ASTContext.cpp revision 855243789cb44799c03f4c7216d3d6308805f549 
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, getCanonicalType(Arg.getIntegralType()));
3340
3341    case TemplateArgument::Type:
3342      return TemplateArgument(getCanonicalType(Arg.getAsType()));
3343
3344    case TemplateArgument::Pack: {
3345      if (Arg.pack_size() == 0)
3346        return Arg;
3347
3348      TemplateArgument *CanonArgs
3349        = new (*this) TemplateArgument[Arg.pack_size()];
3350      unsigned Idx = 0;
3351      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
3352                                        AEnd = Arg.pack_end();
3353           A != AEnd; (void)++A, ++Idx)
3354        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
3355
3356      return TemplateArgument(CanonArgs, Arg.pack_size());
3357    }
3358  }
3359
3360  // Silence GCC warning
3361  llvm_unreachable("Unhandled template argument kind");
3362}
3363
3364NestedNameSpecifier *
3365ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
3366  if (!NNS)
3367    return 0;
3368
3369  switch (NNS->getKind()) {
3370  case NestedNameSpecifier::Identifier:
3371    // Canonicalize the prefix but keep the identifier the same.
3372    return NestedNameSpecifier::Create(*this,
3373                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
3374                                       NNS->getAsIdentifier());
3375
3376  case NestedNameSpecifier::Namespace:
3377    // A namespace is canonical; build a nested-name-specifier with
3378    // this namespace and no prefix.
3379    return NestedNameSpecifier::Create(*this, 0,
3380                                 NNS->getAsNamespace()->getOriginalNamespace());
3381
3382  case NestedNameSpecifier::NamespaceAlias:
3383    // A namespace is canonical; build a nested-name-specifier with
3384    // this namespace and no prefix.
3385    return NestedNameSpecifier::Create(*this, 0,
3386                                    NNS->getAsNamespaceAlias()->getNamespace()
3387                                                      ->getOriginalNamespace());
3388
3389  case NestedNameSpecifier::TypeSpec:
3390  case NestedNameSpecifier::TypeSpecWithTemplate: {
3391    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
3392
3393    // If we have some kind of dependent-named type (e.g., "typename T::type"),
3394    // break it apart into its prefix and identifier, then reconsititute those
3395    // as the canonical nested-name-specifier. This is required to canonicalize
3396    // a dependent nested-name-specifier involving typedefs of dependent-name
3397    // types, e.g.,
3398    //   typedef typename T::type T1;
3399    //   typedef typename T1::type T2;
3400    if (const DependentNameType *DNT = T->getAs<DependentNameType>())
3401      return NestedNameSpecifier::Create(*this, DNT->getQualifier(),
3402                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
3403
3404    // Otherwise, just canonicalize the type, and force it to be a TypeSpec.
3405    // FIXME: Why are TypeSpec and TypeSpecWithTemplate distinct in the
3406    // first place?
3407    return NestedNameSpecifier::Create(*this, 0, false,
3408                                       const_cast<Type*>(T.getTypePtr()));
3409  }
3410
3411  case NestedNameSpecifier::Global:
3412    // The global specifier is canonical and unique.
3413    return NNS;
3414  }
3415
3416  llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
3417}
3418
3419
3420const ArrayType *ASTContext::getAsArrayType(QualType T) const {
3421  // Handle the non-qualified case efficiently.
3422  if (!T.hasLocalQualifiers()) {
3423    // Handle the common positive case fast.
3424    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
3425      return AT;
3426  }
3427
3428  // Handle the common negative case fast.
3429  if (!isa<ArrayType>(T.getCanonicalType()))
3430    return 0;
3431
3432  // Apply any qualifiers from the array type to the element type.  This
3433  // implements C99 6.7.3p8: "If the specification of an array type includes
3434  // any type qualifiers, the element type is so qualified, not the array type."
3435
3436  // If we get here, we either have type qualifiers on the type, or we have
3437  // sugar such as a typedef in the way.  If we have type qualifiers on the type
3438  // we must propagate them down into the element type.
3439
3440  SplitQualType split = T.getSplitDesugaredType();
3441  Qualifiers qs = split.Quals;
3442
3443  // If we have a simple case, just return now.
3444  const ArrayType *ATy = dyn_cast<ArrayType>(split.Ty);
3445  if (ATy == 0 || qs.empty())
3446    return ATy;
3447
3448  // Otherwise, we have an array and we have qualifiers on it.  Push the
3449  // qualifiers into the array element type and return a new array type.
3450  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
3451
3452  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
3453    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
3454                                                CAT->getSizeModifier(),
3455                                           CAT->getIndexTypeCVRQualifiers()));
3456  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
3457    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
3458                                                  IAT->getSizeModifier(),
3459                                           IAT->getIndexTypeCVRQualifiers()));
3460
3461  if (const DependentSizedArrayType *DSAT
3462        = dyn_cast<DependentSizedArrayType>(ATy))
3463    return cast<ArrayType>(
3464                     getDependentSizedArrayType(NewEltTy,
3465                                                DSAT->getSizeExpr(),
3466                                                DSAT->getSizeModifier(),
3467                                              DSAT->getIndexTypeCVRQualifiers(),
3468                                                DSAT->getBracketsRange()));
3469
3470  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
3471  return cast<ArrayType>(getVariableArrayType(NewEltTy,
3472                                              VAT->getSizeExpr(),
3473                                              VAT->getSizeModifier(),
3474                                              VAT->getIndexTypeCVRQualifiers(),
3475                                              VAT->getBracketsRange()));
3476}
3477
3478QualType ASTContext::getAdjustedParameterType(QualType T) const {
3479  // C99 6.7.5.3p7:
3480  //   A declaration of a parameter as "array of type" shall be
3481  //   adjusted to "qualified pointer to type", where the type
3482  //   qualifiers (if any) are those specified within the [ and ] of
3483  //   the array type derivation.
3484  if (T->isArrayType())
3485    return getArrayDecayedType(T);
3486
3487  // C99 6.7.5.3p8:
3488  //   A declaration of a parameter as "function returning type"
3489  //   shall be adjusted to "pointer to function returning type", as
3490  //   in 6.3.2.1.
3491  if (T->isFunctionType())
3492    return getPointerType(T);
3493
3494  return T;
3495}
3496
3497QualType ASTContext::getSignatureParameterType(QualType T) const {
3498  T = getVariableArrayDecayedType(T);
3499  T = getAdjustedParameterType(T);
3500  return T.getUnqualifiedType();
3501}
3502
3503/// getArrayDecayedType - Return the properly qualified result of decaying the
3504/// specified array type to a pointer.  This operation is non-trivial when
3505/// handling typedefs etc.  The canonical type of "T" must be an array type,
3506/// this returns a pointer to a properly qualified element of the array.
3507///
3508/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
3509QualType ASTContext::getArrayDecayedType(QualType Ty) const {
3510  // Get the element type with 'getAsArrayType' so that we don't lose any
3511  // typedefs in the element type of the array.  This also handles propagation
3512  // of type qualifiers from the array type into the element type if present
3513  // (C99 6.7.3p8).
3514  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
3515  assert(PrettyArrayType && "Not an array type!");
3516
3517  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
3518
3519  // int x[restrict 4] ->  int *restrict
3520  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
3521}
3522
3523QualType ASTContext::getBaseElementType(const ArrayType *array) const {
3524  return getBaseElementType(array->getElementType());
3525}
3526
3527QualType ASTContext::getBaseElementType(QualType type) const {
3528  Qualifiers qs;
3529  while (true) {
3530    SplitQualType split = type.getSplitDesugaredType();
3531    const ArrayType *array = split.Ty->getAsArrayTypeUnsafe();
3532    if (!array) break;
3533
3534    type = array->getElementType();
3535    qs.addConsistentQualifiers(split.Quals);
3536  }
3537
3538  return getQualifiedType(type, qs);
3539}
3540
3541/// getConstantArrayElementCount - Returns number of constant array elements.
3542uint64_t
3543ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
3544  uint64_t ElementCount = 1;
3545  do {
3546    ElementCount *= CA->getSize().getZExtValue();
3547    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
3548  } while (CA);
3549  return ElementCount;
3550}
3551
3552/// getFloatingRank - Return a relative rank for floating point types.
3553/// This routine will assert if passed a built-in type that isn't a float.
3554static FloatingRank getFloatingRank(QualType T) {
3555  if (const ComplexType *CT = T->getAs<ComplexType>())
3556    return getFloatingRank(CT->getElementType());
3557
3558  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
3559  switch (T->getAs<BuiltinType>()->getKind()) {
3560  default: llvm_unreachable("getFloatingRank(): not a floating type");
3561  case BuiltinType::Half:       return HalfRank;
3562  case BuiltinType::Float:      return FloatRank;
3563  case BuiltinType::Double:     return DoubleRank;
3564  case BuiltinType::LongDouble: return LongDoubleRank;
3565  }
3566}
3567
3568/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
3569/// point or a complex type (based on typeDomain/typeSize).
3570/// 'typeDomain' is a real floating point or complex type.
3571/// 'typeSize' is a real floating point or complex type.
3572QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
3573                                                       QualType Domain) const {
3574  FloatingRank EltRank = getFloatingRank(Size);
3575  if (Domain->isComplexType()) {
3576    switch (EltRank) {
3577    case HalfRank: llvm_unreachable("Complex half is not supported");
3578    case FloatRank:      return FloatComplexTy;
3579    case DoubleRank:     return DoubleComplexTy;
3580    case LongDoubleRank: return LongDoubleComplexTy;
3581    }
3582  }
3583
3584  assert(Domain->isRealFloatingType() && "Unknown domain!");
3585  switch (EltRank) {
3586  case HalfRank: llvm_unreachable("Half ranks are not valid here");
3587  case FloatRank:      return FloatTy;
3588  case DoubleRank:     return DoubleTy;
3589  case LongDoubleRank: return LongDoubleTy;
3590  }
3591  llvm_unreachable("getFloatingRank(): illegal value for rank");
3592}
3593
3594/// getFloatingTypeOrder - Compare the rank of the two specified floating
3595/// point types, ignoring the domain of the type (i.e. 'double' ==
3596/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3597/// LHS < RHS, return -1.
3598int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
3599  FloatingRank LHSR = getFloatingRank(LHS);
3600  FloatingRank RHSR = getFloatingRank(RHS);
3601
3602  if (LHSR == RHSR)
3603    return 0;
3604  if (LHSR > RHSR)
3605    return 1;
3606  return -1;
3607}
3608
3609/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
3610/// routine will assert if passed a built-in type that isn't an integer or enum,
3611/// or if it is not canonicalized.
3612unsigned ASTContext::getIntegerRank(const Type *T) const {
3613  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
3614
3615  switch (cast<BuiltinType>(T)->getKind()) {
3616  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
3617  case BuiltinType::Bool:
3618    return 1 + (getIntWidth(BoolTy) << 3);
3619  case BuiltinType::Char_S:
3620  case BuiltinType::Char_U:
3621  case BuiltinType::SChar:
3622  case BuiltinType::UChar:
3623    return 2 + (getIntWidth(CharTy) << 3);
3624  case BuiltinType::Short:
3625  case BuiltinType::UShort:
3626    return 3 + (getIntWidth(ShortTy) << 3);
3627  case BuiltinType::Int:
3628  case BuiltinType::UInt:
3629    return 4 + (getIntWidth(IntTy) << 3);
3630  case BuiltinType::Long:
3631  case BuiltinType::ULong:
3632    return 5 + (getIntWidth(LongTy) << 3);
3633  case BuiltinType::LongLong:
3634  case BuiltinType::ULongLong:
3635    return 6 + (getIntWidth(LongLongTy) << 3);
3636  case BuiltinType::Int128:
3637  case BuiltinType::UInt128:
3638    return 7 + (getIntWidth(Int128Ty) << 3);
3639  }
3640}
3641
3642/// \brief Whether this is a promotable bitfield reference according
3643/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
3644///
3645/// \returns the type this bit-field will promote to, or NULL if no
3646/// promotion occurs.
3647QualType ASTContext::isPromotableBitField(Expr *E) const {
3648  if (E->isTypeDependent() || E->isValueDependent())
3649    return QualType();
3650
3651  FieldDecl *Field = E->getBitField();
3652  if (!Field)
3653    return QualType();
3654
3655  QualType FT = Field->getType();
3656
3657  uint64_t BitWidth = Field->getBitWidthValue(*this);
3658  uint64_t IntSize = getTypeSize(IntTy);
3659  // GCC extension compatibility: if the bit-field size is less than or equal
3660  // to the size of int, it gets promoted no matter what its type is.
3661  // For instance, unsigned long bf : 4 gets promoted to signed int.
3662  if (BitWidth < IntSize)
3663    return IntTy;
3664
3665  if (BitWidth == IntSize)
3666    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
3667
3668  // Types bigger than int are not subject to promotions, and therefore act
3669  // like the base type.
3670  // FIXME: This doesn't quite match what gcc does, but what gcc does here
3671  // is ridiculous.
3672  return QualType();
3673}
3674
3675/// getPromotedIntegerType - Returns the type that Promotable will
3676/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
3677/// integer type.
3678QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
3679  assert(!Promotable.isNull());
3680  assert(Promotable->isPromotableIntegerType());
3681  if (const EnumType *ET = Promotable->getAs<EnumType>())
3682    return ET->getDecl()->getPromotionType();
3683
3684  if (const BuiltinType *BT = Promotable->getAs<BuiltinType>()) {
3685    // C++ [conv.prom]: A prvalue of type char16_t, char32_t, or wchar_t
3686    // (3.9.1) can be converted to a prvalue of the first of the following
3687    // types that can represent all the values of its underlying type:
3688    // int, unsigned int, long int, unsigned long int, long long int, or
3689    // unsigned long long int [...]
3690    // FIXME: Is there some better way to compute this?
3691    if (BT->getKind() == BuiltinType::WChar_S ||
3692        BT->getKind() == BuiltinType::WChar_U ||
3693        BT->getKind() == BuiltinType::Char16 ||
3694        BT->getKind() == BuiltinType::Char32) {
3695      bool FromIsSigned = BT->getKind() == BuiltinType::WChar_S;
3696      uint64_t FromSize = getTypeSize(BT);
3697      QualType PromoteTypes[] = { IntTy, UnsignedIntTy, LongTy, UnsignedLongTy,
3698                                  LongLongTy, UnsignedLongLongTy };
3699      for (size_t Idx = 0; Idx < llvm::array_lengthof(PromoteTypes); ++Idx) {
3700        uint64_t ToSize = getTypeSize(PromoteTypes[Idx]);
3701        if (FromSize < ToSize ||
3702            (FromSize == ToSize &&
3703             FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType()))
3704          return PromoteTypes[Idx];
3705      }
3706      llvm_unreachable("char type should fit into long long");
3707    }
3708  }
3709
3710  // At this point, we should have a signed or unsigned integer type.
