ASTContext.cpp revision 2be460723940f8184ec36529b6f6ddf59c04e411 
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  FloatRank, DoubleRank, LongDoubleRank
54};
55
56void
57ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
58                                               TemplateTemplateParmDecl *Parm) {
59  ID.AddInteger(Parm->getDepth());
60  ID.AddInteger(Parm->getPosition());
61  ID.AddBoolean(Parm->isParameterPack());
62
63  TemplateParameterList *Params = Parm->getTemplateParameters();
64  ID.AddInteger(Params->size());
65  for (TemplateParameterList::const_iterator P = Params->begin(),
66                                          PEnd = Params->end();
67       P != PEnd; ++P) {
68    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
69      ID.AddInteger(0);
70      ID.AddBoolean(TTP->isParameterPack());
71      continue;
72    }
73
74    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
75      ID.AddInteger(1);
76      ID.AddBoolean(NTTP->isParameterPack());
77      ID.AddPointer(NTTP->getType().getAsOpaquePtr());
78      if (NTTP->isExpandedParameterPack()) {
79        ID.AddBoolean(true);
80        ID.AddInteger(NTTP->getNumExpansionTypes());
81        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I)
82          ID.AddPointer(NTTP->getExpansionType(I).getAsOpaquePtr());
83      } else
84        ID.AddBoolean(false);
85      continue;
86    }
87
88    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
89    ID.AddInteger(2);
90    Profile(ID, TTP);
91  }
92}
93
94TemplateTemplateParmDecl *
95ASTContext::getCanonicalTemplateTemplateParmDecl(
96                                          TemplateTemplateParmDecl *TTP) const {
97  // Check if we already have a canonical template template parameter.
98  llvm::FoldingSetNodeID ID;
99  CanonicalTemplateTemplateParm::Profile(ID, TTP);
100  void *InsertPos = 0;
101  CanonicalTemplateTemplateParm *Canonical
102    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
103  if (Canonical)
104    return Canonical->getParam();
105
106  // Build a canonical template parameter list.
107  TemplateParameterList *Params = TTP->getTemplateParameters();
108  SmallVector<NamedDecl *, 4> CanonParams;
109  CanonParams.reserve(Params->size());
110  for (TemplateParameterList::const_iterator P = Params->begin(),
111                                          PEnd = Params->end();
112       P != PEnd; ++P) {
113    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
114      CanonParams.push_back(
115                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
116                                               SourceLocation(),
117                                               SourceLocation(),
118                                               TTP->getDepth(),
119                                               TTP->getIndex(), 0, false,
120                                               TTP->isParameterPack()));
121    else if (NonTypeTemplateParmDecl *NTTP
122             = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
123      QualType T = getCanonicalType(NTTP->getType());
124      TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
125      NonTypeTemplateParmDecl *Param;
126      if (NTTP->isExpandedParameterPack()) {
127        SmallVector<QualType, 2> ExpandedTypes;
128        SmallVector<TypeSourceInfo *, 2> ExpandedTInfos;
129        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
130          ExpandedTypes.push_back(getCanonicalType(NTTP->getExpansionType(I)));
131          ExpandedTInfos.push_back(
132                                getTrivialTypeSourceInfo(ExpandedTypes.back()));
133        }
134
135        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
136                                                SourceLocation(),
137                                                SourceLocation(),
138                                                NTTP->getDepth(),
139                                                NTTP->getPosition(), 0,
140                                                T,
141                                                TInfo,
142                                                ExpandedTypes.data(),
143                                                ExpandedTypes.size(),
144                                                ExpandedTInfos.data());
145      } else {
146        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
147                                                SourceLocation(),
148                                                SourceLocation(),
149                                                NTTP->getDepth(),
150                                                NTTP->getPosition(), 0,
151                                                T,
152                                                NTTP->isParameterPack(),
153                                                TInfo);
154      }
155      CanonParams.push_back(Param);
156
157    } else
158      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
159                                           cast<TemplateTemplateParmDecl>(*P)));
160  }
161
162  TemplateTemplateParmDecl *CanonTTP
163    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
164                                       SourceLocation(), TTP->getDepth(),
165                                       TTP->getPosition(),
166                                       TTP->isParameterPack(),
167                                       0,
168                         TemplateParameterList::Create(*this, SourceLocation(),
169                                                       SourceLocation(),
170                                                       CanonParams.data(),
171                                                       CanonParams.size(),
172                                                       SourceLocation()));
173
174  // Get the new insert position for the node we care about.
175  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
176  assert(Canonical == 0 && "Shouldn't be in the map!");
177  (void)Canonical;
178
179  // Create the canonical template template parameter entry.
180  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
181  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
182  return CanonTTP;
183}
184
185CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
186  if (!LangOpts.CPlusPlus) return 0;
187
188  switch (T.getCXXABI()) {
189  case CXXABI_ARM:
190    return CreateARMCXXABI(*this);
191  case CXXABI_Itanium:
192    return CreateItaniumCXXABI(*this);
193  case CXXABI_Microsoft:
194    return CreateMicrosoftCXXABI(*this);
195  }
196  return 0;
197}
198
199static const LangAS::Map *getAddressSpaceMap(const TargetInfo &T,
200                                             const LangOptions &LOpts) {
201  if (LOpts.FakeAddressSpaceMap) {
202    // The fake address space map must have a distinct entry for each
203    // language-specific address space.
204    static const unsigned FakeAddrSpaceMap[] = {
205      1, // opencl_global
206      2, // opencl_local
207      3  // opencl_constant
208    };
209    return &FakeAddrSpaceMap;
210  } else {
211    return &T.getAddressSpaceMap();
212  }
213}
214
215ASTContext::ASTContext(LangOptions& LOpts, SourceManager &SM,
216                       const TargetInfo *t,
217                       IdentifierTable &idents, SelectorTable &sels,
218                       Builtin::Context &builtins,
219                       unsigned size_reserve,
220                       bool DelayInitialization)
221  : FunctionProtoTypes(this_()),
222    TemplateSpecializationTypes(this_()),
223    DependentTemplateSpecializationTypes(this_()),
224    SubstTemplateTemplateParmPacks(this_()),
225    GlobalNestedNameSpecifier(0),
226    Int128Decl(0), UInt128Decl(0),
227    ObjCIdDecl(0), ObjCSelDecl(0), ObjCClassDecl(0),
228    CFConstantStringTypeDecl(0), ObjCInstanceTypeDecl(0),
229    FILEDecl(0),
230    jmp_bufDecl(0), sigjmp_bufDecl(0), BlockDescriptorType(0),
231    BlockDescriptorExtendedType(0), cudaConfigureCallDecl(0),
232    NullTypeSourceInfo(QualType()),
233    SourceMgr(SM), LangOpts(LOpts),
234    AddrSpaceMap(0), Target(t), PrintingPolicy(LOpts),
235    Idents(idents), Selectors(sels),
236    BuiltinInfo(builtins),
237    DeclarationNames(*this),
238    ExternalSource(0), Listener(0),
239    LastSDM(0, 0),
240    UniqueBlockByRefTypeID(0)
241{
242  if (size_reserve > 0) Types.reserve(size_reserve);
243  TUDecl = TranslationUnitDecl::Create(*this);
244
245  if (!DelayInitialization) {
246    assert(t && "No target supplied for ASTContext initialization");
247    InitBuiltinTypes(*t);
248  }
249}
250
251ASTContext::~ASTContext() {
252  // Release the DenseMaps associated with DeclContext objects.
253  // FIXME: Is this the ideal solution?
254  ReleaseDeclContextMaps();
255
256  // Call all of the deallocation functions.
257  for (unsigned I = 0, N = Deallocations.size(); I != N; ++I)
258    Deallocations[I].first(Deallocations[I].second);
259
260  // Release all of the memory associated with overridden C++ methods.
261  for (llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::iterator
262         OM = OverriddenMethods.begin(), OMEnd = OverriddenMethods.end();
263       OM != OMEnd; ++OM)
264    OM->second.Destroy();
265
266  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
267  // because they can contain DenseMaps.
268  for (llvm::DenseMap<const ObjCContainerDecl*,
269       const ASTRecordLayout*>::iterator
270       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
271    // Increment in loop to prevent using deallocated memory.
272    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
273      R->Destroy(*this);
274
275  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
276       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
277    // Increment in loop to prevent using deallocated memory.
278    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
279      R->Destroy(*this);
280  }
281
282  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
283                                                    AEnd = DeclAttrs.end();
284       A != AEnd; ++A)
285    A->second->~AttrVec();
286}
287
288void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
289  Deallocations.push_back(std::make_pair(Callback, Data));
290}
291
292void
293ASTContext::setExternalSource(llvm::OwningPtr<ExternalASTSource> &Source) {
294  ExternalSource.reset(Source.take());
295}
296
297void ASTContext::PrintStats() const {
298  llvm::errs() << "\n*** AST Context Stats:\n";
299  llvm::errs() << "  " << Types.size() << " types total.\n";
300
301  unsigned counts[] = {
302#define TYPE(Name, Parent) 0,
303#define ABSTRACT_TYPE(Name, Parent)
304#include "clang/AST/TypeNodes.def"
305    0 // Extra
306  };
307
308  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
309    Type *T = Types[i];
310    counts[(unsigned)T->getTypeClass()]++;
311  }
312
313  unsigned Idx = 0;
314  unsigned TotalBytes = 0;
315#define TYPE(Name, Parent)                                              \
316  if (counts[Idx])                                                      \
317    llvm::errs() << "    " << counts[Idx] << " " << #Name               \
318                 << " types\n";                                         \
319  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
320  ++Idx;
321#define ABSTRACT_TYPE(Name, Parent)
322#include "clang/AST/TypeNodes.def"
323
324  llvm::errs() << "Total bytes = " << TotalBytes << "\n";
325
326  // Implicit special member functions.
327  llvm::errs() << NumImplicitDefaultConstructorsDeclared << "/"
328               << NumImplicitDefaultConstructors
329               << " implicit default constructors created\n";
330  llvm::errs() << NumImplicitCopyConstructorsDeclared << "/"
331               << NumImplicitCopyConstructors
332               << " implicit copy constructors created\n";
333  if (getLangOptions().CPlusPlus)
334    llvm::errs() << NumImplicitMoveConstructorsDeclared << "/"
335                 << NumImplicitMoveConstructors
336                 << " implicit move constructors created\n";
337  llvm::errs() << NumImplicitCopyAssignmentOperatorsDeclared << "/"
338               << NumImplicitCopyAssignmentOperators
339               << " implicit copy assignment operators created\n";
340  if (getLangOptions().CPlusPlus)
341    llvm::errs() << NumImplicitMoveAssignmentOperatorsDeclared << "/"
342                 << NumImplicitMoveAssignmentOperators
343                 << " implicit move assignment operators created\n";
344  llvm::errs() << NumImplicitDestructorsDeclared << "/"
345               << NumImplicitDestructors
346               << " implicit destructors created\n";
347
348  if (ExternalSource.get()) {
349    llvm::errs() << "\n";
350    ExternalSource->PrintStats();
351  }
352
353  BumpAlloc.PrintStats();
354}
355
356TypedefDecl *ASTContext::getInt128Decl() const {
357  if (!Int128Decl) {
358    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(Int128Ty);
359    Int128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
360                                     getTranslationUnitDecl(),
361                                     SourceLocation(),
362                                     SourceLocation(),
363                                     &Idents.get("__int128_t"),
364                                     TInfo);
365  }
366
367  return Int128Decl;
368}
369
370TypedefDecl *ASTContext::getUInt128Decl() const {
371  if (!UInt128Decl) {
372    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(UnsignedInt128Ty);
373    UInt128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
374                                     getTranslationUnitDecl(),
375                                     SourceLocation(),
376                                     SourceLocation(),
377                                     &Idents.get("__uint128_t"),
378                                     TInfo);
379  }
380
381  return UInt128Decl;
382}
383
384void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
385  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
386  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
387  Types.push_back(Ty);
388}
389
390void ASTContext::InitBuiltinTypes(const TargetInfo &Target) {
391  assert((!this->Target || this->Target == &Target) &&
392         "Incorrect target reinitialization");
393  assert(VoidTy.isNull() && "Context reinitialized?");
394
395  this->Target = &Target;
396
397  ABI.reset(createCXXABI(Target));
398  AddrSpaceMap = getAddressSpaceMap(Target, LangOpts);
399
400  // C99 6.2.5p19.
401  InitBuiltinType(VoidTy,              BuiltinType::Void);
402
403  // C99 6.2.5p2.
404  InitBuiltinType(BoolTy,              BuiltinType::Bool);
405  // C99 6.2.5p3.
406  if (LangOpts.CharIsSigned)
407    InitBuiltinType(CharTy,            BuiltinType::Char_S);
408  else
409    InitBuiltinType(CharTy,            BuiltinType::Char_U);
410  // C99 6.2.5p4.
411  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
412  InitBuiltinType(ShortTy,             BuiltinType::Short);
413  InitBuiltinType(IntTy,               BuiltinType::Int);
414  InitBuiltinType(LongTy,              BuiltinType::Long);
415  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
416
417  // C99 6.2.5p6.
418  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
419  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
420  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
421  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
422  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
423
424  // C99 6.2.5p10.
425  InitBuiltinType(FloatTy,             BuiltinType::Float);
426  InitBuiltinType(DoubleTy,            BuiltinType::Double);
427  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
428
429  // GNU extension, 128-bit integers.
430  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
431  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
432
433  if (LangOpts.CPlusPlus) { // C++ 3.9.1p5
434    if (TargetInfo::isTypeSigned(Target.getWCharType()))
435      InitBuiltinType(WCharTy,           BuiltinType::WChar_S);
436    else  // -fshort-wchar makes wchar_t be unsigned.
437      InitBuiltinType(WCharTy,           BuiltinType::WChar_U);
438  } else // C99
439    WCharTy = getFromTargetType(Target.getWCharType());
440
441  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
442    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
443  else // C99
444    Char16Ty = getFromTargetType(Target.getChar16Type());
445
446  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
447    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
448  else // C99
449    Char32Ty = getFromTargetType(Target.getChar32Type());
450
451  // Placeholder type for type-dependent expressions whose type is
452  // completely unknown. No code should ever check a type against
453  // DependentTy and users should never see it; however, it is here to
454  // help diagnose failures to properly check for type-dependent
455  // expressions.
456  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
457
458  // Placeholder type for functions.
459  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
460
461  // Placeholder type for bound members.
462  InitBuiltinType(BoundMemberTy,       BuiltinType::BoundMember);
463
464  // "any" type; useful for debugger-like clients.
465  InitBuiltinType(UnknownAnyTy,        BuiltinType::UnknownAny);
466
467  // C99 6.2.5p11.
468  FloatComplexTy      = getComplexType(FloatTy);
469  DoubleComplexTy     = getComplexType(DoubleTy);
470  LongDoubleComplexTy = getComplexType(LongDoubleTy);
471
472  BuiltinVaListType = QualType();
473
474  // Builtin types for 'id', 'Class', and 'SEL'.
475  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
476  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
477  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
478
479  ObjCConstantStringType = QualType();
480
481  // void * type
482  VoidPtrTy = getPointerType(VoidTy);
483
484  // nullptr type (C++0x 2.14.7)
485  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
486}
487
488DiagnosticsEngine &ASTContext::getDiagnostics() const {
489  return SourceMgr.getDiagnostics();
490}
491
492AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
493  AttrVec *&Result = DeclAttrs[D];
494  if (!Result) {
495    void *Mem = Allocate(sizeof(AttrVec));
496    Result = new (Mem) AttrVec;
497  }
498
499  return *Result;
500}
501
502/// \brief Erase the attributes corresponding to the given declaration.
503void ASTContext::eraseDeclAttrs(const Decl *D) {
504  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
505  if (Pos != DeclAttrs.end()) {
506    Pos->second->~AttrVec();
507    DeclAttrs.erase(Pos);
508  }
509}
510
511MemberSpecializationInfo *
512ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
513  assert(Var->isStaticDataMember() && "Not a static data member");
514  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
515    = InstantiatedFromStaticDataMember.find(Var);
516  if (Pos == InstantiatedFromStaticDataMember.end())
517    return 0;
518
519  return Pos->second;
520}
521
522void
523ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
524                                                TemplateSpecializationKind TSK,
525                                          SourceLocation PointOfInstantiation) {
526  assert(Inst->isStaticDataMember() && "Not a static data member");
527  assert(Tmpl->isStaticDataMember() && "Not a static data member");
528  assert(!InstantiatedFromStaticDataMember[Inst] &&
529         "Already noted what static data member was instantiated from");
530  InstantiatedFromStaticDataMember[Inst]
531    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
532}
533
534FunctionDecl *ASTContext::getClassScopeSpecializationPattern(
535                                                     const FunctionDecl *FD){
536  assert(FD && "Specialization is 0");
537  llvm::DenseMap<const FunctionDecl*, FunctionDecl *>::const_iterator Pos
538    = ClassScopeSpecializationPattern.find(FD);
539  if (Pos == ClassScopeSpecializationPattern.end())
540    return 0;
541
542  return Pos->second;
543}
544
545void ASTContext::setClassScopeSpecializationPattern(FunctionDecl *FD,
546                                        FunctionDecl *Pattern) {
547  assert(FD && "Specialization is 0");
548  assert(Pattern && "Class scope specialization pattern is 0");
549  ClassScopeSpecializationPattern[FD] = Pattern;
550}
551
552NamedDecl *
553ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
554  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
555    = InstantiatedFromUsingDecl.find(UUD);
556  if (Pos == InstantiatedFromUsingDecl.end())
557    return 0;
558
559  return Pos->second;
560}
561
562void
563ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
564  assert((isa<UsingDecl>(Pattern) ||
565          isa<UnresolvedUsingValueDecl>(Pattern) ||
566          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
567         "pattern decl is not a using decl");
568  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
569  InstantiatedFromUsingDecl[Inst] = Pattern;
570}
571
572UsingShadowDecl *
573ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
574  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
575    = InstantiatedFromUsingShadowDecl.find(Inst);
576  if (Pos == InstantiatedFromUsingShadowDecl.end())
577    return 0;
578
579  return Pos->second;
580}
581
582void
583ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
584                                               UsingShadowDecl *Pattern) {
585  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
586  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
587}
588
589FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
590  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
591    = InstantiatedFromUnnamedFieldDecl.find(Field);
592  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
593    return 0;
594
595  return Pos->second;
596}
597
598void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
599                                                     FieldDecl *Tmpl) {
600  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
601  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
602  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
603         "Already noted what unnamed field was instantiated from");
604
605  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
606}
607
608bool ASTContext::ZeroBitfieldFollowsNonBitfield(const FieldDecl *FD,
609                                    const FieldDecl *LastFD) const {
610  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
611          FD->getBitWidthValue(*this) == 0);
612}
613
614bool ASTContext::ZeroBitfieldFollowsBitfield(const FieldDecl *FD,
615                                             const FieldDecl *LastFD) const {
616  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
617          FD->getBitWidthValue(*this) == 0 &&
618          LastFD->getBitWidthValue(*this) != 0);
619}
620
621bool ASTContext::BitfieldFollowsBitfield(const FieldDecl *FD,
622                                         const FieldDecl *LastFD) const {
623  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
624          FD->getBitWidthValue(*this) &&
625          LastFD->getBitWidthValue(*this));
626}
627
628bool ASTContext::NonBitfieldFollowsBitfield(const FieldDecl *FD,
629                                         const FieldDecl *LastFD) const {
630  return (!FD->isBitField() && LastFD && LastFD->isBitField() &&
631          LastFD->getBitWidthValue(*this));
632}
633
634bool ASTContext::BitfieldFollowsNonBitfield(const FieldDecl *FD,
635                                             const FieldDecl *LastFD) const {
636  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
637          FD->getBitWidthValue(*this));
638}
639
640ASTContext::overridden_cxx_method_iterator
641ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
642  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
643    = OverriddenMethods.find(Method);
644  if (Pos == OverriddenMethods.end())
645    return 0;
646
647  return Pos->second.begin();
648}
649
650ASTContext::overridden_cxx_method_iterator
651ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
652  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
653    = OverriddenMethods.find(Method);
654  if (Pos == OverriddenMethods.end())
655    return 0;
656
657  return Pos->second.end();
658}
659
660unsigned
661ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
662  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
663    = OverriddenMethods.find(Method);
664  if (Pos == OverriddenMethods.end())
665    return 0;
666
667  return Pos->second.size();
668}
669
670void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
671                                     const CXXMethodDecl *Overridden) {
672  OverriddenMethods[Method].push_back(Overridden);
673}
674
675//===----------------------------------------------------------------------===//
676//                         Type Sizing and Analysis
677//===----------------------------------------------------------------------===//
678
679/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
680/// scalar floating point type.
681const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
682  const BuiltinType *BT = T->getAs<BuiltinType>();
683  assert(BT && "Not a floating point type!");
684  switch (BT->getKind()) {
685  default: llvm_unreachable("Not a floating point type!");
686  case BuiltinType::Float:      return Target->getFloatFormat();
687  case BuiltinType::Double:     return Target->getDoubleFormat();
688  case BuiltinType::LongDouble: return Target->getLongDoubleFormat();
689  }
690}
691
692/// getDeclAlign - Return a conservative estimate of the alignment of the
693/// specified decl.  Note that bitfields do not have a valid alignment, so
694/// this method will assert on them.
695/// If @p RefAsPointee, references are treated like their underlying type
696/// (for alignof), else they're treated like pointers (for CodeGen).
697CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) const {
698  unsigned Align = Target->getCharWidth();
699
700  bool UseAlignAttrOnly = false;
701  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
702    Align = AlignFromAttr;
703
704    // __attribute__((aligned)) can increase or decrease alignment
705    // *except* on a struct or struct member, where it only increases
706    // alignment unless 'packed' is also specified.
707    //
708    // It is an error for alignas to decrease alignment, so we can
709    // ignore that possibility;  Sema should diagnose it.
710    if (isa<FieldDecl>(D)) {
711      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
712        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
713    } else {
714      UseAlignAttrOnly = true;
715    }
716  }
717  else if (isa<FieldDecl>(D))
718      UseAlignAttrOnly =
719        D->hasAttr<PackedAttr>() ||
720        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
721
722  // If we're using the align attribute only, just ignore everything
723  // else about the declaration and its type.
724  if (UseAlignAttrOnly) {
725    // do nothing
726
727  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
728    QualType T = VD->getType();
729    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
730      if (RefAsPointee)
731        T = RT->getPointeeType();
732      else
733        T = getPointerType(RT->getPointeeType());
734    }
735    if (!T->isIncompleteType() && !T->isFunctionType()) {
736      // Adjust alignments of declarations with array type by the
737      // large-array alignment on the target.
738      unsigned MinWidth = Target->getLargeArrayMinWidth();
739      const ArrayType *arrayType;
740      if (MinWidth && (arrayType = getAsArrayType(T))) {
741        if (isa<VariableArrayType>(arrayType))
742          Align = std::max(Align, Target->getLargeArrayAlign());
743        else if (isa<ConstantArrayType>(arrayType) &&
744                 MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
745          Align = std::max(Align, Target->getLargeArrayAlign());
746
747        // Walk through any array types while we're at it.
748        T = getBaseElementType(arrayType);
749      }
750      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
751    }
752
753    // Fields can be subject to extra alignment constraints, like if
754    // the field is packed, the struct is packed, or the struct has a
755    // a max-field-alignment constraint (#pragma pack).  So calculate
756    // the actual alignment of the field within the struct, and then
757    // (as we're expected to) constrain that by the alignment of the type.
758    if (const FieldDecl *field = dyn_cast<FieldDecl>(VD)) {
759      // So calculate the alignment of the field.
760      const ASTRecordLayout &layout = getASTRecordLayout(field->getParent());
761
762      // Start with the record's overall alignment.
763      unsigned fieldAlign = toBits(layout.getAlignment());
764
765      // Use the GCD of that and the offset within the record.
766      uint64_t offset = layout.getFieldOffset(field->getFieldIndex());
767      if (offset > 0) {
768        // Alignment is always a power of 2, so the GCD will be a power of 2,
769        // which means we get to do this crazy thing instead of Euclid's.
770        uint64_t lowBitOfOffset = offset & (~offset + 1);
771        if (lowBitOfOffset < fieldAlign)
772          fieldAlign = static_cast<unsigned>(lowBitOfOffset);
773      }
774
775      Align = std::min(Align, fieldAlign);
776    }
777  }
778
779  return toCharUnitsFromBits(Align);
780}
781
782std::pair<CharUnits, CharUnits>
783ASTContext::getTypeInfoInChars(const Type *T) const {
784  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
785  return std::make_pair(toCharUnitsFromBits(Info.first),
786                        toCharUnitsFromBits(Info.second));
787}
788
789std::pair<CharUnits, CharUnits>
790ASTContext::getTypeInfoInChars(QualType T) const {
791  return getTypeInfoInChars(T.getTypePtr());
792}
793
794/// getTypeSize - Return the size of the specified type, in bits.  This method
795/// does not work on incomplete types.
796///
797/// FIXME: Pointers into different addr spaces could have different sizes and
798/// alignment requirements: getPointerInfo should take an AddrSpace, this
799/// should take a QualType, &c.
800std::pair<uint64_t, unsigned>
801ASTContext::getTypeInfo(const Type *T) const {
802  uint64_t Width=0;
803  unsigned Align=8;
804  switch (T->getTypeClass()) {
805#define TYPE(Class, Base)
806#define ABSTRACT_TYPE(Class, Base)
807#define NON_CANONICAL_TYPE(Class, Base)
808#define DEPENDENT_TYPE(Class, Base) case Type::Class:
809#include "clang/AST/TypeNodes.def"
810    llvm_unreachable("Should not see dependent types");
811    break;
812
813  case Type::FunctionNoProto:
814  case Type::FunctionProto:
815    // GCC extension: alignof(function) = 32 bits
816    Width = 0;
817    Align = 32;
818    break;
819
820  case Type::IncompleteArray:
821  case Type::VariableArray:
822    Width = 0;
823    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
824    break;
825
826  case Type::ConstantArray: {
827    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
828
829    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
830    Width = EltInfo.first*CAT->getSize().getZExtValue();
831    Align = EltInfo.second;
832    Width = llvm::RoundUpToAlignment(Width, Align);
833    break;
834  }
835  case Type::ExtVector:
836  case Type::Vector: {
837    const VectorType *VT = cast<VectorType>(T);
838    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
839    Width = EltInfo.first*VT->getNumElements();
840    Align = Width;
841    // If the alignment is not a power of 2, round up to the next power of 2.
842    // This happens for non-power-of-2 length vectors.
843    if (Align & (Align-1)) {
844      Align = llvm::NextPowerOf2(Align);
845      Width = llvm::RoundUpToAlignment(Width, Align);
846    }
847    break;
848  }
849
850  case Type::Builtin:
851    switch (cast<BuiltinType>(T)->getKind()) {
852    default: llvm_unreachable("Unknown builtin type!");
853    case BuiltinType::Void:
854      // GCC extension: alignof(void) = 8 bits.
