ASTContext.cpp revision 006113841bdae1edb77aef75ba1ffdf2e55a3094 
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                       bool FreeMem, 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), FreeMemory(FreeMem), 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  if (!FreeMemory) {
170    // Call all of the deallocation functions.
171    for (unsigned I = 0, N = Deallocations.size(); I != N; ++I)
172      Deallocations[I].first(Deallocations[I].second);
173  }
174
175  // Release all of the memory associated with overridden C++ methods.
176  for (llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::iterator
177         OM = OverriddenMethods.begin(), OMEnd = OverriddenMethods.end();
178       OM != OMEnd; ++OM)
179    OM->second.Destroy();
180
181  if (FreeMemory) {
182    // Deallocate all the types.
183    while (!Types.empty()) {
184      Types.back()->Destroy(*this);
185      Types.pop_back();
186    }
187
188    for (llvm::FoldingSet<ExtQuals>::iterator
189         I = ExtQualNodes.begin(), E = ExtQualNodes.end(); I != E; ) {
190      // Increment in loop to prevent using deallocated memory.
191      Deallocate(&*I++);
192    }
193
194    for (llvm::DenseMap<const ObjCContainerDecl*,
195         const ASTRecordLayout*>::iterator
196         I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; ) {
197      // Increment in loop to prevent using deallocated memory.
198      if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
199        R->Destroy(*this);
200    }
201  }
202
203  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
204  // even when using the BumpPtrAllocator because they can contain
205  // DenseMaps.
206  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
207       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
208    // Increment in loop to prevent using deallocated memory.
209    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
210      R->Destroy(*this);
211  }
212
213  // Destroy nested-name-specifiers.
214  for (llvm::FoldingSet<NestedNameSpecifier>::iterator
215         NNS = NestedNameSpecifiers.begin(),
216         NNSEnd = NestedNameSpecifiers.end();
217       NNS != NNSEnd; ) {
218    // Increment in loop to prevent using deallocated memory.
219    (*NNS++).Destroy(*this);
220  }
221
222  if (GlobalNestedNameSpecifier)
223    GlobalNestedNameSpecifier->Destroy(*this);
224
225  TUDecl->Destroy(*this);
226}
227
228void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
229  Deallocations.push_back(std::make_pair(Callback, Data));
230}
231
232void
233ASTContext::setExternalSource(llvm::OwningPtr<ExternalASTSource> &Source) {
234  ExternalSource.reset(Source.take());
235}
236
237void ASTContext::PrintStats() const {
238  fprintf(stderr, "*** AST Context Stats:\n");
239  fprintf(stderr, "  %d types total.\n", (int)Types.size());
240
241  unsigned counts[] = {
242#define TYPE(Name, Parent) 0,
243#define ABSTRACT_TYPE(Name, Parent)
244#include "clang/AST/TypeNodes.def"
245    0 // Extra
246  };
247
248  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
249    Type *T = Types[i];
250    counts[(unsigned)T->getTypeClass()]++;
251  }
252
253  unsigned Idx = 0;
254  unsigned TotalBytes = 0;
255#define TYPE(Name, Parent)                                              \
256  if (counts[Idx])                                                      \
257    fprintf(stderr, "    %d %s types\n", (int)counts[Idx], #Name);      \
258  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
259  ++Idx;
260#define ABSTRACT_TYPE(Name, Parent)
261#include "clang/AST/TypeNodes.def"
262
263  fprintf(stderr, "Total bytes = %d\n", int(TotalBytes));
264
265  // Implicit special member functions.
266  fprintf(stderr, "  %u/%u implicit default constructors created\n",
267          NumImplicitDefaultConstructorsDeclared,
268          NumImplicitDefaultConstructors);
269  fprintf(stderr, "  %u/%u implicit copy constructors created\n",
270          NumImplicitCopyConstructorsDeclared,
271          NumImplicitCopyConstructors);
272  fprintf(stderr, "  %u/%u implicit copy assignment operators created\n",
273          NumImplicitCopyAssignmentOperatorsDeclared,
274          NumImplicitCopyAssignmentOperators);
275  fprintf(stderr, "  %u/%u implicit destructors created\n",
276          NumImplicitDestructorsDeclared, NumImplicitDestructors);
277
278  if (ExternalSource.get()) {
279    fprintf(stderr, "\n");
280    ExternalSource->PrintStats();
281  }
282}
283
284
285void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
286  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
287  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
288  Types.push_back(Ty);
289}
290
291void ASTContext::InitBuiltinTypes() {
292  assert(VoidTy.isNull() && "Context reinitialized?");
293
294  // C99 6.2.5p19.
295  InitBuiltinType(VoidTy,              BuiltinType::Void);
296
297  // C99 6.2.5p2.
298  InitBuiltinType(BoolTy,              BuiltinType::Bool);
299  // C99 6.2.5p3.
300  if (LangOpts.CharIsSigned)
301    InitBuiltinType(CharTy,            BuiltinType::Char_S);
302  else
303    InitBuiltinType(CharTy,            BuiltinType::Char_U);
304  // C99 6.2.5p4.
305  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
306  InitBuiltinType(ShortTy,             BuiltinType::Short);
307  InitBuiltinType(IntTy,               BuiltinType::Int);
308  InitBuiltinType(LongTy,              BuiltinType::Long);
309  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
310
311  // C99 6.2.5p6.
312  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
313  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
314  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
315  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
316  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
317
318  // C99 6.2.5p10.
319  InitBuiltinType(FloatTy,             BuiltinType::Float);
320  InitBuiltinType(DoubleTy,            BuiltinType::Double);
321  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
322
323  // GNU extension, 128-bit integers.
324  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
325  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
326
327  if (LangOpts.CPlusPlus) // C++ 3.9.1p5
328    InitBuiltinType(WCharTy,           BuiltinType::WChar);
329  else // C99
330    WCharTy = getFromTargetType(Target.getWCharType());
331
332  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
333    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
334  else // C99
335    Char16Ty = getFromTargetType(Target.getChar16Type());
336
337  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
338    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
339  else // C99
340    Char32Ty = getFromTargetType(Target.getChar32Type());
341
342  // Placeholder type for functions.
343  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
344
345  // Placeholder type for type-dependent expressions whose type is
346  // completely unknown. No code should ever check a type against
347  // DependentTy and users should never see it; however, it is here to
348  // help diagnose failures to properly check for type-dependent
349  // expressions.
350  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
351
352  // Placeholder type for C++0x auto declarations whose real type has
353  // not yet been deduced.
354  InitBuiltinType(UndeducedAutoTy, BuiltinType::UndeducedAuto);
355
356  // C99 6.2.5p11.
357  FloatComplexTy      = getComplexType(FloatTy);
358  DoubleComplexTy     = getComplexType(DoubleTy);
359  LongDoubleComplexTy = getComplexType(LongDoubleTy);
360
361  BuiltinVaListType = QualType();
362
363  // "Builtin" typedefs set by Sema::ActOnTranslationUnitScope().
364  ObjCIdTypedefType = QualType();
365  ObjCClassTypedefType = QualType();
366  ObjCSelTypedefType = QualType();
367
368  // Builtin types for 'id', 'Class', and 'SEL'.
369  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
370  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
371  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
372
373  ObjCConstantStringType = QualType();
374
375  // void * type
376  VoidPtrTy = getPointerType(VoidTy);
377
378  // nullptr type (C++0x 2.14.7)
379  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
380}
381
382MemberSpecializationInfo *
383ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
384  assert(Var->isStaticDataMember() && "Not a static data member");
385  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
386    = InstantiatedFromStaticDataMember.find(Var);
387  if (Pos == InstantiatedFromStaticDataMember.end())
388    return 0;
389
390  return Pos->second;
391}
392
393void
394ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
395                                                TemplateSpecializationKind TSK,
396                                          SourceLocation PointOfInstantiation) {
397  assert(Inst->isStaticDataMember() && "Not a static data member");
398  assert(Tmpl->isStaticDataMember() && "Not a static data member");
399  assert(!InstantiatedFromStaticDataMember[Inst] &&
400         "Already noted what static data member was instantiated from");
401  InstantiatedFromStaticDataMember[Inst]
402    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
403}
404
405NamedDecl *
406ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
407  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
408    = InstantiatedFromUsingDecl.find(UUD);
409  if (Pos == InstantiatedFromUsingDecl.end())
410    return 0;
411
412  return Pos->second;
413}
414
415void
416ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
417  assert((isa<UsingDecl>(Pattern) ||
418          isa<UnresolvedUsingValueDecl>(Pattern) ||
419          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
420         "pattern decl is not a using decl");
421  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
422  InstantiatedFromUsingDecl[Inst] = Pattern;
423}
424
425UsingShadowDecl *
426ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
427  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
428    = InstantiatedFromUsingShadowDecl.find(Inst);
429  if (Pos == InstantiatedFromUsingShadowDecl.end())
430    return 0;
431
432  return Pos->second;
433}
434
435void
436ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
437                                               UsingShadowDecl *Pattern) {
438  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
439  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
440}
441
442FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
443  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
444    = InstantiatedFromUnnamedFieldDecl.find(Field);
445  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
446    return 0;
447
448  return Pos->second;
449}
450
451void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
452                                                     FieldDecl *Tmpl) {
453  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
454  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
455  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
456         "Already noted what unnamed field was instantiated from");
457
458  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
459}
460
461ASTContext::overridden_cxx_method_iterator
462ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
463  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
464    = OverriddenMethods.find(Method);
465  if (Pos == OverriddenMethods.end())
466    return 0;
467
468  return Pos->second.begin();
469}
470
471ASTContext::overridden_cxx_method_iterator
472ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
473  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
474    = OverriddenMethods.find(Method);
475  if (Pos == OverriddenMethods.end())
476    return 0;
477
478  return Pos->second.end();
479}
480
481void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
482                                     const CXXMethodDecl *Overridden) {
483  OverriddenMethods[Method].push_back(Overridden);
484}
485
486namespace {
487  class BeforeInTranslationUnit
488    : std::binary_function<SourceRange, SourceRange, bool> {
489    SourceManager *SourceMgr;
490
491  public:
492    explicit BeforeInTranslationUnit(SourceManager *SM) : SourceMgr(SM) { }
493
494    bool operator()(SourceRange X, SourceRange Y) {
495      return SourceMgr->isBeforeInTranslationUnit(X.getBegin(), Y.getBegin());
496    }
497  };
498}
499
500//===----------------------------------------------------------------------===//
501//                         Type Sizing and Analysis
502//===----------------------------------------------------------------------===//
503
504/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
505/// scalar floating point type.
506const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
507  const BuiltinType *BT = T->getAs<BuiltinType>();
508  assert(BT && "Not a floating point type!");
509  switch (BT->getKind()) {
510  default: assert(0 && "Not a floating point type!");
511  case BuiltinType::Float:      return Target.getFloatFormat();
512  case BuiltinType::Double:     return Target.getDoubleFormat();
513  case BuiltinType::LongDouble: return Target.getLongDoubleFormat();
514  }
515}
516
517/// getDeclAlign - Return a conservative estimate of the alignment of the
518/// specified decl.  Note that bitfields do not have a valid alignment, so
519/// this method will assert on them.
520/// If @p RefAsPointee, references are treated like their underlying type
521/// (for alignof), else they're treated like pointers (for CodeGen).
522CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) {
523  unsigned Align = Target.getCharWidth();
524
525  if (const AlignedAttr* AA = D->getAttr<AlignedAttr>())
526    Align = std::max(Align, AA->getMaxAlignment());
527
528  if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
529    QualType T = VD->getType();
530    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
531      if (RefAsPointee)
532        T = RT->getPointeeType();
533      else
534        T = getPointerType(RT->getPointeeType());
535    }
536    if (!T->isIncompleteType() && !T->isFunctionType()) {
537      unsigned MinWidth = Target.getLargeArrayMinWidth();
538      unsigned ArrayAlign = Target.getLargeArrayAlign();
539      if (isa<VariableArrayType>(T) && MinWidth != 0)
540        Align = std::max(Align, ArrayAlign);
541      if (ConstantArrayType *CT = dyn_cast<ConstantArrayType>(T)) {
542        unsigned Size = getTypeSize(CT);
543        if (MinWidth != 0 && MinWidth <= Size)
544          Align = std::max(Align, ArrayAlign);
545      }
546      // Incomplete or function types default to 1.
547      while (isa<VariableArrayType>(T) || isa<IncompleteArrayType>(T))
548        T = cast<ArrayType>(T)->getElementType();
549
550      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
551    }
552    if (const FieldDecl *FD = dyn_cast<FieldDecl>(VD)) {
553      // In the case of a field in a packed struct, we want the minimum
554      // of the alignment of the field and the alignment of the struct.
555      Align = std::min(Align,
556        getPreferredTypeAlign(FD->getParent()->getTypeForDecl()));
557    }
558  }
559
560  return CharUnits::fromQuantity(Align / Target.getCharWidth());
561}
562
563std::pair<CharUnits, CharUnits>
564ASTContext::getTypeInfoInChars(const Type *T) {
565  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
566  return std::make_pair(CharUnits::fromQuantity(Info.first / getCharWidth()),
567                        CharUnits::fromQuantity(Info.second / getCharWidth()));
568}
569
570std::pair<CharUnits, CharUnits>
571ASTContext::getTypeInfoInChars(QualType T) {
572  return getTypeInfoInChars(T.getTypePtr());
573}
574
575/// getTypeSize - Return the size of the specified type, in bits.  This method
576/// does not work on incomplete types.
577///
578/// FIXME: Pointers into different addr spaces could have different sizes and
579/// alignment requirements: getPointerInfo should take an AddrSpace, this
580/// should take a QualType, &c.
581std::pair<uint64_t, unsigned>
582ASTContext::getTypeInfo(const Type *T) {
583  uint64_t Width=0;
584  unsigned Align=8;
585  switch (T->getTypeClass()) {
586#define TYPE(Class, Base)
587#define ABSTRACT_TYPE(Class, Base)
588#define NON_CANONICAL_TYPE(Class, Base)
589#define DEPENDENT_TYPE(Class, Base) case Type::Class:
590#include "clang/AST/TypeNodes.def"
591    assert(false && "Should not see dependent types");
592    break;
593
594  case Type::FunctionNoProto:
595  case Type::FunctionProto:
596    // GCC extension: alignof(function) = 32 bits
597    Width = 0;
598    Align = 32;
599    break;
600
601  case Type::IncompleteArray:
602  case Type::VariableArray:
603    Width = 0;
604    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
605    break;
606
607  case Type::ConstantArray: {
608    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
609
610    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
611    Width = EltInfo.first*CAT->getSize().getZExtValue();
612    Align = EltInfo.second;
613    break;
614  }
615  case Type::ExtVector:
616  case Type::Vector: {
617    const VectorType *VT = cast<VectorType>(T);
618    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
619    Width = EltInfo.first*VT->getNumElements();
620    Align = Width;
621    // If the alignment is not a power of 2, round up to the next power of 2.
622    // This happens for non-power-of-2 length vectors.
623    if (Align & (Align-1)) {
624      Align = llvm::NextPowerOf2(Align);
625      Width = llvm::RoundUpToAlignment(Width, Align);
626    }
627    break;
628  }
629
630  case Type::Builtin:
631    switch (cast<BuiltinType>(T)->getKind()) {
632    default: assert(0 && "Unknown builtin type!");
633    case BuiltinType::Void:
634      // GCC extension: alignof(void) = 8 bits.
635      Width = 0;
636      Align = 8;
637      break;
638
639    case BuiltinType::Bool:
640      Width = Target.getBoolWidth();
641      Align = Target.getBoolAlign();
642      break;
643    case BuiltinType::Char_S:
644    case BuiltinType::Char_U:
645    case BuiltinType::UChar:
646    case BuiltinType::SChar:
647      Width = Target.getCharWidth();
648      Align = Target.getCharAlign();
649      break;
650    case BuiltinType::WChar:
651      Width = Target.getWCharWidth();
652      Align = Target.getWCharAlign();
653      break;
654    case BuiltinType::Char16:
655      Width = Target.getChar16Width();
656      Align = Target.getChar16Align();
657      break;
658    case BuiltinType::Char32:
659      Width = Target.getChar32Width();
660      Align = Target.getChar32Align();
661      break;
662    case BuiltinType::UShort:
663    case BuiltinType::Short:
664      Width = Target.getShortWidth();
665      Align = Target.getShortAlign();
666      break;
667    case BuiltinType::UInt:
668    case BuiltinType::Int:
669      Width = Target.getIntWidth();
670      Align = Target.getIntAlign();
671      break;
672    case BuiltinType::ULong:
673    case BuiltinType::Long:
674      Width = Target.getLongWidth();
675      Align = Target.getLongAlign();
676      break;
677    case BuiltinType::ULongLong:
678    case BuiltinType::LongLong:
679      Width = Target.getLongLongWidth();
680      Align = Target.getLongLongAlign();
681      break;
682    case BuiltinType::Int128:
683    case BuiltinType::UInt128:
684      Width = 128;
685      Align = 128; // int128_t is 128-bit aligned on all targets.
686      break;
687    case BuiltinType::Float:
688      Width = Target.getFloatWidth();
689      Align = Target.getFloatAlign();
690      break;
691    case BuiltinType::Double:
692      Width = Target.getDoubleWidth();
693      Align = Target.getDoubleAlign();
694      break;
695    case BuiltinType::LongDouble:
696      Width = Target.getLongDoubleWidth();
697      Align = Target.getLongDoubleAlign();
698      break;
699    case BuiltinType::NullPtr:
700      Width = Target.getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
701      Align = Target.getPointerAlign(0); //   == sizeof(void*)
702      break;
703    }
704    break;
705  case Type::ObjCObjectPointer:
706    Width = Target.getPointerWidth(0);
707    Align = Target.getPointerAlign(0);
708    break;
709  case Type::BlockPointer: {
710    unsigned AS = cast<BlockPointerType>(T)->getPointeeType().getAddressSpace();
711    Width = Target.getPointerWidth(AS);
712    Align = Target.getPointerAlign(AS);
713    break;
714  }
715  case Type::LValueReference:
716  case Type::RValueReference: {
717    // alignof and sizeof should never enter this code path here, so we go
718    // the pointer route.
719    unsigned AS = cast<ReferenceType>(T)->getPointeeType().getAddressSpace();
720    Width = Target.getPointerWidth(AS);
721    Align = Target.getPointerAlign(AS);
722    break;
723  }
724  case Type::Pointer: {
725    unsigned AS = cast<PointerType>(T)->getPointeeType().getAddressSpace();
726    Width = Target.getPointerWidth(AS);
727    Align = Target.getPointerAlign(AS);
728    break;
729  }
730  case Type::MemberPointer: {
731    QualType Pointee = cast<MemberPointerType>(T)->getPointeeType();
732    std::pair<uint64_t, unsigned> PtrDiffInfo =
733      getTypeInfo(getPointerDiffType());
734    Width = PtrDiffInfo.first;
735    if (Pointee->isFunctionType())
736      Width *= 2;
737    Align = PtrDiffInfo.second;
738    break;
739  }
740  case Type::Complex: {
741    // Complex types have the same alignment as their elements, but twice the
742    // size.
743    std::pair<uint64_t, unsigned> EltInfo =
744      getTypeInfo(cast<ComplexType>(T)->getElementType());
745    Width = EltInfo.first*2;
746    Align = EltInfo.second;
747    break;
748  }
749  case Type::ObjCObject:
750    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
751  case Type::ObjCInterface: {
752    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
753    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
754    Width = Layout.getSize();
755    Align = Layout.getAlignment();
756    break;
757  }
758  case Type::Record:
759  case Type::Enum: {
760    const TagType *TT = cast<TagType>(T);
761
762    if (TT->getDecl()->isInvalidDecl()) {
763      Width = 1;
764      Align = 1;
765      break;
766    }
767
768    if (const EnumType *ET = dyn_cast<EnumType>(TT))
769      return getTypeInfo(ET->getDecl()->getIntegerType());
770
771    const RecordType *RT = cast<RecordType>(TT);
772    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
773    Width = Layout.getSize();
774    Align = Layout.getAlignment();
775    break;
776  }
777
778  case Type::SubstTemplateTypeParm:
779    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
780                       getReplacementType().getTypePtr());
781
782  case Type::Typedef: {
783    const TypedefDecl *Typedef = cast<TypedefType>(T)->getDecl();
784    if (const AlignedAttr *Aligned = Typedef->getAttr<AlignedAttr>()) {
785      Align = std::max(Aligned->getMaxAlignment(),
786                       getTypeAlign(Typedef->getUnderlyingType().getTypePtr()));
787      Width = getTypeSize(Typedef->getUnderlyingType().getTypePtr());
788    } else
789      return getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
790    break;
791  }
792
793  case Type::TypeOfExpr:
794    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
795                         .getTypePtr());
796
797  case Type::TypeOf:
798    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
799
800  case Type::Decltype:
801    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
802                        .getTypePtr());
803
804  case Type::Elaborated:
805    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
806
807  case Type::TemplateSpecialization:
808    assert(getCanonicalType(T) != T &&
809           "Cannot request the size of a dependent type");
810    // FIXME: this is likely to be wrong once we support template
811    // aliases, since a template alias could refer to a typedef that
812    // has an __aligned__ attribute on it.
813    return getTypeInfo(getCanonicalType(T));
814  }
815
816  assert(Align && (Align & (Align-1)) == 0 && "Alignment must be power of 2");
817  return std::make_pair(Width, Align);
818}
819
820/// getTypeSizeInChars - Return the size of the specified type, in characters.
821/// This method does not work on incomplete types.
822CharUnits ASTContext::getTypeSizeInChars(QualType T) {
823  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
824}
825CharUnits ASTContext::getTypeSizeInChars(const Type *T) {
826  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
827}
828
829/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
830/// characters. This method does not work on incomplete types.
831CharUnits ASTContext::getTypeAlignInChars(QualType T) {
832  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
833}
834CharUnits ASTContext::getTypeAlignInChars(const Type *T) {
835  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
836}
837
838/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
839/// type for the current target in bits.  This can be different than the ABI
840/// alignment in cases where it is beneficial for performance to overalign
841/// a data type.
842unsigned ASTContext::getPreferredTypeAlign(const Type *T) {
843  unsigned ABIAlign = getTypeAlign(T);
844
845  // Double and long long should be naturally aligned if possible.
