ASTContext.cpp revision b001de7458d17c17e6d8b8034c7cfcefd3b70c00 
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->getBitWidth()->EvaluateAsInt(*this).getZExtValue() == 0);
612}
613
614bool ASTContext::ZeroBitfieldFollowsBitfield(const FieldDecl *FD,
615                                             const FieldDecl *LastFD) const {
616  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
617          FD->getBitWidth()->EvaluateAsInt(*this).getZExtValue() == 0 &&
618          LastFD->getBitWidth()->EvaluateAsInt(*this).getZExtValue() != 0);
619}
620
621bool ASTContext::BitfieldFollowsBitfield(const FieldDecl *FD,
622                                         const FieldDecl *LastFD) const {
623  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
624          FD->getBitWidth()->EvaluateAsInt(*this).getZExtValue() &&
625          LastFD->getBitWidth()->EvaluateAsInt(*this).getZExtValue());
626}
627
628bool ASTContext::NonBitfieldFollowsBitfield(const FieldDecl *FD,
629                                         const FieldDecl *LastFD) const {
630  return (!FD->isBitField() && LastFD && LastFD->isBitField() &&
631          LastFD->getBitWidth()->EvaluateAsInt(*this).getZExtValue());
632}
633
634bool ASTContext::BitfieldFollowsNonBitfield(const FieldDecl *FD,
635                                             const FieldDecl *LastFD) const {
636  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
637          FD->getBitWidth()->EvaluateAsInt(*this).getZExtValue());
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    // FIXME: The alignment needs to be "fixed".
1068    return getTypeInfo(cast<AtomicType>(T)->getValueType());
1069  }
1070
1071  }
1072
1073  assert(Align && (Align & (Align-1)) == 0 && "Alignment must be power of 2");
1074  return std::make_pair(Width, Align);
1075}
1076
1077/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1078CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1079  return CharUnits::fromQuantity(BitSize / getCharWidth());
1080}
1081
1082/// toBits - Convert a size in characters to a size in characters.
1083int64_t ASTContext::toBits(CharUnits CharSize) const {
1084  return CharSize.getQuantity() * getCharWidth();
1085}
1086
1087/// getTypeSizeInChars - Return the size of the specified type, in characters.
1088/// This method does not work on incomplete types.
1089CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1090  return toCharUnitsFromBits(getTypeSize(T));
1091}
1092CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1093  return toCharUnitsFromBits(getTypeSize(T));
1094}
1095
1096/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1097/// characters. This method does not work on incomplete types.
1098CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1099  return toCharUnitsFromBits(getTypeAlign(T));
1100}
1101CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1102  return toCharUnitsFromBits(getTypeAlign(T));
1103}
1104
1105/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1106/// type for the current target in bits.  This can be different than the ABI
1107/// alignment in cases where it is beneficial for performance to overalign
1108/// a data type.
1109unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1110  unsigned ABIAlign = getTypeAlign(T);
1111
1112  // Double and long long should be naturally aligned if possible.
1113  if (const ComplexType* CT = T->getAs<ComplexType>())
1114    T = CT->getElementType().getTypePtr();
1115  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1116      T->isSpecificBuiltinType(BuiltinType::LongLong))
1117    return std::max(ABIAlign, (unsigned)getTypeSize(T));
1118
1119  return ABIAlign;
1120}
1121
1122/// DeepCollectObjCIvars -
1123/// This routine first collects all declared, but not synthesized, ivars in
1124/// super class and then collects all ivars, including those synthesized for
1125/// current class. This routine is used for implementation of current class
1126/// when all ivars, declared and synthesized are known.
1127///
1128void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1129                                      bool leafClass,
1130                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1131  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1132    DeepCollectObjCIvars(SuperClass, false, Ivars);
1133  if (!leafClass) {
1134    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
1135         E = OI->ivar_end(); I != E; ++I)
1136      Ivars.push_back(*I);
1137  } else {
1138    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1139    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1140         Iv= Iv->getNextIvar())
1141      Ivars.push_back(Iv);
1142  }
1143}
1144
1145/// CollectInheritedProtocols - Collect all protocols in current class and
1146/// those inherited by it.
1147void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1148                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1149  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1150    // We can use protocol_iterator here instead of
1151    // all_referenced_protocol_iterator since we are walking all categories.
1152    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
1153         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
1154      ObjCProtocolDecl *Proto = (*P);
1155      Protocols.insert(Proto);
1156      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1157           PE = Proto->protocol_end(); P != PE; ++P) {
1158        Protocols.insert(*P);
1159        CollectInheritedProtocols(*P, Protocols);
1160      }
1161    }
1162
1163    // Categories of this Interface.
1164    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
1165         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
1166      CollectInheritedProtocols(CDeclChain, Protocols);
1167    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1168      while (SD) {
1169        CollectInheritedProtocols(SD, Protocols);
1170        SD = SD->getSuperClass();
1171      }
1172  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1173    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
1174         PE = OC->protocol_end(); P != PE; ++P) {
1175      ObjCProtocolDecl *Proto = (*P);
1176      Protocols.insert(Proto);
1177      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1178           PE = Proto->protocol_end(); P != PE; ++P)
1179        CollectInheritedProtocols(*P, Protocols);
1180    }
1181  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
1182    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
1183         PE = OP->protocol_end(); P != PE; ++P) {
1184      ObjCProtocolDecl *Proto = (*P);
1185      Protocols.insert(Proto);
1186      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1187           PE = Proto->protocol_end(); P != PE; ++P)
1188        CollectInheritedProtocols(*P, Protocols);
1189    }
1190  }
1191}
1192
1193unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
1194  unsigned count = 0;
1195  // Count ivars declared in class extension.
1196  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
1197       CDecl = CDecl->getNextClassExtension())
1198    count += CDecl->ivar_size();
1199
1200  // Count ivar defined in this class's implementation.  This
1201  // includes synthesized ivars.
1202  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
1203    count += ImplDecl->ivar_size();
1204
1205  return count;
1206}
1207
1208/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
1209ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
1210  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1211    I = ObjCImpls.find(D);
1212  if (I != ObjCImpls.end())
1213    return cast<ObjCImplementationDecl>(I->second);
1214  return 0;
1215}
1216/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
1217ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
1218  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1219    I = ObjCImpls.find(D);
1220  if (I != ObjCImpls.end())
1221    return cast<ObjCCategoryImplDecl>(I->second);
1222  return 0;
1223}
1224
1225/// \brief Set the implementation of ObjCInterfaceDecl.
1226void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1227                           ObjCImplementationDecl *ImplD) {
1228  assert(IFaceD && ImplD && "Passed null params");
1229  ObjCImpls[IFaceD] = ImplD;
1230}
1231/// \brief Set the implementation of ObjCCategoryDecl.
1232void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1233                           ObjCCategoryImplDecl *ImplD) {
1234  assert(CatD && ImplD && "Passed null params");
1235  ObjCImpls[CatD] = ImplD;
1236}
1237
1238/// \brief Get the copy initialization expression of VarDecl,or NULL if
1239/// none exists.
1240Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
1241  assert(VD && "Passed null params");
1242  assert(VD->hasAttr<BlocksAttr>() &&
1243         "getBlockVarCopyInits - not __block var");
1244  llvm::DenseMap<const VarDecl*, Expr*>::iterator
1245    I = BlockVarCopyInits.find(VD);
1246  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : 0;
1247}
1248
1249/// \brief Set the copy inialization expression of a block var decl.
1250void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
1251  assert(VD && Init && "Passed null params");
1252  assert(VD->hasAttr<BlocksAttr>() &&
1253         "setBlockVarCopyInits - not __block var");
1254  BlockVarCopyInits[VD] = Init;
1255}
1256
1257/// \brief Allocate an uninitialized TypeSourceInfo.
1258///
1259/// The caller should initialize the memory held by TypeSourceInfo using
1260/// the TypeLoc wrappers.
1261///
1262/// \param T the type that will be the basis for type source info. This type
1263/// should refer to how the declarator was written in source code, not to
1264/// what type semantic analysis resolved the declarator to.
1265TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1266                                                 unsigned DataSize) const {
1267  if (!DataSize)
1268    DataSize = TypeLoc::getFullDataSizeForType(T);
1269  else
1270    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1271           "incorrect data size provided to CreateTypeSourceInfo!");
1272
1273  TypeSourceInfo *TInfo =
1274    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1275  new (TInfo) TypeSourceInfo(T);
1276  return TInfo;
1277}
1278
1279TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1280                                                     SourceLocation L) const {
1281  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1282  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
1283  return DI;
1284}
1285
1286const ASTRecordLayout &
1287ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
1288  return getObjCLayout(D, 0);
1289}
1290
1291const ASTRecordLayout &
1292ASTContext::getASTObjCImplementationLayout(
1293                                        const ObjCImplementationDecl *D) const {
1294  return getObjCLayout(D->getClassInterface(), D);
1295}
1296
1297//===----------------------------------------------------------------------===//
1298//                   Type creation/memoization methods
1299//===----------------------------------------------------------------------===//
1300
1301QualType
1302ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
1303  unsigned fastQuals = quals.getFastQualifiers();
1304  quals.removeFastQualifiers();
1305
1306  // Check if we've already instantiated this type.
1307  llvm::FoldingSetNodeID ID;
1308  ExtQuals::Profile(ID, baseType, quals);
1309  void *insertPos = 0;
1310  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
1311    assert(eq->getQualifiers() == quals);
1312    return QualType(eq, fastQuals);
1313  }
1314
1315  // If the base type is not canonical, make the appropriate canonical type.
1316  QualType canon;
1317  if (!baseType->isCanonicalUnqualified()) {
1318    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
1319    canonSplit.second.addConsistentQualifiers(quals);
1320    canon = getExtQualType(canonSplit.first, canonSplit.second);
1321
1322    // Re-find the insert position.
1323    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
1324  }
1325
1326  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
1327  ExtQualNodes.InsertNode(eq, insertPos);
1328  return QualType(eq, fastQuals);
1329}
1330
1331QualType
1332ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
1333  QualType CanT = getCanonicalType(T);
1334  if (CanT.getAddressSpace() == AddressSpace)
1335    return T;
1336
1337  // If we are composing extended qualifiers together, merge together
1338  // into one ExtQuals node.
1339  QualifierCollector Quals;
1340  const Type *TypeNode = Quals.strip(T);
1341
1342  // If this type already has an address space specified, it cannot get
1343  // another one.
1344  assert(!Quals.hasAddressSpace() &&
1345         "Type cannot be in multiple addr spaces!");
1346  Quals.addAddressSpace(AddressSpace);
1347
1348  return getExtQualType(TypeNode, Quals);
1349}
1350
1351QualType ASTContext::getObjCGCQualType(QualType T,
1352                                       Qualifiers::GC GCAttr) const {
1353  QualType CanT = getCanonicalType(T);
1354  if (CanT.getObjCGCAttr() == GCAttr)
1355    return T;
1356
1357  if (const PointerType *ptr = T->getAs<PointerType>()) {
1358    QualType Pointee = ptr->getPointeeType();
1359    if (Pointee->isAnyPointerType()) {
1360      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1361      return getPointerType(ResultType);
1362    }
1363  }
1364
1365  // If we are composing extended qualifiers together, merge together
1366  // into one ExtQuals node.
1367  QualifierCollector Quals;
1368  const Type *TypeNode = Quals.strip(T);
1369
1370  // If this type already has an ObjCGC specified, it cannot get
1371  // another one.
1372  assert(!Quals.hasObjCGCAttr() &&
1373         "Type cannot have multiple ObjCGCs!");
1374  Quals.addObjCGCAttr(GCAttr);
1375
1376  return getExtQualType(TypeNode, Quals);
1377}
1378
1379const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
1380                                                   FunctionType::ExtInfo Info) {
1381  if (T->getExtInfo() == Info)
1382    return T;
1383
1384  QualType Result;
1385  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
1386    Result = getFunctionNoProtoType(FNPT->getResultType(), Info);
1387  } else {
1388    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
1389    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
1390    EPI.ExtInfo = Info;
1391    Result = getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1392                             FPT->getNumArgs(), EPI);
1393  }
1394
1395  return cast<FunctionType>(Result.getTypePtr());
1396}
1397
1398/// getComplexType - Return the uniqued reference to the type for a complex
1399/// number with the specified element type.
1400QualType ASTContext::getComplexType(QualType T) const {
1401  // Unique pointers, to guarantee there is only one pointer of a particular
1402  // structure.
1403  llvm::FoldingSetNodeID ID;
1404  ComplexType::Profile(ID, T);
1405
1406  void *InsertPos = 0;
1407  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1408    return QualType(CT, 0);
1409
1410  // If the pointee type isn't canonical, this won't be a canonical type either,
1411  // so fill in the canonical type field.
1412  QualType Canonical;
1413  if (!T.isCanonical()) {
1414    Canonical = getComplexType(getCanonicalType(T));
1415
1416    // Get the new insert position for the node we care about.
1417    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1418    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1419  }
1420  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1421  Types.push_back(New);
1422  ComplexTypes.InsertNode(New, InsertPos);
1423  return QualType(New, 0);
1424}
1425
1426/// getPointerType - Return the uniqued reference to the type for a pointer to
1427/// the specified type.
1428QualType ASTContext::getPointerType(QualType T) const {
1429  // Unique pointers, to guarantee there is only one pointer of a particular
1430  // structure.
1431  llvm::FoldingSetNodeID ID;
1432  PointerType::Profile(ID, T);
1433
1434  void *InsertPos = 0;
1435  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1436    return QualType(PT, 0);
1437
1438  // If the pointee type isn't canonical, this won't be a canonical type either,
1439  // so fill in the canonical type field.
1440  QualType Canonical;
1441  if (!T.isCanonical()) {
1442    Canonical = getPointerType(getCanonicalType(T));
1443
1444    // Get the new insert position for the node we care about.
1445    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1446    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1447  }
1448  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1449  Types.push_back(New);
1450  PointerTypes.InsertNode(New, InsertPos);
1451  return QualType(New, 0);
1452}
1453
1454/// getBlockPointerType - Return the uniqued reference to the type for
1455/// a pointer to the specified block.
1456QualType ASTContext::getBlockPointerType(QualType T) const {
1457  assert(T->isFunctionType() && "block of function types only");
1458  // Unique pointers, to guarantee there is only one block of a particular
1459  // structure.
1460  llvm::FoldingSetNodeID ID;
1461  BlockPointerType::Profile(ID, T);
1462
1463  void *InsertPos = 0;
1464  if (BlockPointerType *PT =
1465        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1466    return QualType(PT, 0);
1467
1468  // If the block pointee type isn't canonical, this won't be a canonical
1469  // type either so fill in the canonical type field.
1470  QualType Canonical;
1471  if (!T.isCanonical()) {
1472    Canonical = getBlockPointerType(getCanonicalType(T));
1473
1474    // Get the new insert position for the node we care about.
1475    BlockPointerType *NewIP =
1476      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1477    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1478  }
1479  BlockPointerType *New
1480    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1481  Types.push_back(New);
1482  BlockPointerTypes.InsertNode(New, InsertPos);
1483  return QualType(New, 0);
1484}
1485
1486/// getLValueReferenceType - Return the uniqued reference to the type for an
1487/// lvalue reference to the specified type.
1488QualType
1489ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
1490  assert(getCanonicalType(T) != OverloadTy &&
1491         "Unresolved overloaded function type");
1492
1493  // Unique pointers, to guarantee there is only one pointer of a particular
1494  // structure.
1495  llvm::FoldingSetNodeID ID;
1496  ReferenceType::Profile(ID, T, SpelledAsLValue);
1497
1498  void *InsertPos = 0;
1499  if (LValueReferenceType *RT =
1500        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1501    return QualType(RT, 0);
1502
1503  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1504
1505  // If the referencee type isn't canonical, this won't be a canonical type
1506  // either, so fill in the canonical type field.
1507  QualType Canonical;
1508  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1509    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1510    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1511
1512    // Get the new insert position for the node we care about.
1513    LValueReferenceType *NewIP =
1514      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1515    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1516  }
1517
1518  LValueReferenceType *New
1519    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1520                                                     SpelledAsLValue);
1521  Types.push_back(New);
1522  LValueReferenceTypes.InsertNode(New, InsertPos);
1523
1524  return QualType(New, 0);
1525}
1526
1527/// getRValueReferenceType - Return the uniqued reference to the type for an
1528/// rvalue reference to the specified type.
1529QualType ASTContext::getRValueReferenceType(QualType T) const {
1530  // Unique pointers, to guarantee there is only one pointer of a particular
1531  // structure.
1532  llvm::FoldingSetNodeID ID;
1533  ReferenceType::Profile(ID, T, false);
1534
1535  void *InsertPos = 0;
1536  if (RValueReferenceType *RT =
1537        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1538    return QualType(RT, 0);
1539
1540  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1541
1542  // If the referencee type isn't canonical, this won't be a canonical type
1543  // either, so fill in the canonical type field.
1544  QualType Canonical;
1545  if (InnerRef || !T.isCanonical()) {
1546    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1547    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1548
1549    // Get the new insert position for the node we care about.
1550    RValueReferenceType *NewIP =
1551      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1552    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1553  }
1554
1555  RValueReferenceType *New
1556    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1557  Types.push_back(New);
1558  RValueReferenceTypes.InsertNode(New, InsertPos);
1559  return QualType(New, 0);
1560}
1561
1562/// getMemberPointerType - Return the uniqued reference to the type for a
1563/// member pointer to the specified type, in the specified class.
1564QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
1565  // Unique pointers, to guarantee there is only one pointer of a particular
1566  // structure.
1567  llvm::FoldingSetNodeID ID;
1568  MemberPointerType::Profile(ID, T, Cls);
1569
1570  void *InsertPos = 0;
1571  if (MemberPointerType *PT =
1572      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1573    return QualType(PT, 0);
1574
1575  // If the pointee or class type isn't canonical, this won't be a canonical
1576  // type either, so fill in the canonical type field.
1577  QualType Canonical;
1578  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1579    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1580
1581    // Get the new insert position for the node we care about.
1582    MemberPointerType *NewIP =
1583      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1584    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1585  }
1586  MemberPointerType *New
1587    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1588  Types.push_back(New);
1589  MemberPointerTypes.InsertNode(New, InsertPos);
1590  return QualType(New, 0);
1591}
1592
1593/// getConstantArrayType - Return the unique reference to the type for an
1594/// array of the specified element type.
1595QualType ASTContext::getConstantArrayType(QualType EltTy,
1596                                          const llvm::APInt &ArySizeIn,
1597                                          ArrayType::ArraySizeModifier ASM,
1598                                          unsigned IndexTypeQuals) const {
1599  assert((EltTy->isDependentType() ||
1600          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1601         "Constant array of VLAs is illegal!");
1602
1603  // Convert the array size into a canonical width matching the pointer size for
1604  // the target.
1605  llvm::APInt ArySize(ArySizeIn);
1606  ArySize =
1607    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
1608
1609  llvm::FoldingSetNodeID ID;
1610  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
1611
1612  void *InsertPos = 0;
1613  if (ConstantArrayType *ATP =
1614      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1615    return QualType(ATP, 0);
1616
1617  // If the element type isn't canonical or has qualifiers, this won't
1618  // be a canonical type either, so fill in the canonical type field.
1619  QualType Canon;
1620  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1621    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1622    Canon = getConstantArrayType(QualType(canonSplit.first, 0), ArySize,
1623                                 ASM, IndexTypeQuals);
1624    Canon = getQualifiedType(Canon, canonSplit.second);
1625
1626    // Get the new insert position for the node we care about.
1627    ConstantArrayType *NewIP =
1628      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1629    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1630  }
1631
1632  ConstantArrayType *New = new(*this,TypeAlignment)
1633    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
1634  ConstantArrayTypes.InsertNode(New, InsertPos);
1635  Types.push_back(New);
1636  return QualType(New, 0);
1637}
1638
1639/// getVariableArrayDecayedType - Turns the given type, which may be
1640/// variably-modified, into the corresponding type with all the known
1641/// sizes replaced with [*].
1642QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
1643  // Vastly most common case.
1644  if (!type->isVariablyModifiedType()) return type;
1645
1646  QualType result;
1647
1648  SplitQualType split = type.getSplitDesugaredType();
1649  const Type *ty = split.first;
1650  switch (ty->getTypeClass()) {
1651#define TYPE(Class, Base)
1652#define ABSTRACT_TYPE(Class, Base)
1653#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
1654#include "clang/AST/TypeNodes.def"
1655    llvm_unreachable("didn't desugar past all non-canonical types?");
1656
1657  // These types should never be variably-modified.
1658  case Type::Builtin:
1659  case Type::Complex:
1660  case Type::Vector:
1661  case Type::ExtVector:
1662  case Type::DependentSizedExtVector:
1663  case Type::ObjCObject:
1664  case Type::ObjCInterface:
1665  case Type::ObjCObjectPointer:
1666  case Type::Record:
1667  case Type::Enum:
1668  case Type::UnresolvedUsing:
1669  case Type::TypeOfExpr:
1670  case Type::TypeOf:
1671  case Type::Decltype:
1672  case Type::UnaryTransform:
1673  case Type::DependentName:
1674  case Type::InjectedClassName:
1675  case Type::TemplateSpecialization:
1676  case Type::DependentTemplateSpecialization:
1677  case Type::TemplateTypeParm:
1678  case Type::SubstTemplateTypeParmPack:
1679  case Type::Auto:
1680  case Type::PackExpansion:
1681    llvm_unreachable("type should never be variably-modified");
1682
1683  // These types can be variably-modified but should never need to
1684  // further decay.
1685  case Type::FunctionNoProto:
1686  case Type::FunctionProto:
1687  case Type::BlockPointer:
1688  case Type::MemberPointer:
1689    return type;
1690
1691  // These types can be variably-modified.  All these modifications
1692  // preserve structure except as noted by comments.
1693  // TODO: if we ever care about optimizing VLAs, there are no-op
1694  // optimizations available here.
1695  case Type::Pointer:
1696    result = getPointerType(getVariableArrayDecayedType(
1697                              cast<PointerType>(ty)->getPointeeType()));
1698    break;
1699
1700  case Type::LValueReference: {
1701    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
1702    result = getLValueReferenceType(
1703                 getVariableArrayDecayedType(lv->getPointeeType()),
1704                                    lv->isSpelledAsLValue());
1705    break;
1706  }
1707
1708  case Type::RValueReference: {
1709    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
1710    result = getRValueReferenceType(
1711                 getVariableArrayDecayedType(lv->getPointeeType()));
1712    break;
1713  }
1714
1715  case Type::Atomic: {
1716    const AtomicType *at = cast<AtomicType>(ty);
1717    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
1718    break;
1719  }
1720
1721  case Type::ConstantArray: {
1722    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
1723    result = getConstantArrayType(
1724                 getVariableArrayDecayedType(cat->getElementType()),
1725                                  cat->getSize(),
1726                                  cat->getSizeModifier(),
1727                                  cat->getIndexTypeCVRQualifiers());
1728    break;
1729  }
1730
1731  case Type::DependentSizedArray: {
1732    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
1733    result = getDependentSizedArrayType(
1734                 getVariableArrayDecayedType(dat->getElementType()),
1735                                        dat->getSizeExpr(),
1736                                        dat->getSizeModifier(),
1737                                        dat->getIndexTypeCVRQualifiers(),
1738                                        dat->getBracketsRange());
1739    break;
1740  }
1741
1742  // Turn incomplete types into [*] types.
