ASTContext.cpp revision bbc6454bb98d6a6ecbaafa715222c5db834307f2 
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/RecordLayout.h"
24#include "clang/Basic/Builtins.h"
25#include "clang/Basic/SourceManager.h"
26#include "clang/Basic/TargetInfo.h"
27#include "llvm/ADT/SmallString.h"
28#include "llvm/ADT/StringExtras.h"
29#include "llvm/Support/MathExtras.h"
30#include "llvm/Support/raw_ostream.h"
31
32using namespace clang;
33
34unsigned ASTContext::NumImplicitDefaultConstructors;
35unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
36unsigned ASTContext::NumImplicitCopyConstructors;
37unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
38unsigned ASTContext::NumImplicitCopyAssignmentOperators;
39unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
40unsigned ASTContext::NumImplicitDestructors;
41unsigned ASTContext::NumImplicitDestructorsDeclared;
42
43enum FloatingRank {
44  FloatRank, DoubleRank, LongDoubleRank
45};
46
47void
48ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
49                                               TemplateTemplateParmDecl *Parm) {
50  ID.AddInteger(Parm->getDepth());
51  ID.AddInteger(Parm->getPosition());
52  // FIXME: Parameter pack
53
54  TemplateParameterList *Params = Parm->getTemplateParameters();
55  ID.AddInteger(Params->size());
56  for (TemplateParameterList::const_iterator P = Params->begin(),
57                                          PEnd = Params->end();
58       P != PEnd; ++P) {
59    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
60      ID.AddInteger(0);
61      ID.AddBoolean(TTP->isParameterPack());
62      continue;
63    }
64
65    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
66      ID.AddInteger(1);
67      // FIXME: Parameter pack
68      ID.AddPointer(NTTP->getType().getAsOpaquePtr());
69      continue;
70    }
71
72    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
73    ID.AddInteger(2);
74    Profile(ID, TTP);
75  }
76}
77
78TemplateTemplateParmDecl *
79ASTContext::getCanonicalTemplateTemplateParmDecl(
80                                                 TemplateTemplateParmDecl *TTP) {
81  // Check if we already have a canonical template template parameter.
82  llvm::FoldingSetNodeID ID;
83  CanonicalTemplateTemplateParm::Profile(ID, TTP);
84  void *InsertPos = 0;
85  CanonicalTemplateTemplateParm *Canonical
86    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
87  if (Canonical)
88    return Canonical->getParam();
89
90  // Build a canonical template parameter list.
91  TemplateParameterList *Params = TTP->getTemplateParameters();
92  llvm::SmallVector<NamedDecl *, 4> CanonParams;
93  CanonParams.reserve(Params->size());
94  for (TemplateParameterList::const_iterator P = Params->begin(),
95                                          PEnd = Params->end();
96       P != PEnd; ++P) {
97    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
98      CanonParams.push_back(
99                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
100                                               SourceLocation(), TTP->getDepth(),
101                                               TTP->getIndex(), 0, false,
102                                               TTP->isParameterPack()));
103    else if (NonTypeTemplateParmDecl *NTTP
104             = dyn_cast<NonTypeTemplateParmDecl>(*P))
105      CanonParams.push_back(
106            NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
107                                            SourceLocation(), NTTP->getDepth(),
108                                            NTTP->getPosition(), 0,
109                                            getCanonicalType(NTTP->getType()),
110                                            0));
111    else
112      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
113                                           cast<TemplateTemplateParmDecl>(*P)));
114  }
115
116  TemplateTemplateParmDecl *CanonTTP
117    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
118                                       SourceLocation(), TTP->getDepth(),
119                                       TTP->getPosition(), 0,
120                         TemplateParameterList::Create(*this, SourceLocation(),
121                                                       SourceLocation(),
122                                                       CanonParams.data(),
123                                                       CanonParams.size(),
124                                                       SourceLocation()));
125
126  // Get the new insert position for the node we care about.
127  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
128  assert(Canonical == 0 && "Shouldn't be in the map!");
129  (void)Canonical;
130
131  // Create the canonical template template parameter entry.
132  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
133  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
134  return CanonTTP;
135}
136
137ASTContext::ASTContext(const LangOptions& LOpts, SourceManager &SM,
138                       const TargetInfo &t,
139                       IdentifierTable &idents, SelectorTable &sels,
140                       Builtin::Context &builtins,
141                       unsigned size_reserve) :
142  TemplateSpecializationTypes(this_()),
143  DependentTemplateSpecializationTypes(this_()),
144  GlobalNestedNameSpecifier(0), IsInt128Installed(false),
145  CFConstantStringTypeDecl(0), NSConstantStringTypeDecl(0),
146  ObjCFastEnumerationStateTypeDecl(0), FILEDecl(0), jmp_bufDecl(0),
147  sigjmp_bufDecl(0), BlockDescriptorType(0), BlockDescriptorExtendedType(0),
148  NullTypeSourceInfo(QualType()),
149  SourceMgr(SM), LangOpts(LOpts), Target(t),
150  Idents(idents), Selectors(sels),
151  BuiltinInfo(builtins),
152  DeclarationNames(*this),
153  ExternalSource(0), PrintingPolicy(LOpts),
154  LastSDM(0, 0),
155  UniqueBlockByRefTypeID(0), UniqueBlockParmTypeID(0) {
156  ObjCIdRedefinitionType = QualType();
157  ObjCClassRedefinitionType = QualType();
158  ObjCSelRedefinitionType = QualType();
159  if (size_reserve > 0) Types.reserve(size_reserve);
160  TUDecl = TranslationUnitDecl::Create(*this);
161  InitBuiltinTypes();
162}
163
164ASTContext::~ASTContext() {
165  // Release the DenseMaps associated with DeclContext objects.
166  // FIXME: Is this the ideal solution?
167  ReleaseDeclContextMaps();
168
169  // Call all of the deallocation functions.
170  for (unsigned I = 0, N = Deallocations.size(); I != N; ++I)
171    Deallocations[I].first(Deallocations[I].second);
172
173  // Release all of the memory associated with overridden C++ methods.
174  for (llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::iterator
175         OM = OverriddenMethods.begin(), OMEnd = OverriddenMethods.end();
176       OM != OMEnd; ++OM)
177    OM->second.Destroy();
178
179  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
180  // because they can contain DenseMaps.
181  for (llvm::DenseMap<const ObjCContainerDecl*,
182       const ASTRecordLayout*>::iterator
183       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
184    // Increment in loop to prevent using deallocated memory.
185    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
186      R->Destroy(*this);
187
188  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
189       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
190    // Increment in loop to prevent using deallocated memory.
191    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
192      R->Destroy(*this);
193  }
194  }
195
196void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
197  Deallocations.push_back(std::make_pair(Callback, Data));
198}
199
200void
201ASTContext::setExternalSource(llvm::OwningPtr<ExternalASTSource> &Source) {
202  ExternalSource.reset(Source.take());
203}
204
205void ASTContext::PrintStats() const {
206  fprintf(stderr, "*** AST Context Stats:\n");
207  fprintf(stderr, "  %d types total.\n", (int)Types.size());
208
209  unsigned counts[] = {
210#define TYPE(Name, Parent) 0,
211#define ABSTRACT_TYPE(Name, Parent)
212#include "clang/AST/TypeNodes.def"
213    0 // Extra
214  };
215
216  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
217    Type *T = Types[i];
218    counts[(unsigned)T->getTypeClass()]++;
219  }
220
221  unsigned Idx = 0;
222  unsigned TotalBytes = 0;
223#define TYPE(Name, Parent)                                              \
224  if (counts[Idx])                                                      \
225    fprintf(stderr, "    %d %s types\n", (int)counts[Idx], #Name);      \
226  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
227  ++Idx;
228#define ABSTRACT_TYPE(Name, Parent)
229#include "clang/AST/TypeNodes.def"
230
231  fprintf(stderr, "Total bytes = %d\n", int(TotalBytes));
232
233  // Implicit special member functions.
234  fprintf(stderr, "  %u/%u implicit default constructors created\n",
235          NumImplicitDefaultConstructorsDeclared,
236          NumImplicitDefaultConstructors);
237  fprintf(stderr, "  %u/%u implicit copy constructors created\n",
238          NumImplicitCopyConstructorsDeclared,
239          NumImplicitCopyConstructors);
240  fprintf(stderr, "  %u/%u implicit copy assignment operators created\n",
241          NumImplicitCopyAssignmentOperatorsDeclared,
242          NumImplicitCopyAssignmentOperators);
243  fprintf(stderr, "  %u/%u implicit destructors created\n",
244          NumImplicitDestructorsDeclared, NumImplicitDestructors);
245
246  if (ExternalSource.get()) {
247    fprintf(stderr, "\n");
248    ExternalSource->PrintStats();
249  }
250
251  BumpAlloc.PrintStats();
252}
253
254
255void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
256  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
257  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
258  Types.push_back(Ty);
259}
260
261void ASTContext::InitBuiltinTypes() {
262  assert(VoidTy.isNull() && "Context reinitialized?");
263
264  // C99 6.2.5p19.
265  InitBuiltinType(VoidTy,              BuiltinType::Void);
266
267  // C99 6.2.5p2.
268  InitBuiltinType(BoolTy,              BuiltinType::Bool);
269  // C99 6.2.5p3.
270  if (LangOpts.CharIsSigned)
271    InitBuiltinType(CharTy,            BuiltinType::Char_S);
272  else
273    InitBuiltinType(CharTy,            BuiltinType::Char_U);
274  // C99 6.2.5p4.
275  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
276  InitBuiltinType(ShortTy,             BuiltinType::Short);
277  InitBuiltinType(IntTy,               BuiltinType::Int);
278  InitBuiltinType(LongTy,              BuiltinType::Long);
279  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
280
281  // C99 6.2.5p6.
282  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
283  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
284  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
285  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
286  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
287
288  // C99 6.2.5p10.
289  InitBuiltinType(FloatTy,             BuiltinType::Float);
290  InitBuiltinType(DoubleTy,            BuiltinType::Double);
291  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
292
293  // GNU extension, 128-bit integers.
294  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
295  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
296
297  if (LangOpts.CPlusPlus) // C++ 3.9.1p5
298    InitBuiltinType(WCharTy,           BuiltinType::WChar);
299  else // C99
300    WCharTy = getFromTargetType(Target.getWCharType());
301
302  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
303    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
304  else // C99
305    Char16Ty = getFromTargetType(Target.getChar16Type());
306
307  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
308    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
309  else // C99
310    Char32Ty = getFromTargetType(Target.getChar32Type());
311
312  // Placeholder type for functions.
313  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
314
315  // Placeholder type for type-dependent expressions whose type is
316  // completely unknown. No code should ever check a type against
317  // DependentTy and users should never see it; however, it is here to
318  // help diagnose failures to properly check for type-dependent
319  // expressions.
320  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
321
322  // Placeholder type for C++0x auto declarations whose real type has
323  // not yet been deduced.
324  InitBuiltinType(UndeducedAutoTy, BuiltinType::UndeducedAuto);
325
326  // C99 6.2.5p11.
327  FloatComplexTy      = getComplexType(FloatTy);
328  DoubleComplexTy     = getComplexType(DoubleTy);
329  LongDoubleComplexTy = getComplexType(LongDoubleTy);
330
331  BuiltinVaListType = QualType();
332
333  // "Builtin" typedefs set by Sema::ActOnTranslationUnitScope().
334  ObjCIdTypedefType = QualType();
335  ObjCClassTypedefType = QualType();
336  ObjCSelTypedefType = QualType();
337
338  // Builtin types for 'id', 'Class', and 'SEL'.
339  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
340  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
341  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
342
343  ObjCConstantStringType = QualType();
344
345  // void * type
346  VoidPtrTy = getPointerType(VoidTy);
347
348  // nullptr type (C++0x 2.14.7)
349  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
350}
351
352MemberSpecializationInfo *
353ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
354  assert(Var->isStaticDataMember() && "Not a static data member");
355  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
356    = InstantiatedFromStaticDataMember.find(Var);
357  if (Pos == InstantiatedFromStaticDataMember.end())
358    return 0;
359
360  return Pos->second;
361}
362
363void
364ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
365                                                TemplateSpecializationKind TSK,
366                                          SourceLocation PointOfInstantiation) {
367  assert(Inst->isStaticDataMember() && "Not a static data member");
368  assert(Tmpl->isStaticDataMember() && "Not a static data member");
369  assert(!InstantiatedFromStaticDataMember[Inst] &&
370         "Already noted what static data member was instantiated from");
371  InstantiatedFromStaticDataMember[Inst]
372    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
373}
374
375NamedDecl *
376ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
377  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
378    = InstantiatedFromUsingDecl.find(UUD);
379  if (Pos == InstantiatedFromUsingDecl.end())
380    return 0;
381
382  return Pos->second;
383}
384
385void
386ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
387  assert((isa<UsingDecl>(Pattern) ||
388          isa<UnresolvedUsingValueDecl>(Pattern) ||
389          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
390         "pattern decl is not a using decl");
391  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
392  InstantiatedFromUsingDecl[Inst] = Pattern;
393}
394
395UsingShadowDecl *
396ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
397  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
398    = InstantiatedFromUsingShadowDecl.find(Inst);
399  if (Pos == InstantiatedFromUsingShadowDecl.end())
400    return 0;
401
402  return Pos->second;
403}
404
405void
406ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
407                                               UsingShadowDecl *Pattern) {
408  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
409  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
410}
411
412FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
413  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
414    = InstantiatedFromUnnamedFieldDecl.find(Field);
415  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
416    return 0;
417
418  return Pos->second;
419}
420
421void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
422                                                     FieldDecl *Tmpl) {
423  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
424  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
425  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
426         "Already noted what unnamed field was instantiated from");
427
428  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
429}
430
431ASTContext::overridden_cxx_method_iterator
432ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
433  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
434    = OverriddenMethods.find(Method);
435  if (Pos == OverriddenMethods.end())
436    return 0;
437
438  return Pos->second.begin();
439}
440
441ASTContext::overridden_cxx_method_iterator
442ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
443  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
444    = OverriddenMethods.find(Method);
445  if (Pos == OverriddenMethods.end())
446    return 0;
447
448  return Pos->second.end();
449}
450
451unsigned
452ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
453  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
454    = OverriddenMethods.find(Method);
455  if (Pos == OverriddenMethods.end())
456    return 0;
457
458  return Pos->second.size();
459}
460
461void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
462                                     const CXXMethodDecl *Overridden) {
463  OverriddenMethods[Method].push_back(Overridden);
464}
465
466namespace {
467  class BeforeInTranslationUnit
468    : std::binary_function<SourceRange, SourceRange, bool> {
469    SourceManager *SourceMgr;
470
471  public:
472    explicit BeforeInTranslationUnit(SourceManager *SM) : SourceMgr(SM) { }
473
474    bool operator()(SourceRange X, SourceRange Y) {
475      return SourceMgr->isBeforeInTranslationUnit(X.getBegin(), Y.getBegin());
476    }
477  };
478}
479
480//===----------------------------------------------------------------------===//
481//                         Type Sizing and Analysis
482//===----------------------------------------------------------------------===//
483
484/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
485/// scalar floating point type.
486const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
487  const BuiltinType *BT = T->getAs<BuiltinType>();
488  assert(BT && "Not a floating point type!");
489  switch (BT->getKind()) {
490  default: assert(0 && "Not a floating point type!");
491  case BuiltinType::Float:      return Target.getFloatFormat();
492  case BuiltinType::Double:     return Target.getDoubleFormat();
493  case BuiltinType::LongDouble: return Target.getLongDoubleFormat();
494  }
495}
496
497/// getDeclAlign - Return a conservative estimate of the alignment of the
498/// specified decl.  Note that bitfields do not have a valid alignment, so
499/// this method will assert on them.
500/// If @p RefAsPointee, references are treated like their underlying type
501/// (for alignof), else they're treated like pointers (for CodeGen).
502CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) {
503  unsigned Align = Target.getCharWidth();
504
505  if (const AlignedAttr* AA = D->getAttr<AlignedAttr>())
506    Align = std::max(Align, AA->getMaxAlignment());
507
508  if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
509    QualType T = VD->getType();
510    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
511      if (RefAsPointee)
512        T = RT->getPointeeType();
513      else
514        T = getPointerType(RT->getPointeeType());
515    }
516    if (!T->isIncompleteType() && !T->isFunctionType()) {
517      unsigned MinWidth = Target.getLargeArrayMinWidth();
518      unsigned ArrayAlign = Target.getLargeArrayAlign();
519      if (isa<VariableArrayType>(T) && MinWidth != 0)
520        Align = std::max(Align, ArrayAlign);
521      if (ConstantArrayType *CT = dyn_cast<ConstantArrayType>(T)) {
522        unsigned Size = getTypeSize(CT);
523        if (MinWidth != 0 && MinWidth <= Size)
524          Align = std::max(Align, ArrayAlign);
525      }
526      // Incomplete or function types default to 1.
527      while (isa<VariableArrayType>(T) || isa<IncompleteArrayType>(T))
528        T = cast<ArrayType>(T)->getElementType();
529
530      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
531    }
532    if (const FieldDecl *FD = dyn_cast<FieldDecl>(VD)) {
533      // In the case of a field in a packed struct, we want the minimum
534      // of the alignment of the field and the alignment of the struct.
535      Align = std::min(Align,
536        getPreferredTypeAlign(FD->getParent()->getTypeForDecl()));
537    }
538  }
539
540  return CharUnits::fromQuantity(Align / Target.getCharWidth());
541}
542
543std::pair<CharUnits, CharUnits>
544ASTContext::getTypeInfoInChars(const Type *T) {
545  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
546  return std::make_pair(CharUnits::fromQuantity(Info.first / getCharWidth()),
547                        CharUnits::fromQuantity(Info.second / getCharWidth()));
548}
549
550std::pair<CharUnits, CharUnits>
551ASTContext::getTypeInfoInChars(QualType T) {
552  return getTypeInfoInChars(T.getTypePtr());
553}
554
555/// getTypeSize - Return the size of the specified type, in bits.  This method
556/// does not work on incomplete types.
557///
558/// FIXME: Pointers into different addr spaces could have different sizes and
559/// alignment requirements: getPointerInfo should take an AddrSpace, this
560/// should take a QualType, &c.
561std::pair<uint64_t, unsigned>
562ASTContext::getTypeInfo(const Type *T) {
563  uint64_t Width=0;
564  unsigned Align=8;
565  switch (T->getTypeClass()) {
566#define TYPE(Class, Base)
567#define ABSTRACT_TYPE(Class, Base)
568#define NON_CANONICAL_TYPE(Class, Base)
569#define DEPENDENT_TYPE(Class, Base) case Type::Class:
570#include "clang/AST/TypeNodes.def"
571    assert(false && "Should not see dependent types");
572    break;
573
574  case Type::FunctionNoProto:
575  case Type::FunctionProto:
576    // GCC extension: alignof(function) = 32 bits
577    Width = 0;
578    Align = 32;
579    break;
580
581  case Type::IncompleteArray:
582  case Type::VariableArray:
583    Width = 0;
584    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
585    break;
586
587  case Type::ConstantArray: {
588    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
589
590    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
591    Width = EltInfo.first*CAT->getSize().getZExtValue();
592    Align = EltInfo.second;
593    break;
594  }
595  case Type::ExtVector:
596  case Type::Vector: {
597    const VectorType *VT = cast<VectorType>(T);
598    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
599    Width = EltInfo.first*VT->getNumElements();
600    Align = Width;
601    // If the alignment is not a power of 2, round up to the next power of 2.
602    // This happens for non-power-of-2 length vectors.
603    if (Align & (Align-1)) {
604      Align = llvm::NextPowerOf2(Align);
605      Width = llvm::RoundUpToAlignment(Width, Align);
606    }
607    break;
608  }
609
610  case Type::Builtin:
611    switch (cast<BuiltinType>(T)->getKind()) {
612    default: assert(0 && "Unknown builtin type!");
613    case BuiltinType::Void:
614      // GCC extension: alignof(void) = 8 bits.
615      Width = 0;
616      Align = 8;
617      break;
618
619    case BuiltinType::Bool:
620      Width = Target.getBoolWidth();
621      Align = Target.getBoolAlign();
622      break;
623    case BuiltinType::Char_S:
624    case BuiltinType::Char_U:
625    case BuiltinType::UChar:
626    case BuiltinType::SChar:
627      Width = Target.getCharWidth();
628      Align = Target.getCharAlign();
629      break;
630    case BuiltinType::WChar:
631      Width = Target.getWCharWidth();
632      Align = Target.getWCharAlign();
633      break;
634    case BuiltinType::Char16:
635      Width = Target.getChar16Width();
636      Align = Target.getChar16Align();
637      break;
638    case BuiltinType::Char32:
639      Width = Target.getChar32Width();
640      Align = Target.getChar32Align();
641      break;
642    case BuiltinType::UShort:
643    case BuiltinType::Short:
644      Width = Target.getShortWidth();
645      Align = Target.getShortAlign();
646      break;
647    case BuiltinType::UInt:
648    case BuiltinType::Int:
649      Width = Target.getIntWidth();
650      Align = Target.getIntAlign();
651      break;
652    case BuiltinType::ULong:
653    case BuiltinType::Long:
654      Width = Target.getLongWidth();
655      Align = Target.getLongAlign();
656      break;
657    case BuiltinType::ULongLong:
658    case BuiltinType::LongLong:
659      Width = Target.getLongLongWidth();
660      Align = Target.getLongLongAlign();
661      break;
662    case BuiltinType::Int128:
663    case BuiltinType::UInt128:
664      Width = 128;
665      Align = 128; // int128_t is 128-bit aligned on all targets.
666      break;
667    case BuiltinType::Float:
668      Width = Target.getFloatWidth();
669      Align = Target.getFloatAlign();
670      break;
671    case BuiltinType::Double:
672      Width = Target.getDoubleWidth();
673      Align = Target.getDoubleAlign();
674      break;
675    case BuiltinType::LongDouble:
676      Width = Target.getLongDoubleWidth();
677      Align = Target.getLongDoubleAlign();
678      break;
679    case BuiltinType::NullPtr:
680      Width = Target.getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
681      Align = Target.getPointerAlign(0); //   == sizeof(void*)
682      break;
683    case BuiltinType::ObjCId:
684    case BuiltinType::ObjCClass:
685    case BuiltinType::ObjCSel:
686      Width = Target.getPointerWidth(0);
687      Align = Target.getPointerAlign(0);
688      break;
689    }
690    break;
691  case Type::ObjCObjectPointer:
692    Width = Target.getPointerWidth(0);
693    Align = Target.getPointerAlign(0);
694    break;
695  case Type::BlockPointer: {
696    unsigned AS = cast<BlockPointerType>(T)->getPointeeType().getAddressSpace();
697    Width = Target.getPointerWidth(AS);
698    Align = Target.getPointerAlign(AS);
699    break;
700  }
701  case Type::LValueReference:
702  case Type::RValueReference: {
703    // alignof and sizeof should never enter this code path here, so we go
704    // the pointer route.
705    unsigned AS = cast<ReferenceType>(T)->getPointeeType().getAddressSpace();
706    Width = Target.getPointerWidth(AS);
707    Align = Target.getPointerAlign(AS);
708    break;
709  }
710  case Type::Pointer: {
711    unsigned AS = cast<PointerType>(T)->getPointeeType().getAddressSpace();
712    Width = Target.getPointerWidth(AS);
713    Align = Target.getPointerAlign(AS);
714    break;
715  }
716  case Type::MemberPointer: {
717    QualType Pointee = cast<MemberPointerType>(T)->getPointeeType();
718    std::pair<uint64_t, unsigned> PtrDiffInfo =
719      getTypeInfo(getPointerDiffType());
720    Width = PtrDiffInfo.first;
721    if (Pointee->isFunctionType())
722      Width *= 2;
723    Align = PtrDiffInfo.second;
724    break;
725  }
726  case Type::Complex: {
727    // Complex types have the same alignment as their elements, but twice the
728    // size.