846  if (const ComplexType* CT = T->getAs<ComplexType>())
847    T = CT->getElementType().getTypePtr();
848  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
849      T->isSpecificBuiltinType(BuiltinType::LongLong))
850    return std::max(ABIAlign, (unsigned)getTypeSize(T));
851
852  return ABIAlign;
853}
854
855static void CollectLocalObjCIvars(ASTContext *Ctx,
856                                  const ObjCInterfaceDecl *OI,
857                                  llvm::SmallVectorImpl<FieldDecl*> &Fields) {
858  for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
859       E = OI->ivar_end(); I != E; ++I) {
860    ObjCIvarDecl *IVDecl = *I;
861    if (!IVDecl->isInvalidDecl())
862      Fields.push_back(cast<FieldDecl>(IVDecl));
863  }
864}
865
866void ASTContext::CollectObjCIvars(const ObjCInterfaceDecl *OI,
867                             llvm::SmallVectorImpl<FieldDecl*> &Fields) {
868  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
869    CollectObjCIvars(SuperClass, Fields);
870  CollectLocalObjCIvars(this, OI, Fields);
871}
872
873/// ShallowCollectObjCIvars -
874/// Collect all ivars, including those synthesized, in the current class.
875///
876void ASTContext::ShallowCollectObjCIvars(const ObjCInterfaceDecl *OI,
877                                 llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
878  for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
879         E = OI->ivar_end(); I != E; ++I) {
880     Ivars.push_back(*I);
881  }
882
883  CollectNonClassIvars(OI, Ivars);
884}
885
886/// CollectNonClassIvars -
887/// This routine collects all other ivars which are not declared in the class.
888/// This includes synthesized ivars (via @synthesize) and those in
889//  class's @implementation.
890///
891void ASTContext::CollectNonClassIvars(const ObjCInterfaceDecl *OI,
892                                llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
893  // Find ivars declared in class extension.
894  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
895       CDecl = CDecl->getNextClassExtension()) {
896    for (ObjCCategoryDecl::ivar_iterator I = CDecl->ivar_begin(),
897         E = CDecl->ivar_end(); I != E; ++I) {
898      Ivars.push_back(*I);
899    }
900  }
901
902  // Also add any ivar defined in this class's implementation.  This
903  // includes synthesized ivars.
904  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation()) {
905    for (ObjCImplementationDecl::ivar_iterator I = ImplDecl->ivar_begin(),
906         E = ImplDecl->ivar_end(); I != E; ++I)
907      Ivars.push_back(*I);
908  }
909}
910
911/// CollectInheritedProtocols - Collect all protocols in current class and
912/// those inherited by it.
913void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
914                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
915  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
916    for (ObjCInterfaceDecl::protocol_iterator P = OI->protocol_begin(),
917         PE = OI->protocol_end(); P != PE; ++P) {
918      ObjCProtocolDecl *Proto = (*P);
919      Protocols.insert(Proto);
920      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
921           PE = Proto->protocol_end(); P != PE; ++P) {
922        Protocols.insert(*P);
923        CollectInheritedProtocols(*P, Protocols);
924      }
925    }
926
927    // Categories of this Interface.
928    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
929         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
930      CollectInheritedProtocols(CDeclChain, Protocols);
931    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
932      while (SD) {
933        CollectInheritedProtocols(SD, Protocols);
934        SD = SD->getSuperClass();
935      }
936  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
937    for (ObjCInterfaceDecl::protocol_iterator P = OC->protocol_begin(),
938         PE = OC->protocol_end(); P != PE; ++P) {
939      ObjCProtocolDecl *Proto = (*P);
940      Protocols.insert(Proto);
941      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
942           PE = Proto->protocol_end(); P != PE; ++P)
943        CollectInheritedProtocols(*P, Protocols);
944    }
945  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
946    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
947         PE = OP->protocol_end(); P != PE; ++P) {
948      ObjCProtocolDecl *Proto = (*P);
949      Protocols.insert(Proto);
950      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
951           PE = Proto->protocol_end(); P != PE; ++P)
952        CollectInheritedProtocols(*P, Protocols);
953    }
954  }
955}
956
957unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) {
958  unsigned count = 0;
959  // Count ivars declared in class extension.
960  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
961       CDecl = CDecl->getNextClassExtension())
962    count += CDecl->ivar_size();
963
964  // Count ivar defined in this class's implementation.  This
965  // includes synthesized ivars.
966  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
967    count += ImplDecl->ivar_size();
968
969  return count;
970}
971
972/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
973ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
974  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
975    I = ObjCImpls.find(D);
976  if (I != ObjCImpls.end())
977    return cast<ObjCImplementationDecl>(I->second);
978  return 0;
979}
980/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
981ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
982  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
983    I = ObjCImpls.find(D);
984  if (I != ObjCImpls.end())
985    return cast<ObjCCategoryImplDecl>(I->second);
986  return 0;
987}
988
989/// \brief Set the implementation of ObjCInterfaceDecl.
990void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
991                           ObjCImplementationDecl *ImplD) {
992  assert(IFaceD && ImplD && "Passed null params");
993  ObjCImpls[IFaceD] = ImplD;
994}
995/// \brief Set the implementation of ObjCCategoryDecl.
996void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
997                           ObjCCategoryImplDecl *ImplD) {
998  assert(CatD && ImplD && "Passed null params");
999  ObjCImpls[CatD] = ImplD;
1000}
1001
1002/// \brief Allocate an uninitialized TypeSourceInfo.
1003///
1004/// The caller should initialize the memory held by TypeSourceInfo using
1005/// the TypeLoc wrappers.
1006///
1007/// \param T the type that will be the basis for type source info. This type
1008/// should refer to how the declarator was written in source code, not to
1009/// what type semantic analysis resolved the declarator to.
1010TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1011                                                 unsigned DataSize) {
1012  if (!DataSize)
1013    DataSize = TypeLoc::getFullDataSizeForType(T);
1014  else
1015    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1016           "incorrect data size provided to CreateTypeSourceInfo!");
1017
1018  TypeSourceInfo *TInfo =
1019    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1020  new (TInfo) TypeSourceInfo(T);
1021  return TInfo;
1022}
1023
1024TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1025                                                     SourceLocation L) {
1026  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1027  DI->getTypeLoc().initialize(L);
1028  return DI;
1029}
1030
1031const ASTRecordLayout &
1032ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) {
1033  return getObjCLayout(D, 0);
1034}
1035
1036const ASTRecordLayout &
1037ASTContext::getASTObjCImplementationLayout(const ObjCImplementationDecl *D) {
1038  return getObjCLayout(D->getClassInterface(), D);
1039}
1040
1041//===----------------------------------------------------------------------===//
1042//                   Type creation/memoization methods
1043//===----------------------------------------------------------------------===//
1044
1045QualType ASTContext::getExtQualType(const Type *TypeNode, Qualifiers Quals) {
1046  unsigned Fast = Quals.getFastQualifiers();
1047  Quals.removeFastQualifiers();
1048
1049  // Check if we've already instantiated this type.
1050  llvm::FoldingSetNodeID ID;
1051  ExtQuals::Profile(ID, TypeNode, Quals);
1052  void *InsertPos = 0;
1053  if (ExtQuals *EQ = ExtQualNodes.FindNodeOrInsertPos(ID, InsertPos)) {
1054    assert(EQ->getQualifiers() == Quals);
1055    QualType T = QualType(EQ, Fast);
1056    return T;
1057  }
1058
1059  ExtQuals *New = new (*this, TypeAlignment) ExtQuals(*this, TypeNode, Quals);
1060  ExtQualNodes.InsertNode(New, InsertPos);
1061  QualType T = QualType(New, Fast);
1062  return T;
1063}
1064
1065QualType ASTContext::getVolatileType(QualType T) {
1066  QualType CanT = getCanonicalType(T);
1067  if (CanT.isVolatileQualified()) return T;
1068
1069  QualifierCollector Quals;
1070  const Type *TypeNode = Quals.strip(T);
1071  Quals.addVolatile();
1072
1073  return getExtQualType(TypeNode, Quals);
1074}
1075
1076QualType ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) {
1077  QualType CanT = getCanonicalType(T);
1078  if (CanT.getAddressSpace() == AddressSpace)
1079    return T;
1080
1081  // If we are composing extended qualifiers together, merge together
1082  // into one ExtQuals node.
1083  QualifierCollector Quals;
1084  const Type *TypeNode = Quals.strip(T);
1085
1086  // If this type already has an address space specified, it cannot get
1087  // another one.
1088  assert(!Quals.hasAddressSpace() &&
1089         "Type cannot be in multiple addr spaces!");
1090  Quals.addAddressSpace(AddressSpace);
1091
1092  return getExtQualType(TypeNode, Quals);
1093}
1094
1095QualType ASTContext::getObjCGCQualType(QualType T,
1096                                       Qualifiers::GC GCAttr) {
1097  QualType CanT = getCanonicalType(T);
1098  if (CanT.getObjCGCAttr() == GCAttr)
1099    return T;
1100
1101  if (T->isPointerType()) {
1102    QualType Pointee = T->getAs<PointerType>()->getPointeeType();
1103    if (Pointee->isAnyPointerType()) {
1104      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1105      return getPointerType(ResultType);
1106    }
1107  }
1108
1109  // If we are composing extended qualifiers together, merge together
1110  // into one ExtQuals node.
1111  QualifierCollector Quals;
1112  const Type *TypeNode = Quals.strip(T);
1113
1114  // If this type already has an ObjCGC specified, it cannot get
1115  // another one.
1116  assert(!Quals.hasObjCGCAttr() &&
1117         "Type cannot have multiple ObjCGCs!");
1118  Quals.addObjCGCAttr(GCAttr);
1119
1120  return getExtQualType(TypeNode, Quals);
1121}
1122
1123static QualType getExtFunctionType(ASTContext& Context, QualType T,
1124                                        const FunctionType::ExtInfo &Info) {
1125  QualType ResultType;
1126  if (const PointerType *Pointer = T->getAs<PointerType>()) {
1127    QualType Pointee = Pointer->getPointeeType();
1128    ResultType = getExtFunctionType(Context, Pointee, Info);
1129    if (ResultType == Pointee)
1130      return T;
1131
1132    ResultType = Context.getPointerType(ResultType);
1133  } else if (const BlockPointerType *BlockPointer
1134                                              = T->getAs<BlockPointerType>()) {
1135    QualType Pointee = BlockPointer->getPointeeType();
1136    ResultType = getExtFunctionType(Context, Pointee, Info);
1137    if (ResultType == Pointee)
1138      return T;
1139
1140    ResultType = Context.getBlockPointerType(ResultType);
1141   } else if (const FunctionType *F = T->getAs<FunctionType>()) {
1142    if (F->getExtInfo() == Info)
1143      return T;
1144
1145    if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(F)) {
1146      ResultType = Context.getFunctionNoProtoType(FNPT->getResultType(),
1147                                                  Info);
1148    } else {
1149      const FunctionProtoType *FPT = cast<FunctionProtoType>(F);
1150      ResultType
1151        = Context.getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1152                                  FPT->getNumArgs(), FPT->isVariadic(),
1153                                  FPT->getTypeQuals(),
1154                                  FPT->hasExceptionSpec(),
1155                                  FPT->hasAnyExceptionSpec(),
1156                                  FPT->getNumExceptions(),
1157                                  FPT->exception_begin(),
1158                                  Info);
1159    }
1160  } else
1161    return T;
1162
1163  return Context.getQualifiedType(ResultType, T.getLocalQualifiers());
1164}
1165
1166QualType ASTContext::getNoReturnType(QualType T, bool AddNoReturn) {
1167  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1168  return getExtFunctionType(*this, T,
1169                                 Info.withNoReturn(AddNoReturn));
1170}
1171
1172QualType ASTContext::getCallConvType(QualType T, CallingConv CallConv) {
1173  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1174  return getExtFunctionType(*this, T,
1175                            Info.withCallingConv(CallConv));
1176}
1177
1178QualType ASTContext::getRegParmType(QualType T, unsigned RegParm) {
1179  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1180  return getExtFunctionType(*this, T,
1181                                 Info.withRegParm(RegParm));
1182}
1183
1184/// getComplexType - Return the uniqued reference to the type for a complex
1185/// number with the specified element type.
1186QualType ASTContext::getComplexType(QualType T) {
1187  // Unique pointers, to guarantee there is only one pointer of a particular
1188  // structure.
1189  llvm::FoldingSetNodeID ID;
1190  ComplexType::Profile(ID, T);
1191
1192  void *InsertPos = 0;
1193  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1194    return QualType(CT, 0);
1195
1196  // If the pointee type isn't canonical, this won't be a canonical type either,
1197  // so fill in the canonical type field.
1198  QualType Canonical;
1199  if (!T.isCanonical()) {
1200    Canonical = getComplexType(getCanonicalType(T));
1201
1202    // Get the new insert position for the node we care about.
1203    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1204    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1205  }
1206  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1207  Types.push_back(New);
1208  ComplexTypes.InsertNode(New, InsertPos);
1209  return QualType(New, 0);
1210}
1211
1212/// getPointerType - Return the uniqued reference to the type for a pointer to
1213/// the specified type.
1214QualType ASTContext::getPointerType(QualType T) {
1215  // Unique pointers, to guarantee there is only one pointer of a particular
1216  // structure.
1217  llvm::FoldingSetNodeID ID;
1218  PointerType::Profile(ID, T);
1219
1220  void *InsertPos = 0;
1221  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1222    return QualType(PT, 0);
1223
1224  // If the pointee type isn't canonical, this won't be a canonical type either,
1225  // so fill in the canonical type field.
1226  QualType Canonical;
1227  if (!T.isCanonical()) {
1228    Canonical = getPointerType(getCanonicalType(T));
1229
1230    // Get the new insert position for the node we care about.
1231    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1232    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1233  }
1234  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1235  Types.push_back(New);
1236  PointerTypes.InsertNode(New, InsertPos);
1237  return QualType(New, 0);
1238}
1239
1240/// getBlockPointerType - Return the uniqued reference to the type for
1241/// a pointer to the specified block.
1242QualType ASTContext::getBlockPointerType(QualType T) {
1243  assert(T->isFunctionType() && "block of function types only");
1244  // Unique pointers, to guarantee there is only one block of a particular
1245  // structure.
1246  llvm::FoldingSetNodeID ID;
1247  BlockPointerType::Profile(ID, T);
1248
1249  void *InsertPos = 0;
1250  if (BlockPointerType *PT =
1251        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1252    return QualType(PT, 0);
1253
1254  // If the block pointee type isn't canonical, this won't be a canonical
1255  // type either so fill in the canonical type field.
1256  QualType Canonical;
1257  if (!T.isCanonical()) {
1258    Canonical = getBlockPointerType(getCanonicalType(T));
1259
1260    // Get the new insert position for the node we care about.
1261    BlockPointerType *NewIP =
1262      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1263    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1264  }
1265  BlockPointerType *New
1266    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1267  Types.push_back(New);
1268  BlockPointerTypes.InsertNode(New, InsertPos);
1269  return QualType(New, 0);
1270}
1271
1272/// getLValueReferenceType - Return the uniqued reference to the type for an
1273/// lvalue reference to the specified type.
1274QualType ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) {
1275  // Unique pointers, to guarantee there is only one pointer of a particular
1276  // structure.
1277  llvm::FoldingSetNodeID ID;
1278  ReferenceType::Profile(ID, T, SpelledAsLValue);
1279
1280  void *InsertPos = 0;
1281  if (LValueReferenceType *RT =
1282        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1283    return QualType(RT, 0);
1284
1285  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1286
1287  // If the referencee type isn't canonical, this won't be a canonical type
1288  // either, so fill in the canonical type field.
1289  QualType Canonical;
1290  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1291    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1292    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1293
1294    // Get the new insert position for the node we care about.
1295    LValueReferenceType *NewIP =
1296      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1297    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1298  }
1299
1300  LValueReferenceType *New
1301    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1302                                                     SpelledAsLValue);
1303  Types.push_back(New);
1304  LValueReferenceTypes.InsertNode(New, InsertPos);
1305
1306  return QualType(New, 0);
1307}
1308
1309/// getRValueReferenceType - Return the uniqued reference to the type for an
1310/// rvalue reference to the specified type.
1311QualType ASTContext::getRValueReferenceType(QualType T) {
1312  // Unique pointers, to guarantee there is only one pointer of a particular
1313  // structure.
1314  llvm::FoldingSetNodeID ID;
1315  ReferenceType::Profile(ID, T, false);
1316
1317  void *InsertPos = 0;
1318  if (RValueReferenceType *RT =
1319        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1320    return QualType(RT, 0);
1321
1322  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1323
1324  // If the referencee type isn't canonical, this won't be a canonical type
1325  // either, so fill in the canonical type field.
1326  QualType Canonical;
1327  if (InnerRef || !T.isCanonical()) {
1328    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1329    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1330
1331    // Get the new insert position for the node we care about.
1332    RValueReferenceType *NewIP =
1333      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1334    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1335  }
1336
1337  RValueReferenceType *New
1338    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1339  Types.push_back(New);
1340  RValueReferenceTypes.InsertNode(New, InsertPos);
1341  return QualType(New, 0);
1342}
1343
1344/// getMemberPointerType - Return the uniqued reference to the type for a
1345/// member pointer to the specified type, in the specified class.
1346QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) {
1347  // Unique pointers, to guarantee there is only one pointer of a particular
1348  // structure.
1349  llvm::FoldingSetNodeID ID;
1350  MemberPointerType::Profile(ID, T, Cls);
1351
1352  void *InsertPos = 0;
1353  if (MemberPointerType *PT =
1354      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1355    return QualType(PT, 0);
1356
1357  // If the pointee or class type isn't canonical, this won't be a canonical
1358  // type either, so fill in the canonical type field.
1359  QualType Canonical;
1360  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1361    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1362
1363    // Get the new insert position for the node we care about.
1364    MemberPointerType *NewIP =
1365      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1366    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1367  }
1368  MemberPointerType *New
1369    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1370  Types.push_back(New);
1371  MemberPointerTypes.InsertNode(New, InsertPos);
1372  return QualType(New, 0);
1373}
1374
1375/// getConstantArrayType - Return the unique reference to the type for an
1376/// array of the specified element type.
1377QualType ASTContext::getConstantArrayType(QualType EltTy,
1378                                          const llvm::APInt &ArySizeIn,
1379                                          ArrayType::ArraySizeModifier ASM,
1380                                          unsigned EltTypeQuals) {
1381  assert((EltTy->isDependentType() ||
1382          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1383         "Constant array of VLAs is illegal!");
1384
1385  // Convert the array size into a canonical width matching the pointer size for
1386  // the target.
1387  llvm::APInt ArySize(ArySizeIn);
1388  ArySize.zextOrTrunc(Target.getPointerWidth(EltTy.getAddressSpace()));
1389
1390  llvm::FoldingSetNodeID ID;
1391  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, EltTypeQuals);
1392
1393  void *InsertPos = 0;
1394  if (ConstantArrayType *ATP =
1395      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1396    return QualType(ATP, 0);
1397
1398  // If the element type isn't canonical, this won't be a canonical type either,
1399  // so fill in the canonical type field.
1400  QualType Canonical;
1401  if (!EltTy.isCanonical()) {
1402    Canonical = getConstantArrayType(getCanonicalType(EltTy), ArySize,
1403                                     ASM, EltTypeQuals);
1404    // Get the new insert position for the node we care about.
1405    ConstantArrayType *NewIP =
1406      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1407    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1408  }
1409
1410  ConstantArrayType *New = new(*this,TypeAlignment)
1411    ConstantArrayType(EltTy, Canonical, ArySize, ASM, EltTypeQuals);
1412  ConstantArrayTypes.InsertNode(New, InsertPos);
1413  Types.push_back(New);
1414  return QualType(New, 0);
1415}
1416
1417/// getVariableArrayType - Returns a non-unique reference to the type for a
1418/// variable array of the specified element type.
1419QualType ASTContext::getVariableArrayType(QualType EltTy,
1420                                          Expr *NumElts,
1421                                          ArrayType::ArraySizeModifier ASM,
1422                                          unsigned EltTypeQuals,
1423                                          SourceRange Brackets) {
1424  // Since we don't unique expressions, it isn't possible to unique VLA's
1425  // that have an expression provided for their size.
1426  QualType CanonType;
1427
1428  if (!EltTy.isCanonical()) {
1429    if (NumElts)
1430      NumElts->Retain();
1431    CanonType = getVariableArrayType(getCanonicalType(EltTy), NumElts, ASM,
1432                                     EltTypeQuals, Brackets);
1433  }
1434
1435  VariableArrayType *New = new(*this, TypeAlignment)
1436    VariableArrayType(EltTy, CanonType, NumElts, ASM, EltTypeQuals, Brackets);
1437
1438  VariableArrayTypes.push_back(New);
1439  Types.push_back(New);
1440  return QualType(New, 0);
1441}
1442
1443/// getDependentSizedArrayType - Returns a non-unique reference to
1444/// the type for a dependently-sized array of the specified element
1445/// type.
1446QualType ASTContext::getDependentSizedArrayType(QualType EltTy,
1447                                                Expr *NumElts,
1448                                                ArrayType::ArraySizeModifier ASM,
1449                                                unsigned EltTypeQuals,
1450                                                SourceRange Brackets) {
1451  assert((!NumElts || NumElts->isTypeDependent() ||
1452          NumElts->isValueDependent()) &&
1453         "Size must be type- or value-dependent!");
1454
1455  void *InsertPos = 0;
1456  DependentSizedArrayType *Canon = 0;
1457  llvm::FoldingSetNodeID ID;
1458
1459  if (NumElts) {
1460    // Dependently-sized array types that do not have a specified
1461    // number of elements will have their sizes deduced from an
1462    // initializer.
1463    DependentSizedArrayType::Profile(ID, *this, getCanonicalType(EltTy), ASM,
1464                                     EltTypeQuals, NumElts);
1465
1466    Canon = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1467  }
1468
1469  DependentSizedArrayType *New;
1470  if (Canon) {
1471    // We already have a canonical version of this array type; use it as
1472    // the canonical type for a newly-built type.