1743  case Type::IncompleteArray: {
1744    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
1745    result = getVariableArrayType(
1746                 getVariableArrayDecayedType(iat->getElementType()),
1747                                  /*size*/ 0,
1748                                  ArrayType::Normal,
1749                                  iat->getIndexTypeCVRQualifiers(),
1750                                  SourceRange());
1751    break;
1752  }
1753
1754  // Turn VLA types into [*] types.
1755  case Type::VariableArray: {
1756    const VariableArrayType *vat = cast<VariableArrayType>(ty);
1757    result = getVariableArrayType(
1758                 getVariableArrayDecayedType(vat->getElementType()),
1759                                  /*size*/ 0,
1760                                  ArrayType::Star,
1761                                  vat->getIndexTypeCVRQualifiers(),
1762                                  vat->getBracketsRange());
1763    break;
1764  }
1765  }
1766
1767  // Apply the top-level qualifiers from the original.
1768  return getQualifiedType(result, split.second);
1769}
1770
1771/// getVariableArrayType - Returns a non-unique reference to the type for a
1772/// variable array of the specified element type.
1773QualType ASTContext::getVariableArrayType(QualType EltTy,
1774                                          Expr *NumElts,
1775                                          ArrayType::ArraySizeModifier ASM,
1776                                          unsigned IndexTypeQuals,
1777                                          SourceRange Brackets) const {
1778  // Since we don't unique expressions, it isn't possible to unique VLA's
1779  // that have an expression provided for their size.
1780  QualType Canon;
1781
1782  // Be sure to pull qualifiers off the element type.
1783  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1784    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1785    Canon = getVariableArrayType(QualType(canonSplit.first, 0), NumElts, ASM,
1786                                 IndexTypeQuals, Brackets);
1787    Canon = getQualifiedType(Canon, canonSplit.second);
1788  }
1789
1790  VariableArrayType *New = new(*this, TypeAlignment)
1791    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
1792
1793  VariableArrayTypes.push_back(New);
1794  Types.push_back(New);
1795  return QualType(New, 0);
1796}
1797
1798/// getDependentSizedArrayType - Returns a non-unique reference to
1799/// the type for a dependently-sized array of the specified element
1800/// type.
1801QualType ASTContext::getDependentSizedArrayType(QualType elementType,
1802                                                Expr *numElements,
1803                                                ArrayType::ArraySizeModifier ASM,
1804                                                unsigned elementTypeQuals,
1805                                                SourceRange brackets) const {
1806  assert((!numElements || numElements->isTypeDependent() ||
1807          numElements->isValueDependent()) &&
1808         "Size must be type- or value-dependent!");
1809
1810  // Dependently-sized array types that do not have a specified number
1811  // of elements will have their sizes deduced from a dependent
1812  // initializer.  We do no canonicalization here at all, which is okay
1813  // because they can't be used in most locations.
1814  if (!numElements) {
1815    DependentSizedArrayType *newType
1816      = new (*this, TypeAlignment)
1817          DependentSizedArrayType(*this, elementType, QualType(),
1818                                  numElements, ASM, elementTypeQuals,
1819                                  brackets);
1820    Types.push_back(newType);
1821    return QualType(newType, 0);
1822  }
1823
1824  // Otherwise, we actually build a new type every time, but we
1825  // also build a canonical type.
1826
1827  SplitQualType canonElementType = getCanonicalType(elementType).split();
1828
1829  void *insertPos = 0;
1830  llvm::FoldingSetNodeID ID;
1831  DependentSizedArrayType::Profile(ID, *this,
1832                                   QualType(canonElementType.first, 0),
1833                                   ASM, elementTypeQuals, numElements);
1834
1835  // Look for an existing type with these properties.
1836  DependentSizedArrayType *canonTy =
1837    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1838
1839  // If we don't have one, build one.
1840  if (!canonTy) {
1841    canonTy = new (*this, TypeAlignment)
1842      DependentSizedArrayType(*this, QualType(canonElementType.first, 0),
1843                              QualType(), numElements, ASM, elementTypeQuals,
1844                              brackets);
1845    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
1846    Types.push_back(canonTy);
1847  }
1848
1849  // Apply qualifiers from the element type to the array.
1850  QualType canon = getQualifiedType(QualType(canonTy,0),
1851                                    canonElementType.second);
1852
1853  // If we didn't need extra canonicalization for the element type,
1854  // then just use that as our result.
1855  if (QualType(canonElementType.first, 0) == elementType)
1856    return canon;
1857
1858  // Otherwise, we need to build a type which follows the spelling
1859  // of the element type.
1860  DependentSizedArrayType *sugaredType
1861    = new (*this, TypeAlignment)
1862        DependentSizedArrayType(*this, elementType, canon, numElements,
1863                                ASM, elementTypeQuals, brackets);
1864  Types.push_back(sugaredType);
1865  return QualType(sugaredType, 0);
1866}
1867
1868QualType ASTContext::getIncompleteArrayType(QualType elementType,
1869                                            ArrayType::ArraySizeModifier ASM,
1870                                            unsigned elementTypeQuals) const {
1871  llvm::FoldingSetNodeID ID;
1872  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
1873
1874  void *insertPos = 0;
1875  if (IncompleteArrayType *iat =
1876       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
1877    return QualType(iat, 0);
1878
1879  // If the element type isn't canonical, this won't be a canonical type
1880  // either, so fill in the canonical type field.  We also have to pull
1881  // qualifiers off the element type.
1882  QualType canon;
1883
1884  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
1885    SplitQualType canonSplit = getCanonicalType(elementType).split();
1886    canon = getIncompleteArrayType(QualType(canonSplit.first, 0),
1887                                   ASM, elementTypeQuals);
1888    canon = getQualifiedType(canon, canonSplit.second);
1889
1890    // Get the new insert position for the node we care about.
1891    IncompleteArrayType *existing =
1892      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1893    assert(!existing && "Shouldn't be in the map!"); (void) existing;
1894  }
1895
1896  IncompleteArrayType *newType = new (*this, TypeAlignment)
1897    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
1898
1899  IncompleteArrayTypes.InsertNode(newType, insertPos);
1900  Types.push_back(newType);
1901  return QualType(newType, 0);
1902}
1903
1904/// getVectorType - Return the unique reference to a vector type of
1905/// the specified element type and size. VectorType must be a built-in type.
1906QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1907                                   VectorType::VectorKind VecKind) const {
1908  assert(vecType->isBuiltinType());
1909
1910  // Check if we've already instantiated a vector of this type.
1911  llvm::FoldingSetNodeID ID;
1912  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
1913
1914  void *InsertPos = 0;
1915  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1916    return QualType(VTP, 0);
1917
1918  // If the element type isn't canonical, this won't be a canonical type either,
1919  // so fill in the canonical type field.
1920  QualType Canonical;
1921  if (!vecType.isCanonical()) {
1922    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
1923
1924    // Get the new insert position for the node we care about.
1925    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1926    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1927  }
1928  VectorType *New = new (*this, TypeAlignment)
1929    VectorType(vecType, NumElts, Canonical, VecKind);
1930  VectorTypes.InsertNode(New, InsertPos);
1931  Types.push_back(New);
1932  return QualType(New, 0);
1933}
1934
1935/// getExtVectorType - Return the unique reference to an extended vector type of
1936/// the specified element type and size. VectorType must be a built-in type.
1937QualType
1938ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
1939  assert(vecType->isBuiltinType() || vecType->isDependentType());
1940
1941  // Check if we've already instantiated a vector of this type.
1942  llvm::FoldingSetNodeID ID;
1943  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1944                      VectorType::GenericVector);
1945  void *InsertPos = 0;
1946  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1947    return QualType(VTP, 0);
1948
1949  // If the element type isn't canonical, this won't be a canonical type either,
1950  // so fill in the canonical type field.
1951  QualType Canonical;
1952  if (!vecType.isCanonical()) {
1953    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
1954
1955    // Get the new insert position for the node we care about.
1956    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1957    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1958  }
1959  ExtVectorType *New = new (*this, TypeAlignment)
1960    ExtVectorType(vecType, NumElts, Canonical);
1961  VectorTypes.InsertNode(New, InsertPos);
1962  Types.push_back(New);
1963  return QualType(New, 0);
1964}
1965
1966QualType
1967ASTContext::getDependentSizedExtVectorType(QualType vecType,
1968                                           Expr *SizeExpr,
1969                                           SourceLocation AttrLoc) const {
1970  llvm::FoldingSetNodeID ID;
1971  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
1972                                       SizeExpr);
1973
1974  void *InsertPos = 0;
1975  DependentSizedExtVectorType *Canon
1976    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1977  DependentSizedExtVectorType *New;
1978  if (Canon) {
1979    // We already have a canonical version of this array type; use it as
1980    // the canonical type for a newly-built type.
1981    New = new (*this, TypeAlignment)
1982      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
1983                                  SizeExpr, AttrLoc);
1984  } else {
1985    QualType CanonVecTy = getCanonicalType(vecType);
1986    if (CanonVecTy == vecType) {
1987      New = new (*this, TypeAlignment)
1988        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
1989                                    AttrLoc);
1990
1991      DependentSizedExtVectorType *CanonCheck
1992        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1993      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
1994      (void)CanonCheck;
1995      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
1996    } else {
1997      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
1998                                                      SourceLocation());
1999      New = new (*this, TypeAlignment)
2000        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2001    }
2002  }
2003
2004  Types.push_back(New);
2005  return QualType(New, 0);
2006}
2007
2008/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
2009///
2010QualType
2011ASTContext::getFunctionNoProtoType(QualType ResultTy,
2012                                   const FunctionType::ExtInfo &Info) const {
2013  const CallingConv DefaultCC = Info.getCC();
2014  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2015                               CC_X86StdCall : DefaultCC;
2016  // Unique functions, to guarantee there is only one function of a particular
2017  // structure.
2018  llvm::FoldingSetNodeID ID;
2019  FunctionNoProtoType::Profile(ID, ResultTy, Info);
2020
2021  void *InsertPos = 0;
2022  if (FunctionNoProtoType *FT =
2023        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2024    return QualType(FT, 0);
2025
2026  QualType Canonical;
2027  if (!ResultTy.isCanonical() ||
2028      getCanonicalCallConv(CallConv) != CallConv) {
2029    Canonical =
2030      getFunctionNoProtoType(getCanonicalType(ResultTy),
2031                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
2032
2033    // Get the new insert position for the node we care about.
2034    FunctionNoProtoType *NewIP =
2035      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2036    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2037  }
2038
2039  FunctionProtoType::ExtInfo newInfo = Info.withCallingConv(CallConv);
2040  FunctionNoProtoType *New = new (*this, TypeAlignment)
2041    FunctionNoProtoType(ResultTy, Canonical, newInfo);
2042  Types.push_back(New);
2043  FunctionNoProtoTypes.InsertNode(New, InsertPos);
2044  return QualType(New, 0);
2045}
2046
2047/// getFunctionType - Return a normal function type with a typed argument
2048/// list.  isVariadic indicates whether the argument list includes '...'.
2049QualType
2050ASTContext::getFunctionType(QualType ResultTy,
2051                            const QualType *ArgArray, unsigned NumArgs,
2052                            const FunctionProtoType::ExtProtoInfo &EPI) const {
2053  // Unique functions, to guarantee there is only one function of a particular
2054  // structure.
2055  llvm::FoldingSetNodeID ID;
2056  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, EPI, *this);
2057
2058  void *InsertPos = 0;
2059  if (FunctionProtoType *FTP =
2060        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2061    return QualType(FTP, 0);
2062
2063  // Determine whether the type being created is already canonical or not.
2064  bool isCanonical= EPI.ExceptionSpecType == EST_None && ResultTy.isCanonical();
2065  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
2066    if (!ArgArray[i].isCanonicalAsParam())
2067      isCanonical = false;
2068
2069  const CallingConv DefaultCC = EPI.ExtInfo.getCC();
2070  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2071                               CC_X86StdCall : DefaultCC;
2072
2073  // If this type isn't canonical, get the canonical version of it.
2074  // The exception spec is not part of the canonical type.
2075  QualType Canonical;
2076  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
2077    SmallVector<QualType, 16> CanonicalArgs;
2078    CanonicalArgs.reserve(NumArgs);
2079    for (unsigned i = 0; i != NumArgs; ++i)
2080      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
2081
2082    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
2083    CanonicalEPI.ExceptionSpecType = EST_None;
2084    CanonicalEPI.NumExceptions = 0;
2085    CanonicalEPI.ExtInfo
2086      = CanonicalEPI.ExtInfo.withCallingConv(getCanonicalCallConv(CallConv));
2087
2088    Canonical = getFunctionType(getCanonicalType(ResultTy),
2089                                CanonicalArgs.data(), NumArgs,
2090                                CanonicalEPI);
2091
2092    // Get the new insert position for the node we care about.
2093    FunctionProtoType *NewIP =
2094      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2095    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2096  }
2097
2098  // FunctionProtoType objects are allocated with extra bytes after
2099  // them for three variable size arrays at the end:
2100  //  - parameter types
2101  //  - exception types
2102  //  - consumed-arguments flags
2103  // Instead of the exception types, there could be a noexcept
2104  // expression.
2105  size_t Size = sizeof(FunctionProtoType) +
2106                NumArgs * sizeof(QualType);
2107  if (EPI.ExceptionSpecType == EST_Dynamic)
2108    Size += EPI.NumExceptions * sizeof(QualType);
2109  else if (EPI.ExceptionSpecType == EST_ComputedNoexcept) {
2110    Size += sizeof(Expr*);
2111  }
2112  if (EPI.ConsumedArguments)
2113    Size += NumArgs * sizeof(bool);
2114
2115  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
2116  FunctionProtoType::ExtProtoInfo newEPI = EPI;
2117  newEPI.ExtInfo = EPI.ExtInfo.withCallingConv(CallConv);
2118  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, Canonical, newEPI);
2119  Types.push_back(FTP);
2120  FunctionProtoTypes.InsertNode(FTP, InsertPos);
2121  return QualType(FTP, 0);
2122}
2123
2124#ifndef NDEBUG
2125static bool NeedsInjectedClassNameType(const RecordDecl *D) {
2126  if (!isa<CXXRecordDecl>(D)) return false;
2127  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
2128  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
2129    return true;
2130  if (RD->getDescribedClassTemplate() &&
2131      !isa<ClassTemplateSpecializationDecl>(RD))
2132    return true;
2133  return false;
2134}
2135#endif
2136
2137/// getInjectedClassNameType - Return the unique reference to the
2138/// injected class name type for the specified templated declaration.
2139QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
2140                                              QualType TST) const {
2141  assert(NeedsInjectedClassNameType(Decl));
2142  if (Decl->TypeForDecl) {
2143    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2144  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDeclaration()) {
2145    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
2146    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2147    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2148  } else {
2149    Type *newType =
2150      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
2151    Decl->TypeForDecl = newType;
2152    Types.push_back(newType);
2153  }
2154  return QualType(Decl->TypeForDecl, 0);
2155}
2156
2157/// getTypeDeclType - Return the unique reference to the type for the
2158/// specified type declaration.
2159QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) const {
2160  assert(Decl && "Passed null for Decl param");
2161  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
2162
2163  if (const TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Decl))
2164    return getTypedefType(Typedef);
2165
2166  assert(!isa<TemplateTypeParmDecl>(Decl) &&
2167         "Template type parameter types are always available.");
2168
2169  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
2170    assert(!Record->getPreviousDeclaration() &&
2171           "struct/union has previous declaration");
2172    assert(!NeedsInjectedClassNameType(Record));
2173    return getRecordType(Record);
2174  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
2175    assert(!Enum->getPreviousDeclaration() &&
2176           "enum has previous declaration");
2177    return getEnumType(Enum);
2178  } else if (const UnresolvedUsingTypenameDecl *Using =
2179               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
2180    Type *newType = new (*this, TypeAlignment) UnresolvedUsingType(Using);
2181    Decl->TypeForDecl = newType;
2182    Types.push_back(newType);
2183  } else
2184    llvm_unreachable("TypeDecl without a type?");
2185
2186  return QualType(Decl->TypeForDecl, 0);
2187}
2188
2189/// getTypedefType - Return the unique reference to the type for the
2190/// specified typedef name decl.
2191QualType
2192ASTContext::getTypedefType(const TypedefNameDecl *Decl,
2193                           QualType Canonical) const {
2194  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2195
2196  if (Canonical.isNull())
2197    Canonical = getCanonicalType(Decl->getUnderlyingType());
2198  TypedefType *newType = new(*this, TypeAlignment)
2199    TypedefType(Type::Typedef, Decl, Canonical);
2200  Decl->TypeForDecl = newType;
2201  Types.push_back(newType);
2202  return QualType(newType, 0);
2203}
2204
2205QualType ASTContext::getRecordType(const RecordDecl *Decl) const {
2206  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2207
2208  if (const RecordDecl *PrevDecl = Decl->getPreviousDeclaration())
2209    if (PrevDecl->TypeForDecl)
2210      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2211
2212  RecordType *newType = new (*this, TypeAlignment) RecordType(Decl);
2213  Decl->TypeForDecl = newType;
2214  Types.push_back(newType);
2215  return QualType(newType, 0);
2216}
2217
2218QualType ASTContext::getEnumType(const EnumDecl *Decl) const {
2219  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2220
2221  if (const EnumDecl *PrevDecl = Decl->getPreviousDeclaration())
2222    if (PrevDecl->TypeForDecl)
2223      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2224
2225  EnumType *newType = new (*this, TypeAlignment) EnumType(Decl);
2226  Decl->TypeForDecl = newType;
2227  Types.push_back(newType);
2228  return QualType(newType, 0);
2229}
2230
2231QualType ASTContext::getAttributedType(AttributedType::Kind attrKind,
2232                                       QualType modifiedType,
2233                                       QualType equivalentType) {
2234  llvm::FoldingSetNodeID id;
2235  AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
2236
2237  void *insertPos = 0;
2238  AttributedType *type = AttributedTypes.FindNodeOrInsertPos(id, insertPos);
2239  if (type) return QualType(type, 0);
2240
2241  QualType canon = getCanonicalType(equivalentType);
2242  type = new (*this, TypeAlignment)
2243           AttributedType(canon, attrKind, modifiedType, equivalentType);
2244
2245  Types.push_back(type);
2246  AttributedTypes.InsertNode(type, insertPos);
2247
2248  return QualType(type, 0);
2249}
2250
2251
2252/// \brief Retrieve a substitution-result type.
2253QualType
2254ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
2255                                         QualType Replacement) const {
2256  assert(Replacement.isCanonical()
2257         && "replacement types must always be canonical");
2258
2259  llvm::FoldingSetNodeID ID;
2260  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
2261  void *InsertPos = 0;
2262  SubstTemplateTypeParmType *SubstParm
2263    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2264
2265  if (!SubstParm) {
2266    SubstParm = new (*this, TypeAlignment)
2267      SubstTemplateTypeParmType(Parm, Replacement);
2268    Types.push_back(SubstParm);
2269    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2270  }
2271
2272  return QualType(SubstParm, 0);
2273}
2274
2275/// \brief Retrieve a
2276QualType ASTContext::getSubstTemplateTypeParmPackType(
2277                                          const TemplateTypeParmType *Parm,
2278                                              const TemplateArgument &ArgPack) {
2279#ifndef NDEBUG
2280  for (TemplateArgument::pack_iterator P = ArgPack.pack_begin(),
2281                                    PEnd = ArgPack.pack_end();
2282       P != PEnd; ++P) {
2283    assert(P->getKind() == TemplateArgument::Type &&"Pack contains a non-type");
2284    assert(P->getAsType().isCanonical() && "Pack contains non-canonical type");
2285  }
2286#endif
2287
2288  llvm::FoldingSetNodeID ID;
2289  SubstTemplateTypeParmPackType::Profile(ID, Parm, ArgPack);
2290  void *InsertPos = 0;
2291  if (SubstTemplateTypeParmPackType *SubstParm
2292        = SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos))
2293    return QualType(SubstParm, 0);
2294
2295  QualType Canon;
2296  if (!Parm->isCanonicalUnqualified()) {
2297    Canon = getCanonicalType(QualType(Parm, 0));
2298    Canon = getSubstTemplateTypeParmPackType(cast<TemplateTypeParmType>(Canon),
2299                                             ArgPack);
2300    SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos);
2301  }
2302
2303  SubstTemplateTypeParmPackType *SubstParm
2304    = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
2305                                                               ArgPack);
2306  Types.push_back(SubstParm);
2307  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2308  return QualType(SubstParm, 0);
2309}
2310
2311/// \brief Retrieve the template type parameter type for a template
2312/// parameter or parameter pack with the given depth, index, and (optionally)
2313/// name.
2314QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
2315                                             bool ParameterPack,
2316                                             TemplateTypeParmDecl *TTPDecl) const {
2317  llvm::FoldingSetNodeID ID;
2318  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, TTPDecl);
2319  void *InsertPos = 0;
2320  TemplateTypeParmType *TypeParm
2321    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2322
2323  if (TypeParm)
2324    return QualType(TypeParm, 0);
2325
2326  if (TTPDecl) {
2327    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
2328    TypeParm = new (*this, TypeAlignment) TemplateTypeParmType(TTPDecl, Canon);
2329
2330    TemplateTypeParmType *TypeCheck
2331      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2332    assert(!TypeCheck && "Template type parameter canonical type broken");
2333    (void)TypeCheck;
2334  } else
2335    TypeParm = new (*this, TypeAlignment)
2336      TemplateTypeParmType(Depth, Index, ParameterPack);
2337
2338  Types.push_back(TypeParm);
2339  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
2340
2341  return QualType(TypeParm, 0);
2342}
2343
2344TypeSourceInfo *
2345ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
2346                                              SourceLocation NameLoc,
2347                                        const TemplateArgumentListInfo &Args,
2348                                              QualType Underlying) const {
2349  assert(!Name.getAsDependentTemplateName() &&
2350         "No dependent template names here!");
2351  QualType TST = getTemplateSpecializationType(Name, Args, Underlying);
2352
2353  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
2354  TemplateSpecializationTypeLoc TL
2355    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
2356  TL.setTemplateNameLoc(NameLoc);
2357  TL.setLAngleLoc(Args.getLAngleLoc());
2358  TL.setRAngleLoc(Args.getRAngleLoc());
2359  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
2360    TL.setArgLocInfo(i, Args[i].getLocInfo());
2361  return DI;
2362}
2363
2364QualType
2365ASTContext::getTemplateSpecializationType(TemplateName Template,
2366                                          const TemplateArgumentListInfo &Args,
2367                                          QualType Underlying) const {
2368  assert(!Template.getAsDependentTemplateName() &&
2369         "No dependent template names here!");
2370
2371  unsigned NumArgs = Args.size();
2372
2373  SmallVector<TemplateArgument, 4> ArgVec;
2374  ArgVec.reserve(NumArgs);
2375  for (unsigned i = 0; i != NumArgs; ++i)
2376    ArgVec.push_back(Args[i].getArgument());
2377
2378  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
2379                                       Underlying);
2380}
2381
2382QualType
2383ASTContext::getTemplateSpecializationType(TemplateName Template,
2384                                          const TemplateArgument *Args,
2385                                          unsigned NumArgs,
2386                                          QualType Underlying) const {
2387  assert(!Template.getAsDependentTemplateName() &&
2388         "No dependent template names here!");
2389  // Look through qualified template names.