855      Width = 0;
856      Align = 8;
857      break;
858
859    case BuiltinType::Bool:
860      Width = Target->getBoolWidth();
861      Align = Target->getBoolAlign();
862      break;
863    case BuiltinType::Char_S:
864    case BuiltinType::Char_U:
865    case BuiltinType::UChar:
866    case BuiltinType::SChar:
867      Width = Target->getCharWidth();
868      Align = Target->getCharAlign();
869      break;
870    case BuiltinType::WChar_S:
871    case BuiltinType::WChar_U:
872      Width = Target->getWCharWidth();
873      Align = Target->getWCharAlign();
874      break;
875    case BuiltinType::Char16:
876      Width = Target->getChar16Width();
877      Align = Target->getChar16Align();
878      break;
879    case BuiltinType::Char32:
880      Width = Target->getChar32Width();
881      Align = Target->getChar32Align();
882      break;
883    case BuiltinType::UShort:
884    case BuiltinType::Short:
885      Width = Target->getShortWidth();
886      Align = Target->getShortAlign();
887      break;
888    case BuiltinType::UInt:
889    case BuiltinType::Int:
890      Width = Target->getIntWidth();
891      Align = Target->getIntAlign();
892      break;
893    case BuiltinType::ULong:
894    case BuiltinType::Long:
895      Width = Target->getLongWidth();
896      Align = Target->getLongAlign();
897      break;
898    case BuiltinType::ULongLong:
899    case BuiltinType::LongLong:
900      Width = Target->getLongLongWidth();
901      Align = Target->getLongLongAlign();
902      break;
903    case BuiltinType::Int128:
904    case BuiltinType::UInt128:
905      Width = 128;
906      Align = 128; // int128_t is 128-bit aligned on all targets.
907      break;
908    case BuiltinType::Float:
909      Width = Target->getFloatWidth();
910      Align = Target->getFloatAlign();
911      break;
912    case BuiltinType::Double:
913      Width = Target->getDoubleWidth();
914      Align = Target->getDoubleAlign();
915      break;
916    case BuiltinType::LongDouble:
917      Width = Target->getLongDoubleWidth();
918      Align = Target->getLongDoubleAlign();
919      break;
920    case BuiltinType::NullPtr:
921      Width = Target->getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
922      Align = Target->getPointerAlign(0); //   == sizeof(void*)
923      break;
924    case BuiltinType::ObjCId:
925    case BuiltinType::ObjCClass:
926    case BuiltinType::ObjCSel:
927      Width = Target->getPointerWidth(0);
928      Align = Target->getPointerAlign(0);
929      break;
930    }
931    break;
932  case Type::ObjCObjectPointer:
933    Width = Target->getPointerWidth(0);
934    Align = Target->getPointerAlign(0);
935    break;
936  case Type::BlockPointer: {
937    unsigned AS = getTargetAddressSpace(
938        cast<BlockPointerType>(T)->getPointeeType());
939    Width = Target->getPointerWidth(AS);
940    Align = Target->getPointerAlign(AS);
941    break;
942  }
943  case Type::LValueReference:
944  case Type::RValueReference: {
945    // alignof and sizeof should never enter this code path here, so we go
946    // the pointer route.
947    unsigned AS = getTargetAddressSpace(
948        cast<ReferenceType>(T)->getPointeeType());
949    Width = Target->getPointerWidth(AS);
950    Align = Target->getPointerAlign(AS);
951    break;
952  }
953  case Type::Pointer: {
954    unsigned AS = getTargetAddressSpace(cast<PointerType>(T)->getPointeeType());
955    Width = Target->getPointerWidth(AS);
956    Align = Target->getPointerAlign(AS);
957    break;
958  }
959  case Type::MemberPointer: {
960    const MemberPointerType *MPT = cast<MemberPointerType>(T);
961    std::pair<uint64_t, unsigned> PtrDiffInfo =
962      getTypeInfo(getPointerDiffType());
963    Width = PtrDiffInfo.first * ABI->getMemberPointerSize(MPT);
964    Align = PtrDiffInfo.second;
965    break;
966  }
967  case Type::Complex: {
968    // Complex types have the same alignment as their elements, but twice the
969    // size.
970    std::pair<uint64_t, unsigned> EltInfo =
971      getTypeInfo(cast<ComplexType>(T)->getElementType());
972    Width = EltInfo.first*2;
973    Align = EltInfo.second;
974    break;
975  }
976  case Type::ObjCObject:
977    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
978  case Type::ObjCInterface: {
979    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
980    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
981    Width = toBits(Layout.getSize());
982    Align = toBits(Layout.getAlignment());
983    break;
984  }
985  case Type::Record:
986  case Type::Enum: {
987    const TagType *TT = cast<TagType>(T);
988
989    if (TT->getDecl()->isInvalidDecl()) {
990      Width = 8;
991      Align = 8;
992      break;
993    }
994
995    if (const EnumType *ET = dyn_cast<EnumType>(TT))
996      return getTypeInfo(ET->getDecl()->getIntegerType());
997
998    const RecordType *RT = cast<RecordType>(TT);
999    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
1000    Width = toBits(Layout.getSize());
1001    Align = toBits(Layout.getAlignment());
1002    break;
1003  }
1004
1005  case Type::SubstTemplateTypeParm:
1006    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
1007                       getReplacementType().getTypePtr());
1008
1009  case Type::Auto: {
1010    const AutoType *A = cast<AutoType>(T);
1011    assert(A->isDeduced() && "Cannot request the size of a dependent type");
1012    return getTypeInfo(A->getDeducedType().getTypePtr());
1013  }
1014
1015  case Type::Paren:
1016    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
1017
1018  case Type::Typedef: {
1019    const TypedefNameDecl *Typedef = cast<TypedefType>(T)->getDecl();
1020    std::pair<uint64_t, unsigned> Info
1021      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
1022    // If the typedef has an aligned attribute on it, it overrides any computed
1023    // alignment we have.  This violates the GCC documentation (which says that
1024    // attribute(aligned) can only round up) but matches its implementation.
1025    if (unsigned AttrAlign = Typedef->getMaxAlignment())
1026      Align = AttrAlign;
1027    else
1028      Align = Info.second;
1029    Width = Info.first;
1030    break;
1031  }
1032
1033  case Type::TypeOfExpr:
1034    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
1035                         .getTypePtr());
1036
1037  case Type::TypeOf:
1038    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
1039
1040  case Type::Decltype:
1041    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
1042                        .getTypePtr());
1043
1044  case Type::UnaryTransform:
1045    return getTypeInfo(cast<UnaryTransformType>(T)->getUnderlyingType());
1046
1047  case Type::Elaborated:
1048    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
1049
1050  case Type::Attributed:
1051    return getTypeInfo(
1052                  cast<AttributedType>(T)->getEquivalentType().getTypePtr());
1053
1054  case Type::TemplateSpecialization: {
1055    assert(getCanonicalType(T) != T &&
1056           "Cannot request the size of a dependent type");
1057    const TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T);
1058    // A type alias template specialization may refer to a typedef with the
1059    // aligned attribute on it.
1060    if (TST->isTypeAlias())
1061      return getTypeInfo(TST->getAliasedType().getTypePtr());
1062    else
1063      return getTypeInfo(getCanonicalType(T));
1064  }
1065
1066  case Type::Atomic: {
1067    std::pair<uint64_t, unsigned> Info
1068      = getTypeInfo(cast<AtomicType>(T)->getValueType());
1069    Width = Info.first;
1070    Align = Info.second;
1071    if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth() &&
1072        llvm::isPowerOf2_64(Width)) {
1073      // We can potentially perform lock-free atomic operations for this
1074      // type; promote the alignment appropriately.
1075      // FIXME: We could potentially promote the width here as well...
1076      // is that worthwhile?  (Non-struct atomic types generally have
1077      // power-of-two size anyway, but structs might not.  Requires a bit
1078      // of implementation work to make sure we zero out the extra bits.)
1079      Align = static_cast<unsigned>(Width);
1080    }
1081  }
1082
1083  }
1084
1085  assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
1086  return std::make_pair(Width, Align);
1087}
1088
1089/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1090CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1091  return CharUnits::fromQuantity(BitSize / getCharWidth());
1092}
1093
1094/// toBits - Convert a size in characters to a size in characters.
1095int64_t ASTContext::toBits(CharUnits CharSize) const {
1096  return CharSize.getQuantity() * getCharWidth();
1097}
1098
1099/// getTypeSizeInChars - Return the size of the specified type, in characters.
1100/// This method does not work on incomplete types.
1101CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1102  return toCharUnitsFromBits(getTypeSize(T));
1103}
1104CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1105  return toCharUnitsFromBits(getTypeSize(T));
1106}
1107
1108/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1109/// characters. This method does not work on incomplete types.
1110CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1111  return toCharUnitsFromBits(getTypeAlign(T));
1112}
1113CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1114  return toCharUnitsFromBits(getTypeAlign(T));
1115}
1116
1117/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1118/// type for the current target in bits.  This can be different than the ABI
1119/// alignment in cases where it is beneficial for performance to overalign
1120/// a data type.
1121unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1122  unsigned ABIAlign = getTypeAlign(T);
1123
1124  // Double and long long should be naturally aligned if possible.
1125  if (const ComplexType* CT = T->getAs<ComplexType>())
1126    T = CT->getElementType().getTypePtr();
1127  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1128      T->isSpecificBuiltinType(BuiltinType::LongLong))
1129    return std::max(ABIAlign, (unsigned)getTypeSize(T));
1130
1131  return ABIAlign;
1132}
1133
1134/// DeepCollectObjCIvars -
1135/// This routine first collects all declared, but not synthesized, ivars in
1136/// super class and then collects all ivars, including those synthesized for
1137/// current class. This routine is used for implementation of current class
1138/// when all ivars, declared and synthesized are known.
1139///
1140void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1141                                      bool leafClass,
1142                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1143  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1144    DeepCollectObjCIvars(SuperClass, false, Ivars);
1145  if (!leafClass) {
1146    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
1147         E = OI->ivar_end(); I != E; ++I)
1148      Ivars.push_back(*I);
1149  } else {
1150    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1151    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1152         Iv= Iv->getNextIvar())
1153      Ivars.push_back(Iv);
1154  }
1155}
1156
1157/// CollectInheritedProtocols - Collect all protocols in current class and
1158/// those inherited by it.
1159void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1160                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1161  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1162    // We can use protocol_iterator here instead of
1163    // all_referenced_protocol_iterator since we are walking all categories.
1164    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
1165         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
1166      ObjCProtocolDecl *Proto = (*P);
1167      Protocols.insert(Proto);
1168      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1169           PE = Proto->protocol_end(); P != PE; ++P) {
1170        Protocols.insert(*P);
1171        CollectInheritedProtocols(*P, Protocols);
1172      }
1173    }
1174
1175    // Categories of this Interface.
1176    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
1177         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
1178      CollectInheritedProtocols(CDeclChain, Protocols);
1179    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1180      while (SD) {
1181        CollectInheritedProtocols(SD, Protocols);
1182        SD = SD->getSuperClass();
1183      }
1184  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1185    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
1186         PE = OC->protocol_end(); P != PE; ++P) {
1187      ObjCProtocolDecl *Proto = (*P);
1188      Protocols.insert(Proto);
1189      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1190           PE = Proto->protocol_end(); P != PE; ++P)
1191        CollectInheritedProtocols(*P, Protocols);
1192    }
1193  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
1194    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
1195         PE = OP->protocol_end(); P != PE; ++P) {
1196      ObjCProtocolDecl *Proto = (*P);
1197      Protocols.insert(Proto);
1198      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1199           PE = Proto->protocol_end(); P != PE; ++P)
1200        CollectInheritedProtocols(*P, Protocols);
1201    }
1202  }
1203}
1204
1205unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
1206  unsigned count = 0;
1207  // Count ivars declared in class extension.
1208  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
1209       CDecl = CDecl->getNextClassExtension())
1210    count += CDecl->ivar_size();
1211
1212  // Count ivar defined in this class's implementation.  This
1213  // includes synthesized ivars.
1214  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
1215    count += ImplDecl->ivar_size();
1216
1217  return count;
1218}
1219
1220/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
1221ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
1222  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1223    I = ObjCImpls.find(D);
1224  if (I != ObjCImpls.end())
1225    return cast<ObjCImplementationDecl>(I->second);
1226  return 0;
1227}
1228/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
1229ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
1230  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1231    I = ObjCImpls.find(D);
1232  if (I != ObjCImpls.end())
1233    return cast<ObjCCategoryImplDecl>(I->second);
1234  return 0;
1235}
1236
1237/// \brief Set the implementation of ObjCInterfaceDecl.
1238void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1239                           ObjCImplementationDecl *ImplD) {
1240  assert(IFaceD && ImplD && "Passed null params");
1241  ObjCImpls[IFaceD] = ImplD;
1242}
1243/// \brief Set the implementation of ObjCCategoryDecl.
1244void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1245                           ObjCCategoryImplDecl *ImplD) {
1246  assert(CatD && ImplD && "Passed null params");
1247  ObjCImpls[CatD] = ImplD;
1248}
1249
1250/// \brief Get the copy initialization expression of VarDecl,or NULL if
1251/// none exists.
1252Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
1253  assert(VD && "Passed null params");
1254  assert(VD->hasAttr<BlocksAttr>() &&
1255         "getBlockVarCopyInits - not __block var");
1256  llvm::DenseMap<const VarDecl*, Expr*>::iterator
1257    I = BlockVarCopyInits.find(VD);
1258  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : 0;
1259}
1260
1261/// \brief Set the copy inialization expression of a block var decl.
1262void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
1263  assert(VD && Init && "Passed null params");
1264  assert(VD->hasAttr<BlocksAttr>() &&
1265         "setBlockVarCopyInits - not __block var");
1266  BlockVarCopyInits[VD] = Init;
1267}
1268
1269/// \brief Allocate an uninitialized TypeSourceInfo.
1270///
1271/// The caller should initialize the memory held by TypeSourceInfo using
1272/// the TypeLoc wrappers.
1273///
1274/// \param T the type that will be the basis for type source info. This type
1275/// should refer to how the declarator was written in source code, not to
1276/// what type semantic analysis resolved the declarator to.
1277TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1278                                                 unsigned DataSize) const {
1279  if (!DataSize)
1280    DataSize = TypeLoc::getFullDataSizeForType(T);
1281  else
1282    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1283           "incorrect data size provided to CreateTypeSourceInfo!");
1284
1285  TypeSourceInfo *TInfo =
1286    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1287  new (TInfo) TypeSourceInfo(T);
1288  return TInfo;
1289}
1290
1291TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1292                                                     SourceLocation L) const {
1293  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1294  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
1295  return DI;
1296}
1297
1298const ASTRecordLayout &
1299ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
1300  return getObjCLayout(D, 0);
1301}
1302
1303const ASTRecordLayout &
1304ASTContext::getASTObjCImplementationLayout(
1305                                        const ObjCImplementationDecl *D) const {
1306  return getObjCLayout(D->getClassInterface(), D);
1307}
1308
1309//===----------------------------------------------------------------------===//
1310//                   Type creation/memoization methods
1311//===----------------------------------------------------------------------===//
1312
1313QualType
1314ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
1315  unsigned fastQuals = quals.getFastQualifiers();
1316  quals.removeFastQualifiers();
1317
1318  // Check if we've already instantiated this type.
1319  llvm::FoldingSetNodeID ID;
1320  ExtQuals::Profile(ID, baseType, quals);
1321  void *insertPos = 0;
1322  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
1323    assert(eq->getQualifiers() == quals);
1324    return QualType(eq, fastQuals);
1325  }
1326
1327  // If the base type is not canonical, make the appropriate canonical type.
1328  QualType canon;
1329  if (!baseType->isCanonicalUnqualified()) {
1330    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
1331    canonSplit.second.addConsistentQualifiers(quals);
1332    canon = getExtQualType(canonSplit.first, canonSplit.second);
1333
1334    // Re-find the insert position.
1335    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
1336  }
1337
1338  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
1339  ExtQualNodes.InsertNode(eq, insertPos);
1340  return QualType(eq, fastQuals);
1341}
1342
1343QualType
1344ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
1345  QualType CanT = getCanonicalType(T);
1346  if (CanT.getAddressSpace() == AddressSpace)
1347    return T;
1348
1349  // If we are composing extended qualifiers together, merge together
1350  // into one ExtQuals node.
1351  QualifierCollector Quals;
1352  const Type *TypeNode = Quals.strip(T);
1353
1354  // If this type already has an address space specified, it cannot get
1355  // another one.
1356  assert(!Quals.hasAddressSpace() &&
1357         "Type cannot be in multiple addr spaces!");
1358  Quals.addAddressSpace(AddressSpace);
1359
1360  return getExtQualType(TypeNode, Quals);
1361}
1362
1363QualType ASTContext::getObjCGCQualType(QualType T,
1364                                       Qualifiers::GC GCAttr) const {
1365  QualType CanT = getCanonicalType(T);
1366  if (CanT.getObjCGCAttr() == GCAttr)
1367    return T;
1368
1369  if (const PointerType *ptr = T->getAs<PointerType>()) {
1370    QualType Pointee = ptr->getPointeeType();
1371    if (Pointee->isAnyPointerType()) {
1372      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1373      return getPointerType(ResultType);
1374    }
1375  }
1376
1377  // If we are composing extended qualifiers together, merge together
1378  // into one ExtQuals node.
1379  QualifierCollector Quals;
1380  const Type *TypeNode = Quals.strip(T);
1381
1382  // If this type already has an ObjCGC specified, it cannot get
1383  // another one.
1384  assert(!Quals.hasObjCGCAttr() &&
1385         "Type cannot have multiple ObjCGCs!");
1386  Quals.addObjCGCAttr(GCAttr);
1387
1388  return getExtQualType(TypeNode, Quals);
1389}
1390
1391const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
1392                                                   FunctionType::ExtInfo Info) {
1393  if (T->getExtInfo() == Info)
1394    return T;
1395
1396  QualType Result;
1397  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
1398    Result = getFunctionNoProtoType(FNPT->getResultType(), Info);
1399  } else {
1400    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
1401    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
1402    EPI.ExtInfo = Info;
1403    Result = getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1404                             FPT->getNumArgs(), EPI);
1405  }
1406
1407  return cast<FunctionType>(Result.getTypePtr());
1408}
1409
1410/// getComplexType - Return the uniqued reference to the type for a complex
1411/// number with the specified element type.
1412QualType ASTContext::getComplexType(QualType T) const {
1413  // Unique pointers, to guarantee there is only one pointer of a particular
1414  // structure.
1415  llvm::FoldingSetNodeID ID;
1416  ComplexType::Profile(ID, T);
1417
1418  void *InsertPos = 0;
1419  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1420    return QualType(CT, 0);
1421
1422  // If the pointee type isn't canonical, this won't be a canonical type either,
1423  // so fill in the canonical type field.
1424  QualType Canonical;
1425  if (!T.isCanonical()) {
1426    Canonical = getComplexType(getCanonicalType(T));
1427
1428    // Get the new insert position for the node we care about.
1429    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1430    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1431  }
1432  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1433  Types.push_back(New);
1434  ComplexTypes.InsertNode(New, InsertPos);
1435  return QualType(New, 0);
1436}
1437
1438/// getPointerType - Return the uniqued reference to the type for a pointer to
1439/// the specified type.
1440QualType ASTContext::getPointerType(QualType T) const {
1441  // Unique pointers, to guarantee there is only one pointer of a particular
1442  // structure.
1443  llvm::FoldingSetNodeID ID;
1444  PointerType::Profile(ID, T);
1445
1446  void *InsertPos = 0;
1447  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1448    return QualType(PT, 0);
1449
1450  // If the pointee type isn't canonical, this won't be a canonical type either,
1451  // so fill in the canonical type field.
1452  QualType Canonical;
1453  if (!T.isCanonical()) {
1454    Canonical = getPointerType(getCanonicalType(T));
1455
1456    // Get the new insert position for the node we care about.
1457    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1458    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1459  }
1460  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1461  Types.push_back(New);
1462  PointerTypes.InsertNode(New, InsertPos);
1463  return QualType(New, 0);
1464}
1465
1466/// getBlockPointerType - Return the uniqued reference to the type for
1467/// a pointer to the specified block.
1468QualType ASTContext::getBlockPointerType(QualType T) const {
1469  assert(T->isFunctionType() && "block of function types only");
1470  // Unique pointers, to guarantee there is only one block of a particular
1471  // structure.
1472  llvm::FoldingSetNodeID ID;
1473  BlockPointerType::Profile(ID, T);
1474
1475  void *InsertPos = 0;
1476  if (BlockPointerType *PT =
1477        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1478    return QualType(PT, 0);
1479
1480  // If the block pointee type isn't canonical, this won't be a canonical
1481  // type either so fill in the canonical type field.
1482  QualType Canonical;
1483  if (!T.isCanonical()) {
1484    Canonical = getBlockPointerType(getCanonicalType(T));
1485
1486    // Get the new insert position for the node we care about.
1487    BlockPointerType *NewIP =
1488      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1489    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1490  }
1491  BlockPointerType *New
1492    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1493  Types.push_back(New);
1494  BlockPointerTypes.InsertNode(New, InsertPos);
1495  return QualType(New, 0);
1496}
1497
1498/// getLValueReferenceType - Return the uniqued reference to the type for an
1499/// lvalue reference to the specified type.
1500QualType
1501ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
1502  assert(getCanonicalType(T) != OverloadTy &&
1503         "Unresolved overloaded function type");
1504
1505  // Unique pointers, to guarantee there is only one pointer of a particular
1506  // structure.
1507  llvm::FoldingSetNodeID ID;
1508  ReferenceType::Profile(ID, T, SpelledAsLValue);
1509
1510  void *InsertPos = 0;
1511  if (LValueReferenceType *RT =
1512        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1513    return QualType(RT, 0);
1514
1515  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1516
1517  // If the referencee type isn't canonical, this won't be a canonical type
1518  // either, so fill in the canonical type field.
1519  QualType Canonical;
1520  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1521    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1522    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1523
1524    // Get the new insert position for the node we care about.
1525    LValueReferenceType *NewIP =
1526      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1527    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1528  }
1529
1530  LValueReferenceType *New
1531    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1532                                                     SpelledAsLValue);
1533  Types.push_back(New);
1534  LValueReferenceTypes.InsertNode(New, InsertPos);
1535
1536  return QualType(New, 0);
1537}
1538
1539/// getRValueReferenceType - Return the uniqued reference to the type for an
1540/// rvalue reference to the specified type.
1541QualType ASTContext::getRValueReferenceType(QualType T) const {
1542  // Unique pointers, to guarantee there is only one pointer of a particular
1543  // structure.
1544  llvm::FoldingSetNodeID ID;
1545  ReferenceType::Profile(ID, T, false);
1546
1547  void *InsertPos = 0;
1548  if (RValueReferenceType *RT =
1549        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1550    return QualType(RT, 0);
1551
1552  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1553
1554  // If the referencee type isn't canonical, this won't be a canonical type
1555  // either, so fill in the canonical type field.
1556  QualType Canonical;
1557  if (InnerRef || !T.isCanonical()) {
1558    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1559    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1560
1561    // Get the new insert position for the node we care about.
1562    RValueReferenceType *NewIP =
1563      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1564    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1565  }
1566
1567  RValueReferenceType *New
1568    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1569  Types.push_back(New);
1570  RValueReferenceTypes.InsertNode(New, InsertPos);
1571  return QualType(New, 0);
1572}
1573
1574/// getMemberPointerType - Return the uniqued reference to the type for a
1575/// member pointer to the specified type, in the specified class.
1576QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
1577  // Unique pointers, to guarantee there is only one pointer of a particular
1578  // structure.
1579  llvm::FoldingSetNodeID ID;
1580  MemberPointerType::Profile(ID, T, Cls);
1581
1582  void *InsertPos = 0;
1583  if (MemberPointerType *PT =
1584      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1585    return QualType(PT, 0);
1586
1587  // If the pointee or class type isn't canonical, this won't be a canonical
1588  // type either, so fill in the canonical type field.
1589  QualType Canonical;
1590  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1591    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1592
1593    // Get the new insert position for the node we care about.
1594    MemberPointerType *NewIP =
1595      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1596    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1597  }
1598  MemberPointerType *New
1599    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1600  Types.push_back(New);
1601  MemberPointerTypes.InsertNode(New, InsertPos);
1602  return QualType(New, 0);
1603}
1604
1605/// getConstantArrayType - Return the unique reference to the type for an
1606/// array of the specified element type.
1607QualType ASTContext::getConstantArrayType(QualType EltTy,
1608                                          const llvm::APInt &ArySizeIn,
1609                                          ArrayType::ArraySizeModifier ASM,
1610                                          unsigned IndexTypeQuals) const {
1611  assert((EltTy->isDependentType() ||
1612          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1613         "Constant array of VLAs is illegal!");
1614
1615  // Convert the array size into a canonical width matching the pointer size for
1616  // the target.
1617  llvm::APInt ArySize(ArySizeIn);
1618  ArySize =
1619    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
1620
1621  llvm::FoldingSetNodeID ID;
1622  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
1623
1624  void *InsertPos = 0;
1625  if (ConstantArrayType *ATP =
1626      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1627    return QualType(ATP, 0);
1628
1629  // If the element type isn't canonical or has qualifiers, this won't
1630  // be a canonical type either, so fill in the canonical type field.
1631  QualType Canon;
1632  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1633    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1634    Canon = getConstantArrayType(QualType(canonSplit.first, 0), ArySize,
1635                                 ASM, IndexTypeQuals);
1636    Canon = getQualifiedType(Canon, canonSplit.second);
1637
1638    // Get the new insert position for the node we care about.
1639    ConstantArrayType *NewIP =
1640      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1641    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1642  }
1643
1644  ConstantArrayType *New = new(*this,TypeAlignment)
1645    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
1646  ConstantArrayTypes.InsertNode(New, InsertPos);
1647  Types.push_back(New);
1648  return QualType(New, 0);
1649}
1650
1651/// getVariableArrayDecayedType - Turns the given type, which may be
1652/// variably-modified, into the corresponding type with all the known
1653/// sizes replaced with [*].
1654QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
1655  // Vastly most common case.
1656  if (!type->isVariablyModifiedType()) return type;
1657
1658  QualType result;
1659
1660  SplitQualType split = type.getSplitDesugaredType();
1661  const Type *ty = split.first;
1662  switch (ty->getTypeClass()) {
1663#define TYPE(Class, Base)
1664#define ABSTRACT_TYPE(Class, Base)
1665#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
1666#include "clang/AST/TypeNodes.def"
1667    llvm_unreachable("didn't desugar past all non-canonical types?");
1668
1669  // These types should never be variably-modified.
1670  case Type::Builtin:
1671  case Type::Complex:
1672  case Type::Vector:
1673  case Type::ExtVector:
1674  case Type::DependentSizedExtVector:
1675  case Type::ObjCObject:
1676  case Type::ObjCInterface:
1677  case Type::ObjCObjectPointer:
1678  case Type::Record:
1679  case Type::Enum:
1680  case Type::UnresolvedUsing:
1681  case Type::TypeOfExpr:
1682  case Type::TypeOf:
1683  case Type::Decltype:
1684  case Type::UnaryTransform:
1685  case Type::DependentName:
1686  case Type::InjectedClassName:
1687  case Type::TemplateSpecialization:
1688  case Type::DependentTemplateSpecialization:
1689  case Type::TemplateTypeParm:
1690  case Type::SubstTemplateTypeParmPack:
1691  case Type::Auto:
1692  case Type::PackExpansion:
1693    llvm_unreachable("type should never be variably-modified");
1694
1695  // These types can be variably-modified but should never need to
1696  // further decay.
