgs, Args, Canon);
2718  Types.push_back(T);
2719  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2720  return QualType(T, 0);
2721}
2722
2723QualType ASTContext::getPackExpansionType(QualType Pattern,
2724                                      llvm::Optional<unsigned> NumExpansions) {
2725  llvm::FoldingSetNodeID ID;
2726  PackExpansionType::Profile(ID, Pattern, NumExpansions);
2727
2728  assert(Pattern->containsUnexpandedParameterPack() &&
2729         "Pack expansions must expand one or more parameter packs");
2730  void *InsertPos = 0;
2731  PackExpansionType *T
2732    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2733  if (T)
2734    return QualType(T, 0);
2735
2736  QualType Canon;
2737  if (!Pattern.isCanonical()) {
2738    Canon = getPackExpansionType(getCanonicalType(Pattern), NumExpansions);
2739
2740    // Find the insert position again.
2741    PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2742  }
2743
2744  T = new (*this) PackExpansionType(Pattern, Canon, NumExpansions);
2745  Types.push_back(T);
2746  PackExpansionTypes.InsertNode(T, InsertPos);
2747  return QualType(T, 0);
2748}
2749
2750/// CmpProtocolNames - Comparison predicate for sorting protocols
2751/// alphabetically.
2752static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2753                            const ObjCProtocolDecl *RHS) {
2754  return LHS->getDeclName() < RHS->getDeclName();
2755}
2756
2757static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2758                                unsigned NumProtocols) {
2759  if (NumProtocols == 0) return true;
2760
2761  if (Protocols[0]->getCanonicalDecl() != Protocols[0])
2762    return false;
2763
2764  for (unsigned i = 1; i != NumProtocols; ++i)
2765    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]) ||
2766        Protocols[i]->getCanonicalDecl() != Protocols[i])
2767      return false;
2768  return true;
2769}
2770
2771static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2772                                   unsigned &NumProtocols) {
2773  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2774
2775  // Sort protocols, keyed by name.
2776  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2777
2778  // Canonicalize.
2779  for (unsigned I = 0, N = NumProtocols; I != N; ++I)
2780    Protocols[I] = Protocols[I]->getCanonicalDecl();
2781
2782  // Remove duplicates.
2783  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2784  NumProtocols = ProtocolsEnd-Protocols;
2785}
2786
2787QualType ASTContext::getObjCObjectType(QualType BaseType,
2788                                       ObjCProtocolDecl * const *Protocols,
2789                                       unsigned NumProtocols) const {
2790  // If the base type is an interface and there aren't any protocols
2791  // to add, then the interface type will do just fine.
2792  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2793    return BaseType;
2794
2795  // Look in the folding set for an existing type.
2796  llvm::FoldingSetNodeID ID;
2797  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2798  void *InsertPos = 0;
2799  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2800    return QualType(QT, 0);
2801
2802  // Build the canonical type, which has the canonical base type and
2803  // a sorted-and-uniqued list of protocols.
2804  QualType Canonical;
2805  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2806  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2807    if (!ProtocolsSorted) {
2808      SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2809                                                     Protocols + NumProtocols);
2810      unsigned UniqueCount = NumProtocols;
2811
2812      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2813      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2814                                    &Sorted[0], UniqueCount);
2815    } else {
2816      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2817                                    Protocols, NumProtocols);
2818    }
2819
2820    // Regenerate InsertPos.
2821    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2822  }
2823
2824  unsigned Size = sizeof(ObjCObjectTypeImpl);
2825  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2826  void *Mem = Allocate(Size, TypeAlignment);
2827  ObjCObjectTypeImpl *T =
2828    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2829
2830  Types.push_back(T);
2831  ObjCObjectTypes.InsertNode(T, InsertPos);
2832  return QualType(T, 0);
2833}
2834
2835/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2836/// the given object type.
2837QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
2838  llvm::FoldingSetNodeID ID;
2839  ObjCObjectPointerType::Profile(ID, ObjectT);
2840
2841  void *InsertPos = 0;
2842  if (ObjCObjectPointerType *QT =
2843              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2844    return QualType(QT, 0);
2845
2846  // Find the canonical object type.
2847  QualType Canonical;
2848  if (!ObjectT.isCanonical()) {
2849    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2850
2851    // Regenerate InsertPos.
2852    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2853  }
2854
2855  // No match.
2856  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2857  ObjCObjectPointerType *QType =
2858    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2859
2860  Types.push_back(QType);
2861  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2862  return QualType(QType, 0);
2863}
2864
2865/// getObjCInterfaceType - Return the unique reference to the type for the
2866/// specified ObjC interface decl. The list of protocols is optional.
2867QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
2868                                          ObjCInterfaceDecl *PrevDecl) const {
2869  if (Decl->TypeForDecl)
2870    return QualType(Decl->TypeForDecl, 0);
2871
2872  if (PrevDecl) {
2873    assert(PrevDecl->TypeForDecl && "previous decl has no TypeForDecl");
2874    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2875    return QualType(PrevDecl->TypeForDecl, 0);
2876  }
2877
2878  // Prefer the definition, if there is one.
2879  if (const ObjCInterfaceDecl *Def = Decl->getDefinition())
2880    Decl = Def;
2881
2882  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2883  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2884  Decl->TypeForDecl = T;
2885  Types.push_back(T);
2886  return QualType(T, 0);
2887}
2888
2889/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2890/// TypeOfExprType AST's (since expression's are never shared). For example,
2891/// multiple declarations that refer to "typeof(x)" all contain different
2892/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2893/// on canonical type's (which are always unique).
2894QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
2895  TypeOfExprType *toe;
2896  if (tofExpr->isTypeDependent()) {
2897    llvm::FoldingSetNodeID ID;
2898    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2899
2900    void *InsertPos = 0;
2901    DependentTypeOfExprType *Canon
2902      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2903    if (Canon) {
2904      // We already have a "canonical" version of an identical, dependent
2905      // typeof(expr) type. Use that as our canonical type.
2906      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2907                                          QualType((TypeOfExprType*)Canon, 0));
2908    } else {
2909      // Build a new, canonical typeof(expr) type.
2910      Canon
2911        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2912      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2913      toe = Canon;
2914    }
2915  } else {
2916    QualType Canonical = getCanonicalType(tofExpr->getType());
2917    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2918  }
2919  Types.push_back(toe);
2920  return QualType(toe, 0);
2921}
2922
2923/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2924/// TypeOfType AST's. The only motivation to unique these nodes would be
2925/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2926/// an issue. This doesn't effect the type checker, since it operates
2927/// on canonical type's (which are always unique).
2928QualType ASTContext::getTypeOfType(QualType tofType) const {
2929  QualType Canonical = getCanonicalType(tofType);
2930  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2931  Types.push_back(tot);
2932  return QualType(tot, 0);
2933}
2934
2935
2936/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2937/// DecltypeType AST's. The only motivation to unique these nodes would be
2938/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2939/// an issue. This doesn't effect the type checker, since it operates
2940/// on canonical types (which are always unique).
2941QualType ASTContext::getDecltypeType(Expr *e, QualType UnderlyingType) const {
2942  DecltypeType *dt;
2943
2944  // C++0x [temp.type]p2:
2945  //   If an expression e involves a template parameter, decltype(e) denotes a
2946  //   unique dependent type. Two such decltype-specifiers refer to the same
2947  //   type only if their expressions are equivalent (14.5.6.1).
2948  if (e->isInstantiationDependent()) {
2949    llvm::FoldingSetNodeID ID;
2950    DependentDecltypeType::Profile(ID, *this, e);
2951
2952    void *InsertPos = 0;
2953    DependentDecltypeType *Canon
2954      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2955    if (Canon) {
2956      // We already have a "canonical" version of an equivalent, dependent
2957      // decltype type. Use that as our canonical type.
2958      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2959                                       QualType((DecltypeType*)Canon, 0));
2960    } else {
2961      // Build a new, canonical typeof(expr) type.
2962      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2963      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2964      dt = Canon;
2965    }
2966  } else {
2967    dt = new (*this, TypeAlignment) DecltypeType(e, UnderlyingType,
2968                                      getCanonicalType(UnderlyingType));
2969  }
2970  Types.push_back(dt);
2971  return QualType(dt, 0);
2972}
2973
2974/// getUnaryTransformationType - We don't unique these, since the memory
2975/// savings are minimal and these are rare.
2976QualType ASTContext::getUnaryTransformType(QualType BaseType,
2977                                           QualType UnderlyingType,
2978                                           UnaryTransformType::UTTKind Kind)
2979    const {
2980  UnaryTransformType *Ty =
2981    new (*this, TypeAlignment) UnaryTransformType (BaseType, UnderlyingType,
2982                                                   Kind,
2983                                 UnderlyingType->isDependentType() ?
2984                                 QualType() : getCanonicalType(UnderlyingType));
2985  Types.push_back(Ty);
2986  return QualType(Ty, 0);
2987}
2988
2989/// getAutoType - We only unique auto types after they've been deduced.
2990QualType ASTContext::getAutoType(QualType DeducedType) const {
2991  void *InsertPos = 0;
2992  if (!DeducedType.isNull()) {
2993    // Look in the folding set for an existing type.
2994    llvm::FoldingSetNodeID ID;
2995    AutoType::Profile(ID, DeducedType);
2996    if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
2997      return QualType(AT, 0);
2998  }
2999
3000  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType);
3001  Types.push_back(AT);
3002  if (InsertPos)
3003    AutoTypes.InsertNode(AT, InsertPos);
3004  return QualType(AT, 0);
3005}
3006
3007/// getAtomicType - Return the uniqued reference to the atomic type for
3008/// the given value type.
3009QualType ASTContext::getAtomicType(QualType T) const {
3010  // Unique pointers, to guarantee there is only one pointer of a particular
3011  // structure.
3012  llvm::FoldingSetNodeID ID;
3013  AtomicType::Profile(ID, T);
3014
3015  void *InsertPos = 0;
3016  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
3017    return QualType(AT, 0);
3018
3019  // If the atomic value type isn't canonical, this won't be a canonical type
3020  // either, so fill in the canonical type field.
3021  QualType Canonical;
3022  if (!T.isCanonical()) {
3023    Canonical = getAtomicType(getCanonicalType(T));
3024
3025    // Get the new insert position for the node we care about.
3026    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
3027    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
3028  }
3029  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
3030  Types.push_back(New);
3031  AtomicTypes.InsertNode(New, InsertPos);
3032  return QualType(New, 0);
3033}
3034
3035/// getAutoDeductType - Get type pattern for deducing against 'auto'.
3036QualType ASTContext::getAutoDeductType() const {
3037  if (AutoDeductTy.isNull())
3038    AutoDeductTy = getAutoType(QualType());
3039  assert(!AutoDeductTy.isNull() && "can't build 'auto' pattern");
3040  return AutoDeductTy;
3041}
3042
3043/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
3044QualType ASTContext::getAutoRRefDeductType() const {
3045  if (AutoRRefDeductTy.isNull())
3046    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
3047  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
3048  return AutoRRefDeductTy;
3049}
3050
3051/// getTagDeclType - Return the unique reference to the type for the
3052/// specified TagDecl (struct/union/class/enum) decl.
3053QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
3054  assert (Decl);
3055  // FIXME: What is the design on getTagDeclType when it requires casting
3056  // away const?  mutable?
3057  return getTypeDeclType(const_cast<TagDecl*>(Decl));
3058}
3059
3060/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
3061/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
3062/// needs to agree with the definition in <stddef.h>.
3063CanQualType ASTContext::getSizeType() const {
3064  return getFromTargetType(Target->getSizeType());
3065}
3066
3067/// getIntMaxType - Return the unique type for "intmax_t" (C99 7.18.1.5).
3068CanQualType ASTContext::getIntMaxType() const {
3069  return getFromTargetType(Target->getIntMaxType());
3070}
3071
3072/// getUIntMaxType - Return the unique type for "uintmax_t" (C99 7.18.1.5).
3073CanQualType ASTContext::getUIntMaxType() const {
3074  return getFromTargetType(Target->getUIntMaxType());
3075}
3076
3077/// getSignedWCharType - Return the type of "signed wchar_t".
3078/// Used when in C++, as a GCC extension.
3079QualType ASTContext::getSignedWCharType() const {
3080  // FIXME: derive from "Target" ?
3081  return WCharTy;
3082}
3083
3084/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
3085/// Used when in C++, as a GCC extension.
3086QualType ASTContext::getUnsignedWCharType() const {
3087  // FIXME: derive from "Target" ?
3088  return UnsignedIntTy;
3089}
3090
3091/// getPointerDiffType - Return the unique type for "ptrdiff_t" (C99 7.17)
3092/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
3093QualType ASTContext::getPointerDiffType() const {
3094  return getFromTargetType(Target->getPtrDiffType(0));
3095}
3096
3097//===----------------------------------------------------------------------===//
3098//                              Type Operators
3099//===----------------------------------------------------------------------===//
3100
3101CanQualType ASTContext::getCanonicalParamType(QualType T) const {
3102  // Push qualifiers into arrays, and then discard any remaining
3103  // qualifiers.
3104  T = getCanonicalType(T);
3105  T = getVariableArrayDecayedType(T);
3106  const Type *Ty = T.getTypePtr();
3107  QualType Result;
3108  if (isa<ArrayType>(Ty)) {
3109    Result = getArrayDecayedType(QualType(Ty,0));
3110  } else if (isa<FunctionType>(Ty)) {
3111    Result = getPointerType(QualType(Ty, 0));
3112  } else {
3113    Result = QualType(Ty, 0);
3114  }
3115
3116  return CanQualType::CreateUnsafe(Result);
3117}
3118
3119QualType ASTContext::getUnqualifiedArrayType(QualType type,
3120                                             Qualifiers &quals) {
3121  SplitQualType splitType = type.getSplitUnqualifiedType();
3122
3123  // FIXME: getSplitUnqualifiedType() actually walks all the way to
3124  // the unqualified desugared type and then drops it on the floor.
3125  // We then have to strip that sugar back off with
3126  // getUnqualifiedDesugaredType(), which is silly.
3127  const ArrayType *AT =
3128    dyn_cast<ArrayType>(splitType.Ty->getUnqualifiedDesugaredType());
3129
3130  // If we don't have an array, just use the results in splitType.
3131  if (!AT) {
3132    quals = splitType.Quals;
3133    return QualType(splitType.Ty, 0);
3134  }
3135
3136  // Otherwise, recurse on the array's element type.
3137  QualType elementType = AT->getElementType();
3138  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
3139
3140  // If that didn't change the element type, AT has no qualifiers, so we
3141  // can just use the results in splitType.
3142  if (elementType == unqualElementType) {
3143    assert(quals.empty()); // from the recursive call
3144    quals = splitType.Quals;
3145    return QualType(splitType.Ty, 0);
3146  }
3147
3148  // Otherwise, add in the qualifiers from the outermost type, then
3149  // build the type back up.
3150  quals.addConsistentQualifiers(splitType.Quals);
3151
3152  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
3153    return getConstantArrayType(unqualElementType, CAT->getSize(),
3154                                CAT->getSizeModifier(), 0);
3155  }
3156
3157  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
3158    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
3159  }
3160
3161  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
3162    return getVariableArrayType(unqualElementType,
3163                                VAT->getSizeExpr(),
3164                                VAT->getSizeModifier(),
3165                                VAT->getIndexTypeCVRQualifiers(),
3166                                VAT->getBracketsRange());
3167  }
3168
3169  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
3170  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
3171                                    DSAT->getSizeModifier(), 0,
3172                                    SourceRange());
3173}
3174
3175/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
3176/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
3177/// they point to and return true. If T1 and T2 aren't pointer types
3178/// or pointer-to-member types, or if they are not similar at this
3179/// level, returns false and leaves T1 and T2 unchanged. Top-level
3180/// qualifiers on T1 and T2 are ignored. This function will typically
3181/// be called in a loop that successively "unwraps" pointer and
3182/// pointer-to-member types to compare them at each level.
3183bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
3184  const PointerType *T1PtrType = T1->getAs<PointerType>(),
3185                    *T2PtrType = T2->getAs<PointerType>();
3186  if (T1PtrType && T2PtrType) {
3187    T1 = T1PtrType->getPointeeType();
3188    T2 = T2PtrType->getPointeeType();
3189    return true;
3190  }
3191
3192  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
3193                          *T2MPType = T2->getAs<MemberPointerType>();
3194  if (T1MPType && T2MPType &&
3195      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
3196                             QualType(T2MPType->getClass(), 0))) {
3197    T1 = T1MPType->getPointeeType();
3198    T2 = T2MPType->getPointeeType();
3199    return true;
3200  }
3201
3202  if (getLangOpts().ObjC1) {
3203    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
3204                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
3205    if (T1OPType && T2OPType) {
3206      T1 = T1OPType->getPointeeType();
3207      T2 = T2OPType->getPointeeType();
3208      return true;
3209    }
3210  }
3211
3212  // FIXME: Block pointers, too?
3213
3214  return false;
3215}
3216
3217DeclarationNameInfo
3218ASTContext::getNameForTemplate(TemplateName Name,
3219                               SourceLocation NameLoc) const {
3220  switch (Name.getKind()) {
3221  case TemplateName::QualifiedTemplate:
3222  case TemplateName::Template:
3223    // DNInfo work in progress: CHECKME: what about DNLoc?