2390  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2391    Template = TemplateName(QTN->getTemplateDecl());
2392
2393  bool isTypeAlias =
2394    Template.getAsTemplateDecl() &&
2395    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
2396
2397  QualType CanonType;
2398  if (!Underlying.isNull())
2399    CanonType = getCanonicalType(Underlying);
2400  else {
2401    assert(!isTypeAlias &&
2402           "Underlying type for template alias must be computed by caller");
2403    CanonType = getCanonicalTemplateSpecializationType(Template, Args,
2404                                                       NumArgs);
2405  }
2406
2407  // Allocate the (non-canonical) template specialization type, but don't
2408  // try to unique it: these types typically have location information that
2409  // we don't unique and don't want to lose.
2410  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
2411                       sizeof(TemplateArgument) * NumArgs +
2412                       (isTypeAlias ? sizeof(QualType) : 0),
2413                       TypeAlignment);
2414  TemplateSpecializationType *Spec
2415    = new (Mem) TemplateSpecializationType(Template,
2416                                           Args, NumArgs,
2417                                           CanonType,
2418                                         isTypeAlias ? Underlying : QualType());
2419
2420  Types.push_back(Spec);
2421  return QualType(Spec, 0);
2422}
2423
2424QualType
2425ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
2426                                                   const TemplateArgument *Args,
2427                                                   unsigned NumArgs) const {
2428  assert(!Template.getAsDependentTemplateName() &&
2429         "No dependent template names here!");
2430  assert((!Template.getAsTemplateDecl() ||
2431          !isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl())) &&
2432         "Underlying type for template alias must be computed by caller");
2433
2434  // Look through qualified template names.
2435  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2436    Template = TemplateName(QTN->getTemplateDecl());
2437
2438  // Build the canonical template specialization type.
2439  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
2440  SmallVector<TemplateArgument, 4> CanonArgs;
2441  CanonArgs.reserve(NumArgs);
2442  for (unsigned I = 0; I != NumArgs; ++I)
2443    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
2444
2445  // Determine whether this canonical template specialization type already
2446  // exists.
2447  llvm::FoldingSetNodeID ID;
2448  TemplateSpecializationType::Profile(ID, CanonTemplate,
2449                                      CanonArgs.data(), NumArgs, *this);
2450
2451  void *InsertPos = 0;
2452  TemplateSpecializationType *Spec
2453    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2454
2455  if (!Spec) {
2456    // Allocate a new canonical template specialization type.
2457    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2458                          sizeof(TemplateArgument) * NumArgs),
2459                         TypeAlignment);
2460    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
2461                                                CanonArgs.data(), NumArgs,
2462                                                QualType(), QualType());
2463    Types.push_back(Spec);
2464    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
2465  }
2466
2467  assert(Spec->isDependentType() &&
2468         "Non-dependent template-id type must have a canonical type");
2469  return QualType(Spec, 0);
2470}
2471
2472QualType
2473ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
2474                              NestedNameSpecifier *NNS,
2475                              QualType NamedType) const {
2476  llvm::FoldingSetNodeID ID;
2477  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2478
2479  void *InsertPos = 0;
2480  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2481  if (T)
2482    return QualType(T, 0);
2483
2484  QualType Canon = NamedType;
2485  if (!Canon.isCanonical()) {
2486    Canon = getCanonicalType(NamedType);
2487    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2488    assert(!CheckT && "Elaborated canonical type broken");
2489    (void)CheckT;
2490  }
2491
2492  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2493  Types.push_back(T);
2494  ElaboratedTypes.InsertNode(T, InsertPos);
2495  return QualType(T, 0);
2496}
2497
2498QualType
2499ASTContext::getParenType(QualType InnerType) const {
2500  llvm::FoldingSetNodeID ID;
2501  ParenType::Profile(ID, InnerType);
2502
2503  void *InsertPos = 0;
2504  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2505  if (T)
2506    return QualType(T, 0);
2507
2508  QualType Canon = InnerType;
2509  if (!Canon.isCanonical()) {
2510    Canon = getCanonicalType(InnerType);
2511    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2512    assert(!CheckT && "Paren canonical type broken");
2513    (void)CheckT;
2514  }
2515
2516  T = new (*this) ParenType(InnerType, Canon);
2517  Types.push_back(T);
2518  ParenTypes.InsertNode(T, InsertPos);
2519  return QualType(T, 0);
2520}
2521
2522QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2523                                          NestedNameSpecifier *NNS,
2524                                          const IdentifierInfo *Name,
2525                                          QualType Canon) const {
2526  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2527
2528  if (Canon.isNull()) {
2529    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2530    ElaboratedTypeKeyword CanonKeyword = Keyword;
2531    if (Keyword == ETK_None)
2532      CanonKeyword = ETK_Typename;
2533
2534    if (CanonNNS != NNS || CanonKeyword != Keyword)
2535      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2536  }
2537
2538  llvm::FoldingSetNodeID ID;
2539  DependentNameType::Profile(ID, Keyword, NNS, Name);
2540
2541  void *InsertPos = 0;
2542  DependentNameType *T
2543    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2544  if (T)
2545    return QualType(T, 0);
2546
2547  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2548  Types.push_back(T);
2549  DependentNameTypes.InsertNode(T, InsertPos);
2550  return QualType(T, 0);
2551}
2552
2553QualType
2554ASTContext::getDependentTemplateSpecializationType(
2555                                 ElaboratedTypeKeyword Keyword,
2556                                 NestedNameSpecifier *NNS,
2557                                 const IdentifierInfo *Name,
2558                                 const TemplateArgumentListInfo &Args) const {
2559  // TODO: avoid this copy
2560  SmallVector<TemplateArgument, 16> ArgCopy;
2561  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2562    ArgCopy.push_back(Args[I].getArgument());
2563  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2564                                                ArgCopy.size(),
2565                                                ArgCopy.data());
2566}
2567
2568QualType
2569ASTContext::getDependentTemplateSpecializationType(
2570                                 ElaboratedTypeKeyword Keyword,
2571                                 NestedNameSpecifier *NNS,
2572                                 const IdentifierInfo *Name,
2573                                 unsigned NumArgs,
2574                                 const TemplateArgument *Args) const {
2575  assert((!NNS || NNS->isDependent()) &&
2576         "nested-name-specifier must be dependent");
2577
2578  llvm::FoldingSetNodeID ID;
2579  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2580                                               Name, NumArgs, Args);
2581
2582  void *InsertPos = 0;
2583  DependentTemplateSpecializationType *T
2584    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2585  if (T)
2586    return QualType(T, 0);
2587
2588  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2589
2590  ElaboratedTypeKeyword CanonKeyword = Keyword;
2591  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2592
2593  bool AnyNonCanonArgs = false;
2594  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2595  for (unsigned I = 0; I != NumArgs; ++I) {
2596    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2597    if (!CanonArgs[I].structurallyEquals(Args[I]))
2598      AnyNonCanonArgs = true;
2599  }
2600
2601  QualType Canon;
2602  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2603    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2604                                                   Name, NumArgs,
2605                                                   CanonArgs.data());
2606
2607    // Find the insert position again.
2608    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2609  }
2610
2611  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2612                        sizeof(TemplateArgument) * NumArgs),
2613                       TypeAlignment);
2614  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2615                                                    Name, NumArgs, Args, Canon);
2616  Types.push_back(T);
2617  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2618  return QualType(T, 0);
2619}
2620
2621QualType ASTContext::getPackExpansionType(QualType Pattern,
2622                                      llvm::Optional<unsigned> NumExpansions) {
2623  llvm::FoldingSetNodeID ID;
2624  PackExpansionType::Profile(ID, Pattern, NumExpansions);
2625
2626  assert(Pattern->containsUnexpandedParameterPack() &&
2627         "Pack expansions must expand one or more parameter packs");
2628  void *InsertPos = 0;
2629  PackExpansionType *T
2630    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2631  if (T)
2632    return QualType(T, 0);
2633
2634  QualType Canon;
2635  if (!Pattern.isCanonical()) {
2636    Canon = getPackExpansionType(getCanonicalType(Pattern), NumExpansions);
2637
2638    // Find the insert position again.
2639    PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2640  }
2641
2642  T = new (*this) PackExpansionType(Pattern, Canon, NumExpansions);
2643  Types.push_back(T);
2644  PackExpansionTypes.InsertNode(T, InsertPos);
2645  return QualType(T, 0);
2646}
2647
2648/// CmpProtocolNames - Comparison predicate for sorting protocols
2649/// alphabetically.
2650static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2651                            const ObjCProtocolDecl *RHS) {
2652  return LHS->getDeclName() < RHS->getDeclName();
2653}
2654
2655static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2656                                unsigned NumProtocols) {
2657  if (NumProtocols == 0) return true;
2658
2659  for (unsigned i = 1; i != NumProtocols; ++i)
2660    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]))
2661      return false;
2662  return true;
2663}
2664
2665static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2666                                   unsigned &NumProtocols) {
2667  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2668
2669  // Sort protocols, keyed by name.
2670  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2671
2672  // Remove duplicates.
2673  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2674  NumProtocols = ProtocolsEnd-Protocols;
2675}
2676
2677QualType ASTContext::getObjCObjectType(QualType BaseType,
2678                                       ObjCProtocolDecl * const *Protocols,
2679                                       unsigned NumProtocols) const {
2680  // If the base type is an interface and there aren't any protocols
2681  // to add, then the interface type will do just fine.
2682  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2683    return BaseType;
2684
2685  // Look in the folding set for an existing type.
2686  llvm::FoldingSetNodeID ID;
2687  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2688  void *InsertPos = 0;
2689  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2690    return QualType(QT, 0);
2691
2692  // Build the canonical type, which has the canonical base type and
2693  // a sorted-and-uniqued list of protocols.
2694  QualType Canonical;
2695  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2696  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2697    if (!ProtocolsSorted) {
2698      SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2699                                                     Protocols + NumProtocols);
2700      unsigned UniqueCount = NumProtocols;
2701
2702      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2703      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2704                                    &Sorted[0], UniqueCount);
2705    } else {
2706      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2707                                    Protocols, NumProtocols);
2708    }
2709
2710    // Regenerate InsertPos.
2711    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2712  }
2713
2714  unsigned Size = sizeof(ObjCObjectTypeImpl);
2715  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2716  void *Mem = Allocate(Size, TypeAlignment);
2717  ObjCObjectTypeImpl *T =
2718    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2719
2720  Types.push_back(T);
2721  ObjCObjectTypes.InsertNode(T, InsertPos);
2722  return QualType(T, 0);
2723}
2724
2725/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2726/// the given object type.
2727QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
2728  llvm::FoldingSetNodeID ID;
2729  ObjCObjectPointerType::Profile(ID, ObjectT);
2730
2731  void *InsertPos = 0;
2732  if (ObjCObjectPointerType *QT =
2733              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2734    return QualType(QT, 0);
2735
2736  // Find the canonical object type.
2737  QualType Canonical;
2738  if (!ObjectT.isCanonical()) {
2739    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2740
2741    // Regenerate InsertPos.
2742    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2743  }
2744
2745  // No match.
2746  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2747  ObjCObjectPointerType *QType =
2748    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2749
2750  Types.push_back(QType);
2751  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2752  return QualType(QType, 0);
2753}
2754
2755/// getObjCInterfaceType - Return the unique reference to the type for the
2756/// specified ObjC interface decl. The list of protocols is optional.
2757QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl) const {
2758  if (Decl->TypeForDecl)
2759    return QualType(Decl->TypeForDecl, 0);
2760
2761  // FIXME: redeclarations?
2762  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2763  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2764  Decl->TypeForDecl = T;
2765  Types.push_back(T);
2766  return QualType(T, 0);
2767}
2768
2769/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2770/// TypeOfExprType AST's (since expression's are never shared). For example,
2771/// multiple declarations that refer to "typeof(x)" all contain different
2772/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2773/// on canonical type's (which are always unique).
2774QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
2775  TypeOfExprType *toe;
2776  if (tofExpr->isTypeDependent()) {
2777    llvm::FoldingSetNodeID ID;
2778    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2779
2780    void *InsertPos = 0;
2781    DependentTypeOfExprType *Canon
2782      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2783    if (Canon) {
2784      // We already have a "canonical" version of an identical, dependent
2785      // typeof(expr) type. Use that as our canonical type.
2786      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2787                                          QualType((TypeOfExprType*)Canon, 0));
2788    } else {
2789      // Build a new, canonical typeof(expr) type.
2790      Canon
2791        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2792      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2793      toe = Canon;
2794    }
2795  } else {
2796    QualType Canonical = getCanonicalType(tofExpr->getType());
2797    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2798  }
2799  Types.push_back(toe);
2800  return QualType(toe, 0);
2801}
2802
2803/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2804/// TypeOfType AST's. The only motivation to unique these nodes would be
2805/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2806/// an issue. This doesn't effect the type checker, since it operates
2807/// on canonical type's (which are always unique).
2808QualType ASTContext::getTypeOfType(QualType tofType) const {
2809  QualType Canonical = getCanonicalType(tofType);
2810  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2811  Types.push_back(tot);
2812  return QualType(tot, 0);
2813}
2814
2815/// getDecltypeForExpr - Given an expr, will return the decltype for that
2816/// expression, according to the rules in C++0x [dcl.type.simple]p4
2817static QualType getDecltypeForExpr(const Expr *e, const ASTContext &Context) {
2818  if (e->isTypeDependent())
2819    return Context.DependentTy;
2820
2821  // If e is an id expression or a class member access, decltype(e) is defined
2822  // as the type of the entity named by e.
2823  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2824    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2825      return VD->getType();
2826  }
2827  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2828    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2829      return FD->getType();
2830  }
2831  // If e is a function call or an invocation of an overloaded operator,
2832  // (parentheses around e are ignored), decltype(e) is defined as the
2833  // return type of that function.
2834  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2835    return CE->getCallReturnType();
2836
2837  QualType T = e->getType();
2838
2839  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2840  // defined as T&, otherwise decltype(e) is defined as T.
2841  if (e->isLValue())
2842    T = Context.getLValueReferenceType(T);
2843
2844  return T;
2845}
2846
2847/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2848/// DecltypeType AST's. The only motivation to unique these nodes would be
2849/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2850/// an issue. This doesn't effect the type checker, since it operates
2851/// on canonical type's (which are always unique).
2852QualType ASTContext::getDecltypeType(Expr *e) const {
2853  DecltypeType *dt;
2854
2855  // C++0x [temp.type]p2:
2856  //   If an expression e involves a template parameter, decltype(e) denotes a
2857  //   unique dependent type. Two such decltype-specifiers refer to the same
2858  //   type only if their expressions are equivalent (14.5.6.1).
2859  if (e->isInstantiationDependent()) {
2860    llvm::FoldingSetNodeID ID;
2861    DependentDecltypeType::Profile(ID, *this, e);
2862
2863    void *InsertPos = 0;
2864    DependentDecltypeType *Canon
2865      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2866    if (Canon) {
2867      // We already have a "canonical" version of an equivalent, dependent
2868      // decltype type. Use that as our canonical type.
2869      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2870                                       QualType((DecltypeType*)Canon, 0));
2871    } else {
2872      // Build a new, canonical typeof(expr) type.
2873      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2874      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2875      dt = Canon;
2876    }
2877  } else {
2878    QualType T = getDecltypeForExpr(e, *this);
2879    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2880  }
2881  Types.push_back(dt);
2882  return QualType(dt, 0);
2883}
2884
2885/// getUnaryTransformationType - We don't unique these, since the memory
2886/// savings are minimal and these are rare.
2887QualType ASTContext::getUnaryTransformType(QualType BaseType,
2888                                           QualType UnderlyingType,
2889                                           UnaryTransformType::UTTKind Kind)
2890    const {
2891  UnaryTransformType *Ty =
2892    new (*this, TypeAlignment) UnaryTransformType (BaseType, UnderlyingType,
2893                                                   Kind,
2894                                 UnderlyingType->isDependentType() ?
2895                                    QualType() : UnderlyingType);
2896  Types.push_back(Ty);
2897  return QualType(Ty, 0);
2898}
2899
2900/// getAutoType - We only unique auto types after they've been deduced.
2901QualType ASTContext::getAutoType(QualType DeducedType) const {
2902  void *InsertPos = 0;
2903  if (!DeducedType.isNull()) {
2904    // Look in the folding set for an existing type.
2905    llvm::FoldingSetNodeID ID;
2906    AutoType::Profile(ID, DeducedType);
2907    if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
2908      return QualType(AT, 0);
2909  }
2910
2911  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType);
2912  Types.push_back(AT);
2913  if (InsertPos)
2914    AutoTypes.InsertNode(AT, InsertPos);
2915  return QualType(AT, 0);
2916}
2917
2918/// getAtomicType - Return the uniqued reference to the atomic type for
2919/// the given value type.
2920QualType ASTContext::getAtomicType(QualType T) const {
2921  // Unique pointers, to guarantee there is only one pointer of a particular
2922  // structure.
2923  llvm::FoldingSetNodeID ID;
2924  AtomicType::Profile(ID, T);
2925
2926  void *InsertPos = 0;
2927  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
2928    return QualType(AT, 0);
2929
2930  // If the atomic value type isn't canonical, this won't be a canonical type
2931  // either, so fill in the canonical type field.
2932  QualType Canonical;
2933  if (!T.isCanonical()) {
2934    Canonical = getAtomicType(getCanonicalType(T));
2935
2936    // Get the new insert position for the node we care about.
2937    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
2938    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2939  }
2940  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
2941  Types.push_back(New);
2942  AtomicTypes.InsertNode(New, InsertPos);
2943  return QualType(New, 0);
2944}
2945
2946/// getAutoDeductType - Get type pattern for deducing against 'auto'.
2947QualType ASTContext::getAutoDeductType() const {
2948  if (AutoDeductTy.isNull())
2949    AutoDeductTy = getAutoType(QualType());
2950  assert(!AutoDeductTy.isNull() && "can't build 'auto' pattern");
2951  return AutoDeductTy;
2952}
2953
2954/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
2955QualType ASTContext::getAutoRRefDeductType() const {
2956  if (AutoRRefDeductTy.isNull())
2957    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
2958  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
2959  return AutoRRefDeductTy;
2960}
2961
2962/// getTagDeclType - Return the unique reference to the type for the
2963/// specified TagDecl (struct/union/class/enum) decl.
2964QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
2965  assert (Decl);
2966  // FIXME: What is the design on getTagDeclType when it requires casting
2967  // away const?  mutable?
2968  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2969}
2970
2971/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2972/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2973/// needs to agree with the definition in <stddef.h>.
2974CanQualType ASTContext::getSizeType() const {
2975  return getFromTargetType(Target->getSizeType());
2976}
2977
2978/// getSignedWCharType - Return the type of "signed wchar_t".
2979/// Used when in C++, as a GCC extension.
2980QualType ASTContext::getSignedWCharType() const {
2981  // FIXME: derive from "Target" ?
2982  return WCharTy;
2983}
2984
2985/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
2986/// Used when in C++, as a GCC extension.
2987QualType ASTContext::getUnsignedWCharType() const {
2988  // FIXME: derive from "Target" ?
2989  return UnsignedIntTy;
2990}
2991
2992/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
2993/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
2994QualType ASTContext::getPointerDiffType() const {
2995  return getFromTargetType(Target->getPtrDiffType(0));
2996}
2997
2998//===----------------------------------------------------------------------===//
2999//                              Type Operators
3000//===----------------------------------------------------------------------===//
3001
3002CanQualType ASTContext::getCanonicalParamType(QualType T) const {
3003  // Push qualifiers into arrays, and then discard any remaining
3004  // qualifiers.
3005  T = getCanonicalType(T);
3006  T = getVariableArrayDecayedType(T);
3007  const Type *Ty = T.getTypePtr();
3008  QualType Result;
3009  if (isa<ArrayType>(Ty)) {
3010    Result = getArrayDecayedType(QualType(Ty,0));
3011  } else if (isa<FunctionType>(Ty)) {
3012    Result = getPointerType(QualType(Ty, 0));
3013  } else {
3014    Result = QualType(Ty, 0);
3015  }
3016
3017  return CanQualType::CreateUnsafe(Result);
3018}
3019
3020QualType ASTContext::getUnqualifiedArrayType(QualType type,
3021                                             Qualifiers &quals) {
3022  SplitQualType splitType = type.getSplitUnqualifiedType();
3023
3024  // FIXME: getSplitUnqualifiedType() actually walks all the way to
3025  // the unqualified desugared type and then drops it on the floor.
3026  // We then have to strip that sugar back off with
3027  // getUnqualifiedDesugaredType(), which is silly.
3028  const ArrayType *AT =
3029    dyn_cast<ArrayType>(splitType.first->getUnqualifiedDesugaredType());
3030
3031  // If we don't have an array, just use the results in splitType.
3032  if (!AT) {
3033    quals = splitType.second;
3034    return QualType(splitType.first, 0);
3035  }
3036
3037  // Otherwise, recurse on the array's element type.
3038  QualType elementType = AT->getElementType();
3039  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
3040
3041  // If that didn't change the element type, AT has no qualifiers, so we
3042  // can just use the results in splitType.
3043  if (elementType == unqualElementType) {
3044    assert(quals.empty()); // from the recursive call
3045    quals = splitType.second;
3046    return QualType(splitType.first, 0);
3047  }
3048
3049  // Otherwise, add in the qualifiers from the outermost type, then
3050  // build the type back up.
3051  quals.addConsistentQualifiers(splitType.second);
3052
3053  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
3054    return getConstantArrayType(unqualElementType, CAT->getSize(),
3055                                CAT->getSizeModifier(), 0);
3056  }
3057
3058  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
3059    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
3060  }
3061
3062  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
3063    return getVariableArrayType(unqualElementType,
3064                                VAT->getSizeExpr(),
3065                                VAT->getSizeModifier(),
3066                                VAT->getIndexTypeCVRQualifiers(),
3067                                VAT->getBracketsRange());
3068  }
3069
3070  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
3071  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
3072                                    DSAT->getSizeModifier(), 0,
3073                                    SourceRange());
3074}
3075
3076/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
3077/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
3078/// they point to and return true. If T1 and T2 aren't pointer types
3079/// or pointer-to-member types, or if they are not similar at this
3080/// level, returns false and leaves T1 and T2 unchanged. Top-level
3081/// qualifiers on T1 and T2 are ignored. This function will typically
3082/// be called in a loop that successively "unwraps" pointer and
3083/// pointer-to-member types to compare them at each level.
