ASTContext.cpp revision 327a50f46449c946c42d50d97689bcb30e2af7d9 
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  // "any" type; useful for debugger-like clients.
465  InitBuiltinType(UnknownAnyTy,        BuiltinType::UnknownAny);
466
467  // Placeholder type for unbridged ARC casts.
468  InitBuiltinType(ARCUnbridgedCastTy,  BuiltinType::ARCUnbridgedCast);
469
470  // C99 6.2.5p11.
471  FloatComplexTy      = getComplexType(FloatTy);
472  DoubleComplexTy     = getComplexType(DoubleTy);
473  LongDoubleComplexTy = getComplexType(LongDoubleTy);
474
475  BuiltinVaListType = QualType();
476
477  // Builtin types for 'id', 'Class', and 'SEL'.
478  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
479  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
480  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
481
482  ObjCConstantStringType = QualType();
483
484  // void * type
485  VoidPtrTy = getPointerType(VoidTy);
486
487  // nullptr type (C++0x 2.14.7)
488  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
489
490  // half type (OpenCL 6.1.1.1) / ARM NEON __fp16
491  InitBuiltinType(HalfTy, BuiltinType::Half);
492}
493
494DiagnosticsEngine &ASTContext::getDiagnostics() const {
495  return SourceMgr.getDiagnostics();
496}
497
498AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
499  AttrVec *&Result = DeclAttrs[D];
500  if (!Result) {
501    void *Mem = Allocate(sizeof(AttrVec));
502    Result = new (Mem) AttrVec;
503  }
504
505  return *Result;
506}
507
508/// \brief Erase the attributes corresponding to the given declaration.
509void ASTContext::eraseDeclAttrs(const Decl *D) {
510  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
511  if (Pos != DeclAttrs.end()) {
512    Pos->second->~AttrVec();
513    DeclAttrs.erase(Pos);
514  }
515}
516
517MemberSpecializationInfo *
518ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
519  assert(Var->isStaticDataMember() && "Not a static data member");
520  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
521    = InstantiatedFromStaticDataMember.find(Var);
522  if (Pos == InstantiatedFromStaticDataMember.end())
523    return 0;
524
525  return Pos->second;
526}
527
528void
529ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
530                                                TemplateSpecializationKind TSK,
531                                          SourceLocation PointOfInstantiation) {
532  assert(Inst->isStaticDataMember() && "Not a static data member");
533  assert(Tmpl->isStaticDataMember() && "Not a static data member");
534  assert(!InstantiatedFromStaticDataMember[Inst] &&
535         "Already noted what static data member was instantiated from");
536  InstantiatedFromStaticDataMember[Inst]
537    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
538}
539
540FunctionDecl *ASTContext::getClassScopeSpecializationPattern(
541                                                     const FunctionDecl *FD){
542  assert(FD && "Specialization is 0");
543  llvm::DenseMap<const FunctionDecl*, FunctionDecl *>::const_iterator Pos
544    = ClassScopeSpecializationPattern.find(FD);
545  if (Pos == ClassScopeSpecializationPattern.end())
546    return 0;
547
548  return Pos->second;
549}
550
551void ASTContext::setClassScopeSpecializationPattern(FunctionDecl *FD,
552                                        FunctionDecl *Pattern) {
553  assert(FD && "Specialization is 0");
554  assert(Pattern && "Class scope specialization pattern is 0");
555  ClassScopeSpecializationPattern[FD] = Pattern;
556}
557
558NamedDecl *
559ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
560  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
561    = InstantiatedFromUsingDecl.find(UUD);
562  if (Pos == InstantiatedFromUsingDecl.end())
563    return 0;
564
565  return Pos->second;
566}
567
568void
569ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
570  assert((isa<UsingDecl>(Pattern) ||
571          isa<UnresolvedUsingValueDecl>(Pattern) ||
572          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
573         "pattern decl is not a using decl");
574  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
575  InstantiatedFromUsingDecl[Inst] = Pattern;
576}
577
578UsingShadowDecl *
579ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
580  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
581    = InstantiatedFromUsingShadowDecl.find(Inst);
582  if (Pos == InstantiatedFromUsingShadowDecl.end())
583    return 0;
584
585  return Pos->second;
586}
587
588void
589ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
590                                               UsingShadowDecl *Pattern) {
591  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
592  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
593}
594
595FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
596  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
597    = InstantiatedFromUnnamedFieldDecl.find(Field);
598  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
599    return 0;
600
601  return Pos->second;
602}
603
604void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
605                                                     FieldDecl *Tmpl) {
606  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
607  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
608  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
609         "Already noted what unnamed field was instantiated from");
610
611  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
612}
613
614bool ASTContext::ZeroBitfieldFollowsNonBitfield(const FieldDecl *FD,
615                                    const FieldDecl *LastFD) const {
616  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
617          FD->getBitWidthValue(*this) == 0);
618}
619
620bool ASTContext::ZeroBitfieldFollowsBitfield(const FieldDecl *FD,
621                                             const FieldDecl *LastFD) const {
622  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
623          FD->getBitWidthValue(*this) == 0 &&
624          LastFD->getBitWidthValue(*this) != 0);
625}
626
627bool ASTContext::BitfieldFollowsBitfield(const FieldDecl *FD,
628                                         const FieldDecl *LastFD) const {
629  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
630          FD->getBitWidthValue(*this) &&
631          LastFD->getBitWidthValue(*this));
632}
633
634bool ASTContext::NonBitfieldFollowsBitfield(const FieldDecl *FD,
635                                         const FieldDecl *LastFD) const {
636  return (!FD->isBitField() && LastFD && LastFD->isBitField() &&
637          LastFD->getBitWidthValue(*this));
638}
639
640bool ASTContext::BitfieldFollowsNonBitfield(const FieldDecl *FD,
641                                             const FieldDecl *LastFD) const {
642  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
643          FD->getBitWidthValue(*this));
644}
645
646ASTContext::overridden_cxx_method_iterator
647ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
648  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
649    = OverriddenMethods.find(Method);
650  if (Pos == OverriddenMethods.end())
651    return 0;
652
653  return Pos->second.begin();
654}
655
656ASTContext::overridden_cxx_method_iterator
657ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
658  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
659    = OverriddenMethods.find(Method);
660  if (Pos == OverriddenMethods.end())
661    return 0;
662
663  return Pos->second.end();
664}
665
666unsigned
667ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
668  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
669    = OverriddenMethods.find(Method);
670  if (Pos == OverriddenMethods.end())
671    return 0;
672
673  return Pos->second.size();
674}
675
676void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
677                                     const CXXMethodDecl *Overridden) {
678  OverriddenMethods[Method].push_back(Overridden);
679}
680
681//===----------------------------------------------------------------------===//
682//                         Type Sizing and Analysis
683//===----------------------------------------------------------------------===//
684
685/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
686/// scalar floating point type.
687const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
688  const BuiltinType *BT = T->getAs<BuiltinType>();
689  assert(BT && "Not a floating point type!");
690  switch (BT->getKind()) {
691  default: llvm_unreachable("Not a floating point type!");
692  case BuiltinType::Half:       return Target->getHalfFormat();
693  case BuiltinType::Float:      return Target->getFloatFormat();
694  case BuiltinType::Double:     return Target->getDoubleFormat();
695  case BuiltinType::LongDouble: return Target->getLongDoubleFormat();
696  }
697}
698
699/// getDeclAlign - Return a conservative estimate of the alignment of the
700/// specified decl.  Note that bitfields do not have a valid alignment, so
701/// this method will assert on them.
702/// If @p RefAsPointee, references are treated like their underlying type
703/// (for alignof), else they're treated like pointers (for CodeGen).
704CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) const {
705  unsigned Align = Target->getCharWidth();
706
707  bool UseAlignAttrOnly = false;
708  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
709    Align = AlignFromAttr;
710
711    // __attribute__((aligned)) can increase or decrease alignment
712    // *except* on a struct or struct member, where it only increases
713    // alignment unless 'packed' is also specified.
714    //
715    // It is an error for alignas to decrease alignment, so we can
716    // ignore that possibility;  Sema should diagnose it.
717    if (isa<FieldDecl>(D)) {
718      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
719        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
720    } else {
721      UseAlignAttrOnly = true;
722    }
723  }
724  else if (isa<FieldDecl>(D))
725      UseAlignAttrOnly =
726        D->hasAttr<PackedAttr>() ||
727        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
728
729  // If we're using the align attribute only, just ignore everything
730  // else about the declaration and its type.
731  if (UseAlignAttrOnly) {
732    // do nothing
733
734  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
735    QualType T = VD->getType();
736    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
737      if (RefAsPointee)
738        T = RT->getPointeeType();
739      else
740        T = getPointerType(RT->getPointeeType());
741    }
742    if (!T->isIncompleteType() && !T->isFunctionType()) {
743      // Adjust alignments of declarations with array type by the
744      // large-array alignment on the target.
745      unsigned MinWidth = Target->getLargeArrayMinWidth();
746      const ArrayType *arrayType;
747      if (MinWidth && (arrayType = getAsArrayType(T))) {
748        if (isa<VariableArrayType>(arrayType))
749          Align = std::max(Align, Target->getLargeArrayAlign());
750        else if (isa<ConstantArrayType>(arrayType) &&
751                 MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
752          Align = std::max(Align, Target->getLargeArrayAlign());
753
754        // Walk through any array types while we're at it.
755        T = getBaseElementType(arrayType);
756      }
757      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
758    }
759
760    // Fields can be subject to extra alignment constraints, like if
761    // the field is packed, the struct is packed, or the struct has a
762    // a max-field-alignment constraint (#pragma pack).  So calculate
763    // the actual alignment of the field within the struct, and then
764    // (as we're expected to) constrain that by the alignment of the type.
765    if (const FieldDecl *field = dyn_cast<FieldDecl>(VD)) {
766      // So calculate the alignment of the field.
767      const ASTRecordLayout &layout = getASTRecordLayout(field->getParent());
768
769      // Start with the record's overall alignment.
770      unsigned fieldAlign = toBits(layout.getAlignment());
771
772      // Use the GCD of that and the offset within the record.
773      uint64_t offset = layout.getFieldOffset(field->getFieldIndex());
774      if (offset > 0) {
775        // Alignment is always a power of 2, so the GCD will be a power of 2,
776        // which means we get to do this crazy thing instead of Euclid's.
777        uint64_t lowBitOfOffset = offset & (~offset + 1);
778        if (lowBitOfOffset < fieldAlign)
779          fieldAlign = static_cast<unsigned>(lowBitOfOffset);
780      }
781
782      Align = std::min(Align, fieldAlign);
783    }
784  }
785
786  return toCharUnitsFromBits(Align);
787}
788
789std::pair<CharUnits, CharUnits>
790ASTContext::getTypeInfoInChars(const Type *T) const {
791  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
792  return std::make_pair(toCharUnitsFromBits(Info.first),
793                        toCharUnitsFromBits(Info.second));
794}
795
796std::pair<CharUnits, CharUnits>
797ASTContext::getTypeInfoInChars(QualType T) const {
798  return getTypeInfoInChars(T.getTypePtr());
799}
800
801/// getTypeSize - Return the size of the specified type, in bits.  This method
802/// does not work on incomplete types.
803///
804/// FIXME: Pointers into different addr spaces could have different sizes and
805/// alignment requirements: getPointerInfo should take an AddrSpace, this
806/// should take a QualType, &c.
807std::pair<uint64_t, unsigned>
808ASTContext::getTypeInfo(const Type *T) const {
809  uint64_t Width=0;
810  unsigned Align=8;
811  switch (T->getTypeClass()) {
812#define TYPE(Class, Base)
813#define ABSTRACT_TYPE(Class, Base)
814#define NON_CANONICAL_TYPE(Class, Base)
815#define DEPENDENT_TYPE(Class, Base) case Type::Class:
816#include "clang/AST/TypeNodes.def"
817    llvm_unreachable("Should not see dependent types");
818    break;
819
820  case Type::FunctionNoProto:
821  case Type::FunctionProto:
822    // GCC extension: alignof(function) = 32 bits
823    Width = 0;
824    Align = 32;
825    break;
826
827  case Type::IncompleteArray:
828  case Type::VariableArray:
829    Width = 0;
830    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
831    break;
832
833  case Type::ConstantArray: {
834    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
835
836    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
837    Width = EltInfo.first*CAT->getSize().getZExtValue();
838    Align = EltInfo.second;
839    Width = llvm::RoundUpToAlignment(Width, Align);
840    break;
841  }
842  case Type::ExtVector:
843  case Type::Vector: {
844    const VectorType *VT = cast<VectorType>(T);
845    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
846    Width = EltInfo.first*VT->getNumElements();
847    Align = Width;
848    // If the alignment is not a power of 2, round up to the next power of 2.
849    // This happens for non-power-of-2 length vectors.
850    if (Align & (Align-1)) {
851      Align = llvm::NextPowerOf2(Align);
852      Width = llvm::RoundUpToAlignment(Width, Align);
853    }
854    break;
855  }
856
857  case Type::Builtin:
858    switch (cast<BuiltinType>(T)->getKind()) {
859    default: llvm_unreachable("Unknown builtin type!");
860    case BuiltinType::Void:
861      // GCC extension: alignof(void) = 8 bits.
862      Width = 0;
863      Align = 8;
864      break;
865
866    case BuiltinType::Bool:
867      Width = Target->getBoolWidth();
868      Align = Target->getBoolAlign();
869      break;
870    case BuiltinType::Char_S:
871    case BuiltinType::Char_U:
872    case BuiltinType::UChar:
873    case BuiltinType::SChar:
874      Width = Target->getCharWidth();
875      Align = Target->getCharAlign();
876      break;
877    case BuiltinType::WChar_S:
878    case BuiltinType::WChar_U:
879      Width = Target->getWCharWidth();
880      Align = Target->getWCharAlign();
881      break;
882    case BuiltinType::Char16:
883      Width = Target->getChar16Width();
884      Align = Target->getChar16Align();
885      break;
886    case BuiltinType::Char32:
887      Width = Target->getChar32Width();
888      Align = Target->getChar32Align();
889      break;
890    case BuiltinType::UShort:
891    case BuiltinType::Short:
892      Width = Target->getShortWidth();
893      Align = Target->getShortAlign();
894      break;
895    case BuiltinType::UInt:
896    case BuiltinType::Int:
897      Width = Target->getIntWidth();
898      Align = Target->getIntAlign();
899      break;
900    case BuiltinType::ULong:
901    case BuiltinType::Long:
902      Width = Target->getLongWidth();
903      Align = Target->getLongAlign();
904      break;
905    case BuiltinType::ULongLong:
906    case BuiltinType::LongLong:
907      Width = Target->getLongLongWidth();
908      Align = Target->getLongLongAlign();
909      break;
910    case BuiltinType::Int128:
911    case BuiltinType::UInt128:
912      Width = 128;
913      Align = 128; // int128_t is 128-bit aligned on all targets.
914      break;
915    case BuiltinType::Half:
916      Width = Target->getHalfWidth();
917      Align = Target->getHalfAlign();
918      break;
919    case BuiltinType::Float:
920      Width = Target->getFloatWidth();
921      Align = Target->getFloatAlign();
922      break;
923    case BuiltinType::Double:
924      Width = Target->getDoubleWidth();
925      Align = Target->getDoubleAlign();
926      break;
927    case BuiltinType::LongDouble:
928      Width = Target->getLongDoubleWidth();
929      Align = Target->getLongDoubleAlign();
930      break;
931    case BuiltinType::NullPtr:
932      Width = Target->getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
933      Align = Target->getPointerAlign(0); //   == sizeof(void*)
934      break;
935    case BuiltinType::ObjCId:
936    case BuiltinType::ObjCClass:
937    case BuiltinType::ObjCSel:
938      Width = Target->getPointerWidth(0);
939      Align = Target->getPointerAlign(0);
940      break;
941    }
942    break;
943  case Type::ObjCObjectPointer:
944    Width = Target->getPointerWidth(0);
945    Align = Target->getPointerAlign(0);
946    break;
947  case Type::BlockPointer: {
948    unsigned AS = getTargetAddressSpace(
949        cast<BlockPointerType>(T)->getPointeeType());
950    Width = Target->getPointerWidth(AS);
951    Align = Target->getPointerAlign(AS);
952    break;
953  }
954  case Type::LValueReference:
955  case Type::RValueReference: {
956    // alignof and sizeof should never enter this code path here, so we go
957    // the pointer route.
958    unsigned AS = getTargetAddressSpace(
959        cast<ReferenceType>(T)->getPointeeType());
960    Width = Target->getPointerWidth(AS);
961    Align = Target->getPointerAlign(AS);
962    break;
963  }
964  case Type::Pointer: {
965    unsigned AS = getTargetAddressSpace(cast<PointerType>(T)->getPointeeType());
966    Width = Target->getPointerWidth(AS);
967    Align = Target->getPointerAlign(AS);
968    break;
969  }
970  case Type::MemberPointer: {
971    const MemberPointerType *MPT = cast<MemberPointerType>(T);
972    std::pair<uint64_t, unsigned> PtrDiffInfo =
973      getTypeInfo(getPointerDiffType());
974    Width = PtrDiffInfo.first * ABI->getMemberPointerSize(MPT);
975    Align = PtrDiffInfo.second;
976    break;
977  }
978  case Type::Complex: {
979    // Complex types have the same alignment as their elements, but twice the
980    // size.
981    std::pair<uint64_t, unsigned> EltInfo =
982      getTypeInfo(cast<ComplexType>(T)->getElementType());
983    Width = EltInfo.first*2;
984    Align = EltInfo.second;
985    break;
986  }
987  case Type::ObjCObject:
988    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
989  case Type::ObjCInterface: {
990    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
991    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
992    Width = toBits(Layout.getSize());
993    Align = toBits(Layout.getAlignment());
994    break;
995  }
996  case Type::Record:
997  case Type::Enum: {
998    const TagType *TT = cast<TagType>(T);
999
1000    if (TT->getDecl()->isInvalidDecl()) {
1001      Width = 8;
1002      Align = 8;
1003      break;
1004    }
1005
1006    if (const EnumType *ET = dyn_cast<EnumType>(TT))
1007      return getTypeInfo(ET->getDecl()->getIntegerType());
1008
1009    const RecordType *RT = cast<RecordType>(TT);
1010    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
1011    Width = toBits(Layout.getSize());
1012    Align = toBits(Layout.getAlignment());
1013    break;
1014  }
1015
1016  case Type::SubstTemplateTypeParm:
1017    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
1018                       getReplacementType().getTypePtr());
1019
1020  case Type::Auto: {
1021    const AutoType *A = cast<AutoType>(T);
1022    assert(A->isDeduced() && "Cannot request the size of a dependent type");
1023    return getTypeInfo(A->getDeducedType().getTypePtr());
1024  }
1025
1026  case Type::Paren:
1027    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
1028
1029  case Type::Typedef: {
1030    const TypedefNameDecl *Typedef = cast<TypedefType>(T)->getDecl();
1031    std::pair<uint64_t, unsigned> Info
1032      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
1033    // If the typedef has an aligned attribute on it, it overrides any computed
1034    // alignment we have.  This violates the GCC documentation (which says that
1035    // attribute(aligned) can only round up) but matches its implementation.
1036    if (unsigned AttrAlign = Typedef->getMaxAlignment())
1037      Align = AttrAlign;
1038    else
1039      Align = Info.second;
1040    Width = Info.first;
1041    break;
1042  }
1043
1044  case Type::TypeOfExpr:
1045    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
1046                         .getTypePtr());
1047
1048  case Type::TypeOf:
1049    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
1050
1051  case Type::Decltype:
1052    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
1053                        .getTypePtr());
1054
1055  case Type::UnaryTransform:
1056    return getTypeInfo(cast<UnaryTransformType>(T)->getUnderlyingType());
1057
1058  case Type::Elaborated:
1059    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
1060
1061  case Type::Attributed:
1062    return getTypeInfo(
1063                  cast<AttributedType>(T)->getEquivalentType().getTypePtr());
1064
1065  case Type::TemplateSpecialization: {
1066    assert(getCanonicalType(T) != T &&
1067           "Cannot request the size of a dependent type");
1068    const TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T);
1069    // A type alias template specialization may refer to a typedef with the
1070    // aligned attribute on it.
1071    if (TST->isTypeAlias())
1072      return getTypeInfo(TST->getAliasedType().getTypePtr());
1073    else
1074      return getTypeInfo(getCanonicalType(T));
1075  }
1076
1077  case Type::Atomic: {
1078    std::pair<uint64_t, unsigned> Info
1079      = getTypeInfo(cast<AtomicType>(T)->getValueType());
1080    Width = Info.first;
1081    Align = Info.second;
1082    if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth() &&
1083        llvm::isPowerOf2_64(Width)) {
1084      // We can potentially perform lock-free atomic operations for this
1085      // type; promote the alignment appropriately.
1086      // FIXME: We could potentially promote the width here as well...
1087      // is that worthwhile?  (Non-struct atomic types generally have
1088      // power-of-two size anyway, but structs might not.  Requires a bit
1089      // of implementation work to make sure we zero out the extra bits.)
1090      Align = static_cast<unsigned>(Width);
1091    }
1092  }
1093
1094  }
1095
1096  assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
1097  return std::make_pair(Width, Align);
1098}
1099
1100/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1101CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1102  return CharUnits::fromQuantity(BitSize / getCharWidth());
1103}
1104
1105/// toBits - Convert a size in characters to a size in characters.
1106int64_t ASTContext::toBits(CharUnits CharSize) const {
1107  return CharSize.getQuantity() * getCharWidth();
1108}
1109
1110/// getTypeSizeInChars - Return the size of the specified type, in characters.
1111/// This method does not work on incomplete types.
1112CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1113  return toCharUnitsFromBits(getTypeSize(T));
1114}
1115CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1116  return toCharUnitsFromBits(getTypeSize(T));
1117}
1118
1119/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1120/// characters. This method does not work on incomplete types.
1121CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1122  return toCharUnitsFromBits(getTypeAlign(T));
1123}
1124CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1125  return toCharUnitsFromBits(getTypeAlign(T));
1126}
1127
1128/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1129/// type for the current target in bits.  This can be different than the ABI
1130/// alignment in cases where it is beneficial for performance to overalign
1131/// a data type.
1132unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1133  unsigned ABIAlign = getTypeAlign(T);
1134
1135  // Double and long long should be naturally aligned if possible.
1136  if (const ComplexType* CT = T->getAs<ComplexType>())
1137    T = CT->getElementType().getTypePtr();
1138  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1139      T->isSpecificBuiltinType(BuiltinType::LongLong))
1140    return std::max(ABIAlign, (unsigned)getTypeSize(T));
1141
1142  return ABIAlign;
1143}
1144
1145/// DeepCollectObjCIvars -
1146/// This routine first collects all declared, but not synthesized, ivars in
1147/// super class and then collects all ivars, including those synthesized for
1148/// current class. This routine is used for implementation of current class
1149/// when all ivars, declared and synthesized are known.
1150///
1151void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1152                                      bool leafClass,
1153                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1154  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1155    DeepCollectObjCIvars(SuperClass, false, Ivars);
1156  if (!leafClass) {
1157    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
1158         E = OI->ivar_end(); I != E; ++I)
1159      Ivars.push_back(*I);
1160  } else {
1161    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1162    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1163         Iv= Iv->getNextIvar())
1164      Ivars.push_back(Iv);
1165  }
1166}
1167
1168/// CollectInheritedProtocols - Collect all protocols in current class and
1169/// those inherited by it.
1170void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1171                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1172  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1173    // We can use protocol_iterator here instead of
1174    // all_referenced_protocol_iterator since we are walking all categories.
1175    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
1176         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
1177      ObjCProtocolDecl *Proto = (*P);
1178      Protocols.insert(Proto);
1179      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1180           PE = Proto->protocol_end(); P != PE; ++P) {
1181        Protocols.insert(*P);
1182        CollectInheritedProtocols(*P, Protocols);
1183      }
1184    }
1185
1186    // Categories of this Interface.
1187    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
1188         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
1189      CollectInheritedProtocols(CDeclChain, Protocols);
1190    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1191      while (SD) {
1192        CollectInheritedProtocols(SD, Protocols);
1193        SD = SD->getSuperClass();
1194      }
1195  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1196    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
1197         PE = OC->protocol_end(); P != PE; ++P) {
1198      ObjCProtocolDecl *Proto = (*P);
1199      Protocols.insert(Proto);
1200      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1201           PE = Proto->protocol_end(); P != PE; ++P)
1202        CollectInheritedProtocols(*P, Protocols);
1203    }
1204  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
1205    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
1206         PE = OP->protocol_end(); P != PE; ++P) {
1207      ObjCProtocolDecl *Proto = (*P);
1208      Protocols.insert(Proto);
1209      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1210           PE = Proto->protocol_end(); P != PE; ++P)
1211        CollectInheritedProtocols(*P, Protocols);
1212    }
1213  }
1214}
1215
1216unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
1217  unsigned count = 0;
1218  // Count ivars declared in class extension.
1219  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
1220       CDecl = CDecl->getNextClassExtension())
1221    count += CDecl->ivar_size();
1222
1223  // Count ivar defined in this class's implementation.  This
1224  // includes synthesized ivars.
1225  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
1226    count += ImplDecl->ivar_size();
1227
1228  return count;
1229}
1230
1231/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
1232ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
1233  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1234    I = ObjCImpls.find(D);
1235  if (I != ObjCImpls.end())
1236    return cast<ObjCImplementationDecl>(I->second);
1237  return 0;
1238}
1239/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
1240ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
1241  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1242    I = ObjCImpls.find(D);
1243  if (I != ObjCImpls.end())
1244    return cast<ObjCCategoryImplDecl>(I->second);
1245  return 0;
1246}
1247
1248/// \brief Set the implementation of ObjCInterfaceDecl.