1473    New = new (*this, TypeAlignment)
1474      DependentSizedArrayType(*this, EltTy, QualType(Canon, 0),
1475                              NumElts, ASM, EltTypeQuals, Brackets);
1476  } else {
1477    QualType CanonEltTy = getCanonicalType(EltTy);
1478    if (CanonEltTy == EltTy) {
1479      New = new (*this, TypeAlignment)
1480        DependentSizedArrayType(*this, EltTy, QualType(),
1481                                NumElts, ASM, EltTypeQuals, Brackets);
1482
1483      if (NumElts) {
1484        DependentSizedArrayType *CanonCheck
1485          = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1486        assert(!CanonCheck && "Dependent-sized canonical array type broken");
1487        (void)CanonCheck;
1488        DependentSizedArrayTypes.InsertNode(New, InsertPos);
1489      }
1490    } else {
1491      QualType Canon = getDependentSizedArrayType(CanonEltTy, NumElts,
1492                                                  ASM, EltTypeQuals,
1493                                                  SourceRange());
1494      New = new (*this, TypeAlignment)
1495        DependentSizedArrayType(*this, EltTy, Canon,
1496                                NumElts, ASM, EltTypeQuals, Brackets);
1497    }
1498  }
1499
1500  Types.push_back(New);
1501  return QualType(New, 0);
1502}
1503
1504QualType ASTContext::getIncompleteArrayType(QualType EltTy,
1505                                            ArrayType::ArraySizeModifier ASM,
1506                                            unsigned EltTypeQuals) {
1507  llvm::FoldingSetNodeID ID;
1508  IncompleteArrayType::Profile(ID, EltTy, ASM, EltTypeQuals);
1509
1510  void *InsertPos = 0;
1511  if (IncompleteArrayType *ATP =
1512       IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1513    return QualType(ATP, 0);
1514
1515  // If the element type isn't canonical, this won't be a canonical type
1516  // either, so fill in the canonical type field.
1517  QualType Canonical;
1518
1519  if (!EltTy.isCanonical()) {
1520    Canonical = getIncompleteArrayType(getCanonicalType(EltTy),
1521                                       ASM, EltTypeQuals);
1522
1523    // Get the new insert position for the node we care about.
1524    IncompleteArrayType *NewIP =
1525      IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1526    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1527  }
1528
1529  IncompleteArrayType *New = new (*this, TypeAlignment)
1530    IncompleteArrayType(EltTy, Canonical, ASM, EltTypeQuals);
1531
1532  IncompleteArrayTypes.InsertNode(New, InsertPos);
1533  Types.push_back(New);
1534  return QualType(New, 0);
1535}
1536
1537/// getVectorType - Return the unique reference to a vector type of
1538/// the specified element type and size. VectorType must be a built-in type.
1539QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1540    VectorType::AltiVecSpecific AltiVecSpec) {
1541  BuiltinType *baseType;
1542
1543  baseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1544  assert(baseType != 0 && "getVectorType(): Expecting a built-in type");
1545
1546  // Check if we've already instantiated a vector of this type.
1547  llvm::FoldingSetNodeID ID;
1548  VectorType::Profile(ID, vecType, NumElts, Type::Vector, AltiVecSpec);
1549
1550  void *InsertPos = 0;
1551  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1552    return QualType(VTP, 0);
1553
1554  // If the element type isn't canonical, this won't be a canonical type either,
1555  // so fill in the canonical type field.
1556  QualType Canonical;
1557  if (!vecType.isCanonical() || (AltiVecSpec == VectorType::AltiVec)) {
1558    // pass VectorType::NotAltiVec for AltiVecSpec to make AltiVec canonical
1559    // vector type (except 'vector bool ...' and 'vector Pixel') the same as
1560    // the equivalent GCC vector types
1561    Canonical = getVectorType(getCanonicalType(vecType), NumElts,
1562      VectorType::NotAltiVec);
1563
1564    // Get the new insert position for the node we care about.
1565    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1566    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1567  }
1568  VectorType *New = new (*this, TypeAlignment)
1569    VectorType(vecType, NumElts, Canonical, AltiVecSpec);
1570  VectorTypes.InsertNode(New, InsertPos);
1571  Types.push_back(New);
1572  return QualType(New, 0);
1573}
1574
1575/// getExtVectorType - Return the unique reference to an extended vector type of
1576/// the specified element type and size. VectorType must be a built-in type.
1577QualType ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) {
1578  BuiltinType *baseType;
1579
1580  baseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1581  assert(baseType != 0 && "getExtVectorType(): Expecting a built-in type");
1582
1583  // Check if we've already instantiated a vector of this type.
1584  llvm::FoldingSetNodeID ID;
1585  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1586                      VectorType::NotAltiVec);
1587  void *InsertPos = 0;
1588  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1589    return QualType(VTP, 0);
1590
1591  // If the element type isn't canonical, this won't be a canonical type either,
1592  // so fill in the canonical type field.
1593  QualType Canonical;
1594  if (!vecType.isCanonical()) {
1595    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
1596
1597    // Get the new insert position for the node we care about.
1598    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1599    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1600  }
1601  ExtVectorType *New = new (*this, TypeAlignment)
1602    ExtVectorType(vecType, NumElts, Canonical);
1603  VectorTypes.InsertNode(New, InsertPos);
1604  Types.push_back(New);
1605  return QualType(New, 0);
1606}
1607
1608QualType ASTContext::getDependentSizedExtVectorType(QualType vecType,
1609                                                    Expr *SizeExpr,
1610                                                    SourceLocation AttrLoc) {
1611  llvm::FoldingSetNodeID ID;
1612  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
1613                                       SizeExpr);
1614
1615  void *InsertPos = 0;
1616  DependentSizedExtVectorType *Canon
1617    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1618  DependentSizedExtVectorType *New;
1619  if (Canon) {
1620    // We already have a canonical version of this array type; use it as
1621    // the canonical type for a newly-built type.
1622    New = new (*this, TypeAlignment)
1623      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
1624                                  SizeExpr, AttrLoc);
1625  } else {
1626    QualType CanonVecTy = getCanonicalType(vecType);
1627    if (CanonVecTy == vecType) {
1628      New = new (*this, TypeAlignment)
1629        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
1630                                    AttrLoc);
1631
1632      DependentSizedExtVectorType *CanonCheck
1633        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1634      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
1635      (void)CanonCheck;
1636      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
1637    } else {
1638      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
1639                                                      SourceLocation());
1640      New = new (*this, TypeAlignment)
1641        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
1642    }
1643  }
1644
1645  Types.push_back(New);
1646  return QualType(New, 0);
1647}
1648
1649/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
1650///
1651QualType ASTContext::getFunctionNoProtoType(QualType ResultTy,
1652                                            const FunctionType::ExtInfo &Info) {
1653  const CallingConv CallConv = Info.getCC();
1654  // Unique functions, to guarantee there is only one function of a particular
1655  // structure.
1656  llvm::FoldingSetNodeID ID;
1657  FunctionNoProtoType::Profile(ID, ResultTy, Info);
1658
1659  void *InsertPos = 0;
1660  if (FunctionNoProtoType *FT =
1661        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1662    return QualType(FT, 0);
1663
1664  QualType Canonical;
1665  if (!ResultTy.isCanonical() ||
1666      getCanonicalCallConv(CallConv) != CallConv) {
1667    Canonical =
1668      getFunctionNoProtoType(getCanonicalType(ResultTy),
1669                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1670
1671    // Get the new insert position for the node we care about.
1672    FunctionNoProtoType *NewIP =
1673      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1674    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1675  }
1676
1677  FunctionNoProtoType *New = new (*this, TypeAlignment)
1678    FunctionNoProtoType(ResultTy, Canonical, Info);
1679  Types.push_back(New);
1680  FunctionNoProtoTypes.InsertNode(New, InsertPos);
1681  return QualType(New, 0);
1682}
1683
1684/// getFunctionType - Return a normal function type with a typed argument
1685/// list.  isVariadic indicates whether the argument list includes '...'.
1686QualType ASTContext::getFunctionType(QualType ResultTy,const QualType *ArgArray,
1687                                     unsigned NumArgs, bool isVariadic,
1688                                     unsigned TypeQuals, bool hasExceptionSpec,
1689                                     bool hasAnyExceptionSpec, unsigned NumExs,
1690                                     const QualType *ExArray,
1691                                     const FunctionType::ExtInfo &Info) {
1692  const CallingConv CallConv= Info.getCC();
1693  // Unique functions, to guarantee there is only one function of a particular
1694  // structure.
1695  llvm::FoldingSetNodeID ID;
1696  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, isVariadic,
1697                             TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1698                             NumExs, ExArray, Info);
1699
1700  void *InsertPos = 0;
1701  if (FunctionProtoType *FTP =
1702        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1703    return QualType(FTP, 0);
1704
1705  // Determine whether the type being created is already canonical or not.
1706  bool isCanonical = !hasExceptionSpec && ResultTy.isCanonical();
1707  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
1708    if (!ArgArray[i].isCanonicalAsParam())
1709      isCanonical = false;
1710
1711  // If this type isn't canonical, get the canonical version of it.
1712  // The exception spec is not part of the canonical type.
1713  QualType Canonical;
1714  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
1715    llvm::SmallVector<QualType, 16> CanonicalArgs;
1716    CanonicalArgs.reserve(NumArgs);
1717    for (unsigned i = 0; i != NumArgs; ++i)
1718      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
1719
1720    Canonical = getFunctionType(getCanonicalType(ResultTy),
1721                                CanonicalArgs.data(), NumArgs,
1722                                isVariadic, TypeQuals, false,
1723                                false, 0, 0,
1724                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1725
1726    // Get the new insert position for the node we care about.
1727    FunctionProtoType *NewIP =
1728      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1729    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1730  }
1731
1732  // FunctionProtoType objects are allocated with extra bytes after them
1733  // for two variable size arrays (for parameter and exception types) at the
1734  // end of them.
1735  FunctionProtoType *FTP =
1736    (FunctionProtoType*)Allocate(sizeof(FunctionProtoType) +
1737                                 NumArgs*sizeof(QualType) +
1738                                 NumExs*sizeof(QualType), TypeAlignment);
1739  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, isVariadic,
1740                              TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1741                              ExArray, NumExs, Canonical, Info);
1742  Types.push_back(FTP);
1743  FunctionProtoTypes.InsertNode(FTP, InsertPos);
1744  return QualType(FTP, 0);
1745}
1746
1747#ifndef NDEBUG
1748static bool NeedsInjectedClassNameType(const RecordDecl *D) {
1749  if (!isa<CXXRecordDecl>(D)) return false;
1750  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
1751  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
1752    return true;
1753  if (RD->getDescribedClassTemplate() &&
1754      !isa<ClassTemplateSpecializationDecl>(RD))
1755    return true;
1756  return false;
1757}
1758#endif
1759
1760/// getInjectedClassNameType - Return the unique reference to the
1761/// injected class name type for the specified templated declaration.
1762QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
1763                                              QualType TST) {
1764  assert(NeedsInjectedClassNameType(Decl));
1765  if (Decl->TypeForDecl) {
1766    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1767  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDeclaration()) {
1768    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
1769    Decl->TypeForDecl = PrevDecl->TypeForDecl;
1770    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1771  } else {
1772    Decl->TypeForDecl =
1773      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
1774    Types.push_back(Decl->TypeForDecl);
1775  }
1776  return QualType(Decl->TypeForDecl, 0);
1777}
1778
1779/// getTypeDeclType - Return the unique reference to the type for the
1780/// specified type declaration.
1781QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) {
1782  assert(Decl && "Passed null for Decl param");
1783  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
1784
1785  if (const TypedefDecl *Typedef = dyn_cast<TypedefDecl>(Decl))
1786    return getTypedefType(Typedef);
1787
1788  assert(!isa<TemplateTypeParmDecl>(Decl) &&
1789         "Template type parameter types are always available.");
1790
1791  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
1792    assert(!Record->getPreviousDeclaration() &&
1793           "struct/union has previous declaration");
1794    assert(!NeedsInjectedClassNameType(Record));
1795    Decl->TypeForDecl = new (*this, TypeAlignment) RecordType(Record);
1796  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
1797    assert(!Enum->getPreviousDeclaration() &&
1798           "enum has previous declaration");
1799    Decl->TypeForDecl = new (*this, TypeAlignment) EnumType(Enum);
1800  } else if (const UnresolvedUsingTypenameDecl *Using =
1801               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
1802    Decl->TypeForDecl = new (*this, TypeAlignment) UnresolvedUsingType(Using);
1803  } else
1804    llvm_unreachable("TypeDecl without a type?");
1805
1806  Types.push_back(Decl->TypeForDecl);
1807  return QualType(Decl->TypeForDecl, 0);
1808}
1809
1810/// getTypedefType - Return the unique reference to the type for the
1811/// specified typename decl.
1812QualType
1813ASTContext::getTypedefType(const TypedefDecl *Decl, QualType Canonical) {
1814  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1815
1816  if (Canonical.isNull())
1817    Canonical = getCanonicalType(Decl->getUnderlyingType());
1818  Decl->TypeForDecl = new(*this, TypeAlignment)
1819    TypedefType(Type::Typedef, Decl, Canonical);
1820  Types.push_back(Decl->TypeForDecl);
1821  return QualType(Decl->TypeForDecl, 0);
1822}
1823
1824/// \brief Retrieve a substitution-result type.
1825QualType
1826ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
1827                                         QualType Replacement) {
1828  assert(Replacement.isCanonical()
1829         && "replacement types must always be canonical");
1830
1831  llvm::FoldingSetNodeID ID;
1832  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
1833  void *InsertPos = 0;
1834  SubstTemplateTypeParmType *SubstParm
1835    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1836
1837  if (!SubstParm) {
1838    SubstParm = new (*this, TypeAlignment)
1839      SubstTemplateTypeParmType(Parm, Replacement);
1840    Types.push_back(SubstParm);
1841    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
1842  }
1843
1844  return QualType(SubstParm, 0);
1845}
1846
1847/// \brief Retrieve the template type parameter type for a template
1848/// parameter or parameter pack with the given depth, index, and (optionally)
1849/// name.
1850QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
1851                                             bool ParameterPack,
1852                                             IdentifierInfo *Name) {
1853  llvm::FoldingSetNodeID ID;
1854  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, Name);
1855  void *InsertPos = 0;
1856  TemplateTypeParmType *TypeParm
1857    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1858
1859  if (TypeParm)
1860    return QualType(TypeParm, 0);
1861
1862  if (Name) {
1863    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
1864    TypeParm = new (*this, TypeAlignment)
1865      TemplateTypeParmType(Depth, Index, ParameterPack, Name, Canon);
1866
1867    TemplateTypeParmType *TypeCheck
1868      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1869    assert(!TypeCheck && "Template type parameter canonical type broken");
1870    (void)TypeCheck;
1871  } else
1872    TypeParm = new (*this, TypeAlignment)
1873      TemplateTypeParmType(Depth, Index, ParameterPack);
1874
1875  Types.push_back(TypeParm);
1876  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
1877
1878  return QualType(TypeParm, 0);
1879}
1880
1881TypeSourceInfo *
1882ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
1883                                              SourceLocation NameLoc,
1884                                        const TemplateArgumentListInfo &Args,
1885                                              QualType CanonType) {
1886  QualType TST = getTemplateSpecializationType(Name, Args, CanonType);
1887
1888  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
1889  TemplateSpecializationTypeLoc TL
1890    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
1891  TL.setTemplateNameLoc(NameLoc);
1892  TL.setLAngleLoc(Args.getLAngleLoc());
1893  TL.setRAngleLoc(Args.getRAngleLoc());
1894  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
1895    TL.setArgLocInfo(i, Args[i].getLocInfo());
1896  return DI;
1897}
1898
1899QualType
1900ASTContext::getTemplateSpecializationType(TemplateName Template,
1901                                          const TemplateArgumentListInfo &Args,
1902                                          QualType Canon) {
1903  unsigned NumArgs = Args.size();
1904
1905  llvm::SmallVector<TemplateArgument, 4> ArgVec;
1906  ArgVec.reserve(NumArgs);
1907  for (unsigned i = 0; i != NumArgs; ++i)
1908    ArgVec.push_back(Args[i].getArgument());
1909
1910  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
1911                                       Canon);
1912}
1913
1914QualType
1915ASTContext::getTemplateSpecializationType(TemplateName Template,
1916                                          const TemplateArgument *Args,
1917                                          unsigned NumArgs,
1918                                          QualType Canon) {
1919  if (!Canon.isNull())
1920    Canon = getCanonicalType(Canon);
1921  else
1922    Canon = getCanonicalTemplateSpecializationType(Template, Args, NumArgs);
1923
1924  // Allocate the (non-canonical) template specialization type, but don't
1925  // try to unique it: these types typically have location information that
1926  // we don't unique and don't want to lose.
1927  void *Mem = Allocate((sizeof(TemplateSpecializationType) +
1928                        sizeof(TemplateArgument) * NumArgs),
1929                       TypeAlignment);
1930  TemplateSpecializationType *Spec
1931    = new (Mem) TemplateSpecializationType(Template,
1932                                           Args, NumArgs,
1933                                           Canon);
1934
1935  Types.push_back(Spec);
1936  return QualType(Spec, 0);
1937}
1938
1939QualType
1940ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
1941                                                   const TemplateArgument *Args,
1942                                                   unsigned NumArgs) {
1943  // Build the canonical template specialization type.
1944  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
1945  llvm::SmallVector<TemplateArgument, 4> CanonArgs;
1946  CanonArgs.reserve(NumArgs);
1947  for (unsigned I = 0; I != NumArgs; ++I)
1948    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
1949
1950  // Determine whether this canonical template specialization type already
1951  // exists.
1952  llvm::FoldingSetNodeID ID;
1953  TemplateSpecializationType::Profile(ID, CanonTemplate,
1954                                      CanonArgs.data(), NumArgs, *this);
1955
1956  void *InsertPos = 0;
1957  TemplateSpecializationType *Spec
1958    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
1959
1960  if (!Spec) {
1961    // Allocate a new canonical template specialization type.
1962    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
1963                          sizeof(TemplateArgument) * NumArgs),
1964                         TypeAlignment);
1965    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
1966                                                CanonArgs.data(), NumArgs,
1967                                                QualType());
1968    Types.push_back(Spec);
1969    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
1970  }
1971
1972  assert(Spec->isDependentType() &&
1973         "Non-dependent template-id type must have a canonical type");
1974  return QualType(Spec, 0);
1975}
1976
1977QualType
1978ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
1979                              NestedNameSpecifier *NNS,
1980                              QualType NamedType) {
1981  llvm::FoldingSetNodeID ID;
1982  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
1983
1984  void *InsertPos = 0;
1985  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
1986  if (T)
1987    return QualType(T, 0);
1988
1989  QualType Canon = NamedType;
1990  if (!Canon.isCanonical()) {
1991    Canon = getCanonicalType(NamedType);
1992    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
1993    assert(!CheckT && "Elaborated canonical type broken");
1994    (void)CheckT;
1995  }
1996
1997  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
1998  Types.push_back(T);
1999  ElaboratedTypes.InsertNode(T, InsertPos);
2000  return QualType(T, 0);
2001}
2002
2003QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2004                                          NestedNameSpecifier *NNS,
2005                                          const IdentifierInfo *Name,
2006                                          QualType Canon) {
2007  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2008
2009  if (Canon.isNull()) {
2010    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2011    ElaboratedTypeKeyword CanonKeyword = Keyword;
2012    if (Keyword == ETK_None)
2013      CanonKeyword = ETK_Typename;
2014
2015    if (CanonNNS != NNS || CanonKeyword != Keyword)
2016      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2017  }
2018
2019  llvm::FoldingSetNodeID ID;
2020  DependentNameType::Profile(ID, Keyword, NNS, Name);
2021
2022  void *InsertPos = 0;
2023  DependentNameType *T
2024    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2025  if (T)
2026    return QualType(T, 0);
2027
2028  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2029  Types.push_back(T);
2030  DependentNameTypes.InsertNode(T, InsertPos);
2031  return QualType(T, 0);
2032}
2033
2034QualType
2035ASTContext::getDependentTemplateSpecializationType(
2036                                 ElaboratedTypeKeyword Keyword,
2037                                 NestedNameSpecifier *NNS,
2038                                 const IdentifierInfo *Name,
2039                                 const TemplateArgumentListInfo &Args) {
2040  // TODO: avoid this copy
2041  llvm::SmallVector<TemplateArgument, 16> ArgCopy;
2042  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2043    ArgCopy.push_back(Args[I].getArgument());
2044  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2045                                                ArgCopy.size(),
2046                                                ArgCopy.data());
2047}
2048
2049QualType
2050ASTContext::getDependentTemplateSpecializationType(
2051                                 ElaboratedTypeKeyword Keyword,
2052                                 NestedNameSpecifier *NNS,
2053                                 const IdentifierInfo *Name,
2054                                 unsigned NumArgs,
2055                                 const TemplateArgument *Args) {
2056  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2057
2058  llvm::FoldingSetNodeID ID;
2059  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2060                                               Name, NumArgs, Args);
2061
2062  void *InsertPos = 0;
2063  DependentTemplateSpecializationType *T
2064    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2065  if (T)
2066    return QualType(T, 0);
2067
2068  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2069
2070  ElaboratedTypeKeyword CanonKeyword = Keyword;
2071  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2072
2073  bool AnyNonCanonArgs = false;
2074  llvm::SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2075  for (unsigned I = 0; I != NumArgs; ++I) {
2076    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2077    if (!CanonArgs[I].structurallyEquals(Args[I]))
2078      AnyNonCanonArgs = true;
2079  }
2080
2081  QualType Canon;
2082  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2083    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2084                                                   Name, NumArgs,
2085                                                   CanonArgs.data());
2086
2087    // Find the insert position again.
2088    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2089  }
2090
2091  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2092                        sizeof(TemplateArgument) * NumArgs),
2093                       TypeAlignment);
2094  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2095                                                    Name, NumArgs, Args, Canon);
2096  Types.push_back(T);
2097  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2098  return QualType(T, 0);
2099}
2100
2101/// CmpProtocolNames - Comparison predicate for sorting protocols
2102/// alphabetically.
2103static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2104                            const ObjCProtocolDecl *RHS) {
2105  return LHS->getDeclName() < RHS->getDeclName();
2106}
2107
2108static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2109                                unsigned NumProtocols) {
2110  if (NumProtocols == 0) return true;
2111
2112  for (unsigned i = 1; i != NumProtocols; ++i)
2113    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]))
2114      return false;
2115  return true;
2116}
2117
2118static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2119                                   unsigned &NumProtocols) {
2120  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2121
2122  // Sort protocols, keyed by name.
2123  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2124
2125  // Remove duplicates.
2126  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2127  NumProtocols = ProtocolsEnd-Protocols;
2128}
2129
2130QualType ASTContext::getObjCObjectType(QualType BaseType,
2131                                       ObjCProtocolDecl * const *Protocols,
2132                                       unsigned NumProtocols) {
2133  // If the base type is an interface and there aren't any protocols
2134  // to add, then the interface type will do just fine.
2135  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2136    return BaseType;
2137
2138  // Look in the folding set for an existing type.
2139  llvm::FoldingSetNodeID ID;
2140  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2141  void *InsertPos = 0;
2142  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2143    return QualType(QT, 0);
2144
2145  // Build the canonical type, which has the canonical base type and
2146  // a sorted-and-uniqued list of protocols.