3084bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
3085  const PointerType *T1PtrType = T1->getAs<PointerType>(),
3086                    *T2PtrType = T2->getAs<PointerType>();
3087  if (T1PtrType && T2PtrType) {
3088    T1 = T1PtrType->getPointeeType();
3089    T2 = T2PtrType->getPointeeType();
3090    return true;
3091  }
3092
3093  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
3094                          *T2MPType = T2->getAs<MemberPointerType>();
3095  if (T1MPType && T2MPType &&
3096      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
3097                             QualType(T2MPType->getClass(), 0))) {
3098    T1 = T1MPType->getPointeeType();
3099    T2 = T2MPType->getPointeeType();
3100    return true;
3101  }
3102
3103  if (getLangOptions().ObjC1) {
3104    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
3105                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
3106    if (T1OPType && T2OPType) {
3107      T1 = T1OPType->getPointeeType();
3108      T2 = T2OPType->getPointeeType();
3109      return true;
3110    }
3111  }
3112
3113  // FIXME: Block pointers, too?
3114
3115  return false;
3116}
3117
3118DeclarationNameInfo
3119ASTContext::getNameForTemplate(TemplateName Name,
3120                               SourceLocation NameLoc) const {
3121  switch (Name.getKind()) {
3122  case TemplateName::QualifiedTemplate:
3123  case TemplateName::Template:
3124    // DNInfo work in progress: CHECKME: what about DNLoc?
3125    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
3126                               NameLoc);
3127
3128  case TemplateName::OverloadedTemplate: {
3129    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
3130    // DNInfo work in progress: CHECKME: what about DNLoc?
3131    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
3132  }
3133
3134  case TemplateName::DependentTemplate: {
3135    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3136    DeclarationName DName;
3137    if (DTN->isIdentifier()) {
3138      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
3139      return DeclarationNameInfo(DName, NameLoc);
3140    } else {
3141      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
3142      // DNInfo work in progress: FIXME: source locations?
3143      DeclarationNameLoc DNLoc;
3144      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
3145      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
3146      return DeclarationNameInfo(DName, NameLoc, DNLoc);
3147    }
3148  }
3149
3150  case TemplateName::SubstTemplateTemplateParm: {
3151    SubstTemplateTemplateParmStorage *subst
3152      = Name.getAsSubstTemplateTemplateParm();
3153    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
3154                               NameLoc);
3155  }
3156
3157  case TemplateName::SubstTemplateTemplateParmPack: {
3158    SubstTemplateTemplateParmPackStorage *subst
3159      = Name.getAsSubstTemplateTemplateParmPack();
3160    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
3161                               NameLoc);
3162  }
3163  }
3164
3165  llvm_unreachable("bad template name kind!");
3166}
3167
3168TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
3169  switch (Name.getKind()) {
3170  case TemplateName::QualifiedTemplate:
3171  case TemplateName::Template: {
3172    TemplateDecl *Template = Name.getAsTemplateDecl();
3173    if (TemplateTemplateParmDecl *TTP
3174          = dyn_cast<TemplateTemplateParmDecl>(Template))
3175      Template = getCanonicalTemplateTemplateParmDecl(TTP);
3176
3177    // The canonical template name is the canonical template declaration.
3178    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
3179  }
3180
3181  case TemplateName::OverloadedTemplate:
3182    llvm_unreachable("cannot canonicalize overloaded template");
3183
3184  case TemplateName::DependentTemplate: {
3185    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3186    assert(DTN && "Non-dependent template names must refer to template decls.");
3187    return DTN->CanonicalTemplateName;
3188  }
3189
3190  case TemplateName::SubstTemplateTemplateParm: {
3191    SubstTemplateTemplateParmStorage *subst
3192      = Name.getAsSubstTemplateTemplateParm();
3193    return getCanonicalTemplateName(subst->getReplacement());
3194  }
3195
3196  case TemplateName::SubstTemplateTemplateParmPack: {
3197    SubstTemplateTemplateParmPackStorage *subst
3198                                  = Name.getAsSubstTemplateTemplateParmPack();
3199    TemplateTemplateParmDecl *canonParameter
3200      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
3201    TemplateArgument canonArgPack
3202      = getCanonicalTemplateArgument(subst->getArgumentPack());
3203    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
3204  }
3205  }
3206
3207  llvm_unreachable("bad template name!");
3208}
3209
3210bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
3211  X = getCanonicalTemplateName(X);
3212  Y = getCanonicalTemplateName(Y);
3213  return X.getAsVoidPointer() == Y.getAsVoidPointer();
3214}
3215
3216TemplateArgument
3217ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
3218  switch (Arg.getKind()) {
3219    case TemplateArgument::Null:
3220      return Arg;
3221
3222    case TemplateArgument::Expression:
3223      return Arg;
3224
3225    case TemplateArgument::Declaration:
3226      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
3227
3228    case TemplateArgument::Template:
3229      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
3230
3231    case TemplateArgument::TemplateExpansion:
3232      return TemplateArgument(getCanonicalTemplateName(
3233                                         Arg.getAsTemplateOrTemplatePattern()),
3234                              Arg.getNumTemplateExpansions());
3235
3236    case TemplateArgument::Integral:
3237      return TemplateArgument(*Arg.getAsIntegral(),
3238                              getCanonicalType(Arg.getIntegralType()));
3239
3240    case TemplateArgument::Type:
3241      return TemplateArgument(getCanonicalType(Arg.getAsType()));
3242
3243    case TemplateArgument::Pack: {
3244      if (Arg.pack_size() == 0)
3245        return Arg;
3246
3247      TemplateArgument *CanonArgs
3248        = new (*this) TemplateArgument[Arg.pack_size()];
3249      unsigned Idx = 0;
3250      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
3251                                        AEnd = Arg.pack_end();
3252           A != AEnd; (void)++A, ++Idx)
3253        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
3254
3255      return TemplateArgument(CanonArgs, Arg.pack_size());
3256    }
3257  }
3258
3259  // Silence GCC warning
3260  llvm_unreachable("Unhandled template argument kind");
3261}
3262
3263NestedNameSpecifier *
3264ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
3265  if (!NNS)
3266    return 0;
3267
3268  switch (NNS->getKind()) {
3269  case NestedNameSpecifier::Identifier:
3270    // Canonicalize the prefix but keep the identifier the same.
3271    return NestedNameSpecifier::Create(*this,
3272                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
3273                                       NNS->getAsIdentifier());
3274
3275  case NestedNameSpecifier::Namespace:
3276    // A namespace is canonical; build a nested-name-specifier with
3277    // this namespace and no prefix.
3278    return NestedNameSpecifier::Create(*this, 0,
3279                                 NNS->getAsNamespace()->getOriginalNamespace());
3280
3281  case NestedNameSpecifier::NamespaceAlias:
3282    // A namespace is canonical; build a nested-name-specifier with
3283    // this namespace and no prefix.
3284    return NestedNameSpecifier::Create(*this, 0,
3285                                    NNS->getAsNamespaceAlias()->getNamespace()
3286                                                      ->getOriginalNamespace());
3287
3288  case NestedNameSpecifier::TypeSpec:
3289  case NestedNameSpecifier::TypeSpecWithTemplate: {
3290    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
3291
3292    // If we have some kind of dependent-named type (e.g., "typename T::type"),
3293    // break it apart into its prefix and identifier, then reconsititute those
3294    // as the canonical nested-name-specifier. This is required to canonicalize
3295    // a dependent nested-name-specifier involving typedefs of dependent-name
3296    // types, e.g.,
3297    //   typedef typename T::type T1;
3298    //   typedef typename T1::type T2;
3299    if (const DependentNameType *DNT = T->getAs<DependentNameType>()) {
3300      NestedNameSpecifier *Prefix
3301        = getCanonicalNestedNameSpecifier(DNT->getQualifier());
3302      return NestedNameSpecifier::Create(*this, Prefix,
3303                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
3304    }
3305
3306    // Do the same thing as above, but with dependent-named specializations.
3307    if (const DependentTemplateSpecializationType *DTST
3308          = T->getAs<DependentTemplateSpecializationType>()) {
3309      NestedNameSpecifier *Prefix
3310        = getCanonicalNestedNameSpecifier(DTST->getQualifier());
3311
3312      T = getDependentTemplateSpecializationType(DTST->getKeyword(),
3313                                                 Prefix, DTST->getIdentifier(),
3314                                                 DTST->getNumArgs(),
3315                                                 DTST->getArgs());
3316      T = getCanonicalType(T);
3317    }
3318
3319    return NestedNameSpecifier::Create(*this, 0, false,
3320                                       const_cast<Type*>(T.getTypePtr()));
3321  }
3322
3323  case NestedNameSpecifier::Global:
3324    // The global specifier is canonical and unique.
3325    return NNS;
3326  }
3327
3328  // Required to silence a GCC warning
3329  return 0;
3330}
3331
3332
3333const ArrayType *ASTContext::getAsArrayType(QualType T) const {
3334  // Handle the non-qualified case efficiently.
3335  if (!T.hasLocalQualifiers()) {
3336    // Handle the common positive case fast.
3337    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
3338      return AT;
3339  }
3340
3341  // Handle the common negative case fast.
3342  if (!isa<ArrayType>(T.getCanonicalType()))
3343    return 0;
3344
3345  // Apply any qualifiers from the array type to the element type.  This
3346  // implements C99 6.7.3p8: "If the specification of an array type includes
3347  // any type qualifiers, the element type is so qualified, not the array type."
3348
3349  // If we get here, we either have type qualifiers on the type, or we have
3350  // sugar such as a typedef in the way.  If we have type qualifiers on the type
3351  // we must propagate them down into the element type.
3352
3353  SplitQualType split = T.getSplitDesugaredType();
3354  Qualifiers qs = split.second;
3355
3356  // If we have a simple case, just return now.
3357  const ArrayType *ATy = dyn_cast<ArrayType>(split.first);
3358  if (ATy == 0 || qs.empty())
3359    return ATy;
3360
3361  // Otherwise, we have an array and we have qualifiers on it.  Push the
3362  // qualifiers into the array element type and return a new array type.
3363  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
3364
3365  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
3366    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
3367                                                CAT->getSizeModifier(),
3368                                           CAT->getIndexTypeCVRQualifiers()));
3369  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
3370    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
3371                                                  IAT->getSizeModifier(),
3372                                           IAT->getIndexTypeCVRQualifiers()));
3373
3374  if (const DependentSizedArrayType *DSAT
3375        = dyn_cast<DependentSizedArrayType>(ATy))
3376    return cast<ArrayType>(
3377                     getDependentSizedArrayType(NewEltTy,
3378                                                DSAT->getSizeExpr(),
3379                                                DSAT->getSizeModifier(),
3380                                              DSAT->getIndexTypeCVRQualifiers(),
3381                                                DSAT->getBracketsRange()));
3382
3383  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
3384  return cast<ArrayType>(getVariableArrayType(NewEltTy,
3385                                              VAT->getSizeExpr(),
3386                                              VAT->getSizeModifier(),
3387                                              VAT->getIndexTypeCVRQualifiers(),
3388                                              VAT->getBracketsRange()));
3389}
3390
3391QualType ASTContext::getAdjustedParameterType(QualType T) {
3392  // C99 6.7.5.3p7:
3393  //   A declaration of a parameter as "array of type" shall be
3394  //   adjusted to "qualified pointer to type", where the type
3395  //   qualifiers (if any) are those specified within the [ and ] of
3396  //   the array type derivation.
3397  if (T->isArrayType())
3398    return getArrayDecayedType(T);
3399
3400  // C99 6.7.5.3p8:
3401  //   A declaration of a parameter as "function returning type"
3402  //   shall be adjusted to "pointer to function returning type", as
3403  //   in 6.3.2.1.
3404  if (T->isFunctionType())
3405    return getPointerType(T);
3406
3407  return T;
3408}
3409
3410QualType ASTContext::getSignatureParameterType(QualType T) {
3411  T = getVariableArrayDecayedType(T);
3412  T = getAdjustedParameterType(T);
3413  return T.getUnqualifiedType();
3414}
3415
3416/// getArrayDecayedType - Return the properly qualified result of decaying the
3417/// specified array type to a pointer.  This operation is non-trivial when
3418/// handling typedefs etc.  The canonical type of "T" must be an array type,
3419/// this returns a pointer to a properly qualified element of the array.
3420///
3421/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
3422QualType ASTContext::getArrayDecayedType(QualType Ty) const {
3423  // Get the element type with 'getAsArrayType' so that we don't lose any
3424  // typedefs in the element type of the array.  This also handles propagation
3425  // of type qualifiers from the array type into the element type if present
3426  // (C99 6.7.3p8).
3427  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
3428  assert(PrettyArrayType && "Not an array type!");
3429
3430  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
3431
3432  // int x[restrict 4] ->  int *restrict
3433  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
3434}
3435
3436QualType ASTContext::getBaseElementType(const ArrayType *array) const {
3437  return getBaseElementType(array->getElementType());
3438}
3439
3440QualType ASTContext::getBaseElementType(QualType type) const {
3441  Qualifiers qs;
3442  while (true) {
3443    SplitQualType split = type.getSplitDesugaredType();
3444    const ArrayType *array = split.first->getAsArrayTypeUnsafe();
3445    if (!array) break;
3446
3447    type = array->getElementType();
3448    qs.addConsistentQualifiers(split.second);
3449  }
3450
3451  return getQualifiedType(type, qs);
3452}
3453
3454/// getConstantArrayElementCount - Returns number of constant array elements.
3455uint64_t
3456ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
3457  uint64_t ElementCount = 1;
3458  do {
3459    ElementCount *= CA->getSize().getZExtValue();
3460    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
3461  } while (CA);
3462  return ElementCount;
3463}
3464
3465/// getFloatingRank - Return a relative rank for floating point types.
3466/// This routine will assert if passed a built-in type that isn't a float.
3467static FloatingRank getFloatingRank(QualType T) {
3468  if (const ComplexType *CT = T->getAs<ComplexType>())
3469    return getFloatingRank(CT->getElementType());
3470
3471  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
3472  switch (T->getAs<BuiltinType>()->getKind()) {
3473  default: llvm_unreachable("getFloatingRank(): not a floating type");
3474  case BuiltinType::Float:      return FloatRank;
3475  case BuiltinType::Double:     return DoubleRank;
3476  case BuiltinType::LongDouble: return LongDoubleRank;
3477  }
3478}
3479
3480/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
3481/// point or a complex type (based on typeDomain/typeSize).
3482/// 'typeDomain' is a real floating point or complex type.
3483/// 'typeSize' is a real floating point or complex type.
3484QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
3485                                                       QualType Domain) const {
3486  FloatingRank EltRank = getFloatingRank(Size);
3487  if (Domain->isComplexType()) {
3488    switch (EltRank) {
3489    default: llvm_unreachable("getFloatingRank(): illegal value for rank");
3490    case FloatRank:      return FloatComplexTy;
3491    case DoubleRank:     return DoubleComplexTy;
3492    case LongDoubleRank: return LongDoubleComplexTy;
3493    }
3494  }
3495
3496  assert(Domain->isRealFloatingType() && "Unknown domain!");
3497  switch (EltRank) {
3498  default: llvm_unreachable("getFloatingRank(): illegal value for rank");
3499  case FloatRank:      return FloatTy;
3500  case DoubleRank:     return DoubleTy;
3501  case LongDoubleRank: return LongDoubleTy;
3502  }
3503}
3504
3505/// getFloatingTypeOrder - Compare the rank of the two specified floating
3506/// point types, ignoring the domain of the type (i.e. 'double' ==
3507/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3508/// LHS < RHS, return -1.
3509int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
3510  FloatingRank LHSR = getFloatingRank(LHS);
3511  FloatingRank RHSR = getFloatingRank(RHS);
3512
3513  if (LHSR == RHSR)
3514    return 0;
3515  if (LHSR > RHSR)
3516    return 1;
3517  return -1;
3518}
3519
3520/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
3521/// routine will assert if passed a built-in type that isn't an integer or enum,
3522/// or if it is not canonicalized.
3523unsigned ASTContext::getIntegerRank(const Type *T) const {
3524  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
3525  if (const EnumType* ET = dyn_cast<EnumType>(T))
3526    T = ET->getDecl()->getPromotionType().getTypePtr();
3527
3528  if (T->isSpecificBuiltinType(BuiltinType::WChar_S) ||
3529      T->isSpecificBuiltinType(BuiltinType::WChar_U))
3530    T = getFromTargetType(Target->getWCharType()).getTypePtr();
3531
3532  if (T->isSpecificBuiltinType(BuiltinType::Char16))
3533    T = getFromTargetType(Target->getChar16Type()).getTypePtr();
3534
3535  if (T->isSpecificBuiltinType(BuiltinType::Char32))
3536    T = getFromTargetType(Target->getChar32Type()).getTypePtr();
3537
3538  switch (cast<BuiltinType>(T)->getKind()) {
3539  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
3540  case BuiltinType::Bool:
3541    return 1 + (getIntWidth(BoolTy) << 3);
3542  case BuiltinType::Char_S:
3543  case BuiltinType::Char_U:
3544  case BuiltinType::SChar:
3545  case BuiltinType::UChar:
3546    return 2 + (getIntWidth(CharTy) << 3);
3547  case BuiltinType::Short:
3548  case BuiltinType::UShort:
3549    return 3 + (getIntWidth(ShortTy) << 3);
3550  case BuiltinType::Int:
3551  case BuiltinType::UInt:
3552    return 4 + (getIntWidth(IntTy) << 3);
3553  case BuiltinType::Long:
3554  case BuiltinType::ULong:
3555    return 5 + (getIntWidth(LongTy) << 3);
3556  case BuiltinType::LongLong:
3557  case BuiltinType::ULongLong:
3558    return 6 + (getIntWidth(LongLongTy) << 3);
3559  case BuiltinType::Int128:
3560  case BuiltinType::UInt128:
3561    return 7 + (getIntWidth(Int128Ty) << 3);
3562  }
3563}
3564
3565/// \brief Whether this is a promotable bitfield reference according
3566/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
3567///
3568/// \returns the type this bit-field will promote to, or NULL if no
3569/// promotion occurs.
3570QualType ASTContext::isPromotableBitField(Expr *E) const {
3571  if (E->isTypeDependent() || E->isValueDependent())
3572    return QualType();
3573
3574  FieldDecl *Field = E->getBitField();
3575  if (!Field)
3576    return QualType();
3577
3578  QualType FT = Field->getType();
3579
3580  llvm::APSInt BitWidthAP = Field->getBitWidth()->EvaluateAsInt(*this);
3581  uint64_t BitWidth = BitWidthAP.getZExtValue();
3582  uint64_t IntSize = getTypeSize(IntTy);
3583  // GCC extension compatibility: if the bit-field size is less than or equal
3584  // to the size of int, it gets promoted no matter what its type is.
3585  // For instance, unsigned long bf : 4 gets promoted to signed int.
3586  if (BitWidth < IntSize)
3587    return IntTy;
3588
3589  if (BitWidth == IntSize)
3590    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
3591
3592  // Types bigger than int are not subject to promotions, and therefore act
3593  // like the base type.
3594  // FIXME: This doesn't quite match what gcc does, but what gcc does here
3595  // is ridiculous.
3596  return QualType();
3597}
3598
3599/// getPromotedIntegerType - Returns the type that Promotable will
3600/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
3601/// integer type.
3602QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
3603  assert(!Promotable.isNull());
3604  assert(Promotable->isPromotableIntegerType());
3605  if (const EnumType *ET = Promotable->getAs<EnumType>())
3606    return ET->getDecl()->getPromotionType();
3607  if (Promotable->isSignedIntegerType())
3608    return IntTy;
3609  uint64_t PromotableSize = getTypeSize(Promotable);
3610  uint64_t IntSize = getTypeSize(IntTy);
3611  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3612  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3613}
3614
3615/// \brief Recurses in pointer/array types until it finds an objc retainable
3616/// type and returns its ownership.
3617Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
3618  while (!T.isNull()) {
3619    if (T.getObjCLifetime() != Qualifiers::OCL_None)
3620      return T.getObjCLifetime();
3621    if (T->isArrayType())
3622      T = getBaseElementType(T);
3623    else if (const PointerType *PT = T->getAs<PointerType>())
3624      T = PT->getPointeeType();
3625    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3626      T = RT->getPointeeType();
3627    else
3628      break;
3629  }
3630
3631  return Qualifiers::OCL_None;
3632}
3633
3634/// getIntegerTypeOrder - Returns the highest ranked integer type:
3635/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3636/// LHS < RHS, return -1.
3637int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
3638  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
3639  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
3640  if (LHSC == RHSC) return 0;
3641
3642  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3643  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3644
3645  unsigned LHSRank = getIntegerRank(LHSC);
3646  unsigned RHSRank = getIntegerRank(RHSC);
3647
3648  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3649    if (LHSRank == RHSRank) return 0;
3650    return LHSRank > RHSRank ? 1 : -1;
3651  }
3652
3653  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3654  if (LHSUnsigned) {
3655    // If the unsigned [LHS] type is larger, return it.
3656    if (LHSRank >= RHSRank)
3657      return 1;
3658
3659    // If the signed type can represent all values of the unsigned type, it
3660    // wins.  Because we are dealing with 2's complement and types that are
3661    // powers of two larger than each other, this is always safe.
3662    return -1;
3663  }
3664
3665  // If the unsigned [RHS] type is larger, return it.
3666  if (RHSRank >= LHSRank)
3667    return -1;
3668
3669  // If the signed type can represent all values of the unsigned type, it
3670  // wins.  Because we are dealing with 2's complement and types that are
3671  // powers of two larger than each other, this is always safe.
3672  return 1;
3673}
3674
3675static RecordDecl *
3676CreateRecordDecl(const ASTContext &Ctx, RecordDecl::TagKind TK,
3677                 DeclContext *DC, IdentifierInfo *Id) {
3678  SourceLocation Loc;
3679  if (Ctx.getLangOptions().CPlusPlus)
3680    return CXXRecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3681  else
3682    return RecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3683}
3684
3685// getCFConstantStringType - Return the type used for constant CFStrings.
3686QualType ASTContext::getCFConstantStringType() const {
3687  if (!CFConstantStringTypeDecl) {
3688    CFConstantStringTypeDecl =
3689      CreateRecordDecl(*this, TTK_Struct, TUDecl,
3690                       &Idents.get("NSConstantString"));
3691    CFConstantStringTypeDecl->startDefinition();
3692
3693    QualType FieldTypes[4];
3694
3695    // const int *isa;
3696    FieldTypes[0] = getPointerType(IntTy.withConst());
3697    // int flags;
3698    FieldTypes[1] = IntTy;
3699    // const char *str;
3700    FieldTypes[2] = getPointerType(CharTy.withConst());
3701    // long length;
3702    FieldTypes[3] = LongTy;
3703
3704    // Create fields
3705    for (unsigned i = 0; i < 4; ++i) {
3706      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3707                                           SourceLocation(),
3708                                           SourceLocation(), 0,
3709                                           FieldTypes[i], /*TInfo=*/0,
3710                                           /*BitWidth=*/0,
3711                                           /*Mutable=*/false,
3712                                           /*HasInit=*/false);
3713      Field->setAccess(AS_public);
3714      CFConstantStringTypeDecl->addDecl(Field);
3715    }
3716
3717    CFConstantStringTypeDecl->completeDefinition();
3718  }
3719
3720  return getTagDeclType(CFConstantStringTypeDecl);
3721}
3722
3723void ASTContext::setCFConstantStringType(QualType T) {
3724  const RecordType *Rec = T->getAs<RecordType>();
3725  assert(Rec && "Invalid CFConstantStringType");
3726  CFConstantStringTypeDecl = Rec->getDecl();
3727}
3728
3729QualType ASTContext::getBlockDescriptorType() const {
3730  if (BlockDescriptorType)
3731    return getTagDeclType(BlockDescriptorType);
3732
3733  RecordDecl *T;
3734  // FIXME: Needs the FlagAppleBlock bit.