3224    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
3225                               NameLoc);
3226
3227  case TemplateName::OverloadedTemplate: {
3228    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
3229    // DNInfo work in progress: CHECKME: what about DNLoc?
3230    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
3231  }
3232
3233  case TemplateName::DependentTemplate: {
3234    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3235    DeclarationName DName;
3236    if (DTN->isIdentifier()) {
3237      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
3238      return DeclarationNameInfo(DName, NameLoc);
3239    } else {
3240      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
3241      // DNInfo work in progress: FIXME: source locations?
3242      DeclarationNameLoc DNLoc;
3243      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
3244      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
3245      return DeclarationNameInfo(DName, NameLoc, DNLoc);
3246    }
3247  }
3248
3249  case TemplateName::SubstTemplateTemplateParm: {
3250    SubstTemplateTemplateParmStorage *subst
3251      = Name.getAsSubstTemplateTemplateParm();
3252    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
3253                               NameLoc);
3254  }
3255
3256  case TemplateName::SubstTemplateTemplateParmPack: {
3257    SubstTemplateTemplateParmPackStorage *subst
3258      = Name.getAsSubstTemplateTemplateParmPack();
3259    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
3260                               NameLoc);
3261  }
3262  }
3263
3264  llvm_unreachable("bad template name kind!");
3265}
3266
3267TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
3268  switch (Name.getKind()) {
3269  case TemplateName::QualifiedTemplate:
3270  case TemplateName::Template: {
3271    TemplateDecl *Template = Name.getAsTemplateDecl();
3272    if (TemplateTemplateParmDecl *TTP
3273          = dyn_cast<TemplateTemplateParmDecl>(Template))
3274      Template = getCanonicalTemplateTemplateParmDecl(TTP);
3275
3276    // The canonical template name is the canonical template declaration.
3277    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
3278  }
3279
3280  case TemplateName::OverloadedTemplate:
3281    llvm_unreachable("cannot canonicalize overloaded template");
3282
3283  case TemplateName::DependentTemplate: {
3284    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3285    assert(DTN && "Non-dependent template names must refer to template decls.");
3286    return DTN->CanonicalTemplateName;
3287  }
3288
3289  case TemplateName::SubstTemplateTemplateParm: {
3290    SubstTemplateTemplateParmStorage *subst
3291      = Name.getAsSubstTemplateTemplateParm();
3292    return getCanonicalTemplateName(subst->getReplacement());
3293  }
3294
3295  case TemplateName::SubstTemplateTemplateParmPack: {
3296    SubstTemplateTemplateParmPackStorage *subst
3297                                  = Name.getAsSubstTemplateTemplateParmPack();
3298    TemplateTemplateParmDecl *canonParameter
3299      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
3300    TemplateArgument canonArgPack
3301      = getCanonicalTemplateArgument(subst->getArgumentPack());
3302    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
3303  }
3304  }
3305
3306  llvm_unreachable("bad template name!");
3307}
3308
3309bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
3310  X = getCanonicalTemplateName(X);
3311  Y = getCanonicalTemplateName(Y);
3312  return X.getAsVoidPointer() == Y.getAsVoidPointer();
3313}
3314
3315TemplateArgument
3316ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
3317  switch (Arg.getKind()) {
3318    case TemplateArgument::Null:
3319      return Arg;
3320
3321    case TemplateArgument::Expression:
3322      return Arg;
3323
3324    case TemplateArgument::Declaration: {
3325      if (Decl *D = Arg.getAsDecl())
3326          return TemplateArgument(D->getCanonicalDecl());
3327      return TemplateArgument((Decl*)0);
3328    }
3329
3330    case TemplateArgument::Template:
3331      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
3332
3333    case TemplateArgument::TemplateExpansion:
3334      return TemplateArgument(getCanonicalTemplateName(
3335                                         Arg.getAsTemplateOrTemplatePattern()),
3336                              Arg.getNumTemplateExpansions());
3337
3338    case TemplateArgument::Integral:
3339      return TemplateArgument(*Arg.getAsIntegral(),
3340                              getCanonicalType(Arg.getIntegralType()));
3341
3342    case TemplateArgument::Type:
3343      return TemplateArgument(getCanonicalType(Arg.getAsType()));
3344
3345    case TemplateArgument::Pack: {
3346      if (Arg.pack_size() == 0)
3347        return Arg;
3348
3349      TemplateArgument *CanonArgs
3350        = new (*this) TemplateArgument[Arg.pack_size()];
3351      unsigned Idx = 0;
3352      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
3353                                        AEnd = Arg.pack_end();
3354           A != AEnd; (void)++A, ++Idx)
3355        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
3356
3357      return TemplateArgument(CanonArgs, Arg.pack_size());
3358    }
3359  }
3360
3361  // Silence GCC warning
3362  llvm_unreachable("Unhandled template argument kind");
3363}
3364
3365NestedNameSpecifier *
3366ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
3367  if (!NNS)
3368    return 0;
3369
3370  switch (NNS->getKind()) {
3371  case NestedNameSpecifier::Identifier:
3372    // Canonicalize the prefix but keep the identifier the same.
3373    return NestedNameSpecifier::Create(*this,
3374                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
3375                                       NNS->getAsIdentifier());
3376
3377  case NestedNameSpecifier::Namespace:
3378    // A namespace is canonical; build a nested-name-specifier with
3379    // this namespace and no prefix.
3380    return NestedNameSpecifier::Create(*this, 0,
3381                                 NNS->getAsNamespace()->getOriginalNamespace());
3382
3383  case NestedNameSpecifier::NamespaceAlias:
3384    // A namespace is canonical; build a nested-name-specifier with
3385    // this namespace and no prefix.
3386    return NestedNameSpecifier::Create(*this, 0,
3387                                    NNS->getAsNamespaceAlias()->getNamespace()
3388                                                      ->getOriginalNamespace());
3389
3390  case NestedNameSpecifier::TypeSpec:
3391  case NestedNameSpecifier::TypeSpecWithTemplate: {
3392    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
3393
3394    // If we have some kind of dependent-named type (e.g., "typename T::type"),
3395    // break it apart into its prefix and identifier, then reconsititute those
3396    // as the canonical nested-name-specifier. This is required to canonicalize
3397    // a dependent nested-name-specifier involving typedefs of dependent-name
3398    // types, e.g.,
3399    //   typedef typename T::type T1;
3400    //   typedef typename T1::type T2;
3401    if (const DependentNameType *DNT = T->getAs<DependentNameType>())
3402      return NestedNameSpecifier::Create(*this, DNT->getQualifier(),
3403                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
3404
3405    // Otherwise, just canonicalize the type, and force it to be a TypeSpec.
3406    // FIXME: Why are TypeSpec and TypeSpecWithTemplate distinct in the
3407    // first place?
3408    return NestedNameSpecifier::Create(*this, 0, false,
3409                                       const_cast<Type*>(T.getTypePtr()));
3410  }
3411
3412  case NestedNameSpecifier::Global:
3413    // The global specifier is canonical and unique.
3414    return NNS;
3415  }
3416
3417  llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
3418}
3419
3420
3421const ArrayType *ASTContext::getAsArrayType(QualType T) const {
3422  // Handle the non-qualified case efficiently.
3423  if (!T.hasLocalQualifiers()) {
3424    // Handle the common positive case fast.
3425    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
3426      return AT;
3427  }
3428
3429  // Handle the common negative case fast.
3430  if (!isa<ArrayType>(T.getCanonicalType()))
3431    return 0;
3432
3433  // Apply any qualifiers from the array type to the element type.  This
3434  // implements C99 6.7.3p8: "If the specification of an array type includes
3435  // any type qualifiers, the element type is so qualified, not the array type."
3436
3437  // If we get here, we either have type qualifiers on the type, or we have
3438  // sugar such as a typedef in the way.  If we have type qualifiers on the type
3439  // we must propagate them down into the element type.
3440
3441  SplitQualType split = T.getSplitDesugaredType();
3442  Qualifiers qs = split.Quals;
3443
3444  // If we have a simple case, just return now.
3445  const ArrayType *ATy = dyn_cast<ArrayType>(split.Ty);
3446  if (ATy == 0 || qs.empty())
3447    return ATy;
3448
3449  // Otherwise, we have an array and we have qualifiers on it.  Push the
3450  // qualifiers into the array element type and return a new array type.
3451  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
3452
3453  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
3454    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
3455                                                CAT->getSizeModifier(),
3456                                           CAT->getIndexTypeCVRQualifiers()));
3457  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
3458    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
3459                                                  IAT->getSizeModifier(),
3460                                           IAT->getIndexTypeCVRQualifiers()));
3461
3462  if (const DependentSizedArrayType *DSAT
3463        = dyn_cast<DependentSizedArrayType>(ATy))
3464    return cast<ArrayType>(
3465                     getDependentSizedArrayType(NewEltTy,
3466                                                DSAT->getSizeExpr(),
3467                                                DSAT->getSizeModifier(),
3468                                              DSAT->getIndexTypeCVRQualifiers(),
3469                                                DSAT->getBracketsRange()));
3470
3471  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
3472  return cast<ArrayType>(getVariableArrayType(NewEltTy,
3473                                              VAT->getSizeExpr(),
3474                                              VAT->getSizeModifier(),
3475                                              VAT->getIndexTypeCVRQualifiers(),
3476                                              VAT->getBracketsRange()));
3477}
3478
3479QualType ASTContext::getAdjustedParameterType(QualType T) const {
3480  // C99 6.7.5.3p7:
3481  //   A declaration of a parameter as "array of type" shall be
3482  //   adjusted to "qualified pointer to type", where the type
3483  //   qualifiers (if any) are those specified within the [ and ] of
3484  //   the array type derivation.
3485  if (T->isArrayType())
3486    return getArrayDecayedType(T);
3487
3488  // C99 6.7.5.3p8:
3489  //   A declaration of a parameter as "function returning type"
3490  //   shall be adjusted to "pointer to function returning type", as
3491  //   in 6.3.2.1.
3492  if (T->isFunctionType())
3493    return getPointerType(T);
3494
3495  return T;
3496}
3497
3498QualType ASTContext::getSignatureParameterType(QualType T) const {
3499  T = getVariableArrayDecayedType(T);
3500  T = getAdjustedParameterType(T);
3501  return T.getUnqualifiedType();
3502}
3503
3504/// getArrayDecayedType - Return the properly qualified result of decaying the
3505/// specified array type to a pointer.  This operation is non-trivial when
3506/// handling typedefs etc.  The canonical type of "T" must be an array type,
3507/// this returns a pointer to a properly qualified element of the array.
3508///
3509/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
3510QualType ASTContext::getArrayDecayedType(QualType Ty) const {
3511  // Get the element type with 'getAsArrayType' so that we don't lose any
3512  // typedefs in the element type of the array.  This also handles propagation
3513  // of type qualifiers from the array type into the element type if present
3514  // (C99 6.7.3p8).
3515  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
3516  assert(PrettyArrayType && "Not an array type!");
3517
3518  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
3519
3520  // int x[restrict 4] ->  int *restrict
3521  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
3522}
3523
3524QualType ASTContext::getBaseElementType(const ArrayType *array) const {
3525  return getBaseElementType(array->getElementType());
3526}
3527
3528QualType ASTContext::getBaseElementType(QualType type) const {
3529  Qualifiers qs;
3530  while (true) {
3531    SplitQualType split = type.getSplitDesugaredType();
3532    const ArrayType *array = split.Ty->getAsArrayTypeUnsafe();
3533    if (!array) break;
3534
3535    type = array->getElementType();
3536    qs.addConsistentQualifiers(split.Quals);
3537  }
3538
3539  return getQualifiedType(type, qs);
3540}
3541
3542/// getConstantArrayElementCount - Returns number of constant array elements.
3543uint64_t
3544ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
3545  uint64_t ElementCount = 1;
3546  do {
3547    ElementCount *= CA->getSize().getZExtValue();
3548    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
3549  } while (CA);
3550  return ElementCount;
3551}
3552
3553/// getFloatingRank - Return a relative rank for floating point types.
3554/// This routine will assert if passed a built-in type that isn't a float.
3555static FloatingRank getFloatingRank(QualType T) {
3556  if (const ComplexType *CT = T->getAs<ComplexType>())
3557    return getFloatingRank(CT->getElementType());
3558
3559  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
3560  switch (T->getAs<BuiltinType>()->getKind()) {
3561  default: llvm_unreachable("getFloatingRank(): not a floating type");
3562  case BuiltinType::Half:       return HalfRank;
3563  case BuiltinType::Float:      return FloatRank;
3564  case BuiltinType::Double:     return DoubleRank;
3565  case BuiltinType::LongDouble: return LongDoubleRank;
3566  }
3567}
3568
3569/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
3570/// point or a complex type (based on typeDomain/typeSize).
3571/// 'typeDomain' is a real floating point or complex type.
3572/// 'typeSize' is a real floating point or complex type.
3573QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
3574                                                       QualType Domain) const {
3575  FloatingRank EltRank = getFloatingRank(Size);
3576  if (Domain->isComplexType()) {
3577    switch (EltRank) {
3578    case HalfRank: llvm_unreachable("Complex half is not supported");
3579    case FloatRank:      return FloatComplexTy;
3580    case DoubleRank:     return DoubleComplexTy;
3581    case LongDoubleRank: return LongDoubleComplexTy;
3582    }
3583  }
3584
3585  assert(Domain->isRealFloatingType() && "Unknown domain!");
3586  switch (EltRank) {
3587  case HalfRank: llvm_unreachable("Half ranks are not valid here");
3588  case FloatRank:      return FloatTy;
3589  case DoubleRank:     return DoubleTy;
3590  case LongDoubleRank: return LongDoubleTy;
3591  }
3592  llvm_unreachable("getFloatingRank(): illegal value for rank");
3593}
3594
3595/// getFloatingTypeOrder - Compare the rank of the two specified floating
3596/// point types, ignoring the domain of the type (i.e. 'double' ==
3597/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3598/// LHS < RHS, return -1.
3599int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
3600  FloatingRank LHSR = getFloatingRank(LHS);
3601  FloatingRank RHSR = getFloatingRank(RHS);
3602
3603  if (LHSR == RHSR)
3604    return 0;
3605  if (LHSR > RHSR)
3606    return 1;
3607  return -1;
3608}
3609
3610/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
3611/// routine will assert if passed a built-in type that isn't an integer or enum,
3612/// or if it is not canonicalized.
3613unsigned ASTContext::getIntegerRank(const Type *T) const {
3614  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
3615
3616  switch (cast<BuiltinType>(T)->getKind()) {
3617  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
3618  case BuiltinType::Bool:
3619    return 1 + (getIntWidth(BoolTy) << 3);
3620  case BuiltinType::Char_S:
3621  case BuiltinType::Char_U:
3622  case BuiltinType::SChar:
3623  case BuiltinType::UChar:
3624    return 2 + (getIntWidth(CharTy) << 3);
3625  case BuiltinType::Short:
3626  case BuiltinType::UShort:
3627    return 3 + (getIntWidth(ShortTy) << 3);
3628  case BuiltinType::Int:
3629  case BuiltinType::UInt:
3630    return 4 + (getIntWidth(IntTy) << 3);
3631  case BuiltinType::Long:
3632  case BuiltinType::ULong:
3633    return 5 + (getIntWidth(LongTy) << 3);
3634  case BuiltinType::LongLong:
3635  case BuiltinType::ULongLong:
3636    return 6 + (getIntWidth(LongLongTy) << 3);
3637  case BuiltinType::Int128:
3638  case BuiltinType::UInt128:
3639    return 7 + (getIntWidth(Int128Ty) << 3);
3640  }
3641}
3642
3643/// \brief Whether this is a promotable bitfield reference according
3644/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
3645///
3646/// \returns the type this bit-field will promote to, or NULL if no
3647/// promotion occurs.
3648QualType ASTContext::isPromotableBitField(Expr *E) const {
3649  if (E->isTypeDependent() || E->isValueDependent())
3650    return QualType();
3651
3652  FieldDecl *Field = E->getBitField();
3653  if (!Field)
3654    return QualType();
3655
3656  QualType FT = Field->getType();
3657
3658  uint64_t BitWidth = Field->getBitWidthValue(*this);
3659  uint64_t IntSize = getTypeSize(IntTy);
3660  // GCC extension compatibility: if the bit-field size is less than or equal
3661  // to the size of int, it gets promoted no matter what its type is.
3662  // For instance, unsigned long bf : 4 gets promoted to signed int.
3663  if (BitWidth < IntSize)
3664    return IntTy;
3665
3666  if (BitWidth == IntSize)
3667    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
3668
3669  // Types bigger than int are not subject to promotions, and therefore act
3670  // like the base type.
3671  // FIXME: This doesn't quite match what gcc does, but what gcc does here
3672  // is ridiculous.
3673  return QualType();
3674}
3675
3676/// getPromotedIntegerType - Returns the type that Promotable will
3677/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
3678/// integer type.