1249void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1250                           ObjCImplementationDecl *ImplD) {
1251  assert(IFaceD && ImplD && "Passed null params");
1252  ObjCImpls[IFaceD] = ImplD;
1253}
1254/// \brief Set the implementation of ObjCCategoryDecl.
1255void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1256                           ObjCCategoryImplDecl *ImplD) {
1257  assert(CatD && ImplD && "Passed null params");
1258  ObjCImpls[CatD] = ImplD;
1259}
1260
1261/// \brief Get the copy initialization expression of VarDecl,or NULL if
1262/// none exists.
1263Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
1264  assert(VD && "Passed null params");
1265  assert(VD->hasAttr<BlocksAttr>() &&
1266         "getBlockVarCopyInits - not __block var");
1267  llvm::DenseMap<const VarDecl*, Expr*>::iterator
1268    I = BlockVarCopyInits.find(VD);
1269  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : 0;
1270}
1271
1272/// \brief Set the copy inialization expression of a block var decl.
1273void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
1274  assert(VD && Init && "Passed null params");
1275  assert(VD->hasAttr<BlocksAttr>() &&
1276         "setBlockVarCopyInits - not __block var");
1277  BlockVarCopyInits[VD] = Init;
1278}
1279
1280/// \brief Allocate an uninitialized TypeSourceInfo.
1281///
1282/// The caller should initialize the memory held by TypeSourceInfo using
1283/// the TypeLoc wrappers.
1284///
1285/// \param T the type that will be the basis for type source info. This type
1286/// should refer to how the declarator was written in source code, not to
1287/// what type semantic analysis resolved the declarator to.
1288TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1289                                                 unsigned DataSize) const {
1290  if (!DataSize)
1291    DataSize = TypeLoc::getFullDataSizeForType(T);
1292  else
1293    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1294           "incorrect data size provided to CreateTypeSourceInfo!");
1295
1296  TypeSourceInfo *TInfo =
1297    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1298  new (TInfo) TypeSourceInfo(T);
1299  return TInfo;
1300}
1301
1302TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1303                                                     SourceLocation L) const {
1304  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1305  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
1306  return DI;
1307}
1308
1309const ASTRecordLayout &
1310ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
1311  return getObjCLayout(D, 0);
1312}
1313
1314const ASTRecordLayout &
1315ASTContext::getASTObjCImplementationLayout(
1316                                        const ObjCImplementationDecl *D) const {
1317  return getObjCLayout(D->getClassInterface(), D);
1318}
1319
1320//===----------------------------------------------------------------------===//
1321//                   Type creation/memoization methods
1322//===----------------------------------------------------------------------===//
1323
1324QualType
1325ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
1326  unsigned fastQuals = quals.getFastQualifiers();
1327  quals.removeFastQualifiers();
1328
1329  // Check if we've already instantiated this type.
1330  llvm::FoldingSetNodeID ID;
1331  ExtQuals::Profile(ID, baseType, quals);
1332  void *insertPos = 0;
1333  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
1334    assert(eq->getQualifiers() == quals);
1335    return QualType(eq, fastQuals);
1336  }
1337
1338  // If the base type is not canonical, make the appropriate canonical type.
1339  QualType canon;
1340  if (!baseType->isCanonicalUnqualified()) {
1341    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
1342    canonSplit.second.addConsistentQualifiers(quals);
1343    canon = getExtQualType(canonSplit.first, canonSplit.second);
1344
1345    // Re-find the insert position.
1346    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
1347  }
1348
1349  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
1350  ExtQualNodes.InsertNode(eq, insertPos);
1351  return QualType(eq, fastQuals);
1352}
1353
1354QualType
1355ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
1356  QualType CanT = getCanonicalType(T);
1357  if (CanT.getAddressSpace() == AddressSpace)
1358    return T;
1359
1360  // If we are composing extended qualifiers together, merge together
1361  // into one ExtQuals node.
1362  QualifierCollector Quals;
1363  const Type *TypeNode = Quals.strip(T);
1364
1365  // If this type already has an address space specified, it cannot get
1366  // another one.
1367  assert(!Quals.hasAddressSpace() &&
1368         "Type cannot be in multiple addr spaces!");
1369  Quals.addAddressSpace(AddressSpace);
1370
1371  return getExtQualType(TypeNode, Quals);
1372}
1373
1374QualType ASTContext::getObjCGCQualType(QualType T,
1375                                       Qualifiers::GC GCAttr) const {
1376  QualType CanT = getCanonicalType(T);
1377  if (CanT.getObjCGCAttr() == GCAttr)
1378    return T;
1379
1380  if (const PointerType *ptr = T->getAs<PointerType>()) {
1381    QualType Pointee = ptr->getPointeeType();
1382    if (Pointee->isAnyPointerType()) {
1383      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1384      return getPointerType(ResultType);
1385    }
1386  }
1387
1388  // If we are composing extended qualifiers together, merge together
1389  // into one ExtQuals node.
1390  QualifierCollector Quals;
1391  const Type *TypeNode = Quals.strip(T);
1392
1393  // If this type already has an ObjCGC specified, it cannot get
1394  // another one.
1395  assert(!Quals.hasObjCGCAttr() &&
1396         "Type cannot have multiple ObjCGCs!");
1397  Quals.addObjCGCAttr(GCAttr);
1398
1399  return getExtQualType(TypeNode, Quals);
1400}
1401
1402const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
1403                                                   FunctionType::ExtInfo Info) {
1404  if (T->getExtInfo() == Info)
1405    return T;
1406
1407  QualType Result;
1408  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
1409    Result = getFunctionNoProtoType(FNPT->getResultType(), Info);
1410  } else {
1411    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
1412    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
1413    EPI.ExtInfo = Info;
1414    Result = getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1415                             FPT->getNumArgs(), EPI);
1416  }
1417
1418  return cast<FunctionType>(Result.getTypePtr());
1419}
1420
1421/// getComplexType - Return the uniqued reference to the type for a complex
1422/// number with the specified element type.
1423QualType ASTContext::getComplexType(QualType T) const {
1424  // Unique pointers, to guarantee there is only one pointer of a particular
1425  // structure.
1426  llvm::FoldingSetNodeID ID;
1427  ComplexType::Profile(ID, T);
1428
1429  void *InsertPos = 0;
1430  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1431    return QualType(CT, 0);
1432
1433  // If the pointee type isn't canonical, this won't be a canonical type either,
1434  // so fill in the canonical type field.
1435  QualType Canonical;
1436  if (!T.isCanonical()) {
1437    Canonical = getComplexType(getCanonicalType(T));
1438
1439    // Get the new insert position for the node we care about.
1440    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1441    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1442  }
1443  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1444  Types.push_back(New);
1445  ComplexTypes.InsertNode(New, InsertPos);
1446  return QualType(New, 0);
1447}
1448
1449/// getPointerType - Return the uniqued reference to the type for a pointer to
1450/// the specified type.
1451QualType ASTContext::getPointerType(QualType T) const {
1452  // Unique pointers, to guarantee there is only one pointer of a particular
1453  // structure.
1454  llvm::FoldingSetNodeID ID;
1455  PointerType::Profile(ID, T);
1456
1457  void *InsertPos = 0;
1458  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1459    return QualType(PT, 0);
1460
1461  // If the pointee type isn't canonical, this won't be a canonical type either,
1462  // so fill in the canonical type field.
1463  QualType Canonical;
1464  if (!T.isCanonical()) {
1465    Canonical = getPointerType(getCanonicalType(T));
1466
1467    // Get the new insert position for the node we care about.
1468    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1469    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1470  }
1471  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1472  Types.push_back(New);
1473  PointerTypes.InsertNode(New, InsertPos);
1474  return QualType(New, 0);
1475}
1476
1477/// getBlockPointerType - Return the uniqued reference to the type for
1478/// a pointer to the specified block.
1479QualType ASTContext::getBlockPointerType(QualType T) const {
1480  assert(T->isFunctionType() && "block of function types only");
1481  // Unique pointers, to guarantee there is only one block of a particular
1482  // structure.
1483  llvm::FoldingSetNodeID ID;
1484  BlockPointerType::Profile(ID, T);
1485
1486  void *InsertPos = 0;
1487  if (BlockPointerType *PT =
1488        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1489    return QualType(PT, 0);
1490
1491  // If the block pointee type isn't canonical, this won't be a canonical
1492  // type either so fill in the canonical type field.
1493  QualType Canonical;
1494  if (!T.isCanonical()) {
1495    Canonical = getBlockPointerType(getCanonicalType(T));
1496
1497    // Get the new insert position for the node we care about.
1498    BlockPointerType *NewIP =
1499      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1500    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1501  }
1502  BlockPointerType *New
1503    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1504  Types.push_back(New);
1505  BlockPointerTypes.InsertNode(New, InsertPos);
1506  return QualType(New, 0);
1507}
1508
1509/// getLValueReferenceType - Return the uniqued reference to the type for an
1510/// lvalue reference to the specified type.
1511QualType
1512ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
1513  assert(getCanonicalType(T) != OverloadTy &&
1514         "Unresolved overloaded function type");
1515
1516  // Unique pointers, to guarantee there is only one pointer of a particular
1517  // structure.
1518  llvm::FoldingSetNodeID ID;
1519  ReferenceType::Profile(ID, T, SpelledAsLValue);
1520
1521  void *InsertPos = 0;
1522  if (LValueReferenceType *RT =
1523        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1524    return QualType(RT, 0);
1525
1526  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1527
1528  // If the referencee type isn't canonical, this won't be a canonical type
1529  // either, so fill in the canonical type field.
1530  QualType Canonical;
1531  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1532    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1533    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1534
1535    // Get the new insert position for the node we care about.
1536    LValueReferenceType *NewIP =
1537      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1538    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1539  }
1540
1541  LValueReferenceType *New
1542    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1543                                                     SpelledAsLValue);
1544  Types.push_back(New);
1545  LValueReferenceTypes.InsertNode(New, InsertPos);
1546
1547  return QualType(New, 0);
1548}
1549
1550/// getRValueReferenceType - Return the uniqued reference to the type for an
1551/// rvalue reference to the specified type.
1552QualType ASTContext::getRValueReferenceType(QualType T) const {
1553  // Unique pointers, to guarantee there is only one pointer of a particular
1554  // structure.
1555  llvm::FoldingSetNodeID ID;
1556  ReferenceType::Profile(ID, T, false);
1557
1558  void *InsertPos = 0;
1559  if (RValueReferenceType *RT =
1560        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1561    return QualType(RT, 0);
1562
1563  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1564
1565  // If the referencee type isn't canonical, this won't be a canonical type
1566  // either, so fill in the canonical type field.
1567  QualType Canonical;
1568  if (InnerRef || !T.isCanonical()) {
1569    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1570    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1571
1572    // Get the new insert position for the node we care about.
1573    RValueReferenceType *NewIP =
1574      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1575    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1576  }
1577
1578  RValueReferenceType *New
1579    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1580  Types.push_back(New);
1581  RValueReferenceTypes.InsertNode(New, InsertPos);
1582  return QualType(New, 0);
1583}
1584
1585/// getMemberPointerType - Return the uniqued reference to the type for a
1586/// member pointer to the specified type, in the specified class.
1587QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
1588  // Unique pointers, to guarantee there is only one pointer of a particular
1589  // structure.
1590  llvm::FoldingSetNodeID ID;
1591  MemberPointerType::Profile(ID, T, Cls);
1592
1593  void *InsertPos = 0;
1594  if (MemberPointerType *PT =
1595      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1596    return QualType(PT, 0);
1597
1598  // If the pointee or class type isn't canonical, this won't be a canonical
1599  // type either, so fill in the canonical type field.
1600  QualType Canonical;
1601  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1602    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1603
1604    // Get the new insert position for the node we care about.
1605    MemberPointerType *NewIP =
1606      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1607    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1608  }
1609  MemberPointerType *New
1610    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1611  Types.push_back(New);
1612  MemberPointerTypes.InsertNode(New, InsertPos);
1613  return QualType(New, 0);
1614}
1615
1616/// getConstantArrayType - Return the unique reference to the type for an
1617/// array of the specified element type.
1618QualType ASTContext::getConstantArrayType(QualType EltTy,
1619                                          const llvm::APInt &ArySizeIn,
1620                                          ArrayType::ArraySizeModifier ASM,
1621                                          unsigned IndexTypeQuals) const {
1622  assert((EltTy->isDependentType() ||
1623          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1624         "Constant array of VLAs is illegal!");
1625
1626  // Convert the array size into a canonical width matching the pointer size for
1627  // the target.
1628  llvm::APInt ArySize(ArySizeIn);
1629  ArySize =
1630    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
1631
1632  llvm::FoldingSetNodeID ID;
1633  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
1634
1635  void *InsertPos = 0;
1636  if (ConstantArrayType *ATP =
1637      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1638    return QualType(ATP, 0);
1639
1640  // If the element type isn't canonical or has qualifiers, this won't
1641  // be a canonical type either, so fill in the canonical type field.
1642  QualType Canon;
1643  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1644    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1645    Canon = getConstantArrayType(QualType(canonSplit.first, 0), ArySize,
1646                                 ASM, IndexTypeQuals);
1647    Canon = getQualifiedType(Canon, canonSplit.second);
1648
1649    // Get the new insert position for the node we care about.
1650    ConstantArrayType *NewIP =
1651      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1652    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1653  }
1654
1655  ConstantArrayType *New = new(*this,TypeAlignment)
1656    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
1657  ConstantArrayTypes.InsertNode(New, InsertPos);
1658  Types.push_back(New);
1659  return QualType(New, 0);
1660}
1661
1662/// getVariableArrayDecayedType - Turns the given type, which may be
1663/// variably-modified, into the corresponding type with all the known
1664/// sizes replaced with [*].
1665QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
1666  // Vastly most common case.
1667  if (!type->isVariablyModifiedType()) return type;
1668
1669  QualType result;
1670
1671  SplitQualType split = type.getSplitDesugaredType();
1672  const Type *ty = split.first;
1673  switch (ty->getTypeClass()) {
1674#define TYPE(Class, Base)
1675#define ABSTRACT_TYPE(Class, Base)
1676#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
1677#include "clang/AST/TypeNodes.def"
1678    llvm_unreachable("didn't desugar past all non-canonical types?");
1679
1680  // These types should never be variably-modified.
1681  case Type::Builtin:
1682  case Type::Complex:
1683  case Type::Vector:
1684  case Type::ExtVector:
1685  case Type::DependentSizedExtVector:
1686  case Type::ObjCObject:
1687  case Type::ObjCInterface:
1688  case Type::ObjCObjectPointer:
1689  case Type::Record:
1690  case Type::Enum:
1691  case Type::UnresolvedUsing:
1692  case Type::TypeOfExpr:
1693  case Type::TypeOf:
1694  case Type::Decltype:
1695  case Type::UnaryTransform:
1696  case Type::DependentName:
1697  case Type::InjectedClassName:
1698  case Type::TemplateSpecialization:
1699  case Type::DependentTemplateSpecialization:
1700  case Type::TemplateTypeParm:
1701  case Type::SubstTemplateTypeParmPack:
1702  case Type::Auto:
1703  case Type::PackExpansion:
1704    llvm_unreachable("type should never be variably-modified");
1705
1706  // These types can be variably-modified but should never need to
1707  // further decay.
1708  case Type::FunctionNoProto:
1709  case Type::FunctionProto:
1710  case Type::BlockPointer:
1711  case Type::MemberPointer:
1712    return type;
1713
1714  // These types can be variably-modified.  All these modifications
1715  // preserve structure except as noted by comments.
1716  // TODO: if we ever care about optimizing VLAs, there are no-op
1717  // optimizations available here.
1718  case Type::Pointer:
1719    result = getPointerType(getVariableArrayDecayedType(
1720                              cast<PointerType>(ty)->getPointeeType()));
1721    break;
1722
1723  case Type::LValueReference: {
1724    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
1725    result = getLValueReferenceType(
1726                 getVariableArrayDecayedType(lv->getPointeeType()),
1727                                    lv->isSpelledAsLValue());
1728    break;
1729  }
1730
1731  case Type::RValueReference: {
1732    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
1733    result = getRValueReferenceType(
1734                 getVariableArrayDecayedType(lv->getPointeeType()));
1735    break;
1736  }
1737
1738  case Type::Atomic: {
1739    const AtomicType *at = cast<AtomicType>(ty);
1740    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
1741    break;
1742  }
1743
1744  case Type::ConstantArray: {
1745    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
1746    result = getConstantArrayType(
1747                 getVariableArrayDecayedType(cat->getElementType()),
1748                                  cat->getSize(),
1749                                  cat->getSizeModifier(),
1750                                  cat->getIndexTypeCVRQualifiers());
1751    break;
1752  }
1753
1754  case Type::DependentSizedArray: {
1755    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
1756    result = getDependentSizedArrayType(
1757                 getVariableArrayDecayedType(dat->getElementType()),
1758                                        dat->getSizeExpr(),
1759                                        dat->getSizeModifier(),
1760                                        dat->getIndexTypeCVRQualifiers(),
1761                                        dat->getBracketsRange());
1762    break;
1763  }
1764
1765  // Turn incomplete types into [*] types.
1766  case Type::IncompleteArray: {
1767    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
1768    result = getVariableArrayType(
1769                 getVariableArrayDecayedType(iat->getElementType()),
1770                                  /*size*/ 0,
1771                                  ArrayType::Normal,
1772                                  iat->getIndexTypeCVRQualifiers(),
1773                                  SourceRange());
1774    break;
1775  }
1776
1777  // Turn VLA types into [*] types.
1778  case Type::VariableArray: {
1779    const VariableArrayType *vat = cast<VariableArrayType>(ty);
1780    result = getVariableArrayType(
1781                 getVariableArrayDecayedType(vat->getElementType()),
1782                                  /*size*/ 0,
1783                                  ArrayType::Star,
1784                                  vat->getIndexTypeCVRQualifiers(),
1785                                  vat->getBracketsRange());
1786    break;
1787  }
1788  }
1789
1790  // Apply the top-level qualifiers from the original.
1791  return getQualifiedType(result, split.second);
1792}
1793
1794/// getVariableArrayType - Returns a non-unique reference to the type for a
1795/// variable array of the specified element type.
1796QualType ASTContext::getVariableArrayType(QualType EltTy,
1797                                          Expr *NumElts,
1798                                          ArrayType::ArraySizeModifier ASM,
1799                                          unsigned IndexTypeQuals,
1800                                          SourceRange Brackets) const {
1801  // Since we don't unique expressions, it isn't possible to unique VLA's
1802  // that have an expression provided for their size.
1803  QualType Canon;
1804
1805  // Be sure to pull qualifiers off the element type.
1806  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
1807    SplitQualType canonSplit = getCanonicalType(EltTy).split();
1808    Canon = getVariableArrayType(QualType(canonSplit.first, 0), NumElts, ASM,
1809                                 IndexTypeQuals, Brackets);
1810    Canon = getQualifiedType(Canon, canonSplit.second);
1811  }
1812
1813  VariableArrayType *New = new(*this, TypeAlignment)
1814    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
1815
1816  VariableArrayTypes.push_back(New);
1817  Types.push_back(New);
1818  return QualType(New, 0);
1819}
1820
1821/// getDependentSizedArrayType - Returns a non-unique reference to
1822/// the type for a dependently-sized array of the specified element
1823/// type.
1824QualType ASTContext::getDependentSizedArrayType(QualType elementType,
1825                                                Expr *numElements,
1826                                                ArrayType::ArraySizeModifier ASM,
1827                                                unsigned elementTypeQuals,
1828                                                SourceRange brackets) const {
1829  assert((!numElements || numElements->isTypeDependent() ||
1830          numElements->isValueDependent()) &&
1831         "Size must be type- or value-dependent!");
1832
1833  // Dependently-sized array types that do not have a specified number
1834  // of elements will have their sizes deduced from a dependent
1835  // initializer.  We do no canonicalization here at all, which is okay
1836  // because they can't be used in most locations.
1837  if (!numElements) {
1838    DependentSizedArrayType *newType
1839      = new (*this, TypeAlignment)
1840          DependentSizedArrayType(*this, elementType, QualType(),
1841                                  numElements, ASM, elementTypeQuals,
1842                                  brackets);
1843    Types.push_back(newType);
1844    return QualType(newType, 0);
1845  }
1846
1847  // Otherwise, we actually build a new type every time, but we
1848  // also build a canonical type.
1849
1850  SplitQualType canonElementType = getCanonicalType(elementType).split();
1851
1852  void *insertPos = 0;
1853  llvm::FoldingSetNodeID ID;
1854  DependentSizedArrayType::Profile(ID, *this,
1855                                   QualType(canonElementType.first, 0),
1856                                   ASM, elementTypeQuals, numElements);
1857
1858  // Look for an existing type with these properties.
1859  DependentSizedArrayType *canonTy =
1860    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1861
1862  // If we don't have one, build one.
1863  if (!canonTy) {
1864    canonTy = new (*this, TypeAlignment)
1865      DependentSizedArrayType(*this, QualType(canonElementType.first, 0),
1866                              QualType(), numElements, ASM, elementTypeQuals,
1867                              brackets);
1868    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
1869    Types.push_back(canonTy);
1870  }
1871
1872  // Apply qualifiers from the element type to the array.
1873  QualType canon = getQualifiedType(QualType(canonTy,0),
1874                                    canonElementType.second);
1875
1876  // If we didn't need extra canonicalization for the element type,
1877  // then just use that as our result.
1878  if (QualType(canonElementType.first, 0) == elementType)
1879    return canon;
1880
1881  // Otherwise, we need to build a type which follows the spelling
1882  // of the element type.
1883  DependentSizedArrayType *sugaredType
1884    = new (*this, TypeAlignment)
1885        DependentSizedArrayType(*this, elementType, canon, numElements,
1886                                ASM, elementTypeQuals, brackets);
1887  Types.push_back(sugaredType);
1888  return QualType(sugaredType, 0);
1889}
1890
1891QualType ASTContext::getIncompleteArrayType(QualType elementType,
1892                                            ArrayType::ArraySizeModifier ASM,
1893                                            unsigned elementTypeQuals) const {
1894  llvm::FoldingSetNodeID ID;
1895  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
1896
1897  void *insertPos = 0;
1898  if (IncompleteArrayType *iat =
1899       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
1900    return QualType(iat, 0);
1901
1902  // If the element type isn't canonical, this won't be a canonical type
1903  // either, so fill in the canonical type field.  We also have to pull
1904  // qualifiers off the element type.
1905  QualType canon;
1906
1907  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
1908    SplitQualType canonSplit = getCanonicalType(elementType).split();
1909    canon = getIncompleteArrayType(QualType(canonSplit.first, 0),
1910                                   ASM, elementTypeQuals);
1911    canon = getQualifiedType(canon, canonSplit.second);
1912
1913    // Get the new insert position for the node we care about.
1914    IncompleteArrayType *existing =
1915      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
1916    assert(!existing && "Shouldn't be in the map!"); (void) existing;
1917  }
1918
1919  IncompleteArrayType *newType = new (*this, TypeAlignment)
1920    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
1921
1922  IncompleteArrayTypes.InsertNode(newType, insertPos);
1923  Types.push_back(newType);
1924  return QualType(newType, 0);
1925}
1926
1927/// getVectorType - Return the unique reference to a vector type of
1928/// the specified element type and size. VectorType must be a built-in type.
1929QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1930                                   VectorType::VectorKind VecKind) const {
1931  assert(vecType->isBuiltinType());
1932
1933  // Check if we've already instantiated a vector of this type.
1934  llvm::FoldingSetNodeID ID;
1935  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
1936
1937  void *InsertPos = 0;
1938  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1939    return QualType(VTP, 0);
1940
1941  // If the element type isn't canonical, this won't be a canonical type either,
1942  // so fill in the canonical type field.
1943  QualType Canonical;
1944  if (!vecType.isCanonical()) {
1945    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
1946
1947    // Get the new insert position for the node we care about.
1948    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1949    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1950  }
1951  VectorType *New = new (*this, TypeAlignment)
1952    VectorType(vecType, NumElts, Canonical, VecKind);
1953  VectorTypes.InsertNode(New, InsertPos);
1954  Types.push_back(New);
1955  return QualType(New, 0);
1956}
1957
1958/// getExtVectorType - Return the unique reference to an extended vector type of
1959/// the specified element type and size. VectorType must be a built-in type.
1960QualType
1961ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
1962  assert(vecType->isBuiltinType() || vecType->isDependentType());
1963
1964  // Check if we've already instantiated a vector of this type.
1965  llvm::FoldingSetNodeID ID;
1966  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1967                      VectorType::GenericVector);
1968  void *InsertPos = 0;
1969  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1970    return QualType(VTP, 0);
1971
1972  // If the element type isn't canonical, this won't be a canonical type either,
1973  // so fill in the canonical type field.
1974  QualType Canonical;
1975  if (!vecType.isCanonical()) {
1976    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
1977
1978    // Get the new insert position for the node we care about.