729    std::pair<uint64_t, unsigned> EltInfo =
730      getTypeInfo(cast<ComplexType>(T)->getElementType());
731    Width = EltInfo.first*2;
732    Align = EltInfo.second;
733    break;
734  }
735  case Type::ObjCObject:
736    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
737  case Type::ObjCInterface: {
738    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
739    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
740    Width = Layout.getSize();
741    Align = Layout.getAlignment();
742    break;
743  }
744  case Type::Record:
745  case Type::Enum: {
746    const TagType *TT = cast<TagType>(T);
747
748    if (TT->getDecl()->isInvalidDecl()) {
749      Width = 1;
750      Align = 1;
751      break;
752    }
753
754    if (const EnumType *ET = dyn_cast<EnumType>(TT))
755      return getTypeInfo(ET->getDecl()->getIntegerType());
756
757    const RecordType *RT = cast<RecordType>(TT);
758    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
759    Width = Layout.getSize();
760    Align = Layout.getAlignment();
761    break;
762  }
763
764  case Type::SubstTemplateTypeParm:
765    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
766                       getReplacementType().getTypePtr());
767
768  case Type::Typedef: {
769    const TypedefDecl *Typedef = cast<TypedefType>(T)->getDecl();
770    if (const AlignedAttr *Aligned = Typedef->getAttr<AlignedAttr>()) {
771      Align = std::max(Aligned->getMaxAlignment(),
772                       getTypeAlign(Typedef->getUnderlyingType().getTypePtr()));
773      Width = getTypeSize(Typedef->getUnderlyingType().getTypePtr());
774    } else
775      return getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
776    break;
777  }
778
779  case Type::TypeOfExpr:
780    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
781                         .getTypePtr());
782
783  case Type::TypeOf:
784    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
785
786  case Type::Decltype:
787    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
788                        .getTypePtr());
789
790  case Type::Elaborated:
791    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
792
793  case Type::TemplateSpecialization:
794    assert(getCanonicalType(T) != T &&
795           "Cannot request the size of a dependent type");
796    // FIXME: this is likely to be wrong once we support template
797    // aliases, since a template alias could refer to a typedef that
798    // has an __aligned__ attribute on it.
799    return getTypeInfo(getCanonicalType(T));
800  }
801
802  assert(Align && (Align & (Align-1)) == 0 && "Alignment must be power of 2");
803  return std::make_pair(Width, Align);
804}
805
806/// getTypeSizeInChars - Return the size of the specified type, in characters.
807/// This method does not work on incomplete types.
808CharUnits ASTContext::getTypeSizeInChars(QualType T) {
809  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
810}
811CharUnits ASTContext::getTypeSizeInChars(const Type *T) {
812  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
813}
814
815/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
816/// characters. This method does not work on incomplete types.
817CharUnits ASTContext::getTypeAlignInChars(QualType T) {
818  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
819}
820CharUnits ASTContext::getTypeAlignInChars(const Type *T) {
821  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
822}
823
824/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
825/// type for the current target in bits.  This can be different than the ABI
826/// alignment in cases where it is beneficial for performance to overalign
827/// a data type.
828unsigned ASTContext::getPreferredTypeAlign(const Type *T) {
829  unsigned ABIAlign = getTypeAlign(T);
830
831  // Double and long long should be naturally aligned if possible.
832  if (const ComplexType* CT = T->getAs<ComplexType>())
833    T = CT->getElementType().getTypePtr();
834  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
835      T->isSpecificBuiltinType(BuiltinType::LongLong))
836    return std::max(ABIAlign, (unsigned)getTypeSize(T));
837
838  return ABIAlign;
839}
840
841static void CollectLocalObjCIvars(ASTContext *Ctx,
842                                  const ObjCInterfaceDecl *OI,
843                                  llvm::SmallVectorImpl<FieldDecl*> &Fields) {
844  for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
845       E = OI->ivar_end(); I != E; ++I) {
846    ObjCIvarDecl *IVDecl = *I;
847    if (!IVDecl->isInvalidDecl())
848      Fields.push_back(cast<FieldDecl>(IVDecl));
849  }
850}
851
852void ASTContext::CollectObjCIvars(const ObjCInterfaceDecl *OI,
853                             llvm::SmallVectorImpl<FieldDecl*> &Fields) {
854  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
855    CollectObjCIvars(SuperClass, Fields);
856  CollectLocalObjCIvars(this, OI, Fields);
857}
858
859/// ShallowCollectObjCIvars -
860/// Collect all ivars, including those synthesized, in the current class.
861///
862void ASTContext::ShallowCollectObjCIvars(const ObjCInterfaceDecl *OI,
863                                 llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
864  for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
865         E = OI->ivar_end(); I != E; ++I) {
866     Ivars.push_back(*I);
867  }
868
869  CollectNonClassIvars(OI, Ivars);
870}
871
872/// CollectNonClassIvars -
873/// This routine collects all other ivars which are not declared in the class.
874/// This includes synthesized ivars (via @synthesize) and those in
875//  class's @implementation.
876///
877void ASTContext::CollectNonClassIvars(const ObjCInterfaceDecl *OI,
878                                llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
879  // Find ivars declared in class extension.
880  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
881       CDecl = CDecl->getNextClassExtension()) {
882    for (ObjCCategoryDecl::ivar_iterator I = CDecl->ivar_begin(),
883         E = CDecl->ivar_end(); I != E; ++I) {
884      Ivars.push_back(*I);
885    }
886  }
887
888  // Also add any ivar defined in this class's implementation.  This
889  // includes synthesized ivars.
890  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation()) {
891    for (ObjCImplementationDecl::ivar_iterator I = ImplDecl->ivar_begin(),
892         E = ImplDecl->ivar_end(); I != E; ++I)
893      Ivars.push_back(*I);
894  }
895}
896
897/// CollectInheritedProtocols - Collect all protocols in current class and
898/// those inherited by it.
899void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
900                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
901  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
902    for (ObjCInterfaceDecl::protocol_iterator P = OI->protocol_begin(),
903         PE = OI->protocol_end(); P != PE; ++P) {
904      ObjCProtocolDecl *Proto = (*P);
905      Protocols.insert(Proto);
906      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
907           PE = Proto->protocol_end(); P != PE; ++P) {
908        Protocols.insert(*P);
909        CollectInheritedProtocols(*P, Protocols);
910      }
911    }
912
913    // Categories of this Interface.
914    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
915         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
916      CollectInheritedProtocols(CDeclChain, Protocols);
917    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
918      while (SD) {
919        CollectInheritedProtocols(SD, Protocols);
920        SD = SD->getSuperClass();
921      }
922  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
923    for (ObjCInterfaceDecl::protocol_iterator P = OC->protocol_begin(),
924         PE = OC->protocol_end(); P != PE; ++P) {
925      ObjCProtocolDecl *Proto = (*P);
926      Protocols.insert(Proto);
927      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
928           PE = Proto->protocol_end(); P != PE; ++P)
929        CollectInheritedProtocols(*P, Protocols);
930    }
931  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
932    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
933         PE = OP->protocol_end(); P != PE; ++P) {
934      ObjCProtocolDecl *Proto = (*P);
935      Protocols.insert(Proto);
936      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
937           PE = Proto->protocol_end(); P != PE; ++P)
938        CollectInheritedProtocols(*P, Protocols);
939    }
940  }
941}
942
943unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) {
944  unsigned count = 0;
945  // Count ivars declared in class extension.
946  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
947       CDecl = CDecl->getNextClassExtension())
948    count += CDecl->ivar_size();
949
950  // Count ivar defined in this class's implementation.  This
951  // includes synthesized ivars.
952  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
953    count += ImplDecl->ivar_size();
954
955  return count;
956}
957
958/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
959ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
960  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
961    I = ObjCImpls.find(D);
962  if (I != ObjCImpls.end())
963    return cast<ObjCImplementationDecl>(I->second);
964  return 0;
965}
966/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
967ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
968  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
969    I = ObjCImpls.find(D);
970  if (I != ObjCImpls.end())
971    return cast<ObjCCategoryImplDecl>(I->second);
972  return 0;
973}
974
975/// \brief Set the implementation of ObjCInterfaceDecl.
976void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
977                           ObjCImplementationDecl *ImplD) {
978  assert(IFaceD && ImplD && "Passed null params");
979  ObjCImpls[IFaceD] = ImplD;
980}
981/// \brief Set the implementation of ObjCCategoryDecl.
982void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
983                           ObjCCategoryImplDecl *ImplD) {
984  assert(CatD && ImplD && "Passed null params");
985  ObjCImpls[CatD] = ImplD;
986}
987
988/// \brief Allocate an uninitialized TypeSourceInfo.
989///
990/// The caller should initialize the memory held by TypeSourceInfo using
991/// the TypeLoc wrappers.
992///
993/// \param T the type that will be the basis for type source info. This type
994/// should refer to how the declarator was written in source code, not to
995/// what type semantic analysis resolved the declarator to.
996TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
997                                                 unsigned DataSize) {
998  if (!DataSize)
999    DataSize = TypeLoc::getFullDataSizeForType(T);
1000  else
1001    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1002           "incorrect data size provided to CreateTypeSourceInfo!");
1003
1004  TypeSourceInfo *TInfo =
1005    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1006  new (TInfo) TypeSourceInfo(T);
1007  return TInfo;
1008}
1009
1010TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1011                                                     SourceLocation L) {
1012  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1013  DI->getTypeLoc().initialize(L);
1014  return DI;
1015}
1016
1017const ASTRecordLayout &
1018ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) {
1019  return getObjCLayout(D, 0);
1020}
1021
1022const ASTRecordLayout &
1023ASTContext::getASTObjCImplementationLayout(const ObjCImplementationDecl *D) {
1024  return getObjCLayout(D->getClassInterface(), D);
1025}
1026
1027//===----------------------------------------------------------------------===//
1028//                   Type creation/memoization methods
1029//===----------------------------------------------------------------------===//
1030
1031QualType ASTContext::getExtQualType(const Type *TypeNode, Qualifiers Quals) {
1032  unsigned Fast = Quals.getFastQualifiers();
1033  Quals.removeFastQualifiers();
1034
1035  // Check if we've already instantiated this type.
1036  llvm::FoldingSetNodeID ID;
1037  ExtQuals::Profile(ID, TypeNode, Quals);
1038  void *InsertPos = 0;
1039  if (ExtQuals *EQ = ExtQualNodes.FindNodeOrInsertPos(ID, InsertPos)) {
1040    assert(EQ->getQualifiers() == Quals);
1041    QualType T = QualType(EQ, Fast);
1042    return T;
1043  }
1044
1045  ExtQuals *New = new (*this, TypeAlignment) ExtQuals(*this, TypeNode, Quals);
1046  ExtQualNodes.InsertNode(New, InsertPos);
1047  QualType T = QualType(New, Fast);
1048  return T;
1049}
1050
1051QualType ASTContext::getVolatileType(QualType T) {
1052  QualType CanT = getCanonicalType(T);
1053  if (CanT.isVolatileQualified()) return T;
1054
1055  QualifierCollector Quals;
1056  const Type *TypeNode = Quals.strip(T);
1057  Quals.addVolatile();
1058
1059  return getExtQualType(TypeNode, Quals);
1060}
1061
1062QualType ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) {
1063  QualType CanT = getCanonicalType(T);
1064  if (CanT.getAddressSpace() == AddressSpace)
1065    return T;
1066
1067  // If we are composing extended qualifiers together, merge together
1068  // into one ExtQuals node.
1069  QualifierCollector Quals;
1070  const Type *TypeNode = Quals.strip(T);
1071
1072  // If this type already has an address space specified, it cannot get
1073  // another one.
1074  assert(!Quals.hasAddressSpace() &&
1075         "Type cannot be in multiple addr spaces!");
1076  Quals.addAddressSpace(AddressSpace);
1077
1078  return getExtQualType(TypeNode, Quals);
1079}
1080
1081QualType ASTContext::getObjCGCQualType(QualType T,
1082                                       Qualifiers::GC GCAttr) {
1083  QualType CanT = getCanonicalType(T);
1084  if (CanT.getObjCGCAttr() == GCAttr)
1085    return T;
1086
1087  if (T->isPointerType()) {
1088    QualType Pointee = T->getAs<PointerType>()->getPointeeType();
1089    if (Pointee->isAnyPointerType()) {
1090      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1091      return getPointerType(ResultType);
1092    }
1093  }
1094
1095  // If we are composing extended qualifiers together, merge together
1096  // into one ExtQuals node.
1097  QualifierCollector Quals;
1098  const Type *TypeNode = Quals.strip(T);
1099
1100  // If this type already has an ObjCGC specified, it cannot get
1101  // another one.
1102  assert(!Quals.hasObjCGCAttr() &&
1103         "Type cannot have multiple ObjCGCs!");
1104  Quals.addObjCGCAttr(GCAttr);
1105
1106  return getExtQualType(TypeNode, Quals);
1107}
1108
1109static QualType getExtFunctionType(ASTContext& Context, QualType T,
1110                                        const FunctionType::ExtInfo &Info) {
1111  QualType ResultType;
1112  if (const PointerType *Pointer = T->getAs<PointerType>()) {
1113    QualType Pointee = Pointer->getPointeeType();
1114    ResultType = getExtFunctionType(Context, Pointee, Info);
1115    if (ResultType == Pointee)
1116      return T;
1117
1118    ResultType = Context.getPointerType(ResultType);
1119  } else if (const BlockPointerType *BlockPointer
1120                                              = T->getAs<BlockPointerType>()) {
1121    QualType Pointee = BlockPointer->getPointeeType();
1122    ResultType = getExtFunctionType(Context, Pointee, Info);
1123    if (ResultType == Pointee)
1124      return T;
1125
1126    ResultType = Context.getBlockPointerType(ResultType);
1127   } else if (const FunctionType *F = T->getAs<FunctionType>()) {
1128    if (F->getExtInfo() == Info)
1129      return T;
1130
1131    if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(F)) {
1132      ResultType = Context.getFunctionNoProtoType(FNPT->getResultType(),
1133                                                  Info);
1134    } else {
1135      const FunctionProtoType *FPT = cast<FunctionProtoType>(F);
1136      ResultType
1137        = Context.getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1138                                  FPT->getNumArgs(), FPT->isVariadic(),
1139                                  FPT->getTypeQuals(),
1140                                  FPT->hasExceptionSpec(),
1141                                  FPT->hasAnyExceptionSpec(),
1142                                  FPT->getNumExceptions(),
1143                                  FPT->exception_begin(),
1144                                  Info);
1145    }
1146  } else
1147    return T;
1148
1149  return Context.getQualifiedType(ResultType, T.getLocalQualifiers());
1150}
1151
1152QualType ASTContext::getNoReturnType(QualType T, bool AddNoReturn) {
1153  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1154  return getExtFunctionType(*this, T,
1155                                 Info.withNoReturn(AddNoReturn));
1156}
1157
1158QualType ASTContext::getCallConvType(QualType T, CallingConv CallConv) {
1159  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1160  return getExtFunctionType(*this, T,
1161                            Info.withCallingConv(CallConv));
1162}
1163
1164QualType ASTContext::getRegParmType(QualType T, unsigned RegParm) {
1165  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1166  return getExtFunctionType(*this, T,
1167                                 Info.withRegParm(RegParm));
1168}
1169
1170/// getComplexType - Return the uniqued reference to the type for a complex
1171/// number with the specified element type.
1172QualType ASTContext::getComplexType(QualType T) {
1173  // Unique pointers, to guarantee there is only one pointer of a particular
1174  // structure.
1175  llvm::FoldingSetNodeID ID;
1176  ComplexType::Profile(ID, T);
1177
1178  void *InsertPos = 0;
1179  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1180    return QualType(CT, 0);
1181
1182  // If the pointee type isn't canonical, this won't be a canonical type either,
1183  // so fill in the canonical type field.
1184  QualType Canonical;
1185  if (!T.isCanonical()) {
1186    Canonical = getComplexType(getCanonicalType(T));
1187
1188    // Get the new insert position for the node we care about.
1189    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1190    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1191  }
1192  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1193  Types.push_back(New);
1194  ComplexTypes.InsertNode(New, InsertPos);
1195  return QualType(New, 0);
1196}
1197
1198/// getPointerType - Return the uniqued reference to the type for a pointer to
1199/// the specified type.
1200QualType ASTContext::getPointerType(QualType T) {
1201  // Unique pointers, to guarantee there is only one pointer of a particular
1202  // structure.
1203  llvm::FoldingSetNodeID ID;
1204  PointerType::Profile(ID, T);
1205
1206  void *InsertPos = 0;
1207  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1208    return QualType(PT, 0);
1209
1210  // If the pointee type isn't canonical, this won't be a canonical type either,
1211  // so fill in the canonical type field.
1212  QualType Canonical;
1213  if (!T.isCanonical()) {
1214    Canonical = getPointerType(getCanonicalType(T));
1215
1216    // Get the new insert position for the node we care about.
1217    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1218    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1219  }
1220  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1221  Types.push_back(New);
1222  PointerTypes.InsertNode(New, InsertPos);
1223  return QualType(New, 0);
1224}
1225
1226/// getBlockPointerType - Return the uniqued reference to the type for
1227/// a pointer to the specified block.
1228QualType ASTContext::getBlockPointerType(QualType T) {
1229  assert(T->isFunctionType() && "block of function types only");
1230  // Unique pointers, to guarantee there is only one block of a particular
1231  // structure.
1232  llvm::FoldingSetNodeID ID;
1233  BlockPointerType::Profile(ID, T);
1234
1235  void *InsertPos = 0;
1236  if (BlockPointerType *PT =
1237        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1238    return QualType(PT, 0);
1239
1240  // If the block pointee type isn't canonical, this won't be a canonical
1241  // type either so fill in the canonical type field.
1242  QualType Canonical;
1243  if (!T.isCanonical()) {
1244    Canonical = getBlockPointerType(getCanonicalType(T));
1245
1246    // Get the new insert position for the node we care about.
1247    BlockPointerType *NewIP =
1248      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1249    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1250  }
1251  BlockPointerType *New
1252    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1253  Types.push_back(New);
1254  BlockPointerTypes.InsertNode(New, InsertPos);
1255  return QualType(New, 0);
1256}
1257
1258/// getLValueReferenceType - Return the uniqued reference to the type for an
1259/// lvalue reference to the specified type.
1260QualType ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) {
1261  // Unique pointers, to guarantee there is only one pointer of a particular
1262  // structure.
1263  llvm::FoldingSetNodeID ID;
1264  ReferenceType::Profile(ID, T, SpelledAsLValue);
1265
1266  void *InsertPos = 0;
1267  if (LValueReferenceType *RT =
1268        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1269    return QualType(RT, 0);
1270
1271  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1272
1273  // If the referencee type isn't canonical, this won't be a canonical type
1274  // either, so fill in the canonical type field.
1275  QualType Canonical;
1276  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1277    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1278    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1279
1280    // Get the new insert position for the node we care about.
1281    LValueReferenceType *NewIP =
1282      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1283    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1284  }
1285
1286  LValueReferenceType *New
1287    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1288                                                     SpelledAsLValue);
1289  Types.push_back(New);
1290  LValueReferenceTypes.InsertNode(New, InsertPos);
1291
1292  return QualType(New, 0);
1293}
1294
1295/// getRValueReferenceType - Return the uniqued reference to the type for an
1296/// rvalue reference to the specified type.
1297QualType ASTContext::getRValueReferenceType(QualType T) {
1298  // Unique pointers, to guarantee there is only one pointer of a particular
1299  // structure.
1300  llvm::FoldingSetNodeID ID;
1301  ReferenceType::Profile(ID, T, false);
1302
1303  void *InsertPos = 0;
1304  if (RValueReferenceType *RT =
1305        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1306    return QualType(RT, 0);
1307
1308  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1309
1310  // If the referencee type isn't canonical, this won't be a canonical type
1311  // either, so fill in the canonical type field.
1312  QualType Canonical;
1313  if (InnerRef || !T.isCanonical()) {
1314    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1315    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1316
1317    // Get the new insert position for the node we care about.
1318    RValueReferenceType *NewIP =
1319      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1320    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1321  }
1322
1323  RValueReferenceType *New
1324    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1325  Types.push_back(New);
1326  RValueReferenceTypes.InsertNode(New, InsertPos);
1327  return QualType(New, 0);
1328}
1329
1330/// getMemberPointerType - Return the uniqued reference to the type for a
1331/// member pointer to the specified type, in the specified class.
1332QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) {
1333  // Unique pointers, to guarantee there is only one pointer of a particular
1334  // structure.
1335  llvm::FoldingSetNodeID ID;
1336  MemberPointerType::Profile(ID, T, Cls);
1337
1338  void *InsertPos = 0;
1339  if (MemberPointerType *PT =
1340      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1341    return QualType(PT, 0);
1342
1343  // If the pointee or class type isn't canonical, this won't be a canonical
1344  // type either, so fill in the canonical type field.
1345  QualType Canonical;
1346  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1347    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1348
1349    // Get the new insert position for the node we care about.
1350    MemberPointerType *NewIP =
1351      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1352    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1353  }
1354  MemberPointerType *New
1355    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1356  Types.push_back(New);
1357  MemberPointerTypes.InsertNode(New, InsertPos);
1358  return QualType(New, 0);
1359}
1360
1361/// getConstantArrayType - Return the unique reference to the type for an
1362/// array of the specified element type.
1363QualType ASTContext::getConstantArrayType(QualType EltTy,
1364                                          const llvm::APInt &ArySizeIn,
1365                                          ArrayType::ArraySizeModifier ASM,
1366                                          unsigned EltTypeQuals) {
1367  assert((EltTy->isDependentType() ||
1368          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1369         "Constant array of VLAs is illegal!");
1370
1371  // Convert the array size into a canonical width matching the pointer size for
1372  // the target.
1373  llvm::APInt ArySize(ArySizeIn);
1374  ArySize.zextOrTrunc(Target.getPointerWidth(EltTy.getAddressSpace()));
1375
1376  llvm::FoldingSetNodeID ID;
1377  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, EltTypeQuals);
1378
1379  void *InsertPos = 0;
1380  if (ConstantArrayType *ATP =
1381      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1382    return QualType(ATP, 0);
1383
1384  // If the element type isn't canonical, this won't be a canonical type either,
1385  // so fill in the canonical type field.
1386  QualType Canonical;
1387  if (!EltTy.isCanonical()) {
1388    Canonical = getConstantArrayType(getCanonicalType(EltTy), ArySize,
1389                                     ASM, EltTypeQuals);
1390    // Get the new insert position for the node we care about.
1391    ConstantArrayType *NewIP =
1392      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1393    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1394  }
1395
1396  ConstantArrayType *New = new(*this,TypeAlignment)
1397    ConstantArrayType(EltTy, Canonical, ArySize, ASM, EltTypeQuals);
1398  ConstantArrayTypes.InsertNode(New, InsertPos);
1399  Types.push_back(New);
1400  return QualType(New, 0);
1401}
1402
1403/// getVariableArrayType - Returns a non-unique reference to the type for a
1404/// variable array of the specified element type.
1405QualType ASTContext::getVariableArrayType(QualType EltTy,
1406                                          Expr *NumElts,
1407                                          ArrayType::ArraySizeModifier ASM,
1408                                          unsigned EltTypeQuals,
1409                                          SourceRange Brackets) {
1410  // Since we don't unique expressions, it isn't possible to unique VLA's
1411  // that have an expression provided for their size.
1412  QualType CanonType;
1413
1414  if (!EltTy.isCanonical()) {
1415    if (NumElts)
1416      NumElts->Retain();
1417    CanonType = getVariableArrayType(getCanonicalType(EltTy), NumElts, ASM,
1418                                     EltTypeQuals, Brackets);
1419  }
1420
1421  VariableArrayType *New = new(*this, TypeAlignment)
1422    VariableArrayType(EltTy, CanonType, NumElts, ASM, EltTypeQuals, Brackets);
1423
1424  VariableArrayTypes.push_back(New);
1425  Types.push_back(New);
1426  return QualType(New, 0);
1427}
1428
1429/// getDependentSizedArrayType - Returns a non-unique reference to
1430/// the type for a dependently-sized array of the specified element
1431/// type.
1432QualType ASTContext::getDependentSizedArrayType(QualType EltTy,
1433                                                Expr *NumElts,
1434                                                ArrayType::ArraySizeModifier ASM,
1435                                                unsigned EltTypeQuals,
1436                                                SourceRange Brackets) {
1437  assert((!NumElts || NumElts->isTypeDependent() ||
1438          NumElts->isValueDependent()) &&
1439         "Size must be type- or value-dependent!");
1440
1441  void *InsertPos = 0;
1442  DependentSizedArrayType *Canon = 0;
1443  llvm::FoldingSetNodeID ID;
1444
1445  if (NumElts) {
1446    // Dependently-sized array types that do not have a specified
1447    // number of elements will have their sizes deduced from an
1448    // initializer.