1697  case Type::FunctionNoProto:
1698  case Type::FunctionProto:
1699  case Type::BlockPointer:
1700  case Type::MemberPointer:
1701    return type;
1702
1703  // These types can be variably-modified.  All these modifications
1704  // preserve structure except as noted by comments.
1705  // TODO: if we ever care about optimizing VLAs, there are no-op
1706  // optimizations available here.
1707  case Type::Pointer:
1708    result = getPointerType(getVariableArrayDecayedType(
1709                              cast<PointerType>(ty)->getPointeeType()));
1710    break;
1711
1712  case Type::LValueReference: {
1713    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
1714    result = getLValueReferenceType(
1715                 getVariableArrayDecayedType(lv->getPointeeType()),
1716                                    lv->isSpelledAsLValue());
1717    break;
1718  }
1719
1720  case Type::RValueReference: {
1721    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
1722    result = getRValueReferenceType(
1723                 getVariableArrayDecayedType(lv->getPointeeType()));
1724    break;
1725  }
1726
1727  case Type::Atomic: {
1728    const AtomicType *at = cast<AtomicType>(ty);
1729    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
1730    break;
1731  }
1732
1733  case Type::ConstantArray: {
1734    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
1735    result = getConstantArrayType(
1736                 getVariableArrayDecayedType(cat->getElementType()),
1737                                  cat->getSize(),
1738                                  cat->getSizeModifier(),
1739                                  cat->getIndexTypeCVRQualifiers());
1740    break;
1741  }
1742
1743  case Type::DependentSizedArray: {
1744    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
1745    result = getDependentSizedArrayType(
1746                 getVariableArrayDecayedType(dat->getElementType()),
1747                                        dat->getSizeExpr(),
1748                                        dat->getSizeModifier(),
1749                                        dat->getIndexTypeCVRQualifiers(),
1750                                        dat->getBracketsRange());
1751    break;
1752  }
1753
1754  // Turn incomplete types into [*] types.
1755  case Type::IncompleteArray: {
1756    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
1757    result = getVariableArrayType(
1758                 getVariableArrayDecayedType(iat->getElementType()),
1759                                  /*size*/ 0,
1760                                  ArrayType::Normal,
1761                                  iat->getIndexTypeCVRQualifiers(),
1762                                  SourceRange());
1763    break;
1764  }
1765
1766  // Turn VLA types into [*] types.
1767  case Type::VariableArray: {
1768    const VariableArrayType *vat = cast<VariableArrayType>(ty);
1769    result = getVariableArrayType(
1770                 getVariableArrayDecayedType(vat->getElementType()),
1771                                  /*size*/ 0,
1772                                  ArrayType::Star,
1773                                  vat->getIndexTypeCVRQualifiers(),
1774                                  vat->getBracketsRange());
1775    break;
1776  }
1777  }
1778
1779  // Apply the top-level qualifiers from the original.
1780  return getQualifiedType(result, split.second);
1781}
1782
1783/// getVariableArrayType - Returns a non-unique reference to the type for a
1784/// variable array of the specified element type.
1785QualType ASTContext::getVariableArrayType(QualType EltTy,
1786                                          Expr *NumElts,
1787                                          ArrayType::ArraySizeModifier ASM,
1788                                          unsigned IndexTypeQuals,
1789                                          SourceRange Brackets) const {
1790  // Since we don't unique expressions, it isn't possible to unique VLA's
1791  // that have an expression provided for their size.
1792  QualType Canon;
1793
1794  // Be sure to pull qualifiers off the element type.
1795  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1796    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1797    Canon = getVariableArrayType(QualType(canonSplit.first, 0), NumElts, ASM,
1798                                 IndexTypeQuals, Brackets);
1799    Canon = getQualifiedType(Canon, canonSplit.second);
1800  }
1801
1802  VariableArrayType *New = new(*this, TypeAlignment)
1803    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
1804
1805  VariableArrayTypes.push_back(New);
1806  Types.push_back(New);
1807  return QualType(New, 0);
1808}
1809
1810/// getDependentSizedArrayType - Returns a non-unique reference to
1811/// the type for a dependently-sized array of the specified element
1812/// type.
1813QualType ASTContext::getDependentSizedArrayType(QualType elementType,
1814                                                Expr *numElements,
1815                                                ArrayType::ArraySizeModifier ASM,
1816                                                unsigned elementTypeQuals,
1817                                                SourceRange brackets) const {
1818  assert((!numElements || numElements->isTypeDependent() ||
1819          numElements->isValueDependent()) &&
1820         "Size must be type- or value-dependent!");
1821
1822  // Dependently-sized array types that do not have a specified number
1823  // of elements will have their sizes deduced from a dependent
1824  // initializer.  We do no canonicalization here at all, which is okay
1825  // because they can't be used in most locations.
1826  if (!numElements) {
1827    DependentSizedArrayType *newType
1828      = new (*this, TypeAlignment)
1829          DependentSizedArrayType(*this, elementType, QualType(),
1830                                  numElements, ASM, elementTypeQuals,
1831                                  brackets);
1832    Types.push_back(newType);
1833    return QualType(newType, 0);
1834  }
1835
1836  // Otherwise, we actually build a new type every time, but we
1837  // also build a canonical type.
1838
1839  SplitQualType canonElementType = getCanonicalType(elementType).split();
1840
1841  void *insertPos = 0;
1842  llvm::FoldingSetNodeID ID;
1843  DependentSizedArrayType::Profile(ID, *this,
1844                                   QualType(canonElementType.first, 0),
1845                                   ASM, elementTypeQuals, numElements);
1846
1847  // Look for an existing type with these properties.
1848  DependentSizedArrayType *canonTy =
1849    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1850
1851  // If we don't have one, build one.
1852  if (!canonTy) {
1853    canonTy = new (*this, TypeAlignment)
1854      DependentSizedArrayType(*this, QualType(canonElementType.first, 0),
1855                              QualType(), numElements, ASM, elementTypeQuals,
1856                              brackets);
1857    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
1858    Types.push_back(canonTy);
1859  }
1860
1861  // Apply qualifiers from the element type to the array.
1862  QualType canon = getQualifiedType(QualType(canonTy,0),
1863                                    canonElementType.second);
1864
1865  // If we didn't need extra canonicalization for the element type,
1866  // then just use that as our result.
1867  if (QualType(canonElementType.first, 0) == elementType)
1868    return canon;
1869
1870  // Otherwise, we need to build a type which follows the spelling
1871  // of the element type.
1872  DependentSizedArrayType *sugaredType
1873    = new (*this, TypeAlignment)
1874        DependentSizedArrayType(*this, elementType, canon, numElements,
1875                                ASM, elementTypeQuals, brackets);
1876  Types.push_back(sugaredType);
1877  return QualType(sugaredType, 0);
1878}
1879
1880QualType ASTContext::getIncompleteArrayType(QualType elementType,
1881                                            ArrayType::ArraySizeModifier ASM,
1882                                            unsigned elementTypeQuals) const {
1883  llvm::FoldingSetNodeID ID;
1884  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
1885
1886  void *insertPos = 0;
1887  if (IncompleteArrayType *iat =
1888       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
1889    return QualType(iat, 0);
1890
1891  // If the element type isn't canonical, this won't be a canonical type
1892  // either, so fill in the canonical type field.  We also have to pull
1893  // qualifiers off the element type.
1894  QualType canon;
1895
1896  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
1897    SplitQualType canonSplit = getCanonicalType(elementType).split();
1898    canon = getIncompleteArrayType(QualType(canonSplit.first, 0),
1899                                   ASM, elementTypeQuals);
1900    canon = getQualifiedType(canon, canonSplit.second);
1901
1902    // Get the new insert position for the node we care about.
1903    IncompleteArrayType *existing =
1904      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1905    assert(!existing && "Shouldn't be in the map!"); (void) existing;
1906  }
1907
1908  IncompleteArrayType *newType = new (*this, TypeAlignment)
1909    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
1910
1911  IncompleteArrayTypes.InsertNode(newType, insertPos);
1912  Types.push_back(newType);
1913  return QualType(newType, 0);
1914}
1915
1916/// getVectorType - Return the unique reference to a vector type of
1917/// the specified element type and size. VectorType must be a built-in type.
1918QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1919                                   VectorType::VectorKind VecKind) const {
1920  assert(vecType->isBuiltinType());
1921
1922  // Check if we've already instantiated a vector of this type.
1923  llvm::FoldingSetNodeID ID;
1924  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
1925
1926  void *InsertPos = 0;
1927  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1928    return QualType(VTP, 0);
1929
1930  // If the element type isn't canonical, this won't be a canonical type either,
1931  // so fill in the canonical type field.
1932  QualType Canonical;
1933  if (!vecType.isCanonical()) {
1934    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
1935
1936    // Get the new insert position for the node we care about.
1937    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1938    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1939  }
1940  VectorType *New = new (*this, TypeAlignment)
1941    VectorType(vecType, NumElts, Canonical, VecKind);
1942  VectorTypes.InsertNode(New, InsertPos);
1943  Types.push_back(New);
1944  return QualType(New, 0);
1945}
1946
1947/// getExtVectorType - Return the unique reference to an extended vector type of
1948/// the specified element type and size. VectorType must be a built-in type.
1949QualType
1950ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
1951  assert(vecType->isBuiltinType() || vecType->isDependentType());
1952
1953  // Check if we've already instantiated a vector of this type.
1954  llvm::FoldingSetNodeID ID;
1955  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1956                      VectorType::GenericVector);
1957  void *InsertPos = 0;
1958  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1959    return QualType(VTP, 0);
1960
1961  // If the element type isn't canonical, this won't be a canonical type either,
1962  // so fill in the canonical type field.
1963  QualType Canonical;
1964  if (!vecType.isCanonical()) {
1965    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
1966
1967    // Get the new insert position for the node we care about.
1968    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1969    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1970  }
1971  ExtVectorType *New = new (*this, TypeAlignment)
1972    ExtVectorType(vecType, NumElts, Canonical);
1973  VectorTypes.InsertNode(New, InsertPos);
1974  Types.push_back(New);
1975  return QualType(New, 0);
1976}
1977
1978QualType
1979ASTContext::getDependentSizedExtVectorType(QualType vecType,
1980                                           Expr *SizeExpr,
1981                                           SourceLocation AttrLoc) const {
1982  llvm::FoldingSetNodeID ID;
1983  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
1984                                       SizeExpr);
1985
1986  void *InsertPos = 0;
1987  DependentSizedExtVectorType *Canon
1988    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1989  DependentSizedExtVectorType *New;
1990  if (Canon) {
1991    // We already have a canonical version of this array type; use it as
1992    // the canonical type for a newly-built type.
1993    New = new (*this, TypeAlignment)
1994      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
1995                                  SizeExpr, AttrLoc);
1996  } else {
1997    QualType CanonVecTy = getCanonicalType(vecType);
1998    if (CanonVecTy == vecType) {
1999      New = new (*this, TypeAlignment)
2000        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
2001                                    AttrLoc);
2002
2003      DependentSizedExtVectorType *CanonCheck
2004        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2005      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
2006      (void)CanonCheck;
2007      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
2008    } else {
2009      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
2010                                                      SourceLocation());
2011      New = new (*this, TypeAlignment)
2012        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2013    }
2014  }
2015
2016  Types.push_back(New);
2017  return QualType(New, 0);
2018}
2019
2020/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
2021///
2022QualType
2023ASTContext::getFunctionNoProtoType(QualType ResultTy,
2024                                   const FunctionType::ExtInfo &Info) const {
2025  const CallingConv DefaultCC = Info.getCC();
2026  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2027                               CC_X86StdCall : DefaultCC;
2028  // Unique functions, to guarantee there is only one function of a particular
2029  // structure.
2030  llvm::FoldingSetNodeID ID;
2031  FunctionNoProtoType::Profile(ID, ResultTy, Info);
2032
2033  void *InsertPos = 0;
2034  if (FunctionNoProtoType *FT =
2035        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2036    return QualType(FT, 0);
2037
2038  QualType Canonical;
2039  if (!ResultTy.isCanonical() ||
2040      getCanonicalCallConv(CallConv) != CallConv) {
2041    Canonical =
2042      getFunctionNoProtoType(getCanonicalType(ResultTy),
2043                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
2044
2045    // Get the new insert position for the node we care about.
2046    FunctionNoProtoType *NewIP =
2047      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2048    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2049  }
2050
2051  FunctionProtoType::ExtInfo newInfo = Info.withCallingConv(CallConv);
2052  FunctionNoProtoType *New = new (*this, TypeAlignment)
2053    FunctionNoProtoType(ResultTy, Canonical, newInfo);
2054  Types.push_back(New);
2055  FunctionNoProtoTypes.InsertNode(New, InsertPos);
2056  return QualType(New, 0);
2057}
2058
2059/// getFunctionType - Return a normal function type with a typed argument
2060/// list.  isVariadic indicates whether the argument list includes '...'.
2061QualType
2062ASTContext::getFunctionType(QualType ResultTy,
2063                            const QualType *ArgArray, unsigned NumArgs,
2064                            const FunctionProtoType::ExtProtoInfo &EPI) const {
2065  // Unique functions, to guarantee there is only one function of a particular
2066  // structure.
2067  llvm::FoldingSetNodeID ID;
2068  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, EPI, *this);
2069
2070  void *InsertPos = 0;
2071  if (FunctionProtoType *FTP =
2072        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2073    return QualType(FTP, 0);
2074
2075  // Determine whether the type being created is already canonical or not.
2076  bool isCanonical= EPI.ExceptionSpecType == EST_None && ResultTy.isCanonical();
2077  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
2078    if (!ArgArray[i].isCanonicalAsParam())
2079      isCanonical = false;
2080
2081  const CallingConv DefaultCC = EPI.ExtInfo.getCC();
2082  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2083                               CC_X86StdCall : DefaultCC;
2084
2085  // If this type isn't canonical, get the canonical version of it.
2086  // The exception spec is not part of the canonical type.
2087  QualType Canonical;
2088  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
2089    SmallVector<QualType, 16> CanonicalArgs;
2090    CanonicalArgs.reserve(NumArgs);
2091    for (unsigned i = 0; i != NumArgs; ++i)
2092      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
2093
2094    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
2095    CanonicalEPI.ExceptionSpecType = EST_None;
2096    CanonicalEPI.NumExceptions = 0;
2097    CanonicalEPI.ExtInfo
2098      = CanonicalEPI.ExtInfo.withCallingConv(getCanonicalCallConv(CallConv));
2099
2100    Canonical = getFunctionType(getCanonicalType(ResultTy),
2101                                CanonicalArgs.data(), NumArgs,
2102                                CanonicalEPI);
2103
2104    // Get the new insert position for the node we care about.
2105    FunctionProtoType *NewIP =
2106      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2107    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2108  }
2109
2110  // FunctionProtoType objects are allocated with extra bytes after
2111  // them for three variable size arrays at the end:
2112  //  - parameter types
2113  //  - exception types
2114  //  - consumed-arguments flags
2115  // Instead of the exception types, there could be a noexcept
2116  // expression.
2117  size_t Size = sizeof(FunctionProtoType) +
2118                NumArgs * sizeof(QualType);
2119  if (EPI.ExceptionSpecType == EST_Dynamic)
2120    Size += EPI.NumExceptions * sizeof(QualType);
2121  else if (EPI.ExceptionSpecType == EST_ComputedNoexcept) {
2122    Size += sizeof(Expr*);
2123  }
2124  if (EPI.ConsumedArguments)
2125    Size += NumArgs * sizeof(bool);
2126
2127  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
2128  FunctionProtoType::ExtProtoInfo newEPI = EPI;
2129  newEPI.ExtInfo = EPI.ExtInfo.withCallingConv(CallConv);
2130  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, Canonical, newEPI);
2131  Types.push_back(FTP);
2132  FunctionProtoTypes.InsertNode(FTP, InsertPos);
2133  return QualType(FTP, 0);
2134}
2135
2136#ifndef NDEBUG
2137static bool NeedsInjectedClassNameType(const RecordDecl *D) {
2138  if (!isa<CXXRecordDecl>(D)) return false;
2139  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
2140  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
2141    return true;
2142  if (RD->getDescribedClassTemplate() &&
2143      !isa<ClassTemplateSpecializationDecl>(RD))
2144    return true;
2145  return false;
2146}
2147#endif
2148
2149/// getInjectedClassNameType - Return the unique reference to the
2150/// injected class name type for the specified templated declaration.
2151QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
2152                                              QualType TST) const {
2153  assert(NeedsInjectedClassNameType(Decl));
2154  if (Decl->TypeForDecl) {
2155    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2156  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDeclaration()) {
2157    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
2158    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2159    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2160  } else {
2161    Type *newType =
2162      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
2163    Decl->TypeForDecl = newType;
2164    Types.push_back(newType);
2165  }
2166  return QualType(Decl->TypeForDecl, 0);
2167}
2168
2169/// getTypeDeclType - Return the unique reference to the type for the
2170/// specified type declaration.
2171QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) const {
2172  assert(Decl && "Passed null for Decl param");
2173  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
2174
2175  if (const TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Decl))
2176    return getTypedefType(Typedef);
2177
2178  assert(!isa<TemplateTypeParmDecl>(Decl) &&
2179         "Template type parameter types are always available.");
2180
2181  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
2182    assert(!Record->getPreviousDeclaration() &&
2183           "struct/union has previous declaration");
2184    assert(!NeedsInjectedClassNameType(Record));
2185    return getRecordType(Record);
2186  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
2187    assert(!Enum->getPreviousDeclaration() &&
2188           "enum has previous declaration");
2189    return getEnumType(Enum);
2190  } else if (const UnresolvedUsingTypenameDecl *Using =
2191               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
2192    Type *newType = new (*this, TypeAlignment) UnresolvedUsingType(Using);
2193    Decl->TypeForDecl = newType;
2194    Types.push_back(newType);
2195  } else
2196    llvm_unreachable("TypeDecl without a type?");
2197
2198  return QualType(Decl->TypeForDecl, 0);
2199}
2200
2201/// getTypedefType - Return the unique reference to the type for the
2202/// specified typedef name decl.
2203QualType
2204ASTContext::getTypedefType(const TypedefNameDecl *Decl,
2205                           QualType Canonical) const {
2206  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2207
2208  if (Canonical.isNull())
2209    Canonical = getCanonicalType(Decl->getUnderlyingType());
2210  TypedefType *newType = new(*this, TypeAlignment)
2211    TypedefType(Type::Typedef, Decl, Canonical);
2212  Decl->TypeForDecl = newType;
2213  Types.push_back(newType);
2214  return QualType(newType, 0);
2215}
2216
2217QualType ASTContext::getRecordType(const RecordDecl *Decl) const {
2218  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2219
2220  if (const RecordDecl *PrevDecl = Decl->getPreviousDeclaration())
2221    if (PrevDecl->TypeForDecl)
2222      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2223
2224  RecordType *newType = new (*this, TypeAlignment) RecordType(Decl);
2225  Decl->TypeForDecl = newType;
2226  Types.push_back(newType);
2227  return QualType(newType, 0);
2228}
2229
2230QualType ASTContext::getEnumType(const EnumDecl *Decl) const {
2231  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2232
2233  if (const EnumDecl *PrevDecl = Decl->getPreviousDeclaration())
2234    if (PrevDecl->TypeForDecl)
2235      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2236
2237  EnumType *newType = new (*this, TypeAlignment) EnumType(Decl);
2238  Decl->TypeForDecl = newType;
2239  Types.push_back(newType);
2240  return QualType(newType, 0);
2241}
2242
2243QualType ASTContext::getAttributedType(AttributedType::Kind attrKind,
2244                                       QualType modifiedType,
2245                                       QualType equivalentType) {
2246  llvm::FoldingSetNodeID id;
2247  AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
2248
2249  void *insertPos = 0;
2250  AttributedType *type = AttributedTypes.FindNodeOrInsertPos(id, insertPos);
2251  if (type) return QualType(type, 0);
2252
2253  QualType canon = getCanonicalType(equivalentType);
2254  type = new (*this, TypeAlignment)
2255           AttributedType(canon, attrKind, modifiedType, equivalentType);
2256
2257  Types.push_back(type);
2258  AttributedTypes.InsertNode(type, insertPos);
2259
2260  return QualType(type, 0);
2261}
2262
2263
2264/// \brief Retrieve a substitution-result type.
2265QualType
2266ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
2267                                         QualType Replacement) const {
2268  assert(Replacement.isCanonical()
2269         && "replacement types must always be canonical");
2270
2271  llvm::FoldingSetNodeID ID;
2272  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
2273  void *InsertPos = 0;
2274  SubstTemplateTypeParmType *SubstParm
2275    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2276
2277  if (!SubstParm) {
2278    SubstParm = new (*this, TypeAlignment)
2279      SubstTemplateTypeParmType(Parm, Replacement);
2280    Types.push_back(SubstParm);
2281    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2282  }
2283
2284  return QualType(SubstParm, 0);
2285}
2286
2287/// \brief Retrieve a
2288QualType ASTContext::getSubstTemplateTypeParmPackType(
2289                                          const TemplateTypeParmType *Parm,
2290                                              const TemplateArgument &ArgPack) {
2291#ifndef NDEBUG
2292  for (TemplateArgument::pack_iterator P = ArgPack.pack_begin(),
2293                                    PEnd = ArgPack.pack_end();
2294       P != PEnd; ++P) {
2295    assert(P->getKind() == TemplateArgument::Type &&"Pack contains a non-type");
2296    assert(P->getAsType().isCanonical() && "Pack contains non-canonical type");
2297  }
2298#endif
2299
2300  llvm::FoldingSetNodeID ID;
2301  SubstTemplateTypeParmPackType::Profile(ID, Parm, ArgPack);
2302  void *InsertPos = 0;
2303  if (SubstTemplateTypeParmPackType *SubstParm
2304        = SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos))
2305    return QualType(SubstParm, 0);
2306
2307  QualType Canon;
2308  if (!Parm->isCanonicalUnqualified()) {
2309    Canon = getCanonicalType(QualType(Parm, 0));
2310    Canon = getSubstTemplateTypeParmPackType(cast<TemplateTypeParmType>(Canon),
2311                                             ArgPack);
2312    SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos);
2313  }
2314
2315  SubstTemplateTypeParmPackType *SubstParm
2316    = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
2317                                                               ArgPack);
2318  Types.push_back(SubstParm);
2319  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2320  return QualType(SubstParm, 0);
2321}
2322
2323/// \brief Retrieve the template type parameter type for a template
2324/// parameter or parameter pack with the given depth, index, and (optionally)
2325/// name.
2326QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
2327                                             bool ParameterPack,
2328                                             TemplateTypeParmDecl *TTPDecl) const {
2329  llvm::FoldingSetNodeID ID;
2330  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, TTPDecl);
2331  void *InsertPos = 0;
2332  TemplateTypeParmType *TypeParm
2333    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2334
2335  if (TypeParm)
2336    return QualType(TypeParm, 0);
2337
2338  if (TTPDecl) {
2339    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
2340    TypeParm = new (*this, TypeAlignment) TemplateTypeParmType(TTPDecl, Canon);
2341
2342    TemplateTypeParmType *TypeCheck
2343      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2344    assert(!TypeCheck && "Template type parameter canonical type broken");
2345    (void)TypeCheck;
2346  } else
2347    TypeParm = new (*this, TypeAlignment)
2348      TemplateTypeParmType(Depth, Index, ParameterPack);
2349
2350  Types.push_back(TypeParm);
2351  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
2352
2353  return QualType(TypeParm, 0);
2354}
2355
2356TypeSourceInfo *
2357ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
2358                                              SourceLocation NameLoc,
2359                                        const TemplateArgumentListInfo &Args,
2360                                              QualType Underlying) const {
2361  assert(!Name.getAsDependentTemplateName() &&
2362         "No dependent template names here!");
2363  QualType TST = getTemplateSpecializationType(Name, Args, Underlying);
2364
2365  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
2366  TemplateSpecializationTypeLoc TL
2367    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
2368  TL.setTemplateNameLoc(NameLoc);
2369  TL.setLAngleLoc(Args.getLAngleLoc());
2370  TL.setRAngleLoc(Args.getRAngleLoc());
2371  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
2372    TL.setArgLocInfo(i, Args[i].getLocInfo());
2373  return DI;
2374}
2375
2376QualType
2377ASTContext::getTemplateSpecializationType(TemplateName Template,
2378                                          const TemplateArgumentListInfo &Args,
2379                                          QualType Underlying) const {
2380  assert(!Template.getAsDependentTemplateName() &&
2381         "No dependent template names here!");
2382
2383  unsigned NumArgs = Args.size();
2384
2385  SmallVector<TemplateArgument, 4> ArgVec;
2386  ArgVec.reserve(NumArgs);
2387  for (unsigned i = 0; i != NumArgs; ++i)
2388    ArgVec.push_back(Args[i].getArgument());
2389
2390  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
2391                                       Underlying);
2392}
2393
2394QualType
2395ASTContext::getTemplateSpecializationType(TemplateName Template,
2396                                          const TemplateArgument *Args,
2397                                          unsigned NumArgs,
2398                                          QualType Underlying) const {
2399  assert(!Template.getAsDependentTemplateName() &&
2400         "No dependent template names here!");
2401  // Look through qualified template names.
2402  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2403    Template = TemplateName(QTN->getTemplateDecl());
2404
2405  bool isTypeAlias =
2406    Template.getAsTemplateDecl() &&
2407    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
2408
2409  QualType CanonType;
2410  if (!Underlying.isNull())
2411    CanonType = getCanonicalType(Underlying);
2412  else {
2413    assert(!isTypeAlias &&
2414           "Underlying type for template alias must be computed by caller");
2415    CanonType = getCanonicalTemplateSpecializationType(Template, Args,
2416                                                       NumArgs);
2417  }
2418
2419  // Allocate the (non-canonical) template specialization type, but don't
2420  // try to unique it: these types typically have location information that
2421  // we don't unique and don't want to lose.
2422  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
2423                       sizeof(TemplateArgument) * NumArgs +
2424                       (isTypeAlias ? sizeof(QualType) : 0),
2425                       TypeAlignment);
2426  TemplateSpecializationType *Spec
2427    = new (Mem) TemplateSpecializationType(Template,
2428                                           Args, NumArgs,
2429                                           CanonType,
2430                                         isTypeAlias ? Underlying : QualType());
2431
2432  Types.push_back(Spec);
2433  return QualType(Spec, 0);
2434}
2435
2436QualType
2437ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
2438                                                   const TemplateArgument *Args,
2439                                                   unsigned NumArgs) const {
2440  assert(!Template.getAsDependentTemplateName() &&
2441         "No dependent template names here!");
2442  assert((!Template.getAsTemplateDecl() ||
2443          !isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl())) &&
2444         "Underlying type for template alias must be computed by caller");
2445
2446  // Look through qualified template names.
2447  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2448    Template = TemplateName(QTN->getTemplateDecl());
2449
2450  // Build the canonical template specialization type.