3735  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3736                       &Idents.get("__block_descriptor"));
3737  T->startDefinition();
3738
3739  QualType FieldTypes[] = {
3740    UnsignedLongTy,
3741    UnsignedLongTy,
3742  };
3743
3744  const char *FieldNames[] = {
3745    "reserved",
3746    "Size"
3747  };
3748
3749  for (size_t i = 0; i < 2; ++i) {
3750    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3751                                         SourceLocation(),
3752                                         &Idents.get(FieldNames[i]),
3753                                         FieldTypes[i], /*TInfo=*/0,
3754                                         /*BitWidth=*/0,
3755                                         /*Mutable=*/false,
3756                                         /*HasInit=*/false);
3757    Field->setAccess(AS_public);
3758    T->addDecl(Field);
3759  }
3760
3761  T->completeDefinition();
3762
3763  BlockDescriptorType = T;
3764
3765  return getTagDeclType(BlockDescriptorType);
3766}
3767
3768QualType ASTContext::getBlockDescriptorExtendedType() const {
3769  if (BlockDescriptorExtendedType)
3770    return getTagDeclType(BlockDescriptorExtendedType);
3771
3772  RecordDecl *T;
3773  // FIXME: Needs the FlagAppleBlock bit.
3774  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3775                       &Idents.get("__block_descriptor_withcopydispose"));
3776  T->startDefinition();
3777
3778  QualType FieldTypes[] = {
3779    UnsignedLongTy,
3780    UnsignedLongTy,
3781    getPointerType(VoidPtrTy),
3782    getPointerType(VoidPtrTy)
3783  };
3784
3785  const char *FieldNames[] = {
3786    "reserved",
3787    "Size",
3788    "CopyFuncPtr",
3789    "DestroyFuncPtr"
3790  };
3791
3792  for (size_t i = 0; i < 4; ++i) {
3793    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3794                                         SourceLocation(),
3795                                         &Idents.get(FieldNames[i]),
3796                                         FieldTypes[i], /*TInfo=*/0,
3797                                         /*BitWidth=*/0,
3798                                         /*Mutable=*/false,
3799                                         /*HasInit=*/false);
3800    Field->setAccess(AS_public);
3801    T->addDecl(Field);
3802  }
3803
3804  T->completeDefinition();
3805
3806  BlockDescriptorExtendedType = T;
3807
3808  return getTagDeclType(BlockDescriptorExtendedType);
3809}
3810
3811bool ASTContext::BlockRequiresCopying(QualType Ty) const {
3812  if (Ty->isObjCRetainableType())
3813    return true;
3814  if (getLangOptions().CPlusPlus) {
3815    if (const RecordType *RT = Ty->getAs<RecordType>()) {
3816      CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
3817      return RD->hasConstCopyConstructor();
3818
3819    }
3820  }
3821  return false;
3822}
3823
3824QualType
3825ASTContext::BuildByRefType(StringRef DeclName, QualType Ty) const {
3826  //  type = struct __Block_byref_1_X {
3827  //    void *__isa;
3828  //    struct __Block_byref_1_X *__forwarding;
3829  //    unsigned int __flags;
3830  //    unsigned int __size;
3831  //    void *__copy_helper;            // as needed
3832  //    void *__destroy_help            // as needed
3833  //    int X;
3834  //  } *
3835
3836  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3837
3838  // FIXME: Move up
3839  llvm::SmallString<36> Name;
3840  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3841                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3842  RecordDecl *T;
3843  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, &Idents.get(Name.str()));
3844  T->startDefinition();
3845  QualType Int32Ty = IntTy;
3846  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3847  QualType FieldTypes[] = {
3848    getPointerType(VoidPtrTy),
3849    getPointerType(getTagDeclType(T)),
3850    Int32Ty,
3851    Int32Ty,
3852    getPointerType(VoidPtrTy),
3853    getPointerType(VoidPtrTy),
3854    Ty
3855  };
3856
3857  StringRef FieldNames[] = {
3858    "__isa",
3859    "__forwarding",
3860    "__flags",
3861    "__size",
3862    "__copy_helper",
3863    "__destroy_helper",
3864    DeclName,
3865  };
3866
3867  for (size_t i = 0; i < 7; ++i) {
3868    if (!HasCopyAndDispose && i >=4 && i <= 5)
3869      continue;
3870    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3871                                         SourceLocation(),
3872                                         &Idents.get(FieldNames[i]),
3873                                         FieldTypes[i], /*TInfo=*/0,
3874                                         /*BitWidth=*/0, /*Mutable=*/false,
3875                                         /*HasInit=*/false);
3876    Field->setAccess(AS_public);
3877    T->addDecl(Field);
3878  }
3879
3880  T->completeDefinition();
3881
3882  return getPointerType(getTagDeclType(T));
3883}
3884
3885TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
3886  if (!ObjCInstanceTypeDecl)
3887    ObjCInstanceTypeDecl = TypedefDecl::Create(*this,
3888                                               getTranslationUnitDecl(),
3889                                               SourceLocation(),
3890                                               SourceLocation(),
3891                                               &Idents.get("instancetype"),
3892                                     getTrivialTypeSourceInfo(getObjCIdType()));
3893  return ObjCInstanceTypeDecl;
3894}
3895
3896// This returns true if a type has been typedefed to BOOL:
3897// typedef <type> BOOL;
3898static bool isTypeTypedefedAsBOOL(QualType T) {
3899  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3900    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3901      return II->isStr("BOOL");
3902
3903  return false;
3904}
3905
3906/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3907/// purpose.
3908CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
3909  if (!type->isIncompleteArrayType() && type->isIncompleteType())
3910    return CharUnits::Zero();
3911
3912  CharUnits sz = getTypeSizeInChars(type);
3913
3914  // Make all integer and enum types at least as large as an int
3915  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3916    sz = std::max(sz, getTypeSizeInChars(IntTy));
3917  // Treat arrays as pointers, since that's how they're passed in.
3918  else if (type->isArrayType())
3919    sz = getTypeSizeInChars(VoidPtrTy);
3920  return sz;
3921}
3922
3923static inline
3924std::string charUnitsToString(const CharUnits &CU) {
3925  return llvm::itostr(CU.getQuantity());
3926}
3927
3928/// getObjCEncodingForBlock - Return the encoded type for this block
3929/// declaration.
3930std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
3931  std::string S;
3932
3933  const BlockDecl *Decl = Expr->getBlockDecl();
3934  QualType BlockTy =
3935      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3936  // Encode result type.
3937  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3938  // Compute size of all parameters.
3939  // Start with computing size of a pointer in number of bytes.
3940  // FIXME: There might(should) be a better way of doing this computation!
3941  SourceLocation Loc;
3942  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3943  CharUnits ParmOffset = PtrSize;
3944  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3945       E = Decl->param_end(); PI != E; ++PI) {
3946    QualType PType = (*PI)->getType();
3947    CharUnits sz = getObjCEncodingTypeSize(PType);
3948    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3949    ParmOffset += sz;
3950  }
3951  // Size of the argument frame
3952  S += charUnitsToString(ParmOffset);
3953  // Block pointer and offset.
3954  S += "@?0";
3955
3956  // Argument types.
3957  ParmOffset = PtrSize;
3958  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3959       Decl->param_end(); PI != E; ++PI) {
3960    ParmVarDecl *PVDecl = *PI;
3961    QualType PType = PVDecl->getOriginalType();
3962    if (const ArrayType *AT =
3963          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3964      // Use array's original type only if it has known number of
3965      // elements.
3966      if (!isa<ConstantArrayType>(AT))
3967        PType = PVDecl->getType();
3968    } else if (PType->isFunctionType())
3969      PType = PVDecl->getType();
3970    getObjCEncodingForType(PType, S);
3971    S += charUnitsToString(ParmOffset);
3972    ParmOffset += getObjCEncodingTypeSize(PType);
3973  }
3974
3975  return S;
3976}
3977
3978bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
3979                                                std::string& S) {
3980  // Encode result type.
3981  getObjCEncodingForType(Decl->getResultType(), S);
3982  CharUnits ParmOffset;
3983  // Compute size of all parameters.
3984  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
3985       E = Decl->param_end(); PI != E; ++PI) {
3986    QualType PType = (*PI)->getType();
3987    CharUnits sz = getObjCEncodingTypeSize(PType);
3988    if (sz.isZero())
3989      return true;
3990
3991    assert (sz.isPositive() &&
3992        "getObjCEncodingForFunctionDecl - Incomplete param type");
3993    ParmOffset += sz;
3994  }
3995  S += charUnitsToString(ParmOffset);
3996  ParmOffset = CharUnits::Zero();
3997
3998  // Argument types.
3999  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4000       E = Decl->param_end(); PI != E; ++PI) {
4001    ParmVarDecl *PVDecl = *PI;
4002    QualType PType = PVDecl->getOriginalType();
4003    if (const ArrayType *AT =
4004          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4005      // Use array's original type only if it has known number of
4006      // elements.
4007      if (!isa<ConstantArrayType>(AT))
4008        PType = PVDecl->getType();
4009    } else if (PType->isFunctionType())
4010      PType = PVDecl->getType();
4011    getObjCEncodingForType(PType, S);
4012    S += charUnitsToString(ParmOffset);
4013    ParmOffset += getObjCEncodingTypeSize(PType);
4014  }
4015
4016  return false;
4017}
4018
4019/// getObjCEncodingForMethodDecl - Return the encoded type for this method
4020/// declaration.
4021bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
4022                                              std::string& S) const {
4023  // FIXME: This is not very efficient.
4024  // Encode type qualifer, 'in', 'inout', etc. for the return type.
4025  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
4026  // Encode result type.
4027  getObjCEncodingForType(Decl->getResultType(), S);
4028  // Compute size of all parameters.
4029  // Start with computing size of a pointer in number of bytes.
4030  // FIXME: There might(should) be a better way of doing this computation!
4031  SourceLocation Loc;
4032  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4033  // The first two arguments (self and _cmd) are pointers; account for
4034  // their size.
4035  CharUnits ParmOffset = 2 * PtrSize;
4036  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4037       E = Decl->sel_param_end(); PI != E; ++PI) {
4038    QualType PType = (*PI)->getType();
4039    CharUnits sz = getObjCEncodingTypeSize(PType);
4040    if (sz.isZero())
4041      return true;
4042
4043    assert (sz.isPositive() &&
4044        "getObjCEncodingForMethodDecl - Incomplete param type");
4045    ParmOffset += sz;
4046  }
4047  S += charUnitsToString(ParmOffset);
4048  S += "@0:";
4049  S += charUnitsToString(PtrSize);
4050
4051  // Argument types.
4052  ParmOffset = 2 * PtrSize;
4053  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4054       E = Decl->sel_param_end(); PI != E; ++PI) {
4055    const ParmVarDecl *PVDecl = *PI;
4056    QualType PType = PVDecl->getOriginalType();
4057    if (const ArrayType *AT =
4058          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4059      // Use array's original type only if it has known number of
4060      // elements.
4061      if (!isa<ConstantArrayType>(AT))
4062        PType = PVDecl->getType();
4063    } else if (PType->isFunctionType())
4064      PType = PVDecl->getType();
4065    // Process argument qualifiers for user supplied arguments; such as,
4066    // 'in', 'inout', etc.
4067    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
4068    getObjCEncodingForType(PType, S);
4069    S += charUnitsToString(ParmOffset);
4070    ParmOffset += getObjCEncodingTypeSize(PType);
4071  }
4072
4073  return false;
4074}
4075
4076/// getObjCEncodingForPropertyDecl - Return the encoded type for this
4077/// property declaration. If non-NULL, Container must be either an
4078/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
4079/// NULL when getting encodings for protocol properties.
4080/// Property attributes are stored as a comma-delimited C string. The simple
4081/// attributes readonly and bycopy are encoded as single characters. The
4082/// parametrized attributes, getter=name, setter=name, and ivar=name, are
4083/// encoded as single characters, followed by an identifier. Property types
4084/// are also encoded as a parametrized attribute. The characters used to encode
4085/// these attributes are defined by the following enumeration:
4086/// @code
4087/// enum PropertyAttributes {
4088/// kPropertyReadOnly = 'R',   // property is read-only.
4089/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
4090/// kPropertyByref = '&',  // property is a reference to the value last assigned
4091/// kPropertyDynamic = 'D',    // property is dynamic
4092/// kPropertyGetter = 'G',     // followed by getter selector name
4093/// kPropertySetter = 'S',     // followed by setter selector name
4094/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
4095/// kPropertyType = 't'              // followed by old-style type encoding.
4096/// kPropertyWeak = 'W'              // 'weak' property
4097/// kPropertyStrong = 'P'            // property GC'able
4098/// kPropertyNonAtomic = 'N'         // property non-atomic
4099/// };
4100/// @endcode
4101void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
4102                                                const Decl *Container,
4103                                                std::string& S) const {
4104  // Collect information from the property implementation decl(s).
4105  bool Dynamic = false;
4106  ObjCPropertyImplDecl *SynthesizePID = 0;
4107
4108  // FIXME: Duplicated code due to poor abstraction.
4109  if (Container) {
4110    if (const ObjCCategoryImplDecl *CID =
4111        dyn_cast<ObjCCategoryImplDecl>(Container)) {
4112      for (ObjCCategoryImplDecl::propimpl_iterator
4113             i = CID->propimpl_begin(), e = CID->propimpl_end();
4114           i != e; ++i) {
4115        ObjCPropertyImplDecl *PID = *i;
4116        if (PID->getPropertyDecl() == PD) {
4117          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4118            Dynamic = true;
4119          } else {
4120            SynthesizePID = PID;
4121          }
4122        }
4123      }
4124    } else {
4125      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
4126      for (ObjCCategoryImplDecl::propimpl_iterator
4127             i = OID->propimpl_begin(), e = OID->propimpl_end();
4128           i != e; ++i) {
4129        ObjCPropertyImplDecl *PID = *i;
4130        if (PID->getPropertyDecl() == PD) {
4131          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4132            Dynamic = true;
4133          } else {
4134            SynthesizePID = PID;
4135          }
4136        }
4137      }
4138    }
4139  }
4140
4141  // FIXME: This is not very efficient.
4142  S = "T";
4143
4144  // Encode result type.
4145  // GCC has some special rules regarding encoding of properties which
4146  // closely resembles encoding of ivars.
4147  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
4148                             true /* outermost type */,
4149                             true /* encoding for property */);
4150
4151  if (PD->isReadOnly()) {
4152    S += ",R";
4153  } else {
4154    switch (PD->getSetterKind()) {
4155    case ObjCPropertyDecl::Assign: break;
4156    case ObjCPropertyDecl::Copy:   S += ",C"; break;
4157    case ObjCPropertyDecl::Retain: S += ",&"; break;
4158    case ObjCPropertyDecl::Weak:   S += ",W"; break;
4159    }
4160  }
4161
4162  // It really isn't clear at all what this means, since properties
4163  // are "dynamic by default".
4164  if (Dynamic)
4165    S += ",D";
4166
4167  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
4168    S += ",N";
4169
4170  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
4171    S += ",G";
4172    S += PD->getGetterName().getAsString();
4173  }
4174
4175  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
4176    S += ",S";
4177    S += PD->getSetterName().getAsString();
4178  }
4179
4180  if (SynthesizePID) {
4181    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
4182    S += ",V";
4183    S += OID->getNameAsString();
4184  }
4185
4186  // FIXME: OBJCGC: weak & strong
4187}
4188
4189/// getLegacyIntegralTypeEncoding -
4190/// Another legacy compatibility encoding: 32-bit longs are encoded as
4191/// 'l' or 'L' , but not always.  For typedefs, we need to use
4192/// 'i' or 'I' instead if encoding a struct field, or a pointer!
4193///
4194void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
4195  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
4196    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
4197      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
4198        PointeeTy = UnsignedIntTy;
4199      else
4200        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
4201          PointeeTy = IntTy;
4202    }
4203  }
4204}
4205
4206void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
4207                                        const FieldDecl *Field) const {
4208  // We follow the behavior of gcc, expanding structures which are
4209  // directly pointed to, and expanding embedded structures. Note that
4210  // these rules are sufficient to prevent recursive encoding of the
4211  // same type.
4212  getObjCEncodingForTypeImpl(T, S, true, true, Field,
4213                             true /* outermost type */);
4214}
4215
4216static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
4217    switch (T->getAs<BuiltinType>()->getKind()) {
4218    default: llvm_unreachable("Unhandled builtin type kind");
4219    case BuiltinType::Void:       return 'v';
4220    case BuiltinType::Bool:       return 'B';
4221    case BuiltinType::Char_U:
4222    case BuiltinType::UChar:      return 'C';
4223    case BuiltinType::UShort:     return 'S';
4224    case BuiltinType::UInt:       return 'I';
4225    case BuiltinType::ULong:
4226        return C->getIntWidth(T) == 32 ? 'L' : 'Q';
4227    case BuiltinType::UInt128:    return 'T';
4228    case BuiltinType::ULongLong:  return 'Q';
4229    case BuiltinType::Char_S:
4230    case BuiltinType::SChar:      return 'c';
4231    case BuiltinType::Short:      return 's';
4232    case BuiltinType::WChar_S:
4233    case BuiltinType::WChar_U:
4234    case BuiltinType::Int:        return 'i';
4235    case BuiltinType::Long:
4236      return C->getIntWidth(T) == 32 ? 'l' : 'q';
4237    case BuiltinType::LongLong:   return 'q';
4238    case BuiltinType::Int128:     return 't';
4239    case BuiltinType::Float:      return 'f';
4240    case BuiltinType::Double:     return 'd';
4241    case BuiltinType::LongDouble: return 'D';
4242    }
4243}
4244
4245static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
4246  EnumDecl *Enum = ET->getDecl();
4247
4248  // The encoding of an non-fixed enum type is always 'i', regardless of size.
4249  if (!Enum->isFixed())
4250    return 'i';
4251
4252  // The encoding of a fixed enum type matches its fixed underlying type.
4253  return ObjCEncodingForPrimitiveKind(C, Enum->getIntegerType());
4254}
4255
4256static void EncodeBitField(const ASTContext *Ctx, std::string& S,
4257                           QualType T, const FieldDecl *FD) {
4258  const Expr *E = FD->getBitWidth();
4259  assert(E && "bitfield width not there - getObjCEncodingForTypeImpl");
4260  S += 'b';
4261  // The NeXT runtime encodes bit fields as b followed by the number of bits.
4262  // The GNU runtime requires more information; bitfields are encoded as b,
4263  // then the offset (in bits) of the first element, then the type of the
4264  // bitfield, then the size in bits.  For example, in this structure:
4265  //
4266  // struct
4267  // {
4268  //    int integer;
4269  //    int flags:2;
4270  // };
4271  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
4272  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
4273  // information is not especially sensible, but we're stuck with it for
4274  // compatibility with GCC, although providing it breaks anything that
4275  // actually uses runtime introspection and wants to work on both runtimes...
4276  if (!Ctx->getLangOptions().NeXTRuntime) {
4277    const RecordDecl *RD = FD->getParent();
4278    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
4279    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
4280    if (const EnumType *ET = T->getAs<EnumType>())
4281      S += ObjCEncodingForEnumType(Ctx, ET);
4282    else
4283      S += ObjCEncodingForPrimitiveKind(Ctx, T);
4284  }
4285  unsigned N = E->EvaluateAsInt(*Ctx).getZExtValue();
4286  S += llvm::utostr(N);
4287}
4288
4289// FIXME: Use SmallString for accumulating string.
4290void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
4291                                            bool ExpandPointedToStructures,
4292                                            bool ExpandStructures,
4293                                            const FieldDecl *FD,
4294                                            bool OutermostType,
4295                                            bool EncodingProperty,
4296                                            bool StructField) const {
4297  if (T->getAs<BuiltinType>()) {
4298    if (FD && FD->isBitField())
4299      return EncodeBitField(this, S, T, FD);
4300    S += ObjCEncodingForPrimitiveKind(this, T);
4301    return;
4302  }
4303
4304  if (const ComplexType *CT = T->getAs<ComplexType>()) {
4305    S += 'j';
4306    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
4307                               false);
4308    return;
4309  }
4310
4311  // encoding for pointer or r3eference types.
4312  QualType PointeeTy;
4313  if (const PointerType *PT = T->getAs<PointerType>()) {
4314    if (PT->isObjCSelType()) {
4315      S += ':';
4316      return;
4317    }
4318    PointeeTy = PT->getPointeeType();
4319  }
4320  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4321    PointeeTy = RT->getPointeeType();
4322  if (!PointeeTy.isNull()) {
4323    bool isReadOnly = false;
4324    // For historical/compatibility reasons, the read-only qualifier of the
4325    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
4326    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
4327    // Also, do not emit the 'r' for anything but the outermost type!
4328    if (isa<TypedefType>(T.getTypePtr())) {
4329      if (OutermostType && T.isConstQualified()) {
4330        isReadOnly = true;
4331        S += 'r';
4332      }
4333    } else if (OutermostType) {
4334      QualType P = PointeeTy;
4335      while (P->getAs<PointerType>())
4336        P = P->getAs<PointerType>()->getPointeeType();
4337      if (P.isConstQualified()) {
4338        isReadOnly = true;
4339        S += 'r';
4340      }
4341    }
4342    if (isReadOnly) {
4343      // Another legacy compatibility encoding. Some ObjC qualifier and type
4344      // combinations need to be rearranged.
4345      // Rewrite "in const" from "nr" to "rn"
4346      if (StringRef(S).endswith("nr"))
4347        S.replace(S.end()-2, S.end(), "rn");
4348    }
4349
4350    if (PointeeTy->isCharType()) {
4351      // char pointer types should be encoded as '*' unless it is a
4352      // type that has been typedef'd to 'BOOL'.
4353      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
4354        S += '*';
4355        return;
4356      }
4357    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
4358      // GCC binary compat: Need to convert "struct objc_class *" to "#".
4359      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
4360        S += '#';
4361        return;
4362      }
4363      // GCC binary compat: Need to convert "struct objc_object *" to "@".
4364      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
4365        S += '@';
4366        return;
4367      }
4368      // fall through...
4369    }
4370    S += '^';
4371    getLegacyIntegralTypeEncoding(PointeeTy);
4372
4373    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
4374                               NULL);
4375    return;
4376  }
4377
4378  if (const ArrayType *AT =
4379      // Ignore type qualifiers etc.
4380        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
4381    if (isa<IncompleteArrayType>(AT) && !StructField) {
4382      // Incomplete arrays are encoded as a pointer to the array element.