3711  if (Promotable->isSignedIntegerType())
3712    return IntTy;
3713  uint64_t PromotableSize = getTypeSize(Promotable);
3714  uint64_t IntSize = getTypeSize(IntTy);
3715  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3716  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3717}
3718
3719/// \brief Recurses in pointer/array types until it finds an objc retainable
3720/// type and returns its ownership.
3721Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
3722  while (!T.isNull()) {
3723    if (T.getObjCLifetime() != Qualifiers::OCL_None)
3724      return T.getObjCLifetime();
3725    if (T->isArrayType())
3726      T = getBaseElementType(T);
3727    else if (const PointerType *PT = T->getAs<PointerType>())
3728      T = PT->getPointeeType();
3729    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3730      T = RT->getPointeeType();
3731    else
3732      break;
3733  }
3734
3735  return Qualifiers::OCL_None;
3736}
3737
3738/// getIntegerTypeOrder - Returns the highest ranked integer type:
3739/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3740/// LHS < RHS, return -1.
3741int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
3742  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
3743  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
3744  if (LHSC == RHSC) return 0;
3745
3746  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3747  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3748
3749  unsigned LHSRank = getIntegerRank(LHSC);
3750  unsigned RHSRank = getIntegerRank(RHSC);
3751
3752  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3753    if (LHSRank == RHSRank) return 0;
3754    return LHSRank > RHSRank ? 1 : -1;
3755  }
3756
3757  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3758  if (LHSUnsigned) {
3759    // If the unsigned [LHS] type is larger, return it.
3760    if (LHSRank >= RHSRank)
3761      return 1;
3762
3763    // If the signed type can represent all values of the unsigned type, it
3764    // wins.  Because we are dealing with 2's complement and types that are
3765    // powers of two larger than each other, this is always safe.
3766    return -1;
3767  }
3768
3769  // If the unsigned [RHS] type is larger, return it.
3770  if (RHSRank >= LHSRank)
3771    return -1;
3772
3773  // If the signed type can represent all values of the unsigned type, it
3774  // wins.  Because we are dealing with 2's complement and types that are
3775  // powers of two larger than each other, this is always safe.
3776  return 1;
3777}
3778
3779static RecordDecl *
3780CreateRecordDecl(const ASTContext &Ctx, RecordDecl::TagKind TK,
3781                 DeclContext *DC, IdentifierInfo *Id) {
3782  SourceLocation Loc;
3783  if (Ctx.getLangOpts().CPlusPlus)
3784    return CXXRecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3785  else
3786    return RecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3787}
3788
3789// getCFConstantStringType - Return the type used for constant CFStrings.
3790QualType ASTContext::getCFConstantStringType() const {
3791  if (!CFConstantStringTypeDecl) {
3792    CFConstantStringTypeDecl =
3793      CreateRecordDecl(*this, TTK_Struct, TUDecl,
3794                       &Idents.get("NSConstantString"));
3795    CFConstantStringTypeDecl->startDefinition();
3796
3797    QualType FieldTypes[4];
3798
3799    // const int *isa;
3800    FieldTypes[0] = getPointerType(IntTy.withConst());
3801    // int flags;
3802    FieldTypes[1] = IntTy;
3803    // const char *str;
3804    FieldTypes[2] = getPointerType(CharTy.withConst());
3805    // long length;
3806    FieldTypes[3] = LongTy;
3807
3808    // Create fields
3809    for (unsigned i = 0; i < 4; ++i) {
3810      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3811                                           SourceLocation(),
3812                                           SourceLocation(), 0,
3813                                           FieldTypes[i], /*TInfo=*/0,
3814                                           /*BitWidth=*/0,
3815                                           /*Mutable=*/false,
3816                                           /*HasInit=*/false);
3817      Field->setAccess(AS_public);
3818      CFConstantStringTypeDecl->addDecl(Field);
3819    }
3820
3821    CFConstantStringTypeDecl->completeDefinition();
3822  }
3823
3824  return getTagDeclType(CFConstantStringTypeDecl);
3825}
3826
3827void ASTContext::setCFConstantStringType(QualType T) {
3828  const RecordType *Rec = T->getAs<RecordType>();
3829  assert(Rec && "Invalid CFConstantStringType");
3830  CFConstantStringTypeDecl = Rec->getDecl();
3831}
3832
3833QualType ASTContext::getBlockDescriptorType() const {
3834  if (BlockDescriptorType)
3835    return getTagDeclType(BlockDescriptorType);
3836
3837  RecordDecl *T;
3838  // FIXME: Needs the FlagAppleBlock bit.
3839  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3840                       &Idents.get("__block_descriptor"));
3841  T->startDefinition();
3842
3843  QualType FieldTypes[] = {
3844    UnsignedLongTy,
3845    UnsignedLongTy,
3846  };
3847
3848  const char *FieldNames[] = {
3849    "reserved",
3850    "Size"
3851  };
3852
3853  for (size_t i = 0; i < 2; ++i) {
3854    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3855                                         SourceLocation(),
3856                                         &Idents.get(FieldNames[i]),
3857                                         FieldTypes[i], /*TInfo=*/0,
3858                                         /*BitWidth=*/0,
3859                                         /*Mutable=*/false,
3860                                         /*HasInit=*/false);
3861    Field->setAccess(AS_public);
3862    T->addDecl(Field);
3863  }
3864
3865  T->completeDefinition();
3866
3867  BlockDescriptorType = T;
3868
3869  return getTagDeclType(BlockDescriptorType);
3870}
3871
3872QualType ASTContext::getBlockDescriptorExtendedType() const {
3873  if (BlockDescriptorExtendedType)
3874    return getTagDeclType(BlockDescriptorExtendedType);
3875
3876  RecordDecl *T;
3877  // FIXME: Needs the FlagAppleBlock bit.
3878  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3879                       &Idents.get("__block_descriptor_withcopydispose"));
3880  T->startDefinition();
3881
3882  QualType FieldTypes[] = {
3883    UnsignedLongTy,
3884    UnsignedLongTy,
3885    getPointerType(VoidPtrTy),
3886    getPointerType(VoidPtrTy)
3887  };
3888
3889  const char *FieldNames[] = {
3890    "reserved",
3891    "Size",
3892    "CopyFuncPtr",
3893    "DestroyFuncPtr"
3894  };
3895
3896  for (size_t i = 0; i < 4; ++i) {
3897    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3898                                         SourceLocation(),
3899                                         &Idents.get(FieldNames[i]),
3900                                         FieldTypes[i], /*TInfo=*/0,
3901                                         /*BitWidth=*/0,
3902                                         /*Mutable=*/false,
3903                                         /*HasInit=*/false);
3904    Field->setAccess(AS_public);
3905    T->addDecl(Field);
3906  }
3907
3908  T->completeDefinition();
3909
3910  BlockDescriptorExtendedType = T;
3911
3912  return getTagDeclType(BlockDescriptorExtendedType);
3913}
3914
3915bool ASTContext::BlockRequiresCopying(QualType Ty) const {
3916  if (Ty->isObjCRetainableType())
3917    return true;
3918  if (getLangOpts().CPlusPlus) {
3919    if (const RecordType *RT = Ty->getAs<RecordType>()) {
3920      CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
3921      return RD->hasConstCopyConstructor();
3922
3923    }
3924  }
3925  return false;
3926}
3927
3928QualType
3929ASTContext::BuildByRefType(StringRef DeclName, QualType Ty) const {
3930  //  type = struct __Block_byref_1_X {
3931  //    void *__isa;
3932  //    struct __Block_byref_1_X *__forwarding;
3933  //    unsigned int __flags;
3934  //    unsigned int __size;
3935  //    void *__copy_helper;            // as needed
3936  //    void *__destroy_help            // as needed
3937  //    int X;
3938  //  } *
3939
3940  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3941
3942  // FIXME: Move up
3943  SmallString<36> Name;
3944  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3945                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3946  RecordDecl *T;
3947  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, &Idents.get(Name.str()));
3948  T->startDefinition();
3949  QualType Int32Ty = IntTy;
3950  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3951  QualType FieldTypes[] = {
3952    getPointerType(VoidPtrTy),
3953    getPointerType(getTagDeclType(T)),
3954    Int32Ty,
3955    Int32Ty,
3956    getPointerType(VoidPtrTy),
3957    getPointerType(VoidPtrTy),
3958    Ty
3959  };
3960
3961  StringRef FieldNames[] = {
3962    "__isa",
3963    "__forwarding",
3964    "__flags",
3965    "__size",
3966    "__copy_helper",
3967    "__destroy_helper",
3968    DeclName,
3969  };
3970
3971  for (size_t i = 0; i < 7; ++i) {
3972    if (!HasCopyAndDispose && i >=4 && i <= 5)
3973      continue;
3974    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3975                                         SourceLocation(),
3976                                         &Idents.get(FieldNames[i]),
3977                                         FieldTypes[i], /*TInfo=*/0,
3978                                         /*BitWidth=*/0, /*Mutable=*/false,
3979                                         /*HasInit=*/false);
3980    Field->setAccess(AS_public);
3981    T->addDecl(Field);
3982  }
3983
3984  T->completeDefinition();
3985
3986  return getPointerType(getTagDeclType(T));
3987}
3988
3989TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
3990  if (!ObjCInstanceTypeDecl)
3991    ObjCInstanceTypeDecl = TypedefDecl::Create(*this,
3992                                               getTranslationUnitDecl(),
3993                                               SourceLocation(),
3994                                               SourceLocation(),
3995                                               &Idents.get("instancetype"),
3996                                     getTrivialTypeSourceInfo(getObjCIdType()));
3997  return ObjCInstanceTypeDecl;
3998}
3999
4000// This returns true if a type has been typedefed to BOOL:
4001// typedef <type> BOOL;
4002static bool isTypeTypedefedAsBOOL(QualType T) {
4003  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
4004    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
4005      return II->isStr("BOOL");
4006
4007  return false;
4008}
4009
4010/// getObjCEncodingTypeSize returns size of type for objective-c encoding
4011/// purpose.
4012CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
4013  if (!type->isIncompleteArrayType() && type->isIncompleteType())
4014    return CharUnits::Zero();
4015
4016  CharUnits sz = getTypeSizeInChars(type);
4017
4018  // Make all integer and enum types at least as large as an int
4019  if (sz.isPositive() && type->isIntegralOrEnumerationType())
4020    sz = std::max(sz, getTypeSizeInChars(IntTy));
4021  // Treat arrays as pointers, since that's how they're passed in.
4022  else if (type->isArrayType())
4023    sz = getTypeSizeInChars(VoidPtrTy);
4024  return sz;
4025}
4026
4027static inline
4028std::string charUnitsToString(const CharUnits &CU) {
4029  return llvm::itostr(CU.getQuantity());
4030}
4031
4032/// getObjCEncodingForBlock - Return the encoded type for this block
4033/// declaration.
4034std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
4035  std::string S;
4036
4037  const BlockDecl *Decl = Expr->getBlockDecl();
4038  QualType BlockTy =
4039      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
4040  // Encode result type.
4041  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
4042  // Compute size of all parameters.
4043  // Start with computing size of a pointer in number of bytes.
4044  // FIXME: There might(should) be a better way of doing this computation!
4045  SourceLocation Loc;
4046  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4047  CharUnits ParmOffset = PtrSize;
4048  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
4049       E = Decl->param_end(); PI != E; ++PI) {
4050    QualType PType = (*PI)->getType();
4051    CharUnits sz = getObjCEncodingTypeSize(PType);
4052    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
4053    ParmOffset += sz;
4054  }
4055  // Size of the argument frame
4056  S += charUnitsToString(ParmOffset);
4057  // Block pointer and offset.
4058  S += "@?0";
4059
4060  // Argument types.
4061  ParmOffset = PtrSize;
4062  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
4063       Decl->param_end(); PI != E; ++PI) {
4064    ParmVarDecl *PVDecl = *PI;
4065    QualType PType = PVDecl->getOriginalType();
4066    if (const ArrayType *AT =
4067          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4068      // Use array's original type only if it has known number of
4069      // elements.
4070      if (!isa<ConstantArrayType>(AT))
4071        PType = PVDecl->getType();
4072    } else if (PType->isFunctionType())
4073      PType = PVDecl->getType();
4074    getObjCEncodingForType(PType, S);
4075    S += charUnitsToString(ParmOffset);
4076    ParmOffset += getObjCEncodingTypeSize(PType);
4077  }
4078
4079  return S;
4080}
4081
4082bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
4083                                                std::string& S) {
4084  // Encode result type.
4085  getObjCEncodingForType(Decl->getResultType(), S);
4086  CharUnits ParmOffset;
4087  // Compute size of all parameters.
4088  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4089       E = Decl->param_end(); PI != E; ++PI) {
4090    QualType PType = (*PI)->getType();
4091    CharUnits sz = getObjCEncodingTypeSize(PType);
4092    if (sz.isZero())
4093      return true;
4094
4095    assert (sz.isPositive() &&
4096        "getObjCEncodingForFunctionDecl - Incomplete param type");
4097    ParmOffset += sz;
4098  }
4099  S += charUnitsToString(ParmOffset);
4100  ParmOffset = CharUnits::Zero();
4101
4102  // Argument types.
4103  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4104       E = Decl->param_end(); PI != E; ++PI) {
4105    ParmVarDecl *PVDecl = *PI;
4106    QualType PType = PVDecl->getOriginalType();
4107    if (const ArrayType *AT =
4108          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4109      // Use array's original type only if it has known number of
4110      // elements.
4111      if (!isa<ConstantArrayType>(AT))
4112        PType = PVDecl->getType();
4113    } else if (PType->isFunctionType())
4114      PType = PVDecl->getType();
4115    getObjCEncodingForType(PType, S);
4116    S += charUnitsToString(ParmOffset);
4117    ParmOffset += getObjCEncodingTypeSize(PType);
4118  }
4119
4120  return false;
4121}
4122
4123/// getObjCEncodingForMethodParameter - Return the encoded type for a single
4124/// method parameter or return type. If Extended, include class names and
4125/// block object types.
4126void ASTContext::getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
4127                                                   QualType T, std::string& S,
4128                                                   bool Extended) const {
4129  // Encode type qualifer, 'in', 'inout', etc. for the parameter.