2451  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
2452  SmallVector<TemplateArgument, 4> CanonArgs;
2453  CanonArgs.reserve(NumArgs);
2454  for (unsigned I = 0; I != NumArgs; ++I)
2455    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
2456
2457  // Determine whether this canonical template specialization type already
2458  // exists.
2459  llvm::FoldingSetNodeID ID;
2460  TemplateSpecializationType::Profile(ID, CanonTemplate,
2461                                      CanonArgs.data(), NumArgs, *this);
2462
2463  void *InsertPos = 0;
2464  TemplateSpecializationType *Spec
2465    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2466
2467  if (!Spec) {
2468    // Allocate a new canonical template specialization type.
2469    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2470                          sizeof(TemplateArgument) * NumArgs),
2471                         TypeAlignment);
2472    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
2473                                                CanonArgs.data(), NumArgs,
2474                                                QualType(), QualType());
2475    Types.push_back(Spec);
2476    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
2477  }
2478
2479  assert(Spec->isDependentType() &&
2480         "Non-dependent template-id type must have a canonical type");
2481  return QualType(Spec, 0);
2482}
2483
2484QualType
2485ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
2486                              NestedNameSpecifier *NNS,
2487                              QualType NamedType) const {
2488  llvm::FoldingSetNodeID ID;
2489  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2490
2491  void *InsertPos = 0;
2492  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2493  if (T)
2494    return QualType(T, 0);
2495
2496  QualType Canon = NamedType;
2497  if (!Canon.isCanonical()) {
2498    Canon = getCanonicalType(NamedType);
2499    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2500    assert(!CheckT && "Elaborated canonical type broken");
2501    (void)CheckT;
2502  }
2503
2504  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2505  Types.push_back(T);
2506  ElaboratedTypes.InsertNode(T, InsertPos);
2507  return QualType(T, 0);
2508}
2509
2510QualType
2511ASTContext::getParenType(QualType InnerType) const {
2512  llvm::FoldingSetNodeID ID;
2513  ParenType::Profile(ID, InnerType);
2514
2515  void *InsertPos = 0;
2516  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2517  if (T)
2518    return QualType(T, 0);
2519
2520  QualType Canon = InnerType;
2521  if (!Canon.isCanonical()) {
2522    Canon = getCanonicalType(InnerType);
2523    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2524    assert(!CheckT && "Paren canonical type broken");
2525    (void)CheckT;
2526  }
2527
2528  T = new (*this) ParenType(InnerType, Canon);
2529  Types.push_back(T);
2530  ParenTypes.InsertNode(T, InsertPos);
2531  return QualType(T, 0);
2532}
2533
2534QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2535                                          NestedNameSpecifier *NNS,
2536                                          const IdentifierInfo *Name,
2537                                          QualType Canon) const {
2538  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2539
2540  if (Canon.isNull()) {
2541    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2542    ElaboratedTypeKeyword CanonKeyword = Keyword;
2543    if (Keyword == ETK_None)
2544      CanonKeyword = ETK_Typename;
2545
2546    if (CanonNNS != NNS || CanonKeyword != Keyword)
2547      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2548  }
2549
2550  llvm::FoldingSetNodeID ID;
2551  DependentNameType::Profile(ID, Keyword, NNS, Name);
2552
2553  void *InsertPos = 0;
2554  DependentNameType *T
2555    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2556  if (T)
2557    return QualType(T, 0);
2558
2559  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2560  Types.push_back(T);
2561  DependentNameTypes.InsertNode(T, InsertPos);
2562  return QualType(T, 0);
2563}
2564
2565QualType
2566ASTContext::getDependentTemplateSpecializationType(
2567                                 ElaboratedTypeKeyword Keyword,
2568                                 NestedNameSpecifier *NNS,
2569                                 const IdentifierInfo *Name,
2570                                 const TemplateArgumentListInfo &Args) const {
2571  // TODO: avoid this copy
2572  SmallVector<TemplateArgument, 16> ArgCopy;
2573  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2574    ArgCopy.push_back(Args[I].getArgument());
2575  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2576                                                ArgCopy.size(),
2577                                                ArgCopy.data());
2578}
2579
2580QualType
2581ASTContext::getDependentTemplateSpecializationType(
2582                                 ElaboratedTypeKeyword Keyword,
2583                                 NestedNameSpecifier *NNS,
2584                                 const IdentifierInfo *Name,
2585                                 unsigned NumArgs,
2586                                 const TemplateArgument *Args) const {
2587  assert((!NNS || NNS->isDependent()) &&
2588         "nested-name-specifier must be dependent");
2589
2590  llvm::FoldingSetNodeID ID;
2591  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2592                                               Name, NumArgs, Args);
2593
2594  void *InsertPos = 0;
2595  DependentTemplateSpecializationType *T
2596    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2597  if (T)
2598    return QualType(T, 0);
2599
2600  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2601
2602  ElaboratedTypeKeyword CanonKeyword = Keyword;
2603  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2604
2605  bool AnyNonCanonArgs = false;
2606  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2607  for (unsigned I = 0; I != NumArgs; ++I) {
2608    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2609    if (!CanonArgs[I].structurallyEquals(Args[I]))
2610      AnyNonCanonArgs = true;
2611  }
2612
2613  QualType Canon;
2614  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2615    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2616                                                   Name, NumArgs,
2617                                                   CanonArgs.data());
2618
2619    // Find the insert position again.
2620    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2621  }
2622
2623  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2624                        sizeof(TemplateArgument) * NumArgs),
2625                       TypeAlignment);
2626  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2627                                                    Name, NumArgs, Args, Canon);
2628  Types.push_back(T);
2629  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2630  return QualType(T, 0);
2631}
2632
2633QualType ASTContext::getPackExpansionType(QualType Pattern,
2634                                      llvm::Optional<unsigned> NumExpansions) {
2635  llvm::FoldingSetNodeID ID;
2636  PackExpansionType::Profile(ID, Pattern, NumExpansions);
2637
2638  assert(Pattern->containsUnexpandedParameterPack() &&
2639         "Pack expansions must expand one or more parameter packs");
2640  void *InsertPos = 0;
2641  PackExpansionType *T
2642    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2643  if (T)
2644    return QualType(T, 0);
2645
2646  QualType Canon;
2647  if (!Pattern.isCanonical()) {
2648    Canon = getPackExpansionType(getCanonicalType(Pattern), NumExpansions);
2649
2650    // Find the insert position again.
2651    PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2652  }
2653
2654  T = new (*this) PackExpansionType(Pattern, Canon, NumExpansions);
2655  Types.push_back(T);
2656  PackExpansionTypes.InsertNode(T, InsertPos);
2657  return QualType(T, 0);
2658}
2659
2660/// CmpProtocolNames - Comparison predicate for sorting protocols
2661/// alphabetically.
2662static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2663                            const ObjCProtocolDecl *RHS) {
2664  return LHS->getDeclName() < RHS->getDeclName();
2665}
2666
2667static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2668                                unsigned NumProtocols) {
2669  if (NumProtocols == 0) return true;
2670
2671  for (unsigned i = 1; i != NumProtocols; ++i)
2672    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]))
2673      return false;
2674  return true;
2675}
2676
2677static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2678                                   unsigned &NumProtocols) {
2679  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2680
2681  // Sort protocols, keyed by name.
2682  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2683
2684  // Remove duplicates.
2685  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2686  NumProtocols = ProtocolsEnd-Protocols;
2687}
2688
2689QualType ASTContext::getObjCObjectType(QualType BaseType,
2690                                       ObjCProtocolDecl * const *Protocols,
2691                                       unsigned NumProtocols) const {
2692  // If the base type is an interface and there aren't any protocols
2693  // to add, then the interface type will do just fine.
2694  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2695    return BaseType;
2696
2697  // Look in the folding set for an existing type.
2698  llvm::FoldingSetNodeID ID;
2699  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2700  void *InsertPos = 0;
2701  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2702    return QualType(QT, 0);
2703
2704  // Build the canonical type, which has the canonical base type and
2705  // a sorted-and-uniqued list of protocols.
2706  QualType Canonical;
2707  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2708  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2709    if (!ProtocolsSorted) {
2710      SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2711                                                     Protocols + NumProtocols);
2712      unsigned UniqueCount = NumProtocols;
2713
2714      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2715      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2716                                    &Sorted[0], UniqueCount);
2717    } else {
2718      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2719                                    Protocols, NumProtocols);
2720    }
2721
2722    // Regenerate InsertPos.
2723    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2724  }
2725
2726  unsigned Size = sizeof(ObjCObjectTypeImpl);
2727  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2728  void *Mem = Allocate(Size, TypeAlignment);
2729  ObjCObjectTypeImpl *T =
2730    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2731
2732  Types.push_back(T);
2733  ObjCObjectTypes.InsertNode(T, InsertPos);
2734  return QualType(T, 0);
2735}
2736
2737/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2738/// the given object type.
2739QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
2740  llvm::FoldingSetNodeID ID;
2741  ObjCObjectPointerType::Profile(ID, ObjectT);
2742
2743  void *InsertPos = 0;
2744  if (ObjCObjectPointerType *QT =
2745              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2746    return QualType(QT, 0);
2747
2748  // Find the canonical object type.
2749  QualType Canonical;
2750  if (!ObjectT.isCanonical()) {
2751    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2752
2753    // Regenerate InsertPos.
2754    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2755  }
2756
2757  // No match.
2758  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2759  ObjCObjectPointerType *QType =
2760    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2761
2762  Types.push_back(QType);
2763  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2764  return QualType(QType, 0);
2765}
2766
2767/// getObjCInterfaceType - Return the unique reference to the type for the
2768/// specified ObjC interface decl. The list of protocols is optional.
2769QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl) const {
2770  if (Decl->TypeForDecl)
2771    return QualType(Decl->TypeForDecl, 0);
2772
2773  // FIXME: redeclarations?
2774  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2775  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2776  Decl->TypeForDecl = T;
2777  Types.push_back(T);
2778  return QualType(T, 0);
2779}
2780
2781/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2782/// TypeOfExprType AST's (since expression's are never shared). For example,
2783/// multiple declarations that refer to "typeof(x)" all contain different
2784/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2785/// on canonical type's (which are always unique).
2786QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
2787  TypeOfExprType *toe;
2788  if (tofExpr->isTypeDependent()) {
2789    llvm::FoldingSetNodeID ID;
2790    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2791
2792    void *InsertPos = 0;
2793    DependentTypeOfExprType *Canon
2794      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2795    if (Canon) {
2796      // We already have a "canonical" version of an identical, dependent
2797      // typeof(expr) type. Use that as our canonical type.
2798      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2799                                          QualType((TypeOfExprType*)Canon, 0));
2800    } else {
2801      // Build a new, canonical typeof(expr) type.
2802      Canon
2803        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2804      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2805      toe = Canon;
2806    }
2807  } else {
2808    QualType Canonical = getCanonicalType(tofExpr->getType());
2809    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2810  }
2811  Types.push_back(toe);
2812  return QualType(toe, 0);
2813}
2814
2815/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2816/// TypeOfType AST's. The only motivation to unique these nodes would be
2817/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2818/// an issue. This doesn't effect the type checker, since it operates
2819/// on canonical type's (which are always unique).
2820QualType ASTContext::getTypeOfType(QualType tofType) const {
2821  QualType Canonical = getCanonicalType(tofType);
2822  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2823  Types.push_back(tot);
2824  return QualType(tot, 0);
2825}
2826
2827/// getDecltypeForExpr - Given an expr, will return the decltype for that
2828/// expression, according to the rules in C++0x [dcl.type.simple]p4
2829static QualType getDecltypeForExpr(const Expr *e, const ASTContext &Context) {
2830  if (e->isTypeDependent())
2831    return Context.DependentTy;
2832
2833  // If e is an id expression or a class member access, decltype(e) is defined
2834  // as the type of the entity named by e.
2835  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2836    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2837      return VD->getType();
2838  }
2839  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2840    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2841      return FD->getType();
2842  }
2843  // If e is a function call or an invocation of an overloaded operator,
2844  // (parentheses around e are ignored), decltype(e) is defined as the
2845  // return type of that function.
2846  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2847    return CE->getCallReturnType();
2848
2849  QualType T = e->getType();
2850
2851  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2852  // defined as T&, otherwise decltype(e) is defined as T.
2853  if (e->isLValue())
2854    T = Context.getLValueReferenceType(T);
2855
2856  return T;
2857}
2858
2859/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2860/// DecltypeType AST's. The only motivation to unique these nodes would be
2861/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2862/// an issue. This doesn't effect the type checker, since it operates
2863/// on canonical type's (which are always unique).
2864QualType ASTContext::getDecltypeType(Expr *e) const {
2865  DecltypeType *dt;
2866
2867  // C++0x [temp.type]p2:
2868  //   If an expression e involves a template parameter, decltype(e) denotes a
2869  //   unique dependent type. Two such decltype-specifiers refer to the same
2870  //   type only if their expressions are equivalent (14.5.6.1).
2871  if (e->isInstantiationDependent()) {
2872    llvm::FoldingSetNodeID ID;
2873    DependentDecltypeType::Profile(ID, *this, e);
2874
2875    void *InsertPos = 0;
2876    DependentDecltypeType *Canon
2877      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2878    if (Canon) {
2879      // We already have a "canonical" version of an equivalent, dependent
2880      // decltype type. Use that as our canonical type.
2881      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2882                                       QualType((DecltypeType*)Canon, 0));
2883    } else {
2884      // Build a new, canonical typeof(expr) type.
2885      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2886      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2887      dt = Canon;
2888    }
2889  } else {
2890    QualType T = getDecltypeForExpr(e, *this);
2891    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2892  }
2893  Types.push_back(dt);
2894  return QualType(dt, 0);
2895}
2896
2897/// getUnaryTransformationType - We don't unique these, since the memory
2898/// savings are minimal and these are rare.
2899QualType ASTContext::getUnaryTransformType(QualType BaseType,
2900                                           QualType UnderlyingType,
2901                                           UnaryTransformType::UTTKind Kind)
2902    const {
2903  UnaryTransformType *Ty =
2904    new (*this, TypeAlignment) UnaryTransformType (BaseType, UnderlyingType,
2905                                                   Kind,
2906                                 UnderlyingType->isDependentType() ?
2907                                    QualType() : UnderlyingType);
2908  Types.push_back(Ty);
2909  return QualType(Ty, 0);
2910}
2911
2912/// getAutoType - We only unique auto types after they've been deduced.
2913QualType ASTContext::getAutoType(QualType DeducedType) const {
2914  void *InsertPos = 0;
2915  if (!DeducedType.isNull()) {
2916    // Look in the folding set for an existing type.
2917    llvm::FoldingSetNodeID ID;
2918    AutoType::Profile(ID, DeducedType);
2919    if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
2920      return QualType(AT, 0);
2921  }
2922
2923  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType);
2924  Types.push_back(AT);
2925  if (InsertPos)
2926    AutoTypes.InsertNode(AT, InsertPos);
2927  return QualType(AT, 0);
2928}
2929
2930/// getAtomicType - Return the uniqued reference to the atomic type for
2931/// the given value type.
2932QualType ASTContext::getAtomicType(QualType T) const {
2933  // Unique pointers, to guarantee there is only one pointer of a particular
2934  // structure.
2935  llvm::FoldingSetNodeID ID;
2936  AtomicType::Profile(ID, T);
2937
2938  void *InsertPos = 0;
2939  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
2940    return QualType(AT, 0);
2941
2942  // If the atomic value type isn't canonical, this won't be a canonical type
2943  // either, so fill in the canonical type field.
2944  QualType Canonical;
2945  if (!T.isCanonical()) {
2946    Canonical = getAtomicType(getCanonicalType(T));
2947
2948    // Get the new insert position for the node we care about.
2949    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
2950    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2951  }
2952  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
2953  Types.push_back(New);
2954  AtomicTypes.InsertNode(New, InsertPos);
2955  return QualType(New, 0);
2956}
2957
2958/// getAutoDeductType - Get type pattern for deducing against 'auto'.
2959QualType ASTContext::getAutoDeductType() const {
2960  if (AutoDeductTy.isNull())
2961    AutoDeductTy = getAutoType(QualType());
2962  assert(!AutoDeductTy.isNull() && "can't build 'auto' pattern");
2963  return AutoDeductTy;
2964}
2965
2966/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
2967QualType ASTContext::getAutoRRefDeductType() const {
2968  if (AutoRRefDeductTy.isNull())
2969    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
2970  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
2971  return AutoRRefDeductTy;
2972}
2973
2974/// getTagDeclType - Return the unique reference to the type for the
2975/// specified TagDecl (struct/union/class/enum) decl.
2976QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
2977  assert (Decl);
2978  // FIXME: What is the design on getTagDeclType when it requires casting
2979  // away const?  mutable?
2980  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2981}
2982
2983/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2984/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2985/// needs to agree with the definition in <stddef.h>.
2986CanQualType ASTContext::getSizeType() const {
2987  return getFromTargetType(Target->getSizeType());
2988}
2989
2990/// getSignedWCharType - Return the type of "signed wchar_t".
2991/// Used when in C++, as a GCC extension.
2992QualType ASTContext::getSignedWCharType() const {
2993  // FIXME: derive from "Target" ?
2994  return WCharTy;
2995}
2996
2997/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
2998/// Used when in C++, as a GCC extension.
2999QualType ASTContext::getUnsignedWCharType() const {
3000  // FIXME: derive from "Target" ?
3001  return UnsignedIntTy;
3002}
3003
3004/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
3005/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
3006QualType ASTContext::getPointerDiffType() const {
3007  return getFromTargetType(Target->getPtrDiffType(0));
3008}
3009
3010//===----------------------------------------------------------------------===//
3011//                              Type Operators
3012//===----------------------------------------------------------------------===//
3013
3014CanQualType ASTContext::getCanonicalParamType(QualType T) const {
3015  // Push qualifiers into arrays, and then discard any remaining
3016  // qualifiers.
3017  T = getCanonicalType(T);
3018  T = getVariableArrayDecayedType(T);
3019  const Type *Ty = T.getTypePtr();
3020  QualType Result;
3021  if (isa<ArrayType>(Ty)) {
3022    Result = getArrayDecayedType(QualType(Ty,0));
3023  } else if (isa<FunctionType>(Ty)) {
3024    Result = getPointerType(QualType(Ty, 0));
3025  } else {
3026    Result = QualType(Ty, 0);
3027  }
3028
3029  return CanQualType::CreateUnsafe(Result);
3030}
3031
3032QualType ASTContext::getUnqualifiedArrayType(QualType type,
3033                                             Qualifiers &quals) {
3034  SplitQualType splitType = type.getSplitUnqualifiedType();
3035
3036  // FIXME: getSplitUnqualifiedType() actually walks all the way to
3037  // the unqualified desugared type and then drops it on the floor.
3038  // We then have to strip that sugar back off with
3039  // getUnqualifiedDesugaredType(), which is silly.
3040  const ArrayType *AT =
3041    dyn_cast<ArrayType>(splitType.first->getUnqualifiedDesugaredType());
3042
3043  // If we don't have an array, just use the results in splitType.
3044  if (!AT) {
3045    quals = splitType.second;
3046    return QualType(splitType.first, 0);
3047  }
3048
3049  // Otherwise, recurse on the array's element type.
3050  QualType elementType = AT->getElementType();
3051  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
3052
3053  // If that didn't change the element type, AT has no qualifiers, so we
3054  // can just use the results in splitType.
3055  if (elementType == unqualElementType) {
3056    assert(quals.empty()); // from the recursive call
3057    quals = splitType.second;
3058    return QualType(splitType.first, 0);
3059  }
3060
3061  // Otherwise, add in the qualifiers from the outermost type, then
3062  // build the type back up.
3063  quals.addConsistentQualifiers(splitType.second);
3064
3065  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
3066    return getConstantArrayType(unqualElementType, CAT->getSize(),
3067                                CAT->getSizeModifier(), 0);
3068  }
3069
3070  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
3071    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
3072  }
3073
3074  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
3075    return getVariableArrayType(unqualElementType,
3076                                VAT->getSizeExpr(),
3077                                VAT->getSizeModifier(),
3078                                VAT->getIndexTypeCVRQualifiers(),
3079                                VAT->getBracketsRange());
3080  }
3081
3082  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
3083  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
3084                                    DSAT->getSizeModifier(), 0,
3085                                    SourceRange());
3086}
3087
3088/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
3089/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
3090/// they point to and return true. If T1 and T2 aren't pointer types
3091/// or pointer-to-member types, or if they are not similar at this
3092/// level, returns false and leaves T1 and T2 unchanged. Top-level
3093/// qualifiers on T1 and T2 are ignored. This function will typically
3094/// be called in a loop that successively "unwraps" pointer and
3095/// pointer-to-member types to compare them at each level.
3096bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
3097  const PointerType *T1PtrType = T1->getAs<PointerType>(),
3098                    *T2PtrType = T2->getAs<PointerType>();
3099  if (T1PtrType && T2PtrType) {
3100    T1 = T1PtrType->getPointeeType();
3101    T2 = T2PtrType->getPointeeType();
3102    return true;
3103  }
3104
3105  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
3106                          *T2MPType = T2->getAs<MemberPointerType>();
3107  if (T1MPType && T2MPType &&
3108      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
3109                             QualType(T2MPType->getClass(), 0))) {
3110    T1 = T1MPType->getPointeeType();
3111    T2 = T2MPType->getPointeeType();
3112    return true;
3113  }
3114
3115  if (getLangOptions().ObjC1) {
3116    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
3117                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
3118    if (T1OPType && T2OPType) {
3119      T1 = T1OPType->getPointeeType();
3120      T2 = T2OPType->getPointeeType();
3121      return true;
3122    }
3123  }
3124
3125  // FIXME: Block pointers, too?
3126
3127  return false;
3128}
3129
3130DeclarationNameInfo
3131ASTContext::getNameForTemplate(TemplateName Name,
3132                               SourceLocation NameLoc) const {
3133  switch (Name.getKind()) {
3134  case TemplateName::QualifiedTemplate:
3135  case TemplateName::Template:
3136    // DNInfo work in progress: CHECKME: what about DNLoc?
3137    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
3138                               NameLoc);
3139
3140  case TemplateName::OverloadedTemplate: {
3141    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
3142    // DNInfo work in progress: CHECKME: what about DNLoc?
3143    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
3144  }
3145
3146  case TemplateName::DependentTemplate: {
3147    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3148    DeclarationName DName;
3149    if (DTN->isIdentifier()) {
3150      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
3151      return DeclarationNameInfo(DName, NameLoc);
3152    } else {
3153      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
3154      // DNInfo work in progress: FIXME: source locations?
3155      DeclarationNameLoc DNLoc;
3156      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
3157      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
3158      return DeclarationNameInfo(DName, NameLoc, DNLoc);
3159    }
3160  }
3161
3162  case TemplateName::SubstTemplateTemplateParm: {
3163    SubstTemplateTemplateParmStorage *subst
3164      = Name.getAsSubstTemplateTemplateParm();
3165    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
3166                               NameLoc);
3167  }
3168
3169  case TemplateName::SubstTemplateTemplateParmPack: {
3170    SubstTemplateTemplateParmPackStorage *subst
3171      = Name.getAsSubstTemplateTemplateParmPack();
3172    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
3173                               NameLoc);
3174  }
3175  }
3176
3177  llvm_unreachable("bad template name kind!");
3178}
3179
3180TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
3181  switch (Name.getKind()) {
3182  case TemplateName::QualifiedTemplate:
3183  case TemplateName::Template: {
3184    TemplateDecl *Template = Name.getAsTemplateDecl();
3185    if (TemplateTemplateParmDecl *TTP
3186          = dyn_cast<TemplateTemplateParmDecl>(Template))
3187      Template = getCanonicalTemplateTemplateParmDecl(TTP);
3188
3189    // The canonical template name is the canonical template declaration.
3190    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
3191  }
3192
3193  case TemplateName::OverloadedTemplate:
3194    llvm_unreachable("cannot canonicalize overloaded template");
3195
3196  case TemplateName::DependentTemplate: {
3197    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3198    assert(DTN && "Non-dependent template names must refer to template decls.");
3199    return DTN->CanonicalTemplateName;
3200  }
3201
3202  case TemplateName::SubstTemplateTemplateParm: {
3203    SubstTemplateTemplateParmStorage *subst
3204      = Name.getAsSubstTemplateTemplateParm();
3205    return getCanonicalTemplateName(subst->getReplacement());
3206  }
3207
3208  case TemplateName::SubstTemplateTemplateParmPack: {
3209    SubstTemplateTemplateParmPackStorage *subst
3210                                  = Name.getAsSubstTemplateTemplateParmPack();
3211    TemplateTemplateParmDecl *canonParameter
3212      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
3213    TemplateArgument canonArgPack
3214      = getCanonicalTemplateArgument(subst->getArgumentPack());
3215    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
3216  }
3217  }
3218
3219  llvm_unreachable("bad template name!");
3220}
3221
3222bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
3223  X = getCanonicalTemplateName(X);
3224  Y = getCanonicalTemplateName(Y);
3225  return X.getAsVoidPointer() == Y.getAsVoidPointer();
3226}
3227
3228TemplateArgument
3229ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
3230  switch (Arg.getKind()) {
3231    case TemplateArgument::Null:
3232      return Arg;
3233
3234    case TemplateArgument::Expression:
3235      return Arg;
3236
3237    case TemplateArgument::Declaration:
3238      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
3239
3240    case TemplateArgument::Template:
3241      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
3242
3243    case TemplateArgument::TemplateExpansion:
3244      return TemplateArgument(getCanonicalTemplateName(
3245                                         Arg.getAsTemplateOrTemplatePattern()),
3246                              Arg.getNumTemplateExpansions());
3247
3248    case TemplateArgument::Integral:
3249      return TemplateArgument(*Arg.getAsIntegral(),
3250                              getCanonicalType(Arg.getIntegralType()));
3251
3252    case TemplateArgument::Type:
3253      return TemplateArgument(getCanonicalType(Arg.getAsType()));
3254
3255    case TemplateArgument::Pack: {
3256      if (Arg.pack_size() == 0)
3257        return Arg;
3258
3259      TemplateArgument *CanonArgs
3260        = new (*this) TemplateArgument[Arg.pack_size()];
3261      unsigned Idx = 0;
3262      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
3263                                        AEnd = Arg.pack_end();
3264           A != AEnd; (void)++A, ++Idx)
3265        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
3266
3267      return TemplateArgument(CanonArgs, Arg.pack_size());
3268    }
3269  }
3270
3271  // Silence GCC warning
3272  llvm_unreachable("Unhandled template argument kind");
3273}
3274
3275NestedNameSpecifier *
3276ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
3277  if (!NNS)
3278    return 0;
3279
3280  switch (NNS->getKind()) {
3281  case NestedNameSpecifier::Identifier:
3282    // Canonicalize the prefix but keep the identifier the same.
3283    return NestedNameSpecifier::Create(*this,
3284                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
3285                                       NNS->getAsIdentifier());
3286
3287  case NestedNameSpecifier::Namespace:
3288    // A namespace is canonical; build a nested-name-specifier with
3289    // this namespace and no prefix.
3290    return NestedNameSpecifier::Create(*this, 0,
3291                                 NNS->getAsNamespace()->getOriginalNamespace());
3292
3293  case NestedNameSpecifier::NamespaceAlias:
3294    // A namespace is canonical; build a nested-name-specifier with
3295    // this namespace and no prefix.
