ASTContext.cpp revision a1b852f8e1bee5ed3604ee483803cef39ce57a20 
1//===--- ASTContext.cpp - Context to hold long-lived AST nodes ------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements the ASTContext interface.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/AST/ASTContext.h"
15#include "clang/AST/CharUnits.h"
16#include "clang/AST/DeclCXX.h"
17#include "clang/AST/DeclObjC.h"
18#include "clang/AST/DeclTemplate.h"
19#include "clang/AST/TypeLoc.h"
20#include "clang/AST/Expr.h"
21#include "clang/AST/ExprCXX.h"
22#include "clang/AST/ExternalASTSource.h"
23#include "clang/AST/ASTMutationListener.h"
24#include "clang/AST/RecordLayout.h"
25#include "clang/AST/Mangle.h"
26#include "clang/Basic/Builtins.h"
27#include "clang/Basic/SourceManager.h"
28#include "clang/Basic/TargetInfo.h"
29#include "llvm/ADT/SmallString.h"
30#include "llvm/ADT/StringExtras.h"
31#include "llvm/Support/MathExtras.h"
32#include "llvm/Support/raw_ostream.h"
33#include "llvm/Support/Capacity.h"
34#include "CXXABI.h"
35#include <map>
36
37using namespace clang;
38
39unsigned ASTContext::NumImplicitDefaultConstructors;
40unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
41unsigned ASTContext::NumImplicitCopyConstructors;
42unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
43unsigned ASTContext::NumImplicitMoveConstructors;
44unsigned ASTContext::NumImplicitMoveConstructorsDeclared;
45unsigned ASTContext::NumImplicitCopyAssignmentOperators;
46unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
47unsigned ASTContext::NumImplicitMoveAssignmentOperators;
48unsigned ASTContext::NumImplicitMoveAssignmentOperatorsDeclared;
49unsigned ASTContext::NumImplicitDestructors;
50unsigned ASTContext::NumImplicitDestructorsDeclared;
51
52enum FloatingRank {
53  HalfRank, FloatRank, DoubleRank, LongDoubleRank
54};
55
56void
57ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
58                                               TemplateTemplateParmDecl *Parm) {
59  ID.AddInteger(Parm->getDepth());
60  ID.AddInteger(Parm->getPosition());
61  ID.AddBoolean(Parm->isParameterPack());
62
63  TemplateParameterList *Params = Parm->getTemplateParameters();
64  ID.AddInteger(Params->size());
65  for (TemplateParameterList::const_iterator P = Params->begin(),
66                                          PEnd = Params->end();
67       P != PEnd; ++P) {
68    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
69      ID.AddInteger(0);
70      ID.AddBoolean(TTP->isParameterPack());
71      continue;
72    }
73
74    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
75      ID.AddInteger(1);
76      ID.AddBoolean(NTTP->isParameterPack());
77      ID.AddPointer(NTTP->getType().getAsOpaquePtr());
78      if (NTTP->isExpandedParameterPack()) {
79        ID.AddBoolean(true);
80        ID.AddInteger(NTTP->getNumExpansionTypes());
81        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I)
82          ID.AddPointer(NTTP->getExpansionType(I).getAsOpaquePtr());
83      } else
84        ID.AddBoolean(false);
85      continue;
86    }
87
88    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
89    ID.AddInteger(2);
90    Profile(ID, TTP);
91  }
92}
93
94TemplateTemplateParmDecl *
95ASTContext::getCanonicalTemplateTemplateParmDecl(
96                                          TemplateTemplateParmDecl *TTP) const {
97  // Check if we already have a canonical template template parameter.
98  llvm::FoldingSetNodeID ID;
99  CanonicalTemplateTemplateParm::Profile(ID, TTP);
100  void *InsertPos = 0;
101  CanonicalTemplateTemplateParm *Canonical
102    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
103  if (Canonical)
104    return Canonical->getParam();
105
106  // Build a canonical template parameter list.
107  TemplateParameterList *Params = TTP->getTemplateParameters();
108  SmallVector<NamedDecl *, 4> CanonParams;
109  CanonParams.reserve(Params->size());
110  for (TemplateParameterList::const_iterator P = Params->begin(),
111                                          PEnd = Params->end();
112       P != PEnd; ++P) {
113    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
114      CanonParams.push_back(
115                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
116                                               SourceLocation(),
117                                               SourceLocation(),
118                                               TTP->getDepth(),
119                                               TTP->getIndex(), 0, false,
120                                               TTP->isParameterPack()));
121    else if (NonTypeTemplateParmDecl *NTTP
122             = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
123      QualType T = getCanonicalType(NTTP->getType());
124      TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
125      NonTypeTemplateParmDecl *Param;
126      if (NTTP->isExpandedParameterPack()) {
127        SmallVector<QualType, 2> ExpandedTypes;
128        SmallVector<TypeSourceInfo *, 2> ExpandedTInfos;
129        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
130          ExpandedTypes.push_back(getCanonicalType(NTTP->getExpansionType(I)));
131          ExpandedTInfos.push_back(
132                                getTrivialTypeSourceInfo(ExpandedTypes.back()));
133        }
134
135        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
136                                                SourceLocation(),
137                                                SourceLocation(),
138                                                NTTP->getDepth(),
139                                                NTTP->getPosition(), 0,
140                                                T,
141                                                TInfo,
142                                                ExpandedTypes.data(),
143                                                ExpandedTypes.size(),
144                                                ExpandedTInfos.data());
145      } else {
146        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
147                                                SourceLocation(),
148                                                SourceLocation(),
149                                                NTTP->getDepth(),
150                                                NTTP->getPosition(), 0,
151                                                T,
152                                                NTTP->isParameterPack(),
153                                                TInfo);
154      }
155      CanonParams.push_back(Param);
156
157    } else
158      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
159                                           cast<TemplateTemplateParmDecl>(*P)));
160  }
161
162  TemplateTemplateParmDecl *CanonTTP
163    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
164                                       SourceLocation(), TTP->getDepth(),
165                                       TTP->getPosition(),
166                                       TTP->isParameterPack(),
167                                       0,
168                         TemplateParameterList::Create(*this, SourceLocation(),
169                                                       SourceLocation(),
170                                                       CanonParams.data(),
171                                                       CanonParams.size(),
172                                                       SourceLocation()));
173
174  // Get the new insert position for the node we care about.
175  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
176  assert(Canonical == 0 && "Shouldn't be in the map!");
177  (void)Canonical;
178
179  // Create the canonical template template parameter entry.
180  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
181  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
182  return CanonTTP;
183}
184
185CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
186  if (!LangOpts.CPlusPlus) return 0;
187
188  switch (T.getCXXABI()) {
189  case CXXABI_ARM:
190    return CreateARMCXXABI(*this);
191  case CXXABI_Itanium:
192    return CreateItaniumCXXABI(*this);
193  case CXXABI_Microsoft:
194    return CreateMicrosoftCXXABI(*this);
195  }
196  return 0;
197}
198
199static const LangAS::Map *getAddressSpaceMap(const TargetInfo &T,
200                                             const LangOptions &LOpts) {
201  if (LOpts.FakeAddressSpaceMap) {
202    // The fake address space map must have a distinct entry for each
203    // language-specific address space.
204    static const unsigned FakeAddrSpaceMap[] = {
205      1, // opencl_global
206      2, // opencl_local
207      3  // opencl_constant
208    };
209    return &FakeAddrSpaceMap;
210  } else {
211    return &T.getAddressSpaceMap();
212  }
213}
214
215ASTContext::ASTContext(LangOptions& LOpts, SourceManager &SM,
216                       const TargetInfo *t,
217                       IdentifierTable &idents, SelectorTable &sels,
218                       Builtin::Context &builtins,
219                       unsigned size_reserve,
220                       bool DelayInitialization)
221  : FunctionProtoTypes(this_()),
222    TemplateSpecializationTypes(this_()),
223    DependentTemplateSpecializationTypes(this_()),
224    SubstTemplateTemplateParmPacks(this_()),
225    GlobalNestedNameSpecifier(0),
226    Int128Decl(0), UInt128Decl(0),
227    ObjCIdDecl(0), ObjCSelDecl(0), ObjCClassDecl(0),
228    CFConstantStringTypeDecl(0), ObjCInstanceTypeDecl(0),
229    FILEDecl(0),
230    jmp_bufDecl(0), sigjmp_bufDecl(0), 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  // Placeholder type for pseudo-objects.
465  InitBuiltinType(PseudoObjectTy,      BuiltinType::PseudoObject);
466
467  // "any" type; useful for debugger-like clients.
468  InitBuiltinType(UnknownAnyTy,        BuiltinType::UnknownAny);
469
470  // Placeholder type for unbridged ARC casts.
471  InitBuiltinType(ARCUnbridgedCastTy,  BuiltinType::ARCUnbridgedCast);
472
473  // C99 6.2.5p11.
474  FloatComplexTy      = getComplexType(FloatTy);
475  DoubleComplexTy     = getComplexType(DoubleTy);
476  LongDoubleComplexTy = getComplexType(LongDoubleTy);
477
478  BuiltinVaListType = QualType();
479
480  // Builtin types for 'id', 'Class', and 'SEL'.
481  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
482  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
483  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
484
485  ObjCConstantStringType = QualType();
486
487  // void * type
488  VoidPtrTy = getPointerType(VoidTy);
489
490  // nullptr type (C++0x 2.14.7)
491  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
492
493  // half type (OpenCL 6.1.1.1) / ARM NEON __fp16
494  InitBuiltinType(HalfTy, BuiltinType::Half);
495}
496
497DiagnosticsEngine &ASTContext::getDiagnostics() const {
498  return SourceMgr.getDiagnostics();
499}
500
501AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
502  AttrVec *&Result = DeclAttrs[D];
503  if (!Result) {
504    void *Mem = Allocate(sizeof(AttrVec));
505    Result = new (Mem) AttrVec;
506  }
507
508  return *Result;
509}
510
511/// \brief Erase the attributes corresponding to the given declaration.
512void ASTContext::eraseDeclAttrs(const Decl *D) {
513  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
514  if (Pos != DeclAttrs.end()) {
515    Pos->second->~AttrVec();
516    DeclAttrs.erase(Pos);
517  }
518}
519
520MemberSpecializationInfo *
521ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
522  assert(Var->isStaticDataMember() && "Not a static data member");
523  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
524    = InstantiatedFromStaticDataMember.find(Var);
525  if (Pos == InstantiatedFromStaticDataMember.end())
526    return 0;
527
528  return Pos->second;
529}
530
531void
532ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
533                                                TemplateSpecializationKind TSK,
534                                          SourceLocation PointOfInstantiation) {
535  assert(Inst->isStaticDataMember() && "Not a static data member");
536  assert(Tmpl->isStaticDataMember() && "Not a static data member");
537  assert(!InstantiatedFromStaticDataMember[Inst] &&
538         "Already noted what static data member was instantiated from");
539  InstantiatedFromStaticDataMember[Inst]
540    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
541}
542
543FunctionDecl *ASTContext::getClassScopeSpecializationPattern(
544                                                     const FunctionDecl *FD){
545  assert(FD && "Specialization is 0");
546  llvm::DenseMap<const FunctionDecl*, FunctionDecl *>::const_iterator Pos
547    = ClassScopeSpecializationPattern.find(FD);
548  if (Pos == ClassScopeSpecializationPattern.end())
549    return 0;
550
551  return Pos->second;
552}
553
554void ASTContext::setClassScopeSpecializationPattern(FunctionDecl *FD,
555                                        FunctionDecl *Pattern) {
556  assert(FD && "Specialization is 0");
557  assert(Pattern && "Class scope specialization pattern is 0");
558  ClassScopeSpecializationPattern[FD] = Pattern;
559}
560
561NamedDecl *
562ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
563  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
564    = InstantiatedFromUsingDecl.find(UUD);
565  if (Pos == InstantiatedFromUsingDecl.end())
566    return 0;
567
568  return Pos->second;
569}
570
571void
572ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
573  assert((isa<UsingDecl>(Pattern) ||
574          isa<UnresolvedUsingValueDecl>(Pattern) ||
575          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
576         "pattern decl is not a using decl");
577  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
578  InstantiatedFromUsingDecl[Inst] = Pattern;
579}
580
581UsingShadowDecl *
582ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
583  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
584    = InstantiatedFromUsingShadowDecl.find(Inst);
585  if (Pos == InstantiatedFromUsingShadowDecl.end())
586    return 0;
587
588  return Pos->second;
589}
590
591void
592ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
593                                               UsingShadowDecl *Pattern) {
594  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
595  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
596}
597
598FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
599  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
600    = InstantiatedFromUnnamedFieldDecl.find(Field);
601  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
602    return 0;
603
604  return Pos->second;
605}
606
607void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
608                                                     FieldDecl *Tmpl) {
609  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
610  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
611  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
612         "Already noted what unnamed field was instantiated from");
613
614  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
615}
616
617bool ASTContext::ZeroBitfieldFollowsNonBitfield(const FieldDecl *FD,
618                                    const FieldDecl *LastFD) const {
619  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
620          FD->getBitWidthValue(*this) == 0);
621}
622
623bool ASTContext::ZeroBitfieldFollowsBitfield(const FieldDecl *FD,
624                                             const FieldDecl *LastFD) const {
625  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
626          FD->getBitWidthValue(*this) == 0 &&
627          LastFD->getBitWidthValue(*this) != 0);
628}
629
630bool ASTContext::BitfieldFollowsBitfield(const FieldDecl *FD,
631                                         const FieldDecl *LastFD) const {
632  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
633          FD->getBitWidthValue(*this) &&
634          LastFD->getBitWidthValue(*this));
635}
636
637bool ASTContext::NonBitfieldFollowsBitfield(const FieldDecl *FD,
638                                         const FieldDecl *LastFD) const {
639  return (!FD->isBitField() && LastFD && LastFD->isBitField() &&
640          LastFD->getBitWidthValue(*this));
641}
642
643bool ASTContext::BitfieldFollowsNonBitfield(const FieldDecl *FD,
644                                             const FieldDecl *LastFD) const {
645  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
646          FD->getBitWidthValue(*this));
647}
648
649ASTContext::overridden_cxx_method_iterator
650ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
651  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
652    = OverriddenMethods.find(Method);
653  if (Pos == OverriddenMethods.end())
654    return 0;
655
656  return Pos->second.begin();
657}
658
659ASTContext::overridden_cxx_method_iterator
660ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
661  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
662    = OverriddenMethods.find(Method);
663  if (Pos == OverriddenMethods.end())
664    return 0;
665
666  return Pos->second.end();
667}
668
669unsigned
670ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
671  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
672    = OverriddenMethods.find(Method);
673  if (Pos == OverriddenMethods.end())
674    return 0;
675
676  return Pos->second.size();
677}
678
679void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
680                                     const CXXMethodDecl *Overridden) {
681  OverriddenMethods[Method].push_back(Overridden);
682}
683
684//===----------------------------------------------------------------------===//
685//                         Type Sizing and Analysis
686//===----------------------------------------------------------------------===//
687
688/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
689/// scalar floating point type.
690const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
691  const BuiltinType *BT = T->getAs<BuiltinType>();
692  assert(BT && "Not a floating point type!");
693  switch (BT->getKind()) {
694  default: llvm_unreachable("Not a floating point type!");
695  case BuiltinType::Half:       return Target->getHalfFormat();
696  case BuiltinType::Float:      return Target->getFloatFormat();
697  case BuiltinType::Double:     return Target->getDoubleFormat();
698  case BuiltinType::LongDouble: return Target->getLongDoubleFormat();
699  }
700}
701
702/// getDeclAlign - Return a conservative estimate of the alignment of the
703/// specified decl.  Note that bitfields do not have a valid alignment, so
704/// this method will assert on them.
705/// If @p RefAsPointee, references are treated like their underlying type
706/// (for alignof), else they're treated like pointers (for CodeGen).
707CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) const {
708  unsigned Align = Target->getCharWidth();
709
710  bool UseAlignAttrOnly = false;
711  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
712    Align = AlignFromAttr;
713
714    // __attribute__((aligned)) can increase or decrease alignment
715    // *except* on a struct or struct member, where it only increases
716    // alignment unless 'packed' is also specified.
717    //
718    // It is an error for alignas to decrease alignment, so we can
719    // ignore that possibility;  Sema should diagnose it.
720    if (isa<FieldDecl>(D)) {
721      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
722        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
723    } else {
724      UseAlignAttrOnly = true;
725    }
726  }
727  else if (isa<FieldDecl>(D))
728      UseAlignAttrOnly =
729        D->hasAttr<PackedAttr>() ||
730        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
731
732  // If we're using the align attribute only, just ignore everything
733  // else about the declaration and its type.
734  if (UseAlignAttrOnly) {
735    // do nothing
736
737  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
738    QualType T = VD->getType();
739    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
740      if (RefAsPointee)
741        T = RT->getPointeeType();
742      else
743        T = getPointerType(RT->getPointeeType());
744    }
745    if (!T->isIncompleteType() && !T->isFunctionType()) {
746      // Adjust alignments of declarations with array type by the
747      // large-array alignment on the target.
748      unsigned MinWidth = Target->getLargeArrayMinWidth();
749      const ArrayType *arrayType;
750      if (MinWidth && (arrayType = getAsArrayType(T))) {
751        if (isa<VariableArrayType>(arrayType))
752          Align = std::max(Align, Target->getLargeArrayAlign());
753        else if (isa<ConstantArrayType>(arrayType) &&
754                 MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
755          Align = std::max(Align, Target->getLargeArrayAlign());
756
757        // Walk through any array types while we're at it.
758        T = getBaseElementType(arrayType);
759      }
760      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
761    }
762
763    // Fields can be subject to extra alignment constraints, like if
764    // the field is packed, the struct is packed, or the struct has a
765    // a max-field-alignment constraint (#pragma pack).  So calculate
766    // the actual alignment of the field within the struct, and then
767    // (as we're expected to) constrain that by the alignment of the type.
768    if (const FieldDecl *field = dyn_cast<FieldDecl>(VD)) {
769      // So calculate the alignment of the field.
770      const ASTRecordLayout &layout = getASTRecordLayout(field->getParent());
771
772      // Start with the record's overall alignment.
773      unsigned fieldAlign = toBits(layout.getAlignment());
774
775      // Use the GCD of that and the offset within the record.
776      uint64_t offset = layout.getFieldOffset(field->getFieldIndex());
777      if (offset > 0) {
778        // Alignment is always a power of 2, so the GCD will be a power of 2,
779        // which means we get to do this crazy thing instead of Euclid's.
780        uint64_t lowBitOfOffset = offset & (~offset + 1);
781        if (lowBitOfOffset < fieldAlign)
782          fieldAlign = static_cast<unsigned>(lowBitOfOffset);
783      }
784
785      Align = std::min(Align, fieldAlign);
786    }
787  }
788
789  return toCharUnitsFromBits(Align);
790}
791
792std::pair<CharUnits, CharUnits>
793ASTContext::getTypeInfoInChars(const Type *T) const {
794  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
795  return std::make_pair(toCharUnitsFromBits(Info.first),
796                        toCharUnitsFromBits(Info.second));
797}
798
799std::pair<CharUnits, CharUnits>
800ASTContext::getTypeInfoInChars(QualType T) const {
801  return getTypeInfoInChars(T.getTypePtr());
802}
803
804/// getTypeSize - Return the size of the specified type, in bits.  This method
805/// does not work on incomplete types.
806///
807/// FIXME: Pointers into different addr spaces could have different sizes and
808/// alignment requirements: getPointerInfo should take an AddrSpace, this
809/// should take a QualType, &c.
810std::pair<uint64_t, unsigned>
811ASTContext::getTypeInfo(const Type *T) const {
812  uint64_t Width=0;
813  unsigned Align=8;
814  switch (T->getTypeClass()) {
815#define TYPE(Class, Base)
816#define ABSTRACT_TYPE(Class, Base)
817#define NON_CANONICAL_TYPE(Class, Base)
818#define DEPENDENT_TYPE(Class, Base) case Type::Class:
819#include "clang/AST/TypeNodes.def"
820    llvm_unreachable("Should not see dependent types");
821    break;
822
823  case Type::FunctionNoProto:
824  case Type::FunctionProto:
825    // GCC extension: alignof(function) = 32 bits
826    Width = 0;
827    Align = 32;
828    break;
829
830  case Type::IncompleteArray:
831  case Type::VariableArray:
832    Width = 0;
833    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
834    break;
835
836  case Type::ConstantArray: {
837    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
838
839    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
840    Width = EltInfo.first*CAT->getSize().getZExtValue();
841    Align = EltInfo.second;
842    Width = llvm::RoundUpToAlignment(Width, Align);
843    break;
844  }
845  case Type::ExtVector:
846  case Type::Vector: {
847    const VectorType *VT = cast<VectorType>(T);
848    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
849    Width = EltInfo.first*VT->getNumElements();
850    Align = Width;
851    // If the alignment is not a power of 2, round up to the next power of 2.
852    // This happens for non-power-of-2 length vectors.
853    if (Align & (Align-1)) {
854      Align = llvm::NextPowerOf2(Align);
855      Width = llvm::RoundUpToAlignment(Width, Align);
856    }
857    break;
858  }
859
860  case Type::Builtin:
861    switch (cast<BuiltinType>(T)->getKind()) {
862    default: llvm_unreachable("Unknown builtin type!");
863    case BuiltinType::Void:
864      // GCC extension: alignof(void) = 8 bits.
865      Width = 0;
866      Align = 8;
867      break;
868
869    case BuiltinType::Bool:
870      Width = Target->getBoolWidth();
871      Align = Target->getBoolAlign();
872      break;
873    case BuiltinType::Char_S:
874    case BuiltinType::Char_U:
875    case BuiltinType::UChar:
876    case BuiltinType::SChar:
877      Width = Target->getCharWidth();
878      Align = Target->getCharAlign();
879      break;
880    case BuiltinType::WChar_S:
881    case BuiltinType::WChar_U:
882      Width = Target->getWCharWidth();
883      Align = Target->getWCharAlign();
884      break;
885    case BuiltinType::Char16:
886      Width = Target->getChar16Width();
887      Align = Target->getChar16Align();
888      break;
889    case BuiltinType::Char32:
890      Width = Target->getChar32Width();
891      Align = Target->getChar32Align();
892      break;
893    case BuiltinType::UShort:
894    case BuiltinType::Short:
895      Width = Target->getShortWidth();
896      Align = Target->getShortAlign();
897      break;
898    case BuiltinType::UInt:
899    case BuiltinType::Int:
900      Width = Target->getIntWidth();
901      Align = Target->getIntAlign();
902      break;
903    case BuiltinType::ULong:
904    case BuiltinType::Long:
905      Width = Target->getLongWidth();
906      Align = Target->getLongAlign();
907      break;
908    case BuiltinType::ULongLong:
909    case BuiltinType::LongLong:
910      Width = Target->getLongLongWidth();
911      Align = Target->getLongLongAlign();
912      break;
913    case BuiltinType::Int128:
914    case BuiltinType::UInt128:
915      Width = 128;
916      Align = 128; // int128_t is 128-bit aligned on all targets.
917      break;
918    case BuiltinType::Half:
919      Width = Target->getHalfWidth();
920      Align = Target->getHalfAlign();
921      break;
922    case BuiltinType::Float:
923      Width = Target->getFloatWidth();
924      Align = Target->getFloatAlign();
925      break;
926    case BuiltinType::Double:
927      Width = Target->getDoubleWidth();
928      Align = Target->getDoubleAlign();
929      break;
930    case BuiltinType::LongDouble:
931      Width = Target->getLongDoubleWidth();
932      Align = Target->getLongDoubleAlign();
933      break;
934    case BuiltinType::NullPtr:
935      Width = Target->getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
936      Align = Target->getPointerAlign(0); //   == sizeof(void*)
937      break;
938    case BuiltinType::ObjCId:
939    case BuiltinType::ObjCClass:
940    case BuiltinType::ObjCSel:
941      Width = Target->getPointerWidth(0);
942      Align = Target->getPointerAlign(0);
943      break;
944    }
945    break;
946  case Type::ObjCObjectPointer:
947    Width = Target->getPointerWidth(0);
948    Align = Target->getPointerAlign(0);
949    break;
950  case Type::BlockPointer: {
951    unsigned AS = getTargetAddressSpace(
952        cast<BlockPointerType>(T)->getPointeeType());
953    Width = Target->getPointerWidth(AS);
954    Align = Target->getPointerAlign(AS);
955    break;
956  }
957  case Type::LValueReference:
958  case Type::RValueReference: {
959    // alignof and sizeof should never enter this code path here, so we go
960    // the pointer route.
961    unsigned AS = getTargetAddressSpace(
962        cast<ReferenceType>(T)->getPointeeType());
963    Width = Target->getPointerWidth(AS);
964    Align = Target->getPointerAlign(AS);
965    break;
966  }
967  case Type::Pointer: {
968    unsigned AS = getTargetAddressSpace(cast<PointerType>(T)->getPointeeType());
969    Width = Target->getPointerWidth(AS);
970    Align = Target->getPointerAlign(AS);
971    break;
972  }
973  case Type::MemberPointer: {
974    const MemberPointerType *MPT = cast<MemberPointerType>(T);
975    std::pair<uint64_t, unsigned> PtrDiffInfo =
976      getTypeInfo(getPointerDiffType());
977    Width = PtrDiffInfo.first * ABI->getMemberPointerSize(MPT);
978    Align = PtrDiffInfo.second;
979    break;
980  }
981  case Type::Complex: {
982    // Complex types have the same alignment as their elements, but twice the
983    // size.
984    std::pair<uint64_t, unsigned> EltInfo =
985      getTypeInfo(cast<ComplexType>(T)->getElementType());
986    Width = EltInfo.first*2;
987    Align = EltInfo.second;
988    break;
989  }
990  case Type::ObjCObject:
991    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
992  case Type::ObjCInterface: {
993    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
994    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
995    Width = toBits(Layout.getSize());
996    Align = toBits(Layout.getAlignment());
997    break;
998  }
999  case Type::Record:
1000  case Type::Enum: {
1001    const TagType *TT = cast<TagType>(T);
1002
1003    if (TT->getDecl()->isInvalidDecl()) {
1004      Width = 8;
1005      Align = 8;
1006      break;
1007    }
1008
1009    if (const EnumType *ET = dyn_cast<EnumType>(TT))
1010      return getTypeInfo(ET->getDecl()->getIntegerType());
1011
1012    const RecordType *RT = cast<RecordType>(TT);
1013    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
1014    Width = toBits(Layout.getSize());
1015    Align = toBits(Layout.getAlignment());
1016    break;
1017  }
1018
1019  case Type::SubstTemplateTypeParm:
1020    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
1021                       getReplacementType().getTypePtr());
1022
1023  case Type::Auto: {
1024    const AutoType *A = cast<AutoType>(T);
1025    assert(A->isDeduced() && "Cannot request the size of a dependent type");
1026    return getTypeInfo(A->getDeducedType().getTypePtr());
1027  }
1028
1029  case Type::Paren:
1030    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
1031
1032  case Type::Typedef: {
1033    const TypedefNameDecl *Typedef = cast<TypedefType>(T)->getDecl();
1034    std::pair<uint64_t, unsigned> Info
1035      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
1036    // If the typedef has an aligned attribute on it, it overrides any computed
1037    // alignment we have.  This violates the GCC documentation (which says that
1038    // attribute(aligned) can only round up) but matches its implementation.