4383      S += '^';
4384
4385      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4386                                 false, ExpandStructures, FD);
4387    } else {
4388      S += '[';
4389
4390      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
4391        if (getTypeSize(CAT->getElementType()) == 0)
4392          S += '0';
4393        else
4394          S += llvm::utostr(CAT->getSize().getZExtValue());
4395      } else {
4396        //Variable length arrays are encoded as a regular array with 0 elements.
4397        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
4398               "Unknown array type!");
4399        S += '0';
4400      }
4401
4402      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4403                                 false, ExpandStructures, FD);
4404      S += ']';
4405    }
4406    return;
4407  }
4408
4409  if (T->getAs<FunctionType>()) {
4410    S += '?';
4411    return;
4412  }
4413
4414  if (const RecordType *RTy = T->getAs<RecordType>()) {
4415    RecordDecl *RDecl = RTy->getDecl();
4416    S += RDecl->isUnion() ? '(' : '{';
4417    // Anonymous structures print as '?'
4418    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
4419      S += II->getName();
4420      if (ClassTemplateSpecializationDecl *Spec
4421          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
4422        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
4423        std::string TemplateArgsStr
4424          = TemplateSpecializationType::PrintTemplateArgumentList(
4425                                            TemplateArgs.data(),
4426                                            TemplateArgs.size(),
4427                                            (*this).getPrintingPolicy());
4428
4429        S += TemplateArgsStr;
4430      }
4431    } else {
4432      S += '?';
4433    }
4434    if (ExpandStructures) {
4435      S += '=';
4436      if (!RDecl->isUnion()) {
4437        getObjCEncodingForStructureImpl(RDecl, S, FD);
4438      } else {
4439        for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4440                                     FieldEnd = RDecl->field_end();
4441             Field != FieldEnd; ++Field) {
4442          if (FD) {
4443            S += '"';
4444            S += Field->getNameAsString();
4445            S += '"';
4446          }
4447
4448          // Special case bit-fields.
4449          if (Field->isBitField()) {
4450            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
4451                                       (*Field));
4452          } else {
4453            QualType qt = Field->getType();
4454            getLegacyIntegralTypeEncoding(qt);
4455            getObjCEncodingForTypeImpl(qt, S, false, true,
4456                                       FD, /*OutermostType*/false,
4457                                       /*EncodingProperty*/false,
4458                                       /*StructField*/true);
4459          }
4460        }
4461      }
4462    }
4463    S += RDecl->isUnion() ? ')' : '}';
4464    return;
4465  }
4466
4467  if (const EnumType *ET = T->getAs<EnumType>()) {
4468    if (FD && FD->isBitField())
4469      EncodeBitField(this, S, T, FD);
4470    else
4471      S += ObjCEncodingForEnumType(this, ET);
4472    return;
4473  }
4474
4475  if (T->isBlockPointerType()) {
4476    S += "@?"; // Unlike a pointer-to-function, which is "^?".
4477    return;
4478  }
4479
4480  // Ignore protocol qualifiers when mangling at this level.
4481  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
4482    T = OT->getBaseType();
4483
4484  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
4485    // @encode(class_name)
4486    ObjCInterfaceDecl *OI = OIT->getDecl();
4487    S += '{';
4488    const IdentifierInfo *II = OI->getIdentifier();
4489    S += II->getName();
4490    S += '=';
4491    SmallVector<const ObjCIvarDecl*, 32> Ivars;
4492    DeepCollectObjCIvars(OI, true, Ivars);
4493    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
4494      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
4495      if (Field->isBitField())
4496        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
4497      else
4498        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
4499    }
4500    S += '}';
4501    return;
4502  }
4503
4504  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
4505    if (OPT->isObjCIdType()) {
4506      S += '@';
4507      return;
4508    }
4509
4510    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
4511      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
4512      // Since this is a binary compatibility issue, need to consult with runtime
4513      // folks. Fortunately, this is a *very* obsure construct.
4514      S += '#';
4515      return;
4516    }
4517
4518    if (OPT->isObjCQualifiedIdType()) {
4519      getObjCEncodingForTypeImpl(getObjCIdType(), S,
4520                                 ExpandPointedToStructures,
4521                                 ExpandStructures, FD);
4522      if (FD || EncodingProperty) {
4523        // Note that we do extended encoding of protocol qualifer list
4524        // Only when doing ivar or property encoding.
4525        S += '"';
4526        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4527             E = OPT->qual_end(); I != E; ++I) {
4528          S += '<';
4529          S += (*I)->getNameAsString();
4530          S += '>';
4531        }
4532        S += '"';
4533      }
4534      return;
4535    }
4536
4537    QualType PointeeTy = OPT->getPointeeType();
4538    if (!EncodingProperty &&
4539        isa<TypedefType>(PointeeTy.getTypePtr())) {
4540      // Another historical/compatibility reason.
4541      // We encode the underlying type which comes out as
4542      // {...};
4543      S += '^';
4544      getObjCEncodingForTypeImpl(PointeeTy, S,
4545                                 false, ExpandPointedToStructures,
4546                                 NULL);
4547      return;
4548    }
4549
4550    S += '@';
4551    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
4552      S += '"';
4553      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4554      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4555           E = OPT->qual_end(); I != E; ++I) {
4556        S += '<';
4557        S += (*I)->getNameAsString();
4558        S += '>';
4559      }
4560      S += '"';
4561    }
4562    return;
4563  }
4564
4565  // gcc just blithely ignores member pointers.
4566  // TODO: maybe there should be a mangling for these
4567  if (T->getAs<MemberPointerType>())
4568    return;
4569
4570  if (T->isVectorType()) {
4571    // This matches gcc's encoding, even though technically it is
4572    // insufficient.
4573    // FIXME. We should do a better job than gcc.
4574    return;
4575  }
4576
4577  llvm_unreachable("@encode for type not implemented!");
4578}
4579
4580void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
4581                                                 std::string &S,
4582                                                 const FieldDecl *FD,
4583                                                 bool includeVBases) const {
4584  assert(RDecl && "Expected non-null RecordDecl");
4585  assert(!RDecl->isUnion() && "Should not be called for unions");
4586  if (!RDecl->getDefinition())
4587    return;
4588
4589  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
4590  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
4591  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
4592
4593  if (CXXRec) {
4594    for (CXXRecordDecl::base_class_iterator
4595           BI = CXXRec->bases_begin(),
4596           BE = CXXRec->bases_end(); BI != BE; ++BI) {
4597      if (!BI->isVirtual()) {
4598        CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4599        if (base->isEmpty())
4600          continue;
4601        uint64_t offs = layout.getBaseClassOffsetInBits(base);
4602        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4603                                  std::make_pair(offs, base));
4604      }
4605    }
4606  }
4607
4608  unsigned i = 0;
4609  for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4610                               FieldEnd = RDecl->field_end();
4611       Field != FieldEnd; ++Field, ++i) {
4612    uint64_t offs = layout.getFieldOffset(i);
4613    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4614                              std::make_pair(offs, *Field));
4615  }
4616
4617  if (CXXRec && includeVBases) {
4618    for (CXXRecordDecl::base_class_iterator
4619           BI = CXXRec->vbases_begin(),
4620           BE = CXXRec->vbases_end(); BI != BE; ++BI) {
4621      CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4622      if (base->isEmpty())
4623        continue;
4624      uint64_t offs = layout.getVBaseClassOffsetInBits(base);
4625      if (FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
4626        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
4627                                  std::make_pair(offs, base));
4628    }
4629  }
4630
4631  CharUnits size;
4632  if (CXXRec) {
4633    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
4634  } else {
4635    size = layout.getSize();
4636  }
4637
4638  uint64_t CurOffs = 0;
4639  std::multimap<uint64_t, NamedDecl *>::iterator
4640    CurLayObj = FieldOrBaseOffsets.begin();
4641
4642  if ((CurLayObj != FieldOrBaseOffsets.end() && CurLayObj->first != 0) ||
4643      (CurLayObj == FieldOrBaseOffsets.end() &&
4644         CXXRec && CXXRec->isDynamicClass())) {
4645    assert(CXXRec && CXXRec->isDynamicClass() &&
4646           "Offset 0 was empty but no VTable ?");
4647    if (FD) {
4648      S += "\"_vptr$";
4649      std::string recname = CXXRec->getNameAsString();
4650      if (recname.empty()) recname = "?";
4651      S += recname;
4652      S += '"';
4653    }
4654    S += "^^?";
4655    CurOffs += getTypeSize(VoidPtrTy);
4656  }
4657
4658  if (!RDecl->hasFlexibleArrayMember()) {
4659    // Mark the end of the structure.
4660    uint64_t offs = toBits(size);
4661    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4662                              std::make_pair(offs, (NamedDecl*)0));
4663  }
4664
4665  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
4666    assert(CurOffs <= CurLayObj->first);
4667
4668    if (CurOffs < CurLayObj->first) {
4669      uint64_t padding = CurLayObj->first - CurOffs;
4670      // FIXME: There doesn't seem to be a way to indicate in the encoding that
4671      // packing/alignment of members is different that normal, in which case
4672      // the encoding will be out-of-sync with the real layout.
4673      // If the runtime switches to just consider the size of types without
4674      // taking into account alignment, we could make padding explicit in the
4675      // encoding (e.g. using arrays of chars). The encoding strings would be
4676      // longer then though.
4677      CurOffs += padding;
4678    }
4679
4680    NamedDecl *dcl = CurLayObj->second;
4681    if (dcl == 0)
4682      break; // reached end of structure.
4683
4684    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
4685      // We expand the bases without their virtual bases since those are going
4686      // in the initial structure. Note that this differs from gcc which
4687      // expands virtual bases each time one is encountered in the hierarchy,
4688      // making the encoding type bigger than it really is.
4689      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false);
4690      assert(!base->isEmpty());
4691      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
4692    } else {
4693      FieldDecl *field = cast<FieldDecl>(dcl);
4694      if (FD) {
4695        S += '"';
4696        S += field->getNameAsString();
4697        S += '"';
4698      }
4699
4700      if (field->isBitField()) {
4701        EncodeBitField(this, S, field->getType(), field);
4702        CurOffs += field->getBitWidth()->EvaluateAsInt(*this).getZExtValue();
4703      } else {
4704        QualType qt = field->getType();
4705        getLegacyIntegralTypeEncoding(qt);
4706        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
4707                                   /*OutermostType*/false,
4708                                   /*EncodingProperty*/false,
4709                                   /*StructField*/true);
4710        CurOffs += getTypeSize(field->getType());
4711      }
4712    }
4713  }
4714}
4715
4716void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4717                                                 std::string& S) const {
4718  if (QT & Decl::OBJC_TQ_In)
4719    S += 'n';
4720  if (QT & Decl::OBJC_TQ_Inout)
4721    S += 'N';
4722  if (QT & Decl::OBJC_TQ_Out)
4723    S += 'o';
4724  if (QT & Decl::OBJC_TQ_Bycopy)
4725    S += 'O';
4726  if (QT & Decl::OBJC_TQ_Byref)
4727    S += 'R';
4728  if (QT & Decl::OBJC_TQ_Oneway)
4729    S += 'V';
4730}
4731
4732void ASTContext::setBuiltinVaListType(QualType T) {
4733  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4734
4735  BuiltinVaListType = T;
4736}
4737
4738TypedefDecl *ASTContext::getObjCIdDecl() const {
4739  if (!ObjCIdDecl) {
4740    QualType T = getObjCObjectType(ObjCBuiltinIdTy, 0, 0);
4741    T = getObjCObjectPointerType(T);
4742    TypeSourceInfo *IdInfo = getTrivialTypeSourceInfo(T);
4743    ObjCIdDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4744                                     getTranslationUnitDecl(),
4745                                     SourceLocation(), SourceLocation(),
4746                                     &Idents.get("id"), IdInfo);
4747  }
4748
4749  return ObjCIdDecl;
4750}
4751
4752TypedefDecl *ASTContext::getObjCSelDecl() const {
4753  if (!ObjCSelDecl) {
4754    QualType SelT = getPointerType(ObjCBuiltinSelTy);
4755    TypeSourceInfo *SelInfo = getTrivialTypeSourceInfo(SelT);
4756    ObjCSelDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4757                                      getTranslationUnitDecl(),
4758                                      SourceLocation(), SourceLocation(),
4759                                      &Idents.get("SEL"), SelInfo);
4760  }
4761  return ObjCSelDecl;
4762}
4763
4764void ASTContext::setObjCProtoType(QualType QT) {
4765  ObjCProtoType = QT;
4766}
4767
4768TypedefDecl *ASTContext::getObjCClassDecl() const {
4769  if (!ObjCClassDecl) {
4770    QualType T = getObjCObjectType(ObjCBuiltinClassTy, 0, 0);
4771    T = getObjCObjectPointerType(T);
4772    TypeSourceInfo *ClassInfo = getTrivialTypeSourceInfo(T);
4773    ObjCClassDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4774                                        getTranslationUnitDecl(),
4775                                        SourceLocation(), SourceLocation(),
4776                                        &Idents.get("Class"), ClassInfo);
4777  }
4778
4779  return ObjCClassDecl;
4780}
4781
4782void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4783  assert(ObjCConstantStringType.isNull() &&
4784         "'NSConstantString' type already set!");
4785
4786  ObjCConstantStringType = getObjCInterfaceType(Decl);
4787}
4788
4789/// \brief Retrieve the template name that corresponds to a non-empty
4790/// lookup.
4791TemplateName
4792ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4793                                      UnresolvedSetIterator End) const {
4794  unsigned size = End - Begin;
4795  assert(size > 1 && "set is not overloaded!");
4796
4797  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4798                          size * sizeof(FunctionTemplateDecl*));
4799  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4800
4801  NamedDecl **Storage = OT->getStorage();
4802  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4803    NamedDecl *D = *I;
4804    assert(isa<FunctionTemplateDecl>(D) ||
4805           (isa<UsingShadowDecl>(D) &&
4806            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4807    *Storage++ = D;
4808  }
4809
4810  return TemplateName(OT);
4811}
4812
4813/// \brief Retrieve the template name that represents a qualified
4814/// template name such as \c std::vector.
4815TemplateName
4816ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4817                                     bool TemplateKeyword,
4818                                     TemplateDecl *Template) const {
4819  assert(NNS && "Missing nested-name-specifier in qualified template name");
4820
4821  // FIXME: Canonicalization?
4822  llvm::FoldingSetNodeID ID;
4823  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4824
4825  void *InsertPos = 0;
4826  QualifiedTemplateName *QTN =
4827    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4828  if (!QTN) {
4829    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4830    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4831  }
4832
4833  return TemplateName(QTN);
4834}
4835
4836/// \brief Retrieve the template name that represents a dependent
4837/// template name such as \c MetaFun::template apply.
4838TemplateName
4839ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4840                                     const IdentifierInfo *Name) const {
4841  assert((!NNS || NNS->isDependent()) &&
4842         "Nested name specifier must be dependent");
4843
4844  llvm::FoldingSetNodeID ID;
4845  DependentTemplateName::Profile(ID, NNS, Name);
4846
4847  void *InsertPos = 0;
4848  DependentTemplateName *QTN =
4849    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4850
4851  if (QTN)
4852    return TemplateName(QTN);
4853
4854  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4855  if (CanonNNS == NNS) {
4856    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4857  } else {
4858    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4859    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4860    DependentTemplateName *CheckQTN =
4861      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4862    assert(!CheckQTN && "Dependent type name canonicalization broken");
4863    (void)CheckQTN;
4864  }
4865
4866  DependentTemplateNames.InsertNode(QTN, InsertPos);
4867  return TemplateName(QTN);
4868}
4869
4870/// \brief Retrieve the template name that represents a dependent
4871/// template name such as \c MetaFun::template operator+.
4872TemplateName
4873ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4874                                     OverloadedOperatorKind Operator) const {
4875  assert((!NNS || NNS->isDependent()) &&
4876         "Nested name specifier must be dependent");
4877
4878  llvm::FoldingSetNodeID ID;
4879  DependentTemplateName::Profile(ID, NNS, Operator);
4880
4881  void *InsertPos = 0;
4882  DependentTemplateName *QTN
4883    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4884
4885  if (QTN)
4886    return TemplateName(QTN);
4887
4888  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4889  if (CanonNNS == NNS) {
4890    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4891  } else {
4892    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4893    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4894
4895    DependentTemplateName *CheckQTN
4896      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4897    assert(!CheckQTN && "Dependent template name canonicalization broken");
4898    (void)CheckQTN;
4899  }
4900
4901  DependentTemplateNames.InsertNode(QTN, InsertPos);
4902  return TemplateName(QTN);
4903}
4904
4905TemplateName
4906ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
4907                                         TemplateName replacement) const {
4908  llvm::FoldingSetNodeID ID;
4909  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
4910
4911  void *insertPos = 0;
4912  SubstTemplateTemplateParmStorage *subst
4913    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
4914
4915  if (!subst) {
4916    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
4917    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
4918  }
4919
4920  return TemplateName(subst);
4921}
4922
4923TemplateName
4924ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
4925                                       const TemplateArgument &ArgPack) const {
4926  ASTContext &Self = const_cast<ASTContext &>(*this);
4927  llvm::FoldingSetNodeID ID;
4928  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
4929
4930  void *InsertPos = 0;
4931  SubstTemplateTemplateParmPackStorage *Subst
4932    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
4933
4934  if (!Subst) {
4935    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
4936                                                           ArgPack.pack_size(),
4937                                                         ArgPack.pack_begin());
4938    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
4939  }
4940
4941  return TemplateName(Subst);
4942}
4943
4944/// getFromTargetType - Given one of the integer types provided by
4945/// TargetInfo, produce the corresponding type. The unsigned @p Type
4946/// is actually a value of type @c TargetInfo::IntType.
4947CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4948  switch (Type) {
4949  case TargetInfo::NoInt: return CanQualType();
4950  case TargetInfo::SignedShort: return ShortTy;
4951  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4952  case TargetInfo::SignedInt: return IntTy;
4953  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4954  case TargetInfo::SignedLong: return LongTy;
4955  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4956  case TargetInfo::SignedLongLong: return LongLongTy;
4957  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4958  }
4959
4960  llvm_unreachable("Unhandled TargetInfo::IntType value");
4961}
4962
4963//===----------------------------------------------------------------------===//
4964//                        Type Predicates.
4965//===----------------------------------------------------------------------===//
4966
4967/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4968/// garbage collection attribute.
4969///
4970Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
4971  if (getLangOptions().getGC() == LangOptions::NonGC)
4972    return Qualifiers::GCNone;
4973
4974  assert(getLangOptions().ObjC1);
4975  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
4976
4977  // Default behaviour under objective-C's gc is for ObjC pointers
4978  // (or pointers to them) be treated as though they were declared
4979  // as __strong.
4980  if (GCAttrs == Qualifiers::GCNone) {
4981    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4982      return Qualifiers::Strong;
4983    else if (Ty->isPointerType())
4984      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4985  } else {
4986    // It's not valid to set GC attributes on anything that isn't a
4987    // pointer.
4988#ifndef NDEBUG
4989    QualType CT = Ty->getCanonicalTypeInternal();
4990    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
4991      CT = AT->getElementType();
4992    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
4993#endif
4994  }
4995  return GCAttrs;
4996}
4997
4998//===----------------------------------------------------------------------===//
4999//                        Type Compatibility Testing
5000//===----------------------------------------------------------------------===//
5001
5002/// areCompatVectorTypes - Return true if the two specified vector types are
5003/// compatible.
5004static bool areCompatVectorTypes(const VectorType *LHS,
5005                                 const VectorType *RHS) {
5006  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
5007  return LHS->getElementType() == RHS->getElementType() &&
5008         LHS->getNumElements() == RHS->getNumElements();
5009}
5010
5011bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
5012                                          QualType SecondVec) {
5013  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
5014  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
5015
5016  if (hasSameUnqualifiedType(FirstVec, SecondVec))
5017    return true;
5018
5019  // Treat Neon vector types and most AltiVec vector types as if they are the
5020  // equivalent GCC vector types.
5021  const VectorType *First = FirstVec->getAs<VectorType>();
5022  const VectorType *Second = SecondVec->getAs<VectorType>();
5023  if (First->getNumElements() == Second->getNumElements() &&
5024      hasSameType(First->getElementType(), Second->getElementType()) &&
5025      First->getVectorKind() != VectorType::AltiVecPixel &&
5026      First->getVectorKind() != VectorType::AltiVecBool &&
5027      Second->getVectorKind() != VectorType::AltiVecPixel &&
5028      Second->getVectorKind() != VectorType::AltiVecBool)
5029    return true;
5030
5031  return false;
5032}
5033
5034//===----------------------------------------------------------------------===//
5035// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
5036//===----------------------------------------------------------------------===//
5037
5038/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
5039/// inheritance hierarchy of 'rProto'.
5040bool
5041ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
5042                                           ObjCProtocolDecl *rProto) const {
5043  if (lProto == rProto)
5044    return true;
5045  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
5046       E = rProto->protocol_end(); PI != E; ++PI)
5047    if (ProtocolCompatibleWithProtocol(lProto, *PI))
5048      return true;
5049  return false;
5050}
5051
5052/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
5053/// return true if lhs's protocols conform to rhs's protocol; false
5054/// otherwise.
5055bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
5056  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
5057    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
5058  return false;
5059}
5060
5061/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
5062/// Class<p1, ...>.
5063bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
5064                                                      QualType rhs) {
5065  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
5066  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5067  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
5068
5069  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5070       E = lhsQID->qual_end(); I != E; ++I) {
5071    bool match = false;
5072    ObjCProtocolDecl *lhsProto = *I;
5073    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5074         E = rhsOPT->qual_end(); J != E; ++J) {
5075      ObjCProtocolDecl *rhsProto = *J;
5076      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
5077        match = true;
5078        break;
5079      }
5080    }
5081    if (!match)
5082      return false;
5083  }
5084  return true;
5085}
5086
5087/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
5088/// ObjCQualifiedIDType.
5089bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
5090                                                   bool compare) {
5091  // Allow id<P..> and an 'id' or void* type in all cases.
5092  if (lhs->isVoidPointerType() ||
5093      lhs->isObjCIdType() || lhs->isObjCClassType())
5094    return true;
5095  else if (rhs->isVoidPointerType() ||
5096           rhs->isObjCIdType() || rhs->isObjCClassType())
5097    return true;
5098
5099  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
5100    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5101
5102    if (!rhsOPT) return false;
5103
5104    if (rhsOPT->qual_empty()) {
5105      // If the RHS is a unqualified interface pointer "NSString*",
5106      // make sure we check the class hierarchy.
5107      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5108        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5109             E = lhsQID->qual_end(); I != E; ++I) {
5110          // when comparing an id<P> on lhs with a static type on rhs,
5111          // see if static class implements all of id's protocols, directly or
5112          // through its super class and categories.
5113          if (!rhsID->ClassImplementsProtocol(*I, true))
5114            return false;
5115        }
5116      }
5117      // If there are no qualifiers and no interface, we have an 'id'.
5118      return true;
5119    }
5120    // Both the right and left sides have qualifiers.
5121    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5122         E = lhsQID->qual_end(); I != E; ++I) {
5123      ObjCProtocolDecl *lhsProto = *I;
5124      bool match = false;
5125
5126      // when comparing an id<P> on lhs with a static type on rhs,
5127      // see if static class implements all of id's protocols, directly or
5128      // through its super class and categories.