1979    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1980    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1981  }
1982  ExtVectorType *New = new (*this, TypeAlignment)
1983    ExtVectorType(vecType, NumElts, Canonical);
1984  VectorTypes.InsertNode(New, InsertPos);
1985  Types.push_back(New);
1986  return QualType(New, 0);
1987}
1988
1989QualType
1990ASTContext::getDependentSizedExtVectorType(QualType vecType,
1991                                           Expr *SizeExpr,
1992                                           SourceLocation AttrLoc) const {
1993  llvm::FoldingSetNodeID ID;
1994  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
1995                                       SizeExpr);
1996
1997  void *InsertPos = 0;
1998  DependentSizedExtVectorType *Canon
1999    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2000  DependentSizedExtVectorType *New;
2001  if (Canon) {
2002    // We already have a canonical version of this array type; use it as
2003    // the canonical type for a newly-built type.
2004    New = new (*this, TypeAlignment)
2005      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
2006                                  SizeExpr, AttrLoc);
2007  } else {
2008    QualType CanonVecTy = getCanonicalType(vecType);
2009    if (CanonVecTy == vecType) {
2010      New = new (*this, TypeAlignment)
2011        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
2012                                    AttrLoc);
2013
2014      DependentSizedExtVectorType *CanonCheck
2015        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2016      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
2017      (void)CanonCheck;
2018      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
2019    } else {
2020      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
2021                                                      SourceLocation());
2022      New = new (*this, TypeAlignment)
2023        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2024    }
2025  }
2026
2027  Types.push_back(New);
2028  return QualType(New, 0);
2029}
2030
2031/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
2032///
2033QualType
2034ASTContext::getFunctionNoProtoType(QualType ResultTy,
2035                                   const FunctionType::ExtInfo &Info) const {
2036  const CallingConv DefaultCC = Info.getCC();
2037  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2038                               CC_X86StdCall : DefaultCC;
2039  // Unique functions, to guarantee there is only one function of a particular
2040  // structure.
2041  llvm::FoldingSetNodeID ID;
2042  FunctionNoProtoType::Profile(ID, ResultTy, Info);
2043
2044  void *InsertPos = 0;
2045  if (FunctionNoProtoType *FT =
2046        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2047    return QualType(FT, 0);
2048
2049  QualType Canonical;
2050  if (!ResultTy.isCanonical() ||
2051      getCanonicalCallConv(CallConv) != CallConv) {
2052    Canonical =
2053      getFunctionNoProtoType(getCanonicalType(ResultTy),
2054                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
2055
2056    // Get the new insert position for the node we care about.
2057    FunctionNoProtoType *NewIP =
2058      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2059    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2060  }
2061
2062  FunctionProtoType::ExtInfo newInfo = Info.withCallingConv(CallConv);
2063  FunctionNoProtoType *New = new (*this, TypeAlignment)
2064    FunctionNoProtoType(ResultTy, Canonical, newInfo);
2065  Types.push_back(New);
2066  FunctionNoProtoTypes.InsertNode(New, InsertPos);
2067  return QualType(New, 0);
2068}
2069
2070/// getFunctionType - Return a normal function type with a typed argument
2071/// list.  isVariadic indicates whether the argument list includes '...'.
2072QualType
2073ASTContext::getFunctionType(QualType ResultTy,
2074                            const QualType *ArgArray, unsigned NumArgs,
2075                            const FunctionProtoType::ExtProtoInfo &EPI) const {
2076  // Unique functions, to guarantee there is only one function of a particular
2077  // structure.
2078  llvm::FoldingSetNodeID ID;
2079  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, EPI, *this);
2080
2081  void *InsertPos = 0;
2082  if (FunctionProtoType *FTP =
2083        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2084    return QualType(FTP, 0);
2085
2086  // Determine whether the type being created is already canonical or not.
2087  bool isCanonical= EPI.ExceptionSpecType == EST_None && ResultTy.isCanonical();
2088  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
2089    if (!ArgArray[i].isCanonicalAsParam())
2090      isCanonical = false;
2091
2092  const CallingConv DefaultCC = EPI.ExtInfo.getCC();
2093  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2094                               CC_X86StdCall : DefaultCC;
2095
2096  // If this type isn't canonical, get the canonical version of it.
2097  // The exception spec is not part of the canonical type.
2098  QualType Canonical;
2099  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
2100    SmallVector<QualType, 16> CanonicalArgs;
2101    CanonicalArgs.reserve(NumArgs);
2102    for (unsigned i = 0; i != NumArgs; ++i)
2103      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
2104
2105    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
2106    CanonicalEPI.ExceptionSpecType = EST_None;
2107    CanonicalEPI.NumExceptions = 0;
2108    CanonicalEPI.ExtInfo
2109      = CanonicalEPI.ExtInfo.withCallingConv(getCanonicalCallConv(CallConv));
2110
2111    Canonical = getFunctionType(getCanonicalType(ResultTy),
2112                                CanonicalArgs.data(), NumArgs,
2113                                CanonicalEPI);
2114
2115    // Get the new insert position for the node we care about.
2116    FunctionProtoType *NewIP =
2117      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2118    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2119  }
2120
2121  // FunctionProtoType objects are allocated with extra bytes after
2122  // them for three variable size arrays at the end:
2123  //  - parameter types
2124  //  - exception types
2125  //  - consumed-arguments flags
2126  // Instead of the exception types, there could be a noexcept
2127  // expression.
2128  size_t Size = sizeof(FunctionProtoType) +
2129                NumArgs * sizeof(QualType);
2130  if (EPI.ExceptionSpecType == EST_Dynamic)
2131    Size += EPI.NumExceptions * sizeof(QualType);
2132  else if (EPI.ExceptionSpecType == EST_ComputedNoexcept) {
2133    Size += sizeof(Expr*);
2134  }
2135  if (EPI.ConsumedArguments)
2136    Size += NumArgs * sizeof(bool);
2137
2138  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
2139  FunctionProtoType::ExtProtoInfo newEPI = EPI;
2140  newEPI.ExtInfo = EPI.ExtInfo.withCallingConv(CallConv);
2141  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, Canonical, newEPI);
2142  Types.push_back(FTP);
2143  FunctionProtoTypes.InsertNode(FTP, InsertPos);
2144  return QualType(FTP, 0);
2145}
2146
2147#ifndef NDEBUG
2148static bool NeedsInjectedClassNameType(const RecordDecl *D) {
2149  if (!isa<CXXRecordDecl>(D)) return false;
2150  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
2151  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
2152    return true;
2153  if (RD->getDescribedClassTemplate() &&
2154      !isa<ClassTemplateSpecializationDecl>(RD))
2155    return true;
2156  return false;
2157}
2158#endif
2159
2160/// getInjectedClassNameType - Return the unique reference to the
2161/// injected class name type for the specified templated declaration.
2162QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
2163                                              QualType TST) const {
2164  assert(NeedsInjectedClassNameType(Decl));
2165  if (Decl->TypeForDecl) {
2166    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2167  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDeclaration()) {
2168    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
2169    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2170    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2171  } else {
2172    Type *newType =
2173      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
2174    Decl->TypeForDecl = newType;
2175    Types.push_back(newType);
2176  }
2177  return QualType(Decl->TypeForDecl, 0);
2178}
2179
2180/// getTypeDeclType - Return the unique reference to the type for the
2181/// specified type declaration.
2182QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) const {
2183  assert(Decl && "Passed null for Decl param");
2184  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
2185
2186  if (const TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Decl))
2187    return getTypedefType(Typedef);
2188
2189  assert(!isa<TemplateTypeParmDecl>(Decl) &&
2190         "Template type parameter types are always available.");
2191
2192  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
2193    assert(!Record->getPreviousDeclaration() &&
2194           "struct/union has previous declaration");
2195    assert(!NeedsInjectedClassNameType(Record));
2196    return getRecordType(Record);
2197  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
2198    assert(!Enum->getPreviousDeclaration() &&
2199           "enum has previous declaration");
2200    return getEnumType(Enum);
2201  } else if (const UnresolvedUsingTypenameDecl *Using =
2202               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
2203    Type *newType = new (*this, TypeAlignment) UnresolvedUsingType(Using);
2204    Decl->TypeForDecl = newType;
2205    Types.push_back(newType);
2206  } else
2207    llvm_unreachable("TypeDecl without a type?");
2208
2209  return QualType(Decl->TypeForDecl, 0);
2210}
2211
2212/// getTypedefType - Return the unique reference to the type for the
2213/// specified typedef name decl.
2214QualType
2215ASTContext::getTypedefType(const TypedefNameDecl *Decl,
2216                           QualType Canonical) const {
2217  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2218
2219  if (Canonical.isNull())
2220    Canonical = getCanonicalType(Decl->getUnderlyingType());
2221  TypedefType *newType = new(*this, TypeAlignment)
2222    TypedefType(Type::Typedef, Decl, Canonical);
2223  Decl->TypeForDecl = newType;
2224  Types.push_back(newType);
2225  return QualType(newType, 0);
2226}
2227
2228QualType ASTContext::getRecordType(const RecordDecl *Decl) const {
2229  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2230
2231  if (const RecordDecl *PrevDecl = Decl->getPreviousDeclaration())
2232    if (PrevDecl->TypeForDecl)
2233      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2234
2235  RecordType *newType = new (*this, TypeAlignment) RecordType(Decl);
2236  Decl->TypeForDecl = newType;
2237  Types.push_back(newType);
2238  return QualType(newType, 0);
2239}
2240
2241QualType ASTContext::getEnumType(const EnumDecl *Decl) const {
2242  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2243
2244  if (const EnumDecl *PrevDecl = Decl->getPreviousDeclaration())
2245    if (PrevDecl->TypeForDecl)
2246      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2247
2248  EnumType *newType = new (*this, TypeAlignment) EnumType(Decl);
2249  Decl->TypeForDecl = newType;
2250  Types.push_back(newType);
2251  return QualType(newType, 0);
2252}
2253
2254QualType ASTContext::getAttributedType(AttributedType::Kind attrKind,
2255                                       QualType modifiedType,
2256                                       QualType equivalentType) {
2257  llvm::FoldingSetNodeID id;
2258  AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
2259
2260  void *insertPos = 0;
2261  AttributedType *type = AttributedTypes.FindNodeOrInsertPos(id, insertPos);
2262  if (type) return QualType(type, 0);
2263
2264  QualType canon = getCanonicalType(equivalentType);
2265  type = new (*this, TypeAlignment)
2266           AttributedType(canon, attrKind, modifiedType, equivalentType);
2267
2268  Types.push_back(type);
2269  AttributedTypes.InsertNode(type, insertPos);
2270
2271  return QualType(type, 0);
2272}
2273
2274
2275/// \brief Retrieve a substitution-result type.
2276QualType
2277ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
2278                                         QualType Replacement) const {
2279  assert(Replacement.isCanonical()
2280         && "replacement types must always be canonical");
2281
2282  llvm::FoldingSetNodeID ID;
2283  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
2284  void *InsertPos = 0;
2285  SubstTemplateTypeParmType *SubstParm
2286    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2287
2288  if (!SubstParm) {
2289    SubstParm = new (*this, TypeAlignment)
2290      SubstTemplateTypeParmType(Parm, Replacement);
2291    Types.push_back(SubstParm);
2292    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2293  }
2294
2295  return QualType(SubstParm, 0);
2296}
2297
2298/// \brief Retrieve a
2299QualType ASTContext::getSubstTemplateTypeParmPackType(
2300                                          const TemplateTypeParmType *Parm,
2301                                              const TemplateArgument &ArgPack) {
2302#ifndef NDEBUG
2303  for (TemplateArgument::pack_iterator P = ArgPack.pack_begin(),
2304                                    PEnd = ArgPack.pack_end();
2305       P != PEnd; ++P) {
2306    assert(P->getKind() == TemplateArgument::Type &&"Pack contains a non-type");
2307    assert(P->getAsType().isCanonical() && "Pack contains non-canonical type");
2308  }
2309#endif
2310
2311  llvm::FoldingSetNodeID ID;
2312  SubstTemplateTypeParmPackType::Profile(ID, Parm, ArgPack);
2313  void *InsertPos = 0;
2314  if (SubstTemplateTypeParmPackType *SubstParm
2315        = SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos))
2316    return QualType(SubstParm, 0);
2317
2318  QualType Canon;
2319  if (!Parm->isCanonicalUnqualified()) {
2320    Canon = getCanonicalType(QualType(Parm, 0));
2321    Canon = getSubstTemplateTypeParmPackType(cast<TemplateTypeParmType>(Canon),
2322                                             ArgPack);
2323    SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos);
2324  }
2325
2326  SubstTemplateTypeParmPackType *SubstParm
2327    = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
2328                                                               ArgPack);
2329  Types.push_back(SubstParm);
2330  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2331  return QualType(SubstParm, 0);
2332}
2333
2334/// \brief Retrieve the template type parameter type for a template
2335/// parameter or parameter pack with the given depth, index, and (optionally)
2336/// name.
2337QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
2338                                             bool ParameterPack,
2339                                             TemplateTypeParmDecl *TTPDecl) const {
2340  llvm::FoldingSetNodeID ID;
2341  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, TTPDecl);
2342  void *InsertPos = 0;
2343  TemplateTypeParmType *TypeParm
2344    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2345
2346  if (TypeParm)
2347    return QualType(TypeParm, 0);
2348
2349  if (TTPDecl) {
2350    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
2351    TypeParm = new (*this, TypeAlignment) TemplateTypeParmType(TTPDecl, Canon);
2352
2353    TemplateTypeParmType *TypeCheck
2354      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2355    assert(!TypeCheck && "Template type parameter canonical type broken");
2356    (void)TypeCheck;
2357  } else
2358    TypeParm = new (*this, TypeAlignment)
2359      TemplateTypeParmType(Depth, Index, ParameterPack);
2360
2361  Types.push_back(TypeParm);
2362  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
2363
2364  return QualType(TypeParm, 0);
2365}
2366
2367TypeSourceInfo *
2368ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
2369                                              SourceLocation NameLoc,
2370                                        const TemplateArgumentListInfo &Args,
2371                                              QualType Underlying) const {
2372  assert(!Name.getAsDependentTemplateName() &&
2373         "No dependent template names here!");
2374  QualType TST = getTemplateSpecializationType(Name, Args, Underlying);
2375
2376  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
2377  TemplateSpecializationTypeLoc TL
2378    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
2379  TL.setTemplateNameLoc(NameLoc);
2380  TL.setLAngleLoc(Args.getLAngleLoc());
2381  TL.setRAngleLoc(Args.getRAngleLoc());
2382  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
2383    TL.setArgLocInfo(i, Args[i].getLocInfo());
2384  return DI;
2385}
2386
2387QualType
2388ASTContext::getTemplateSpecializationType(TemplateName Template,
2389                                          const TemplateArgumentListInfo &Args,
2390                                          QualType Underlying) const {
2391  assert(!Template.getAsDependentTemplateName() &&
2392         "No dependent template names here!");
2393
2394  unsigned NumArgs = Args.size();
2395
2396  SmallVector<TemplateArgument, 4> ArgVec;
2397  ArgVec.reserve(NumArgs);
2398  for (unsigned i = 0; i != NumArgs; ++i)
2399    ArgVec.push_back(Args[i].getArgument());
2400
2401  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
2402                                       Underlying);
2403}
2404
2405QualType
2406ASTContext::getTemplateSpecializationType(TemplateName Template,
2407                                          const TemplateArgument *Args,
2408                                          unsigned NumArgs,
2409                                          QualType Underlying) const {
2410  assert(!Template.getAsDependentTemplateName() &&
2411         "No dependent template names here!");
2412  // Look through qualified template names.
2413  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2414    Template = TemplateName(QTN->getTemplateDecl());
2415
2416  bool isTypeAlias =
2417    Template.getAsTemplateDecl() &&
2418    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
2419
2420  QualType CanonType;
2421  if (!Underlying.isNull())
2422    CanonType = getCanonicalType(Underlying);
2423  else {
2424    assert(!isTypeAlias &&
2425           "Underlying type for template alias must be computed by caller");
2426    CanonType = getCanonicalTemplateSpecializationType(Template, Args,
2427                                                       NumArgs);
2428  }
2429
2430  // Allocate the (non-canonical) template specialization type, but don't
2431  // try to unique it: these types typically have location information that
2432  // we don't unique and don't want to lose.
2433  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
2434                       sizeof(TemplateArgument) * NumArgs +
2435                       (isTypeAlias ? sizeof(QualType) : 0),
2436                       TypeAlignment);
2437  TemplateSpecializationType *Spec
2438    = new (Mem) TemplateSpecializationType(Template,
2439                                           Args, NumArgs,
2440                                           CanonType,
2441                                         isTypeAlias ? Underlying : QualType());
2442
2443  Types.push_back(Spec);
2444  return QualType(Spec, 0);
2445}
2446
2447QualType
2448ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
2449                                                   const TemplateArgument *Args,
2450                                                   unsigned NumArgs) const {
2451  assert(!Template.getAsDependentTemplateName() &&
2452         "No dependent template names here!");
2453  assert((!Template.getAsTemplateDecl() ||
2454          !isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl())) &&
2455         "Underlying type for template alias must be computed by caller");
2456
2457  // Look through qualified template names.
2458  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2459    Template = TemplateName(QTN->getTemplateDecl());
2460
2461  // Build the canonical template specialization type.
2462  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
2463  SmallVector<TemplateArgument, 4> CanonArgs;
2464  CanonArgs.reserve(NumArgs);
2465  for (unsigned I = 0; I != NumArgs; ++I)
2466    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
2467
2468  // Determine whether this canonical template specialization type already
2469  // exists.
2470  llvm::FoldingSetNodeID ID;
2471  TemplateSpecializationType::Profile(ID, CanonTemplate,
2472                                      CanonArgs.data(), NumArgs, *this);
2473
2474  void *InsertPos = 0;
2475  TemplateSpecializationType *Spec
2476    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2477
2478  if (!Spec) {
2479    // Allocate a new canonical template specialization type.
2480    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2481                          sizeof(TemplateArgument) * NumArgs),
2482                         TypeAlignment);
2483    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
2484                                                CanonArgs.data(), NumArgs,
2485                                                QualType(), QualType());
2486    Types.push_back(Spec);
2487    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
2488  }
2489
2490  assert(Spec->isDependentType() &&
2491         "Non-dependent template-id type must have a canonical type");
2492  return QualType(Spec, 0);
2493}
2494
2495QualType
2496ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
2497                              NestedNameSpecifier *NNS,
2498                              QualType NamedType) const {
2499  llvm::FoldingSetNodeID ID;
2500  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2501
2502  void *InsertPos = 0;
2503  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2504  if (T)
2505    return QualType(T, 0);
2506
2507  QualType Canon = NamedType;
2508  if (!Canon.isCanonical()) {
2509    Canon = getCanonicalType(NamedType);
2510    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2511    assert(!CheckT && "Elaborated canonical type broken");
2512    (void)CheckT;
2513  }
2514
2515  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2516  Types.push_back(T);
2517  ElaboratedTypes.InsertNode(T, InsertPos);
2518  return QualType(T, 0);
2519}
2520
2521QualType
2522ASTContext::getParenType(QualType InnerType) const {
2523  llvm::FoldingSetNodeID ID;
2524  ParenType::Profile(ID, InnerType);
2525
2526  void *InsertPos = 0;
2527  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2528  if (T)
2529    return QualType(T, 0);
2530
2531  QualType Canon = InnerType;
2532  if (!Canon.isCanonical()) {
2533    Canon = getCanonicalType(InnerType);
2534    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2535    assert(!CheckT && "Paren canonical type broken");
2536    (void)CheckT;
2537  }
2538
2539  T = new (*this) ParenType(InnerType, Canon);
2540  Types.push_back(T);
2541  ParenTypes.InsertNode(T, InsertPos);
2542  return QualType(T, 0);
2543}
2544
2545QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2546                                          NestedNameSpecifier *NNS,
2547                                          const IdentifierInfo *Name,
2548                                          QualType Canon) const {
2549  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2550
2551  if (Canon.isNull()) {
2552    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2553    ElaboratedTypeKeyword CanonKeyword = Keyword;
2554    if (Keyword == ETK_None)
2555      CanonKeyword = ETK_Typename;
2556
2557    if (CanonNNS != NNS || CanonKeyword != Keyword)
2558      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2559  }
2560
2561  llvm::FoldingSetNodeID ID;
2562  DependentNameType::Profile(ID, Keyword, NNS, Name);
2563
2564  void *InsertPos = 0;
2565  DependentNameType *T
2566    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2567  if (T)
2568    return QualType(T, 0);
2569
2570  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2571  Types.push_back(T);
2572  DependentNameTypes.InsertNode(T, InsertPos);
2573  return QualType(T, 0);
2574}
2575
2576QualType
2577ASTContext::getDependentTemplateSpecializationType(
2578                                 ElaboratedTypeKeyword Keyword,
2579                                 NestedNameSpecifier *NNS,
2580                                 const IdentifierInfo *Name,
2581                                 const TemplateArgumentListInfo &Args) const {
2582  // TODO: avoid this copy
2583  SmallVector<TemplateArgument, 16> ArgCopy;
2584  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2585    ArgCopy.push_back(Args[I].getArgument());
2586  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2587                                                ArgCopy.size(),
2588                                                ArgCopy.data());
2589}
2590
2591QualType
2592ASTContext::getDependentTemplateSpecializationType(
2593                                 ElaboratedTypeKeyword Keyword,
2594                                 NestedNameSpecifier *NNS,
2595                                 const IdentifierInfo *Name,
2596                                 unsigned NumArgs,
2597                                 const TemplateArgument *Args) const {
2598  assert((!NNS || NNS->isDependent()) &&
2599         "nested-name-specifier must be dependent");
2600
2601  llvm::FoldingSetNodeID ID;
2602  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2603                                               Name, NumArgs, Args);
2604
2605  void *InsertPos = 0;
2606  DependentTemplateSpecializationType *T
2607    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2608  if (T)
2609    return QualType(T, 0);
2610
2611  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2612
2613  ElaboratedTypeKeyword CanonKeyword = Keyword;
2614  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2615
2616  bool AnyNonCanonArgs = false;
2617  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2618  for (unsigned I = 0; I != NumArgs; ++I) {
2619    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2620    if (!CanonArgs[I].structurallyEquals(Args[I]))
2621      AnyNonCanonArgs = true;
2622  }
2623
2624  QualType Canon;
2625  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2626    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2627                                                   Name, NumArgs,
2628                                                   CanonArgs.data());
2629
2630    // Find the insert position again.
2631    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2632  }
2633
2634  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2635                        sizeof(TemplateArgument) * NumArgs),
2636                       TypeAlignment);
2637  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2638                                                    Name, NumArgs, Args, Canon);
2639  Types.push_back(T);
2640  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2641  return QualType(T, 0);
2642}
2643
2644QualType ASTContext::getPackExpansionType(QualType Pattern,
2645                                      llvm::Optional<unsigned> NumExpansions) {
2646  llvm::FoldingSetNodeID ID;
2647  PackExpansionType::Profile(ID, Pattern, NumExpansions);
2648
2649  assert(Pattern->containsUnexpandedParameterPack() &&
2650         "Pack expansions must expand one or more parameter packs");
2651  void *InsertPos = 0;
2652  PackExpansionType *T
2653    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2654  if (T)
2655    return QualType(T, 0);
2656
2657  QualType Canon;
2658  if (!Pattern.isCanonical()) {
2659    Canon = getPackExpansionType(getCanonicalType(Pattern), NumExpansions);
2660
2661    // Find the insert position again.
2662    PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2663  }
2664
2665  T = new (*this) PackExpansionType(Pattern, Canon, NumExpansions);
2666  Types.push_back(T);
2667  PackExpansionTypes.InsertNode(T, InsertPos);
2668  return QualType(T, 0);
2669}
2670
2671/// CmpProtocolNames - Comparison predicate for sorting protocols
2672/// alphabetically.
2673static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2674                            const ObjCProtocolDecl *RHS) {
2675  return LHS->getDeclName() < RHS->getDeclName();
2676}
2677
2678static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2679                                unsigned NumProtocols) {
2680  if (NumProtocols == 0) return true;
2681
2682  for (unsigned i = 1; i != NumProtocols; ++i)
2683    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]))
2684      return false;
2685  return true;
2686}
2687
2688static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2689                                   unsigned &NumProtocols) {
2690  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2691
2692  // Sort protocols, keyed by name.
2693  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2694
2695  // Remove duplicates.
2696  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2697  NumProtocols = ProtocolsEnd-Protocols;
2698}
2699
2700QualType ASTContext::getObjCObjectType(QualType BaseType,
2701                                       ObjCProtocolDecl * const *Protocols,
2702                                       unsigned NumProtocols) const {
2703  // If the base type is an interface and there aren't any protocols
2704  // to add, then the interface type will do just fine.
2705  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2706    return BaseType;
2707
2708  // Look in the folding set for an existing type.
2709  llvm::FoldingSetNodeID ID;
2710  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2711  void *InsertPos = 0;
2712  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2713    return QualType(QT, 0);
2714
2715  // Build the canonical type, which has the canonical base type and
2716  // a sorted-and-uniqued list of protocols.
2717  QualType Canonical;
2718  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2719  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2720    if (!ProtocolsSorted) {
2721      SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2722                                                     Protocols + NumProtocols);
2723      unsigned UniqueCount = NumProtocols;
2724
2725      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2726      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2727                                    &Sorted[0], UniqueCount);
2728    } else {
2729      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2730                                    Protocols, NumProtocols);
2731    }
2732
2733    // Regenerate InsertPos.
2734    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2735  }
2736
2737  unsigned Size = sizeof(ObjCObjectTypeImpl);
2738  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2739  void *Mem = Allocate(Size, TypeAlignment);
2740  ObjCObjectTypeImpl *T =
2741    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2742
2743  Types.push_back(T);
2744  ObjCObjectTypes.InsertNode(T, InsertPos);
2745  return QualType(T, 0);
2746}
2747
2748/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2749/// the given object type.