3679QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
3680  assert(!Promotable.isNull());
3681  assert(Promotable->isPromotableIntegerType());
3682  if (const EnumType *ET = Promotable->getAs<EnumType>())
3683    return ET->getDecl()->getPromotionType();
3684
3685  if (const BuiltinType *BT = Promotable->getAs<BuiltinType>()) {
3686    // C++ [conv.prom]: A prvalue of type char16_t, char32_t, or wchar_t
3687    // (3.9.1) can be converted to a prvalue of the first of the following
3688    // types that can represent all the values of its underlying type:
3689    // int, unsigned int, long int, unsigned long int, long long int, or
3690    // unsigned long long int [...]
3691    // FIXME: Is there some better way to compute this?
3692    if (BT->getKind() == BuiltinType::WChar_S ||
3693        BT->getKind() == BuiltinType::WChar_U ||
3694        BT->getKind() == BuiltinType::Char16 ||
3695        BT->getKind() == BuiltinType::Char32) {
3696      bool FromIsSigned = BT->getKind() == BuiltinType::WChar_S;
3697      uint64_t FromSize = getTypeSize(BT);
3698      QualType PromoteTypes[] = { IntTy, UnsignedIntTy, LongTy, UnsignedLongTy,
3699                                  LongLongTy, UnsignedLongLongTy };
3700      for (size_t Idx = 0; Idx < llvm::array_lengthof(PromoteTypes); ++Idx) {
3701        uint64_t ToSize = getTypeSize(PromoteTypes[Idx]);
3702        if (FromSize < ToSize ||
3703            (FromSize == ToSize &&
3704             FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType()))
3705          return PromoteTypes[Idx];
3706      }
3707      llvm_unreachable("char type should fit into long long");
3708    }
3709  }
3710
3711  // At this point, we should have a signed or unsigned integer type.
3712  if (Promotable->isSignedIntegerType())
3713    return IntTy;
3714  uint64_t PromotableSize = getTypeSize(Promotable);
3715  uint64_t IntSize = getTypeSize(IntTy);
3716  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3717  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3718}
3719
3720/// \brief Recurses in pointer/array types until it finds an objc retainable
3721/// type and returns its ownership.
3722Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
3723  while (!T.isNull()) {
3724    if (T.getObjCLifetime() != Qualifiers::OCL_None)
3725      return T.getObjCLifetime();
3726    if (T->isArrayType())
3727      T = getBaseElementType(T);
3728    else if (const PointerType *PT = T->getAs<PointerType>())
3729      T = PT->getPointeeType();
3730    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3731      T = RT->getPointeeType();
3732    else
3733      break;
3734  }
3735
3736  return Qualifiers::OCL_None;
3737}
3738
3739/// getIntegerTypeOrder - Returns the highest ranked integer type:
3740/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3741/// LHS < RHS, return -1.
3742int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
3743  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
3744  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
3745  if (LHSC == RHSC) return 0;
3746
3747  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3748  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3749
3750  unsigned LHSRank = getIntegerRank(LHSC);
3751  unsigned RHSRank = getIntegerRank(RHSC);
3752
3753  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3754    if (LHSRank == RHSRank) return 0;
3755    return LHSRank > RHSRank ? 1 : -1;
3756  }
3757
3758  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3759  if (LHSUnsigned) {
3760    // If the unsigned [LHS] type is larger, return it.
3761    if (LHSRank >= RHSRank)
3762      return 1;
3763
3764    // If the signed type can represent all values of the unsigned type, it
3765    // wins.  Because we are dealing with 2's complement and types that are
3766    // powers of two larger than each other, this is always safe.
3767    return -1;
3768  }
3769
3770  // If the unsigned [RHS] type is larger, return it.
3771  if (RHSRank >= LHSRank)
3772    return -1;
3773
3774  // If the signed type can represent all values of the unsigned type, it
3775  // wins.  Because we are dealing with 2's complement and types that are
3776  // powers of two larger than each other, this is always safe.
3777  return 1;
3778}
3779
3780static RecordDecl *
3781CreateRecordDecl(const ASTContext &Ctx, RecordDecl::TagKind TK,
3782                 DeclContext *DC, IdentifierInfo *Id) {
3783  SourceLocation Loc;
3784  if (Ctx.getLangOpts().CPlusPlus)
3785    return CXXRecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3786  else
3787    return RecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3788}
3789
3790// getCFConstantStringType - Return the type used for constant CFStrings.
3791QualType ASTContext::getCFConstantStringType() const {
3792  if (!CFConstantStringTypeDecl) {
3793    CFConstantStringTypeDecl =
3794      CreateRecordDecl(*this, TTK_Struct, TUDecl,
3795                       &Idents.get("NSConstantString"));
3796    CFConstantStringTypeDecl->startDefinition();
3797
3798    QualType FieldTypes[4];
3799
3800    // const int *isa;
3801    FieldTypes[0] = getPointerType(IntTy.withConst());
3802    // int flags;
3803    FieldTypes[1] = IntTy;
3804    // const char *str;
3805    FieldTypes[2] = getPointerType(CharTy.withConst());
3806    // long length;
3807    FieldTypes[3] = LongTy;
3808
3809    // Create fields
3810    for (unsigned i = 0; i < 4; ++i) {
3811      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3812                                           SourceLocation(),
3813                                           SourceLocation(), 0,
3814                                           FieldTypes[i], /*TInfo=*/0,
3815                                           /*BitWidth=*/0,
3816                                           /*Mutable=*/false,
3817                                           /*HasInit=*/false);
3818      Field->setAccess(AS_public);
3819      CFConstantStringTypeDecl->addDecl(Field);
3820    }
3821
3822    CFConstantStringTypeDecl->completeDefinition();
3823  }
3824
3825  return getTagDeclType(CFConstantStringTypeDecl);
3826}
3827
3828void ASTContext::setCFConstantStringType(QualType T) {
3829  const RecordType *Rec = T->getAs<RecordType>();
3830  assert(Rec && "Invalid CFConstantStringType");
3831  CFConstantStringTypeDecl = Rec->getDecl();
3832}
3833
3834QualType ASTContext::getBlockDescriptorType() const {
3835  if (BlockDescriptorType)
3836    return getTagDeclType(BlockDescriptorType);
3837
3838  RecordDecl *T;
3839  // FIXME: Needs the FlagAppleBlock bit.
3840  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3841                       &Idents.get("__block_descriptor"));
3842  T->startDefinition();
3843
3844  QualType FieldTypes[] = {
3845    UnsignedLongTy,
3846    UnsignedLongTy,
3847  };
3848
3849  const char *FieldNames[] = {
3850    "reserved",
3851    "Size"
3852  };
3853
3854  for (size_t i = 0; i < 2; ++i) {
3855    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3856                                         SourceLocation(),
3857                                         &Idents.get(FieldNames[i]),
3858                                         FieldTypes[i], /*TInfo=*/0,
3859                                         /*BitWidth=*/0,
3860                                         /*Mutable=*/false,
3861                                         /*HasInit=*/false);
3862    Field->setAccess(AS_public);
3863    T->addDecl(Field);
3864  }
3865
3866  T->completeDefinition();
3867
3868  BlockDescriptorType = T;
3869
3870  return getTagDeclType(BlockDescriptorType);
3871}
3872
3873QualType ASTContext::getBlockDescriptorExtendedType() const {
3874  if (BlockDescriptorExtendedType)
3875    return getTagDeclType(BlockDescriptorExtendedType);
3876
3877  RecordDecl *T;
3878  // FIXME: Needs the FlagAppleBlock bit.
3879  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3880                       &Idents.get("__block_descriptor_withcopydispose"));
3881  T->startDefinition();
3882
3883  QualType FieldTypes[] = {
3884    UnsignedLongTy,
3885    UnsignedLongTy,
3886    getPointerType(VoidPtrTy),
3887    getPointerType(VoidPtrTy)
3888  };
3889
3890  const char *FieldNames[] = {
3891    "reserved",
3892    "Size",
3893    "CopyFuncPtr",
3894    "DestroyFuncPtr"
3895  };
3896
3897  for (size_t i = 0; i < 4; ++i) {
3898    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3899                                         SourceLocation(),
3900                                         &Idents.get(FieldNames[i]),
3901                                         FieldTypes[i], /*TInfo=*/0,
3902                                         /*BitWidth=*/0,
3903                                         /*Mutable=*/false,
3904                                         /*HasInit=*/false);
3905    Field->setAccess(AS_public);
3906    T->addDecl(Field);
3907  }
3908
3909  T->completeDefinition();
3910
3911  BlockDescriptorExtendedType = T;
3912
3913  return getTagDeclType(BlockDescriptorExtendedType);
3914}
3915
3916bool ASTContext::BlockRequiresCopying(QualType Ty) const {
3917  if (Ty->isObjCRetainableType())
3918    return true;
3919  if (getLangOpts().CPlusPlus) {
3920    if (const RecordType *RT = Ty->getAs<RecordType>()) {
3921      CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
3922      return RD->hasConstCopyConstructor();
3923
3924    }
3925  }
3926  return false;
3927}
3928
3929QualType
3930ASTContext::BuildByRefType(StringRef DeclName, QualType Ty) const {
3931  //  type = struct __Block_byref_1_X {
3932  //    void *__isa;
3933  //    struct __Block_byref_1_X *__forwarding;
3934  //    unsigned int __flags;
3935  //    unsigned int __size;
3936  //    void *__copy_helper;            // as needed
3937  //    void *__destroy_help            // as needed
3938  //    int X;
3939  //  } *
3940
3941  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3942
3943  // FIXME: Move up
3944  SmallString<36> Name;
3945  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3946                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3947  RecordDecl *T;
3948  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, &Idents.get(Name.str()));
3949  T->startDefinition();
3950  QualType Int32Ty = IntTy;
3951  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3952  QualType FieldTypes[] = {
3953    getPointerType(VoidPtrTy),
3954    getPointerType(getTagDeclType(T)),
3955    Int32Ty,
3956    Int32Ty,
3957    getPointerType(VoidPtrTy),
3958    getPointerType(VoidPtrTy),
3959    Ty
3960  };
3961
3962  StringRef FieldNames[] = {
3963    "__isa",
3964    "__forwarding",
3965    "__flags",
3966    "__size",
3967    "__copy_helper",
3968    "__destroy_helper",
3969    DeclName,
3970  };
3971
3972  for (size_t i = 0; i < 7; ++i) {
3973    if (!HasCopyAndDispose && i >=4 && i <= 5)
3974      continue;
3975    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3976                                         SourceLocation(),
3977                                         &Idents.get(FieldNames[i]),
3978                                         FieldTypes[i], /*TInfo=*/0,
3979                                         /*BitWidth=*/0, /*Mutable=*/false,
3980                                         /*HasInit=*/false);
3981    Field->setAccess(AS_public);
3982    T->addDecl(Field);
3983  }
3984
3985  T->completeDefinition();
3986
3987  return getPointerType(getTagDeclType(T));
3988}
3989
3990TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
3991  if (!ObjCInstanceTypeDecl)
3992    ObjCInstanceTypeDecl = TypedefDecl::Create(*this,
3993                                               getTranslationUnitDecl(),
3994                                               SourceLocation(),
3995                                               SourceLocation(),
3996                                               &Idents.get("instancetype"),
3997                                     getTrivialTypeSourceInfo(getObjCIdType()));
3998  return ObjCInstanceTypeDecl;
3999}
4000
4001// This returns true if a type has been typedefed to BOOL:
4002// typedef <type> BOOL;
4003static bool isTypeTypedefedAsBOOL(QualType T) {
4004  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
4005    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
4006      return II->isStr("BOOL");
4007
4008  return false;
4009}
4010
4011/// getObjCEncodingTypeSize returns size of type for objective-c encoding
4012/// purpose.
4013CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
4014  if (!type->isIncompleteArrayType() && type->isIncompleteType())
4015    return CharUnits::Zero();
4016
4017  CharUnits sz = getTypeSizeInChars(type);
4018
4019  // Make all integer and enum types at least as large as an int
4020  if (sz.isPositive() && type->isIntegralOrEnumerationType())
4021    sz = std::max(sz, getTypeSizeInChars(IntTy));
4022  // Treat arrays as pointers, since that's how they're passed in.
4023  else if (type->isArrayType())
4024    sz = getTypeSizeInChars(VoidPtrTy);
4025  return sz;
4026}
4027
4028static inline
4029std::string charUnitsToString(const CharUnits &CU) {
4030  return llvm::itostr(CU.getQuantity());
4031}
4032
4033/// getObjCEncodingForBlock - Return the encoded type for this block
4034/// declaration.
4035std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
4036  std::string S;
4037
4038  const BlockDecl *Decl = Expr->getBlockDecl();
4039  QualType BlockTy =
4040      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
4041  // Encode result type.
4042  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
4043  // Compute size of all parameters.
4044  // Start with computing size of a pointer in number of bytes.
4045  // FIXME: There might(should) be a better way of doing this computation!
4046  SourceLocation Loc;
4047  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4048  CharUnits ParmOffset = PtrSize;
4049  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
4050       E = Decl->param_end(); PI != E; ++PI) {
4051    QualType PType = (*PI)->getType();
4052    CharUnits sz = getObjCEncodingTypeSize(PType);
4053    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
4054    ParmOffset += sz;
4055  }
4056  // Size of the argument frame
4057  S += charUnitsToString(ParmOffset);
4058  // Block pointer and offset.
4059  S += "@?0";
4060
4061  // Argument types.
4062  ParmOffset = PtrSize;
4063  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
4064       Decl->param_end(); PI != E; ++PI) {
4065    ParmVarDecl *PVDecl = *PI;
4066    QualType PType = PVDecl->getOriginalType();
4067    if (const ArrayType *AT =
4068          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4069      // Use array's original type only if it has known number of
4070      // elements.
4071      if (!isa<ConstantArrayType>(AT))
4072        PType = PVDecl->getType();
4073    } else if (PType->isFunctionType())
4074      PType = PVDecl->getType();
4075    getObjCEncodingForType(PType, S);
4076    S += charUnitsToString(ParmOffset);
4077    ParmOffset += getObjCEncodingTypeSize(PType);
4078  }
4079
4080  return S;
4081}
4082
4083bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
4084                                                std::string& S) {
4085  // Encode result type.
4086  getObjCEncodingForType(Decl->getResultType(), S);
4087  CharUnits ParmOffset;
4088  // Compute size of all parameters.
4089  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4090       E = Decl->param_end(); PI != E; ++PI) {
4091    QualType PType = (*PI)->getType();
4092    CharUnits sz = getObjCEncodingTypeSize(PType);
4093    if (sz.isZero())
4094      return true;
4095
4096    assert (sz.isPositive() &&
4097        "getObjCEncodingForFunctionDecl - Incomplete param type");
4098    ParmOffset += sz;
4099  }
4100  S += charUnitsToString(ParmOffset);
4101  ParmOffset = CharUnits::Zero();
4102
4103  // Argument types.
4104  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4105       E = Decl->param_end(); PI != E; ++PI) {
4106    ParmVarDecl *PVDecl = *PI;
4107    QualType PType = PVDecl->getOriginalType();
4108    if (const ArrayType *AT =
4109          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4110      // Use array's original type only if it has known number of
4111      // elements.
4112      if (!isa<ConstantArrayType>(AT))
4113        PType = PVDecl->getType();
4114    } else if (PType->isFunctionType())
4115      PType = PVDecl->getType();
4116    getObjCEncodingForType(PType, S);
4117    S += charUnitsToString(ParmOffset);
4118    ParmOffset += getObjCEncodingTypeSize(PType);
4119  }
4120
4121  return false;
4122}
4123
4124/// getObjCEncodingForMethodParameter - Return the encoded type for a single
4125/// method parameter or return type. If Extended, include class names and
4126/// block object types.
4127void ASTContext::getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
4128                                                   QualType T, std::string& S,
4129                                                   bool Extended) const {
4130  // Encode type qualifer, 'in', 'inout', etc. for the parameter.
4131  getObjCEncodingForTypeQualifier(QT, S);
4132  // Encode parameter type.
4133  getObjCEncodingForTypeImpl(T, S, true, true, 0,
4134                             true     /*OutermostType*/,
4135                             false    /*EncodingProperty*/,
4136                             false    /*StructField*/,
4137                             Extended /*EncodeBlockParameters*/,
4138                             Extended /*EncodeClassNames*/);
4139}
4140
4141/// getObjCEncodingForMethodDecl - Return the encoded type for this method
4142/// declaration.
4143bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
4144                                              std::string& S,
4145                                              bool Extended) const {
4146  // FIXME: This is not very efficient.
4147  // Encode return type.
4148  getObjCEncodingForMethodParameter(Decl->getObjCDeclQualifier(),
4149                                    Decl->getResultType(), S, Extended);
4150  // Compute size of all parameters.
4151  // Start with computing size of a pointer in number of bytes.
4152  // FIXME: There might(should) be a better way of doing this computation!
4153  SourceLocation Loc;
4154  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4155  // The first two arguments (self and _cmd) are pointers; account for
4156  // their size.
