ASTContext.cpp revision 74c730ad1f6818b676b0bad46d806a9176950328 
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
2215QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
2216                                          const ObjCInterfaceDecl *PrevDecl) {
2217  assert(Decl && "Passed null for Decl param");
2218
2219  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2220
2221  if (PrevDecl) {
2222    assert(PrevDecl->TypeForDecl && "previous decl has no TypeForDecl");
2223    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2224    return QualType(PrevDecl->TypeForDecl, 0);
2225  }
2226
2227  assert(!Decl->getPreviousDeclaration() &&
2228         "interface has previous declaration");
2229
2230  Decl->TypeForDecl = new (*this, TypeAlignment) ObjCInterfaceType(Decl);
2231  Types.push_back(Decl->TypeForDecl);
2232  return QualType(Decl->TypeForDecl, 0);
2233}
2234
2235/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2236/// TypeOfExprType AST's (since expression's are never shared). For example,
2237/// multiple declarations that refer to "typeof(x)" all contain different
2238/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2239/// on canonical type's (which are always unique).
2240QualType ASTContext::getTypeOfExprType(Expr *tofExpr) {
2241  TypeOfExprType *toe;
2242  if (tofExpr->isTypeDependent()) {
2243    llvm::FoldingSetNodeID ID;
2244    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2245
2246    void *InsertPos = 0;
2247    DependentTypeOfExprType *Canon
2248      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2249    if (Canon) {
2250      // We already have a "canonical" version of an identical, dependent
2251      // typeof(expr) type. Use that as our canonical type.
2252      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2253                                          QualType((TypeOfExprType*)Canon, 0));
2254    }
2255    else {
2256      // Build a new, canonical typeof(expr) type.
2257      Canon
2258        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2259      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2260      toe = Canon;
2261    }
2262  } else {
2263    QualType Canonical = getCanonicalType(tofExpr->getType());
2264    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2265  }
2266  Types.push_back(toe);
2267  return QualType(toe, 0);
2268}
2269
2270/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2271/// TypeOfType AST's. The only motivation to unique these nodes would be
2272/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2273/// an issue. This doesn't effect the type checker, since it operates
2274/// on canonical type's (which are always unique).
2275QualType ASTContext::getTypeOfType(QualType tofType) {
2276  QualType Canonical = getCanonicalType(tofType);
2277  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2278  Types.push_back(tot);
2279  return QualType(tot, 0);
2280}
2281
2282/// getDecltypeForExpr - Given an expr, will return the decltype for that
2283/// expression, according to the rules in C++0x [dcl.type.simple]p4
2284static QualType getDecltypeForExpr(const Expr *e, ASTContext &Context) {
2285  if (e->isTypeDependent())
2286    return Context.DependentTy;
2287
2288  // If e is an id expression or a class member access, decltype(e) is defined
2289  // as the type of the entity named by e.
2290  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2291    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2292      return VD->getType();
2293  }
2294  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2295    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2296      return FD->getType();
2297  }
2298  // If e is a function call or an invocation of an overloaded operator,
2299  // (parentheses around e are ignored), decltype(e) is defined as the
2300  // return type of that function.
2301  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2302    return CE->getCallReturnType();
2303
2304  QualType T = e->getType();
2305
2306  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2307  // defined as T&, otherwise decltype(e) is defined as T.
2308  if (e->isLvalue(Context) == Expr::LV_Valid)
2309    T = Context.getLValueReferenceType(T);
2310
2311  return T;
2312}
2313
2314/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2315/// DecltypeType AST's. The only motivation to unique these nodes would be
2316/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2317/// an issue. This doesn't effect the type checker, since it operates
2318/// on canonical type's (which are always unique).
2319QualType ASTContext::getDecltypeType(Expr *e) {
2320  DecltypeType *dt;
2321  if (e->isTypeDependent()) {
2322    llvm::FoldingSetNodeID ID;
2323    DependentDecltypeType::Profile(ID, *this, e);
2324
2325    void *InsertPos = 0;
2326    DependentDecltypeType *Canon
2327      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2328    if (Canon) {
2329      // We already have a "canonical" version of an equivalent, dependent
2330      // decltype type. Use that as our canonical type.
2331      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2332                                       QualType((DecltypeType*)Canon, 0));
2333    }
2334    else {
2335      // Build a new, canonical typeof(expr) type.
2336      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2337      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2338      dt = Canon;
2339    }
2340  } else {
2341    QualType T = getDecltypeForExpr(e, *this);
2342    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2343  }
2344  Types.push_back(dt);
2345  return QualType(dt, 0);
2346}
2347
2348/// getTagDeclType - Return the unique reference to the type for the
2349/// specified TagDecl (struct/union/class/enum) decl.
2350QualType ASTContext::getTagDeclType(const TagDecl *Decl) {
2351  assert (Decl);
2352  // FIXME: What is the design on getTagDeclType when it requires casting
2353  // away const?  mutable?
2354  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2355}
2356
2357/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2358/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2359/// needs to agree with the definition in <stddef.h>.
2360CanQualType ASTContext::getSizeType() const {
2361  return getFromTargetType(Target.getSizeType());
2362}
2363
2364/// getSignedWCharType - Return the type of "signed wchar_t".
2365/// Used when in C++, as a GCC extension.
2366QualType ASTContext::getSignedWCharType() const {
2367  // FIXME: derive from "Target" ?
2368  return WCharTy;
2369}
2370
2371/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
2372/// Used when in C++, as a GCC extension.
2373QualType ASTContext::getUnsignedWCharType() const {
2374  // FIXME: derive from "Target" ?
2375  return UnsignedIntTy;
2376}
2377
2378/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
2379/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
2380QualType ASTContext::getPointerDiffType() const {
2381  return getFromTargetType(Target.getPtrDiffType(0));
2382}
2383
2384//===----------------------------------------------------------------------===//
2385//                              Type Operators
2386//===----------------------------------------------------------------------===//
2387
2388CanQualType ASTContext::getCanonicalParamType(QualType T) {
2389  // Push qualifiers into arrays, and then discard any remaining
2390  // qualifiers.
2391  T = getCanonicalType(T);
2392  const Type *Ty = T.getTypePtr();
2393
2394  QualType Result;
2395  if (isa<ArrayType>(Ty)) {
2396    Result = getArrayDecayedType(QualType(Ty,0));
2397  } else if (isa<FunctionType>(Ty)) {
2398    Result = getPointerType(QualType(Ty, 0));
2399  } else {
2400    Result = QualType(Ty, 0);
2401  }
2402
2403  return CanQualType::CreateUnsafe(Result);
2404}
2405
2406/// getCanonicalType - Return the canonical (structural) type corresponding to
2407/// the specified potentially non-canonical type.  The non-canonical version
2408/// of a type may have many "decorated" versions of types.  Decorators can
2409/// include typedefs, 'typeof' operators, etc. The returned type is guaranteed
2410/// to be free of any of these, allowing two canonical types to be compared
2411/// for exact equality with a simple pointer comparison.
2412CanQualType ASTContext::getCanonicalType(QualType T) {
2413  QualifierCollector Quals;
2414  const Type *Ptr = Quals.strip(T);
2415  QualType CanType = Ptr->getCanonicalTypeInternal();
2416
2417  // The canonical internal type will be the canonical type *except*
2418  // that we push type qualifiers down through array types.
2419
2420  // If there are no new qualifiers to push down, stop here.
2421  if (!Quals.hasQualifiers())
2422    return CanQualType::CreateUnsafe(CanType);
2423
2424  // If the type qualifiers are on an array type, get the canonical
2425  // type of the array with the qualifiers applied to the element
2426  // type.
2427  ArrayType *AT = dyn_cast<ArrayType>(CanType);
2428  if (!AT)
2429    return CanQualType::CreateUnsafe(getQualifiedType(CanType, Quals));
2430
2431  // Get the canonical version of the element with the extra qualifiers on it.
2432  // This can recursively sink qualifiers through multiple levels of arrays.
2433  QualType NewEltTy = getQualifiedType(AT->getElementType(), Quals);
2434  NewEltTy = getCanonicalType(NewEltTy);
2435
2436  if (ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
2437    return CanQualType::CreateUnsafe(
2438             getConstantArrayType(NewEltTy, CAT->getSize(),
2439                                  CAT->getSizeModifier(),
2440                                  CAT->getIndexTypeCVRQualifiers()));
2441  if (IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT))
2442    return CanQualType::CreateUnsafe(
2443             getIncompleteArrayType(NewEltTy, IAT->getSizeModifier(),
2444                                    IAT->getIndexTypeCVRQualifiers()));
2445
2446  if (DependentSizedArrayType *DSAT = dyn_cast<DependentSizedArrayType>(AT))
2447    return CanQualType::CreateUnsafe(
2448             getDependentSizedArrayType(NewEltTy,
2449                                        DSAT->getSizeExpr() ?
2450                                          DSAT->getSizeExpr()->Retain() : 0,
2451                                        DSAT->getSizeModifier(),
2452                                        DSAT->getIndexTypeCVRQualifiers(),
2453                        DSAT->getBracketsRange())->getCanonicalTypeInternal());
2454
2455  VariableArrayType *VAT = cast<VariableArrayType>(AT);
2456  return CanQualType::CreateUnsafe(getVariableArrayType(NewEltTy,
2457                                                        VAT->getSizeExpr() ?
2458                                              VAT->getSizeExpr()->Retain() : 0,
2459                                                        VAT->getSizeModifier(),
2460                                              VAT->getIndexTypeCVRQualifiers(),
2461                                                     VAT->getBracketsRange()));
2462}
2463
2464QualType ASTContext::getUnqualifiedArrayType(QualType T,
2465                                             Qualifiers &Quals) {
2466  Quals = T.getQualifiers();
2467  const ArrayType *AT = getAsArrayType(T);
2468  if (!AT) {
2469    return T.getUnqualifiedType();
2470  }
2471
2472  QualType Elt = AT->getElementType();
2473  QualType UnqualElt = getUnqualifiedArrayType(Elt, Quals);
2474  if (Elt == UnqualElt)
2475    return T;
2476
2477  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
2478    return getConstantArrayType(UnqualElt, CAT->getSize(),
2479                                CAT->getSizeModifier(), 0);
2480  }
2481
2482  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
2483    return getIncompleteArrayType(UnqualElt, IAT->getSizeModifier(), 0);
2484  }
2485
2486  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
2487    return getVariableArrayType(UnqualElt,
2488                                VAT->getSizeExpr() ?
2489                                VAT->getSizeExpr()->Retain() : 0,
2490                                VAT->getSizeModifier(),
2491                                VAT->getIndexTypeCVRQualifiers(),
2492                                VAT->getBracketsRange());
2493  }
2494
2495  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
2496  return getDependentSizedArrayType(UnqualElt, DSAT->getSizeExpr()->Retain(),
2497                                    DSAT->getSizeModifier(), 0,
2498                                    SourceRange());
2499}
2500
2501/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
2502/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
2503/// they point to and return true. If T1 and T2 aren't pointer types
2504/// or pointer-to-member types, or if they are not similar at this
2505/// level, returns false and leaves T1 and T2 unchanged. Top-level
2506/// qualifiers on T1 and T2 are ignored. This function will typically
2507/// be called in a loop that successively "unwraps" pointer and
2508/// pointer-to-member types to compare them at each level.
2509bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
2510  const PointerType *T1PtrType = T1->getAs<PointerType>(),
2511                    *T2PtrType = T2->getAs<PointerType>();
2512  if (T1PtrType && T2PtrType) {
2513    T1 = T1PtrType->getPointeeType();
2514    T2 = T2PtrType->getPointeeType();
2515    return true;
2516  }
2517
2518  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
2519                          *T2MPType = T2->getAs<MemberPointerType>();
2520  if (T1MPType && T2MPType &&
2521      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
2522                             QualType(T2MPType->getClass(), 0))) {
2523    T1 = T1MPType->getPointeeType();
2524    T2 = T2MPType->getPointeeType();
2525    return true;
2526  }
2527
2528  if (getLangOptions().ObjC1) {
2529    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
2530                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
2531    if (T1OPType && T2OPType) {
2532      T1 = T1OPType->getPointeeType();
2533      T2 = T2OPType->getPointeeType();
2534      return true;
2535    }
2536  }
2537
2538  // FIXME: Block pointers, too?
2539
2540  return false;
2541}
2542
2543DeclarationName ASTContext::getNameForTemplate(TemplateName Name) {
2544  if (TemplateDecl *TD = Name.getAsTemplateDecl())
2545    return TD->getDeclName();
2546
2547  if (DependentTemplateName *DTN = Name.getAsDependentTemplateName()) {
2548    if (DTN->isIdentifier()) {
2549      return DeclarationNames.getIdentifier(DTN->getIdentifier());
2550    } else {
2551      return DeclarationNames.getCXXOperatorName(DTN->getOperator());
2552    }
2553  }
2554
2555  OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
2556  assert(Storage);
2557  return (*Storage->begin())->getDeclName();
2558}
2559
2560TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) {
2561  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
2562    if (TemplateTemplateParmDecl *TTP
2563                              = dyn_cast<TemplateTemplateParmDecl>(Template))
2564      Template = getCanonicalTemplateTemplateParmDecl(TTP);
2565
2566    // The canonical template name is the canonical template declaration.
2567    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
2568  }
2569
2570  assert(!Name.getAsOverloadedTemplate());
2571
2572  DependentTemplateName *DTN = Name.getAsDependentTemplateName();
2573  assert(DTN && "Non-dependent template names must refer to template decls.");
2574  return DTN->CanonicalTemplateName;
2575}
2576
2577bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
2578  X = getCanonicalTemplateName(X);
2579  Y = getCanonicalTemplateName(Y);
2580  return X.getAsVoidPointer() == Y.getAsVoidPointer();
2581}
2582
2583TemplateArgument
2584ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) {
2585  switch (Arg.getKind()) {
2586    case TemplateArgument::Null:
2587      return Arg;
2588
2589    case TemplateArgument::Expression:
2590      return Arg;
2591
2592    case TemplateArgument::Declaration:
2593      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
2594
2595    case TemplateArgument::Template:
2596      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
2597
2598    case TemplateArgument::Integral:
2599      return TemplateArgument(*Arg.getAsIntegral(),
2600                              getCanonicalType(Arg.getIntegralType()));
2601
2602    case TemplateArgument::Type:
2603      return TemplateArgument(getCanonicalType(Arg.getAsType()));
2604
2605    case TemplateArgument::Pack: {
2606      // FIXME: Allocate in ASTContext
2607      TemplateArgument *CanonArgs = new TemplateArgument[Arg.pack_size()];
2608      unsigned Idx = 0;
2609      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
2610                                        AEnd = Arg.pack_end();
2611           A != AEnd; (void)++A, ++Idx)
2612        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
2613
2614      TemplateArgument Result;
2615      Result.setArgumentPack(CanonArgs, Arg.pack_size(), false);
2616      return Result;
2617    }
2618  }
2619
2620  // Silence GCC warning
2621  assert(false && "Unhandled template argument kind");
2622  return TemplateArgument();
2623}
2624
2625NestedNameSpecifier *
2626ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) {
2627  if (!NNS)
2628    return 0;
2629
2630  switch (NNS->getKind()) {
2631  case NestedNameSpecifier::Identifier:
2632    // Canonicalize the prefix but keep the identifier the same.