3296    return NestedNameSpecifier::Create(*this, 0,
3297                                    NNS->getAsNamespaceAlias()->getNamespace()
3298                                                      ->getOriginalNamespace());
3299
3300  case NestedNameSpecifier::TypeSpec:
3301  case NestedNameSpecifier::TypeSpecWithTemplate: {
3302    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
3303
3304    // If we have some kind of dependent-named type (e.g., "typename T::type"),
3305    // break it apart into its prefix and identifier, then reconsititute those
3306    // as the canonical nested-name-specifier. This is required to canonicalize
3307    // a dependent nested-name-specifier involving typedefs of dependent-name
3308    // types, e.g.,
3309    //   typedef typename T::type T1;
3310    //   typedef typename T1::type T2;
3311    if (const DependentNameType *DNT = T->getAs<DependentNameType>()) {
3312      NestedNameSpecifier *Prefix
3313        = getCanonicalNestedNameSpecifier(DNT->getQualifier());
3314      return NestedNameSpecifier::Create(*this, Prefix,
3315                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
3316    }
3317
3318    // Do the same thing as above, but with dependent-named specializations.
3319    if (const DependentTemplateSpecializationType *DTST
3320          = T->getAs<DependentTemplateSpecializationType>()) {
3321      NestedNameSpecifier *Prefix
3322        = getCanonicalNestedNameSpecifier(DTST->getQualifier());
3323
3324      T = getDependentTemplateSpecializationType(DTST->getKeyword(),
3325                                                 Prefix, DTST->getIdentifier(),
3326                                                 DTST->getNumArgs(),
3327                                                 DTST->getArgs());
3328      T = getCanonicalType(T);
3329    }
3330
3331    return NestedNameSpecifier::Create(*this, 0, false,
3332                                       const_cast<Type*>(T.getTypePtr()));
3333  }
3334
3335  case NestedNameSpecifier::Global:
3336    // The global specifier is canonical and unique.
3337    return NNS;
3338  }
3339
3340  // Required to silence a GCC warning
3341  return 0;
3342}
3343
3344
3345const ArrayType *ASTContext::getAsArrayType(QualType T) const {
3346  // Handle the non-qualified case efficiently.
3347  if (!T.hasLocalQualifiers()) {
3348    // Handle the common positive case fast.
3349    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
3350      return AT;
3351  }
3352
3353  // Handle the common negative case fast.
3354  if (!isa<ArrayType>(T.getCanonicalType()))
3355    return 0;
3356
3357  // Apply any qualifiers from the array type to the element type.  This
3358  // implements C99 6.7.3p8: "If the specification of an array type includes
3359  // any type qualifiers, the element type is so qualified, not the array type."
3360
3361  // If we get here, we either have type qualifiers on the type, or we have
3362  // sugar such as a typedef in the way.  If we have type qualifiers on the type
3363  // we must propagate them down into the element type.
3364
3365  SplitQualType split = T.getSplitDesugaredType();
3366  Qualifiers qs = split.second;
3367
3368  // If we have a simple case, just return now.
3369  const ArrayType *ATy = dyn_cast<ArrayType>(split.first);
3370  if (ATy == 0 || qs.empty())
3371    return ATy;
3372
3373  // Otherwise, we have an array and we have qualifiers on it.  Push the
3374  // qualifiers into the array element type and return a new array type.
3375  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
3376
3377  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
3378    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
3379                                                CAT->getSizeModifier(),
3380                                           CAT->getIndexTypeCVRQualifiers()));
3381  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
3382    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
3383                                                  IAT->getSizeModifier(),
3384                                           IAT->getIndexTypeCVRQualifiers()));
3385
3386  if (const DependentSizedArrayType *DSAT
3387        = dyn_cast<DependentSizedArrayType>(ATy))
3388    return cast<ArrayType>(
3389                     getDependentSizedArrayType(NewEltTy,
3390                                                DSAT->getSizeExpr(),
3391                                                DSAT->getSizeModifier(),
3392                                              DSAT->getIndexTypeCVRQualifiers(),
3393                                                DSAT->getBracketsRange()));
3394
3395  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
3396  return cast<ArrayType>(getVariableArrayType(NewEltTy,
3397                                              VAT->getSizeExpr(),
3398                                              VAT->getSizeModifier(),
3399                                              VAT->getIndexTypeCVRQualifiers(),
3400                                              VAT->getBracketsRange()));
3401}
3402
3403QualType ASTContext::getAdjustedParameterType(QualType T) {
3404  // C99 6.7.5.3p7:
3405  //   A declaration of a parameter as "array of type" shall be
3406  //   adjusted to "qualified pointer to type", where the type
3407  //   qualifiers (if any) are those specified within the [ and ] of
3408  //   the array type derivation.
3409  if (T->isArrayType())
3410    return getArrayDecayedType(T);
3411
3412  // C99 6.7.5.3p8:
3413  //   A declaration of a parameter as "function returning type"
3414  //   shall be adjusted to "pointer to function returning type", as
3415  //   in 6.3.2.1.
3416  if (T->isFunctionType())
3417    return getPointerType(T);
3418
3419  return T;
3420}
3421
3422QualType ASTContext::getSignatureParameterType(QualType T) {
3423  T = getVariableArrayDecayedType(T);
3424  T = getAdjustedParameterType(T);
3425  return T.getUnqualifiedType();
3426}
3427
3428/// getArrayDecayedType - Return the properly qualified result of decaying the
3429/// specified array type to a pointer.  This operation is non-trivial when
3430/// handling typedefs etc.  The canonical type of "T" must be an array type,
3431/// this returns a pointer to a properly qualified element of the array.
3432///
3433/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
3434QualType ASTContext::getArrayDecayedType(QualType Ty) const {
3435  // Get the element type with 'getAsArrayType' so that we don't lose any
3436  // typedefs in the element type of the array.  This also handles propagation
3437  // of type qualifiers from the array type into the element type if present
3438  // (C99 6.7.3p8).
3439  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
3440  assert(PrettyArrayType && "Not an array type!");
3441
3442  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
3443
3444  // int x[restrict 4] ->  int *restrict
3445  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
3446}
3447
3448QualType ASTContext::getBaseElementType(const ArrayType *array) const {
3449  return getBaseElementType(array->getElementType());
3450}
3451
3452QualType ASTContext::getBaseElementType(QualType type) const {
3453  Qualifiers qs;
3454  while (true) {
3455    SplitQualType split = type.getSplitDesugaredType();
3456    const ArrayType *array = split.first->getAsArrayTypeUnsafe();
3457    if (!array) break;
3458
3459    type = array->getElementType();
3460    qs.addConsistentQualifiers(split.second);
3461  }
3462
3463  return getQualifiedType(type, qs);
3464}
3465
3466/// getConstantArrayElementCount - Returns number of constant array elements.
3467uint64_t
3468ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
3469  uint64_t ElementCount = 1;
3470  do {
3471    ElementCount *= CA->getSize().getZExtValue();
3472    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
3473  } while (CA);
3474  return ElementCount;
3475}
3476
3477/// getFloatingRank - Return a relative rank for floating point types.
3478/// This routine will assert if passed a built-in type that isn't a float.
3479static FloatingRank getFloatingRank(QualType T) {
3480  if (const ComplexType *CT = T->getAs<ComplexType>())
3481    return getFloatingRank(CT->getElementType());
3482
3483  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
3484  switch (T->getAs<BuiltinType>()->getKind()) {
3485  default: llvm_unreachable("getFloatingRank(): not a floating type");
3486  case BuiltinType::Float:      return FloatRank;
3487  case BuiltinType::Double:     return DoubleRank;
3488  case BuiltinType::LongDouble: return LongDoubleRank;
3489  }
3490}
3491
3492/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
3493/// point or a complex type (based on typeDomain/typeSize).
3494/// 'typeDomain' is a real floating point or complex type.
3495/// 'typeSize' is a real floating point or complex type.
3496QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
3497                                                       QualType Domain) const {
3498  FloatingRank EltRank = getFloatingRank(Size);
3499  if (Domain->isComplexType()) {
3500    switch (EltRank) {
3501    default: llvm_unreachable("getFloatingRank(): illegal value for rank");
3502    case FloatRank:      return FloatComplexTy;
3503    case DoubleRank:     return DoubleComplexTy;
3504    case LongDoubleRank: return LongDoubleComplexTy;
3505    }
3506  }
3507
3508  assert(Domain->isRealFloatingType() && "Unknown domain!");
3509  switch (EltRank) {
3510  default: llvm_unreachable("getFloatingRank(): illegal value for rank");
3511  case FloatRank:      return FloatTy;
3512  case DoubleRank:     return DoubleTy;
3513  case LongDoubleRank: return LongDoubleTy;
3514  }
3515}
3516
3517/// getFloatingTypeOrder - Compare the rank of the two specified floating
3518/// point types, ignoring the domain of the type (i.e. 'double' ==
3519/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3520/// LHS < RHS, return -1.
3521int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
3522  FloatingRank LHSR = getFloatingRank(LHS);
3523  FloatingRank RHSR = getFloatingRank(RHS);
3524
3525  if (LHSR == RHSR)
3526    return 0;
3527  if (LHSR > RHSR)
3528    return 1;
3529  return -1;
3530}
3531
3532/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
3533/// routine will assert if passed a built-in type that isn't an integer or enum,
3534/// or if it is not canonicalized.
3535unsigned ASTContext::getIntegerRank(const Type *T) const {
3536  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
3537  if (const EnumType* ET = dyn_cast<EnumType>(T))
3538    T = ET->getDecl()->getPromotionType().getTypePtr();
3539
3540  if (T->isSpecificBuiltinType(BuiltinType::WChar_S) ||
3541      T->isSpecificBuiltinType(BuiltinType::WChar_U))
3542    T = getFromTargetType(Target->getWCharType()).getTypePtr();
3543
3544  if (T->isSpecificBuiltinType(BuiltinType::Char16))
3545    T = getFromTargetType(Target->getChar16Type()).getTypePtr();
3546
3547  if (T->isSpecificBuiltinType(BuiltinType::Char32))
3548    T = getFromTargetType(Target->getChar32Type()).getTypePtr();
3549
3550  switch (cast<BuiltinType>(T)->getKind()) {
3551  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
3552  case BuiltinType::Bool:
3553    return 1 + (getIntWidth(BoolTy) << 3);
3554  case BuiltinType::Char_S:
3555  case BuiltinType::Char_U:
3556  case BuiltinType::SChar:
3557  case BuiltinType::UChar:
3558    return 2 + (getIntWidth(CharTy) << 3);
3559  case BuiltinType::Short:
3560  case BuiltinType::UShort:
3561    return 3 + (getIntWidth(ShortTy) << 3);
3562  case BuiltinType::Int:
3563  case BuiltinType::UInt:
3564    return 4 + (getIntWidth(IntTy) << 3);
3565  case BuiltinType::Long:
3566  case BuiltinType::ULong:
3567    return 5 + (getIntWidth(LongTy) << 3);
3568  case BuiltinType::LongLong:
3569  case BuiltinType::ULongLong:
3570    return 6 + (getIntWidth(LongLongTy) << 3);
3571  case BuiltinType::Int128:
3572  case BuiltinType::UInt128:
3573    return 7 + (getIntWidth(Int128Ty) << 3);
3574  }
3575}
3576
3577/// \brief Whether this is a promotable bitfield reference according
3578/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
3579///
3580/// \returns the type this bit-field will promote to, or NULL if no
3581/// promotion occurs.
3582QualType ASTContext::isPromotableBitField(Expr *E) const {
3583  if (E->isTypeDependent() || E->isValueDependent())
3584    return QualType();
3585
3586  FieldDecl *Field = E->getBitField();
3587  if (!Field)
3588    return QualType();
3589
3590  QualType FT = Field->getType();
3591
3592  uint64_t BitWidth = Field->getBitWidthValue(*this);
3593  uint64_t IntSize = getTypeSize(IntTy);
3594  // GCC extension compatibility: if the bit-field size is less than or equal
3595  // to the size of int, it gets promoted no matter what its type is.
3596  // For instance, unsigned long bf : 4 gets promoted to signed int.
3597  if (BitWidth < IntSize)
3598    return IntTy;
3599
3600  if (BitWidth == IntSize)
3601    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
3602
3603  // Types bigger than int are not subject to promotions, and therefore act
3604  // like the base type.
3605  // FIXME: This doesn't quite match what gcc does, but what gcc does here
3606  // is ridiculous.
3607  return QualType();
3608}
3609
3610/// getPromotedIntegerType - Returns the type that Promotable will
3611/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
3612/// integer type.
3613QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
3614  assert(!Promotable.isNull());
3615  assert(Promotable->isPromotableIntegerType());
3616  if (const EnumType *ET = Promotable->getAs<EnumType>())
3617    return ET->getDecl()->getPromotionType();
3618  if (Promotable->isSignedIntegerType())
3619    return IntTy;
3620  uint64_t PromotableSize = getTypeSize(Promotable);
3621  uint64_t IntSize = getTypeSize(IntTy);
3622  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3623  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3624}
3625
3626/// \brief Recurses in pointer/array types until it finds an objc retainable
3627/// type and returns its ownership.
3628Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
3629  while (!T.isNull()) {
3630    if (T.getObjCLifetime() != Qualifiers::OCL_None)
3631      return T.getObjCLifetime();
3632    if (T->isArrayType())
3633      T = getBaseElementType(T);
3634    else if (const PointerType *PT = T->getAs<PointerType>())
3635      T = PT->getPointeeType();
3636    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3637      T = RT->getPointeeType();
3638    else
3639      break;
3640  }
3641
3642  return Qualifiers::OCL_None;
3643}
3644
3645/// getIntegerTypeOrder - Returns the highest ranked integer type:
3646/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3647/// LHS < RHS, return -1.
3648int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
3649  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
3650  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
3651  if (LHSC == RHSC) return 0;
3652
3653  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3654  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3655
3656  unsigned LHSRank = getIntegerRank(LHSC);
3657  unsigned RHSRank = getIntegerRank(RHSC);
3658
3659  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3660    if (LHSRank == RHSRank) return 0;
3661    return LHSRank > RHSRank ? 1 : -1;
3662  }
3663
3664  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3665  if (LHSUnsigned) {
3666    // If the unsigned [LHS] type is larger, return it.
3667    if (LHSRank >= RHSRank)
3668      return 1;
3669
3670    // If the signed type can represent all values of the unsigned type, it
3671    // wins.  Because we are dealing with 2's complement and types that are
3672    // powers of two larger than each other, this is always safe.
3673    return -1;
3674  }
3675
3676  // If the unsigned [RHS] type is larger, return it.
3677  if (RHSRank >= LHSRank)
3678    return -1;
3679
3680  // If the signed type can represent all values of the unsigned type, it
3681  // wins.  Because we are dealing with 2's complement and types that are
3682  // powers of two larger than each other, this is always safe.
3683  return 1;
3684}
3685
3686static RecordDecl *
3687CreateRecordDecl(const ASTContext &Ctx, RecordDecl::TagKind TK,
3688                 DeclContext *DC, IdentifierInfo *Id) {
3689  SourceLocation Loc;
3690  if (Ctx.getLangOptions().CPlusPlus)
3691    return CXXRecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3692  else
3693    return RecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3694}
3695
3696// getCFConstantStringType - Return the type used for constant CFStrings.
3697QualType ASTContext::getCFConstantStringType() const {
3698  if (!CFConstantStringTypeDecl) {
3699    CFConstantStringTypeDecl =
3700      CreateRecordDecl(*this, TTK_Struct, TUDecl,
3701                       &Idents.get("NSConstantString"));
3702    CFConstantStringTypeDecl->startDefinition();
3703
3704    QualType FieldTypes[4];
3705
3706    // const int *isa;
3707    FieldTypes[0] = getPointerType(IntTy.withConst());
3708    // int flags;
3709    FieldTypes[1] = IntTy;
3710    // const char *str;
3711    FieldTypes[2] = getPointerType(CharTy.withConst());
3712    // long length;
3713    FieldTypes[3] = LongTy;
3714
3715    // Create fields
3716    for (unsigned i = 0; i < 4; ++i) {
3717      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3718                                           SourceLocation(),
3719                                           SourceLocation(), 0,
3720                                           FieldTypes[i], /*TInfo=*/0,
3721                                           /*BitWidth=*/0,
3722                                           /*Mutable=*/false,
3723                                           /*HasInit=*/false);
3724      Field->setAccess(AS_public);
3725      CFConstantStringTypeDecl->addDecl(Field);
3726    }
3727
3728    CFConstantStringTypeDecl->completeDefinition();
3729  }
3730
3731  return getTagDeclType(CFConstantStringTypeDecl);
3732}
3733
3734void ASTContext::setCFConstantStringType(QualType T) {
3735  const RecordType *Rec = T->getAs<RecordType>();
3736  assert(Rec && "Invalid CFConstantStringType");
3737  CFConstantStringTypeDecl = Rec->getDecl();
3738}
3739
3740QualType ASTContext::getBlockDescriptorType() const {
3741  if (BlockDescriptorType)
3742    return getTagDeclType(BlockDescriptorType);
3743
3744  RecordDecl *T;
3745  // FIXME: Needs the FlagAppleBlock bit.
3746  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3747                       &Idents.get("__block_descriptor"));
3748  T->startDefinition();
3749
3750  QualType FieldTypes[] = {
3751    UnsignedLongTy,
3752    UnsignedLongTy,
3753  };
3754
3755  const char *FieldNames[] = {
3756    "reserved",
3757    "Size"
3758  };
3759
3760  for (size_t i = 0; i < 2; ++i) {
3761    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3762                                         SourceLocation(),
3763                                         &Idents.get(FieldNames[i]),
3764                                         FieldTypes[i], /*TInfo=*/0,
3765                                         /*BitWidth=*/0,
3766                                         /*Mutable=*/false,
3767                                         /*HasInit=*/false);
3768    Field->setAccess(AS_public);
3769    T->addDecl(Field);
3770  }
3771
3772  T->completeDefinition();
3773
3774  BlockDescriptorType = T;
3775
3776  return getTagDeclType(BlockDescriptorType);
3777}
3778
3779QualType ASTContext::getBlockDescriptorExtendedType() const {
3780  if (BlockDescriptorExtendedType)
3781    return getTagDeclType(BlockDescriptorExtendedType);
3782
3783  RecordDecl *T;
3784  // FIXME: Needs the FlagAppleBlock bit.
3785  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3786                       &Idents.get("__block_descriptor_withcopydispose"));
3787  T->startDefinition();
3788
3789  QualType FieldTypes[] = {
3790    UnsignedLongTy,
3791    UnsignedLongTy,
3792    getPointerType(VoidPtrTy),
3793    getPointerType(VoidPtrTy)
3794  };
3795
3796  const char *FieldNames[] = {
3797    "reserved",
3798    "Size",
3799    "CopyFuncPtr",
3800    "DestroyFuncPtr"
3801  };
3802
3803  for (size_t i = 0; i < 4; ++i) {
3804    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3805                                         SourceLocation(),
3806                                         &Idents.get(FieldNames[i]),
3807                                         FieldTypes[i], /*TInfo=*/0,
3808                                         /*BitWidth=*/0,
3809                                         /*Mutable=*/false,
3810                                         /*HasInit=*/false);
3811    Field->setAccess(AS_public);
3812    T->addDecl(Field);
3813  }
3814
3815  T->completeDefinition();
3816
3817  BlockDescriptorExtendedType = T;
3818
3819  return getTagDeclType(BlockDescriptorExtendedType);
3820}
3821
3822bool ASTContext::BlockRequiresCopying(QualType Ty) const {
3823  if (Ty->isObjCRetainableType())
3824    return true;
3825  if (getLangOptions().CPlusPlus) {
3826    if (const RecordType *RT = Ty->getAs<RecordType>()) {
3827      CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
3828      return RD->hasConstCopyConstructor();
3829
3830    }
3831  }
3832  return false;
3833}
3834
3835QualType
3836ASTContext::BuildByRefType(StringRef DeclName, QualType Ty) const {
3837  //  type = struct __Block_byref_1_X {
3838  //    void *__isa;
3839  //    struct __Block_byref_1_X *__forwarding;
3840  //    unsigned int __flags;
3841  //    unsigned int __size;
3842  //    void *__copy_helper;            // as needed
3843  //    void *__destroy_help            // as needed
3844  //    int X;
3845  //  } *
3846
3847  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3848
3849  // FIXME: Move up
3850  llvm::SmallString<36> Name;
3851  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3852                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3853  RecordDecl *T;
3854  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, &Idents.get(Name.str()));
3855  T->startDefinition();
3856  QualType Int32Ty = IntTy;
3857  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3858  QualType FieldTypes[] = {
3859    getPointerType(VoidPtrTy),
3860    getPointerType(getTagDeclType(T)),
3861    Int32Ty,
3862    Int32Ty,
3863    getPointerType(VoidPtrTy),
3864    getPointerType(VoidPtrTy),
3865    Ty
3866  };
3867
3868  StringRef FieldNames[] = {
3869    "__isa",
3870    "__forwarding",
3871    "__flags",
3872    "__size",
3873    "__copy_helper",
3874    "__destroy_helper",
3875    DeclName,
3876  };
3877
3878  for (size_t i = 0; i < 7; ++i) {
3879    if (!HasCopyAndDispose && i >=4 && i <= 5)
3880      continue;
3881    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3882                                         SourceLocation(),
3883                                         &Idents.get(FieldNames[i]),
3884                                         FieldTypes[i], /*TInfo=*/0,
3885                                         /*BitWidth=*/0, /*Mutable=*/false,
3886                                         /*HasInit=*/false);
3887    Field->setAccess(AS_public);
3888    T->addDecl(Field);
3889  }
3890
3891  T->completeDefinition();
3892
3893  return getPointerType(getTagDeclType(T));
3894}
3895
3896TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
3897  if (!ObjCInstanceTypeDecl)
3898    ObjCInstanceTypeDecl = TypedefDecl::Create(*this,
3899                                               getTranslationUnitDecl(),
3900                                               SourceLocation(),
3901                                               SourceLocation(),
3902                                               &Idents.get("instancetype"),
3903                                     getTrivialTypeSourceInfo(getObjCIdType()));
3904  return ObjCInstanceTypeDecl;
3905}
3906
3907// This returns true if a type has been typedefed to BOOL:
3908// typedef <type> BOOL;
3909static bool isTypeTypedefedAsBOOL(QualType T) {
3910  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3911    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3912      return II->isStr("BOOL");
3913
3914  return false;
3915}
3916
3917/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3918/// purpose.
3919CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
3920  if (!type->isIncompleteArrayType() && type->isIncompleteType())
3921    return CharUnits::Zero();
3922
3923  CharUnits sz = getTypeSizeInChars(type);
3924
3925  // Make all integer and enum types at least as large as an int
3926  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3927    sz = std::max(sz, getTypeSizeInChars(IntTy));
3928  // Treat arrays as pointers, since that's how they're passed in.
3929  else if (type->isArrayType())
3930    sz = getTypeSizeInChars(VoidPtrTy);
3931  return sz;
3932}
3933
3934static inline
3935std::string charUnitsToString(const CharUnits &CU) {
3936  return llvm::itostr(CU.getQuantity());
3937}
3938
3939/// getObjCEncodingForBlock - Return the encoded type for this block
3940/// declaration.
3941std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
3942  std::string S;
3943
3944  const BlockDecl *Decl = Expr->getBlockDecl();
3945  QualType BlockTy =
3946      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3947  // Encode result type.
3948  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3949  // Compute size of all parameters.
3950  // Start with computing size of a pointer in number of bytes.
3951  // FIXME: There might(should) be a better way of doing this computation!
3952  SourceLocation Loc;
3953  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3954  CharUnits ParmOffset = PtrSize;
3955  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3956       E = Decl->param_end(); PI != E; ++PI) {
3957    QualType PType = (*PI)->getType();
3958    CharUnits sz = getObjCEncodingTypeSize(PType);
3959    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3960    ParmOffset += sz;
3961  }
3962  // Size of the argument frame
3963  S += charUnitsToString(ParmOffset);
3964  // Block pointer and offset.
3965  S += "@?0";
3966
3967  // Argument types.
3968  ParmOffset = PtrSize;
3969  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3970       Decl->param_end(); PI != E; ++PI) {
3971    ParmVarDecl *PVDecl = *PI;
3972    QualType PType = PVDecl->getOriginalType();
3973    if (const ArrayType *AT =
3974          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3975      // Use array's original type only if it has known number of
3976      // elements.
3977      if (!isa<ConstantArrayType>(AT))
3978        PType = PVDecl->getType();
3979    } else if (PType->isFunctionType())
3980      PType = PVDecl->getType();
3981    getObjCEncodingForType(PType, S);
3982    S += charUnitsToString(ParmOffset);
3983    ParmOffset += getObjCEncodingTypeSize(PType);
3984  }
3985
3986  return S;
3987}
3988
3989bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
3990                                                std::string& S) {
3991  // Encode result type.
3992  getObjCEncodingForType(Decl->getResultType(), S);
3993  CharUnits ParmOffset;
3994  // Compute size of all parameters.
3995  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
3996       E = Decl->param_end(); PI != E; ++PI) {
3997    QualType PType = (*PI)->getType();
3998    CharUnits sz = getObjCEncodingTypeSize(PType);
3999    if (sz.isZero())
4000      return true;
4001
4002    assert (sz.isPositive() &&
4003        "getObjCEncodingForFunctionDecl - Incomplete param type");
4004    ParmOffset += sz;
4005  }
4006  S += charUnitsToString(ParmOffset);
4007  ParmOffset = CharUnits::Zero();
4008
4009  // Argument types.
4010  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4011       E = Decl->param_end(); PI != E; ++PI) {
4012    ParmVarDecl *PVDecl = *PI;
4013    QualType PType = PVDecl->getOriginalType();
4014    if (const ArrayType *AT =
4015          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4016      // Use array's original type only if it has known number of
4017      // elements.
4018      if (!isa<ConstantArrayType>(AT))
4019        PType = PVDecl->getType();
4020    } else if (PType->isFunctionType())
4021      PType = PVDecl->getType();
4022    getObjCEncodingForType(PType, S);
4023    S += charUnitsToString(ParmOffset);
4024    ParmOffset += getObjCEncodingTypeSize(PType);
4025  }
4026
4027  return false;
4028}
4029
4030/// getObjCEncodingForMethodDecl - Return the encoded type for this method
4031/// declaration.
4032bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
4033                                              std::string& S) const {
4034  // FIXME: This is not very efficient.
4035  // Encode type qualifer, 'in', 'inout', etc. for the return type.
4036  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
4037  // Encode result type.
4038  getObjCEncodingForType(Decl->getResultType(), S);
4039  // Compute size of all parameters.
4040  // Start with computing size of a pointer in number of bytes.
4041  // FIXME: There might(should) be a better way of doing this computation!
4042  SourceLocation Loc;
4043  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4044  // The first two arguments (self and _cmd) are pointers; account for
4045  // their size.