4157  CharUnits ParmOffset = 2 * PtrSize;
4158  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4159       E = Decl->sel_param_end(); PI != E; ++PI) {
4160    QualType PType = (*PI)->getType();
4161    CharUnits sz = getObjCEncodingTypeSize(PType);
4162    if (sz.isZero())
4163      return true;
4164
4165    assert (sz.isPositive() &&
4166        "getObjCEncodingForMethodDecl - Incomplete param type");
4167    ParmOffset += sz;
4168  }
4169  S += charUnitsToString(ParmOffset);
4170  S += "@0:";
4171  S += charUnitsToString(PtrSize);
4172
4173  // Argument types.
4174  ParmOffset = 2 * PtrSize;
4175  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4176       E = Decl->sel_param_end(); PI != E; ++PI) {
4177    const ParmVarDecl *PVDecl = *PI;
4178    QualType PType = PVDecl->getOriginalType();
4179    if (const ArrayType *AT =
4180          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4181      // Use array's original type only if it has known number of
4182      // elements.
4183      if (!isa<ConstantArrayType>(AT))
4184        PType = PVDecl->getType();
4185    } else if (PType->isFunctionType())
4186      PType = PVDecl->getType();
4187    getObjCEncodingForMethodParameter(PVDecl->getObjCDeclQualifier(),
4188                                      PType, S, Extended);
4189    S += charUnitsToString(ParmOffset);
4190    ParmOffset += getObjCEncodingTypeSize(PType);
4191  }
4192
4193  return false;
4194}
4195
4196/// getObjCEncodingForPropertyDecl - Return the encoded type for this
4197/// property declaration. If non-NULL, Container must be either an
4198/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
4199/// NULL when getting encodings for protocol properties.
4200/// Property attributes are stored as a comma-delimited C string. The simple
4201/// attributes readonly and bycopy are encoded as single characters. The
4202/// parametrized attributes, getter=name, setter=name, and ivar=name, are
4203/// encoded as single characters, followed by an identifier. Property types
4204/// are also encoded as a parametrized attribute. The characters used to encode
4205/// these attributes are defined by the following enumeration:
4206/// @code
4207/// enum PropertyAttributes {
4208/// kPropertyReadOnly = 'R',   // property is read-only.
4209/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
4210/// kPropertyByref = '&',  // property is a reference to the value last assigned
4211/// kPropertyDynamic = 'D',    // property is dynamic
4212/// kPropertyGetter = 'G',     // followed by getter selector name
4213/// kPropertySetter = 'S',     // followed by setter selector name
4214/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
4215/// kPropertyType = 'T'              // followed by old-style type encoding.
4216/// kPropertyWeak = 'W'              // 'weak' property
4217/// kPropertyStrong = 'P'            // property GC'able
4218/// kPropertyNonAtomic = 'N'         // property non-atomic
4219/// };
4220/// @endcode
4221void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
4222                                                const Decl *Container,
4223                                                std::string& S) const {
4224  // Collect information from the property implementation decl(s).
4225  bool Dynamic = false;
4226  ObjCPropertyImplDecl *SynthesizePID = 0;
4227
4228  // FIXME: Duplicated code due to poor abstraction.
4229  if (Container) {
4230    if (const ObjCCategoryImplDecl *CID =
4231        dyn_cast<ObjCCategoryImplDecl>(Container)) {
4232      for (ObjCCategoryImplDecl::propimpl_iterator
4233             i = CID->propimpl_begin(), e = CID->propimpl_end();
4234           i != e; ++i) {
4235        ObjCPropertyImplDecl *PID = &*i;
4236        if (PID->getPropertyDecl() == PD) {
4237          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4238            Dynamic = true;
4239          } else {
4240            SynthesizePID = PID;
4241          }
4242        }
4243      }
4244    } else {
4245      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
4246      for (ObjCCategoryImplDecl::propimpl_iterator
4247             i = OID->propimpl_begin(), e = OID->propimpl_end();
4248           i != e; ++i) {
4249        ObjCPropertyImplDecl *PID = &*i;
4250        if (PID->getPropertyDecl() == PD) {
4251          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4252            Dynamic = true;
4253          } else {
4254            SynthesizePID = PID;
4255          }
4256        }
4257      }
4258    }
4259  }
4260
4261  // FIXME: This is not very efficient.
4262  S = "T";
4263
4264  // Encode result type.
4265  // GCC has some special rules regarding encoding of properties which
4266  // closely resembles encoding of ivars.
4267  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
4268                             true /* outermost type */,
4269                             true /* encoding for property */);
4270
4271  if (PD->isReadOnly()) {
4272    S += ",R";
4273  } else {
4274    switch (PD->getSetterKind()) {
4275    case ObjCPropertyDecl::Assign: break;
4276    case ObjCPropertyDecl::Copy:   S += ",C"; break;
4277    case ObjCPropertyDecl::Retain: S += ",&"; break;
4278    case ObjCPropertyDecl::Weak:   S += ",W"; break;
4279    }
4280  }
4281
4282  // It really isn't clear at all what this means, since properties
4283  // are "dynamic by default".
4284  if (Dynamic)
4285    S += ",D";
4286
4287  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
4288    S += ",N";
4289
4290  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
4291    S += ",G";
4292    S += PD->getGetterName().getAsString();
4293  }
4294
4295  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
4296    S += ",S";
4297    S += PD->getSetterName().getAsString();
4298  }
4299
4300  if (SynthesizePID) {
4301    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
4302    S += ",V";
4303    S += OID->getNameAsString();
4304  }
4305
4306  // FIXME: OBJCGC: weak & strong
4307}
4308
4309/// getLegacyIntegralTypeEncoding -
4310/// Another legacy compatibility encoding: 32-bit longs are encoded as
4311/// 'l' or 'L' , but not always.  For typedefs, we need to use
4312/// 'i' or 'I' instead if encoding a struct field, or a pointer!
4313///
4314void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
4315  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
4316    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
4317      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
4318        PointeeTy = UnsignedIntTy;
4319      else
4320        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
4321          PointeeTy = IntTy;
4322    }
4323  }
4324}
4325
4326void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
4327                                        const FieldDecl *Field) const {
4328  // We follow the behavior of gcc, expanding structures which are
4329  // directly pointed to, and expanding embedded structures. Note that
4330  // these rules are sufficient to prevent recursive encoding of the
4331  // same type.
4332  getObjCEncodingForTypeImpl(T, S, true, true, Field,
4333                             true /* outermost type */);
4334}
4335
4336static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
4337    switch (T->getAs<BuiltinType>()->getKind()) {
4338    default: llvm_unreachable("Unhandled builtin type kind");
4339    case BuiltinType::Void:       return 'v';
4340    case BuiltinType::Bool:       return 'B';
4341    case BuiltinType::Char_U:
4342    case BuiltinType::UChar:      return 'C';
4343    case BuiltinType::UShort:     return 'S';
4344    case BuiltinType::UInt:       return 'I';
4345    case BuiltinType::ULong:
4346        return C->getIntWidth(T) == 32 ? 'L' : 'Q';
4347    case BuiltinType::UInt128:    return 'T';
4348    case BuiltinType::ULongLong:  return 'Q';
4349    case BuiltinType::Char_S:
4350    case BuiltinType::SChar:      return 'c';
4351    case BuiltinType::Short:      return 's';
4352    case BuiltinType::WChar_S:
4353    case BuiltinType::WChar_U:
4354    case BuiltinType::Int:        return 'i';
4355    case BuiltinType::Long:
4356      return C->getIntWidth(T) == 32 ? 'l' : 'q';
4357    case BuiltinType::LongLong:   return 'q';
4358    case BuiltinType::Int128:     return 't';
4359    case BuiltinType::Float:      return 'f';
4360    case BuiltinType::Double:     return 'd';
4361    case BuiltinType::LongDouble: return 'D';
4362    }
4363}
4364
4365static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
4366  EnumDecl *Enum = ET->getDecl();
4367
4368  // The encoding of an non-fixed enum type is always 'i', regardless of size.
4369  if (!Enum->isFixed())
4370    return 'i';
4371
4372  // The encoding of a fixed enum type matches its fixed underlying type.
4373  return ObjCEncodingForPrimitiveKind(C, Enum->getIntegerType());
4374}
4375
4376static void EncodeBitField(const ASTContext *Ctx, std::string& S,
4377                           QualType T, const FieldDecl *FD) {
4378  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
4379  S += 'b';
4380  // The NeXT runtime encodes bit fields as b followed by the number of bits.
4381  // The GNU runtime requires more information; bitfields are encoded as b,
4382  // then the offset (in bits) of the first element, then the type of the
4383  // bitfield, then the size in bits.  For example, in this structure:
4384  //
4385  // struct
4386  // {
4387  //    int integer;
4388  //    int flags:2;
4389  // };
4390  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
4391  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
4392  // information is not especially sensible, but we're stuck with it for
4393  // compatibility with GCC, although providing it breaks anything that
4394  // actually uses runtime introspection and wants to work on both runtimes...
4395  if (!Ctx->getLangOpts().NeXTRuntime) {
4396    const RecordDecl *RD = FD->getParent();
4397    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
4398    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
4399    if (const EnumType *ET = T->getAs<EnumType>())
4400      S += ObjCEncodingForEnumType(Ctx, ET);
4401    else
4402      S += ObjCEncodingForPrimitiveKind(Ctx, T);
4403  }
4404  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
4405}
4406
4407// FIXME: Use SmallString for accumulating string.
4408void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
4409                                            bool ExpandPointedToStructures,
4410                                            bool ExpandStructures,
4411                                            const FieldDecl *FD,
4412                                            bool OutermostType,
4413                                            bool EncodingProperty,
4414                                            bool StructField,
4415                                            bool EncodeBlockParameters,
4416                                            bool EncodeClassNames) const {
4417  if (T->getAs<BuiltinType>()) {
4418    if (FD && FD->isBitField())
4419      return EncodeBitField(this, S, T, FD);
4420    S += ObjCEncodingForPrimitiveKind(this, T);
4421    return;
4422  }
4423
4424  if (const ComplexType *CT = T->getAs<ComplexType>()) {
4425    S += 'j';
4426    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
4427                               false);
4428    return;
4429  }
4430
4431  // encoding for pointer or r3eference types.
4432  QualType PointeeTy;
4433  if (const PointerType *PT = T->getAs<PointerType>()) {
4434    if (PT->isObjCSelType()) {
4435      S += ':';
4436      return;
4437    }
4438    PointeeTy = PT->getPointeeType();
4439  }
4440  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4441    PointeeTy = RT->getPointeeType();
4442  if (!PointeeTy.isNull()) {
4443    bool isReadOnly = false;
4444    // For historical/compatibility reasons, the read-only qualifier of the
4445    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
4446    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
4447    // Also, do not emit the 'r' for anything but the outermost type!
4448    if (isa<TypedefType>(T.getTypePtr())) {
4449      if (OutermostType && T.isConstQualified()) {
4450        isReadOnly = true;
4451        S += 'r';
4452      }
4453    } else if (OutermostType) {
4454      QualType P = PointeeTy;
4455      while (P->getAs<PointerType>())
4456        P = P->getAs<PointerType>()->getPointeeType();
4457      if (P.isConstQualified()) {
4458        isReadOnly = true;
4459        S += 'r';
4460      }
4461    }
4462    if (isReadOnly) {
4463      // Another legacy compatibility encoding. Some ObjC qualifier and type
4464      // combinations need to be rearranged.
4465      // Rewrite "in const" from "nr" to "rn"
4466      if (StringRef(S).endswith("nr"))
4467        S.replace(S.end()-2, S.end(), "rn");
4468    }
4469
4470    if (PointeeTy->isCharType()) {
4471      // char pointer types should be encoded as '*' unless it is a
4472      // type that has been typedef'd to 'BOOL'.
4473      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
4474        S += '*';
4475        return;
4476      }
4477    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
4478      // GCC binary compat: Need to convert "struct objc_class *" to "#".
4479      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
4480        S += '#';
4481        return;
4482      }
4483      // GCC binary compat: Need to convert "struct objc_object *" to "@".
4484      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
4485        S += '@';
4486        return;
4487      }
4488      // fall through...
4489    }
4490    S += '^';
4491    getLegacyIntegralTypeEncoding(PointeeTy);
4492
4493    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
4494                               NULL);
4495    return;
4496  }
4497
4498  if (const ArrayType *AT =
4499      // Ignore type qualifiers etc.
4500        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
4501    if (isa<IncompleteArrayType>(AT) && !StructField) {
4502      // Incomplete arrays are encoded as a pointer to the array element.
4503      S += '^';
4504
4505      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4506                                 false, ExpandStructures, FD);
4507    } else {
4508      S += '[';
4509
4510      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
4511        if (getTypeSize(CAT->getElementType()) == 0)
4512          S += '0';
4513        else
4514          S += llvm::utostr(CAT->getSize().getZExtValue());
4515      } else {
4516        //Variable length arrays are encoded as a regular array with 0 elements.
4517        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
4518               "Unknown array type!");
4519        S += '0';
4520      }
4521
4522      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4523                                 false, ExpandStructures, FD);
4524      S += ']';
4525    }
4526    return;
4527  }
4528
4529  if (T->getAs<FunctionType>()) {
4530    S += '?';
4531    return;
4532  }
4533
4534  if (const RecordType *RTy = T->getAs<RecordType>()) {
4535    RecordDecl *RDecl = RTy->getDecl();
4536    S += RDecl->isUnion() ? '(' : '{';
4537    // Anonymous structures print as '?'
4538    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
4539      S += II->getName();
4540      if (ClassTemplateSpecializationDecl *Spec
4541          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
4542        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
4543        std::string TemplateArgsStr
4544          = TemplateSpecializationType::PrintTemplateArgumentList(
4545                                            TemplateArgs.data(),
4546                                            TemplateArgs.size(),
4547                                            (*this).getPrintingPolicy());
4548
4549        S += TemplateArgsStr;
4550      }
4551    } else {
4552      S += '?';
4553    }
4554    if (ExpandStructures) {
4555      S += '=';
4556      if (!RDecl->isUnion()) {
4557        getObjCEncodingForStructureImpl(RDecl, S, FD);
4558      } else {
4559        for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4560                                     FieldEnd = RDecl->field_end();
4561             Field != FieldEnd; ++Field) {
4562          if (FD) {
4563            S += '"';
4564            S += Field->getNameAsString();
4565            S += '"';
4566          }
4567
4568          // Special case bit-fields.
4569          if (Field->isBitField()) {
4570            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
4571                                       &*Field);
4572          } else {
4573            QualType qt = Field->getType();
4574            getLegacyIntegralTypeEncoding(qt);
4575            getObjCEncodingForTypeImpl(qt, S, false, true,
4576                                       FD, /*OutermostType*/false,
4577                                       /*EncodingProperty*/false,
4578                                       /*StructField*/true);
4579          }
4580        }
4581      }
4582    }
4583    S += RDecl->isUnion() ? ')' : '}';
4584    return;
4585  }
4586
4587  if (const EnumType *ET = T->getAs<EnumType>()) {
4588    if (FD && FD->isBitField())
4589      EncodeBitField(this, S, T, FD);
4590    else
4591      S += ObjCEncodingForEnumType(this, ET);
4592    return;
4593  }
4594
4595  if (const BlockPointerType *BT = T->getAs<BlockPointerType>()) {
4596    S += "@?"; // Unlike a pointer-to-function, which is "^?".
4597    if (EncodeBlockParameters) {
4598      const FunctionType *FT = BT->getPointeeType()->getAs<FunctionType>();
4599
4600      S += '<';
4601      // Block return type
4602      getObjCEncodingForTypeImpl(FT->getResultType(), S,
4603                                 ExpandPointedToStructures, ExpandStructures,
4604                                 FD,
4605                                 false /* OutermostType */,
4606                                 EncodingProperty,
4607                                 false /* StructField */,
4608                                 EncodeBlockParameters,
4609                                 EncodeClassNames);
4610      // Block self
4611      S += "@?";
4612      // Block parameters
4613      if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT)) {
4614        for (FunctionProtoType::arg_type_iterator I = FPT->arg_type_begin(),
4615               E = FPT->arg_type_end(); I && (I != E); ++I) {
4616          getObjCEncodingForTypeImpl(*I, S,
4617                                     ExpandPointedToStructures,
4618                                     ExpandStructures,
4619                                     FD,
4620                                     false /* OutermostType */,
4621                                     EncodingProperty,
4622                                     false /* StructField */,
4623                                     EncodeBlockParameters,
4624                                     EncodeClassNames);
4625        }
4626      }
4627      S += '>';
4628    }
4629    return;
4630  }
4631
4632  // Ignore protocol qualifiers when mangling at this level.
4633  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
4634    T = OT->getBaseType();
4635
4636  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
4637    // @encode(class_name)
4638    ObjCInterfaceDecl *OI = OIT->getDecl();
4639    S += '{';
4640    const IdentifierInfo *II = OI->getIdentifier();
4641    S += II->getName();
4642    S += '=';
4643    SmallVector<const ObjCIvarDecl*, 32> Ivars;
4644    DeepCollectObjCIvars(OI, true, Ivars);
4645    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
4646      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
4647      if (Field->isBitField())
4648        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
4649      else
4650        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
4651    }
4652    S += '}';
4653    return;
4654  }
4655
4656  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
4657    if (OPT->isObjCIdType()) {
4658      S += '@';
4659      return;
4660    }
4661
4662    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
4663      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
4664      // Since this is a binary compatibility issue, need to consult with runtime
4665      // folks. Fortunately, this is a *very* obsure construct.