1449    DependentSizedArrayType::Profile(ID, *this, getCanonicalType(EltTy), ASM,
1450                                     EltTypeQuals, NumElts);
1451
1452    Canon = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1453  }
1454
1455  DependentSizedArrayType *New;
1456  if (Canon) {
1457    // We already have a canonical version of this array type; use it as
1458    // the canonical type for a newly-built type.
1459    New = new (*this, TypeAlignment)
1460      DependentSizedArrayType(*this, EltTy, QualType(Canon, 0),
1461                              NumElts, ASM, EltTypeQuals, Brackets);
1462  } else {
1463    QualType CanonEltTy = getCanonicalType(EltTy);
1464    if (CanonEltTy == EltTy) {
1465      New = new (*this, TypeAlignment)
1466        DependentSizedArrayType(*this, EltTy, QualType(),
1467                                NumElts, ASM, EltTypeQuals, Brackets);
1468
1469      if (NumElts) {
1470        DependentSizedArrayType *CanonCheck
1471          = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1472        assert(!CanonCheck && "Dependent-sized canonical array type broken");
1473        (void)CanonCheck;
1474        DependentSizedArrayTypes.InsertNode(New, InsertPos);
1475      }
1476    } else {
1477      QualType Canon = getDependentSizedArrayType(CanonEltTy, NumElts,
1478                                                  ASM, EltTypeQuals,
1479                                                  SourceRange());
1480      New = new (*this, TypeAlignment)
1481        DependentSizedArrayType(*this, EltTy, Canon,
1482                                NumElts, ASM, EltTypeQuals, Brackets);
1483    }
1484  }
1485
1486  Types.push_back(New);
1487  return QualType(New, 0);
1488}
1489
1490QualType ASTContext::getIncompleteArrayType(QualType EltTy,
1491                                            ArrayType::ArraySizeModifier ASM,
1492                                            unsigned EltTypeQuals) {
1493  llvm::FoldingSetNodeID ID;
1494  IncompleteArrayType::Profile(ID, EltTy, ASM, EltTypeQuals);
1495
1496  void *InsertPos = 0;
1497  if (IncompleteArrayType *ATP =
1498       IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1499    return QualType(ATP, 0);
1500
1501  // If the element type isn't canonical, this won't be a canonical type
1502  // either, so fill in the canonical type field.
1503  QualType Canonical;
1504
1505  if (!EltTy.isCanonical()) {
1506    Canonical = getIncompleteArrayType(getCanonicalType(EltTy),
1507                                       ASM, EltTypeQuals);
1508
1509    // Get the new insert position for the node we care about.
1510    IncompleteArrayType *NewIP =
1511      IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1512    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1513  }
1514
1515  IncompleteArrayType *New = new (*this, TypeAlignment)
1516    IncompleteArrayType(EltTy, Canonical, ASM, EltTypeQuals);
1517
1518  IncompleteArrayTypes.InsertNode(New, InsertPos);
1519  Types.push_back(New);
1520  return QualType(New, 0);
1521}
1522
1523/// getVectorType - Return the unique reference to a vector type of
1524/// the specified element type and size. VectorType must be a built-in type.
1525QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1526    VectorType::AltiVecSpecific AltiVecSpec) {
1527  BuiltinType *baseType;
1528
1529  baseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1530  assert(baseType != 0 && "getVectorType(): Expecting a built-in type");
1531
1532  // Check if we've already instantiated a vector of this type.
1533  llvm::FoldingSetNodeID ID;
1534  VectorType::Profile(ID, vecType, NumElts, Type::Vector, AltiVecSpec);
1535
1536  void *InsertPos = 0;
1537  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1538    return QualType(VTP, 0);
1539
1540  // If the element type isn't canonical, this won't be a canonical type either,
1541  // so fill in the canonical type field.
1542  QualType Canonical;
1543  if (!vecType.isCanonical()) {
1544    Canonical = getVectorType(getCanonicalType(vecType), NumElts,
1545      VectorType::NotAltiVec);
1546
1547    // Get the new insert position for the node we care about.
1548    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1549    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1550  }
1551  VectorType *New = new (*this, TypeAlignment)
1552    VectorType(vecType, NumElts, Canonical, AltiVecSpec);
1553  VectorTypes.InsertNode(New, InsertPos);
1554  Types.push_back(New);
1555  return QualType(New, 0);
1556}
1557
1558/// getExtVectorType - Return the unique reference to an extended vector type of
1559/// the specified element type and size. VectorType must be a built-in type.
1560QualType ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) {
1561  BuiltinType *baseType;
1562
1563  baseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1564  assert(baseType != 0 && "getExtVectorType(): Expecting a built-in type");
1565
1566  // Check if we've already instantiated a vector of this type.
1567  llvm::FoldingSetNodeID ID;
1568  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1569                      VectorType::NotAltiVec);
1570  void *InsertPos = 0;
1571  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1572    return QualType(VTP, 0);
1573
1574  // If the element type isn't canonical, this won't be a canonical type either,
1575  // so fill in the canonical type field.
1576  QualType Canonical;
1577  if (!vecType.isCanonical()) {
1578    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
1579
1580    // Get the new insert position for the node we care about.
1581    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1582    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1583  }
1584  ExtVectorType *New = new (*this, TypeAlignment)
1585    ExtVectorType(vecType, NumElts, Canonical);
1586  VectorTypes.InsertNode(New, InsertPos);
1587  Types.push_back(New);
1588  return QualType(New, 0);
1589}
1590
1591QualType ASTContext::getDependentSizedExtVectorType(QualType vecType,
1592                                                    Expr *SizeExpr,
1593                                                    SourceLocation AttrLoc) {
1594  llvm::FoldingSetNodeID ID;
1595  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
1596                                       SizeExpr);
1597
1598  void *InsertPos = 0;
1599  DependentSizedExtVectorType *Canon
1600    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1601  DependentSizedExtVectorType *New;
1602  if (Canon) {
1603    // We already have a canonical version of this array type; use it as
1604    // the canonical type for a newly-built type.
1605    New = new (*this, TypeAlignment)
1606      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
1607                                  SizeExpr, AttrLoc);
1608  } else {
1609    QualType CanonVecTy = getCanonicalType(vecType);
1610    if (CanonVecTy == vecType) {
1611      New = new (*this, TypeAlignment)
1612        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
1613                                    AttrLoc);
1614
1615      DependentSizedExtVectorType *CanonCheck
1616        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1617      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
1618      (void)CanonCheck;
1619      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
1620    } else {
1621      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
1622                                                      SourceLocation());
1623      New = new (*this, TypeAlignment)
1624        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
1625    }
1626  }
1627
1628  Types.push_back(New);
1629  return QualType(New, 0);
1630}
1631
1632/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
1633///
1634QualType ASTContext::getFunctionNoProtoType(QualType ResultTy,
1635                                            const FunctionType::ExtInfo &Info) {
1636  const CallingConv CallConv = Info.getCC();
1637  // Unique functions, to guarantee there is only one function of a particular
1638  // structure.
1639  llvm::FoldingSetNodeID ID;
1640  FunctionNoProtoType::Profile(ID, ResultTy, Info);
1641
1642  void *InsertPos = 0;
1643  if (FunctionNoProtoType *FT =
1644        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1645    return QualType(FT, 0);
1646
1647  QualType Canonical;
1648  if (!ResultTy.isCanonical() ||
1649      getCanonicalCallConv(CallConv) != CallConv) {
1650    Canonical =
1651      getFunctionNoProtoType(getCanonicalType(ResultTy),
1652                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1653
1654    // Get the new insert position for the node we care about.
1655    FunctionNoProtoType *NewIP =
1656      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1657    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1658  }
1659
1660  FunctionNoProtoType *New = new (*this, TypeAlignment)
1661    FunctionNoProtoType(ResultTy, Canonical, Info);
1662  Types.push_back(New);
1663  FunctionNoProtoTypes.InsertNode(New, InsertPos);
1664  return QualType(New, 0);
1665}
1666
1667/// getFunctionType - Return a normal function type with a typed argument
1668/// list.  isVariadic indicates whether the argument list includes '...'.
1669QualType ASTContext::getFunctionType(QualType ResultTy,const QualType *ArgArray,
1670                                     unsigned NumArgs, bool isVariadic,
1671                                     unsigned TypeQuals, bool hasExceptionSpec,
1672                                     bool hasAnyExceptionSpec, unsigned NumExs,
1673                                     const QualType *ExArray,
1674                                     const FunctionType::ExtInfo &Info) {
1675  const CallingConv CallConv= Info.getCC();
1676  // Unique functions, to guarantee there is only one function of a particular
1677  // structure.
1678  llvm::FoldingSetNodeID ID;
1679  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, isVariadic,
1680                             TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1681                             NumExs, ExArray, Info);
1682
1683  void *InsertPos = 0;
1684  if (FunctionProtoType *FTP =
1685        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1686    return QualType(FTP, 0);
1687
1688  // Determine whether the type being created is already canonical or not.
1689  bool isCanonical = !hasExceptionSpec && ResultTy.isCanonical();
1690  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
1691    if (!ArgArray[i].isCanonicalAsParam())
1692      isCanonical = false;
1693
1694  // If this type isn't canonical, get the canonical version of it.
1695  // The exception spec is not part of the canonical type.
1696  QualType Canonical;
1697  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
1698    llvm::SmallVector<QualType, 16> CanonicalArgs;
1699    CanonicalArgs.reserve(NumArgs);
1700    for (unsigned i = 0; i != NumArgs; ++i)
1701      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
1702
1703    Canonical = getFunctionType(getCanonicalType(ResultTy),
1704                                CanonicalArgs.data(), NumArgs,
1705                                isVariadic, TypeQuals, false,
1706                                false, 0, 0,
1707                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1708
1709    // Get the new insert position for the node we care about.
1710    FunctionProtoType *NewIP =
1711      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1712    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1713  }
1714
1715  // FunctionProtoType objects are allocated with extra bytes after them
1716  // for two variable size arrays (for parameter and exception types) at the
1717  // end of them.
1718  FunctionProtoType *FTP =
1719    (FunctionProtoType*)Allocate(sizeof(FunctionProtoType) +
1720                                 NumArgs*sizeof(QualType) +
1721                                 NumExs*sizeof(QualType), TypeAlignment);
1722  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, isVariadic,
1723                              TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1724                              ExArray, NumExs, Canonical, Info);
1725  Types.push_back(FTP);
1726  FunctionProtoTypes.InsertNode(FTP, InsertPos);
1727  return QualType(FTP, 0);
1728}
1729
1730#ifndef NDEBUG
1731static bool NeedsInjectedClassNameType(const RecordDecl *D) {
1732  if (!isa<CXXRecordDecl>(D)) return false;
1733  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
1734  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
1735    return true;
1736  if (RD->getDescribedClassTemplate() &&
1737      !isa<ClassTemplateSpecializationDecl>(RD))
1738    return true;
1739  return false;
1740}
1741#endif
1742
1743/// getInjectedClassNameType - Return the unique reference to the
1744/// injected class name type for the specified templated declaration.
1745QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
1746                                              QualType TST) {
1747  assert(NeedsInjectedClassNameType(Decl));
1748  if (Decl->TypeForDecl) {
1749    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1750  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDeclaration()) {
1751    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
1752    Decl->TypeForDecl = PrevDecl->TypeForDecl;
1753    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1754  } else {
1755    Decl->TypeForDecl =
1756      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
1757    Types.push_back(Decl->TypeForDecl);
1758  }
1759  return QualType(Decl->TypeForDecl, 0);
1760}
1761
1762/// getTypeDeclType - Return the unique reference to the type for the
1763/// specified type declaration.
1764QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) {
1765  assert(Decl && "Passed null for Decl param");
1766  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
1767
1768  if (const TypedefDecl *Typedef = dyn_cast<TypedefDecl>(Decl))
1769    return getTypedefType(Typedef);
1770
1771  assert(!isa<TemplateTypeParmDecl>(Decl) &&
1772         "Template type parameter types are always available.");
1773
1774  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
1775    assert(!Record->getPreviousDeclaration() &&
1776           "struct/union has previous declaration");
1777    assert(!NeedsInjectedClassNameType(Record));
1778    return getRecordType(Record);
1779  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
1780    assert(!Enum->getPreviousDeclaration() &&
1781           "enum has previous declaration");
1782    return getEnumType(Enum);
1783  } else if (const UnresolvedUsingTypenameDecl *Using =
1784               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
1785    Decl->TypeForDecl = new (*this, TypeAlignment) UnresolvedUsingType(Using);
1786  } else
1787    llvm_unreachable("TypeDecl without a type?");
1788
1789  Types.push_back(Decl->TypeForDecl);
1790  return QualType(Decl->TypeForDecl, 0);
1791}
1792
1793/// getTypedefType - Return the unique reference to the type for the
1794/// specified typename decl.
1795QualType
1796ASTContext::getTypedefType(const TypedefDecl *Decl, QualType Canonical) {
1797  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1798
1799  if (Canonical.isNull())
1800    Canonical = getCanonicalType(Decl->getUnderlyingType());
1801  Decl->TypeForDecl = new(*this, TypeAlignment)
1802    TypedefType(Type::Typedef, Decl, Canonical);
1803  Types.push_back(Decl->TypeForDecl);
1804  return QualType(Decl->TypeForDecl, 0);
1805}
1806
1807QualType ASTContext::getRecordType(const RecordDecl *Decl) {
1808  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1809
1810  if (const RecordDecl *PrevDecl = Decl->getPreviousDeclaration())
1811    if (PrevDecl->TypeForDecl)
1812      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1813
1814  Decl->TypeForDecl = new (*this, TypeAlignment) RecordType(Decl);
1815  Types.push_back(Decl->TypeForDecl);
1816  return QualType(Decl->TypeForDecl, 0);
1817}
1818
1819QualType ASTContext::getEnumType(const EnumDecl *Decl) {
1820  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1821
1822  if (const EnumDecl *PrevDecl = Decl->getPreviousDeclaration())
1823    if (PrevDecl->TypeForDecl)
1824      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1825
1826  Decl->TypeForDecl = new (*this, TypeAlignment) EnumType(Decl);
1827  Types.push_back(Decl->TypeForDecl);
1828  return QualType(Decl->TypeForDecl, 0);
1829}
1830
1831/// \brief Retrieve a substitution-result type.
1832QualType
1833ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
1834                                         QualType Replacement) {
1835  assert(Replacement.isCanonical()
1836         && "replacement types must always be canonical");
1837
1838  llvm::FoldingSetNodeID ID;
1839  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
1840  void *InsertPos = 0;
1841  SubstTemplateTypeParmType *SubstParm
1842    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1843
1844  if (!SubstParm) {
1845    SubstParm = new (*this, TypeAlignment)
1846      SubstTemplateTypeParmType(Parm, Replacement);
1847    Types.push_back(SubstParm);
1848    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
1849  }
1850
1851  return QualType(SubstParm, 0);
1852}
1853
1854/// \brief Retrieve the template type parameter type for a template
1855/// parameter or parameter pack with the given depth, index, and (optionally)
1856/// name.
1857QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
1858                                             bool ParameterPack,
1859                                             IdentifierInfo *Name) {
1860  llvm::FoldingSetNodeID ID;
1861  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, Name);
1862  void *InsertPos = 0;
1863  TemplateTypeParmType *TypeParm
1864    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1865
1866  if (TypeParm)
1867    return QualType(TypeParm, 0);
1868
1869  if (Name) {
1870    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
1871    TypeParm = new (*this, TypeAlignment)
1872      TemplateTypeParmType(Depth, Index, ParameterPack, Name, Canon);
1873
1874    TemplateTypeParmType *TypeCheck
1875      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1876    assert(!TypeCheck && "Template type parameter canonical type broken");
1877    (void)TypeCheck;
1878  } else
1879    TypeParm = new (*this, TypeAlignment)
1880      TemplateTypeParmType(Depth, Index, ParameterPack);
1881
1882  Types.push_back(TypeParm);
1883  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
1884
1885  return QualType(TypeParm, 0);
1886}
1887
1888TypeSourceInfo *
1889ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
1890                                              SourceLocation NameLoc,
1891                                        const TemplateArgumentListInfo &Args,
1892                                              QualType CanonType) {
1893  QualType TST = getTemplateSpecializationType(Name, Args, CanonType);
1894
1895  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
1896  TemplateSpecializationTypeLoc TL
1897    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
1898  TL.setTemplateNameLoc(NameLoc);
1899  TL.setLAngleLoc(Args.getLAngleLoc());
1900  TL.setRAngleLoc(Args.getRAngleLoc());
1901  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
1902    TL.setArgLocInfo(i, Args[i].getLocInfo());
1903  return DI;
1904}
1905
1906QualType
1907ASTContext::getTemplateSpecializationType(TemplateName Template,
1908                                          const TemplateArgumentListInfo &Args,
1909                                          QualType Canon) {
1910  unsigned NumArgs = Args.size();
1911
1912  llvm::SmallVector<TemplateArgument, 4> ArgVec;
1913  ArgVec.reserve(NumArgs);
1914  for (unsigned i = 0; i != NumArgs; ++i)
1915    ArgVec.push_back(Args[i].getArgument());
1916
1917  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
1918                                       Canon);
1919}
1920
1921QualType
1922ASTContext::getTemplateSpecializationType(TemplateName Template,
1923                                          const TemplateArgument *Args,
1924                                          unsigned NumArgs,
1925                                          QualType Canon) {
1926  if (!Canon.isNull())
1927    Canon = getCanonicalType(Canon);
1928  else
1929    Canon = getCanonicalTemplateSpecializationType(Template, Args, NumArgs);
1930
1931  // Allocate the (non-canonical) template specialization type, but don't
1932  // try to unique it: these types typically have location information that
1933  // we don't unique and don't want to lose.
1934  void *Mem = Allocate((sizeof(TemplateSpecializationType) +
1935                        sizeof(TemplateArgument) * NumArgs),
1936                       TypeAlignment);
1937  TemplateSpecializationType *Spec
1938    = new (Mem) TemplateSpecializationType(Template,
1939                                           Args, NumArgs,
1940                                           Canon);
1941
1942  Types.push_back(Spec);
1943  return QualType(Spec, 0);
1944}
1945
1946QualType
1947ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
1948                                                   const TemplateArgument *Args,
1949                                                   unsigned NumArgs) {
1950  // Build the canonical template specialization type.
1951  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
1952  llvm::SmallVector<TemplateArgument, 4> CanonArgs;
1953  CanonArgs.reserve(NumArgs);
1954  for (unsigned I = 0; I != NumArgs; ++I)
1955    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
1956
1957  // Determine whether this canonical template specialization type already
1958  // exists.
1959  llvm::FoldingSetNodeID ID;
1960  TemplateSpecializationType::Profile(ID, CanonTemplate,
1961                                      CanonArgs.data(), NumArgs, *this);
1962
1963  void *InsertPos = 0;
1964  TemplateSpecializationType *Spec
1965    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
1966
1967  if (!Spec) {
1968    // Allocate a new canonical template specialization type.
1969    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
1970                          sizeof(TemplateArgument) * NumArgs),
1971                         TypeAlignment);
1972    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
1973                                                CanonArgs.data(), NumArgs,
1974                                                QualType());
1975    Types.push_back(Spec);
1976    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
1977  }
1978
1979  assert(Spec->isDependentType() &&
1980         "Non-dependent template-id type must have a canonical type");
1981  return QualType(Spec, 0);
1982}
1983
1984QualType
1985ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
1986                              NestedNameSpecifier *NNS,
1987                              QualType NamedType) {
1988  llvm::FoldingSetNodeID ID;
1989  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
1990
1991  void *InsertPos = 0;
1992  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
1993  if (T)
1994    return QualType(T, 0);
1995
1996  QualType Canon = NamedType;
1997  if (!Canon.isCanonical()) {
1998    Canon = getCanonicalType(NamedType);
1999    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2000    assert(!CheckT && "Elaborated canonical type broken");
2001    (void)CheckT;
2002  }
2003
2004  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2005  Types.push_back(T);
2006  ElaboratedTypes.InsertNode(T, InsertPos);
2007  return QualType(T, 0);
2008}
2009
2010QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2011                                          NestedNameSpecifier *NNS,
2012                                          const IdentifierInfo *Name,
2013                                          QualType Canon) {
2014  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2015
2016  if (Canon.isNull()) {
2017    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2018    ElaboratedTypeKeyword CanonKeyword = Keyword;
2019    if (Keyword == ETK_None)
2020      CanonKeyword = ETK_Typename;
2021
2022    if (CanonNNS != NNS || CanonKeyword != Keyword)
2023      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2024  }
2025
2026  llvm::FoldingSetNodeID ID;
2027  DependentNameType::Profile(ID, Keyword, NNS, Name);
2028
2029  void *InsertPos = 0;
2030  DependentNameType *T
2031    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2032  if (T)
2033    return QualType(T, 0);
2034
2035  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2036  Types.push_back(T);
2037  DependentNameTypes.InsertNode(T, InsertPos);
2038  return QualType(T, 0);
2039}
2040
2041QualType
2042ASTContext::getDependentTemplateSpecializationType(
2043                                 ElaboratedTypeKeyword Keyword,
2044                                 NestedNameSpecifier *NNS,
2045                                 const IdentifierInfo *Name,
2046                                 const TemplateArgumentListInfo &Args) {
2047  // TODO: avoid this copy
2048  llvm::SmallVector<TemplateArgument, 16> ArgCopy;
2049  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2050    ArgCopy.push_back(Args[I].getArgument());
2051  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2052                                                ArgCopy.size(),
2053                                                ArgCopy.data());
2054}
2055
2056QualType
2057ASTContext::getDependentTemplateSpecializationType(
2058                                 ElaboratedTypeKeyword Keyword,
2059                                 NestedNameSpecifier *NNS,
2060                                 const IdentifierInfo *Name,
2061                                 unsigned NumArgs,
2062                                 const TemplateArgument *Args) {
2063  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2064
2065  llvm::FoldingSetNodeID ID;
2066  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2067                                               Name, NumArgs, Args);
2068
2069  void *InsertPos = 0;
2070  DependentTemplateSpecializationType *T
2071    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2072  if (T)
2073    return QualType(T, 0);
2074
2075  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2076
2077  ElaboratedTypeKeyword CanonKeyword = Keyword;
2078  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2079
2080  bool AnyNonCanonArgs = false;
2081  llvm::SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2082  for (unsigned I = 0; I != NumArgs; ++I) {
2083    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2084    if (!CanonArgs[I].structurallyEquals(Args[I]))
2085      AnyNonCanonArgs = true;
2086  }
2087
2088  QualType Canon;
2089  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2090    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2091                                                   Name, NumArgs,
2092                                                   CanonArgs.data());
2093
2094    // Find the insert position again.
2095    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2096  }
2097
2098  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2099                        sizeof(TemplateArgument) * NumArgs),
2100                       TypeAlignment);
2101  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2102                                                    Name, NumArgs, Args, Canon);
2103  Types.push_back(T);
2104  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2105  return QualType(T, 0);
2106}
2107
2108/// CmpProtocolNames - Comparison predicate for sorting protocols
2109/// alphabetically.
2110static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2111                            const ObjCProtocolDecl *RHS) {
2112  return LHS->getDeclName() < RHS->getDeclName();
2113}
2114
2115static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2116                                unsigned NumProtocols) {
2117  if (NumProtocols == 0) return true;
2118
2119  for (unsigned i = 1; i != NumProtocols; ++i)
2120    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]))
2121      return false;
2122  return true;
2123}
2124
2125static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2126                                   unsigned &NumProtocols) {
2127  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2128
2129  // Sort protocols, keyed by name.
2130  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2131
2132  // Remove duplicates.
2133  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2134  NumProtocols = ProtocolsEnd-Protocols;
2135}
2136
2137QualType ASTContext::getObjCObjectType(QualType BaseType,
2138                                       ObjCProtocolDecl * const *Protocols,
2139                                       unsigned NumProtocols) {
2140  // If the base type is an interface and there aren't any protocols
2141  // to add, then the interface type will do just fine.