2147  QualType Canonical;
2148  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2149  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2150    if (!ProtocolsSorted) {
2151      llvm::SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2152                                                     Protocols + NumProtocols);
2153      unsigned UniqueCount = NumProtocols;
2154
2155      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2156      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2157                                    &Sorted[0], UniqueCount);
2158    } else {
2159      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2160                                    Protocols, NumProtocols);
2161    }
2162
2163    // Regenerate InsertPos.
2164    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2165  }
2166
2167  unsigned Size = sizeof(ObjCObjectTypeImpl);
2168  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2169  void *Mem = Allocate(Size, TypeAlignment);
2170  ObjCObjectTypeImpl *T =
2171    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2172
2173  Types.push_back(T);
2174  ObjCObjectTypes.InsertNode(T, InsertPos);
2175  return QualType(T, 0);
2176}
2177
2178/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2179/// the given object type.
2180QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) {
2181  llvm::FoldingSetNodeID ID;
2182  ObjCObjectPointerType::Profile(ID, ObjectT);
2183
2184  void *InsertPos = 0;
2185  if (ObjCObjectPointerType *QT =
2186              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2187    return QualType(QT, 0);
2188
2189  // Find the canonical object type.
2190  QualType Canonical;
2191  if (!ObjectT.isCanonical()) {
2192    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2193
2194    // Regenerate InsertPos.
2195    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2196  }
2197
2198  // No match.
2199  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2200  ObjCObjectPointerType *QType =
2201    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2202
2203  Types.push_back(QType);
2204  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2205  return QualType(QType, 0);
2206}
2207
2208/// getObjCInterfaceType - Return the unique reference to the type for the
2209/// specified ObjC interface decl. The list of protocols is optional.
2210QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl) {
2211  if (Decl->TypeForDecl)
2212    return QualType(Decl->TypeForDecl, 0);
2213
2214  // FIXME: redeclarations?
2215  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2216  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2217  Decl->TypeForDecl = T;
2218  Types.push_back(T);
2219  return QualType(T, 0);
2220}
2221
2222/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2223/// TypeOfExprType AST's (since expression's are never shared). For example,
2224/// multiple declarations that refer to "typeof(x)" all contain different
2225/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2226/// on canonical type's (which are always unique).
2227QualType ASTContext::getTypeOfExprType(Expr *tofExpr) {
2228  TypeOfExprType *toe;
2229  if (tofExpr->isTypeDependent()) {
2230    llvm::FoldingSetNodeID ID;
2231    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2232
2233    void *InsertPos = 0;
2234    DependentTypeOfExprType *Canon
2235      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2236    if (Canon) {
2237      // We already have a "canonical" version of an identical, dependent
2238      // typeof(expr) type. Use that as our canonical type.
2239      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2240                                          QualType((TypeOfExprType*)Canon, 0));
2241    }
2242    else {
2243      // Build a new, canonical typeof(expr) type.
2244      Canon
2245        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2246      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2247      toe = Canon;
2248    }
2249  } else {
2250    QualType Canonical = getCanonicalType(tofExpr->getType());
2251    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2252  }
2253  Types.push_back(toe);
2254  return QualType(toe, 0);
2255}
2256
2257/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2258/// TypeOfType AST's. The only motivation to unique these nodes would be
2259/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2260/// an issue. This doesn't effect the type checker, since it operates
2261/// on canonical type's (which are always unique).
2262QualType ASTContext::getTypeOfType(QualType tofType) {
2263  QualType Canonical = getCanonicalType(tofType);
2264  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2265  Types.push_back(tot);
2266  return QualType(tot, 0);
2267}
2268
2269/// getDecltypeForExpr - Given an expr, will return the decltype for that
2270/// expression, according to the rules in C++0x [dcl.type.simple]p4
2271static QualType getDecltypeForExpr(const Expr *e, ASTContext &Context) {
2272  if (e->isTypeDependent())
2273    return Context.DependentTy;
2274
2275  // If e is an id expression or a class member access, decltype(e) is defined
2276  // as the type of the entity named by e.
2277  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2278    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2279      return VD->getType();
2280  }
2281  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2282    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2283      return FD->getType();
2284  }
2285  // If e is a function call or an invocation of an overloaded operator,
2286  // (parentheses around e are ignored), decltype(e) is defined as the
2287  // return type of that function.
2288  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2289    return CE->getCallReturnType();
2290
2291  QualType T = e->getType();
2292
2293  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2294  // defined as T&, otherwise decltype(e) is defined as T.
2295  if (e->isLvalue(Context) == Expr::LV_Valid)
2296    T = Context.getLValueReferenceType(T);
2297
2298  return T;
2299}
2300
2301/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2302/// DecltypeType AST's. The only motivation to unique these nodes would be
2303/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2304/// an issue. This doesn't effect the type checker, since it operates
2305/// on canonical type's (which are always unique).
2306QualType ASTContext::getDecltypeType(Expr *e) {
2307  DecltypeType *dt;
2308  if (e->isTypeDependent()) {
2309    llvm::FoldingSetNodeID ID;
2310    DependentDecltypeType::Profile(ID, *this, e);
2311
2312    void *InsertPos = 0;
2313    DependentDecltypeType *Canon
2314      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2315    if (Canon) {
2316      // We already have a "canonical" version of an equivalent, dependent
2317      // decltype type. Use that as our canonical type.
2318      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2319                                       QualType((DecltypeType*)Canon, 0));
2320    }
2321    else {
2322      // Build a new, canonical typeof(expr) type.
2323      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2324      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2325      dt = Canon;
2326    }
2327  } else {
2328    QualType T = getDecltypeForExpr(e, *this);
2329    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2330  }
2331  Types.push_back(dt);
2332  return QualType(dt, 0);
2333}
2334
2335/// getTagDeclType - Return the unique reference to the type for the
2336/// specified TagDecl (struct/union/class/enum) decl.
2337QualType ASTContext::getTagDeclType(const TagDecl *Decl) {
2338  assert (Decl);
2339  // FIXME: What is the design on getTagDeclType when it requires casting
2340  // away const?  mutable?
2341  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2342}
2343
2344/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2345/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2346/// needs to agree with the definition in <stddef.h>.
2347CanQualType ASTContext::getSizeType() const {
2348  return getFromTargetType(Target.getSizeType());
2349}
2350
2351/// getSignedWCharType - Return the type of "signed wchar_t".
2352/// Used when in C++, as a GCC extension.
2353QualType ASTContext::getSignedWCharType() const {
2354  // FIXME: derive from "Target" ?
2355  return WCharTy;
2356}
2357
2358/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
2359/// Used when in C++, as a GCC extension.
2360QualType ASTContext::getUnsignedWCharType() const {
2361  // FIXME: derive from "Target" ?
2362  return UnsignedIntTy;
2363}
2364
2365/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
2366/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
2367QualType ASTContext::getPointerDiffType() const {
2368  return getFromTargetType(Target.getPtrDiffType(0));
2369}
2370
2371//===----------------------------------------------------------------------===//
2372//                              Type Operators
2373//===----------------------------------------------------------------------===//
2374
2375CanQualType ASTContext::getCanonicalParamType(QualType T) {
2376  // Push qualifiers into arrays, and then discard any remaining
2377  // qualifiers.
2378  T = getCanonicalType(T);
2379  const Type *Ty = T.getTypePtr();
2380
2381  QualType Result;
2382  if (isa<ArrayType>(Ty)) {
2383    Result = getArrayDecayedType(QualType(Ty,0));
2384  } else if (isa<FunctionType>(Ty)) {
2385    Result = getPointerType(QualType(Ty, 0));
2386  } else {
2387    Result = QualType(Ty, 0);
2388  }
2389
2390  return CanQualType::CreateUnsafe(Result);
2391}
2392
2393/// getCanonicalType - Return the canonical (structural) type corresponding to
2394/// the specified potentially non-canonical type.  The non-canonical version
2395/// of a type may have many "decorated" versions of types.  Decorators can
2396/// include typedefs, 'typeof' operators, etc. The returned type is guaranteed
2397/// to be free of any of these, allowing two canonical types to be compared
2398/// for exact equality with a simple pointer comparison.
2399CanQualType ASTContext::getCanonicalType(QualType T) {
2400  QualifierCollector Quals;
2401  const Type *Ptr = Quals.strip(T);
2402  QualType CanType = Ptr->getCanonicalTypeInternal();
2403
2404  // The canonical internal type will be the canonical type *except*
2405  // that we push type qualifiers down through array types.
2406
2407  // If there are no new qualifiers to push down, stop here.
2408  if (!Quals.hasQualifiers())
2409    return CanQualType::CreateUnsafe(CanType);
2410
2411  // If the type qualifiers are on an array type, get the canonical
2412  // type of the array with the qualifiers applied to the element
2413  // type.
2414  ArrayType *AT = dyn_cast<ArrayType>(CanType);
2415  if (!AT)
2416    return CanQualType::CreateUnsafe(getQualifiedType(CanType, Quals));
2417
2418  // Get the canonical version of the element with the extra qualifiers on it.
2419  // This can recursively sink qualifiers through multiple levels of arrays.
2420  QualType NewEltTy = getQualifiedType(AT->getElementType(), Quals);
2421  NewEltTy = getCanonicalType(NewEltTy);
2422
2423  if (ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
2424    return CanQualType::CreateUnsafe(
2425             getConstantArrayType(NewEltTy, CAT->getSize(),
2426                                  CAT->getSizeModifier(),
2427                                  CAT->getIndexTypeCVRQualifiers()));
2428  if (IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT))
2429    return CanQualType::CreateUnsafe(
2430             getIncompleteArrayType(NewEltTy, IAT->getSizeModifier(),
2431                                    IAT->getIndexTypeCVRQualifiers()));
2432
2433  if (DependentSizedArrayType *DSAT = dyn_cast<DependentSizedArrayType>(AT))
2434    return CanQualType::CreateUnsafe(
2435             getDependentSizedArrayType(NewEltTy,
2436                                        DSAT->getSizeExpr() ?
2437                                          DSAT->getSizeExpr()->Retain() : 0,
2438                                        DSAT->getSizeModifier(),
2439                                        DSAT->getIndexTypeCVRQualifiers(),
2440                        DSAT->getBracketsRange())->getCanonicalTypeInternal());
2441
2442  VariableArrayType *VAT = cast<VariableArrayType>(AT);
2443  return CanQualType::CreateUnsafe(getVariableArrayType(NewEltTy,
2444                                                        VAT->getSizeExpr() ?
2445                                              VAT->getSizeExpr()->Retain() : 0,
2446                                                        VAT->getSizeModifier(),
2447                                              VAT->getIndexTypeCVRQualifiers(),
2448                                                     VAT->getBracketsRange()));
2449}
2450
2451QualType ASTContext::getUnqualifiedArrayType(QualType T,
2452                                             Qualifiers &Quals) {
2453  Quals = T.getQualifiers();
2454  const ArrayType *AT = getAsArrayType(T);
2455  if (!AT) {
2456    return T.getUnqualifiedType();
2457  }
2458
2459  QualType Elt = AT->getElementType();
2460  QualType UnqualElt = getUnqualifiedArrayType(Elt, Quals);
2461  if (Elt == UnqualElt)
2462    return T;
2463
2464  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
2465    return getConstantArrayType(UnqualElt, CAT->getSize(),
2466                                CAT->getSizeModifier(), 0);
2467  }
2468
2469  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
2470    return getIncompleteArrayType(UnqualElt, IAT->getSizeModifier(), 0);
2471  }
2472
2473  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
2474    return getVariableArrayType(UnqualElt,
2475                                VAT->getSizeExpr() ?
2476                                VAT->getSizeExpr()->Retain() : 0,
2477                                VAT->getSizeModifier(),
2478                                VAT->getIndexTypeCVRQualifiers(),
2479                                VAT->getBracketsRange());
2480  }
2481
2482  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
2483  return getDependentSizedArrayType(UnqualElt, DSAT->getSizeExpr()->Retain(),
2484                                    DSAT->getSizeModifier(), 0,
2485                                    SourceRange());
2486}
2487
2488/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
2489/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
2490/// they point to and return true. If T1 and T2 aren't pointer types
2491/// or pointer-to-member types, or if they are not similar at this
2492/// level, returns false and leaves T1 and T2 unchanged. Top-level
2493/// qualifiers on T1 and T2 are ignored. This function will typically
2494/// be called in a loop that successively "unwraps" pointer and
2495/// pointer-to-member types to compare them at each level.
2496bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
2497  const PointerType *T1PtrType = T1->getAs<PointerType>(),
2498                    *T2PtrType = T2->getAs<PointerType>();
2499  if (T1PtrType && T2PtrType) {
2500    T1 = T1PtrType->getPointeeType();
2501    T2 = T2PtrType->getPointeeType();
2502    return true;
2503  }
2504
2505  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
2506                          *T2MPType = T2->getAs<MemberPointerType>();
2507  if (T1MPType && T2MPType &&
2508      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
2509                             QualType(T2MPType->getClass(), 0))) {
2510    T1 = T1MPType->getPointeeType();
2511    T2 = T2MPType->getPointeeType();
2512    return true;
2513  }
2514
2515  if (getLangOptions().ObjC1) {
2516    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
2517                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
2518    if (T1OPType && T2OPType) {
2519      T1 = T1OPType->getPointeeType();
2520      T2 = T2OPType->getPointeeType();
2521      return true;
2522    }
2523  }
2524
2525  // FIXME: Block pointers, too?
2526
2527  return false;
2528}
2529
2530DeclarationName ASTContext::getNameForTemplate(TemplateName Name) {
2531  if (TemplateDecl *TD = Name.getAsTemplateDecl())
2532    return TD->getDeclName();
2533
2534  if (DependentTemplateName *DTN = Name.getAsDependentTemplateName()) {
2535    if (DTN->isIdentifier()) {
2536      return DeclarationNames.getIdentifier(DTN->getIdentifier());
2537    } else {
2538      return DeclarationNames.getCXXOperatorName(DTN->getOperator());
2539    }
2540  }
2541
2542  OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
2543  assert(Storage);
2544  return (*Storage->begin())->getDeclName();
2545}
2546
2547TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) {
2548  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
2549    if (TemplateTemplateParmDecl *TTP
2550                              = dyn_cast<TemplateTemplateParmDecl>(Template))
2551      Template = getCanonicalTemplateTemplateParmDecl(TTP);
2552
2553    // The canonical template name is the canonical template declaration.
2554    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
2555  }
2556
2557  assert(!Name.getAsOverloadedTemplate());
2558
2559  DependentTemplateName *DTN = Name.getAsDependentTemplateName();
2560  assert(DTN && "Non-dependent template names must refer to template decls.");
2561  return DTN->CanonicalTemplateName;
2562}
2563
2564bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
2565  X = getCanonicalTemplateName(X);
2566  Y = getCanonicalTemplateName(Y);
2567  return X.getAsVoidPointer() == Y.getAsVoidPointer();
2568}
2569
2570TemplateArgument
2571ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) {
2572  switch (Arg.getKind()) {
2573    case TemplateArgument::Null:
2574      return Arg;
2575
2576    case TemplateArgument::Expression:
2577      return Arg;
2578
2579    case TemplateArgument::Declaration:
2580      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
2581
2582    case TemplateArgument::Template:
2583      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
2584
2585    case TemplateArgument::Integral:
2586      return TemplateArgument(*Arg.getAsIntegral(),
2587                              getCanonicalType(Arg.getIntegralType()));
2588
2589    case TemplateArgument::Type:
2590      return TemplateArgument(getCanonicalType(Arg.getAsType()));
2591
2592    case TemplateArgument::Pack: {
2593      // FIXME: Allocate in ASTContext
2594      TemplateArgument *CanonArgs = new TemplateArgument[Arg.pack_size()];
2595      unsigned Idx = 0;
2596      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
2597                                        AEnd = Arg.pack_end();
2598           A != AEnd; (void)++A, ++Idx)
2599        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
2600
2601      TemplateArgument Result;
2602      Result.setArgumentPack(CanonArgs, Arg.pack_size(), false);
2603      return Result;
2604    }
2605  }
2606
2607  // Silence GCC warning
2608  assert(false && "Unhandled template argument kind");
2609  return TemplateArgument();
2610}
2611
2612NestedNameSpecifier *
2613ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) {
2614  if (!NNS)
2615    return 0;
2616
2617  switch (NNS->getKind()) {
2618  case NestedNameSpecifier::Identifier:
2619    // Canonicalize the prefix but keep the identifier the same.
2620    return NestedNameSpecifier::Create(*this,
2621                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
2622                                       NNS->getAsIdentifier());
2623
2624  case NestedNameSpecifier::Namespace:
2625    // A namespace is canonical; build a nested-name-specifier with
2626    // this namespace and no prefix.
2627    return NestedNameSpecifier::Create(*this, 0, NNS->getAsNamespace());
2628
2629  case NestedNameSpecifier::TypeSpec:
2630  case NestedNameSpecifier::TypeSpecWithTemplate: {
2631    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
2632    return NestedNameSpecifier::Create(*this, 0,
2633                 NNS->getKind() == NestedNameSpecifier::TypeSpecWithTemplate,
2634                                       T.getTypePtr());
2635  }
2636
2637  case NestedNameSpecifier::Global:
2638    // The global specifier is canonical and unique.
2639    return NNS;
2640  }
2641
2642  // Required to silence a GCC warning
2643  return 0;
2644}
2645
2646
2647const ArrayType *ASTContext::getAsArrayType(QualType T) {
2648  // Handle the non-qualified case efficiently.
2649  if (!T.hasLocalQualifiers()) {
2650    // Handle the common positive case fast.
2651    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
2652      return AT;
2653  }
2654
2655  // Handle the common negative case fast.
2656  QualType CType = T->getCanonicalTypeInternal();
2657  if (!isa<ArrayType>(CType))
2658    return 0;
2659
2660  // Apply any qualifiers from the array type to the element type.  This
2661  // implements C99 6.7.3p8: "If the specification of an array type includes
2662  // any type qualifiers, the element type is so qualified, not the array type."
2663
2664  // If we get here, we either have type qualifiers on the type, or we have
2665  // sugar such as a typedef in the way.  If we have type qualifiers on the type
2666  // we must propagate them down into the element type.
2667
2668  QualifierCollector Qs;
2669  const Type *Ty = Qs.strip(T.getDesugaredType());
2670
2671  // If we have a simple case, just return now.
2672  const ArrayType *ATy = dyn_cast<ArrayType>(Ty);
2673  if (ATy == 0 || Qs.empty())
2674    return ATy;
2675
2676  // Otherwise, we have an array and we have qualifiers on it.  Push the
2677  // qualifiers into the array element type and return a new array type.
2678  // Get the canonical version of the element with the extra qualifiers on it.
2679  // This can recursively sink qualifiers through multiple levels of arrays.
2680  QualType NewEltTy = getQualifiedType(ATy->getElementType(), Qs);
2681
2682  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
2683    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
2684                                                CAT->getSizeModifier(),
2685                                           CAT->getIndexTypeCVRQualifiers()));
2686  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
2687    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
2688                                                  IAT->getSizeModifier(),
2689                                           IAT->getIndexTypeCVRQualifiers()));
2690
2691  if (const DependentSizedArrayType *DSAT
2692        = dyn_cast<DependentSizedArrayType>(ATy))
2693    return cast<ArrayType>(
2694                     getDependentSizedArrayType(NewEltTy,
2695                                                DSAT->getSizeExpr() ?
2696                                              DSAT->getSizeExpr()->Retain() : 0,
2697                                                DSAT->getSizeModifier(),
2698                                              DSAT->getIndexTypeCVRQualifiers(),
2699                                                DSAT->getBracketsRange()));
2700
2701  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
2702  return cast<ArrayType>(getVariableArrayType(NewEltTy,
2703                                              VAT->getSizeExpr() ?
2704                                              VAT->getSizeExpr()->Retain() : 0,
2705                                              VAT->getSizeModifier(),
2706                                              VAT->getIndexTypeCVRQualifiers(),
2707                                              VAT->getBracketsRange()));
2708}
2709
2710
2711/// getArrayDecayedType - Return the properly qualified result of decaying the
2712/// specified array type to a pointer.  This operation is non-trivial when
2713/// handling typedefs etc.  The canonical type of "T" must be an array type,
2714/// this returns a pointer to a properly qualified element of the array.
2715///
2716/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
2717QualType ASTContext::getArrayDecayedType(QualType Ty) {
2718  // Get the element type with 'getAsArrayType' so that we don't lose any
2719  // typedefs in the element type of the array.  This also handles propagation
2720  // of type qualifiers from the array type into the element type if present
2721  // (C99 6.7.3p8).
2722  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
2723  assert(PrettyArrayType && "Not an array type!");
2724
2725  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
2726
2727  // int x[restrict 4] ->  int *restrict
2728  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
2729}
2730
2731QualType ASTContext::getBaseElementType(QualType QT) {
2732  QualifierCollector Qs;
2733  while (const ArrayType *AT = getAsArrayType(QualType(Qs.strip(QT), 0)))
2734    QT = AT->getElementType();
2735  return Qs.apply(QT);
2736}
2737
2738QualType ASTContext::getBaseElementType(const ArrayType *AT) {
2739  QualType ElemTy = AT->getElementType();
2740
2741  if (const ArrayType *AT = getAsArrayType(ElemTy))
2742    return getBaseElementType(AT);
2743
2744  return ElemTy;
2745}
2746
2747/// getConstantArrayElementCount - Returns number of constant array elements.
2748uint64_t
2749ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
2750  uint64_t ElementCount = 1;
2751  do {
2752    ElementCount *= CA->getSize().getZExtValue();
2753    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
2754  } while (CA);
2755  return ElementCount;
2756}
2757
2758/// getFloatingRank - Return a relative rank for floating point types.
2759/// This routine will assert if passed a built-in type that isn't a float.
2760static FloatingRank getFloatingRank(QualType T) {
2761  if (const ComplexType *CT = T->getAs<ComplexType>())
2762    return getFloatingRank(CT->getElementType());
2763
2764  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
2765  switch (T->getAs<BuiltinType>()->getKind()) {
2766  default: assert(0 && "getFloatingRank(): not a floating type");
2767  case BuiltinType::Float:      return FloatRank;
2768  case BuiltinType::Double:     return DoubleRank;
2769  case BuiltinType::LongDouble: return LongDoubleRank;
2770  }
2771}
2772
2773/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
2774/// point or a complex type (based on typeDomain/typeSize).
2775/// 'typeDomain' is a real floating point or complex type.