4130  getObjCEncodingForTypeQualifier(QT, S);
4131  // Encode parameter type.
4132  getObjCEncodingForTypeImpl(T, S, true, true, 0,
4133                             true     /*OutermostType*/,
4134                             false    /*EncodingProperty*/,
4135                             false    /*StructField*/,
4136                             Extended /*EncodeBlockParameters*/,
4137                             Extended /*EncodeClassNames*/);
4138}
4139
4140/// getObjCEncodingForMethodDecl - Return the encoded type for this method
4141/// declaration.
4142bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
4143                                              std::string& S,
4144                                              bool Extended) const {
4145  // FIXME: This is not very efficient.
4146  // Encode return type.
4147  getObjCEncodingForMethodParameter(Decl->getObjCDeclQualifier(),
4148                                    Decl->getResultType(), S, Extended);
4149  // Compute size of all parameters.
4150  // Start with computing size of a pointer in number of bytes.
4151  // FIXME: There might(should) be a better way of doing this computation!
4152  SourceLocation Loc;
4153  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4154  // The first two arguments (self and _cmd) are pointers; account for
4155  // their size.
4156  CharUnits ParmOffset = 2 * PtrSize;
4157  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4158       E = Decl->sel_param_end(); PI != E; ++PI) {
4159    QualType PType = (*PI)->getType();
4160    CharUnits sz = getObjCEncodingTypeSize(PType);
4161    if (sz.isZero())
4162      return true;
4163
4164    assert (sz.isPositive() &&
4165        "getObjCEncodingForMethodDecl - Incomplete param type");
4166    ParmOffset += sz;
4167  }
4168  S += charUnitsToString(ParmOffset);
4169  S += "@0:";
4170  S += charUnitsToString(PtrSize);
4171
4172  // Argument types.
4173  ParmOffset = 2 * PtrSize;
4174  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4175       E = Decl->sel_param_end(); PI != E; ++PI) {
4176    const ParmVarDecl *PVDecl = *PI;
4177    QualType PType = PVDecl->getOriginalType();
4178    if (const ArrayType *AT =
4179          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4180      // Use array's original type only if it has known number of
4181      // elements.
4182      if (!isa<ConstantArrayType>(AT))
4183        PType = PVDecl->getType();
4184    } else if (PType->isFunctionType())
4185      PType = PVDecl->getType();
4186    getObjCEncodingForMethodParameter(PVDecl->getObjCDeclQualifier(),
4187                                      PType, S, Extended);
4188    S += charUnitsToString(ParmOffset);
4189    ParmOffset += getObjCEncodingTypeSize(PType);
4190  }
4191
4192  return false;
4193}
4194
4195/// getObjCEncodingForPropertyDecl - Return the encoded type for this
4196/// property declaration. If non-NULL, Container must be either an
4197/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
4198/// NULL when getting encodings for protocol properties.
4199/// Property attributes are stored as a comma-delimited C string. The simple
4200/// attributes readonly and bycopy are encoded as single characters. The
4201/// parametrized attributes, getter=name, setter=name, and ivar=name, are
4202/// encoded as single characters, followed by an identifier. Property types
4203/// are also encoded as a parametrized attribute. The characters used to encode
4204/// these attributes are defined by the following enumeration:
4205/// @code
4206/// enum PropertyAttributes {
4207/// kPropertyReadOnly = 'R',   // property is read-only.
4208/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
4209/// kPropertyByref = '&',  // property is a reference to the value last assigned
4210/// kPropertyDynamic = 'D',    // property is dynamic
4211/// kPropertyGetter = 'G',     // followed by getter selector name
4212/// kPropertySetter = 'S',     // followed by setter selector name
4213/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
4214/// kPropertyType = 'T'              // followed by old-style type encoding.
4215/// kPropertyWeak = 'W'              // 'weak' property
4216/// kPropertyStrong = 'P'            // property GC'able
4217/// kPropertyNonAtomic = 'N'         // property non-atomic
4218/// };
4219/// @endcode
4220void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
4221                                                const Decl *Container,
4222                                                std::string& S) const {
4223  // Collect information from the property implementation decl(s).
4224  bool Dynamic = false;
4225  ObjCPropertyImplDecl *SynthesizePID = 0;
4226
4227  // FIXME: Duplicated code due to poor abstraction.
4228  if (Container) {
4229    if (const ObjCCategoryImplDecl *CID =
4230        dyn_cast<ObjCCategoryImplDecl>(Container)) {
4231      for (ObjCCategoryImplDecl::propimpl_iterator
4232             i = CID->propimpl_begin(), e = CID->propimpl_end();
4233           i != e; ++i) {
4234        ObjCPropertyImplDecl *PID = *i;
4235        if (PID->getPropertyDecl() == PD) {
4236          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4237            Dynamic = true;
4238          } else {
4239            SynthesizePID = PID;
4240          }
4241        }
4242      }
4243    } else {
4244      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
4245      for (ObjCCategoryImplDecl::propimpl_iterator
4246             i = OID->propimpl_begin(), e = OID->propimpl_end();
4247           i != e; ++i) {
4248        ObjCPropertyImplDecl *PID = *i;
4249        if (PID->getPropertyDecl() == PD) {
4250          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4251            Dynamic = true;
4252          } else {
4253            SynthesizePID = PID;
4254          }
4255        }
4256      }
4257    }
4258  }
4259
4260  // FIXME: This is not very efficient.
4261  S = "T";
4262
4263  // Encode result type.
4264  // GCC has some special rules regarding encoding of properties which
4265  // closely resembles encoding of ivars.
4266  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
4267                             true /* outermost type */,
4268                             true /* encoding for property */);
4269
4270  if (PD->isReadOnly()) {
4271    S += ",R";
4272  } else {
4273    switch (PD->getSetterKind()) {
4274    case ObjCPropertyDecl::Assign: break;
4275    case ObjCPropertyDecl::Copy:   S += ",C"; break;
4276    case ObjCPropertyDecl::Retain: S += ",&"; break;
4277    case ObjCPropertyDecl::Weak:   S += ",W"; break;
4278    }
4279  }
4280
4281  // It really isn't clear at all what this means, since properties
4282  // are "dynamic by default".
4283  if (Dynamic)
4284    S += ",D";
4285
4286  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
4287    S += ",N";
4288
4289  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
4290    S += ",G";
4291    S += PD->getGetterName().getAsString();
4292  }
4293
4294  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
4295    S += ",S";
4296    S += PD->getSetterName().getAsString();
4297  }
4298
4299  if (SynthesizePID) {
4300    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
4301    S += ",V";
4302    S += OID->getNameAsString();
4303  }
4304
4305  // FIXME: OBJCGC: weak & strong
4306}
4307
4308/// getLegacyIntegralTypeEncoding -
4309/// Another legacy compatibility encoding: 32-bit longs are encoded as
4310/// 'l' or 'L' , but not always.  For typedefs, we need to use
4311/// 'i' or 'I' instead if encoding a struct field, or a pointer!
4312///
4313void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
4314  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
4315    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
4316      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
4317        PointeeTy = UnsignedIntTy;
4318      else
4319        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
4320          PointeeTy = IntTy;
4321    }
4322  }
4323}
4324
4325void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
4326                                        const FieldDecl *Field) const {
4327  // We follow the behavior of gcc, expanding structures which are
4328  // directly pointed to, and expanding embedded structures. Note that
4329  // these rules are sufficient to prevent recursive encoding of the
4330  // same type.
4331  getObjCEncodingForTypeImpl(T, S, true, true, Field,
4332                             true /* outermost type */);
4333}
4334
4335static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
4336    switch (T->getAs<BuiltinType>()->getKind()) {
4337    default: llvm_unreachable("Unhandled builtin type kind");
4338    case BuiltinType::Void:       return 'v';
4339    case BuiltinType::Bool:       return 'B';
4340    case BuiltinType::Char_U:
4341    case BuiltinType::UChar:      return 'C';
4342    case BuiltinType::UShort:     return 'S';
4343    case BuiltinType::UInt:       return 'I';
4344    case BuiltinType::ULong:
4345        return C->getIntWidth(T) == 32 ? 'L' : 'Q';
4346    case BuiltinType::UInt128:    return 'T';
4347    case BuiltinType::ULongLong:  return 'Q';
4348    case BuiltinType::Char_S:
4349    case BuiltinType::SChar:      return 'c';
4350    case BuiltinType::Short:      return 's';
4351    case BuiltinType::WChar_S:
4352    case BuiltinType::WChar_U:
4353    case BuiltinType::Int:        return 'i';
4354    case BuiltinType::Long:
4355      return C->getIntWidth(T) == 32 ? 'l' : 'q';
4356    case BuiltinType::LongLong:   return 'q';
4357    case BuiltinType::Int128:     return 't';
4358    case BuiltinType::Float:      return 'f';
4359    case BuiltinType::Double:     return 'd';
4360    case BuiltinType::LongDouble: return 'D';
4361    }
4362}
4363
4364static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
4365  EnumDecl *Enum = ET->getDecl();
4366
4367  // The encoding of an non-fixed enum type is always 'i', regardless of size.
4368  if (!Enum->isFixed())
4369    return 'i';
4370
4371  // The encoding of a fixed enum type matches its fixed underlying type.
4372  return ObjCEncodingForPrimitiveKind(C, Enum->getIntegerType());
4373}
4374
4375static void EncodeBitField(const ASTContext *Ctx, std::string& S,
4376                           QualType T, const FieldDecl *FD) {
4377  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
4378  S += 'b';
4379  // The NeXT runtime encodes bit fields as b followed by the number of bits.
4380  // The GNU runtime requires more information; bitfields are encoded as b,
4381  // then the offset (in bits) of the first element, then the type of the
4382  // bitfield, then the size in bits.  For example, in this structure:
4383  //
4384  // struct
4385  // {
4386  //    int integer;
4387  //    int flags:2;
4388  // };
4389  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
4390  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
4391  // information is not especially sensible, but we're stuck with it for
4392  // compatibility with GCC, although providing it breaks anything that
4393  // actually uses runtime introspection and wants to work on both runtimes...
4394  if (!Ctx->getLangOpts().NeXTRuntime) {
4395    const RecordDecl *RD = FD->getParent();
4396    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
4397    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
4398    if (const EnumType *ET = T->getAs<EnumType>())
4399      S += ObjCEncodingForEnumType(Ctx, ET);
4400    else
4401      S += ObjCEncodingForPrimitiveKind(Ctx, T);
4402  }
4403  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
4404}
4405
4406// FIXME: Use SmallString for accumulating string.
4407void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
4408                                            bool ExpandPointedToStructures,
4409                                            bool ExpandStructures,
4410                                            const FieldDecl *FD,
4411                                            bool OutermostType,
4412                                            bool EncodingProperty,
4413                                            bool StructField,
4414                                            bool EncodeBlockParameters,
4415                                            bool EncodeClassNames) const {
4416  if (T->getAs<BuiltinType>()) {
4417    if (FD && FD->isBitField())
4418      return EncodeBitField(this, S, T, FD);
4419    S += ObjCEncodingForPrimitiveKind(this, T);
4420    return;
4421  }
4422
4423  if (const ComplexType *CT = T->getAs<ComplexType>()) {
4424    S += 'j';
4425    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
4426                               false);
4427    return;
4428  }
4429
4430  // encoding for pointer or r3eference types.
4431  QualType PointeeTy;
4432  if (const PointerType *PT = T->getAs<PointerType>()) {
4433    if (PT->isObjCSelType()) {
4434      S += ':';
4435      return;
4436    }
4437    PointeeTy = PT->getPointeeType();
4438  }
4439  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4440    PointeeTy = RT->getPointeeType();
4441  if (!PointeeTy.isNull()) {
4442    bool isReadOnly = false;
4443    // For historical/compatibility reasons, the read-only qualifier of the
4444    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
4445    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
4446    // Also, do not emit the 'r' for anything but the outermost type!
4447    if (isa<TypedefType>(T.getTypePtr())) {
4448      if (OutermostType && T.isConstQualified()) {
4449        isReadOnly = true;
4450        S += 'r';
4451      }
4452    } else if (OutermostType) {
4453      QualType P = PointeeTy;
4454      while (P->getAs<PointerType>())
4455        P = P->getAs<PointerType>()->getPointeeType();
4456      if (P.isConstQualified()) {
4457        isReadOnly = true;
4458        S += 'r';
4459      }
4460    }
4461    if (isReadOnly) {
4462      // Another legacy compatibility encoding. Some ObjC qualifier and type
4463      // combinations need to be rearranged.
4464      // Rewrite "in const" from "nr" to "rn"
4465      if (StringRef(S).endswith("nr"))
4466        S.replace(S.end()-2, S.end(), "rn");
4467    }
4468
4469    if (PointeeTy->isCharType()) {
4470      // char pointer types should be encoded as '*' unless it is a
4471      // type that has been typedef'd to 'BOOL'.
4472      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
4473        S += '*';
4474        return;
4475      }
4476    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
4477      // GCC binary compat: Need to convert "struct objc_class *" to "#".
4478      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
4479        S += '#';
4480        return;
4481      }
4482      // GCC binary compat: Need to convert "struct objc_object *" to "@".
4483      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
4484        S += '@';
4485        return;
4486      }
4487      // fall through...
4488    }
4489    S += '^';
4490    getLegacyIntegralTypeEncoding(PointeeTy);
4491
4492    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
4493                               NULL);
4494    return;
4495  }
4496
4497  if (const ArrayType *AT =
4498      // Ignore type qualifiers etc.
4499        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
4500    if (isa<IncompleteArrayType>(AT) && !StructField) {
4501      // Incomplete arrays are encoded as a pointer to the array element.
4502      S += '^';
4503
4504      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4505                                 false, ExpandStructures, FD);
4506    } else {
4507      S += '[';
4508
4509      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
4510        if (getTypeSize(CAT->getElementType()) == 0)
4511          S += '0';
4512        else
4513          S += llvm::utostr(CAT->getSize().getZExtValue());
4514      } else {
4515        //Variable length arrays are encoded as a regular array with 0 elements.
4516        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
4517               "Unknown array type!");
4518        S += '0';
4519      }
4520
4521      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4522                                 false, ExpandStructures, FD);
4523      S += ']';
4524    }
4525    return;
4526  }
4527
4528  if (T->getAs<FunctionType>()) {
4529    S += '?';
4530    return;
4531  }
4532
4533  if (const RecordType *RTy = T->getAs<RecordType>()) {
4534    RecordDecl *RDecl = RTy->getDecl();
4535    S += RDecl->isUnion() ? '(' : '{';
4536    // Anonymous structures print as '?'