2633    return NestedNameSpecifier::Create(*this,
2634                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
2635                                       NNS->getAsIdentifier());
2636
2637  case NestedNameSpecifier::Namespace:
2638    // A namespace is canonical; build a nested-name-specifier with
2639    // this namespace and no prefix.
2640    return NestedNameSpecifier::Create(*this, 0, NNS->getAsNamespace());
2641
2642  case NestedNameSpecifier::TypeSpec:
2643  case NestedNameSpecifier::TypeSpecWithTemplate: {
2644    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
2645    return NestedNameSpecifier::Create(*this, 0,
2646                 NNS->getKind() == NestedNameSpecifier::TypeSpecWithTemplate,
2647                                       T.getTypePtr());
2648  }
2649
2650  case NestedNameSpecifier::Global:
2651    // The global specifier is canonical and unique.
2652    return NNS;
2653  }
2654
2655  // Required to silence a GCC warning
2656  return 0;
2657}
2658
2659
2660const ArrayType *ASTContext::getAsArrayType(QualType T) {
2661  // Handle the non-qualified case efficiently.
2662  if (!T.hasLocalQualifiers()) {
2663    // Handle the common positive case fast.
2664    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
2665      return AT;
2666  }
2667
2668  // Handle the common negative case fast.
2669  QualType CType = T->getCanonicalTypeInternal();
2670  if (!isa<ArrayType>(CType))
2671    return 0;
2672
2673  // Apply any qualifiers from the array type to the element type.  This
2674  // implements C99 6.7.3p8: "If the specification of an array type includes
2675  // any type qualifiers, the element type is so qualified, not the array type."
2676
2677  // If we get here, we either have type qualifiers on the type, or we have
2678  // sugar such as a typedef in the way.  If we have type qualifiers on the type
2679  // we must propagate them down into the element type.
2680
2681  QualifierCollector Qs;
2682  const Type *Ty = Qs.strip(T.getDesugaredType());
2683
2684  // If we have a simple case, just return now.
2685  const ArrayType *ATy = dyn_cast<ArrayType>(Ty);
2686  if (ATy == 0 || Qs.empty())
2687    return ATy;
2688
2689  // Otherwise, we have an array and we have qualifiers on it.  Push the
2690  // qualifiers into the array element type and return a new array type.
2691  // Get the canonical version of the element with the extra qualifiers on it.
2692  // This can recursively sink qualifiers through multiple levels of arrays.
2693  QualType NewEltTy = getQualifiedType(ATy->getElementType(), Qs);
2694
2695  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
2696    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
2697                                                CAT->getSizeModifier(),
2698                                           CAT->getIndexTypeCVRQualifiers()));
2699  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
2700    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
2701                                                  IAT->getSizeModifier(),
2702                                           IAT->getIndexTypeCVRQualifiers()));
2703
2704  if (const DependentSizedArrayType *DSAT
2705        = dyn_cast<DependentSizedArrayType>(ATy))
2706    return cast<ArrayType>(
2707                     getDependentSizedArrayType(NewEltTy,
2708                                                DSAT->getSizeExpr() ?
2709                                              DSAT->getSizeExpr()->Retain() : 0,
2710                                                DSAT->getSizeModifier(),
2711                                              DSAT->getIndexTypeCVRQualifiers(),
2712                                                DSAT->getBracketsRange()));
2713
2714  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
2715  return cast<ArrayType>(getVariableArrayType(NewEltTy,
2716                                              VAT->getSizeExpr() ?
2717                                              VAT->getSizeExpr()->Retain() : 0,
2718                                              VAT->getSizeModifier(),
2719                                              VAT->getIndexTypeCVRQualifiers(),
2720                                              VAT->getBracketsRange()));
2721}
2722
2723
2724/// getArrayDecayedType - Return the properly qualified result of decaying the
2725/// specified array type to a pointer.  This operation is non-trivial when
2726/// handling typedefs etc.  The canonical type of "T" must be an array type,
2727/// this returns a pointer to a properly qualified element of the array.
2728///
2729/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
2730QualType ASTContext::getArrayDecayedType(QualType Ty) {
2731  // Get the element type with 'getAsArrayType' so that we don't lose any
2732  // typedefs in the element type of the array.  This also handles propagation
2733  // of type qualifiers from the array type into the element type if present
2734  // (C99 6.7.3p8).
2735  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
2736  assert(PrettyArrayType && "Not an array type!");
2737
2738  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
2739
2740  // int x[restrict 4] ->  int *restrict
2741  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
2742}
2743
2744QualType ASTContext::getBaseElementType(QualType QT) {
2745  QualifierCollector Qs;
2746  while (const ArrayType *AT = getAsArrayType(QualType(Qs.strip(QT), 0)))
2747    QT = AT->getElementType();
2748  return Qs.apply(QT);
2749}
2750
2751QualType ASTContext::getBaseElementType(const ArrayType *AT) {
2752  QualType ElemTy = AT->getElementType();
2753
2754  if (const ArrayType *AT = getAsArrayType(ElemTy))
2755    return getBaseElementType(AT);
2756
2757  return ElemTy;
2758}
2759
2760/// getConstantArrayElementCount - Returns number of constant array elements.
2761uint64_t
2762ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
2763  uint64_t ElementCount = 1;
2764  do {
2765    ElementCount *= CA->getSize().getZExtValue();
2766    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
2767  } while (CA);
2768  return ElementCount;
2769}
2770
2771/// getFloatingRank - Return a relative rank for floating point types.
2772/// This routine will assert if passed a built-in type that isn't a float.
2773static FloatingRank getFloatingRank(QualType T) {
2774  if (const ComplexType *CT = T->getAs<ComplexType>())
2775    return getFloatingRank(CT->getElementType());
2776
2777  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
2778  switch (T->getAs<BuiltinType>()->getKind()) {
2779  default: assert(0 && "getFloatingRank(): not a floating type");
2780  case BuiltinType::Float:      return FloatRank;
2781  case BuiltinType::Double:     return DoubleRank;
2782  case BuiltinType::LongDouble: return LongDoubleRank;
2783  }
2784}
2785
2786/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
2787/// point or a complex type (based on typeDomain/typeSize).
2788/// 'typeDomain' is a real floating point or complex type.
2789/// 'typeSize' is a real floating point or complex type.
2790QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
2791                                                       QualType Domain) const {
2792  FloatingRank EltRank = getFloatingRank(Size);
2793  if (Domain->isComplexType()) {
2794    switch (EltRank) {
2795    default: assert(0 && "getFloatingRank(): illegal value for rank");
2796    case FloatRank:      return FloatComplexTy;
2797    case DoubleRank:     return DoubleComplexTy;
2798    case LongDoubleRank: return LongDoubleComplexTy;
2799    }
2800  }
2801
2802  assert(Domain->isRealFloatingType() && "Unknown domain!");
2803  switch (EltRank) {
2804  default: assert(0 && "getFloatingRank(): illegal value for rank");
2805  case FloatRank:      return FloatTy;
2806  case DoubleRank:     return DoubleTy;
2807  case LongDoubleRank: return LongDoubleTy;
2808  }
2809}
2810
2811/// getFloatingTypeOrder - Compare the rank of the two specified floating
2812/// point types, ignoring the domain of the type (i.e. 'double' ==
2813/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2814/// LHS < RHS, return -1.
2815int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) {
2816  FloatingRank LHSR = getFloatingRank(LHS);
2817  FloatingRank RHSR = getFloatingRank(RHS);
2818
2819  if (LHSR == RHSR)
2820    return 0;
2821  if (LHSR > RHSR)
2822    return 1;
2823  return -1;
2824}
2825
2826/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
2827/// routine will assert if passed a built-in type that isn't an integer or enum,
2828/// or if it is not canonicalized.
2829unsigned ASTContext::getIntegerRank(Type *T) {
2830  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
2831  if (EnumType* ET = dyn_cast<EnumType>(T))
2832    T = ET->getDecl()->getPromotionType().getTypePtr();
2833
2834  if (T->isSpecificBuiltinType(BuiltinType::WChar))
2835    T = getFromTargetType(Target.getWCharType()).getTypePtr();
2836
2837  if (T->isSpecificBuiltinType(BuiltinType::Char16))
2838    T = getFromTargetType(Target.getChar16Type()).getTypePtr();
2839
2840  if (T->isSpecificBuiltinType(BuiltinType::Char32))
2841    T = getFromTargetType(Target.getChar32Type()).getTypePtr();
2842
2843  switch (cast<BuiltinType>(T)->getKind()) {
2844  default: assert(0 && "getIntegerRank(): not a built-in integer");
2845  case BuiltinType::Bool:
2846    return 1 + (getIntWidth(BoolTy) << 3);
2847  case BuiltinType::Char_S:
2848  case BuiltinType::Char_U:
2849  case BuiltinType::SChar:
2850  case BuiltinType::UChar:
2851    return 2 + (getIntWidth(CharTy) << 3);
2852  case BuiltinType::Short:
2853  case BuiltinType::UShort:
2854    return 3 + (getIntWidth(ShortTy) << 3);
2855  case BuiltinType::Int:
2856  case BuiltinType::UInt:
2857    return 4 + (getIntWidth(IntTy) << 3);
2858  case BuiltinType::Long:
2859  case BuiltinType::ULong:
2860    return 5 + (getIntWidth(LongTy) << 3);
2861  case BuiltinType::LongLong:
2862  case BuiltinType::ULongLong:
2863    return 6 + (getIntWidth(LongLongTy) << 3);
2864  case BuiltinType::Int128:
2865  case BuiltinType::UInt128:
2866    return 7 + (getIntWidth(Int128Ty) << 3);
2867  }
2868}
2869
2870/// \brief Whether this is a promotable bitfield reference according
2871/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
2872///
2873/// \returns the type this bit-field will promote to, or NULL if no
2874/// promotion occurs.
2875QualType ASTContext::isPromotableBitField(Expr *E) {
2876  if (E->isTypeDependent() || E->isValueDependent())
2877    return QualType();
2878
2879  FieldDecl *Field = E->getBitField();
2880  if (!Field)
2881    return QualType();
2882
2883  QualType FT = Field->getType();
2884
2885  llvm::APSInt BitWidthAP = Field->getBitWidth()->EvaluateAsInt(*this);
2886  uint64_t BitWidth = BitWidthAP.getZExtValue();
2887  uint64_t IntSize = getTypeSize(IntTy);
2888  // GCC extension compatibility: if the bit-field size is less than or equal
2889  // to the size of int, it gets promoted no matter what its type is.
2890  // For instance, unsigned long bf : 4 gets promoted to signed int.
2891  if (BitWidth < IntSize)
2892    return IntTy;
2893
2894  if (BitWidth == IntSize)
2895    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
2896
2897  // Types bigger than int are not subject to promotions, and therefore act
2898  // like the base type.
2899  // FIXME: This doesn't quite match what gcc does, but what gcc does here
2900  // is ridiculous.
2901  return QualType();
2902}
2903
2904/// getPromotedIntegerType - Returns the type that Promotable will
2905/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
2906/// integer type.
2907QualType ASTContext::getPromotedIntegerType(QualType Promotable) {
2908  assert(!Promotable.isNull());
2909  assert(Promotable->isPromotableIntegerType());
2910  if (const EnumType *ET = Promotable->getAs<EnumType>())
2911    return ET->getDecl()->getPromotionType();
2912  if (Promotable->isSignedIntegerType())
2913    return IntTy;
2914  uint64_t PromotableSize = getTypeSize(Promotable);
2915  uint64_t IntSize = getTypeSize(IntTy);
2916  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
2917  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
2918}
2919
2920/// getIntegerTypeOrder - Returns the highest ranked integer type:
2921/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2922/// LHS < RHS, return -1.
2923int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) {
2924  Type *LHSC = getCanonicalType(LHS).getTypePtr();
2925  Type *RHSC = getCanonicalType(RHS).getTypePtr();
2926  if (LHSC == RHSC) return 0;
2927
2928  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
2929  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
2930
2931  unsigned LHSRank = getIntegerRank(LHSC);
2932  unsigned RHSRank = getIntegerRank(RHSC);
2933
2934  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
2935    if (LHSRank == RHSRank) return 0;
2936    return LHSRank > RHSRank ? 1 : -1;
2937  }
2938
2939  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
2940  if (LHSUnsigned) {
2941    // If the unsigned [LHS] type is larger, return it.
2942    if (LHSRank >= RHSRank)
2943      return 1;
2944
2945    // If the signed type can represent all values of the unsigned type, it
2946    // wins.  Because we are dealing with 2's complement and types that are
2947    // powers of two larger than each other, this is always safe.
2948    return -1;
2949  }
2950
2951  // If the unsigned [RHS] type is larger, return it.
2952  if (RHSRank >= LHSRank)
2953    return -1;
2954
2955  // If the signed type can represent all values of the unsigned type, it
2956  // wins.  Because we are dealing with 2's complement and types that are
2957  // powers of two larger than each other, this is always safe.
2958  return 1;
2959}
2960
2961static RecordDecl *
2962CreateRecordDecl(ASTContext &Ctx, RecordDecl::TagKind TK, DeclContext *DC,
2963                 SourceLocation L, IdentifierInfo *Id) {
2964  if (Ctx.getLangOptions().CPlusPlus)
2965    return CXXRecordDecl::Create(Ctx, TK, DC, L, Id);
2966  else
2967    return RecordDecl::Create(Ctx, TK, DC, L, Id);
2968}
2969
2970// getCFConstantStringType - Return the type used for constant CFStrings.
2971QualType ASTContext::getCFConstantStringType() {
2972  if (!CFConstantStringTypeDecl) {
2973    CFConstantStringTypeDecl =
2974      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
2975                       &Idents.get("NSConstantString"));
2976    CFConstantStringTypeDecl->startDefinition();
2977
2978    QualType FieldTypes[4];
2979
2980    // const int *isa;
2981    FieldTypes[0] = getPointerType(IntTy.withConst());
2982    // int flags;
2983    FieldTypes[1] = IntTy;
2984    // const char *str;
2985    FieldTypes[2] = getPointerType(CharTy.withConst());
2986    // long length;
2987    FieldTypes[3] = LongTy;
2988
2989    // Create fields
2990    for (unsigned i = 0; i < 4; ++i) {
2991      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
2992                                           SourceLocation(), 0,
2993                                           FieldTypes[i], /*TInfo=*/0,
2994                                           /*BitWidth=*/0,
2995                                           /*Mutable=*/false);
2996      Field->setAccess(AS_public);
2997      CFConstantStringTypeDecl->addDecl(Field);
2998    }
2999
3000    CFConstantStringTypeDecl->completeDefinition();
3001  }
3002
3003  return getTagDeclType(CFConstantStringTypeDecl);
3004}
3005
3006void ASTContext::setCFConstantStringType(QualType T) {
3007  const RecordType *Rec = T->getAs<RecordType>();
3008  assert(Rec && "Invalid CFConstantStringType");
3009  CFConstantStringTypeDecl = Rec->getDecl();
3010}
3011
3012// getNSConstantStringType - Return the type used for constant NSStrings.