2142  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2143    return BaseType;
2144
2145  // Look in the folding set for an existing type.
2146  llvm::FoldingSetNodeID ID;
2147  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2148  void *InsertPos = 0;
2149  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2150    return QualType(QT, 0);
2151
2152  // Build the canonical type, which has the canonical base type and
2153  // a sorted-and-uniqued list of protocols.
2154  QualType Canonical;
2155  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2156  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2157    if (!ProtocolsSorted) {
2158      llvm::SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2159                                                     Protocols + NumProtocols);
2160      unsigned UniqueCount = NumProtocols;
2161
2162      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2163      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2164                                    &Sorted[0], UniqueCount);
2165    } else {
2166      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2167                                    Protocols, NumProtocols);
2168    }
2169
2170    // Regenerate InsertPos.
2171    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2172  }
2173
2174  unsigned Size = sizeof(ObjCObjectTypeImpl);
2175  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2176  void *Mem = Allocate(Size, TypeAlignment);
2177  ObjCObjectTypeImpl *T =
2178    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2179
2180  Types.push_back(T);
2181  ObjCObjectTypes.InsertNode(T, InsertPos);
2182  return QualType(T, 0);
2183}
2184
2185/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2186/// the given object type.
2187QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) {
2188  llvm::FoldingSetNodeID ID;
2189  ObjCObjectPointerType::Profile(ID, ObjectT);
2190
2191  void *InsertPos = 0;
2192  if (ObjCObjectPointerType *QT =
2193              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2194    return QualType(QT, 0);
2195
2196  // Find the canonical object type.
2197  QualType Canonical;
2198  if (!ObjectT.isCanonical()) {
2199    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2200
2201    // Regenerate InsertPos.
2202    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2203  }
2204
2205  // No match.
2206  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2207  ObjCObjectPointerType *QType =
2208    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2209
2210  Types.push_back(QType);
2211  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2212  return QualType(QType, 0);
2213}
2214
2215/// getObjCInterfaceType - Return the unique reference to the type for the
2216/// specified ObjC interface decl. The list of protocols is optional.
2217QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl) {
2218  if (Decl->TypeForDecl)
2219    return QualType(Decl->TypeForDecl, 0);
2220
2221  // FIXME: redeclarations?
2222  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2223  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2224  Decl->TypeForDecl = T;
2225  Types.push_back(T);
2226  return QualType(T, 0);
2227}
2228
2229/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2230/// TypeOfExprType AST's (since expression's are never shared). For example,
2231/// multiple declarations that refer to "typeof(x)" all contain different
2232/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2233/// on canonical type's (which are always unique).
2234QualType ASTContext::getTypeOfExprType(Expr *tofExpr) {
2235  TypeOfExprType *toe;
2236  if (tofExpr->isTypeDependent()) {
2237    llvm::FoldingSetNodeID ID;
2238    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2239
2240    void *InsertPos = 0;
2241    DependentTypeOfExprType *Canon
2242      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2243    if (Canon) {
2244      // We already have a "canonical" version of an identical, dependent
2245      // typeof(expr) type. Use that as our canonical type.
2246      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2247                                          QualType((TypeOfExprType*)Canon, 0));
2248    }
2249    else {
2250      // Build a new, canonical typeof(expr) type.
2251      Canon
2252        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2253      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2254      toe = Canon;
2255    }
2256  } else {
2257    QualType Canonical = getCanonicalType(tofExpr->getType());
2258    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2259  }
2260  Types.push_back(toe);
2261  return QualType(toe, 0);
2262}
2263
2264/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2265/// TypeOfType AST's. The only motivation to unique these nodes would be
2266/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2267/// an issue. This doesn't effect the type checker, since it operates
2268/// on canonical type's (which are always unique).
2269QualType ASTContext::getTypeOfType(QualType tofType) {
2270  QualType Canonical = getCanonicalType(tofType);
2271  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2272  Types.push_back(tot);
2273  return QualType(tot, 0);
2274}
2275
2276/// getDecltypeForExpr - Given an expr, will return the decltype for that
2277/// expression, according to the rules in C++0x [dcl.type.simple]p4
2278static QualType getDecltypeForExpr(const Expr *e, ASTContext &Context) {
2279  if (e->isTypeDependent())
2280    return Context.DependentTy;
2281
2282  // If e is an id expression or a class member access, decltype(e) is defined
2283  // as the type of the entity named by e.
2284  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2285    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2286      return VD->getType();
2287  }
2288  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2289    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2290      return FD->getType();
2291  }
2292  // If e is a function call or an invocation of an overloaded operator,
2293  // (parentheses around e are ignored), decltype(e) is defined as the
2294  // return type of that function.
2295  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2296    return CE->getCallReturnType();
2297
2298  QualType T = e->getType();
2299
2300  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2301  // defined as T&, otherwise decltype(e) is defined as T.
2302  if (e->isLvalue(Context) == Expr::LV_Valid)
2303    T = Context.getLValueReferenceType(T);
2304
2305  return T;
2306}
2307
2308/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2309/// DecltypeType AST's. The only motivation to unique these nodes would be
2310/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2311/// an issue. This doesn't effect the type checker, since it operates
2312/// on canonical type's (which are always unique).
2313QualType ASTContext::getDecltypeType(Expr *e) {
2314  DecltypeType *dt;
2315  if (e->isTypeDependent()) {
2316    llvm::FoldingSetNodeID ID;
2317    DependentDecltypeType::Profile(ID, *this, e);
2318
2319    void *InsertPos = 0;
2320    DependentDecltypeType *Canon
2321      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2322    if (Canon) {
2323      // We already have a "canonical" version of an equivalent, dependent
2324      // decltype type. Use that as our canonical type.
2325      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2326                                       QualType((DecltypeType*)Canon, 0));
2327    }
2328    else {
2329      // Build a new, canonical typeof(expr) type.
2330      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2331      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2332      dt = Canon;
2333    }
2334  } else {
2335    QualType T = getDecltypeForExpr(e, *this);
2336    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2337  }
2338  Types.push_back(dt);
2339  return QualType(dt, 0);
2340}
2341
2342/// getTagDeclType - Return the unique reference to the type for the
2343/// specified TagDecl (struct/union/class/enum) decl.
2344QualType ASTContext::getTagDeclType(const TagDecl *Decl) {
2345  assert (Decl);
2346  // FIXME: What is the design on getTagDeclType when it requires casting
2347  // away const?  mutable?
2348  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2349}
2350
2351/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2352/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2353/// needs to agree with the definition in <stddef.h>.
2354CanQualType ASTContext::getSizeType() const {
2355  return getFromTargetType(Target.getSizeType());
2356}
2357
2358/// getSignedWCharType - Return the type of "signed wchar_t".
2359/// Used when in C++, as a GCC extension.
2360QualType ASTContext::getSignedWCharType() const {
2361  // FIXME: derive from "Target" ?
2362  return WCharTy;
2363}
2364
2365/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
2366/// Used when in C++, as a GCC extension.
2367QualType ASTContext::getUnsignedWCharType() const {
2368  // FIXME: derive from "Target" ?
2369  return UnsignedIntTy;
2370}
2371
2372/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
2373/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
2374QualType ASTContext::getPointerDiffType() const {
2375  return getFromTargetType(Target.getPtrDiffType(0));
2376}
2377
2378//===----------------------------------------------------------------------===//
2379//                              Type Operators
2380//===----------------------------------------------------------------------===//
2381
2382CanQualType ASTContext::getCanonicalParamType(QualType T) {
2383  // Push qualifiers into arrays, and then discard any remaining
2384  // qualifiers.
2385  T = getCanonicalType(T);
2386  const Type *Ty = T.getTypePtr();
2387
2388  QualType Result;
2389  if (isa<ArrayType>(Ty)) {
2390    Result = getArrayDecayedType(QualType(Ty,0));
2391  } else if (isa<FunctionType>(Ty)) {
2392    Result = getPointerType(QualType(Ty, 0));
2393  } else {
2394    Result = QualType(Ty, 0);
2395  }
2396
2397  return CanQualType::CreateUnsafe(Result);
2398}
2399
2400/// getCanonicalType - Return the canonical (structural) type corresponding to
2401/// the specified potentially non-canonical type.  The non-canonical version
2402/// of a type may have many "decorated" versions of types.  Decorators can
2403/// include typedefs, 'typeof' operators, etc. The returned type is guaranteed
2404/// to be free of any of these, allowing two canonical types to be compared
2405/// for exact equality with a simple pointer comparison.
2406CanQualType ASTContext::getCanonicalType(QualType T) {
2407  QualifierCollector Quals;
2408  const Type *Ptr = Quals.strip(T);
2409  QualType CanType = Ptr->getCanonicalTypeInternal();
2410
2411  // The canonical internal type will be the canonical type *except*
2412  // that we push type qualifiers down through array types.
2413
2414  // If there are no new qualifiers to push down, stop here.
2415  if (!Quals.hasQualifiers())
2416    return CanQualType::CreateUnsafe(CanType);
2417
2418  // If the type qualifiers are on an array type, get the canonical
2419  // type of the array with the qualifiers applied to the element
2420  // type.
2421  ArrayType *AT = dyn_cast<ArrayType>(CanType);
2422  if (!AT)
2423    return CanQualType::CreateUnsafe(getQualifiedType(CanType, Quals));
2424
2425  // Get the canonical version of the element with the extra qualifiers on it.
2426  // This can recursively sink qualifiers through multiple levels of arrays.
2427  QualType NewEltTy = getQualifiedType(AT->getElementType(), Quals);
2428  NewEltTy = getCanonicalType(NewEltTy);
2429
2430  if (ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
2431    return CanQualType::CreateUnsafe(
2432             getConstantArrayType(NewEltTy, CAT->getSize(),
2433                                  CAT->getSizeModifier(),
2434                                  CAT->getIndexTypeCVRQualifiers()));
2435  if (IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT))
2436    return CanQualType::CreateUnsafe(
2437             getIncompleteArrayType(NewEltTy, IAT->getSizeModifier(),
2438                                    IAT->getIndexTypeCVRQualifiers()));
2439
2440  if (DependentSizedArrayType *DSAT = dyn_cast<DependentSizedArrayType>(AT))
2441    return CanQualType::CreateUnsafe(
2442             getDependentSizedArrayType(NewEltTy,
2443                                        DSAT->getSizeExpr() ?
2444                                          DSAT->getSizeExpr()->Retain() : 0,
2445                                        DSAT->getSizeModifier(),
2446                                        DSAT->getIndexTypeCVRQualifiers(),
2447                        DSAT->getBracketsRange())->getCanonicalTypeInternal());
2448
2449  VariableArrayType *VAT = cast<VariableArrayType>(AT);
2450  return CanQualType::CreateUnsafe(getVariableArrayType(NewEltTy,
2451                                                        VAT->getSizeExpr() ?
2452                                              VAT->getSizeExpr()->Retain() : 0,
2453                                                        VAT->getSizeModifier(),
2454                                              VAT->getIndexTypeCVRQualifiers(),
2455                                                     VAT->getBracketsRange()));
2456}
2457
2458QualType ASTContext::getUnqualifiedArrayType(QualType T,
2459                                             Qualifiers &Quals) {
2460  Quals = T.getQualifiers();
2461  const ArrayType *AT = getAsArrayType(T);
2462  if (!AT) {
2463    return T.getUnqualifiedType();
2464  }
2465
2466  QualType Elt = AT->getElementType();
2467  QualType UnqualElt = getUnqualifiedArrayType(Elt, Quals);
2468  if (Elt == UnqualElt)
2469    return T;
2470
2471  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
2472    return getConstantArrayType(UnqualElt, CAT->getSize(),
2473                                CAT->getSizeModifier(), 0);
2474  }
2475
2476  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
2477    return getIncompleteArrayType(UnqualElt, IAT->getSizeModifier(), 0);
2478  }
2479
2480  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
2481    return getVariableArrayType(UnqualElt,
2482                                VAT->getSizeExpr() ?
2483                                VAT->getSizeExpr()->Retain() : 0,
2484                                VAT->getSizeModifier(),
2485                                VAT->getIndexTypeCVRQualifiers(),
2486                                VAT->getBracketsRange());
2487  }
2488
2489  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
2490  return getDependentSizedArrayType(UnqualElt, DSAT->getSizeExpr()->Retain(),
2491                                    DSAT->getSizeModifier(), 0,
2492                                    SourceRange());
2493}
2494
2495/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
2496/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
2497/// they point to and return true. If T1 and T2 aren't pointer types
2498/// or pointer-to-member types, or if they are not similar at this
2499/// level, returns false and leaves T1 and T2 unchanged. Top-level
2500/// qualifiers on T1 and T2 are ignored. This function will typically
2501/// be called in a loop that successively "unwraps" pointer and
2502/// pointer-to-member types to compare them at each level.
2503bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
2504  const PointerType *T1PtrType = T1->getAs<PointerType>(),
2505                    *T2PtrType = T2->getAs<PointerType>();
2506  if (T1PtrType && T2PtrType) {
2507    T1 = T1PtrType->getPointeeType();
2508    T2 = T2PtrType->getPointeeType();
2509    return true;
2510  }
2511
2512  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
2513                          *T2MPType = T2->getAs<MemberPointerType>();
2514  if (T1MPType && T2MPType &&
2515      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
2516                             QualType(T2MPType->getClass(), 0))) {
2517    T1 = T1MPType->getPointeeType();
2518    T2 = T2MPType->getPointeeType();
2519    return true;
2520  }
2521
2522  if (getLangOptions().ObjC1) {
2523    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
2524                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
2525    if (T1OPType && T2OPType) {
2526      T1 = T1OPType->getPointeeType();
2527      T2 = T2OPType->getPointeeType();
2528      return true;
2529    }
2530  }
2531
2532  // FIXME: Block pointers, too?
2533
2534  return false;
2535}
2536
2537DeclarationNameInfo ASTContext::getNameForTemplate(TemplateName Name,
2538                                                   SourceLocation NameLoc) {
2539  if (TemplateDecl *TD = Name.getAsTemplateDecl())
2540    // DNInfo work in progress: CHECKME: what about DNLoc?
2541    return DeclarationNameInfo(TD->getDeclName(), NameLoc);
2542
2543  if (DependentTemplateName *DTN = Name.getAsDependentTemplateName()) {
2544    DeclarationName DName;
2545    if (DTN->isIdentifier()) {
2546      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
2547      return DeclarationNameInfo(DName, NameLoc);
2548    } else {
2549      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
2550      // DNInfo work in progress: FIXME: source locations?
2551      DeclarationNameLoc DNLoc;
2552      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
2553      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
2554      return DeclarationNameInfo(DName, NameLoc, DNLoc);
2555    }
2556  }
2557
2558  OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
2559  assert(Storage);
2560  // DNInfo work in progress: CHECKME: what about DNLoc?
2561  return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
2562}
2563
2564TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) {
2565  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
2566    if (TemplateTemplateParmDecl *TTP
2567                              = dyn_cast<TemplateTemplateParmDecl>(Template))
2568      Template = getCanonicalTemplateTemplateParmDecl(TTP);
2569
2570    // The canonical template name is the canonical template declaration.
2571    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
2572  }
2573
2574  assert(!Name.getAsOverloadedTemplate());
2575
2576  DependentTemplateName *DTN = Name.getAsDependentTemplateName();
2577  assert(DTN && "Non-dependent template names must refer to template decls.");
2578  return DTN->CanonicalTemplateName;
2579}
2580
2581bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
2582  X = getCanonicalTemplateName(X);
2583  Y = getCanonicalTemplateName(Y);
2584  return X.getAsVoidPointer() == Y.getAsVoidPointer();
2585}
2586
2587TemplateArgument
2588ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) {
2589  switch (Arg.getKind()) {
2590    case TemplateArgument::Null:
2591      return Arg;
2592
2593    case TemplateArgument::Expression:
2594      return Arg;
2595
2596    case TemplateArgument::Declaration:
2597      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
2598
2599    case TemplateArgument::Template:
2600      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
2601
2602    case TemplateArgument::Integral:
2603      return TemplateArgument(*Arg.getAsIntegral(),
2604                              getCanonicalType(Arg.getIntegralType()));
2605
2606    case TemplateArgument::Type:
2607      return TemplateArgument(getCanonicalType(Arg.getAsType()));
2608
2609    case TemplateArgument::Pack: {
2610      // FIXME: Allocate in ASTContext
2611      TemplateArgument *CanonArgs = new TemplateArgument[Arg.pack_size()];
2612      unsigned Idx = 0;
2613      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
2614                                        AEnd = Arg.pack_end();
2615           A != AEnd; (void)++A, ++Idx)
2616        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
2617
2618      TemplateArgument Result;
2619      Result.setArgumentPack(CanonArgs, Arg.pack_size(), false);
2620      return Result;
2621    }
2622  }
2623
2624  // Silence GCC warning
2625  assert(false && "Unhandled template argument kind");
2626  return TemplateArgument();
2627}
2628
2629NestedNameSpecifier *
2630ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) {
2631  if (!NNS)
2632    return 0;
2633
2634  switch (NNS->getKind()) {
2635  case NestedNameSpecifier::Identifier:
2636    // Canonicalize the prefix but keep the identifier the same.
2637    return NestedNameSpecifier::Create(*this,
2638                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
2639                                       NNS->getAsIdentifier());
2640
2641  case NestedNameSpecifier::Namespace:
2642    // A namespace is canonical; build a nested-name-specifier with
2643    // this namespace and no prefix.
2644    return NestedNameSpecifier::Create(*this, 0, NNS->getAsNamespace());
2645
2646  case NestedNameSpecifier::TypeSpec:
2647  case NestedNameSpecifier::TypeSpecWithTemplate: {
2648    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
2649    return NestedNameSpecifier::Create(*this, 0,
2650                 NNS->getKind() == NestedNameSpecifier::TypeSpecWithTemplate,
2651                                       T.getTypePtr());
2652  }
2653
2654  case NestedNameSpecifier::Global:
2655    // The global specifier is canonical and unique.
2656    return NNS;
2657  }
2658
2659  // Required to silence a GCC warning
2660  return 0;
2661}
2662
2663
2664const ArrayType *ASTContext::getAsArrayType(QualType T) {
2665  // Handle the non-qualified case efficiently.
2666  if (!T.hasLocalQualifiers()) {
2667    // Handle the common positive case fast.
2668    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
2669      return AT;
2670  }
2671
2672  // Handle the common negative case fast.
2673  QualType CType = T->getCanonicalTypeInternal();
2674  if (!isa<ArrayType>(CType))
2675    return 0;
2676
2677  // Apply any qualifiers from the array type to the element type.  This
2678  // implements C99 6.7.3p8: "If the specification of an array type includes
2679  // any type qualifiers, the element type is so qualified, not the array type."
2680
2681  // If we get here, we either have type qualifiers on the type, or we have
2682  // sugar such as a typedef in the way.  If we have type qualifiers on the type
2683  // we must propagate them down into the element type.
2684
2685  QualifierCollector Qs;
2686  const Type *Ty = Qs.strip(T.getDesugaredType());
2687
2688  // If we have a simple case, just return now.
2689  const ArrayType *ATy = dyn_cast<ArrayType>(Ty);
2690  if (ATy == 0 || Qs.empty())
2691    return ATy;
2692
2693  // Otherwise, we have an array and we have qualifiers on it.  Push the
2694  // qualifiers into the array element type and return a new array type.
2695  // Get the canonical version of the element with the extra qualifiers on it.
2696  // This can recursively sink qualifiers through multiple levels of arrays.
2697  QualType NewEltTy = getQualifiedType(ATy->getElementType(), Qs);
2698
2699  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
2700    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
2701                                                CAT->getSizeModifier(),
2702                                           CAT->getIndexTypeCVRQualifiers()));
2703  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
2704    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
2705                                                  IAT->getSizeModifier(),
2706                                           IAT->getIndexTypeCVRQualifiers()));
2707
2708  if (const DependentSizedArrayType *DSAT
2709        = dyn_cast<DependentSizedArrayType>(ATy))
2710    return cast<ArrayType>(
2711                     getDependentSizedArrayType(NewEltTy,
2712                                                DSAT->getSizeExpr() ?
2713                                              DSAT->getSizeExpr()->Retain() : 0,
2714                                                DSAT->getSizeModifier(),
2715                                              DSAT->getIndexTypeCVRQualifiers(),
2716                                                DSAT->getBracketsRange()));
2717
2718  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
2719  return cast<ArrayType>(getVariableArrayType(NewEltTy,
2720                                              VAT->getSizeExpr() ?
2721                                              VAT->getSizeExpr()->Retain() : 0,
2722                                              VAT->getSizeModifier(),
2723                                              VAT->getIndexTypeCVRQualifiers(),
2724                                              VAT->getBracketsRange()));
2725}
2726
2727
2728/// getArrayDecayedType - Return the properly qualified result of decaying the
2729/// specified array type to a pointer.  This operation is non-trivial when
2730/// handling typedefs etc.  The canonical type of "T" must be an array type,
2731/// this returns a pointer to a properly qualified element of the array.
2732///
2733/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
2734QualType ASTContext::getArrayDecayedType(QualType Ty) {
2735  // Get the element type with 'getAsArrayType' so that we don't lose any
2736  // typedefs in the element type of the array.  This also handles propagation
2737  // of type qualifiers from the array type into the element type if present
2738  // (C99 6.7.3p8).
2739  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
2740  assert(PrettyArrayType && "Not an array type!");
2741
2742  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
2743
2744  // int x[restrict 4] ->  int *restrict
2745  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
2746}
2747
2748QualType ASTContext::getBaseElementType(QualType QT) {
2749  QualifierCollector Qs;
2750  while (const ArrayType *AT = getAsArrayType(QualType(Qs.strip(QT), 0)))
2751    QT = AT->getElementType();
2752  return Qs.apply(QT);
2753}
2754
2755QualType ASTContext::getBaseElementType(const ArrayType *AT) {
2756  QualType ElemTy = AT->getElementType();
2757
2758  if (const ArrayType *AT = getAsArrayType(ElemTy))
2759    return getBaseElementType(AT);
2760
2761  return ElemTy;
2762}
2763
2764/// getConstantArrayElementCount - Returns number of constant array elements.
2765uint64_t
2766ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
2767  uint64_t ElementCount = 1;
2768  do {
2769    ElementCount *= CA->getSize().getZExtValue();
2770    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
2771  } while (CA);
2772  return ElementCount;
2773}
2774
2775/// getFloatingRank - Return a relative rank for floating point types.
2776/// This routine will assert if passed a built-in type that isn't a float.
2777static FloatingRank getFloatingRank(QualType T) {
2778  if (const ComplexType *CT = T->getAs<ComplexType>())
2779    return getFloatingRank(CT->getElementType());
2780
2781  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
2782  switch (T->getAs<BuiltinType>()->getKind()) {
2783  default: assert(0 && "getFloatingRank(): not a floating type");
2784  case BuiltinType::Float:      return FloatRank;
2785  case BuiltinType::Double:     return DoubleRank;
2786  case BuiltinType::LongDouble: return LongDoubleRank;
2787  }
2788}
2789
2790/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
2791/// point or a complex type (based on typeDomain/typeSize).
2792/// 'typeDomain' is a real floating point or complex type.
2793/// 'typeSize' is a real floating point or complex type.
2794QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
2795                                                       QualType Domain) const {
2796  FloatingRank EltRank = getFloatingRank(Size);
2797  if (Domain->isComplexType()) {
2798    switch (EltRank) {
2799    default: assert(0 && "getFloatingRank(): illegal value for rank");
2800    case FloatRank:      return FloatComplexTy;
2801    case DoubleRank:     return DoubleComplexTy;
2802    case LongDoubleRank: return LongDoubleComplexTy;
2803    }
2804  }
2805
2806  assert(Domain->isRealFloatingType() && "Unknown domain!");
2807  switch (EltRank) {
2808  default: assert(0 && "getFloatingRank(): illegal value for rank");
2809  case FloatRank:      return FloatTy;
2810  case DoubleRank:     return DoubleTy;
2811  case LongDoubleRank: return LongDoubleTy;
2812  }
2813}
2814
2815/// getFloatingTypeOrder - Compare the rank of the two specified floating
2816/// point types, ignoring the domain of the type (i.e. 'double' ==
2817/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2818/// LHS < RHS, return -1.