2750QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
2751  llvm::FoldingSetNodeID ID;
2752  ObjCObjectPointerType::Profile(ID, ObjectT);
2753
2754  void *InsertPos = 0;
2755  if (ObjCObjectPointerType *QT =
2756              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2757    return QualType(QT, 0);
2758
2759  // Find the canonical object type.
2760  QualType Canonical;
2761  if (!ObjectT.isCanonical()) {
2762    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2763
2764    // Regenerate InsertPos.
2765    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2766  }
2767
2768  // No match.
2769  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2770  ObjCObjectPointerType *QType =
2771    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2772
2773  Types.push_back(QType);
2774  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2775  return QualType(QType, 0);
2776}
2777
2778/// getObjCInterfaceType - Return the unique reference to the type for the
2779/// specified ObjC interface decl. The list of protocols is optional.
2780QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl) const {
2781  if (Decl->TypeForDecl)
2782    return QualType(Decl->TypeForDecl, 0);
2783
2784  // FIXME: redeclarations?
2785  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2786  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2787  Decl->TypeForDecl = T;
2788  Types.push_back(T);
2789  return QualType(T, 0);
2790}
2791
2792/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2793/// TypeOfExprType AST's (since expression's are never shared). For example,
2794/// multiple declarations that refer to "typeof(x)" all contain different
2795/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2796/// on canonical type's (which are always unique).
2797QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
2798  TypeOfExprType *toe;
2799  if (tofExpr->isTypeDependent()) {
2800    llvm::FoldingSetNodeID ID;
2801    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2802
2803    void *InsertPos = 0;
2804    DependentTypeOfExprType *Canon
2805      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2806    if (Canon) {
2807      // We already have a "canonical" version of an identical, dependent
2808      // typeof(expr) type. Use that as our canonical type.
2809      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2810                                          QualType((TypeOfExprType*)Canon, 0));
2811    } else {
2812      // Build a new, canonical typeof(expr) type.
2813      Canon
2814        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2815      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2816      toe = Canon;
2817    }
2818  } else {
2819    QualType Canonical = getCanonicalType(tofExpr->getType());
2820    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2821  }
2822  Types.push_back(toe);
2823  return QualType(toe, 0);
2824}
2825
2826/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2827/// TypeOfType AST's. The only motivation to unique these nodes would be
2828/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2829/// an issue. This doesn't effect the type checker, since it operates
2830/// on canonical type's (which are always unique).
2831QualType ASTContext::getTypeOfType(QualType tofType) const {
2832  QualType Canonical = getCanonicalType(tofType);
2833  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2834  Types.push_back(tot);
2835  return QualType(tot, 0);
2836}
2837
2838/// getDecltypeForExpr - Given an expr, will return the decltype for that
2839/// expression, according to the rules in C++0x [dcl.type.simple]p4
2840static QualType getDecltypeForExpr(const Expr *e, const ASTContext &Context) {
2841  if (e->isTypeDependent())
2842    return Context.DependentTy;
2843
2844  // If e is an id expression or a class member access, decltype(e) is defined
2845  // as the type of the entity named by e.
2846  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2847    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2848      return VD->getType();
2849  }
2850  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2851    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2852      return FD->getType();
2853  }
2854  // If e is a function call or an invocation of an overloaded operator,
2855  // (parentheses around e are ignored), decltype(e) is defined as the
2856  // return type of that function.
2857  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2858    return CE->getCallReturnType();
2859
2860  QualType T = e->getType();
2861
2862  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2863  // defined as T&, otherwise decltype(e) is defined as T.
2864  if (e->isLValue())
2865    T = Context.getLValueReferenceType(T);
2866
2867  return T;
2868}
2869
2870/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2871/// DecltypeType AST's. The only motivation to unique these nodes would be
2872/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2873/// an issue. This doesn't effect the type checker, since it operates
2874/// on canonical type's (which are always unique).
2875QualType ASTContext::getDecltypeType(Expr *e) const {
2876  DecltypeType *dt;
2877
2878  // C++0x [temp.type]p2:
2879  //   If an expression e involves a template parameter, decltype(e) denotes a
2880  //   unique dependent type. Two such decltype-specifiers refer to the same
2881  //   type only if their expressions are equivalent (14.5.6.1).
2882  if (e->isInstantiationDependent()) {
2883    llvm::FoldingSetNodeID ID;
2884    DependentDecltypeType::Profile(ID, *this, e);
2885
2886    void *InsertPos = 0;
2887    DependentDecltypeType *Canon
2888      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2889    if (Canon) {
2890      // We already have a "canonical" version of an equivalent, dependent
2891      // decltype type. Use that as our canonical type.
2892      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2893                                       QualType((DecltypeType*)Canon, 0));
2894    } else {
2895      // Build a new, canonical typeof(expr) type.
2896      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2897      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2898      dt = Canon;
2899    }
2900  } else {
2901    QualType T = getDecltypeForExpr(e, *this);
2902    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2903  }
2904  Types.push_back(dt);
2905  return QualType(dt, 0);
2906}
2907
2908/// getUnaryTransformationType - We don't unique these, since the memory
2909/// savings are minimal and these are rare.
2910QualType ASTContext::getUnaryTransformType(QualType BaseType,
2911                                           QualType UnderlyingType,
2912                                           UnaryTransformType::UTTKind Kind)
2913    const {
2914  UnaryTransformType *Ty =
2915    new (*this, TypeAlignment) UnaryTransformType (BaseType, UnderlyingType,
2916                                                   Kind,
2917                                 UnderlyingType->isDependentType() ?
2918                                    QualType() : UnderlyingType);
2919  Types.push_back(Ty);
2920  return QualType(Ty, 0);
2921}
2922
2923/// getAutoType - We only unique auto types after they've been deduced.
2924QualType ASTContext::getAutoType(QualType DeducedType) const {
2925  void *InsertPos = 0;
2926  if (!DeducedType.isNull()) {
2927    // Look in the folding set for an existing type.
2928    llvm::FoldingSetNodeID ID;
2929    AutoType::Profile(ID, DeducedType);
2930    if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
2931      return QualType(AT, 0);
2932  }
2933
2934  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType);
2935  Types.push_back(AT);
2936  if (InsertPos)
2937    AutoTypes.InsertNode(AT, InsertPos);
2938  return QualType(AT, 0);
2939}
2940
2941/// getAtomicType - Return the uniqued reference to the atomic type for
2942/// the given value type.
2943QualType ASTContext::getAtomicType(QualType T) const {
2944  // Unique pointers, to guarantee there is only one pointer of a particular
2945  // structure.
2946  llvm::FoldingSetNodeID ID;
2947  AtomicType::Profile(ID, T);
2948
2949  void *InsertPos = 0;
2950  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
2951    return QualType(AT, 0);
2952
2953  // If the atomic value type isn't canonical, this won't be a canonical type
2954  // either, so fill in the canonical type field.
2955  QualType Canonical;
2956  if (!T.isCanonical()) {
2957    Canonical = getAtomicType(getCanonicalType(T));
2958
2959    // Get the new insert position for the node we care about.
2960    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
2961    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2962  }
2963  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
2964  Types.push_back(New);
2965  AtomicTypes.InsertNode(New, InsertPos);
2966  return QualType(New, 0);
2967}
2968
2969/// getAutoDeductType - Get type pattern for deducing against 'auto'.
2970QualType ASTContext::getAutoDeductType() const {
2971  if (AutoDeductTy.isNull())
2972    AutoDeductTy = getAutoType(QualType());
2973  assert(!AutoDeductTy.isNull() && "can't build 'auto' pattern");
2974  return AutoDeductTy;
2975}
2976
2977/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
2978QualType ASTContext::getAutoRRefDeductType() const {
2979  if (AutoRRefDeductTy.isNull())
2980    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
2981  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
2982  return AutoRRefDeductTy;
2983}
2984
2985/// getTagDeclType - Return the unique reference to the type for the
2986/// specified TagDecl (struct/union/class/enum) decl.
2987QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
2988  assert (Decl);
2989  // FIXME: What is the design on getTagDeclType when it requires casting
2990  // away const?  mutable?
2991  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2992}
2993
2994/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2995/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2996/// needs to agree with the definition in <stddef.h>.
2997CanQualType ASTContext::getSizeType() const {
2998  return getFromTargetType(Target->getSizeType());
2999}
3000
3001/// getSignedWCharType - Return the type of "signed wchar_t".
3002/// Used when in C++, as a GCC extension.
3003QualType ASTContext::getSignedWCharType() const {
3004  // FIXME: derive from "Target" ?
3005  return WCharTy;
3006}
3007
3008/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
3009/// Used when in C++, as a GCC extension.
3010QualType ASTContext::getUnsignedWCharType() const {
3011  // FIXME: derive from "Target" ?
3012  return UnsignedIntTy;
3013}
3014
3015/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
3016/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
3017QualType ASTContext::getPointerDiffType() const {
3018  return getFromTargetType(Target->getPtrDiffType(0));
3019}
3020
3021//===----------------------------------------------------------------------===//
3022//                              Type Operators
3023//===----------------------------------------------------------------------===//
3024
3025CanQualType ASTContext::getCanonicalParamType(QualType T) const {
3026  // Push qualifiers into arrays, and then discard any remaining
3027  // qualifiers.
3028  T = getCanonicalType(T);
3029  T = getVariableArrayDecayedType(T);
3030  const Type *Ty = T.getTypePtr();
3031  QualType Result;
3032  if (isa<ArrayType>(Ty)) {
3033    Result = getArrayDecayedType(QualType(Ty,0));
3034  } else if (isa<FunctionType>(Ty)) {
3035    Result = getPointerType(QualType(Ty, 0));
3036  } else {
3037    Result = QualType(Ty, 0);
3038  }
3039
3040  return CanQualType::CreateUnsafe(Result);
3041}
3042
3043QualType ASTContext::getUnqualifiedArrayType(QualType type,
3044                                             Qualifiers &quals) {
3045  SplitQualType splitType = type.getSplitUnqualifiedType();
3046
3047  // FIXME: getSplitUnqualifiedType() actually walks all the way to
3048  // the unqualified desugared type and then drops it on the floor.
3049  // We then have to strip that sugar back off with
3050  // getUnqualifiedDesugaredType(), which is silly.
3051  const ArrayType *AT =
3052    dyn_cast<ArrayType>(splitType.first->getUnqualifiedDesugaredType());
3053
3054  // If we don't have an array, just use the results in splitType.
3055  if (!AT) {
3056    quals = splitType.second;
3057    return QualType(splitType.first, 0);
3058  }
3059
3060  // Otherwise, recurse on the array's element type.
3061  QualType elementType = AT->getElementType();
3062  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
3063
3064  // If that didn't change the element type, AT has no qualifiers, so we
3065  // can just use the results in splitType.
3066  if (elementType == unqualElementType) {
3067    assert(quals.empty()); // from the recursive call
3068    quals = splitType.second;
3069    return QualType(splitType.first, 0);
3070  }
3071
3072  // Otherwise, add in the qualifiers from the outermost type, then
3073  // build the type back up.
3074  quals.addConsistentQualifiers(splitType.second);
3075
3076  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
3077    return getConstantArrayType(unqualElementType, CAT->getSize(),
3078                                CAT->getSizeModifier(), 0);
3079  }
3080
3081  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
3082    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
3083  }
3084
3085  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
3086    return getVariableArrayType(unqualElementType,
3087                                VAT->getSizeExpr(),
3088                                VAT->getSizeModifier(),
3089                                VAT->getIndexTypeCVRQualifiers(),
3090                                VAT->getBracketsRange());
3091  }
3092
3093  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
3094  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
3095                                    DSAT->getSizeModifier(), 0,
3096                                    SourceRange());
3097}
3098
3099/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
3100/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
3101/// they point to and return true. If T1 and T2 aren't pointer types
3102/// or pointer-to-member types, or if they are not similar at this
3103/// level, returns false and leaves T1 and T2 unchanged. Top-level
3104/// qualifiers on T1 and T2 are ignored. This function will typically
3105/// be called in a loop that successively "unwraps" pointer and
3106/// pointer-to-member types to compare them at each level.
3107bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
3108  const PointerType *T1PtrType = T1->getAs<PointerType>(),
3109                    *T2PtrType = T2->getAs<PointerType>();
3110  if (T1PtrType && T2PtrType) {
3111    T1 = T1PtrType->getPointeeType();
3112    T2 = T2PtrType->getPointeeType();
3113    return true;
3114  }
3115
3116  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
3117                          *T2MPType = T2->getAs<MemberPointerType>();
3118  if (T1MPType && T2MPType &&
3119      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
3120                             QualType(T2MPType->getClass(), 0))) {
3121    T1 = T1MPType->getPointeeType();
3122    T2 = T2MPType->getPointeeType();
3123    return true;
3124  }
3125
3126  if (getLangOptions().ObjC1) {
3127    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
3128                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
3129    if (T1OPType && T2OPType) {
3130      T1 = T1OPType->getPointeeType();
3131      T2 = T2OPType->getPointeeType();
3132      return true;
3133    }
3134  }
3135
3136  // FIXME: Block pointers, too?
3137
3138  return false;
3139}
3140
3141DeclarationNameInfo
3142ASTContext::getNameForTemplate(TemplateName Name,
3143                               SourceLocation NameLoc) const {
3144  switch (Name.getKind()) {
3145  case TemplateName::QualifiedTemplate:
3146  case TemplateName::Template:
3147    // DNInfo work in progress: CHECKME: what about DNLoc?
3148    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
3149                               NameLoc);
3150
3151  case TemplateName::OverloadedTemplate: {
3152    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
3153    // DNInfo work in progress: CHECKME: what about DNLoc?
3154    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
3155  }
3156
3157  case TemplateName::DependentTemplate: {
3158    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3159    DeclarationName DName;
3160    if (DTN->isIdentifier()) {
3161      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
3162      return DeclarationNameInfo(DName, NameLoc);
3163    } else {
3164      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
3165      // DNInfo work in progress: FIXME: source locations?
3166      DeclarationNameLoc DNLoc;
3167      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
3168      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
3169      return DeclarationNameInfo(DName, NameLoc, DNLoc);
3170    }
3171  }
3172
3173  case TemplateName::SubstTemplateTemplateParm: {
3174    SubstTemplateTemplateParmStorage *subst
3175      = Name.getAsSubstTemplateTemplateParm();
3176    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
3177                               NameLoc);
3178  }
3179
3180  case TemplateName::SubstTemplateTemplateParmPack: {
3181    SubstTemplateTemplateParmPackStorage *subst
3182      = Name.getAsSubstTemplateTemplateParmPack();
3183    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
3184                               NameLoc);
3185  }
3186  }
3187
3188  llvm_unreachable("bad template name kind!");
3189}
3190
3191TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
3192  switch (Name.getKind()) {
3193  case TemplateName::QualifiedTemplate:
3194  case TemplateName::Template: {
3195    TemplateDecl *Template = Name.getAsTemplateDecl();
3196    if (TemplateTemplateParmDecl *TTP
3197          = dyn_cast<TemplateTemplateParmDecl>(Template))
3198      Template = getCanonicalTemplateTemplateParmDecl(TTP);
3199
3200    // The canonical template name is the canonical template declaration.
3201    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
3202  }
3203
3204  case TemplateName::OverloadedTemplate:
3205    llvm_unreachable("cannot canonicalize overloaded template");
3206
3207  case TemplateName::DependentTemplate: {
3208    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3209    assert(DTN && "Non-dependent template names must refer to template decls.");
3210    return DTN->CanonicalTemplateName;
3211  }
3212
3213  case TemplateName::SubstTemplateTemplateParm: {
3214    SubstTemplateTemplateParmStorage *subst
3215      = Name.getAsSubstTemplateTemplateParm();
3216    return getCanonicalTemplateName(subst->getReplacement());
3217  }
3218
3219  case TemplateName::SubstTemplateTemplateParmPack: {
3220    SubstTemplateTemplateParmPackStorage *subst
3221                                  = Name.getAsSubstTemplateTemplateParmPack();
3222    TemplateTemplateParmDecl *canonParameter
3223      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
3224    TemplateArgument canonArgPack
3225      = getCanonicalTemplateArgument(subst->getArgumentPack());
3226    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
3227  }
3228  }
3229
3230  llvm_unreachable("bad template name!");
3231}
3232
3233bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
3234  X = getCanonicalTemplateName(X);
3235  Y = getCanonicalTemplateName(Y);
3236  return X.getAsVoidPointer() == Y.getAsVoidPointer();
3237}
3238
3239TemplateArgument
3240ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
3241  switch (Arg.getKind()) {
3242    case TemplateArgument::Null:
3243      return Arg;
3244
3245    case TemplateArgument::Expression:
3246      return Arg;
3247
3248    case TemplateArgument::Declaration:
3249      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
3250
3251    case TemplateArgument::Template:
3252      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
3253
3254    case TemplateArgument::TemplateExpansion:
3255      return TemplateArgument(getCanonicalTemplateName(
3256                                         Arg.getAsTemplateOrTemplatePattern()),
3257                              Arg.getNumTemplateExpansions());
3258
3259    case TemplateArgument::Integral:
3260      return TemplateArgument(*Arg.getAsIntegral(),
3261                              getCanonicalType(Arg.getIntegralType()));
3262
3263    case TemplateArgument::Type:
3264      return TemplateArgument(getCanonicalType(Arg.getAsType()));
3265
3266    case TemplateArgument::Pack: {
3267      if (Arg.pack_size() == 0)
3268        return Arg;
3269
3270      TemplateArgument *CanonArgs
3271        = new (*this) TemplateArgument[Arg.pack_size()];
3272      unsigned Idx = 0;
3273      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
3274                                        AEnd = Arg.pack_end();
3275           A != AEnd; (void)++A, ++Idx)
3276        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
3277
3278      return TemplateArgument(CanonArgs, Arg.pack_size());
3279    }
3280  }
3281
3282  // Silence GCC warning
3283  llvm_unreachable("Unhandled template argument kind");
3284}
3285
3286NestedNameSpecifier *
3287ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
3288  if (!NNS)
3289    return 0;
3290
3291  switch (NNS->getKind()) {
3292  case NestedNameSpecifier::Identifier:
3293    // Canonicalize the prefix but keep the identifier the same.
3294    return NestedNameSpecifier::Create(*this,
3295                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
3296                                       NNS->getAsIdentifier());
3297
3298  case NestedNameSpecifier::Namespace:
3299    // A namespace is canonical; build a nested-name-specifier with
3300    // this namespace and no prefix.
3301    return NestedNameSpecifier::Create(*this, 0,
3302                                 NNS->getAsNamespace()->getOriginalNamespace());
3303
3304  case NestedNameSpecifier::NamespaceAlias:
3305    // A namespace is canonical; build a nested-name-specifier with
3306    // this namespace and no prefix.
3307    return NestedNameSpecifier::Create(*this, 0,
3308                                    NNS->getAsNamespaceAlias()->getNamespace()
3309                                                      ->getOriginalNamespace());
3310
3311  case NestedNameSpecifier::TypeSpec:
3312  case NestedNameSpecifier::TypeSpecWithTemplate: {
3313    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
3314
3315    // If we have some kind of dependent-named type (e.g., "typename T::type"),
3316    // break it apart into its prefix and identifier, then reconsititute those
3317    // as the canonical nested-name-specifier. This is required to canonicalize
3318    // a dependent nested-name-specifier involving typedefs of dependent-name
3319    // types, e.g.,
3320    //   typedef typename T::type T1;
3321    //   typedef typename T1::type T2;
3322    if (const DependentNameType *DNT = T->getAs<DependentNameType>()) {
3323      NestedNameSpecifier *Prefix
3324        = getCanonicalNestedNameSpecifier(DNT->getQualifier());
3325      return NestedNameSpecifier::Create(*this, Prefix,
3326                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
3327    }
3328
3329    // Do the same thing as above, but with dependent-named specializations.
3330    if (const DependentTemplateSpecializationType *DTST
3331          = T->getAs<DependentTemplateSpecializationType>()) {
3332      NestedNameSpecifier *Prefix
3333        = getCanonicalNestedNameSpecifier(DTST->getQualifier());
3334
3335      T = getDependentTemplateSpecializationType(DTST->getKeyword(),
3336                                                 Prefix, DTST->getIdentifier(),
3337                                                 DTST->getNumArgs(),
3338                                                 DTST->getArgs());
3339      T = getCanonicalType(T);
3340    }
3341
3342    return NestedNameSpecifier::Create(*this, 0, false,
3343                                       const_cast<Type*>(T.getTypePtr()));
3344  }
3345
3346  case NestedNameSpecifier::Global:
3347    // The global specifier is canonical and unique.
3348    return NNS;
3349  }
3350
3351  // Required to silence a GCC warning
3352  return 0;
3353}
3354
3355
3356const ArrayType *ASTContext::getAsArrayType(QualType T) const {
3357  // Handle the non-qualified case efficiently.
3358  if (!T.hasLocalQualifiers()) {
3359    // Handle the common positive case fast.
3360    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
3361      return AT;
3362  }
3363
3364  // Handle the common negative case fast.
3365  if (!isa<ArrayType>(T.getCanonicalType()))
3366    return 0;
3367
3368  // Apply any qualifiers from the array type to the element type.  This
3369  // implements C99 6.7.3p8: "If the specification of an array type includes
3370  // any type qualifiers, the element type is so qualified, not the array type."
3371
3372  // If we get here, we either have type qualifiers on the type, or we have
3373  // sugar such as a typedef in the way.  If we have type qualifiers on the type
3374  // we must propagate them down into the element type.
3375
3376  SplitQualType split = T.getSplitDesugaredType();
3377  Qualifiers qs = split.second;
3378
3379  // If we have a simple case, just return now.
3380  const ArrayType *ATy = dyn_cast<ArrayType>(split.first);
3381  if (ATy == 0 || qs.empty())
3382    return ATy;
3383
3384  // Otherwise, we have an array and we have qualifiers on it.  Push the
3385  // qualifiers into the array element type and return a new array type.
3386  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
3387
3388  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
3389    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
3390                                                CAT->getSizeModifier(),
3391                                           CAT->getIndexTypeCVRQualifiers()));
3392  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
3393    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
3394                                                  IAT->getSizeModifier(),
3395                                           IAT->getIndexTypeCVRQualifiers()));
3396
3397  if (const DependentSizedArrayType *DSAT
3398        = dyn_cast<DependentSizedArrayType>(ATy))
3399    return cast<ArrayType>(
3400                     getDependentSizedArrayType(NewEltTy,
3401                                                DSAT->getSizeExpr(),
3402                                                DSAT->getSizeModifier(),
3403                                              DSAT->getIndexTypeCVRQualifiers(),
3404                                                DSAT->getBracketsRange()));
3405
3406  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
3407  return cast<ArrayType>(getVariableArrayType(NewEltTy,
3408                                              VAT->getSizeExpr(),
3409                                              VAT->getSizeModifier(),
3410                                              VAT->getIndexTypeCVRQualifiers(),
3411                                              VAT->getBracketsRange()));
3412}
3413
3414QualType ASTContext::getAdjustedParameterType(QualType T) {
3415  // C99 6.7.5.3p7:
3416  //   A declaration of a parameter as "array of type" shall be
3417  //   adjusted to "qualified pointer to type", where the type
3418  //   qualifiers (if any) are those specified within the [ and ] of
3419  //   the array type derivation.
3420  if (T->isArrayType())
3421    return getArrayDecayedType(T);
3422
3423  // C99 6.7.5.3p8:
3424  //   A declaration of a parameter as "function returning type"
3425  //   shall be adjusted to "pointer to function returning type", as
3426  //   in 6.3.2.1.
3427  if (T->isFunctionType())
3428    return getPointerType(T);
3429
3430  return T;
3431}
3432
3433QualType ASTContext::getSignatureParameterType(QualType T) {
3434  T = getVariableArrayDecayedType(T);
3435  T = getAdjustedParameterType(T);
3436  return T.getUnqualifiedType();
3437}
3438
3439/// getArrayDecayedType - Return the properly qualified result of decaying the
3440/// specified array type to a pointer.  This operation is non-trivial when
3441/// handling typedefs etc.  The canonical type of "T" must be an array type,
3442/// this returns a pointer to a properly qualified element of the array.
3443///
3444/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
3445QualType ASTContext::getArrayDecayedType(QualType Ty) const {
3446  // Get the element type with 'getAsArrayType' so that we don't lose any
3447  // typedefs in the element type of the array.  This also handles propagation
3448  // of type qualifiers from the array type into the element type if present
3449  // (C99 6.7.3p8).
3450  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
3451  assert(PrettyArrayType && "Not an array type!");
3452
3453  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
3454
3455  // int x[restrict 4] ->  int *restrict
3456  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
3457}
3458
3459QualType ASTContext::getBaseElementType(const ArrayType *array) const {
3460  return getBaseElementType(array->getElementType());
3461}
3462
3463QualType ASTContext::getBaseElementType(QualType type) const {
3464  Qualifiers qs;
3465  while (true) {
3466    SplitQualType split = type.getSplitDesugaredType();
3467    const ArrayType *array = split.first->getAsArrayTypeUnsafe();
3468    if (!array) break;
3469
3470    type = array->getElementType();
3471    qs.addConsistentQualifiers(split.second);
3472  }
3473
3474  return getQualifiedType(type, qs);
3475}
3476
3477/// getConstantArrayElementCount - Returns number of constant array elements.