3013QualType ASTContext::getNSConstantStringType() {
3014  if (!NSConstantStringTypeDecl) {
3015    NSConstantStringTypeDecl =
3016    CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3017                     &Idents.get("__builtin_NSString"));
3018    NSConstantStringTypeDecl->startDefinition();
3019
3020    QualType FieldTypes[3];
3021
3022    // const int *isa;
3023    FieldTypes[0] = getPointerType(IntTy.withConst());
3024    // const char *str;
3025    FieldTypes[1] = getPointerType(CharTy.withConst());
3026    // unsigned int length;
3027    FieldTypes[2] = UnsignedIntTy;
3028
3029    // Create fields
3030    for (unsigned i = 0; i < 3; ++i) {
3031      FieldDecl *Field = FieldDecl::Create(*this, NSConstantStringTypeDecl,
3032                                           SourceLocation(), 0,
3033                                           FieldTypes[i], /*TInfo=*/0,
3034                                           /*BitWidth=*/0,
3035                                           /*Mutable=*/false);
3036      Field->setAccess(AS_public);
3037      NSConstantStringTypeDecl->addDecl(Field);
3038    }
3039
3040    NSConstantStringTypeDecl->completeDefinition();
3041  }
3042
3043  return getTagDeclType(NSConstantStringTypeDecl);
3044}
3045
3046void ASTContext::setNSConstantStringType(QualType T) {
3047  const RecordType *Rec = T->getAs<RecordType>();
3048  assert(Rec && "Invalid NSConstantStringType");
3049  NSConstantStringTypeDecl = Rec->getDecl();
3050}
3051
3052QualType ASTContext::getObjCFastEnumerationStateType() {
3053  if (!ObjCFastEnumerationStateTypeDecl) {
3054    ObjCFastEnumerationStateTypeDecl =
3055      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3056                       &Idents.get("__objcFastEnumerationState"));
3057    ObjCFastEnumerationStateTypeDecl->startDefinition();
3058
3059    QualType FieldTypes[] = {
3060      UnsignedLongTy,
3061      getPointerType(ObjCIdTypedefType),
3062      getPointerType(UnsignedLongTy),
3063      getConstantArrayType(UnsignedLongTy,
3064                           llvm::APInt(32, 5), ArrayType::Normal, 0)
3065    };
3066
3067    for (size_t i = 0; i < 4; ++i) {
3068      FieldDecl *Field = FieldDecl::Create(*this,
3069                                           ObjCFastEnumerationStateTypeDecl,
3070                                           SourceLocation(), 0,
3071                                           FieldTypes[i], /*TInfo=*/0,
3072                                           /*BitWidth=*/0,
3073                                           /*Mutable=*/false);
3074      Field->setAccess(AS_public);
3075      ObjCFastEnumerationStateTypeDecl->addDecl(Field);
3076    }
3077    if (getLangOptions().CPlusPlus)
3078      if (CXXRecordDecl *CXXRD =
3079            dyn_cast<CXXRecordDecl>(ObjCFastEnumerationStateTypeDecl))
3080        CXXRD->setEmpty(false);
3081
3082    ObjCFastEnumerationStateTypeDecl->completeDefinition();
3083  }
3084
3085  return getTagDeclType(ObjCFastEnumerationStateTypeDecl);
3086}
3087
3088QualType ASTContext::getBlockDescriptorType() {
3089  if (BlockDescriptorType)
3090    return getTagDeclType(BlockDescriptorType);
3091
3092  RecordDecl *T;
3093  // FIXME: Needs the FlagAppleBlock bit.
3094  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3095                       &Idents.get("__block_descriptor"));
3096  T->startDefinition();
3097
3098  QualType FieldTypes[] = {
3099    UnsignedLongTy,
3100    UnsignedLongTy,
3101  };
3102
3103  const char *FieldNames[] = {
3104    "reserved",
3105    "Size"
3106  };
3107
3108  for (size_t i = 0; i < 2; ++i) {
3109    FieldDecl *Field = FieldDecl::Create(*this,
3110                                         T,
3111                                         SourceLocation(),
3112                                         &Idents.get(FieldNames[i]),
3113                                         FieldTypes[i], /*TInfo=*/0,
3114                                         /*BitWidth=*/0,
3115                                         /*Mutable=*/false);
3116    Field->setAccess(AS_public);
3117    T->addDecl(Field);
3118  }
3119
3120  T->completeDefinition();
3121
3122  BlockDescriptorType = T;
3123
3124  return getTagDeclType(BlockDescriptorType);
3125}
3126
3127void ASTContext::setBlockDescriptorType(QualType T) {
3128  const RecordType *Rec = T->getAs<RecordType>();
3129  assert(Rec && "Invalid BlockDescriptorType");
3130  BlockDescriptorType = Rec->getDecl();
3131}
3132
3133QualType ASTContext::getBlockDescriptorExtendedType() {
3134  if (BlockDescriptorExtendedType)
3135    return getTagDeclType(BlockDescriptorExtendedType);
3136
3137  RecordDecl *T;
3138  // FIXME: Needs the FlagAppleBlock bit.
3139  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3140                       &Idents.get("__block_descriptor_withcopydispose"));
3141  T->startDefinition();
3142
3143  QualType FieldTypes[] = {
3144    UnsignedLongTy,
3145    UnsignedLongTy,
3146    getPointerType(VoidPtrTy),
3147    getPointerType(VoidPtrTy)
3148  };
3149
3150  const char *FieldNames[] = {
3151    "reserved",
3152    "Size",
3153    "CopyFuncPtr",
3154    "DestroyFuncPtr"
3155  };
3156
3157  for (size_t i = 0; i < 4; ++i) {
3158    FieldDecl *Field = FieldDecl::Create(*this,
3159                                         T,
3160                                         SourceLocation(),
3161                                         &Idents.get(FieldNames[i]),
3162                                         FieldTypes[i], /*TInfo=*/0,
3163                                         /*BitWidth=*/0,
3164                                         /*Mutable=*/false);
3165    Field->setAccess(AS_public);
3166    T->addDecl(Field);
3167  }
3168
3169  T->completeDefinition();
3170
3171  BlockDescriptorExtendedType = T;
3172
3173  return getTagDeclType(BlockDescriptorExtendedType);
3174}
3175
3176void ASTContext::setBlockDescriptorExtendedType(QualType T) {
3177  const RecordType *Rec = T->getAs<RecordType>();
3178  assert(Rec && "Invalid BlockDescriptorType");
3179  BlockDescriptorExtendedType = Rec->getDecl();
3180}
3181
3182bool ASTContext::BlockRequiresCopying(QualType Ty) {
3183  if (Ty->isBlockPointerType())
3184    return true;
3185  if (isObjCNSObjectType(Ty))
3186    return true;
3187  if (Ty->isObjCObjectPointerType())
3188    return true;
3189  return false;
3190}
3191
3192QualType ASTContext::BuildByRefType(const char *DeclName, QualType Ty) {
3193  //  type = struct __Block_byref_1_X {
3194  //    void *__isa;
3195  //    struct __Block_byref_1_X *__forwarding;
3196  //    unsigned int __flags;
3197  //    unsigned int __size;
3198  //    void *__copy_helper;		// as needed
3199  //    void *__destroy_help		// as needed
3200  //    int X;
3201  //  } *
3202
3203  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3204
3205  // FIXME: Move up
3206  llvm::SmallString<36> Name;
3207  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3208                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3209  RecordDecl *T;
3210  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3211                       &Idents.get(Name.str()));
3212  T->startDefinition();
3213  QualType Int32Ty = IntTy;
3214  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3215  QualType FieldTypes[] = {
3216    getPointerType(VoidPtrTy),
3217    getPointerType(getTagDeclType(T)),
3218    Int32Ty,
3219    Int32Ty,
3220    getPointerType(VoidPtrTy),
3221    getPointerType(VoidPtrTy),
3222    Ty
3223  };
3224
3225  const char *FieldNames[] = {
3226    "__isa",
3227    "__forwarding",
3228    "__flags",
3229    "__size",
3230    "__copy_helper",
3231    "__destroy_helper",
3232    DeclName,
3233  };
3234
3235  for (size_t i = 0; i < 7; ++i) {
3236    if (!HasCopyAndDispose && i >=4 && i <= 5)
3237      continue;
3238    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3239                                         &Idents.get(FieldNames[i]),
3240                                         FieldTypes[i], /*TInfo=*/0,
3241                                         /*BitWidth=*/0, /*Mutable=*/false);
3242    Field->setAccess(AS_public);
3243    T->addDecl(Field);
3244  }
3245
3246  T->completeDefinition();
3247
3248  return getPointerType(getTagDeclType(T));
3249}
3250
3251
3252QualType ASTContext::getBlockParmType(
3253  bool BlockHasCopyDispose,
3254  llvm::SmallVectorImpl<const Expr *> &Layout) {
3255
3256  // FIXME: Move up
3257  llvm::SmallString<36> Name;
3258  llvm::raw_svector_ostream(Name) << "__block_literal_"
3259                                  << ++UniqueBlockParmTypeID;
3260  RecordDecl *T;
3261  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3262                       &Idents.get(Name.str()));
3263  T->startDefinition();
3264  QualType FieldTypes[] = {
3265    getPointerType(VoidPtrTy),
3266    IntTy,
3267    IntTy,
3268    getPointerType(VoidPtrTy),
3269    (BlockHasCopyDispose ?
3270     getPointerType(getBlockDescriptorExtendedType()) :
3271     getPointerType(getBlockDescriptorType()))
3272  };
3273
3274  const char *FieldNames[] = {
3275    "__isa",
3276    "__flags",
3277    "__reserved",
3278    "__FuncPtr",
3279    "__descriptor"
3280  };
3281
3282  for (size_t i = 0; i < 5; ++i) {
3283    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3284                                         &Idents.get(FieldNames[i]),
3285                                         FieldTypes[i], /*TInfo=*/0,
3286                                         /*BitWidth=*/0, /*Mutable=*/false);
3287    Field->setAccess(AS_public);
3288    T->addDecl(Field);
3289  }
3290
3291  for (unsigned i = 0; i < Layout.size(); ++i) {
3292    const Expr *E = Layout[i];
3293
3294    QualType FieldType = E->getType();
3295    IdentifierInfo *FieldName = 0;
3296    if (isa<CXXThisExpr>(E)) {
3297      FieldName = &Idents.get("this");
3298    } else if (const BlockDeclRefExpr *BDRE = dyn_cast<BlockDeclRefExpr>(E)) {
3299      const ValueDecl *D = BDRE->getDecl();
3300      FieldName = D->getIdentifier();
3301      if (BDRE->isByRef())
3302        FieldType = BuildByRefType(D->getNameAsCString(), FieldType);
3303    } else {
3304      // Padding.
3305      assert(isa<ConstantArrayType>(FieldType) &&
3306             isa<DeclRefExpr>(E) &&
3307             !cast<DeclRefExpr>(E)->getDecl()->getDeclName() &&
3308             "doesn't match characteristics of padding decl");
3309    }
3310
3311    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3312                                         FieldName, FieldType, /*TInfo=*/0,
3313                                         /*BitWidth=*/0, /*Mutable=*/false);
3314    Field->setAccess(AS_public);
3315    T->addDecl(Field);
3316  }
3317
3318  T->completeDefinition();
3319
3320  return getPointerType(getTagDeclType(T));
3321}
3322
3323void ASTContext::setObjCFastEnumerationStateType(QualType T) {
3324  const RecordType *Rec = T->getAs<RecordType>();
3325  assert(Rec && "Invalid ObjCFAstEnumerationStateType");
3326  ObjCFastEnumerationStateTypeDecl = Rec->getDecl();
3327}
3328
3329// This returns true if a type has been typedefed to BOOL:
3330// typedef <type> BOOL;
3331static bool isTypeTypedefedAsBOOL(QualType T) {
3332  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3333    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3334      return II->isStr("BOOL");
3335
3336  return false;
3337}
3338
3339/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3340/// purpose.
3341CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) {
3342  CharUnits sz = getTypeSizeInChars(type);
3343
3344  // Make all integer and enum types at least as large as an int
3345  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3346    sz = std::max(sz, getTypeSizeInChars(IntTy));
3347  // Treat arrays as pointers, since that's how they're passed in.
3348  else if (type->isArrayType())
3349    sz = getTypeSizeInChars(VoidPtrTy);
3350  return sz;
3351}
3352
3353static inline
3354std::string charUnitsToString(const CharUnits &CU) {
3355  return llvm::itostr(CU.getQuantity());
3356}
3357
3358/// getObjCEncodingForBlockDecl - Return the encoded type for this block
3359/// declaration.
3360void ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr,
3361                                             std::string& S) {
3362  const BlockDecl *Decl = Expr->getBlockDecl();
3363  QualType BlockTy =
3364      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3365  // Encode result type.
3366  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3367  // Compute size of all parameters.
3368  // Start with computing size of a pointer in number of bytes.
3369  // FIXME: There might(should) be a better way of doing this computation!
3370  SourceLocation Loc;
3371  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3372  CharUnits ParmOffset = PtrSize;
3373  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3374       E = Decl->param_end(); PI != E; ++PI) {
3375    QualType PType = (*PI)->getType();
3376    CharUnits sz = getObjCEncodingTypeSize(PType);
3377    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3378    ParmOffset += sz;
3379  }
3380  // Size of the argument frame
3381  S += charUnitsToString(ParmOffset);
3382  // Block pointer and offset.
3383  S += "@?0";
3384  ParmOffset = PtrSize;
3385
3386  // Argument types.
3387  ParmOffset = PtrSize;
3388  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3389       Decl->param_end(); PI != E; ++PI) {
3390    ParmVarDecl *PVDecl = *PI;
3391    QualType PType = PVDecl->getOriginalType();
3392    if (const ArrayType *AT =
3393          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3394      // Use array's original type only if it has known number of
3395      // elements.
3396      if (!isa<ConstantArrayType>(AT))
3397        PType = PVDecl->getType();
3398    } else if (PType->isFunctionType())
3399      PType = PVDecl->getType();
3400    getObjCEncodingForType(PType, S);
3401    S += charUnitsToString(ParmOffset);
3402    ParmOffset += getObjCEncodingTypeSize(PType);
3403  }
3404}
3405
3406/// getObjCEncodingForMethodDecl - Return the encoded type for this method
3407/// declaration.
3408void ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
3409                                              std::string& S) {
3410  // FIXME: This is not very efficient.
3411  // Encode type qualifer, 'in', 'inout', etc. for the return type.
3412  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
3413  // Encode result type.
3414  getObjCEncodingForType(Decl->getResultType(), S);
3415  // Compute size of all parameters.
3416  // Start with computing size of a pointer in number of bytes.