2819int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) {
2820  FloatingRank LHSR = getFloatingRank(LHS);
2821  FloatingRank RHSR = getFloatingRank(RHS);
2822
2823  if (LHSR == RHSR)
2824    return 0;
2825  if (LHSR > RHSR)
2826    return 1;
2827  return -1;
2828}
2829
2830/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
2831/// routine will assert if passed a built-in type that isn't an integer or enum,
2832/// or if it is not canonicalized.
2833unsigned ASTContext::getIntegerRank(Type *T) {
2834  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
2835  if (EnumType* ET = dyn_cast<EnumType>(T))
2836    T = ET->getDecl()->getPromotionType().getTypePtr();
2837
2838  if (T->isSpecificBuiltinType(BuiltinType::WChar))
2839    T = getFromTargetType(Target.getWCharType()).getTypePtr();
2840
2841  if (T->isSpecificBuiltinType(BuiltinType::Char16))
2842    T = getFromTargetType(Target.getChar16Type()).getTypePtr();
2843
2844  if (T->isSpecificBuiltinType(BuiltinType::Char32))
2845    T = getFromTargetType(Target.getChar32Type()).getTypePtr();
2846
2847  switch (cast<BuiltinType>(T)->getKind()) {
2848  default: assert(0 && "getIntegerRank(): not a built-in integer");
2849  case BuiltinType::Bool:
2850    return 1 + (getIntWidth(BoolTy) << 3);
2851  case BuiltinType::Char_S:
2852  case BuiltinType::Char_U:
2853  case BuiltinType::SChar:
2854  case BuiltinType::UChar:
2855    return 2 + (getIntWidth(CharTy) << 3);
2856  case BuiltinType::Short:
2857  case BuiltinType::UShort:
2858    return 3 + (getIntWidth(ShortTy) << 3);
2859  case BuiltinType::Int:
2860  case BuiltinType::UInt:
2861    return 4 + (getIntWidth(IntTy) << 3);
2862  case BuiltinType::Long:
2863  case BuiltinType::ULong:
2864    return 5 + (getIntWidth(LongTy) << 3);
2865  case BuiltinType::LongLong:
2866  case BuiltinType::ULongLong:
2867    return 6 + (getIntWidth(LongLongTy) << 3);
2868  case BuiltinType::Int128:
2869  case BuiltinType::UInt128:
2870    return 7 + (getIntWidth(Int128Ty) << 3);
2871  }
2872}
2873
2874/// \brief Whether this is a promotable bitfield reference according
2875/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
2876///
2877/// \returns the type this bit-field will promote to, or NULL if no
2878/// promotion occurs.
2879QualType ASTContext::isPromotableBitField(Expr *E) {
2880  if (E->isTypeDependent() || E->isValueDependent())
2881    return QualType();
2882
2883  FieldDecl *Field = E->getBitField();
2884  if (!Field)
2885    return QualType();
2886
2887  QualType FT = Field->getType();
2888
2889  llvm::APSInt BitWidthAP = Field->getBitWidth()->EvaluateAsInt(*this);
2890  uint64_t BitWidth = BitWidthAP.getZExtValue();
2891  uint64_t IntSize = getTypeSize(IntTy);
2892  // GCC extension compatibility: if the bit-field size is less than or equal
2893  // to the size of int, it gets promoted no matter what its type is.
2894  // For instance, unsigned long bf : 4 gets promoted to signed int.
2895  if (BitWidth < IntSize)
2896    return IntTy;
2897
2898  if (BitWidth == IntSize)
2899    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
2900
2901  // Types bigger than int are not subject to promotions, and therefore act
2902  // like the base type.
2903  // FIXME: This doesn't quite match what gcc does, but what gcc does here
2904  // is ridiculous.
2905  return QualType();
2906}
2907
2908/// getPromotedIntegerType - Returns the type that Promotable will
2909/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
2910/// integer type.
2911QualType ASTContext::getPromotedIntegerType(QualType Promotable) {
2912  assert(!Promotable.isNull());
2913  assert(Promotable->isPromotableIntegerType());
2914  if (const EnumType *ET = Promotable->getAs<EnumType>())
2915    return ET->getDecl()->getPromotionType();
2916  if (Promotable->isSignedIntegerType())
2917    return IntTy;
2918  uint64_t PromotableSize = getTypeSize(Promotable);
2919  uint64_t IntSize = getTypeSize(IntTy);
2920  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
2921  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
2922}
2923
2924/// getIntegerTypeOrder - Returns the highest ranked integer type:
2925/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2926/// LHS < RHS, return -1.
2927int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) {
2928  Type *LHSC = getCanonicalType(LHS).getTypePtr();
2929  Type *RHSC = getCanonicalType(RHS).getTypePtr();
2930  if (LHSC == RHSC) return 0;
2931
2932  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
2933  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
2934
2935  unsigned LHSRank = getIntegerRank(LHSC);
2936  unsigned RHSRank = getIntegerRank(RHSC);
2937
2938  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
2939    if (LHSRank == RHSRank) return 0;
2940    return LHSRank > RHSRank ? 1 : -1;
2941  }
2942
2943  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
2944  if (LHSUnsigned) {
2945    // If the unsigned [LHS] type is larger, return it.
2946    if (LHSRank >= RHSRank)
2947      return 1;
2948
2949    // If the signed type can represent all values of the unsigned type, it
2950    // wins.  Because we are dealing with 2's complement and types that are
2951    // powers of two larger than each other, this is always safe.
2952    return -1;
2953  }
2954
2955  // If the unsigned [RHS] type is larger, return it.
2956  if (RHSRank >= LHSRank)
2957    return -1;
2958
2959  // If the signed type can represent all values of the unsigned type, it
2960  // wins.  Because we are dealing with 2's complement and types that are
2961  // powers of two larger than each other, this is always safe.
2962  return 1;
2963}
2964
2965static RecordDecl *
2966CreateRecordDecl(ASTContext &Ctx, RecordDecl::TagKind TK, DeclContext *DC,
2967                 SourceLocation L, IdentifierInfo *Id) {
2968  if (Ctx.getLangOptions().CPlusPlus)
2969    return CXXRecordDecl::Create(Ctx, TK, DC, L, Id);
2970  else
2971    return RecordDecl::Create(Ctx, TK, DC, L, Id);
2972}
2973
2974// getCFConstantStringType - Return the type used for constant CFStrings.
2975QualType ASTContext::getCFConstantStringType() {
2976  if (!CFConstantStringTypeDecl) {
2977    CFConstantStringTypeDecl =
2978      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
2979                       &Idents.get("NSConstantString"));
2980    CFConstantStringTypeDecl->startDefinition();
2981
2982    QualType FieldTypes[4];
2983
2984    // const int *isa;
2985    FieldTypes[0] = getPointerType(IntTy.withConst());
2986    // int flags;
2987    FieldTypes[1] = IntTy;
2988    // const char *str;
2989    FieldTypes[2] = getPointerType(CharTy.withConst());
2990    // long length;
2991    FieldTypes[3] = LongTy;
2992
2993    // Create fields
2994    for (unsigned i = 0; i < 4; ++i) {
2995      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
2996                                           SourceLocation(), 0,
2997                                           FieldTypes[i], /*TInfo=*/0,
2998                                           /*BitWidth=*/0,
2999                                           /*Mutable=*/false);
3000      Field->setAccess(AS_public);
3001      CFConstantStringTypeDecl->addDecl(Field);
3002    }
3003
3004    CFConstantStringTypeDecl->completeDefinition();
3005  }
3006
3007  return getTagDeclType(CFConstantStringTypeDecl);
3008}
3009
3010void ASTContext::setCFConstantStringType(QualType T) {
3011  const RecordType *Rec = T->getAs<RecordType>();
3012  assert(Rec && "Invalid CFConstantStringType");
3013  CFConstantStringTypeDecl = Rec->getDecl();
3014}
3015
3016// getNSConstantStringType - Return the type used for constant NSStrings.
3017QualType ASTContext::getNSConstantStringType() {
3018  if (!NSConstantStringTypeDecl) {
3019    NSConstantStringTypeDecl =
3020    CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3021                     &Idents.get("__builtin_NSString"));
3022    NSConstantStringTypeDecl->startDefinition();
3023
3024    QualType FieldTypes[3];
3025
3026    // const int *isa;
3027    FieldTypes[0] = getPointerType(IntTy.withConst());
3028    // const char *str;
3029    FieldTypes[1] = getPointerType(CharTy.withConst());
3030    // unsigned int length;
3031    FieldTypes[2] = UnsignedIntTy;
3032
3033    // Create fields
3034    for (unsigned i = 0; i < 3; ++i) {
3035      FieldDecl *Field = FieldDecl::Create(*this, NSConstantStringTypeDecl,
3036                                           SourceLocation(), 0,
3037                                           FieldTypes[i], /*TInfo=*/0,
3038                                           /*BitWidth=*/0,
3039                                           /*Mutable=*/false);
3040      Field->setAccess(AS_public);
3041      NSConstantStringTypeDecl->addDecl(Field);
3042    }
3043
3044    NSConstantStringTypeDecl->completeDefinition();
3045  }
3046
3047  return getTagDeclType(NSConstantStringTypeDecl);
3048}
3049
3050void ASTContext::setNSConstantStringType(QualType T) {
3051  const RecordType *Rec = T->getAs<RecordType>();
3052  assert(Rec && "Invalid NSConstantStringType");
3053  NSConstantStringTypeDecl = Rec->getDecl();
3054}
3055
3056QualType ASTContext::getObjCFastEnumerationStateType() {
3057  if (!ObjCFastEnumerationStateTypeDecl) {
3058    ObjCFastEnumerationStateTypeDecl =
3059      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3060                       &Idents.get("__objcFastEnumerationState"));
3061    ObjCFastEnumerationStateTypeDecl->startDefinition();
3062
3063    QualType FieldTypes[] = {
3064      UnsignedLongTy,
3065      getPointerType(ObjCIdTypedefType),
3066      getPointerType(UnsignedLongTy),
3067      getConstantArrayType(UnsignedLongTy,
3068                           llvm::APInt(32, 5), ArrayType::Normal, 0)
3069    };
3070
3071    for (size_t i = 0; i < 4; ++i) {
3072      FieldDecl *Field = FieldDecl::Create(*this,
3073                                           ObjCFastEnumerationStateTypeDecl,
3074                                           SourceLocation(), 0,
3075                                           FieldTypes[i], /*TInfo=*/0,
3076                                           /*BitWidth=*/0,
3077                                           /*Mutable=*/false);
3078      Field->setAccess(AS_public);
3079      ObjCFastEnumerationStateTypeDecl->addDecl(Field);
3080    }
3081    if (getLangOptions().CPlusPlus)
3082      if (CXXRecordDecl *CXXRD =
3083            dyn_cast<CXXRecordDecl>(ObjCFastEnumerationStateTypeDecl))
3084        CXXRD->setEmpty(false);
3085
3086    ObjCFastEnumerationStateTypeDecl->completeDefinition();
3087  }
3088
3089  return getTagDeclType(ObjCFastEnumerationStateTypeDecl);
3090}
3091
3092QualType ASTContext::getBlockDescriptorType() {
3093  if (BlockDescriptorType)
3094    return getTagDeclType(BlockDescriptorType);
3095
3096  RecordDecl *T;
3097  // FIXME: Needs the FlagAppleBlock bit.
3098  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3099                       &Idents.get("__block_descriptor"));
3100  T->startDefinition();
3101
3102  QualType FieldTypes[] = {
3103    UnsignedLongTy,
3104    UnsignedLongTy,
3105  };
3106
3107  const char *FieldNames[] = {
3108    "reserved",
3109    "Size"
3110  };
3111
3112  for (size_t i = 0; i < 2; ++i) {
3113    FieldDecl *Field = FieldDecl::Create(*this,
3114                                         T,
3115                                         SourceLocation(),
3116                                         &Idents.get(FieldNames[i]),
3117                                         FieldTypes[i], /*TInfo=*/0,
3118                                         /*BitWidth=*/0,
3119                                         /*Mutable=*/false);
3120    Field->setAccess(AS_public);
3121    T->addDecl(Field);
3122  }
3123
3124  T->completeDefinition();
3125
3126  BlockDescriptorType = T;
3127
3128  return getTagDeclType(BlockDescriptorType);
3129}
3130
3131void ASTContext::setBlockDescriptorType(QualType T) {
3132  const RecordType *Rec = T->getAs<RecordType>();
3133  assert(Rec && "Invalid BlockDescriptorType");
3134  BlockDescriptorType = Rec->getDecl();
3135}
3136
3137QualType ASTContext::getBlockDescriptorExtendedType() {
3138  if (BlockDescriptorExtendedType)
3139    return getTagDeclType(BlockDescriptorExtendedType);
3140
3141  RecordDecl *T;
3142  // FIXME: Needs the FlagAppleBlock bit.
3143  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3144                       &Idents.get("__block_descriptor_withcopydispose"));
3145  T->startDefinition();
3146
3147  QualType FieldTypes[] = {
3148    UnsignedLongTy,
3149    UnsignedLongTy,
3150    getPointerType(VoidPtrTy),
3151    getPointerType(VoidPtrTy)
3152  };
3153
3154  const char *FieldNames[] = {
3155    "reserved",
3156    "Size",
3157    "CopyFuncPtr",
3158    "DestroyFuncPtr"
3159  };
3160
3161  for (size_t i = 0; i < 4; ++i) {
3162    FieldDecl *Field = FieldDecl::Create(*this,
3163                                         T,
3164                                         SourceLocation(),
3165                                         &Idents.get(FieldNames[i]),
3166                                         FieldTypes[i], /*TInfo=*/0,
3167                                         /*BitWidth=*/0,
3168                                         /*Mutable=*/false);
3169    Field->setAccess(AS_public);
3170    T->addDecl(Field);
3171  }
3172
3173  T->completeDefinition();
3174
3175  BlockDescriptorExtendedType = T;
3176
3177  return getTagDeclType(BlockDescriptorExtendedType);
3178}
3179
3180void ASTContext::setBlockDescriptorExtendedType(QualType T) {
3181  const RecordType *Rec = T->getAs<RecordType>();
3182  assert(Rec && "Invalid BlockDescriptorType");
3183  BlockDescriptorExtendedType = Rec->getDecl();
3184}
3185
3186bool ASTContext::BlockRequiresCopying(QualType Ty) {
3187  if (Ty->isBlockPointerType())
3188    return true;
3189  if (isObjCNSObjectType(Ty))
3190    return true;
3191  if (Ty->isObjCObjectPointerType())
3192    return true;
3193  return false;
3194}
3195
3196QualType ASTContext::BuildByRefType(const char *DeclName, QualType Ty) {
3197  //  type = struct __Block_byref_1_X {
3198  //    void *__isa;
3199  //    struct __Block_byref_1_X *__forwarding;
3200  //    unsigned int __flags;
3201  //    unsigned int __size;
3202  //    void *__copy_helper;		// as needed
3203  //    void *__destroy_help		// as needed
3204  //    int X;
3205  //  } *
3206
3207  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3208
3209  // FIXME: Move up
3210  llvm::SmallString<36> Name;
3211  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3212                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3213  RecordDecl *T;
3214  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3215                       &Idents.get(Name.str()));
3216  T->startDefinition();
3217  QualType Int32Ty = IntTy;
3218  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3219  QualType FieldTypes[] = {
3220    getPointerType(VoidPtrTy),
3221    getPointerType(getTagDeclType(T)),
3222    Int32Ty,
3223    Int32Ty,
3224    getPointerType(VoidPtrTy),
3225    getPointerType(VoidPtrTy),
3226    Ty
3227  };
3228
3229  const char *FieldNames[] = {
3230    "__isa",
3231    "__forwarding",
3232    "__flags",
3233    "__size",
3234    "__copy_helper",
3235    "__destroy_helper",
3236    DeclName,
3237  };
3238
3239  for (size_t i = 0; i < 7; ++i) {
3240    if (!HasCopyAndDispose && i >=4 && i <= 5)
3241      continue;
3242    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3243                                         &Idents.get(FieldNames[i]),
3244                                         FieldTypes[i], /*TInfo=*/0,
3245                                         /*BitWidth=*/0, /*Mutable=*/false);
3246    Field->setAccess(AS_public);
3247    T->addDecl(Field);
3248  }
3249
3250  T->completeDefinition();
3251
3252  return getPointerType(getTagDeclType(T));
3253}
3254
3255
3256QualType ASTContext::getBlockParmType(
3257  bool BlockHasCopyDispose,
3258  llvm::SmallVectorImpl<const Expr *> &Layout) {
3259
3260  // FIXME: Move up
3261  llvm::SmallString<36> Name;
3262  llvm::raw_svector_ostream(Name) << "__block_literal_"
3263                                  << ++UniqueBlockParmTypeID;
3264  RecordDecl *T;
3265  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3266                       &Idents.get(Name.str()));
3267  T->startDefinition();
3268  QualType FieldTypes[] = {
3269    getPointerType(VoidPtrTy),
3270    IntTy,
3271    IntTy,
3272    getPointerType(VoidPtrTy),
3273    (BlockHasCopyDispose ?
3274     getPointerType(getBlockDescriptorExtendedType()) :
3275     getPointerType(getBlockDescriptorType()))
3276  };
3277
3278  const char *FieldNames[] = {
3279    "__isa",
3280    "__flags",
3281    "__reserved",
3282    "__FuncPtr",
3283    "__descriptor"
3284  };
3285
3286  for (size_t i = 0; i < 5; ++i) {
3287    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3288                                         &Idents.get(FieldNames[i]),
3289                                         FieldTypes[i], /*TInfo=*/0,
3290                                         /*BitWidth=*/0, /*Mutable=*/false);
3291    Field->setAccess(AS_public);
3292    T->addDecl(Field);
3293  }
3294
3295  for (unsigned i = 0; i < Layout.size(); ++i) {
3296    const Expr *E = Layout[i];
3297
3298    QualType FieldType = E->getType();
3299    IdentifierInfo *FieldName = 0;
3300    if (isa<CXXThisExpr>(E)) {
3301      FieldName = &Idents.get("this");
3302    } else if (const BlockDeclRefExpr *BDRE = dyn_cast<BlockDeclRefExpr>(E)) {
3303      const ValueDecl *D = BDRE->getDecl();
3304      FieldName = D->getIdentifier();
3305      if (BDRE->isByRef())
3306        FieldType = BuildByRefType(D->getNameAsCString(), FieldType);
3307    } else {
3308      // Padding.
3309      assert(isa<ConstantArrayType>(FieldType) &&
3310             isa<DeclRefExpr>(E) &&
3311             !cast<DeclRefExpr>(E)->getDecl()->getDeclName() &&
3312             "doesn't match characteristics of padding decl");
3313    }
3314
3315    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3316                                         FieldName, FieldType, /*TInfo=*/0,
3317                                         /*BitWidth=*/0, /*Mutable=*/false);
3318    Field->setAccess(AS_public);
3319    T->addDecl(Field);
3320  }
3321
3322  T->completeDefinition();
3323
3324  return getPointerType(getTagDeclType(T));
3325}
3326
3327void ASTContext::setObjCFastEnumerationStateType(QualType T) {
3328  const RecordType *Rec = T->getAs<RecordType>();
3329  assert(Rec && "Invalid ObjCFAstEnumerationStateType");
3330  ObjCFastEnumerationStateTypeDecl = Rec->getDecl();
3331}
3332
3333// This returns true if a type has been typedefed to BOOL:
3334// typedef <type> BOOL;
3335static bool isTypeTypedefedAsBOOL(QualType T) {
3336  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3337    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3338      return II->isStr("BOOL");
3339
3340  return false;
3341}
3342
3343/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3344/// purpose.
3345CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) {
3346  CharUnits sz = getTypeSizeInChars(type);
3347
3348  // Make all integer and enum types at least as large as an int
3349  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3350    sz = std::max(sz, getTypeSizeInChars(IntTy));
3351  // Treat arrays as pointers, since that's how they're passed in.
3352  else if (type->isArrayType())
3353    sz = getTypeSizeInChars(VoidPtrTy);
3354  return sz;
3355}
3356
3357static inline
3358std::string charUnitsToString(const CharUnits &CU) {
3359  return llvm::itostr(CU.getQuantity());
3360}
3361
3362/// getObjCEncodingForBlockDecl - Return the encoded type for this block
3363/// declaration.
3364void ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr,
3365                                             std::string& S) {
3366  const BlockDecl *Decl = Expr->getBlockDecl();
3367  QualType BlockTy =
3368      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3369  // Encode result type.
3370  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3371  // Compute size of all parameters.
3372  // Start with computing size of a pointer in number of bytes.
3373  // FIXME: There might(should) be a better way of doing this computation!
3374  SourceLocation Loc;
3375  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3376  CharUnits ParmOffset = PtrSize;
3377  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3378       E = Decl->param_end(); PI != E; ++PI) {
3379    QualType PType = (*PI)->getType();
3380    CharUnits sz = getObjCEncodingTypeSize(PType);
3381    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3382    ParmOffset += sz;
3383  }
3384  // Size of the argument frame
3385  S += charUnitsToString(ParmOffset);
3386  // Block pointer and offset.
3387  S += "@?0";
3388  ParmOffset = PtrSize;
3389
3390  // Argument types.
3391  ParmOffset = PtrSize;
3392  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3393       Decl->param_end(); PI != E; ++PI) {
3394    ParmVarDecl *PVDecl = *PI;
3395    QualType PType = PVDecl->getOriginalType();
3396    if (const ArrayType *AT =
3397          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3398      // Use array's original type only if it has known number of
3399      // elements.
3400      if (!isa<ConstantArrayType>(AT))
3401        PType = PVDecl->getType();
3402    } else if (PType->isFunctionType())
3403      PType = PVDecl->getType();
3404    getObjCEncodingForType(PType, S);
3405    S += charUnitsToString(ParmOffset);
3406    ParmOffset += getObjCEncodingTypeSize(PType);
3407  }
3408}
3409
3410/// getObjCEncodingForMethodDecl - Return the encoded type for this method
3411/// declaration.
3412void ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
3413                                              std::string& S) {
3414  // FIXME: This is not very efficient.
3415  // Encode type qualifer, 'in', 'inout', etc. for the return type.
3416  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
3417  // Encode result type.
3418  getObjCEncodingForType(Decl->getResultType(), S);
3419  // Compute size of all parameters.
3420  // Start with computing size of a pointer in number of bytes.
3421  // FIXME: There might(should) be a better way of doing this computation!
3422  SourceLocation Loc;
3423  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3424  // The first two arguments (self and _cmd) are pointers; account for
3425  // their size.
3426  CharUnits ParmOffset = 2 * PtrSize;
3427  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3428       E = Decl->sel_param_end(); PI != E; ++PI) {
3429    QualType PType = (*PI)->getType();
3430    CharUnits sz = getObjCEncodingTypeSize(PType);
3431    assert (sz.isPositive() &&
3432        "getObjCEncodingForMethodDecl - Incomplete param type");
3433    ParmOffset += sz;
3434  }
3435  S += charUnitsToString(ParmOffset);
3436  S += "@0:";
3437  S += charUnitsToString(PtrSize);
3438
3439  // Argument types.
3440  ParmOffset = 2 * PtrSize;
3441  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3442       E = Decl->sel_param_end(); PI != E; ++PI) {
3443    ParmVarDecl *PVDecl = *PI;
3444    QualType PType = PVDecl->getOriginalType();
3445    if (const ArrayType *AT =
3446          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3447      // Use array's original type only if it has known number of
3448      // elements.
3449      if (!isa<ConstantArrayType>(AT))
3450        PType = PVDecl->getType();
3451    } else if (PType->isFunctionType())
3452      PType = PVDecl->getType();
3453    // Process argument qualifiers for user supplied arguments; such as,
3454    // 'in', 'inout', etc.
3455    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
3456    getObjCEncodingForType(PType, S);
3457    S += charUnitsToString(ParmOffset);
3458    ParmOffset += getObjCEncodingTypeSize(PType);
3459  }
3460}
3461
3462/// getObjCEncodingForPropertyDecl - Return the encoded type for this
3463/// property declaration. If non-NULL, Container must be either an
3464/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
3465/// NULL when getting encodings for protocol properties.