4046  CharUnits ParmOffset = 2 * PtrSize;
4047  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4048       E = Decl->sel_param_end(); PI != E; ++PI) {
4049    QualType PType = (*PI)->getType();
4050    CharUnits sz = getObjCEncodingTypeSize(PType);
4051    if (sz.isZero())
4052      return true;
4053
4054    assert (sz.isPositive() &&
4055        "getObjCEncodingForMethodDecl - Incomplete param type");
4056    ParmOffset += sz;
4057  }
4058  S += charUnitsToString(ParmOffset);
4059  S += "@0:";
4060  S += charUnitsToString(PtrSize);
4061
4062  // Argument types.
4063  ParmOffset = 2 * PtrSize;
4064  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4065       E = Decl->sel_param_end(); PI != E; ++PI) {
4066    const ParmVarDecl *PVDecl = *PI;
4067    QualType PType = PVDecl->getOriginalType();
4068    if (const ArrayType *AT =
4069          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4070      // Use array's original type only if it has known number of
4071      // elements.
4072      if (!isa<ConstantArrayType>(AT))
4073        PType = PVDecl->getType();
4074    } else if (PType->isFunctionType())
4075      PType = PVDecl->getType();
4076    // Process argument qualifiers for user supplied arguments; such as,
4077    // 'in', 'inout', etc.
4078    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
4079    getObjCEncodingForType(PType, S);
4080    S += charUnitsToString(ParmOffset);
4081    ParmOffset += getObjCEncodingTypeSize(PType);
4082  }
4083
4084  return false;
4085}
4086
4087/// getObjCEncodingForPropertyDecl - Return the encoded type for this
4088/// property declaration. If non-NULL, Container must be either an
4089/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
4090/// NULL when getting encodings for protocol properties.
4091/// Property attributes are stored as a comma-delimited C string. The simple
4092/// attributes readonly and bycopy are encoded as single characters. The
4093/// parametrized attributes, getter=name, setter=name, and ivar=name, are
4094/// encoded as single characters, followed by an identifier. Property types
4095/// are also encoded as a parametrized attribute. The characters used to encode
4096/// these attributes are defined by the following enumeration:
4097/// @code
4098/// enum PropertyAttributes {
4099/// kPropertyReadOnly = 'R',   // property is read-only.
4100/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
4101/// kPropertyByref = '&',  // property is a reference to the value last assigned
4102/// kPropertyDynamic = 'D',    // property is dynamic
4103/// kPropertyGetter = 'G',     // followed by getter selector name
4104/// kPropertySetter = 'S',     // followed by setter selector name
4105/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
4106/// kPropertyType = 't'              // followed by old-style type encoding.
4107/// kPropertyWeak = 'W'              // 'weak' property
4108/// kPropertyStrong = 'P'            // property GC'able
4109/// kPropertyNonAtomic = 'N'         // property non-atomic
4110/// };
4111/// @endcode
4112void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
4113                                                const Decl *Container,
4114                                                std::string& S) const {
4115  // Collect information from the property implementation decl(s).
4116  bool Dynamic = false;
4117  ObjCPropertyImplDecl *SynthesizePID = 0;
4118
4119  // FIXME: Duplicated code due to poor abstraction.
4120  if (Container) {
4121    if (const ObjCCategoryImplDecl *CID =
4122        dyn_cast<ObjCCategoryImplDecl>(Container)) {
4123      for (ObjCCategoryImplDecl::propimpl_iterator
4124             i = CID->propimpl_begin(), e = CID->propimpl_end();
4125           i != e; ++i) {
4126        ObjCPropertyImplDecl *PID = *i;
4127        if (PID->getPropertyDecl() == PD) {
4128          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4129            Dynamic = true;
4130          } else {
4131            SynthesizePID = PID;
4132          }
4133        }
4134      }
4135    } else {
4136      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
4137      for (ObjCCategoryImplDecl::propimpl_iterator
4138             i = OID->propimpl_begin(), e = OID->propimpl_end();
4139           i != e; ++i) {
4140        ObjCPropertyImplDecl *PID = *i;
4141        if (PID->getPropertyDecl() == PD) {
4142          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4143            Dynamic = true;
4144          } else {
4145            SynthesizePID = PID;
4146          }
4147        }
4148      }
4149    }
4150  }
4151
4152  // FIXME: This is not very efficient.
4153  S = "T";
4154
4155  // Encode result type.
4156  // GCC has some special rules regarding encoding of properties which
4157  // closely resembles encoding of ivars.
4158  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
4159                             true /* outermost type */,
4160                             true /* encoding for property */);
4161
4162  if (PD->isReadOnly()) {
4163    S += ",R";
4164  } else {
4165    switch (PD->getSetterKind()) {
4166    case ObjCPropertyDecl::Assign: break;
4167    case ObjCPropertyDecl::Copy:   S += ",C"; break;
4168    case ObjCPropertyDecl::Retain: S += ",&"; break;
4169    case ObjCPropertyDecl::Weak:   S += ",W"; break;
4170    }
4171  }
4172
4173  // It really isn't clear at all what this means, since properties
4174  // are "dynamic by default".
4175  if (Dynamic)
4176    S += ",D";
4177
4178  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
4179    S += ",N";
4180
4181  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
4182    S += ",G";
4183    S += PD->getGetterName().getAsString();
4184  }
4185
4186  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
4187    S += ",S";
4188    S += PD->getSetterName().getAsString();
4189  }
4190
4191  if (SynthesizePID) {
4192    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
4193    S += ",V";
4194    S += OID->getNameAsString();
4195  }
4196
4197  // FIXME: OBJCGC: weak & strong
4198}
4199
4200/// getLegacyIntegralTypeEncoding -
4201/// Another legacy compatibility encoding: 32-bit longs are encoded as
4202/// 'l' or 'L' , but not always.  For typedefs, we need to use
4203/// 'i' or 'I' instead if encoding a struct field, or a pointer!
4204///
4205void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
4206  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
4207    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
4208      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
4209        PointeeTy = UnsignedIntTy;
4210      else
4211        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
4212          PointeeTy = IntTy;
4213    }
4214  }
4215}
4216
4217void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
4218                                        const FieldDecl *Field) const {
4219  // We follow the behavior of gcc, expanding structures which are
4220  // directly pointed to, and expanding embedded structures. Note that
4221  // these rules are sufficient to prevent recursive encoding of the
4222  // same type.
4223  getObjCEncodingForTypeImpl(T, S, true, true, Field,
4224                             true /* outermost type */);
4225}
4226
4227static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
4228    switch (T->getAs<BuiltinType>()->getKind()) {
4229    default: llvm_unreachable("Unhandled builtin type kind");
4230    case BuiltinType::Void:       return 'v';
4231    case BuiltinType::Bool:       return 'B';
4232    case BuiltinType::Char_U:
4233    case BuiltinType::UChar:      return 'C';
4234    case BuiltinType::UShort:     return 'S';
4235    case BuiltinType::UInt:       return 'I';
4236    case BuiltinType::ULong:
4237        return C->getIntWidth(T) == 32 ? 'L' : 'Q';
4238    case BuiltinType::UInt128:    return 'T';
4239    case BuiltinType::ULongLong:  return 'Q';
4240    case BuiltinType::Char_S:
4241    case BuiltinType::SChar:      return 'c';
4242    case BuiltinType::Short:      return 's';
4243    case BuiltinType::WChar_S:
4244    case BuiltinType::WChar_U:
4245    case BuiltinType::Int:        return 'i';
4246    case BuiltinType::Long:
4247      return C->getIntWidth(T) == 32 ? 'l' : 'q';
4248    case BuiltinType::LongLong:   return 'q';
4249    case BuiltinType::Int128:     return 't';
4250    case BuiltinType::Float:      return 'f';
4251    case BuiltinType::Double:     return 'd';
4252    case BuiltinType::LongDouble: return 'D';
4253    }
4254}
4255
4256static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
4257  EnumDecl *Enum = ET->getDecl();
4258
4259  // The encoding of an non-fixed enum type is always 'i', regardless of size.
4260  if (!Enum->isFixed())
4261    return 'i';
4262
4263  // The encoding of a fixed enum type matches its fixed underlying type.
4264  return ObjCEncodingForPrimitiveKind(C, Enum->getIntegerType());
4265}
4266
4267static void EncodeBitField(const ASTContext *Ctx, std::string& S,
4268                           QualType T, const FieldDecl *FD) {
4269  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
4270  S += 'b';
4271  // The NeXT runtime encodes bit fields as b followed by the number of bits.
4272  // The GNU runtime requires more information; bitfields are encoded as b,
4273  // then the offset (in bits) of the first element, then the type of the
4274  // bitfield, then the size in bits.  For example, in this structure:
4275  //
4276  // struct
4277  // {
4278  //    int integer;
4279  //    int flags:2;
4280  // };
4281  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
4282  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
4283  // information is not especially sensible, but we're stuck with it for
4284  // compatibility with GCC, although providing it breaks anything that
4285  // actually uses runtime introspection and wants to work on both runtimes...
4286  if (!Ctx->getLangOptions().NeXTRuntime) {
4287    const RecordDecl *RD = FD->getParent();
4288    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
4289    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
4290    if (const EnumType *ET = T->getAs<EnumType>())
4291      S += ObjCEncodingForEnumType(Ctx, ET);
4292    else
4293      S += ObjCEncodingForPrimitiveKind(Ctx, T);
4294  }
4295  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
4296}
4297
4298// FIXME: Use SmallString for accumulating string.
4299void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
4300                                            bool ExpandPointedToStructures,
4301                                            bool ExpandStructures,
4302                                            const FieldDecl *FD,
4303                                            bool OutermostType,
4304                                            bool EncodingProperty,
4305                                            bool StructField) const {
4306  if (T->getAs<BuiltinType>()) {
4307    if (FD && FD->isBitField())
4308      return EncodeBitField(this, S, T, FD);
4309    S += ObjCEncodingForPrimitiveKind(this, T);
4310    return;
4311  }
4312
4313  if (const ComplexType *CT = T->getAs<ComplexType>()) {
4314    S += 'j';
4315    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
4316                               false);
4317    return;
4318  }
4319
4320  // encoding for pointer or r3eference types.
4321  QualType PointeeTy;
4322  if (const PointerType *PT = T->getAs<PointerType>()) {
4323    if (PT->isObjCSelType()) {
4324      S += ':';
4325      return;
4326    }
4327    PointeeTy = PT->getPointeeType();
4328  }
4329  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4330    PointeeTy = RT->getPointeeType();
4331  if (!PointeeTy.isNull()) {
4332    bool isReadOnly = false;
4333    // For historical/compatibility reasons, the read-only qualifier of the
4334    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
4335    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
4336    // Also, do not emit the 'r' for anything but the outermost type!
4337    if (isa<TypedefType>(T.getTypePtr())) {
4338      if (OutermostType && T.isConstQualified()) {
4339        isReadOnly = true;
4340        S += 'r';
4341      }
4342    } else if (OutermostType) {
4343      QualType P = PointeeTy;
4344      while (P->getAs<PointerType>())
4345        P = P->getAs<PointerType>()->getPointeeType();
4346      if (P.isConstQualified()) {
4347        isReadOnly = true;
4348        S += 'r';
4349      }
4350    }
4351    if (isReadOnly) {
4352      // Another legacy compatibility encoding. Some ObjC qualifier and type
4353      // combinations need to be rearranged.
4354      // Rewrite "in const" from "nr" to "rn"
4355      if (StringRef(S).endswith("nr"))
4356        S.replace(S.end()-2, S.end(), "rn");
4357    }
4358
4359    if (PointeeTy->isCharType()) {
4360      // char pointer types should be encoded as '*' unless it is a
4361      // type that has been typedef'd to 'BOOL'.
4362      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
4363        S += '*';
4364        return;
4365      }
4366    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
4367      // GCC binary compat: Need to convert "struct objc_class *" to "#".
4368      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
4369        S += '#';
4370        return;
4371      }
4372      // GCC binary compat: Need to convert "struct objc_object *" to "@".
4373      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
4374        S += '@';
4375        return;
4376      }
4377      // fall through...
4378    }
4379    S += '^';
4380    getLegacyIntegralTypeEncoding(PointeeTy);
4381
4382    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
4383                               NULL);
4384    return;
4385  }
4386
4387  if (const ArrayType *AT =
4388      // Ignore type qualifiers etc.
4389        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
4390    if (isa<IncompleteArrayType>(AT) && !StructField) {
4391      // Incomplete arrays are encoded as a pointer to the array element.
4392      S += '^';
4393
4394      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4395                                 false, ExpandStructures, FD);
4396    } else {
4397      S += '[';
4398
4399      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
4400        if (getTypeSize(CAT->getElementType()) == 0)
4401          S += '0';
4402        else
4403          S += llvm::utostr(CAT->getSize().getZExtValue());
4404      } else {
4405        //Variable length arrays are encoded as a regular array with 0 elements.
4406        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
4407               "Unknown array type!");
4408        S += '0';
4409      }
4410
4411      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4412                                 false, ExpandStructures, FD);
4413      S += ']';
4414    }
4415    return;
4416  }
4417
4418  if (T->getAs<FunctionType>()) {
4419    S += '?';
4420    return;
4421  }
4422
4423  if (const RecordType *RTy = T->getAs<RecordType>()) {
4424    RecordDecl *RDecl = RTy->getDecl();
4425    S += RDecl->isUnion() ? '(' : '{';
4426    // Anonymous structures print as '?'
4427    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
4428      S += II->getName();
4429      if (ClassTemplateSpecializationDecl *Spec
4430          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
4431        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
4432        std::string TemplateArgsStr
4433          = TemplateSpecializationType::PrintTemplateArgumentList(
4434                                            TemplateArgs.data(),
4435                                            TemplateArgs.size(),
4436                                            (*this).getPrintingPolicy());
4437
4438        S += TemplateArgsStr;
4439      }
4440    } else {
4441      S += '?';
4442    }
4443    if (ExpandStructures) {
4444      S += '=';
4445      if (!RDecl->isUnion()) {
4446        getObjCEncodingForStructureImpl(RDecl, S, FD);
4447      } else {
4448        for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4449                                     FieldEnd = RDecl->field_end();
4450             Field != FieldEnd; ++Field) {
4451          if (FD) {
4452            S += '"';
4453            S += Field->getNameAsString();
4454            S += '"';
4455          }
4456
4457          // Special case bit-fields.
4458          if (Field->isBitField()) {
4459            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
4460                                       (*Field));
4461          } else {
4462            QualType qt = Field->getType();
4463            getLegacyIntegralTypeEncoding(qt);
4464            getObjCEncodingForTypeImpl(qt, S, false, true,
4465                                       FD, /*OutermostType*/false,
4466                                       /*EncodingProperty*/false,
4467                                       /*StructField*/true);
4468          }
4469        }
4470      }
4471    }
4472    S += RDecl->isUnion() ? ')' : '}';
4473    return;
4474  }
4475
4476  if (const EnumType *ET = T->getAs<EnumType>()) {
4477    if (FD && FD->isBitField())
4478      EncodeBitField(this, S, T, FD);
4479    else
4480      S += ObjCEncodingForEnumType(this, ET);
4481    return;
4482  }
4483
4484  if (T->isBlockPointerType()) {
4485    S += "@?"; // Unlike a pointer-to-function, which is "^?".
4486    return;
4487  }
4488
4489  // Ignore protocol qualifiers when mangling at this level.
4490  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
4491    T = OT->getBaseType();
4492
4493  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
4494    // @encode(class_name)
4495    ObjCInterfaceDecl *OI = OIT->getDecl();
4496    S += '{';
4497    const IdentifierInfo *II = OI->getIdentifier();
4498    S += II->getName();
4499    S += '=';
4500    SmallVector<const ObjCIvarDecl*, 32> Ivars;
4501    DeepCollectObjCIvars(OI, true, Ivars);
4502    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
4503      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
4504      if (Field->isBitField())
4505        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
4506      else
4507        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
4508    }
4509    S += '}';
4510    return;
4511  }
4512
4513  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
4514    if (OPT->isObjCIdType()) {
4515      S += '@';
4516      return;
4517    }
4518
4519    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
4520      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
4521      // Since this is a binary compatibility issue, need to consult with runtime
4522      // folks. Fortunately, this is a *very* obsure construct.
4523      S += '#';
4524      return;
4525    }
4526
4527    if (OPT->isObjCQualifiedIdType()) {
4528      getObjCEncodingForTypeImpl(getObjCIdType(), S,
4529                                 ExpandPointedToStructures,
4530                                 ExpandStructures, FD);
4531      if (FD || EncodingProperty) {
4532        // Note that we do extended encoding of protocol qualifer list
4533        // Only when doing ivar or property encoding.
4534        S += '"';
4535        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4536             E = OPT->qual_end(); I != E; ++I) {
4537          S += '<';
4538          S += (*I)->getNameAsString();
4539          S += '>';
4540        }
4541        S += '"';
4542      }
4543      return;
4544    }
4545
4546    QualType PointeeTy = OPT->getPointeeType();
4547    if (!EncodingProperty &&
4548        isa<TypedefType>(PointeeTy.getTypePtr())) {
4549      // Another historical/compatibility reason.
4550      // We encode the underlying type which comes out as
4551      // {...};
4552      S += '^';
4553      getObjCEncodingForTypeImpl(PointeeTy, S,
4554                                 false, ExpandPointedToStructures,
4555                                 NULL);
4556      return;
4557    }
4558
4559    S += '@';
4560    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
4561      S += '"';
4562      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4563      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4564           E = OPT->qual_end(); I != E; ++I) {
4565        S += '<';
4566        S += (*I)->getNameAsString();
4567        S += '>';
4568      }
4569      S += '"';
4570    }
4571    return;
4572  }
4573
4574  // gcc just blithely ignores member pointers.
4575  // TODO: maybe there should be a mangling for these
4576  if (T->getAs<MemberPointerType>())
4577    return;
4578
4579  if (T->isVectorType()) {
4580    // This matches gcc's encoding, even though technically it is
4581    // insufficient.
4582    // FIXME. We should do a better job than gcc.
4583    return;
4584  }
4585
4586  llvm_unreachable("@encode for type not implemented!");
4587}
4588
4589void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
4590                                                 std::string &S,
4591                                                 const FieldDecl *FD,
4592                                                 bool includeVBases) const {
4593  assert(RDecl && "Expected non-null RecordDecl");
4594  assert(!RDecl->isUnion() && "Should not be called for unions");
4595  if (!RDecl->getDefinition())
4596    return;
4597
4598  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
4599  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
4600  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
4601
4602  if (CXXRec) {
4603    for (CXXRecordDecl::base_class_iterator
4604           BI = CXXRec->bases_begin(),
4605           BE = CXXRec->bases_end(); BI != BE; ++BI) {
4606      if (!BI->isVirtual()) {
4607        CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4608        if (base->isEmpty())
4609          continue;
4610        uint64_t offs = layout.getBaseClassOffsetInBits(base);
4611        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4612                                  std::make_pair(offs, base));
4613      }
4614    }
4615  }
4616
4617  unsigned i = 0;
4618  for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4619                               FieldEnd = RDecl->field_end();
4620       Field != FieldEnd; ++Field, ++i) {
4621    uint64_t offs = layout.getFieldOffset(i);
4622    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4623                              std::make_pair(offs, *Field));
4624  }
4625
4626  if (CXXRec && includeVBases) {
4627    for (CXXRecordDecl::base_class_iterator
4628           BI = CXXRec->vbases_begin(),
4629           BE = CXXRec->vbases_end(); BI != BE; ++BI) {
4630      CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4631      if (base->isEmpty())
4632        continue;
4633      uint64_t offs = layout.getVBaseClassOffsetInBits(base);
4634      if (FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
4635        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
4636                                  std::make_pair(offs, base));
4637    }
4638  }
4639
4640  CharUnits size;
4641  if (CXXRec) {
4642    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
4643  } else {
4644    size = layout.getSize();
4645  }
4646
4647  uint64_t CurOffs = 0;
4648  std::multimap<uint64_t, NamedDecl *>::iterator
4649    CurLayObj = FieldOrBaseOffsets.begin();
4650
4651  if ((CurLayObj != FieldOrBaseOffsets.end() && CurLayObj->first != 0) ||
4652      (CurLayObj == FieldOrBaseOffsets.end() &&
4653         CXXRec && CXXRec->isDynamicClass())) {
4654    assert(CXXRec && CXXRec->isDynamicClass() &&
4655           "Offset 0 was empty but no VTable ?");
4656    if (FD) {
4657      S += "\"_vptr$";
4658      std::string recname = CXXRec->getNameAsString();
4659      if (recname.empty()) recname = "?";
4660      S += recname;
4661      S += '"';
4662    }
4663    S += "^^?";
4664    CurOffs += getTypeSize(VoidPtrTy);
4665  }
4666
4667  if (!RDecl->hasFlexibleArrayMember()) {
4668    // Mark the end of the structure.
4669    uint64_t offs = toBits(size);
4670    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4671                              std::make_pair(offs, (NamedDecl*)0));
4672  }
4673
4674  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
4675    assert(CurOffs <= CurLayObj->first);
4676
4677    if (CurOffs < CurLayObj->first) {
4678      uint64_t padding = CurLayObj->first - CurOffs;
4679      // FIXME: There doesn't seem to be a way to indicate in the encoding that
4680      // packing/alignment of members is different that normal, in which case
4681      // the encoding will be out-of-sync with the real layout.
4682      // If the runtime switches to just consider the size of types without
4683      // taking into account alignment, we could make padding explicit in the
4684      // encoding (e.g. using arrays of chars). The encoding strings would be
4685      // longer then though.
4686      CurOffs += padding;
4687    }
4688
4689    NamedDecl *dcl = CurLayObj->second;
4690    if (dcl == 0)
4691      break; // reached end of structure.
4692
4693    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
4694      // We expand the bases without their virtual bases since those are going
4695      // in the initial structure. Note that this differs from gcc which
4696      // expands virtual bases each time one is encountered in the hierarchy,
4697      // making the encoding type bigger than it really is.
4698      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false);
4699      assert(!base->isEmpty());
4700      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
4701    } else {
4702      FieldDecl *field = cast<FieldDecl>(dcl);
4703      if (FD) {
4704        S += '"';
4705        S += field->getNameAsString();
4706        S += '"';
4707      }
4708
4709      if (field->isBitField()) {
4710        EncodeBitField(this, S, field->getType(), field);
4711        CurOffs += field->getBitWidthValue(*this);
4712      } else {
4713        QualType qt = field->getType();
4714        getLegacyIntegralTypeEncoding(qt);
4715        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
4716                                   /*OutermostType*/false,
4717                                   /*EncodingProperty*/false,
4718                                   /*StructField*/true);
4719        CurOffs += getTypeSize(field->getType());
4720      }
4721    }
4722  }
4723}
4724
4725void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4726                                                 std::string& S) const {
4727  if (QT & Decl::OBJC_TQ_In)
4728    S += 'n';
4729  if (QT & Decl::OBJC_TQ_Inout)
4730    S += 'N';
4731  if (QT & Decl::OBJC_TQ_Out)
4732    S += 'o';
4733  if (QT & Decl::OBJC_TQ_Bycopy)
4734    S += 'O';
4735  if (QT & Decl::OBJC_TQ_Byref)
4736    S += 'R';
4737  if (QT & Decl::OBJC_TQ_Oneway)
4738    S += 'V';
4739}
4740
4741void ASTContext::setBuiltinVaListType(QualType T) {
4742  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4743
4744  BuiltinVaListType = T;
4745}
4746
4747TypedefDecl *ASTContext::getObjCIdDecl() const {
4748  if (!ObjCIdDecl) {
4749    QualType T = getObjCObjectType(ObjCBuiltinIdTy, 0, 0);
4750    T = getObjCObjectPointerType(T);
4751    TypeSourceInfo *IdInfo = getTrivialTypeSourceInfo(T);
4752    ObjCIdDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4753                                     getTranslationUnitDecl(),
4754                                     SourceLocation(), SourceLocation(),
4755                                     &Idents.get("id"), IdInfo);
4756  }
4757
4758  return ObjCIdDecl;
4759}
4760
4761TypedefDecl *ASTContext::getObjCSelDecl() const {
4762  if (!ObjCSelDecl) {
4763    QualType SelT = getPointerType(ObjCBuiltinSelTy);
4764    TypeSourceInfo *SelInfo = getTrivialTypeSourceInfo(SelT);
4765    ObjCSelDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4766                                      getTranslationUnitDecl(),
4767                                      SourceLocation(), SourceLocation(),
4768                                      &Idents.get("SEL"), SelInfo);
4769  }
4770  return ObjCSelDecl;
4771}
4772
4773void ASTContext::setObjCProtoType(QualType QT) {
4774  ObjCProtoType = QT;
4775}
4776
4777TypedefDecl *ASTContext::getObjCClassDecl() const {
4778  if (!ObjCClassDecl) {
4779    QualType T = getObjCObjectType(ObjCBuiltinClassTy, 0, 0);
4780    T = getObjCObjectPointerType(T);
4781    TypeSourceInfo *ClassInfo = getTrivialTypeSourceInfo(T);
4782    ObjCClassDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4783                                        getTranslationUnitDecl(),
4784                                        SourceLocation(), SourceLocation(),
4785                                        &Idents.get("Class"), ClassInfo);
4786  }
4787
4788  return ObjCClassDecl;
4789}
4790
4791void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4792  assert(ObjCConstantStringType.isNull() &&
4793         "'NSConstantString' type already set!");
4794
4795  ObjCConstantStringType = getObjCInterfaceType(Decl);
4796}
4797
4798/// \brief Retrieve the template name that corresponds to a non-empty
4799/// lookup.
4800TemplateName
4801ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4802                                      UnresolvedSetIterator End) const {
4803  unsigned size = End - Begin;
4804  assert(size > 1 && "set is not overloaded!");
4805
4806  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4807                          size * sizeof(FunctionTemplateDecl*));
4808  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4809
4810  NamedDecl **Storage = OT->getStorage();
4811  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4812    NamedDecl *D = *I;
4813    assert(isa<FunctionTemplateDecl>(D) ||
4814           (isa<UsingShadowDecl>(D) &&
4815            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4816    *Storage++ = D;
4817  }
4818
4819  return TemplateName(OT);
4820}
4821
4822/// \brief Retrieve the template name that represents a qualified
4823/// template name such as \c std::vector.
4824TemplateName
4825ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4826                                     bool TemplateKeyword,
4827                                     TemplateDecl *Template) const {
4828  assert(NNS && "Missing nested-name-specifier in qualified template name");
4829
4830  // FIXME: Canonicalization?
4831  llvm::FoldingSetNodeID ID;
4832  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4833
4834  void *InsertPos = 0;
4835  QualifiedTemplateName *QTN =
4836    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4837  if (!QTN) {
4838    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4839    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4840  }
4841
4842  return TemplateName(QTN);
4843}
4844
4845/// \brief Retrieve the template name that represents a dependent
4846/// template name such as \c MetaFun::template apply.