5129      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5130           E = rhsOPT->qual_end(); J != E; ++J) {
5131        ObjCProtocolDecl *rhsProto = *J;
5132        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5133            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5134          match = true;
5135          break;
5136        }
5137      }
5138      // If the RHS is a qualified interface pointer "NSString<P>*",
5139      // make sure we check the class hierarchy.
5140      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5141        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5142             E = lhsQID->qual_end(); I != E; ++I) {
5143          // when comparing an id<P> on lhs with a static type on rhs,
5144          // see if static class implements all of id's protocols, directly or
5145          // through its super class and categories.
5146          if (rhsID->ClassImplementsProtocol(*I, true)) {
5147            match = true;
5148            break;
5149          }
5150        }
5151      }
5152      if (!match)
5153        return false;
5154    }
5155
5156    return true;
5157  }
5158
5159  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
5160  assert(rhsQID && "One of the LHS/RHS should be id<x>");
5161
5162  if (const ObjCObjectPointerType *lhsOPT =
5163        lhs->getAsObjCInterfacePointerType()) {
5164    // If both the right and left sides have qualifiers.
5165    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
5166         E = lhsOPT->qual_end(); I != E; ++I) {
5167      ObjCProtocolDecl *lhsProto = *I;
5168      bool match = false;
5169
5170      // when comparing an id<P> on rhs with a static type on lhs,
5171      // see if static class implements all of id's protocols, directly or
5172      // through its super class and categories.
5173      // First, lhs protocols in the qualifier list must be found, direct
5174      // or indirect in rhs's qualifier list or it is a mismatch.
5175      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5176           E = rhsQID->qual_end(); J != E; ++J) {
5177        ObjCProtocolDecl *rhsProto = *J;
5178        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5179            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5180          match = true;
5181          break;
5182        }
5183      }
5184      if (!match)
5185        return false;
5186    }
5187
5188    // Static class's protocols, or its super class or category protocols
5189    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
5190    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
5191      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5192      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
5193      // This is rather dubious but matches gcc's behavior. If lhs has
5194      // no type qualifier and its class has no static protocol(s)
5195      // assume that it is mismatch.
5196      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
5197        return false;
5198      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5199           LHSInheritedProtocols.begin(),
5200           E = LHSInheritedProtocols.end(); I != E; ++I) {
5201        bool match = false;
5202        ObjCProtocolDecl *lhsProto = (*I);
5203        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5204             E = rhsQID->qual_end(); J != E; ++J) {
5205          ObjCProtocolDecl *rhsProto = *J;
5206          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5207              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5208            match = true;
5209            break;
5210          }
5211        }
5212        if (!match)
5213          return false;
5214      }
5215    }
5216    return true;
5217  }
5218  return false;
5219}
5220
5221/// canAssignObjCInterfaces - Return true if the two interface types are
5222/// compatible for assignment from RHS to LHS.  This handles validation of any
5223/// protocol qualifiers on the LHS or RHS.
5224///
5225bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
5226                                         const ObjCObjectPointerType *RHSOPT) {
5227  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5228  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5229
5230  // If either type represents the built-in 'id' or 'Class' types, return true.
5231  if (LHS->isObjCUnqualifiedIdOrClass() ||
5232      RHS->isObjCUnqualifiedIdOrClass())
5233    return true;
5234
5235  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
5236    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5237                                             QualType(RHSOPT,0),
5238                                             false);
5239
5240  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
5241    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
5242                                                QualType(RHSOPT,0));
5243
5244  // If we have 2 user-defined types, fall into that path.
5245  if (LHS->getInterface() && RHS->getInterface())
5246    return canAssignObjCInterfaces(LHS, RHS);
5247
5248  return false;
5249}
5250
5251/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
5252/// for providing type-safety for objective-c pointers used to pass/return
5253/// arguments in block literals. When passed as arguments, passing 'A*' where
5254/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
5255/// not OK. For the return type, the opposite is not OK.
5256bool ASTContext::canAssignObjCInterfacesInBlockPointer(
5257                                         const ObjCObjectPointerType *LHSOPT,
5258                                         const ObjCObjectPointerType *RHSOPT,
5259                                         bool BlockReturnType) {
5260  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
5261    return true;
5262
5263  if (LHSOPT->isObjCBuiltinType()) {
5264    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
5265  }
5266
5267  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
5268    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5269                                             QualType(RHSOPT,0),
5270                                             false);
5271
5272  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
5273  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
5274  if (LHS && RHS)  { // We have 2 user-defined types.
5275    if (LHS != RHS) {
5276      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
5277        return BlockReturnType;
5278      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
5279        return !BlockReturnType;
5280    }
5281    else
5282      return true;
5283  }
5284  return false;
5285}
5286
5287/// getIntersectionOfProtocols - This routine finds the intersection of set
5288/// of protocols inherited from two distinct objective-c pointer objects.
5289/// It is used to build composite qualifier list of the composite type of
5290/// the conditional expression involving two objective-c pointer objects.
5291static
5292void getIntersectionOfProtocols(ASTContext &Context,
5293                                const ObjCObjectPointerType *LHSOPT,
5294                                const ObjCObjectPointerType *RHSOPT,
5295      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
5296
5297  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5298  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5299  assert(LHS->getInterface() && "LHS must have an interface base");
5300  assert(RHS->getInterface() && "RHS must have an interface base");
5301
5302  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
5303  unsigned LHSNumProtocols = LHS->getNumProtocols();
5304  if (LHSNumProtocols > 0)
5305    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
5306  else {
5307    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5308    Context.CollectInheritedProtocols(LHS->getInterface(),
5309                                      LHSInheritedProtocols);
5310    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
5311                                LHSInheritedProtocols.end());
5312  }
5313
5314  unsigned RHSNumProtocols = RHS->getNumProtocols();
5315  if (RHSNumProtocols > 0) {
5316    ObjCProtocolDecl **RHSProtocols =
5317      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
5318    for (unsigned i = 0; i < RHSNumProtocols; ++i)
5319      if (InheritedProtocolSet.count(RHSProtocols[i]))
5320        IntersectionOfProtocols.push_back(RHSProtocols[i]);
5321  } else {
5322    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
5323    Context.CollectInheritedProtocols(RHS->getInterface(),
5324                                      RHSInheritedProtocols);
5325    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5326         RHSInheritedProtocols.begin(),
5327         E = RHSInheritedProtocols.end(); I != E; ++I)
5328      if (InheritedProtocolSet.count((*I)))
5329        IntersectionOfProtocols.push_back((*I));
5330  }
5331}
5332
5333/// areCommonBaseCompatible - Returns common base class of the two classes if
5334/// one found. Note that this is O'2 algorithm. But it will be called as the
5335/// last type comparison in a ?-exp of ObjC pointer types before a
5336/// warning is issued. So, its invokation is extremely rare.
5337QualType ASTContext::areCommonBaseCompatible(
5338                                          const ObjCObjectPointerType *Lptr,
5339                                          const ObjCObjectPointerType *Rptr) {
5340  const ObjCObjectType *LHS = Lptr->getObjectType();
5341  const ObjCObjectType *RHS = Rptr->getObjectType();
5342  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
5343  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
5344  if (!LDecl || !RDecl || (LDecl == RDecl))
5345    return QualType();
5346
5347  do {
5348    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
5349    if (canAssignObjCInterfaces(LHS, RHS)) {
5350      SmallVector<ObjCProtocolDecl *, 8> Protocols;
5351      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
5352
5353      QualType Result = QualType(LHS, 0);
5354      if (!Protocols.empty())
5355        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
5356      Result = getObjCObjectPointerType(Result);
5357      return Result;
5358    }
5359  } while ((LDecl = LDecl->getSuperClass()));
5360
5361  return QualType();
5362}
5363
5364bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
5365                                         const ObjCObjectType *RHS) {
5366  assert(LHS->getInterface() && "LHS is not an interface type");
5367  assert(RHS->getInterface() && "RHS is not an interface type");
5368
5369  // Verify that the base decls are compatible: the RHS must be a subclass of
5370  // the LHS.
5371  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
5372    return false;
5373
5374  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
5375  // protocol qualified at all, then we are good.
5376  if (LHS->getNumProtocols() == 0)
5377    return true;
5378
5379  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't,
5380  // more detailed analysis is required.
5381  if (RHS->getNumProtocols() == 0) {
5382    // OK, if LHS is a superclass of RHS *and*
5383    // this superclass is assignment compatible with LHS.
5384    // false otherwise.
5385    bool IsSuperClass =
5386      LHS->getInterface()->isSuperClassOf(RHS->getInterface());
5387    if (IsSuperClass) {
5388      // OK if conversion of LHS to SuperClass results in narrowing of types
5389      // ; i.e., SuperClass may implement at least one of the protocols
5390      // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
5391      // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
5392      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
5393      CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
5394      // If super class has no protocols, it is not a match.
5395      if (SuperClassInheritedProtocols.empty())
5396        return false;
5397
5398      for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5399           LHSPE = LHS->qual_end();
5400           LHSPI != LHSPE; LHSPI++) {
5401        bool SuperImplementsProtocol = false;
5402        ObjCProtocolDecl *LHSProto = (*LHSPI);
5403
5404        for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5405             SuperClassInheritedProtocols.begin(),
5406             E = SuperClassInheritedProtocols.end(); I != E; ++I) {
5407          ObjCProtocolDecl *SuperClassProto = (*I);
5408          if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
5409            SuperImplementsProtocol = true;
5410            break;
5411          }
5412        }
5413        if (!SuperImplementsProtocol)
5414          return false;
5415      }
5416      return true;
5417    }
5418    return false;
5419  }
5420
5421  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5422                                     LHSPE = LHS->qual_end();
5423       LHSPI != LHSPE; LHSPI++) {
5424    bool RHSImplementsProtocol = false;
5425
5426    // If the RHS doesn't implement the protocol on the left, the types
5427    // are incompatible.
5428    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
5429                                       RHSPE = RHS->qual_end();
5430         RHSPI != RHSPE; RHSPI++) {
5431      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
5432        RHSImplementsProtocol = true;
5433        break;
5434      }
5435    }
5436    // FIXME: For better diagnostics, consider passing back the protocol name.
5437    if (!RHSImplementsProtocol)
5438      return false;
5439  }
5440  // The RHS implements all protocols listed on the LHS.
5441  return true;
5442}
5443
5444bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
5445  // get the "pointed to" types
5446  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
5447  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
5448
5449  if (!LHSOPT || !RHSOPT)
5450    return false;
5451
5452  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
5453         canAssignObjCInterfaces(RHSOPT, LHSOPT);
5454}
5455
5456bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
5457  return canAssignObjCInterfaces(
5458                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
5459                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
5460}
5461
5462/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
5463/// both shall have the identically qualified version of a compatible type.
5464/// C99 6.2.7p1: Two types have compatible types if their types are the
5465/// same. See 6.7.[2,3,5] for additional rules.
5466bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
5467                                    bool CompareUnqualified) {
5468  if (getLangOptions().CPlusPlus)
5469    return hasSameType(LHS, RHS);
5470
5471  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
5472}
5473
5474bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
5475  return typesAreCompatible(LHS, RHS);
5476}
5477
5478bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
5479  return !mergeTypes(LHS, RHS, true).isNull();
5480}
5481
5482/// mergeTransparentUnionType - if T is a transparent union type and a member
5483/// of T is compatible with SubType, return the merged type, else return
5484/// QualType()
5485QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
5486                                               bool OfBlockPointer,
5487                                               bool Unqualified) {
5488  if (const RecordType *UT = T->getAsUnionType()) {
5489    RecordDecl *UD = UT->getDecl();
5490    if (UD->hasAttr<TransparentUnionAttr>()) {
5491      for (RecordDecl::field_iterator it = UD->field_begin(),
5492           itend = UD->field_end(); it != itend; ++it) {
5493        QualType ET = it->getType().getUnqualifiedType();
5494        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
5495        if (!MT.isNull())
5496          return MT;
5497      }
5498    }
5499  }
5500
5501  return QualType();
5502}
5503
5504/// mergeFunctionArgumentTypes - merge two types which appear as function
5505/// argument types
5506QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
5507                                                bool OfBlockPointer,
5508                                                bool Unqualified) {
5509  // GNU extension: two types are compatible if they appear as a function
5510  // argument, one of the types is a transparent union type and the other
5511  // type is compatible with a union member
5512  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
5513                                              Unqualified);
5514  if (!lmerge.isNull())
5515    return lmerge;
5516
5517  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
5518                                              Unqualified);
5519  if (!rmerge.isNull())
5520    return rmerge;
5521
5522  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
5523}
5524
5525QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
5526                                        bool OfBlockPointer,
5527                                        bool Unqualified) {
5528  const FunctionType *lbase = lhs->getAs<FunctionType>();
5529  const FunctionType *rbase = rhs->getAs<FunctionType>();
5530  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
5531  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
5532  bool allLTypes = true;
5533  bool allRTypes = true;
5534
5535  // Check return type
5536  QualType retType;
5537  if (OfBlockPointer) {
5538    QualType RHS = rbase->getResultType();
5539    QualType LHS = lbase->getResultType();
5540    bool UnqualifiedResult = Unqualified;
5541    if (!UnqualifiedResult)
5542      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
5543    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
5544  }
5545  else
5546    retType = mergeTypes(lbase->getResultType(), rbase->getResultType(), false,
5547                         Unqualified);
5548  if (retType.isNull()) return QualType();
5549
5550  if (Unqualified)
5551    retType = retType.getUnqualifiedType();
5552
5553  CanQualType LRetType = getCanonicalType(lbase->getResultType());
5554  CanQualType RRetType = getCanonicalType(rbase->getResultType());
5555  if (Unqualified) {
5556    LRetType = LRetType.getUnqualifiedType();
5557    RRetType = RRetType.getUnqualifiedType();
5558  }
5559
5560  if (getCanonicalType(retType) != LRetType)
5561    allLTypes = false;
5562  if (getCanonicalType(retType) != RRetType)
5563    allRTypes = false;
5564
5565  // FIXME: double check this
5566  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
5567  //                           rbase->getRegParmAttr() != 0 &&
5568  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
5569  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
5570  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
5571
5572  // Compatible functions must have compatible calling conventions
5573  if (!isSameCallConv(lbaseInfo.getCC(), rbaseInfo.getCC()))
5574    return QualType();
5575
5576  // Regparm is part of the calling convention.
5577  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
5578    return QualType();
5579  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
5580    return QualType();
5581
5582  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
5583    return QualType();
5584
5585  // functypes which return are preferred over those that do not.
5586  if (lbaseInfo.getNoReturn() && !rbaseInfo.getNoReturn())
5587    allLTypes = false;
5588  else if (!lbaseInfo.getNoReturn() && rbaseInfo.getNoReturn())
5589    allRTypes = false;
5590  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
5591  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
5592
5593  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
5594
5595  if (lproto && rproto) { // two C99 style function prototypes
5596    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
5597           "C++ shouldn't be here");
5598    unsigned lproto_nargs = lproto->getNumArgs();
5599    unsigned rproto_nargs = rproto->getNumArgs();
5600
5601    // Compatible functions must have the same number of arguments
5602    if (lproto_nargs != rproto_nargs)
5603      return QualType();
5604
5605    // Variadic and non-variadic functions aren't compatible
5606    if (lproto->isVariadic() != rproto->isVariadic())
5607      return QualType();
5608
5609    if (lproto->getTypeQuals() != rproto->getTypeQuals())
5610      return QualType();
5611
5612    if (LangOpts.ObjCAutoRefCount &&
5613        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
5614      return QualType();
5615
5616    // Check argument compatibility
5617    SmallVector<QualType, 10> types;
5618    for (unsigned i = 0; i < lproto_nargs; i++) {
5619      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
5620      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
5621      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
5622                                                    OfBlockPointer,
5623                                                    Unqualified);
5624      if (argtype.isNull()) return QualType();
5625
5626      if (Unqualified)
5627        argtype = argtype.getUnqualifiedType();
5628
5629      types.push_back(argtype);
5630      if (Unqualified) {
5631        largtype = largtype.getUnqualifiedType();
5632        rargtype = rargtype.getUnqualifiedType();
5633      }
5634
5635      if (getCanonicalType(argtype) != getCanonicalType(largtype))
5636        allLTypes = false;
5637      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
5638        allRTypes = false;
5639    }
5640
5641    if (allLTypes) return lhs;
5642    if (allRTypes) return rhs;
5643
5644    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
5645    EPI.ExtInfo = einfo;
5646    return getFunctionType(retType, types.begin(), types.size(), EPI);
5647  }
5648
5649  if (lproto) allRTypes = false;
5650  if (rproto) allLTypes = false;
5651
5652  const FunctionProtoType *proto = lproto ? lproto : rproto;
5653  if (proto) {
5654    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
5655    if (proto->isVariadic()) return QualType();
5656    // Check that the types are compatible with the types that
5657    // would result from default argument promotions (C99 6.7.5.3p15).
5658    // The only types actually affected are promotable integer
5659    // types and floats, which would be passed as a different
5660    // type depending on whether the prototype is visible.
5661    unsigned proto_nargs = proto->getNumArgs();
5662    for (unsigned i = 0; i < proto_nargs; ++i) {
5663      QualType argTy = proto->getArgType(i);
5664
5665      // Look at the promotion type of enum types, since that is the type used
5666      // to pass enum values.
5667      if (const EnumType *Enum = argTy->getAs<EnumType>())
5668        argTy = Enum->getDecl()->getPromotionType();
5669
5670      if (argTy->isPromotableIntegerType() ||
5671          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
5672        return QualType();
5673    }
5674
5675    if (allLTypes) return lhs;
5676    if (allRTypes) return rhs;
5677
5678    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
5679    EPI.ExtInfo = einfo;
5680    return getFunctionType(retType, proto->arg_type_begin(),
5681                           proto->getNumArgs(), EPI);
5682  }
5683
5684  if (allLTypes) return lhs;
5685  if (allRTypes) return rhs;
5686  return getFunctionNoProtoType(retType, einfo);
5687}
5688
5689QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
5690                                bool OfBlockPointer,
5691                                bool Unqualified, bool BlockReturnType) {
5692  // C++ [expr]: If an expression initially has the type "reference to T", the
5693  // type is adjusted to "T" prior to any further analysis, the expression
5694  // designates the object or function denoted by the reference, and the
5695  // expression is an lvalue unless the reference is an rvalue reference and
5696  // the expression is a function call (possibly inside parentheses).
5697  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
5698  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
5699
5700  if (Unqualified) {
5701    LHS = LHS.getUnqualifiedType();
5702    RHS = RHS.getUnqualifiedType();
5703  }
5704
5705  QualType LHSCan = getCanonicalType(LHS),
5706           RHSCan = getCanonicalType(RHS);
5707
5708  // If two types are identical, they are compatible.
5709  if (LHSCan == RHSCan)
5710    return LHS;
5711
5712  // If the qualifiers are different, the types aren't compatible... mostly.
5713  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5714  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5715  if (LQuals != RQuals) {
5716    // If any of these qualifiers are different, we have a type
5717    // mismatch.
5718    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5719        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
5720        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
5721      return QualType();
5722
5723    // Exactly one GC qualifier difference is allowed: __strong is
5724    // okay if the other type has no GC qualifier but is an Objective
5725    // C object pointer (i.e. implicitly strong by default).  We fix
5726    // this by pretending that the unqualified type was actually
5727    // qualified __strong.
5728    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5729    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5730    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5731
5732    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5733      return QualType();
5734
5735    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
5736      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
5737    }
5738    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
5739      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
5740    }
5741    return QualType();
5742  }
5743
5744  // Okay, qualifiers are equal.
5745
5746  Type::TypeClass LHSClass = LHSCan->getTypeClass();
5747  Type::TypeClass RHSClass = RHSCan->getTypeClass();
5748
5749  // We want to consider the two function types to be the same for these
5750  // comparisons, just force one to the other.
5751  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
5752  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
5753
5754  // Same as above for arrays
5755  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
5756    LHSClass = Type::ConstantArray;
5757  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
5758    RHSClass = Type::ConstantArray;
5759
5760  // ObjCInterfaces are just specialized ObjCObjects.
5761  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
5762  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
5763
5764  // Canonicalize ExtVector -> Vector.
5765  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
5766  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
5767
5768  // If the canonical type classes don't match.
5769  if (LHSClass != RHSClass) {
5770    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
5771    // a signed integer type, or an unsigned integer type.
5772    // Compatibility is based on the underlying type, not the promotion
5773    // type.
5774    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
5775      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
5776        return RHS;
5777    }
5778    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
5779      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
5780        return LHS;
5781    }
5782
5783    return QualType();
5784  }
5785
5786  // The canonical type classes match.
5787  switch (LHSClass) {
5788#define TYPE(Class, Base)
5789#define ABSTRACT_TYPE(Class, Base)
5790#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
5791#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
5792#define DEPENDENT_TYPE(Class, Base) case Type::Class:
5793#include "clang/AST/TypeNodes.def"
5794    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
5795
5796  case Type::LValueReference:
5797  case Type::RValueReference:
5798  case Type::MemberPointer:
5799    llvm_unreachable("C++ should never be in mergeTypes");
5800
5801  case Type::ObjCInterface:
5802  case Type::IncompleteArray:
5803  case Type::VariableArray:
5804  case Type::FunctionProto:
5805  case Type::ExtVector:
5806    llvm_unreachable("Types are eliminated above");
5807
5808  case Type::Pointer:
5809  {
5810    // Merge two pointer types, while trying to preserve typedef info
5811    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
5812    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
5813    if (Unqualified) {
5814      LHSPointee = LHSPointee.getUnqualifiedType();
5815      RHSPointee = RHSPointee.getUnqualifiedType();
5816    }
5817    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
5818                                     Unqualified);
5819    if (ResultType.isNull()) return QualType();
5820    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5821      return LHS;
5822    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5823      return RHS;
5824    return getPointerType(ResultType);
5825  }
5826  case Type::BlockPointer:
5827  {
5828    // Merge two block pointer types, while trying to preserve typedef info
5829    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
5830    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
5831    if (Unqualified) {
5832      LHSPointee = LHSPointee.getUnqualifiedType();
5833      RHSPointee = RHSPointee.getUnqualifiedType();
5834    }
5835    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
5836                                     Unqualified);
5837    if (ResultType.isNull()) return QualType();
5838    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5839      return LHS;
5840    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5841      return RHS;
5842    return getBlockPointerType(ResultType);
5843  }
5844  case Type::Atomic:
5845  {
5846    // Merge two pointer types, while trying to preserve typedef info
5847    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
5848    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
5849    if (Unqualified) {
5850      LHSValue = LHSValue.getUnqualifiedType();
5851      RHSValue = RHSValue.getUnqualifiedType();
5852    }
5853    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
5854                                     Unqualified);
5855    if (ResultType.isNull()) return QualType();
5856    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
5857      return LHS;
5858    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
5859      return RHS;
5860    return getAtomicType(ResultType);
5861  }
5862  case Type::ConstantArray:
5863  {
5864    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
5865    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
5866    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
5867      return QualType();
5868
5869    QualType LHSElem = getAsArrayType(LHS)->getElementType();
5870    QualType RHSElem = getAsArrayType(RHS)->getElementType();
5871    if (Unqualified) {
5872      LHSElem = LHSElem.getUnqualifiedType();
5873      RHSElem = RHSElem.getUnqualifiedType();
5874    }
5875
5876    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
5877    if (ResultType.isNull()) return QualType();
5878    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5879      return LHS;
5880    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5881      return RHS;
5882    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
5883                                          ArrayType::ArraySizeModifier(), 0);
5884    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
5885                                          ArrayType::ArraySizeModifier(), 0);
5886    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
5887    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
5888    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5889      return LHS;
5890    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5891      return RHS;
5892    if (LVAT) {
5893      // FIXME: This isn't correct! But tricky to implement because
5894      // the array's size has to be the size of LHS, but the type
5895      // has to be different.