3466/// Property attributes are stored as a comma-delimited C string. The simple
3467/// attributes readonly and bycopy are encoded as single characters. The
3468/// parametrized attributes, getter=name, setter=name, and ivar=name, are
3469/// encoded as single characters, followed by an identifier. Property types
3470/// are also encoded as a parametrized attribute. The characters used to encode
3471/// these attributes are defined by the following enumeration:
3472/// @code
3473/// enum PropertyAttributes {
3474/// kPropertyReadOnly = 'R',   // property is read-only.
3475/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
3476/// kPropertyByref = '&',  // property is a reference to the value last assigned
3477/// kPropertyDynamic = 'D',    // property is dynamic
3478/// kPropertyGetter = 'G',     // followed by getter selector name
3479/// kPropertySetter = 'S',     // followed by setter selector name
3480/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
3481/// kPropertyType = 't'              // followed by old-style type encoding.
3482/// kPropertyWeak = 'W'              // 'weak' property
3483/// kPropertyStrong = 'P'            // property GC'able
3484/// kPropertyNonAtomic = 'N'         // property non-atomic
3485/// };
3486/// @endcode
3487void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
3488                                                const Decl *Container,
3489                                                std::string& S) {
3490  // Collect information from the property implementation decl(s).
3491  bool Dynamic = false;
3492  ObjCPropertyImplDecl *SynthesizePID = 0;
3493
3494  // FIXME: Duplicated code due to poor abstraction.
3495  if (Container) {
3496    if (const ObjCCategoryImplDecl *CID =
3497        dyn_cast<ObjCCategoryImplDecl>(Container)) {
3498      for (ObjCCategoryImplDecl::propimpl_iterator
3499             i = CID->propimpl_begin(), e = CID->propimpl_end();
3500           i != e; ++i) {
3501        ObjCPropertyImplDecl *PID = *i;
3502        if (PID->getPropertyDecl() == PD) {
3503          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3504            Dynamic = true;
3505          } else {
3506            SynthesizePID = PID;
3507          }
3508        }
3509      }
3510    } else {
3511      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
3512      for (ObjCCategoryImplDecl::propimpl_iterator
3513             i = OID->propimpl_begin(), e = OID->propimpl_end();
3514           i != e; ++i) {
3515        ObjCPropertyImplDecl *PID = *i;
3516        if (PID->getPropertyDecl() == PD) {
3517          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3518            Dynamic = true;
3519          } else {
3520            SynthesizePID = PID;
3521          }
3522        }
3523      }
3524    }
3525  }
3526
3527  // FIXME: This is not very efficient.
3528  S = "T";
3529
3530  // Encode result type.
3531  // GCC has some special rules regarding encoding of properties which
3532  // closely resembles encoding of ivars.
3533  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
3534                             true /* outermost type */,
3535                             true /* encoding for property */);
3536
3537  if (PD->isReadOnly()) {
3538    S += ",R";
3539  } else {
3540    switch (PD->getSetterKind()) {
3541    case ObjCPropertyDecl::Assign: break;
3542    case ObjCPropertyDecl::Copy:   S += ",C"; break;
3543    case ObjCPropertyDecl::Retain: S += ",&"; break;
3544    }
3545  }
3546
3547  // It really isn't clear at all what this means, since properties
3548  // are "dynamic by default".
3549  if (Dynamic)
3550    S += ",D";
3551
3552  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
3553    S += ",N";
3554
3555  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
3556    S += ",G";
3557    S += PD->getGetterName().getAsString();
3558  }
3559
3560  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
3561    S += ",S";
3562    S += PD->getSetterName().getAsString();
3563  }
3564
3565  if (SynthesizePID) {
3566    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
3567    S += ",V";
3568    S += OID->getNameAsString();
3569  }
3570
3571  // FIXME: OBJCGC: weak & strong
3572}
3573
3574/// getLegacyIntegralTypeEncoding -
3575/// Another legacy compatibility encoding: 32-bit longs are encoded as
3576/// 'l' or 'L' , but not always.  For typedefs, we need to use
3577/// 'i' or 'I' instead if encoding a struct field, or a pointer!
3578///
3579void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
3580  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
3581    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
3582      if (BT->getKind() == BuiltinType::ULong &&
3583          ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3584        PointeeTy = UnsignedIntTy;
3585      else
3586        if (BT->getKind() == BuiltinType::Long &&
3587            ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3588          PointeeTy = IntTy;
3589    }
3590  }
3591}
3592
3593void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
3594                                        const FieldDecl *Field) {
3595  // We follow the behavior of gcc, expanding structures which are
3596  // directly pointed to, and expanding embedded structures. Note that
3597  // these rules are sufficient to prevent recursive encoding of the
3598  // same type.
3599  getObjCEncodingForTypeImpl(T, S, true, true, Field,
3600                             true /* outermost type */);
3601}
3602
3603static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
3604    switch (T->getAs<BuiltinType>()->getKind()) {
3605    default: assert(0 && "Unhandled builtin type kind");
3606    case BuiltinType::Void:       return 'v';
3607    case BuiltinType::Bool:       return 'B';
3608    case BuiltinType::Char_U:
3609    case BuiltinType::UChar:      return 'C';
3610    case BuiltinType::UShort:     return 'S';
3611    case BuiltinType::UInt:       return 'I';
3612    case BuiltinType::ULong:
3613        return
3614          (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'L' : 'Q';
3615    case BuiltinType::UInt128:    return 'T';
3616    case BuiltinType::ULongLong:  return 'Q';
3617    case BuiltinType::Char_S:
3618    case BuiltinType::SChar:      return 'c';
3619    case BuiltinType::Short:      return 's';
3620    case BuiltinType::WChar:
3621    case BuiltinType::Int:        return 'i';
3622    case BuiltinType::Long:
3623      return
3624        (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'l' : 'q';
3625    case BuiltinType::LongLong:   return 'q';
3626    case BuiltinType::Int128:     return 't';
3627    case BuiltinType::Float:      return 'f';
3628    case BuiltinType::Double:     return 'd';
3629    case BuiltinType::LongDouble: return 'd';
3630    }
3631}
3632
3633static void EncodeBitField(const ASTContext *Context, std::string& S,
3634                           QualType T, const FieldDecl *FD) {
3635  const Expr *E = FD->getBitWidth();
3636  assert(E && "bitfield width not there - getObjCEncodingForTypeImpl");
3637  ASTContext *Ctx = const_cast<ASTContext*>(Context);
3638  S += 'b';
3639  // The NeXT runtime encodes bit fields as b followed by the number of bits.
3640  // The GNU runtime requires more information; bitfields are encoded as b,
3641  // then the offset (in bits) of the first element, then the type of the
3642  // bitfield, then the size in bits.  For example, in this structure:
3643  //
3644  // struct
3645  // {
3646  //    int integer;
3647  //    int flags:2;
3648  // };
3649  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
3650  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
3651  // information is not especially sensible, but we're stuck with it for
3652  // compatibility with GCC, although providing it breaks anything that
3653  // actually uses runtime introspection and wants to work on both runtimes...
3654  if (!Ctx->getLangOptions().NeXTRuntime) {
3655    const RecordDecl *RD = FD->getParent();
3656    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
3657    // FIXME: This same linear search is also used in ExprConstant - it might
3658    // be better if the FieldDecl stored its offset.  We'd be increasing the
3659    // size of the object slightly, but saving some time every time it is used.
3660    unsigned i = 0;
3661    for (RecordDecl::field_iterator Field = RD->field_begin(),
3662                                 FieldEnd = RD->field_end();
3663         Field != FieldEnd; (void)++Field, ++i) {
3664      if (*Field == FD)
3665        break;
3666    }
3667    S += llvm::utostr(RL.getFieldOffset(i));
3668    S += ObjCEncodingForPrimitiveKind(Context, T);
3669  }
3670  unsigned N = E->EvaluateAsInt(*Ctx).getZExtValue();
3671  S += llvm::utostr(N);
3672}
3673
3674// FIXME: Use SmallString for accumulating string.
3675void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
3676                                            bool ExpandPointedToStructures,
3677                                            bool ExpandStructures,
3678                                            const FieldDecl *FD,
3679                                            bool OutermostType,
3680                                            bool EncodingProperty) {
3681  if (T->getAs<BuiltinType>()) {
3682    if (FD && FD->isBitField())
3683      return EncodeBitField(this, S, T, FD);
3684    S += ObjCEncodingForPrimitiveKind(this, T);
3685    return;
3686  }
3687
3688  if (const ComplexType *CT = T->getAs<ComplexType>()) {
3689    S += 'j';
3690    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
3691                               false);
3692    return;
3693  }
3694
3695  // encoding for pointer or r3eference types.
3696  QualType PointeeTy;
3697  if (const PointerType *PT = T->getAs<PointerType>()) {
3698    if (PT->isObjCSelType()) {
3699      S += ':';
3700      return;
3701    }
3702    PointeeTy = PT->getPointeeType();
3703  }
3704  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3705    PointeeTy = RT->getPointeeType();
3706  if (!PointeeTy.isNull()) {
3707    bool isReadOnly = false;
3708    // For historical/compatibility reasons, the read-only qualifier of the
3709    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
3710    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
3711    // Also, do not emit the 'r' for anything but the outermost type!
3712    if (isa<TypedefType>(T.getTypePtr())) {
3713      if (OutermostType && T.isConstQualified()) {
3714        isReadOnly = true;
3715        S += 'r';
3716      }
3717    } else if (OutermostType) {
3718      QualType P = PointeeTy;
3719      while (P->getAs<PointerType>())
3720        P = P->getAs<PointerType>()->getPointeeType();
3721      if (P.isConstQualified()) {
3722        isReadOnly = true;
3723        S += 'r';
3724      }
3725    }
3726    if (isReadOnly) {
3727      // Another legacy compatibility encoding. Some ObjC qualifier and type
3728      // combinations need to be rearranged.
3729      // Rewrite "in const" from "nr" to "rn"
3730      if (llvm::StringRef(S).endswith("nr"))
3731        S.replace(S.end()-2, S.end(), "rn");
3732    }
3733
3734    if (PointeeTy->isCharType()) {
3735      // char pointer types should be encoded as '*' unless it is a
3736      // type that has been typedef'd to 'BOOL'.
3737      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
3738        S += '*';
3739        return;
3740      }
3741    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
3742      // GCC binary compat: Need to convert "struct objc_class *" to "#".
3743      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
3744        S += '#';
3745        return;
3746      }
3747      // GCC binary compat: Need to convert "struct objc_object *" to "@".
3748      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
3749        S += '@';
3750        return;
3751      }
3752      // fall through...
3753    }
3754    S += '^';
3755    getLegacyIntegralTypeEncoding(PointeeTy);
3756
3757    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
3758                               NULL);
3759    return;
3760  }
3761
3762  if (const ArrayType *AT =
3763      // Ignore type qualifiers etc.
3764        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
3765    if (isa<IncompleteArrayType>(AT)) {
3766      // Incomplete arrays are encoded as a pointer to the array element.
3767      S += '^';
3768
3769      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3770                                 false, ExpandStructures, FD);
3771    } else {
3772      S += '[';
3773
3774      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
3775        S += llvm::utostr(CAT->getSize().getZExtValue());
3776      else {
3777        //Variable length arrays are encoded as a regular array with 0 elements.
3778        assert(isa<VariableArrayType>(AT) && "Unknown array type!");
3779        S += '0';
3780      }
3781
3782      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3783                                 false, ExpandStructures, FD);
3784      S += ']';
3785    }
3786    return;
3787  }
3788
3789  if (T->getAs<FunctionType>()) {
3790    S += '?';
3791    return;
3792  }
3793
3794  if (const RecordType *RTy = T->getAs<RecordType>()) {
3795    RecordDecl *RDecl = RTy->getDecl();
3796    S += RDecl->isUnion() ? '(' : '{';
3797    // Anonymous structures print as '?'
3798    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
3799      S += II->getName();
3800      if (ClassTemplateSpecializationDecl *Spec
3801          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
3802        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
3803        std::string TemplateArgsStr
3804          = TemplateSpecializationType::PrintTemplateArgumentList(
3805                                            TemplateArgs.getFlatArgumentList(),
3806                                            TemplateArgs.flat_size(),
3807                                            (*this).PrintingPolicy);
3808
3809        S += TemplateArgsStr;
3810      }
3811    } else {
3812      S += '?';
3813    }
3814    if (ExpandStructures) {
3815      S += '=';
3816      for (RecordDecl::field_iterator Field = RDecl->field_begin(),
3817                                   FieldEnd = RDecl->field_end();
3818           Field != FieldEnd; ++Field) {
3819        if (FD) {
3820          S += '"';
3821          S += Field->getNameAsString();
3822          S += '"';
3823        }
3824
3825        // Special case bit-fields.
3826        if (Field->isBitField()) {
3827          getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
3828                                     (*Field));
3829        } else {
3830          QualType qt = Field->getType();
3831          getLegacyIntegralTypeEncoding(qt);
3832          getObjCEncodingForTypeImpl(qt, S, false, true,
3833                                     FD);
3834        }
3835      }
3836    }
3837    S += RDecl->isUnion() ? ')' : '}';
3838    return;
3839  }
3840
3841  if (T->isEnumeralType()) {
3842    if (FD && FD->isBitField())
3843      EncodeBitField(this, S, T, FD);
3844    else
3845      S += 'i';
3846    return;
3847  }
3848
3849  if (T->isBlockPointerType()) {
3850    S += "@?"; // Unlike a pointer-to-function, which is "^?".
3851    return;
3852  }
3853
3854  // Ignore protocol qualifiers when mangling at this level.
3855  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
3856    T = OT->getBaseType();
3857
3858  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
3859    // @encode(class_name)
3860    ObjCInterfaceDecl *OI = OIT->getDecl();
3861    S += '{';
3862    const IdentifierInfo *II = OI->getIdentifier();
3863    S += II->getName();
3864    S += '=';
3865    llvm::SmallVector<FieldDecl*, 32> RecFields;
3866    CollectObjCIvars(OI, RecFields);
3867    for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
3868      if (RecFields[i]->isBitField())
3869        getObjCEncodingForTypeImpl(RecFields[i]->getType(), S, false, true,
3870                                   RecFields[i]);
3871      else
3872        getObjCEncodingForTypeImpl(RecFields[i]->getType(), S, false, true,
3873                                   FD);
3874    }
3875    S += '}';
3876    return;
3877  }
3878
3879  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
3880    if (OPT->isObjCIdType()) {
3881      S += '@';
3882      return;
3883    }
3884
3885    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
3886      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
3887      // Since this is a binary compatibility issue, need to consult with runtime
3888      // folks. Fortunately, this is a *very* obsure construct.
3889      S += '#';
3890      return;
3891    }
3892
3893    if (OPT->isObjCQualifiedIdType()) {
3894      getObjCEncodingForTypeImpl(getObjCIdType(), S,
3895                                 ExpandPointedToStructures,
3896                                 ExpandStructures, FD);
3897      if (FD || EncodingProperty) {
3898        // Note that we do extended encoding of protocol qualifer list
3899        // Only when doing ivar or property encoding.
3900        S += '"';
3901        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3902             E = OPT->qual_end(); I != E; ++I) {
3903          S += '<';
3904          S += (*I)->getNameAsString();
3905          S += '>';
3906        }
3907        S += '"';
3908      }
3909      return;
3910    }
3911
3912    QualType PointeeTy = OPT->getPointeeType();
3913    if (!EncodingProperty &&
3914        isa<TypedefType>(PointeeTy.getTypePtr())) {
3915      // Another historical/compatibility reason.
3916      // We encode the underlying type which comes out as
3917      // {...};
3918      S += '^';
3919      getObjCEncodingForTypeImpl(PointeeTy, S,
3920                                 false, ExpandPointedToStructures,
3921                                 NULL);
3922      return;
3923    }
3924
3925    S += '@';
3926    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
3927      S += '"';
3928      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
3929      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3930           E = OPT->qual_end(); I != E; ++I) {
3931        S += '<';
3932        S += (*I)->getNameAsString();
3933        S += '>';
3934      }
3935      S += '"';
3936    }
3937    return;
3938  }
3939
3940  // gcc just blithely ignores member pointers.
3941  // TODO: maybe there should be a mangling for these
3942  if (T->getAs<MemberPointerType>())
3943    return;
3944
3945  assert(0 && "@encode for type not implemented!");
3946}
3947
3948void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
3949                                                 std::string& S) const {
3950  if (QT & Decl::OBJC_TQ_In)
3951    S += 'n';
3952  if (QT & Decl::OBJC_TQ_Inout)
3953    S += 'N';
3954  if (QT & Decl::OBJC_TQ_Out)
3955    S += 'o';
3956  if (QT & Decl::OBJC_TQ_Bycopy)
3957    S += 'O';
3958  if (QT & Decl::OBJC_TQ_Byref)
3959    S += 'R';
3960  if (QT & Decl::OBJC_TQ_Oneway)
3961    S += 'V';
3962}
3963
3964void ASTContext::setBuiltinVaListType(QualType T) {
3965  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
3966
3967  BuiltinVaListType = T;
3968}
3969
3970void ASTContext::setObjCIdType(QualType T) {
3971  ObjCIdTypedefType = T;
3972}
3973
3974void ASTContext::setObjCSelType(QualType T) {
3975  ObjCSelTypedefType = T;
3976}
3977
3978void ASTContext::setObjCProtoType(QualType QT) {
3979  ObjCProtoType = QT;
3980}
3981
3982void ASTContext::setObjCClassType(QualType T) {
3983  ObjCClassTypedefType = T;
3984}
3985
3986void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
3987  assert(ObjCConstantStringType.isNull() &&
3988         "'NSConstantString' type already set!");
3989
3990  ObjCConstantStringType = getObjCInterfaceType(Decl);
3991}
3992
3993/// \brief Retrieve the template name that corresponds to a non-empty
3994/// lookup.
3995TemplateName ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
3996                                                   UnresolvedSetIterator End) {
3997  unsigned size = End - Begin;
3998  assert(size > 1 && "set is not overloaded!");
3999
4000  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4001                          size * sizeof(FunctionTemplateDecl*));
4002  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4003
4004  NamedDecl **Storage = OT->getStorage();
4005  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4006    NamedDecl *D = *I;
4007    assert(isa<FunctionTemplateDecl>(D) ||
4008           (isa<UsingShadowDecl>(D) &&
4009            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4010    *Storage++ = D;
4011  }
4012
4013  return TemplateName(OT);
4014}
4015
4016/// \brief Retrieve the template name that represents a qualified
4017/// template name such as \c std::vector.
4018TemplateName ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4019                                                  bool TemplateKeyword,
4020                                                  TemplateDecl *Template) {
4021  // FIXME: Canonicalization?
4022  llvm::FoldingSetNodeID ID;
4023  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4024
4025  void *InsertPos = 0;
4026  QualifiedTemplateName *QTN =
4027    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4028  if (!QTN) {
4029    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4030    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4031  }
4032
4033  return TemplateName(QTN);
4034}
4035
4036/// \brief Retrieve the template name that represents a dependent
4037/// template name such as \c MetaFun::template apply.
4038TemplateName ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4039                                                  const IdentifierInfo *Name) {
4040  assert((!NNS || NNS->isDependent()) &&
4041         "Nested name specifier must be dependent");
4042
4043  llvm::FoldingSetNodeID ID;
4044  DependentTemplateName::Profile(ID, NNS, Name);
4045
4046  void *InsertPos = 0;
4047  DependentTemplateName *QTN =
4048    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4049
4050  if (QTN)
4051    return TemplateName(QTN);
4052
4053  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4054  if (CanonNNS == NNS) {
4055    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4056  } else {
4057    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4058    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4059    DependentTemplateName *CheckQTN =
4060      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4061    assert(!CheckQTN && "Dependent type name canonicalization broken");
4062    (void)CheckQTN;
4063  }
4064
4065  DependentTemplateNames.InsertNode(QTN, InsertPos);
4066  return TemplateName(QTN);
4067}
4068
4069/// \brief Retrieve the template name that represents a dependent
4070/// template name such as \c MetaFun::template operator+.
4071TemplateName
4072ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4073                                     OverloadedOperatorKind Operator) {
4074  assert((!NNS || NNS->isDependent()) &&
4075         "Nested name specifier must be dependent");
4076
4077  llvm::FoldingSetNodeID ID;
4078  DependentTemplateName::Profile(ID, NNS, Operator);
4079
4080  void *InsertPos = 0;
4081  DependentTemplateName *QTN
4082    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4083
4084  if (QTN)
4085    return TemplateName(QTN);
4086
4087  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4088  if (CanonNNS == NNS) {
4089    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4090  } else {
4091    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4092    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4093
4094    DependentTemplateName *CheckQTN
4095      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4096    assert(!CheckQTN && "Dependent template name canonicalization broken");
4097    (void)CheckQTN;
4098  }
4099
4100  DependentTemplateNames.InsertNode(QTN, InsertPos);
4101  return TemplateName(QTN);
4102}
4103
4104/// getFromTargetType - Given one of the integer types provided by
4105/// TargetInfo, produce the corresponding type. The unsigned @p Type
4106/// is actually a value of type @c TargetInfo::IntType.
4107CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4108  switch (Type) {
4109  case TargetInfo::NoInt: return CanQualType();
4110  case TargetInfo::SignedShort: return ShortTy;
4111  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4112  case TargetInfo::SignedInt: return IntTy;
4113  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4114  case TargetInfo::SignedLong: return LongTy;
4115  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4116  case TargetInfo::SignedLongLong: return LongLongTy;
4117  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4118  }
4119
4120  assert(false && "Unhandled TargetInfo::IntType value");
4121  return CanQualType();
4122}
4123
4124//===----------------------------------------------------------------------===//
4125//                        Type Predicates.
4126//===----------------------------------------------------------------------===//
4127
4128/// isObjCNSObjectType - Return true if this is an NSObject object using
4129/// NSObject attribute on a c-style pointer type.
4130/// FIXME - Make it work directly on types.
4131/// FIXME: Move to Type.
4132///
4133bool ASTContext::isObjCNSObjectType(QualType Ty) const {
4134  if (TypedefType *TDT = dyn_cast<TypedefType>(Ty)) {
4135    if (TypedefDecl *TD = TDT->getDecl())
4136      if (TD->getAttr<ObjCNSObjectAttr>())
4137        return true;
4138  }
4139  return false;
4140}
4141
4142/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4143/// garbage collection attribute.
4144///
4145Qualifiers::GC ASTContext::getObjCGCAttrKind(const QualType &Ty) const {
4146  Qualifiers::GC GCAttrs = Qualifiers::GCNone;
4147  if (getLangOptions().ObjC1 &&
4148      getLangOptions().getGCMode() != LangOptions::NonGC) {
4149    GCAttrs = Ty.getObjCGCAttr();
4150    // Default behavious under objective-c's gc is for objective-c pointers
4151    // (or pointers to them) be treated as though they were declared
4152    // as __strong.
4153    if (GCAttrs == Qualifiers::GCNone) {
4154      if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4155        GCAttrs = Qualifiers::Strong;
4156      else if (Ty->isPointerType())
4157        return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4158    }
4159    // Non-pointers have none gc'able attribute regardless of the attribute
4160    // set on them.
4161    else if (!Ty->isAnyPointerType() && !Ty->isBlockPointerType())
4162      return Qualifiers::GCNone;
4163  }
4164  return GCAttrs;
4165}
4166
4167//===----------------------------------------------------------------------===//
4168//                        Type Compatibility Testing
4169//===----------------------------------------------------------------------===//
4170
4171/// areCompatVectorTypes - Return true if the two specified vector types are
4172/// compatible.
4173static bool areCompatVectorTypes(const VectorType *LHS,
4174                                 const VectorType *RHS) {
4175  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
4176  return LHS->getElementType() == RHS->getElementType() &&
4177         LHS->getNumElements() == RHS->getNumElements();
4178}
4179
4180bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
4181                                          QualType SecondVec) {
4182  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
4183  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
4184
4185  if (hasSameUnqualifiedType(FirstVec, SecondVec))
4186    return true;
4187
4188  // AltiVec vectors types are identical to equivalent GCC vector types
4189  const VectorType *First = FirstVec->getAs<VectorType>();
4190  const VectorType *Second = SecondVec->getAs<VectorType>();
4191  if ((((First->getAltiVecSpecific() == VectorType::AltiVec) &&
4192        (Second->getAltiVecSpecific() == VectorType::NotAltiVec)) ||
4193       ((First->getAltiVecSpecific() == VectorType::NotAltiVec) &&
4194        (Second->getAltiVecSpecific() == VectorType::AltiVec))) &&
4195      hasSameType(First->getElementType(), Second->getElementType()) &&
4196      (First->getNumElements() == Second->getNumElements()))
4197    return true;
4198
4199  return false;
4200}
4201
4202//===----------------------------------------------------------------------===//
4203// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
4204//===----------------------------------------------------------------------===//
4205
4206/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
4207/// inheritance hierarchy of 'rProto'.