4537    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
4538      S += II->getName();
4539      if (ClassTemplateSpecializationDecl *Spec
4540          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
4541        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
4542        std::string TemplateArgsStr
4543          = TemplateSpecializationType::PrintTemplateArgumentList(
4544                                            TemplateArgs.data(),
4545                                            TemplateArgs.size(),
4546                                            (*this).getPrintingPolicy());
4547
4548        S += TemplateArgsStr;
4549      }
4550    } else {
4551      S += '?';
4552    }
4553    if (ExpandStructures) {
4554      S += '=';
4555      if (!RDecl->isUnion()) {
4556        getObjCEncodingForStructureImpl(RDecl, S, FD);
4557      } else {
4558        for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4559                                     FieldEnd = RDecl->field_end();
4560             Field != FieldEnd; ++Field) {
4561          if (FD) {
4562            S += '"';
4563            S += Field->getNameAsString();
4564            S += '"';
4565          }
4566
4567          // Special case bit-fields.
4568          if (Field->isBitField()) {
4569            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
4570                                       *Field);
4571          } else {
4572            QualType qt = Field->getType();
4573            getLegacyIntegralTypeEncoding(qt);
4574            getObjCEncodingForTypeImpl(qt, S, false, true,
4575                                       FD, /*OutermostType*/false,
4576                                       /*EncodingProperty*/false,
4577                                       /*StructField*/true);
4578          }
4579        }
4580      }
4581    }
4582    S += RDecl->isUnion() ? ')' : '}';
4583    return;
4584  }
4585
4586  if (const EnumType *ET = T->getAs<EnumType>()) {
4587    if (FD && FD->isBitField())
4588      EncodeBitField(this, S, T, FD);
4589    else
4590      S += ObjCEncodingForEnumType(this, ET);
4591    return;
4592  }
4593
4594  if (const BlockPointerType *BT = T->getAs<BlockPointerType>()) {
4595    S += "@?"; // Unlike a pointer-to-function, which is "^?".
4596    if (EncodeBlockParameters) {
4597      const FunctionType *FT = BT->getPointeeType()->getAs<FunctionType>();
4598
4599      S += '<';
4600      // Block return type
4601      getObjCEncodingForTypeImpl(FT->getResultType(), S,
4602                                 ExpandPointedToStructures, ExpandStructures,
4603                                 FD,
4604                                 false /* OutermostType */,
4605                                 EncodingProperty,
4606                                 false /* StructField */,
4607                                 EncodeBlockParameters,
4608                                 EncodeClassNames);
4609      // Block self
4610      S += "@?";
4611      // Block parameters
4612      if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT)) {
4613        for (FunctionProtoType::arg_type_iterator I = FPT->arg_type_begin(),
4614               E = FPT->arg_type_end(); I && (I != E); ++I) {
4615          getObjCEncodingForTypeImpl(*I, S,
4616                                     ExpandPointedToStructures,
4617                                     ExpandStructures,
4618                                     FD,
4619                                     false /* OutermostType */,
4620                                     EncodingProperty,
4621                                     false /* StructField */,
4622                                     EncodeBlockParameters,
4623                                     EncodeClassNames);
4624        }
4625      }
4626      S += '>';
4627    }
4628    return;
4629  }
4630
4631  // Ignore protocol qualifiers when mangling at this level.
4632  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
4633    T = OT->getBaseType();
4634
4635  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
4636    // @encode(class_name)
4637    ObjCInterfaceDecl *OI = OIT->getDecl();
4638    S += '{';
4639    const IdentifierInfo *II = OI->getIdentifier();
4640    S += II->getName();
4641    S += '=';
4642    SmallVector<const ObjCIvarDecl*, 32> Ivars;
4643    DeepCollectObjCIvars(OI, true, Ivars);
4644    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
4645      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
4646      if (Field->isBitField())
4647        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
4648      else
4649        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
4650    }
4651    S += '}';
4652    return;
4653  }
4654
4655  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
4656    if (OPT->isObjCIdType()) {
4657      S += '@';
4658      return;
4659    }
4660
4661    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
4662      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
4663      // Since this is a binary compatibility issue, need to consult with runtime
4664      // folks. Fortunately, this is a *very* obsure construct.
4665      S += '#';
4666      return;
4667    }
4668
4669    if (OPT->isObjCQualifiedIdType()) {
4670      getObjCEncodingForTypeImpl(getObjCIdType(), S,
4671                                 ExpandPointedToStructures,
4672                                 ExpandStructures, FD);
4673      if (FD || EncodingProperty || EncodeClassNames) {
4674        // Note that we do extended encoding of protocol qualifer list
4675        // Only when doing ivar or property encoding.
4676        S += '"';
4677        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4678             E = OPT->qual_end(); I != E; ++I) {
4679          S += '<';
4680          S += (*I)->getNameAsString();
4681          S += '>';
4682        }
4683        S += '"';
4684      }
4685      return;
4686    }
4687
4688    QualType PointeeTy = OPT->getPointeeType();
4689    if (!EncodingProperty &&
4690        isa<TypedefType>(PointeeTy.getTypePtr())) {
4691      // Another historical/compatibility reason.
4692      // We encode the underlying type which comes out as
4693      // {...};
4694      S += '^';
4695      getObjCEncodingForTypeImpl(PointeeTy, S,
4696                                 false, ExpandPointedToStructures,
4697                                 NULL);
4698      return;
4699    }
4700
4701    S += '@';
4702    if (OPT->getInterfaceDecl() &&
4703        (FD || EncodingProperty || EncodeClassNames)) {
4704      S += '"';
4705      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4706      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4707           E = OPT->qual_end(); I != E; ++I) {
4708        S += '<';
4709        S += (*I)->getNameAsString();
4710        S += '>';
4711      }
4712      S += '"';
4713    }
4714    return;
4715  }
4716
4717  // gcc just blithely ignores member pointers.
4718  // TODO: maybe there should be a mangling for these
4719  if (T->getAs<MemberPointerType>())
4720    return;
4721
4722  if (T->isVectorType()) {
4723    // This matches gcc's encoding, even though technically it is
4724    // insufficient.
4725    // FIXME. We should do a better job than gcc.
4726    return;
4727  }
4728
4729  llvm_unreachable("@encode for type not implemented!");
4730}
4731
4732void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
4733                                                 std::string &S,
4734                                                 const FieldDecl *FD,
4735                                                 bool includeVBases) const {
4736  assert(RDecl && "Expected non-null RecordDecl");
4737  assert(!RDecl->isUnion() && "Should not be called for unions");
4738  if (!RDecl->getDefinition())
4739    return;
4740
4741  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
4742  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
4743  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
4744
4745  if (CXXRec) {
4746    for (CXXRecordDecl::base_class_iterator
4747           BI = CXXRec->bases_begin(),
4748           BE = CXXRec->bases_end(); BI != BE; ++BI) {
4749      if (!BI->isVirtual()) {
4750        CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4751        if (base->isEmpty())
4752          continue;
4753        uint64_t offs = layout.getBaseClassOffsetInBits(base);
4754        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4755                                  std::make_pair(offs, base));
4756      }
4757    }
4758  }
4759
4760  unsigned i = 0;
4761  for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4762                               FieldEnd = RDecl->field_end();
4763       Field != FieldEnd; ++Field, ++i) {
4764    uint64_t offs = layout.getFieldOffset(i);
4765    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4766                              std::make_pair(offs, *Field));
4767  }
4768
4769  if (CXXRec && includeVBases) {
4770    for (CXXRecordDecl::base_class_iterator
4771           BI = CXXRec->vbases_begin(),
4772           BE = CXXRec->vbases_end(); BI != BE; ++BI) {
4773      CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4774      if (base->isEmpty())
4775        continue;
4776      uint64_t offs = layout.getVBaseClassOffsetInBits(base);
4777      if (FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
4778        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
4779                                  std::make_pair(offs, base));
4780    }
4781  }
4782
4783  CharUnits size;
4784  if (CXXRec) {
4785    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
4786  } else {
4787    size = layout.getSize();
4788  }
4789
4790  uint64_t CurOffs = 0;
4791  std::multimap<uint64_t, NamedDecl *>::iterator
4792    CurLayObj = FieldOrBaseOffsets.begin();
4793
4794  if (CXXRec && CXXRec->isDynamicClass() &&
4795      (CurLayObj == FieldOrBaseOffsets.end() || CurLayObj->first != 0)) {
4796    if (FD) {
4797      S += "\"_vptr$";
4798      std::string recname = CXXRec->getNameAsString();
4799      if (recname.empty()) recname = "?";
4800      S += recname;
4801      S += '"';
4802    }
4803    S += "^^?";
4804    CurOffs += getTypeSize(VoidPtrTy);
4805  }
4806
4807  if (!RDecl->hasFlexibleArrayMember()) {
4808    // Mark the end of the structure.
4809    uint64_t offs = toBits(size);
4810    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4811                              std::make_pair(offs, (NamedDecl*)0));
4812  }
4813
4814  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
4815    assert(CurOffs <= CurLayObj->first);
4816
4817    if (CurOffs < CurLayObj->first) {
4818      uint64_t padding = CurLayObj->first - CurOffs;
4819      // FIXME: There doesn't seem to be a way to indicate in the encoding that
4820      // packing/alignment of members is different that normal, in which case
4821      // the encoding will be out-of-sync with the real layout.
4822      // If the runtime switches to just consider the size of types without
4823      // taking into account alignment, we could make padding explicit in the
4824      // encoding (e.g. using arrays of chars). The encoding strings would be
4825      // longer then though.
4826      CurOffs += padding;
4827    }
4828
4829    NamedDecl *dcl = CurLayObj->second;
4830    if (dcl == 0)
4831      break; // reached end of structure.
4832
4833    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
4834      // We expand the bases without their virtual bases since those are going
4835      // in the initial structure. Note that this differs from gcc which
4836      // expands virtual bases each time one is encountered in the hierarchy,
4837      // making the encoding type bigger than it really is.
4838      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false);
4839      assert(!base->isEmpty());
4840      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
4841    } else {
4842      FieldDecl *field = cast<FieldDecl>(dcl);
4843      if (FD) {
4844        S += '"';
4845        S += field->getNameAsString();
4846        S += '"';
4847      }
4848
4849      if (field->isBitField()) {
4850        EncodeBitField(this, S, field->getType(), field);
4851        CurOffs += field->getBitWidthValue(*this);
4852      } else {
4853        QualType qt = field->getType();
4854        getLegacyIntegralTypeEncoding(qt);
4855        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
4856                                   /*OutermostType*/false,
4857                                   /*EncodingProperty*/false,
4858                                   /*StructField*/true);
4859        CurOffs += getTypeSize(field->getType());
4860      }
4861    }
4862  }
4863}
4864
4865void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4866                                                 std::string& S) const {
4867  if (QT & Decl::OBJC_TQ_In)
4868    S += 'n';
4869  if (QT & Decl::OBJC_TQ_Inout)
4870    S += 'N';
4871  if (QT & Decl::OBJC_TQ_Out)
4872    S += 'o';
4873  if (QT & Decl::OBJC_TQ_Bycopy)
4874    S += 'O';
4875  if (QT & Decl::OBJC_TQ_Byref)
4876    S += 'R';
4877  if (QT & Decl::OBJC_TQ_Oneway)
4878    S += 'V';
4879}
4880
4881void ASTContext::setBuiltinVaListType(QualType T) {
4882  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4883
4884  BuiltinVaListType = T;
4885}
4886
4887TypedefDecl *ASTContext::getObjCIdDecl() const {
4888  if (!ObjCIdDecl) {
4889    QualType T = getObjCObjectType(ObjCBuiltinIdTy, 0, 0);
4890    T = getObjCObjectPointerType(T);
4891    TypeSourceInfo *IdInfo = getTrivialTypeSourceInfo(T);
4892    ObjCIdDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4893                                     getTranslationUnitDecl(),
4894                                     SourceLocation(), SourceLocation(),
4895                                     &Idents.get("id"), IdInfo);
4896  }
4897
4898  return ObjCIdDecl;
4899}
4900
4901TypedefDecl *ASTContext::getObjCSelDecl() const {
4902  if (!ObjCSelDecl) {
4903    QualType SelT = getPointerType(ObjCBuiltinSelTy);
4904    TypeSourceInfo *SelInfo = getTrivialTypeSourceInfo(SelT);
4905    ObjCSelDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4906                                      getTranslationUnitDecl(),
4907                                      SourceLocation(), SourceLocation(),
4908                                      &Idents.get("SEL"), SelInfo);
4909  }
4910  return ObjCSelDecl;
4911}
4912
4913TypedefDecl *ASTContext::getObjCClassDecl() const {
4914  if (!ObjCClassDecl) {
4915    QualType T = getObjCObjectType(ObjCBuiltinClassTy, 0, 0);
4916    T = getObjCObjectPointerType(T);
4917    TypeSourceInfo *ClassInfo = getTrivialTypeSourceInfo(T);
4918    ObjCClassDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4919                                        getTranslationUnitDecl(),
4920                                        SourceLocation(), SourceLocation(),
4921                                        &Idents.get("Class"), ClassInfo);
4922  }
4923
4924  return ObjCClassDecl;
4925}
4926
4927ObjCInterfaceDecl *ASTContext::getObjCProtocolDecl() const {
4928  if (!ObjCProtocolClassDecl) {
4929    ObjCProtocolClassDecl
4930      = ObjCInterfaceDecl::Create(*this, getTranslationUnitDecl(),
4931                                  SourceLocation(),
4932                                  &Idents.get("Protocol"),
4933                                  /*PrevDecl=*/0,
4934                                  SourceLocation(), true);
4935  }
4936
4937  return ObjCProtocolClassDecl;
4938}
4939
4940void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4941  assert(ObjCConstantStringType.isNull() &&
4942         "'NSConstantString' type already set!");
4943
4944  ObjCConstantStringType = getObjCInterfaceType(Decl);
4945}
4946
4947/// \brief Retrieve the template name that corresponds to a non-empty
4948/// lookup.
4949TemplateName
4950ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4951                                      UnresolvedSetIterator End) const {
4952  unsigned size = End - Begin;
4953  assert(size > 1 && "set is not overloaded!");
4954
4955  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4956                          size * sizeof(FunctionTemplateDecl*));
4957  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4958
4959  NamedDecl **Storage = OT->getStorage();
4960  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4961    NamedDecl *D = *I;
4962    assert(isa<FunctionTemplateDecl>(D) ||
4963           (isa<UsingShadowDecl>(D) &&
4964            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4965    *Storage++ = D;
4966  }
4967
4968  return TemplateName(OT);
4969}
4970
4971/// \brief Retrieve the template name that represents a qualified
4972/// template name such as \c std::vector.