3417  // FIXME: There might(should) be a better way of doing this computation!
3418  SourceLocation Loc;
3419  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3420  // The first two arguments (self and _cmd) are pointers; account for
3421  // their size.
3422  CharUnits ParmOffset = 2 * PtrSize;
3423  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3424       E = Decl->sel_param_end(); PI != E; ++PI) {
3425    QualType PType = (*PI)->getType();
3426    CharUnits sz = getObjCEncodingTypeSize(PType);
3427    assert (sz.isPositive() &&
3428        "getObjCEncodingForMethodDecl - Incomplete param type");
3429    ParmOffset += sz;
3430  }
3431  S += charUnitsToString(ParmOffset);
3432  S += "@0:";
3433  S += charUnitsToString(PtrSize);
3434
3435  // Argument types.
3436  ParmOffset = 2 * PtrSize;
3437  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3438       E = Decl->sel_param_end(); PI != E; ++PI) {
3439    ParmVarDecl *PVDecl = *PI;
3440    QualType PType = PVDecl->getOriginalType();
3441    if (const ArrayType *AT =
3442          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3443      // Use array's original type only if it has known number of
3444      // elements.
3445      if (!isa<ConstantArrayType>(AT))
3446        PType = PVDecl->getType();
3447    } else if (PType->isFunctionType())
3448      PType = PVDecl->getType();
3449    // Process argument qualifiers for user supplied arguments; such as,
3450    // 'in', 'inout', etc.
3451    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
3452    getObjCEncodingForType(PType, S);
3453    S += charUnitsToString(ParmOffset);
3454    ParmOffset += getObjCEncodingTypeSize(PType);
3455  }
3456}
3457
3458/// getObjCEncodingForPropertyDecl - Return the encoded type for this
3459/// property declaration. If non-NULL, Container must be either an
3460/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
3461/// NULL when getting encodings for protocol properties.
3462/// Property attributes are stored as a comma-delimited C string. The simple
3463/// attributes readonly and bycopy are encoded as single characters. The
3464/// parametrized attributes, getter=name, setter=name, and ivar=name, are
3465/// encoded as single characters, followed by an identifier. Property types
3466/// are also encoded as a parametrized attribute. The characters used to encode
3467/// these attributes are defined by the following enumeration:
3468/// @code
3469/// enum PropertyAttributes {
3470/// kPropertyReadOnly = 'R',   // property is read-only.
3471/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
3472/// kPropertyByref = '&',  // property is a reference to the value last assigned
3473/// kPropertyDynamic = 'D',    // property is dynamic
3474/// kPropertyGetter = 'G',     // followed by getter selector name
3475/// kPropertySetter = 'S',     // followed by setter selector name
3476/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
3477/// kPropertyType = 't'              // followed by old-style type encoding.
3478/// kPropertyWeak = 'W'              // 'weak' property
3479/// kPropertyStrong = 'P'            // property GC'able
3480/// kPropertyNonAtomic = 'N'         // property non-atomic
3481/// };
3482/// @endcode
3483void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
3484                                                const Decl *Container,
3485                                                std::string& S) {
3486  // Collect information from the property implementation decl(s).
3487  bool Dynamic = false;
3488  ObjCPropertyImplDecl *SynthesizePID = 0;
3489
3490  // FIXME: Duplicated code due to poor abstraction.
3491  if (Container) {
3492    if (const ObjCCategoryImplDecl *CID =
3493        dyn_cast<ObjCCategoryImplDecl>(Container)) {
3494      for (ObjCCategoryImplDecl::propimpl_iterator
3495             i = CID->propimpl_begin(), e = CID->propimpl_end();
3496           i != e; ++i) {
3497        ObjCPropertyImplDecl *PID = *i;
3498        if (PID->getPropertyDecl() == PD) {
3499          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3500            Dynamic = true;
3501          } else {
3502            SynthesizePID = PID;
3503          }
3504        }
3505      }
3506    } else {
3507      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
3508      for (ObjCCategoryImplDecl::propimpl_iterator
3509             i = OID->propimpl_begin(), e = OID->propimpl_end();
3510           i != e; ++i) {
3511        ObjCPropertyImplDecl *PID = *i;
3512        if (PID->getPropertyDecl() == PD) {
3513          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3514            Dynamic = true;
3515          } else {
3516            SynthesizePID = PID;
3517          }
3518        }
3519      }
3520    }
3521  }
3522
3523  // FIXME: This is not very efficient.
3524  S = "T";
3525
3526  // Encode result type.
3527  // GCC has some special rules regarding encoding of properties which
3528  // closely resembles encoding of ivars.
3529  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
3530                             true /* outermost type */,
3531                             true /* encoding for property */);
3532
3533  if (PD->isReadOnly()) {
3534    S += ",R";
3535  } else {
3536    switch (PD->getSetterKind()) {
3537    case ObjCPropertyDecl::Assign: break;
3538    case ObjCPropertyDecl::Copy:   S += ",C"; break;
3539    case ObjCPropertyDecl::Retain: S += ",&"; break;
3540    }
3541  }
3542
3543  // It really isn't clear at all what this means, since properties
3544  // are "dynamic by default".
3545  if (Dynamic)
3546    S += ",D";
3547
3548  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
3549    S += ",N";
3550
3551  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
3552    S += ",G";
3553    S += PD->getGetterName().getAsString();
3554  }
3555
3556  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
3557    S += ",S";
3558    S += PD->getSetterName().getAsString();
3559  }
3560
3561  if (SynthesizePID) {
3562    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
3563    S += ",V";
3564    S += OID->getNameAsString();
3565  }
3566
3567  // FIXME: OBJCGC: weak & strong
3568}
3569
3570/// getLegacyIntegralTypeEncoding -
3571/// Another legacy compatibility encoding: 32-bit longs are encoded as
3572/// 'l' or 'L' , but not always.  For typedefs, we need to use
3573/// 'i' or 'I' instead if encoding a struct field, or a pointer!
3574///
3575void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
3576  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
3577    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
3578      if (BT->getKind() == BuiltinType::ULong &&
3579          ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3580        PointeeTy = UnsignedIntTy;
3581      else
3582        if (BT->getKind() == BuiltinType::Long &&
3583            ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3584          PointeeTy = IntTy;
3585    }
3586  }
3587}
3588
3589void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
3590                                        const FieldDecl *Field) {
3591  // We follow the behavior of gcc, expanding structures which are
3592  // directly pointed to, and expanding embedded structures. Note that
3593  // these rules are sufficient to prevent recursive encoding of the
3594  // same type.
3595  getObjCEncodingForTypeImpl(T, S, true, true, Field,
3596                             true /* outermost type */);
3597}
3598
3599static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
3600    switch (T->getAs<BuiltinType>()->getKind()) {
3601    default: assert(0 && "Unhandled builtin type kind");
3602    case BuiltinType::Void:       return 'v';
3603    case BuiltinType::Bool:       return 'B';
3604    case BuiltinType::Char_U:
3605    case BuiltinType::UChar:      return 'C';
3606    case BuiltinType::UShort:     return 'S';
3607    case BuiltinType::UInt:       return 'I';
3608    case BuiltinType::ULong:
3609        return
3610          (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'L' : 'Q';
3611    case BuiltinType::UInt128:    return 'T';
3612    case BuiltinType::ULongLong:  return 'Q';
3613    case BuiltinType::Char_S:
3614    case BuiltinType::SChar:      return 'c';
3615    case BuiltinType::Short:      return 's';
3616    case BuiltinType::WChar:
3617    case BuiltinType::Int:        return 'i';
3618    case BuiltinType::Long:
3619      return
3620        (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'l' : 'q';
3621    case BuiltinType::LongLong:   return 'q';
3622    case BuiltinType::Int128:     return 't';
3623    case BuiltinType::Float:      return 'f';
3624    case BuiltinType::Double:     return 'd';
3625    case BuiltinType::LongDouble: return 'd';
3626    }
3627}
3628
3629static void EncodeBitField(const ASTContext *Context, std::string& S,
3630                           QualType T, const FieldDecl *FD) {
3631  const Expr *E = FD->getBitWidth();
3632  assert(E && "bitfield width not there - getObjCEncodingForTypeImpl");
3633  ASTContext *Ctx = const_cast<ASTContext*>(Context);
3634  S += 'b';
3635  // The NeXT runtime encodes bit fields as b followed by the number of bits.
3636  // The GNU runtime requires more information; bitfields are encoded as b,
3637  // then the offset (in bits) of the first element, then the type of the
3638  // bitfield, then the size in bits.  For example, in this structure:
3639  //
3640  // struct
3641  // {
3642  //    int integer;
3643  //    int flags:2;
3644  // };
3645  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
3646  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
3647  // information is not especially sensible, but we're stuck with it for
3648  // compatibility with GCC, although providing it breaks anything that
3649  // actually uses runtime introspection and wants to work on both runtimes...
3650  if (!Ctx->getLangOptions().NeXTRuntime) {
3651    const RecordDecl *RD = FD->getParent();
3652    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
3653    // FIXME: This same linear search is also used in ExprConstant - it might
3654    // be better if the FieldDecl stored its offset.  We'd be increasing the
3655    // size of the object slightly, but saving some time every time it is used.
3656    unsigned i = 0;
3657    for (RecordDecl::field_iterator Field = RD->field_begin(),
3658                                 FieldEnd = RD->field_end();
3659         Field != FieldEnd; (void)++Field, ++i) {
3660      if (*Field == FD)
3661        break;
3662    }
3663    S += llvm::utostr(RL.getFieldOffset(i));
3664    S += ObjCEncodingForPrimitiveKind(Context, T);
3665  }
3666  unsigned N = E->EvaluateAsInt(*Ctx).getZExtValue();
3667  S += llvm::utostr(N);
3668}
3669
3670// FIXME: Use SmallString for accumulating string.
3671void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
3672                                            bool ExpandPointedToStructures,
3673                                            bool ExpandStructures,
3674                                            const FieldDecl *FD,
3675                                            bool OutermostType,
3676                                            bool EncodingProperty) {
3677  if (T->getAs<BuiltinType>()) {
3678    if (FD && FD->isBitField())
3679      return EncodeBitField(this, S, T, FD);
3680    S += ObjCEncodingForPrimitiveKind(this, T);
3681    return;
3682  }
3683
3684  if (const ComplexType *CT = T->getAs<ComplexType>()) {
3685    S += 'j';
3686    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
3687                               false);
3688    return;
3689  }
3690
3691  // encoding for pointer or r3eference types.
3692  QualType PointeeTy;
3693  if (const PointerType *PT = T->getAs<PointerType>()) {
3694    if (PT->isObjCSelType()) {
3695      S += ':';
3696      return;
3697    }
3698    PointeeTy = PT->getPointeeType();
3699  }
3700  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3701    PointeeTy = RT->getPointeeType();
3702  if (!PointeeTy.isNull()) {
3703    bool isReadOnly = false;
3704    // For historical/compatibility reasons, the read-only qualifier of the
3705    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
3706    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
3707    // Also, do not emit the 'r' for anything but the outermost type!
3708    if (isa<TypedefType>(T.getTypePtr())) {
3709      if (OutermostType && T.isConstQualified()) {
3710        isReadOnly = true;
3711        S += 'r';
3712      }
3713    } else if (OutermostType) {
3714      QualType P = PointeeTy;
3715      while (P->getAs<PointerType>())
3716        P = P->getAs<PointerType>()->getPointeeType();
3717      if (P.isConstQualified()) {
3718        isReadOnly = true;
3719        S += 'r';
3720      }
3721    }
3722    if (isReadOnly) {
3723      // Another legacy compatibility encoding. Some ObjC qualifier and type
3724      // combinations need to be rearranged.
3725      // Rewrite "in const" from "nr" to "rn"
3726      if (llvm::StringRef(S).endswith("nr"))
3727        S.replace(S.end()-2, S.end(), "rn");
3728    }
3729
3730    if (PointeeTy->isCharType()) {
3731      // char pointer types should be encoded as '*' unless it is a
3732      // type that has been typedef'd to 'BOOL'.
3733      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
3734        S += '*';
3735        return;
3736      }
3737    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
3738      // GCC binary compat: Need to convert "struct objc_class *" to "#".
3739      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
3740        S += '#';
3741        return;
3742      }
3743      // GCC binary compat: Need to convert "struct objc_object *" to "@".
3744      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
3745        S += '@';
3746        return;
3747      }
3748      // fall through...
3749    }
3750    S += '^';
3751    getLegacyIntegralTypeEncoding(PointeeTy);
3752
3753    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
3754                               NULL);
3755    return;
3756  }
3757
3758  if (const ArrayType *AT =
3759      // Ignore type qualifiers etc.
3760        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
3761    if (isa<IncompleteArrayType>(AT)) {
3762      // Incomplete arrays are encoded as a pointer to the array element.
3763      S += '^';
3764
3765      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3766                                 false, ExpandStructures, FD);
3767    } else {
3768      S += '[';
3769
3770      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
3771        S += llvm::utostr(CAT->getSize().getZExtValue());
3772      else {
3773        //Variable length arrays are encoded as a regular array with 0 elements.
3774        assert(isa<VariableArrayType>(AT) && "Unknown array type!");
3775        S += '0';
3776      }
3777
3778      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3779                                 false, ExpandStructures, FD);
3780      S += ']';
3781    }
3782    return;
3783  }
3784
3785  if (T->getAs<FunctionType>()) {
3786    S += '?';
3787    return;
3788  }
3789
3790  if (const RecordType *RTy = T->getAs<RecordType>()) {
3791    RecordDecl *RDecl = RTy->getDecl();
3792    S += RDecl->isUnion() ? '(' : '{';
3793    // Anonymous structures print as '?'
3794    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
3795      S += II->getName();
3796      if (ClassTemplateSpecializationDecl *Spec
3797          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
3798        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
3799        std::string TemplateArgsStr
3800          = TemplateSpecializationType::PrintTemplateArgumentList(
3801                                            TemplateArgs.getFlatArgumentList(),
3802                                            TemplateArgs.flat_size(),
3803                                            (*this).PrintingPolicy);
3804
3805        S += TemplateArgsStr;
3806      }
3807    } else {
3808      S += '?';
3809    }
3810    if (ExpandStructures) {
3811      S += '=';
3812      for (RecordDecl::field_iterator Field = RDecl->field_begin(),
3813                                   FieldEnd = RDecl->field_end();
3814           Field != FieldEnd; ++Field) {
3815        if (FD) {
3816          S += '"';
3817          S += Field->getNameAsString();
3818          S += '"';
3819        }
3820
3821        // Special case bit-fields.
3822        if (Field->isBitField()) {
3823          getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
3824                                     (*Field));
3825        } else {
3826          QualType qt = Field->getType();
3827          getLegacyIntegralTypeEncoding(qt);
3828          getObjCEncodingForTypeImpl(qt, S, false, true,
3829                                     FD);
3830        }
3831      }
3832    }
3833    S += RDecl->isUnion() ? ')' : '}';
3834    return;
3835  }
3836
3837  if (T->isEnumeralType()) {
3838    if (FD && FD->isBitField())
3839      EncodeBitField(this, S, T, FD);
3840    else
3841      S += 'i';
3842    return;
3843  }
3844
3845  if (T->isBlockPointerType()) {
3846    S += "@?"; // Unlike a pointer-to-function, which is "^?".
3847    return;
3848  }
3849
3850  // Ignore protocol qualifiers when mangling at this level.