1039    if (unsigned AttrAlign = Typedef->getMaxAlignment())
1040      Align = AttrAlign;
1041    else
1042      Align = Info.second;
1043    Width = Info.first;
1044    break;
1045  }
1046
1047  case Type::TypeOfExpr:
1048    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
1049                         .getTypePtr());
1050
1051  case Type::TypeOf:
1052    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
1053
1054  case Type::Decltype:
1055    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
1056                        .getTypePtr());
1057
1058  case Type::UnaryTransform:
1059    return getTypeInfo(cast<UnaryTransformType>(T)->getUnderlyingType());
1060
1061  case Type::Elaborated:
1062    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
1063
1064  case Type::Attributed:
1065    return getTypeInfo(
1066                  cast<AttributedType>(T)->getEquivalentType().getTypePtr());
1067
1068  case Type::TemplateSpecialization: {
1069    assert(getCanonicalType(T) != T &&
1070           "Cannot request the size of a dependent type");
1071    const TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T);
1072    // A type alias template specialization may refer to a typedef with the
1073    // aligned attribute on it.
1074    if (TST->isTypeAlias())
1075      return getTypeInfo(TST->getAliasedType().getTypePtr());
1076    else
1077      return getTypeInfo(getCanonicalType(T));
1078  }
1079
1080  case Type::Atomic: {
1081    std::pair<uint64_t, unsigned> Info
1082      = getTypeInfo(cast<AtomicType>(T)->getValueType());
1083    Width = Info.first;
1084    Align = Info.second;
1085    if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth() &&
1086        llvm::isPowerOf2_64(Width)) {
1087      // We can potentially perform lock-free atomic operations for this
1088      // type; promote the alignment appropriately.
1089      // FIXME: We could potentially promote the width here as well...
1090      // is that worthwhile?  (Non-struct atomic types generally have
1091      // power-of-two size anyway, but structs might not.  Requires a bit
1092      // of implementation work to make sure we zero out the extra bits.)
1093      Align = static_cast<unsigned>(Width);
1094    }
1095  }
1096
1097  }
1098
1099  assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
1100  return std::make_pair(Width, Align);
1101}
1102
1103/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1104CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1105  return CharUnits::fromQuantity(BitSize / getCharWidth());
1106}
1107
1108/// toBits - Convert a size in characters to a size in characters.
1109int64_t ASTContext::toBits(CharUnits CharSize) const {
1110  return CharSize.getQuantity() * getCharWidth();
1111}
1112
1113/// getTypeSizeInChars - Return the size of the specified type, in characters.
1114/// This method does not work on incomplete types.
1115CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1116  return toCharUnitsFromBits(getTypeSize(T));
1117}
1118CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1119  return toCharUnitsFromBits(getTypeSize(T));
1120}
1121
1122/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1123/// characters. This method does not work on incomplete types.
1124CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1125  return toCharUnitsFromBits(getTypeAlign(T));
1126}
1127CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1128  return toCharUnitsFromBits(getTypeAlign(T));
1129}
1130
1131/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1132/// type for the current target in bits.  This can be different than the ABI
1133/// alignment in cases where it is beneficial for performance to overalign
1134/// a data type.
1135unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1136  unsigned ABIAlign = getTypeAlign(T);
1137
1138  // Double and long long should be naturally aligned if possible.
1139  if (const ComplexType* CT = T->getAs<ComplexType>())
1140    T = CT->getElementType().getTypePtr();
1141  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1142      T->isSpecificBuiltinType(BuiltinType::LongLong))
1143    return std::max(ABIAlign, (unsigned)getTypeSize(T));
1144
1145  return ABIAlign;
1146}
1147
1148/// DeepCollectObjCIvars -
1149/// This routine first collects all declared, but not synthesized, ivars in
1150/// super class and then collects all ivars, including those synthesized for
1151/// current class. This routine is used for implementation of current class
1152/// when all ivars, declared and synthesized are known.
1153///
1154void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1155                                      bool leafClass,
1156                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1157  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1158    DeepCollectObjCIvars(SuperClass, false, Ivars);
1159  if (!leafClass) {
1160    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
1161         E = OI->ivar_end(); I != E; ++I)
1162      Ivars.push_back(*I);
1163  } else {
1164    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1165    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1166         Iv= Iv->getNextIvar())
1167      Ivars.push_back(Iv);
1168  }
1169}
1170
1171/// CollectInheritedProtocols - Collect all protocols in current class and
1172/// those inherited by it.
1173void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1174                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1175  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1176    // We can use protocol_iterator here instead of
1177    // all_referenced_protocol_iterator since we are walking all categories.
1178    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
1179         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
1180      ObjCProtocolDecl *Proto = (*P);
1181      Protocols.insert(Proto);
1182      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1183           PE = Proto->protocol_end(); P != PE; ++P) {
1184        Protocols.insert(*P);
1185        CollectInheritedProtocols(*P, Protocols);
1186      }
1187    }
1188
1189    // Categories of this Interface.
1190    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
1191         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
1192      CollectInheritedProtocols(CDeclChain, Protocols);
1193    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1194      while (SD) {
1195        CollectInheritedProtocols(SD, Protocols);
1196        SD = SD->getSuperClass();
1197      }
1198  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1199    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
1200         PE = OC->protocol_end(); P != PE; ++P) {
1201      ObjCProtocolDecl *Proto = (*P);
1202      Protocols.insert(Proto);
1203      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1204           PE = Proto->protocol_end(); P != PE; ++P)
1205        CollectInheritedProtocols(*P, Protocols);
1206    }
1207  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
1208    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
1209         PE = OP->protocol_end(); P != PE; ++P) {
1210      ObjCProtocolDecl *Proto = (*P);
1211      Protocols.insert(Proto);
1212      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1213           PE = Proto->protocol_end(); P != PE; ++P)
1214        CollectInheritedProtocols(*P, Protocols);
1215    }
1216  }
1217}
1218
1219unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
1220  unsigned count = 0;
1221  // Count ivars declared in class extension.
1222  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
1223       CDecl = CDecl->getNextClassExtension())
1224    count += CDecl->ivar_size();
1225
1226  // Count ivar defined in this class's implementation.  This
1227  // includes synthesized ivars.
1228  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
1229    count += ImplDecl->ivar_size();
1230
1231  return count;
1232}
1233
1234/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
1235ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
1236  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1237    I = ObjCImpls.find(D);
1238  if (I != ObjCImpls.end())
1239    return cast<ObjCImplementationDecl>(I->second);
1240  return 0;
1241}
1242/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
1243ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
1244  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1245    I = ObjCImpls.find(D);
1246  if (I != ObjCImpls.end())
1247    return cast<ObjCCategoryImplDecl>(I->second);
1248  return 0;
1249}
1250
1251/// \brief Set the implementation of ObjCInterfaceDecl.
1252void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1253                           ObjCImplementationDecl *ImplD) {
1254  assert(IFaceD && ImplD && "Passed null params");
1255  ObjCImpls[IFaceD] = ImplD;
1256}
1257/// \brief Set the implementation of ObjCCategoryDecl.
1258void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1259                           ObjCCategoryImplDecl *ImplD) {
1260  assert(CatD && ImplD && "Passed null params");
1261  ObjCImpls[CatD] = ImplD;
1262}
1263
1264/// \brief Get the copy initialization expression of VarDecl,or NULL if
1265/// none exists.
1266Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
1267  assert(VD && "Passed null params");
1268  assert(VD->hasAttr<BlocksAttr>() &&
1269         "getBlockVarCopyInits - not __block var");
1270  llvm::DenseMap<const VarDecl*, Expr*>::iterator
1271    I = BlockVarCopyInits.find(VD);
1272  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : 0;
1273}
1274
1275/// \brief Set the copy inialization expression of a block var decl.
1276void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
1277  assert(VD && Init && "Passed null params");
1278  assert(VD->hasAttr<BlocksAttr>() &&
1279         "setBlockVarCopyInits - not __block var");
1280  BlockVarCopyInits[VD] = Init;
1281}
1282
1283/// \brief Allocate an uninitialized TypeSourceInfo.
1284///
1285/// The caller should initialize the memory held by TypeSourceInfo using
1286/// the TypeLoc wrappers.
1287///
1288/// \param T the type that will be the basis for type source info. This type
1289/// should refer to how the declarator was written in source code, not to
1290/// what type semantic analysis resolved the declarator to.
1291TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1292                                                 unsigned DataSize) const {
1293  if (!DataSize)
1294    DataSize = TypeLoc::getFullDataSizeForType(T);
1295  else
1296    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1297           "incorrect data size provided to CreateTypeSourceInfo!");
1298
1299  TypeSourceInfo *TInfo =
1300    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1301  new (TInfo) TypeSourceInfo(T);
1302  return TInfo;
1303}
1304
1305TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1306                                                     SourceLocation L) const {
1307  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1308  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
1309  return DI;
1310}
1311
1312const ASTRecordLayout &
1313ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
1314  return getObjCLayout(D, 0);
1315}
1316
1317const ASTRecordLayout &
1318ASTContext::getASTObjCImplementationLayout(
1319                                        const ObjCImplementationDecl *D) const {
1320  return getObjCLayout(D->getClassInterface(), D);
1321}
1322
1323//===----------------------------------------------------------------------===//
1324//                   Type creation/memoization methods
1325//===----------------------------------------------------------------------===//
1326
1327QualType
1328ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
1329  unsigned fastQuals = quals.getFastQualifiers();
1330  quals.removeFastQualifiers();
1331
1332  // Check if we've already instantiated this type.
1333  llvm::FoldingSetNodeID ID;
1334  ExtQuals::Profile(ID, baseType, quals);
1335  void *insertPos = 0;
1336  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
1337    assert(eq->getQualifiers() == quals);
1338    return QualType(eq, fastQuals);
1339  }
1340
1341  // If the base type is not canonical, make the appropriate canonical type.
1342  QualType canon;
1343  if (!baseType->isCanonicalUnqualified()) {
1344    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
1345    canonSplit.second.addConsistentQualifiers(quals);
1346    canon = getExtQualType(canonSplit.first, canonSplit.second);
1347
1348    // Re-find the insert position.
1349    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
1350  }
1351
1352  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
1353  ExtQualNodes.InsertNode(eq, insertPos);
1354  return QualType(eq, fastQuals);
1355}
1356
1357QualType
1358ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
1359  QualType CanT = getCanonicalType(T);
1360  if (CanT.getAddressSpace() == AddressSpace)
1361    return T;
1362
1363  // If we are composing extended qualifiers together, merge together
1364  // into one ExtQuals node.
1365  QualifierCollector Quals;
1366  const Type *TypeNode = Quals.strip(T);
1367
1368  // If this type already has an address space specified, it cannot get
1369  // another one.
1370  assert(!Quals.hasAddressSpace() &&
1371         "Type cannot be in multiple addr spaces!");
1372  Quals.addAddressSpace(AddressSpace);
1373
1374  return getExtQualType(TypeNode, Quals);
1375}
1376
1377QualType ASTContext::getObjCGCQualType(QualType T,
1378                                       Qualifiers::GC GCAttr) const {
1379  QualType CanT = getCanonicalType(T);
1380  if (CanT.getObjCGCAttr() == GCAttr)
1381    return T;
1382
1383  if (const PointerType *ptr = T->getAs<PointerType>()) {
1384    QualType Pointee = ptr->getPointeeType();
1385    if (Pointee->isAnyPointerType()) {
1386      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1387      return getPointerType(ResultType);
1388    }
1389  }
1390
1391  // If we are composing extended qualifiers together, merge together
1392  // into one ExtQuals node.
1393  QualifierCollector Quals;
1394  const Type *TypeNode = Quals.strip(T);
1395
1396  // If this type already has an ObjCGC specified, it cannot get
1397  // another one.
1398  assert(!Quals.hasObjCGCAttr() &&
1399         "Type cannot have multiple ObjCGCs!");
1400  Quals.addObjCGCAttr(GCAttr);
1401
1402  return getExtQualType(TypeNode, Quals);
1403}
1404
1405const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
1406                                                   FunctionType::ExtInfo Info) {
1407  if (T->getExtInfo() == Info)
1408    return T;
1409
1410  QualType Result;
1411  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
1412    Result = getFunctionNoProtoType(FNPT->getResultType(), Info);
1413  } else {
1414    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
1415    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
1416    EPI.ExtInfo = Info;
1417    Result = getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1418                             FPT->getNumArgs(), EPI);
1419  }
1420
1421  return cast<FunctionType>(Result.getTypePtr());
1422}
1423
1424/// getComplexType - Return the uniqued reference to the type for a complex
1425/// number with the specified element type.
1426QualType ASTContext::getComplexType(QualType T) const {
1427  // Unique pointers, to guarantee there is only one pointer of a particular
1428  // structure.
1429  llvm::FoldingSetNodeID ID;
1430  ComplexType::Profile(ID, T);
1431
1432  void *InsertPos = 0;
1433  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1434    return QualType(CT, 0);
1435
1436  // If the pointee type isn't canonical, this won't be a canonical type either,
1437  // so fill in the canonical type field.
1438  QualType Canonical;
1439  if (!T.isCanonical()) {
1440    Canonical = getComplexType(getCanonicalType(T));
1441
1442    // Get the new insert position for the node we care about.
1443    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1444    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1445  }
1446  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1447  Types.push_back(New);
1448  ComplexTypes.InsertNode(New, InsertPos);
1449  return QualType(New, 0);
1450}
1451
1452/// getPointerType - Return the uniqued reference to the type for a pointer to
1453/// the specified type.
1454QualType ASTContext::getPointerType(QualType T) const {
1455  // Unique pointers, to guarantee there is only one pointer of a particular
1456  // structure.
1457  llvm::FoldingSetNodeID ID;
1458  PointerType::Profile(ID, T);
1459
1460  void *InsertPos = 0;
1461  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1462    return QualType(PT, 0);
1463
1464  // If the pointee type isn't canonical, this won't be a canonical type either,
1465  // so fill in the canonical type field.
1466  QualType Canonical;
1467  if (!T.isCanonical()) {
1468    Canonical = getPointerType(getCanonicalType(T));
1469
1470    // Get the new insert position for the node we care about.
1471    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1472    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1473  }
1474  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1475  Types.push_back(New);
1476  PointerTypes.InsertNode(New, InsertPos);
1477  return QualType(New, 0);
1478}
1479
1480/// getBlockPointerType - Return the uniqued reference to the type for
1481/// a pointer to the specified block.
1482QualType ASTContext::getBlockPointerType(QualType T) const {
1483  assert(T->isFunctionType() && "block of function types only");
1484  // Unique pointers, to guarantee there is only one block of a particular
1485  // structure.
1486  llvm::FoldingSetNodeID ID;
1487  BlockPointerType::Profile(ID, T);
1488
1489  void *InsertPos = 0;
1490  if (BlockPointerType *PT =
1491        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1492    return QualType(PT, 0);
1493
1494  // If the block pointee type isn't canonical, this won't be a canonical
1495  // type either so fill in the canonical type field.
1496  QualType Canonical;
1497  if (!T.isCanonical()) {
1498    Canonical = getBlockPointerType(getCanonicalType(T));
1499
1500    // Get the new insert position for the node we care about.
1501    BlockPointerType *NewIP =
1502      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1503    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1504  }
1505  BlockPointerType *New
1506    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1507  Types.push_back(New);
1508  BlockPointerTypes.InsertNode(New, InsertPos);
1509  return QualType(New, 0);
1510}
1511
1512/// getLValueReferenceType - Return the uniqued reference to the type for an
1513/// lvalue reference to the specified type.
1514QualType
1515ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
1516  assert(getCanonicalType(T) != OverloadTy &&
1517         "Unresolved overloaded function type");
1518
1519  // Unique pointers, to guarantee there is only one pointer of a particular
1520  // structure.
1521  llvm::FoldingSetNodeID ID;
1522  ReferenceType::Profile(ID, T, SpelledAsLValue);
1523
1524  void *InsertPos = 0;
1525  if (LValueReferenceType *RT =
1526        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1527    return QualType(RT, 0);
1528
1529  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1530
1531  // If the referencee type isn't canonical, this won't be a canonical type
1532  // either, so fill in the canonical type field.
1533  QualType Canonical;
1534  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1535    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1536    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1537
1538    // Get the new insert position for the node we care about.
1539    LValueReferenceType *NewIP =
1540      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1541    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1542  }
1543
1544  LValueReferenceType *New
1545    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1546                                                     SpelledAsLValue);
1547  Types.push_back(New);
1548  LValueReferenceTypes.InsertNode(New, InsertPos);
1549
1550  return QualType(New, 0);
1551}
1552
1553/// getRValueReferenceType - Return the uniqued reference to the type for an
1554/// rvalue reference to the specified type.
1555QualType ASTContext::getRValueReferenceType(QualType T) const {
1556  // Unique pointers, to guarantee there is only one pointer of a particular
1557  // structure.
1558  llvm::FoldingSetNodeID ID;
1559  ReferenceType::Profile(ID, T, false);
1560
1561  void *InsertPos = 0;
1562  if (RValueReferenceType *RT =
1563        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1564    return QualType(RT, 0);
1565
1566  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1567
1568  // If the referencee type isn't canonical, this won't be a canonical type
1569  // either, so fill in the canonical type field.
1570  QualType Canonical;
1571  if (InnerRef || !T.isCanonical()) {
1572    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1573    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1574
1575    // Get the new insert position for the node we care about.
1576    RValueReferenceType *NewIP =
1577      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1578    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1579  }
1580
1581  RValueReferenceType *New
1582    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1583  Types.push_back(New);
1584  RValueReferenceTypes.InsertNode(New, InsertPos);
1585  return QualType(New, 0);
1586}
1587
1588/// getMemberPointerType - Return the uniqued reference to the type for a
1589/// member pointer to the specified type, in the specified class.
1590QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
1591  // Unique pointers, to guarantee there is only one pointer of a particular
1592  // structure.
1593  llvm::FoldingSetNodeID ID;
1594  MemberPointerType::Profile(ID, T, Cls);
1595
1596  void *InsertPos = 0;
1597  if (MemberPointerType *PT =
1598      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1599    return QualType(PT, 0);
1600
1601  // If the pointee or class type isn't canonical, this won't be a canonical
1602  // type either, so fill in the canonical type field.
1603  QualType Canonical;
1604  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1605    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1606
1607    // Get the new insert position for the node we care about.
1608    MemberPointerType *NewIP =
1609      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1610    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1611  }
1612  MemberPointerType *New
1613    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1614  Types.push_back(New);
1615  MemberPointerTypes.InsertNode(New, InsertPos);
1616  return QualType(New, 0);
1617}
1618
1619/// getConstantArrayType - Return the unique reference to the type for an
1620/// array of the specified element type.
1621QualType ASTContext::getConstantArrayType(QualType EltTy,
1622                                          const llvm::APInt &ArySizeIn,
1623                                          ArrayType::ArraySizeModifier ASM,
1624                                          unsigned IndexTypeQuals) const {
1625  assert((EltTy->isDependentType() ||
1626          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1627         "Constant array of VLAs is illegal!");
1628
1629  // Convert the array size into a canonical width matching the pointer size for
1630  // the target.
1631  llvm::APInt ArySize(ArySizeIn);
1632  ArySize =
1633    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
1634
1635  llvm::FoldingSetNodeID ID;
1636  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
1637
1638  void *InsertPos = 0;
1639  if (ConstantArrayType *ATP =
1640      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1641    return QualType(ATP, 0);
1642
1643  // If the element type isn't canonical or has qualifiers, this won't
1644  // be a canonical type either, so fill in the canonical type field.
1645  QualType Canon;
1646  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1647    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1648    Canon = getConstantArrayType(QualType(canonSplit.first, 0), ArySize,
1649                                 ASM, IndexTypeQuals);
1650    Canon = getQualifiedType(Canon, canonSplit.second);
1651
1652    // Get the new insert position for the node we care about.
1653    ConstantArrayType *NewIP =
1654      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1655    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1656  }
1657
1658  ConstantArrayType *New = new(*this,TypeAlignment)
1659    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
1660  ConstantArrayTypes.InsertNode(New, InsertPos);
1661  Types.push_back(New);
1662  return QualType(New, 0);
1663}
1664
1665/// getVariableArrayDecayedType - Turns the given type, which may be
1666/// variably-modified, into the corresponding type with all the known
1667/// sizes replaced with [*].
1668QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
1669  // Vastly most common case.
1670  if (!type->isVariablyModifiedType()) return type;
1671
1672  QualType result;
1673
1674  SplitQualType split = type.getSplitDesugaredType();
1675  const Type *ty = split.first;
1676  switch (ty->getTypeClass()) {
1677#define TYPE(Class, Base)
1678#define ABSTRACT_TYPE(Class, Base)
1679#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
1680#include "clang/AST/TypeNodes.def"
1681    llvm_unreachable("didn't desugar past all non-canonical types?");
1682
1683  // These types should never be variably-modified.
1684  case Type::Builtin:
1685  case Type::Complex:
1686  case Type::Vector:
1687  case Type::ExtVector:
1688  case Type::DependentSizedExtVector:
1689  case Type::ObjCObject:
1690  case Type::ObjCInterface:
1691  case Type::ObjCObjectPointer:
1692  case Type::Record:
1693  case Type::Enum:
1694  case Type::UnresolvedUsing:
1695  case Type::TypeOfExpr:
1696  case Type::TypeOf:
1697  case Type::Decltype:
1698  case Type::UnaryTransform:
1699  case Type::DependentName:
1700  case Type::InjectedClassName:
1701  case Type::TemplateSpecialization:
1702  case Type::DependentTemplateSpecialization:
1703  case Type::TemplateTypeParm:
1704  case Type::SubstTemplateTypeParmPack:
1705  case Type::Auto:
1706  case Type::PackExpansion:
1707    llvm_unreachable("type should never be variably-modified");
1708
1709  // These types can be variably-modified but should never need to
1710  // further decay.
1711  case Type::FunctionNoProto:
1712  case Type::FunctionProto:
1713  case Type::BlockPointer:
1714  case Type::MemberPointer:
1715    return type;
1716
1717  // These types can be variably-modified.  All these modifications
1718  // preserve structure except as noted by comments.
1719  // TODO: if we ever care about optimizing VLAs, there are no-op
1720  // optimizations available here.
1721  case Type::Pointer:
1722    result = getPointerType(getVariableArrayDecayedType(
1723                              cast<PointerType>(ty)->getPointeeType()));
1724    break;
1725
1726  case Type::LValueReference: {
1727    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
1728    result = getLValueReferenceType(
1729                 getVariableArrayDecayedType(lv->getPointeeType()),
1730                                    lv->isSpelledAsLValue());
1731    break;
1732  }
1733
1734  case Type::RValueReference: {
1735    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
1736    result = getRValueReferenceType(
1737                 getVariableArrayDecayedType(lv->getPointeeType()));
1738    break;
1739  }
1740
1741  case Type::Atomic: {
1742    const AtomicType *at = cast<AtomicType>(ty);
1743    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
1744    break;
1745  }
1746
1747  case Type::ConstantArray: {
1748    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
1749    result = getConstantArrayType(
1750                 getVariableArrayDecayedType(cat->getElementType()),
1751                                  cat->getSize(),
1752                                  cat->getSizeModifier(),
1753                                  cat->getIndexTypeCVRQualifiers());
1754    break;
1755  }
1756
1757  case Type::DependentSizedArray: {
1758    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
1759    result = getDependentSizedArrayType(
1760                 getVariableArrayDecayedType(dat->getElementType()),
1761                                        dat->getSizeExpr(),
1762                                        dat->getSizeModifier(),
1763                                        dat->getIndexTypeCVRQualifiers(),
1764                                        dat->getBracketsRange());
1765    break;
1766  }
1767
1768  // Turn incomplete types into [*] types.
1769  case Type::IncompleteArray: {
1770    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
1771    result = getVariableArrayType(
1772                 getVariableArrayDecayedType(iat->getElementType()),
1773                                  /*size*/ 0,
1774                                  ArrayType::Normal,
1775                                  iat->getIndexTypeCVRQualifiers(),
1776                                  SourceRange());
1777    break;
1778  }
1779
1780  // Turn VLA types into [*] types.
1781  case Type::VariableArray: {
1782    const VariableArrayType *vat = cast<VariableArrayType>(ty);
1783    result = getVariableArrayType(
1784                 getVariableArrayDecayedType(vat->getElementType()),
1785                                  /*size*/ 0,
1786                                  ArrayType::Star,
1787                                  vat->getIndexTypeCVRQualifiers(),
1788                                  vat->getBracketsRange());
1789    break;
1790  }
1791  }
1792
1793  // Apply the top-level qualifiers from the original.
1794  return getQualifiedType(result, split.second);
1795}
1796
1797/// getVariableArrayType - Returns a non-unique reference to the type for a
1798/// variable array of the specified element type.
1799QualType ASTContext::getVariableArrayType(QualType EltTy,
1800                                          Expr *NumElts,
1801                                          ArrayType::ArraySizeModifier ASM,
1802                                          unsigned IndexTypeQuals,
1803                                          SourceRange Brackets) const {
1804  // Since we don't unique expressions, it isn't possible to unique VLA's
1805  // that have an expression provided for their size.
1806  QualType Canon;
1807
1808  // Be sure to pull qualifiers off the element type.
1809  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1810    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1811    Canon = getVariableArrayType(QualType(canonSplit.first, 0), NumElts, ASM,
1812                                 IndexTypeQuals, Brackets);
1813    Canon = getQualifiedType(Canon, canonSplit.second);
1814  }
1815
1816  VariableArrayType *New = new(*this, TypeAlignment)
1817    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
1818
1819  VariableArrayTypes.push_back(New);
1820  Types.push_back(New);
1821  return QualType(New, 0);
1822}
1823
1824/// getDependentSizedArrayType - Returns a non-unique reference to
1825/// the type for a dependently-sized array of the specified element
1826/// type.