3478uint64_t
3479ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
3480  uint64_t ElementCount = 1;
3481  do {
3482    ElementCount *= CA->getSize().getZExtValue();
3483    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
3484  } while (CA);
3485  return ElementCount;
3486}
3487
3488/// getFloatingRank - Return a relative rank for floating point types.
3489/// This routine will assert if passed a built-in type that isn't a float.
3490static FloatingRank getFloatingRank(QualType T) {
3491  if (const ComplexType *CT = T->getAs<ComplexType>())
3492    return getFloatingRank(CT->getElementType());
3493
3494  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
3495  switch (T->getAs<BuiltinType>()->getKind()) {
3496  default: llvm_unreachable("getFloatingRank(): not a floating type");
3497  case BuiltinType::Half:       return HalfRank;
3498  case BuiltinType::Float:      return FloatRank;
3499  case BuiltinType::Double:     return DoubleRank;
3500  case BuiltinType::LongDouble: return LongDoubleRank;
3501  }
3502}
3503
3504/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
3505/// point or a complex type (based on typeDomain/typeSize).
3506/// 'typeDomain' is a real floating point or complex type.
3507/// 'typeSize' is a real floating point or complex type.
3508QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
3509                                                       QualType Domain) const {
3510  FloatingRank EltRank = getFloatingRank(Size);
3511  if (Domain->isComplexType()) {
3512    switch (EltRank) {
3513    default: llvm_unreachable("getFloatingRank(): illegal value for rank");
3514    case FloatRank:      return FloatComplexTy;
3515    case DoubleRank:     return DoubleComplexTy;
3516    case LongDoubleRank: return LongDoubleComplexTy;
3517    }
3518  }
3519
3520  assert(Domain->isRealFloatingType() && "Unknown domain!");
3521  switch (EltRank) {
3522  default: llvm_unreachable("getFloatingRank(): illegal value for rank");
3523  case FloatRank:      return FloatTy;
3524  case DoubleRank:     return DoubleTy;
3525  case LongDoubleRank: return LongDoubleTy;
3526  }
3527}
3528
3529/// getFloatingTypeOrder - Compare the rank of the two specified floating
3530/// point types, ignoring the domain of the type (i.e. 'double' ==
3531/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3532/// LHS < RHS, return -1.
3533int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
3534  FloatingRank LHSR = getFloatingRank(LHS);
3535  FloatingRank RHSR = getFloatingRank(RHS);
3536
3537  if (LHSR == RHSR)
3538    return 0;
3539  if (LHSR > RHSR)
3540    return 1;
3541  return -1;
3542}
3543
3544/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
3545/// routine will assert if passed a built-in type that isn't an integer or enum,
3546/// or if it is not canonicalized.
3547unsigned ASTContext::getIntegerRank(const Type *T) const {
3548  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
3549  if (const EnumType* ET = dyn_cast<EnumType>(T))
3550    T = ET->getDecl()->getPromotionType().getTypePtr();
3551
3552  if (T->isSpecificBuiltinType(BuiltinType::WChar_S) ||
3553      T->isSpecificBuiltinType(BuiltinType::WChar_U))
3554    T = getFromTargetType(Target->getWCharType()).getTypePtr();
3555
3556  if (T->isSpecificBuiltinType(BuiltinType::Char16))
3557    T = getFromTargetType(Target->getChar16Type()).getTypePtr();
3558
3559  if (T->isSpecificBuiltinType(BuiltinType::Char32))
3560    T = getFromTargetType(Target->getChar32Type()).getTypePtr();
3561
3562  switch (cast<BuiltinType>(T)->getKind()) {
3563  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
3564  case BuiltinType::Bool:
3565    return 1 + (getIntWidth(BoolTy) << 3);
3566  case BuiltinType::Char_S:
3567  case BuiltinType::Char_U:
3568  case BuiltinType::SChar:
3569  case BuiltinType::UChar:
3570    return 2 + (getIntWidth(CharTy) << 3);
3571  case BuiltinType::Short:
3572  case BuiltinType::UShort:
3573    return 3 + (getIntWidth(ShortTy) << 3);
3574  case BuiltinType::Int:
3575  case BuiltinType::UInt:
3576    return 4 + (getIntWidth(IntTy) << 3);
3577  case BuiltinType::Long:
3578  case BuiltinType::ULong:
3579    return 5 + (getIntWidth(LongTy) << 3);
3580  case BuiltinType::LongLong:
3581  case BuiltinType::ULongLong:
3582    return 6 + (getIntWidth(LongLongTy) << 3);
3583  case BuiltinType::Int128:
3584  case BuiltinType::UInt128:
3585    return 7 + (getIntWidth(Int128Ty) << 3);
3586  }
3587}
3588
3589/// \brief Whether this is a promotable bitfield reference according
3590/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
3591///
3592/// \returns the type this bit-field will promote to, or NULL if no
3593/// promotion occurs.
3594QualType ASTContext::isPromotableBitField(Expr *E) const {
3595  if (E->isTypeDependent() || E->isValueDependent())
3596    return QualType();
3597
3598  FieldDecl *Field = E->getBitField();
3599  if (!Field)
3600    return QualType();
3601
3602  QualType FT = Field->getType();
3603
3604  uint64_t BitWidth = Field->getBitWidthValue(*this);
3605  uint64_t IntSize = getTypeSize(IntTy);
3606  // GCC extension compatibility: if the bit-field size is less than or equal
3607  // to the size of int, it gets promoted no matter what its type is.
3608  // For instance, unsigned long bf : 4 gets promoted to signed int.
3609  if (BitWidth < IntSize)
3610    return IntTy;
3611
3612  if (BitWidth == IntSize)
3613    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
3614
3615  // Types bigger than int are not subject to promotions, and therefore act
3616  // like the base type.
3617  // FIXME: This doesn't quite match what gcc does, but what gcc does here
3618  // is ridiculous.
3619  return QualType();
3620}
3621
3622/// getPromotedIntegerType - Returns the type that Promotable will
3623/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
3624/// integer type.
3625QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
3626  assert(!Promotable.isNull());
3627  assert(Promotable->isPromotableIntegerType());
3628  if (const EnumType *ET = Promotable->getAs<EnumType>())
3629    return ET->getDecl()->getPromotionType();
3630  if (Promotable->isSignedIntegerType())
3631    return IntTy;
3632  uint64_t PromotableSize = getTypeSize(Promotable);
3633  uint64_t IntSize = getTypeSize(IntTy);
3634  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3635  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3636}
3637
3638/// \brief Recurses in pointer/array types until it finds an objc retainable
3639/// type and returns its ownership.
3640Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
3641  while (!T.isNull()) {
3642    if (T.getObjCLifetime() != Qualifiers::OCL_None)
3643      return T.getObjCLifetime();
3644    if (T->isArrayType())
3645      T = getBaseElementType(T);
3646    else if (const PointerType *PT = T->getAs<PointerType>())
3647      T = PT->getPointeeType();
3648    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3649      T = RT->getPointeeType();
3650    else
3651      break;
3652  }
3653
3654  return Qualifiers::OCL_None;
3655}
3656
3657/// getIntegerTypeOrder - Returns the highest ranked integer type:
3658/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3659/// LHS < RHS, return -1.
3660int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
3661  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
3662  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
3663  if (LHSC == RHSC) return 0;
3664
3665  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3666  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3667
3668  unsigned LHSRank = getIntegerRank(LHSC);
3669  unsigned RHSRank = getIntegerRank(RHSC);
3670
3671  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3672    if (LHSRank == RHSRank) return 0;
3673    return LHSRank > RHSRank ? 1 : -1;
3674  }
3675
3676  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3677  if (LHSUnsigned) {
3678    // If the unsigned [LHS] type is larger, return it.
3679    if (LHSRank >= RHSRank)
3680      return 1;
3681
3682    // If the signed type can represent all values of the unsigned type, it
3683    // wins.  Because we are dealing with 2's complement and types that are
3684    // powers of two larger than each other, this is always safe.
3685    return -1;
3686  }
3687
3688  // If the unsigned [RHS] type is larger, return it.
3689  if (RHSRank >= LHSRank)
3690    return -1;
3691
3692  // If the signed type can represent all values of the unsigned type, it
3693  // wins.  Because we are dealing with 2's complement and types that are
3694  // powers of two larger than each other, this is always safe.
3695  return 1;
3696}
3697
3698static RecordDecl *
3699CreateRecordDecl(const ASTContext &Ctx, RecordDecl::TagKind TK,
3700                 DeclContext *DC, IdentifierInfo *Id) {
3701  SourceLocation Loc;
3702  if (Ctx.getLangOptions().CPlusPlus)
3703    return CXXRecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3704  else
3705    return RecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
3706}
3707
3708// getCFConstantStringType - Return the type used for constant CFStrings.
3709QualType ASTContext::getCFConstantStringType() const {
3710  if (!CFConstantStringTypeDecl) {
3711    CFConstantStringTypeDecl =
3712      CreateRecordDecl(*this, TTK_Struct, TUDecl,
3713                       &Idents.get("NSConstantString"));
3714    CFConstantStringTypeDecl->startDefinition();
3715
3716    QualType FieldTypes[4];
3717
3718    // const int *isa;
3719    FieldTypes[0] = getPointerType(IntTy.withConst());
3720    // int flags;
3721    FieldTypes[1] = IntTy;
3722    // const char *str;
3723    FieldTypes[2] = getPointerType(CharTy.withConst());
3724    // long length;
3725    FieldTypes[3] = LongTy;
3726
3727    // Create fields
3728    for (unsigned i = 0; i < 4; ++i) {
3729      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3730                                           SourceLocation(),
3731                                           SourceLocation(), 0,
3732                                           FieldTypes[i], /*TInfo=*/0,
3733                                           /*BitWidth=*/0,
3734                                           /*Mutable=*/false,
3735                                           /*HasInit=*/false);
3736      Field->setAccess(AS_public);
3737      CFConstantStringTypeDecl->addDecl(Field);
3738    }
3739
3740    CFConstantStringTypeDecl->completeDefinition();
3741  }
3742
3743  return getTagDeclType(CFConstantStringTypeDecl);
3744}
3745
3746void ASTContext::setCFConstantStringType(QualType T) {
3747  const RecordType *Rec = T->getAs<RecordType>();
3748  assert(Rec && "Invalid CFConstantStringType");
3749  CFConstantStringTypeDecl = Rec->getDecl();
3750}
3751
3752QualType ASTContext::getBlockDescriptorType() const {
3753  if (BlockDescriptorType)
3754    return getTagDeclType(BlockDescriptorType);
3755
3756  RecordDecl *T;
3757  // FIXME: Needs the FlagAppleBlock bit.
3758  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3759                       &Idents.get("__block_descriptor"));
3760  T->startDefinition();
3761
3762  QualType FieldTypes[] = {
3763    UnsignedLongTy,
3764    UnsignedLongTy,
3765  };
3766
3767  const char *FieldNames[] = {
3768    "reserved",
3769    "Size"
3770  };
3771
3772  for (size_t i = 0; i < 2; ++i) {
3773    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3774                                         SourceLocation(),
3775                                         &Idents.get(FieldNames[i]),
3776                                         FieldTypes[i], /*TInfo=*/0,
3777                                         /*BitWidth=*/0,
3778                                         /*Mutable=*/false,
3779                                         /*HasInit=*/false);
3780    Field->setAccess(AS_public);
3781    T->addDecl(Field);
3782  }
3783
3784  T->completeDefinition();
3785
3786  BlockDescriptorType = T;
3787
3788  return getTagDeclType(BlockDescriptorType);
3789}
3790
3791QualType ASTContext::getBlockDescriptorExtendedType() const {
3792  if (BlockDescriptorExtendedType)
3793    return getTagDeclType(BlockDescriptorExtendedType);
3794
3795  RecordDecl *T;
3796  // FIXME: Needs the FlagAppleBlock bit.
3797  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
3798                       &Idents.get("__block_descriptor_withcopydispose"));
3799  T->startDefinition();
3800
3801  QualType FieldTypes[] = {
3802    UnsignedLongTy,
3803    UnsignedLongTy,
3804    getPointerType(VoidPtrTy),
3805    getPointerType(VoidPtrTy)
3806  };
3807
3808  const char *FieldNames[] = {
3809    "reserved",
3810    "Size",
3811    "CopyFuncPtr",
3812    "DestroyFuncPtr"
3813  };
3814
3815  for (size_t i = 0; i < 4; ++i) {
3816    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3817                                         SourceLocation(),
3818                                         &Idents.get(FieldNames[i]),
3819                                         FieldTypes[i], /*TInfo=*/0,
3820                                         /*BitWidth=*/0,
3821                                         /*Mutable=*/false,
3822                                         /*HasInit=*/false);
3823    Field->setAccess(AS_public);
3824    T->addDecl(Field);
3825  }
3826
3827  T->completeDefinition();
3828
3829  BlockDescriptorExtendedType = T;
3830
3831  return getTagDeclType(BlockDescriptorExtendedType);
3832}
3833
3834bool ASTContext::BlockRequiresCopying(QualType Ty) const {
3835  if (Ty->isObjCRetainableType())
3836    return true;
3837  if (getLangOptions().CPlusPlus) {
3838    if (const RecordType *RT = Ty->getAs<RecordType>()) {
3839      CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
3840      return RD->hasConstCopyConstructor();
3841
3842    }
3843  }
3844  return false;
3845}
3846
3847QualType
3848ASTContext::BuildByRefType(StringRef DeclName, QualType Ty) const {
3849  //  type = struct __Block_byref_1_X {
3850  //    void *__isa;
3851  //    struct __Block_byref_1_X *__forwarding;
3852  //    unsigned int __flags;
3853  //    unsigned int __size;
3854  //    void *__copy_helper;            // as needed
3855  //    void *__destroy_help            // as needed
3856  //    int X;
3857  //  } *
3858
3859  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3860
3861  // FIXME: Move up
3862  llvm::SmallString<36> Name;
3863  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3864                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3865  RecordDecl *T;
3866  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, &Idents.get(Name.str()));
3867  T->startDefinition();
3868  QualType Int32Ty = IntTy;
3869  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3870  QualType FieldTypes[] = {
3871    getPointerType(VoidPtrTy),
3872    getPointerType(getTagDeclType(T)),
3873    Int32Ty,
3874    Int32Ty,
3875    getPointerType(VoidPtrTy),
3876    getPointerType(VoidPtrTy),
3877    Ty
3878  };
3879
3880  StringRef FieldNames[] = {
3881    "__isa",
3882    "__forwarding",
3883    "__flags",
3884    "__size",
3885    "__copy_helper",
3886    "__destroy_helper",
3887    DeclName,
3888  };
3889
3890  for (size_t i = 0; i < 7; ++i) {
3891    if (!HasCopyAndDispose && i >=4 && i <= 5)
3892      continue;
3893    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3894                                         SourceLocation(),
3895                                         &Idents.get(FieldNames[i]),
3896                                         FieldTypes[i], /*TInfo=*/0,
3897                                         /*BitWidth=*/0, /*Mutable=*/false,
3898                                         /*HasInit=*/false);
3899    Field->setAccess(AS_public);
3900    T->addDecl(Field);
3901  }
3902
3903  T->completeDefinition();
3904
3905  return getPointerType(getTagDeclType(T));
3906}
3907
3908TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
3909  if (!ObjCInstanceTypeDecl)
3910    ObjCInstanceTypeDecl = TypedefDecl::Create(*this,
3911                                               getTranslationUnitDecl(),
3912                                               SourceLocation(),
3913                                               SourceLocation(),
3914                                               &Idents.get("instancetype"),
3915                                     getTrivialTypeSourceInfo(getObjCIdType()));
3916  return ObjCInstanceTypeDecl;
3917}
3918
3919// This returns true if a type has been typedefed to BOOL:
3920// typedef <type> BOOL;
3921static bool isTypeTypedefedAsBOOL(QualType T) {
3922  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3923    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3924      return II->isStr("BOOL");
3925
3926  return false;
3927}
3928
3929/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3930/// purpose.
3931CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
3932  if (!type->isIncompleteArrayType() && type->isIncompleteType())
3933    return CharUnits::Zero();
3934
3935  CharUnits sz = getTypeSizeInChars(type);
3936
3937  // Make all integer and enum types at least as large as an int
3938  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3939    sz = std::max(sz, getTypeSizeInChars(IntTy));
3940  // Treat arrays as pointers, since that's how they're passed in.
3941  else if (type->isArrayType())
3942    sz = getTypeSizeInChars(VoidPtrTy);
3943  return sz;
3944}
3945
3946static inline
3947std::string charUnitsToString(const CharUnits &CU) {
3948  return llvm::itostr(CU.getQuantity());
3949}
3950
3951/// getObjCEncodingForBlock - Return the encoded type for this block
3952/// declaration.
3953std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
3954  std::string S;
3955
3956  const BlockDecl *Decl = Expr->getBlockDecl();
3957  QualType BlockTy =
3958      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3959  // Encode result type.
3960  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3961  // Compute size of all parameters.
3962  // Start with computing size of a pointer in number of bytes.
3963  // FIXME: There might(should) be a better way of doing this computation!
3964  SourceLocation Loc;
3965  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3966  CharUnits ParmOffset = PtrSize;
3967  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3968       E = Decl->param_end(); PI != E; ++PI) {
3969    QualType PType = (*PI)->getType();
3970    CharUnits sz = getObjCEncodingTypeSize(PType);
3971    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3972    ParmOffset += sz;
3973  }
3974  // Size of the argument frame
3975  S += charUnitsToString(ParmOffset);
3976  // Block pointer and offset.
3977  S += "@?0";
3978
3979  // Argument types.
3980  ParmOffset = PtrSize;
3981  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3982       Decl->param_end(); PI != E; ++PI) {
3983    ParmVarDecl *PVDecl = *PI;
3984    QualType PType = PVDecl->getOriginalType();
3985    if (const ArrayType *AT =
3986          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3987      // Use array's original type only if it has known number of
3988      // elements.
3989      if (!isa<ConstantArrayType>(AT))
3990        PType = PVDecl->getType();
3991    } else if (PType->isFunctionType())
3992      PType = PVDecl->getType();
3993    getObjCEncodingForType(PType, S);
3994    S += charUnitsToString(ParmOffset);
3995    ParmOffset += getObjCEncodingTypeSize(PType);
3996  }
3997
3998  return S;
3999}
4000
4001bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
4002                                                std::string& S) {
4003  // Encode result type.
4004  getObjCEncodingForType(Decl->getResultType(), S);
4005  CharUnits ParmOffset;
4006  // Compute size of all parameters.
4007  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4008       E = Decl->param_end(); PI != E; ++PI) {
4009    QualType PType = (*PI)->getType();
4010    CharUnits sz = getObjCEncodingTypeSize(PType);
4011    if (sz.isZero())
4012      return true;
4013
4014    assert (sz.isPositive() &&
4015        "getObjCEncodingForFunctionDecl - Incomplete param type");
4016    ParmOffset += sz;
4017  }
4018  S += charUnitsToString(ParmOffset);
4019  ParmOffset = CharUnits::Zero();
4020
4021  // Argument types.
4022  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4023       E = Decl->param_end(); PI != E; ++PI) {
4024    ParmVarDecl *PVDecl = *PI;
4025    QualType PType = PVDecl->getOriginalType();
4026    if (const ArrayType *AT =
4027          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4028      // Use array's original type only if it has known number of
4029      // elements.
4030      if (!isa<ConstantArrayType>(AT))
4031        PType = PVDecl->getType();
4032    } else if (PType->isFunctionType())
4033      PType = PVDecl->getType();
4034    getObjCEncodingForType(PType, S);
4035    S += charUnitsToString(ParmOffset);
4036    ParmOffset += getObjCEncodingTypeSize(PType);
4037  }
4038
4039  return false;
4040}
4041
4042/// getObjCEncodingForMethodDecl - Return the encoded type for this method
4043/// declaration.
4044bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
4045                                              std::string& S) const {
4046  // FIXME: This is not very efficient.
4047  // Encode type qualifer, 'in', 'inout', etc. for the return type.
4048  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
4049  // Encode result type.
4050  getObjCEncodingForType(Decl->getResultType(), S);
4051  // Compute size of all parameters.
4052  // Start with computing size of a pointer in number of bytes.
4053  // FIXME: There might(should) be a better way of doing this computation!
4054  SourceLocation Loc;
4055  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4056  // The first two arguments (self and _cmd) are pointers; account for
4057  // their size.
4058  CharUnits ParmOffset = 2 * PtrSize;
4059  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4060       E = Decl->sel_param_end(); PI != E; ++PI) {
4061    QualType PType = (*PI)->getType();
4062    CharUnits sz = getObjCEncodingTypeSize(PType);
4063    if (sz.isZero())
4064      return true;
4065
4066    assert (sz.isPositive() &&
4067        "getObjCEncodingForMethodDecl - Incomplete param type");
4068    ParmOffset += sz;
4069  }
4070  S += charUnitsToString(ParmOffset);
4071  S += "@0:";
4072  S += charUnitsToString(PtrSize);
4073
4074  // Argument types.
4075  ParmOffset = 2 * PtrSize;
4076  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4077       E = Decl->sel_param_end(); PI != E; ++PI) {
4078    const ParmVarDecl *PVDecl = *PI;
4079    QualType PType = PVDecl->getOriginalType();
4080    if (const ArrayType *AT =
4081          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4082      // Use array's original type only if it has known number of
4083      // elements.
4084      if (!isa<ConstantArrayType>(AT))
4085        PType = PVDecl->getType();
4086    } else if (PType->isFunctionType())
4087      PType = PVDecl->getType();
4088    // Process argument qualifiers for user supplied arguments; such as,
4089    // 'in', 'inout', etc.
4090    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
4091    getObjCEncodingForType(PType, S);
4092    S += charUnitsToString(ParmOffset);
4093    ParmOffset += getObjCEncodingTypeSize(PType);
4094  }
4095
4096  return false;
4097}
4098
4099/// getObjCEncodingForPropertyDecl - Return the encoded type for this
4100/// property declaration. If non-NULL, Container must be either an
4101/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
4102/// NULL when getting encodings for protocol properties.
4103/// Property attributes are stored as a comma-delimited C string. The simple
4104/// attributes readonly and bycopy are encoded as single characters. The
4105/// parametrized attributes, getter=name, setter=name, and ivar=name, are
4106/// encoded as single characters, followed by an identifier. Property types
4107/// are also encoded as a parametrized attribute. The characters used to encode
4108/// these attributes are defined by the following enumeration:
4109/// @code
4110/// enum PropertyAttributes {
4111/// kPropertyReadOnly = 'R',   // property is read-only.
4112/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
4113/// kPropertyByref = '&',  // property is a reference to the value last assigned
4114/// kPropertyDynamic = 'D',    // property is dynamic
4115/// kPropertyGetter = 'G',     // followed by getter selector name
4116/// kPropertySetter = 'S',     // followed by setter selector name
4117/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
4118/// kPropertyType = 't'              // followed by old-style type encoding.
4119/// kPropertyWeak = 'W'              // 'weak' property
4120/// kPropertyStrong = 'P'            // property GC'able
4121/// kPropertyNonAtomic = 'N'         // property non-atomic
4122/// };
4123/// @endcode
4124void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
4125                                                const Decl *Container,
4126                                                std::string& S) const {
4127  // Collect information from the property implementation decl(s).
4128  bool Dynamic = false;
4129  ObjCPropertyImplDecl *SynthesizePID = 0;
4130
4131  // FIXME: Duplicated code due to poor abstraction.
4132  if (Container) {
4133    if (const ObjCCategoryImplDecl *CID =
4134        dyn_cast<ObjCCategoryImplDecl>(Container)) {
4135      for (ObjCCategoryImplDecl::propimpl_iterator
4136             i = CID->propimpl_begin(), e = CID->propimpl_end();
4137           i != e; ++i) {
4138        ObjCPropertyImplDecl *PID = *i;
4139        if (PID->getPropertyDecl() == PD) {
4140          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4141            Dynamic = true;
4142          } else {
4143            SynthesizePID = PID;
4144          }
4145        }
4146      }
4147    } else {
4148      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
4149      for (ObjCCategoryImplDecl::propimpl_iterator
4150             i = OID->propimpl_begin(), e = OID->propimpl_end();
4151           i != e; ++i) {
4152        ObjCPropertyImplDecl *PID = *i;
4153        if (PID->getPropertyDecl() == PD) {
4154          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4155            Dynamic = true;
4156          } else {
4157            SynthesizePID = PID;
4158          }
4159        }
4160      }
4161    }
4162  }
4163
4164  // FIXME: This is not very efficient.
4165  S = "T";
4166
4167  // Encode result type.
4168  // GCC has some special rules regarding encoding of properties which
4169  // closely resembles encoding of ivars.
4170  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
4171                             true /* outermost type */,
4172                             true /* encoding for property */);
4173
4174  if (PD->isReadOnly()) {
4175    S += ",R";
4176  } else {
4177    switch (PD->getSetterKind()) {
4178    case ObjCPropertyDecl::Assign: break;
4179    case ObjCPropertyDecl::Copy:   S += ",C"; break;
4180    case ObjCPropertyDecl::Retain: S += ",&"; break;
4181    case ObjCPropertyDecl::Weak:   S += ",W"; break;
4182    }
4183  }
4184
4185  // It really isn't clear at all what this means, since properties
4186  // are "dynamic by default".