3851  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
3852    T = OT->getBaseType();
3853
3854  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
3855    // @encode(class_name)
3856    ObjCInterfaceDecl *OI = OIT->getDecl();
3857    S += '{';
3858    const IdentifierInfo *II = OI->getIdentifier();
3859    S += II->getName();
3860    S += '=';
3861    llvm::SmallVector<FieldDecl*, 32> RecFields;
3862    CollectObjCIvars(OI, RecFields);
3863    for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
3864      if (RecFields[i]->isBitField())
3865        getObjCEncodingForTypeImpl(RecFields[i]->getType(), S, false, true,
3866                                   RecFields[i]);
3867      else
3868        getObjCEncodingForTypeImpl(RecFields[i]->getType(), S, false, true,
3869                                   FD);
3870    }
3871    S += '}';
3872    return;
3873  }
3874
3875  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
3876    if (OPT->isObjCIdType()) {
3877      S += '@';
3878      return;
3879    }
3880
3881    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
3882      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
3883      // Since this is a binary compatibility issue, need to consult with runtime
3884      // folks. Fortunately, this is a *very* obsure construct.
3885      S += '#';
3886      return;
3887    }
3888
3889    if (OPT->isObjCQualifiedIdType()) {
3890      getObjCEncodingForTypeImpl(getObjCIdType(), S,
3891                                 ExpandPointedToStructures,
3892                                 ExpandStructures, FD);
3893      if (FD || EncodingProperty) {
3894        // Note that we do extended encoding of protocol qualifer list
3895        // Only when doing ivar or property encoding.
3896        S += '"';
3897        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3898             E = OPT->qual_end(); I != E; ++I) {
3899          S += '<';
3900          S += (*I)->getNameAsString();
3901          S += '>';
3902        }
3903        S += '"';
3904      }
3905      return;
3906    }
3907
3908    QualType PointeeTy = OPT->getPointeeType();
3909    if (!EncodingProperty &&
3910        isa<TypedefType>(PointeeTy.getTypePtr())) {
3911      // Another historical/compatibility reason.
3912      // We encode the underlying type which comes out as
3913      // {...};
3914      S += '^';
3915      getObjCEncodingForTypeImpl(PointeeTy, S,
3916                                 false, ExpandPointedToStructures,
3917                                 NULL);
3918      return;
3919    }
3920
3921    S += '@';
3922    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
3923      S += '"';
3924      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
3925      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3926           E = OPT->qual_end(); I != E; ++I) {
3927        S += '<';
3928        S += (*I)->getNameAsString();
3929        S += '>';
3930      }
3931      S += '"';
3932    }
3933    return;
3934  }
3935
3936  // gcc just blithely ignores member pointers.
3937  // TODO: maybe there should be a mangling for these
3938  if (T->getAs<MemberPointerType>())
3939    return;
3940
3941  assert(0 && "@encode for type not implemented!");
3942}
3943
3944void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
3945                                                 std::string& S) const {
3946  if (QT & Decl::OBJC_TQ_In)
3947    S += 'n';
3948  if (QT & Decl::OBJC_TQ_Inout)
3949    S += 'N';
3950  if (QT & Decl::OBJC_TQ_Out)
3951    S += 'o';
3952  if (QT & Decl::OBJC_TQ_Bycopy)
3953    S += 'O';
3954  if (QT & Decl::OBJC_TQ_Byref)
3955    S += 'R';
3956  if (QT & Decl::OBJC_TQ_Oneway)
3957    S += 'V';
3958}
3959
3960void ASTContext::setBuiltinVaListType(QualType T) {
3961  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
3962
3963  BuiltinVaListType = T;
3964}
3965
3966void ASTContext::setObjCIdType(QualType T) {
3967  ObjCIdTypedefType = T;
3968}
3969
3970void ASTContext::setObjCSelType(QualType T) {
3971  ObjCSelTypedefType = T;
3972}
3973
3974void ASTContext::setObjCProtoType(QualType QT) {
3975  ObjCProtoType = QT;
3976}
3977
3978void ASTContext::setObjCClassType(QualType T) {
3979  ObjCClassTypedefType = T;
3980}
3981
3982void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
3983  assert(ObjCConstantStringType.isNull() &&
3984         "'NSConstantString' type already set!");
3985
3986  ObjCConstantStringType = getObjCInterfaceType(Decl);
3987}
3988
3989/// \brief Retrieve the template name that corresponds to a non-empty
3990/// lookup.
3991TemplateName ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
3992                                                   UnresolvedSetIterator End) {
3993  unsigned size = End - Begin;
3994  assert(size > 1 && "set is not overloaded!");
3995
3996  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
3997                          size * sizeof(FunctionTemplateDecl*));
3998  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
3999
4000  NamedDecl **Storage = OT->getStorage();
4001  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4002    NamedDecl *D = *I;
4003    assert(isa<FunctionTemplateDecl>(D) ||
4004           (isa<UsingShadowDecl>(D) &&
4005            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4006    *Storage++ = D;
4007  }
4008
4009  return TemplateName(OT);
4010}
4011
4012/// \brief Retrieve the template name that represents a qualified
4013/// template name such as \c std::vector.
4014TemplateName ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4015                                                  bool TemplateKeyword,
4016                                                  TemplateDecl *Template) {
4017  // FIXME: Canonicalization?
4018  llvm::FoldingSetNodeID ID;
4019  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4020
4021  void *InsertPos = 0;
4022  QualifiedTemplateName *QTN =
4023    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4024  if (!QTN) {
4025    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4026    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4027  }
4028
4029  return TemplateName(QTN);
4030}
4031
4032/// \brief Retrieve the template name that represents a dependent
4033/// template name such as \c MetaFun::template apply.
4034TemplateName ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4035                                                  const IdentifierInfo *Name) {
4036  assert((!NNS || NNS->isDependent()) &&
4037         "Nested name specifier must be dependent");
4038
4039  llvm::FoldingSetNodeID ID;
4040  DependentTemplateName::Profile(ID, NNS, Name);
4041
4042  void *InsertPos = 0;
4043  DependentTemplateName *QTN =
4044    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4045
4046  if (QTN)
4047    return TemplateName(QTN);
4048
4049  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4050  if (CanonNNS == NNS) {
4051    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4052  } else {
4053    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4054    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4055    DependentTemplateName *CheckQTN =
4056      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4057    assert(!CheckQTN && "Dependent type name canonicalization broken");
4058    (void)CheckQTN;
4059  }
4060
4061  DependentTemplateNames.InsertNode(QTN, InsertPos);
4062  return TemplateName(QTN);
4063}
4064
4065/// \brief Retrieve the template name that represents a dependent
4066/// template name such as \c MetaFun::template operator+.
4067TemplateName
4068ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4069                                     OverloadedOperatorKind Operator) {
4070  assert((!NNS || NNS->isDependent()) &&
4071         "Nested name specifier must be dependent");
4072
4073  llvm::FoldingSetNodeID ID;
4074  DependentTemplateName::Profile(ID, NNS, Operator);
4075
4076  void *InsertPos = 0;
4077  DependentTemplateName *QTN
4078    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4079
4080  if (QTN)
4081    return TemplateName(QTN);
4082
4083  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4084  if (CanonNNS == NNS) {
4085    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4086  } else {
4087    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4088    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4089
4090    DependentTemplateName *CheckQTN
4091      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4092    assert(!CheckQTN && "Dependent template name canonicalization broken");
4093    (void)CheckQTN;
4094  }
4095
4096  DependentTemplateNames.InsertNode(QTN, InsertPos);
4097  return TemplateName(QTN);
4098}
4099
4100/// getFromTargetType - Given one of the integer types provided by
4101/// TargetInfo, produce the corresponding type. The unsigned @p Type
4102/// is actually a value of type @c TargetInfo::IntType.
4103CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4104  switch (Type) {
4105  case TargetInfo::NoInt: return CanQualType();
4106  case TargetInfo::SignedShort: return ShortTy;
4107  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4108  case TargetInfo::SignedInt: return IntTy;
4109  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4110  case TargetInfo::SignedLong: return LongTy;
4111  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4112  case TargetInfo::SignedLongLong: return LongLongTy;
4113  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4114  }
4115
4116  assert(false && "Unhandled TargetInfo::IntType value");
4117  return CanQualType();
4118}
4119
4120//===----------------------------------------------------------------------===//
4121//                        Type Predicates.
4122//===----------------------------------------------------------------------===//
4123
4124/// isObjCNSObjectType - Return true if this is an NSObject object using
4125/// NSObject attribute on a c-style pointer type.
4126/// FIXME - Make it work directly on types.
4127/// FIXME: Move to Type.
4128///
4129bool ASTContext::isObjCNSObjectType(QualType Ty) const {
4130  if (TypedefType *TDT = dyn_cast<TypedefType>(Ty)) {
4131    if (TypedefDecl *TD = TDT->getDecl())
4132      if (TD->getAttr<ObjCNSObjectAttr>())
4133        return true;
4134  }
4135  return false;
4136}
4137
4138/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4139/// garbage collection attribute.
4140///
4141Qualifiers::GC ASTContext::getObjCGCAttrKind(const QualType &Ty) const {
4142  Qualifiers::GC GCAttrs = Qualifiers::GCNone;
4143  if (getLangOptions().ObjC1 &&
4144      getLangOptions().getGCMode() != LangOptions::NonGC) {
4145    GCAttrs = Ty.getObjCGCAttr();
4146    // Default behavious under objective-c's gc is for objective-c pointers
4147    // (or pointers to them) be treated as though they were declared
4148    // as __strong.
4149    if (GCAttrs == Qualifiers::GCNone) {
4150      if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4151        GCAttrs = Qualifiers::Strong;
4152      else if (Ty->isPointerType())
4153        return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4154    }
4155    // Non-pointers have none gc'able attribute regardless of the attribute
4156    // set on them.
4157    else if (!Ty->isAnyPointerType() && !Ty->isBlockPointerType())
4158      return Qualifiers::GCNone;
4159  }
4160  return GCAttrs;
4161}
4162
4163//===----------------------------------------------------------------------===//
4164//                        Type Compatibility Testing
4165//===----------------------------------------------------------------------===//
4166
4167/// areCompatVectorTypes - Return true if the two specified vector types are
4168/// compatible.
4169static bool areCompatVectorTypes(const VectorType *LHS,
4170                                 const VectorType *RHS) {
4171  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
4172  return LHS->getElementType() == RHS->getElementType() &&
4173         LHS->getNumElements() == RHS->getNumElements();
4174}
4175
4176bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
4177                                          QualType SecondVec) {
4178  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
4179  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
4180
4181  if (hasSameUnqualifiedType(FirstVec, SecondVec))
4182    return true;
4183
4184  // AltiVec vectors types are identical to equivalent GCC vector types
4185  const VectorType *First = FirstVec->getAs<VectorType>();
4186  const VectorType *Second = SecondVec->getAs<VectorType>();
4187  if ((((First->getAltiVecSpecific() == VectorType::AltiVec) &&
4188        (Second->getAltiVecSpecific() == VectorType::NotAltiVec)) ||
4189       ((First->getAltiVecSpecific() == VectorType::NotAltiVec) &&
4190        (Second->getAltiVecSpecific() == VectorType::AltiVec))) &&
4191      hasSameType(First->getElementType(), Second->getElementType()) &&
4192      (First->getNumElements() == Second->getNumElements()))
4193    return true;
4194
4195  return false;
4196}
4197
4198//===----------------------------------------------------------------------===//
4199// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
4200//===----------------------------------------------------------------------===//
4201
4202/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
4203/// inheritance hierarchy of 'rProto'.
4204bool ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
4205                                                ObjCProtocolDecl *rProto) {
4206  if (lProto == rProto)
4207    return true;
4208  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
4209       E = rProto->protocol_end(); PI != E; ++PI)
4210    if (ProtocolCompatibleWithProtocol(lProto, *PI))
4211      return true;
4212  return false;
4213}
4214
4215/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
4216/// return true if lhs's protocols conform to rhs's protocol; false
4217/// otherwise.
4218bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
4219  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
4220    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
4221  return false;
4222}
4223
4224/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
4225/// Class<p1, ...>.
4226bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
4227                                                      QualType rhs) {
4228  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
4229  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4230  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
4231
4232  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4233       E = lhsQID->qual_end(); I != E; ++I) {
4234    bool match = false;
4235    ObjCProtocolDecl *lhsProto = *I;
4236    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4237         E = rhsOPT->qual_end(); J != E; ++J) {
4238      ObjCProtocolDecl *rhsProto = *J;
4239      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
4240        match = true;
4241        break;
4242      }
4243    }
4244    if (!match)
4245      return false;
4246  }
4247  return true;
4248}
4249
4250/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
4251/// ObjCQualifiedIDType.
4252bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
4253                                                   bool compare) {
4254  // Allow id<P..> and an 'id' or void* type in all cases.
4255  if (lhs->isVoidPointerType() ||
4256      lhs->isObjCIdType() || lhs->isObjCClassType())
4257    return true;
4258  else if (rhs->isVoidPointerType() ||
4259           rhs->isObjCIdType() || rhs->isObjCClassType())
4260    return true;
4261
4262  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
4263    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4264
4265    if (!rhsOPT) return false;
4266
4267    if (rhsOPT->qual_empty()) {
4268      // If the RHS is a unqualified interface pointer "NSString*",
4269      // make sure we check the class hierarchy.
4270      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4271        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4272             E = lhsQID->qual_end(); I != E; ++I) {
4273          // when comparing an id<P> on lhs with a static type on rhs,
4274          // see if static class implements all of id's protocols, directly or
4275          // through its super class and categories.
4276          if (!rhsID->ClassImplementsProtocol(*I, true))
4277            return false;
4278        }
4279      }
4280      // If there are no qualifiers and no interface, we have an 'id'.
4281      return true;
4282    }
4283    // Both the right and left sides have qualifiers.
4284    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4285         E = lhsQID->qual_end(); I != E; ++I) {
4286      ObjCProtocolDecl *lhsProto = *I;
4287      bool match = false;
4288
4289      // when comparing an id<P> on lhs with a static type on rhs,
4290      // see if static class implements all of id's protocols, directly or
4291      // through its super class and categories.
4292      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4293           E = rhsOPT->qual_end(); J != E; ++J) {
4294        ObjCProtocolDecl *rhsProto = *J;
4295        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4296            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4297          match = true;
4298          break;
4299        }
4300      }
4301      // If the RHS is a qualified interface pointer "NSString<P>*",
4302      // make sure we check the class hierarchy.
4303      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4304        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4305             E = lhsQID->qual_end(); I != E; ++I) {
4306          // when comparing an id<P> on lhs with a static type on rhs,
4307          // see if static class implements all of id's protocols, directly or
4308          // through its super class and categories.