4666      S += '#';
4667      return;
4668    }
4669
4670    if (OPT->isObjCQualifiedIdType()) {
4671      getObjCEncodingForTypeImpl(getObjCIdType(), S,
4672                                 ExpandPointedToStructures,
4673                                 ExpandStructures, FD);
4674      if (FD || EncodingProperty || EncodeClassNames) {
4675        // Note that we do extended encoding of protocol qualifer list
4676        // Only when doing ivar or property encoding.
4677        S += '"';
4678        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4679             E = OPT->qual_end(); I != E; ++I) {
4680          S += '<';
4681          S += (*I)->getNameAsString();
4682          S += '>';
4683        }
4684        S += '"';
4685      }
4686      return;
4687    }
4688
4689    QualType PointeeTy = OPT->getPointeeType();
4690    if (!EncodingProperty &&
4691        isa<TypedefType>(PointeeTy.getTypePtr())) {
4692      // Another historical/compatibility reason.
4693      // We encode the underlying type which comes out as
4694      // {...};
4695      S += '^';
4696      getObjCEncodingForTypeImpl(PointeeTy, S,
4697                                 false, ExpandPointedToStructures,
4698                                 NULL);
4699      return;
4700    }
4701
4702    S += '@';
4703    if (OPT->getInterfaceDecl() &&
4704        (FD || EncodingProperty || EncodeClassNames)) {
4705      S += '"';
4706      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4707      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4708           E = OPT->qual_end(); I != E; ++I) {
4709        S += '<';
4710        S += (*I)->getNameAsString();
4711        S += '>';
4712      }
4713      S += '"';
4714    }
4715    return;
4716  }
4717
4718  // gcc just blithely ignores member pointers.
4719  // TODO: maybe there should be a mangling for these
4720  if (T->getAs<MemberPointerType>())
4721    return;
4722
4723  if (T->isVectorType()) {
4724    // This matches gcc's encoding, even though technically it is
4725    // insufficient.
4726    // FIXME. We should do a better job than gcc.
4727    return;
4728  }
4729
4730  llvm_unreachable("@encode for type not implemented!");
4731}
4732
4733void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
4734                                                 std::string &S,
4735                                                 const FieldDecl *FD,
4736                                                 bool includeVBases) const {
4737  assert(RDecl && "Expected non-null RecordDecl");
4738  assert(!RDecl->isUnion() && "Should not be called for unions");
4739  if (!RDecl->getDefinition())
4740    return;
4741
4742  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
4743  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
4744  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
4745
4746  if (CXXRec) {
4747    for (CXXRecordDecl::base_class_iterator
4748           BI = CXXRec->bases_begin(),
4749           BE = CXXRec->bases_end(); BI != BE; ++BI) {
4750      if (!BI->isVirtual()) {
4751        CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4752        if (base->isEmpty())
4753          continue;
4754        uint64_t offs = layout.getBaseClassOffsetInBits(base);
4755        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4756                                  std::make_pair(offs, base));
4757      }
4758    }
4759  }
4760
4761  unsigned i = 0;
4762  for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4763                               FieldEnd = RDecl->field_end();
4764       Field != FieldEnd; ++Field, ++i) {
4765    uint64_t offs = layout.getFieldOffset(i);
4766    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4767                              std::make_pair(offs, &*Field));
4768  }
4769
4770  if (CXXRec && includeVBases) {
4771    for (CXXRecordDecl::base_class_iterator
4772           BI = CXXRec->vbases_begin(),
4773           BE = CXXRec->vbases_end(); BI != BE; ++BI) {
4774      CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4775      if (base->isEmpty())
4776        continue;
4777      uint64_t offs = layout.getVBaseClassOffsetInBits(base);
4778      if (FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
4779        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
4780                                  std::make_pair(offs, base));
4781    }
4782  }
4783
4784  CharUnits size;
4785  if (CXXRec) {
4786    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
4787  } else {
4788    size = layout.getSize();
4789  }
4790
4791  uint64_t CurOffs = 0;
4792  std::multimap<uint64_t, NamedDecl *>::iterator
4793    CurLayObj = FieldOrBaseOffsets.begin();
4794
4795  if (CXXRec && CXXRec->isDynamicClass() &&
4796      (CurLayObj == FieldOrBaseOffsets.end() || CurLayObj->first != 0)) {
4797    if (FD) {
4798      S += "\"_vptr$";
4799      std::string recname = CXXRec->getNameAsString();
4800      if (recname.empty()) recname = "?";
4801      S += recname;
4802      S += '"';
4803    }
4804    S += "^^?";
4805    CurOffs += getTypeSize(VoidPtrTy);
4806  }
4807
4808  if (!RDecl->hasFlexibleArrayMember()) {
4809    // Mark the end of the structure.
4810    uint64_t offs = toBits(size);
4811    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4812                              std::make_pair(offs, (NamedDecl*)0));
4813  }
4814
4815  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
4816    assert(CurOffs <= CurLayObj->first);
4817
4818    if (CurOffs < CurLayObj->first) {
4819      uint64_t padding = CurLayObj->first - CurOffs;
4820      // FIXME: There doesn't seem to be a way to indicate in the encoding that
4821      // packing/alignment of members is different that normal, in which case
4822      // the encoding will be out-of-sync with the real layout.
4823      // If the runtime switches to just consider the size of types without
4824      // taking into account alignment, we could make padding explicit in the
4825      // encoding (e.g. using arrays of chars). The encoding strings would be
4826      // longer then though.
4827      CurOffs += padding;
4828    }
4829
4830    NamedDecl *dcl = CurLayObj->second;
4831    if (dcl == 0)
4832      break; // reached end of structure.
4833
4834    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
4835      // We expand the bases without their virtual bases since those are going
4836      // in the initial structure. Note that this differs from gcc which
4837      // expands virtual bases each time one is encountered in the hierarchy,
4838      // making the encoding type bigger than it really is.
4839      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false);
4840      assert(!base->isEmpty());
4841      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
4842    } else {
4843      FieldDecl *field = cast<FieldDecl>(dcl);
4844      if (FD) {
4845        S += '"';
4846        S += field->getNameAsString();
4847        S += '"';
4848      }
4849
4850      if (field->isBitField()) {
4851        EncodeBitField(this, S, field->getType(), field);
4852        CurOffs += field->getBitWidthValue(*this);
4853      } else {
4854        QualType qt = field->getType();
4855        getLegacyIntegralTypeEncoding(qt);
4856        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
4857                                   /*OutermostType*/false,
4858                                   /*EncodingProperty*/false,
4859                                   /*StructField*/true);
4860        CurOffs += getTypeSize(field->getType());
4861      }
4862    }
4863  }
4864}
4865
4866void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4867                                                 std::string& S) const {
4868  if (QT & Decl::OBJC_TQ_In)
4869    S += 'n';
4870  if (QT & Decl::OBJC_TQ_Inout)
4871    S += 'N';
4872  if (QT & Decl::OBJC_TQ_Out)
4873    S += 'o';
4874  if (QT & Decl::OBJC_TQ_Bycopy)
4875    S += 'O';
4876  if (QT & Decl::OBJC_TQ_Byref)
4877    S += 'R';
4878  if (QT & Decl::OBJC_TQ_Oneway)
4879    S += 'V';
4880}
4881
4882void ASTContext::setBuiltinVaListType(QualType T) {
4883  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4884
4885  BuiltinVaListType = T;
4886}
4887
4888TypedefDecl *ASTContext::getObjCIdDecl() const {
4889  if (!ObjCIdDecl) {
4890    QualType T = getObjCObjectType(ObjCBuiltinIdTy, 0, 0);
4891    T = getObjCObjectPointerType(T);
4892    TypeSourceInfo *IdInfo = getTrivialTypeSourceInfo(T);
4893    ObjCIdDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4894                                     getTranslationUnitDecl(),
4895                                     SourceLocation(), SourceLocation(),
4896                                     &Idents.get("id"), IdInfo);
4897  }
4898
4899  return ObjCIdDecl;
4900}
4901
4902TypedefDecl *ASTContext::getObjCSelDecl() const {
4903  if (!ObjCSelDecl) {
4904    QualType SelT = getPointerType(ObjCBuiltinSelTy);
4905    TypeSourceInfo *SelInfo = getTrivialTypeSourceInfo(SelT);
4906    ObjCSelDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4907                                      getTranslationUnitDecl(),
4908                                      SourceLocation(), SourceLocation(),
4909                                      &Idents.get("SEL"), SelInfo);
4910  }
4911  return ObjCSelDecl;
4912}
4913
4914TypedefDecl *ASTContext::getObjCClassDecl() const {
4915  if (!ObjCClassDecl) {
4916    QualType T = getObjCObjectType(ObjCBuiltinClassTy, 0, 0);
4917    T = getObjCObjectPointerType(T);
4918    TypeSourceInfo *ClassInfo = getTrivialTypeSourceInfo(T);
4919    ObjCClassDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4920                                        getTranslationUnitDecl(),
4921                                        SourceLocation(), SourceLocation(),
4922                                        &Idents.get("Class"), ClassInfo);
4923  }
4924
4925  return ObjCClassDecl;
4926}
4927
4928ObjCInterfaceDecl *ASTContext::getObjCProtocolDecl() const {
4929  if (!ObjCProtocolClassDecl) {
4930    ObjCProtocolClassDecl
4931      = ObjCInterfaceDecl::Create(*this, getTranslationUnitDecl(),
4932                                  SourceLocation(),
4933                                  &Idents.get("Protocol"),
4934                                  /*PrevDecl=*/0,
4935                                  SourceLocation(), true);
4936  }
4937
4938  return ObjCProtocolClassDecl;
4939}
4940
4941void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4942  assert(ObjCConstantStringType.isNull() &&
4943         "'NSConstantString' type already set!");
4944
4945  ObjCConstantStringType = getObjCInterfaceType(Decl);
4946}
4947
4948/// \brief Retrieve the template name that corresponds to a non-empty
4949/// lookup.
4950TemplateName
4951ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4952                                      UnresolvedSetIterator End) const {
4953  unsigned size = End - Begin;
4954  assert(size > 1 && "set is not overloaded!");
4955
4956  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4957                          size * sizeof(FunctionTemplateDecl*));
4958  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4959
4960  NamedDecl **Storage = OT->getStorage();
4961  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4962    NamedDecl *D = *I;
4963    assert(isa<FunctionTemplateDecl>(D) ||
4964           (isa<UsingShadowDecl>(D) &&
4965            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4966    *Storage++ = D;
4967  }
4968
4969  return TemplateName(OT);
4970}
4971
4972/// \brief Retrieve the template name that represents a qualified
4973/// template name such as \c std::vector.
4974TemplateName
4975ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4976                                     bool TemplateKeyword,
4977                                     TemplateDecl *Template) const {
4978  assert(NNS && "Missing nested-name-specifier in qualified template name");
4979
4980  // FIXME: Canonicalization?
4981  llvm::FoldingSetNodeID ID;
4982  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4983
4984  void *InsertPos = 0;
4985  QualifiedTemplateName *QTN =
4986    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4987  if (!QTN) {
4988    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4989    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4990  }
4991
4992  return TemplateName(QTN);
4993}
4994
4995/// \brief Retrieve the template name that represents a dependent
4996/// template name such as \c MetaFun::template apply.
4997TemplateName
4998ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4999                                     const IdentifierInfo *Name) const {
5000  assert((!NNS || NNS->isDependent()) &&
5001         "Nested name specifier must be dependent");
5002
5003  llvm::FoldingSetNodeID ID;
5004  DependentTemplateName::Profile(ID, NNS, Name);
5005
5006  void *InsertPos = 0;
5007  DependentTemplateName *QTN =
5008    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5009
5010  if (QTN)
5011    return TemplateName(QTN);
5012
5013  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
5014  if (CanonNNS == NNS) {
5015    QTN = new (*this,4) DependentTemplateName(NNS, Name);
5016  } else {
5017    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
5018    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
5019    DependentTemplateName *CheckQTN =
5020      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5021    assert(!CheckQTN && "Dependent type name canonicalization broken");
5022    (void)CheckQTN;
5023  }
5024
5025  DependentTemplateNames.InsertNode(QTN, InsertPos);
5026  return TemplateName(QTN);
5027}
5028
5029/// \brief Retrieve the template name that represents a dependent
5030/// template name such as \c MetaFun::template operator+.
5031TemplateName
5032ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
5033                                     OverloadedOperatorKind Operator) const {
5034  assert((!NNS || NNS->isDependent()) &&
5035         "Nested name specifier must be dependent");
5036
5037  llvm::FoldingSetNodeID ID;
5038  DependentTemplateName::Profile(ID, NNS, Operator);
5039
5040  void *InsertPos = 0;
5041  DependentTemplateName *QTN
5042    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5043
5044  if (QTN)
5045    return TemplateName(QTN);
5046
5047  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
5048  if (CanonNNS == NNS) {
5049    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
5050  } else {
5051    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
5052    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
5053
5054    DependentTemplateName *CheckQTN
5055      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5056    assert(!CheckQTN && "Dependent template name canonicalization broken");
5057    (void)CheckQTN;
5058  }
5059
5060  DependentTemplateNames.InsertNode(QTN, InsertPos);
5061  return TemplateName(QTN);
5062}
5063
5064TemplateName
5065ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
5066                                         TemplateName replacement) const {
5067  llvm::FoldingSetNodeID ID;
5068  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
5069
5070  void *insertPos = 0;
5071  SubstTemplateTemplateParmStorage *subst
5072    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
5073
5074  if (!subst) {
5075    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
5076    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
5077  }
5078
5079  return TemplateName(subst);
5080}
5081
5082TemplateName
5083ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
5084                                       const TemplateArgument &ArgPack) const {
5085  ASTContext &Self = const_cast<ASTContext &>(*this);
5086  llvm::FoldingSetNodeID ID;
5087  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
5088
5089  void *InsertPos = 0;
5090  SubstTemplateTemplateParmPackStorage *Subst
5091    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
5092
5093  if (!Subst) {
5094    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
5095                                                           ArgPack.pack_size(),
5096                                                         ArgPack.pack_begin());
5097    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
5098  }
5099
5100  return TemplateName(Subst);
5101}
5102
5103/// getFromTargetType - Given one of the integer types provided by
5104/// TargetInfo, produce the corresponding type. The unsigned @p Type
5105/// is actually a value of type @c TargetInfo::IntType.
5106CanQualType ASTContext::getFromTargetType(unsigned Type) const {
5107  switch (Type) {
5108  case TargetInfo::NoInt: return CanQualType();
5109  case TargetInfo::SignedShort: return ShortTy;
5110  case TargetInfo::UnsignedShort: return UnsignedShortTy;
5111  case TargetInfo::SignedInt: return IntTy;
5112  case TargetInfo::UnsignedInt: return UnsignedIntTy;
5113  case TargetInfo::SignedLong: return LongTy;
5114  case TargetInfo::UnsignedLong: return UnsignedLongTy;
5115  case TargetInfo::SignedLongLong: return LongLongTy;
5116  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
5117  }
5118
5119  llvm_unreachable("Unhandled TargetInfo::IntType value");
5120}
5121
5122//===----------------------------------------------------------------------===//
5123//                        Type Predicates.
5124//===----------------------------------------------------------------------===//
5125
5126/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
5127/// garbage collection attribute.
5128///
5129Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
5130  if (getLangOpts().getGC() == LangOptions::NonGC)
5131    return Qualifiers::GCNone;
5132
5133  assert(getLangOpts().ObjC1);
5134  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
5135
5136  // Default behaviour under objective-C's gc is for ObjC pointers
5137  // (or pointers to them) be treated as though they were declared
5138  // as __strong.
5139  if (GCAttrs == Qualifiers::GCNone) {
5140    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
5141      return Qualifiers::Strong;
5142    else if (Ty->isPointerType())
5143      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
5144  } else {
5145    // It's not valid to set GC attributes on anything that isn't a
5146    // pointer.
5147#ifndef NDEBUG
5148    QualType CT = Ty->getCanonicalTypeInternal();
5149    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
5150      CT = AT->getElementType();
5151    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
5152#endif
5153  }
5154  return GCAttrs;
5155}
5156
5157//===----------------------------------------------------------------------===//
5158//                        Type Compatibility Testing
5159//===----------------------------------------------------------------------===//
5160
5161/// areCompatVectorTypes - Return true if the two specified vector types are
5162/// compatible.
5163static bool areCompatVectorTypes(const VectorType *LHS,
5164                                 const VectorType *RHS) {
5165  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
5166  return LHS->getElementType() == RHS->getElementType() &&
5167         LHS->getNumElements() == RHS->getNumElements();
5168}
5169
5170bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
5171                                          QualType SecondVec) {
5172  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
5173  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
5174
5175  if (hasSameUnqualifiedType(FirstVec, SecondVec))
5176    return true;
5177
5178  // Treat Neon vector types and most AltiVec vector types as if they are the
5179  // equivalent GCC vector types.