2776/// 'typeSize' is a real floating point or complex type.
2777QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
2778                                                       QualType Domain) const {
2779  FloatingRank EltRank = getFloatingRank(Size);
2780  if (Domain->isComplexType()) {
2781    switch (EltRank) {
2782    default: assert(0 && "getFloatingRank(): illegal value for rank");
2783    case FloatRank:      return FloatComplexTy;
2784    case DoubleRank:     return DoubleComplexTy;
2785    case LongDoubleRank: return LongDoubleComplexTy;
2786    }
2787  }
2788
2789  assert(Domain->isRealFloatingType() && "Unknown domain!");
2790  switch (EltRank) {
2791  default: assert(0 && "getFloatingRank(): illegal value for rank");
2792  case FloatRank:      return FloatTy;
2793  case DoubleRank:     return DoubleTy;
2794  case LongDoubleRank: return LongDoubleTy;
2795  }
2796}
2797
2798/// getFloatingTypeOrder - Compare the rank of the two specified floating
2799/// point types, ignoring the domain of the type (i.e. 'double' ==
2800/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2801/// LHS < RHS, return -1.
2802int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) {
2803  FloatingRank LHSR = getFloatingRank(LHS);
2804  FloatingRank RHSR = getFloatingRank(RHS);
2805
2806  if (LHSR == RHSR)
2807    return 0;
2808  if (LHSR > RHSR)
2809    return 1;
2810  return -1;
2811}
2812
2813/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
2814/// routine will assert if passed a built-in type that isn't an integer or enum,
2815/// or if it is not canonicalized.
2816unsigned ASTContext::getIntegerRank(Type *T) {
2817  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
2818  if (EnumType* ET = dyn_cast<EnumType>(T))
2819    T = ET->getDecl()->getPromotionType().getTypePtr();
2820
2821  if (T->isSpecificBuiltinType(BuiltinType::WChar))
2822    T = getFromTargetType(Target.getWCharType()).getTypePtr();
2823
2824  if (T->isSpecificBuiltinType(BuiltinType::Char16))
2825    T = getFromTargetType(Target.getChar16Type()).getTypePtr();
2826
2827  if (T->isSpecificBuiltinType(BuiltinType::Char32))
2828    T = getFromTargetType(Target.getChar32Type()).getTypePtr();
2829
2830  switch (cast<BuiltinType>(T)->getKind()) {
2831  default: assert(0 && "getIntegerRank(): not a built-in integer");
2832  case BuiltinType::Bool:
2833    return 1 + (getIntWidth(BoolTy) << 3);
2834  case BuiltinType::Char_S:
2835  case BuiltinType::Char_U:
2836  case BuiltinType::SChar:
2837  case BuiltinType::UChar:
2838    return 2 + (getIntWidth(CharTy) << 3);
2839  case BuiltinType::Short:
2840  case BuiltinType::UShort:
2841    return 3 + (getIntWidth(ShortTy) << 3);
2842  case BuiltinType::Int:
2843  case BuiltinType::UInt:
2844    return 4 + (getIntWidth(IntTy) << 3);
2845  case BuiltinType::Long:
2846  case BuiltinType::ULong:
2847    return 5 + (getIntWidth(LongTy) << 3);
2848  case BuiltinType::LongLong:
2849  case BuiltinType::ULongLong:
2850    return 6 + (getIntWidth(LongLongTy) << 3);
2851  case BuiltinType::Int128:
2852  case BuiltinType::UInt128:
2853    return 7 + (getIntWidth(Int128Ty) << 3);
2854  }
2855}
2856
2857/// \brief Whether this is a promotable bitfield reference according
2858/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
2859///
2860/// \returns the type this bit-field will promote to, or NULL if no
2861/// promotion occurs.
2862QualType ASTContext::isPromotableBitField(Expr *E) {
2863  if (E->isTypeDependent() || E->isValueDependent())
2864    return QualType();
2865
2866  FieldDecl *Field = E->getBitField();
2867  if (!Field)
2868    return QualType();
2869
2870  QualType FT = Field->getType();
2871
2872  llvm::APSInt BitWidthAP = Field->getBitWidth()->EvaluateAsInt(*this);
2873  uint64_t BitWidth = BitWidthAP.getZExtValue();
2874  uint64_t IntSize = getTypeSize(IntTy);
2875  // GCC extension compatibility: if the bit-field size is less than or equal
2876  // to the size of int, it gets promoted no matter what its type is.
2877  // For instance, unsigned long bf : 4 gets promoted to signed int.
2878  if (BitWidth < IntSize)
2879    return IntTy;
2880
2881  if (BitWidth == IntSize)
2882    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
2883
2884  // Types bigger than int are not subject to promotions, and therefore act
2885  // like the base type.
2886  // FIXME: This doesn't quite match what gcc does, but what gcc does here
2887  // is ridiculous.
2888  return QualType();
2889}
2890
2891/// getPromotedIntegerType - Returns the type that Promotable will
2892/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
2893/// integer type.
2894QualType ASTContext::getPromotedIntegerType(QualType Promotable) {
2895  assert(!Promotable.isNull());
2896  assert(Promotable->isPromotableIntegerType());
2897  if (const EnumType *ET = Promotable->getAs<EnumType>())
2898    return ET->getDecl()->getPromotionType();
2899  if (Promotable->isSignedIntegerType())
2900    return IntTy;
2901  uint64_t PromotableSize = getTypeSize(Promotable);
2902  uint64_t IntSize = getTypeSize(IntTy);
2903  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
2904  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
2905}
2906
2907/// getIntegerTypeOrder - Returns the highest ranked integer type:
2908/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2909/// LHS < RHS, return -1.
2910int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) {
2911  Type *LHSC = getCanonicalType(LHS).getTypePtr();
2912  Type *RHSC = getCanonicalType(RHS).getTypePtr();
2913  if (LHSC == RHSC) return 0;
2914
2915  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
2916  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
2917
2918  unsigned LHSRank = getIntegerRank(LHSC);
2919  unsigned RHSRank = getIntegerRank(RHSC);
2920
2921  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
2922    if (LHSRank == RHSRank) return 0;
2923    return LHSRank > RHSRank ? 1 : -1;
2924  }
2925
2926  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
2927  if (LHSUnsigned) {
2928    // If the unsigned [LHS] type is larger, return it.
2929    if (LHSRank >= RHSRank)
2930      return 1;
2931
2932    // If the signed type can represent all values of the unsigned type, it
2933    // wins.  Because we are dealing with 2's complement and types that are
2934    // powers of two larger than each other, this is always safe.
2935    return -1;
2936  }
2937
2938  // If the unsigned [RHS] type is larger, return it.
2939  if (RHSRank >= LHSRank)
2940    return -1;
2941
2942  // If the signed type can represent all values of the unsigned type, it
2943  // wins.  Because we are dealing with 2's complement and types that are
2944  // powers of two larger than each other, this is always safe.
2945  return 1;
2946}
2947
2948static RecordDecl *
2949CreateRecordDecl(ASTContext &Ctx, RecordDecl::TagKind TK, DeclContext *DC,
2950                 SourceLocation L, IdentifierInfo *Id) {
2951  if (Ctx.getLangOptions().CPlusPlus)
2952    return CXXRecordDecl::Create(Ctx, TK, DC, L, Id);
2953  else
2954    return RecordDecl::Create(Ctx, TK, DC, L, Id);
2955}
2956
2957// getCFConstantStringType - Return the type used for constant CFStrings.
2958QualType ASTContext::getCFConstantStringType() {
2959  if (!CFConstantStringTypeDecl) {
2960    CFConstantStringTypeDecl =
2961      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
2962                       &Idents.get("NSConstantString"));
2963    CFConstantStringTypeDecl->startDefinition();
2964
2965    QualType FieldTypes[4];
2966
2967    // const int *isa;
2968    FieldTypes[0] = getPointerType(IntTy.withConst());
2969    // int flags;
2970    FieldTypes[1] = IntTy;
2971    // const char *str;
2972    FieldTypes[2] = getPointerType(CharTy.withConst());
2973    // long length;
2974    FieldTypes[3] = LongTy;
2975
2976    // Create fields
2977    for (unsigned i = 0; i < 4; ++i) {
2978      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
2979                                           SourceLocation(), 0,
2980                                           FieldTypes[i], /*TInfo=*/0,
2981                                           /*BitWidth=*/0,
2982                                           /*Mutable=*/false);
2983      Field->setAccess(AS_public);
2984      CFConstantStringTypeDecl->addDecl(Field);
2985    }
2986
2987    CFConstantStringTypeDecl->completeDefinition();
2988  }
2989
2990  return getTagDeclType(CFConstantStringTypeDecl);
2991}
2992
2993void ASTContext::setCFConstantStringType(QualType T) {
2994  const RecordType *Rec = T->getAs<RecordType>();
2995  assert(Rec && "Invalid CFConstantStringType");
2996  CFConstantStringTypeDecl = Rec->getDecl();
2997}
2998
2999// getNSConstantStringType - Return the type used for constant NSStrings.
3000QualType ASTContext::getNSConstantStringType() {
3001  if (!NSConstantStringTypeDecl) {
3002    NSConstantStringTypeDecl =
3003    CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3004                     &Idents.get("__builtin_NSString"));
3005    NSConstantStringTypeDecl->startDefinition();
3006
3007    QualType FieldTypes[3];
3008
3009    // const int *isa;
3010    FieldTypes[0] = getPointerType(IntTy.withConst());
3011    // const char *str;
3012    FieldTypes[1] = getPointerType(CharTy.withConst());
3013    // unsigned int length;
3014    FieldTypes[2] = UnsignedIntTy;
3015
3016    // Create fields
3017    for (unsigned i = 0; i < 3; ++i) {
3018      FieldDecl *Field = FieldDecl::Create(*this, NSConstantStringTypeDecl,
3019                                           SourceLocation(), 0,
3020                                           FieldTypes[i], /*TInfo=*/0,
3021                                           /*BitWidth=*/0,
3022                                           /*Mutable=*/false);
3023      Field->setAccess(AS_public);
3024      NSConstantStringTypeDecl->addDecl(Field);
3025    }
3026
3027    NSConstantStringTypeDecl->completeDefinition();
3028  }
3029
3030  return getTagDeclType(NSConstantStringTypeDecl);
3031}
3032
3033void ASTContext::setNSConstantStringType(QualType T) {
3034  const RecordType *Rec = T->getAs<RecordType>();
3035  assert(Rec && "Invalid NSConstantStringType");
3036  NSConstantStringTypeDecl = Rec->getDecl();
3037}
3038
3039QualType ASTContext::getObjCFastEnumerationStateType() {
3040  if (!ObjCFastEnumerationStateTypeDecl) {
3041    ObjCFastEnumerationStateTypeDecl =
3042      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3043                       &Idents.get("__objcFastEnumerationState"));
3044    ObjCFastEnumerationStateTypeDecl->startDefinition();
3045
3046    QualType FieldTypes[] = {
3047      UnsignedLongTy,
3048      getPointerType(ObjCIdTypedefType),
3049      getPointerType(UnsignedLongTy),
3050      getConstantArrayType(UnsignedLongTy,
3051                           llvm::APInt(32, 5), ArrayType::Normal, 0)
3052    };
3053
3054    for (size_t i = 0; i < 4; ++i) {
3055      FieldDecl *Field = FieldDecl::Create(*this,
3056                                           ObjCFastEnumerationStateTypeDecl,
3057                                           SourceLocation(), 0,
3058                                           FieldTypes[i], /*TInfo=*/0,
3059                                           /*BitWidth=*/0,
3060                                           /*Mutable=*/false);
3061      Field->setAccess(AS_public);
3062      ObjCFastEnumerationStateTypeDecl->addDecl(Field);
3063    }
3064    if (getLangOptions().CPlusPlus)
3065      if (CXXRecordDecl *CXXRD =
3066            dyn_cast<CXXRecordDecl>(ObjCFastEnumerationStateTypeDecl))
3067        CXXRD->setEmpty(false);
3068
3069    ObjCFastEnumerationStateTypeDecl->completeDefinition();
3070  }
3071
3072  return getTagDeclType(ObjCFastEnumerationStateTypeDecl);
3073}
3074
3075QualType ASTContext::getBlockDescriptorType() {
3076  if (BlockDescriptorType)
3077    return getTagDeclType(BlockDescriptorType);
3078
3079  RecordDecl *T;
3080  // FIXME: Needs the FlagAppleBlock bit.
3081  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3082                       &Idents.get("__block_descriptor"));
3083  T->startDefinition();
3084
3085  QualType FieldTypes[] = {
3086    UnsignedLongTy,
3087    UnsignedLongTy,
3088  };
3089
3090  const char *FieldNames[] = {
3091    "reserved",
3092    "Size"
3093  };
3094
3095  for (size_t i = 0; i < 2; ++i) {
3096    FieldDecl *Field = FieldDecl::Create(*this,
3097                                         T,
3098                                         SourceLocation(),
3099                                         &Idents.get(FieldNames[i]),
3100                                         FieldTypes[i], /*TInfo=*/0,
3101                                         /*BitWidth=*/0,
3102                                         /*Mutable=*/false);
3103    Field->setAccess(AS_public);
3104    T->addDecl(Field);
3105  }
3106
3107  T->completeDefinition();
3108
3109  BlockDescriptorType = T;
3110
3111  return getTagDeclType(BlockDescriptorType);
3112}
3113
3114void ASTContext::setBlockDescriptorType(QualType T) {
3115  const RecordType *Rec = T->getAs<RecordType>();
3116  assert(Rec && "Invalid BlockDescriptorType");
3117  BlockDescriptorType = Rec->getDecl();
3118}
3119
3120QualType ASTContext::getBlockDescriptorExtendedType() {
3121  if (BlockDescriptorExtendedType)
3122    return getTagDeclType(BlockDescriptorExtendedType);
3123
3124  RecordDecl *T;
3125  // FIXME: Needs the FlagAppleBlock bit.
3126  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3127                       &Idents.get("__block_descriptor_withcopydispose"));
3128  T->startDefinition();
3129
3130  QualType FieldTypes[] = {
3131    UnsignedLongTy,
3132    UnsignedLongTy,
3133    getPointerType(VoidPtrTy),
3134    getPointerType(VoidPtrTy)
3135  };
3136
3137  const char *FieldNames[] = {
3138    "reserved",
3139    "Size",
3140    "CopyFuncPtr",
3141    "DestroyFuncPtr"
3142  };
3143
3144  for (size_t i = 0; i < 4; ++i) {
3145    FieldDecl *Field = FieldDecl::Create(*this,
3146                                         T,
3147                                         SourceLocation(),
3148                                         &Idents.get(FieldNames[i]),
3149                                         FieldTypes[i], /*TInfo=*/0,
3150                                         /*BitWidth=*/0,
3151                                         /*Mutable=*/false);
3152    Field->setAccess(AS_public);
3153    T->addDecl(Field);
3154  }
3155
3156  T->completeDefinition();
3157
3158  BlockDescriptorExtendedType = T;
3159
3160  return getTagDeclType(BlockDescriptorExtendedType);
3161}
3162
3163void ASTContext::setBlockDescriptorExtendedType(QualType T) {
3164  const RecordType *Rec = T->getAs<RecordType>();
3165  assert(Rec && "Invalid BlockDescriptorType");
3166  BlockDescriptorExtendedType = Rec->getDecl();
3167}
3168
3169bool ASTContext::BlockRequiresCopying(QualType Ty) {
3170  if (Ty->isBlockPointerType())
3171    return true;
3172  if (isObjCNSObjectType(Ty))
3173    return true;
3174  if (Ty->isObjCObjectPointerType())
3175    return true;
3176  return false;
3177}
3178
3179QualType ASTContext::BuildByRefType(const char *DeclName, QualType Ty) {
3180  //  type = struct __Block_byref_1_X {
3181  //    void *__isa;
3182  //    struct __Block_byref_1_X *__forwarding;
3183  //    unsigned int __flags;
3184  //    unsigned int __size;
3185  //    void *__copy_helper;		// as needed
3186  //    void *__destroy_help		// as needed
3187  //    int X;
3188  //  } *
3189
3190  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3191
3192  // FIXME: Move up
3193  llvm::SmallString<36> Name;
3194  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3195                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3196  RecordDecl *T;
3197  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3198                       &Idents.get(Name.str()));
3199  T->startDefinition();
3200  QualType Int32Ty = IntTy;
3201  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3202  QualType FieldTypes[] = {
3203    getPointerType(VoidPtrTy),
3204    getPointerType(getTagDeclType(T)),
3205    Int32Ty,
3206    Int32Ty,
3207    getPointerType(VoidPtrTy),
3208    getPointerType(VoidPtrTy),
3209    Ty
3210  };
3211
3212  const char *FieldNames[] = {
3213    "__isa",
3214    "__forwarding",
3215    "__flags",
3216    "__size",
3217    "__copy_helper",
3218    "__destroy_helper",
3219    DeclName,
3220  };
3221
3222  for (size_t i = 0; i < 7; ++i) {
3223    if (!HasCopyAndDispose && i >=4 && i <= 5)
3224      continue;
3225    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3226                                         &Idents.get(FieldNames[i]),
3227                                         FieldTypes[i], /*TInfo=*/0,
3228                                         /*BitWidth=*/0, /*Mutable=*/false);
3229    Field->setAccess(AS_public);
3230    T->addDecl(Field);
3231  }
3232
3233  T->completeDefinition();
3234
3235  return getPointerType(getTagDeclType(T));
3236}
3237
3238
3239QualType ASTContext::getBlockParmType(
3240  bool BlockHasCopyDispose,
3241  llvm::SmallVectorImpl<const Expr *> &Layout) {
3242
3243  // FIXME: Move up
3244  llvm::SmallString<36> Name;
3245  llvm::raw_svector_ostream(Name) << "__block_literal_"
3246                                  << ++UniqueBlockParmTypeID;
3247  RecordDecl *T;
3248  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3249                       &Idents.get(Name.str()));
3250  T->startDefinition();
3251  QualType FieldTypes[] = {
3252    getPointerType(VoidPtrTy),
3253    IntTy,
3254    IntTy,
3255    getPointerType(VoidPtrTy),
3256    (BlockHasCopyDispose ?
3257     getPointerType(getBlockDescriptorExtendedType()) :
3258     getPointerType(getBlockDescriptorType()))
3259  };
3260
3261  const char *FieldNames[] = {
3262    "__isa",
3263    "__flags",
3264    "__reserved",
3265    "__FuncPtr",
3266    "__descriptor"
3267  };
3268
3269  for (size_t i = 0; i < 5; ++i) {
3270    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3271                                         &Idents.get(FieldNames[i]),
3272                                         FieldTypes[i], /*TInfo=*/0,
3273                                         /*BitWidth=*/0, /*Mutable=*/false);
3274    Field->setAccess(AS_public);
3275    T->addDecl(Field);
3276  }
3277
3278  for (unsigned i = 0; i < Layout.size(); ++i) {
3279    const Expr *E = Layout[i];
3280
3281    QualType FieldType = E->getType();
3282    IdentifierInfo *FieldName = 0;
3283    if (isa<CXXThisExpr>(E)) {
3284      FieldName = &Idents.get("this");
3285    } else if (const BlockDeclRefExpr *BDRE = dyn_cast<BlockDeclRefExpr>(E)) {
3286      const ValueDecl *D = BDRE->getDecl();
3287      FieldName = D->getIdentifier();
3288      if (BDRE->isByRef())
3289        FieldType = BuildByRefType(D->getNameAsCString(), FieldType);
3290    } else {
3291      // Padding.
3292      assert(isa<ConstantArrayType>(FieldType) &&
3293             isa<DeclRefExpr>(E) &&
3294             !cast<DeclRefExpr>(E)->getDecl()->getDeclName() &&
3295             "doesn't match characteristics of padding decl");
3296    }
3297
3298    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3299                                         FieldName, FieldType, /*TInfo=*/0,
3300                                         /*BitWidth=*/0, /*Mutable=*/false);
3301    Field->setAccess(AS_public);
3302    T->addDecl(Field);
3303  }
3304
3305  T->completeDefinition();
3306
3307  return getPointerType(getTagDeclType(T));
3308}
3309
3310void ASTContext::setObjCFastEnumerationStateType(QualType T) {
3311  const RecordType *Rec = T->getAs<RecordType>();
3312  assert(Rec && "Invalid ObjCFAstEnumerationStateType");
3313  ObjCFastEnumerationStateTypeDecl = Rec->getDecl();
3314}
3315
3316// This returns true if a type has been typedefed to BOOL:
3317// typedef <type> BOOL;
3318static bool isTypeTypedefedAsBOOL(QualType T) {
3319  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3320    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3321      return II->isStr("BOOL");
3322
3323  return false;
3324}
3325
3326/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3327/// purpose.
3328CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) {
3329  CharUnits sz = getTypeSizeInChars(type);
3330
3331  // Make all integer and enum types at least as large as an int
3332  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3333    sz = std::max(sz, getTypeSizeInChars(IntTy));
3334  // Treat arrays as pointers, since that's how they're passed in.
3335  else if (type->isArrayType())
3336    sz = getTypeSizeInChars(VoidPtrTy);
3337  return sz;
3338}
3339
3340static inline
3341std::string charUnitsToString(const CharUnits &CU) {
3342  return llvm::itostr(CU.getQuantity());
3343}
3344
3345/// getObjCEncodingForBlockDecl - Return the encoded type for this block
3346/// declaration.
3347void ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr,
3348                                             std::string& S) {
3349  const BlockDecl *Decl = Expr->getBlockDecl();
3350  QualType BlockTy =
3351      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3352  // Encode result type.
3353  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3354  // Compute size of all parameters.
3355  // Start with computing size of a pointer in number of bytes.
3356  // FIXME: There might(should) be a better way of doing this computation!
3357  SourceLocation Loc;
3358  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3359  CharUnits ParmOffset = PtrSize;
3360  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3361       E = Decl->param_end(); PI != E; ++PI) {
3362    QualType PType = (*PI)->getType();
3363    CharUnits sz = getObjCEncodingTypeSize(PType);
3364    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3365    ParmOffset += sz;
3366  }
3367  // Size of the argument frame
3368  S += charUnitsToString(ParmOffset);
3369  // Block pointer and offset.
3370  S += "@?0";
3371  ParmOffset = PtrSize;
3372
3373  // Argument types.
3374  ParmOffset = PtrSize;
3375  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3376       Decl->param_end(); PI != E; ++PI) {
3377    ParmVarDecl *PVDecl = *PI;
3378    QualType PType = PVDecl->getOriginalType();
3379    if (const ArrayType *AT =
3380          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3381      // Use array's original type only if it has known number of
3382      // elements.