4847TemplateName
4848ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4849                                     const IdentifierInfo *Name) const {
4850  assert((!NNS || NNS->isDependent()) &&
4851         "Nested name specifier must be dependent");
4852
4853  llvm::FoldingSetNodeID ID;
4854  DependentTemplateName::Profile(ID, NNS, Name);
4855
4856  void *InsertPos = 0;
4857  DependentTemplateName *QTN =
4858    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4859
4860  if (QTN)
4861    return TemplateName(QTN);
4862
4863  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4864  if (CanonNNS == NNS) {
4865    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4866  } else {
4867    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4868    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4869    DependentTemplateName *CheckQTN =
4870      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4871    assert(!CheckQTN && "Dependent type name canonicalization broken");
4872    (void)CheckQTN;
4873  }
4874
4875  DependentTemplateNames.InsertNode(QTN, InsertPos);
4876  return TemplateName(QTN);
4877}
4878
4879/// \brief Retrieve the template name that represents a dependent
4880/// template name such as \c MetaFun::template operator+.
4881TemplateName
4882ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4883                                     OverloadedOperatorKind Operator) const {
4884  assert((!NNS || NNS->isDependent()) &&
4885         "Nested name specifier must be dependent");
4886
4887  llvm::FoldingSetNodeID ID;
4888  DependentTemplateName::Profile(ID, NNS, Operator);
4889
4890  void *InsertPos = 0;
4891  DependentTemplateName *QTN
4892    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4893
4894  if (QTN)
4895    return TemplateName(QTN);
4896
4897  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4898  if (CanonNNS == NNS) {
4899    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4900  } else {
4901    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4902    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4903
4904    DependentTemplateName *CheckQTN
4905      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4906    assert(!CheckQTN && "Dependent template name canonicalization broken");
4907    (void)CheckQTN;
4908  }
4909
4910  DependentTemplateNames.InsertNode(QTN, InsertPos);
4911  return TemplateName(QTN);
4912}
4913
4914TemplateName
4915ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
4916                                         TemplateName replacement) const {
4917  llvm::FoldingSetNodeID ID;
4918  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
4919
4920  void *insertPos = 0;
4921  SubstTemplateTemplateParmStorage *subst
4922    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
4923
4924  if (!subst) {
4925    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
4926    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
4927  }
4928
4929  return TemplateName(subst);
4930}
4931
4932TemplateName
4933ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
4934                                       const TemplateArgument &ArgPack) const {
4935  ASTContext &Self = const_cast<ASTContext &>(*this);
4936  llvm::FoldingSetNodeID ID;
4937  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
4938
4939  void *InsertPos = 0;
4940  SubstTemplateTemplateParmPackStorage *Subst
4941    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
4942
4943  if (!Subst) {
4944    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
4945                                                           ArgPack.pack_size(),
4946                                                         ArgPack.pack_begin());
4947    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
4948  }
4949
4950  return TemplateName(Subst);
4951}
4952
4953/// getFromTargetType - Given one of the integer types provided by
4954/// TargetInfo, produce the corresponding type. The unsigned @p Type
4955/// is actually a value of type @c TargetInfo::IntType.
4956CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4957  switch (Type) {
4958  case TargetInfo::NoInt: return CanQualType();
4959  case TargetInfo::SignedShort: return ShortTy;
4960  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4961  case TargetInfo::SignedInt: return IntTy;
4962  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4963  case TargetInfo::SignedLong: return LongTy;
4964  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4965  case TargetInfo::SignedLongLong: return LongLongTy;
4966  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4967  }
4968
4969  llvm_unreachable("Unhandled TargetInfo::IntType value");
4970}
4971
4972//===----------------------------------------------------------------------===//
4973//                        Type Predicates.
4974//===----------------------------------------------------------------------===//
4975
4976/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4977/// garbage collection attribute.
4978///
4979Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
4980  if (getLangOptions().getGC() == LangOptions::NonGC)
4981    return Qualifiers::GCNone;
4982
4983  assert(getLangOptions().ObjC1);
4984  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
4985
4986  // Default behaviour under objective-C's gc is for ObjC pointers
4987  // (or pointers to them) be treated as though they were declared
4988  // as __strong.
4989  if (GCAttrs == Qualifiers::GCNone) {
4990    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4991      return Qualifiers::Strong;
4992    else if (Ty->isPointerType())
4993      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4994  } else {
4995    // It's not valid to set GC attributes on anything that isn't a
4996    // pointer.
4997#ifndef NDEBUG
4998    QualType CT = Ty->getCanonicalTypeInternal();
4999    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
5000      CT = AT->getElementType();
5001    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
5002#endif
5003  }
5004  return GCAttrs;
5005}
5006
5007//===----------------------------------------------------------------------===//
5008//                        Type Compatibility Testing
5009//===----------------------------------------------------------------------===//
5010
5011/// areCompatVectorTypes - Return true if the two specified vector types are
5012/// compatible.
5013static bool areCompatVectorTypes(const VectorType *LHS,
5014                                 const VectorType *RHS) {
5015  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
5016  return LHS->getElementType() == RHS->getElementType() &&
5017         LHS->getNumElements() == RHS->getNumElements();
5018}
5019
5020bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
5021                                          QualType SecondVec) {
5022  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
5023  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
5024
5025  if (hasSameUnqualifiedType(FirstVec, SecondVec))
5026    return true;
5027
5028  // Treat Neon vector types and most AltiVec vector types as if they are the
5029  // equivalent GCC vector types.
5030  const VectorType *First = FirstVec->getAs<VectorType>();
5031  const VectorType *Second = SecondVec->getAs<VectorType>();
5032  if (First->getNumElements() == Second->getNumElements() &&
5033      hasSameType(First->getElementType(), Second->getElementType()) &&
5034      First->getVectorKind() != VectorType::AltiVecPixel &&
5035      First->getVectorKind() != VectorType::AltiVecBool &&
5036      Second->getVectorKind() != VectorType::AltiVecPixel &&
5037      Second->getVectorKind() != VectorType::AltiVecBool)
5038    return true;
5039
5040  return false;
5041}
5042
5043//===----------------------------------------------------------------------===//
5044// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
5045//===----------------------------------------------------------------------===//
5046
5047/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
5048/// inheritance hierarchy of 'rProto'.
5049bool
5050ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
5051                                           ObjCProtocolDecl *rProto) const {
5052  if (lProto == rProto)
5053    return true;
5054  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
5055       E = rProto->protocol_end(); PI != E; ++PI)
5056    if (ProtocolCompatibleWithProtocol(lProto, *PI))
5057      return true;
5058  return false;
5059}
5060
5061/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
5062/// return true if lhs's protocols conform to rhs's protocol; false
5063/// otherwise.
5064bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
5065  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
5066    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
5067  return false;
5068}
5069
5070/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
5071/// Class<p1, ...>.
5072bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
5073                                                      QualType rhs) {
5074  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
5075  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5076  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
5077
5078  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5079       E = lhsQID->qual_end(); I != E; ++I) {
5080    bool match = false;
5081    ObjCProtocolDecl *lhsProto = *I;
5082    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5083         E = rhsOPT->qual_end(); J != E; ++J) {
5084      ObjCProtocolDecl *rhsProto = *J;
5085      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
5086        match = true;
5087        break;
5088      }
5089    }
5090    if (!match)
5091      return false;
5092  }
5093  return true;
5094}
5095
5096/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
5097/// ObjCQualifiedIDType.
5098bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
5099                                                   bool compare) {
5100  // Allow id<P..> and an 'id' or void* type in all cases.
5101  if (lhs->isVoidPointerType() ||
5102      lhs->isObjCIdType() || lhs->isObjCClassType())
5103    return true;
5104  else if (rhs->isVoidPointerType() ||
5105           rhs->isObjCIdType() || rhs->isObjCClassType())
5106    return true;
5107
5108  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
5109    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5110
5111    if (!rhsOPT) return false;
5112
5113    if (rhsOPT->qual_empty()) {
5114      // If the RHS is a unqualified interface pointer "NSString*",
5115      // make sure we check the class hierarchy.
5116      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5117        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5118             E = lhsQID->qual_end(); I != E; ++I) {
5119          // when comparing an id<P> on lhs with a static type on rhs,
5120          // see if static class implements all of id's protocols, directly or
5121          // through its super class and categories.
5122          if (!rhsID->ClassImplementsProtocol(*I, true))
5123            return false;
5124        }
5125      }
5126      // If there are no qualifiers and no interface, we have an 'id'.
5127      return true;
5128    }
5129    // Both the right and left sides have qualifiers.
5130    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5131         E = lhsQID->qual_end(); I != E; ++I) {
5132      ObjCProtocolDecl *lhsProto = *I;
5133      bool match = false;
5134
5135      // when comparing an id<P> on lhs with a static type on rhs,
5136      // see if static class implements all of id's protocols, directly or
5137      // through its super class and categories.
5138      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5139           E = rhsOPT->qual_end(); J != E; ++J) {
5140        ObjCProtocolDecl *rhsProto = *J;
5141        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5142            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5143          match = true;
5144          break;
5145        }
5146      }
5147      // If the RHS is a qualified interface pointer "NSString<P>*",
5148      // make sure we check the class hierarchy.
5149      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5150        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5151             E = lhsQID->qual_end(); I != E; ++I) {
5152          // when comparing an id<P> on lhs with a static type on rhs,
5153          // see if static class implements all of id's protocols, directly or
5154          // through its super class and categories.
5155          if (rhsID->ClassImplementsProtocol(*I, true)) {
5156            match = true;
5157            break;
5158          }
5159        }
5160      }
5161      if (!match)
5162        return false;
5163    }
5164
5165    return true;
5166  }
5167
5168  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
5169  assert(rhsQID && "One of the LHS/RHS should be id<x>");
5170
5171  if (const ObjCObjectPointerType *lhsOPT =
5172        lhs->getAsObjCInterfacePointerType()) {
5173    // If both the right and left sides have qualifiers.
5174    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
5175         E = lhsOPT->qual_end(); I != E; ++I) {
5176      ObjCProtocolDecl *lhsProto = *I;
5177      bool match = false;
5178
5179      // when comparing an id<P> on rhs with a static type on lhs,
5180      // see if static class implements all of id's protocols, directly or
5181      // through its super class and categories.
5182      // First, lhs protocols in the qualifier list must be found, direct
5183      // or indirect in rhs's qualifier list or it is a mismatch.
5184      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5185           E = rhsQID->qual_end(); J != E; ++J) {
5186        ObjCProtocolDecl *rhsProto = *J;
5187        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5188            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5189          match = true;
5190          break;
5191        }
5192      }
5193      if (!match)
5194        return false;
5195    }
5196
5197    // Static class's protocols, or its super class or category protocols
5198    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
5199    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
5200      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5201      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
5202      // This is rather dubious but matches gcc's behavior. If lhs has
5203      // no type qualifier and its class has no static protocol(s)
5204      // assume that it is mismatch.
5205      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
5206        return false;
5207      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5208           LHSInheritedProtocols.begin(),
5209           E = LHSInheritedProtocols.end(); I != E; ++I) {
5210        bool match = false;
5211        ObjCProtocolDecl *lhsProto = (*I);
5212        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5213             E = rhsQID->qual_end(); J != E; ++J) {
5214          ObjCProtocolDecl *rhsProto = *J;
5215          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5216              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5217            match = true;
5218            break;
5219          }
5220        }
5221        if (!match)
5222          return false;
5223      }
5224    }
5225    return true;
5226  }
5227  return false;
5228}
5229
5230/// canAssignObjCInterfaces - Return true if the two interface types are
5231/// compatible for assignment from RHS to LHS.  This handles validation of any
5232/// protocol qualifiers on the LHS or RHS.
5233///
5234bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
5235                                         const ObjCObjectPointerType *RHSOPT) {
5236  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5237  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5238
5239  // If either type represents the built-in 'id' or 'Class' types, return true.
5240  if (LHS->isObjCUnqualifiedIdOrClass() ||
5241      RHS->isObjCUnqualifiedIdOrClass())
5242    return true;
5243
5244  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
5245    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5246                                             QualType(RHSOPT,0),
5247                                             false);
5248
5249  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
5250    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
5251                                                QualType(RHSOPT,0));
5252
5253  // If we have 2 user-defined types, fall into that path.
5254  if (LHS->getInterface() && RHS->getInterface())
5255    return canAssignObjCInterfaces(LHS, RHS);
5256
5257  return false;
5258}
5259
5260/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
5261/// for providing type-safety for objective-c pointers used to pass/return
5262/// arguments in block literals. When passed as arguments, passing 'A*' where
5263/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
5264/// not OK. For the return type, the opposite is not OK.
5265bool ASTContext::canAssignObjCInterfacesInBlockPointer(
5266                                         const ObjCObjectPointerType *LHSOPT,
5267                                         const ObjCObjectPointerType *RHSOPT,
5268                                         bool BlockReturnType) {
5269  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
5270    return true;
5271
5272  if (LHSOPT->isObjCBuiltinType()) {
5273    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
5274  }
5275
5276  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
5277    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5278                                             QualType(RHSOPT,0),
5279                                             false);
5280
5281  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
5282  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
5283  if (LHS && RHS)  { // We have 2 user-defined types.
5284    if (LHS != RHS) {
5285      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
5286        return BlockReturnType;
5287      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
5288        return !BlockReturnType;
5289    }
5290    else
5291      return true;
5292  }
5293  return false;
5294}
5295
5296/// getIntersectionOfProtocols - This routine finds the intersection of set
5297/// of protocols inherited from two distinct objective-c pointer objects.
5298/// It is used to build composite qualifier list of the composite type of
5299/// the conditional expression involving two objective-c pointer objects.
5300static
5301void getIntersectionOfProtocols(ASTContext &Context,
5302                                const ObjCObjectPointerType *LHSOPT,
5303                                const ObjCObjectPointerType *RHSOPT,
5304      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
5305
5306  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5307  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5308  assert(LHS->getInterface() && "LHS must have an interface base");
5309  assert(RHS->getInterface() && "RHS must have an interface base");
5310
5311  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
5312  unsigned LHSNumProtocols = LHS->getNumProtocols();
5313  if (LHSNumProtocols > 0)
5314    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
5315  else {
5316    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5317    Context.CollectInheritedProtocols(LHS->getInterface(),
5318                                      LHSInheritedProtocols);
5319    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
5320                                LHSInheritedProtocols.end());
5321  }
5322
5323  unsigned RHSNumProtocols = RHS->getNumProtocols();
5324  if (RHSNumProtocols > 0) {
5325    ObjCProtocolDecl **RHSProtocols =
5326      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
5327    for (unsigned i = 0; i < RHSNumProtocols; ++i)
5328      if (InheritedProtocolSet.count(RHSProtocols[i]))
5329        IntersectionOfProtocols.push_back(RHSProtocols[i]);
5330  } else {
5331    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
5332    Context.CollectInheritedProtocols(RHS->getInterface(),
5333                                      RHSInheritedProtocols);
5334    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5335         RHSInheritedProtocols.begin(),
5336         E = RHSInheritedProtocols.end(); I != E; ++I)
5337      if (InheritedProtocolSet.count((*I)))
5338        IntersectionOfProtocols.push_back((*I));
5339  }
5340}
5341
5342/// areCommonBaseCompatible - Returns common base class of the two classes if
5343/// one found. Note that this is O'2 algorithm. But it will be called as the
5344/// last type comparison in a ?-exp of ObjC pointer types before a
5345/// warning is issued. So, its invokation is extremely rare.
5346QualType ASTContext::areCommonBaseCompatible(
5347                                          const ObjCObjectPointerType *Lptr,
5348                                          const ObjCObjectPointerType *Rptr) {
5349  const ObjCObjectType *LHS = Lptr->getObjectType();
5350  const ObjCObjectType *RHS = Rptr->getObjectType();
5351  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
5352  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
5353  if (!LDecl || !RDecl || (LDecl == RDecl))
5354    return QualType();
5355
5356  do {
5357    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
5358    if (canAssignObjCInterfaces(LHS, RHS)) {
5359      SmallVector<ObjCProtocolDecl *, 8> Protocols;
5360      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
5361
5362      QualType Result = QualType(LHS, 0);
5363      if (!Protocols.empty())
5364        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
5365      Result = getObjCObjectPointerType(Result);
5366      return Result;
5367    }
5368  } while ((LDecl = LDecl->getSuperClass()));
5369
5370  return QualType();
5371}
5372
5373bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
5374                                         const ObjCObjectType *RHS) {
5375  assert(LHS->getInterface() && "LHS is not an interface type");
5376  assert(RHS->getInterface() && "RHS is not an interface type");
5377
5378  // Verify that the base decls are compatible: the RHS must be a subclass of
5379  // the LHS.
5380  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
5381    return false;
5382
5383  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
5384  // protocol qualified at all, then we are good.
5385  if (LHS->getNumProtocols() == 0)
5386    return true;
5387
5388  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't,
5389  // more detailed analysis is required.
5390  if (RHS->getNumProtocols() == 0) {
5391    // OK, if LHS is a superclass of RHS *and*
5392    // this superclass is assignment compatible with LHS.
5393    // false otherwise.
5394    bool IsSuperClass =
5395      LHS->getInterface()->isSuperClassOf(RHS->getInterface());
5396    if (IsSuperClass) {
5397      // OK if conversion of LHS to SuperClass results in narrowing of types
5398      // ; i.e., SuperClass may implement at least one of the protocols
5399      // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
5400      // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
5401      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
5402      CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
5403      // If super class has no protocols, it is not a match.
5404      if (SuperClassInheritedProtocols.empty())
5405        return false;
5406
5407      for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5408           LHSPE = LHS->qual_end();
5409           LHSPI != LHSPE; LHSPI++) {
5410        bool SuperImplementsProtocol = false;
5411        ObjCProtocolDecl *LHSProto = (*LHSPI);
5412
5413        for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5414             SuperClassInheritedProtocols.begin(),
5415             E = SuperClassInheritedProtocols.end(); I != E; ++I) {
5416          ObjCProtocolDecl *SuperClassProto = (*I);
5417          if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
5418            SuperImplementsProtocol = true;
5419            break;
5420          }
5421        }
5422        if (!SuperImplementsProtocol)
5423          return false;
5424      }
5425      return true;
5426    }
5427    return false;
5428  }
5429
5430  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5431                                     LHSPE = LHS->qual_end();
5432       LHSPI != LHSPE; LHSPI++) {
5433    bool RHSImplementsProtocol = false;
5434
5435    // If the RHS doesn't implement the protocol on the left, the types
5436    // are incompatible.
5437    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
5438                                       RHSPE = RHS->qual_end();
5439         RHSPI != RHSPE; RHSPI++) {
5440      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
5441        RHSImplementsProtocol = true;
5442        break;
5443      }
5444    }
5445    // FIXME: For better diagnostics, consider passing back the protocol name.
5446    if (!RHSImplementsProtocol)
5447      return false;
5448  }
5449  // The RHS implements all protocols listed on the LHS.
5450  return true;
5451}
5452
5453bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
5454  // get the "pointed to" types
5455  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
5456  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
5457
5458  if (!LHSOPT || !RHSOPT)
5459    return false;
5460
5461  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
5462         canAssignObjCInterfaces(RHSOPT, LHSOPT);
5463}
5464
5465bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
5466  return canAssignObjCInterfaces(
5467                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
5468                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
5469}
5470
5471/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
5472/// both shall have the identically qualified version of a compatible type.
5473/// C99 6.2.7p1: Two types have compatible types if their types are the
5474/// same. See 6.7.[2,3,5] for additional rules.
5475bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
5476                                    bool CompareUnqualified) {
5477  if (getLangOptions().CPlusPlus)
5478    return hasSameType(LHS, RHS);
5479
5480  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
5481}
5482
5483bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
5484  return typesAreCompatible(LHS, RHS);
5485}
5486
5487bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
5488  return !mergeTypes(LHS, RHS, true).isNull();
5489}
5490
5491/// mergeTransparentUnionType - if T is a transparent union type and a member
5492/// of T is compatible with SubType, return the merged type, else return
5493/// QualType()
5494QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
5495                                               bool OfBlockPointer,
5496                                               bool Unqualified) {
5497  if (const RecordType *UT = T->getAsUnionType()) {
5498    RecordDecl *UD = UT->getDecl();
5499    if (UD->hasAttr<TransparentUnionAttr>()) {
5500      for (RecordDecl::field_iterator it = UD->field_begin(),
5501           itend = UD->field_end(); it != itend; ++it) {
5502        QualType ET = it->getType().getUnqualifiedType();
5503        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
5504        if (!MT.isNull())
5505          return MT;
5506      }
5507    }
5508  }
5509
5510  return QualType();
5511}
5512
5513/// mergeFunctionArgumentTypes - merge two types which appear as function
5514/// argument types
5515QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
5516                                                bool OfBlockPointer,
5517                                                bool Unqualified) {
5518  // GNU extension: two types are compatible if they appear as a function
5519  // argument, one of the types is a transparent union type and the other
5520  // type is compatible with a union member
5521  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
5522                                              Unqualified);
5523  if (!lmerge.isNull())
5524    return lmerge;
5525
5526  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
5527                                              Unqualified);
5528  if (!rmerge.isNull())
5529    return rmerge;
5530
5531  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
5532}
5533
5534QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
5535                                        bool OfBlockPointer,
5536                                        bool Unqualified) {
5537  const FunctionType *lbase = lhs->getAs<FunctionType>();
5538  const FunctionType *rbase = rhs->getAs<FunctionType>();
5539  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
5540  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
5541  bool allLTypes = true;
5542  bool allRTypes = true;
5543
5544  // Check return type
5545  QualType retType;
5546  if (OfBlockPointer) {
5547    QualType RHS = rbase->getResultType();
5548    QualType LHS = lbase->getResultType();
5549    bool UnqualifiedResult = Unqualified;
5550    if (!UnqualifiedResult)
5551      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
5552    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
5553  }
5554  else
5555    retType = mergeTypes(lbase->getResultType(), rbase->getResultType(), false,
5556                         Unqualified);
5557  if (retType.isNull()) return QualType();
5558
5559  if (Unqualified)
5560    retType = retType.getUnqualifiedType();
5561
5562  CanQualType LRetType = getCanonicalType(lbase->getResultType());
5563  CanQualType RRetType = getCanonicalType(rbase->getResultType());
5564  if (Unqualified) {
5565    LRetType = LRetType.getUnqualifiedType();
5566    RRetType = RRetType.getUnqualifiedType();
5567  }
5568
5569  if (getCanonicalType(retType) != LRetType)
5570    allLTypes = false;
5571  if (getCanonicalType(retType) != RRetType)
5572    allRTypes = false;
5573
5574  // FIXME: double check this
5575  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
5576  //                           rbase->getRegParmAttr() != 0 &&
5577  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
5578  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
5579  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
5580
5581  // Compatible functions must have compatible calling conventions
5582  if (!isSameCallConv(lbaseInfo.getCC(), rbaseInfo.getCC()))
5583    return QualType();
5584
5585  // Regparm is part of the calling convention.
5586  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
5587    return QualType();
5588  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
5589    return QualType();
5590
5591  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
5592    return QualType();
5593
5594  // functypes which return are preferred over those that do not.
5595  if (lbaseInfo.getNoReturn() && !rbaseInfo.getNoReturn())
5596    allLTypes = false;
5597  else if (!lbaseInfo.getNoReturn() && rbaseInfo.getNoReturn())
5598    allRTypes = false;
5599  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
5600  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
5601
5602  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
5603
5604  if (lproto && rproto) { // two C99 style function prototypes
5605    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
5606           "C++ shouldn't be here");
5607    unsigned lproto_nargs = lproto->getNumArgs();
5608    unsigned rproto_nargs = rproto->getNumArgs();
5609
5610    // Compatible functions must have the same number of arguments
5611    if (lproto_nargs != rproto_nargs)
5612      return QualType();
5613
5614    // Variadic and non-variadic functions aren't compatible
5615    if (lproto->isVariadic() != rproto->isVariadic())
5616      return QualType();
5617
5618    if (lproto->getTypeQuals() != rproto->getTypeQuals())
5619      return QualType();
5620
5621    if (LangOpts.ObjCAutoRefCount &&
5622        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
5623      return QualType();
5624
5625    // Check argument compatibility
5626    SmallVector<QualType, 10> types;
5627    for (unsigned i = 0; i < lproto_nargs; i++) {
5628      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
5629      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
5630      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
5631                                                    OfBlockPointer,
5632                                                    Unqualified);
5633      if (argtype.isNull()) return QualType();
5634
5635      if (Unqualified)
5636        argtype = argtype.getUnqualifiedType();
5637
5638      types.push_back(argtype);
5639      if (Unqualified) {
5640        largtype = largtype.getUnqualifiedType();
5641        rargtype = rargtype.getUnqualifiedType();
5642      }
5643
5644      if (getCanonicalType(argtype) != getCanonicalType(largtype))
5645        allLTypes = false;
5646      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
5647        allRTypes = false;
5648    }
5649
5650    if (allLTypes) return lhs;
5651    if (allRTypes) return rhs;
5652
5653    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
5654    EPI.ExtInfo = einfo;
5655    return getFunctionType(retType, types.begin(), types.size(), EPI);
5656  }
5657
5658  if (lproto) allRTypes = false;
5659  if (rproto) allLTypes = false;
5660
5661  const FunctionProtoType *proto = lproto ? lproto : rproto;
5662  if (proto) {
5663    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
5664    if (proto->isVariadic()) return QualType();
5665    // Check that the types are compatible with the types that
5666    // would result from default argument promotions (C99 6.7.5.3p15).
5667    // The only types actually affected are promotable integer
5668    // types and floats, which would be passed as a different
5669    // type depending on whether the prototype is visible.
5670    unsigned proto_nargs = proto->getNumArgs();
5671    for (unsigned i = 0; i < proto_nargs; ++i) {
5672      QualType argTy = proto->getArgType(i);
5673
5674      // Look at the promotion type of enum types, since that is the type used
5675      // to pass enum values.
5676      if (const EnumType *Enum = argTy->getAs<EnumType>())
5677        argTy = Enum->getDecl()->getPromotionType();
5678
5679      if (argTy->isPromotableIntegerType() ||
5680          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
5681        return QualType();
5682    }
5683
5684    if (allLTypes) return lhs;
5685    if (allRTypes) return rhs;
5686
5687    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
5688    EPI.ExtInfo = einfo;
5689    return getFunctionType(retType, proto->arg_type_begin(),
5690                           proto->getNumArgs(), EPI);
5691  }
5692
5693  if (allLTypes) return lhs;
5694  if (allRTypes) return rhs;
5695  return getFunctionNoProtoType(retType, einfo);
5696}
5697
5698QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
5699                                bool OfBlockPointer,
5700                                bool Unqualified, bool BlockReturnType) {
5701  // C++ [expr]: If an expression initially has the type "reference to T", the
5702  // type is adjusted to "T" prior to any further analysis, the expression
5703  // designates the object or function denoted by the reference, and the
5704  // expression is an lvalue unless the reference is an rvalue reference and
5705  // the expression is a function call (possibly inside parentheses).
5706  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
5707  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
5708
5709  if (Unqualified) {
5710    LHS = LHS.getUnqualifiedType();
5711    RHS = RHS.getUnqualifiedType();
5712  }
5713
5714  QualType LHSCan = getCanonicalType(LHS),
5715           RHSCan = getCanonicalType(RHS);
5716
5717  // If two types are identical, they are compatible.
5718  if (LHSCan == RHSCan)
5719    return LHS;
5720
5721  // If the qualifiers are different, the types aren't compatible... mostly.
5722  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5723  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5724  if (LQuals != RQuals) {
5725    // If any of these qualifiers are different, we have a type
5726    // mismatch.