5180  const VectorType *First = FirstVec->getAs<VectorType>();
5181  const VectorType *Second = SecondVec->getAs<VectorType>();
5182  if (First->getNumElements() == Second->getNumElements() &&
5183      hasSameType(First->getElementType(), Second->getElementType()) &&
5184      First->getVectorKind() != VectorType::AltiVecPixel &&
5185      First->getVectorKind() != VectorType::AltiVecBool &&
5186      Second->getVectorKind() != VectorType::AltiVecPixel &&
5187      Second->getVectorKind() != VectorType::AltiVecBool)
5188    return true;
5189
5190  return false;
5191}
5192
5193//===----------------------------------------------------------------------===//
5194// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
5195//===----------------------------------------------------------------------===//
5196
5197/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
5198/// inheritance hierarchy of 'rProto'.
5199bool
5200ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
5201                                           ObjCProtocolDecl *rProto) const {
5202  if (declaresSameEntity(lProto, rProto))
5203    return true;
5204  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
5205       E = rProto->protocol_end(); PI != E; ++PI)
5206    if (ProtocolCompatibleWithProtocol(lProto, *PI))
5207      return true;
5208  return false;
5209}
5210
5211/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
5212/// return true if lhs's protocols conform to rhs's protocol; false
5213/// otherwise.
5214bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
5215  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
5216    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
5217  return false;
5218}
5219
5220/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
5221/// Class<p1, ...>.
5222bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
5223                                                      QualType rhs) {
5224  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
5225  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5226  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
5227
5228  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5229       E = lhsQID->qual_end(); I != E; ++I) {
5230    bool match = false;
5231    ObjCProtocolDecl *lhsProto = *I;
5232    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5233         E = rhsOPT->qual_end(); J != E; ++J) {
5234      ObjCProtocolDecl *rhsProto = *J;
5235      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
5236        match = true;
5237        break;
5238      }
5239    }
5240    if (!match)
5241      return false;
5242  }
5243  return true;
5244}
5245
5246/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
5247/// ObjCQualifiedIDType.
5248bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
5249                                                   bool compare) {
5250  // Allow id<P..> and an 'id' or void* type in all cases.
5251  if (lhs->isVoidPointerType() ||
5252      lhs->isObjCIdType() || lhs->isObjCClassType())
5253    return true;
5254  else if (rhs->isVoidPointerType() ||
5255           rhs->isObjCIdType() || rhs->isObjCClassType())
5256    return true;
5257
5258  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
5259    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5260
5261    if (!rhsOPT) return false;
5262
5263    if (rhsOPT->qual_empty()) {
5264      // If the RHS is a unqualified interface pointer "NSString*",
5265      // make sure we check the class hierarchy.
5266      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5267        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5268             E = lhsQID->qual_end(); I != E; ++I) {
5269          // when comparing an id<P> on lhs with a static type on rhs,
5270          // see if static class implements all of id's protocols, directly or
5271          // through its super class and categories.
5272          if (!rhsID->ClassImplementsProtocol(*I, true))
5273            return false;
5274        }
5275      }
5276      // If there are no qualifiers and no interface, we have an 'id'.
5277      return true;
5278    }
5279    // Both the right and left sides have qualifiers.
5280    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5281         E = lhsQID->qual_end(); I != E; ++I) {
5282      ObjCProtocolDecl *lhsProto = *I;
5283      bool match = false;
5284
5285      // when comparing an id<P> on lhs with a static type on rhs,
5286      // see if static class implements all of id's protocols, directly or
5287      // through its super class and categories.
5288      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5289           E = rhsOPT->qual_end(); J != E; ++J) {
5290        ObjCProtocolDecl *rhsProto = *J;
5291        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5292            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5293          match = true;
5294          break;
5295        }
5296      }
5297      // If the RHS is a qualified interface pointer "NSString<P>*",
5298      // make sure we check the class hierarchy.
5299      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5300        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5301             E = lhsQID->qual_end(); I != E; ++I) {
5302          // when comparing an id<P> on lhs with a static type on rhs,
5303          // see if static class implements all of id's protocols, directly or
5304          // through its super class and categories.
5305          if (rhsID->ClassImplementsProtocol(*I, true)) {
5306            match = true;
5307            break;
5308          }
5309        }
5310      }
5311      if (!match)
5312        return false;
5313    }
5314
5315    return true;
5316  }
5317
5318  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
5319  assert(rhsQID && "One of the LHS/RHS should be id<x>");
5320
5321  if (const ObjCObjectPointerType *lhsOPT =
5322        lhs->getAsObjCInterfacePointerType()) {
5323    // If both the right and left sides have qualifiers.
5324    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
5325         E = lhsOPT->qual_end(); I != E; ++I) {
5326      ObjCProtocolDecl *lhsProto = *I;
5327      bool match = false;
5328
5329      // when comparing an id<P> on rhs with a static type on lhs,
5330      // see if static class implements all of id's protocols, directly or
5331      // through its super class and categories.
5332      // First, lhs protocols in the qualifier list must be found, direct
5333      // or indirect in rhs's qualifier list or it is a mismatch.
5334      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5335           E = rhsQID->qual_end(); J != E; ++J) {
5336        ObjCProtocolDecl *rhsProto = *J;
5337        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5338            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5339          match = true;
5340          break;
5341        }
5342      }
5343      if (!match)
5344        return false;
5345    }
5346
5347    // Static class's protocols, or its super class or category protocols
5348    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
5349    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
5350      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5351      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
5352      // This is rather dubious but matches gcc's behavior. If lhs has
5353      // no type qualifier and its class has no static protocol(s)
5354      // assume that it is mismatch.
5355      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
5356        return false;
5357      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5358           LHSInheritedProtocols.begin(),
5359           E = LHSInheritedProtocols.end(); I != E; ++I) {
5360        bool match = false;
5361        ObjCProtocolDecl *lhsProto = (*I);
5362        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5363             E = rhsQID->qual_end(); J != E; ++J) {
5364          ObjCProtocolDecl *rhsProto = *J;
5365          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5366              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5367            match = true;
5368            break;
5369          }
5370        }
5371        if (!match)
5372          return false;
5373      }
5374    }
5375    return true;
5376  }
5377  return false;
5378}
5379
5380/// canAssignObjCInterfaces - Return true if the two interface types are
5381/// compatible for assignment from RHS to LHS.  This handles validation of any
5382/// protocol qualifiers on the LHS or RHS.
5383///
5384bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
5385                                         const ObjCObjectPointerType *RHSOPT) {
5386  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5387  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5388
5389  // If either type represents the built-in 'id' or 'Class' types, return true.
5390  if (LHS->isObjCUnqualifiedIdOrClass() ||
5391      RHS->isObjCUnqualifiedIdOrClass())
5392    return true;
5393
5394  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
5395    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5396                                             QualType(RHSOPT,0),
5397                                             false);
5398
5399  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
5400    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
5401                                                QualType(RHSOPT,0));
5402
5403  // If we have 2 user-defined types, fall into that path.
5404  if (LHS->getInterface() && RHS->getInterface())
5405    return canAssignObjCInterfaces(LHS, RHS);
5406
5407  return false;
5408}
5409
5410/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
5411/// for providing type-safety for objective-c pointers used to pass/return
5412/// arguments in block literals. When passed as arguments, passing 'A*' where
5413/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
5414/// not OK. For the return type, the opposite is not OK.
5415bool ASTContext::canAssignObjCInterfacesInBlockPointer(
5416                                         const ObjCObjectPointerType *LHSOPT,
5417                                         const ObjCObjectPointerType *RHSOPT,
5418                                         bool BlockReturnType) {
5419  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
5420    return true;
5421
5422  if (LHSOPT->isObjCBuiltinType()) {
5423    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
5424  }
5425
5426  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
5427    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5428                                             QualType(RHSOPT,0),
5429                                             false);
5430
5431  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
5432  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
5433  if (LHS && RHS)  { // We have 2 user-defined types.
5434    if (LHS != RHS) {
5435      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
5436        return BlockReturnType;
5437      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
5438        return !BlockReturnType;
5439    }
5440    else
5441      return true;
5442  }
5443  return false;
5444}
5445
5446/// getIntersectionOfProtocols - This routine finds the intersection of set
5447/// of protocols inherited from two distinct objective-c pointer objects.
5448/// It is used to build composite qualifier list of the composite type of
5449/// the conditional expression involving two objective-c pointer objects.
5450static
5451void getIntersectionOfProtocols(ASTContext &Context,
5452                                const ObjCObjectPointerType *LHSOPT,
5453                                const ObjCObjectPointerType *RHSOPT,
5454      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
5455
5456  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5457  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5458  assert(LHS->getInterface() && "LHS must have an interface base");
5459  assert(RHS->getInterface() && "RHS must have an interface base");
5460
5461  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
5462  unsigned LHSNumProtocols = LHS->getNumProtocols();
5463  if (LHSNumProtocols > 0)
5464    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
5465  else {
5466    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5467    Context.CollectInheritedProtocols(LHS->getInterface(),
5468                                      LHSInheritedProtocols);
5469    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
5470                                LHSInheritedProtocols.end());
5471  }
5472
5473  unsigned RHSNumProtocols = RHS->getNumProtocols();
5474  if (RHSNumProtocols > 0) {
5475    ObjCProtocolDecl **RHSProtocols =
5476      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
5477    for (unsigned i = 0; i < RHSNumProtocols; ++i)
5478      if (InheritedProtocolSet.count(RHSProtocols[i]))
5479        IntersectionOfProtocols.push_back(RHSProtocols[i]);
5480  } else {
5481    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
5482    Context.CollectInheritedProtocols(RHS->getInterface(),
5483                                      RHSInheritedProtocols);
5484    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5485         RHSInheritedProtocols.begin(),
5486         E = RHSInheritedProtocols.end(); I != E; ++I)
5487      if (InheritedProtocolSet.count((*I)))
5488        IntersectionOfProtocols.push_back((*I));
5489  }
5490}
5491
5492/// areCommonBaseCompatible - Returns common base class of the two classes if
5493/// one found. Note that this is O'2 algorithm. But it will be called as the
5494/// last type comparison in a ?-exp of ObjC pointer types before a
5495/// warning is issued. So, its invokation is extremely rare.
5496QualType ASTContext::areCommonBaseCompatible(
5497                                          const ObjCObjectPointerType *Lptr,
5498                                          const ObjCObjectPointerType *Rptr) {
5499  const ObjCObjectType *LHS = Lptr->getObjectType();
5500  const ObjCObjectType *RHS = Rptr->getObjectType();
5501  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
5502  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
5503  if (!LDecl || !RDecl || (declaresSameEntity(LDecl, RDecl)))
5504    return QualType();
5505
5506  do {
5507    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
5508    if (canAssignObjCInterfaces(LHS, RHS)) {
5509      SmallVector<ObjCProtocolDecl *, 8> Protocols;
5510      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
5511
5512      QualType Result = QualType(LHS, 0);
5513      if (!Protocols.empty())
5514        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
5515      Result = getObjCObjectPointerType(Result);
5516      return Result;
5517    }
5518  } while ((LDecl = LDecl->getSuperClass()));
5519
5520  return QualType();
5521}
5522
5523bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
5524                                         const ObjCObjectType *RHS) {
5525  assert(LHS->getInterface() && "LHS is not an interface type");
5526  assert(RHS->getInterface() && "RHS is not an interface type");
5527
5528  // Verify that the base decls are compatible: the RHS must be a subclass of
5529  // the LHS.
5530  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
5531    return false;
5532
5533  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
5534  // protocol qualified at all, then we are good.
5535  if (LHS->getNumProtocols() == 0)
5536    return true;
5537
5538  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't,
5539  // more detailed analysis is required.
5540  if (RHS->getNumProtocols() == 0) {
5541    // OK, if LHS is a superclass of RHS *and*
5542    // this superclass is assignment compatible with LHS.
5543    // false otherwise.
5544    bool IsSuperClass =
5545      LHS->getInterface()->isSuperClassOf(RHS->getInterface());
5546    if (IsSuperClass) {
5547      // OK if conversion of LHS to SuperClass results in narrowing of types
5548      // ; i.e., SuperClass may implement at least one of the protocols
5549      // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
5550      // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
5551      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
5552      CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
5553      // If super class has no protocols, it is not a match.
5554      if (SuperClassInheritedProtocols.empty())
5555        return false;
5556
5557      for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5558           LHSPE = LHS->qual_end();
5559           LHSPI != LHSPE; LHSPI++) {
5560        bool SuperImplementsProtocol = false;
5561        ObjCProtocolDecl *LHSProto = (*LHSPI);
5562
5563        for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5564             SuperClassInheritedProtocols.begin(),
5565             E = SuperClassInheritedProtocols.end(); I != E; ++I) {
5566          ObjCProtocolDecl *SuperClassProto = (*I);
5567          if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
5568            SuperImplementsProtocol = true;
5569            break;
5570          }
5571        }
5572        if (!SuperImplementsProtocol)
5573          return false;
5574      }
5575      return true;
5576    }
5577    return false;
5578  }
5579
5580  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5581                                     LHSPE = LHS->qual_end();
5582       LHSPI != LHSPE; LHSPI++) {
5583    bool RHSImplementsProtocol = false;
5584
5585    // If the RHS doesn't implement the protocol on the left, the types
5586    // are incompatible.
5587    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
5588                                       RHSPE = RHS->qual_end();
5589         RHSPI != RHSPE; RHSPI++) {
5590      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
5591        RHSImplementsProtocol = true;
5592        break;
5593      }
5594    }
5595    // FIXME: For better diagnostics, consider passing back the protocol name.
5596    if (!RHSImplementsProtocol)
5597      return false;
5598  }
5599  // The RHS implements all protocols listed on the LHS.
5600  return true;
5601}
5602
5603bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
5604  // get the "pointed to" types
5605  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
5606  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
5607
5608  if (!LHSOPT || !RHSOPT)
5609    return false;
5610
5611  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
5612         canAssignObjCInterfaces(RHSOPT, LHSOPT);
5613}
5614
5615bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
5616  return canAssignObjCInterfaces(
5617                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
5618                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
5619}
5620
5621/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
5622/// both shall have the identically qualified version of a compatible type.
5623/// C99 6.2.7p1: Two types have compatible types if their types are the
5624/// same. See 6.7.[2,3,5] for additional rules.
5625bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
5626                                    bool CompareUnqualified) {
5627  if (getLangOpts().CPlusPlus)
5628    return hasSameType(LHS, RHS);
5629
5630  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
5631}
5632
5633bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
5634  return typesAreCompatible(LHS, RHS);
5635}
5636
5637bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
5638  return !mergeTypes(LHS, RHS, true).isNull();
5639}
5640
5641/// mergeTransparentUnionType - if T is a transparent union type and a member
5642/// of T is compatible with SubType, return the merged type, else return
5643/// QualType()
5644QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
5645                                               bool OfBlockPointer,
5646                                               bool Unqualified) {
5647  if (const RecordType *UT = T->getAsUnionType()) {
5648    RecordDecl *UD = UT->getDecl();
5649    if (UD->hasAttr<TransparentUnionAttr>()) {
5650      for (RecordDecl::field_iterator it = UD->field_begin(),
5651           itend = UD->field_end(); it != itend; ++it) {
5652        QualType ET = it->getType().getUnqualifiedType();
5653        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
5654        if (!MT.isNull())
5655          return MT;
5656      }
5657    }
5658  }
5659
5660  return QualType();
5661}
5662
5663/// mergeFunctionArgumentTypes - merge two types which appear as function
5664/// argument types
5665QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
5666                                                bool OfBlockPointer,
5667                                                bool Unqualified) {
5668  // GNU extension: two types are compatible if they appear as a function
5669  // argument, one of the types is a transparent union type and the other
5670  // type is compatible with a union member
5671  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
5672                                              Unqualified);
5673  if (!lmerge.isNull())
5674    return lmerge;
5675
5676  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
5677                                              Unqualified);
5678  if (!rmerge.isNull())
5679    return rmerge;
5680
5681  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
5682}
5683
5684QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
5685                                        bool OfBlockPointer,
5686                                        bool Unqualified) {
5687  const FunctionType *lbase = lhs->getAs<FunctionType>();
5688  const FunctionType *rbase = rhs->getAs<FunctionType>();
5689  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
5690  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
5691  bool allLTypes = true;
5692  bool allRTypes = true;
5693
5694  // Check return type
5695  QualType retType;
5696  if (OfBlockPointer) {
5697    QualType RHS = rbase->getResultType();
5698    QualType LHS = lbase->getResultType();
5699    bool UnqualifiedResult = Unqualified;
5700    if (!UnqualifiedResult)
5701      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
5702    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
5703  }
5704  else
5705    retType = mergeTypes(lbase->getResultType(), rbase->getResultType(), false,
5706                         Unqualified);
5707  if (retType.isNull()) return QualType();
5708
5709  if (Unqualified)
5710    retType = retType.getUnqualifiedType();
5711
5712  CanQualType LRetType = getCanonicalType(lbase->getResultType());
5713  CanQualType RRetType = getCanonicalType(rbase->getResultType());
5714  if (Unqualified) {
5715    LRetType = LRetType.getUnqualifiedType();
5716    RRetType = RRetType.getUnqualifiedType();
5717  }
5718
5719  if (getCanonicalType(retType) != LRetType)
5720    allLTypes = false;
5721  if (getCanonicalType(retType) != RRetType)
5722    allRTypes = false;
5723
5724  // FIXME: double check this
5725  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
5726  //                           rbase->getRegParmAttr() != 0 &&
5727  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
5728  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
5729  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
5730
5731  // Compatible functions must have compatible calling conventions
5732  if (!isSameCallConv(lbaseInfo.getCC(), rbaseInfo.getCC()))
5733    return QualType();
5734
5735  // Regparm is part of the calling convention.