1827QualType ASTContext::getDependentSizedArrayType(QualType elementType,
1828                                                Expr *numElements,
1829                                                ArrayType::ArraySizeModifier ASM,
1830                                                unsigned elementTypeQuals,
1831                                                SourceRange brackets) const {
1832  assert((!numElements || numElements->isTypeDependent() ||
1833          numElements->isValueDependent()) &&
1834         "Size must be type- or value-dependent!");
1835
1836  // Dependently-sized array types that do not have a specified number
1837  // of elements will have their sizes deduced from a dependent
1838  // initializer.  We do no canonicalization here at all, which is okay
1839  // because they can't be used in most locations.
1840  if (!numElements) {
1841    DependentSizedArrayType *newType
1842      = new (*this, TypeAlignment)
1843          DependentSizedArrayType(*this, elementType, QualType(),
1844                                  numElements, ASM, elementTypeQuals,
1845                                  brackets);
1846    Types.push_back(newType);
1847    return QualType(newType, 0);
1848  }
1849
1850  // Otherwise, we actually build a new type every time, but we
1851  // also build a canonical type.
1852
1853  SplitQualType canonElementType = getCanonicalType(elementType).split();
1854
1855  void *insertPos = 0;
1856  llvm::FoldingSetNodeID ID;
1857  DependentSizedArrayType::Profile(ID, *this,
1858                                   QualType(canonElementType.first, 0),
1859                                   ASM, elementTypeQuals, numElements);
1860
1861  // Look for an existing type with these properties.
1862  DependentSizedArrayType *canonTy =
1863    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1864
1865  // If we don't have one, build one.
1866  if (!canonTy) {
1867    canonTy = new (*this, TypeAlignment)
1868      DependentSizedArrayType(*this, QualType(canonElementType.first, 0),
1869                              QualType(), numElements, ASM, elementTypeQuals,
1870                              brackets);
1871    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
1872    Types.push_back(canonTy);
1873  }
1874
1875  // Apply qualifiers from the element type to the array.
1876  QualType canon = getQualifiedType(QualType(canonTy,0),
1877                                    canonElementType.second);
1878
1879  // If we didn't need extra canonicalization for the element type,
1880  // then just use that as our result.
1881  if (QualType(canonElementType.first, 0) == elementType)
1882    return canon;
1883
1884  // Otherwise, we need to build a type which follows the spelling
1885  // of the element type.
1886  DependentSizedArrayType *sugaredType
1887    = new (*this, TypeAlignment)
1888        DependentSizedArrayType(*this, elementType, canon, numElements,
1889                                ASM, elementTypeQuals, brackets);
1890  Types.push_back(sugaredType);
1891  return QualType(sugaredType, 0);
1892}
1893
1894QualType ASTContext::getIncompleteArrayType(QualType elementType,
1895                                            ArrayType::ArraySizeModifier ASM,
1896                                            unsigned elementTypeQuals) const {
1897  llvm::FoldingSetNodeID ID;
1898  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
1899
1900  void *insertPos = 0;
1901  if (IncompleteArrayType *iat =
1902       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
1903    return QualType(iat, 0);
1904
1905  // If the element type isn't canonical, this won't be a canonical type
1906  // either, so fill in the canonical type field.  We also have to pull
1907  // qualifiers off the element type.
1908  QualType canon;
1909
1910  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
1911    SplitQualType canonSplit = getCanonicalType(elementType).split();
1912    canon = getIncompleteArrayType(QualType(canonSplit.first, 0),
1913                                   ASM, elementTypeQuals);
1914    canon = getQualifiedType(canon, canonSplit.second);
1915
1916    // Get the new insert position for the node we care about.
1917    IncompleteArrayType *existing =
1918      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1919    assert(!existing && "Shouldn't be in the map!"); (void) existing;
1920  }
1921
1922  IncompleteArrayType *newType = new (*this, TypeAlignment)
1923    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
1924
1925  IncompleteArrayTypes.InsertNode(newType, insertPos);
1926  Types.push_back(newType);
1927  return QualType(newType, 0);
1928}
1929
1930/// getVectorType - Return the unique reference to a vector type of
1931/// the specified element type and size. VectorType must be a built-in type.
1932QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1933                                   VectorType::VectorKind VecKind) const {
1934  assert(vecType->isBuiltinType());
1935
1936  // Check if we've already instantiated a vector of this type.
1937  llvm::FoldingSetNodeID ID;
1938  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
1939
1940  void *InsertPos = 0;
1941  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1942    return QualType(VTP, 0);
1943
1944  // If the element type isn't canonical, this won't be a canonical type either,
1945  // so fill in the canonical type field.
1946  QualType Canonical;
1947  if (!vecType.isCanonical()) {
1948    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
1949
1950    // Get the new insert position for the node we care about.
1951    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1952    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1953  }
1954  VectorType *New = new (*this, TypeAlignment)
1955    VectorType(vecType, NumElts, Canonical, VecKind);
1956  VectorTypes.InsertNode(New, InsertPos);
1957  Types.push_back(New);
1958  return QualType(New, 0);
1959}
1960
1961/// getExtVectorType - Return the unique reference to an extended vector type of
1962/// the specified element type and size. VectorType must be a built-in type.
1963QualType
1964ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
1965  assert(vecType->isBuiltinType() || vecType->isDependentType());
1966
1967  // Check if we've already instantiated a vector of this type.
1968  llvm::FoldingSetNodeID ID;
1969  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1970                      VectorType::GenericVector);
1971  void *InsertPos = 0;
1972  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1973    return QualType(VTP, 0);
1974
1975  // If the element type isn't canonical, this won't be a canonical type either,
1976  // so fill in the canonical type field.
1977  QualType Canonical;
1978  if (!vecType.isCanonical()) {
1979    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
1980
1981    // Get the new insert position for the node we care about.
1982    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1983    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1984  }
1985  ExtVectorType *New = new (*this, TypeAlignment)
1986    ExtVectorType(vecType, NumElts, Canonical);
1987  VectorTypes.InsertNode(New, InsertPos);
1988  Types.push_back(New);
1989  return QualType(New, 0);
1990}
1991
1992QualType
1993ASTContext::getDependentSizedExtVectorType(QualType vecType,
1994                                           Expr *SizeExpr,
1995                                           SourceLocation AttrLoc) const {
1996  llvm::FoldingSetNodeID ID;
1997  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
1998                                       SizeExpr);
1999
2000  void *InsertPos = 0;
2001  DependentSizedExtVectorType *Canon
2002    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2003  DependentSizedExtVectorType *New;
2004  if (Canon) {
2005    // We already have a canonical version of this array type; use it as
2006    // the canonical type for a newly-built type.
2007    New = new (*this, TypeAlignment)
2008      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
2009                                  SizeExpr, AttrLoc);
2010  } else {
2011    QualType CanonVecTy = getCanonicalType(vecType);
2012    if (CanonVecTy == vecType) {
2013      New = new (*this, TypeAlignment)
2014        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
2015                                    AttrLoc);
2016
2017      DependentSizedExtVectorType *CanonCheck
2018        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2019      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
2020      (void)CanonCheck;
2021      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
2022    } else {
2023      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
2024                                                      SourceLocation());
2025      New = new (*this, TypeAlignment)
2026        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2027    }
2028  }
2029
2030  Types.push_back(New);
2031  return QualType(New, 0);
2032}
2033
2034/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
2035///
2036QualType
2037ASTContext::getFunctionNoProtoType(QualType ResultTy,
2038                                   const FunctionType::ExtInfo &Info) const {
2039  const CallingConv DefaultCC = Info.getCC();
2040  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2041                               CC_X86StdCall : DefaultCC;
2042  // Unique functions, to guarantee there is only one function of a particular
2043  // structure.
2044  llvm::FoldingSetNodeID ID;
2045  FunctionNoProtoType::Profile(ID, ResultTy, Info);
2046
2047  void *InsertPos = 0;
2048  if (FunctionNoProtoType *FT =
2049        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2050    return QualType(FT, 0);
2051
2052  QualType Canonical;
2053  if (!ResultTy.isCanonical() ||
2054      getCanonicalCallConv(CallConv) != CallConv) {
2055    Canonical =
2056      getFunctionNoProtoType(getCanonicalType(ResultTy),
2057                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
2058
2059    // Get the new insert position for the node we care about.
2060    FunctionNoProtoType *NewIP =
2061      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2062    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2063  }
2064
2065  FunctionProtoType::ExtInfo newInfo = Info.withCallingConv(CallConv);
2066  FunctionNoProtoType *New = new (*this, TypeAlignment)
2067    FunctionNoProtoType(ResultTy, Canonical, newInfo);
2068  Types.push_back(New);
2069  FunctionNoProtoTypes.InsertNode(New, InsertPos);
2070  return QualType(New, 0);
2071}
2072
2073/// getFunctionType - Return a normal function type with a typed argument
2074/// list.  isVariadic indicates whether the argument list includes '...'.
2075QualType
2076ASTContext::getFunctionType(QualType ResultTy,
2077                            const QualType *ArgArray, unsigned NumArgs,
2078                            const FunctionProtoType::ExtProtoInfo &EPI) const {
2079  // Unique functions, to guarantee there is only one function of a particular
2080  // structure.
2081  llvm::FoldingSetNodeID ID;
2082  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, EPI, *this);
2083
2084  void *InsertPos = 0;
2085  if (FunctionProtoType *FTP =
2086        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2087    return QualType(FTP, 0);
2088
2089  // Determine whether the type being created is already canonical or not.
2090  bool isCanonical= EPI.ExceptionSpecType == EST_None && ResultTy.isCanonical();
2091  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
2092    if (!ArgArray[i].isCanonicalAsParam())
2093      isCanonical = false;
2094
2095  const CallingConv DefaultCC = EPI.ExtInfo.getCC();
2096  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2097                               CC_X86StdCall : DefaultCC;
2098
2099  // If this type isn't canonical, get the canonical version of it.
2100  // The exception spec is not part of the canonical type.
2101  QualType Canonical;
2102  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
2103    SmallVector<QualType, 16> CanonicalArgs;
2104    CanonicalArgs.reserve(NumArgs);
2105    for (unsigned i = 0; i != NumArgs; ++i)
2106      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
2107
2108    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
2109    CanonicalEPI.ExceptionSpecType = EST_None;
2110    CanonicalEPI.NumExceptions = 0;
2111    CanonicalEPI.ExtInfo
2112      = CanonicalEPI.ExtInfo.withCallingConv(getCanonicalCallConv(CallConv));
2113
2114    Canonical = getFunctionType(getCanonicalType(ResultTy),
2115                                CanonicalArgs.data(), NumArgs,
2116                                CanonicalEPI);
2117
2118    // Get the new insert position for the node we care about.
2119    FunctionProtoType *NewIP =
2120      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2121    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2122  }
2123
2124  // FunctionProtoType objects are allocated with extra bytes after
2125  // them for three variable size arrays at the end:
2126  //  - parameter types
2127  //  - exception types
2128  //  - consumed-arguments flags
2129  // Instead of the exception types, there could be a noexcept
2130  // expression.
2131  size_t Size = sizeof(FunctionProtoType) +
2132                NumArgs * sizeof(QualType);
2133  if (EPI.ExceptionSpecType == EST_Dynamic)
2134    Size += EPI.NumExceptions * sizeof(QualType);
2135  else if (EPI.ExceptionSpecType == EST_ComputedNoexcept) {
2136    Size += sizeof(Expr*);
2137  }
2138  if (EPI.ConsumedArguments)
2139    Size += NumArgs * sizeof(bool);
2140
2141  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
2142  FunctionProtoType::ExtProtoInfo newEPI = EPI;
2143  newEPI.ExtInfo = EPI.ExtInfo.withCallingConv(CallConv);
2144  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, Canonical, newEPI);
2145  Types.push_back(FTP);
2146  FunctionProtoTypes.InsertNode(FTP, InsertPos);
2147  return QualType(FTP, 0);
2148}
2149
2150#ifndef NDEBUG
2151static bool NeedsInjectedClassNameType(const RecordDecl *D) {
2152  if (!isa<CXXRecordDecl>(D)) return false;
2153  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
2154  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
2155    return true;
2156  if (RD->getDescribedClassTemplate() &&
2157      !isa<ClassTemplateSpecializationDecl>(RD))
2158    return true;
2159  return false;
2160}
2161#endif
2162
2163/// getInjectedClassNameType - Return the unique reference to the
2164/// injected class name type for the specified templated declaration.
2165QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
2166                                              QualType TST) const {
2167  assert(NeedsInjectedClassNameType(Decl));
2168  if (Decl->TypeForDecl) {
2169    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2170  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDeclaration()) {
2171    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
2172    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2173    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2174  } else {
2175    Type *newType =
2176      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
2177    Decl->TypeForDecl = newType;
2178    Types.push_back(newType);
2179  }
2180  return QualType(Decl->TypeForDecl, 0);
2181}
2182
2183/// getTypeDeclType - Return the unique reference to the type for the
2184/// specified type declaration.
2185QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) const {
2186  assert(Decl && "Passed null for Decl param");
2187  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
2188
2189  if (const TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Decl))
2190    return getTypedefType(Typedef);
2191
2192  assert(!isa<TemplateTypeParmDecl>(Decl) &&
2193         "Template type parameter types are always available.");
2194
2195  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
2196    assert(!Record->getPreviousDeclaration() &&
2197           "struct/union has previous declaration");
2198    assert(!NeedsInjectedClassNameType(Record));
2199    return getRecordType(Record);
2200  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
2201    assert(!Enum->getPreviousDeclaration() &&
2202           "enum has previous declaration");
2203    return getEnumType(Enum);
2204  } else if (const UnresolvedUsingTypenameDecl *Using =
2205               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
2206    Type *newType = new (*this, TypeAlignment) UnresolvedUsingType(Using);
2207    Decl->TypeForDecl = newType;
2208    Types.push_back(newType);
2209  } else
2210    llvm_unreachable("TypeDecl without a type?");
2211
2212  return QualType(Decl->TypeForDecl, 0);
2213}
2214
2215/// getTypedefType - Return the unique reference to the type for the
2216/// specified typedef name decl.
2217QualType
2218ASTContext::getTypedefType(const TypedefNameDecl *Decl,
2219                           QualType Canonical) const {
2220  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2221
2222  if (Canonical.isNull())
2223    Canonical = getCanonicalType(Decl->getUnderlyingType());
2224  TypedefType *newType = new(*this, TypeAlignment)
2225    TypedefType(Type::Typedef, Decl, Canonical);
2226  Decl->TypeForDecl = newType;
2227  Types.push_back(newType);
2228  return QualType(newType, 0);
2229}
2230
2231QualType ASTContext::getRecordType(const RecordDecl *Decl) const {
2232  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2233
2234  if (const RecordDecl *PrevDecl = Decl->getPreviousDeclaration())
2235    if (PrevDecl->TypeForDecl)
2236      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2237
2238  RecordType *newType = new (*this, TypeAlignment) RecordType(Decl);
2239  Decl->TypeForDecl = newType;
2240  Types.push_back(newType);
2241  return QualType(newType, 0);
2242}
2243
2244QualType ASTContext::getEnumType(const EnumDecl *Decl) const {
2245  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2246
2247  if (const EnumDecl *PrevDecl = Decl->getPreviousDeclaration())
2248    if (PrevDecl->TypeForDecl)
2249      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2250
2251  EnumType *newType = new (*this, TypeAlignment) EnumType(Decl);
2252  Decl->TypeForDecl = newType;
2253  Types.push_back(newType);
2254  return QualType(newType, 0);
2255}
2256
2257QualType ASTContext::getAttributedType(AttributedType::Kind attrKind,
2258                                       QualType modifiedType,
2259                                       QualType equivalentType) {
2260  llvm::FoldingSetNodeID id;
2261  AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
2262
2263  void *insertPos = 0;
2264  AttributedType *type = AttributedTypes.FindNodeOrInsertPos(id, insertPos);
2265  if (type) return QualType(type, 0);
2266
2267  QualType canon = getCanonicalType(equivalentType);
2268  type = new (*this, TypeAlignment)
2269           AttributedType(canon, attrKind, modifiedType, equivalentType);
2270
2271  Types.push_back(type);
2272  AttributedTypes.InsertNode(type, insertPos);
2273
2274  return QualType(type, 0);
2275}
2276
2277
2278/// \brief Retrieve a substitution-result type.
2279QualType
2280ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
2281                                         QualType Replacement) const {
2282  assert(Replacement.isCanonical()
2283         && "replacement types must always be canonical");
2284
2285  llvm::FoldingSetNodeID ID;
2286  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
2287  void *InsertPos = 0;
2288  SubstTemplateTypeParmType *SubstParm
2289    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2290
2291  if (!SubstParm) {
2292    SubstParm = new (*this, TypeAlignment)
2293      SubstTemplateTypeParmType(Parm, Replacement);
2294    Types.push_back(SubstParm);
2295    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2296  }
2297
2298  return QualType(SubstParm, 0);
2299}
2300
2301/// \brief Retrieve a
2302QualType ASTContext::getSubstTemplateTypeParmPackType(
2303                                          const TemplateTypeParmType *Parm,
2304                                              const TemplateArgument &ArgPack) {
2305#ifndef NDEBUG
2306  for (TemplateArgument::pack_iterator P = ArgPack.pack_begin(),
2307                                    PEnd = ArgPack.pack_end();
2308       P != PEnd; ++P) {
2309    assert(P->getKind() == TemplateArgument::Type &&"Pack contains a non-type");
2310    assert(P->getAsType().isCanonical() && "Pack contains non-canonical type");
2311  }
2312#endif
2313
2314  llvm::FoldingSetNodeID ID;
2315  SubstTemplateTypeParmPackType::Profile(ID, Parm, ArgPack);
2316  void *InsertPos = 0;
2317  if (SubstTemplateTypeParmPackType *SubstParm
2318        = SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos))
2319    return QualType(SubstParm, 0);
2320
2321  QualType Canon;
2322  if (!Parm->isCanonicalUnqualified()) {
2323    Canon = getCanonicalType(QualType(Parm, 0));
2324    Canon = getSubstTemplateTypeParmPackType(cast<TemplateTypeParmType>(Canon),
2325                                             ArgPack);
2326    SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos);
2327  }
2328
2329  SubstTemplateTypeParmPackType *SubstParm
2330    = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
2331                                                               ArgPack);
2332  Types.push_back(SubstParm);
2333  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2334  return QualType(SubstParm, 0);
2335}
2336
2337/// \brief Retrieve the template type parameter type for a template
2338/// parameter or parameter pack with the given depth, index, and (optionally)
2339/// name.
2340QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
2341                                             bool ParameterPack,
2342                                             TemplateTypeParmDecl *TTPDecl) const {
2343  llvm::FoldingSetNodeID ID;
2344  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, TTPDecl);
2345  void *InsertPos = 0;
2346  TemplateTypeParmType *TypeParm
2347    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2348
2349  if (TypeParm)
2350    return QualType(TypeParm, 0);
2351
2352  if (TTPDecl) {
2353    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
2354    TypeParm = new (*this, TypeAlignment) TemplateTypeParmType(TTPDecl, Canon);
2355
2356    TemplateTypeParmType *TypeCheck
2357      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2358    assert(!TypeCheck && "Template type parameter canonical type broken");
2359    (void)TypeCheck;
2360  } else
2361    TypeParm = new (*this, TypeAlignment)
2362      TemplateTypeParmType(Depth, Index, ParameterPack);
2363
2364  Types.push_back(TypeParm);
2365  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
2366
2367  return QualType(TypeParm, 0);
2368}
2369
2370TypeSourceInfo *
2371ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
2372                                              SourceLocation NameLoc,
2373                                        const TemplateArgumentListInfo &Args,
2374                                              QualType Underlying) const {
2375  assert(!Name.getAsDependentTemplateName() &&
2376         "No dependent template names here!");
2377  QualType TST = getTemplateSpecializationType(Name, Args, Underlying);
2378
2379  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
2380  TemplateSpecializationTypeLoc TL
2381    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
2382  TL.setTemplateNameLoc(NameLoc);
2383  TL.setLAngleLoc(Args.getLAngleLoc());
2384  TL.setRAngleLoc(Args.getRAngleLoc());
2385  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
2386    TL.setArgLocInfo(i, Args[i].getLocInfo());
2387  return DI;
2388}
2389
2390QualType
2391ASTContext::getTemplateSpecializationType(TemplateName Template,
2392                                          const TemplateArgumentListInfo &Args,
2393                                          QualType Underlying) const {
2394  assert(!Template.getAsDependentTemplateName() &&
2395         "No dependent template names here!");
2396
2397  unsigned NumArgs = Args.size();
2398
2399  SmallVector<TemplateArgument, 4> ArgVec;
2400  ArgVec.reserve(NumArgs);
2401  for (unsigned i = 0; i != NumArgs; ++i)
2402    ArgVec.push_back(Args[i].getArgument());
2403
2404  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
2405                                       Underlying);
2406}
2407
2408QualType
2409ASTContext::getTemplateSpecializationType(TemplateName Template,
2410                                          const TemplateArgument *Args,
2411                                          unsigned NumArgs,
2412                                          QualType Underlying) const {
2413  assert(!Template.getAsDependentTemplateName() &&
2414         "No dependent template names here!");
2415  // Look through qualified template names.
2416  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2417    Template = TemplateName(QTN->getTemplateDecl());
2418
2419  bool isTypeAlias =
2420    Template.getAsTemplateDecl() &&
2421    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
2422
2423  QualType CanonType;
2424  if (!Underlying.isNull())
2425    CanonType = getCanonicalType(Underlying);
2426  else {
2427    assert(!isTypeAlias &&
2428           "Underlying type for template alias must be computed by caller");
2429    CanonType = getCanonicalTemplateSpecializationType(Template, Args,
2430                                                       NumArgs);
2431  }
2432
2433  // Allocate the (non-canonical) template specialization type, but don't
2434  // try to unique it: these types typically have location information that
2435  // we don't unique and don't want to lose.
2436  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
2437                       sizeof(TemplateArgument) * NumArgs +
2438                       (isTypeAlias ? sizeof(QualType) : 0),
2439                       TypeAlignment);
2440  TemplateSpecializationType *Spec
2441    = new (Mem) TemplateSpecializationType(Template,
2442                                           Args, NumArgs,
2443                                           CanonType,
2444                                         isTypeAlias ? Underlying : QualType());
2445
2446  Types.push_back(Spec);
2447  return QualType(Spec, 0);
2448}
2449
2450QualType
2451ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
2452                                                   const TemplateArgument *Args,
2453                                                   unsigned NumArgs) const {
2454  assert(!Template.getAsDependentTemplateName() &&
2455         "No dependent template names here!");
2456  assert((!Template.getAsTemplateDecl() ||
2457          !isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl())) &&
2458         "Underlying type for template alias must be computed by caller");
2459
2460  // Look through qualified template names.
2461  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2462    Template = TemplateName(QTN->getTemplateDecl());
2463
2464  // Build the canonical template specialization type.
2465  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
2466  SmallVector<TemplateArgument, 4> CanonArgs;
2467  CanonArgs.reserve(NumArgs);
2468  for (unsigned I = 0; I != NumArgs; ++I)
2469    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
2470
2471  // Determine whether this canonical template specialization type already
2472  // exists.
2473  llvm::FoldingSetNodeID ID;
2474  TemplateSpecializationType::Profile(ID, CanonTemplate,
2475                                      CanonArgs.data(), NumArgs, *this);
2476
2477  void *InsertPos = 0;
2478  TemplateSpecializationType *Spec
2479    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2480
2481  if (!Spec) {
2482    // Allocate a new canonical template specialization type.
2483    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2484                          sizeof(TemplateArgument) * NumArgs),
2485                         TypeAlignment);
2486    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
2487                                                CanonArgs.data(), NumArgs,
2488                                                QualType(), QualType());
2489    Types.push_back(Spec);
2490    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
2491  }
2492
2493  assert(Spec->isDependentType() &&
2494         "Non-dependent template-id type must have a canonical type");
2495  return QualType(Spec, 0);
2496}
2497
2498QualType
2499ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
2500                              NestedNameSpecifier *NNS,
2501                              QualType NamedType) const {
2502  llvm::FoldingSetNodeID ID;
2503  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2504
2505  void *InsertPos = 0;
2506  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2507  if (T)
2508    return QualType(T, 0);
2509
2510  QualType Canon = NamedType;
2511  if (!Canon.isCanonical()) {
2512    Canon = getCanonicalType(NamedType);
2513    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2514    assert(!CheckT && "Elaborated canonical type broken");
2515    (void)CheckT;
2516  }
2517
2518  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2519  Types.push_back(T);
2520  ElaboratedTypes.InsertNode(T, InsertPos);
2521  return QualType(T, 0);
2522}
2523
2524QualType
2525ASTContext::getParenType(QualType InnerType) const {
2526  llvm::FoldingSetNodeID ID;
2527  ParenType::Profile(ID, InnerType);
2528
2529  void *InsertPos = 0;
2530  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2531  if (T)
2532    return QualType(T, 0);
2533
2534  QualType Canon = InnerType;
2535  if (!Canon.isCanonical()) {
2536    Canon = getCanonicalType(InnerType);
2537    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2538    assert(!CheckT && "Paren canonical type broken");
2539    (void)CheckT;
2540  }
2541
2542  T = new (*this) ParenType(InnerType, Canon);
2543  Types.push_back(T);
2544  ParenTypes.InsertNode(T, InsertPos);
2545  return QualType(T, 0);
2546}
2547
2548QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2549                                          NestedNameSpecifier *NNS,
2550                                          const IdentifierInfo *Name,
2551                                          QualType Canon) const {
2552  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2553
2554  if (Canon.isNull()) {
2555    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2556    ElaboratedTypeKeyword CanonKeyword = Keyword;
2557    if (Keyword == ETK_None)
2558      CanonKeyword = ETK_Typename;
2559
2560    if (CanonNNS != NNS || CanonKeyword != Keyword)
2561      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2562  }
2563
2564  llvm::FoldingSetNodeID ID;
2565  DependentNameType::Profile(ID, Keyword, NNS, Name);
2566
2567  void *InsertPos = 0;
2568  DependentNameType *T
2569    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2570  if (T)
2571    return QualType(T, 0);
2572
2573  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2574  Types.push_back(T);
2575  DependentNameTypes.InsertNode(T, InsertPos);
2576  return QualType(T, 0);
2577}
2578
2579QualType
2580ASTContext::getDependentTemplateSpecializationType(
2581                                 ElaboratedTypeKeyword Keyword,
2582                                 NestedNameSpecifier *NNS,
2583                                 const IdentifierInfo *Name,
2584                                 const TemplateArgumentListInfo &Args) const {
2585  // TODO: avoid this copy
2586  SmallVector<TemplateArgument, 16> ArgCopy;
2587  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2588    ArgCopy.push_back(Args[I].getArgument());
2589  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2590                                                ArgCopy.size(),
2591                                                ArgCopy.data());
2592}
2593
2594QualType
2595ASTContext::getDependentTemplateSpecializationType(
2596                                 ElaboratedTypeKeyword Keyword,
2597                                 NestedNameSpecifier *NNS,
2598                                 const IdentifierInfo *Name,
2599                                 unsigned NumArgs,
2600                                 const TemplateArgument *Args) const {
2601  assert((!NNS || NNS->isDependent()) &&
2602         "nested-name-specifier must be dependent");
2603
2604  llvm::FoldingSetNodeID ID;
2605  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2606                                               Name, NumArgs, Args);
2607
2608  void *InsertPos = 0;
2609  DependentTemplateSpecializationType *T
2610    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2611  if (T)
2612    return QualType(T, 0);
2613
2614  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2615
2616  ElaboratedTypeKeyword CanonKeyword = Keyword;
2617  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2618
2619  bool AnyNonCanonArgs = false;
2620  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2621  for (unsigned I = 0; I != NumArgs; ++I) {
2622    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2623    if (!CanonArgs[I].structurallyEquals(Args[I]))
2624      AnyNonCanonArgs = true;
2625  }
2626
2627  QualType Canon;
2628  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2629    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2630                                                   Name, NumArgs,
2631                                                   CanonArgs.data());
2632
2633    // Find the insert position again.