4973TemplateName
4974ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4975                                     bool TemplateKeyword,
4976                                     TemplateDecl *Template) const {
4977  assert(NNS && "Missing nested-name-specifier in qualified template name");
4978
4979  // FIXME: Canonicalization?
4980  llvm::FoldingSetNodeID ID;
4981  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4982
4983  void *InsertPos = 0;
4984  QualifiedTemplateName *QTN =
4985    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4986  if (!QTN) {
4987    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4988    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4989  }
4990
4991  return TemplateName(QTN);
4992}
4993
4994/// \brief Retrieve the template name that represents a dependent
4995/// template name such as \c MetaFun::template apply.
4996TemplateName
4997ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4998                                     const IdentifierInfo *Name) const {
4999  assert((!NNS || NNS->isDependent()) &&
5000         "Nested name specifier must be dependent");
5001
5002  llvm::FoldingSetNodeID ID;
5003  DependentTemplateName::Profile(ID, NNS, Name);
5004
5005  void *InsertPos = 0;
5006  DependentTemplateName *QTN =
5007    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5008
5009  if (QTN)
5010    return TemplateName(QTN);
5011
5012  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
5013  if (CanonNNS == NNS) {
5014    QTN = new (*this,4) DependentTemplateName(NNS, Name);
5015  } else {
5016    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
5017    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
5018    DependentTemplateName *CheckQTN =
5019      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5020    assert(!CheckQTN && "Dependent type name canonicalization broken");
5021    (void)CheckQTN;
5022  }
5023
5024  DependentTemplateNames.InsertNode(QTN, InsertPos);
5025  return TemplateName(QTN);
5026}
5027
5028/// \brief Retrieve the template name that represents a dependent
5029/// template name such as \c MetaFun::template operator+.
5030TemplateName
5031ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
5032                                     OverloadedOperatorKind Operator) const {
5033  assert((!NNS || NNS->isDependent()) &&
5034         "Nested name specifier must be dependent");
5035
5036  llvm::FoldingSetNodeID ID;
5037  DependentTemplateName::Profile(ID, NNS, Operator);
5038
5039  void *InsertPos = 0;
5040  DependentTemplateName *QTN
5041    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5042
5043  if (QTN)
5044    return TemplateName(QTN);
5045
5046  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
5047  if (CanonNNS == NNS) {
5048    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
5049  } else {
5050    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
5051    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
5052
5053    DependentTemplateName *CheckQTN
5054      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5055    assert(!CheckQTN && "Dependent template name canonicalization broken");
5056    (void)CheckQTN;
5057  }
5058
5059  DependentTemplateNames.InsertNode(QTN, InsertPos);
5060  return TemplateName(QTN);
5061}
5062
5063TemplateName
5064ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
5065                                         TemplateName replacement) const {
5066  llvm::FoldingSetNodeID ID;
5067  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
5068
5069  void *insertPos = 0;
5070  SubstTemplateTemplateParmStorage *subst
5071    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
5072
5073  if (!subst) {
5074    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
5075    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
5076  }
5077
5078  return TemplateName(subst);
5079}
5080
5081TemplateName
5082ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
5083                                       const TemplateArgument &ArgPack) const {
5084  ASTContext &Self = const_cast<ASTContext &>(*this);
5085  llvm::FoldingSetNodeID ID;
5086  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
5087
5088  void *InsertPos = 0;
5089  SubstTemplateTemplateParmPackStorage *Subst
5090    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
5091
5092  if (!Subst) {
5093    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
5094                                                           ArgPack.pack_size(),
5095                                                         ArgPack.pack_begin());
5096    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
5097  }
5098
5099  return TemplateName(Subst);
5100}
5101
5102/// getFromTargetType - Given one of the integer types provided by
5103/// TargetInfo, produce the corresponding type. The unsigned @p Type
5104/// is actually a value of type @c TargetInfo::IntType.
5105CanQualType ASTContext::getFromTargetType(unsigned Type) const {
5106  switch (Type) {
5107  case TargetInfo::NoInt: return CanQualType();
5108  case TargetInfo::SignedShort: return ShortTy;
5109  case TargetInfo::UnsignedShort: return UnsignedShortTy;
5110  case TargetInfo::SignedInt: return IntTy;
5111  case TargetInfo::UnsignedInt: return UnsignedIntTy;
5112  case TargetInfo::SignedLong: return LongTy;
5113  case TargetInfo::UnsignedLong: return UnsignedLongTy;
5114  case TargetInfo::SignedLongLong: return LongLongTy;
5115  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
5116  }
5117
5118  llvm_unreachable("Unhandled TargetInfo::IntType value");
5119}
5120
5121//===----------------------------------------------------------------------===//
5122//                        Type Predicates.
5123//===----------------------------------------------------------------------===//
5124
5125/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
5126/// garbage collection attribute.
5127///
5128Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
5129  if (getLangOpts().getGC() == LangOptions::NonGC)
5130    return Qualifiers::GCNone;
5131
5132  assert(getLangOpts().ObjC1);
5133  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
5134
5135  // Default behaviour under objective-C's gc is for ObjC pointers
5136  // (or pointers to them) be treated as though they were declared
5137  // as __strong.
5138  if (GCAttrs == Qualifiers::GCNone) {
5139    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
5140      return Qualifiers::Strong;
5141    else if (Ty->isPointerType())
5142      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
5143  } else {
5144    // It's not valid to set GC attributes on anything that isn't a
5145    // pointer.
5146#ifndef NDEBUG
5147    QualType CT = Ty->getCanonicalTypeInternal();
5148    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
5149      CT = AT->getElementType();
5150    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
5151#endif
5152  }
5153  return GCAttrs;
5154}
5155
5156//===----------------------------------------------------------------------===//
5157//                        Type Compatibility Testing
5158//===----------------------------------------------------------------------===//
5159
5160/// areCompatVectorTypes - Return true if the two specified vector types are
5161/// compatible.
5162static bool areCompatVectorTypes(const VectorType *LHS,
5163                                 const VectorType *RHS) {
5164  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
5165  return LHS->getElementType() == RHS->getElementType() &&
5166         LHS->getNumElements() == RHS->getNumElements();
5167}
5168
5169bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
5170                                          QualType SecondVec) {
5171  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
5172  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
5173
5174  if (hasSameUnqualifiedType(FirstVec, SecondVec))
5175    return true;
5176
5177  // Treat Neon vector types and most AltiVec vector types as if they are the
5178  // equivalent GCC vector types.
5179  const VectorType *First = FirstVec->getAs<VectorType>();
5180  const VectorType *Second = SecondVec->getAs<VectorType>();
5181  if (First->getNumElements() == Second->getNumElements() &&
5182      hasSameType(First->getElementType(), Second->getElementType()) &&
5183      First->getVectorKind() != VectorType::AltiVecPixel &&
5184      First->getVectorKind() != VectorType::AltiVecBool &&
5185      Second->getVectorKind() != VectorType::AltiVecPixel &&
5186      Second->getVectorKind() != VectorType::AltiVecBool)
5187    return true;
5188
5189  return false;
5190}
5191
5192//===----------------------------------------------------------------------===//
5193// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
5194//===----------------------------------------------------------------------===//
5195
5196/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
5197/// inheritance hierarchy of 'rProto'.
5198bool
5199ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
5200                                           ObjCProtocolDecl *rProto) const {
5201  if (declaresSameEntity(lProto, rProto))
5202    return true;
5203  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
5204       E = rProto->protocol_end(); PI != E; ++PI)
5205    if (ProtocolCompatibleWithProtocol(lProto, *PI))
5206      return true;
5207  return false;
5208}
5209
5210/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
5211/// return true if lhs's protocols conform to rhs's protocol; false
5212/// otherwise.
5213bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
5214  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
5215    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
5216  return false;
5217}
5218
5219/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
5220/// Class<p1, ...>.
5221bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
5222                                                      QualType rhs) {
5223  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
5224  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5225  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
5226
5227  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5228       E = lhsQID->qual_end(); I != E; ++I) {
5229    bool match = false;
5230    ObjCProtocolDecl *lhsProto = *I;
5231    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5232         E = rhsOPT->qual_end(); J != E; ++J) {
5233      ObjCProtocolDecl *rhsProto = *J;
5234      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
5235        match = true;
5236        break;
5237      }
5238    }
5239    if (!match)
5240      return false;
5241  }
5242  return true;
5243}
5244
5245/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
5246/// ObjCQualifiedIDType.
5247bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
5248                                                   bool compare) {
5249  // Allow id<P..> and an 'id' or void* type in all cases.
5250  if (lhs->isVoidPointerType() ||
5251      lhs->isObjCIdType() || lhs->isObjCClassType())
5252    return true;
5253  else if (rhs->isVoidPointerType() ||
5254           rhs->isObjCIdType() || rhs->isObjCClassType())
5255    return true;
5256
5257  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
5258    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5259
5260    if (!rhsOPT) return false;
5261
5262    if (rhsOPT->qual_empty()) {
5263      // If the RHS is a unqualified interface pointer "NSString*",
5264      // make sure we check the class hierarchy.
5265      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5266        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5267             E = lhsQID->qual_end(); I != E; ++I) {
5268          // when comparing an id<P> on lhs with a static type on rhs,
5269          // see if static class implements all of id's protocols, directly or
5270          // through its super class and categories.
5271          if (!rhsID->ClassImplementsProtocol(*I, true))
5272            return false;
5273        }
5274      }
5275      // If there are no qualifiers and no interface, we have an 'id'.
5276      return true;
5277    }
5278    // Both the right and left sides have qualifiers.
5279    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5280         E = lhsQID->qual_end(); I != E; ++I) {
5281      ObjCProtocolDecl *lhsProto = *I;
5282      bool match = false;
5283
5284      // when comparing an id<P> on lhs with a static type on rhs,
5285      // see if static class implements all of id's protocols, directly or
5286      // through its super class and categories.
5287      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5288           E = rhsOPT->qual_end(); J != E; ++J) {
5289        ObjCProtocolDecl *rhsProto = *J;
5290        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5291            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5292          match = true;
5293          break;
5294        }
5295      }
5296      // If the RHS is a qualified interface pointer "NSString<P>*",
5297      // make sure we check the class hierarchy.
5298      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5299        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5300             E = lhsQID->qual_end(); I != E; ++I) {
5301          // when comparing an id<P> on lhs with a static type on rhs,
5302          // see if static class implements all of id's protocols, directly or
5303          // through its super class and categories.
5304          if (rhsID->ClassImplementsProtocol(*I, true)) {
5305            match = true;
5306            break;
5307          }
5308        }
5309      }
5310      if (!match)
5311        return false;
5312    }
5313
5314    return true;
5315  }
5316
5317  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
5318  assert(rhsQID && "One of the LHS/RHS should be id<x>");
5319
5320  if (const ObjCObjectPointerType *lhsOPT =
5321        lhs->getAsObjCInterfacePointerType()) {
5322    // If both the right and left sides have qualifiers.
5323    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
5324         E = lhsOPT->qual_end(); I != E; ++I) {
5325      ObjCProtocolDecl *lhsProto = *I;
5326      bool match = false;
5327
5328      // when comparing an id<P> on rhs with a static type on lhs,
5329      // see if static class implements all of id's protocols, directly or
5330      // through its super class and categories.
5331      // First, lhs protocols in the qualifier list must be found, direct
5332      // or indirect in rhs's qualifier list or it is a mismatch.
5333      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5334           E = rhsQID->qual_end(); J != E; ++J) {
5335        ObjCProtocolDecl *rhsProto = *J;
5336        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5337            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5338          match = true;
5339          break;
5340        }
5341      }
5342      if (!match)
5343        return false;
5344    }
5345
5346    // Static class's protocols, or its super class or category protocols
5347    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
5348    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
5349      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5350      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
5351      // This is rather dubious but matches gcc's behavior. If lhs has
5352      // no type qualifier and its class has no static protocol(s)
5353      // assume that it is mismatch.
5354      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
5355        return false;
5356      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5357           LHSInheritedProtocols.begin(),
5358           E = LHSInheritedProtocols.end(); I != E; ++I) {
5359        bool match = false;
5360        ObjCProtocolDecl *lhsProto = (*I);
5361        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5362             E = rhsQID->qual_end(); J != E; ++J) {
5363          ObjCProtocolDecl *rhsProto = *J;
5364          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5365              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5366            match = true;
5367            break;
5368          }
5369        }
5370        if (!match)
5371          return false;
5372      }
5373    }
5374    return true;
5375  }
5376  return false;
5377}
5378
5379/// canAssignObjCInterfaces - Return true if the two interface types are
5380/// compatible for assignment from RHS to LHS.  This handles validation of any
5381/// protocol qualifiers on the LHS or RHS.
5382///
5383bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
5384                                         const ObjCObjectPointerType *RHSOPT) {
5385  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5386  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5387
5388  // If either type represents the built-in 'id' or 'Class' types, return true.
5389  if (LHS->isObjCUnqualifiedIdOrClass() ||
5390      RHS->isObjCUnqualifiedIdOrClass())
5391    return true;
5392
5393  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
5394    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5395                                             QualType(RHSOPT,0),
5396                                             false);
5397
5398  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
5399    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
5400                                                QualType(RHSOPT,0));
5401
5402  // If we have 2 user-defined types, fall into that path.
5403  if (LHS->getInterface() && RHS->getInterface())
5404    return canAssignObjCInterfaces(LHS, RHS);
5405
5406  return false;
5407}
5408
5409/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
5410/// for providing type-safety for objective-c pointers used to pass/return
5411/// arguments in block literals. When passed as arguments, passing 'A*' where
5412/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
5413/// not OK. For the return type, the opposite is not OK.
5414bool ASTContext::canAssignObjCInterfacesInBlockPointer(
5415                                         const ObjCObjectPointerType *LHSOPT,
5416                                         const ObjCObjectPointerType *RHSOPT,
5417                                         bool BlockReturnType) {
5418  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
5419    return true;
5420
5421  if (LHSOPT->isObjCBuiltinType()) {
5422    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
5423  }
5424
5425  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
5426    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5427                                             QualType(RHSOPT,0),
5428                                             false);
5429
5430  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
5431  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
5432  if (LHS && RHS)  { // We have 2 user-defined types.