5736  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
5737    return QualType();
5738  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
5739    return QualType();
5740
5741  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
5742    return QualType();
5743
5744  // functypes which return are preferred over those that do not.
5745  if (lbaseInfo.getNoReturn() && !rbaseInfo.getNoReturn())
5746    allLTypes = false;
5747  else if (!lbaseInfo.getNoReturn() && rbaseInfo.getNoReturn())
5748    allRTypes = false;
5749  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
5750  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
5751
5752  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
5753
5754  if (lproto && rproto) { // two C99 style function prototypes
5755    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
5756           "C++ shouldn't be here");
5757    unsigned lproto_nargs = lproto->getNumArgs();
5758    unsigned rproto_nargs = rproto->getNumArgs();
5759
5760    // Compatible functions must have the same number of arguments
5761    if (lproto_nargs != rproto_nargs)
5762      return QualType();
5763
5764    // Variadic and non-variadic functions aren't compatible
5765    if (lproto->isVariadic() != rproto->isVariadic())
5766      return QualType();
5767
5768    if (lproto->getTypeQuals() != rproto->getTypeQuals())
5769      return QualType();
5770
5771    if (LangOpts.ObjCAutoRefCount &&
5772        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
5773      return QualType();
5774
5775    // Check argument compatibility
5776    SmallVector<QualType, 10> types;
5777    for (unsigned i = 0; i < lproto_nargs; i++) {
5778      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
5779      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
5780      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
5781                                                    OfBlockPointer,
5782                                                    Unqualified);
5783      if (argtype.isNull()) return QualType();
5784
5785      if (Unqualified)
5786        argtype = argtype.getUnqualifiedType();
5787
5788      types.push_back(argtype);
5789      if (Unqualified) {
5790        largtype = largtype.getUnqualifiedType();
5791        rargtype = rargtype.getUnqualifiedType();
5792      }
5793
5794      if (getCanonicalType(argtype) != getCanonicalType(largtype))
5795        allLTypes = false;
5796      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
5797        allRTypes = false;
5798    }
5799
5800    if (allLTypes) return lhs;
5801    if (allRTypes) return rhs;
5802
5803    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
5804    EPI.ExtInfo = einfo;
5805    return getFunctionType(retType, types.begin(), types.size(), EPI);
5806  }
5807
5808  if (lproto) allRTypes = false;
5809  if (rproto) allLTypes = false;
5810
5811  const FunctionProtoType *proto = lproto ? lproto : rproto;
5812  if (proto) {
5813    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
5814    if (proto->isVariadic()) return QualType();
5815    // Check that the types are compatible with the types that
5816    // would result from default argument promotions (C99 6.7.5.3p15).
5817    // The only types actually affected are promotable integer
5818    // types and floats, which would be passed as a different
5819    // type depending on whether the prototype is visible.
5820    unsigned proto_nargs = proto->getNumArgs();
5821    for (unsigned i = 0; i < proto_nargs; ++i) {
5822      QualType argTy = proto->getArgType(i);
5823
5824      // Look at the promotion type of enum types, since that is the type used
5825      // to pass enum values.
5826      if (const EnumType *Enum = argTy->getAs<EnumType>())
5827        argTy = Enum->getDecl()->getPromotionType();
5828
5829      if (argTy->isPromotableIntegerType() ||
5830          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
5831        return QualType();
5832    }
5833
5834    if (allLTypes) return lhs;
5835    if (allRTypes) return rhs;
5836
5837    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
5838    EPI.ExtInfo = einfo;
5839    return getFunctionType(retType, proto->arg_type_begin(),
5840                           proto->getNumArgs(), EPI);
5841  }
5842
5843  if (allLTypes) return lhs;
5844  if (allRTypes) return rhs;
5845  return getFunctionNoProtoType(retType, einfo);
5846}
5847
5848QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
5849                                bool OfBlockPointer,
5850                                bool Unqualified, bool BlockReturnType) {
5851  // C++ [expr]: If an expression initially has the type "reference to T", the
5852  // type is adjusted to "T" prior to any further analysis, the expression
5853  // designates the object or function denoted by the reference, and the
5854  // expression is an lvalue unless the reference is an rvalue reference and
5855  // the expression is a function call (possibly inside parentheses).
5856  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
5857  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
5858
5859  if (Unqualified) {
5860    LHS = LHS.getUnqualifiedType();
5861    RHS = RHS.getUnqualifiedType();
5862  }
5863
5864  QualType LHSCan = getCanonicalType(LHS),
5865           RHSCan = getCanonicalType(RHS);
5866
5867  // If two types are identical, they are compatible.
5868  if (LHSCan == RHSCan)
5869    return LHS;
5870
5871  // If the qualifiers are different, the types aren't compatible... mostly.
5872  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5873  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5874  if (LQuals != RQuals) {
5875    // If any of these qualifiers are different, we have a type
5876    // mismatch.
5877    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5878        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
5879        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
5880      return QualType();
5881
5882    // Exactly one GC qualifier difference is allowed: __strong is
5883    // okay if the other type has no GC qualifier but is an Objective
5884    // C object pointer (i.e. implicitly strong by default).  We fix
5885    // this by pretending that the unqualified type was actually
5886    // qualified __strong.
5887    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5888    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5889    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5890
5891    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5892      return QualType();
5893
5894    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
5895      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
5896    }
5897    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
5898      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
5899    }
5900    return QualType();
5901  }
5902
5903  // Okay, qualifiers are equal.
5904
5905  Type::TypeClass LHSClass = LHSCan->getTypeClass();
5906  Type::TypeClass RHSClass = RHSCan->getTypeClass();
5907
5908  // We want to consider the two function types to be the same for these
5909  // comparisons, just force one to the other.
5910  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
5911  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
5912
5913  // Same as above for arrays
5914  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
5915    LHSClass = Type::ConstantArray;
5916  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
5917    RHSClass = Type::ConstantArray;
5918
5919  // ObjCInterfaces are just specialized ObjCObjects.
5920  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
5921  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
5922
5923  // Canonicalize ExtVector -> Vector.
5924  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
5925  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
5926
5927  // If the canonical type classes don't match.
5928  if (LHSClass != RHSClass) {
5929    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
5930    // a signed integer type, or an unsigned integer type.
5931    // Compatibility is based on the underlying type, not the promotion
5932    // type.
5933    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
5934      QualType TINT = ETy->getDecl()->getIntegerType();
5935      if (!TINT.isNull() && hasSameType(TINT, RHSCan.getUnqualifiedType()))
5936        return RHS;
5937    }
5938    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
5939      QualType TINT = ETy->getDecl()->getIntegerType();
5940      if (!TINT.isNull() && hasSameType(TINT, LHSCan.getUnqualifiedType()))
5941        return LHS;
5942    }
5943    // allow block pointer type to match an 'id' type.
5944    if (OfBlockPointer && !BlockReturnType) {
5945       if (LHS->isObjCIdType() && RHS->isBlockPointerType())
5946         return LHS;
5947      if (RHS->isObjCIdType() && LHS->isBlockPointerType())
5948        return RHS;
5949    }
5950
5951    return QualType();
5952  }
5953
5954  // The canonical type classes match.
5955  switch (LHSClass) {
5956#define TYPE(Class, Base)
5957#define ABSTRACT_TYPE(Class, Base)
5958#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
5959#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
5960#define DEPENDENT_TYPE(Class, Base) case Type::Class:
5961#include "clang/AST/TypeNodes.def"
5962    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
5963
5964  case Type::LValueReference:
5965  case Type::RValueReference:
5966  case Type::MemberPointer:
5967    llvm_unreachable("C++ should never be in mergeTypes");
5968
5969  case Type::ObjCInterface:
5970  case Type::IncompleteArray:
5971  case Type::VariableArray:
5972  case Type::FunctionProto:
5973  case Type::ExtVector:
5974    llvm_unreachable("Types are eliminated above");
5975
5976  case Type::Pointer:
5977  {
5978    // Merge two pointer types, while trying to preserve typedef info
5979    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
5980    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
5981    if (Unqualified) {
5982      LHSPointee = LHSPointee.getUnqualifiedType();
5983      RHSPointee = RHSPointee.getUnqualifiedType();
5984    }
5985    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
5986                                     Unqualified);
5987    if (ResultType.isNull()) return QualType();
5988    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5989      return LHS;
5990    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5991      return RHS;
5992    return getPointerType(ResultType);
5993  }
5994  case Type::BlockPointer:
5995  {
5996    // Merge two block pointer types, while trying to preserve typedef info
5997    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
5998    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
5999    if (Unqualified) {
6000      LHSPointee = LHSPointee.getUnqualifiedType();
6001      RHSPointee = RHSPointee.getUnqualifiedType();
6002    }
6003    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
6004                                     Unqualified);
6005    if (ResultType.isNull()) return QualType();
6006    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
6007      return LHS;
6008    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
6009      return RHS;
6010    return getBlockPointerType(ResultType);
6011  }
6012  case Type::Atomic:
6013  {
6014    // Merge two pointer types, while trying to preserve typedef info
6015    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
6016    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
6017    if (Unqualified) {
6018      LHSValue = LHSValue.getUnqualifiedType();
6019      RHSValue = RHSValue.getUnqualifiedType();
6020    }
6021    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
6022                                     Unqualified);
6023    if (ResultType.isNull()) return QualType();
6024    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
6025      return LHS;
6026    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
6027      return RHS;
6028    return getAtomicType(ResultType);
6029  }
6030  case Type::ConstantArray:
6031  {
6032    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
6033    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
6034    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
6035      return QualType();
6036
6037    QualType LHSElem = getAsArrayType(LHS)->getElementType();
6038    QualType RHSElem = getAsArrayType(RHS)->getElementType();
6039    if (Unqualified) {
6040      LHSElem = LHSElem.getUnqualifiedType();
6041      RHSElem = RHSElem.getUnqualifiedType();
6042    }
6043
6044    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
6045    if (ResultType.isNull()) return QualType();
6046    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
6047      return LHS;
6048    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
6049      return RHS;
6050    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
6051                                          ArrayType::ArraySizeModifier(), 0);
6052    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
6053                                          ArrayType::ArraySizeModifier(), 0);
6054    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
6055    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
6056    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
6057      return LHS;
6058    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
6059      return RHS;
6060    if (LVAT) {
6061      // FIXME: This isn't correct! But tricky to implement because
6062      // the array's size has to be the size of LHS, but the type
6063      // has to be different.
6064      return LHS;
6065    }
6066    if (RVAT) {
6067      // FIXME: This isn't correct! But tricky to implement because
6068      // the array's size has to be the size of RHS, but the type
6069      // has to be different.
6070      return RHS;
6071    }
6072    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
6073    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
6074    return getIncompleteArrayType(ResultType,
6075                                  ArrayType::ArraySizeModifier(), 0);
6076  }
6077  case Type::FunctionNoProto:
6078    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
6079  case Type::Record:
6080  case Type::Enum:
6081    return QualType();
6082  case Type::Builtin:
6083    // Only exactly equal builtin types are compatible, which is tested above.
6084    return QualType();
6085  case Type::Complex:
6086    // Distinct complex types are incompatible.
6087    return QualType();
6088  case Type::Vector:
6089    // FIXME: The merged type should be an ExtVector!
6090    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
6091                             RHSCan->getAs<VectorType>()))
6092      return LHS;
6093    return QualType();
6094  case Type::ObjCObject: {
6095    // Check if the types are assignment compatible.
6096    // FIXME: This should be type compatibility, e.g. whether
6097    // "LHS x; RHS x;" at global scope is legal.
6098    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
6099    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
6100    if (canAssignObjCInterfaces(LHSIface, RHSIface))
6101      return LHS;
6102
6103    return QualType();
6104  }
6105  case Type::ObjCObjectPointer: {
6106    if (OfBlockPointer) {
6107      if (canAssignObjCInterfacesInBlockPointer(
6108                                          LHS->getAs<ObjCObjectPointerType>(),
6109                                          RHS->getAs<ObjCObjectPointerType>(),
6110                                          BlockReturnType))
6111        return LHS;
6112      return QualType();
6113    }
6114    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
6115                                RHS->getAs<ObjCObjectPointerType>()))
6116      return LHS;
6117
6118    return QualType();
6119  }
6120  }
6121
6122  llvm_unreachable("Invalid Type::Class!");
6123}
6124
6125bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
6126                   const FunctionProtoType *FromFunctionType,
6127                   const FunctionProtoType *ToFunctionType) {
6128  if (FromFunctionType->hasAnyConsumedArgs() !=
6129      ToFunctionType->hasAnyConsumedArgs())
6130    return false;
6131  FunctionProtoType::ExtProtoInfo FromEPI =
6132    FromFunctionType->getExtProtoInfo();
6133  FunctionProtoType::ExtProtoInfo ToEPI =
6134    ToFunctionType->getExtProtoInfo();
6135  if (FromEPI.ConsumedArguments && ToEPI.ConsumedArguments)
6136    for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs();
6137         ArgIdx != NumArgs; ++ArgIdx)  {
6138      if (FromEPI.ConsumedArguments[ArgIdx] !=
6139          ToEPI.ConsumedArguments[ArgIdx])
6140        return false;
6141    }
6142  return true;
6143}
6144
6145/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
6146/// 'RHS' attributes and returns the merged version; including for function
6147/// return types.
6148QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
6149  QualType LHSCan = getCanonicalType(LHS),
6150  RHSCan = getCanonicalType(RHS);
6151  // If two types are identical, they are compatible.
6152  if (LHSCan == RHSCan)
6153    return LHS;
6154  if (RHSCan->isFunctionType()) {
6155    if (!LHSCan->isFunctionType())
6156      return QualType();
6157    QualType OldReturnType =
6158      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
6159    QualType NewReturnType =
6160      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
6161    QualType ResReturnType =
6162      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
6163    if (ResReturnType.isNull())
6164      return QualType();
6165    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
6166      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
6167      // In either case, use OldReturnType to build the new function type.
6168      const FunctionType *F = LHS->getAs<FunctionType>();
6169      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
6170        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
6171        EPI.ExtInfo = getFunctionExtInfo(LHS);
6172        QualType ResultType
6173          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
6174                            FPT->getNumArgs(), EPI);
6175        return ResultType;
6176      }
6177    }
6178    return QualType();
6179  }
6180
6181  // If the qualifiers are different, the types can still be merged.
6182  Qualifiers LQuals = LHSCan.getLocalQualifiers();
6183  Qualifiers RQuals = RHSCan.getLocalQualifiers();
6184  if (LQuals != RQuals) {
6185    // If any of these qualifiers are different, we have a type mismatch.
6186    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
6187        LQuals.getAddressSpace() != RQuals.getAddressSpace())
6188      return QualType();
6189
6190    // Exactly one GC qualifier difference is allowed: __strong is
6191    // okay if the other type has no GC qualifier but is an Objective
6192    // C object pointer (i.e. implicitly strong by default).  We fix
6193    // this by pretending that the unqualified type was actually
6194    // qualified __strong.
6195    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
6196    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
6197    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
6198
6199    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
6200      return QualType();
6201
6202    if (GC_L == Qualifiers::Strong)
6203      return LHS;
6204    if (GC_R == Qualifiers::Strong)
6205      return RHS;
6206    return QualType();
6207  }
6208
6209  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
6210    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6211    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6212    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
6213    if (ResQT == LHSBaseQT)
6214      return LHS;
6215    if (ResQT == RHSBaseQT)
6216      return RHS;
6217  }
6218  return QualType();
6219}
6220
6221//===----------------------------------------------------------------------===//
6222//                         Integer Predicates
6223//===----------------------------------------------------------------------===//
6224
6225unsigned ASTContext::getIntWidth(QualType T) const {
6226  if (const EnumType *ET = dyn_cast<EnumType>(T))
6227    T = ET->getDecl()->getIntegerType();
6228  if (T->isBooleanType())
6229    return 1;
6230  // For builtin types, just use the standard type sizing method
6231  return (unsigned)getTypeSize(T);
6232}
6233
6234QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
6235  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
6236
6237  // Turn <4 x signed int> -> <4 x unsigned int>
6238  if (const VectorType *VTy = T->getAs<VectorType>())
6239    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
6240                         VTy->getNumElements(), VTy->getVectorKind());
6241
6242  // For enums, we return the unsigned version of the base type.