2634    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2635  }
2636
2637  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2638                        sizeof(TemplateArgument) * NumArgs),
2639                       TypeAlignment);
2640  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2641                                                    Name, NumArgs, Args, Canon);
2642  Types.push_back(T);
2643  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2644  return QualType(T, 0);
2645}
2646
2647QualType ASTContext::getPackExpansionType(QualType Pattern,
2648                                      llvm::Optional<unsigned> NumExpansions) {
2649  llvm::FoldingSetNodeID ID;
2650  PackExpansionType::Profile(ID, Pattern, NumExpansions);
2651
2652  assert(Pattern->containsUnexpandedParameterPack() &&
2653         "Pack expansions must expand one or more parameter packs");
2654  void *InsertPos = 0;
2655  PackExpansionType *T
2656    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2657  if (T)
2658    return QualType(T, 0);
2659
2660  QualType Canon;
2661  if (!Pattern.isCanonical()) {
2662    Canon = getPackExpansionType(getCanonicalType(Pattern), NumExpansions);
2663
2664    // Find the insert position again.
2665    PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2666  }
2667
2668  T = new (*this) PackExpansionType(Pattern, Canon, NumExpansions);
2669  Types.push_back(T);
2670  PackExpansionTypes.InsertNode(T, InsertPos);
2671  return QualType(T, 0);
2672}
2673
2674/// CmpProtocolNames - Comparison predicate for sorting protocols
2675/// alphabetically.
2676static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2677                            const ObjCProtocolDecl *RHS) {
2678  return LHS->getDeclName() < RHS->getDeclName();
2679}
2680
2681static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2682                                unsigned NumProtocols) {
2683  if (NumProtocols == 0) return true;
2684
2685  for (unsigned i = 1; i != NumProtocols; ++i)
2686    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]))
2687      return false;
2688  return true;
2689}
2690
2691static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2692                                   unsigned &NumProtocols) {
2693  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2694
2695  // Sort protocols, keyed by name.
2696  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2697
2698  // Remove duplicates.
2699  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2700  NumProtocols = ProtocolsEnd-Protocols;
2701}
2702
2703QualType ASTContext::getObjCObjectType(QualType BaseType,
2704                                       ObjCProtocolDecl * const *Protocols,
2705                                       unsigned NumProtocols) const {
2706  // If the base type is an interface and there aren't any protocols
2707  // to add, then the interface type will do just fine.
2708  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2709    return BaseType;
2710
2711  // Look in the folding set for an existing type.
2712  llvm::FoldingSetNodeID ID;
2713  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2714  void *InsertPos = 0;
2715  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2716    return QualType(QT, 0);
2717
2718  // Build the canonical type, which has the canonical base type and
2719  // a sorted-and-uniqued list of protocols.
2720  QualType Canonical;
2721  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2722  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2723    if (!ProtocolsSorted) {
2724      SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2725                                                     Protocols + NumProtocols);
2726      unsigned UniqueCount = NumProtocols;
2727
2728      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2729      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2730                                    &Sorted[0], UniqueCount);
2731    } else {
2732      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2733                                    Protocols, NumProtocols);
2734    }
2735
2736    // Regenerate InsertPos.
2737    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2738  }
2739
2740  unsigned Size = sizeof(ObjCObjectTypeImpl);
2741  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2742  void *Mem = Allocate(Size, TypeAlignment);
2743  ObjCObjectTypeImpl *T =
2744    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2745
2746  Types.push_back(T);
2747  ObjCObjectTypes.InsertNode(T, InsertPos);
2748  return QualType(T, 0);
2749}
2750
2751/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2752/// the given object type.
2753QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
2754  llvm::FoldingSetNodeID ID;
2755  ObjCObjectPointerType::Profile(ID, ObjectT);
2756
2757  void *InsertPos = 0;
2758  if (ObjCObjectPointerType *QT =
2759              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2760    return QualType(QT, 0);
2761
2762  // Find the canonical object type.
2763  QualType Canonical;
2764  if (!ObjectT.isCanonical()) {
2765    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2766
2767    // Regenerate InsertPos.
2768    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2769  }
2770
2771  // No match.
2772  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2773  ObjCObjectPointerType *QType =
2774    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2775
2776  Types.push_back(QType);
2777  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2778  return QualType(QType, 0);
2779}
2780
2781/// getObjCInterfaceType - Return the unique reference to the type for the
2782/// specified ObjC interface decl. The list of protocols is optional.
2783QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl) const {
2784  if (Decl->TypeForDecl)
2785    return QualType(Decl->TypeForDecl, 0);
2786
2787  // FIXME: redeclarations?
2788  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2789  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2790  Decl->TypeForDecl = T;
2791  Types.push_back(T);
2792  return QualType(T, 0);
2793}
2794
2795/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2796/// TypeOfExprType AST's (since expression's are never shared). For example,
2797/// multiple declarations that refer to "typeof(x)" all contain different
2798/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2799/// on canonical type's (which are always unique).
2800QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
2801  TypeOfExprType *toe;
2802  if (tofExpr->isTypeDependent()) {
2803    llvm::FoldingSetNodeID ID;
2804    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2805
2806    void *InsertPos = 0;
2807    DependentTypeOfExprType *Canon
2808      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2809    if (Canon) {
2810      // We already have a "canonical" version of an identical, dependent
2811      // typeof(expr) type. Use that as our canonical type.
2812      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2813                                          QualType((TypeOfExprType*)Canon, 0));
2814    } else {
2815      // Build a new, canonical typeof(expr) type.
2816      Canon
2817        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2818      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2819      toe = Canon;
2820    }
2821  } else {
2822    QualType Canonical = getCanonicalType(tofExpr->getType());
2823    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2824  }
2825  Types.push_back(toe);
2826  return QualType(toe, 0);
2827}
2828
2829/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2830/// TypeOfType AST's. The only motivation to unique these nodes would be
2831/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2832/// an issue. This doesn't effect the type checker, since it operates
2833/// on canonical type's (which are always unique).
2834QualType ASTContext::getTypeOfType(QualType tofType) const {
2835  QualType Canonical = getCanonicalType(tofType);
2836  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2837  Types.push_back(tot);
2838  return QualType(tot, 0);
2839}
2840
2841/// getDecltypeForExpr - Given an expr, will return the decltype for that
2842/// expression, according to the rules in C++0x [dcl.type.simple]p4
2843static QualType getDecltypeForExpr(const Expr *e, const ASTContext &Context) {
2844  if (e->isTypeDependent())
2845    return Context.DependentTy;
2846
2847  // If e is an id expression or a class member access, decltype(e) is defined
2848  // as the type of the entity named by e.
2849  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2850    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2851      return VD->getType();
2852  }
2853  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2854    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2855      return FD->getType();
2856  }
2857  // If e is a function call or an invocation of an overloaded operator,
2858  // (parentheses around e are ignored), decltype(e) is defined as the
2859  // return type of that function.
2860  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2861    return CE->getCallReturnType();
2862
2863  QualType T = e->getType();
2864
2865  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2866  // defined as T&, otherwise decltype(e) is defined as T.
2867  if (e->isLValue())
2868    T = Context.getLValueReferenceType(T);
2869
2870  return T;
2871}
2872
2873/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2874/// DecltypeType AST's. The only motivation to unique these nodes would be
2875/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2876/// an issue. This doesn't effect the type checker, since it operates
2877/// on canonical type's (which are always unique).
2878QualType ASTContext::getDecltypeType(Expr *e) const {
2879  DecltypeType *dt;
2880
2881  // C++0x [temp.type]p2:
2882  //   If an expression e involves a template parameter, decltype(e) denotes a
2883  //   unique dependent type. Two such decltype-specifiers refer to the same
2884  //   type only if their expressions are equivalent (14.5.6.1).
2885  if (e->isInstantiationDependent()) {
2886    llvm::FoldingSetNodeID ID;
2887    DependentDecltypeType::Profile(ID, *this, e);
2888
2889    void *InsertPos = 0;
2890    DependentDecltypeType *Canon
2891      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2892    if (Canon) {
2893      // We already have a "canonical" version of an equivalent, dependent
2894      // decltype type. Use that as our canonical type.
2895      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2896                                       QualType((DecltypeType*)Canon, 0));
2897    } else {
2898      // Build a new, canonical typeof(expr) type.
2899      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2900      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2901      dt = Canon;
2902    }
2903  } else {
2904    QualType T = getDecltypeForExpr(e, *this);
2905    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2906  }
2907  Types.push_back(dt);
2908  return QualType(dt, 0);
2909}
2910
2911/// getUnaryTransformationType - We don't unique these, since the memory
2912/// savings are minimal and these are rare.
2913QualType ASTContext::getUnaryTransformType(QualType BaseType,
2914                                           QualType UnderlyingType,
2915                                           UnaryTransformType::UTTKind Kind)
2916    const {
2917  UnaryTransformType *Ty =
2918    new (*this, TypeAlignment) UnaryTransformType (BaseType, UnderlyingType,
2919                                                   Kind,
2920                                 UnderlyingType->isDependentType() ?
2921                                    QualType() : UnderlyingType);
2922  Types.push_back(Ty);
2923  return QualType(Ty, 0);
2924}
2925
2926/// getAutoType - We only unique auto types after they've been deduced.
2927QualType ASTContext::getAutoType(QualType DeducedType) const {
2928  void *InsertPos = 0;
2929  if (!DeducedType.isNull()) {
2930    // Look in the folding set for an existing type.
2931    llvm::FoldingSetNodeID ID;
2932    AutoType::Profile(ID, DeducedType);
2933    if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
2934      return QualType(AT, 0);
2935  }
2936
2937  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType);
2938  Types.push_back(AT);
2939  if (InsertPos)
2940    AutoTypes.InsertNode(AT, InsertPos);
2941  return QualType(AT, 0);
2942}
2943
2944/// getAtomicType - Return the uniqued reference to the atomic type for
2945/// the given value type.
2946QualType ASTContext::getAtomicType(QualType T) const {
2947  // Unique pointers, to guarantee there is only one pointer of a particular
2948  // structure.
2949  llvm::FoldingSetNodeID ID;
2950  AtomicType::Profile(ID, T);
2951
2952  void *InsertPos = 0;
2953  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
2954    return QualType(AT, 0);
2955
2956  // If the atomic value type isn't canonical, this won't be a canonical type
2957  // either, so fill in the canonical type field.
2958  QualType Canonical;
2959  if (!T.isCanonical()) {
2960    Canonical = getAtomicType(getCanonicalType(T));
2961
2962    // Get the new insert position for the node we care about.
2963    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
2964    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2965  }
2966  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
2967  Types.push_back(New);
2968  AtomicTypes.InsertNode(New, InsertPos);
2969  return QualType(New, 0);
2970}
2971
2972/// getAutoDeductType - Get type pattern for deducing against 'auto'.
2973QualType ASTContext::getAutoDeductType() const {
2974  if (AutoDeductTy.isNull())
2975    AutoDeductTy = getAutoType(QualType());
2976  assert(!AutoDeductTy.isNull() && "can't build 'auto' pattern");
2977  return AutoDeductTy;
2978}
2979
2980/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
2981QualType ASTContext::getAutoRRefDeductType() const {
2982  if (AutoRRefDeductTy.isNull())
2983    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
2984  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
2985  return AutoRRefDeductTy;
2986}
2987
2988/// getTagDeclType - Return the unique reference to the type for the
2989/// specified TagDecl (struct/union/class/enum) decl.
2990QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
2991  assert (Decl);
2992  // FIXME: What is the design on getTagDeclType when it requires casting
2993  // away const?  mutable?
2994  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2995}
2996
2997/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2998/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2999/// needs to agree with the definition in <stddef.h>.
3000CanQualType ASTContext::getSizeType() const {
3001  return getFromTargetType(Target->getSizeType());
3002}
3003
3004/// getSignedWCharType - Return the type of "signed wchar_t".
3005/// Used when in C++, as a GCC extension.
3006QualType ASTContext::getSignedWCharType() const {
3007  // FIXME: derive from "Target" ?
3008  return WCharTy;
3009}
3010
3011/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
3012/// Used when in C++, as a GCC extension.
3013QualType ASTContext::getUnsignedWCharType() const {
3014  // FIXME: derive from "Target" ?
3015  return UnsignedIntTy;
3016}
3017
3018/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
3019/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
3020QualType ASTContext::getPointerDiffType() const {
3021  return getFromTargetType(Target->getPtrDiffType(0));
3022}
3023
3024//===----------------------------------------------------------------------===//
3025//                              Type Operators
3026//===----------------------------------------------------------------------===//
3027
3028CanQualType ASTContext::getCanonicalParamType(QualType T) const {
3029  // Push qualifiers into arrays, and then discard any remaining
3030  // qualifiers.
3031  T = getCanonicalType(T);
3032  T = getVariableArrayDecayedType(T);
3033  const Type *Ty = T.getTypePtr();
3034  QualType Result;
3035  if (isa<ArrayType>(Ty)) {
3036    Result = getArrayDecayedType(QualType(Ty,0));
3037  } else if (isa<FunctionType>(Ty)) {
3038    Result = getPointerType(QualType(Ty, 0));
3039  } else {
3040    Result = QualType(Ty, 0);
3041  }
3042
3043  return CanQualType::CreateUnsafe(Result);
3044}
3045
3046QualType ASTContext::getUnqualifiedArrayType(QualType type,
3047                                             Qualifiers &quals) {
3048  SplitQualType splitType = type.getSplitUnqualifiedType();
3049
3050  // FIXME: getSplitUnqualifiedType() actually walks all the way to
3051  // the unqualified desugared type and then drops it on the floor.
3052  // We then have to strip that sugar back off with
3053  // getUnqualifiedDesugaredType(), which is silly.
3054  const ArrayType *AT =
3055    dyn_cast<ArrayType>(splitType.first->getUnqualifiedDesugaredType());
3056
3057  // If we don't have an array, just use the results in splitType.
3058  if (!AT) {
3059    quals = splitType.second;
3060    return QualType(splitType.first, 0);
3061  }
3062
3063  // Otherwise, recurse on the array's element type.
3064  QualType elementType = AT->getElementType();
3065  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
3066
3067  // If that didn't change the element type, AT has no qualifiers, so we
3068  // can just use the results in splitType.
3069  if (elementType == unqualElementType) {
3070    assert(quals.empty()); // from the recursive call
3071    quals = splitType.second;
3072    return QualType(splitType.first, 0);
3073  }
3074
3075  // Otherwise, add in the qualifiers from the outermost type, then
3076  // build the type back up.
3077  quals.addConsistentQualifiers(splitType.second);
3078
3079  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
3080    return getConstantArrayType(unqualElementType, CAT->getSize(),
3081                                CAT->getSizeModifier(), 0);
3082  }
3083
3084  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
3085    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
3086  }
3087
3088  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
3089    return getVariableArrayType(unqualElementType,
3090                                VAT->getSizeExpr(),
3091                                VAT->getSizeModifier(),
3092                                VAT->getIndexTypeCVRQualifiers(),
3093                                VAT->getBracketsRange());
3094  }
3095
3096  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
3097  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
3098                                    DSAT->getSizeModifier(), 0,
3099                                    SourceRange());
3100}
3101
3102/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
3103/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
3104/// they point to and return true. If T1 and T2 aren't pointer types
3105/// or pointer-to-member types, or if they are not similar at this
3106/// level, returns false and leaves T1 and T2 unchanged. Top-level
3107/// qualifiers on T1 and T2 are ignored. This function will typically
3108/// be called in a loop that successively "unwraps" pointer and
3109/// pointer-to-member types to compare them at each level.
3110bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
3111  const PointerType *T1PtrType = T1->getAs<PointerType>(),
3112                    *T2PtrType = T2->getAs<PointerType>();
3113  if (T1PtrType && T2PtrType) {
3114    T1 = T1PtrType->getPointeeType();
3115    T2 = T2PtrType->getPointeeType();
3116    return true;
3117  }
3118
3119  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
3120                          *T2MPType = T2->getAs<MemberPointerType>();
3121  if (T1MPType && T2MPType &&
3122      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
3123                             QualType(T2MPType->getClass(), 0))) {
3124    T1 = T1MPType->getPointeeType();
3125    T2 = T2MPType->getPointeeType();
3126    return true;
3127  }
3128
3129  if (getLangOptions().ObjC1) {
3130    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
3131                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
3132    if (T1OPType && T2OPType) {
3133      T1 = T1OPType->getPointeeType();
3134      T2 = T2OPType->getPointeeType();
3135      return true;
3136    }
3137  }
3138
3139  // FIXME: Block pointers, too?
3140
3141  return false;
3142}
3143
3144DeclarationNameInfo
3145ASTContext::getNameForTemplate(TemplateName Name,
3146                               SourceLocation NameLoc) const {
3147  switch (Name.getKind()) {
3148  case TemplateName::QualifiedTemplate:
3149  case TemplateName::Template:
3150    // DNInfo work in progress: CHECKME: what about DNLoc?
3151    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
3152                               NameLoc);
3153
3154  case TemplateName::OverloadedTemplate: {
3155    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
3156    // DNInfo work in progress: CHECKME: what about DNLoc?
3157    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
3158  }
3159
3160  case TemplateName::DependentTemplate: {
3161    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3162    DeclarationName DName;
3163    if (DTN->isIdentifier()) {
3164      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
3165      return DeclarationNameInfo(DName, NameLoc);
3166    } else {
3167      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
3168      // DNInfo work in progress: FIXME: source locations?
3169      DeclarationNameLoc DNLoc;
3170      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
3171      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
3172      return DeclarationNameInfo(DName, NameLoc, DNLoc);
3173    }
3174  }
3175
3176  case TemplateName::SubstTemplateTemplateParm: {
3177    SubstTemplateTemplateParmStorage *subst
3178      = Name.getAsSubstTemplateTemplateParm();
3179    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
3180                               NameLoc);
3181  }
3182
3183  case TemplateName::SubstTemplateTemplateParmPack: {
3184    SubstTemplateTemplateParmPackStorage *subst
3185      = Name.getAsSubstTemplateTemplateParmPack();
3186    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
3187                               NameLoc);
3188  }
3189  }
3190
3191  llvm_unreachable("bad template name kind!");
3192}
3193
3194TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
3195  switch (Name.getKind()) {
3196  case TemplateName::QualifiedTemplate:
3197  case TemplateName::Template: {
3198    TemplateDecl *Template = Name.getAsTemplateDecl();
3199    if (TemplateTemplateParmDecl *TTP
3200          = dyn_cast<TemplateTemplateParmDecl>(Template))
3201      Template = getCanonicalTemplateTemplateParmDecl(TTP);
3202
3203    // The canonical template name is the canonical template declaration.
3204    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
3205  }
3206
3207  case TemplateName::OverloadedTemplate:
3208    llvm_unreachable("cannot canonicalize overloaded template");
3209
3210  case TemplateName::DependentTemplate: {
3211    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3212    assert(DTN && "Non-dependent template names must refer to template decls.");
3213    return DTN->CanonicalTemplateName;
3214  }
3215
3216  case TemplateName::SubstTemplateTemplateParm: {
3217    SubstTemplateTemplateParmStorage *subst
3218      = Name.getAsSubstTemplateTemplateParm();
3219    return getCanonicalTemplateName(subst->getReplacement());
3220  }
3221
3222  case TemplateName::SubstTemplateTemplateParmPack: {
3223    SubstTemplateTemplateParmPackStorage *subst
3224                                  = Name.getAsSubstTemplateTemplateParmPack();
3225    TemplateTemplateParmDecl *canonParameter
3226      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
3227    TemplateArgument canonArgPack
3228      = getCanonicalTemplateArgument(subst->getArgumentPack());
3229    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
3230  }
3231  }
3232
3233  llvm_unreachable("bad template name!");
3234}
3235
3236bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
3237  X = getCanonicalTemplateName(X);
3238  Y = getCanonicalTemplateName(Y);
3239  return X.getAsVoidPointer() == Y.getAsVoidPointer();
3240}
3241
3242TemplateArgument
3243ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
3244  switch (Arg.getKind()) {
3245    case TemplateArgument::Null:
3246      return Arg;
3247
3248    case TemplateArgument::Expression:
3249      return Arg;
3250
3251    case TemplateArgument::Declaration:
3252      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
3253
3254    case TemplateArgument::Template:
3255      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
3256
3257    case TemplateArgument::TemplateExpansion:
3258      return TemplateArgument(getCanonicalTemplateName(
3259                                         Arg.getAsTemplateOrTemplatePattern()),
3260                              Arg.getNumTemplateExpansions());
3261
3262    case TemplateArgument::Integral:
3263      return TemplateArgument(*Arg.getAsIntegral(),
3264                              getCanonicalType(Arg.getIntegralType()));
3265
3266    case TemplateArgument::Type:
3267      return TemplateArgument(getCanonicalType(Arg.getAsType()));
3268
3269    case TemplateArgument::Pack: {
3270      if (Arg.pack_size() == 0)
3271        return Arg;
3272
3273      TemplateArgument *CanonArgs
3274        = new (*this) TemplateArgument[Arg.pack_size()];
3275      unsigned Idx = 0;
3276      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
3277                                        AEnd = Arg.pack_end();
3278           A != AEnd; (void)++A, ++Idx)
3279        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
3280
3281      return TemplateArgument(CanonArgs, Arg.pack_size());
3282    }
3283  }
3284
3285  // Silence GCC warning
3286  llvm_unreachable("Unhandled template argument kind");
3287}
3288
3289NestedNameSpecifier *
3290ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
3291  if (!NNS)
3292    return 0;
3293
3294  switch (NNS->getKind()) {
3295  case NestedNameSpecifier::Identifier:
3296    // Canonicalize the prefix but keep the identifier the same.
3297    return NestedNameSpecifier::Create(*this,
3298                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
3299                                       NNS->getAsIdentifier());
3300
3301  case NestedNameSpecifier::Namespace:
3302    // A namespace is canonical; build a nested-name-specifier with
3303    // this namespace and no prefix.
3304    return NestedNameSpecifier::Create(*this, 0,
3305                                 NNS->getAsNamespace()->getOriginalNamespace());
3306
3307  case NestedNameSpecifier::NamespaceAlias:
3308    // A namespace is canonical; build a nested-name-specifier with
3309    // this namespace and no prefix.
3310    return NestedNameSpecifier::Create(*this, 0,
3311                                    NNS->getAsNamespaceAlias()->getNamespace()
3312                                                      ->getOriginalNamespace());
3313
3314  case NestedNameSpecifier::TypeSpec:
3315  case NestedNameSpecifier::TypeSpecWithTemplate: {
3316    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
3317
3318    // If we have some kind of dependent-named type (e.g., "typename T::type"),
3319    // break it apart into its prefix and identifier, then reconsititute those
3320    // as the canonical nested-name-specifier. This is required to canonicalize
3321    // a dependent nested-name-specifier involving typedefs of dependent-name
3322    // types, e.g.,
3323    //   typedef typename T::type T1;
3324    //   typedef typename T1::type T2;
3325    if (const DependentNameType *DNT = T->getAs<DependentNameType>()) {
3326      NestedNameSpecifier *Prefix
3327        = getCanonicalNestedNameSpecifier(DNT->getQualifier());
3328      return NestedNameSpecifier::Create(*this, Prefix,
3329                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
3330    }
3331
3332    // Do the same thing as above, but with dependent-named specializations.
3333    if (const DependentTemplateSpecializationType *DTST
3334          = T->getAs<DependentTemplateSpecializationType>()) {
3335      NestedNameSpecifier *Prefix
3336        = getCanonicalNestedNameSpecifier(DTST->getQualifier());
3337
3338      T = getDependentTemplateSpecializationType(DTST->getKeyword(),
3339                                                 Prefix, DTST->getIdentifier(),
3340                                                 DTST->getNumArgs(),
3341                                                 DTST->getArgs());
3342      T = getCanonicalType(T);
3343    }
3344
3345    return NestedNameSpecifier::Create(*this, 0, false,
3346                                       const_cast<Type*>(T.getTypePtr()));
3347  }
3348
3349  case NestedNameSpecifier::Global:
3350    // The global specifier is canonical and unique.
3351    return NNS;
3352  }
3353
3354  // Required to silence a GCC warning
3355  return 0;
3356}
3357
3358
3359const ArrayType *ASTContext::getAsArrayType(QualType T) const {
3360  // Handle the non-qualified case efficiently.
3361  if (!T.hasLocalQualifiers()) {
3362    // Handle the common positive case fast.
3363    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
3364      return AT;
3365  }
3366
3367  // Handle the common negative case fast.
3368  if (!isa<ArrayType>(T.getCanonicalType()))
3369    return 0;
3370
3371  // Apply any qualifiers from the array type to the element type.  This
3372  // implements C99 6.7.3p8: "If the specification of an array type includes
3373  // any type qualifiers, the element type is so qualified, not the array type."