5433    if (LHS != RHS) {
5434      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
5435        return BlockReturnType;
5436      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
5437        return !BlockReturnType;
5438    }
5439    else
5440      return true;
5441  }
5442  return false;
5443}
5444
5445/// getIntersectionOfProtocols - This routine finds the intersection of set
5446/// of protocols inherited from two distinct objective-c pointer objects.
5447/// It is used to build composite qualifier list of the composite type of
5448/// the conditional expression involving two objective-c pointer objects.
5449static
5450void getIntersectionOfProtocols(ASTContext &Context,
5451                                const ObjCObjectPointerType *LHSOPT,
5452                                const ObjCObjectPointerType *RHSOPT,
5453      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
5454
5455  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5456  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5457  assert(LHS->getInterface() && "LHS must have an interface base");
5458  assert(RHS->getInterface() && "RHS must have an interface base");
5459
5460  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
5461  unsigned LHSNumProtocols = LHS->getNumProtocols();
5462  if (LHSNumProtocols > 0)
5463    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
5464  else {
5465    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5466    Context.CollectInheritedProtocols(LHS->getInterface(),
5467                                      LHSInheritedProtocols);
5468    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
5469                                LHSInheritedProtocols.end());
5470  }
5471
5472  unsigned RHSNumProtocols = RHS->getNumProtocols();
5473  if (RHSNumProtocols > 0) {
5474    ObjCProtocolDecl **RHSProtocols =
5475      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
5476    for (unsigned i = 0; i < RHSNumProtocols; ++i)
5477      if (InheritedProtocolSet.count(RHSProtocols[i]))
5478        IntersectionOfProtocols.push_back(RHSProtocols[i]);
5479  } else {
5480    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
5481    Context.CollectInheritedProtocols(RHS->getInterface(),
5482                                      RHSInheritedProtocols);
5483    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5484         RHSInheritedProtocols.begin(),
5485         E = RHSInheritedProtocols.end(); I != E; ++I)
5486      if (InheritedProtocolSet.count((*I)))
5487        IntersectionOfProtocols.push_back((*I));
5488  }
5489}
5490
5491/// areCommonBaseCompatible - Returns common base class of the two classes if
5492/// one found. Note that this is O'2 algorithm. But it will be called as the
5493/// last type comparison in a ?-exp of ObjC pointer types before a
5494/// warning is issued. So, its invokation is extremely rare.
5495QualType ASTContext::areCommonBaseCompatible(
5496                                          const ObjCObjectPointerType *Lptr,
5497                                          const ObjCObjectPointerType *Rptr) {
5498  const ObjCObjectType *LHS = Lptr->getObjectType();
5499  const ObjCObjectType *RHS = Rptr->getObjectType();
5500  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
5501  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
5502  if (!LDecl || !RDecl || (declaresSameEntity(LDecl, RDecl)))
5503    return QualType();
5504
5505  do {
5506    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
5507    if (canAssignObjCInterfaces(LHS, RHS)) {
5508      SmallVector<ObjCProtocolDecl *, 8> Protocols;
5509      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
5510
5511      QualType Result = QualType(LHS, 0);
5512      if (!Protocols.empty())
5513        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
5514      Result = getObjCObjectPointerType(Result);
5515      return Result;
5516    }
5517  } while ((LDecl = LDecl->getSuperClass()));
5518
5519  return QualType();
5520}
5521
5522bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
5523                                         const ObjCObjectType *RHS) {
5524  assert(LHS->getInterface() && "LHS is not an interface type");
5525  assert(RHS->getInterface() && "RHS is not an interface type");
5526
5527  // Verify that the base decls are compatible: the RHS must be a subclass of
5528  // the LHS.
5529  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
5530    return false;
5531
5532  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
5533  // protocol qualified at all, then we are good.
5534  if (LHS->getNumProtocols() == 0)
5535    return true;
5536
5537  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't,
5538  // more detailed analysis is required.
5539  if (RHS->getNumProtocols() == 0) {
5540    // OK, if LHS is a superclass of RHS *and*
5541    // this superclass is assignment compatible with LHS.
5542    // false otherwise.
5543    bool IsSuperClass =
5544      LHS->getInterface()->isSuperClassOf(RHS->getInterface());
5545    if (IsSuperClass) {
5546      // OK if conversion of LHS to SuperClass results in narrowing of types
5547      // ; i.e., SuperClass may implement at least one of the protocols
5548      // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
5549      // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
5550      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
5551      CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
5552      // If super class has no protocols, it is not a match.
5553      if (SuperClassInheritedProtocols.empty())
5554        return false;
5555
5556      for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5557           LHSPE = LHS->qual_end();
5558           LHSPI != LHSPE; LHSPI++) {
5559        bool SuperImplementsProtocol = false;
5560        ObjCProtocolDecl *LHSProto = (*LHSPI);
5561
5562        for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5563             SuperClassInheritedProtocols.begin(),
5564             E = SuperClassInheritedProtocols.end(); I != E; ++I) {
5565          ObjCProtocolDecl *SuperClassProto = (*I);
5566          if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
5567            SuperImplementsProtocol = true;
5568            break;
5569          }
5570        }
5571        if (!SuperImplementsProtocol)
5572          return false;
5573      }
5574      return true;
5575    }
5576    return false;
5577  }
5578
5579  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5580                                     LHSPE = LHS->qual_end();
5581       LHSPI != LHSPE; LHSPI++) {
5582    bool RHSImplementsProtocol = false;
5583
5584    // If the RHS doesn't implement the protocol on the left, the types
5585    // are incompatible.
5586    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
5587                                       RHSPE = RHS->qual_end();
5588         RHSPI != RHSPE; RHSPI++) {
5589      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
5590        RHSImplementsProtocol = true;
5591        break;
5592      }
5593    }
5594    // FIXME: For better diagnostics, consider passing back the protocol name.
5595    if (!RHSImplementsProtocol)
5596      return false;
5597  }
5598  // The RHS implements all protocols listed on the LHS.
5599  return true;
5600}
5601
5602bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
5603  // get the "pointed to" types
5604  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
5605  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
5606
5607  if (!LHSOPT || !RHSOPT)
5608    return false;
5609
5610  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
5611         canAssignObjCInterfaces(RHSOPT, LHSOPT);
5612}
5613
5614bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
5615  return canAssignObjCInterfaces(
5616                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
5617                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
5618}
5619
5620/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
5621/// both shall have the identically qualified version of a compatible type.
5622/// C99 6.2.7p1: Two types have compatible types if their types are the
5623/// same. See 6.7.[2,3,5] for additional rules.
5624bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
5625                                    bool CompareUnqualified) {
5626  if (getLangOpts().CPlusPlus)
5627    return hasSameType(LHS, RHS);
5628
5629  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
5630}
5631
5632bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
5633  return typesAreCompatible(LHS, RHS);
5634}
5635
5636bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
5637  return !mergeTypes(LHS, RHS, true).isNull();
5638}
5639
5640/// mergeTransparentUnionType - if T is a transparent union type and a member
5641/// of T is compatible with SubType, return the merged type, else return
5642/// QualType()
5643QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
5644                                               bool OfBlockPointer,
5645                                               bool Unqualified) {
5646  if (const RecordType *UT = T->getAsUnionType()) {
5647    RecordDecl *UD = UT->getDecl();
5648    if (UD->hasAttr<TransparentUnionAttr>()) {
5649      for (RecordDecl::field_iterator it = UD->field_begin(),
5650           itend = UD->field_end(); it != itend; ++it) {
5651        QualType ET = it->getType().getUnqualifiedType();
5652        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
5653        if (!MT.isNull())
5654          return MT;
5655      }
5656    }
5657  }
5658
5659  return QualType();
5660}
5661
5662/// mergeFunctionArgumentTypes - merge two types which appear as function
5663/// argument types
5664QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
5665                                                bool OfBlockPointer,
5666                                                bool Unqualified) {
5667  // GNU extension: two types are compatible if they appear as a function
5668  // argument, one of the types is a transparent union type and the other
5669  // type is compatible with a union member
5670  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
5671                                              Unqualified);
5672  if (!lmerge.isNull())
5673    return lmerge;
5674
5675  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
5676                                              Unqualified);
5677  if (!rmerge.isNull())
5678    return rmerge;
5679
5680  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
5681}
5682
5683QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
5684                                        bool OfBlockPointer,
5685                                        bool Unqualified) {
5686  const FunctionType *lbase = lhs->getAs<FunctionType>();
5687  const FunctionType *rbase = rhs->getAs<FunctionType>();
5688  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
5689  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
5690  bool allLTypes = true;
5691  bool allRTypes = true;
5692
5693  // Check return type
5694  QualType retType;
5695  if (OfBlockPointer) {
5696    QualType RHS = rbase->getResultType();
5697    QualType LHS = lbase->getResultType();
5698    bool UnqualifiedResult = Unqualified;
5699    if (!UnqualifiedResult)
5700      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
5701    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
5702  }
5703  else
5704    retType = mergeTypes(lbase->getResultType(), rbase->getResultType(), false,
5705                         Unqualified);
5706  if (retType.isNull()) return QualType();
5707
5708  if (Unqualified)
5709    retType = retType.getUnqualifiedType();
5710
5711  CanQualType LRetType = getCanonicalType(lbase->getResultType());
5712  CanQualType RRetType = getCanonicalType(rbase->getResultType());
5713  if (Unqualified) {
5714    LRetType = LRetType.getUnqualifiedType();
5715    RRetType = RRetType.getUnqualifiedType();
5716  }
5717
5718  if (getCanonicalType(retType) != LRetType)
5719    allLTypes = false;
5720  if (getCanonicalType(retType) != RRetType)
5721    allRTypes = false;
5722
5723  // FIXME: double check this
5724  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
5725  //                           rbase->getRegParmAttr() != 0 &&
5726  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
5727  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
5728  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
5729
5730  // Compatible functions must have compatible calling conventions
5731  if (!isSameCallConv(lbaseInfo.getCC(), rbaseInfo.getCC()))
5732    return QualType();
5733
5734  // Regparm is part of the calling convention.
5735  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
5736    return QualType();
5737  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
5738    return QualType();
5739
5740  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
5741    return QualType();
5742
5743  // functypes which return are preferred over those that do not.
5744  if (lbaseInfo.getNoReturn() && !rbaseInfo.getNoReturn())
5745    allLTypes = false;
5746  else if (!lbaseInfo.getNoReturn() && rbaseInfo.getNoReturn())
5747    allRTypes = false;
5748  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
5749  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
5750
5751  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
5752
5753  if (lproto && rproto) { // two C99 style function prototypes
5754    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
5755           "C++ shouldn't be here");
5756    unsigned lproto_nargs = lproto->getNumArgs();
5757    unsigned rproto_nargs = rproto->getNumArgs();
5758
5759    // Compatible functions must have the same number of arguments
5760    if (lproto_nargs != rproto_nargs)
5761      return QualType();
5762
5763    // Variadic and non-variadic functions aren't compatible
5764    if (lproto->isVariadic() != rproto->isVariadic())
5765      return QualType();
5766
5767    if (lproto->getTypeQuals() != rproto->getTypeQuals())
5768      return QualType();
5769
5770    if (LangOpts.ObjCAutoRefCount &&
5771        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
5772      return QualType();
5773
5774    // Check argument compatibility
5775    SmallVector<QualType, 10> types;
5776    for (unsigned i = 0; i < lproto_nargs; i++) {
5777      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
5778      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
5779      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
5780                                                    OfBlockPointer,
5781                                                    Unqualified);
5782      if (argtype.isNull()) return QualType();
5783
5784      if (Unqualified)
5785        argtype = argtype.getUnqualifiedType();
5786
5787      types.push_back(argtype);
5788      if (Unqualified) {
5789        largtype = largtype.getUnqualifiedType();
5790        rargtype = rargtype.getUnqualifiedType();
5791      }
5792
5793      if (getCanonicalType(argtype) != getCanonicalType(largtype))
5794        allLTypes = false;
5795      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
5796        allRTypes = false;
5797    }
5798
5799    if (allLTypes) return lhs;
5800    if (allRTypes) return rhs;
5801
5802    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
5803    EPI.ExtInfo = einfo;
5804    return getFunctionType(retType, types.begin(), types.size(), EPI);
5805  }
5806
5807  if (lproto) allRTypes = false;
5808  if (rproto) allLTypes = false;
5809
5810  const FunctionProtoType *proto = lproto ? lproto : rproto;
5811  if (proto) {
5812    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
5813    if (proto->isVariadic()) return QualType();
5814    // Check that the types are compatible with the types that
5815    // would result from default argument promotions (C99 6.7.5.3p15).
5816    // The only types actually affected are promotable integer
5817    // types and floats, which would be passed as a different
5818    // type depending on whether the prototype is visible.
5819    unsigned proto_nargs = proto->getNumArgs();
5820    for (unsigned i = 0; i < proto_nargs; ++i) {
5821      QualType argTy = proto->getArgType(i);
5822
5823      // Look at the promotion type of enum types, since that is the type used
5824      // to pass enum values.
5825      if (const EnumType *Enum = argTy->getAs<EnumType>())
5826        argTy = Enum->getDecl()->getPromotionType();
5827
5828      if (argTy->isPromotableIntegerType() ||
5829          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
5830        return QualType();
5831    }
5832
5833    if (allLTypes) return lhs;
5834    if (allRTypes) return rhs;
5835
5836    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
5837    EPI.ExtInfo = einfo;
5838    return getFunctionType(retType, proto->arg_type_begin(),
5839                           proto->getNumArgs(), EPI);
5840  }
5841
5842  if (allLTypes) return lhs;
5843  if (allRTypes) return rhs;
5844  return getFunctionNoProtoType(retType, einfo);
5845}
5846
5847QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
5848                                bool OfBlockPointer,
5849                                bool Unqualified, bool BlockReturnType) {
5850  // C++ [expr]: If an expression initially has the type "reference to T", the
5851  // type is adjusted to "T" prior to any further analysis, the expression
5852  // designates the object or function denoted by the reference, and the
5853  // expression is an lvalue unless the reference is an rvalue reference and
5854  // the expression is a function call (possibly inside parentheses).
5855  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
5856  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
5857
5858  if (Unqualified) {
5859    LHS = LHS.getUnqualifiedType();
5860    RHS = RHS.getUnqualifiedType();
5861  }
5862
5863  QualType LHSCan = getCanonicalType(LHS),
5864           RHSCan = getCanonicalType(RHS);
5865
5866  // If two types are identical, they are compatible.
5867  if (LHSCan == RHSCan)
5868    return LHS;
5869
5870  // If the qualifiers are different, the types aren't compatible... mostly.