3383      if (!isa<ConstantArrayType>(AT))
3384        PType = PVDecl->getType();
3385    } else if (PType->isFunctionType())
3386      PType = PVDecl->getType();
3387    getObjCEncodingForType(PType, S);
3388    S += charUnitsToString(ParmOffset);
3389    ParmOffset += getObjCEncodingTypeSize(PType);
3390  }
3391}
3392
3393/// getObjCEncodingForMethodDecl - Return the encoded type for this method
3394/// declaration.
3395void ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
3396                                              std::string& S) {
3397  // FIXME: This is not very efficient.
3398  // Encode type qualifer, 'in', 'inout', etc. for the return type.
3399  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
3400  // Encode result type.
3401  getObjCEncodingForType(Decl->getResultType(), S);
3402  // Compute size of all parameters.
3403  // Start with computing size of a pointer in number of bytes.
3404  // FIXME: There might(should) be a better way of doing this computation!
3405  SourceLocation Loc;
3406  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3407  // The first two arguments (self and _cmd) are pointers; account for
3408  // their size.
3409  CharUnits ParmOffset = 2 * PtrSize;
3410  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3411       E = Decl->sel_param_end(); PI != E; ++PI) {
3412    QualType PType = (*PI)->getType();
3413    CharUnits sz = getObjCEncodingTypeSize(PType);
3414    assert (sz.isPositive() &&
3415        "getObjCEncodingForMethodDecl - Incomplete param type");
3416    ParmOffset += sz;
3417  }
3418  S += charUnitsToString(ParmOffset);
3419  S += "@0:";
3420  S += charUnitsToString(PtrSize);
3421
3422  // Argument types.
3423  ParmOffset = 2 * PtrSize;
3424  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3425       E = Decl->sel_param_end(); PI != E; ++PI) {
3426    ParmVarDecl *PVDecl = *PI;
3427    QualType PType = PVDecl->getOriginalType();
3428    if (const ArrayType *AT =
3429          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3430      // Use array's original type only if it has known number of
3431      // elements.
3432      if (!isa<ConstantArrayType>(AT))
3433        PType = PVDecl->getType();
3434    } else if (PType->isFunctionType())
3435      PType = PVDecl->getType();
3436    // Process argument qualifiers for user supplied arguments; such as,
3437    // 'in', 'inout', etc.
3438    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
3439    getObjCEncodingForType(PType, S);
3440    S += charUnitsToString(ParmOffset);
3441    ParmOffset += getObjCEncodingTypeSize(PType);
3442  }
3443}
3444
3445/// getObjCEncodingForPropertyDecl - Return the encoded type for this
3446/// property declaration. If non-NULL, Container must be either an
3447/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
3448/// NULL when getting encodings for protocol properties.
3449/// Property attributes are stored as a comma-delimited C string. The simple
3450/// attributes readonly and bycopy are encoded as single characters. The
3451/// parametrized attributes, getter=name, setter=name, and ivar=name, are
3452/// encoded as single characters, followed by an identifier. Property types
3453/// are also encoded as a parametrized attribute. The characters used to encode
3454/// these attributes are defined by the following enumeration:
3455/// @code
3456/// enum PropertyAttributes {
3457/// kPropertyReadOnly = 'R',   // property is read-only.
3458/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
3459/// kPropertyByref = '&',  // property is a reference to the value last assigned
3460/// kPropertyDynamic = 'D',    // property is dynamic
3461/// kPropertyGetter = 'G',     // followed by getter selector name
3462/// kPropertySetter = 'S',     // followed by setter selector name
3463/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
3464/// kPropertyType = 't'              // followed by old-style type encoding.
3465/// kPropertyWeak = 'W'              // 'weak' property
3466/// kPropertyStrong = 'P'            // property GC'able
3467/// kPropertyNonAtomic = 'N'         // property non-atomic
3468/// };
3469/// @endcode
3470void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
3471                                                const Decl *Container,
3472                                                std::string& S) {
3473  // Collect information from the property implementation decl(s).
3474  bool Dynamic = false;
3475  ObjCPropertyImplDecl *SynthesizePID = 0;
3476
3477  // FIXME: Duplicated code due to poor abstraction.
3478  if (Container) {
3479    if (const ObjCCategoryImplDecl *CID =
3480        dyn_cast<ObjCCategoryImplDecl>(Container)) {
3481      for (ObjCCategoryImplDecl::propimpl_iterator
3482             i = CID->propimpl_begin(), e = CID->propimpl_end();
3483           i != e; ++i) {
3484        ObjCPropertyImplDecl *PID = *i;
3485        if (PID->getPropertyDecl() == PD) {
3486          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3487            Dynamic = true;
3488          } else {
3489            SynthesizePID = PID;
3490          }
3491        }
3492      }
3493    } else {
3494      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
3495      for (ObjCCategoryImplDecl::propimpl_iterator
3496             i = OID->propimpl_begin(), e = OID->propimpl_end();
3497           i != e; ++i) {
3498        ObjCPropertyImplDecl *PID = *i;
3499        if (PID->getPropertyDecl() == PD) {
3500          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3501            Dynamic = true;
3502          } else {
3503            SynthesizePID = PID;
3504          }
3505        }
3506      }
3507    }
3508  }
3509
3510  // FIXME: This is not very efficient.
3511  S = "T";
3512
3513  // Encode result type.
3514  // GCC has some special rules regarding encoding of properties which
3515  // closely resembles encoding of ivars.
3516  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
3517                             true /* outermost type */,
3518                             true /* encoding for property */);
3519
3520  if (PD->isReadOnly()) {
3521    S += ",R";
3522  } else {
3523    switch (PD->getSetterKind()) {
3524    case ObjCPropertyDecl::Assign: break;
3525    case ObjCPropertyDecl::Copy:   S += ",C"; break;
3526    case ObjCPropertyDecl::Retain: S += ",&"; break;
3527    }
3528  }
3529
3530  // It really isn't clear at all what this means, since properties
3531  // are "dynamic by default".
3532  if (Dynamic)
3533    S += ",D";
3534
3535  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
3536    S += ",N";
3537
3538  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
3539    S += ",G";
3540    S += PD->getGetterName().getAsString();
3541  }
3542
3543  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
3544    S += ",S";
3545    S += PD->getSetterName().getAsString();
3546  }
3547
3548  if (SynthesizePID) {
3549    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
3550    S += ",V";
3551    S += OID->getNameAsString();
3552  }
3553
3554  // FIXME: OBJCGC: weak & strong
3555}
3556
3557/// getLegacyIntegralTypeEncoding -
3558/// Another legacy compatibility encoding: 32-bit longs are encoded as
3559/// 'l' or 'L' , but not always.  For typedefs, we need to use
3560/// 'i' or 'I' instead if encoding a struct field, or a pointer!
3561///
3562void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
3563  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
3564    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
3565      if (BT->getKind() == BuiltinType::ULong &&
3566          ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3567        PointeeTy = UnsignedIntTy;
3568      else
3569        if (BT->getKind() == BuiltinType::Long &&
3570            ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3571          PointeeTy = IntTy;
3572    }
3573  }
3574}
3575
3576void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
3577                                        const FieldDecl *Field) {
3578  // We follow the behavior of gcc, expanding structures which are
3579  // directly pointed to, and expanding embedded structures. Note that
3580  // these rules are sufficient to prevent recursive encoding of the
3581  // same type.
3582  getObjCEncodingForTypeImpl(T, S, true, true, Field,
3583                             true /* outermost type */);
3584}
3585
3586static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
3587    switch (T->getAs<BuiltinType>()->getKind()) {
3588    default: assert(0 && "Unhandled builtin type kind");
3589    case BuiltinType::Void:       return 'v';
3590    case BuiltinType::Bool:       return 'B';
3591    case BuiltinType::Char_U:
3592    case BuiltinType::UChar:      return 'C';
3593    case BuiltinType::UShort:     return 'S';
3594    case BuiltinType::UInt:       return 'I';
3595    case BuiltinType::ULong:
3596        return
3597          (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'L' : 'Q';
3598    case BuiltinType::UInt128:    return 'T';
3599    case BuiltinType::ULongLong:  return 'Q';
3600    case BuiltinType::Char_S:
3601    case BuiltinType::SChar:      return 'c';
3602    case BuiltinType::Short:      return 's';
3603    case BuiltinType::WChar:
3604    case BuiltinType::Int:        return 'i';
3605    case BuiltinType::Long:
3606      return
3607        (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'l' : 'q';
3608    case BuiltinType::LongLong:   return 'q';
3609    case BuiltinType::Int128:     return 't';
3610    case BuiltinType::Float:      return 'f';
3611    case BuiltinType::Double:     return 'd';
3612    case BuiltinType::LongDouble: return 'd';
3613    }
3614}
3615
3616static void EncodeBitField(const ASTContext *Context, std::string& S,
3617                           QualType T, const FieldDecl *FD) {
3618  const Expr *E = FD->getBitWidth();
3619  assert(E && "bitfield width not there - getObjCEncodingForTypeImpl");
3620  ASTContext *Ctx = const_cast<ASTContext*>(Context);
3621  S += 'b';
3622  // The NeXT runtime encodes bit fields as b followed by the number of bits.
3623  // The GNU runtime requires more information; bitfields are encoded as b,
3624  // then the offset (in bits) of the first element, then the type of the
3625  // bitfield, then the size in bits.  For example, in this structure:
3626  //
3627  // struct
3628  // {
3629  //    int integer;
3630  //    int flags:2;
3631  // };
3632  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
3633  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
3634  // information is not especially sensible, but we're stuck with it for
3635  // compatibility with GCC, although providing it breaks anything that
3636  // actually uses runtime introspection and wants to work on both runtimes...
3637  if (!Ctx->getLangOptions().NeXTRuntime) {
3638    const RecordDecl *RD = FD->getParent();
3639    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
3640    // FIXME: This same linear search is also used in ExprConstant - it might
3641    // be better if the FieldDecl stored its offset.  We'd be increasing the
3642    // size of the object slightly, but saving some time every time it is used.
3643    unsigned i = 0;
3644    for (RecordDecl::field_iterator Field = RD->field_begin(),
3645                                 FieldEnd = RD->field_end();
3646         Field != FieldEnd; (void)++Field, ++i) {
3647      if (*Field == FD)
3648        break;
3649    }
3650    S += llvm::utostr(RL.getFieldOffset(i));
3651    S += ObjCEncodingForPrimitiveKind(Context, T);
3652  }
3653  unsigned N = E->EvaluateAsInt(*Ctx).getZExtValue();
3654  S += llvm::utostr(N);
3655}
3656
3657// FIXME: Use SmallString for accumulating string.
3658void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
3659                                            bool ExpandPointedToStructures,
3660                                            bool ExpandStructures,
3661                                            const FieldDecl *FD,
3662                                            bool OutermostType,
3663                                            bool EncodingProperty) {
3664  if (T->getAs<BuiltinType>()) {
3665    if (FD && FD->isBitField())
3666      return EncodeBitField(this, S, T, FD);
3667    S += ObjCEncodingForPrimitiveKind(this, T);
3668    return;
3669  }
3670
3671  if (const ComplexType *CT = T->getAs<ComplexType>()) {
3672    S += 'j';
3673    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
3674                               false);
3675    return;
3676  }
3677
3678  // encoding for pointer or r3eference types.
3679  QualType PointeeTy;
3680  if (const PointerType *PT = T->getAs<PointerType>()) {
3681    if (PT->isObjCSelType()) {
3682      S += ':';
3683      return;
3684    }
3685    PointeeTy = PT->getPointeeType();
3686  }
3687  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3688    PointeeTy = RT->getPointeeType();
3689  if (!PointeeTy.isNull()) {
3690    bool isReadOnly = false;
3691    // For historical/compatibility reasons, the read-only qualifier of the
3692    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
3693    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
3694    // Also, do not emit the 'r' for anything but the outermost type!
3695    if (isa<TypedefType>(T.getTypePtr())) {
3696      if (OutermostType && T.isConstQualified()) {
3697        isReadOnly = true;
3698        S += 'r';
3699      }
3700    } else if (OutermostType) {
3701      QualType P = PointeeTy;
3702      while (P->getAs<PointerType>())
3703        P = P->getAs<PointerType>()->getPointeeType();
3704      if (P.isConstQualified()) {
3705        isReadOnly = true;
3706        S += 'r';
3707      }
3708    }
3709    if (isReadOnly) {
3710      // Another legacy compatibility encoding. Some ObjC qualifier and type
3711      // combinations need to be rearranged.
3712      // Rewrite "in const" from "nr" to "rn"
3713      if (llvm::StringRef(S).endswith("nr"))
3714        S.replace(S.end()-2, S.end(), "rn");
3715    }
3716
3717    if (PointeeTy->isCharType()) {
3718      // char pointer types should be encoded as '*' unless it is a
3719      // type that has been typedef'd to 'BOOL'.
3720      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
3721        S += '*';
3722        return;
3723      }
3724    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
3725      // GCC binary compat: Need to convert "struct objc_class *" to "#".
3726      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
3727        S += '#';
3728        return;
3729      }
3730      // GCC binary compat: Need to convert "struct objc_object *" to "@".
3731      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
3732        S += '@';
3733        return;
3734      }
3735      // fall through...
3736    }
3737    S += '^';
3738    getLegacyIntegralTypeEncoding(PointeeTy);
3739
3740    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
3741                               NULL);
3742    return;
3743  }
3744
3745  if (const ArrayType *AT =
3746      // Ignore type qualifiers etc.
3747        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
3748    if (isa<IncompleteArrayType>(AT)) {
3749      // Incomplete arrays are encoded as a pointer to the array element.
3750      S += '^';
3751
3752      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3753                                 false, ExpandStructures, FD);
3754    } else {
3755      S += '[';
3756
3757      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
3758        S += llvm::utostr(CAT->getSize().getZExtValue());
3759      else {
3760        //Variable length arrays are encoded as a regular array with 0 elements.
3761        assert(isa<VariableArrayType>(AT) && "Unknown array type!");
3762        S += '0';
3763      }
3764
3765      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3766                                 false, ExpandStructures, FD);
3767      S += ']';
3768    }
3769    return;
3770  }
3771
3772  if (T->getAs<FunctionType>()) {
3773    S += '?';
3774    return;
3775  }
3776
3777  if (const RecordType *RTy = T->getAs<RecordType>()) {
3778    RecordDecl *RDecl = RTy->getDecl();
3779    S += RDecl->isUnion() ? '(' : '{';
3780    // Anonymous structures print as '?'
3781    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
3782      S += II->getName();
3783      if (ClassTemplateSpecializationDecl *Spec
3784          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
3785        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
3786        std::string TemplateArgsStr
3787          = TemplateSpecializationType::PrintTemplateArgumentList(
3788                                            TemplateArgs.getFlatArgumentList(),
3789                                            TemplateArgs.flat_size(),
3790                                            (*this).PrintingPolicy);
3791
3792        S += TemplateArgsStr;
3793      }
3794    } else {
3795      S += '?';
3796    }
3797    if (ExpandStructures) {
3798      S += '=';
3799      for (RecordDecl::field_iterator Field = RDecl->field_begin(),
3800                                   FieldEnd = RDecl->field_end();
3801           Field != FieldEnd; ++Field) {
3802        if (FD) {
3803          S += '"';
3804          S += Field->getNameAsString();
3805          S += '"';
3806        }
3807
3808        // Special case bit-fields.
3809        if (Field->isBitField()) {
3810          getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
3811                                     (*Field));
3812        } else {
3813          QualType qt = Field->getType();
3814          getLegacyIntegralTypeEncoding(qt);
3815          getObjCEncodingForTypeImpl(qt, S, false, true,
3816                                     FD);
3817        }
3818      }
3819    }
3820    S += RDecl->isUnion() ? ')' : '}';
3821    return;
3822  }
3823
3824  if (T->isEnumeralType()) {
3825    if (FD && FD->isBitField())
3826      EncodeBitField(this, S, T, FD);
3827    else
3828      S += 'i';
3829    return;
3830  }
3831
3832  if (T->isBlockPointerType()) {
3833    S += "@?"; // Unlike a pointer-to-function, which is "^?".
3834    return;
3835  }
3836
3837  // Ignore protocol qualifiers when mangling at this level.
3838  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
3839    T = OT->getBaseType();
3840
3841  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
3842    // @encode(class_name)
3843    ObjCInterfaceDecl *OI = OIT->getDecl();
3844    S += '{';
3845    const IdentifierInfo *II = OI->getIdentifier();
3846    S += II->getName();
3847    S += '=';
3848    llvm::SmallVector<FieldDecl*, 32> RecFields;
3849    CollectObjCIvars(OI, RecFields);
3850    for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
3851      if (RecFields[i]->isBitField())
3852        getObjCEncodingForTypeImpl(RecFields[i]->getType(), S, false, true,
3853                                   RecFields[i]);
3854      else
3855        getObjCEncodingForTypeImpl(RecFields[i]->getType(), S, false, true,
3856                                   FD);
3857    }
3858    S += '}';
3859    return;
3860  }
3861
3862  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
3863    if (OPT->isObjCIdType()) {
3864      S += '@';
3865      return;
3866    }
3867
3868    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
3869      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
3870      // Since this is a binary compatibility issue, need to consult with runtime
3871      // folks. Fortunately, this is a *very* obsure construct.
3872      S += '#';
3873      return;
3874    }
3875
3876    if (OPT->isObjCQualifiedIdType()) {
3877      getObjCEncodingForTypeImpl(getObjCIdType(), S,
3878                                 ExpandPointedToStructures,
3879                                 ExpandStructures, FD);
3880      if (FD || EncodingProperty) {
3881        // Note that we do extended encoding of protocol qualifer list
3882        // Only when doing ivar or property encoding.
3883        S += '"';
3884        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3885             E = OPT->qual_end(); I != E; ++I) {
3886          S += '<';
3887          S += (*I)->getNameAsString();
3888          S += '>';
3889        }
3890        S += '"';
3891      }
3892      return;
3893    }
3894
3895    QualType PointeeTy = OPT->getPointeeType();
3896    if (!EncodingProperty &&
3897        isa<TypedefType>(PointeeTy.getTypePtr())) {
3898      // Another historical/compatibility reason.
3899      // We encode the underlying type which comes out as
3900      // {...};
3901      S += '^';
3902      getObjCEncodingForTypeImpl(PointeeTy, S,
3903                                 false, ExpandPointedToStructures,
3904                                 NULL);
3905      return;
3906    }
3907
3908    S += '@';
3909    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
3910      S += '"';
3911      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
3912      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3913           E = OPT->qual_end(); I != E; ++I) {
3914        S += '<';
3915        S += (*I)->getNameAsString();
3916        S += '>';
3917      }
3918      S += '"';
3919    }
3920    return;
3921  }
3922
3923  // gcc just blithely ignores member pointers.
3924  // TODO: maybe there should be a mangling for these
3925  if (T->getAs<MemberPointerType>())
3926    return;
3927
3928  assert(0 && "@encode for type not implemented!");
3929}
3930
3931void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
3932                                                 std::string& S) const {
3933  if (QT & Decl::OBJC_TQ_In)
3934    S += 'n';
3935  if (QT & Decl::OBJC_TQ_Inout)
3936    S += 'N';
3937  if (QT & Decl::OBJC_TQ_Out)
3938    S += 'o';
3939  if (QT & Decl::OBJC_TQ_Bycopy)
3940    S += 'O';
3941  if (QT & Decl::OBJC_TQ_Byref)
3942    S += 'R';
3943  if (QT & Decl::OBJC_TQ_Oneway)
3944    S += 'V';
3945}
3946
3947void ASTContext::setBuiltinVaListType(QualType T) {
3948  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
3949
3950  BuiltinVaListType = T;
3951}
3952
3953void ASTContext::setObjCIdType(QualType T) {
3954  ObjCIdTypedefType = T;
3955}
3956
3957void ASTContext::setObjCSelType(QualType T) {
3958  ObjCSelTypedefType = T;
3959}
3960
3961void ASTContext::setObjCProtoType(QualType QT) {
3962  ObjCProtoType = QT;
3963}
3964
3965void ASTContext::setObjCClassType(QualType T) {
3966  ObjCClassTypedefType = T;
3967}
3968
3969void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
3970  assert(ObjCConstantStringType.isNull() &&
3971         "'NSConstantString' type already set!");
3972
3973  ObjCConstantStringType = getObjCInterfaceType(Decl);
3974}
3975
3976/// \brief Retrieve the template name that corresponds to a non-empty
3977/// lookup.
3978TemplateName ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
3979                                                   UnresolvedSetIterator End) {
3980  unsigned size = End - Begin;
3981  assert(size > 1 && "set is not overloaded!");
3982
3983  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
3984                          size * sizeof(FunctionTemplateDecl*));
3985  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
3986
3987  NamedDecl **Storage = OT->getStorage();
3988  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
3989    NamedDecl *D = *I;
3990    assert(isa<FunctionTemplateDecl>(D) ||
3991           (isa<UsingShadowDecl>(D) &&
3992            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
3993    *Storage++ = D;
3994  }
3995
3996  return TemplateName(OT);
3997}
3998
3999/// \brief Retrieve the template name that represents a qualified
4000/// template name such as \c std::vector.
4001TemplateName ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4002                                                  bool TemplateKeyword,
4003                                                  TemplateDecl *Template) {
4004  // FIXME: Canonicalization?
4005  llvm::FoldingSetNodeID ID;
4006  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4007
4008  void *InsertPos = 0;
4009  QualifiedTemplateName *QTN =
4010    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4011  if (!QTN) {
4012    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4013    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4014  }
4015
4016  return TemplateName(QTN);
4017}
4018
4019/// \brief Retrieve the template name that represents a dependent
4020/// template name such as \c MetaFun::template apply.
4021TemplateName ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4022                                                  const IdentifierInfo *Name) {
4023  assert((!NNS || NNS->isDependent()) &&
4024         "Nested name specifier must be dependent");
4025
4026  llvm::FoldingSetNodeID ID;
4027  DependentTemplateName::Profile(ID, NNS, Name);
4028
4029  void *InsertPos = 0;
4030  DependentTemplateName *QTN =
4031    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4032
4033  if (QTN)
4034    return TemplateName(QTN);
4035
4036  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4037  if (CanonNNS == NNS) {
4038    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4039  } else {
4040    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4041    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4042    DependentTemplateName *CheckQTN =
4043      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4044    assert(!CheckQTN && "Dependent type name canonicalization broken");
4045    (void)CheckQTN;
4046  }
4047
4048  DependentTemplateNames.InsertNode(QTN, InsertPos);
4049  return TemplateName(QTN);
4050}
4051
4052/// \brief Retrieve the template name that represents a dependent
4053/// template name such as \c MetaFun::template operator+.