3374
3375  // If we get here, we either have type qualifiers on the type, or we have
3376  // sugar such as a typedef in the way.  If we have type qualifiers on the type
3377  // we must propagate them down into the element type.
3378
3379  SplitQualType split = T.getSplitDesugaredType();
3380  Qualifiers qs = split.second;
3381
3382  // If we have a simple case, just return now.
3383  const ArrayType *ATy = dyn_cast<ArrayType>(split.first);
3384  if (ATy == 0 || qs.empty())
3385    return ATy;
3386
3387  // Otherwise, we have an array and we have qualifiers on it.  Push the
3388  // qualifiers into the array element type and return a new array type.
3389  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
3390
3391  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
3392    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
3393                                                CAT->getSizeModifier(),
3394                                           CAT->getIndexTypeCVRQualifiers()));
3395  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
3396    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
3397                                                  IAT->getSizeModifier(),
3398                                           IAT->getIndexTypeCVRQualifiers()));
3399
3400  if (const DependentSizedArrayType *DSAT
3401        = dyn_cast<DependentSizedArrayType>(ATy))
3402    return cast<ArrayType>(
3403                     getDependentSizedArrayType(NewEltTy,
3404                                                DSAT->getSizeExpr(),
3405                                                DSAT->getSizeModifier(),
3406                                              DSAT->getIndexTypeCVRQualifiers(),
3407                                                DSAT->getBracketsRange()));
3408
3409  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
3410  return cast<ArrayType>(getVariableArrayType(NewEltTy,
3411                                              VAT->getSizeExpr(),
3412                                              VAT->getSizeModifier(),
3413                                              VAT->getIndexTypeCVRQualifiers(),
3414                                              VAT->getBracketsRange()));
3415}
3416
3417QualType ASTContext::getAdjustedParameterType(QualType T) {
3418  // C99 6.7.5.3p7:
3419  //   A declaration of a parameter as "array of type" shall be
3420  //   adjusted to "qualified pointer to type", where the type
3421  //   qualifiers (if any) are those specified within the [ and ] of
3422  //   the array type derivation.
3423  if (T->isArrayType())
3424    return getArrayDecayedType(T);
3425
3426  // C99 6.7.5.3p8:
3427  //   A declaration of a parameter as "function returning type"
3428  //   shall be adjusted to "pointer to function returning type", as
3429  //   in 6.3.2.1.
3430  if (T->isFunctionType())
3431    return getPointerType(T);
3432
3433  return T;
3434}
3435
3436QualType ASTContext::getSignatureParameterType(QualType T) {
3437  T = getVariableArrayDecayedType(T);
3438  T = getAdjustedParameterType(T);
3439  return T.getUnqualifiedType();
3440}
3441
3442/// getArrayDecayedType - Return the properly qualified result of decaying the
3443/// specified array type to a pointer.  This operation is non-trivial when
3444/// handling typedefs etc.  The canonical type of "T" must be an array type,
3445/// this returns a pointer to a properly qualified element of the array.
3446///
3447/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
3448QualType ASTContext::getArrayDecayedType(QualType Ty) const {
3449  // Get the element type with 'getAsArrayType' so that we don't lose any
3450  // typedefs in the element type of the array.  This also handles propagation
3451  // of type qualifiers from the array type into the element type if present
3452  // (C99 6.7.3p8).
3453  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
3454  assert(PrettyArrayType && "Not an array type!");
3455
3456  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
3457
3458  // int x[restrict 4] ->  int *restrict
3459  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
3460}
3461
3462QualType ASTContext::getBaseElementType(const ArrayType *array) const {
3463  return getBaseElementType(array->getElementType());
3464}
3465
3466QualType ASTContext::getBaseElementType(QualType type) const {
3467  Qualifiers qs;
3468  while (true) {
3469    SplitQualType split = type.getSplitDesugaredType();
3470    const ArrayType *array = split.first->getAsArrayTypeUnsafe();
3471    if (!array) break;
3472
3473    type = array->getElementType();
3474    qs.addConsistentQualifiers(split.second);
3475  }
3476
3477  return getQualifiedType(type, qs);
3478}
3479
3480/// getConstantArrayElementCount - Returns number of constant array elements.
3481uint64_t
3482ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
3483  uint64_t ElementCount = 1;
3484  do {
3485    ElementCount *= CA->getSize().getZExtValue();
3486    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
3487  } while (CA);
3488  return ElementCount;
3489}
3490
3491/// getFloatingRank - Return a relative rank for floating point types.
3492/// This routine will assert if passed a built-in type that isn't a float.
3493static FloatingRank getFloatingRank(QualType T) {
3494  if (const ComplexType *CT = T->getAs<ComplexType>())
3495    return getFloatingRank(CT->getElementType());
3496
3497  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
3498  switch (T->getAs<BuiltinType>()->getKind()) {
3499  default: llvm_unreachable("getFloatingRank(): not a floating type");
3500  case BuiltinType::Half:       return HalfRank;
3501  case BuiltinType::Float:      return FloatRank;
3502  case BuiltinType::Double:     return DoubleRank;
3503  case BuiltinType::LongDouble: return LongDoubleRank;
3504  }
3505}
3506
3507/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
3508/// point or a complex type (based on typeDomain/typeSize).
3509/// 'typeDomain' is a real floating point or complex type.
3510/// 'typeSize' is a real floating point or complex type.
3511QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
3512                                                       QualType Domain) const {
3513  FloatingRank EltRank = getFloatingRank(Size);
3514  if (Domain->isComplexType()) {
3515    switch (EltRank) {
3516    default: llvm_unreachable("getFloatingRank(): illegal value for rank");
3517    case FloatRank:      return FloatComplexTy;
3518    case DoubleRank:     return DoubleComplexTy;
3519    case LongDoubleRank: return LongDoubleComplexTy;
3520    }
3521  }
3522
3523  assert(Domain->isRealFloatingType() && "Unknown domain!");
3524  switch (EltRank) {
3525  default: llvm_unreachable("getFloatingRank(): illegal value for rank");
3526  case FloatRank:      return FloatTy;
3527  case DoubleRank:     return DoubleTy;
3528  case LongDoubleRank: return LongDoubleTy;
3529  }
3530}
3531
3532/// getFloatingTypeOrder - Compare the rank of the two specified floating
3533/// point types, ignoring the domain of the type (i.e. 'double' ==
3534/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3535/// LHS < RHS, return -1.
3536int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
3537  FloatingRank LHSR = getFloatingRank(LHS);
3538  FloatingRank RHSR = getFloatingRank(RHS);
3539
3540  if (LHSR == RHSR)
3541    return 0;
3542  if (LHSR > RHSR)
3543    return 1;
3544  return -1;
3545}
3546
3547/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
3548/// routine will assert if passed a built-in type that isn't an integer or enum,
3549/// or if it is not canonicalized.
3550unsigned ASTContext::getIntegerRank(const Type *T) const {
3551  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
3552  if (const EnumType* ET = dyn_cast<EnumType>(T))
3553    T = ET->getDecl()->getPromotionType().getTypePtr();
3554
3555  if (T->isSpecificBuiltinType(BuiltinType::WChar_S) ||
3556      T->isSpecificBuiltinType(BuiltinType::WChar_U))
3557    T = getFromTargetType(Target->getWCharType()).getTypePtr();
3558
3559  if (T->isSpecificBuiltinType(BuiltinType::Char16))
3560    T = getFromTargetType(Target->getChar16Type()).getTypePtr();
3561
3562  if (T->isSpecificBuiltinType(BuiltinType::Char32))
3563    T = getFromTargetType(Target->getChar32Type()).getTypePtr();
3564
3565  switch (cast<BuiltinType>(T)->getKind()) {
3566  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
3567  case BuiltinType::Bool:
3568    return 1 + (getIntWidth(BoolTy) << 3);
3569  case BuiltinType::Char_S:
3570  case BuiltinType::Char_U:
3571  case BuiltinType::SChar:
3572  case BuiltinType::UChar:
3573    return 2 + (getIntWidth(CharTy) << 3);
3574  case BuiltinType::Short:
3575  case BuiltinType::UShort:
3576    return 3 + (getIntWidth(ShortTy) << 3);
3577  case BuiltinType::Int:
3578  case BuiltinType::UInt:
3579    return 4 + (getIntWidth(IntTy) << 3);
3580  case BuiltinType::Long:
3581  case BuiltinType::ULong:
3582    return 5 + (getIntWidth(LongTy) << 3);
3583  case BuiltinType::LongLong:
3584  case BuiltinType::ULongLong:
3585    return 6 + (getIntWidth(LongLongTy) << 3);
3586  case BuiltinType::Int128:
3587  case BuiltinType::UInt128:
3588    return 7 + (getIntWidth(Int128Ty) << 3);
3589  }
3590}
3591
3592/// \brief Whether this is a promotable bitfield reference according
3593/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
3594///
3595/// \returns the type this bit-field will promote to, or NULL if no
3596/// promotion occurs.
3597QualType ASTContext::isPromotableBitField(Expr *E) const {
3598  if (E->isTypeDependent() || E->isValueDependent())
3599    return QualType();
3600
3601  FieldDecl *Field = E->getBitField();
3602  if (!Field)
3603    return QualType();
3604
3605  QualType FT = Field->getType();
3606
3607  uint64_t BitWidth = Field->getBitWidthValue(*this);
3608  uint64_t IntSize = getTypeSize(IntTy);
3609  // GCC extension compatibility: if the bit-field size is less than or equal
3610  // to the size of int, it gets promoted no matter what its type is.
3611  // For instance, unsigned long bf : 4 gets promoted to signed int.
3612  if (BitWidth < IntSize)
3613    return IntTy;
3614
3615  if (BitWidth == IntSize)
3616    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
3617
3618  // Types bigger than int are not subject to promotions, and therefore act
3619  // like the base type.
3620  // FIXME: This doesn't quite match what gcc does, but what gcc does here
3621  // is ridiculous.
3622  return QualType();
3623}
3624
3625/// getPromotedIntegerType - Returns the type that Promotable will
3626/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
3627/// integer type.
3628QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
3629  assert(!Promotable.isNull());
3630  assert(Promotable->isPromotableIntegerType());
3631  if (const EnumType *ET = Promotable->getAs<EnumType>())
3632    return ET->getDecl()->getPromotionType();
3633  if (Promotable->isSignedIntegerType())
3634    return IntTy;
3635  uint64_t PromotableSize = getTypeSize(Promotable);
3636  uint64_t IntSize = getTypeSize(IntTy);
3637  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3638  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3639}
3640
3641/// \brief Recurses in pointer/array types until it finds an objc retainable
3642/// type and returns its ownership.
3643Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
3644  while (!T.isNull()) {
3645    if (T.getObjCLifetime() != Qualifiers::OCL_None)
3646      return T.getObjCLifetime();
3647    if (T->isArrayType())
3648      T = getBaseElementType(T);
3649    else if (const PointerType *PT = T->getAs<PointerType>())
3650      T = PT->getPointeeType();
3651    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3652      T = RT->getPointeeType();
3653    else
3654      break;
3655  }
3656
3657  return Qualifiers::OCL_None;
3658}
3659
3660/// getIntegerTypeOrder - Returns the highest ranked integer type:
3661/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3662/// LHS < RHS, return -1.
3663int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
3664  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
3665  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
3666  if (LHSC == RHSC) return 0;
3667
3668  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3669  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3670
3671  unsigned LHSRank = getIntegerRank(LHSC);
3672  unsigned RHSRank = getIntegerRank(RHSC);
3673
3674  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3675    if (LHSRank == RHSRank) return 0;
3676    return LHSRank > RHSRank ? 1 : -1;
3677  }
3678
3679  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3680  if (LHSUnsigned) {
3681    // If the unsigned [LHS] type is larger, return it.
3682    if (LHSRank >= RHSRank)
3683      return 1;
3684
3685    // If the signed type can represent all values of the unsigned type, it
3686    // wins.  Because we are dealing with 2's complement and types that are
3687    // powers of two larger than each other, this is always safe.
3688    return -1;
3689  }
3690
3691  // If the unsigned [RHS] type is larger, return it.
3692  if (RHSRank >= LHSRank)
3693    return -1;
3694
3695  // If the signed type can represent all values of the unsigned type, it
3696  // wins.  Because we are dealing with 2's complement and types that are
3697  // powers of two larger than each other, this is always safe.
3698  return 1;
3699}
3700
3701static RecordDecl *
3702CreateRecordDecl(const ASTContext &Ctx, RecordDecl::TagKind TK,
3703                 DeclContext *DC, IdentifierInfo *Id) {
3704  SourceLocation Loc;
3705  if (Ctx.getLangOptions().CPlusPlus)
3706    return CXXRecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3707  else
3708    return RecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3709}
3710
3711// getCFConstantStringType - Return the type used for constant CFStrings.
3712QualType ASTContext::getCFConstantStringType() const {
3713  if (!CFConstantStringTypeDecl) {
3714    CFConstantStringTypeDecl =
3715      CreateRecordDecl(*this, TTK_Struct, TUDecl,
3716                       &Idents.get("NSConstantString"));
3717    CFConstantStringTypeDecl->startDefinition();
3718
3719    QualType FieldTypes[4];
3720
3721    // const int *isa;
3722    FieldTypes[0] = getPointerType(IntTy.withConst());
3723    // int flags;
3724    FieldTypes[1] = IntTy;
3725    // const char *str;
3726    FieldTypes[2] = getPointerType(CharTy.withConst());
3727    // long length;
3728    FieldTypes[3] = LongTy;
3729
3730    // Create fields
3731    for (unsigned i = 0; i < 4; ++i) {
3732      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3733                                           SourceLocation(),
3734                                           SourceLocation(), 0,
3735                                           FieldTypes[i], /*TInfo=*/0,
3736                                           /*BitWidth=*/0,
3737                                           /*Mutable=*/false,
3738                                           /*HasInit=*/false);
3739      Field->setAccess(AS_public);
3740      CFConstantStringTypeDecl->addDecl(Field);
3741    }
3742
3743    CFConstantStringTypeDecl->completeDefinition();
3744  }
3745
3746  return getTagDeclType(CFConstantStringTypeDecl);
3747}
3748
3749void ASTContext::setCFConstantStringType(QualType T) {
3750  const RecordType *Rec = T->getAs<RecordType>();
3751  assert(Rec && "Invalid CFConstantStringType");
3752  CFConstantStringTypeDecl = Rec->getDecl();
3753}
3754
3755QualType ASTContext::getBlockDescriptorType() const {
3756  if (BlockDescriptorType)
3757    return getTagDeclType(BlockDescriptorType);
3758
3759  RecordDecl *T;
3760  // FIXME: Needs the FlagAppleBlock bit.
3761  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3762                       &Idents.get("__block_descriptor"));
3763  T->startDefinition();
3764
3765  QualType FieldTypes[] = {
3766    UnsignedLongTy,
3767    UnsignedLongTy,
3768  };
3769
3770  const char *FieldNames[] = {
3771    "reserved",
3772    "Size"
3773  };
3774
3775  for (size_t i = 0; i < 2; ++i) {
3776    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3777                                         SourceLocation(),
3778                                         &Idents.get(FieldNames[i]),
3779                                         FieldTypes[i], /*TInfo=*/0,
3780                                         /*BitWidth=*/0,
3781                                         /*Mutable=*/false,
3782                                         /*HasInit=*/false);
3783    Field->setAccess(AS_public);
3784    T->addDecl(Field);
3785  }
3786
3787  T->completeDefinition();
3788
3789  BlockDescriptorType = T;
3790
3791  return getTagDeclType(BlockDescriptorType);
3792}
3793
3794QualType ASTContext::getBlockDescriptorExtendedType() const {
3795  if (BlockDescriptorExtendedType)
3796    return getTagDeclType(BlockDescriptorExtendedType);
3797
3798  RecordDecl *T;
3799  // FIXME: Needs the FlagAppleBlock bit.
3800  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3801                       &Idents.get("__block_descriptor_withcopydispose"));
3802  T->startDefinition();
3803
3804  QualType FieldTypes[] = {
3805    UnsignedLongTy,
3806    UnsignedLongTy,
3807    getPointerType(VoidPtrTy),
3808    getPointerType(VoidPtrTy)
3809  };
3810
3811  const char *FieldNames[] = {
3812    "reserved",
3813    "Size",
3814    "CopyFuncPtr",
3815    "DestroyFuncPtr"
3816  };
3817
3818  for (size_t i = 0; i < 4; ++i) {
3819    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3820                                         SourceLocation(),
3821                                         &Idents.get(FieldNames[i]),
3822                                         FieldTypes[i], /*TInfo=*/0,
3823                                         /*BitWidth=*/0,
3824                                         /*Mutable=*/false,
3825                                         /*HasInit=*/false);
3826    Field->setAccess(AS_public);
3827    T->addDecl(Field);
3828  }
3829
3830  T->completeDefinition();
3831
3832  BlockDescriptorExtendedType = T;
3833
3834  return getTagDeclType(BlockDescriptorExtendedType);
3835}
3836
3837bool ASTContext::BlockRequiresCopying(QualType Ty) const {
3838  if (Ty->isObjCRetainableType())
3839    return true;
3840  if (getLangOptions().CPlusPlus) {
3841    if (const RecordType *RT = Ty->getAs<RecordType>()) {
3842      CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
3843      return RD->hasConstCopyConstructor();
3844
3845    }
3846  }
3847  return false;
3848}
3849
3850QualType
3851ASTContext::BuildByRefType(StringRef DeclName, QualType Ty) const {
3852  //  type = struct __Block_byref_1_X {
3853  //    void *__isa;
3854  //    struct __Block_byref_1_X *__forwarding;
3855  //    unsigned int __flags;
3856  //    unsigned int __size;
3857  //    void *__copy_helper;            // as needed
3858  //    void *__destroy_help            // as needed
3859  //    int X;
3860  //  } *
3861
3862  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3863
3864  // FIXME: Move up
3865  llvm::SmallString<36> Name;
3866  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3867                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3868  RecordDecl *T;
3869  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, &Idents.get(Name.str()));
3870  T->startDefinition();
3871  QualType Int32Ty = IntTy;
3872  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3873  QualType FieldTypes[] = {
3874    getPointerType(VoidPtrTy),
3875    getPointerType(getTagDeclType(T)),
3876    Int32Ty,
3877    Int32Ty,
3878    getPointerType(VoidPtrTy),
3879    getPointerType(VoidPtrTy),
3880    Ty
3881  };
3882
3883  StringRef FieldNames[] = {
3884    "__isa",
3885    "__forwarding",
3886    "__flags",
3887    "__size",
3888    "__copy_helper",
3889    "__destroy_helper",
3890    DeclName,
3891  };
3892
3893  for (size_t i = 0; i < 7; ++i) {
3894    if (!HasCopyAndDispose && i >=4 && i <= 5)
3895      continue;
3896    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3897                                         SourceLocation(),
3898                                         &Idents.get(FieldNames[i]),
3899                                         FieldTypes[i], /*TInfo=*/0,
3900                                         /*BitWidth=*/0, /*Mutable=*/false,
3901                                         /*HasInit=*/false);
3902    Field->setAccess(AS_public);
3903    T->addDecl(Field);
3904  }
3905
3906  T->completeDefinition();
3907
3908  return getPointerType(getTagDeclType(T));
3909}
3910
3911TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
3912  if (!ObjCInstanceTypeDecl)
3913    ObjCInstanceTypeDecl = TypedefDecl::Create(*this,
3914                                               getTranslationUnitDecl(),
3915                                               SourceLocation(),
3916                                               SourceLocation(),
3917                                               &Idents.get("instancetype"),
3918                                     getTrivialTypeSourceInfo(getObjCIdType()));
3919  return ObjCInstanceTypeDecl;
3920}
3921
3922// This returns true if a type has been typedefed to BOOL:
3923// typedef <type> BOOL;
3924static bool isTypeTypedefedAsBOOL(QualType T) {
3925  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3926    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3927      return II->isStr("BOOL");
3928
3929  return false;
3930}
3931
3932/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3933/// purpose.
3934CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
3935  if (!type->isIncompleteArrayType() && type->isIncompleteType())
3936    return CharUnits::Zero();
3937
3938  CharUnits sz = getTypeSizeInChars(type);
3939
3940  // Make all integer and enum types at least as large as an int
3941  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3942    sz = std::max(sz, getTypeSizeInChars(IntTy));
3943  // Treat arrays as pointers, since that's how they're passed in.
3944  else if (type->isArrayType())
3945    sz = getTypeSizeInChars(VoidPtrTy);
3946  return sz;
3947}
3948
3949static inline
3950std::string charUnitsToString(const CharUnits &CU) {
3951  return llvm::itostr(CU.getQuantity());
3952}
3953
3954/// getObjCEncodingForBlock - Return the encoded type for this block
3955/// declaration.
3956std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
3957  std::string S;
3958
3959  const BlockDecl *Decl = Expr->getBlockDecl();
3960  QualType BlockTy =
3961      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3962  // Encode result type.
3963  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3964  // Compute size of all parameters.
3965  // Start with computing size of a pointer in number of bytes.
3966  // FIXME: There might(should) be a better way of doing this computation!
3967  SourceLocation Loc;
3968  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3969  CharUnits ParmOffset = PtrSize;
3970  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3971       E = Decl->param_end(); PI != E; ++PI) {
3972    QualType PType = (*PI)->getType();
3973    CharUnits sz = getObjCEncodingTypeSize(PType);
3974    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3975    ParmOffset += sz;
3976  }
3977  // Size of the argument frame
3978  S += charUnitsToString(ParmOffset);
3979  // Block pointer and offset.
3980  S += "@?0";
3981
3982  // Argument types.
3983  ParmOffset = PtrSize;
3984  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3985       Decl->param_end(); PI != E; ++PI) {
3986    ParmVarDecl *PVDecl = *PI;
3987    QualType PType = PVDecl->getOriginalType();
3988    if (const ArrayType *AT =
3989          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3990      // Use array's original type only if it has known number of
3991      // elements.
3992      if (!isa<ConstantArrayType>(AT))
3993        PType = PVDecl->getType();
3994    } else if (PType->isFunctionType())
3995      PType = PVDecl->getType();
3996    getObjCEncodingForType(PType, S);
3997    S += charUnitsToString(ParmOffset);
3998    ParmOffset += getObjCEncodingTypeSize(PType);
3999  }
4000
4001  return S;
4002}
4003
4004bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
4005                                                std::string& S) {
4006  // Encode result type.
4007  getObjCEncodingForType(Decl->getResultType(), S);
4008  CharUnits ParmOffset;
4009  // Compute size of all parameters.
4010  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4011       E = Decl->param_end(); PI != E; ++PI) {
4012    QualType PType = (*PI)->getType();
4013    CharUnits sz = getObjCEncodingTypeSize(PType);
4014    if (sz.isZero())
4015      return true;
4016
4017    assert (sz.isPositive() &&
4018        "getObjCEncodingForFunctionDecl - Incomplete param type");
4019    ParmOffset += sz;
4020  }
4021  S += charUnitsToString(ParmOffset);
4022  ParmOffset = CharUnits::Zero();
4023
4024  // Argument types.
4025  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4026       E = Decl->param_end(); PI != E; ++PI) {
4027    ParmVarDecl *PVDecl = *PI;
4028    QualType PType = PVDecl->getOriginalType();
4029    if (const ArrayType *AT =
4030          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4031      // Use array's original type only if it has known number of
4032      // elements.
4033      if (!isa<ConstantArrayType>(AT))
4034        PType = PVDecl->getType();
4035    } else if (PType->isFunctionType())
4036      PType = PVDecl->getType();
4037    getObjCEncodingForType(PType, S);
4038    S += charUnitsToString(ParmOffset);
4039    ParmOffset += getObjCEncodingTypeSize(PType);
4040  }
4041
4042  return false;
4043}
4044
4045/// getObjCEncodingForMethodDecl - Return the encoded type for this method
4046/// declaration.
4047bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
4048                                              std::string& S) const {
4049  // FIXME: This is not very efficient.
4050  // Encode type qualifer, 'in', 'inout', etc. for the return type.
4051  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
4052  // Encode result type.
4053  getObjCEncodingForType(Decl->getResultType(), S);
4054  // Compute size of all parameters.
4055  // Start with computing size of a pointer in number of bytes.
4056  // FIXME: There might(should) be a better way of doing this computation!
4057  SourceLocation Loc;
4058  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4059  // The first two arguments (self and _cmd) are pointers; account for
4060  // their size.
4061  CharUnits ParmOffset = 2 * PtrSize;
4062  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4063       E = Decl->sel_param_end(); PI != E; ++PI) {
4064    QualType PType = (*PI)->getType();
4065    CharUnits sz = getObjCEncodingTypeSize(PType);
4066    if (sz.isZero())
4067      return true;
4068
4069    assert (sz.isPositive() &&
4070        "getObjCEncodingForMethodDecl - Incomplete param type");
4071    ParmOffset += sz;
4072  }
4073  S += charUnitsToString(ParmOffset);
4074  S += "@0:";
4075  S += charUnitsToString(PtrSize);
4076
4077  // Argument types.
4078  ParmOffset = 2 * PtrSize;
4079  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4080       E = Decl->sel_param_end(); PI != E; ++PI) {
4081    const ParmVarDecl *PVDecl = *PI;
4082    QualType PType = PVDecl->getOriginalType();
4083    if (const ArrayType *AT =
4084          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4085      // Use array's original type only if it has known number of
4086      // elements.
4087      if (!isa<ConstantArrayType>(AT))
4088        PType = PVDecl->getType();
4089    } else if (PType->isFunctionType())
4090      PType = PVDecl->getType();
4091    // Process argument qualifiers for user supplied arguments; such as,
4092    // 'in', 'inout', etc.
4093    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
4094    getObjCEncodingForType(PType, S);
4095    S += charUnitsToString(ParmOffset);
4096    ParmOffset += getObjCEncodingTypeSize(PType);
4097  }
4098
4099  return false;
4100}
4101
4102/// getObjCEncodingForPropertyDecl - Return the encoded type for this
4103/// property declaration. If non-NULL, Container must be either an
4104/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
4105/// NULL when getting encodings for protocol properties.
4106/// Property attributes are stored as a comma-delimited C string. The simple
4107/// attributes readonly and bycopy are encoded as single characters. The
4108/// parametrized attributes, getter=name, setter=name, and ivar=name, are
4109/// encoded as single characters, followed by an identifier. Property types
4110/// are also encoded as a parametrized attribute. The characters used to encode
4111/// these attributes are defined by the following enumeration:
4112/// @code
4113/// enum PropertyAttributes {
4114/// kPropertyReadOnly = 'R',   // property is read-only.