5896      return LHS;
5897    }
5898    if (RVAT) {
5899      // FIXME: This isn't correct! But tricky to implement because
5900      // the array's size has to be the size of RHS, but the type
5901      // has to be different.
5902      return RHS;
5903    }
5904    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
5905    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
5906    return getIncompleteArrayType(ResultType,
5907                                  ArrayType::ArraySizeModifier(), 0);
5908  }
5909  case Type::FunctionNoProto:
5910    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
5911  case Type::Record:
5912  case Type::Enum:
5913    return QualType();
5914  case Type::Builtin:
5915    // Only exactly equal builtin types are compatible, which is tested above.
5916    return QualType();
5917  case Type::Complex:
5918    // Distinct complex types are incompatible.
5919    return QualType();
5920  case Type::Vector:
5921    // FIXME: The merged type should be an ExtVector!
5922    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
5923                             RHSCan->getAs<VectorType>()))
5924      return LHS;
5925    return QualType();
5926  case Type::ObjCObject: {
5927    // Check if the types are assignment compatible.
5928    // FIXME: This should be type compatibility, e.g. whether
5929    // "LHS x; RHS x;" at global scope is legal.
5930    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
5931    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
5932    if (canAssignObjCInterfaces(LHSIface, RHSIface))
5933      return LHS;
5934
5935    return QualType();
5936  }
5937  case Type::ObjCObjectPointer: {
5938    if (OfBlockPointer) {
5939      if (canAssignObjCInterfacesInBlockPointer(
5940                                          LHS->getAs<ObjCObjectPointerType>(),
5941                                          RHS->getAs<ObjCObjectPointerType>(),
5942                                          BlockReturnType))
5943      return LHS;
5944      return QualType();
5945    }
5946    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
5947                                RHS->getAs<ObjCObjectPointerType>()))
5948      return LHS;
5949
5950    return QualType();
5951    }
5952  }
5953
5954  return QualType();
5955}
5956
5957bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
5958                   const FunctionProtoType *FromFunctionType,
5959                   const FunctionProtoType *ToFunctionType) {
5960  if (FromFunctionType->hasAnyConsumedArgs() !=
5961      ToFunctionType->hasAnyConsumedArgs())
5962    return false;
5963  FunctionProtoType::ExtProtoInfo FromEPI =
5964    FromFunctionType->getExtProtoInfo();
5965  FunctionProtoType::ExtProtoInfo ToEPI =
5966    ToFunctionType->getExtProtoInfo();
5967  if (FromEPI.ConsumedArguments && ToEPI.ConsumedArguments)
5968    for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs();
5969         ArgIdx != NumArgs; ++ArgIdx)  {
5970      if (FromEPI.ConsumedArguments[ArgIdx] !=
5971          ToEPI.ConsumedArguments[ArgIdx])
5972        return false;
5973    }
5974  return true;
5975}
5976
5977/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
5978/// 'RHS' attributes and returns the merged version; including for function
5979/// return types.
5980QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
5981  QualType LHSCan = getCanonicalType(LHS),
5982  RHSCan = getCanonicalType(RHS);
5983  // If two types are identical, they are compatible.
5984  if (LHSCan == RHSCan)
5985    return LHS;
5986  if (RHSCan->isFunctionType()) {
5987    if (!LHSCan->isFunctionType())
5988      return QualType();
5989    QualType OldReturnType =
5990      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
5991    QualType NewReturnType =
5992      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
5993    QualType ResReturnType =
5994      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
5995    if (ResReturnType.isNull())
5996      return QualType();
5997    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
5998      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
5999      // In either case, use OldReturnType to build the new function type.
6000      const FunctionType *F = LHS->getAs<FunctionType>();
6001      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
6002        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
6003        EPI.ExtInfo = getFunctionExtInfo(LHS);
6004        QualType ResultType
6005          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
6006                            FPT->getNumArgs(), EPI);
6007        return ResultType;
6008      }
6009    }
6010    return QualType();
6011  }
6012
6013  // If the qualifiers are different, the types can still be merged.
6014  Qualifiers LQuals = LHSCan.getLocalQualifiers();
6015  Qualifiers RQuals = RHSCan.getLocalQualifiers();
6016  if (LQuals != RQuals) {
6017    // If any of these qualifiers are different, we have a type mismatch.
6018    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
6019        LQuals.getAddressSpace() != RQuals.getAddressSpace())
6020      return QualType();
6021
6022    // Exactly one GC qualifier difference is allowed: __strong is
6023    // okay if the other type has no GC qualifier but is an Objective
6024    // C object pointer (i.e. implicitly strong by default).  We fix
6025    // this by pretending that the unqualified type was actually
6026    // qualified __strong.
6027    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
6028    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
6029    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
6030
6031    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
6032      return QualType();
6033
6034    if (GC_L == Qualifiers::Strong)
6035      return LHS;
6036    if (GC_R == Qualifiers::Strong)
6037      return RHS;
6038    return QualType();
6039  }
6040
6041  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
6042    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6043    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6044    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
6045    if (ResQT == LHSBaseQT)
6046      return LHS;
6047    if (ResQT == RHSBaseQT)
6048      return RHS;
6049  }
6050  return QualType();
6051}
6052
6053//===----------------------------------------------------------------------===//
6054//                         Integer Predicates
6055//===----------------------------------------------------------------------===//
6056
6057unsigned ASTContext::getIntWidth(QualType T) const {
6058  if (const EnumType *ET = dyn_cast<EnumType>(T))
6059    T = ET->getDecl()->getIntegerType();
6060  if (T->isBooleanType())
6061    return 1;
6062  // For builtin types, just use the standard type sizing method
6063  return (unsigned)getTypeSize(T);
6064}
6065
6066QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
6067  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
6068
6069  // Turn <4 x signed int> -> <4 x unsigned int>
6070  if (const VectorType *VTy = T->getAs<VectorType>())
6071    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
6072                         VTy->getNumElements(), VTy->getVectorKind());
6073
6074  // For enums, we return the unsigned version of the base type.
6075  if (const EnumType *ETy = T->getAs<EnumType>())
6076    T = ETy->getDecl()->getIntegerType();
6077
6078  const BuiltinType *BTy = T->getAs<BuiltinType>();
6079  assert(BTy && "Unexpected signed integer type");
6080  switch (BTy->getKind()) {
6081  case BuiltinType::Char_S:
6082  case BuiltinType::SChar:
6083    return UnsignedCharTy;
6084  case BuiltinType::Short:
6085    return UnsignedShortTy;
6086  case BuiltinType::Int:
6087    return UnsignedIntTy;
6088  case BuiltinType::Long:
6089    return UnsignedLongTy;
6090  case BuiltinType::LongLong:
6091    return UnsignedLongLongTy;
6092  case BuiltinType::Int128:
6093    return UnsignedInt128Ty;
6094  default:
6095    llvm_unreachable("Unexpected signed integer type");
6096  }
6097}
6098
6099ASTMutationListener::~ASTMutationListener() { }
6100
6101
6102//===----------------------------------------------------------------------===//
6103//                          Builtin Type Computation
6104//===----------------------------------------------------------------------===//
6105
6106/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
6107/// pointer over the consumed characters.  This returns the resultant type.  If
6108/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
6109/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
6110/// a vector of "i*".
6111///
6112/// RequiresICE is filled in on return to indicate whether the value is required
6113/// to be an Integer Constant Expression.
6114static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
6115                                  ASTContext::GetBuiltinTypeError &Error,
6116                                  bool &RequiresICE,
6117                                  bool AllowTypeModifiers) {
6118  // Modifiers.
6119  int HowLong = 0;
6120  bool Signed = false, Unsigned = false;
6121  RequiresICE = false;
6122
6123  // Read the prefixed modifiers first.
6124  bool Done = false;
6125  while (!Done) {
6126    switch (*Str++) {
6127    default: Done = true; --Str; break;
6128    case 'I':
6129      RequiresICE = true;
6130      break;
6131    case 'S':
6132      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
6133      assert(!Signed && "Can't use 'S' modifier multiple times!");
6134      Signed = true;
6135      break;
6136    case 'U':
6137      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
6138      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
6139      Unsigned = true;
6140      break;
6141    case 'L':
6142      assert(HowLong <= 2 && "Can't have LLLL modifier");
6143      ++HowLong;
6144      break;
6145    }
6146  }
6147
6148  QualType Type;
6149
6150  // Read the base type.
6151  switch (*Str++) {
6152  default: llvm_unreachable("Unknown builtin type letter!");
6153  case 'v':
6154    assert(HowLong == 0 && !Signed && !Unsigned &&
6155           "Bad modifiers used with 'v'!");
6156    Type = Context.VoidTy;
6157    break;
6158  case 'f':
6159    assert(HowLong == 0 && !Signed && !Unsigned &&
6160           "Bad modifiers used with 'f'!");
6161    Type = Context.FloatTy;
6162    break;
6163  case 'd':
6164    assert(HowLong < 2 && !Signed && !Unsigned &&
6165           "Bad modifiers used with 'd'!");
6166    if (HowLong)
6167      Type = Context.LongDoubleTy;
6168    else
6169      Type = Context.DoubleTy;
6170    break;
6171  case 's':
6172    assert(HowLong == 0 && "Bad modifiers used with 's'!");
6173    if (Unsigned)
6174      Type = Context.UnsignedShortTy;
6175    else
6176      Type = Context.ShortTy;
6177    break;
6178  case 'i':
6179    if (HowLong == 3)
6180      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
6181    else if (HowLong == 2)
6182      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
6183    else if (HowLong == 1)
6184      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
6185    else
6186      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
6187    break;
6188  case 'c':
6189    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
6190    if (Signed)
6191      Type = Context.SignedCharTy;
6192    else if (Unsigned)
6193      Type = Context.UnsignedCharTy;
6194    else
6195      Type = Context.CharTy;
6196    break;
6197  case 'b': // boolean
6198    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
6199    Type = Context.BoolTy;
6200    break;
6201  case 'z':  // size_t.
6202    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
6203    Type = Context.getSizeType();
6204    break;
6205  case 'F':
6206    Type = Context.getCFConstantStringType();
6207    break;
6208  case 'G':
6209    Type = Context.getObjCIdType();
6210    break;
6211  case 'H':
6212    Type = Context.getObjCSelType();
6213    break;
6214  case 'a':
6215    Type = Context.getBuiltinVaListType();
6216    assert(!Type.isNull() && "builtin va list type not initialized!");
6217    break;
6218  case 'A':
6219    // This is a "reference" to a va_list; however, what exactly
6220    // this means depends on how va_list is defined. There are two
6221    // different kinds of va_list: ones passed by value, and ones
6222    // passed by reference.  An example of a by-value va_list is
6223    // x86, where va_list is a char*. An example of by-ref va_list
6224    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
6225    // we want this argument to be a char*&; for x86-64, we want
6226    // it to be a __va_list_tag*.
6227    Type = Context.getBuiltinVaListType();
6228    assert(!Type.isNull() && "builtin va list type not initialized!");
6229    if (Type->isArrayType())
6230      Type = Context.getArrayDecayedType(Type);
6231    else
6232      Type = Context.getLValueReferenceType(Type);
6233    break;
6234  case 'V': {
6235    char *End;
6236    unsigned NumElements = strtoul(Str, &End, 10);
6237    assert(End != Str && "Missing vector size");
6238    Str = End;
6239
6240    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
6241                                             RequiresICE, false);
6242    assert(!RequiresICE && "Can't require vector ICE");
6243
6244    // TODO: No way to make AltiVec vectors in builtins yet.
6245    Type = Context.getVectorType(ElementType, NumElements,
6246                                 VectorType::GenericVector);
6247    break;
6248  }
6249  case 'X': {
6250    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
6251                                             false);
6252    assert(!RequiresICE && "Can't require complex ICE");
6253    Type = Context.getComplexType(ElementType);
6254    break;
6255  }
6256  case 'Y' : {
6257    Type = Context.getPointerDiffType();
6258    break;
6259  }
6260  case 'P':
6261    Type = Context.getFILEType();
6262    if (Type.isNull()) {
6263      Error = ASTContext::GE_Missing_stdio;
6264      return QualType();
6265    }
6266    break;
6267  case 'J':
6268    if (Signed)
6269      Type = Context.getsigjmp_bufType();
6270    else
6271      Type = Context.getjmp_bufType();
6272
6273    if (Type.isNull()) {
6274      Error = ASTContext::GE_Missing_setjmp;
6275      return QualType();
6276    }
6277    break;
6278  }
6279
6280  // If there are modifiers and if we're allowed to parse them, go for it.
6281  Done = !AllowTypeModifiers;
6282  while (!Done) {
6283    switch (char c = *Str++) {
6284    default: Done = true; --Str; break;
6285    case '*':
6286    case '&': {
6287      // Both pointers and references can have their pointee types
6288      // qualified with an address space.
6289      char *End;
6290      unsigned AddrSpace = strtoul(Str, &End, 10);
6291      if (End != Str && AddrSpace != 0) {
6292        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
6293        Str = End;
6294      }
6295      if (c == '*')
6296        Type = Context.getPointerType(Type);
6297      else
6298        Type = Context.getLValueReferenceType(Type);
6299      break;
6300    }
6301    // FIXME: There's no way to have a built-in with an rvalue ref arg.
6302    case 'C':
6303      Type = Type.withConst();
6304      break;
6305    case 'D':
6306      Type = Context.getVolatileType(Type);
6307      break;
6308    }
6309  }
6310
6311  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
6312         "Integer constant 'I' type must be an integer");
6313
6314  return Type;
6315}
6316
6317/// GetBuiltinType - Return the type for the specified builtin.
6318QualType ASTContext::GetBuiltinType(unsigned Id,
6319                                    GetBuiltinTypeError &Error,
6320                                    unsigned *IntegerConstantArgs) const {
6321  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
6322
6323  SmallVector<QualType, 8> ArgTypes;
6324
6325  bool RequiresICE = false;
6326  Error = GE_None;
6327  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
6328                                       RequiresICE, true);
6329  if (Error != GE_None)
6330    return QualType();
6331
6332  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
6333
6334  while (TypeStr[0] && TypeStr[0] != '.') {
6335    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
6336    if (Error != GE_None)
6337      return QualType();
6338
6339    // If this argument is required to be an IntegerConstantExpression and the
6340    // caller cares, fill in the bitmask we return.
6341    if (RequiresICE && IntegerConstantArgs)
6342      *IntegerConstantArgs |= 1 << ArgTypes.size();
6343
6344    // Do array -> pointer decay.  The builtin should use the decayed type.
6345    if (Ty->isArrayType())
6346      Ty = getArrayDecayedType(Ty);
6347
6348    ArgTypes.push_back(Ty);
6349  }
6350
6351  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
6352         "'.' should only occur at end of builtin type list!");
6353
6354  FunctionType::ExtInfo EI;
6355  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
6356
6357  bool Variadic = (TypeStr[0] == '.');
6358
6359  // We really shouldn't be making a no-proto type here, especially in C++.
6360  if (ArgTypes.empty() && Variadic)
6361    return getFunctionNoProtoType(ResType, EI);
6362
6363  FunctionProtoType::ExtProtoInfo EPI;
6364  EPI.ExtInfo = EI;
6365  EPI.Variadic = Variadic;
6366
6367  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(), EPI);
6368}
6369
6370GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
6371  GVALinkage External = GVA_StrongExternal;
6372
6373  Linkage L = FD->getLinkage();
6374  switch (L) {
6375  case NoLinkage:
6376  case InternalLinkage:
6377  case UniqueExternalLinkage:
6378    return GVA_Internal;
6379
6380  case ExternalLinkage:
6381    switch (FD->getTemplateSpecializationKind()) {
6382    case TSK_Undeclared:
6383    case TSK_ExplicitSpecialization:
6384      External = GVA_StrongExternal;
6385      break;
6386
6387    case TSK_ExplicitInstantiationDefinition:
6388      return GVA_ExplicitTemplateInstantiation;
6389
6390    case TSK_ExplicitInstantiationDeclaration:
6391    case TSK_ImplicitInstantiation:
6392      External = GVA_TemplateInstantiation;
6393      break;
6394    }
6395  }
6396
6397  if (!FD->isInlined())
6398    return External;
6399
6400  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
6401    // GNU or C99 inline semantics. Determine whether this symbol should be
6402    // externally visible.
6403    if (FD->isInlineDefinitionExternallyVisible())
6404      return External;
6405
6406    // C99 inline semantics, where the symbol is not externally visible.
6407    return GVA_C99Inline;
6408  }
6409
6410  // C++0x [temp.explicit]p9:
6411  //   [ Note: The intent is that an inline function that is the subject of
6412  //   an explicit instantiation declaration will still be implicitly
6413  //   instantiated when used so that the body can be considered for
6414  //   inlining, but that no out-of-line copy of the inline function would be
6415  //   generated in the translation unit. -- end note ]
6416  if (FD->getTemplateSpecializationKind()
6417                                       == TSK_ExplicitInstantiationDeclaration)
6418    return GVA_C99Inline;
6419
6420  return GVA_CXXInline;
6421}
6422
6423GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
6424  // If this is a static data member, compute the kind of template
6425  // specialization. Otherwise, this variable is not part of a
6426  // template.
6427  TemplateSpecializationKind TSK = TSK_Undeclared;
6428  if (VD->isStaticDataMember())
6429    TSK = VD->getTemplateSpecializationKind();
6430
6431  Linkage L = VD->getLinkage();
6432  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
6433      VD->getType()->getLinkage() == UniqueExternalLinkage)
6434    L = UniqueExternalLinkage;
6435
6436  switch (L) {
6437  case NoLinkage:
6438  case InternalLinkage:
6439  case UniqueExternalLinkage:
6440    return GVA_Internal;
6441
6442  case ExternalLinkage:
6443    switch (TSK) {
6444    case TSK_Undeclared:
6445    case TSK_ExplicitSpecialization:
6446      return GVA_StrongExternal;
6447
6448    case TSK_ExplicitInstantiationDeclaration:
6449      llvm_unreachable("Variable should not be instantiated");
6450      // Fall through to treat this like any other instantiation.
6451
6452    case TSK_ExplicitInstantiationDefinition:
6453      return GVA_ExplicitTemplateInstantiation;
6454
6455    case TSK_ImplicitInstantiation:
6456      return GVA_TemplateInstantiation;
6457    }
6458  }
6459
6460  return GVA_StrongExternal;
6461}
6462
6463bool ASTContext::DeclMustBeEmitted(const Decl *D) {
6464  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
6465    if (!VD->isFileVarDecl())
6466      return false;
6467  } else if (!isa<FunctionDecl>(D))
6468    return false;
6469
6470  // Weak references don't produce any output by themselves.
6471  if (D->hasAttr<WeakRefAttr>())
6472    return false;
6473
6474  // Aliases and used decls are required.
6475  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
6476    return true;
6477
6478  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
6479    // Forward declarations aren't required.
6480    if (!FD->doesThisDeclarationHaveABody())
6481      return FD->doesDeclarationForceExternallyVisibleDefinition();
6482
6483    // Constructors and destructors are required.
6484    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
6485      return true;
6486
6487    // The key function for a class is required.
6488    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
6489      const CXXRecordDecl *RD = MD->getParent();
6490      if (MD->isOutOfLine() && RD->isDynamicClass()) {
6491        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
6492        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
6493          return true;
6494      }
6495    }
6496
6497    GVALinkage Linkage = GetGVALinkageForFunction(FD);
6498
6499    // static, static inline, always_inline, and extern inline functions can
6500    // always be deferred.  Normal inline functions can be deferred in C99/C++.
6501    // Implicit template instantiations can also be deferred in C++.
6502    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
6503        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
6504      return false;
6505    return true;
6506  }
6507
6508  const VarDecl *VD = cast<VarDecl>(D);
6509  assert(VD->isFileVarDecl() && "Expected file scoped var");
6510
6511  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
6512    return false;
6513
6514  // Structs that have non-trivial constructors or destructors are required.
6515
6516  // FIXME: Handle references.
6517  // FIXME: Be more selective about which constructors we care about.
6518  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
6519    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
6520      if (RD->hasDefinition() && !(RD->hasTrivialDefaultConstructor() &&
6521                                   RD->hasTrivialCopyConstructor() &&
6522                                   RD->hasTrivialMoveConstructor() &&
6523                                   RD->hasTrivialDestructor()))
6524        return true;
6525    }
6526  }
6527
6528  GVALinkage L = GetGVALinkageForVariable(VD);
6529  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
6530    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
6531      return false;
6532  }
6533
6534  return true;
6535}
6536
6537CallingConv ASTContext::getDefaultMethodCallConv() {
6538  // Pass through to the C++ ABI object
6539  return ABI->getDefaultMethodCallConv();
6540}
6541
6542bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
6543  // Pass through to the C++ ABI object
6544  return ABI->isNearlyEmpty(RD);
6545}
6546
6547MangleContext *ASTContext::createMangleContext() {
6548  switch (Target->getCXXABI()) {
6549  case CXXABI_ARM:
6550  case CXXABI_Itanium:
6551    return createItaniumMangleContext(*this, getDiagnostics());
6552  case CXXABI_Microsoft:
6553    return createMicrosoftMangleContext(*this, getDiagnostics());
6554  }
6555  llvm_unreachable("Unsupported ABI");
6556}
6557
6558CXXABI::~CXXABI() {}
6559
6560size_t ASTContext::getSideTableAllocatedMemory() const {
6561  return ASTRecordLayouts.getMemorySize()
6562    + llvm::capacity_in_bytes(ObjCLayouts)
6563    + llvm::capacity_in_bytes(KeyFunctions)
6564    + llvm::capacity_in_bytes(ObjCImpls)
6565    + llvm::capacity_in_bytes(BlockVarCopyInits)
6566    + llvm::capacity_in_bytes(DeclAttrs)
6567    + llvm::capacity_in_bytes(InstantiatedFromStaticDataMember)
6568    + llvm::capacity_in_bytes(InstantiatedFromUsingDecl)
6569    + llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl)
6570    + llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl)
6571    + llvm::capacity_in_bytes(OverriddenMethods)
6572    + llvm::capacity_in_bytes(Types)
6573    + llvm::capacity_in_bytes(VariableArrayTypes)
6574    + llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
6575}
6576
6577void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
6578  ParamIndices[D] = index;
6579}
6580
6581unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
6582  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
6583  assert(I != ParamIndices.end() &&
6584         "ParmIndices lacks entry set by ParmVarDecl");
6585  return I->second;
6586}
6587