5871  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5872  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5873  if (LQuals != RQuals) {
5874    // If any of these qualifiers are different, we have a type
5875    // mismatch.
5876    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5877        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
5878        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
5879      return QualType();
5880
5881    // Exactly one GC qualifier difference is allowed: __strong is
5882    // okay if the other type has no GC qualifier but is an Objective
5883    // C object pointer (i.e. implicitly strong by default).  We fix
5884    // this by pretending that the unqualified type was actually
5885    // qualified __strong.
5886    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5887    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5888    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5889
5890    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5891      return QualType();
5892
5893    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
5894      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
5895    }
5896    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
5897      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
5898    }
5899    return QualType();
5900  }
5901
5902  // Okay, qualifiers are equal.
5903
5904  Type::TypeClass LHSClass = LHSCan->getTypeClass();
5905  Type::TypeClass RHSClass = RHSCan->getTypeClass();
5906
5907  // We want to consider the two function types to be the same for these
5908  // comparisons, just force one to the other.
5909  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
5910  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
5911
5912  // Same as above for arrays
5913  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
5914    LHSClass = Type::ConstantArray;
5915  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
5916    RHSClass = Type::ConstantArray;
5917
5918  // ObjCInterfaces are just specialized ObjCObjects.
5919  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
5920  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
5921
5922  // Canonicalize ExtVector -> Vector.
5923  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
5924  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
5925
5926  // If the canonical type classes don't match.
5927  if (LHSClass != RHSClass) {
5928    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
5929    // a signed integer type, or an unsigned integer type.
5930    // Compatibility is based on the underlying type, not the promotion
5931    // type.
5932    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
5933      QualType TINT = ETy->getDecl()->getIntegerType();
5934      if (!TINT.isNull() && hasSameType(TINT, RHSCan.getUnqualifiedType()))
5935        return RHS;
5936    }
5937    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
5938      QualType TINT = ETy->getDecl()->getIntegerType();
5939      if (!TINT.isNull() && hasSameType(TINT, LHSCan.getUnqualifiedType()))
5940        return LHS;
5941    }
5942    // allow block pointer type to match an 'id' type.
5943    if (OfBlockPointer && !BlockReturnType) {
5944       if (LHS->isObjCIdType() && RHS->isBlockPointerType())
5945         return LHS;
5946      if (RHS->isObjCIdType() && LHS->isBlockPointerType())
5947        return RHS;
5948    }
5949
5950    return QualType();
5951  }
5952
5953  // The canonical type classes match.
5954  switch (LHSClass) {
5955#define TYPE(Class, Base)
5956#define ABSTRACT_TYPE(Class, Base)
5957#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
5958#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
5959#define DEPENDENT_TYPE(Class, Base) case Type::Class:
5960#include "clang/AST/TypeNodes.def"
5961    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
5962
5963  case Type::LValueReference:
5964  case Type::RValueReference:
5965  case Type::MemberPointer:
5966    llvm_unreachable("C++ should never be in mergeTypes");
5967
5968  case Type::ObjCInterface:
5969  case Type::IncompleteArray:
5970  case Type::VariableArray:
5971  case Type::FunctionProto:
5972  case Type::ExtVector:
5973    llvm_unreachable("Types are eliminated above");
5974
5975  case Type::Pointer:
5976  {
5977    // Merge two pointer types, while trying to preserve typedef info
5978    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
5979    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
5980    if (Unqualified) {
5981      LHSPointee = LHSPointee.getUnqualifiedType();
5982      RHSPointee = RHSPointee.getUnqualifiedType();
5983    }
5984    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
5985                                     Unqualified);
5986    if (ResultType.isNull()) return QualType();
5987    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5988      return LHS;
5989    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5990      return RHS;
5991    return getPointerType(ResultType);
5992  }
5993  case Type::BlockPointer:
5994  {
5995    // Merge two block pointer types, while trying to preserve typedef info
5996    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
5997    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
5998    if (Unqualified) {
5999      LHSPointee = LHSPointee.getUnqualifiedType();
6000      RHSPointee = RHSPointee.getUnqualifiedType();
6001    }
6002    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
6003                                     Unqualified);
6004    if (ResultType.isNull()) return QualType();
6005    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
6006      return LHS;
6007    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
6008      return RHS;
6009    return getBlockPointerType(ResultType);
6010  }
6011  case Type::Atomic:
6012  {
6013    // Merge two pointer types, while trying to preserve typedef info
6014    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
6015    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
6016    if (Unqualified) {
6017      LHSValue = LHSValue.getUnqualifiedType();
6018      RHSValue = RHSValue.getUnqualifiedType();
6019    }
6020    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
6021                                     Unqualified);
6022    if (ResultType.isNull()) return QualType();
6023    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
6024      return LHS;
6025    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
6026      return RHS;
6027    return getAtomicType(ResultType);
6028  }
6029  case Type::ConstantArray:
6030  {
6031    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
6032    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
6033    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
6034      return QualType();
6035
6036    QualType LHSElem = getAsArrayType(LHS)->getElementType();
6037    QualType RHSElem = getAsArrayType(RHS)->getElementType();
6038    if (Unqualified) {
6039      LHSElem = LHSElem.getUnqualifiedType();
6040      RHSElem = RHSElem.getUnqualifiedType();
6041    }
6042
6043    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
6044    if (ResultType.isNull()) return QualType();
6045    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
6046      return LHS;
6047    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
6048      return RHS;
6049    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
6050                                          ArrayType::ArraySizeModifier(), 0);
6051    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
6052                                          ArrayType::ArraySizeModifier(), 0);
6053    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
6054    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
6055    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
6056      return LHS;
6057    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
6058      return RHS;
6059    if (LVAT) {
6060      // FIXME: This isn't correct! But tricky to implement because
6061      // the array's size has to be the size of LHS, but the type
6062      // has to be different.
6063      return LHS;
6064    }
6065    if (RVAT) {
6066      // FIXME: This isn't correct! But tricky to implement because
6067      // the array's size has to be the size of RHS, but the type
6068      // has to be different.
6069      return RHS;
6070    }
6071    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
6072    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
6073    return getIncompleteArrayType(ResultType,
6074                                  ArrayType::ArraySizeModifier(), 0);
6075  }
6076  case Type::FunctionNoProto:
6077    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
6078  case Type::Record:
6079  case Type::Enum:
6080    return QualType();
6081  case Type::Builtin:
6082    // Only exactly equal builtin types are compatible, which is tested above.
6083    return QualType();
6084  case Type::Complex:
6085    // Distinct complex types are incompatible.
6086    return QualType();
6087  case Type::Vector:
6088    // FIXME: The merged type should be an ExtVector!
6089    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
6090                             RHSCan->getAs<VectorType>()))
6091      return LHS;
6092    return QualType();
6093  case Type::ObjCObject: {
6094    // Check if the types are assignment compatible.
6095    // FIXME: This should be type compatibility, e.g. whether
6096    // "LHS x; RHS x;" at global scope is legal.
6097    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
6098    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
6099    if (canAssignObjCInterfaces(LHSIface, RHSIface))
6100      return LHS;
6101
6102    return QualType();
6103  }
6104  case Type::ObjCObjectPointer: {
6105    if (OfBlockPointer) {
6106      if (canAssignObjCInterfacesInBlockPointer(
6107                                          LHS->getAs<ObjCObjectPointerType>(),
6108                                          RHS->getAs<ObjCObjectPointerType>(),
6109                                          BlockReturnType))
6110        return LHS;
6111      return QualType();
6112    }
6113    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
6114                                RHS->getAs<ObjCObjectPointerType>()))
6115      return LHS;
6116
6117    return QualType();
6118  }
6119  }
6120
6121  llvm_unreachable("Invalid Type::Class!");
6122}
6123
6124bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
6125                   const FunctionProtoType *FromFunctionType,
6126                   const FunctionProtoType *ToFunctionType) {
6127  if (FromFunctionType->hasAnyConsumedArgs() !=
6128      ToFunctionType->hasAnyConsumedArgs())
6129    return false;
6130  FunctionProtoType::ExtProtoInfo FromEPI =
6131    FromFunctionType->getExtProtoInfo();
6132  FunctionProtoType::ExtProtoInfo ToEPI =
6133    ToFunctionType->getExtProtoInfo();
6134  if (FromEPI.ConsumedArguments && ToEPI.ConsumedArguments)
6135    for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs();
6136         ArgIdx != NumArgs; ++ArgIdx)  {
6137      if (FromEPI.ConsumedArguments[ArgIdx] !=
6138          ToEPI.ConsumedArguments[ArgIdx])
6139        return false;
6140    }
6141  return true;
6142}
6143
6144/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
6145/// 'RHS' attributes and returns the merged version; including for function
6146/// return types.
6147QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
6148  QualType LHSCan = getCanonicalType(LHS),
6149  RHSCan = getCanonicalType(RHS);
6150  // If two types are identical, they are compatible.
6151  if (LHSCan == RHSCan)
6152    return LHS;
6153  if (RHSCan->isFunctionType()) {
6154    if (!LHSCan->isFunctionType())
6155      return QualType();
6156    QualType OldReturnType =
6157      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
6158    QualType NewReturnType =
6159      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
6160    QualType ResReturnType =
6161      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
6162    if (ResReturnType.isNull())
6163      return QualType();
6164    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
6165      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
6166      // In either case, use OldReturnType to build the new function type.
6167      const FunctionType *F = LHS->getAs<FunctionType>();
6168      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
6169        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
6170        EPI.ExtInfo = getFunctionExtInfo(LHS);
6171        QualType ResultType
6172          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
6173                            FPT->getNumArgs(), EPI);
6174        return ResultType;
6175      }
6176    }
6177    return QualType();
6178  }
6179
6180  // If the qualifiers are different, the types can still be merged.
6181  Qualifiers LQuals = LHSCan.getLocalQualifiers();
6182  Qualifiers RQuals = RHSCan.getLocalQualifiers();
6183  if (LQuals != RQuals) {
6184    // If any of these qualifiers are different, we have a type mismatch.
6185    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
6186        LQuals.getAddressSpace() != RQuals.getAddressSpace())
6187      return QualType();
6188
6189    // Exactly one GC qualifier difference is allowed: __strong is
6190    // okay if the other type has no GC qualifier but is an Objective
6191    // C object pointer (i.e. implicitly strong by default).  We fix
6192    // this by pretending that the unqualified type was actually
6193    // qualified __strong.
6194    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
6195    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
6196    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
6197
6198    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
6199      return QualType();
6200
6201    if (GC_L == Qualifiers::Strong)
6202      return LHS;
6203    if (GC_R == Qualifiers::Strong)
6204      return RHS;
6205    return QualType();
6206  }
6207
6208  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
6209    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6210    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6211    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
6212    if (ResQT == LHSBaseQT)
6213      return LHS;
6214    if (ResQT == RHSBaseQT)
6215      return RHS;
6216  }
6217  return QualType();
6218}
6219
6220//===----------------------------------------------------------------------===//
6221//                         Integer Predicates
6222//===----------------------------------------------------------------------===//
6223
6224unsigned ASTContext::getIntWidth(QualType T) const {
6225  if (const EnumType *ET = dyn_cast<EnumType>(T))
6226    T = ET->getDecl()->getIntegerType();
6227  if (T->isBooleanType())
6228    return 1;
6229  // For builtin types, just use the standard type sizing method
6230  return (unsigned)getTypeSize(T);
6231}
6232
6233QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
6234  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
6235
6236  // Turn <4 x signed int> -> <4 x unsigned int>
6237  if (const VectorType *VTy = T->getAs<VectorType>())
6238    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
6239                         VTy->getNumElements(), VTy->getVectorKind());
6240
6241  // For enums, we return the unsigned version of the base type.
6242  if (const EnumType *ETy = T->getAs<EnumType>())
6243    T = ETy->getDecl()->getIntegerType();
6244
6245  const BuiltinType *BTy = T->getAs<BuiltinType>();
6246  assert(BTy && "Unexpected signed integer type");
6247  switch (BTy->getKind()) {
6248  case BuiltinType::Char_S:
6249  case BuiltinType::SChar:
6250    return UnsignedCharTy;
6251  case BuiltinType::Short:
6252    return UnsignedShortTy;
6253  case BuiltinType::Int:
6254    return UnsignedIntTy;
6255  case BuiltinType::Long:
6256    return UnsignedLongTy;
6257  case BuiltinType::LongLong:
6258    return UnsignedLongLongTy;
6259  case BuiltinType::Int128:
6260    return UnsignedInt128Ty;
6261  default:
6262    llvm_unreachable("Unexpected signed integer type");
6263  }
6264}
6265
6266ASTMutationListener::~ASTMutationListener() { }
6267
6268
6269//===----------------------------------------------------------------------===//
6270//                          Builtin Type Computation
6271//===----------------------------------------------------------------------===//
6272
6273/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
6274/// pointer over the consumed characters.  This returns the resultant type.  If
6275/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
6276/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
6277/// a vector of "i*".
6278///
6279/// RequiresICE is filled in on return to indicate whether the value is required
6280/// to be an Integer Constant Expression.
6281static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
6282                                  ASTContext::GetBuiltinTypeError &Error,
6283                                  bool &RequiresICE,
6284                                  bool AllowTypeModifiers) {
6285  // Modifiers.
6286  int HowLong = 0;
6287  bool Signed = false, Unsigned = false;
6288  RequiresICE = false;
6289
6290  // Read the prefixed modifiers first.
6291  bool Done = false;
6292  while (!Done) {
6293    switch (*Str++) {
6294    default: Done = true; --Str; break;
6295    case 'I':
6296      RequiresICE = true;
6297      break;
6298    case 'S':
6299      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
6300      assert(!Signed && "Can't use 'S' modifier multiple times!");
6301      Signed = true;
6302      break;
6303    case 'U':
6304      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
6305      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
6306      Unsigned = true;
6307      break;
6308    case 'L':
6309      assert(HowLong <= 2 && "Can't have LLLL modifier");
6310      ++HowLong;
6311      break;
6312    }
6313  }
6314
6315  QualType Type;
6316
6317  // Read the base type.