4309          if (rhsID->ClassImplementsProtocol(*I, true)) {
4310            match = true;
4311            break;
4312          }
4313        }
4314      }
4315      if (!match)
4316        return false;
4317    }
4318
4319    return true;
4320  }
4321
4322  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
4323  assert(rhsQID && "One of the LHS/RHS should be id<x>");
4324
4325  if (const ObjCObjectPointerType *lhsOPT =
4326        lhs->getAsObjCInterfacePointerType()) {
4327    if (lhsOPT->qual_empty()) {
4328      bool match = false;
4329      if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
4330        for (ObjCObjectPointerType::qual_iterator I = rhsQID->qual_begin(),
4331             E = rhsQID->qual_end(); I != E; ++I) {
4332          // when comparing an id<P> on rhs with a static type on lhs,
4333          // static class must implement all of id's protocols directly or
4334          // indirectly through its super class.
4335          if (lhsID->ClassImplementsProtocol(*I, false)) {
4336            match = true;
4337            break;
4338          }
4339        }
4340        if (!match)
4341          return false;
4342      }
4343      return true;
4344    }
4345    // Both the right and left sides have qualifiers.
4346    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
4347         E = lhsOPT->qual_end(); I != E; ++I) {
4348      ObjCProtocolDecl *lhsProto = *I;
4349      bool match = false;
4350
4351      // when comparing an id<P> on lhs with a static type on rhs,
4352      // see if static class implements all of id's protocols, directly or
4353      // through its super class and categories.
4354      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4355           E = rhsQID->qual_end(); J != E; ++J) {
4356        ObjCProtocolDecl *rhsProto = *J;
4357        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4358            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4359          match = true;
4360          break;
4361        }
4362      }
4363      if (!match)
4364        return false;
4365    }
4366    return true;
4367  }
4368  return false;
4369}
4370
4371/// canAssignObjCInterfaces - Return true if the two interface types are
4372/// compatible for assignment from RHS to LHS.  This handles validation of any
4373/// protocol qualifiers on the LHS or RHS.
4374///
4375bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
4376                                         const ObjCObjectPointerType *RHSOPT) {
4377  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4378  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4379
4380  // If either type represents the built-in 'id' or 'Class' types, return true.
4381  if (LHS->isObjCUnqualifiedIdOrClass() ||
4382      RHS->isObjCUnqualifiedIdOrClass())
4383    return true;
4384
4385  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
4386    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4387                                             QualType(RHSOPT,0),
4388                                             false);
4389
4390  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
4391    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
4392                                                QualType(RHSOPT,0));
4393
4394  // If we have 2 user-defined types, fall into that path.
4395  if (LHS->getInterface() && RHS->getInterface())
4396    return canAssignObjCInterfaces(LHS, RHS);
4397
4398  return false;
4399}
4400
4401/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
4402/// for providing type-safty for objective-c pointers used to pass/return
4403/// arguments in block literals. When passed as arguments, passing 'A*' where
4404/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
4405/// not OK. For the return type, the opposite is not OK.
4406bool ASTContext::canAssignObjCInterfacesInBlockPointer(
4407                                         const ObjCObjectPointerType *LHSOPT,
4408                                         const ObjCObjectPointerType *RHSOPT) {
4409  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
4410    return true;
4411
4412  if (LHSOPT->isObjCBuiltinType()) {
4413    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
4414  }
4415
4416  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
4417    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4418                                             QualType(RHSOPT,0),
4419                                             false);
4420
4421  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
4422  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
4423  if (LHS && RHS)  { // We have 2 user-defined types.
4424    if (LHS != RHS) {
4425      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
4426        return false;
4427      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
4428        return true;
4429    }
4430    else
4431      return true;
4432  }
4433  return false;
4434}
4435
4436/// getIntersectionOfProtocols - This routine finds the intersection of set
4437/// of protocols inherited from two distinct objective-c pointer objects.
4438/// It is used to build composite qualifier list of the composite type of
4439/// the conditional expression involving two objective-c pointer objects.
4440static
4441void getIntersectionOfProtocols(ASTContext &Context,
4442                                const ObjCObjectPointerType *LHSOPT,
4443                                const ObjCObjectPointerType *RHSOPT,
4444      llvm::SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
4445
4446  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4447  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4448  assert(LHS->getInterface() && "LHS must have an interface base");
4449  assert(RHS->getInterface() && "RHS must have an interface base");
4450
4451  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
4452  unsigned LHSNumProtocols = LHS->getNumProtocols();
4453  if (LHSNumProtocols > 0)
4454    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
4455  else {
4456    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4457    Context.CollectInheritedProtocols(LHS->getInterface(),
4458                                      LHSInheritedProtocols);
4459    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
4460                                LHSInheritedProtocols.end());
4461  }
4462
4463  unsigned RHSNumProtocols = RHS->getNumProtocols();
4464  if (RHSNumProtocols > 0) {
4465    ObjCProtocolDecl **RHSProtocols =
4466      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
4467    for (unsigned i = 0; i < RHSNumProtocols; ++i)
4468      if (InheritedProtocolSet.count(RHSProtocols[i]))
4469        IntersectionOfProtocols.push_back(RHSProtocols[i]);
4470  }
4471  else {
4472    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
4473    Context.CollectInheritedProtocols(RHS->getInterface(),
4474                                      RHSInheritedProtocols);
4475    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4476         RHSInheritedProtocols.begin(),
4477         E = RHSInheritedProtocols.end(); I != E; ++I)
4478      if (InheritedProtocolSet.count((*I)))
4479        IntersectionOfProtocols.push_back((*I));
4480  }
4481}
4482
4483/// areCommonBaseCompatible - Returns common base class of the two classes if
4484/// one found. Note that this is O'2 algorithm. But it will be called as the
4485/// last type comparison in a ?-exp of ObjC pointer types before a
4486/// warning is issued. So, its invokation is extremely rare.
4487QualType ASTContext::areCommonBaseCompatible(
4488                                          const ObjCObjectPointerType *Lptr,
4489                                          const ObjCObjectPointerType *Rptr) {
4490  const ObjCObjectType *LHS = Lptr->getObjectType();
4491  const ObjCObjectType *RHS = Rptr->getObjectType();
4492  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
4493  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
4494  if (!LDecl || !RDecl)
4495    return QualType();
4496
4497  while ((LDecl = LDecl->getSuperClass())) {
4498    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
4499    if (canAssignObjCInterfaces(LHS, RHS)) {
4500      llvm::SmallVector<ObjCProtocolDecl *, 8> Protocols;
4501      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
4502
4503      QualType Result = QualType(LHS, 0);
4504      if (!Protocols.empty())
4505        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
4506      Result = getObjCObjectPointerType(Result);
4507      return Result;
4508    }
4509  }
4510
4511  return QualType();
4512}
4513
4514bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
4515                                         const ObjCObjectType *RHS) {
4516  assert(LHS->getInterface() && "LHS is not an interface type");
4517  assert(RHS->getInterface() && "RHS is not an interface type");
4518
4519  // Verify that the base decls are compatible: the RHS must be a subclass of
4520  // the LHS.
4521  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
4522    return false;
4523
4524  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
4525  // protocol qualified at all, then we are good.
4526  if (LHS->getNumProtocols() == 0)
4527    return true;
4528
4529  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't, then it
4530  // isn't a superset.
4531  if (RHS->getNumProtocols() == 0)
4532    return true;  // FIXME: should return false!
4533
4534  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
4535                                     LHSPE = LHS->qual_end();
4536       LHSPI != LHSPE; LHSPI++) {
4537    bool RHSImplementsProtocol = false;
4538
4539    // If the RHS doesn't implement the protocol on the left, the types
4540    // are incompatible.
4541    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
4542                                       RHSPE = RHS->qual_end();
4543         RHSPI != RHSPE; RHSPI++) {
4544      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
4545        RHSImplementsProtocol = true;
4546        break;
4547      }
4548    }
4549    // FIXME: For better diagnostics, consider passing back the protocol name.
4550    if (!RHSImplementsProtocol)
4551      return false;
4552  }
4553  // The RHS implements all protocols listed on the LHS.
4554  return true;
4555}
4556
4557bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
4558  // get the "pointed to" types
4559  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
4560  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
4561
4562  if (!LHSOPT || !RHSOPT)
4563    return false;
4564
4565  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
4566         canAssignObjCInterfaces(RHSOPT, LHSOPT);
4567}
4568
4569bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
4570  return canAssignObjCInterfaces(
4571                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
4572                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
4573}
4574
4575/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
4576/// both shall have the identically qualified version of a compatible type.
4577/// C99 6.2.7p1: Two types have compatible types if their types are the
4578/// same. See 6.7.[2,3,5] for additional rules.
4579bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
4580                                    bool CompareUnqualified) {
4581  if (getLangOptions().CPlusPlus)
4582    return hasSameType(LHS, RHS);
4583
4584  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
4585}
4586
4587bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
4588  return !mergeTypes(LHS, RHS, true).isNull();
4589}
4590
4591QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
4592                                        bool OfBlockPointer,
4593                                        bool Unqualified) {
4594  const FunctionType *lbase = lhs->getAs<FunctionType>();
4595  const FunctionType *rbase = rhs->getAs<FunctionType>();
4596  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
4597  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
4598  bool allLTypes = true;
4599  bool allRTypes = true;
4600
4601  // Check return type
4602  QualType retType;
4603  if (OfBlockPointer)
4604    retType = mergeTypes(rbase->getResultType(), lbase->getResultType(), true,
4605                         Unqualified);
4606  else
4607   retType = mergeTypes(lbase->getResultType(), rbase->getResultType(),
4608                        false, Unqualified);
4609  if (retType.isNull()) return QualType();
4610
4611  if (Unqualified)
4612    retType = retType.getUnqualifiedType();
4613
4614  CanQualType LRetType = getCanonicalType(lbase->getResultType());
4615  CanQualType RRetType = getCanonicalType(rbase->getResultType());
4616  if (Unqualified) {
4617    LRetType = LRetType.getUnqualifiedType();
4618    RRetType = RRetType.getUnqualifiedType();
4619  }
4620
4621  if (getCanonicalType(retType) != LRetType)
4622    allLTypes = false;
4623  if (getCanonicalType(retType) != RRetType)
4624    allRTypes = false;
4625  // FIXME: double check this
4626  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
4627  //                           rbase->getRegParmAttr() != 0 &&
4628  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
4629  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
4630  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
4631  unsigned RegParm = lbaseInfo.getRegParm() == 0 ? rbaseInfo.getRegParm() :
4632      lbaseInfo.getRegParm();
4633  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
4634  if (NoReturn != lbaseInfo.getNoReturn() ||
4635      RegParm != lbaseInfo.getRegParm())
4636    allLTypes = false;
4637  if (NoReturn != rbaseInfo.getNoReturn() ||
4638      RegParm != rbaseInfo.getRegParm())
4639    allRTypes = false;
4640  CallingConv lcc = lbaseInfo.getCC();
4641  CallingConv rcc = rbaseInfo.getCC();
4642  // Compatible functions must have compatible calling conventions
4643  if (!isSameCallConv(lcc, rcc))
4644    return QualType();
4645
4646  if (lproto && rproto) { // two C99 style function prototypes
4647    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
4648           "C++ shouldn't be here");
4649    unsigned lproto_nargs = lproto->getNumArgs();
4650    unsigned rproto_nargs = rproto->getNumArgs();
4651
4652    // Compatible functions must have the same number of arguments
4653    if (lproto_nargs != rproto_nargs)
4654      return QualType();
4655
4656    // Variadic and non-variadic functions aren't compatible
4657    if (lproto->isVariadic() != rproto->isVariadic())
4658      return QualType();
4659
4660    if (lproto->getTypeQuals() != rproto->getTypeQuals())
4661      return QualType();
4662
4663    // Check argument compatibility
4664    llvm::SmallVector<QualType, 10> types;
4665    for (unsigned i = 0; i < lproto_nargs; i++) {
4666      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
4667      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
4668      QualType argtype = mergeTypes(largtype, rargtype, OfBlockPointer,
4669                                    Unqualified);
4670      if (argtype.isNull()) return QualType();
4671
4672      if (Unqualified)
4673        argtype = argtype.getUnqualifiedType();
4674
4675      types.push_back(argtype);
4676      if (Unqualified) {
4677        largtype = largtype.getUnqualifiedType();
4678        rargtype = rargtype.getUnqualifiedType();
4679      }
4680
4681      if (getCanonicalType(argtype) != getCanonicalType(largtype))
4682        allLTypes = false;
4683      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
4684        allRTypes = false;
4685    }
4686    if (allLTypes) return lhs;
4687    if (allRTypes) return rhs;
4688    return getFunctionType(retType, types.begin(), types.size(),
4689                           lproto->isVariadic(), lproto->getTypeQuals(),
4690                           false, false, 0, 0,
4691                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4692  }
4693
4694  if (lproto) allRTypes = false;
4695  if (rproto) allLTypes = false;
4696
4697  const FunctionProtoType *proto = lproto ? lproto : rproto;
4698  if (proto) {
4699    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
4700    if (proto->isVariadic()) return QualType();
4701    // Check that the types are compatible with the types that
4702    // would result from default argument promotions (C99 6.7.5.3p15).
4703    // The only types actually affected are promotable integer
4704    // types and floats, which would be passed as a different
4705    // type depending on whether the prototype is visible.
4706    unsigned proto_nargs = proto->getNumArgs();
4707    for (unsigned i = 0; i < proto_nargs; ++i) {
4708      QualType argTy = proto->getArgType(i);
4709
4710      // Look at the promotion type of enum types, since that is the type used
4711      // to pass enum values.
4712      if (const EnumType *Enum = argTy->getAs<EnumType>())
4713        argTy = Enum->getDecl()->getPromotionType();
4714
4715      if (argTy->isPromotableIntegerType() ||
4716          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
4717        return QualType();
4718    }
4719
4720    if (allLTypes) return lhs;
4721    if (allRTypes) return rhs;
4722    return getFunctionType(retType, proto->arg_type_begin(),
4723                           proto->getNumArgs(), proto->isVariadic(),
4724                           proto->getTypeQuals(),
4725                           false, false, 0, 0,
4726                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4727  }
4728
4729  if (allLTypes) return lhs;
4730  if (allRTypes) return rhs;
4731  FunctionType::ExtInfo Info(NoReturn, RegParm, lcc);
4732  return getFunctionNoProtoType(retType, Info);
4733}
4734
4735QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
4736                                bool OfBlockPointer,
4737                                bool Unqualified) {
4738  // C++ [expr]: If an expression initially has the type "reference to T", the
4739  // type is adjusted to "T" prior to any further analysis, the expression
4740  // designates the object or function denoted by the reference, and the
4741  // expression is an lvalue unless the reference is an rvalue reference and
4742  // the expression is a function call (possibly inside parentheses).