4054TemplateName
4055ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4056                                     OverloadedOperatorKind Operator) {
4057  assert((!NNS || NNS->isDependent()) &&
4058         "Nested name specifier must be dependent");
4059
4060  llvm::FoldingSetNodeID ID;
4061  DependentTemplateName::Profile(ID, NNS, Operator);
4062
4063  void *InsertPos = 0;
4064  DependentTemplateName *QTN
4065    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4066
4067  if (QTN)
4068    return TemplateName(QTN);
4069
4070  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4071  if (CanonNNS == NNS) {
4072    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4073  } else {
4074    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4075    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4076
4077    DependentTemplateName *CheckQTN
4078      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4079    assert(!CheckQTN && "Dependent template name canonicalization broken");
4080    (void)CheckQTN;
4081  }
4082
4083  DependentTemplateNames.InsertNode(QTN, InsertPos);
4084  return TemplateName(QTN);
4085}
4086
4087/// getFromTargetType - Given one of the integer types provided by
4088/// TargetInfo, produce the corresponding type. The unsigned @p Type
4089/// is actually a value of type @c TargetInfo::IntType.
4090CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4091  switch (Type) {
4092  case TargetInfo::NoInt: return CanQualType();
4093  case TargetInfo::SignedShort: return ShortTy;
4094  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4095  case TargetInfo::SignedInt: return IntTy;
4096  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4097  case TargetInfo::SignedLong: return LongTy;
4098  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4099  case TargetInfo::SignedLongLong: return LongLongTy;
4100  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4101  }
4102
4103  assert(false && "Unhandled TargetInfo::IntType value");
4104  return CanQualType();
4105}
4106
4107//===----------------------------------------------------------------------===//
4108//                        Type Predicates.
4109//===----------------------------------------------------------------------===//
4110
4111/// isObjCNSObjectType - Return true if this is an NSObject object using
4112/// NSObject attribute on a c-style pointer type.
4113/// FIXME - Make it work directly on types.
4114/// FIXME: Move to Type.
4115///
4116bool ASTContext::isObjCNSObjectType(QualType Ty) const {
4117  if (TypedefType *TDT = dyn_cast<TypedefType>(Ty)) {
4118    if (TypedefDecl *TD = TDT->getDecl())
4119      if (TD->getAttr<ObjCNSObjectAttr>())
4120        return true;
4121  }
4122  return false;
4123}
4124
4125/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4126/// garbage collection attribute.
4127///
4128Qualifiers::GC ASTContext::getObjCGCAttrKind(const QualType &Ty) const {
4129  Qualifiers::GC GCAttrs = Qualifiers::GCNone;
4130  if (getLangOptions().ObjC1 &&
4131      getLangOptions().getGCMode() != LangOptions::NonGC) {
4132    GCAttrs = Ty.getObjCGCAttr();
4133    // Default behavious under objective-c's gc is for objective-c pointers
4134    // (or pointers to them) be treated as though they were declared
4135    // as __strong.
4136    if (GCAttrs == Qualifiers::GCNone) {
4137      if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4138        GCAttrs = Qualifiers::Strong;
4139      else if (Ty->isPointerType())
4140        return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4141    }
4142    // Non-pointers have none gc'able attribute regardless of the attribute
4143    // set on them.
4144    else if (!Ty->isAnyPointerType() && !Ty->isBlockPointerType())
4145      return Qualifiers::GCNone;
4146  }
4147  return GCAttrs;
4148}
4149
4150//===----------------------------------------------------------------------===//
4151//                        Type Compatibility Testing
4152//===----------------------------------------------------------------------===//
4153
4154/// areCompatVectorTypes - Return true if the two specified vector types are
4155/// compatible.
4156static bool areCompatVectorTypes(const VectorType *LHS,
4157                                 const VectorType *RHS) {
4158  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
4159  return LHS->getElementType() == RHS->getElementType() &&
4160         LHS->getNumElements() == RHS->getNumElements();
4161}
4162
4163//===----------------------------------------------------------------------===//
4164// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
4165//===----------------------------------------------------------------------===//
4166
4167/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
4168/// inheritance hierarchy of 'rProto'.
4169bool ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
4170                                                ObjCProtocolDecl *rProto) {
4171  if (lProto == rProto)
4172    return true;
4173  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
4174       E = rProto->protocol_end(); PI != E; ++PI)
4175    if (ProtocolCompatibleWithProtocol(lProto, *PI))
4176      return true;
4177  return false;
4178}
4179
4180/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
4181/// return true if lhs's protocols conform to rhs's protocol; false
4182/// otherwise.
4183bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
4184  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
4185    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
4186  return false;
4187}
4188
4189/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
4190/// ObjCQualifiedIDType.
4191bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
4192                                                   bool compare) {
4193  // Allow id<P..> and an 'id' or void* type in all cases.
4194  if (lhs->isVoidPointerType() ||
4195      lhs->isObjCIdType() || lhs->isObjCClassType())
4196    return true;
4197  else if (rhs->isVoidPointerType() ||
4198           rhs->isObjCIdType() || rhs->isObjCClassType())
4199    return true;
4200
4201  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
4202    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4203
4204    if (!rhsOPT) return false;
4205
4206    if (rhsOPT->qual_empty()) {
4207      // If the RHS is a unqualified interface pointer "NSString*",
4208      // make sure we check the class hierarchy.
4209      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4210        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4211             E = lhsQID->qual_end(); I != E; ++I) {
4212          // when comparing an id<P> on lhs with a static type on rhs,
4213          // see if static class implements all of id's protocols, directly or
4214          // through its super class and categories.
4215          if (!rhsID->ClassImplementsProtocol(*I, true))
4216            return false;
4217        }
4218      }
4219      // If there are no qualifiers and no interface, we have an 'id'.
4220      return true;
4221    }
4222    // Both the right and left sides have qualifiers.
4223    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4224         E = lhsQID->qual_end(); I != E; ++I) {
4225      ObjCProtocolDecl *lhsProto = *I;
4226      bool match = false;
4227
4228      // when comparing an id<P> on lhs with a static type on rhs,
4229      // see if static class implements all of id's protocols, directly or
4230      // through its super class and categories.
4231      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4232           E = rhsOPT->qual_end(); J != E; ++J) {
4233        ObjCProtocolDecl *rhsProto = *J;
4234        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4235            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4236          match = true;
4237          break;
4238        }
4239      }
4240      // If the RHS is a qualified interface pointer "NSString<P>*",
4241      // make sure we check the class hierarchy.
4242      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4243        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4244             E = lhsQID->qual_end(); I != E; ++I) {
4245          // when comparing an id<P> on lhs with a static type on rhs,
4246          // see if static class implements all of id's protocols, directly or
4247          // through its super class and categories.
4248          if (rhsID->ClassImplementsProtocol(*I, true)) {
4249            match = true;
4250            break;
4251          }
4252        }
4253      }
4254      if (!match)
4255        return false;
4256    }
4257
4258    return true;
4259  }
4260
4261  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
4262  assert(rhsQID && "One of the LHS/RHS should be id<x>");
4263
4264  if (const ObjCObjectPointerType *lhsOPT =
4265        lhs->getAsObjCInterfacePointerType()) {
4266    if (lhsOPT->qual_empty()) {
4267      bool match = false;
4268      if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
4269        for (ObjCObjectPointerType::qual_iterator I = rhsQID->qual_begin(),
4270             E = rhsQID->qual_end(); I != E; ++I) {
4271          // when comparing an id<P> on lhs with a static type on rhs,
4272          // see if static class implements all of id's protocols, directly or
4273          // through its super class and categories.
4274          if (lhsID->ClassImplementsProtocol(*I, true)) {
4275            match = true;
4276            break;
4277          }
4278        }
4279        if (!match)
4280          return false;
4281      }
4282      return true;
4283    }
4284    // Both the right and left sides have qualifiers.
4285    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
4286         E = lhsOPT->qual_end(); I != E; ++I) {
4287      ObjCProtocolDecl *lhsProto = *I;
4288      bool match = false;
4289
4290      // when comparing an id<P> on lhs with a static type on rhs,
4291      // see if static class implements all of id's protocols, directly or
4292      // through its super class and categories.
4293      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4294           E = rhsQID->qual_end(); J != E; ++J) {
4295        ObjCProtocolDecl *rhsProto = *J;
4296        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4297            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4298          match = true;
4299          break;
4300        }
4301      }
4302      if (!match)
4303        return false;
4304    }
4305    return true;
4306  }
4307  return false;
4308}
4309
4310/// canAssignObjCInterfaces - Return true if the two interface types are
4311/// compatible for assignment from RHS to LHS.  This handles validation of any
4312/// protocol qualifiers on the LHS or RHS.
4313///
4314bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
4315                                         const ObjCObjectPointerType *RHSOPT) {
4316  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4317  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4318
4319  // If either type represents the built-in 'id' or 'Class' types, return true.
4320  if (LHS->isObjCUnqualifiedIdOrClass() ||
4321      RHS->isObjCUnqualifiedIdOrClass())
4322    return true;
4323
4324  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
4325    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4326                                             QualType(RHSOPT,0),
4327                                             false);
4328
4329  // If we have 2 user-defined types, fall into that path.
4330  if (LHS->getInterface() && RHS->getInterface())
4331    return canAssignObjCInterfaces(LHS, RHS);
4332
4333  return false;
4334}
4335
4336/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
4337/// for providing type-safty for objective-c pointers used to pass/return
4338/// arguments in block literals. When passed as arguments, passing 'A*' where
4339/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
4340/// not OK. For the return type, the opposite is not OK.
4341bool ASTContext::canAssignObjCInterfacesInBlockPointer(
4342                                         const ObjCObjectPointerType *LHSOPT,
4343                                         const ObjCObjectPointerType *RHSOPT) {
4344  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
4345    return true;
4346
4347  if (LHSOPT->isObjCBuiltinType()) {
4348    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
4349  }
4350
4351  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
4352    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4353                                             QualType(RHSOPT,0),
4354                                             false);
4355
4356  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
4357  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
4358  if (LHS && RHS)  { // We have 2 user-defined types.
4359    if (LHS != RHS) {
4360      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
4361        return false;
4362      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
4363        return true;
4364    }
4365    else
4366      return true;
4367  }
4368  return false;
4369}
4370
4371/// getIntersectionOfProtocols - This routine finds the intersection of set
4372/// of protocols inherited from two distinct objective-c pointer objects.
4373/// It is used to build composite qualifier list of the composite type of
4374/// the conditional expression involving two objective-c pointer objects.
4375static
4376void getIntersectionOfProtocols(ASTContext &Context,
4377                                const ObjCObjectPointerType *LHSOPT,
4378                                const ObjCObjectPointerType *RHSOPT,
4379      llvm::SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
4380
4381  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4382  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4383  assert(LHS->getInterface() && "LHS must have an interface base");
4384  assert(RHS->getInterface() && "RHS must have an interface base");
4385
4386  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
4387  unsigned LHSNumProtocols = LHS->getNumProtocols();
4388  if (LHSNumProtocols > 0)
4389    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
4390  else {
4391    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4392    Context.CollectInheritedProtocols(LHS->getInterface(),
4393                                      LHSInheritedProtocols);
4394    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
4395                                LHSInheritedProtocols.end());
4396  }
4397
4398  unsigned RHSNumProtocols = RHS->getNumProtocols();
4399  if (RHSNumProtocols > 0) {
4400    ObjCProtocolDecl **RHSProtocols =
4401      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
4402    for (unsigned i = 0; i < RHSNumProtocols; ++i)
4403      if (InheritedProtocolSet.count(RHSProtocols[i]))
4404        IntersectionOfProtocols.push_back(RHSProtocols[i]);
4405  }
4406  else {
4407    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
4408    Context.CollectInheritedProtocols(RHS->getInterface(),
4409                                      RHSInheritedProtocols);
4410    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4411         RHSInheritedProtocols.begin(),
4412         E = RHSInheritedProtocols.end(); I != E; ++I)
4413      if (InheritedProtocolSet.count((*I)))
4414        IntersectionOfProtocols.push_back((*I));
4415  }
4416}
4417
4418/// areCommonBaseCompatible - Returns common base class of the two classes if
4419/// one found. Note that this is O'2 algorithm. But it will be called as the
4420/// last type comparison in a ?-exp of ObjC pointer types before a
4421/// warning is issued. So, its invokation is extremely rare.
4422QualType ASTContext::areCommonBaseCompatible(
4423                                          const ObjCObjectPointerType *Lptr,
4424                                          const ObjCObjectPointerType *Rptr) {
4425  const ObjCObjectType *LHS = Lptr->getObjectType();
4426  const ObjCObjectType *RHS = Rptr->getObjectType();
4427  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
4428  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
4429  if (!LDecl || !RDecl)
4430    return QualType();
4431
4432  while ((LDecl = LDecl->getSuperClass())) {
4433    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
4434    if (canAssignObjCInterfaces(LHS, RHS)) {
4435      llvm::SmallVector<ObjCProtocolDecl *, 8> Protocols;
4436      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
4437
4438      QualType Result = QualType(LHS, 0);
4439      if (!Protocols.empty())
4440        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
4441      Result = getObjCObjectPointerType(Result);
4442      return Result;
4443    }
4444  }
4445
4446  return QualType();
4447}
4448
4449bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
4450                                         const ObjCObjectType *RHS) {
4451  assert(LHS->getInterface() && "LHS is not an interface type");
4452  assert(RHS->getInterface() && "RHS is not an interface type");
4453
4454  // Verify that the base decls are compatible: the RHS must be a subclass of
4455  // the LHS.
4456  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
4457    return false;
4458
4459  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
4460  // protocol qualified at all, then we are good.
4461  if (LHS->getNumProtocols() == 0)
4462    return true;
4463
4464  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't, then it
4465  // isn't a superset.
4466  if (RHS->getNumProtocols() == 0)
4467    return true;  // FIXME: should return false!
4468
4469  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
4470                                     LHSPE = LHS->qual_end();
4471       LHSPI != LHSPE; LHSPI++) {
4472    bool RHSImplementsProtocol = false;
4473
4474    // If the RHS doesn't implement the protocol on the left, the types
4475    // are incompatible.
4476    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
4477                                       RHSPE = RHS->qual_end();
4478         RHSPI != RHSPE; RHSPI++) {
4479      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
4480        RHSImplementsProtocol = true;
4481        break;
4482      }
4483    }
4484    // FIXME: For better diagnostics, consider passing back the protocol name.
4485    if (!RHSImplementsProtocol)
4486      return false;
4487  }
4488  // The RHS implements all protocols listed on the LHS.
4489  return true;
4490}
4491
4492bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
4493  // get the "pointed to" types
4494  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
4495  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
4496
4497  if (!LHSOPT || !RHSOPT)
4498    return false;
4499
4500  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
4501         canAssignObjCInterfaces(RHSOPT, LHSOPT);
4502}
4503
4504/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
4505/// both shall have the identically qualified version of a compatible type.
4506/// C99 6.2.7p1: Two types have compatible types if their types are the
4507/// same. See 6.7.[2,3,5] for additional rules.
4508bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS) {
4509  if (getLangOptions().CPlusPlus)
4510    return hasSameType(LHS, RHS);
4511
4512  return !mergeTypes(LHS, RHS).isNull();
4513}
4514
4515bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
4516  return !mergeTypes(LHS, RHS, true).isNull();
4517}
4518
4519QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
4520                                        bool OfBlockPointer) {
4521  const FunctionType *lbase = lhs->getAs<FunctionType>();
4522  const FunctionType *rbase = rhs->getAs<FunctionType>();
4523  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
4524  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
4525  bool allLTypes = true;
4526  bool allRTypes = true;
4527
4528  // Check return type
4529  QualType retType;
4530  if (OfBlockPointer)
4531    retType = mergeTypes(rbase->getResultType(), lbase->getResultType(), true);
4532  else
4533   retType = mergeTypes(lbase->getResultType(), rbase->getResultType());
4534  if (retType.isNull()) return QualType();
4535  if (getCanonicalType(retType) != getCanonicalType(lbase->getResultType()))
4536    allLTypes = false;
4537  if (getCanonicalType(retType) != getCanonicalType(rbase->getResultType()))
4538    allRTypes = false;
4539  // FIXME: double check this
4540  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
4541  //                           rbase->getRegParmAttr() != 0 &&
4542  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
4543  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
4544  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
4545  unsigned RegParm = lbaseInfo.getRegParm() == 0 ? rbaseInfo.getRegParm() :
4546      lbaseInfo.getRegParm();
4547  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
4548  if (NoReturn != lbaseInfo.getNoReturn() ||
4549      RegParm != lbaseInfo.getRegParm())
4550    allLTypes = false;
4551  if (NoReturn != rbaseInfo.getNoReturn() ||
4552      RegParm != rbaseInfo.getRegParm())
4553    allRTypes = false;
4554  CallingConv lcc = lbaseInfo.getCC();
4555  CallingConv rcc = rbaseInfo.getCC();
4556  // Compatible functions must have compatible calling conventions
4557  if (!isSameCallConv(lcc, rcc))
4558    return QualType();
4559
4560  if (lproto && rproto) { // two C99 style function prototypes
4561    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
4562           "C++ shouldn't be here");
4563    unsigned lproto_nargs = lproto->getNumArgs();
4564    unsigned rproto_nargs = rproto->getNumArgs();
4565
4566    // Compatible functions must have the same number of arguments
4567    if (lproto_nargs != rproto_nargs)
4568      return QualType();
4569
4570    // Variadic and non-variadic functions aren't compatible
4571    if (lproto->isVariadic() != rproto->isVariadic())
4572      return QualType();
4573
4574    if (lproto->getTypeQuals() != rproto->getTypeQuals())
4575      return QualType();
4576
4577    // Check argument compatibility
4578    llvm::SmallVector<QualType, 10> types;
4579    for (unsigned i = 0; i < lproto_nargs; i++) {
4580      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
4581      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
4582      QualType argtype = mergeTypes(largtype, rargtype, OfBlockPointer);
4583      if (argtype.isNull()) return QualType();
4584      types.push_back(argtype);
4585      if (getCanonicalType(argtype) != getCanonicalType(largtype))
4586        allLTypes = false;
4587      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
4588        allRTypes = false;
4589    }
4590    if (allLTypes) return lhs;
4591    if (allRTypes) return rhs;
4592    return getFunctionType(retType, types.begin(), types.size(),
4593                           lproto->isVariadic(), lproto->getTypeQuals(),
4594                           false, false, 0, 0,
4595                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4596  }
4597
4598  if (lproto) allRTypes = false;
4599  if (rproto) allLTypes = false;
4600
4601  const FunctionProtoType *proto = lproto ? lproto : rproto;
4602  if (proto) {
4603    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
4604    if (proto->isVariadic()) return QualType();
4605    // Check that the types are compatible with the types that
4606    // would result from default argument promotions (C99 6.7.5.3p15).
4607    // The only types actually affected are promotable integer
4608    // types and floats, which would be passed as a different
4609    // type depending on whether the prototype is visible.
4610    unsigned proto_nargs = proto->getNumArgs();
4611    for (unsigned i = 0; i < proto_nargs; ++i) {
4612      QualType argTy = proto->getArgType(i);
4613
4614      // Look at the promotion type of enum types, since that is the type used
4615      // to pass enum values.
4616      if (const EnumType *Enum = argTy->getAs<EnumType>())
4617        argTy = Enum->getDecl()->getPromotionType();
4618
4619      if (argTy->isPromotableIntegerType() ||
4620          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
4621        return QualType();
4622    }
4623
4624    if (allLTypes) return lhs;
4625    if (allRTypes) return rhs;
4626    return getFunctionType(retType, proto->arg_type_begin(),
4627                           proto->getNumArgs(), proto->isVariadic(),
4628                           proto->getTypeQuals(),
4629                           false, false, 0, 0,
4630                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4631  }
4632
4633  if (allLTypes) return lhs;
4634  if (allRTypes) return rhs;
4635  FunctionType::ExtInfo Info(NoReturn, RegParm, lcc);
4636  return getFunctionNoProtoType(retType, Info);
4637}
4638
4639QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
4640                                bool OfBlockPointer) {
4641  // C++ [expr]: If an expression initially has the type "reference to T", the
4642  // type is adjusted to "T" prior to any further analysis, the expression
4643  // designates the object or function denoted by the reference, and the
4644  // expression is an lvalue unless the reference is an rvalue reference and
4645  // the expression is a function call (possibly inside parentheses).
4646  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
4647  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
4648
4649  QualType LHSCan = getCanonicalType(LHS),
4650           RHSCan = getCanonicalType(RHS);
4651
4652  // If two types are identical, they are compatible.
4653  if (LHSCan == RHSCan)
4654    return LHS;
4655
4656  // If the qualifiers are different, the types aren't compatible... mostly.
4657  Qualifiers LQuals = LHSCan.getLocalQualifiers();
4658  Qualifiers RQuals = RHSCan.getLocalQualifiers();
4659  if (LQuals != RQuals) {
4660    // If any of these qualifiers are different, we have a type
4661    // mismatch.
4662    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
4663        LQuals.getAddressSpace() != RQuals.getAddressSpace())
4664      return QualType();
4665
4666    // Exactly one GC qualifier difference is allowed: __strong is
4667    // okay if the other type has no GC qualifier but is an Objective
4668    // C object pointer (i.e. implicitly strong by default).  We fix
4669    // this by pretending that the unqualified type was actually
4670    // qualified __strong.
4671    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
4672    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
4673    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
4674
4675    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
4676      return QualType();
4677
4678    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
4679      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
4680    }
4681    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
4682      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
4683    }
4684    return QualType();
4685  }
4686
4687  // Okay, qualifiers are equal.
4688
4689  Type::TypeClass LHSClass = LHSCan->getTypeClass();
4690  Type::TypeClass RHSClass = RHSCan->getTypeClass();
4691
4692  // We want to consider the two function types to be the same for these
4693  // comparisons, just force one to the other.
4694  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
4695  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
4696
4697  // Same as above for arrays
4698  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
4699    LHSClass = Type::ConstantArray;
4700  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
4701    RHSClass = Type::ConstantArray;
4702
4703  // ObjCInterfaces are just specialized ObjCObjects.
4704  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
4705  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
4706
4707  // Canonicalize ExtVector -> Vector.
4708  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
4709  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
4710
4711  // If the canonical type classes don't match.
4712  if (LHSClass != RHSClass) {
4713    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
4714    // a signed integer type, or an unsigned integer type.