4208bool ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
4209                                                ObjCProtocolDecl *rProto) {
4210  if (lProto == rProto)
4211    return true;
4212  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
4213       E = rProto->protocol_end(); PI != E; ++PI)
4214    if (ProtocolCompatibleWithProtocol(lProto, *PI))
4215      return true;
4216  return false;
4217}
4218
4219/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
4220/// return true if lhs's protocols conform to rhs's protocol; false
4221/// otherwise.
4222bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
4223  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
4224    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
4225  return false;
4226}
4227
4228/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
4229/// Class<p1, ...>.
4230bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
4231                                                      QualType rhs) {
4232  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
4233  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4234  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
4235
4236  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4237       E = lhsQID->qual_end(); I != E; ++I) {
4238    bool match = false;
4239    ObjCProtocolDecl *lhsProto = *I;
4240    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4241         E = rhsOPT->qual_end(); J != E; ++J) {
4242      ObjCProtocolDecl *rhsProto = *J;
4243      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
4244        match = true;
4245        break;
4246      }
4247    }
4248    if (!match)
4249      return false;
4250  }
4251  return true;
4252}
4253
4254/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
4255/// ObjCQualifiedIDType.
4256bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
4257                                                   bool compare) {
4258  // Allow id<P..> and an 'id' or void* type in all cases.
4259  if (lhs->isVoidPointerType() ||
4260      lhs->isObjCIdType() || lhs->isObjCClassType())
4261    return true;
4262  else if (rhs->isVoidPointerType() ||
4263           rhs->isObjCIdType() || rhs->isObjCClassType())
4264    return true;
4265
4266  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
4267    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4268
4269    if (!rhsOPT) return false;
4270
4271    if (rhsOPT->qual_empty()) {
4272      // If the RHS is a unqualified interface pointer "NSString*",
4273      // make sure we check the class hierarchy.
4274      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4275        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4276             E = lhsQID->qual_end(); I != E; ++I) {
4277          // when comparing an id<P> on lhs with a static type on rhs,
4278          // see if static class implements all of id's protocols, directly or
4279          // through its super class and categories.
4280          if (!rhsID->ClassImplementsProtocol(*I, true))
4281            return false;
4282        }
4283      }
4284      // If there are no qualifiers and no interface, we have an 'id'.
4285      return true;
4286    }
4287    // Both the right and left sides have qualifiers.
4288    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4289         E = lhsQID->qual_end(); I != E; ++I) {
4290      ObjCProtocolDecl *lhsProto = *I;
4291      bool match = false;
4292
4293      // when comparing an id<P> on lhs with a static type on rhs,
4294      // see if static class implements all of id's protocols, directly or
4295      // through its super class and categories.
4296      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4297           E = rhsOPT->qual_end(); J != E; ++J) {
4298        ObjCProtocolDecl *rhsProto = *J;
4299        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4300            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4301          match = true;
4302          break;
4303        }
4304      }
4305      // If the RHS is a qualified interface pointer "NSString<P>*",
4306      // make sure we check the class hierarchy.
4307      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4308        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4309             E = lhsQID->qual_end(); I != E; ++I) {
4310          // when comparing an id<P> on lhs with a static type on rhs,
4311          // see if static class implements all of id's protocols, directly or
4312          // through its super class and categories.
4313          if (rhsID->ClassImplementsProtocol(*I, true)) {
4314            match = true;
4315            break;
4316          }
4317        }
4318      }
4319      if (!match)
4320        return false;
4321    }
4322
4323    return true;
4324  }
4325
4326  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
4327  assert(rhsQID && "One of the LHS/RHS should be id<x>");
4328
4329  if (const ObjCObjectPointerType *lhsOPT =
4330        lhs->getAsObjCInterfacePointerType()) {
4331    if (lhsOPT->qual_empty()) {
4332      bool match = false;
4333      if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
4334        for (ObjCObjectPointerType::qual_iterator I = rhsQID->qual_begin(),
4335             E = rhsQID->qual_end(); I != E; ++I) {
4336          // when comparing an id<P> on rhs with a static type on lhs,
4337          // static class must implement all of id's protocols directly or
4338          // indirectly through its super class.
4339          if (lhsID->ClassImplementsProtocol(*I, true)) {
4340            match = true;
4341            break;
4342          }
4343        }
4344        if (!match)
4345          return false;
4346      }
4347      return true;
4348    }
4349    // Both the right and left sides have qualifiers.
4350    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
4351         E = lhsOPT->qual_end(); I != E; ++I) {
4352      ObjCProtocolDecl *lhsProto = *I;
4353      bool match = false;
4354
4355      // when comparing an id<P> on lhs with a static type on rhs,
4356      // see if static class implements all of id's protocols, directly or
4357      // through its super class and categories.
4358      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4359           E = rhsQID->qual_end(); J != E; ++J) {
4360        ObjCProtocolDecl *rhsProto = *J;
4361        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4362            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4363          match = true;
4364          break;
4365        }
4366      }
4367      if (!match)
4368        return false;
4369    }
4370    return true;
4371  }
4372  return false;
4373}
4374
4375/// canAssignObjCInterfaces - Return true if the two interface types are
4376/// compatible for assignment from RHS to LHS.  This handles validation of any
4377/// protocol qualifiers on the LHS or RHS.
4378///
4379bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
4380                                         const ObjCObjectPointerType *RHSOPT) {
4381  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4382  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4383
4384  // If either type represents the built-in 'id' or 'Class' types, return true.
4385  if (LHS->isObjCUnqualifiedIdOrClass() ||
4386      RHS->isObjCUnqualifiedIdOrClass())
4387    return true;
4388
4389  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
4390    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4391                                             QualType(RHSOPT,0),
4392                                             false);
4393
4394  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
4395    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
4396                                                QualType(RHSOPT,0));
4397
4398  // If we have 2 user-defined types, fall into that path.
4399  if (LHS->getInterface() && RHS->getInterface())
4400    return canAssignObjCInterfaces(LHS, RHS);
4401
4402  return false;
4403}
4404
4405/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
4406/// for providing type-safty for objective-c pointers used to pass/return
4407/// arguments in block literals. When passed as arguments, passing 'A*' where
4408/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
4409/// not OK. For the return type, the opposite is not OK.
4410bool ASTContext::canAssignObjCInterfacesInBlockPointer(
4411                                         const ObjCObjectPointerType *LHSOPT,
4412                                         const ObjCObjectPointerType *RHSOPT) {
4413  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
4414    return true;
4415
4416  if (LHSOPT->isObjCBuiltinType()) {
4417    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
4418  }
4419
4420  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
4421    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4422                                             QualType(RHSOPT,0),
4423                                             false);
4424
4425  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
4426  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
4427  if (LHS && RHS)  { // We have 2 user-defined types.
4428    if (LHS != RHS) {
4429      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
4430        return false;
4431      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
4432        return true;
4433    }
4434    else
4435      return true;
4436  }
4437  return false;
4438}
4439
4440/// getIntersectionOfProtocols - This routine finds the intersection of set
4441/// of protocols inherited from two distinct objective-c pointer objects.
4442/// It is used to build composite qualifier list of the composite type of
4443/// the conditional expression involving two objective-c pointer objects.
4444static
4445void getIntersectionOfProtocols(ASTContext &Context,
4446                                const ObjCObjectPointerType *LHSOPT,
4447                                const ObjCObjectPointerType *RHSOPT,
4448      llvm::SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
4449
4450  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4451  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4452  assert(LHS->getInterface() && "LHS must have an interface base");
4453  assert(RHS->getInterface() && "RHS must have an interface base");
4454
4455  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
4456  unsigned LHSNumProtocols = LHS->getNumProtocols();
4457  if (LHSNumProtocols > 0)
4458    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
4459  else {
4460    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4461    Context.CollectInheritedProtocols(LHS->getInterface(),
4462                                      LHSInheritedProtocols);
4463    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
4464                                LHSInheritedProtocols.end());
4465  }
4466
4467  unsigned RHSNumProtocols = RHS->getNumProtocols();
4468  if (RHSNumProtocols > 0) {
4469    ObjCProtocolDecl **RHSProtocols =
4470      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
4471    for (unsigned i = 0; i < RHSNumProtocols; ++i)
4472      if (InheritedProtocolSet.count(RHSProtocols[i]))
4473        IntersectionOfProtocols.push_back(RHSProtocols[i]);
4474  }
4475  else {
4476    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
4477    Context.CollectInheritedProtocols(RHS->getInterface(),
4478                                      RHSInheritedProtocols);
4479    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4480         RHSInheritedProtocols.begin(),
4481         E = RHSInheritedProtocols.end(); I != E; ++I)
4482      if (InheritedProtocolSet.count((*I)))
4483        IntersectionOfProtocols.push_back((*I));
4484  }
4485}
4486
4487/// areCommonBaseCompatible - Returns common base class of the two classes if
4488/// one found. Note that this is O'2 algorithm. But it will be called as the
4489/// last type comparison in a ?-exp of ObjC pointer types before a
4490/// warning is issued. So, its invokation is extremely rare.
4491QualType ASTContext::areCommonBaseCompatible(
4492                                          const ObjCObjectPointerType *Lptr,
4493                                          const ObjCObjectPointerType *Rptr) {
4494  const ObjCObjectType *LHS = Lptr->getObjectType();
4495  const ObjCObjectType *RHS = Rptr->getObjectType();
4496  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
4497  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
4498  if (!LDecl || !RDecl)
4499    return QualType();
4500
4501  while ((LDecl = LDecl->getSuperClass())) {
4502    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
4503    if (canAssignObjCInterfaces(LHS, RHS)) {
4504      llvm::SmallVector<ObjCProtocolDecl *, 8> Protocols;
4505      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
4506
4507      QualType Result = QualType(LHS, 0);
4508      if (!Protocols.empty())
4509        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
4510      Result = getObjCObjectPointerType(Result);
4511      return Result;
4512    }
4513  }
4514
4515  return QualType();
4516}
4517
4518bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
4519                                         const ObjCObjectType *RHS) {
4520  assert(LHS->getInterface() && "LHS is not an interface type");
4521  assert(RHS->getInterface() && "RHS is not an interface type");
4522
4523  // Verify that the base decls are compatible: the RHS must be a subclass of
4524  // the LHS.
4525  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
4526    return false;
4527
4528  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
4529  // protocol qualified at all, then we are good.
4530  if (LHS->getNumProtocols() == 0)
4531    return true;
4532
4533  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't, then it
4534  // isn't a superset.
4535  if (RHS->getNumProtocols() == 0)
4536    return true;  // FIXME: should return false!
4537
4538  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
4539                                     LHSPE = LHS->qual_end();
4540       LHSPI != LHSPE; LHSPI++) {
4541    bool RHSImplementsProtocol = false;
4542
4543    // If the RHS doesn't implement the protocol on the left, the types
4544    // are incompatible.
4545    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
4546                                       RHSPE = RHS->qual_end();
4547         RHSPI != RHSPE; RHSPI++) {
4548      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
4549        RHSImplementsProtocol = true;
4550        break;
4551      }
4552    }
4553    // FIXME: For better diagnostics, consider passing back the protocol name.
4554    if (!RHSImplementsProtocol)
4555      return false;
4556  }
4557  // The RHS implements all protocols listed on the LHS.
4558  return true;
4559}
4560
4561bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
4562  // get the "pointed to" types
4563  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
4564  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
4565
4566  if (!LHSOPT || !RHSOPT)
4567    return false;
4568
4569  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
4570         canAssignObjCInterfaces(RHSOPT, LHSOPT);
4571}
4572
4573bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
4574  return canAssignObjCInterfaces(
4575                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
4576                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
4577}
4578
4579/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
4580/// both shall have the identically qualified version of a compatible type.
4581/// C99 6.2.7p1: Two types have compatible types if their types are the
4582/// same. See 6.7.[2,3,5] for additional rules.
4583bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
4584                                    bool CompareUnqualified) {
4585  if (getLangOptions().CPlusPlus)
4586    return hasSameType(LHS, RHS);
4587
4588  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
4589}
4590
4591bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
4592  return !mergeTypes(LHS, RHS, true).isNull();
4593}
4594
4595QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
4596                                        bool OfBlockPointer,
4597                                        bool Unqualified) {
4598  const FunctionType *lbase = lhs->getAs<FunctionType>();
4599  const FunctionType *rbase = rhs->getAs<FunctionType>();
4600  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
4601  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
4602  bool allLTypes = true;
4603  bool allRTypes = true;
4604
4605  // Check return type
4606  QualType retType;
4607  if (OfBlockPointer)
4608    retType = mergeTypes(rbase->getResultType(), lbase->getResultType(), true,
4609                         Unqualified);
4610  else
4611   retType = mergeTypes(lbase->getResultType(), rbase->getResultType(),
4612                        false, Unqualified);
4613  if (retType.isNull()) return QualType();
4614
4615  if (Unqualified)
4616    retType = retType.getUnqualifiedType();
4617
4618  CanQualType LRetType = getCanonicalType(lbase->getResultType());
4619  CanQualType RRetType = getCanonicalType(rbase->getResultType());
4620  if (Unqualified) {
4621    LRetType = LRetType.getUnqualifiedType();
4622    RRetType = RRetType.getUnqualifiedType();
4623  }
4624
4625  if (getCanonicalType(retType) != LRetType)
4626    allLTypes = false;
4627  if (getCanonicalType(retType) != RRetType)
4628    allRTypes = false;
4629  // FIXME: double check this
4630  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
4631  //                           rbase->getRegParmAttr() != 0 &&
4632  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
4633  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
4634  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
4635  unsigned RegParm = lbaseInfo.getRegParm() == 0 ? rbaseInfo.getRegParm() :
4636      lbaseInfo.getRegParm();
4637  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
4638  if (NoReturn != lbaseInfo.getNoReturn() ||
4639      RegParm != lbaseInfo.getRegParm())
4640    allLTypes = false;
4641  if (NoReturn != rbaseInfo.getNoReturn() ||
4642      RegParm != rbaseInfo.getRegParm())
4643    allRTypes = false;
4644  CallingConv lcc = lbaseInfo.getCC();
4645  CallingConv rcc = rbaseInfo.getCC();
4646  // Compatible functions must have compatible calling conventions
4647  if (!isSameCallConv(lcc, rcc))
4648    return QualType();
4649
4650  if (lproto && rproto) { // two C99 style function prototypes
4651    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
4652           "C++ shouldn't be here");
4653    unsigned lproto_nargs = lproto->getNumArgs();
4654    unsigned rproto_nargs = rproto->getNumArgs();
4655
4656    // Compatible functions must have the same number of arguments
4657    if (lproto_nargs != rproto_nargs)
4658      return QualType();
4659
4660    // Variadic and non-variadic functions aren't compatible
4661    if (lproto->isVariadic() != rproto->isVariadic())
4662      return QualType();
4663
4664    if (lproto->getTypeQuals() != rproto->getTypeQuals())
4665      return QualType();
4666
4667    // Check argument compatibility
4668    llvm::SmallVector<QualType, 10> types;
4669    for (unsigned i = 0; i < lproto_nargs; i++) {
4670      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
4671      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
4672      QualType argtype = mergeTypes(largtype, rargtype, OfBlockPointer,
4673                                    Unqualified);
4674      if (argtype.isNull()) return QualType();
4675
4676      if (Unqualified)
4677        argtype = argtype.getUnqualifiedType();
4678
4679      types.push_back(argtype);
4680      if (Unqualified) {
4681        largtype = largtype.getUnqualifiedType();
4682        rargtype = rargtype.getUnqualifiedType();
4683      }
4684
4685      if (getCanonicalType(argtype) != getCanonicalType(largtype))
4686        allLTypes = false;
4687      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
4688        allRTypes = false;
4689    }
4690    if (allLTypes) return lhs;
4691    if (allRTypes) return rhs;
4692    return getFunctionType(retType, types.begin(), types.size(),
4693                           lproto->isVariadic(), lproto->getTypeQuals(),
4694                           false, false, 0, 0,
4695                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4696  }
4697
4698  if (lproto) allRTypes = false;
4699  if (rproto) allLTypes = false;
4700
4701  const FunctionProtoType *proto = lproto ? lproto : rproto;
4702  if (proto) {
4703    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
4704    if (proto->isVariadic()) return QualType();
4705    // Check that the types are compatible with the types that
4706    // would result from default argument promotions (C99 6.7.5.3p15).
4707    // The only types actually affected are promotable integer
4708    // types and floats, which would be passed as a different
4709    // type depending on whether the prototype is visible.
4710    unsigned proto_nargs = proto->getNumArgs();
4711    for (unsigned i = 0; i < proto_nargs; ++i) {
4712      QualType argTy = proto->getArgType(i);
4713
4714      // Look at the promotion type of enum types, since that is the type used
4715      // to pass enum values.
4716      if (const EnumType *Enum = argTy->getAs<EnumType>())
4717        argTy = Enum->getDecl()->getPromotionType();
4718
4719      if (argTy->isPromotableIntegerType() ||
4720          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
4721        return QualType();
4722    }
4723
4724    if (allLTypes) return lhs;
4725    if (allRTypes) return rhs;
4726    return getFunctionType(retType, proto->arg_type_begin(),
4727                           proto->getNumArgs(), proto->isVariadic(),
4728                           proto->getTypeQuals(),
4729                           false, false, 0, 0,
4730                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4731  }
4732
4733  if (allLTypes) return lhs;
4734  if (allRTypes) return rhs;
4735  FunctionType::ExtInfo Info(NoReturn, RegParm, lcc);
4736  return getFunctionNoProtoType(retType, Info);
4737}
4738
4739QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
4740                                bool OfBlockPointer,
4741                                bool Unqualified) {
4742  // C++ [expr]: If an expression initially has the type "reference to T", the
4743  // type is adjusted to "T" prior to any further analysis, the expression
4744  // designates the object or function denoted by the reference, and the
4745  // expression is an lvalue unless the reference is an rvalue reference and
4746  // the expression is a function call (possibly inside parentheses).
4747  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
4748  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
4749
4750  if (Unqualified) {
4751    LHS = LHS.getUnqualifiedType();
4752    RHS = RHS.getUnqualifiedType();
4753  }
4754
4755  QualType LHSCan = getCanonicalType(LHS),
4756           RHSCan = getCanonicalType(RHS);
4757
4758  // If two types are identical, they are compatible.
4759  if (LHSCan == RHSCan)
4760    return LHS;
4761
4762  // If the qualifiers are different, the types aren't compatible... mostly.
4763  Qualifiers LQuals = LHSCan.getLocalQualifiers();
4764  Qualifiers RQuals = RHSCan.getLocalQualifiers();
4765  if (LQuals != RQuals) {
4766    // If any of these qualifiers are different, we have a type
4767    // mismatch.
4768    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
4769        LQuals.getAddressSpace() != RQuals.getAddressSpace())
4770      return QualType();
4771
4772    // Exactly one GC qualifier difference is allowed: __strong is
4773    // okay if the other type has no GC qualifier but is an Objective
4774    // C object pointer (i.e. implicitly strong by default).  We fix
4775    // this by pretending that the unqualified type was actually
4776    // qualified __strong.
4777    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
4778    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
4779    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
4780
4781    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
4782      return QualType();
4783
4784    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
4785      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
4786    }
4787    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
4788      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
4789    }
4790    return QualType();
4791  }
4792
4793  // Okay, qualifiers are equal.
4794
4795  Type::TypeClass LHSClass = LHSCan->getTypeClass();
4796  Type::TypeClass RHSClass = RHSCan->getTypeClass();
4797
4798  // We want to consider the two function types to be the same for these
4799  // comparisons, just force one to the other.
4800  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
4801  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
4802
4803  // Same as above for arrays
4804  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
4805    LHSClass = Type::ConstantArray;
4806  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
4807    RHSClass = Type::ConstantArray;
4808
4809  // ObjCInterfaces are just specialized ObjCObjects.
4810  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
4811  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
4812
4813  // Canonicalize ExtVector -> Vector.
4814  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
4815  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
4816
4817  // If the canonical type classes don't match.
4818  if (LHSClass != RHSClass) {
4819    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
4820    // a signed integer type, or an unsigned integer type.
4821    // Compatibility is based on the underlying type, not the promotion
4822    // type.
4823    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
4824      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
4825        return RHS;
4826    }
4827    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
4828      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
4829        return LHS;
4830    }
4831
4832    return QualType();
4833  }
4834
4835  // The canonical type classes match.
4836  switch (LHSClass) {
4837#define TYPE(Class, Base)
4838#define ABSTRACT_TYPE(Class, Base)
4839#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
4840#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
4841#define DEPENDENT_TYPE(Class, Base) case Type::Class:
4842#include "clang/AST/TypeNodes.def"
4843    assert(false && "Non-canonical and dependent types shouldn't get here");
4844    return QualType();
4845
4846  case Type::LValueReference:
4847  case Type::RValueReference:
4848  case Type::MemberPointer:
4849    assert(false && "C++ should never be in mergeTypes");
4850    return QualType();
4851
4852  case Type::ObjCInterface:
4853  case Type::IncompleteArray:
4854  case Type::VariableArray:
4855  case Type::FunctionProto:
4856  case Type::ExtVector:
4857    assert(false && "Types are eliminated above");
4858    return QualType();
4859
4860  case Type::Pointer:
4861  {
4862    // Merge two pointer types, while trying to preserve typedef info
4863    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
4864    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
4865    if (Unqualified) {
4866      LHSPointee = LHSPointee.getUnqualifiedType();
4867      RHSPointee = RHSPointee.getUnqualifiedType();
4868    }
4869    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
4870                                     Unqualified);
4871    if (ResultType.isNull()) return QualType();
4872    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
4873      return LHS;
4874    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
4875      return RHS;
4876    return getPointerType(ResultType);
4877  }
4878  case Type::BlockPointer:
4879  {
4880    // Merge two block pointer types, while trying to preserve typedef info
4881    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
4882    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
4883    if (Unqualified) {
4884      LHSPointee = LHSPointee.getUnqualifiedType();
4885      RHSPointee = RHSPointee.getUnqualifiedType();
4886    }
4887    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
4888                                     Unqualified);
4889    if (ResultType.isNull()) return QualType();
4890    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
4891      return LHS;
4892    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
4893      return RHS;
4894    return getBlockPointerType(ResultType);
4895  }
4896  case Type::ConstantArray:
4897  {
4898    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
4899    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
4900    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
4901      return QualType();
4902
4903    QualType LHSElem = getAsArrayType(LHS)->getElementType();
4904    QualType RHSElem = getAsArrayType(RHS)->getElementType();
4905    if (Unqualified) {
4906      LHSElem = LHSElem.getUnqualifiedType();
4907      RHSElem = RHSElem.getUnqualifiedType();
4908    }
4909
4910    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
4911    if (ResultType.isNull()) return QualType();
4912    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
4913      return LHS;
4914    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
4915      return RHS;
4916    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
4917                                          ArrayType::ArraySizeModifier(), 0);
4918    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
4919                                          ArrayType::ArraySizeModifier(), 0);
4920    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
4921    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
4922    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
4923      return LHS;
4924    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
4925      return RHS;
4926    if (LVAT) {
4927      // FIXME: This isn't correct! But tricky to implement because
4928      // the array's size has to be the size of LHS, but the type
4929      // has to be different.
4930      return LHS;
4931    }
4932    if (RVAT) {
4933      // FIXME: This isn't correct! But tricky to implement because
4934      // the array's size has to be the size of RHS, but the type
4935      // has to be different.
4936      return RHS;
4937    }
4938    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
4939    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
4940    return getIncompleteArrayType(ResultType,
4941                                  ArrayType::ArraySizeModifier(), 0);
4942  }
4943  case Type::FunctionNoProto:
4944    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
4945  case Type::Record:
4946  case Type::Enum:
4947    return QualType();
4948  case Type::Builtin:
4949    // Only exactly equal builtin types are compatible, which is tested above.