6243  if (const EnumType *ETy = T->getAs<EnumType>())
6244    T = ETy->getDecl()->getIntegerType();
6245
6246  const BuiltinType *BTy = T->getAs<BuiltinType>();
6247  assert(BTy && "Unexpected signed integer type");
6248  switch (BTy->getKind()) {
6249  case BuiltinType::Char_S:
6250  case BuiltinType::SChar:
6251    return UnsignedCharTy;
6252  case BuiltinType::Short:
6253    return UnsignedShortTy;
6254  case BuiltinType::Int:
6255    return UnsignedIntTy;
6256  case BuiltinType::Long:
6257    return UnsignedLongTy;
6258  case BuiltinType::LongLong:
6259    return UnsignedLongLongTy;
6260  case BuiltinType::Int128:
6261    return UnsignedInt128Ty;
6262  default:
6263    llvm_unreachable("Unexpected signed integer type");
6264  }
6265}
6266
6267ASTMutationListener::~ASTMutationListener() { }
6268
6269
6270//===----------------------------------------------------------------------===//
6271//                          Builtin Type Computation
6272//===----------------------------------------------------------------------===//
6273
6274/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
6275/// pointer over the consumed characters.  This returns the resultant type.  If
6276/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
6277/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
6278/// a vector of "i*".
6279///
6280/// RequiresICE is filled in on return to indicate whether the value is required
6281/// to be an Integer Constant Expression.
6282static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
6283                                  ASTContext::GetBuiltinTypeError &Error,
6284                                  bool &RequiresICE,
6285                                  bool AllowTypeModifiers) {
6286  // Modifiers.
6287  int HowLong = 0;
6288  bool Signed = false, Unsigned = false;
6289  RequiresICE = false;
6290
6291  // Read the prefixed modifiers first.
6292  bool Done = false;
6293  while (!Done) {
6294    switch (*Str++) {
6295    default: Done = true; --Str; break;
6296    case 'I':
6297      RequiresICE = true;
6298      break;
6299    case 'S':
6300      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
6301      assert(!Signed && "Can't use 'S' modifier multiple times!");
6302      Signed = true;
6303      break;
6304    case 'U':
6305      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
6306      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
6307      Unsigned = true;
6308      break;
6309    case 'L':
6310      assert(HowLong <= 2 && "Can't have LLLL modifier");
6311      ++HowLong;
6312      break;
6313    }
6314  }
6315
6316  QualType Type;
6317
6318  // Read the base type.
6319  switch (*Str++) {
6320  default: llvm_unreachable("Unknown builtin type letter!");
6321  case 'v':
6322    assert(HowLong == 0 && !Signed && !Unsigned &&
6323           "Bad modifiers used with 'v'!");
6324    Type = Context.VoidTy;
6325    break;
6326  case 'f':
6327    assert(HowLong == 0 && !Signed && !Unsigned &&
6328           "Bad modifiers used with 'f'!");
6329    Type = Context.FloatTy;
6330    break;
6331  case 'd':
6332    assert(HowLong < 2 && !Signed && !Unsigned &&
6333           "Bad modifiers used with 'd'!");
6334    if (HowLong)
6335      Type = Context.LongDoubleTy;
6336    else
6337      Type = Context.DoubleTy;
6338    break;
6339  case 's':
6340    assert(HowLong == 0 && "Bad modifiers used with 's'!");
6341    if (Unsigned)
6342      Type = Context.UnsignedShortTy;
6343    else
6344      Type = Context.ShortTy;
6345    break;
6346  case 'i':
6347    if (HowLong == 3)
6348      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
6349    else if (HowLong == 2)
6350      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
6351    else if (HowLong == 1)
6352      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
6353    else
6354      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
6355    break;
6356  case 'c':
6357    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
6358    if (Signed)
6359      Type = Context.SignedCharTy;
6360    else if (Unsigned)
6361      Type = Context.UnsignedCharTy;
6362    else
6363      Type = Context.CharTy;
6364    break;
6365  case 'b': // boolean
6366    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
6367    Type = Context.BoolTy;
6368    break;
6369  case 'z':  // size_t.
6370    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
6371    Type = Context.getSizeType();
6372    break;
6373  case 'F':
6374    Type = Context.getCFConstantStringType();
6375    break;
6376  case 'G':
6377    Type = Context.getObjCIdType();
6378    break;
6379  case 'H':
6380    Type = Context.getObjCSelType();
6381    break;
6382  case 'a':
6383    Type = Context.getBuiltinVaListType();
6384    assert(!Type.isNull() && "builtin va list type not initialized!");
6385    break;
6386  case 'A':
6387    // This is a "reference" to a va_list; however, what exactly
6388    // this means depends on how va_list is defined. There are two
6389    // different kinds of va_list: ones passed by value, and ones
6390    // passed by reference.  An example of a by-value va_list is
6391    // x86, where va_list is a char*. An example of by-ref va_list
6392    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
6393    // we want this argument to be a char*&; for x86-64, we want
6394    // it to be a __va_list_tag*.
6395    Type = Context.getBuiltinVaListType();
6396    assert(!Type.isNull() && "builtin va list type not initialized!");
6397    if (Type->isArrayType())
6398      Type = Context.getArrayDecayedType(Type);
6399    else
6400      Type = Context.getLValueReferenceType(Type);
6401    break;
6402  case 'V': {
6403    char *End;
6404    unsigned NumElements = strtoul(Str, &End, 10);
6405    assert(End != Str && "Missing vector size");
6406    Str = End;
6407
6408    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
6409                                             RequiresICE, false);
6410    assert(!RequiresICE && "Can't require vector ICE");
6411
6412    // TODO: No way to make AltiVec vectors in builtins yet.
6413    Type = Context.getVectorType(ElementType, NumElements,
6414                                 VectorType::GenericVector);
6415    break;
6416  }
6417  case 'X': {
6418    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
6419                                             false);
6420    assert(!RequiresICE && "Can't require complex ICE");
6421    Type = Context.getComplexType(ElementType);
6422    break;
6423  }
6424  case 'Y' : {
6425    Type = Context.getPointerDiffType();
6426    break;
6427  }
6428  case 'P':
6429    Type = Context.getFILEType();
6430    if (Type.isNull()) {
6431      Error = ASTContext::GE_Missing_stdio;
6432      return QualType();
6433    }
6434    break;
6435  case 'J':
6436    if (Signed)
6437      Type = Context.getsigjmp_bufType();
6438    else
6439      Type = Context.getjmp_bufType();
6440
6441    if (Type.isNull()) {
6442      Error = ASTContext::GE_Missing_setjmp;
6443      return QualType();
6444    }
6445    break;
6446  case 'K':
6447    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'K'!");
6448    Type = Context.getucontext_tType();
6449
6450    if (Type.isNull()) {
6451      Error = ASTContext::GE_Missing_ucontext;
6452      return QualType();
6453    }
6454    break;
6455  }
6456
6457  // If there are modifiers and if we're allowed to parse them, go for it.
6458  Done = !AllowTypeModifiers;
6459  while (!Done) {
6460    switch (char c = *Str++) {
6461    default: Done = true; --Str; break;
6462    case '*':
6463    case '&': {
6464      // Both pointers and references can have their pointee types
6465      // qualified with an address space.
6466      char *End;
6467      unsigned AddrSpace = strtoul(Str, &End, 10);
6468      if (End != Str && AddrSpace != 0) {
6469        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
6470        Str = End;
6471      }
6472      if (c == '*')
6473        Type = Context.getPointerType(Type);
6474      else
6475        Type = Context.getLValueReferenceType(Type);
6476      break;
6477    }
6478    // FIXME: There's no way to have a built-in with an rvalue ref arg.
6479    case 'C':
6480      Type = Type.withConst();
6481      break;
6482    case 'D':
6483      Type = Context.getVolatileType(Type);
6484      break;
6485    case 'R':
6486      Type = Type.withRestrict();
6487      break;
6488    }
6489  }
6490
6491  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
6492         "Integer constant 'I' type must be an integer");
6493
6494  return Type;
6495}
6496
6497/// GetBuiltinType - Return the type for the specified builtin.
6498QualType ASTContext::GetBuiltinType(unsigned Id,
6499                                    GetBuiltinTypeError &Error,
6500                                    unsigned *IntegerConstantArgs) const {
6501  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
6502
6503  SmallVector<QualType, 8> ArgTypes;
6504
6505  bool RequiresICE = false;
6506  Error = GE_None;
6507  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
6508                                       RequiresICE, true);
6509  if (Error != GE_None)
6510    return QualType();
6511
6512  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
6513
6514  while (TypeStr[0] && TypeStr[0] != '.') {
6515    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
6516    if (Error != GE_None)
6517      return QualType();
6518
6519    // If this argument is required to be an IntegerConstantExpression and the
6520    // caller cares, fill in the bitmask we return.
6521    if (RequiresICE && IntegerConstantArgs)
6522      *IntegerConstantArgs |= 1 << ArgTypes.size();
6523
6524    // Do array -> pointer decay.  The builtin should use the decayed type.
6525    if (Ty->isArrayType())
6526      Ty = getArrayDecayedType(Ty);
6527
6528    ArgTypes.push_back(Ty);
6529  }
6530
6531  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
6532         "'.' should only occur at end of builtin type list!");
6533
6534  FunctionType::ExtInfo EI;
6535  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
6536
6537  bool Variadic = (TypeStr[0] == '.');
6538
6539  // We really shouldn't be making a no-proto type here, especially in C++.
6540  if (ArgTypes.empty() && Variadic)
6541    return getFunctionNoProtoType(ResType, EI);
6542
6543  FunctionProtoType::ExtProtoInfo EPI;
6544  EPI.ExtInfo = EI;
6545  EPI.Variadic = Variadic;
6546
6547  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(), EPI);
6548}
6549
6550GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
6551  GVALinkage External = GVA_StrongExternal;
6552
6553  Linkage L = FD->getLinkage();
6554  switch (L) {
6555  case NoLinkage:
6556  case InternalLinkage:
6557  case UniqueExternalLinkage:
6558    return GVA_Internal;
6559
6560  case ExternalLinkage:
6561    switch (FD->getTemplateSpecializationKind()) {
6562    case TSK_Undeclared:
6563    case TSK_ExplicitSpecialization:
6564      External = GVA_StrongExternal;
6565      break;
6566
6567    case TSK_ExplicitInstantiationDefinition:
6568      return GVA_ExplicitTemplateInstantiation;
6569
6570    case TSK_ExplicitInstantiationDeclaration:
6571    case TSK_ImplicitInstantiation:
6572      External = GVA_TemplateInstantiation;
6573      break;
6574    }
6575  }
6576
6577  if (!FD->isInlined())
6578    return External;
6579
6580  if (!getLangOpts().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
6581    // GNU or C99 inline semantics. Determine whether this symbol should be
6582    // externally visible.
6583    if (FD->isInlineDefinitionExternallyVisible())
6584      return External;
6585
6586    // C99 inline semantics, where the symbol is not externally visible.
6587    return GVA_C99Inline;
6588  }
6589
6590  // C++0x [temp.explicit]p9:
6591  //   [ Note: The intent is that an inline function that is the subject of
6592  //   an explicit instantiation declaration will still be implicitly
6593  //   instantiated when used so that the body can be considered for
6594  //   inlining, but that no out-of-line copy of the inline function would be
6595  //   generated in the translation unit. -- end note ]
6596  if (FD->getTemplateSpecializationKind()
6597                                       == TSK_ExplicitInstantiationDeclaration)
6598    return GVA_C99Inline;
6599
6600  return GVA_CXXInline;
6601}
6602
6603GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
6604  // If this is a static data member, compute the kind of template
6605  // specialization. Otherwise, this variable is not part of a
6606  // template.
6607  TemplateSpecializationKind TSK = TSK_Undeclared;
6608  if (VD->isStaticDataMember())
6609    TSK = VD->getTemplateSpecializationKind();
6610
6611  Linkage L = VD->getLinkage();
6612  if (L == ExternalLinkage && getLangOpts().CPlusPlus &&
6613      VD->getType()->getLinkage() == UniqueExternalLinkage)
6614    L = UniqueExternalLinkage;
6615
6616  switch (L) {
6617  case NoLinkage:
6618  case InternalLinkage:
6619  case UniqueExternalLinkage:
6620    return GVA_Internal;
6621
6622  case ExternalLinkage:
6623    switch (TSK) {
6624    case TSK_Undeclared:
6625    case TSK_ExplicitSpecialization:
6626      return GVA_StrongExternal;
6627
6628    case TSK_ExplicitInstantiationDeclaration:
6629      llvm_unreachable("Variable should not be instantiated");
6630      // Fall through to treat this like any other instantiation.
6631
6632    case TSK_ExplicitInstantiationDefinition:
6633      return GVA_ExplicitTemplateInstantiation;
6634
6635    case TSK_ImplicitInstantiation:
6636      return GVA_TemplateInstantiation;
6637    }
6638  }
6639
6640  llvm_unreachable("Invalid Linkage!");
6641}
6642
6643bool ASTContext::DeclMustBeEmitted(const Decl *D) {
6644  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
6645    if (!VD->isFileVarDecl())
6646      return false;
6647  } else if (!isa<FunctionDecl>(D))
6648    return false;
6649
6650  // Weak references don't produce any output by themselves.
6651  if (D->hasAttr<WeakRefAttr>())
6652    return false;
6653
6654  // Aliases and used decls are required.
6655  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
6656    return true;
6657
6658  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
6659    // Forward declarations aren't required.
6660    if (!FD->doesThisDeclarationHaveABody())
6661      return FD->doesDeclarationForceExternallyVisibleDefinition();
6662
6663    // Constructors and destructors are required.
6664    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
6665      return true;
6666
6667    // The key function for a class is required.
6668    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
6669      const CXXRecordDecl *RD = MD->getParent();
6670      if (MD->isOutOfLine() && RD->isDynamicClass()) {
6671        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
6672        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
6673          return true;
6674      }
6675    }
6676
6677    GVALinkage Linkage = GetGVALinkageForFunction(FD);
6678
6679    // static, static inline, always_inline, and extern inline functions can
6680    // always be deferred.  Normal inline functions can be deferred in C99/C++.
6681    // Implicit template instantiations can also be deferred in C++.
6682    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
6683        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
6684      return false;
6685    return true;
6686  }
6687
6688  const VarDecl *VD = cast<VarDecl>(D);
6689  assert(VD->isFileVarDecl() && "Expected file scoped var");
6690
6691  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
6692    return false;
6693
6694  // Structs that have non-trivial constructors or destructors are required.
6695
6696  // FIXME: Handle references.
6697  // FIXME: Be more selective about which constructors we care about.
6698  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
6699    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
6700      if (RD->hasDefinition() && !(RD->hasTrivialDefaultConstructor() &&
6701                                   RD->hasTrivialCopyConstructor() &&
6702                                   RD->hasTrivialMoveConstructor() &&
6703                                   RD->hasTrivialDestructor()))
6704        return true;
6705    }
6706  }
6707
6708  GVALinkage L = GetGVALinkageForVariable(VD);
6709  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
6710    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
6711      return false;
6712  }
6713
6714  return true;
6715}
6716
6717CallingConv ASTContext::getDefaultMethodCallConv() {
6718  // Pass through to the C++ ABI object
6719  return ABI->getDefaultMethodCallConv();
6720}
6721
6722bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
6723  // Pass through to the C++ ABI object
6724  return ABI->isNearlyEmpty(RD);
6725}
6726
6727MangleContext *ASTContext::createMangleContext() {
6728  switch (Target->getCXXABI()) {
6729  case CXXABI_ARM:
6730  case CXXABI_Itanium:
6731    return createItaniumMangleContext(*this, getDiagnostics());
6732  case CXXABI_Microsoft:
6733    return createMicrosoftMangleContext(*this, getDiagnostics());
6734  }
6735  llvm_unreachable("Unsupported ABI");
6736}
6737
6738CXXABI::~CXXABI() {}
6739
6740size_t ASTContext::getSideTableAllocatedMemory() const {
6741  return ASTRecordLayouts.getMemorySize()
6742    + llvm::capacity_in_bytes(ObjCLayouts)
6743    + llvm::capacity_in_bytes(KeyFunctions)
6744    + llvm::capacity_in_bytes(ObjCImpls)
6745    + llvm::capacity_in_bytes(BlockVarCopyInits)
6746    + llvm::capacity_in_bytes(DeclAttrs)
6747    + llvm::capacity_in_bytes(InstantiatedFromStaticDataMember)
6748    + llvm::capacity_in_bytes(InstantiatedFromUsingDecl)
6749    + llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl)
6750    + llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl)
6751    + llvm::capacity_in_bytes(OverriddenMethods)
6752    + llvm::capacity_in_bytes(Types)
6753    + llvm::capacity_in_bytes(VariableArrayTypes)
6754    + llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
6755}
6756
6757unsigned ASTContext::getLambdaManglingNumber(CXXMethodDecl *CallOperator) {
6758  CXXRecordDecl *Lambda = CallOperator->getParent();
6759  return LambdaMangleContexts[Lambda->getDeclContext()]
6760           .getManglingNumber(CallOperator);
6761}
6762
6763
6764void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
6765  ParamIndices[D] = index;
6766}
6767
6768unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
6769  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
6770  assert(I != ParamIndices.end() &&
6771         "ParmIndices lacks entry set by ParmVarDecl");
6772  return I->second;
6773}
6774