4115/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
4116/// kPropertyByref = '&',  // property is a reference to the value last assigned
4117/// kPropertyDynamic = 'D',    // property is dynamic
4118/// kPropertyGetter = 'G',     // followed by getter selector name
4119/// kPropertySetter = 'S',     // followed by setter selector name
4120/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
4121/// kPropertyType = 't'              // followed by old-style type encoding.
4122/// kPropertyWeak = 'W'              // 'weak' property
4123/// kPropertyStrong = 'P'            // property GC'able
4124/// kPropertyNonAtomic = 'N'         // property non-atomic
4125/// };
4126/// @endcode
4127void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
4128                                                const Decl *Container,
4129                                                std::string& S) const {
4130  // Collect information from the property implementation decl(s).
4131  bool Dynamic = false;
4132  ObjCPropertyImplDecl *SynthesizePID = 0;
4133
4134  // FIXME: Duplicated code due to poor abstraction.
4135  if (Container) {
4136    if (const ObjCCategoryImplDecl *CID =
4137        dyn_cast<ObjCCategoryImplDecl>(Container)) {
4138      for (ObjCCategoryImplDecl::propimpl_iterator
4139             i = CID->propimpl_begin(), e = CID->propimpl_end();
4140           i != e; ++i) {
4141        ObjCPropertyImplDecl *PID = *i;
4142        if (PID->getPropertyDecl() == PD) {
4143          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4144            Dynamic = true;
4145          } else {
4146            SynthesizePID = PID;
4147          }
4148        }
4149      }
4150    } else {
4151      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
4152      for (ObjCCategoryImplDecl::propimpl_iterator
4153             i = OID->propimpl_begin(), e = OID->propimpl_end();
4154           i != e; ++i) {
4155        ObjCPropertyImplDecl *PID = *i;
4156        if (PID->getPropertyDecl() == PD) {
4157          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4158            Dynamic = true;
4159          } else {
4160            SynthesizePID = PID;
4161          }
4162        }
4163      }
4164    }
4165  }
4166
4167  // FIXME: This is not very efficient.
4168  S = "T";
4169
4170  // Encode result type.
4171  // GCC has some special rules regarding encoding of properties which
4172  // closely resembles encoding of ivars.
4173  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
4174                             true /* outermost type */,
4175                             true /* encoding for property */);
4176
4177  if (PD->isReadOnly()) {
4178    S += ",R";
4179  } else {
4180    switch (PD->getSetterKind()) {
4181    case ObjCPropertyDecl::Assign: break;
4182    case ObjCPropertyDecl::Copy:   S += ",C"; break;
4183    case ObjCPropertyDecl::Retain: S += ",&"; break;
4184    case ObjCPropertyDecl::Weak:   S += ",W"; break;
4185    }
4186  }
4187
4188  // It really isn't clear at all what this means, since properties
4189  // are "dynamic by default".
4190  if (Dynamic)
4191    S += ",D";
4192
4193  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
4194    S += ",N";
4195
4196  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
4197    S += ",G";
4198    S += PD->getGetterName().getAsString();
4199  }
4200
4201  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
4202    S += ",S";
4203    S += PD->getSetterName().getAsString();
4204  }
4205
4206  if (SynthesizePID) {
4207    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
4208    S += ",V";
4209    S += OID->getNameAsString();
4210  }
4211
4212  // FIXME: OBJCGC: weak & strong
4213}
4214
4215/// getLegacyIntegralTypeEncoding -
4216/// Another legacy compatibility encoding: 32-bit longs are encoded as
4217/// 'l' or 'L' , but not always.  For typedefs, we need to use
4218/// 'i' or 'I' instead if encoding a struct field, or a pointer!
4219///
4220void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
4221  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
4222    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
4223      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
4224        PointeeTy = UnsignedIntTy;
4225      else
4226        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
4227          PointeeTy = IntTy;
4228    }
4229  }
4230}
4231
4232void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
4233                                        const FieldDecl *Field) const {
4234  // We follow the behavior of gcc, expanding structures which are
4235  // directly pointed to, and expanding embedded structures. Note that
4236  // these rules are sufficient to prevent recursive encoding of the
4237  // same type.
4238  getObjCEncodingForTypeImpl(T, S, true, true, Field,
4239                             true /* outermost type */);
4240}
4241
4242static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
4243    switch (T->getAs<BuiltinType>()->getKind()) {
4244    default: llvm_unreachable("Unhandled builtin type kind");
4245    case BuiltinType::Void:       return 'v';
4246    case BuiltinType::Bool:       return 'B';
4247    case BuiltinType::Char_U:
4248    case BuiltinType::UChar:      return 'C';
4249    case BuiltinType::UShort:     return 'S';
4250    case BuiltinType::UInt:       return 'I';
4251    case BuiltinType::ULong:
4252        return C->getIntWidth(T) == 32 ? 'L' : 'Q';
4253    case BuiltinType::UInt128:    return 'T';
4254    case BuiltinType::ULongLong:  return 'Q';
4255    case BuiltinType::Char_S:
4256    case BuiltinType::SChar:      return 'c';
4257    case BuiltinType::Short:      return 's';
4258    case BuiltinType::WChar_S:
4259    case BuiltinType::WChar_U:
4260    case BuiltinType::Int:        return 'i';
4261    case BuiltinType::Long:
4262      return C->getIntWidth(T) == 32 ? 'l' : 'q';
4263    case BuiltinType::LongLong:   return 'q';
4264    case BuiltinType::Int128:     return 't';
4265    case BuiltinType::Float:      return 'f';
4266    case BuiltinType::Double:     return 'd';
4267    case BuiltinType::LongDouble: return 'D';
4268    }
4269}
4270
4271static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
4272  EnumDecl *Enum = ET->getDecl();
4273
4274  // The encoding of an non-fixed enum type is always 'i', regardless of size.
4275  if (!Enum->isFixed())
4276    return 'i';
4277
4278  // The encoding of a fixed enum type matches its fixed underlying type.
4279  return ObjCEncodingForPrimitiveKind(C, Enum->getIntegerType());
4280}
4281
4282static void EncodeBitField(const ASTContext *Ctx, std::string& S,
4283                           QualType T, const FieldDecl *FD) {
4284  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
4285  S += 'b';
4286  // The NeXT runtime encodes bit fields as b followed by the number of bits.
4287  // The GNU runtime requires more information; bitfields are encoded as b,
4288  // then the offset (in bits) of the first element, then the type of the
4289  // bitfield, then the size in bits.  For example, in this structure:
4290  //
4291  // struct
4292  // {
4293  //    int integer;
4294  //    int flags:2;
4295  // };
4296  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
4297  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
4298  // information is not especially sensible, but we're stuck with it for
4299  // compatibility with GCC, although providing it breaks anything that
4300  // actually uses runtime introspection and wants to work on both runtimes...
4301  if (!Ctx->getLangOptions().NeXTRuntime) {
4302    const RecordDecl *RD = FD->getParent();
4303    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
4304    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
4305    if (const EnumType *ET = T->getAs<EnumType>())
4306      S += ObjCEncodingForEnumType(Ctx, ET);
4307    else
4308      S += ObjCEncodingForPrimitiveKind(Ctx, T);
4309  }
4310  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
4311}
4312
4313// FIXME: Use SmallString for accumulating string.
4314void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
4315                                            bool ExpandPointedToStructures,
4316                                            bool ExpandStructures,
4317                                            const FieldDecl *FD,
4318                                            bool OutermostType,
4319                                            bool EncodingProperty,
4320                                            bool StructField) const {
4321  if (T->getAs<BuiltinType>()) {
4322    if (FD && FD->isBitField())
4323      return EncodeBitField(this, S, T, FD);
4324    S += ObjCEncodingForPrimitiveKind(this, T);
4325    return;
4326  }
4327
4328  if (const ComplexType *CT = T->getAs<ComplexType>()) {
4329    S += 'j';
4330    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
4331                               false);
4332    return;
4333  }
4334
4335  // encoding for pointer or r3eference types.
4336  QualType PointeeTy;
4337  if (const PointerType *PT = T->getAs<PointerType>()) {
4338    if (PT->isObjCSelType()) {
4339      S += ':';
4340      return;
4341    }
4342    PointeeTy = PT->getPointeeType();
4343  }
4344  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4345    PointeeTy = RT->getPointeeType();
4346  if (!PointeeTy.isNull()) {
4347    bool isReadOnly = false;
4348    // For historical/compatibility reasons, the read-only qualifier of the
4349    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
4350    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
4351    // Also, do not emit the 'r' for anything but the outermost type!
4352    if (isa<TypedefType>(T.getTypePtr())) {
4353      if (OutermostType && T.isConstQualified()) {
4354        isReadOnly = true;
4355        S += 'r';
4356      }
4357    } else if (OutermostType) {
4358      QualType P = PointeeTy;
4359      while (P->getAs<PointerType>())
4360        P = P->getAs<PointerType>()->getPointeeType();
4361      if (P.isConstQualified()) {
4362        isReadOnly = true;
4363        S += 'r';
4364      }
4365    }
4366    if (isReadOnly) {
4367      // Another legacy compatibility encoding. Some ObjC qualifier and type
4368      // combinations need to be rearranged.
4369      // Rewrite "in const" from "nr" to "rn"
4370      if (StringRef(S).endswith("nr"))
4371        S.replace(S.end()-2, S.end(), "rn");
4372    }
4373
4374    if (PointeeTy->isCharType()) {
4375      // char pointer types should be encoded as '*' unless it is a
4376      // type that has been typedef'd to 'BOOL'.
4377      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
4378        S += '*';
4379        return;
4380      }
4381    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
4382      // GCC binary compat: Need to convert "struct objc_class *" to "#".
4383      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
4384        S += '#';
4385        return;
4386      }
4387      // GCC binary compat: Need to convert "struct objc_object *" to "@".
4388      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
4389        S += '@';
4390        return;
4391      }
4392      // fall through...
4393    }
4394    S += '^';
4395    getLegacyIntegralTypeEncoding(PointeeTy);
4396
4397    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
4398                               NULL);
4399    return;
4400  }
4401
4402  if (const ArrayType *AT =
4403      // Ignore type qualifiers etc.
4404        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
4405    if (isa<IncompleteArrayType>(AT) && !StructField) {
4406      // Incomplete arrays are encoded as a pointer to the array element.
4407      S += '^';
4408
4409      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4410                                 false, ExpandStructures, FD);
4411    } else {
4412      S += '[';
4413
4414      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
4415        if (getTypeSize(CAT->getElementType()) == 0)
4416          S += '0';
4417        else
4418          S += llvm::utostr(CAT->getSize().getZExtValue());
4419      } else {
4420        //Variable length arrays are encoded as a regular array with 0 elements.
4421        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
4422               "Unknown array type!");
4423        S += '0';
4424      }
4425
4426      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4427                                 false, ExpandStructures, FD);
4428      S += ']';
4429    }
4430    return;
4431  }
4432
4433  if (T->getAs<FunctionType>()) {
4434    S += '?';
4435    return;
4436  }
4437
4438  if (const RecordType *RTy = T->getAs<RecordType>()) {
4439    RecordDecl *RDecl = RTy->getDecl();
4440    S += RDecl->isUnion() ? '(' : '{';
4441    // Anonymous structures print as '?'
4442    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
4443      S += II->getName();
4444      if (ClassTemplateSpecializationDecl *Spec
4445          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
4446        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
4447        std::string TemplateArgsStr
4448          = TemplateSpecializationType::PrintTemplateArgumentList(
4449                                            TemplateArgs.data(),
4450                                            TemplateArgs.size(),
4451                                            (*this).getPrintingPolicy());
4452
4453        S += TemplateArgsStr;
4454      }
4455    } else {
4456      S += '?';
4457    }
4458    if (ExpandStructures) {
4459      S += '=';
4460      if (!RDecl->isUnion()) {
4461        getObjCEncodingForStructureImpl(RDecl, S, FD);
4462      } else {
4463        for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4464                                     FieldEnd = RDecl->field_end();
4465             Field != FieldEnd; ++Field) {
4466          if (FD) {
4467            S += '"';
4468            S += Field->getNameAsString();
4469            S += '"';
4470          }
4471
4472          // Special case bit-fields.
4473          if (Field->isBitField()) {
4474            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
4475                                       (*Field));
4476          } else {
4477            QualType qt = Field->getType();
4478            getLegacyIntegralTypeEncoding(qt);
4479            getObjCEncodingForTypeImpl(qt, S, false, true,
4480                                       FD, /*OutermostType*/false,
4481                                       /*EncodingProperty*/false,
4482                                       /*StructField*/true);
4483          }
4484        }
4485      }
4486    }
4487    S += RDecl->isUnion() ? ')' : '}';
4488    return;
4489  }
4490
4491  if (const EnumType *ET = T->getAs<EnumType>()) {
4492    if (FD && FD->isBitField())
4493      EncodeBitField(this, S, T, FD);
4494    else
4495      S += ObjCEncodingForEnumType(this, ET);
4496    return;
4497  }
4498
4499  if (T->isBlockPointerType()) {
4500    S += "@?"; // Unlike a pointer-to-function, which is "^?".
4501    return;
4502  }
4503
4504  // Ignore protocol qualifiers when mangling at this level.
4505  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
4506    T = OT->getBaseType();
4507
4508  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
4509    // @encode(class_name)
4510    ObjCInterfaceDecl *OI = OIT->getDecl();
4511    S += '{';
4512    const IdentifierInfo *II = OI->getIdentifier();
4513    S += II->getName();
4514    S += '=';
4515    SmallVector<const ObjCIvarDecl*, 32> Ivars;
4516    DeepCollectObjCIvars(OI, true, Ivars);
4517    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
4518      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
4519      if (Field->isBitField())
4520        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
4521      else
4522        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
4523    }
4524    S += '}';
4525    return;
4526  }
4527
4528  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
4529    if (OPT->isObjCIdType()) {
4530      S += '@';
4531      return;
4532    }
4533
4534    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
4535      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
4536      // Since this is a binary compatibility issue, need to consult with runtime
4537      // folks. Fortunately, this is a *very* obsure construct.
4538      S += '#';
4539      return;
4540    }
4541
4542    if (OPT->isObjCQualifiedIdType()) {
4543      getObjCEncodingForTypeImpl(getObjCIdType(), S,
4544                                 ExpandPointedToStructures,
4545                                 ExpandStructures, FD);
4546      if (FD || EncodingProperty) {
4547        // Note that we do extended encoding of protocol qualifer list
4548        // Only when doing ivar or property encoding.
4549        S += '"';
4550        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4551             E = OPT->qual_end(); I != E; ++I) {
4552          S += '<';
4553          S += (*I)->getNameAsString();
4554          S += '>';
4555        }
4556        S += '"';
4557      }
4558      return;
4559    }
4560
4561    QualType PointeeTy = OPT->getPointeeType();
4562    if (!EncodingProperty &&
4563        isa<TypedefType>(PointeeTy.getTypePtr())) {
4564      // Another historical/compatibility reason.
4565      // We encode the underlying type which comes out as
4566      // {...};
4567      S += '^';
4568      getObjCEncodingForTypeImpl(PointeeTy, S,
4569                                 false, ExpandPointedToStructures,
4570                                 NULL);
4571      return;
4572    }
4573
4574    S += '@';
4575    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
4576      S += '"';
4577      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4578      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4579           E = OPT->qual_end(); I != E; ++I) {
4580        S += '<';
4581        S += (*I)->getNameAsString();
4582        S += '>';
4583      }
4584      S += '"';
4585    }
4586    return;
4587  }
4588
4589  // gcc just blithely ignores member pointers.
4590  // TODO: maybe there should be a mangling for these
4591  if (T->getAs<MemberPointerType>())
4592    return;
4593
4594  if (T->isVectorType()) {
4595    // This matches gcc's encoding, even though technically it is
4596    // insufficient.
4597    // FIXME. We should do a better job than gcc.
4598    return;
4599  }
4600
4601  llvm_unreachable("@encode for type not implemented!");
4602}
4603
4604void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
4605                                                 std::string &S,
4606                                                 const FieldDecl *FD,
4607                                                 bool includeVBases) const {
4608  assert(RDecl && "Expected non-null RecordDecl");
4609  assert(!RDecl->isUnion() && "Should not be called for unions");
4610  if (!RDecl->getDefinition())
4611    return;
4612
4613  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
4614  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
4615  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
4616
4617  if (CXXRec) {
4618    for (CXXRecordDecl::base_class_iterator
4619           BI = CXXRec->bases_begin(),
4620           BE = CXXRec->bases_end(); BI != BE; ++BI) {
4621      if (!BI->isVirtual()) {
4622        CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4623        if (base->isEmpty())
4624          continue;
4625        uint64_t offs = layout.getBaseClassOffsetInBits(base);
4626        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4627                                  std::make_pair(offs, base));
4628      }
4629    }
4630  }
4631
4632  unsigned i = 0;
4633  for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4634                               FieldEnd = RDecl->field_end();
4635       Field != FieldEnd; ++Field, ++i) {
4636    uint64_t offs = layout.getFieldOffset(i);
4637    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4638                              std::make_pair(offs, *Field));
4639  }
4640
4641  if (CXXRec && includeVBases) {
4642    for (CXXRecordDecl::base_class_iterator
4643           BI = CXXRec->vbases_begin(),
4644           BE = CXXRec->vbases_end(); BI != BE; ++BI) {
4645      CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4646      if (base->isEmpty())
4647        continue;
4648      uint64_t offs = layout.getVBaseClassOffsetInBits(base);
4649      if (FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
4650        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
4651                                  std::make_pair(offs, base));
4652    }
4653  }
4654
4655  CharUnits size;
4656  if (CXXRec) {
4657    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
4658  } else {
4659    size = layout.getSize();
4660  }
4661
4662  uint64_t CurOffs = 0;
4663  std::multimap<uint64_t, NamedDecl *>::iterator
4664    CurLayObj = FieldOrBaseOffsets.begin();
4665
4666  if ((CurLayObj != FieldOrBaseOffsets.end() && CurLayObj->first != 0) ||
4667      (CurLayObj == FieldOrBaseOffsets.end() &&
4668         CXXRec && CXXRec->isDynamicClass())) {
4669    assert(CXXRec && CXXRec->isDynamicClass() &&
4670           "Offset 0 was empty but no VTable ?");
4671    if (FD) {
4672      S += "\"_vptr$";
4673      std::string recname = CXXRec->getNameAsString();
4674      if (recname.empty()) recname = "?";
4675      S += recname;
4676      S += '"';
4677    }
4678    S += "^^?";
4679    CurOffs += getTypeSize(VoidPtrTy);
4680  }
4681
4682  if (!RDecl->hasFlexibleArrayMember()) {
4683    // Mark the end of the structure.
4684    uint64_t offs = toBits(size);
4685    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4686                              std::make_pair(offs, (NamedDecl*)0));
4687  }
4688
4689  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
4690    assert(CurOffs <= CurLayObj->first);
4691
4692    if (CurOffs < CurLayObj->first) {
4693      uint64_t padding = CurLayObj->first - CurOffs;
4694      // FIXME: There doesn't seem to be a way to indicate in the encoding that
4695      // packing/alignment of members is different that normal, in which case
4696      // the encoding will be out-of-sync with the real layout.
4697      // If the runtime switches to just consider the size of types without
4698      // taking into account alignment, we could make padding explicit in the
4699      // encoding (e.g. using arrays of chars). The encoding strings would be
4700      // longer then though.
4701      CurOffs += padding;
4702    }
4703
4704    NamedDecl *dcl = CurLayObj->second;
4705    if (dcl == 0)
4706      break; // reached end of structure.
4707
4708    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
4709      // We expand the bases without their virtual bases since those are going
4710      // in the initial structure. Note that this differs from gcc which
4711      // expands virtual bases each time one is encountered in the hierarchy,
4712      // making the encoding type bigger than it really is.
4713      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false);
4714      assert(!base->isEmpty());
4715      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
4716    } else {
4717      FieldDecl *field = cast<FieldDecl>(dcl);
4718      if (FD) {
4719        S += '"';
4720        S += field->getNameAsString();
4721        S += '"';
4722      }
4723
4724      if (field->isBitField()) {
4725        EncodeBitField(this, S, field->getType(), field);
4726        CurOffs += field->getBitWidthValue(*this);
4727      } else {
4728        QualType qt = field->getType();
4729        getLegacyIntegralTypeEncoding(qt);
4730        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
4731                                   /*OutermostType*/false,
4732                                   /*EncodingProperty*/false,
4733                                   /*StructField*/true);
4734        CurOffs += getTypeSize(field->getType());
4735      }
4736    }
4737  }
4738}
4739
4740void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4741                                                 std::string& S) const {
4742  if (QT & Decl::OBJC_TQ_In)
4743    S += 'n';
4744  if (QT & Decl::OBJC_TQ_Inout)
4745    S += 'N';
4746  if (QT & Decl::OBJC_TQ_Out)
4747    S += 'o';
4748  if (QT & Decl::OBJC_TQ_Bycopy)
4749    S += 'O';
4750  if (QT & Decl::OBJC_TQ_Byref)
4751    S += 'R';
4752  if (QT & Decl::OBJC_TQ_Oneway)
4753    S += 'V';
4754}
4755
4756void ASTContext::setBuiltinVaListType(QualType T) {
4757  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4758
4759  BuiltinVaListType = T;
4760}
4761
4762TypedefDecl *ASTContext::getObjCIdDecl() const {
4763  if (!ObjCIdDecl) {
4764    QualType T = getObjCObjectType(ObjCBuiltinIdTy, 0, 0);
4765    T = getObjCObjectPointerType(T);
4766    TypeSourceInfo *IdInfo = getTrivialTypeSourceInfo(T);
4767    ObjCIdDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4768                                     getTranslationUnitDecl(),
4769                                     SourceLocation(), SourceLocation(),
4770                                     &Idents.get("id"), IdInfo);
4771  }
4772
4773  return ObjCIdDecl;
4774}
4775
4776TypedefDecl *ASTContext::getObjCSelDecl() const {
4777  if (!ObjCSelDecl) {
4778    QualType SelT = getPointerType(ObjCBuiltinSelTy);
4779    TypeSourceInfo *SelInfo = getTrivialTypeSourceInfo(SelT);
4780    ObjCSelDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4781                                      getTranslationUnitDecl(),
4782                                      SourceLocation(), SourceLocation(),
4783                                      &Idents.get("SEL"), SelInfo);
4784  }
4785  return ObjCSelDecl;
4786}
4787
4788void ASTContext::setObjCProtoType(QualType QT) {
4789  ObjCProtoType = QT;
4790}
4791
4792TypedefDecl *ASTContext::getObjCClassDecl() const {
4793  if (!ObjCClassDecl) {
4794    QualType T = getObjCObjectType(ObjCBuiltinClassTy, 0, 0);
4795    T = getObjCObjectPointerType(T);
4796    TypeSourceInfo *ClassInfo = getTrivialTypeSourceInfo(T);
4797    ObjCClassDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4798                                        getTranslationUnitDecl(),
4799                                        SourceLocation(), SourceLocation(),
4800                                        &Idents.get("Class"), ClassInfo);
4801  }
4802
4803  return ObjCClassDecl;
4804}
4805
4806void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4807  assert(ObjCConstantStringType.isNull() &&
4808         "'NSConstantString' type already set!");
4809
4810  ObjCConstantStringType = getObjCInterfaceType(Decl);
4811}
4812
4813/// \brief Retrieve the template name that corresponds to a non-empty
4814/// lookup.
4815TemplateName
4816ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4817                                      UnresolvedSetIterator End) const {
4818  unsigned size = End - Begin;
4819  assert(size > 1 && "set is not overloaded!");
4820
4821  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4822                          size * sizeof(FunctionTemplateDecl*));
4823  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4824
4825  NamedDecl **Storage = OT->getStorage();
4826  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4827    NamedDecl *D = *I;
4828    assert(isa<FunctionTemplateDecl>(D) ||
4829           (isa<UsingShadowDecl>(D) &&
4830            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4831    *Storage++ = D;
4832  }
4833
4834  return TemplateName(OT);
4835}
4836
4837/// \brief Retrieve the template name that represents a qualified
4838/// template name such as \c std::vector.
4839TemplateName
4840ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4841                                     bool TemplateKeyword,
4842                                     TemplateDecl *Template) const {
4843  assert(NNS && "Missing nested-name-specifier in qualified template name");
4844
4845  // FIXME: Canonicalization?
4846  llvm::FoldingSetNodeID ID;
4847  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4848
4849  void *InsertPos = 0;
4850  QualifiedTemplateName *QTN =
4851    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4852  if (!QTN) {
4853    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4854    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4855  }
4856
4857  return TemplateName(QTN);
4858}
4859
4860/// \brief Retrieve the template name that represents a dependent
4861/// template name such as \c MetaFun::template apply.
4862TemplateName
4863ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4864                                     const IdentifierInfo *Name) const {
4865  assert((!NNS || NNS->isDependent()) &&
4866         "Nested name specifier must be dependent");
4867
4868  llvm::FoldingSetNodeID ID;
4869  DependentTemplateName::Profile(ID, NNS, Name);
4870
4871  void *InsertPos = 0;
4872  DependentTemplateName *QTN =
4873    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4874
4875  if (QTN)
4876    return TemplateName(QTN);
4877
4878  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4879  if (CanonNNS == NNS) {
4880    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4881  } else {
4882    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4883    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4884    DependentTemplateName *CheckQTN =
4885      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4886    assert(!CheckQTN && "Dependent type name canonicalization broken");
4887    (void)CheckQTN;
4888  }
4889
4890  DependentTemplateNames.InsertNode(QTN, InsertPos);
4891  return TemplateName(QTN);
4892}
4893
4894/// \brief Retrieve the template name that represents a dependent
4895/// template name such as \c MetaFun::template operator+.