4187  if (Dynamic)
4188    S += ",D";
4189
4190  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
4191    S += ",N";
4192
4193  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
4194    S += ",G";
4195    S += PD->getGetterName().getAsString();
4196  }
4197
4198  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
4199    S += ",S";
4200    S += PD->getSetterName().getAsString();
4201  }
4202
4203  if (SynthesizePID) {
4204    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
4205    S += ",V";
4206    S += OID->getNameAsString();
4207  }
4208
4209  // FIXME: OBJCGC: weak & strong
4210}
4211
4212/// getLegacyIntegralTypeEncoding -
4213/// Another legacy compatibility encoding: 32-bit longs are encoded as
4214/// 'l' or 'L' , but not always.  For typedefs, we need to use
4215/// 'i' or 'I' instead if encoding a struct field, or a pointer!
4216///
4217void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
4218  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
4219    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
4220      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
4221        PointeeTy = UnsignedIntTy;
4222      else
4223        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
4224          PointeeTy = IntTy;
4225    }
4226  }
4227}
4228
4229void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
4230                                        const FieldDecl *Field) const {
4231  // We follow the behavior of gcc, expanding structures which are
4232  // directly pointed to, and expanding embedded structures. Note that
4233  // these rules are sufficient to prevent recursive encoding of the
4234  // same type.
4235  getObjCEncodingForTypeImpl(T, S, true, true, Field,
4236                             true /* outermost type */);
4237}
4238
4239static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
4240    switch (T->getAs<BuiltinType>()->getKind()) {
4241    default: llvm_unreachable("Unhandled builtin type kind");
4242    case BuiltinType::Void:       return 'v';
4243    case BuiltinType::Bool:       return 'B';
4244    case BuiltinType::Char_U:
4245    case BuiltinType::UChar:      return 'C';
4246    case BuiltinType::UShort:     return 'S';
4247    case BuiltinType::UInt:       return 'I';
4248    case BuiltinType::ULong:
4249        return C->getIntWidth(T) == 32 ? 'L' : 'Q';
4250    case BuiltinType::UInt128:    return 'T';
4251    case BuiltinType::ULongLong:  return 'Q';
4252    case BuiltinType::Char_S:
4253    case BuiltinType::SChar:      return 'c';
4254    case BuiltinType::Short:      return 's';
4255    case BuiltinType::WChar_S:
4256    case BuiltinType::WChar_U:
4257    case BuiltinType::Int:        return 'i';
4258    case BuiltinType::Long:
4259      return C->getIntWidth(T) == 32 ? 'l' : 'q';
4260    case BuiltinType::LongLong:   return 'q';
4261    case BuiltinType::Int128:     return 't';
4262    case BuiltinType::Float:      return 'f';
4263    case BuiltinType::Double:     return 'd';
4264    case BuiltinType::LongDouble: return 'D';
4265    }
4266}
4267
4268static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
4269  EnumDecl *Enum = ET->getDecl();
4270
4271  // The encoding of an non-fixed enum type is always 'i', regardless of size.
4272  if (!Enum->isFixed())
4273    return 'i';
4274
4275  // The encoding of a fixed enum type matches its fixed underlying type.
4276  return ObjCEncodingForPrimitiveKind(C, Enum->getIntegerType());
4277}
4278
4279static void EncodeBitField(const ASTContext *Ctx, std::string& S,
4280                           QualType T, const FieldDecl *FD) {
4281  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
4282  S += 'b';
4283  // The NeXT runtime encodes bit fields as b followed by the number of bits.
4284  // The GNU runtime requires more information; bitfields are encoded as b,
4285  // then the offset (in bits) of the first element, then the type of the
4286  // bitfield, then the size in bits.  For example, in this structure:
4287  //
4288  // struct
4289  // {
4290  //    int integer;
4291  //    int flags:2;
4292  // };
4293  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
4294  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
4295  // information is not especially sensible, but we're stuck with it for
4296  // compatibility with GCC, although providing it breaks anything that
4297  // actually uses runtime introspection and wants to work on both runtimes...
4298  if (!Ctx->getLangOptions().NeXTRuntime) {
4299    const RecordDecl *RD = FD->getParent();
4300    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
4301    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
4302    if (const EnumType *ET = T->getAs<EnumType>())
4303      S += ObjCEncodingForEnumType(Ctx, ET);
4304    else
4305      S += ObjCEncodingForPrimitiveKind(Ctx, T);
4306  }
4307  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
4308}
4309
4310// FIXME: Use SmallString for accumulating string.
4311void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
4312                                            bool ExpandPointedToStructures,
4313                                            bool ExpandStructures,
4314                                            const FieldDecl *FD,
4315                                            bool OutermostType,
4316                                            bool EncodingProperty,
4317                                            bool StructField) const {
4318  if (T->getAs<BuiltinType>()) {
4319    if (FD && FD->isBitField())
4320      return EncodeBitField(this, S, T, FD);
4321    S += ObjCEncodingForPrimitiveKind(this, T);
4322    return;
4323  }
4324
4325  if (const ComplexType *CT = T->getAs<ComplexType>()) {
4326    S += 'j';
4327    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
4328                               false);
4329    return;
4330  }
4331
4332  // encoding for pointer or r3eference types.
4333  QualType PointeeTy;
4334  if (const PointerType *PT = T->getAs<PointerType>()) {
4335    if (PT->isObjCSelType()) {
4336      S += ':';
4337      return;
4338    }
4339    PointeeTy = PT->getPointeeType();
4340  }
4341  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4342    PointeeTy = RT->getPointeeType();
4343  if (!PointeeTy.isNull()) {
4344    bool isReadOnly = false;
4345    // For historical/compatibility reasons, the read-only qualifier of the
4346    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
4347    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
4348    // Also, do not emit the 'r' for anything but the outermost type!
4349    if (isa<TypedefType>(T.getTypePtr())) {
4350      if (OutermostType && T.isConstQualified()) {
4351        isReadOnly = true;
4352        S += 'r';
4353      }
4354    } else if (OutermostType) {
4355      QualType P = PointeeTy;
4356      while (P->getAs<PointerType>())
4357        P = P->getAs<PointerType>()->getPointeeType();
4358      if (P.isConstQualified()) {
4359        isReadOnly = true;
4360        S += 'r';
4361      }
4362    }
4363    if (isReadOnly) {
4364      // Another legacy compatibility encoding. Some ObjC qualifier and type
4365      // combinations need to be rearranged.
4366      // Rewrite "in const" from "nr" to "rn"
4367      if (StringRef(S).endswith("nr"))
4368        S.replace(S.end()-2, S.end(), "rn");
4369    }
4370
4371    if (PointeeTy->isCharType()) {
4372      // char pointer types should be encoded as '*' unless it is a
4373      // type that has been typedef'd to 'BOOL'.
4374      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
4375        S += '*';
4376        return;
4377      }
4378    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
4379      // GCC binary compat: Need to convert "struct objc_class *" to "#".
4380      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
4381        S += '#';
4382        return;
4383      }
4384      // GCC binary compat: Need to convert "struct objc_object *" to "@".
4385      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
4386        S += '@';
4387        return;
4388      }
4389      // fall through...
4390    }
4391    S += '^';
4392    getLegacyIntegralTypeEncoding(PointeeTy);
4393
4394    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
4395                               NULL);
4396    return;
4397  }
4398
4399  if (const ArrayType *AT =
4400      // Ignore type qualifiers etc.
4401        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
4402    if (isa<IncompleteArrayType>(AT) && !StructField) {
4403      // Incomplete arrays are encoded as a pointer to the array element.
4404      S += '^';
4405
4406      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4407                                 false, ExpandStructures, FD);
4408    } else {
4409      S += '[';
4410
4411      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
4412        if (getTypeSize(CAT->getElementType()) == 0)
4413          S += '0';
4414        else
4415          S += llvm::utostr(CAT->getSize().getZExtValue());
4416      } else {
4417        //Variable length arrays are encoded as a regular array with 0 elements.
4418        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
4419               "Unknown array type!");
4420        S += '0';
4421      }
4422
4423      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4424                                 false, ExpandStructures, FD);
4425      S += ']';
4426    }
4427    return;
4428  }
4429
4430  if (T->getAs<FunctionType>()) {
4431    S += '?';
4432    return;
4433  }
4434
4435  if (const RecordType *RTy = T->getAs<RecordType>()) {
4436    RecordDecl *RDecl = RTy->getDecl();
4437    S += RDecl->isUnion() ? '(' : '{';
4438    // Anonymous structures print as '?'
4439    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
4440      S += II->getName();
4441      if (ClassTemplateSpecializationDecl *Spec
4442          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
4443        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
4444        std::string TemplateArgsStr
4445          = TemplateSpecializationType::PrintTemplateArgumentList(
4446                                            TemplateArgs.data(),
4447                                            TemplateArgs.size(),
4448                                            (*this).getPrintingPolicy());
4449
4450        S += TemplateArgsStr;
4451      }
4452    } else {
4453      S += '?';
4454    }
4455    if (ExpandStructures) {
4456      S += '=';
4457      if (!RDecl->isUnion()) {
4458        getObjCEncodingForStructureImpl(RDecl, S, FD);
4459      } else {
4460        for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4461                                     FieldEnd = RDecl->field_end();
4462             Field != FieldEnd; ++Field) {
4463          if (FD) {
4464            S += '"';
4465            S += Field->getNameAsString();
4466            S += '"';
4467          }
4468
4469          // Special case bit-fields.
4470          if (Field->isBitField()) {
4471            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
4472                                       (*Field));
4473          } else {
4474            QualType qt = Field->getType();
4475            getLegacyIntegralTypeEncoding(qt);
4476            getObjCEncodingForTypeImpl(qt, S, false, true,
4477                                       FD, /*OutermostType*/false,
4478                                       /*EncodingProperty*/false,
4479                                       /*StructField*/true);
4480          }
4481        }
4482      }
4483    }
4484    S += RDecl->isUnion() ? ')' : '}';
4485    return;
4486  }
4487
4488  if (const EnumType *ET = T->getAs<EnumType>()) {
4489    if (FD && FD->isBitField())
4490      EncodeBitField(this, S, T, FD);
4491    else
4492      S += ObjCEncodingForEnumType(this, ET);
4493    return;
4494  }
4495
4496  if (T->isBlockPointerType()) {
4497    S += "@?"; // Unlike a pointer-to-function, which is "^?".
4498    return;
4499  }
4500
4501  // Ignore protocol qualifiers when mangling at this level.
4502  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
4503    T = OT->getBaseType();
4504
4505  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
4506    // @encode(class_name)
4507    ObjCInterfaceDecl *OI = OIT->getDecl();
4508    S += '{';
4509    const IdentifierInfo *II = OI->getIdentifier();
4510    S += II->getName();
4511    S += '=';
4512    SmallVector<const ObjCIvarDecl*, 32> Ivars;
4513    DeepCollectObjCIvars(OI, true, Ivars);
4514    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
4515      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
4516      if (Field->isBitField())
4517        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
4518      else
4519        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
4520    }
4521    S += '}';
4522    return;
4523  }
4524
4525  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
4526    if (OPT->isObjCIdType()) {
4527      S += '@';
4528      return;
4529    }
4530
4531    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
4532      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
4533      // Since this is a binary compatibility issue, need to consult with runtime
4534      // folks. Fortunately, this is a *very* obsure construct.
4535      S += '#';
4536      return;
4537    }
4538
4539    if (OPT->isObjCQualifiedIdType()) {
4540      getObjCEncodingForTypeImpl(getObjCIdType(), S,
4541                                 ExpandPointedToStructures,
4542                                 ExpandStructures, FD);
4543      if (FD || EncodingProperty) {
4544        // Note that we do extended encoding of protocol qualifer list
4545        // Only when doing ivar or property encoding.
4546        S += '"';
4547        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4548             E = OPT->qual_end(); I != E; ++I) {
4549          S += '<';
4550          S += (*I)->getNameAsString();
4551          S += '>';
4552        }
4553        S += '"';
4554      }
4555      return;
4556    }
4557
4558    QualType PointeeTy = OPT->getPointeeType();
4559    if (!EncodingProperty &&
4560        isa<TypedefType>(PointeeTy.getTypePtr())) {
4561      // Another historical/compatibility reason.
4562      // We encode the underlying type which comes out as
4563      // {...};
4564      S += '^';
4565      getObjCEncodingForTypeImpl(PointeeTy, S,
4566                                 false, ExpandPointedToStructures,
4567                                 NULL);
4568      return;
4569    }
4570
4571    S += '@';
4572    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
4573      S += '"';
4574      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4575      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4576           E = OPT->qual_end(); I != E; ++I) {
4577        S += '<';
4578        S += (*I)->getNameAsString();
4579        S += '>';
4580      }
4581      S += '"';
4582    }
4583    return;
4584  }
4585
4586  // gcc just blithely ignores member pointers.
4587  // TODO: maybe there should be a mangling for these
4588  if (T->getAs<MemberPointerType>())
4589    return;
4590
4591  if (T->isVectorType()) {
4592    // This matches gcc's encoding, even though technically it is
4593    // insufficient.
4594    // FIXME. We should do a better job than gcc.
4595    return;
4596  }
4597
4598  llvm_unreachable("@encode for type not implemented!");
4599}
4600
4601void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
4602                                                 std::string &S,
4603                                                 const FieldDecl *FD,
4604                                                 bool includeVBases) const {
4605  assert(RDecl && "Expected non-null RecordDecl");
4606  assert(!RDecl->isUnion() && "Should not be called for unions");
4607  if (!RDecl->getDefinition())
4608    return;
4609
4610  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
4611  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
4612  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
4613
4614  if (CXXRec) {
4615    for (CXXRecordDecl::base_class_iterator
4616           BI = CXXRec->bases_begin(),
4617           BE = CXXRec->bases_end(); BI != BE; ++BI) {
4618      if (!BI->isVirtual()) {
4619        CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4620        if (base->isEmpty())
4621          continue;
4622        uint64_t offs = layout.getBaseClassOffsetInBits(base);
4623        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4624                                  std::make_pair(offs, base));
4625      }
4626    }
4627  }
4628
4629  unsigned i = 0;
4630  for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4631                               FieldEnd = RDecl->field_end();
4632       Field != FieldEnd; ++Field, ++i) {
4633    uint64_t offs = layout.getFieldOffset(i);
4634    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4635                              std::make_pair(offs, *Field));
4636  }
4637
4638  if (CXXRec && includeVBases) {
4639    for (CXXRecordDecl::base_class_iterator
4640           BI = CXXRec->vbases_begin(),
4641           BE = CXXRec->vbases_end(); BI != BE; ++BI) {
4642      CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
4643      if (base->isEmpty())
4644        continue;
4645      uint64_t offs = layout.getVBaseClassOffsetInBits(base);
4646      if (FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
4647        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
4648                                  std::make_pair(offs, base));
4649    }
4650  }
4651
4652  CharUnits size;
4653  if (CXXRec) {
4654    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
4655  } else {
4656    size = layout.getSize();
4657  }
4658
4659  uint64_t CurOffs = 0;
4660  std::multimap<uint64_t, NamedDecl *>::iterator
4661    CurLayObj = FieldOrBaseOffsets.begin();
4662
4663  if ((CurLayObj != FieldOrBaseOffsets.end() && CurLayObj->first != 0) ||
4664      (CurLayObj == FieldOrBaseOffsets.end() &&
4665         CXXRec && CXXRec->isDynamicClass())) {
4666    assert(CXXRec && CXXRec->isDynamicClass() &&
4667           "Offset 0 was empty but no VTable ?");
4668    if (FD) {
4669      S += "\"_vptr$";
4670      std::string recname = CXXRec->getNameAsString();
4671      if (recname.empty()) recname = "?";
4672      S += recname;
4673      S += '"';
4674    }
4675    S += "^^?";
4676    CurOffs += getTypeSize(VoidPtrTy);
4677  }
4678
4679  if (!RDecl->hasFlexibleArrayMember()) {
4680    // Mark the end of the structure.
4681    uint64_t offs = toBits(size);
4682    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
4683                              std::make_pair(offs, (NamedDecl*)0));
4684  }
4685
4686  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
4687    assert(CurOffs <= CurLayObj->first);
4688
4689    if (CurOffs < CurLayObj->first) {
4690      uint64_t padding = CurLayObj->first - CurOffs;
4691      // FIXME: There doesn't seem to be a way to indicate in the encoding that
4692      // packing/alignment of members is different that normal, in which case
4693      // the encoding will be out-of-sync with the real layout.
4694      // If the runtime switches to just consider the size of types without
4695      // taking into account alignment, we could make padding explicit in the
4696      // encoding (e.g. using arrays of chars). The encoding strings would be
4697      // longer then though.
4698      CurOffs += padding;
4699    }
4700
4701    NamedDecl *dcl = CurLayObj->second;
4702    if (dcl == 0)
4703      break; // reached end of structure.
4704
4705    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
4706      // We expand the bases without their virtual bases since those are going
4707      // in the initial structure. Note that this differs from gcc which
4708      // expands virtual bases each time one is encountered in the hierarchy,
4709      // making the encoding type bigger than it really is.
4710      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false);
4711      assert(!base->isEmpty());
4712      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
4713    } else {
4714      FieldDecl *field = cast<FieldDecl>(dcl);
4715      if (FD) {
4716        S += '"';
4717        S += field->getNameAsString();
4718        S += '"';
4719      }
4720
4721      if (field->isBitField()) {
4722        EncodeBitField(this, S, field->getType(), field);
4723        CurOffs += field->getBitWidthValue(*this);
4724      } else {
4725        QualType qt = field->getType();
4726        getLegacyIntegralTypeEncoding(qt);
4727        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
4728                                   /*OutermostType*/false,
4729                                   /*EncodingProperty*/false,
4730                                   /*StructField*/true);
4731        CurOffs += getTypeSize(field->getType());
4732      }
4733    }
4734  }
4735}
4736
4737void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4738                                                 std::string& S) const {
4739  if (QT & Decl::OBJC_TQ_In)
4740    S += 'n';
4741  if (QT & Decl::OBJC_TQ_Inout)
4742    S += 'N';
4743  if (QT & Decl::OBJC_TQ_Out)
4744    S += 'o';
4745  if (QT & Decl::OBJC_TQ_Bycopy)
4746    S += 'O';
4747  if (QT & Decl::OBJC_TQ_Byref)
4748    S += 'R';
4749  if (QT & Decl::OBJC_TQ_Oneway)
4750    S += 'V';
4751}
4752
4753void ASTContext::setBuiltinVaListType(QualType T) {
4754  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4755
4756  BuiltinVaListType = T;
4757}
4758
4759TypedefDecl *ASTContext::getObjCIdDecl() const {
4760  if (!ObjCIdDecl) {
4761    QualType T = getObjCObjectType(ObjCBuiltinIdTy, 0, 0);
4762    T = getObjCObjectPointerType(T);
4763    TypeSourceInfo *IdInfo = getTrivialTypeSourceInfo(T);
4764    ObjCIdDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4765                                     getTranslationUnitDecl(),
4766                                     SourceLocation(), SourceLocation(),
4767                                     &Idents.get("id"), IdInfo);
4768  }
4769
4770  return ObjCIdDecl;
4771}
4772
4773TypedefDecl *ASTContext::getObjCSelDecl() const {
4774  if (!ObjCSelDecl) {
4775    QualType SelT = getPointerType(ObjCBuiltinSelTy);
4776    TypeSourceInfo *SelInfo = getTrivialTypeSourceInfo(SelT);
4777    ObjCSelDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4778                                      getTranslationUnitDecl(),
4779                                      SourceLocation(), SourceLocation(),
4780                                      &Idents.get("SEL"), SelInfo);
4781  }
4782  return ObjCSelDecl;
4783}
4784
4785void ASTContext::setObjCProtoType(QualType QT) {
4786  ObjCProtoType = QT;
4787}
4788
4789TypedefDecl *ASTContext::getObjCClassDecl() const {
4790  if (!ObjCClassDecl) {
4791    QualType T = getObjCObjectType(ObjCBuiltinClassTy, 0, 0);
4792    T = getObjCObjectPointerType(T);
4793    TypeSourceInfo *ClassInfo = getTrivialTypeSourceInfo(T);
4794    ObjCClassDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
4795                                        getTranslationUnitDecl(),
4796                                        SourceLocation(), SourceLocation(),
4797                                        &Idents.get("Class"), ClassInfo);
4798  }
4799
4800  return ObjCClassDecl;
4801}
4802
4803void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4804  assert(ObjCConstantStringType.isNull() &&
4805         "'NSConstantString' type already set!");
4806
4807  ObjCConstantStringType = getObjCInterfaceType(Decl);
4808}
4809
4810/// \brief Retrieve the template name that corresponds to a non-empty
4811/// lookup.
4812TemplateName
4813ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4814                                      UnresolvedSetIterator End) const {
4815  unsigned size = End - Begin;
4816  assert(size > 1 && "set is not overloaded!");
4817
4818  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4819                          size * sizeof(FunctionTemplateDecl*));
4820  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4821
4822  NamedDecl **Storage = OT->getStorage();
4823  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4824    NamedDecl *D = *I;
4825    assert(isa<FunctionTemplateDecl>(D) ||
4826           (isa<UsingShadowDecl>(D) &&
4827            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4828    *Storage++ = D;
4829  }
4830
4831  return TemplateName(OT);
4832}
4833
4834/// \brief Retrieve the template name that represents a qualified
4835/// template name such as \c std::vector.
4836TemplateName
4837ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4838                                     bool TemplateKeyword,
4839                                     TemplateDecl *Template) const {
4840  assert(NNS && "Missing nested-name-specifier in qualified template name");
4841
4842  // FIXME: Canonicalization?
4843  llvm::FoldingSetNodeID ID;
4844  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4845
4846  void *InsertPos = 0;
4847  QualifiedTemplateName *QTN =
4848    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4849  if (!QTN) {
4850    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4851    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4852  }
4853
4854  return TemplateName(QTN);
4855}
4856
4857/// \brief Retrieve the template name that represents a dependent
4858/// template name such as \c MetaFun::template apply.
4859TemplateName
4860ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4861                                     const IdentifierInfo *Name) const {
4862  assert((!NNS || NNS->isDependent()) &&
4863         "Nested name specifier must be dependent");
4864
4865  llvm::FoldingSetNodeID ID;
4866  DependentTemplateName::Profile(ID, NNS, Name);
4867
4868  void *InsertPos = 0;
4869  DependentTemplateName *QTN =
4870    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4871
4872  if (QTN)
4873    return TemplateName(QTN);
4874
4875  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4876  if (CanonNNS == NNS) {
4877    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4878  } else {
4879    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4880    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4881    DependentTemplateName *CheckQTN =
4882      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4883    assert(!CheckQTN && "Dependent type name canonicalization broken");
4884    (void)CheckQTN;
4885  }
4886
4887  DependentTemplateNames.InsertNode(QTN, InsertPos);
4888  return TemplateName(QTN);
4889}
4890
4891/// \brief Retrieve the template name that represents a dependent
4892/// template name such as \c MetaFun::template operator+.
4893TemplateName
4894ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4895                                     OverloadedOperatorKind Operator) const {
4896  assert((!NNS || NNS->isDependent()) &&
4897         "Nested name specifier must be dependent");
4898
4899  llvm::FoldingSetNodeID ID;
4900  DependentTemplateName::Profile(ID, NNS, Operator);
4901
4902  void *InsertPos = 0;
4903  DependentTemplateName *QTN
4904    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4905
4906  if (QTN)
4907    return TemplateName(QTN);
4908
4909  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4910  if (CanonNNS == NNS) {
4911    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4912  } else {
4913    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4914    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4915
4916    DependentTemplateName *CheckQTN
4917      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4918    assert(!CheckQTN && "Dependent template name canonicalization broken");
4919    (void)CheckQTN;
4920  }
4921
4922  DependentTemplateNames.InsertNode(QTN, InsertPos);
4923  return TemplateName(QTN);
4924}
4925
4926TemplateName
4927ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
4928                                         TemplateName replacement) const {
4929  llvm::FoldingSetNodeID ID;
4930  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
4931
4932  void *insertPos = 0;
4933  SubstTemplateTemplateParmStorage *subst
4934    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
4935
4936  if (!subst) {
4937    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
4938    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
4939  }
4940
4941  return TemplateName(subst);
4942}
4943
4944TemplateName
4945ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
4946                                       const TemplateArgument &ArgPack) const {
4947  ASTContext &Self = const_cast<ASTContext &>(*this);
4948  llvm::FoldingSetNodeID ID;
4949  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
4950
4951  void *InsertPos = 0;
4952  SubstTemplateTemplateParmPackStorage *Subst
4953    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
4954
4955  if (!Subst) {
4956    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
4957                                                           ArgPack.pack_size(),
4958                                                         ArgPack.pack_begin());
4959    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
4960  }
4961
4962  return TemplateName(Subst);
4963}
4964
4965/// getFromTargetType - Given one of the integer types provided by
4966/// TargetInfo, produce the corresponding type. The unsigned @p Type
4967/// is actually a value of type @c TargetInfo::IntType.
4968CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4969  switch (Type) {
4970  case TargetInfo::NoInt: return CanQualType();
4971  case TargetInfo::SignedShort: return ShortTy;
4972  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4973  case TargetInfo::SignedInt: return IntTy;
4974  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4975  case TargetInfo::SignedLong: return LongTy;
4976  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4977  case TargetInfo::SignedLongLong: return LongLongTy;
4978  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4979  }
4980
4981  llvm_unreachable("Unhandled TargetInfo::IntType value");
4982}
4983
4984//===----------------------------------------------------------------------===//
4985//                        Type Predicates.
4986//===----------------------------------------------------------------------===//
4987
4988/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4989/// garbage collection attribute.
4990///
4991Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
4992  if (getLangOptions().getGC() == LangOptions::NonGC)
4993    return Qualifiers::GCNone;
4994
4995  assert(getLangOptions().ObjC1);
4996  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
4997
4998  // Default behaviour under objective-C's gc is for ObjC pointers
4999  // (or pointers to them) be treated as though they were declared
5000  // as __strong.