4743  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
4744  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
4745
4746  if (Unqualified) {
4747    LHS = LHS.getUnqualifiedType();
4748    RHS = RHS.getUnqualifiedType();
4749  }
4750
4751  QualType LHSCan = getCanonicalType(LHS),
4752           RHSCan = getCanonicalType(RHS);
4753
4754  // If two types are identical, they are compatible.
4755  if (LHSCan == RHSCan)
4756    return LHS;
4757
4758  // If the qualifiers are different, the types aren't compatible... mostly.
4759  Qualifiers LQuals = LHSCan.getLocalQualifiers();
4760  Qualifiers RQuals = RHSCan.getLocalQualifiers();
4761  if (LQuals != RQuals) {
4762    // If any of these qualifiers are different, we have a type
4763    // mismatch.
4764    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
4765        LQuals.getAddressSpace() != RQuals.getAddressSpace())
4766      return QualType();
4767
4768    // Exactly one GC qualifier difference is allowed: __strong is
4769    // okay if the other type has no GC qualifier but is an Objective
4770    // C object pointer (i.e. implicitly strong by default).  We fix
4771    // this by pretending that the unqualified type was actually
4772    // qualified __strong.
4773    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
4774    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
4775    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
4776
4777    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
4778      return QualType();
4779
4780    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
4781      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
4782    }
4783    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
4784      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
4785    }
4786    return QualType();
4787  }
4788
4789  // Okay, qualifiers are equal.
4790
4791  Type::TypeClass LHSClass = LHSCan->getTypeClass();
4792  Type::TypeClass RHSClass = RHSCan->getTypeClass();
4793
4794  // We want to consider the two function types to be the same for these
4795  // comparisons, just force one to the other.
4796  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
4797  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
4798
4799  // Same as above for arrays
4800  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
4801    LHSClass = Type::ConstantArray;
4802  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
4803    RHSClass = Type::ConstantArray;
4804
4805  // ObjCInterfaces are just specialized ObjCObjects.
4806  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
4807  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
4808
4809  // Canonicalize ExtVector -> Vector.
4810  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
4811  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
4812
4813  // If the canonical type classes don't match.
4814  if (LHSClass != RHSClass) {
4815    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
4816    // a signed integer type, or an unsigned integer type.
4817    // Compatibility is based on the underlying type, not the promotion
4818    // type.
4819    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
4820      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
4821        return RHS;
4822    }
4823    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
4824      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
4825        return LHS;
4826    }
4827
4828    return QualType();
4829  }
4830
4831  // The canonical type classes match.
4832  switch (LHSClass) {
4833#define TYPE(Class, Base)
4834#define ABSTRACT_TYPE(Class, Base)
4835#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
4836#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
4837#define DEPENDENT_TYPE(Class, Base) case Type::Class:
4838#include "clang/AST/TypeNodes.def"
4839    assert(false && "Non-canonical and dependent types shouldn't get here");
4840    return QualType();
4841
4842  case Type::LValueReference:
4843  case Type::RValueReference:
4844  case Type::MemberPointer:
4845    assert(false && "C++ should never be in mergeTypes");
4846    return QualType();
4847
4848  case Type::ObjCInterface:
4849  case Type::IncompleteArray:
4850  case Type::VariableArray:
4851  case Type::FunctionProto:
4852  case Type::ExtVector:
4853    assert(false && "Types are eliminated above");
4854    return QualType();
4855
4856  case Type::Pointer:
4857  {
4858    // Merge two pointer types, while trying to preserve typedef info
4859    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
4860    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
4861    if (Unqualified) {
4862      LHSPointee = LHSPointee.getUnqualifiedType();
4863      RHSPointee = RHSPointee.getUnqualifiedType();
4864    }
4865    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
4866                                     Unqualified);
4867    if (ResultType.isNull()) return QualType();
4868    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
4869      return LHS;
4870    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
4871      return RHS;
4872    return getPointerType(ResultType);
4873  }
4874  case Type::BlockPointer:
4875  {
4876    // Merge two block pointer types, while trying to preserve typedef info
4877    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
4878    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
4879    if (Unqualified) {
4880      LHSPointee = LHSPointee.getUnqualifiedType();
4881      RHSPointee = RHSPointee.getUnqualifiedType();
4882    }
4883    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
4884                                     Unqualified);
4885    if (ResultType.isNull()) return QualType();
4886    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
4887      return LHS;
4888    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
4889      return RHS;
4890    return getBlockPointerType(ResultType);
4891  }
4892  case Type::ConstantArray:
4893  {
4894    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
4895    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
4896    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
4897      return QualType();
4898
4899    QualType LHSElem = getAsArrayType(LHS)->getElementType();
4900    QualType RHSElem = getAsArrayType(RHS)->getElementType();
4901    if (Unqualified) {
4902      LHSElem = LHSElem.getUnqualifiedType();
4903      RHSElem = RHSElem.getUnqualifiedType();
4904    }
4905
4906    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
4907    if (ResultType.isNull()) return QualType();
4908    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
4909      return LHS;
4910    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
4911      return RHS;
4912    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
4913                                          ArrayType::ArraySizeModifier(), 0);
4914    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
4915                                          ArrayType::ArraySizeModifier(), 0);
4916    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
4917    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
4918    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
4919      return LHS;
4920    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
4921      return RHS;
4922    if (LVAT) {
4923      // FIXME: This isn't correct! But tricky to implement because
4924      // the array's size has to be the size of LHS, but the type
4925      // has to be different.
4926      return LHS;
4927    }
4928    if (RVAT) {
4929      // FIXME: This isn't correct! But tricky to implement because
4930      // the array's size has to be the size of RHS, but the type
4931      // has to be different.
4932      return RHS;
4933    }
4934    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
4935    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
4936    return getIncompleteArrayType(ResultType,
4937                                  ArrayType::ArraySizeModifier(), 0);
4938  }
4939  case Type::FunctionNoProto:
4940    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
4941  case Type::Record:
4942  case Type::Enum:
4943    return QualType();
4944  case Type::Builtin:
4945    // Only exactly equal builtin types are compatible, which is tested above.
4946    return QualType();
4947  case Type::Complex:
4948    // Distinct complex types are incompatible.
4949    return QualType();
4950  case Type::Vector:
4951    // FIXME: The merged type should be an ExtVector!
4952    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
4953                             RHSCan->getAs<VectorType>()))
4954      return LHS;
4955    return QualType();
4956  case Type::ObjCObject: {
4957    // Check if the types are assignment compatible.
4958    // FIXME: This should be type compatibility, e.g. whether
4959    // "LHS x; RHS x;" at global scope is legal.
4960    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
4961    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
4962    if (canAssignObjCInterfaces(LHSIface, RHSIface))
4963      return LHS;
4964
4965    return QualType();
4966  }
4967  case Type::ObjCObjectPointer: {
4968    if (OfBlockPointer) {
4969      if (canAssignObjCInterfacesInBlockPointer(
4970                                          LHS->getAs<ObjCObjectPointerType>(),
4971                                          RHS->getAs<ObjCObjectPointerType>()))
4972      return LHS;
4973      return QualType();
4974    }
4975    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
4976                                RHS->getAs<ObjCObjectPointerType>()))
4977      return LHS;
4978
4979    return QualType();
4980    }
4981  }
4982
4983  return QualType();
4984}
4985
4986/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
4987/// 'RHS' attributes and returns the merged version; including for function
4988/// return types.
4989QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
4990  QualType LHSCan = getCanonicalType(LHS),
4991  RHSCan = getCanonicalType(RHS);
4992  // If two types are identical, they are compatible.
4993  if (LHSCan == RHSCan)
4994    return LHS;
4995  if (RHSCan->isFunctionType()) {
4996    if (!LHSCan->isFunctionType())
4997      return QualType();
4998    QualType OldReturnType =
4999      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
5000    QualType NewReturnType =
5001      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
5002    QualType ResReturnType =
5003      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
5004    if (ResReturnType.isNull())
5005      return QualType();
5006    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
5007      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
5008      // In either case, use OldReturnType to build the new function type.
5009      const FunctionType *F = LHS->getAs<FunctionType>();
5010      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
5011        FunctionType::ExtInfo Info = getFunctionExtInfo(LHS);
5012        QualType ResultType
5013          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
5014                                  FPT->getNumArgs(), FPT->isVariadic(),
5015                                  FPT->getTypeQuals(),
5016                                  FPT->hasExceptionSpec(),
5017                                  FPT->hasAnyExceptionSpec(),
5018                                  FPT->getNumExceptions(),
5019                                  FPT->exception_begin(),
5020                                  Info);
5021        return ResultType;
5022      }
5023    }
5024    return QualType();
5025  }
5026
5027  // If the qualifiers are different, the types can still be merged.
5028  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5029  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5030  if (LQuals != RQuals) {
5031    // If any of these qualifiers are different, we have a type mismatch.
5032    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5033        LQuals.getAddressSpace() != RQuals.getAddressSpace())
5034      return QualType();
5035
5036    // Exactly one GC qualifier difference is allowed: __strong is
5037    // okay if the other type has no GC qualifier but is an Objective
5038    // C object pointer (i.e. implicitly strong by default).  We fix
5039    // this by pretending that the unqualified type was actually
5040    // qualified __strong.
5041    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5042    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5043    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5044
5045    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5046      return QualType();
5047
5048    if (GC_L == Qualifiers::Strong)
5049      return LHS;
5050    if (GC_R == Qualifiers::Strong)
5051      return RHS;
5052    return QualType();
5053  }
5054
5055  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
5056    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5057    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5058    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
5059    if (ResQT == LHSBaseQT)
5060      return LHS;
5061    if (ResQT == RHSBaseQT)
5062      return RHS;
5063  }
5064  return QualType();
5065}
5066
5067//===----------------------------------------------------------------------===//
5068//                         Integer Predicates
5069//===----------------------------------------------------------------------===//
5070
5071unsigned ASTContext::getIntWidth(QualType T) {
5072  if (T->isBooleanType())
5073    return 1;
5074  if (EnumType *ET = dyn_cast<EnumType>(T))
5075    T = ET->getDecl()->getIntegerType();
5076  // For builtin types, just use the standard type sizing method
5077  return (unsigned)getTypeSize(T);
5078}
5079
5080QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
5081  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
5082
5083  // Turn <4 x signed int> -> <4 x unsigned int>
5084  if (const VectorType *VTy = T->getAs<VectorType>())
5085    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
5086             VTy->getNumElements(), VTy->getAltiVecSpecific());
5087
5088  // For enums, we return the unsigned version of the base type.
5089  if (const EnumType *ETy = T->getAs<EnumType>())
5090    T = ETy->getDecl()->getIntegerType();
5091
5092  const BuiltinType *BTy = T->getAs<BuiltinType>();
5093  assert(BTy && "Unexpected signed integer type");
5094  switch (BTy->getKind()) {
5095  case BuiltinType::Char_S:
5096  case BuiltinType::SChar:
5097    return UnsignedCharTy;
5098  case BuiltinType::Short:
5099    return UnsignedShortTy;
5100  case BuiltinType::Int:
5101    return UnsignedIntTy;
5102  case BuiltinType::Long:
5103    return UnsignedLongTy;
5104  case BuiltinType::LongLong:
5105    return UnsignedLongLongTy;
5106  case BuiltinType::Int128:
5107    return UnsignedInt128Ty;
5108  default:
5109    assert(0 && "Unexpected signed integer type");
5110    return QualType();
5111  }
5112}
5113
5114ExternalASTSource::~ExternalASTSource() { }
5115
5116void ExternalASTSource::PrintStats() { }
5117
5118
5119//===----------------------------------------------------------------------===//
5120//                          Builtin Type Computation
5121//===----------------------------------------------------------------------===//
5122
5123/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
5124/// pointer over the consumed characters.  This returns the resultant type.
5125static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
5126                                  ASTContext::GetBuiltinTypeError &Error,
5127                                  bool AllowTypeModifiers = true) {
5128  // Modifiers.
5129  int HowLong = 0;
5130  bool Signed = false, Unsigned = false;
5131
5132  // Read the modifiers first.
5133  bool Done = false;
5134  while (!Done) {
5135    switch (*Str++) {
5136    default: Done = true; --Str; break;
5137    case 'S':
5138      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
5139      assert(!Signed && "Can't use 'S' modifier multiple times!");
5140      Signed = true;
5141      break;
5142    case 'U':
5143      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
5144      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
5145      Unsigned = true;
5146      break;
5147    case 'L':
5148      assert(HowLong <= 2 && "Can't have LLLL modifier");
5149      ++HowLong;
5150      break;
5151    }
5152  }
5153
5154  QualType Type;
5155
5156  // Read the base type.
5157  switch (*Str++) {
5158  default: assert(0 && "Unknown builtin type letter!");
5159  case 'v':
5160    assert(HowLong == 0 && !Signed && !Unsigned &&
5161           "Bad modifiers used with 'v'!");
5162    Type = Context.VoidTy;
5163    break;
5164  case 'f':
5165    assert(HowLong == 0 && !Signed && !Unsigned &&
5166           "Bad modifiers used with 'f'!");
5167    Type = Context.FloatTy;
5168    break;
5169  case 'd':
5170    assert(HowLong < 2 && !Signed && !Unsigned &&
5171           "Bad modifiers used with 'd'!");
5172    if (HowLong)
5173      Type = Context.LongDoubleTy;
5174    else
5175      Type = Context.DoubleTy;
5176    break;
5177  case 's':
5178    assert(HowLong == 0 && "Bad modifiers used with 's'!");
5179    if (Unsigned)
5180      Type = Context.UnsignedShortTy;
5181    else
5182      Type = Context.ShortTy;
5183    break;
5184  case 'i':
5185    if (HowLong == 3)
5186      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
5187    else if (HowLong == 2)
5188      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
5189    else if (HowLong == 1)
5190      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
5191    else
5192      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
5193    break;
5194  case 'c':
5195    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
5196    if (Signed)
5197      Type = Context.SignedCharTy;
5198    else if (Unsigned)
5199      Type = Context.UnsignedCharTy;
5200    else
5201      Type = Context.CharTy;
5202    break;
5203  case 'b': // boolean
5204    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
5205    Type = Context.BoolTy;
5206    break;
5207  case 'z':  // size_t.
5208    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
5209    Type = Context.getSizeType();
5210    break;
5211  case 'F':
5212    Type = Context.getCFConstantStringType();
5213    break;
5214  case 'a':
5215    Type = Context.getBuiltinVaListType();
5216    assert(!Type.isNull() && "builtin va list type not initialized!");
5217    break;
5218  case 'A':
5219    // This is a "reference" to a va_list; however, what exactly
5220    // this means depends on how va_list is defined. There are two
5221    // different kinds of va_list: ones passed by value, and ones
5222    // passed by reference.  An example of a by-value va_list is
5223    // x86, where va_list is a char*. An example of by-ref va_list
5224    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
5225    // we want this argument to be a char*&; for x86-64, we want
5226    // it to be a __va_list_tag*.