4896TemplateName
4897ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4898                                     OverloadedOperatorKind Operator) const {
4899  assert((!NNS || NNS->isDependent()) &&
4900         "Nested name specifier must be dependent");
4901
4902  llvm::FoldingSetNodeID ID;
4903  DependentTemplateName::Profile(ID, NNS, Operator);
4904
4905  void *InsertPos = 0;
4906  DependentTemplateName *QTN
4907    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4908
4909  if (QTN)
4910    return TemplateName(QTN);
4911
4912  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4913  if (CanonNNS == NNS) {
4914    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4915  } else {
4916    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4917    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4918
4919    DependentTemplateName *CheckQTN
4920      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4921    assert(!CheckQTN && "Dependent template name canonicalization broken");
4922    (void)CheckQTN;
4923  }
4924
4925  DependentTemplateNames.InsertNode(QTN, InsertPos);
4926  return TemplateName(QTN);
4927}
4928
4929TemplateName
4930ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
4931                                         TemplateName replacement) const {
4932  llvm::FoldingSetNodeID ID;
4933  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
4934
4935  void *insertPos = 0;
4936  SubstTemplateTemplateParmStorage *subst
4937    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
4938
4939  if (!subst) {
4940    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
4941    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
4942  }
4943
4944  return TemplateName(subst);
4945}
4946
4947TemplateName
4948ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
4949                                       const TemplateArgument &ArgPack) const {
4950  ASTContext &Self = const_cast<ASTContext &>(*this);
4951  llvm::FoldingSetNodeID ID;
4952  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
4953
4954  void *InsertPos = 0;
4955  SubstTemplateTemplateParmPackStorage *Subst
4956    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
4957
4958  if (!Subst) {
4959    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
4960                                                           ArgPack.pack_size(),
4961                                                         ArgPack.pack_begin());
4962    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
4963  }
4964
4965  return TemplateName(Subst);
4966}
4967
4968/// getFromTargetType - Given one of the integer types provided by
4969/// TargetInfo, produce the corresponding type. The unsigned @p Type
4970/// is actually a value of type @c TargetInfo::IntType.
4971CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4972  switch (Type) {
4973  case TargetInfo::NoInt: return CanQualType();
4974  case TargetInfo::SignedShort: return ShortTy;
4975  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4976  case TargetInfo::SignedInt: return IntTy;
4977  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4978  case TargetInfo::SignedLong: return LongTy;
4979  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4980  case TargetInfo::SignedLongLong: return LongLongTy;
4981  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4982  }
4983
4984  llvm_unreachable("Unhandled TargetInfo::IntType value");
4985}
4986
4987//===----------------------------------------------------------------------===//
4988//                        Type Predicates.
4989//===----------------------------------------------------------------------===//
4990
4991/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4992/// garbage collection attribute.
4993///
4994Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
4995  if (getLangOptions().getGC() == LangOptions::NonGC)
4996    return Qualifiers::GCNone;
4997
4998  assert(getLangOptions().ObjC1);
4999  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
5000
5001  // Default behaviour under objective-C's gc is for ObjC pointers
5002  // (or pointers to them) be treated as though they were declared
5003  // as __strong.
5004  if (GCAttrs == Qualifiers::GCNone) {
5005    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
5006      return Qualifiers::Strong;
5007    else if (Ty->isPointerType())
5008      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
5009  } else {
5010    // It's not valid to set GC attributes on anything that isn't a
5011    // pointer.
5012#ifndef NDEBUG
5013    QualType CT = Ty->getCanonicalTypeInternal();
5014    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
5015      CT = AT->getElementType();
5016    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
5017#endif
5018  }
5019  return GCAttrs;
5020}
5021
5022//===----------------------------------------------------------------------===//
5023//                        Type Compatibility Testing
5024//===----------------------------------------------------------------------===//
5025
5026/// areCompatVectorTypes - Return true if the two specified vector types are
5027/// compatible.
5028static bool areCompatVectorTypes(const VectorType *LHS,
5029                                 const VectorType *RHS) {
5030  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
5031  return LHS->getElementType() == RHS->getElementType() &&
5032         LHS->getNumElements() == RHS->getNumElements();
5033}
5034
5035bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
5036                                          QualType SecondVec) {
5037  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
5038  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
5039
5040  if (hasSameUnqualifiedType(FirstVec, SecondVec))
5041    return true;
5042
5043  // Treat Neon vector types and most AltiVec vector types as if they are the
5044  // equivalent GCC vector types.
5045  const VectorType *First = FirstVec->getAs<VectorType>();
5046  const VectorType *Second = SecondVec->getAs<VectorType>();
5047  if (First->getNumElements() == Second->getNumElements() &&
5048      hasSameType(First->getElementType(), Second->getElementType()) &&
5049      First->getVectorKind() != VectorType::AltiVecPixel &&
5050      First->getVectorKind() != VectorType::AltiVecBool &&
5051      Second->getVectorKind() != VectorType::AltiVecPixel &&
5052      Second->getVectorKind() != VectorType::AltiVecBool)
5053    return true;
5054
5055  return false;
5056}
5057
5058//===----------------------------------------------------------------------===//
5059// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
5060//===----------------------------------------------------------------------===//
5061
5062/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
5063/// inheritance hierarchy of 'rProto'.
5064bool
5065ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
5066                                           ObjCProtocolDecl *rProto) const {
5067  if (lProto == rProto)
5068    return true;
5069  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
5070       E = rProto->protocol_end(); PI != E; ++PI)
5071    if (ProtocolCompatibleWithProtocol(lProto, *PI))
5072      return true;
5073  return false;
5074}
5075
5076/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
5077/// return true if lhs's protocols conform to rhs's protocol; false
5078/// otherwise.
5079bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
5080  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
5081    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
5082  return false;
5083}
5084
5085/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
5086/// Class<p1, ...>.
5087bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
5088                                                      QualType rhs) {
5089  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
5090  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5091  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
5092
5093  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5094       E = lhsQID->qual_end(); I != E; ++I) {
5095    bool match = false;
5096    ObjCProtocolDecl *lhsProto = *I;
5097    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5098         E = rhsOPT->qual_end(); J != E; ++J) {
5099      ObjCProtocolDecl *rhsProto = *J;
5100      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
5101        match = true;
5102        break;
5103      }
5104    }
5105    if (!match)
5106      return false;
5107  }
5108  return true;
5109}
5110
5111/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
5112/// ObjCQualifiedIDType.
5113bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
5114                                                   bool compare) {
5115  // Allow id<P..> and an 'id' or void* type in all cases.
5116  if (lhs->isVoidPointerType() ||
5117      lhs->isObjCIdType() || lhs->isObjCClassType())
5118    return true;
5119  else if (rhs->isVoidPointerType() ||
5120           rhs->isObjCIdType() || rhs->isObjCClassType())
5121    return true;
5122
5123  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
5124    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5125
5126    if (!rhsOPT) return false;
5127
5128    if (rhsOPT->qual_empty()) {
5129      // If the RHS is a unqualified interface pointer "NSString*",
5130      // make sure we check the class hierarchy.
5131      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5132        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5133             E = lhsQID->qual_end(); I != E; ++I) {
5134          // when comparing an id<P> on lhs with a static type on rhs,
5135          // see if static class implements all of id's protocols, directly or
5136          // through its super class and categories.
5137          if (!rhsID->ClassImplementsProtocol(*I, true))
5138            return false;
5139        }
5140      }
5141      // If there are no qualifiers and no interface, we have an 'id'.
5142      return true;
5143    }
5144    // Both the right and left sides have qualifiers.
5145    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5146         E = lhsQID->qual_end(); I != E; ++I) {
5147      ObjCProtocolDecl *lhsProto = *I;
5148      bool match = false;
5149
5150      // when comparing an id<P> on lhs with a static type on rhs,
5151      // see if static class implements all of id's protocols, directly or
5152      // through its super class and categories.
5153      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5154           E = rhsOPT->qual_end(); J != E; ++J) {
5155        ObjCProtocolDecl *rhsProto = *J;
5156        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5157            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5158          match = true;
5159          break;
5160        }
5161      }
5162      // If the RHS is a qualified interface pointer "NSString<P>*",
5163      // make sure we check the class hierarchy.
5164      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5165        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5166             E = lhsQID->qual_end(); I != E; ++I) {
5167          // when comparing an id<P> on lhs with a static type on rhs,
5168          // see if static class implements all of id's protocols, directly or
5169          // through its super class and categories.
5170          if (rhsID->ClassImplementsProtocol(*I, true)) {
5171            match = true;
5172            break;
5173          }
5174        }
5175      }
5176      if (!match)
5177        return false;
5178    }
5179
5180    return true;
5181  }
5182
5183  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
5184  assert(rhsQID && "One of the LHS/RHS should be id<x>");
5185
5186  if (const ObjCObjectPointerType *lhsOPT =
5187        lhs->getAsObjCInterfacePointerType()) {
5188    // If both the right and left sides have qualifiers.
5189    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
5190         E = lhsOPT->qual_end(); I != E; ++I) {
5191      ObjCProtocolDecl *lhsProto = *I;
5192      bool match = false;
5193
5194      // when comparing an id<P> on rhs with a static type on lhs,
5195      // see if static class implements all of id's protocols, directly or
5196      // through its super class and categories.
5197      // First, lhs protocols in the qualifier list must be found, direct
5198      // or indirect in rhs's qualifier list or it is a mismatch.
5199      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5200           E = rhsQID->qual_end(); J != E; ++J) {
5201        ObjCProtocolDecl *rhsProto = *J;
5202        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5203            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5204          match = true;
5205          break;
5206        }
5207      }
5208      if (!match)
5209        return false;
5210    }
5211
5212    // Static class's protocols, or its super class or category protocols
5213    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
5214    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
5215      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5216      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
5217      // This is rather dubious but matches gcc's behavior. If lhs has
5218      // no type qualifier and its class has no static protocol(s)
5219      // assume that it is mismatch.
5220      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
5221        return false;
5222      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5223           LHSInheritedProtocols.begin(),
5224           E = LHSInheritedProtocols.end(); I != E; ++I) {
5225        bool match = false;
5226        ObjCProtocolDecl *lhsProto = (*I);
5227        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5228             E = rhsQID->qual_end(); J != E; ++J) {
5229          ObjCProtocolDecl *rhsProto = *J;
5230          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5231              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5232            match = true;
5233            break;
5234          }
5235        }
5236        if (!match)
5237          return false;
5238      }
5239    }
5240    return true;
5241  }
5242  return false;
5243}
5244
5245/// canAssignObjCInterfaces - Return true if the two interface types are
5246/// compatible for assignment from RHS to LHS.  This handles validation of any
5247/// protocol qualifiers on the LHS or RHS.
5248///
5249bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
5250                                         const ObjCObjectPointerType *RHSOPT) {
5251  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5252  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5253
5254  // If either type represents the built-in 'id' or 'Class' types, return true.
5255  if (LHS->isObjCUnqualifiedIdOrClass() ||
5256      RHS->isObjCUnqualifiedIdOrClass())
5257    return true;
5258
5259  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
5260    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5261                                             QualType(RHSOPT,0),
5262                                             false);
5263
5264  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
5265    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
5266                                                QualType(RHSOPT,0));
5267
5268  // If we have 2 user-defined types, fall into that path.
5269  if (LHS->getInterface() && RHS->getInterface())
5270    return canAssignObjCInterfaces(LHS, RHS);
5271
5272  return false;
5273}
5274
5275/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
5276/// for providing type-safety for objective-c pointers used to pass/return
5277/// arguments in block literals. When passed as arguments, passing 'A*' where
5278/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
5279/// not OK. For the return type, the opposite is not OK.
5280bool ASTContext::canAssignObjCInterfacesInBlockPointer(
5281                                         const ObjCObjectPointerType *LHSOPT,
5282                                         const ObjCObjectPointerType *RHSOPT,
5283                                         bool BlockReturnType) {
5284  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
5285    return true;
5286
5287  if (LHSOPT->isObjCBuiltinType()) {
5288    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
5289  }
5290
5291  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
5292    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5293                                             QualType(RHSOPT,0),
5294                                             false);
5295
5296  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
5297  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
5298  if (LHS && RHS)  { // We have 2 user-defined types.
5299    if (LHS != RHS) {
5300      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
5301        return BlockReturnType;
5302      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
5303        return !BlockReturnType;
5304    }
5305    else
5306      return true;
5307  }
5308  return false;
5309}
5310
5311/// getIntersectionOfProtocols - This routine finds the intersection of set
5312/// of protocols inherited from two distinct objective-c pointer objects.
5313/// It is used to build composite qualifier list of the composite type of
5314/// the conditional expression involving two objective-c pointer objects.
5315static
5316void getIntersectionOfProtocols(ASTContext &Context,
5317                                const ObjCObjectPointerType *LHSOPT,
5318                                const ObjCObjectPointerType *RHSOPT,
5319      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
5320
5321  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5322  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5323  assert(LHS->getInterface() && "LHS must have an interface base");
5324  assert(RHS->getInterface() && "RHS must have an interface base");
5325
5326  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
5327  unsigned LHSNumProtocols = LHS->getNumProtocols();
5328  if (LHSNumProtocols > 0)
5329    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
5330  else {
5331    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5332    Context.CollectInheritedProtocols(LHS->getInterface(),
5333                                      LHSInheritedProtocols);
5334    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
5335                                LHSInheritedProtocols.end());
5336  }
5337
5338  unsigned RHSNumProtocols = RHS->getNumProtocols();
5339  if (RHSNumProtocols > 0) {
5340    ObjCProtocolDecl **RHSProtocols =
5341      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
5342    for (unsigned i = 0; i < RHSNumProtocols; ++i)
5343      if (InheritedProtocolSet.count(RHSProtocols[i]))
5344        IntersectionOfProtocols.push_back(RHSProtocols[i]);
5345  } else {
5346    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
5347    Context.CollectInheritedProtocols(RHS->getInterface(),
5348                                      RHSInheritedProtocols);
5349    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5350         RHSInheritedProtocols.begin(),
5351         E = RHSInheritedProtocols.end(); I != E; ++I)
5352      if (InheritedProtocolSet.count((*I)))
5353        IntersectionOfProtocols.push_back((*I));
5354  }
5355}
5356
5357/// areCommonBaseCompatible - Returns common base class of the two classes if
5358/// one found. Note that this is O'2 algorithm. But it will be called as the
5359/// last type comparison in a ?-exp of ObjC pointer types before a
5360/// warning is issued. So, its invokation is extremely rare.
5361QualType ASTContext::areCommonBaseCompatible(
5362                                          const ObjCObjectPointerType *Lptr,
5363                                          const ObjCObjectPointerType *Rptr) {
5364  const ObjCObjectType *LHS = Lptr->getObjectType();
5365  const ObjCObjectType *RHS = Rptr->getObjectType();
5366  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
5367  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
5368  if (!LDecl || !RDecl || (LDecl == RDecl))
5369    return QualType();
5370
5371  do {
5372    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
5373    if (canAssignObjCInterfaces(LHS, RHS)) {
5374      SmallVector<ObjCProtocolDecl *, 8> Protocols;
5375      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
5376
5377      QualType Result = QualType(LHS, 0);
5378      if (!Protocols.empty())
5379        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
5380      Result = getObjCObjectPointerType(Result);
5381      return Result;
5382    }
5383  } while ((LDecl = LDecl->getSuperClass()));
5384
5385  return QualType();
5386}
5387
5388bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
5389                                         const ObjCObjectType *RHS) {
5390  assert(LHS->getInterface() && "LHS is not an interface type");
5391  assert(RHS->getInterface() && "RHS is not an interface type");
5392
5393  // Verify that the base decls are compatible: the RHS must be a subclass of
5394  // the LHS.
5395  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
5396    return false;
5397
5398  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
5399  // protocol qualified at all, then we are good.
5400  if (LHS->getNumProtocols() == 0)
5401    return true;
5402
5403  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't,
5404  // more detailed analysis is required.
5405  if (RHS->getNumProtocols() == 0) {
5406    // OK, if LHS is a superclass of RHS *and*
5407    // this superclass is assignment compatible with LHS.
5408    // false otherwise.
5409    bool IsSuperClass =
5410      LHS->getInterface()->isSuperClassOf(RHS->getInterface());
5411    if (IsSuperClass) {
5412      // OK if conversion of LHS to SuperClass results in narrowing of types
5413      // ; i.e., SuperClass may implement at least one of the protocols
5414      // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
5415      // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
5416      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
5417      CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
5418      // If super class has no protocols, it is not a match.
5419      if (SuperClassInheritedProtocols.empty())
5420        return false;
5421
5422      for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5423           LHSPE = LHS->qual_end();
5424           LHSPI != LHSPE; LHSPI++) {
5425        bool SuperImplementsProtocol = false;
5426        ObjCProtocolDecl *LHSProto = (*LHSPI);
5427
5428        for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5429             SuperClassInheritedProtocols.begin(),
5430             E = SuperClassInheritedProtocols.end(); I != E; ++I) {
5431          ObjCProtocolDecl *SuperClassProto = (*I);
5432          if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
5433            SuperImplementsProtocol = true;
5434            break;
5435          }
5436        }
5437        if (!SuperImplementsProtocol)
5438          return false;
5439      }
5440      return true;
5441    }
5442    return false;
5443  }
5444
5445  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5446                                     LHSPE = LHS->qual_end();
5447       LHSPI != LHSPE; LHSPI++) {
5448    bool RHSImplementsProtocol = false;
5449
5450    // If the RHS doesn't implement the protocol on the left, the types
5451    // are incompatible.
5452    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
5453                                       RHSPE = RHS->qual_end();
5454         RHSPI != RHSPE; RHSPI++) {
5455      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
5456        RHSImplementsProtocol = true;
5457        break;
5458      }
5459    }
5460    // FIXME: For better diagnostics, consider passing back the protocol name.
5461    if (!RHSImplementsProtocol)
5462      return false;
5463  }
5464  // The RHS implements all protocols listed on the LHS.
5465  return true;
5466}
5467
5468bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
5469  // get the "pointed to" types
5470  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
5471  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
5472
5473  if (!LHSOPT || !RHSOPT)
5474    return false;
5475
5476  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
5477         canAssignObjCInterfaces(RHSOPT, LHSOPT);
5478}
5479
5480bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
5481  return canAssignObjCInterfaces(
5482                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
5483                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
5484}
5485
5486/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
5487/// both shall have the identically qualified version of a compatible type.
5488/// C99 6.2.7p1: Two types have compatible types if their types are the
5489/// same. See 6.7.[2,3,5] for additional rules.
5490bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
5491                                    bool CompareUnqualified) {
5492  if (getLangOptions().CPlusPlus)
5493    return hasSameType(LHS, RHS);
5494
5495  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
5496}
5497
5498bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
5499  return typesAreCompatible(LHS, RHS);
5500}
5501
5502bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
5503  return !mergeTypes(LHS, RHS, true).isNull();
5504}
5505
5506/// mergeTransparentUnionType - if T is a transparent union type and a member
5507/// of T is compatible with SubType, return the merged type, else return
5508/// QualType()
5509QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
5510                                               bool OfBlockPointer,
5511                                               bool Unqualified) {
5512  if (const RecordType *UT = T->getAsUnionType()) {
5513    RecordDecl *UD = UT->getDecl();
5514    if (UD->hasAttr<TransparentUnionAttr>()) {
5515      for (RecordDecl::field_iterator it = UD->field_begin(),
5516           itend = UD->field_end(); it != itend; ++it) {
5517        QualType ET = it->getType().getUnqualifiedType();
5518        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
5519        if (!MT.isNull())
5520          return MT;
5521      }
5522    }
5523  }
5524
5525  return QualType();
5526}
5527
5528/// mergeFunctionArgumentTypes - merge two types which appear as function
5529/// argument types
5530QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
5531                                                bool OfBlockPointer,
5532                                                bool Unqualified) {
5533  // GNU extension: two types are compatible if they appear as a function
5534  // argument, one of the types is a transparent union type and the other
5535  // type is compatible with a union member
5536  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
5537                                              Unqualified);
5538  if (!lmerge.isNull())
5539    return lmerge;
5540
5541  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
5542                                              Unqualified);
5543  if (!rmerge.isNull())
5544    return rmerge;
5545
5546  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
5547}
5548
5549QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
5550                                        bool OfBlockPointer,
5551                                        bool Unqualified) {
5552  const FunctionType *lbase = lhs->getAs<FunctionType>();
5553  const FunctionType *rbase = rhs->getAs<FunctionType>();
5554  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
5555  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
5556  bool allLTypes = true;
5557  bool allRTypes = true;
5558
5559  // Check return type
5560  QualType retType;
5561  if (OfBlockPointer) {
5562    QualType RHS = rbase->getResultType();
5563    QualType LHS = lbase->getResultType();
5564    bool UnqualifiedResult = Unqualified;
5565    if (!UnqualifiedResult)
5566      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
5567    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
5568  }
5569  else
5570    retType = mergeTypes(lbase->getResultType(), rbase->getResultType(), false,
5571                         Unqualified);
5572  if (retType.isNull()) return QualType();
5573
5574  if (Unqualified)
5575    retType = retType.getUnqualifiedType();
5576
5577  CanQualType LRetType = getCanonicalType(lbase->getResultType());
5578  CanQualType RRetType = getCanonicalType(rbase->getResultType());
5579  if (Unqualified) {
5580    LRetType = LRetType.getUnqualifiedType();
5581    RRetType = RRetType.getUnqualifiedType();
5582  }
5583
5584  if (getCanonicalType(retType) != LRetType)
5585    allLTypes = false;
5586  if (getCanonicalType(retType) != RRetType)
5587    allRTypes = false;
5588
5589  // FIXME: double check this
5590  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
5591  //                           rbase->getRegParmAttr() != 0 &&
5592  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
5593  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
5594  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
5595
5596  // Compatible functions must have compatible calling conventions
5597  if (!isSameCallConv(lbaseInfo.getCC(), rbaseInfo.getCC()))
5598    return QualType();
5599
5600  // Regparm is part of the calling convention.
5601  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
5602    return QualType();
5603  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
5604    return QualType();
5605
5606  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
5607    return QualType();
5608
5609  // functypes which return are preferred over those that do not.
5610  if (lbaseInfo.getNoReturn() && !rbaseInfo.getNoReturn())
5611    allLTypes = false;
5612  else if (!lbaseInfo.getNoReturn() && rbaseInfo.getNoReturn())
5613    allRTypes = false;
5614  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
5615  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
5616
5617  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
5618
5619  if (lproto && rproto) { // two C99 style function prototypes
5620    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
5621           "C++ shouldn't be here");
5622    unsigned lproto_nargs = lproto->getNumArgs();
5623    unsigned rproto_nargs = rproto->getNumArgs();
5624
5625    // Compatible functions must have the same number of arguments
5626    if (lproto_nargs != rproto_nargs)
5627      return QualType();
5628
5629    // Variadic and non-variadic functions aren't compatible
5630    if (lproto->isVariadic() != rproto->isVariadic())
5631      return QualType();
5632
5633    if (lproto->getTypeQuals() != rproto->getTypeQuals())
5634      return QualType();
5635
5636    if (LangOpts.ObjCAutoRefCount &&
5637        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
5638      return QualType();
5639
5640    // Check argument compatibility
5641    SmallVector<QualType, 10> types;
5642    for (unsigned i = 0; i < lproto_nargs; i++) {
5643      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
5644      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
5645      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
5646                                                    OfBlockPointer,
5647                                                    Unqualified);
5648      if (argtype.isNull()) return QualType();
5649
5650      if (Unqualified)
5651        argtype = argtype.getUnqualifiedType();
5652
5653      types.push_back(argtype);
5654      if (Unqualified) {
5655        largtype = largtype.getUnqualifiedType();
5656        rargtype = rargtype.getUnqualifiedType();
5657      }
5658
5659      if (getCanonicalType(argtype) != getCanonicalType(largtype))
5660        allLTypes = false;
5661      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
5662        allRTypes = false;
5663    }
5664
5665    if (allLTypes) return lhs;
5666    if (allRTypes) return rhs;
5667
5668    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
5669    EPI.ExtInfo = einfo;
5670    return getFunctionType(retType, types.begin(), types.size(), EPI);
5671  }
5672
5673  if (lproto) allRTypes = false;
5674  if (rproto) allLTypes = false;
5675
5676  const FunctionProtoType *proto = lproto ? lproto : rproto;
5677  if (proto) {
5678    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
5679    if (proto->isVariadic()) return QualType();
5680    // Check that the types are compatible with the types that
5681    // would result from default argument promotions (C99 6.7.5.3p15).
5682    // The only types actually affected are promotable integer
5683    // types and floats, which would be passed as a different
5684    // type depending on whether the prototype is visible.
5685    unsigned proto_nargs = proto->getNumArgs();
5686    for (unsigned i = 0; i < proto_nargs; ++i) {
5687      QualType argTy = proto->getArgType(i);
5688
5689      // Look at the promotion type of enum types, since that is the type used
5690      // to pass enum values.
5691      if (const EnumType *Enum = argTy->getAs<EnumType>())
5692        argTy = Enum->getDecl()->getPromotionType();
5693
5694      if (argTy->isPromotableIntegerType() ||
5695          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
5696        return QualType();
5697    }
5698
5699    if (allLTypes) return lhs;
5700    if (allRTypes) return rhs;
5701
5702    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
5703    EPI.ExtInfo = einfo;
5704    return getFunctionType(retType, proto->arg_type_begin(),
5705                           proto->getNumArgs(), EPI);
5706  }
5707
5708  if (allLTypes) return lhs;
5709  if (allRTypes) return rhs;
5710  return getFunctionNoProtoType(retType, einfo);
5711}
5712
5713QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
5714                                bool OfBlockPointer,
5715                                bool Unqualified, bool BlockReturnType) {
5716  // C++ [expr]: If an expression initially has the type "reference to T", the
5717  // type is adjusted to "T" prior to any further analysis, the expression
5718  // designates the object or function denoted by the reference, and the
5719  // expression is an lvalue unless the reference is an rvalue reference and
5720  // the expression is a function call (possibly inside parentheses).
5721  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
5722  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
5723
5724  if (Unqualified) {
5725    LHS = LHS.getUnqualifiedType();
5726    RHS = RHS.getUnqualifiedType();
5727  }
5728
5729  QualType LHSCan = getCanonicalType(LHS),
5730           RHSCan = getCanonicalType(RHS);
5731
5732  // If two types are identical, they are compatible.
5733  if (LHSCan == RHSCan)
5734    return LHS;
5735
5736  // If the qualifiers are different, the types aren't compatible... mostly.
5737  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5738  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5739  if (LQuals != RQuals) {
5740    // If any of these qualifiers are different, we have a type
5741    // mismatch.
5742    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5743        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
5744        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
5745      return QualType();
5746
5747    // Exactly one GC qualifier difference is allowed: __strong is
5748    // okay if the other type has no GC qualifier but is an Objective
5749    // C object pointer (i.e. implicitly strong by default).  We fix
5750    // this by pretending that the unqualified type was actually
5751    // qualified __strong.
5752    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5753    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5754    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5755
5756    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5757      return QualType();
5758
5759    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
5760      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
5761    }
5762    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
5763      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
5764    }
5765    return QualType();
5766  }
5767
5768  // Okay, qualifiers are equal.
5769
5770  Type::TypeClass LHSClass = LHSCan->getTypeClass();
5771  Type::TypeClass RHSClass = RHSCan->getTypeClass();
5772
5773  // We want to consider the two function types to be the same for these
5774  // comparisons, just force one to the other.