5001  if (GCAttrs == Qualifiers::GCNone) {
5002    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
5003      return Qualifiers::Strong;
5004    else if (Ty->isPointerType())
5005      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
5006  } else {
5007    // It's not valid to set GC attributes on anything that isn't a
5008    // pointer.
5009#ifndef NDEBUG
5010    QualType CT = Ty->getCanonicalTypeInternal();
5011    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
5012      CT = AT->getElementType();
5013    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
5014#endif
5015  }
5016  return GCAttrs;
5017}
5018
5019//===----------------------------------------------------------------------===//
5020//                        Type Compatibility Testing
5021//===----------------------------------------------------------------------===//
5022
5023/// areCompatVectorTypes - Return true if the two specified vector types are
5024/// compatible.
5025static bool areCompatVectorTypes(const VectorType *LHS,
5026                                 const VectorType *RHS) {
5027  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
5028  return LHS->getElementType() == RHS->getElementType() &&
5029         LHS->getNumElements() == RHS->getNumElements();
5030}
5031
5032bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
5033                                          QualType SecondVec) {
5034  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
5035  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
5036
5037  if (hasSameUnqualifiedType(FirstVec, SecondVec))
5038    return true;
5039
5040  // Treat Neon vector types and most AltiVec vector types as if they are the
5041  // equivalent GCC vector types.
5042  const VectorType *First = FirstVec->getAs<VectorType>();
5043  const VectorType *Second = SecondVec->getAs<VectorType>();
5044  if (First->getNumElements() == Second->getNumElements() &&
5045      hasSameType(First->getElementType(), Second->getElementType()) &&
5046      First->getVectorKind() != VectorType::AltiVecPixel &&
5047      First->getVectorKind() != VectorType::AltiVecBool &&
5048      Second->getVectorKind() != VectorType::AltiVecPixel &&
5049      Second->getVectorKind() != VectorType::AltiVecBool)
5050    return true;
5051
5052  return false;
5053}
5054
5055//===----------------------------------------------------------------------===//
5056// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
5057//===----------------------------------------------------------------------===//
5058
5059/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
5060/// inheritance hierarchy of 'rProto'.
5061bool
5062ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
5063                                           ObjCProtocolDecl *rProto) const {
5064  if (lProto == rProto)
5065    return true;
5066  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
5067       E = rProto->protocol_end(); PI != E; ++PI)
5068    if (ProtocolCompatibleWithProtocol(lProto, *PI))
5069      return true;
5070  return false;
5071}
5072
5073/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
5074/// return true if lhs's protocols conform to rhs's protocol; false
5075/// otherwise.
5076bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
5077  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
5078    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
5079  return false;
5080}
5081
5082/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
5083/// Class<p1, ...>.
5084bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
5085                                                      QualType rhs) {
5086  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
5087  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5088  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
5089
5090  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5091       E = lhsQID->qual_end(); I != E; ++I) {
5092    bool match = false;
5093    ObjCProtocolDecl *lhsProto = *I;
5094    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5095         E = rhsOPT->qual_end(); J != E; ++J) {
5096      ObjCProtocolDecl *rhsProto = *J;
5097      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
5098        match = true;
5099        break;
5100      }
5101    }
5102    if (!match)
5103      return false;
5104  }
5105  return true;
5106}
5107
5108/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
5109/// ObjCQualifiedIDType.
5110bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
5111                                                   bool compare) {
5112  // Allow id<P..> and an 'id' or void* type in all cases.
5113  if (lhs->isVoidPointerType() ||
5114      lhs->isObjCIdType() || lhs->isObjCClassType())
5115    return true;
5116  else if (rhs->isVoidPointerType() ||
5117           rhs->isObjCIdType() || rhs->isObjCClassType())
5118    return true;
5119
5120  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
5121    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5122
5123    if (!rhsOPT) return false;
5124
5125    if (rhsOPT->qual_empty()) {
5126      // If the RHS is a unqualified interface pointer "NSString*",
5127      // make sure we check the class hierarchy.
5128      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5129        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5130             E = lhsQID->qual_end(); I != E; ++I) {
5131          // when comparing an id<P> on lhs with a static type on rhs,
5132          // see if static class implements all of id's protocols, directly or
5133          // through its super class and categories.
5134          if (!rhsID->ClassImplementsProtocol(*I, true))
5135            return false;
5136        }
5137      }
5138      // If there are no qualifiers and no interface, we have an 'id'.
5139      return true;
5140    }
5141    // Both the right and left sides have qualifiers.
5142    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5143         E = lhsQID->qual_end(); I != E; ++I) {
5144      ObjCProtocolDecl *lhsProto = *I;
5145      bool match = false;
5146
5147      // when comparing an id<P> on lhs with a static type on rhs,
5148      // see if static class implements all of id's protocols, directly or
5149      // through its super class and categories.
5150      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5151           E = rhsOPT->qual_end(); J != E; ++J) {
5152        ObjCProtocolDecl *rhsProto = *J;
5153        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5154            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5155          match = true;
5156          break;
5157        }
5158      }
5159      // If the RHS is a qualified interface pointer "NSString<P>*",
5160      // make sure we check the class hierarchy.
5161      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5162        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5163             E = lhsQID->qual_end(); I != E; ++I) {
5164          // when comparing an id<P> on lhs with a static type on rhs,
5165          // see if static class implements all of id's protocols, directly or
5166          // through its super class and categories.
5167          if (rhsID->ClassImplementsProtocol(*I, true)) {
5168            match = true;
5169            break;
5170          }
5171        }
5172      }
5173      if (!match)
5174        return false;
5175    }
5176
5177    return true;
5178  }
5179
5180  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
5181  assert(rhsQID && "One of the LHS/RHS should be id<x>");
5182
5183  if (const ObjCObjectPointerType *lhsOPT =
5184        lhs->getAsObjCInterfacePointerType()) {
5185    // If both the right and left sides have qualifiers.
5186    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
5187         E = lhsOPT->qual_end(); I != E; ++I) {
5188      ObjCProtocolDecl *lhsProto = *I;
5189      bool match = false;
5190
5191      // when comparing an id<P> on rhs with a static type on lhs,
5192      // see if static class implements all of id's protocols, directly or
5193      // through its super class and categories.
5194      // First, lhs protocols in the qualifier list must be found, direct
5195      // or indirect in rhs's qualifier list or it is a mismatch.
5196      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5197           E = rhsQID->qual_end(); J != E; ++J) {
5198        ObjCProtocolDecl *rhsProto = *J;
5199        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5200            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5201          match = true;
5202          break;
5203        }
5204      }
5205      if (!match)
5206        return false;
5207    }
5208
5209    // Static class's protocols, or its super class or category protocols
5210    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
5211    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
5212      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5213      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
5214      // This is rather dubious but matches gcc's behavior. If lhs has
5215      // no type qualifier and its class has no static protocol(s)
5216      // assume that it is mismatch.
5217      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
5218        return false;
5219      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5220           LHSInheritedProtocols.begin(),
5221           E = LHSInheritedProtocols.end(); I != E; ++I) {
5222        bool match = false;
5223        ObjCProtocolDecl *lhsProto = (*I);
5224        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5225             E = rhsQID->qual_end(); J != E; ++J) {
5226          ObjCProtocolDecl *rhsProto = *J;
5227          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5228              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5229            match = true;
5230            break;
5231          }
5232        }
5233        if (!match)
5234          return false;
5235      }
5236    }
5237    return true;
5238  }
5239  return false;
5240}
5241
5242/// canAssignObjCInterfaces - Return true if the two interface types are
5243/// compatible for assignment from RHS to LHS.  This handles validation of any
5244/// protocol qualifiers on the LHS or RHS.
5245///
5246bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
5247                                         const ObjCObjectPointerType *RHSOPT) {
5248  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5249  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5250
5251  // If either type represents the built-in 'id' or 'Class' types, return true.
5252  if (LHS->isObjCUnqualifiedIdOrClass() ||
5253      RHS->isObjCUnqualifiedIdOrClass())
5254    return true;
5255
5256  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
5257    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5258                                             QualType(RHSOPT,0),
5259                                             false);
5260
5261  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
5262    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
5263                                                QualType(RHSOPT,0));
5264
5265  // If we have 2 user-defined types, fall into that path.
5266  if (LHS->getInterface() && RHS->getInterface())
5267    return canAssignObjCInterfaces(LHS, RHS);
5268
5269  return false;
5270}
5271
5272/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
5273/// for providing type-safety for objective-c pointers used to pass/return
5274/// arguments in block literals. When passed as arguments, passing 'A*' where
5275/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
5276/// not OK. For the return type, the opposite is not OK.
5277bool ASTContext::canAssignObjCInterfacesInBlockPointer(
5278                                         const ObjCObjectPointerType *LHSOPT,
5279                                         const ObjCObjectPointerType *RHSOPT,
5280                                         bool BlockReturnType) {
5281  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
5282    return true;
5283
5284  if (LHSOPT->isObjCBuiltinType()) {
5285    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
5286  }
5287
5288  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
5289    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5290                                             QualType(RHSOPT,0),
5291                                             false);
5292
5293  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
5294  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
5295  if (LHS && RHS)  { // We have 2 user-defined types.
5296    if (LHS != RHS) {
5297      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
5298        return BlockReturnType;
5299      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
5300        return !BlockReturnType;
5301    }
5302    else
5303      return true;
5304  }
5305  return false;
5306}
5307
5308/// getIntersectionOfProtocols - This routine finds the intersection of set
5309/// of protocols inherited from two distinct objective-c pointer objects.
5310/// It is used to build composite qualifier list of the composite type of
5311/// the conditional expression involving two objective-c pointer objects.
5312static
5313void getIntersectionOfProtocols(ASTContext &Context,
5314                                const ObjCObjectPointerType *LHSOPT,
5315                                const ObjCObjectPointerType *RHSOPT,
5316      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
5317
5318  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5319  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5320  assert(LHS->getInterface() && "LHS must have an interface base");
5321  assert(RHS->getInterface() && "RHS must have an interface base");
5322
5323  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
5324  unsigned LHSNumProtocols = LHS->getNumProtocols();
5325  if (LHSNumProtocols > 0)
5326    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
5327  else {
5328    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5329    Context.CollectInheritedProtocols(LHS->getInterface(),
5330                                      LHSInheritedProtocols);
5331    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
5332                                LHSInheritedProtocols.end());
5333  }
5334
5335  unsigned RHSNumProtocols = RHS->getNumProtocols();
5336  if (RHSNumProtocols > 0) {
5337    ObjCProtocolDecl **RHSProtocols =
5338      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
5339    for (unsigned i = 0; i < RHSNumProtocols; ++i)
5340      if (InheritedProtocolSet.count(RHSProtocols[i]))
5341        IntersectionOfProtocols.push_back(RHSProtocols[i]);
5342  } else {
5343    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
5344    Context.CollectInheritedProtocols(RHS->getInterface(),
5345                                      RHSInheritedProtocols);
5346    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5347         RHSInheritedProtocols.begin(),
5348         E = RHSInheritedProtocols.end(); I != E; ++I)
5349      if (InheritedProtocolSet.count((*I)))
5350        IntersectionOfProtocols.push_back((*I));
5351  }
5352}
5353
5354/// areCommonBaseCompatible - Returns common base class of the two classes if
5355/// one found. Note that this is O'2 algorithm. But it will be called as the
5356/// last type comparison in a ?-exp of ObjC pointer types before a
5357/// warning is issued. So, its invokation is extremely rare.
5358QualType ASTContext::areCommonBaseCompatible(
5359                                          const ObjCObjectPointerType *Lptr,
5360                                          const ObjCObjectPointerType *Rptr) {
5361  const ObjCObjectType *LHS = Lptr->getObjectType();
5362  const ObjCObjectType *RHS = Rptr->getObjectType();
5363  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
5364  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
5365  if (!LDecl || !RDecl || (LDecl == RDecl))
5366    return QualType();
5367
5368  do {
5369    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
5370    if (canAssignObjCInterfaces(LHS, RHS)) {
5371      SmallVector<ObjCProtocolDecl *, 8> Protocols;
5372      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
5373
5374      QualType Result = QualType(LHS, 0);
5375      if (!Protocols.empty())
5376        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
5377      Result = getObjCObjectPointerType(Result);
5378      return Result;
5379    }
5380  } while ((LDecl = LDecl->getSuperClass()));
5381
5382  return QualType();
5383}
5384
5385bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
5386                                         const ObjCObjectType *RHS) {
5387  assert(LHS->getInterface() && "LHS is not an interface type");
5388  assert(RHS->getInterface() && "RHS is not an interface type");
5389
5390  // Verify that the base decls are compatible: the RHS must be a subclass of
5391  // the LHS.
5392  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
5393    return false;
5394
5395  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
5396  // protocol qualified at all, then we are good.
5397  if (LHS->getNumProtocols() == 0)
5398    return true;
5399
5400  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't,
5401  // more detailed analysis is required.
5402  if (RHS->getNumProtocols() == 0) {
5403    // OK, if LHS is a superclass of RHS *and*
5404    // this superclass is assignment compatible with LHS.
5405    // false otherwise.
5406    bool IsSuperClass =
5407      LHS->getInterface()->isSuperClassOf(RHS->getInterface());
5408    if (IsSuperClass) {
5409      // OK if conversion of LHS to SuperClass results in narrowing of types
5410      // ; i.e., SuperClass may implement at least one of the protocols
5411      // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
5412      // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
5413      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
5414      CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
5415      // If super class has no protocols, it is not a match.
5416      if (SuperClassInheritedProtocols.empty())
5417        return false;
5418
5419      for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5420           LHSPE = LHS->qual_end();
5421           LHSPI != LHSPE; LHSPI++) {
5422        bool SuperImplementsProtocol = false;
5423        ObjCProtocolDecl *LHSProto = (*LHSPI);
5424
5425        for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5426             SuperClassInheritedProtocols.begin(),
5427             E = SuperClassInheritedProtocols.end(); I != E; ++I) {
5428          ObjCProtocolDecl *SuperClassProto = (*I);
5429          if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
5430            SuperImplementsProtocol = true;
5431            break;
5432          }
5433        }
5434        if (!SuperImplementsProtocol)
5435          return false;
5436      }
5437      return true;
5438    }
5439    return false;
5440  }
5441
5442  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
5443                                     LHSPE = LHS->qual_end();
5444       LHSPI != LHSPE; LHSPI++) {
5445    bool RHSImplementsProtocol = false;
5446
5447    // If the RHS doesn't implement the protocol on the left, the types
5448    // are incompatible.
5449    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
5450                                       RHSPE = RHS->qual_end();
5451         RHSPI != RHSPE; RHSPI++) {
5452      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
5453        RHSImplementsProtocol = true;
5454        break;
5455      }
5456    }
5457    // FIXME: For better diagnostics, consider passing back the protocol name.
5458    if (!RHSImplementsProtocol)
5459      return false;
5460  }
5461  // The RHS implements all protocols listed on the LHS.
5462  return true;
5463}
5464
5465bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
5466  // get the "pointed to" types
5467  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
5468  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
5469
5470  if (!LHSOPT || !RHSOPT)
5471    return false;
5472
5473  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
5474         canAssignObjCInterfaces(RHSOPT, LHSOPT);
5475}
5476
5477bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
5478  return canAssignObjCInterfaces(
5479                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
5480                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
5481}
5482
5483/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
5484/// both shall have the identically qualified version of a compatible type.
5485/// C99 6.2.7p1: Two types have compatible types if their types are the
5486/// same. See 6.7.[2,3,5] for additional rules.
5487bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
5488                                    bool CompareUnqualified) {
5489  if (getLangOptions().CPlusPlus)
5490    return hasSameType(LHS, RHS);
5491
5492  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
5493}
5494
5495bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
5496  return typesAreCompatible(LHS, RHS);
5497}
5498
5499bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
5500  return !mergeTypes(LHS, RHS, true).isNull();
5501}
5502
5503/// mergeTransparentUnionType - if T is a transparent union type and a member
5504/// of T is compatible with SubType, return the merged type, else return
5505/// QualType()
5506QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
5507                                               bool OfBlockPointer,
5508                                               bool Unqualified) {
5509  if (const RecordType *UT = T->getAsUnionType()) {
5510    RecordDecl *UD = UT->getDecl();
5511    if (UD->hasAttr<TransparentUnionAttr>()) {
5512      for (RecordDecl::field_iterator it = UD->field_begin(),
5513           itend = UD->field_end(); it != itend; ++it) {
5514        QualType ET = it->getType().getUnqualifiedType();
5515        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
5516        if (!MT.isNull())
5517          return MT;
5518      }
5519    }
5520  }
5521
5522  return QualType();
5523}
5524
5525/// mergeFunctionArgumentTypes - merge two types which appear as function
5526/// argument types
5527QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
5528                                                bool OfBlockPointer,
5529                                                bool Unqualified) {
5530  // GNU extension: two types are compatible if they appear as a function
5531  // argument, one of the types is a transparent union type and the other
5532  // type is compatible with a union member
5533  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
5534                                              Unqualified);
5535  if (!lmerge.isNull())
5536    return lmerge;
5537
5538  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
5539                                              Unqualified);
5540  if (!rmerge.isNull())
5541    return rmerge;
5542
5543  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
5544}
5545
5546QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
5547                                        bool OfBlockPointer,
5548                                        bool Unqualified) {
5549  const FunctionType *lbase = lhs->getAs<FunctionType>();
5550  const FunctionType *rbase = rhs->getAs<FunctionType>();
5551  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
5552  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
5553  bool allLTypes = true;
5554  bool allRTypes = true;
5555
5556  // Check return type
5557  QualType retType;
5558  if (OfBlockPointer) {
5559    QualType RHS = rbase->getResultType();
5560    QualType LHS = lbase->getResultType();
5561    bool UnqualifiedResult = Unqualified;
5562    if (!UnqualifiedResult)
5563      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
5564    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
5565  }
5566  else
5567    retType = mergeTypes(lbase->getResultType(), rbase->getResultType(), false,
5568                         Unqualified);
5569  if (retType.isNull()) return QualType();
5570
5571  if (Unqualified)
5572    retType = retType.getUnqualifiedType();
5573
5574  CanQualType LRetType = getCanonicalType(lbase->getResultType());
5575  CanQualType RRetType = getCanonicalType(rbase->getResultType());
5576  if (Unqualified) {
5577    LRetType = LRetType.getUnqualifiedType();
5578    RRetType = RRetType.getUnqualifiedType();
5579  }
5580
5581  if (getCanonicalType(retType) != LRetType)
5582    allLTypes = false;
5583  if (getCanonicalType(retType) != RRetType)
5584    allRTypes = false;
5585
5586  // FIXME: double check this
5587  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
5588  //                           rbase->getRegParmAttr() != 0 &&
5589  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
5590  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
5591  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
5592
5593  // Compatible functions must have compatible calling conventions
5594  if (!isSameCallConv(lbaseInfo.getCC(), rbaseInfo.getCC()))
5595    return QualType();
5596
5597  // Regparm is part of the calling convention.
5598  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
5599    return QualType();
5600  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
5601    return QualType();
5602
5603  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
5604    return QualType();
5605
5606  // functypes which return are preferred over those that do not.
5607  if (lbaseInfo.getNoReturn() && !rbaseInfo.getNoReturn())
5608    allLTypes = false;
5609  else if (!lbaseInfo.getNoReturn() && rbaseInfo.getNoReturn())
5610    allRTypes = false;
5611  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
5612  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
5613
5614  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
5615
5616  if (lproto && rproto) { // two C99 style function prototypes
5617    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
5618           "C++ shouldn't be here");
5619    unsigned lproto_nargs = lproto->getNumArgs();
5620    unsigned rproto_nargs = rproto->getNumArgs();
5621
5622    // Compatible functions must have the same number of arguments
5623    if (lproto_nargs != rproto_nargs)
5624      return QualType();
5625
5626    // Variadic and non-variadic functions aren't compatible
5627    if (lproto->isVariadic() != rproto->isVariadic())
5628      return QualType();
5629
5630    if (lproto->getTypeQuals() != rproto->getTypeQuals())
5631      return QualType();
5632
5633    if (LangOpts.ObjCAutoRefCount &&
5634        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
5635      return QualType();
5636
5637    // Check argument compatibility
5638    SmallVector<QualType, 10> types;
5639    for (unsigned i = 0; i < lproto_nargs; i++) {
5640      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
5641      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
5642      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
5643                                                    OfBlockPointer,
5644                                                    Unqualified);
5645      if (argtype.isNull()) return QualType();
5646
5647      if (Unqualified)
5648        argtype = argtype.getUnqualifiedType();
5649
5650      types.push_back(argtype);
5651      if (Unqualified) {
5652        largtype = largtype.getUnqualifiedType();
5653        rargtype = rargtype.getUnqualifiedType();
5654      }
5655
5656      if (getCanonicalType(argtype) != getCanonicalType(largtype))
5657        allLTypes = false;
5658      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
5659        allRTypes = false;
5660    }
5661
5662    if (allLTypes) return lhs;
5663    if (allRTypes) return rhs;
5664
5665    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
5666    EPI.ExtInfo = einfo;
5667    return getFunctionType(retType, types.begin(), types.size(), EPI);
5668  }
5669
5670  if (lproto) allRTypes = false;
5671  if (rproto) allLTypes = false;
5672
5673  const FunctionProtoType *proto = lproto ? lproto : rproto;
5674  if (proto) {
5675    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
5676    if (proto->isVariadic()) return QualType();
5677    // Check that the types are compatible with the types that
5678    // would result from default argument promotions (C99 6.7.5.3p15).
5679    // The only types actually affected are promotable integer
5680    // types and floats, which would be passed as a different
5681    // type depending on whether the prototype is visible.
5682    unsigned proto_nargs = proto->getNumArgs();
5683    for (unsigned i = 0; i < proto_nargs; ++i) {
5684      QualType argTy = proto->getArgType(i);
5685
5686      // Look at the promotion type of enum types, since that is the type used
5687      // to pass enum values.
5688      if (const EnumType *Enum = argTy->getAs<EnumType>())
5689        argTy = Enum->getDecl()->getPromotionType();
5690
5691      if (argTy->isPromotableIntegerType() ||
5692          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
5693        return QualType();
5694    }
5695
5696    if (allLTypes) return lhs;
5697    if (allRTypes) return rhs;
5698
5699    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
5700    EPI.ExtInfo = einfo;
5701    return getFunctionType(retType, proto->arg_type_begin(),
5702                           proto->getNumArgs(), EPI);
5703  }
5704
5705  if (allLTypes) return lhs;
5706  if (allRTypes) return rhs;
5707  return getFunctionNoProtoType(retType, einfo);
5708}
5709
5710QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
5711                                bool OfBlockPointer,
5712                                bool Unqualified, bool BlockReturnType) {
5713  // C++ [expr]: If an expression initially has the type "reference to T", the
5714  // type is adjusted to "T" prior to any further analysis, the expression
5715  // designates the object or function denoted by the reference, and the
5716  // expression is an lvalue unless the reference is an rvalue reference and
5717  // the expression is a function call (possibly inside parentheses).
5718  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
5719  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
5720
5721  if (Unqualified) {
5722    LHS = LHS.getUnqualifiedType();
5723    RHS = RHS.getUnqualifiedType();
5724  }
5725
5726  QualType LHSCan = getCanonicalType(LHS),
5727           RHSCan = getCanonicalType(RHS);
5728
5729  // If two types are identical, they are compatible.
5730  if (LHSCan == RHSCan)
5731    return LHS;
5732
5733  // If the qualifiers are different, the types aren't compatible... mostly.
5734  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5735  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5736  if (LQuals != RQuals) {
5737    // If any of these qualifiers are different, we have a type
5738    // mismatch.
5739    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5740        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
5741        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
5742      return QualType();
5743
5744    // Exactly one GC qualifier difference is allowed: __strong is
5745    // okay if the other type has no GC qualifier but is an Objective
5746    // C object pointer (i.e. implicitly strong by default).  We fix
5747    // this by pretending that the unqualified type was actually
5748    // qualified __strong.
5749    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5750    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5751    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5752
5753    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5754      return QualType();
5755
5756    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
5757      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
5758    }
5759    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
5760      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
5761    }
5762    return QualType();
5763  }
5764
5765  // Okay, qualifiers are equal.
5766
5767  Type::TypeClass LHSClass = LHSCan->getTypeClass();
5768  Type::TypeClass RHSClass = RHSCan->getTypeClass();
5769
5770  // We want to consider the two function types to be the same for these
5771  // comparisons, just force one to the other.
5772  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
5773  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
5774
5775  // Same as above for arrays
5776  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
5777    LHSClass = Type::ConstantArray;
5778  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
5779    RHSClass = Type::ConstantArray;
5780
5781  // ObjCInterfaces are just specialized ObjCObjects.
5782  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
5783  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
5784
5785  // Canonicalize ExtVector -> Vector.
5786  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
5787  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
5788
5789  // If the canonical type classes don't match.
5790  if (LHSClass != RHSClass) {
5791    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
5792    // a signed integer type, or an unsigned integer type.
5793    // Compatibility is based on the underlying type, not the promotion
5794    // type.
5795    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
5796      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
5797        return RHS;
5798    }
5799    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
5800      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
5801        return LHS;
5802    }
5803
5804    return QualType();
5805  }
5806
5807  // The canonical type classes match.