6318  switch (*Str++) {
6319  default: llvm_unreachable("Unknown builtin type letter!");
6320  case 'v':
6321    assert(HowLong == 0 && !Signed && !Unsigned &&
6322           "Bad modifiers used with 'v'!");
6323    Type = Context.VoidTy;
6324    break;
6325  case 'f':
6326    assert(HowLong == 0 && !Signed && !Unsigned &&
6327           "Bad modifiers used with 'f'!");
6328    Type = Context.FloatTy;
6329    break;
6330  case 'd':
6331    assert(HowLong < 2 && !Signed && !Unsigned &&
6332           "Bad modifiers used with 'd'!");
6333    if (HowLong)
6334      Type = Context.LongDoubleTy;
6335    else
6336      Type = Context.DoubleTy;
6337    break;
6338  case 's':
6339    assert(HowLong == 0 && "Bad modifiers used with 's'!");
6340    if (Unsigned)
6341      Type = Context.UnsignedShortTy;
6342    else
6343      Type = Context.ShortTy;
6344    break;
6345  case 'i':
6346    if (HowLong == 3)
6347      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
6348    else if (HowLong == 2)
6349      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
6350    else if (HowLong == 1)
6351      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
6352    else
6353      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
6354    break;
6355  case 'c':
6356    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
6357    if (Signed)
6358      Type = Context.SignedCharTy;
6359    else if (Unsigned)
6360      Type = Context.UnsignedCharTy;
6361    else
6362      Type = Context.CharTy;
6363    break;
6364  case 'b': // boolean
6365    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
6366    Type = Context.BoolTy;
6367    break;
6368  case 'z':  // size_t.
6369    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
6370    Type = Context.getSizeType();
6371    break;
6372  case 'F':
6373    Type = Context.getCFConstantStringType();
6374    break;
6375  case 'G':
6376    Type = Context.getObjCIdType();
6377    break;
6378  case 'H':
6379    Type = Context.getObjCSelType();
6380    break;
6381  case 'a':
6382    Type = Context.getBuiltinVaListType();
6383    assert(!Type.isNull() && "builtin va list type not initialized!");
6384    break;
6385  case 'A':
6386    // This is a "reference" to a va_list; however, what exactly
6387    // this means depends on how va_list is defined. There are two
6388    // different kinds of va_list: ones passed by value, and ones
6389    // passed by reference.  An example of a by-value va_list is
6390    // x86, where va_list is a char*. An example of by-ref va_list
6391    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
6392    // we want this argument to be a char*&; for x86-64, we want
6393    // it to be a __va_list_tag*.
6394    Type = Context.getBuiltinVaListType();
6395    assert(!Type.isNull() && "builtin va list type not initialized!");
6396    if (Type->isArrayType())
6397      Type = Context.getArrayDecayedType(Type);
6398    else
6399      Type = Context.getLValueReferenceType(Type);
6400    break;
6401  case 'V': {
6402    char *End;
6403    unsigned NumElements = strtoul(Str, &End, 10);
6404    assert(End != Str && "Missing vector size");
6405    Str = End;
6406
6407    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
6408                                             RequiresICE, false);
6409    assert(!RequiresICE && "Can't require vector ICE");
6410
6411    // TODO: No way to make AltiVec vectors in builtins yet.
6412    Type = Context.getVectorType(ElementType, NumElements,
6413                                 VectorType::GenericVector);
6414    break;
6415  }
6416  case 'X': {
6417    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
6418                                             false);
6419    assert(!RequiresICE && "Can't require complex ICE");
6420    Type = Context.getComplexType(ElementType);
6421    break;
6422  }
6423  case 'Y' : {
6424    Type = Context.getPointerDiffType();
6425    break;
6426  }
6427  case 'P':
6428    Type = Context.getFILEType();
6429    if (Type.isNull()) {
6430      Error = ASTContext::GE_Missing_stdio;
6431      return QualType();
6432    }
6433    break;
6434  case 'J':
6435    if (Signed)
6436      Type = Context.getsigjmp_bufType();
6437    else
6438      Type = Context.getjmp_bufType();
6439
6440    if (Type.isNull()) {
6441      Error = ASTContext::GE_Missing_setjmp;
6442      return QualType();
6443    }
6444    break;
6445  case 'K':
6446    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'K'!");
6447    Type = Context.getucontext_tType();
6448
6449    if (Type.isNull()) {
6450      Error = ASTContext::GE_Missing_ucontext;
6451      return QualType();
6452    }
6453    break;
6454  }
6455
6456  // If there are modifiers and if we're allowed to parse them, go for it.
6457  Done = !AllowTypeModifiers;
6458  while (!Done) {
6459    switch (char c = *Str++) {
6460    default: Done = true; --Str; break;
6461    case '*':
6462    case '&': {
6463      // Both pointers and references can have their pointee types
6464      // qualified with an address space.
6465      char *End;
6466      unsigned AddrSpace = strtoul(Str, &End, 10);
6467      if (End != Str && AddrSpace != 0) {
6468        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
6469        Str = End;
6470      }
6471      if (c == '*')
6472        Type = Context.getPointerType(Type);
6473      else
6474        Type = Context.getLValueReferenceType(Type);
6475      break;
6476    }
6477    // FIXME: There's no way to have a built-in with an rvalue ref arg.
6478    case 'C':
6479      Type = Type.withConst();
6480      break;
6481    case 'D':
6482      Type = Context.getVolatileType(Type);
6483      break;
6484    case 'R':
6485      Type = Type.withRestrict();
6486      break;
6487    }
6488  }
6489
6490  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
6491         "Integer constant 'I' type must be an integer");
6492
6493  return Type;
6494}
6495
6496/// GetBuiltinType - Return the type for the specified builtin.
6497QualType ASTContext::GetBuiltinType(unsigned Id,
6498                                    GetBuiltinTypeError &Error,
6499                                    unsigned *IntegerConstantArgs) const {
6500  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
6501
6502  SmallVector<QualType, 8> ArgTypes;
6503
6504  bool RequiresICE = false;
6505  Error = GE_None;
6506  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
6507                                       RequiresICE, true);
6508  if (Error != GE_None)
6509    return QualType();
6510
6511  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
6512
6513  while (TypeStr[0] && TypeStr[0] != '.') {
6514    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
6515    if (Error != GE_None)
6516      return QualType();
6517
6518    // If this argument is required to be an IntegerConstantExpression and the
6519    // caller cares, fill in the bitmask we return.
6520    if (RequiresICE && IntegerConstantArgs)
6521      *IntegerConstantArgs |= 1 << ArgTypes.size();
6522
6523    // Do array -> pointer decay.  The builtin should use the decayed type.
6524    if (Ty->isArrayType())
6525      Ty = getArrayDecayedType(Ty);
6526
6527    ArgTypes.push_back(Ty);
6528  }
6529
6530  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
6531         "'.' should only occur at end of builtin type list!");
6532
6533  FunctionType::ExtInfo EI;
6534  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
6535
6536  bool Variadic = (TypeStr[0] == '.');
6537
6538  // We really shouldn't be making a no-proto type here, especially in C++.
6539  if (ArgTypes.empty() && Variadic)
6540    return getFunctionNoProtoType(ResType, EI);
6541
6542  FunctionProtoType::ExtProtoInfo EPI;
6543  EPI.ExtInfo = EI;
6544  EPI.Variadic = Variadic;
6545
6546  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(), EPI);
6547}
6548
6549GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
6550  GVALinkage External = GVA_StrongExternal;
6551
6552  Linkage L = FD->getLinkage();
6553  switch (L) {
6554  case NoLinkage:
6555  case InternalLinkage:
6556  case UniqueExternalLinkage:
6557    return GVA_Internal;
6558
6559  case ExternalLinkage:
6560    switch (FD->getTemplateSpecializationKind()) {
6561    case TSK_Undeclared:
6562    case TSK_ExplicitSpecialization:
6563      External = GVA_StrongExternal;
6564      break;
6565
6566    case TSK_ExplicitInstantiationDefinition:
6567      return GVA_ExplicitTemplateInstantiation;
6568
6569    case TSK_ExplicitInstantiationDeclaration:
6570    case TSK_ImplicitInstantiation:
6571      External = GVA_TemplateInstantiation;
6572      break;
6573    }
6574  }
6575
6576  if (!FD->isInlined())
6577    return External;
6578
6579  if (!getLangOpts().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
6580    // GNU or C99 inline semantics. Determine whether this symbol should be
6581    // externally visible.
6582    if (FD->isInlineDefinitionExternallyVisible())
6583      return External;
6584
6585    // C99 inline semantics, where the symbol is not externally visible.
6586    return GVA_C99Inline;
6587  }
6588
6589  // C++0x [temp.explicit]p9:
6590  //   [ Note: The intent is that an inline function that is the subject of
6591  //   an explicit instantiation declaration will still be implicitly
6592  //   instantiated when used so that the body can be considered for
6593  //   inlining, but that no out-of-line copy of the inline function would be
6594  //   generated in the translation unit. -- end note ]
6595  if (FD->getTemplateSpecializationKind()
6596                                       == TSK_ExplicitInstantiationDeclaration)
6597    return GVA_C99Inline;
6598
6599  return GVA_CXXInline;
6600}
6601
6602GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
6603  // If this is a static data member, compute the kind of template
6604  // specialization. Otherwise, this variable is not part of a
6605  // template.
6606  TemplateSpecializationKind TSK = TSK_Undeclared;
6607  if (VD->isStaticDataMember())
6608    TSK = VD->getTemplateSpecializationKind();
6609
6610  Linkage L = VD->getLinkage();
6611  if (L == ExternalLinkage && getLangOpts().CPlusPlus &&
6612      VD->getType()->getLinkage() == UniqueExternalLinkage)
6613    L = UniqueExternalLinkage;
6614
6615  switch (L) {
6616  case NoLinkage:
6617  case InternalLinkage:
6618  case UniqueExternalLinkage:
6619    return GVA_Internal;
6620
6621  case ExternalLinkage:
6622    switch (TSK) {
6623    case TSK_Undeclared:
6624    case TSK_ExplicitSpecialization:
6625      return GVA_StrongExternal;
6626
6627    case TSK_ExplicitInstantiationDeclaration:
6628      llvm_unreachable("Variable should not be instantiated");
6629      // Fall through to treat this like any other instantiation.
6630
6631    case TSK_ExplicitInstantiationDefinition:
6632      return GVA_ExplicitTemplateInstantiation;
6633
6634    case TSK_ImplicitInstantiation:
6635      return GVA_TemplateInstantiation;
6636    }
6637  }
6638
6639  llvm_unreachable("Invalid Linkage!");
6640}
6641
6642bool ASTContext::DeclMustBeEmitted(const Decl *D) {
6643  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
6644    if (!VD->isFileVarDecl())
6645      return false;
6646  } else if (!isa<FunctionDecl>(D))
6647    return false;
6648
6649  // Weak references don't produce any output by themselves.
6650  if (D->hasAttr<WeakRefAttr>())
6651    return false;
6652
6653  // Aliases and used decls are required.
6654  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
6655    return true;
6656
6657  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
6658    // Forward declarations aren't required.
6659    if (!FD->doesThisDeclarationHaveABody())
6660      return FD->doesDeclarationForceExternallyVisibleDefinition();
6661
6662    // Constructors and destructors are required.
6663    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
6664      return true;
6665
6666    // The key function for a class is required.
6667    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
6668      const CXXRecordDecl *RD = MD->getParent();
6669      if (MD->isOutOfLine() && RD->isDynamicClass()) {
6670        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
6671        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
6672          return true;
6673      }
6674    }
6675
6676    GVALinkage Linkage = GetGVALinkageForFunction(FD);
6677
6678    // static, static inline, always_inline, and extern inline functions can
6679    // always be deferred.  Normal inline functions can be deferred in C99/C++.
6680    // Implicit template instantiations can also be deferred in C++.
6681    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
6682        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
6683      return false;
6684    return true;
6685  }
6686
6687  const VarDecl *VD = cast<VarDecl>(D);
6688  assert(VD->isFileVarDecl() && "Expected file scoped var");
6689
6690  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
6691    return false;
6692
6693  // Structs that have non-trivial constructors or destructors are required.
6694
6695  // FIXME: Handle references.
6696  // FIXME: Be more selective about which constructors we care about.
6697  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
6698    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
6699      if (RD->hasDefinition() && !(RD->hasTrivialDefaultConstructor() &&
6700                                   RD->hasTrivialCopyConstructor() &&
6701                                   RD->hasTrivialMoveConstructor() &&
6702                                   RD->hasTrivialDestructor()))
6703        return true;
6704    }
6705  }
6706
6707  GVALinkage L = GetGVALinkageForVariable(VD);
6708  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
6709    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
6710      return false;
6711  }
6712
6713  return true;
6714}
6715
6716CallingConv ASTContext::getDefaultMethodCallConv() {
6717  // Pass through to the C++ ABI object
6718  return ABI->getDefaultMethodCallConv();
6719}
6720
6721bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
6722  // Pass through to the C++ ABI object
6723  return ABI->isNearlyEmpty(RD);
6724}
6725
6726MangleContext *ASTContext::createMangleContext() {
6727  switch (Target->getCXXABI()) {
6728  case CXXABI_ARM:
6729  case CXXABI_Itanium:
6730    return createItaniumMangleContext(*this, getDiagnostics());
6731  case CXXABI_Microsoft:
6732    return createMicrosoftMangleContext(*this, getDiagnostics());
6733  }
6734  llvm_unreachable("Unsupported ABI");
6735}
6736
6737CXXABI::~CXXABI() {}
6738
6739size_t ASTContext::getSideTableAllocatedMemory() const {
6740  return ASTRecordLayouts.getMemorySize()
6741    + llvm::capacity_in_bytes(ObjCLayouts)
6742    + llvm::capacity_in_bytes(KeyFunctions)
6743    + llvm::capacity_in_bytes(ObjCImpls)
6744    + llvm::capacity_in_bytes(BlockVarCopyInits)
6745    + llvm::capacity_in_bytes(DeclAttrs)
6746    + llvm::capacity_in_bytes(InstantiatedFromStaticDataMember)
6747    + llvm::capacity_in_bytes(InstantiatedFromUsingDecl)
6748    + llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl)
6749    + llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl)
6750    + llvm::capacity_in_bytes(OverriddenMethods)
6751    + llvm::capacity_in_bytes(Types)
6752    + llvm::capacity_in_bytes(VariableArrayTypes)
6753    + llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
6754}
6755
6756unsigned ASTContext::getLambdaManglingNumber(CXXMethodDecl *CallOperator) {
6757  CXXRecordDecl *Lambda = CallOperator->getParent();
6758  return LambdaMangleContexts[Lambda->getDeclContext()]
6759           .getManglingNumber(CallOperator);
6760}
6761
6762
6763void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
6764  ParamIndices[D] = index;
6765}
6766
6767unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
6768  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
6769  assert(I != ParamIndices.end() &&
6770         "ParmIndices lacks entry set by ParmVarDecl");
6771  return I->second;
6772}
6773