5775  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
5776  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
5777
5778  // Same as above for arrays
5779  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
5780    LHSClass = Type::ConstantArray;
5781  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
5782    RHSClass = Type::ConstantArray;
5783
5784  // ObjCInterfaces are just specialized ObjCObjects.
5785  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
5786  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
5787
5788  // Canonicalize ExtVector -> Vector.
5789  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
5790  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
5791
5792  // If the canonical type classes don't match.
5793  if (LHSClass != RHSClass) {
5794    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
5795    // a signed integer type, or an unsigned integer type.
5796    // Compatibility is based on the underlying type, not the promotion
5797    // type.
5798    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
5799      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
5800        return RHS;
5801    }
5802    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
5803      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
5804        return LHS;
5805    }
5806
5807    return QualType();
5808  }
5809
5810  // The canonical type classes match.
5811  switch (LHSClass) {
5812#define TYPE(Class, Base)
5813#define ABSTRACT_TYPE(Class, Base)
5814#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
5815#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
5816#define DEPENDENT_TYPE(Class, Base) case Type::Class:
5817#include "clang/AST/TypeNodes.def"
5818    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
5819
5820  case Type::LValueReference:
5821  case Type::RValueReference:
5822  case Type::MemberPointer:
5823    llvm_unreachable("C++ should never be in mergeTypes");
5824
5825  case Type::ObjCInterface:
5826  case Type::IncompleteArray:
5827  case Type::VariableArray:
5828  case Type::FunctionProto:
5829  case Type::ExtVector:
5830    llvm_unreachable("Types are eliminated above");
5831
5832  case Type::Pointer:
5833  {
5834    // Merge two pointer types, while trying to preserve typedef info
5835    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
5836    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
5837    if (Unqualified) {
5838      LHSPointee = LHSPointee.getUnqualifiedType();
5839      RHSPointee = RHSPointee.getUnqualifiedType();
5840    }
5841    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
5842                                     Unqualified);
5843    if (ResultType.isNull()) return QualType();
5844    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5845      return LHS;
5846    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5847      return RHS;
5848    return getPointerType(ResultType);
5849  }
5850  case Type::BlockPointer:
5851  {
5852    // Merge two block pointer types, while trying to preserve typedef info
5853    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
5854    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
5855    if (Unqualified) {
5856      LHSPointee = LHSPointee.getUnqualifiedType();
5857      RHSPointee = RHSPointee.getUnqualifiedType();
5858    }
5859    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
5860                                     Unqualified);
5861    if (ResultType.isNull()) return QualType();
5862    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5863      return LHS;
5864    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5865      return RHS;
5866    return getBlockPointerType(ResultType);
5867  }
5868  case Type::Atomic:
5869  {
5870    // Merge two pointer types, while trying to preserve typedef info
5871    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
5872    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
5873    if (Unqualified) {
5874      LHSValue = LHSValue.getUnqualifiedType();
5875      RHSValue = RHSValue.getUnqualifiedType();
5876    }
5877    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
5878                                     Unqualified);
5879    if (ResultType.isNull()) return QualType();
5880    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
5881      return LHS;
5882    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
5883      return RHS;
5884    return getAtomicType(ResultType);
5885  }
5886  case Type::ConstantArray:
5887  {
5888    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
5889    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
5890    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
5891      return QualType();
5892
5893    QualType LHSElem = getAsArrayType(LHS)->getElementType();
5894    QualType RHSElem = getAsArrayType(RHS)->getElementType();
5895    if (Unqualified) {
5896      LHSElem = LHSElem.getUnqualifiedType();
5897      RHSElem = RHSElem.getUnqualifiedType();
5898    }
5899
5900    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
5901    if (ResultType.isNull()) return QualType();
5902    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5903      return LHS;
5904    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5905      return RHS;
5906    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
5907                                          ArrayType::ArraySizeModifier(), 0);
5908    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
5909                                          ArrayType::ArraySizeModifier(), 0);
5910    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
5911    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
5912    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5913      return LHS;
5914    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5915      return RHS;
5916    if (LVAT) {
5917      // FIXME: This isn't correct! But tricky to implement because
5918      // the array's size has to be the size of LHS, but the type
5919      // has to be different.
5920      return LHS;
5921    }
5922    if (RVAT) {
5923      // FIXME: This isn't correct! But tricky to implement because
5924      // the array's size has to be the size of RHS, but the type
5925      // has to be different.
5926      return RHS;
5927    }
5928    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
5929    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
5930    return getIncompleteArrayType(ResultType,
5931                                  ArrayType::ArraySizeModifier(), 0);
5932  }
5933  case Type::FunctionNoProto:
5934    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
5935  case Type::Record:
5936  case Type::Enum:
5937    return QualType();
5938  case Type::Builtin:
5939    // Only exactly equal builtin types are compatible, which is tested above.
5940    return QualType();
5941  case Type::Complex:
5942    // Distinct complex types are incompatible.
5943    return QualType();
5944  case Type::Vector:
5945    // FIXME: The merged type should be an ExtVector!
5946    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
5947                             RHSCan->getAs<VectorType>()))
5948      return LHS;
5949    return QualType();
5950  case Type::ObjCObject: {
5951    // Check if the types are assignment compatible.
5952    // FIXME: This should be type compatibility, e.g. whether
5953    // "LHS x; RHS x;" at global scope is legal.
5954    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
5955    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
5956    if (canAssignObjCInterfaces(LHSIface, RHSIface))
5957      return LHS;
5958
5959    return QualType();
5960  }
5961  case Type::ObjCObjectPointer: {
5962    if (OfBlockPointer) {
5963      if (canAssignObjCInterfacesInBlockPointer(
5964                                          LHS->getAs<ObjCObjectPointerType>(),
5965                                          RHS->getAs<ObjCObjectPointerType>(),
5966                                          BlockReturnType))
5967      return LHS;
5968      return QualType();
5969    }
5970    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
5971                                RHS->getAs<ObjCObjectPointerType>()))
5972      return LHS;
5973
5974    return QualType();
5975    }
5976  }
5977
5978  return QualType();
5979}
5980
5981bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
5982                   const FunctionProtoType *FromFunctionType,
5983                   const FunctionProtoType *ToFunctionType) {
5984  if (FromFunctionType->hasAnyConsumedArgs() !=
5985      ToFunctionType->hasAnyConsumedArgs())
5986    return false;
5987  FunctionProtoType::ExtProtoInfo FromEPI =
5988    FromFunctionType->getExtProtoInfo();
5989  FunctionProtoType::ExtProtoInfo ToEPI =
5990    ToFunctionType->getExtProtoInfo();
5991  if (FromEPI.ConsumedArguments && ToEPI.ConsumedArguments)
5992    for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs();
5993         ArgIdx != NumArgs; ++ArgIdx)  {
5994      if (FromEPI.ConsumedArguments[ArgIdx] !=
5995          ToEPI.ConsumedArguments[ArgIdx])
5996        return false;
5997    }
5998  return true;
5999}
6000
6001/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
6002/// 'RHS' attributes and returns the merged version; including for function
6003/// return types.
6004QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
6005  QualType LHSCan = getCanonicalType(LHS),
6006  RHSCan = getCanonicalType(RHS);
6007  // If two types are identical, they are compatible.
6008  if (LHSCan == RHSCan)
6009    return LHS;
6010  if (RHSCan->isFunctionType()) {
6011    if (!LHSCan->isFunctionType())
6012      return QualType();
6013    QualType OldReturnType =
6014      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
6015    QualType NewReturnType =
6016      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
6017    QualType ResReturnType =
6018      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
6019    if (ResReturnType.isNull())
6020      return QualType();
6021    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
6022      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
6023      // In either case, use OldReturnType to build the new function type.
6024      const FunctionType *F = LHS->getAs<FunctionType>();
6025      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
6026        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
6027        EPI.ExtInfo = getFunctionExtInfo(LHS);
6028        QualType ResultType
6029          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
6030                            FPT->getNumArgs(), EPI);
6031        return ResultType;
6032      }
6033    }
6034    return QualType();
6035  }
6036
6037  // If the qualifiers are different, the types can still be merged.
6038  Qualifiers LQuals = LHSCan.getLocalQualifiers();
6039  Qualifiers RQuals = RHSCan.getLocalQualifiers();
6040  if (LQuals != RQuals) {
6041    // If any of these qualifiers are different, we have a type mismatch.
6042    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
6043        LQuals.getAddressSpace() != RQuals.getAddressSpace())
6044      return QualType();
6045
6046    // Exactly one GC qualifier difference is allowed: __strong is
6047    // okay if the other type has no GC qualifier but is an Objective
6048    // C object pointer (i.e. implicitly strong by default).  We fix
6049    // this by pretending that the unqualified type was actually
6050    // qualified __strong.
6051    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
6052    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
6053    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
6054
6055    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
6056      return QualType();
6057
6058    if (GC_L == Qualifiers::Strong)
6059      return LHS;
6060    if (GC_R == Qualifiers::Strong)
6061      return RHS;
6062    return QualType();
6063  }
6064
6065  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
6066    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6067    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6068    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
6069    if (ResQT == LHSBaseQT)
6070      return LHS;
6071    if (ResQT == RHSBaseQT)
6072      return RHS;
6073  }
6074  return QualType();
6075}
6076
6077//===----------------------------------------------------------------------===//
6078//                         Integer Predicates
6079//===----------------------------------------------------------------------===//
6080
6081unsigned ASTContext::getIntWidth(QualType T) const {
6082  if (const EnumType *ET = dyn_cast<EnumType>(T))
6083    T = ET->getDecl()->getIntegerType();
6084  if (T->isBooleanType())
6085    return 1;
6086  // For builtin types, just use the standard type sizing method
6087  return (unsigned)getTypeSize(T);
6088}
6089
6090QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
6091  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
6092
6093  // Turn <4 x signed int> -> <4 x unsigned int>
6094  if (const VectorType *VTy = T->getAs<VectorType>())
6095    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
6096                         VTy->getNumElements(), VTy->getVectorKind());
6097
6098  // For enums, we return the unsigned version of the base type.
6099  if (const EnumType *ETy = T->getAs<EnumType>())
6100    T = ETy->getDecl()->getIntegerType();
6101
6102  const BuiltinType *BTy = T->getAs<BuiltinType>();
6103  assert(BTy && "Unexpected signed integer type");
6104  switch (BTy->getKind()) {
6105  case BuiltinType::Char_S:
6106  case BuiltinType::SChar:
6107    return UnsignedCharTy;
6108  case BuiltinType::Short:
6109    return UnsignedShortTy;
6110  case BuiltinType::Int:
6111    return UnsignedIntTy;
6112  case BuiltinType::Long:
6113    return UnsignedLongTy;
6114  case BuiltinType::LongLong:
6115    return UnsignedLongLongTy;
6116  case BuiltinType::Int128:
6117    return UnsignedInt128Ty;
6118  default:
6119    llvm_unreachable("Unexpected signed integer type");
6120  }
6121}
6122
6123ASTMutationListener::~ASTMutationListener() { }
6124
6125
6126//===----------------------------------------------------------------------===//
6127//                          Builtin Type Computation
6128//===----------------------------------------------------------------------===//
6129
6130/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
6131/// pointer over the consumed characters.  This returns the resultant type.  If
6132/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
6133/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
6134/// a vector of "i*".
6135///
6136/// RequiresICE is filled in on return to indicate whether the value is required
6137/// to be an Integer Constant Expression.
6138static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
6139                                  ASTContext::GetBuiltinTypeError &Error,
6140                                  bool &RequiresICE,
6141                                  bool AllowTypeModifiers) {
6142  // Modifiers.
6143  int HowLong = 0;
6144  bool Signed = false, Unsigned = false;
6145  RequiresICE = false;
6146
6147  // Read the prefixed modifiers first.
6148  bool Done = false;
6149  while (!Done) {
6150    switch (*Str++) {
6151    default: Done = true; --Str; break;
6152    case 'I':
6153      RequiresICE = true;
6154      break;
6155    case 'S':
6156      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
6157      assert(!Signed && "Can't use 'S' modifier multiple times!");
6158      Signed = true;
6159      break;
6160    case 'U':
6161      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
6162      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
6163      Unsigned = true;
6164      break;
6165    case 'L':
6166      assert(HowLong <= 2 && "Can't have LLLL modifier");
6167      ++HowLong;
6168      break;
6169    }
6170  }
6171
6172  QualType Type;
6173
6174  // Read the base type.
6175  switch (*Str++) {
6176  default: llvm_unreachable("Unknown builtin type letter!");
6177  case 'v':
6178    assert(HowLong == 0 && !Signed && !Unsigned &&
6179           "Bad modifiers used with 'v'!");
6180    Type = Context.VoidTy;
6181    break;
6182  case 'f':
6183    assert(HowLong == 0 && !Signed && !Unsigned &&
6184           "Bad modifiers used with 'f'!");
6185    Type = Context.FloatTy;
6186    break;
6187  case 'd':
6188    assert(HowLong < 2 && !Signed && !Unsigned &&
6189           "Bad modifiers used with 'd'!");
6190    if (HowLong)
6191      Type = Context.LongDoubleTy;
6192    else
6193      Type = Context.DoubleTy;
6194    break;
6195  case 's':
6196    assert(HowLong == 0 && "Bad modifiers used with 's'!");
6197    if (Unsigned)
6198      Type = Context.UnsignedShortTy;
6199    else
6200      Type = Context.ShortTy;
6201    break;
6202  case 'i':
6203    if (HowLong == 3)
6204      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
6205    else if (HowLong == 2)
6206      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
6207    else if (HowLong == 1)
6208      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
6209    else
6210      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
6211    break;
6212  case 'c':
6213    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
6214    if (Signed)
6215      Type = Context.SignedCharTy;
6216    else if (Unsigned)
6217      Type = Context.UnsignedCharTy;
6218    else
6219      Type = Context.CharTy;
6220    break;
6221  case 'b': // boolean
6222    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
6223    Type = Context.BoolTy;
6224    break;
6225  case 'z':  // size_t.
6226    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
6227    Type = Context.getSizeType();
6228    break;
6229  case 'F':
6230    Type = Context.getCFConstantStringType();
6231    break;
6232  case 'G':
6233    Type = Context.getObjCIdType();
6234    break;
6235  case 'H':
6236    Type = Context.getObjCSelType();
6237    break;
6238  case 'a':
6239    Type = Context.getBuiltinVaListType();
6240    assert(!Type.isNull() && "builtin va list type not initialized!");
6241    break;
6242  case 'A':
6243    // This is a "reference" to a va_list; however, what exactly
6244    // this means depends on how va_list is defined. There are two
6245    // different kinds of va_list: ones passed by value, and ones
6246    // passed by reference.  An example of a by-value va_list is
6247    // x86, where va_list is a char*. An example of by-ref va_list
6248    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
6249    // we want this argument to be a char*&; for x86-64, we want
6250    // it to be a __va_list_tag*.
6251    Type = Context.getBuiltinVaListType();
6252    assert(!Type.isNull() && "builtin va list type not initialized!");
6253    if (Type->isArrayType())
6254      Type = Context.getArrayDecayedType(Type);
6255    else
6256      Type = Context.getLValueReferenceType(Type);
6257    break;
6258  case 'V': {
6259    char *End;
6260    unsigned NumElements = strtoul(Str, &End, 10);
6261    assert(End != Str && "Missing vector size");
6262    Str = End;
6263
6264    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
6265                                             RequiresICE, false);
6266    assert(!RequiresICE && "Can't require vector ICE");
6267
6268    // TODO: No way to make AltiVec vectors in builtins yet.
6269    Type = Context.getVectorType(ElementType, NumElements,
6270                                 VectorType::GenericVector);
6271    break;
6272  }
6273  case 'X': {
6274    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
6275                                             false);
6276    assert(!RequiresICE && "Can't require complex ICE");
6277    Type = Context.getComplexType(ElementType);
6278    break;
6279  }
6280  case 'Y' : {
6281    Type = Context.getPointerDiffType();
6282    break;
6283  }
6284  case 'P':
6285    Type = Context.getFILEType();
6286    if (Type.isNull()) {
6287      Error = ASTContext::GE_Missing_stdio;
6288      return QualType();
6289    }
6290    break;
6291  case 'J':
6292    if (Signed)
6293      Type = Context.getsigjmp_bufType();
6294    else
6295      Type = Context.getjmp_bufType();
6296
6297    if (Type.isNull()) {
6298      Error = ASTContext::GE_Missing_setjmp;
6299      return QualType();
6300    }
6301    break;
6302  }
6303
6304  // If there are modifiers and if we're allowed to parse them, go for it.
6305  Done = !AllowTypeModifiers;
6306  while (!Done) {
6307    switch (char c = *Str++) {
6308    default: Done = true; --Str; break;
6309    case '*':
6310    case '&': {
6311      // Both pointers and references can have their pointee types
6312      // qualified with an address space.
6313      char *End;
6314      unsigned AddrSpace = strtoul(Str, &End, 10);
6315      if (End != Str && AddrSpace != 0) {
6316        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
6317        Str = End;
6318      }
6319      if (c == '*')
6320        Type = Context.getPointerType(Type);
6321      else
6322        Type = Context.getLValueReferenceType(Type);
6323      break;
6324    }
6325    // FIXME: There's no way to have a built-in with an rvalue ref arg.
6326    case 'C':
6327      Type = Type.withConst();
6328      break;
6329    case 'D':
6330      Type = Context.getVolatileType(Type);
6331      break;
6332    }
6333  }
6334
6335  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
6336         "Integer constant 'I' type must be an integer");
6337
6338  return Type;
6339}
6340
6341/// GetBuiltinType - Return the type for the specified builtin.
6342QualType ASTContext::GetBuiltinType(unsigned Id,
6343                                    GetBuiltinTypeError &Error,
6344                                    unsigned *IntegerConstantArgs) const {
6345  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
6346
6347  SmallVector<QualType, 8> ArgTypes;
6348
6349  bool RequiresICE = false;
6350  Error = GE_None;
6351  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
6352                                       RequiresICE, true);
6353  if (Error != GE_None)
6354    return QualType();
6355
6356  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
6357
6358  while (TypeStr[0] && TypeStr[0] != '.') {
6359    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
6360    if (Error != GE_None)
6361      return QualType();
6362
6363    // If this argument is required to be an IntegerConstantExpression and the
6364    // caller cares, fill in the bitmask we return.
6365    if (RequiresICE && IntegerConstantArgs)
6366      *IntegerConstantArgs |= 1 << ArgTypes.size();
6367
6368    // Do array -> pointer decay.  The builtin should use the decayed type.
6369    if (Ty->isArrayType())
6370      Ty = getArrayDecayedType(Ty);
6371
6372    ArgTypes.push_back(Ty);
6373  }
6374
6375  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
6376         "'.' should only occur at end of builtin type list!");
6377
6378  FunctionType::ExtInfo EI;
6379  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
6380
6381  bool Variadic = (TypeStr[0] == '.');
6382
6383  // We really shouldn't be making a no-proto type here, especially in C++.
6384  if (ArgTypes.empty() && Variadic)
6385    return getFunctionNoProtoType(ResType, EI);
6386
6387  FunctionProtoType::ExtProtoInfo EPI;
6388  EPI.ExtInfo = EI;
6389  EPI.Variadic = Variadic;
6390
6391  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(), EPI);
6392}
6393
6394GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
6395  GVALinkage External = GVA_StrongExternal;
6396
6397  Linkage L = FD->getLinkage();
6398  switch (L) {
6399  case NoLinkage:
6400  case InternalLinkage:
6401  case UniqueExternalLinkage:
6402    return GVA_Internal;
6403
6404  case ExternalLinkage:
6405    switch (FD->getTemplateSpecializationKind()) {
6406    case TSK_Undeclared:
6407    case TSK_ExplicitSpecialization:
6408      External = GVA_StrongExternal;
6409      break;
6410
6411    case TSK_ExplicitInstantiationDefinition:
6412      return GVA_ExplicitTemplateInstantiation;
6413
6414    case TSK_ExplicitInstantiationDeclaration:
6415    case TSK_ImplicitInstantiation:
6416      External = GVA_TemplateInstantiation;
6417      break;
6418    }
6419  }
6420
6421  if (!FD->isInlined())
6422    return External;
6423
6424  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
6425    // GNU or C99 inline semantics. Determine whether this symbol should be
6426    // externally visible.
6427    if (FD->isInlineDefinitionExternallyVisible())
6428      return External;
6429
6430    // C99 inline semantics, where the symbol is not externally visible.
6431    return GVA_C99Inline;
6432  }
6433
6434  // C++0x [temp.explicit]p9:
6435  //   [ Note: The intent is that an inline function that is the subject of
6436  //   an explicit instantiation declaration will still be implicitly
6437  //   instantiated when used so that the body can be considered for
6438  //   inlining, but that no out-of-line copy of the inline function would be
6439  //   generated in the translation unit. -- end note ]
6440  if (FD->getTemplateSpecializationKind()
6441                                       == TSK_ExplicitInstantiationDeclaration)
6442    return GVA_C99Inline;
6443
6444  return GVA_CXXInline;
6445}
6446
6447GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
6448  // If this is a static data member, compute the kind of template
6449  // specialization. Otherwise, this variable is not part of a
6450  // template.
6451  TemplateSpecializationKind TSK = TSK_Undeclared;
6452  if (VD->isStaticDataMember())
6453    TSK = VD->getTemplateSpecializationKind();
6454
6455  Linkage L = VD->getLinkage();
6456  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
6457      VD->getType()->getLinkage() == UniqueExternalLinkage)
6458    L = UniqueExternalLinkage;
6459
6460  switch (L) {
6461  case NoLinkage:
6462  case InternalLinkage:
6463  case UniqueExternalLinkage:
6464    return GVA_Internal;
6465
6466  case ExternalLinkage:
6467    switch (TSK) {
6468    case TSK_Undeclared:
6469    case TSK_ExplicitSpecialization:
6470      return GVA_StrongExternal;
6471
6472    case TSK_ExplicitInstantiationDeclaration:
6473      llvm_unreachable("Variable should not be instantiated");
6474      // Fall through to treat this like any other instantiation.
6475
6476    case TSK_ExplicitInstantiationDefinition:
6477      return GVA_ExplicitTemplateInstantiation;
6478
6479    case TSK_ImplicitInstantiation:
6480      return GVA_TemplateInstantiation;
6481    }
6482  }
6483
6484  return GVA_StrongExternal;
6485}
6486
6487bool ASTContext::DeclMustBeEmitted(const Decl *D) {
6488  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
6489    if (!VD->isFileVarDecl())
6490      return false;
6491  } else if (!isa<FunctionDecl>(D))
6492    return false;
6493
6494  // Weak references don't produce any output by themselves.
6495  if (D->hasAttr<WeakRefAttr>())
6496    return false;
6497
6498  // Aliases and used decls are required.
6499  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
6500    return true;
6501
6502  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
6503    // Forward declarations aren't required.
6504    if (!FD->doesThisDeclarationHaveABody())
6505      return FD->doesDeclarationForceExternallyVisibleDefinition();
6506
6507    // Constructors and destructors are required.
6508    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
6509      return true;
6510
6511    // The key function for a class is required.
6512    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
6513      const CXXRecordDecl *RD = MD->getParent();
6514      if (MD->isOutOfLine() && RD->isDynamicClass()) {
6515        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
6516        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
6517          return true;
6518      }
6519    }
6520
6521    GVALinkage Linkage = GetGVALinkageForFunction(FD);
6522
6523    // static, static inline, always_inline, and extern inline functions can
6524    // always be deferred.  Normal inline functions can be deferred in C99/C++.
6525    // Implicit template instantiations can also be deferred in C++.
6526    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
6527        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
6528      return false;
6529    return true;
6530  }
6531
6532  const VarDecl *VD = cast<VarDecl>(D);
6533  assert(VD->isFileVarDecl() && "Expected file scoped var");
6534
6535  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
6536    return false;
6537
6538  // Structs that have non-trivial constructors or destructors are required.
6539
6540  // FIXME: Handle references.
6541  // FIXME: Be more selective about which constructors we care about.
6542  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
6543    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
6544      if (RD->hasDefinition() && !(RD->hasTrivialDefaultConstructor() &&
6545                                   RD->hasTrivialCopyConstructor() &&
6546                                   RD->hasTrivialMoveConstructor() &&
6547                                   RD->hasTrivialDestructor()))
6548        return true;
6549    }
6550  }
6551
6552  GVALinkage L = GetGVALinkageForVariable(VD);
6553  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
6554    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
6555      return false;
6556  }
6557
6558  return true;
6559}
6560
6561CallingConv ASTContext::getDefaultMethodCallConv() {
6562  // Pass through to the C++ ABI object
6563  return ABI->getDefaultMethodCallConv();
6564}
6565
6566bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
6567  // Pass through to the C++ ABI object
6568  return ABI->isNearlyEmpty(RD);
6569}
6570
6571MangleContext *ASTContext::createMangleContext() {
6572  switch (Target->getCXXABI()) {
6573  case CXXABI_ARM:
6574  case CXXABI_Itanium:
6575    return createItaniumMangleContext(*this, getDiagnostics());
6576  case CXXABI_Microsoft:
6577    return createMicrosoftMangleContext(*this, getDiagnostics());
6578  }
6579  llvm_unreachable("Unsupported ABI");
6580}
6581
6582CXXABI::~CXXABI() {}
6583
6584size_t ASTContext::getSideTableAllocatedMemory() const {
6585  return ASTRecordLayouts.getMemorySize()
6586    + llvm::capacity_in_bytes(ObjCLayouts)
6587    + llvm::capacity_in_bytes(KeyFunctions)
6588    + llvm::capacity_in_bytes(ObjCImpls)
6589    + llvm::capacity_in_bytes(BlockVarCopyInits)
6590    + llvm::capacity_in_bytes(DeclAttrs)
6591    + llvm::capacity_in_bytes(InstantiatedFromStaticDataMember)
6592    + llvm::capacity_in_bytes(InstantiatedFromUsingDecl)
6593    + llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl)
6594    + llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl)
6595    + llvm::capacity_in_bytes(OverriddenMethods)
6596    + llvm::capacity_in_bytes(Types)
6597    + llvm::capacity_in_bytes(VariableArrayTypes)
6598    + llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
6599}
6600
6601void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
6602  ParamIndices[D] = index;
6603}
6604
6605unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
6606  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
6607  assert(I != ParamIndices.end() &&
6608         "ParmIndices lacks entry set by ParmVarDecl");
6609  return I->second;
6610}
6611