5808  switch (LHSClass) {
5809#define TYPE(Class, Base)
5810#define ABSTRACT_TYPE(Class, Base)
5811#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
5812#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
5813#define DEPENDENT_TYPE(Class, Base) case Type::Class:
5814#include "clang/AST/TypeNodes.def"
5815    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
5816
5817  case Type::LValueReference:
5818  case Type::RValueReference:
5819  case Type::MemberPointer:
5820    llvm_unreachable("C++ should never be in mergeTypes");
5821
5822  case Type::ObjCInterface:
5823  case Type::IncompleteArray:
5824  case Type::VariableArray:
5825  case Type::FunctionProto:
5826  case Type::ExtVector:
5827    llvm_unreachable("Types are eliminated above");
5828
5829  case Type::Pointer:
5830  {
5831    // Merge two pointer types, while trying to preserve typedef info
5832    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
5833    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
5834    if (Unqualified) {
5835      LHSPointee = LHSPointee.getUnqualifiedType();
5836      RHSPointee = RHSPointee.getUnqualifiedType();
5837    }
5838    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
5839                                     Unqualified);
5840    if (ResultType.isNull()) return QualType();
5841    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5842      return LHS;
5843    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5844      return RHS;
5845    return getPointerType(ResultType);
5846  }
5847  case Type::BlockPointer:
5848  {
5849    // Merge two block pointer types, while trying to preserve typedef info
5850    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
5851    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
5852    if (Unqualified) {
5853      LHSPointee = LHSPointee.getUnqualifiedType();
5854      RHSPointee = RHSPointee.getUnqualifiedType();
5855    }
5856    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
5857                                     Unqualified);
5858    if (ResultType.isNull()) return QualType();
5859    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5860      return LHS;
5861    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5862      return RHS;
5863    return getBlockPointerType(ResultType);
5864  }
5865  case Type::Atomic:
5866  {
5867    // Merge two pointer types, while trying to preserve typedef info
5868    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
5869    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
5870    if (Unqualified) {
5871      LHSValue = LHSValue.getUnqualifiedType();
5872      RHSValue = RHSValue.getUnqualifiedType();
5873    }
5874    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
5875                                     Unqualified);
5876    if (ResultType.isNull()) return QualType();
5877    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
5878      return LHS;
5879    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
5880      return RHS;
5881    return getAtomicType(ResultType);
5882  }
5883  case Type::ConstantArray:
5884  {
5885    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
5886    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
5887    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
5888      return QualType();
5889
5890    QualType LHSElem = getAsArrayType(LHS)->getElementType();
5891    QualType RHSElem = getAsArrayType(RHS)->getElementType();
5892    if (Unqualified) {
5893      LHSElem = LHSElem.getUnqualifiedType();
5894      RHSElem = RHSElem.getUnqualifiedType();
5895    }
5896
5897    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
5898    if (ResultType.isNull()) return QualType();
5899    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5900      return LHS;
5901    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5902      return RHS;
5903    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
5904                                          ArrayType::ArraySizeModifier(), 0);
5905    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
5906                                          ArrayType::ArraySizeModifier(), 0);
5907    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
5908    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
5909    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5910      return LHS;
5911    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5912      return RHS;
5913    if (LVAT) {
5914      // FIXME: This isn't correct! But tricky to implement because
5915      // the array's size has to be the size of LHS, but the type
5916      // has to be different.
5917      return LHS;
5918    }
5919    if (RVAT) {
5920      // FIXME: This isn't correct! But tricky to implement because
5921      // the array's size has to be the size of RHS, but the type
5922      // has to be different.
5923      return RHS;
5924    }
5925    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
5926    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
5927    return getIncompleteArrayType(ResultType,
5928                                  ArrayType::ArraySizeModifier(), 0);
5929  }
5930  case Type::FunctionNoProto:
5931    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
5932  case Type::Record:
5933  case Type::Enum:
5934    return QualType();
5935  case Type::Builtin:
5936    // Only exactly equal builtin types are compatible, which is tested above.
5937    return QualType();
5938  case Type::Complex:
5939    // Distinct complex types are incompatible.
5940    return QualType();
5941  case Type::Vector:
5942    // FIXME: The merged type should be an ExtVector!
5943    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
5944                             RHSCan->getAs<VectorType>()))
5945      return LHS;
5946    return QualType();
5947  case Type::ObjCObject: {
5948    // Check if the types are assignment compatible.
5949    // FIXME: This should be type compatibility, e.g. whether
5950    // "LHS x; RHS x;" at global scope is legal.
5951    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
5952    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
5953    if (canAssignObjCInterfaces(LHSIface, RHSIface))
5954      return LHS;
5955
5956    return QualType();
5957  }
5958  case Type::ObjCObjectPointer: {
5959    if (OfBlockPointer) {
5960      if (canAssignObjCInterfacesInBlockPointer(
5961                                          LHS->getAs<ObjCObjectPointerType>(),
5962                                          RHS->getAs<ObjCObjectPointerType>(),
5963                                          BlockReturnType))
5964      return LHS;
5965      return QualType();
5966    }
5967    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
5968                                RHS->getAs<ObjCObjectPointerType>()))
5969      return LHS;
5970
5971    return QualType();
5972    }
5973  }
5974
5975  return QualType();
5976}
5977
5978bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
5979                   const FunctionProtoType *FromFunctionType,
5980                   const FunctionProtoType *ToFunctionType) {
5981  if (FromFunctionType->hasAnyConsumedArgs() !=
5982      ToFunctionType->hasAnyConsumedArgs())
5983    return false;
5984  FunctionProtoType::ExtProtoInfo FromEPI =
5985    FromFunctionType->getExtProtoInfo();
5986  FunctionProtoType::ExtProtoInfo ToEPI =
5987    ToFunctionType->getExtProtoInfo();
5988  if (FromEPI.ConsumedArguments && ToEPI.ConsumedArguments)
5989    for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs();
5990         ArgIdx != NumArgs; ++ArgIdx)  {
5991      if (FromEPI.ConsumedArguments[ArgIdx] !=
5992          ToEPI.ConsumedArguments[ArgIdx])
5993        return false;
5994    }
5995  return true;
5996}
5997
5998/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
5999/// 'RHS' attributes and returns the merged version; including for function
6000/// return types.
6001QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
6002  QualType LHSCan = getCanonicalType(LHS),
6003  RHSCan = getCanonicalType(RHS);
6004  // If two types are identical, they are compatible.
6005  if (LHSCan == RHSCan)
6006    return LHS;
6007  if (RHSCan->isFunctionType()) {
6008    if (!LHSCan->isFunctionType())
6009      return QualType();
6010    QualType OldReturnType =
6011      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
6012    QualType NewReturnType =
6013      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
6014    QualType ResReturnType =
6015      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
6016    if (ResReturnType.isNull())
6017      return QualType();
6018    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
6019      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
6020      // In either case, use OldReturnType to build the new function type.
6021      const FunctionType *F = LHS->getAs<FunctionType>();
6022      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
6023        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
6024        EPI.ExtInfo = getFunctionExtInfo(LHS);
6025        QualType ResultType
6026          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
6027                            FPT->getNumArgs(), EPI);
6028        return ResultType;
6029      }
6030    }
6031    return QualType();
6032  }
6033
6034  // If the qualifiers are different, the types can still be merged.
6035  Qualifiers LQuals = LHSCan.getLocalQualifiers();
6036  Qualifiers RQuals = RHSCan.getLocalQualifiers();
6037  if (LQuals != RQuals) {
6038    // If any of these qualifiers are different, we have a type mismatch.
6039    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
6040        LQuals.getAddressSpace() != RQuals.getAddressSpace())
6041      return QualType();
6042
6043    // Exactly one GC qualifier difference is allowed: __strong is
6044    // okay if the other type has no GC qualifier but is an Objective
6045    // C object pointer (i.e. implicitly strong by default).  We fix
6046    // this by pretending that the unqualified type was actually
6047    // qualified __strong.
6048    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
6049    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
6050    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
6051
6052    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
6053      return QualType();
6054
6055    if (GC_L == Qualifiers::Strong)
6056      return LHS;
6057    if (GC_R == Qualifiers::Strong)
6058      return RHS;
6059    return QualType();
6060  }
6061
6062  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
6063    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6064    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6065    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
6066    if (ResQT == LHSBaseQT)
6067      return LHS;
6068    if (ResQT == RHSBaseQT)
6069      return RHS;
6070  }
6071  return QualType();
6072}
6073
6074//===----------------------------------------------------------------------===//
6075//                         Integer Predicates
6076//===----------------------------------------------------------------------===//
6077
6078unsigned ASTContext::getIntWidth(QualType T) const {
6079  if (const EnumType *ET = dyn_cast<EnumType>(T))
6080    T = ET->getDecl()->getIntegerType();
6081  if (T->isBooleanType())
6082    return 1;
6083  // For builtin types, just use the standard type sizing method
6084  return (unsigned)getTypeSize(T);
6085}
6086
6087QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
6088  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
6089
6090  // Turn <4 x signed int> -> <4 x unsigned int>
6091  if (const VectorType *VTy = T->getAs<VectorType>())
6092    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
6093                         VTy->getNumElements(), VTy->getVectorKind());
6094
6095  // For enums, we return the unsigned version of the base type.
6096  if (const EnumType *ETy = T->getAs<EnumType>())
6097    T = ETy->getDecl()->getIntegerType();
6098
6099  const BuiltinType *BTy = T->getAs<BuiltinType>();
6100  assert(BTy && "Unexpected signed integer type");
6101  switch (BTy->getKind()) {
6102  case BuiltinType::Char_S:
6103  case BuiltinType::SChar:
6104    return UnsignedCharTy;
6105  case BuiltinType::Short:
6106    return UnsignedShortTy;
6107  case BuiltinType::Int:
6108    return UnsignedIntTy;
6109  case BuiltinType::Long:
6110    return UnsignedLongTy;
6111  case BuiltinType::LongLong:
6112    return UnsignedLongLongTy;
6113  case BuiltinType::Int128:
6114    return UnsignedInt128Ty;
6115  default:
6116    llvm_unreachable("Unexpected signed integer type");
6117  }
6118}
6119
6120ASTMutationListener::~ASTMutationListener() { }
6121
6122
6123//===----------------------------------------------------------------------===//
6124//                          Builtin Type Computation
6125//===----------------------------------------------------------------------===//
6126
6127/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
6128/// pointer over the consumed characters.  This returns the resultant type.  If
6129/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
6130/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
6131/// a vector of "i*".
6132///
6133/// RequiresICE is filled in on return to indicate whether the value is required
6134/// to be an Integer Constant Expression.
6135static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
6136                                  ASTContext::GetBuiltinTypeError &Error,
6137                                  bool &RequiresICE,
6138                                  bool AllowTypeModifiers) {
6139  // Modifiers.
6140  int HowLong = 0;
6141  bool Signed = false, Unsigned = false;
6142  RequiresICE = false;
6143
6144  // Read the prefixed modifiers first.
6145  bool Done = false;
6146  while (!Done) {
6147    switch (*Str++) {
6148    default: Done = true; --Str; break;
6149    case 'I':
6150      RequiresICE = true;
6151      break;
6152    case 'S':
6153      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
6154      assert(!Signed && "Can't use 'S' modifier multiple times!");
6155      Signed = true;
6156      break;
6157    case 'U':
6158      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
6159      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
6160      Unsigned = true;
6161      break;
6162    case 'L':
6163      assert(HowLong <= 2 && "Can't have LLLL modifier");
6164      ++HowLong;
6165      break;
6166    }
6167  }
6168
6169  QualType Type;
6170
6171  // Read the base type.
6172  switch (*Str++) {
6173  default: llvm_unreachable("Unknown builtin type letter!");
6174  case 'v':
6175    assert(HowLong == 0 && !Signed && !Unsigned &&
6176           "Bad modifiers used with 'v'!");
6177    Type = Context.VoidTy;
6178    break;
6179  case 'f':
6180    assert(HowLong == 0 && !Signed && !Unsigned &&
6181           "Bad modifiers used with 'f'!");
6182    Type = Context.FloatTy;
6183    break;
6184  case 'd':
6185    assert(HowLong < 2 && !Signed && !Unsigned &&
6186           "Bad modifiers used with 'd'!");
6187    if (HowLong)
6188      Type = Context.LongDoubleTy;
6189    else
6190      Type = Context.DoubleTy;
6191    break;
6192  case 's':
6193    assert(HowLong == 0 && "Bad modifiers used with 's'!");
6194    if (Unsigned)
6195      Type = Context.UnsignedShortTy;
6196    else
6197      Type = Context.ShortTy;
6198    break;
6199  case 'i':
6200    if (HowLong == 3)
6201      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
6202    else if (HowLong == 2)
6203      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
6204    else if (HowLong == 1)
6205      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
6206    else
6207      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
6208    break;
6209  case 'c':
6210    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
6211    if (Signed)
6212      Type = Context.SignedCharTy;
6213    else if (Unsigned)
6214      Type = Context.UnsignedCharTy;
6215    else
6216      Type = Context.CharTy;
6217    break;
6218  case 'b': // boolean
6219    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
6220    Type = Context.BoolTy;
6221    break;
6222  case 'z':  // size_t.
6223    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
6224    Type = Context.getSizeType();
6225    break;
6226  case 'F':
6227    Type = Context.getCFConstantStringType();
6228    break;
6229  case 'G':
6230    Type = Context.getObjCIdType();
6231    break;
6232  case 'H':
6233    Type = Context.getObjCSelType();
6234    break;
6235  case 'a':
6236    Type = Context.getBuiltinVaListType();
6237    assert(!Type.isNull() && "builtin va list type not initialized!");
6238    break;
6239  case 'A':
6240    // This is a "reference" to a va_list; however, what exactly
6241    // this means depends on how va_list is defined. There are two
6242    // different kinds of va_list: ones passed by value, and ones
6243    // passed by reference.  An example of a by-value va_list is
6244    // x86, where va_list is a char*. An example of by-ref va_list
6245    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
6246    // we want this argument to be a char*&; for x86-64, we want
6247    // it to be a __va_list_tag*.
6248    Type = Context.getBuiltinVaListType();
6249    assert(!Type.isNull() && "builtin va list type not initialized!");
6250    if (Type->isArrayType())
6251      Type = Context.getArrayDecayedType(Type);
6252    else
6253      Type = Context.getLValueReferenceType(Type);
6254    break;
6255  case 'V': {
6256    char *End;
6257    unsigned NumElements = strtoul(Str, &End, 10);
6258    assert(End != Str && "Missing vector size");
6259    Str = End;
6260
6261    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
6262                                             RequiresICE, false);
6263    assert(!RequiresICE && "Can't require vector ICE");
6264
6265    // TODO: No way to make AltiVec vectors in builtins yet.
6266    Type = Context.getVectorType(ElementType, NumElements,
6267                                 VectorType::GenericVector);
6268    break;
6269  }
6270  case 'X': {
6271    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
6272                                             false);
6273    assert(!RequiresICE && "Can't require complex ICE");
6274    Type = Context.getComplexType(ElementType);
6275    break;
6276  }
6277  case 'Y' : {
6278    Type = Context.getPointerDiffType();
6279    break;
6280  }
6281  case 'P':
6282    Type = Context.getFILEType();
6283    if (Type.isNull()) {
6284      Error = ASTContext::GE_Missing_stdio;
6285      return QualType();
6286    }
6287    break;
6288  case 'J':
6289    if (Signed)
6290      Type = Context.getsigjmp_bufType();
6291    else
6292      Type = Context.getjmp_bufType();
6293
6294    if (Type.isNull()) {
6295      Error = ASTContext::GE_Missing_setjmp;
6296      return QualType();
6297    }
6298    break;
6299  }
6300
6301  // If there are modifiers and if we're allowed to parse them, go for it.
6302  Done = !AllowTypeModifiers;
6303  while (!Done) {
6304    switch (char c = *Str++) {
6305    default: Done = true; --Str; break;
6306    case '*':
6307    case '&': {
6308      // Both pointers and references can have their pointee types
6309      // qualified with an address space.
6310      char *End;
6311      unsigned AddrSpace = strtoul(Str, &End, 10);
6312      if (End != Str && AddrSpace != 0) {
6313        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
6314        Str = End;
6315      }
6316      if (c == '*')
6317        Type = Context.getPointerType(Type);
6318      else
6319        Type = Context.getLValueReferenceType(Type);
6320      break;
6321    }
6322    // FIXME: There's no way to have a built-in with an rvalue ref arg.
6323    case 'C':
6324      Type = Type.withConst();
6325      break;
6326    case 'D':
6327      Type = Context.getVolatileType(Type);
6328      break;
6329    }
6330  }
6331
6332  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
6333         "Integer constant 'I' type must be an integer");
6334
6335  return Type;
6336}
6337
6338/// GetBuiltinType - Return the type for the specified builtin.
6339QualType ASTContext::GetBuiltinType(unsigned Id,
6340                                    GetBuiltinTypeError &Error,
6341                                    unsigned *IntegerConstantArgs) const {
6342  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
6343
6344  SmallVector<QualType, 8> ArgTypes;
6345
6346  bool RequiresICE = false;
6347  Error = GE_None;
6348  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
6349                                       RequiresICE, true);
6350  if (Error != GE_None)
6351    return QualType();
6352
6353  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
6354
6355  while (TypeStr[0] && TypeStr[0] != '.') {
6356    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
6357    if (Error != GE_None)
6358      return QualType();
6359
6360    // If this argument is required to be an IntegerConstantExpression and the
6361    // caller cares, fill in the bitmask we return.
6362    if (RequiresICE && IntegerConstantArgs)
6363      *IntegerConstantArgs |= 1 << ArgTypes.size();
6364
6365    // Do array -> pointer decay.  The builtin should use the decayed type.
6366    if (Ty->isArrayType())
6367      Ty = getArrayDecayedType(Ty);
6368
6369    ArgTypes.push_back(Ty);
6370  }
6371
6372  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
6373         "'.' should only occur at end of builtin type list!");
6374
6375  FunctionType::ExtInfo EI;
6376  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
6377
6378  bool Variadic = (TypeStr[0] == '.');
6379
6380  // We really shouldn't be making a no-proto type here, especially in C++.
6381  if (ArgTypes.empty() && Variadic)
6382    return getFunctionNoProtoType(ResType, EI);
6383
6384  FunctionProtoType::ExtProtoInfo EPI;
6385  EPI.ExtInfo = EI;
6386  EPI.Variadic = Variadic;
6387
6388  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(), EPI);
6389}
6390
6391GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
6392  GVALinkage External = GVA_StrongExternal;
6393
6394  Linkage L = FD->getLinkage();
6395  switch (L) {
6396  case NoLinkage:
6397  case InternalLinkage:
6398  case UniqueExternalLinkage:
6399    return GVA_Internal;
6400
6401  case ExternalLinkage:
6402    switch (FD->getTemplateSpecializationKind()) {
6403    case TSK_Undeclared:
6404    case TSK_ExplicitSpecialization:
6405      External = GVA_StrongExternal;
6406      break;
6407
6408    case TSK_ExplicitInstantiationDefinition:
6409      return GVA_ExplicitTemplateInstantiation;
6410
6411    case TSK_ExplicitInstantiationDeclaration:
6412    case TSK_ImplicitInstantiation:
6413      External = GVA_TemplateInstantiation;
6414      break;
6415    }
6416  }
6417
6418  if (!FD->isInlined())
6419    return External;
6420
6421  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
6422    // GNU or C99 inline semantics. Determine whether this symbol should be
6423    // externally visible.
6424    if (FD->isInlineDefinitionExternallyVisible())
6425      return External;
6426
6427    // C99 inline semantics, where the symbol is not externally visible.
6428    return GVA_C99Inline;
6429  }
6430
6431  // C++0x [temp.explicit]p9:
6432  //   [ Note: The intent is that an inline function that is the subject of
6433  //   an explicit instantiation declaration will still be implicitly
6434  //   instantiated when used so that the body can be considered for
6435  //   inlining, but that no out-of-line copy of the inline function would be
6436  //   generated in the translation unit. -- end note ]
6437  if (FD->getTemplateSpecializationKind()
6438                                       == TSK_ExplicitInstantiationDeclaration)
6439    return GVA_C99Inline;
6440
6441  return GVA_CXXInline;
6442}
6443
6444GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
6445  // If this is a static data member, compute the kind of template
6446  // specialization. Otherwise, this variable is not part of a
6447  // template.
6448  TemplateSpecializationKind TSK = TSK_Undeclared;
6449  if (VD->isStaticDataMember())
6450    TSK = VD->getTemplateSpecializationKind();
6451
6452  Linkage L = VD->getLinkage();
6453  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
6454      VD->getType()->getLinkage() == UniqueExternalLinkage)
6455    L = UniqueExternalLinkage;
6456
6457  switch (L) {
6458  case NoLinkage:
6459  case InternalLinkage:
6460  case UniqueExternalLinkage:
6461    return GVA_Internal;
6462
6463  case ExternalLinkage:
6464    switch (TSK) {
6465    case TSK_Undeclared:
6466    case TSK_ExplicitSpecialization:
6467      return GVA_StrongExternal;
6468
6469    case TSK_ExplicitInstantiationDeclaration:
6470      llvm_unreachable("Variable should not be instantiated");
6471      // Fall through to treat this like any other instantiation.
6472
6473    case TSK_ExplicitInstantiationDefinition:
6474      return GVA_ExplicitTemplateInstantiation;
6475
6476    case TSK_ImplicitInstantiation:
6477      return GVA_TemplateInstantiation;
6478    }
6479  }
6480
6481  return GVA_StrongExternal;
6482}
6483
6484bool ASTContext::DeclMustBeEmitted(const Decl *D) {
6485  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
6486    if (!VD->isFileVarDecl())
6487      return false;
6488  } else if (!isa<FunctionDecl>(D))
6489    return false;
6490
6491  // Weak references don't produce any output by themselves.
6492  if (D->hasAttr<WeakRefAttr>())
6493    return false;
6494
6495  // Aliases and used decls are required.
6496  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
6497    return true;
6498
6499  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
6500    // Forward declarations aren't required.
6501    if (!FD->doesThisDeclarationHaveABody())
6502      return FD->doesDeclarationForceExternallyVisibleDefinition();
6503
6504    // Constructors and destructors are required.
6505    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
6506      return true;
6507
6508    // The key function for a class is required.
6509    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
6510      const CXXRecordDecl *RD = MD->getParent();
6511      if (MD->isOutOfLine() && RD->isDynamicClass()) {
6512        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
6513        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
6514          return true;
6515      }
6516    }
6517
6518    GVALinkage Linkage = GetGVALinkageForFunction(FD);
6519
6520    // static, static inline, always_inline, and extern inline functions can
6521    // always be deferred.  Normal inline functions can be deferred in C99/C++.
6522    // Implicit template instantiations can also be deferred in C++.
6523    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
6524        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
6525      return false;
6526    return true;
6527  }
6528
6529  const VarDecl *VD = cast<VarDecl>(D);
6530  assert(VD->isFileVarDecl() && "Expected file scoped var");
6531
6532  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
6533    return false;
6534
6535  // Structs that have non-trivial constructors or destructors are required.
6536
6537  // FIXME: Handle references.
6538  // FIXME: Be more selective about which constructors we care about.
6539  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
6540    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
6541      if (RD->hasDefinition() && !(RD->hasTrivialDefaultConstructor() &&
6542                                   RD->hasTrivialCopyConstructor() &&
6543                                   RD->hasTrivialMoveConstructor() &&
6544                                   RD->hasTrivialDestructor()))
6545        return true;
6546    }
6547  }
6548
6549  GVALinkage L = GetGVALinkageForVariable(VD);
6550  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
6551    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
6552      return false;
6553  }
6554
6555  return true;
6556}
6557
6558CallingConv ASTContext::getDefaultMethodCallConv() {
6559  // Pass through to the C++ ABI object
6560  return ABI->getDefaultMethodCallConv();
6561}
6562
6563bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
6564  // Pass through to the C++ ABI object
6565  return ABI->isNearlyEmpty(RD);
6566}
6567
6568MangleContext *ASTContext::createMangleContext() {
6569  switch (Target->getCXXABI()) {
6570  case CXXABI_ARM:
6571  case CXXABI_Itanium:
6572    return createItaniumMangleContext(*this, getDiagnostics());
6573  case CXXABI_Microsoft:
6574    return createMicrosoftMangleContext(*this, getDiagnostics());
6575  }
6576  llvm_unreachable("Unsupported ABI");
6577}
6578
6579CXXABI::~CXXABI() {}
6580
6581size_t ASTContext::getSideTableAllocatedMemory() const {
6582  return ASTRecordLayouts.getMemorySize()
6583    + llvm::capacity_in_bytes(ObjCLayouts)
6584    + llvm::capacity_in_bytes(KeyFunctions)
6585    + llvm::capacity_in_bytes(ObjCImpls)
6586    + llvm::capacity_in_bytes(BlockVarCopyInits)
6587    + llvm::capacity_in_bytes(DeclAttrs)
6588    + llvm::capacity_in_bytes(InstantiatedFromStaticDataMember)
6589    + llvm::capacity_in_bytes(InstantiatedFromUsingDecl)
6590    + llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl)
6591    + llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl)
6592    + llvm::capacity_in_bytes(OverriddenMethods)
6593    + llvm::capacity_in_bytes(Types)
6594    + llvm::capacity_in_bytes(VariableArrayTypes)
6595    + llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
6596}
6597
6598void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
6599  ParamIndices[D] = index;
6600}
6601
6602unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
6603  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
6604  assert(I != ParamIndices.end() &&
6605         "ParmIndices lacks entry set by ParmVarDecl");
6606  return I->second;
6607}
6608