5727    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5728        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
5729        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
5730      return QualType();
5731
5732    // Exactly one GC qualifier difference is allowed: __strong is
5733    // okay if the other type has no GC qualifier but is an Objective
5734    // C object pointer (i.e. implicitly strong by default).  We fix
5735    // this by pretending that the unqualified type was actually
5736    // qualified __strong.
5737    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5738    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5739    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5740
5741    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5742      return QualType();
5743
5744    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
5745      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
5746    }
5747    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
5748      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
5749    }
5750    return QualType();
5751  }
5752
5753  // Okay, qualifiers are equal.
5754
5755  Type::TypeClass LHSClass = LHSCan->getTypeClass();
5756  Type::TypeClass RHSClass = RHSCan->getTypeClass();
5757
5758  // We want to consider the two function types to be the same for these
5759  // comparisons, just force one to the other.
5760  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
5761  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
5762
5763  // Same as above for arrays
5764  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
5765    LHSClass = Type::ConstantArray;
5766  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
5767    RHSClass = Type::ConstantArray;
5768
5769  // ObjCInterfaces are just specialized ObjCObjects.
5770  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
5771  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
5772
5773  // Canonicalize ExtVector -> Vector.
5774  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
5775  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
5776
5777  // If the canonical type classes don't match.
5778  if (LHSClass != RHSClass) {
5779    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
5780    // a signed integer type, or an unsigned integer type.
5781    // Compatibility is based on the underlying type, not the promotion
5782    // type.
5783    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
5784      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
5785        return RHS;
5786    }
5787    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
5788      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
5789        return LHS;
5790    }
5791
5792    return QualType();
5793  }
5794
5795  // The canonical type classes match.
5796  switch (LHSClass) {
5797#define TYPE(Class, Base)
5798#define ABSTRACT_TYPE(Class, Base)
5799#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
5800#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
5801#define DEPENDENT_TYPE(Class, Base) case Type::Class:
5802#include "clang/AST/TypeNodes.def"
5803    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
5804
5805  case Type::LValueReference:
5806  case Type::RValueReference:
5807  case Type::MemberPointer:
5808    llvm_unreachable("C++ should never be in mergeTypes");
5809
5810  case Type::ObjCInterface:
5811  case Type::IncompleteArray:
5812  case Type::VariableArray:
5813  case Type::FunctionProto:
5814  case Type::ExtVector:
5815    llvm_unreachable("Types are eliminated above");
5816
5817  case Type::Pointer:
5818  {
5819    // Merge two pointer types, while trying to preserve typedef info
5820    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
5821    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
5822    if (Unqualified) {
5823      LHSPointee = LHSPointee.getUnqualifiedType();
5824      RHSPointee = RHSPointee.getUnqualifiedType();
5825    }
5826    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
5827                                     Unqualified);
5828    if (ResultType.isNull()) return QualType();
5829    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5830      return LHS;
5831    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5832      return RHS;
5833    return getPointerType(ResultType);
5834  }
5835  case Type::BlockPointer:
5836  {
5837    // Merge two block pointer types, while trying to preserve typedef info
5838    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
5839    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
5840    if (Unqualified) {
5841      LHSPointee = LHSPointee.getUnqualifiedType();
5842      RHSPointee = RHSPointee.getUnqualifiedType();
5843    }
5844    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
5845                                     Unqualified);
5846    if (ResultType.isNull()) return QualType();
5847    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5848      return LHS;
5849    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5850      return RHS;
5851    return getBlockPointerType(ResultType);
5852  }
5853  case Type::Atomic:
5854  {
5855    // Merge two pointer types, while trying to preserve typedef info
5856    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
5857    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
5858    if (Unqualified) {
5859      LHSValue = LHSValue.getUnqualifiedType();
5860      RHSValue = RHSValue.getUnqualifiedType();
5861    }
5862    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
5863                                     Unqualified);
5864    if (ResultType.isNull()) return QualType();
5865    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
5866      return LHS;
5867    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
5868      return RHS;
5869    return getAtomicType(ResultType);
5870  }
5871  case Type::ConstantArray:
5872  {
5873    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
5874    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
5875    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
5876      return QualType();
5877
5878    QualType LHSElem = getAsArrayType(LHS)->getElementType();
5879    QualType RHSElem = getAsArrayType(RHS)->getElementType();
5880    if (Unqualified) {
5881      LHSElem = LHSElem.getUnqualifiedType();
5882      RHSElem = RHSElem.getUnqualifiedType();
5883    }
5884
5885    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
5886    if (ResultType.isNull()) return QualType();
5887    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5888      return LHS;
5889    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5890      return RHS;
5891    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
5892                                          ArrayType::ArraySizeModifier(), 0);
5893    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
5894                                          ArrayType::ArraySizeModifier(), 0);
5895    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
5896    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
5897    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5898      return LHS;
5899    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5900      return RHS;
5901    if (LVAT) {
5902      // FIXME: This isn't correct! But tricky to implement because
5903      // the array's size has to be the size of LHS, but the type
5904      // has to be different.
5905      return LHS;
5906    }
5907    if (RVAT) {
5908      // FIXME: This isn't correct! But tricky to implement because
5909      // the array's size has to be the size of RHS, but the type
5910      // has to be different.
5911      return RHS;
5912    }
5913    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
5914    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
5915    return getIncompleteArrayType(ResultType,
5916                                  ArrayType::ArraySizeModifier(), 0);
5917  }
5918  case Type::FunctionNoProto:
5919    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
5920  case Type::Record:
5921  case Type::Enum:
5922    return QualType();
5923  case Type::Builtin:
5924    // Only exactly equal builtin types are compatible, which is tested above.
5925    return QualType();
5926  case Type::Complex:
5927    // Distinct complex types are incompatible.
5928    return QualType();
5929  case Type::Vector:
5930    // FIXME: The merged type should be an ExtVector!
5931    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
5932                             RHSCan->getAs<VectorType>()))
5933      return LHS;
5934    return QualType();
5935  case Type::ObjCObject: {
5936    // Check if the types are assignment compatible.
5937    // FIXME: This should be type compatibility, e.g. whether
5938    // "LHS x; RHS x;" at global scope is legal.
5939    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
5940    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
5941    if (canAssignObjCInterfaces(LHSIface, RHSIface))
5942      return LHS;
5943
5944    return QualType();
5945  }
5946  case Type::ObjCObjectPointer: {
5947    if (OfBlockPointer) {
5948      if (canAssignObjCInterfacesInBlockPointer(
5949                                          LHS->getAs<ObjCObjectPointerType>(),
5950                                          RHS->getAs<ObjCObjectPointerType>(),
5951                                          BlockReturnType))
5952      return LHS;
5953      return QualType();
5954    }
5955    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
5956                                RHS->getAs<ObjCObjectPointerType>()))
5957      return LHS;
5958
5959    return QualType();
5960    }
5961  }
5962
5963  return QualType();
5964}
5965
5966bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
5967                   const FunctionProtoType *FromFunctionType,
5968                   const FunctionProtoType *ToFunctionType) {
5969  if (FromFunctionType->hasAnyConsumedArgs() !=
5970      ToFunctionType->hasAnyConsumedArgs())
5971    return false;
5972  FunctionProtoType::ExtProtoInfo FromEPI =
5973    FromFunctionType->getExtProtoInfo();
5974  FunctionProtoType::ExtProtoInfo ToEPI =
5975    ToFunctionType->getExtProtoInfo();
5976  if (FromEPI.ConsumedArguments && ToEPI.ConsumedArguments)
5977    for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs();
5978         ArgIdx != NumArgs; ++ArgIdx)  {
5979      if (FromEPI.ConsumedArguments[ArgIdx] !=
5980          ToEPI.ConsumedArguments[ArgIdx])
5981        return false;
5982    }
5983  return true;
5984}
5985
5986/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
5987/// 'RHS' attributes and returns the merged version; including for function
5988/// return types.
5989QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
5990  QualType LHSCan = getCanonicalType(LHS),
5991  RHSCan = getCanonicalType(RHS);
5992  // If two types are identical, they are compatible.
5993  if (LHSCan == RHSCan)
5994    return LHS;
5995  if (RHSCan->isFunctionType()) {
5996    if (!LHSCan->isFunctionType())
5997      return QualType();
5998    QualType OldReturnType =
5999      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
6000    QualType NewReturnType =
6001      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
6002    QualType ResReturnType =
6003      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
6004    if (ResReturnType.isNull())
6005      return QualType();
6006    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
6007      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
6008      // In either case, use OldReturnType to build the new function type.
6009      const FunctionType *F = LHS->getAs<FunctionType>();
6010      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
6011        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
6012        EPI.ExtInfo = getFunctionExtInfo(LHS);
6013        QualType ResultType
6014          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
6015                            FPT->getNumArgs(), EPI);
6016        return ResultType;
6017      }
6018    }
6019    return QualType();
6020  }
6021
6022  // If the qualifiers are different, the types can still be merged.
6023  Qualifiers LQuals = LHSCan.getLocalQualifiers();
6024  Qualifiers RQuals = RHSCan.getLocalQualifiers();
6025  if (LQuals != RQuals) {
6026    // If any of these qualifiers are different, we have a type mismatch.
6027    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
6028        LQuals.getAddressSpace() != RQuals.getAddressSpace())
6029      return QualType();
6030
6031    // Exactly one GC qualifier difference is allowed: __strong is
6032    // okay if the other type has no GC qualifier but is an Objective
6033    // C object pointer (i.e. implicitly strong by default).  We fix
6034    // this by pretending that the unqualified type was actually
6035    // qualified __strong.
6036    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
6037    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
6038    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
6039
6040    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
6041      return QualType();
6042
6043    if (GC_L == Qualifiers::Strong)
6044      return LHS;
6045    if (GC_R == Qualifiers::Strong)
6046      return RHS;
6047    return QualType();
6048  }
6049
6050  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
6051    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6052    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6053    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
6054    if (ResQT == LHSBaseQT)
6055      return LHS;
6056    if (ResQT == RHSBaseQT)
6057      return RHS;
6058  }
6059  return QualType();
6060}
6061
6062//===----------------------------------------------------------------------===//
6063//                         Integer Predicates
6064//===----------------------------------------------------------------------===//
6065
6066unsigned ASTContext::getIntWidth(QualType T) const {
6067  if (const EnumType *ET = dyn_cast<EnumType>(T))
6068    T = ET->getDecl()->getIntegerType();
6069  if (T->isBooleanType())
6070    return 1;
6071  // For builtin types, just use the standard type sizing method
6072  return (unsigned)getTypeSize(T);
6073}
6074
6075QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
6076  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
6077
6078  // Turn <4 x signed int> -> <4 x unsigned int>
6079  if (const VectorType *VTy = T->getAs<VectorType>())
6080    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
6081                         VTy->getNumElements(), VTy->getVectorKind());
6082
6083  // For enums, we return the unsigned version of the base type.
6084  if (const EnumType *ETy = T->getAs<EnumType>())
6085    T = ETy->getDecl()->getIntegerType();
6086
6087  const BuiltinType *BTy = T->getAs<BuiltinType>();
6088  assert(BTy && "Unexpected signed integer type");
6089  switch (BTy->getKind()) {
6090  case BuiltinType::Char_S:
6091  case BuiltinType::SChar:
6092    return UnsignedCharTy;
6093  case BuiltinType::Short:
6094    return UnsignedShortTy;
6095  case BuiltinType::Int:
6096    return UnsignedIntTy;
6097  case BuiltinType::Long:
6098    return UnsignedLongTy;
6099  case BuiltinType::LongLong:
6100    return UnsignedLongLongTy;
6101  case BuiltinType::Int128:
6102    return UnsignedInt128Ty;
6103  default:
6104    llvm_unreachable("Unexpected signed integer type");
6105  }
6106}
6107
6108ASTMutationListener::~ASTMutationListener() { }
6109
6110
6111//===----------------------------------------------------------------------===//
6112//                          Builtin Type Computation
6113//===----------------------------------------------------------------------===//
6114
6115/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
6116/// pointer over the consumed characters.  This returns the resultant type.  If
6117/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
6118/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
6119/// a vector of "i*".
6120///
6121/// RequiresICE is filled in on return to indicate whether the value is required
6122/// to be an Integer Constant Expression.
6123static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
6124                                  ASTContext::GetBuiltinTypeError &Error,
6125                                  bool &RequiresICE,
6126                                  bool AllowTypeModifiers) {
6127  // Modifiers.
6128  int HowLong = 0;
6129  bool Signed = false, Unsigned = false;
6130  RequiresICE = false;
6131
6132  // Read the prefixed modifiers first.
6133  bool Done = false;
6134  while (!Done) {
6135    switch (*Str++) {
6136    default: Done = true; --Str; break;
6137    case 'I':
6138      RequiresICE = true;
6139      break;
6140    case 'S':
6141      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
6142      assert(!Signed && "Can't use 'S' modifier multiple times!");
6143      Signed = true;
6144      break;
6145    case 'U':
6146      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
6147      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
6148      Unsigned = true;
6149      break;
6150    case 'L':
6151      assert(HowLong <= 2 && "Can't have LLLL modifier");
6152      ++HowLong;
6153      break;
6154    }
6155  }
6156
6157  QualType Type;
6158
6159  // Read the base type.
6160  switch (*Str++) {
6161  default: llvm_unreachable("Unknown builtin type letter!");
6162  case 'v':
6163    assert(HowLong == 0 && !Signed && !Unsigned &&
6164           "Bad modifiers used with 'v'!");
6165    Type = Context.VoidTy;
6166    break;
6167  case 'f':
6168    assert(HowLong == 0 && !Signed && !Unsigned &&
6169           "Bad modifiers used with 'f'!");
6170    Type = Context.FloatTy;
6171    break;
6172  case 'd':
6173    assert(HowLong < 2 && !Signed && !Unsigned &&
6174           "Bad modifiers used with 'd'!");
6175    if (HowLong)
6176      Type = Context.LongDoubleTy;
6177    else
6178      Type = Context.DoubleTy;
6179    break;
6180  case 's':
6181    assert(HowLong == 0 && "Bad modifiers used with 's'!");
6182    if (Unsigned)
6183      Type = Context.UnsignedShortTy;
6184    else
6185      Type = Context.ShortTy;
6186    break;
6187  case 'i':
6188    if (HowLong == 3)
6189      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
6190    else if (HowLong == 2)
6191      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
6192    else if (HowLong == 1)
6193      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
6194    else
6195      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
6196    break;
6197  case 'c':
6198    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
6199    if (Signed)
6200      Type = Context.SignedCharTy;
6201    else if (Unsigned)
6202      Type = Context.UnsignedCharTy;
6203    else
6204      Type = Context.CharTy;
6205    break;
6206  case 'b': // boolean
6207    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
6208    Type = Context.BoolTy;
6209    break;
6210  case 'z':  // size_t.
6211    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
6212    Type = Context.getSizeType();
6213    break;
6214  case 'F':
6215    Type = Context.getCFConstantStringType();
6216    break;
6217  case 'G':
6218    Type = Context.getObjCIdType();
6219    break;
6220  case 'H':
6221    Type = Context.getObjCSelType();
6222    break;
6223  case 'a':
6224    Type = Context.getBuiltinVaListType();
6225    assert(!Type.isNull() && "builtin va list type not initialized!");
6226    break;
6227  case 'A':
6228    // This is a "reference" to a va_list; however, what exactly
6229    // this means depends on how va_list is defined. There are two
6230    // different kinds of va_list: ones passed by value, and ones
6231    // passed by reference.  An example of a by-value va_list is
6232    // x86, where va_list is a char*. An example of by-ref va_list
6233    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
6234    // we want this argument to be a char*&; for x86-64, we want
6235    // it to be a __va_list_tag*.
6236    Type = Context.getBuiltinVaListType();
6237    assert(!Type.isNull() && "builtin va list type not initialized!");
6238    if (Type->isArrayType())
6239      Type = Context.getArrayDecayedType(Type);
6240    else
6241      Type = Context.getLValueReferenceType(Type);
6242    break;
6243  case 'V': {
6244    char *End;
6245    unsigned NumElements = strtoul(Str, &End, 10);
6246    assert(End != Str && "Missing vector size");
6247    Str = End;
6248
6249    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
6250                                             RequiresICE, false);
6251    assert(!RequiresICE && "Can't require vector ICE");
6252
6253    // TODO: No way to make AltiVec vectors in builtins yet.
6254    Type = Context.getVectorType(ElementType, NumElements,
6255                                 VectorType::GenericVector);
6256    break;
6257  }
6258  case 'X': {
6259    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
6260                                             false);
6261    assert(!RequiresICE && "Can't require complex ICE");
6262    Type = Context.getComplexType(ElementType);
6263    break;
6264  }
6265  case 'Y' : {
6266    Type = Context.getPointerDiffType();
6267    break;
6268  }
6269  case 'P':
6270    Type = Context.getFILEType();
6271    if (Type.isNull()) {
6272      Error = ASTContext::GE_Missing_stdio;
6273      return QualType();
6274    }
6275    break;
6276  case 'J':
6277    if (Signed)
6278      Type = Context.getsigjmp_bufType();
6279    else
6280      Type = Context.getjmp_bufType();
6281
6282    if (Type.isNull()) {
6283      Error = ASTContext::GE_Missing_setjmp;
6284      return QualType();
6285    }
6286    break;
6287  }
6288
6289  // If there are modifiers and if we're allowed to parse them, go for it.
6290  Done = !AllowTypeModifiers;
6291  while (!Done) {
6292    switch (char c = *Str++) {
6293    default: Done = true; --Str; break;
6294    case '*':
6295    case '&': {
6296      // Both pointers and references can have their pointee types
6297      // qualified with an address space.
6298      char *End;
6299      unsigned AddrSpace = strtoul(Str, &End, 10);
6300      if (End != Str && AddrSpace != 0) {
6301        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
6302        Str = End;
6303      }
6304      if (c == '*')
6305        Type = Context.getPointerType(Type);
6306      else
6307        Type = Context.getLValueReferenceType(Type);
6308      break;
6309    }
6310    // FIXME: There's no way to have a built-in with an rvalue ref arg.
6311    case 'C':
6312      Type = Type.withConst();
6313      break;
6314    case 'D':
6315      Type = Context.getVolatileType(Type);
6316      break;
6317    }
6318  }
6319
6320  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
6321         "Integer constant 'I' type must be an integer");
6322
6323  return Type;
6324}
6325
6326/// GetBuiltinType - Return the type for the specified builtin.
6327QualType ASTContext::GetBuiltinType(unsigned Id,
6328                                    GetBuiltinTypeError &Error,
6329                                    unsigned *IntegerConstantArgs) const {
6330  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
6331
6332  SmallVector<QualType, 8> ArgTypes;
6333
6334  bool RequiresICE = false;
6335  Error = GE_None;
6336  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
6337                                       RequiresICE, true);
6338  if (Error != GE_None)
6339    return QualType();
6340
6341  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
6342
6343  while (TypeStr[0] && TypeStr[0] != '.') {
6344    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
6345    if (Error != GE_None)
6346      return QualType();
6347
6348    // If this argument is required to be an IntegerConstantExpression and the
6349    // caller cares, fill in the bitmask we return.
6350    if (RequiresICE && IntegerConstantArgs)
6351      *IntegerConstantArgs |= 1 << ArgTypes.size();
6352
6353    // Do array -> pointer decay.  The builtin should use the decayed type.
6354    if (Ty->isArrayType())
6355      Ty = getArrayDecayedType(Ty);
6356
6357    ArgTypes.push_back(Ty);
6358  }
6359
6360  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
6361         "'.' should only occur at end of builtin type list!");
6362
6363  FunctionType::ExtInfo EI;
6364  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
6365
6366  bool Variadic = (TypeStr[0] == '.');
6367
6368  // We really shouldn't be making a no-proto type here, especially in C++.
6369  if (ArgTypes.empty() && Variadic)
6370    return getFunctionNoProtoType(ResType, EI);
6371
6372  FunctionProtoType::ExtProtoInfo EPI;
6373  EPI.ExtInfo = EI;
6374  EPI.Variadic = Variadic;
6375
6376  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(), EPI);
6377}
6378
6379GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
6380  GVALinkage External = GVA_StrongExternal;
6381
6382  Linkage L = FD->getLinkage();
6383  switch (L) {
6384  case NoLinkage:
6385  case InternalLinkage:
6386  case UniqueExternalLinkage:
6387    return GVA_Internal;
6388
6389  case ExternalLinkage:
6390    switch (FD->getTemplateSpecializationKind()) {
6391    case TSK_Undeclared:
6392    case TSK_ExplicitSpecialization:
6393      External = GVA_StrongExternal;
6394      break;
6395
6396    case TSK_ExplicitInstantiationDefinition:
6397      return GVA_ExplicitTemplateInstantiation;
6398
6399    case TSK_ExplicitInstantiationDeclaration:
6400    case TSK_ImplicitInstantiation:
6401      External = GVA_TemplateInstantiation;
6402      break;
6403    }
6404  }
6405
6406  if (!FD->isInlined())
6407    return External;
6408
6409  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
6410    // GNU or C99 inline semantics. Determine whether this symbol should be
6411    // externally visible.
6412    if (FD->isInlineDefinitionExternallyVisible())
6413      return External;
6414
6415    // C99 inline semantics, where the symbol is not externally visible.
6416    return GVA_C99Inline;
6417  }
6418
6419  // C++0x [temp.explicit]p9:
6420  //   [ Note: The intent is that an inline function that is the subject of
6421  //   an explicit instantiation declaration will still be implicitly
6422  //   instantiated when used so that the body can be considered for
6423  //   inlining, but that no out-of-line copy of the inline function would be
6424  //   generated in the translation unit. -- end note ]
6425  if (FD->getTemplateSpecializationKind()
6426                                       == TSK_ExplicitInstantiationDeclaration)
6427    return GVA_C99Inline;
6428
6429  return GVA_CXXInline;
6430}
6431
6432GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
6433  // If this is a static data member, compute the kind of template
6434  // specialization. Otherwise, this variable is not part of a
6435  // template.
6436  TemplateSpecializationKind TSK = TSK_Undeclared;
6437  if (VD->isStaticDataMember())
6438    TSK = VD->getTemplateSpecializationKind();
6439
6440  Linkage L = VD->getLinkage();
6441  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
6442      VD->getType()->getLinkage() == UniqueExternalLinkage)
6443    L = UniqueExternalLinkage;
6444
6445  switch (L) {
6446  case NoLinkage:
6447  case InternalLinkage:
6448  case UniqueExternalLinkage:
6449    return GVA_Internal;
6450
6451  case ExternalLinkage:
6452    switch (TSK) {
6453    case TSK_Undeclared:
6454    case TSK_ExplicitSpecialization:
6455      return GVA_StrongExternal;
6456
6457    case TSK_ExplicitInstantiationDeclaration:
6458      llvm_unreachable("Variable should not be instantiated");
6459      // Fall through to treat this like any other instantiation.
6460
6461    case TSK_ExplicitInstantiationDefinition:
6462      return GVA_ExplicitTemplateInstantiation;
6463
6464    case TSK_ImplicitInstantiation:
6465      return GVA_TemplateInstantiation;
6466    }
6467  }
6468
6469  return GVA_StrongExternal;
6470}
6471
6472bool ASTContext::DeclMustBeEmitted(const Decl *D) {
6473  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
6474    if (!VD->isFileVarDecl())
6475      return false;
6476  } else if (!isa<FunctionDecl>(D))
6477    return false;
6478
6479  // Weak references don't produce any output by themselves.
6480  if (D->hasAttr<WeakRefAttr>())
6481    return false;
6482
6483  // Aliases and used decls are required.
6484  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
6485    return true;
6486
6487  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
6488    // Forward declarations aren't required.
6489    if (!FD->doesThisDeclarationHaveABody())
6490      return FD->doesDeclarationForceExternallyVisibleDefinition();
6491
6492    // Constructors and destructors are required.
6493    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
6494      return true;
6495
6496    // The key function for a class is required.
6497    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
6498      const CXXRecordDecl *RD = MD->getParent();
6499      if (MD->isOutOfLine() && RD->isDynamicClass()) {
6500        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
6501        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
6502          return true;
6503      }
6504    }
6505
6506    GVALinkage Linkage = GetGVALinkageForFunction(FD);
6507
6508    // static, static inline, always_inline, and extern inline functions can
6509    // always be deferred.  Normal inline functions can be deferred in C99/C++.
6510    // Implicit template instantiations can also be deferred in C++.
6511    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
6512        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
6513      return false;
6514    return true;
6515  }
6516
6517  const VarDecl *VD = cast<VarDecl>(D);
6518  assert(VD->isFileVarDecl() && "Expected file scoped var");
6519
6520  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
6521    return false;
6522
6523  // Structs that have non-trivial constructors or destructors are required.
6524
6525  // FIXME: Handle references.
6526  // FIXME: Be more selective about which constructors we care about.
6527  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
6528    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
6529      if (RD->hasDefinition() && !(RD->hasTrivialDefaultConstructor() &&
6530                                   RD->hasTrivialCopyConstructor() &&
6531                                   RD->hasTrivialMoveConstructor() &&
6532                                   RD->hasTrivialDestructor()))
6533        return true;
6534    }
6535  }
6536
6537  GVALinkage L = GetGVALinkageForVariable(VD);
6538  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
6539    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
6540      return false;
6541  }
6542
6543  return true;
6544}
6545
6546CallingConv ASTContext::getDefaultMethodCallConv() {
6547  // Pass through to the C++ ABI object
6548  return ABI->getDefaultMethodCallConv();
6549}
6550
6551bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
6552  // Pass through to the C++ ABI object
6553  return ABI->isNearlyEmpty(RD);
6554}
6555
6556MangleContext *ASTContext::createMangleContext() {
6557  switch (Target->getCXXABI()) {
6558  case CXXABI_ARM:
6559  case CXXABI_Itanium:
6560    return createItaniumMangleContext(*this, getDiagnostics());
6561  case CXXABI_Microsoft:
6562    return createMicrosoftMangleContext(*this, getDiagnostics());
6563  }
6564  llvm_unreachable("Unsupported ABI");
6565}
6566
6567CXXABI::~CXXABI() {}
6568
6569size_t ASTContext::getSideTableAllocatedMemory() const {
6570  return ASTRecordLayouts.getMemorySize()
6571    + llvm::capacity_in_bytes(ObjCLayouts)
6572    + llvm::capacity_in_bytes(KeyFunctions)
6573    + llvm::capacity_in_bytes(ObjCImpls)
6574    + llvm::capacity_in_bytes(BlockVarCopyInits)
6575    + llvm::capacity_in_bytes(DeclAttrs)
6576    + llvm::capacity_in_bytes(InstantiatedFromStaticDataMember)
6577    + llvm::capacity_in_bytes(InstantiatedFromUsingDecl)
6578    + llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl)
6579    + llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl)
6580    + llvm::capacity_in_bytes(OverriddenMethods)
6581    + llvm::capacity_in_bytes(Types)
6582    + llvm::capacity_in_bytes(VariableArrayTypes)
6583    + llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
6584}
6585
6586void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
6587  ParamIndices[D] = index;
6588}
6589
6590unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
6591  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
6592  assert(I != ParamIndices.end() &&
6593         "ParmIndices lacks entry set by ParmVarDecl");
6594  return I->second;
6595}
6596