4950    return QualType();
4951  case Type::Complex:
4952    // Distinct complex types are incompatible.
4953    return QualType();
4954  case Type::Vector:
4955    // FIXME: The merged type should be an ExtVector!
4956    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
4957                             RHSCan->getAs<VectorType>()))
4958      return LHS;
4959    return QualType();
4960  case Type::ObjCObject: {
4961    // Check if the types are assignment compatible.
4962    // FIXME: This should be type compatibility, e.g. whether
4963    // "LHS x; RHS x;" at global scope is legal.
4964    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
4965    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
4966    if (canAssignObjCInterfaces(LHSIface, RHSIface))
4967      return LHS;
4968
4969    return QualType();
4970  }
4971  case Type::ObjCObjectPointer: {
4972    if (OfBlockPointer) {
4973      if (canAssignObjCInterfacesInBlockPointer(
4974                                          LHS->getAs<ObjCObjectPointerType>(),
4975                                          RHS->getAs<ObjCObjectPointerType>()))
4976      return LHS;
4977      return QualType();
4978    }
4979    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
4980                                RHS->getAs<ObjCObjectPointerType>()))
4981      return LHS;
4982
4983    return QualType();
4984    }
4985  }
4986
4987  return QualType();
4988}
4989
4990/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
4991/// 'RHS' attributes and returns the merged version; including for function
4992/// return types.
4993QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
4994  QualType LHSCan = getCanonicalType(LHS),
4995  RHSCan = getCanonicalType(RHS);
4996  // If two types are identical, they are compatible.
4997  if (LHSCan == RHSCan)
4998    return LHS;
4999  if (RHSCan->isFunctionType()) {
5000    if (!LHSCan->isFunctionType())
5001      return QualType();
5002    QualType OldReturnType =
5003      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
5004    QualType NewReturnType =
5005      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
5006    QualType ResReturnType =
5007      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
5008    if (ResReturnType.isNull())
5009      return QualType();
5010    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
5011      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
5012      // In either case, use OldReturnType to build the new function type.
5013      const FunctionType *F = LHS->getAs<FunctionType>();
5014      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
5015        FunctionType::ExtInfo Info = getFunctionExtInfo(LHS);
5016        QualType ResultType
5017          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
5018                                  FPT->getNumArgs(), FPT->isVariadic(),
5019                                  FPT->getTypeQuals(),
5020                                  FPT->hasExceptionSpec(),
5021                                  FPT->hasAnyExceptionSpec(),
5022                                  FPT->getNumExceptions(),
5023                                  FPT->exception_begin(),
5024                                  Info);
5025        return ResultType;
5026      }
5027    }
5028    return QualType();
5029  }
5030
5031  // If the qualifiers are different, the types can still be merged.
5032  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5033  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5034  if (LQuals != RQuals) {
5035    // If any of these qualifiers are different, we have a type mismatch.
5036    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5037        LQuals.getAddressSpace() != RQuals.getAddressSpace())
5038      return QualType();
5039
5040    // Exactly one GC qualifier difference is allowed: __strong is
5041    // okay if the other type has no GC qualifier but is an Objective
5042    // C object pointer (i.e. implicitly strong by default).  We fix
5043    // this by pretending that the unqualified type was actually
5044    // qualified __strong.
5045    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5046    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5047    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5048
5049    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5050      return QualType();
5051
5052    if (GC_L == Qualifiers::Strong)
5053      return LHS;
5054    if (GC_R == Qualifiers::Strong)
5055      return RHS;
5056    return QualType();
5057  }
5058
5059  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
5060    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5061    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5062    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
5063    if (ResQT == LHSBaseQT)
5064      return LHS;
5065    if (ResQT == RHSBaseQT)
5066      return RHS;
5067  }
5068  return QualType();
5069}
5070
5071//===----------------------------------------------------------------------===//
5072//                         Integer Predicates
5073//===----------------------------------------------------------------------===//
5074
5075unsigned ASTContext::getIntWidth(QualType T) {
5076  if (T->isBooleanType())
5077    return 1;
5078  if (EnumType *ET = dyn_cast<EnumType>(T))
5079    T = ET->getDecl()->getIntegerType();
5080  // For builtin types, just use the standard type sizing method
5081  return (unsigned)getTypeSize(T);
5082}
5083
5084QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
5085  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
5086
5087  // Turn <4 x signed int> -> <4 x unsigned int>
5088  if (const VectorType *VTy = T->getAs<VectorType>())
5089    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
5090             VTy->getNumElements(), VTy->getAltiVecSpecific());
5091
5092  // For enums, we return the unsigned version of the base type.
5093  if (const EnumType *ETy = T->getAs<EnumType>())
5094    T = ETy->getDecl()->getIntegerType();
5095
5096  const BuiltinType *BTy = T->getAs<BuiltinType>();
5097  assert(BTy && "Unexpected signed integer type");
5098  switch (BTy->getKind()) {
5099  case BuiltinType::Char_S:
5100  case BuiltinType::SChar:
5101    return UnsignedCharTy;
5102  case BuiltinType::Short:
5103    return UnsignedShortTy;
5104  case BuiltinType::Int:
5105    return UnsignedIntTy;
5106  case BuiltinType::Long:
5107    return UnsignedLongTy;
5108  case BuiltinType::LongLong:
5109    return UnsignedLongLongTy;
5110  case BuiltinType::Int128:
5111    return UnsignedInt128Ty;
5112  default:
5113    assert(0 && "Unexpected signed integer type");
5114    return QualType();
5115  }
5116}
5117
5118ExternalASTSource::~ExternalASTSource() { }
5119
5120void ExternalASTSource::PrintStats() { }
5121
5122
5123//===----------------------------------------------------------------------===//
5124//                          Builtin Type Computation
5125//===----------------------------------------------------------------------===//
5126
5127/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
5128/// pointer over the consumed characters.  This returns the resultant type.
5129static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
5130                                  ASTContext::GetBuiltinTypeError &Error,
5131                                  bool AllowTypeModifiers = true) {
5132  // Modifiers.
5133  int HowLong = 0;
5134  bool Signed = false, Unsigned = false;
5135
5136  // Read the modifiers first.
5137  bool Done = false;
5138  while (!Done) {
5139    switch (*Str++) {
5140    default: Done = true; --Str; break;
5141    case 'S':
5142      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
5143      assert(!Signed && "Can't use 'S' modifier multiple times!");
5144      Signed = true;
5145      break;
5146    case 'U':
5147      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
5148      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
5149      Unsigned = true;
5150      break;
5151    case 'L':
5152      assert(HowLong <= 2 && "Can't have LLLL modifier");
5153      ++HowLong;
5154      break;
5155    }
5156  }
5157
5158  QualType Type;
5159
5160  // Read the base type.
5161  switch (*Str++) {
5162  default: assert(0 && "Unknown builtin type letter!");
5163  case 'v':
5164    assert(HowLong == 0 && !Signed && !Unsigned &&
5165           "Bad modifiers used with 'v'!");
5166    Type = Context.VoidTy;
5167    break;
5168  case 'f':
5169    assert(HowLong == 0 && !Signed && !Unsigned &&
5170           "Bad modifiers used with 'f'!");
5171    Type = Context.FloatTy;
5172    break;
5173  case 'd':
5174    assert(HowLong < 2 && !Signed && !Unsigned &&
5175           "Bad modifiers used with 'd'!");
5176    if (HowLong)
5177      Type = Context.LongDoubleTy;
5178    else
5179      Type = Context.DoubleTy;
5180    break;
5181  case 's':
5182    assert(HowLong == 0 && "Bad modifiers used with 's'!");
5183    if (Unsigned)
5184      Type = Context.UnsignedShortTy;
5185    else
5186      Type = Context.ShortTy;
5187    break;
5188  case 'i':
5189    if (HowLong == 3)
5190      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
5191    else if (HowLong == 2)
5192      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
5193    else if (HowLong == 1)
5194      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
5195    else
5196      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
5197    break;
5198  case 'c':
5199    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
5200    if (Signed)
5201      Type = Context.SignedCharTy;
5202    else if (Unsigned)
5203      Type = Context.UnsignedCharTy;
5204    else
5205      Type = Context.CharTy;
5206    break;
5207  case 'b': // boolean
5208    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
5209    Type = Context.BoolTy;
5210    break;
5211  case 'z':  // size_t.
5212    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
5213    Type = Context.getSizeType();
5214    break;
5215  case 'F':
5216    Type = Context.getCFConstantStringType();
5217    break;
5218  case 'a':
5219    Type = Context.getBuiltinVaListType();
5220    assert(!Type.isNull() && "builtin va list type not initialized!");
5221    break;
5222  case 'A':
5223    // This is a "reference" to a va_list; however, what exactly
5224    // this means depends on how va_list is defined. There are two
5225    // different kinds of va_list: ones passed by value, and ones
5226    // passed by reference.  An example of a by-value va_list is
5227    // x86, where va_list is a char*. An example of by-ref va_list
5228    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
5229    // we want this argument to be a char*&; for x86-64, we want
5230    // it to be a __va_list_tag*.
5231    Type = Context.getBuiltinVaListType();
5232    assert(!Type.isNull() && "builtin va list type not initialized!");
5233    if (Type->isArrayType()) {
5234      Type = Context.getArrayDecayedType(Type);
5235    } else {
5236      Type = Context.getLValueReferenceType(Type);
5237    }
5238    break;
5239  case 'V': {
5240    char *End;
5241    unsigned NumElements = strtoul(Str, &End, 10);
5242    assert(End != Str && "Missing vector size");
5243
5244    Str = End;
5245
5246    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, false);
5247    // FIXME: Don't know what to do about AltiVec.
5248    Type = Context.getVectorType(ElementType, NumElements,
5249                                 VectorType::NotAltiVec);
5250    break;
5251  }
5252  case 'X': {
5253    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, false);
5254    Type = Context.getComplexType(ElementType);
5255    break;
5256  }
5257  case 'P':
5258    Type = Context.getFILEType();
5259    if (Type.isNull()) {
5260      Error = ASTContext::GE_Missing_stdio;
5261      return QualType();
5262    }
5263    break;
5264  case 'J':
5265    if (Signed)
5266      Type = Context.getsigjmp_bufType();
5267    else
5268      Type = Context.getjmp_bufType();
5269
5270    if (Type.isNull()) {
5271      Error = ASTContext::GE_Missing_setjmp;
5272      return QualType();
5273    }
5274    break;
5275  }
5276
5277  if (!AllowTypeModifiers)
5278    return Type;
5279
5280  Done = false;
5281  while (!Done) {
5282    switch (char c = *Str++) {
5283      default: Done = true; --Str; break;
5284      case '*':
5285      case '&':
5286        {
5287          // Both pointers and references can have their pointee types
5288          // qualified with an address space.
5289          char *End;
5290          unsigned AddrSpace = strtoul(Str, &End, 10);
5291          if (End != Str && AddrSpace != 0) {
5292            Type = Context.getAddrSpaceQualType(Type, AddrSpace);
5293            Str = End;
5294          }
5295        }
5296        if (c == '*')
5297          Type = Context.getPointerType(Type);
5298        else
5299          Type = Context.getLValueReferenceType(Type);
5300        break;
5301      // FIXME: There's no way to have a built-in with an rvalue ref arg.
5302      case 'C':
5303        Type = Type.withConst();
5304        break;
5305      case 'D':
5306        Type = Context.getVolatileType(Type);
5307        break;
5308    }
5309  }
5310
5311  return Type;
5312}
5313
5314/// GetBuiltinType - Return the type for the specified builtin.
5315QualType ASTContext::GetBuiltinType(unsigned id,
5316                                    GetBuiltinTypeError &Error) {
5317  const char *TypeStr = BuiltinInfo.GetTypeString(id);
5318
5319  llvm::SmallVector<QualType, 8> ArgTypes;
5320
5321  Error = GE_None;
5322  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error);
5323  if (Error != GE_None)
5324    return QualType();
5325  while (TypeStr[0] && TypeStr[0] != '.') {
5326    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error);
5327    if (Error != GE_None)
5328      return QualType();
5329
5330    // Do array -> pointer decay.  The builtin should use the decayed type.
5331    if (Ty->isArrayType())
5332      Ty = getArrayDecayedType(Ty);
5333
5334    ArgTypes.push_back(Ty);
5335  }
5336
5337  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
5338         "'.' should only occur at end of builtin type list!");
5339
5340  // handle untyped/variadic arguments "T c99Style();" or "T cppStyle(...);".
5341  if (ArgTypes.size() == 0 && TypeStr[0] == '.')
5342    return getFunctionNoProtoType(ResType);
5343
5344  // FIXME: Should we create noreturn types?
5345  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(),
5346                         TypeStr[0] == '.', 0, false, false, 0, 0,
5347                         FunctionType::ExtInfo());
5348}
5349
5350QualType
5351ASTContext::UsualArithmeticConversionsType(QualType lhs, QualType rhs) {
5352  // Perform the usual unary conversions. We do this early so that
5353  // integral promotions to "int" can allow us to exit early, in the
5354  // lhs == rhs check. Also, for conversion purposes, we ignore any
5355  // qualifiers.  For example, "const float" and "float" are
5356  // equivalent.
5357  if (lhs->isPromotableIntegerType())
5358    lhs = getPromotedIntegerType(lhs);
5359  else
5360    lhs = lhs.getUnqualifiedType();
5361  if (rhs->isPromotableIntegerType())
5362    rhs = getPromotedIntegerType(rhs);
5363  else
5364    rhs = rhs.getUnqualifiedType();
5365
5366  // If both types are identical, no conversion is needed.
5367  if (lhs == rhs)
5368    return lhs;
5369
5370  // If either side is a non-arithmetic type (e.g. a pointer), we are done.
5371  // The caller can deal with this (e.g. pointer + int).
5372  if (!lhs->isArithmeticType() || !rhs->isArithmeticType())
5373    return lhs;
5374
5375  // At this point, we have two different arithmetic types.
5376
5377  // Handle complex types first (C99 6.3.1.8p1).
5378  if (lhs->isComplexType() || rhs->isComplexType()) {
5379    // if we have an integer operand, the result is the complex type.
5380    if (rhs->isIntegerType() || rhs->isComplexIntegerType()) {
5381      // convert the rhs to the lhs complex type.
5382      return lhs;
5383    }
5384    if (lhs->isIntegerType() || lhs->isComplexIntegerType()) {
5385      // convert the lhs to the rhs complex type.
5386      return rhs;
5387    }
5388    // This handles complex/complex, complex/float, or float/complex.
5389    // When both operands are complex, the shorter operand is converted to the
5390    // type of the longer, and that is the type of the result. This corresponds
5391    // to what is done when combining two real floating-point operands.
5392    // The fun begins when size promotion occur across type domains.
5393    // From H&S 6.3.4: When one operand is complex and the other is a real
5394    // floating-point type, the less precise type is converted, within it's
5395    // real or complex domain, to the precision of the other type. For example,
5396    // when combining a "long double" with a "double _Complex", the
5397    // "double _Complex" is promoted to "long double _Complex".
5398    int result = getFloatingTypeOrder(lhs, rhs);
5399
5400    if (result > 0) { // The left side is bigger, convert rhs.
5401      rhs = getFloatingTypeOfSizeWithinDomain(lhs, rhs);
5402    } else if (result < 0) { // The right side is bigger, convert lhs.
5403      lhs = getFloatingTypeOfSizeWithinDomain(rhs, lhs);
5404    }
5405    // At this point, lhs and rhs have the same rank/size. Now, make sure the
5406    // domains match. This is a requirement for our implementation, C99
5407    // does not require this promotion.
5408    if (lhs != rhs) { // Domains don't match, we have complex/float mix.
5409      if (lhs->isRealFloatingType()) { // handle "double, _Complex double".
5410        return rhs;
5411      } else { // handle "_Complex double, double".
5412        return lhs;
5413      }
5414    }
5415    return lhs; // The domain/size match exactly.
5416  }
5417  // Now handle "real" floating types (i.e. float, double, long double).
5418  if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) {
5419    // if we have an integer operand, the result is the real floating type.
5420    if (rhs->isIntegerType()) {
5421      // convert rhs to the lhs floating point type.
5422      return lhs;
5423    }
5424    if (rhs->isComplexIntegerType()) {
5425      // convert rhs to the complex floating point type.
5426      return getComplexType(lhs);
5427    }
5428    if (lhs->isIntegerType()) {
5429      // convert lhs to the rhs floating point type.
5430      return rhs;
5431    }
5432    if (lhs->isComplexIntegerType()) {
5433      // convert lhs to the complex floating point type.
5434      return getComplexType(rhs);
5435    }
5436    // We have two real floating types, float/complex combos were handled above.
5437    // Convert the smaller operand to the bigger result.
5438    int result = getFloatingTypeOrder(lhs, rhs);
5439    if (result > 0) // convert the rhs
5440      return lhs;
5441    assert(result < 0 && "illegal float comparison");
5442    return rhs;   // convert the lhs
5443  }
5444  if (lhs->isComplexIntegerType() || rhs->isComplexIntegerType()) {
5445    // Handle GCC complex int extension.
5446    const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType();
5447    const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType();
5448
5449    if (lhsComplexInt && rhsComplexInt) {
5450      if (getIntegerTypeOrder(lhsComplexInt->getElementType(),
5451                              rhsComplexInt->getElementType()) >= 0)
5452        return lhs; // convert the rhs
5453      return rhs;
5454    } else if (lhsComplexInt && rhs->isIntegerType()) {
5455      // convert the rhs to the lhs complex type.
5456      return lhs;
5457    } else if (rhsComplexInt && lhs->isIntegerType()) {
5458      // convert the lhs to the rhs complex type.
5459      return rhs;
5460    }
5461  }
5462  // Finally, we have two differing integer types.
5463  // The rules for this case are in C99 6.3.1.8
5464  int compare = getIntegerTypeOrder(lhs, rhs);
5465  bool lhsSigned = lhs->hasSignedIntegerRepresentation(),
5466       rhsSigned = rhs->hasSignedIntegerRepresentation();
5467  QualType destType;
5468  if (lhsSigned == rhsSigned) {
5469    // Same signedness; use the higher-ranked type
5470    destType = compare >= 0 ? lhs : rhs;
5471  } else if (compare != (lhsSigned ? 1 : -1)) {
5472    // The unsigned type has greater than or equal rank to the
5473    // signed type, so use the unsigned type
5474    destType = lhsSigned ? rhs : lhs;
5475  } else if (getIntWidth(lhs) != getIntWidth(rhs)) {
5476    // The two types are different widths; if we are here, that
5477    // means the signed type is larger than the unsigned type, so
5478    // use the signed type.
5479    destType = lhsSigned ? lhs : rhs;
5480  } else {
5481    // The signed type is higher-ranked than the unsigned type,
5482    // but isn't actually any bigger (like unsigned int and long
5483    // on most 32-bit systems).  Use the unsigned type corresponding
5484    // to the signed type.
5485    destType = getCorrespondingUnsignedType(lhsSigned ? lhs : rhs);
5486  }
5487  return destType;
5488}
5489
5490GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
5491  GVALinkage External = GVA_StrongExternal;
5492
5493  Linkage L = FD->getLinkage();
5494  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5495      FD->getType()->getLinkage() == UniqueExternalLinkage)
5496    L = UniqueExternalLinkage;
5497
5498  switch (L) {
5499  case NoLinkage:
5500  case InternalLinkage:
5501  case UniqueExternalLinkage:
5502    return GVA_Internal;
5503
5504  case ExternalLinkage:
5505    switch (FD->getTemplateSpecializationKind()) {
5506    case TSK_Undeclared:
5507    case TSK_ExplicitSpecialization:
5508      External = GVA_StrongExternal;
5509      break;
5510
5511    case TSK_ExplicitInstantiationDefinition:
5512      return GVA_ExplicitTemplateInstantiation;
5513
5514    case TSK_ExplicitInstantiationDeclaration:
5515    case TSK_ImplicitInstantiation:
5516      External = GVA_TemplateInstantiation;
5517      break;
5518    }
5519  }
5520
5521  if (!FD->isInlined())
5522    return External;
5523
5524  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
5525    // GNU or C99 inline semantics. Determine whether this symbol should be
5526    // externally visible.
5527    if (FD->isInlineDefinitionExternallyVisible())
5528      return External;
5529
5530    // C99 inline semantics, where the symbol is not externally visible.
5531    return GVA_C99Inline;
5532  }
5533
5534  // C++0x [temp.explicit]p9:
5535  //   [ Note: The intent is that an inline function that is the subject of
5536  //   an explicit instantiation declaration will still be implicitly
5537  //   instantiated when used so that the body can be considered for
5538  //   inlining, but that no out-of-line copy of the inline function would be
5539  //   generated in the translation unit. -- end note ]
5540  if (FD->getTemplateSpecializationKind()
5541                                       == TSK_ExplicitInstantiationDeclaration)
5542    return GVA_C99Inline;
5543
5544  return GVA_CXXInline;
5545}
5546
5547GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
5548  // If this is a static data member, compute the kind of template
5549  // specialization. Otherwise, this variable is not part of a
5550  // template.
5551  TemplateSpecializationKind TSK = TSK_Undeclared;
5552  if (VD->isStaticDataMember())
5553    TSK = VD->getTemplateSpecializationKind();
5554
5555  Linkage L = VD->getLinkage();
5556  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5557      VD->getType()->getLinkage() == UniqueExternalLinkage)
5558    L = UniqueExternalLinkage;
5559
5560  switch (L) {
5561  case NoLinkage:
5562  case InternalLinkage:
5563  case UniqueExternalLinkage:
5564    return GVA_Internal;
5565
5566  case ExternalLinkage:
5567    switch (TSK) {
5568    case TSK_Undeclared:
5569    case TSK_ExplicitSpecialization:
5570      return GVA_StrongExternal;
5571
5572    case TSK_ExplicitInstantiationDeclaration:
5573      llvm_unreachable("Variable should not be instantiated");
5574      // Fall through to treat this like any other instantiation.
5575
5576    case TSK_ExplicitInstantiationDefinition:
5577      return GVA_ExplicitTemplateInstantiation;
5578
5579    case TSK_ImplicitInstantiation:
5580      return GVA_TemplateInstantiation;
5581    }
5582  }
5583
5584  return GVA_StrongExternal;
5585}
5586
5587bool ASTContext::DeclMustBeEmitted(const Decl *D) {
5588  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
5589    if (!VD->isFileVarDecl())
5590      return false;
5591  } else if (!isa<FunctionDecl>(D))
5592    return false;
5593
5594  // Weak references don't produce any output by themselves.
5595  if (D->hasAttr<WeakRefAttr>())
5596    return false;
5597
5598  // Aliases and used decls are required.
5599  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
5600    return true;
5601
5602  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
5603    // Forward declarations aren't required.
5604    if (!FD->isThisDeclarationADefinition())
5605      return false;
5606
5607    // Constructors and destructors are required.
5608    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
5609      return true;
5610
5611    // The key function for a class is required.
5612    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
5613      const CXXRecordDecl *RD = MD->getParent();
5614      if (MD->isOutOfLine() && RD->isDynamicClass()) {
5615        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
5616        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
5617          return true;
5618      }
5619    }
5620
5621    GVALinkage Linkage = GetGVALinkageForFunction(FD);
5622
5623    // static, static inline, always_inline, and extern inline functions can
5624    // always be deferred.  Normal inline functions can be deferred in C99/C++.
5625    // Implicit template instantiations can also be deferred in C++.
5626    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
5627        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
5628      return false;
5629    return true;
5630  }
5631
5632  const VarDecl *VD = cast<VarDecl>(D);
5633  assert(VD->isFileVarDecl() && "Expected file scoped var");
5634
5635  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
5636    return false;
5637
5638  // Structs that have non-trivial constructors or destructors are required.
5639
5640  // FIXME: Handle references.
5641  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
5642    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
5643      if (RD->hasDefinition() &&
5644          (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()))
5645        return true;
5646    }
5647  }
5648
5649  GVALinkage L = GetGVALinkageForVariable(VD);
5650  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
5651    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
5652      return false;
5653  }
5654
5655  return true;
5656}
5657