5227    Type = Context.getBuiltinVaListType();
5228    assert(!Type.isNull() && "builtin va list type not initialized!");
5229    if (Type->isArrayType()) {
5230      Type = Context.getArrayDecayedType(Type);
5231    } else {
5232      Type = Context.getLValueReferenceType(Type);
5233    }
5234    break;
5235  case 'V': {
5236    char *End;
5237    unsigned NumElements = strtoul(Str, &End, 10);
5238    assert(End != Str && "Missing vector size");
5239
5240    Str = End;
5241
5242    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, false);
5243    // FIXME: Don't know what to do about AltiVec.
5244    Type = Context.getVectorType(ElementType, NumElements,
5245                                 VectorType::NotAltiVec);
5246    break;
5247  }
5248  case 'X': {
5249    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, false);
5250    Type = Context.getComplexType(ElementType);
5251    break;
5252  }
5253  case 'P':
5254    Type = Context.getFILEType();
5255    if (Type.isNull()) {
5256      Error = ASTContext::GE_Missing_stdio;
5257      return QualType();
5258    }
5259    break;
5260  case 'J':
5261    if (Signed)
5262      Type = Context.getsigjmp_bufType();
5263    else
5264      Type = Context.getjmp_bufType();
5265
5266    if (Type.isNull()) {
5267      Error = ASTContext::GE_Missing_setjmp;
5268      return QualType();
5269    }
5270    break;
5271  }
5272
5273  if (!AllowTypeModifiers)
5274    return Type;
5275
5276  Done = false;
5277  while (!Done) {
5278    switch (char c = *Str++) {
5279      default: Done = true; --Str; break;
5280      case '*':
5281      case '&':
5282        {
5283          // Both pointers and references can have their pointee types
5284          // qualified with an address space.
5285          char *End;
5286          unsigned AddrSpace = strtoul(Str, &End, 10);
5287          if (End != Str && AddrSpace != 0) {
5288            Type = Context.getAddrSpaceQualType(Type, AddrSpace);
5289            Str = End;
5290          }
5291        }
5292        if (c == '*')
5293          Type = Context.getPointerType(Type);
5294        else
5295          Type = Context.getLValueReferenceType(Type);
5296        break;
5297      // FIXME: There's no way to have a built-in with an rvalue ref arg.
5298      case 'C':
5299        Type = Type.withConst();
5300        break;
5301      case 'D':
5302        Type = Context.getVolatileType(Type);
5303        break;
5304    }
5305  }
5306
5307  return Type;
5308}
5309
5310/// GetBuiltinType - Return the type for the specified builtin.
5311QualType ASTContext::GetBuiltinType(unsigned id,
5312                                    GetBuiltinTypeError &Error) {
5313  const char *TypeStr = BuiltinInfo.GetTypeString(id);
5314
5315  llvm::SmallVector<QualType, 8> ArgTypes;
5316
5317  Error = GE_None;
5318  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error);
5319  if (Error != GE_None)
5320    return QualType();
5321  while (TypeStr[0] && TypeStr[0] != '.') {
5322    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error);
5323    if (Error != GE_None)
5324      return QualType();
5325
5326    // Do array -> pointer decay.  The builtin should use the decayed type.
5327    if (Ty->isArrayType())
5328      Ty = getArrayDecayedType(Ty);
5329
5330    ArgTypes.push_back(Ty);
5331  }
5332
5333  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
5334         "'.' should only occur at end of builtin type list!");
5335
5336  // handle untyped/variadic arguments "T c99Style();" or "T cppStyle(...);".
5337  if (ArgTypes.size() == 0 && TypeStr[0] == '.')
5338    return getFunctionNoProtoType(ResType);
5339
5340  // FIXME: Should we create noreturn types?
5341  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(),
5342                         TypeStr[0] == '.', 0, false, false, 0, 0,
5343                         FunctionType::ExtInfo());
5344}
5345
5346QualType
5347ASTContext::UsualArithmeticConversionsType(QualType lhs, QualType rhs) {
5348  // Perform the usual unary conversions. We do this early so that
5349  // integral promotions to "int" can allow us to exit early, in the
5350  // lhs == rhs check. Also, for conversion purposes, we ignore any
5351  // qualifiers.  For example, "const float" and "float" are
5352  // equivalent.
5353  if (lhs->isPromotableIntegerType())
5354    lhs = getPromotedIntegerType(lhs);
5355  else
5356    lhs = lhs.getUnqualifiedType();
5357  if (rhs->isPromotableIntegerType())
5358    rhs = getPromotedIntegerType(rhs);
5359  else
5360    rhs = rhs.getUnqualifiedType();
5361
5362  // If both types are identical, no conversion is needed.
5363  if (lhs == rhs)
5364    return lhs;
5365
5366  // If either side is a non-arithmetic type (e.g. a pointer), we are done.
5367  // The caller can deal with this (e.g. pointer + int).
5368  if (!lhs->isArithmeticType() || !rhs->isArithmeticType())
5369    return lhs;
5370
5371  // At this point, we have two different arithmetic types.
5372
5373  // Handle complex types first (C99 6.3.1.8p1).
5374  if (lhs->isComplexType() || rhs->isComplexType()) {
5375    // if we have an integer operand, the result is the complex type.
5376    if (rhs->isIntegerType() || rhs->isComplexIntegerType()) {
5377      // convert the rhs to the lhs complex type.
5378      return lhs;
5379    }
5380    if (lhs->isIntegerType() || lhs->isComplexIntegerType()) {
5381      // convert the lhs to the rhs complex type.
5382      return rhs;
5383    }
5384    // This handles complex/complex, complex/float, or float/complex.
5385    // When both operands are complex, the shorter operand is converted to the
5386    // type of the longer, and that is the type of the result. This corresponds
5387    // to what is done when combining two real floating-point operands.
5388    // The fun begins when size promotion occur across type domains.
5389    // From H&S 6.3.4: When one operand is complex and the other is a real
5390    // floating-point type, the less precise type is converted, within it's
5391    // real or complex domain, to the precision of the other type. For example,
5392    // when combining a "long double" with a "double _Complex", the
5393    // "double _Complex" is promoted to "long double _Complex".
5394    int result = getFloatingTypeOrder(lhs, rhs);
5395
5396    if (result > 0) { // The left side is bigger, convert rhs.
5397      rhs = getFloatingTypeOfSizeWithinDomain(lhs, rhs);
5398    } else if (result < 0) { // The right side is bigger, convert lhs.
5399      lhs = getFloatingTypeOfSizeWithinDomain(rhs, lhs);
5400    }
5401    // At this point, lhs and rhs have the same rank/size. Now, make sure the
5402    // domains match. This is a requirement for our implementation, C99
5403    // does not require this promotion.
5404    if (lhs != rhs) { // Domains don't match, we have complex/float mix.
5405      if (lhs->isRealFloatingType()) { // handle "double, _Complex double".
5406        return rhs;
5407      } else { // handle "_Complex double, double".
5408        return lhs;
5409      }
5410    }
5411    return lhs; // The domain/size match exactly.
5412  }
5413  // Now handle "real" floating types (i.e. float, double, long double).
5414  if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) {
5415    // if we have an integer operand, the result is the real floating type.
5416    if (rhs->isIntegerType()) {
5417      // convert rhs to the lhs floating point type.
5418      return lhs;
5419    }
5420    if (rhs->isComplexIntegerType()) {
5421      // convert rhs to the complex floating point type.
5422      return getComplexType(lhs);
5423    }
5424    if (lhs->isIntegerType()) {
5425      // convert lhs to the rhs floating point type.
5426      return rhs;
5427    }
5428    if (lhs->isComplexIntegerType()) {
5429      // convert lhs to the complex floating point type.
5430      return getComplexType(rhs);
5431    }
5432    // We have two real floating types, float/complex combos were handled above.
5433    // Convert the smaller operand to the bigger result.
5434    int result = getFloatingTypeOrder(lhs, rhs);
5435    if (result > 0) // convert the rhs
5436      return lhs;
5437    assert(result < 0 && "illegal float comparison");
5438    return rhs;   // convert the lhs
5439  }
5440  if (lhs->isComplexIntegerType() || rhs->isComplexIntegerType()) {
5441    // Handle GCC complex int extension.
5442    const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType();
5443    const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType();
5444
5445    if (lhsComplexInt && rhsComplexInt) {
5446      if (getIntegerTypeOrder(lhsComplexInt->getElementType(),
5447                              rhsComplexInt->getElementType()) >= 0)
5448        return lhs; // convert the rhs
5449      return rhs;
5450    } else if (lhsComplexInt && rhs->isIntegerType()) {
5451      // convert the rhs to the lhs complex type.
5452      return lhs;
5453    } else if (rhsComplexInt && lhs->isIntegerType()) {
5454      // convert the lhs to the rhs complex type.
5455      return rhs;
5456    }
5457  }
5458  // Finally, we have two differing integer types.
5459  // The rules for this case are in C99 6.3.1.8
5460  int compare = getIntegerTypeOrder(lhs, rhs);
5461  bool lhsSigned = lhs->hasSignedIntegerRepresentation(),
5462       rhsSigned = rhs->hasSignedIntegerRepresentation();
5463  QualType destType;
5464  if (lhsSigned == rhsSigned) {
5465    // Same signedness; use the higher-ranked type
5466    destType = compare >= 0 ? lhs : rhs;
5467  } else if (compare != (lhsSigned ? 1 : -1)) {
5468    // The unsigned type has greater than or equal rank to the
5469    // signed type, so use the unsigned type
5470    destType = lhsSigned ? rhs : lhs;
5471  } else if (getIntWidth(lhs) != getIntWidth(rhs)) {
5472    // The two types are different widths; if we are here, that
5473    // means the signed type is larger than the unsigned type, so
5474    // use the signed type.
5475    destType = lhsSigned ? lhs : rhs;
5476  } else {
5477    // The signed type is higher-ranked than the unsigned type,
5478    // but isn't actually any bigger (like unsigned int and long
5479    // on most 32-bit systems).  Use the unsigned type corresponding
5480    // to the signed type.
5481    destType = getCorrespondingUnsignedType(lhsSigned ? lhs : rhs);
5482  }
5483  return destType;
5484}
5485
5486GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
5487  GVALinkage External = GVA_StrongExternal;
5488
5489  Linkage L = FD->getLinkage();
5490  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5491      FD->getType()->getLinkage() == UniqueExternalLinkage)
5492    L = UniqueExternalLinkage;
5493
5494  switch (L) {
5495  case NoLinkage:
5496  case InternalLinkage:
5497  case UniqueExternalLinkage:
5498    return GVA_Internal;
5499
5500  case ExternalLinkage:
5501    switch (FD->getTemplateSpecializationKind()) {
5502    case TSK_Undeclared:
5503    case TSK_ExplicitSpecialization:
5504      External = GVA_StrongExternal;
5505      break;
5506
5507    case TSK_ExplicitInstantiationDefinition:
5508      return GVA_ExplicitTemplateInstantiation;
5509
5510    case TSK_ExplicitInstantiationDeclaration:
5511    case TSK_ImplicitInstantiation:
5512      External = GVA_TemplateInstantiation;
5513      break;
5514    }
5515  }
5516
5517  if (!FD->isInlined())
5518    return External;
5519
5520  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
5521    // GNU or C99 inline semantics. Determine whether this symbol should be
5522    // externally visible.
5523    if (FD->isInlineDefinitionExternallyVisible())
5524      return External;
5525
5526    // C99 inline semantics, where the symbol is not externally visible.
5527    return GVA_C99Inline;
5528  }
5529
5530  // C++0x [temp.explicit]p9:
5531  //   [ Note: The intent is that an inline function that is the subject of
5532  //   an explicit instantiation declaration will still be implicitly
5533  //   instantiated when used so that the body can be considered for
5534  //   inlining, but that no out-of-line copy of the inline function would be
5535  //   generated in the translation unit. -- end note ]
5536  if (FD->getTemplateSpecializationKind()
5537                                       == TSK_ExplicitInstantiationDeclaration)
5538    return GVA_C99Inline;
5539
5540  return GVA_CXXInline;
5541}
5542
5543GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
5544  // If this is a static data member, compute the kind of template
5545  // specialization. Otherwise, this variable is not part of a
5546  // template.
5547  TemplateSpecializationKind TSK = TSK_Undeclared;
5548  if (VD->isStaticDataMember())
5549    TSK = VD->getTemplateSpecializationKind();
5550
5551  Linkage L = VD->getLinkage();
5552  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5553      VD->getType()->getLinkage() == UniqueExternalLinkage)
5554    L = UniqueExternalLinkage;
5555
5556  switch (L) {
5557  case NoLinkage:
5558  case InternalLinkage:
5559  case UniqueExternalLinkage:
5560    return GVA_Internal;
5561
5562  case ExternalLinkage:
5563    switch (TSK) {
5564    case TSK_Undeclared:
5565    case TSK_ExplicitSpecialization:
5566      return GVA_StrongExternal;
5567
5568    case TSK_ExplicitInstantiationDeclaration:
5569      llvm_unreachable("Variable should not be instantiated");
5570      // Fall through to treat this like any other instantiation.
5571
5572    case TSK_ExplicitInstantiationDefinition:
5573      return GVA_ExplicitTemplateInstantiation;
5574
5575    case TSK_ImplicitInstantiation:
5576      return GVA_TemplateInstantiation;
5577    }
5578  }
5579
5580  return GVA_StrongExternal;
5581}
5582
5583bool ASTContext::DeclMustBeEmitted(const Decl *D) {
5584  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
5585    if (!VD->isFileVarDecl())
5586      return false;
5587  } else if (!isa<FunctionDecl>(D))
5588    return false;
5589
5590  // Weak references don't produce any output by themselves.
5591  if (D->hasAttr<WeakRefAttr>())
5592    return false;
5593
5594  // Aliases and used decls are required.
5595  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
5596    return true;
5597
5598  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
5599    // Forward declarations aren't required.
5600    if (!FD->isThisDeclarationADefinition())
5601      return false;
5602
5603    // Constructors and destructors are required.
5604    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
5605      return true;
5606
5607    // The key function for a class is required.
5608    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
5609      const CXXRecordDecl *RD = MD->getParent();
5610      if (MD->isOutOfLine() && RD->isDynamicClass()) {
5611        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
5612        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
5613          return true;
5614      }
5615    }
5616
5617    GVALinkage Linkage = GetGVALinkageForFunction(FD);
5618
5619    // static, static inline, always_inline, and extern inline functions can
5620    // always be deferred.  Normal inline functions can be deferred in C99/C++.
5621    // Implicit template instantiations can also be deferred in C++.
5622    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
5623        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
5624      return false;
5625    return true;
5626  }
5627
5628  const VarDecl *VD = cast<VarDecl>(D);
5629  assert(VD->isFileVarDecl() && "Expected file scoped var");
5630
5631  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
5632    return false;
5633
5634  // Structs that have non-trivial constructors or destructors are required.
5635
5636  // FIXME: Handle references.
5637  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
5638    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
5639      if (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor())
5640        return true;
5641    }
5642  }
5643
5644  GVALinkage L = GetGVALinkageForVariable(VD);
5645  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
5646    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
5647      return false;
5648  }
5649
5650  return true;
5651}
5652