4715    // Compatibility is based on the underlying type, not the promotion
4716    // type.
4717    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
4718      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
4719        return RHS;
4720    }
4721    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
4722      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
4723        return LHS;
4724    }
4725
4726    return QualType();
4727  }
4728
4729  // The canonical type classes match.
4730  switch (LHSClass) {
4731#define TYPE(Class, Base)
4732#define ABSTRACT_TYPE(Class, Base)
4733#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
4734#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
4735#define DEPENDENT_TYPE(Class, Base) case Type::Class:
4736#include "clang/AST/TypeNodes.def"
4737    assert(false && "Non-canonical and dependent types shouldn't get here");
4738    return QualType();
4739
4740  case Type::LValueReference:
4741  case Type::RValueReference:
4742  case Type::MemberPointer:
4743    assert(false && "C++ should never be in mergeTypes");
4744    return QualType();
4745
4746  case Type::ObjCInterface:
4747  case Type::IncompleteArray:
4748  case Type::VariableArray:
4749  case Type::FunctionProto:
4750  case Type::ExtVector:
4751    assert(false && "Types are eliminated above");
4752    return QualType();
4753
4754  case Type::Pointer:
4755  {
4756    // Merge two pointer types, while trying to preserve typedef info
4757    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
4758    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
4759    QualType ResultType = mergeTypes(LHSPointee, RHSPointee);
4760    if (ResultType.isNull()) return QualType();
4761    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
4762      return LHS;
4763    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
4764      return RHS;
4765    return getPointerType(ResultType);
4766  }
4767  case Type::BlockPointer:
4768  {
4769    // Merge two block pointer types, while trying to preserve typedef info
4770    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
4771    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
4772    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer);
4773    if (ResultType.isNull()) return QualType();
4774    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
4775      return LHS;
4776    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
4777      return RHS;
4778    return getBlockPointerType(ResultType);
4779  }
4780  case Type::ConstantArray:
4781  {
4782    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
4783    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
4784    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
4785      return QualType();
4786
4787    QualType LHSElem = getAsArrayType(LHS)->getElementType();
4788    QualType RHSElem = getAsArrayType(RHS)->getElementType();
4789    QualType ResultType = mergeTypes(LHSElem, RHSElem);
4790    if (ResultType.isNull()) return QualType();
4791    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
4792      return LHS;
4793    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
4794      return RHS;
4795    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
4796                                          ArrayType::ArraySizeModifier(), 0);
4797    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
4798                                          ArrayType::ArraySizeModifier(), 0);
4799    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
4800    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
4801    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
4802      return LHS;
4803    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
4804      return RHS;
4805    if (LVAT) {
4806      // FIXME: This isn't correct! But tricky to implement because
4807      // the array's size has to be the size of LHS, but the type
4808      // has to be different.
4809      return LHS;
4810    }
4811    if (RVAT) {
4812      // FIXME: This isn't correct! But tricky to implement because
4813      // the array's size has to be the size of RHS, but the type
4814      // has to be different.
4815      return RHS;
4816    }
4817    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
4818    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
4819    return getIncompleteArrayType(ResultType,
4820                                  ArrayType::ArraySizeModifier(), 0);
4821  }
4822  case Type::FunctionNoProto:
4823    return mergeFunctionTypes(LHS, RHS, OfBlockPointer);
4824  case Type::Record:
4825  case Type::Enum:
4826    return QualType();
4827  case Type::Builtin:
4828    // Only exactly equal builtin types are compatible, which is tested above.
4829    return QualType();
4830  case Type::Complex:
4831    // Distinct complex types are incompatible.
4832    return QualType();
4833  case Type::Vector:
4834    // FIXME: The merged type should be an ExtVector!
4835    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
4836                             RHSCan->getAs<VectorType>()))
4837      return LHS;
4838    return QualType();
4839  case Type::ObjCObject: {
4840    // Check if the types are assignment compatible.
4841    // FIXME: This should be type compatibility, e.g. whether
4842    // "LHS x; RHS x;" at global scope is legal.
4843    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
4844    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
4845    if (canAssignObjCInterfaces(LHSIface, RHSIface))
4846      return LHS;
4847
4848    return QualType();
4849  }
4850  case Type::ObjCObjectPointer: {
4851    if (OfBlockPointer) {
4852      if (canAssignObjCInterfacesInBlockPointer(
4853                                          LHS->getAs<ObjCObjectPointerType>(),
4854                                          RHS->getAs<ObjCObjectPointerType>()))
4855      return LHS;
4856      return QualType();
4857    }
4858    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
4859                                RHS->getAs<ObjCObjectPointerType>()))
4860      return LHS;
4861
4862    return QualType();
4863    }
4864  }
4865
4866  return QualType();
4867}
4868
4869/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
4870/// 'RHS' attributes and returns the merged version; including for function
4871/// return types.
4872QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
4873  QualType LHSCan = getCanonicalType(LHS),
4874  RHSCan = getCanonicalType(RHS);
4875  // If two types are identical, they are compatible.
4876  if (LHSCan == RHSCan)
4877    return LHS;
4878  if (RHSCan->isFunctionType()) {
4879    if (!LHSCan->isFunctionType())
4880      return QualType();
4881    QualType OldReturnType =
4882      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
4883    QualType NewReturnType =
4884      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
4885    QualType ResReturnType =
4886      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
4887    if (ResReturnType.isNull())
4888      return QualType();
4889    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
4890      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
4891      // In either case, use OldReturnType to build the new function type.
4892      const FunctionType *F = LHS->getAs<FunctionType>();
4893      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
4894        FunctionType::ExtInfo Info = getFunctionExtInfo(LHS);
4895        QualType ResultType
4896          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
4897                                  FPT->getNumArgs(), FPT->isVariadic(),
4898                                  FPT->getTypeQuals(),
4899                                  FPT->hasExceptionSpec(),
4900                                  FPT->hasAnyExceptionSpec(),
4901                                  FPT->getNumExceptions(),
4902                                  FPT->exception_begin(),
4903                                  Info);
4904        return ResultType;
4905      }
4906    }
4907    return QualType();
4908  }
4909
4910  // If the qualifiers are different, the types can still be merged.
4911  Qualifiers LQuals = LHSCan.getLocalQualifiers();
4912  Qualifiers RQuals = RHSCan.getLocalQualifiers();
4913  if (LQuals != RQuals) {
4914    // If any of these qualifiers are different, we have a type mismatch.
4915    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
4916        LQuals.getAddressSpace() != RQuals.getAddressSpace())
4917      return QualType();
4918
4919    // Exactly one GC qualifier difference is allowed: __strong is
4920    // okay if the other type has no GC qualifier but is an Objective
4921    // C object pointer (i.e. implicitly strong by default).  We fix
4922    // this by pretending that the unqualified type was actually
4923    // qualified __strong.
4924    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
4925    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
4926    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
4927
4928    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
4929      return QualType();
4930
4931    if (GC_L == Qualifiers::Strong)
4932      return LHS;
4933    if (GC_R == Qualifiers::Strong)
4934      return RHS;
4935    return QualType();
4936  }
4937
4938  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
4939    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
4940    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
4941    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
4942    if (ResQT == LHSBaseQT)
4943      return LHS;
4944    if (ResQT == RHSBaseQT)
4945      return RHS;
4946  }
4947  return QualType();
4948}
4949
4950//===----------------------------------------------------------------------===//
4951//                         Integer Predicates
4952//===----------------------------------------------------------------------===//
4953
4954unsigned ASTContext::getIntWidth(QualType T) {
4955  if (T->isBooleanType())
4956    return 1;
4957  if (EnumType *ET = dyn_cast<EnumType>(T))
4958    T = ET->getDecl()->getIntegerType();
4959  // For builtin types, just use the standard type sizing method
4960  return (unsigned)getTypeSize(T);
4961}
4962
4963QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
4964  assert(T->isSignedIntegerType() && "Unexpected type");
4965
4966  // Turn <4 x signed int> -> <4 x unsigned int>
4967  if (const VectorType *VTy = T->getAs<VectorType>())
4968    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
4969             VTy->getNumElements(), VTy->getAltiVecSpecific());
4970
4971  // For enums, we return the unsigned version of the base type.
4972  if (const EnumType *ETy = T->getAs<EnumType>())
4973    T = ETy->getDecl()->getIntegerType();
4974
4975  const BuiltinType *BTy = T->getAs<BuiltinType>();
4976  assert(BTy && "Unexpected signed integer type");
4977  switch (BTy->getKind()) {
4978  case BuiltinType::Char_S:
4979  case BuiltinType::SChar:
4980    return UnsignedCharTy;
4981  case BuiltinType::Short:
4982    return UnsignedShortTy;
4983  case BuiltinType::Int:
4984    return UnsignedIntTy;
4985  case BuiltinType::Long:
4986    return UnsignedLongTy;
4987  case BuiltinType::LongLong:
4988    return UnsignedLongLongTy;
4989  case BuiltinType::Int128:
4990    return UnsignedInt128Ty;
4991  default:
4992    assert(0 && "Unexpected signed integer type");
4993    return QualType();
4994  }
4995}
4996
4997ExternalASTSource::~ExternalASTSource() { }
4998
4999void ExternalASTSource::PrintStats() { }
5000
5001
5002//===----------------------------------------------------------------------===//
5003//                          Builtin Type Computation
5004//===----------------------------------------------------------------------===//
5005
5006/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
5007/// pointer over the consumed characters.  This returns the resultant type.
5008static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
5009                                  ASTContext::GetBuiltinTypeError &Error,
5010                                  bool AllowTypeModifiers = true) {
5011  // Modifiers.
5012  int HowLong = 0;
5013  bool Signed = false, Unsigned = false;
5014
5015  // Read the modifiers first.
5016  bool Done = false;
5017  while (!Done) {
5018    switch (*Str++) {
5019    default: Done = true; --Str; break;
5020    case 'S':
5021      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
5022      assert(!Signed && "Can't use 'S' modifier multiple times!");
5023      Signed = true;
5024      break;
5025    case 'U':
5026      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
5027      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
5028      Unsigned = true;
5029      break;
5030    case 'L':
5031      assert(HowLong <= 2 && "Can't have LLLL modifier");
5032      ++HowLong;
5033      break;
5034    }
5035  }
5036
5037  QualType Type;
5038
5039  // Read the base type.
5040  switch (*Str++) {
5041  default: assert(0 && "Unknown builtin type letter!");
5042  case 'v':
5043    assert(HowLong == 0 && !Signed && !Unsigned &&
5044           "Bad modifiers used with 'v'!");
5045    Type = Context.VoidTy;
5046    break;
5047  case 'f':
5048    assert(HowLong == 0 && !Signed && !Unsigned &&
5049           "Bad modifiers used with 'f'!");
5050    Type = Context.FloatTy;
5051    break;
5052  case 'd':
5053    assert(HowLong < 2 && !Signed && !Unsigned &&
5054           "Bad modifiers used with 'd'!");
5055    if (HowLong)
5056      Type = Context.LongDoubleTy;
5057    else
5058      Type = Context.DoubleTy;
5059    break;
5060  case 's':
5061    assert(HowLong == 0 && "Bad modifiers used with 's'!");
5062    if (Unsigned)
5063      Type = Context.UnsignedShortTy;
5064    else
5065      Type = Context.ShortTy;
5066    break;
5067  case 'i':
5068    if (HowLong == 3)
5069      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
5070    else if (HowLong == 2)
5071      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
5072    else if (HowLong == 1)
5073      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
5074    else
5075      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
5076    break;
5077  case 'c':
5078    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
5079    if (Signed)
5080      Type = Context.SignedCharTy;
5081    else if (Unsigned)
5082      Type = Context.UnsignedCharTy;
5083    else
5084      Type = Context.CharTy;
5085    break;
5086  case 'b': // boolean
5087    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
5088    Type = Context.BoolTy;
5089    break;
5090  case 'z':  // size_t.
5091    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
5092    Type = Context.getSizeType();
5093    break;
5094  case 'F':
5095    Type = Context.getCFConstantStringType();
5096    break;
5097  case 'a':
5098    Type = Context.getBuiltinVaListType();
5099    assert(!Type.isNull() && "builtin va list type not initialized!");
5100    break;
5101  case 'A':
5102    // This is a "reference" to a va_list; however, what exactly
5103    // this means depends on how va_list is defined. There are two
5104    // different kinds of va_list: ones passed by value, and ones
5105    // passed by reference.  An example of a by-value va_list is
5106    // x86, where va_list is a char*. An example of by-ref va_list
5107    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
5108    // we want this argument to be a char*&; for x86-64, we want
5109    // it to be a __va_list_tag*.
5110    Type = Context.getBuiltinVaListType();
5111    assert(!Type.isNull() && "builtin va list type not initialized!");
5112    if (Type->isArrayType()) {
5113      Type = Context.getArrayDecayedType(Type);
5114    } else {
5115      Type = Context.getLValueReferenceType(Type);
5116    }
5117    break;
5118  case 'V': {
5119    char *End;
5120    unsigned NumElements = strtoul(Str, &End, 10);
5121    assert(End != Str && "Missing vector size");
5122
5123    Str = End;
5124
5125    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, false);
5126    // FIXME: Don't know what to do about AltiVec.
5127    Type = Context.getVectorType(ElementType, NumElements,
5128                                 VectorType::NotAltiVec);
5129    break;
5130  }
5131  case 'X': {
5132    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, false);
5133    Type = Context.getComplexType(ElementType);
5134    break;
5135  }
5136  case 'P':
5137    Type = Context.getFILEType();
5138    if (Type.isNull()) {
5139      Error = ASTContext::GE_Missing_stdio;
5140      return QualType();
5141    }
5142    break;
5143  case 'J':
5144    if (Signed)
5145      Type = Context.getsigjmp_bufType();
5146    else
5147      Type = Context.getjmp_bufType();
5148
5149    if (Type.isNull()) {
5150      Error = ASTContext::GE_Missing_setjmp;
5151      return QualType();
5152    }
5153    break;
5154  }
5155
5156  if (!AllowTypeModifiers)
5157    return Type;
5158
5159  Done = false;
5160  while (!Done) {
5161    switch (char c = *Str++) {
5162      default: Done = true; --Str; break;
5163      case '*':
5164      case '&':
5165        {
5166          // Both pointers and references can have their pointee types
5167          // qualified with an address space.
5168          char *End;
5169          unsigned AddrSpace = strtoul(Str, &End, 10);
5170          if (End != Str && AddrSpace != 0) {
5171            Type = Context.getAddrSpaceQualType(Type, AddrSpace);
5172            Str = End;
5173          }
5174        }
5175        if (c == '*')
5176          Type = Context.getPointerType(Type);
5177        else
5178          Type = Context.getLValueReferenceType(Type);
5179        break;
5180      // FIXME: There's no way to have a built-in with an rvalue ref arg.
5181      case 'C':
5182        Type = Type.withConst();
5183        break;
5184      case 'D':
5185        Type = Context.getVolatileType(Type);
5186        break;
5187    }
5188  }
5189
5190  return Type;
5191}
5192
5193/// GetBuiltinType - Return the type for the specified builtin.
5194QualType ASTContext::GetBuiltinType(unsigned id,
5195                                    GetBuiltinTypeError &Error) {
5196  const char *TypeStr = BuiltinInfo.GetTypeString(id);
5197
5198  llvm::SmallVector<QualType, 8> ArgTypes;
5199
5200  Error = GE_None;
5201  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error);
5202  if (Error != GE_None)
5203    return QualType();
5204  while (TypeStr[0] && TypeStr[0] != '.') {
5205    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error);
5206    if (Error != GE_None)
5207      return QualType();
5208
5209    // Do array -> pointer decay.  The builtin should use the decayed type.
5210    if (Ty->isArrayType())
5211      Ty = getArrayDecayedType(Ty);
5212
5213    ArgTypes.push_back(Ty);
5214  }
5215
5216  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
5217         "'.' should only occur at end of builtin type list!");
5218
5219  // handle untyped/variadic arguments "T c99Style();" or "T cppStyle(...);".
5220  if (ArgTypes.size() == 0 && TypeStr[0] == '.')
5221    return getFunctionNoProtoType(ResType);
5222
5223  // FIXME: Should we create noreturn types?
5224  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(),
5225                         TypeStr[0] == '.', 0, false, false, 0, 0,
5226                         FunctionType::ExtInfo());
5227}
5228
5229QualType
5230ASTContext::UsualArithmeticConversionsType(QualType lhs, QualType rhs) {
5231  // Perform the usual unary conversions. We do this early so that
5232  // integral promotions to "int" can allow us to exit early, in the
5233  // lhs == rhs check. Also, for conversion purposes, we ignore any
5234  // qualifiers.  For example, "const float" and "float" are
5235  // equivalent.
5236  if (lhs->isPromotableIntegerType())
5237    lhs = getPromotedIntegerType(lhs);
5238  else
5239    lhs = lhs.getUnqualifiedType();
5240  if (rhs->isPromotableIntegerType())
5241    rhs = getPromotedIntegerType(rhs);
5242  else
5243    rhs = rhs.getUnqualifiedType();
5244
5245  // If both types are identical, no conversion is needed.
5246  if (lhs == rhs)
5247    return lhs;
5248
5249  // If either side is a non-arithmetic type (e.g. a pointer), we are done.
5250  // The caller can deal with this (e.g. pointer + int).
5251  if (!lhs->isArithmeticType() || !rhs->isArithmeticType())
5252    return lhs;
5253
5254  // At this point, we have two different arithmetic types.
5255
5256  // Handle complex types first (C99 6.3.1.8p1).
5257  if (lhs->isComplexType() || rhs->isComplexType()) {
5258    // if we have an integer operand, the result is the complex type.
5259    if (rhs->isIntegerType() || rhs->isComplexIntegerType()) {
5260      // convert the rhs to the lhs complex type.
5261      return lhs;
5262    }
5263    if (lhs->isIntegerType() || lhs->isComplexIntegerType()) {
5264      // convert the lhs to the rhs complex type.
5265      return rhs;
5266    }
5267    // This handles complex/complex, complex/float, or float/complex.
5268    // When both operands are complex, the shorter operand is converted to the
5269    // type of the longer, and that is the type of the result. This corresponds
5270    // to what is done when combining two real floating-point operands.
5271    // The fun begins when size promotion occur across type domains.
5272    // From H&S 6.3.4: When one operand is complex and the other is a real
5273    // floating-point type, the less precise type is converted, within it's
5274    // real or complex domain, to the precision of the other type. For example,
5275    // when combining a "long double" with a "double _Complex", the
5276    // "double _Complex" is promoted to "long double _Complex".
5277    int result = getFloatingTypeOrder(lhs, rhs);
5278
5279    if (result > 0) { // The left side is bigger, convert rhs.
5280      rhs = getFloatingTypeOfSizeWithinDomain(lhs, rhs);
5281    } else if (result < 0) { // The right side is bigger, convert lhs.
5282      lhs = getFloatingTypeOfSizeWithinDomain(rhs, lhs);
5283    }
5284    // At this point, lhs and rhs have the same rank/size. Now, make sure the
5285    // domains match. This is a requirement for our implementation, C99
5286    // does not require this promotion.
5287    if (lhs != rhs) { // Domains don't match, we have complex/float mix.
5288      if (lhs->isRealFloatingType()) { // handle "double, _Complex double".
5289        return rhs;
5290      } else { // handle "_Complex double, double".
5291        return lhs;
5292      }
5293    }
5294    return lhs; // The domain/size match exactly.
5295  }
5296  // Now handle "real" floating types (i.e. float, double, long double).
5297  if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) {
5298    // if we have an integer operand, the result is the real floating type.
5299    if (rhs->isIntegerType()) {
5300      // convert rhs to the lhs floating point type.
5301      return lhs;
5302    }
5303    if (rhs->isComplexIntegerType()) {
5304      // convert rhs to the complex floating point type.
5305      return getComplexType(lhs);
5306    }
5307    if (lhs->isIntegerType()) {
5308      // convert lhs to the rhs floating point type.
5309      return rhs;
5310    }
5311    if (lhs->isComplexIntegerType()) {
5312      // convert lhs to the complex floating point type.
5313      return getComplexType(rhs);
5314    }
5315    // We have two real floating types, float/complex combos were handled above.
5316    // Convert the smaller operand to the bigger result.
5317    int result = getFloatingTypeOrder(lhs, rhs);
5318    if (result > 0) // convert the rhs
5319      return lhs;
5320    assert(result < 0 && "illegal float comparison");
5321    return rhs;   // convert the lhs
5322  }
5323  if (lhs->isComplexIntegerType() || rhs->isComplexIntegerType()) {
5324    // Handle GCC complex int extension.
5325    const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType();
5326    const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType();
5327
5328    if (lhsComplexInt && rhsComplexInt) {
5329      if (getIntegerTypeOrder(lhsComplexInt->getElementType(),
5330                              rhsComplexInt->getElementType()) >= 0)
5331        return lhs; // convert the rhs
5332      return rhs;
5333    } else if (lhsComplexInt && rhs->isIntegerType()) {
5334      // convert the rhs to the lhs complex type.
5335      return lhs;
5336    } else if (rhsComplexInt && lhs->isIntegerType()) {
5337      // convert the lhs to the rhs complex type.
5338      return rhs;
5339    }
5340  }
5341  // Finally, we have two differing integer types.
5342  // The rules for this case are in C99 6.3.1.8
5343  int compare = getIntegerTypeOrder(lhs, rhs);
5344  bool lhsSigned = lhs->isSignedIntegerType(),
5345       rhsSigned = rhs->isSignedIntegerType();
5346  QualType destType;
5347  if (lhsSigned == rhsSigned) {
5348    // Same signedness; use the higher-ranked type
5349    destType = compare >= 0 ? lhs : rhs;
5350  } else if (compare != (lhsSigned ? 1 : -1)) {
5351    // The unsigned type has greater than or equal rank to the
5352    // signed type, so use the unsigned type
5353    destType = lhsSigned ? rhs : lhs;
5354  } else if (getIntWidth(lhs) != getIntWidth(rhs)) {
5355    // The two types are different widths; if we are here, that
5356    // means the signed type is larger than the unsigned type, so
5357    // use the signed type.
5358    destType = lhsSigned ? lhs : rhs;
5359  } else {
5360    // The signed type is higher-ranked than the unsigned type,
5361    // but isn't actually any bigger (like unsigned int and long
5362    // on most 32-bit systems).  Use the unsigned type corresponding
5363    // to the signed type.
5364    destType = getCorrespondingUnsignedType(lhsSigned ? lhs : rhs);
5365  }
5366  return destType;
5367}
5368