ASTContext.cpp revision 00ccbefcffeb88ea3e2e6323e594fa968753ad14 
1//===--- ASTContext.cpp - Context to hold long-lived AST nodes ------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements the ASTContext interface.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/AST/ASTContext.h"
15#include "clang/AST/CharUnits.h"
16#include "clang/AST/DeclCXX.h"
17#include "clang/AST/DeclObjC.h"
18#include "clang/AST/DeclTemplate.h"
19#include "clang/AST/TypeLoc.h"
20#include "clang/AST/Expr.h"
21#include "clang/AST/ExprCXX.h"
22#include "clang/AST/ExternalASTSource.h"
23#include "clang/AST/ASTMutationListener.h"
24#include "clang/AST/RecordLayout.h"
25#include "clang/Basic/Builtins.h"
26#include "clang/Basic/SourceManager.h"
27#include "clang/Basic/TargetInfo.h"
28#include "llvm/ADT/SmallString.h"
29#include "llvm/ADT/StringExtras.h"
30#include "llvm/Support/MathExtras.h"
31#include "llvm/Support/raw_ostream.h"
32#include "CXXABI.h"
33
34using namespace clang;
35
36unsigned ASTContext::NumImplicitDefaultConstructors;
37unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
38unsigned ASTContext::NumImplicitCopyConstructors;
39unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
40unsigned ASTContext::NumImplicitCopyAssignmentOperators;
41unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
42unsigned ASTContext::NumImplicitDestructors;
43unsigned ASTContext::NumImplicitDestructorsDeclared;
44
45enum FloatingRank {
46  FloatRank, DoubleRank, LongDoubleRank
47};
48
49void
50ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
51                                               TemplateTemplateParmDecl *Parm) {
52  ID.AddInteger(Parm->getDepth());
53  ID.AddInteger(Parm->getPosition());
54  // FIXME: Parameter pack
55
56  TemplateParameterList *Params = Parm->getTemplateParameters();
57  ID.AddInteger(Params->size());
58  for (TemplateParameterList::const_iterator P = Params->begin(),
59                                          PEnd = Params->end();
60       P != PEnd; ++P) {
61    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
62      ID.AddInteger(0);
63      ID.AddBoolean(TTP->isParameterPack());
64      continue;
65    }
66
67    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
68      ID.AddInteger(1);
69      // FIXME: Parameter pack
70      ID.AddPointer(NTTP->getType().getAsOpaquePtr());
71      continue;
72    }
73
74    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
75    ID.AddInteger(2);
76    Profile(ID, TTP);
77  }
78}
79
80TemplateTemplateParmDecl *
81ASTContext::getCanonicalTemplateTemplateParmDecl(
82                                                 TemplateTemplateParmDecl *TTP) {
83  // Check if we already have a canonical template template parameter.
84  llvm::FoldingSetNodeID ID;
85  CanonicalTemplateTemplateParm::Profile(ID, TTP);
86  void *InsertPos = 0;
87  CanonicalTemplateTemplateParm *Canonical
88    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
89  if (Canonical)
90    return Canonical->getParam();
91
92  // Build a canonical template parameter list.
93  TemplateParameterList *Params = TTP->getTemplateParameters();
94  llvm::SmallVector<NamedDecl *, 4> CanonParams;
95  CanonParams.reserve(Params->size());
96  for (TemplateParameterList::const_iterator P = Params->begin(),
97                                          PEnd = Params->end();
98       P != PEnd; ++P) {
99    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
100      CanonParams.push_back(
101                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
102                                               SourceLocation(), TTP->getDepth(),
103                                               TTP->getIndex(), 0, false,
104                                               TTP->isParameterPack()));
105    else if (NonTypeTemplateParmDecl *NTTP
106             = dyn_cast<NonTypeTemplateParmDecl>(*P))
107      CanonParams.push_back(
108            NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
109                                            SourceLocation(), NTTP->getDepth(),
110                                            NTTP->getPosition(), 0,
111                                            getCanonicalType(NTTP->getType()),
112                                            0));
113    else
114      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
115                                           cast<TemplateTemplateParmDecl>(*P)));
116  }
117
118  TemplateTemplateParmDecl *CanonTTP
119    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
120                                       SourceLocation(), TTP->getDepth(),
121                                       TTP->getPosition(), 0,
122                         TemplateParameterList::Create(*this, SourceLocation(),
123                                                       SourceLocation(),
124                                                       CanonParams.data(),
125                                                       CanonParams.size(),
126                                                       SourceLocation()));
127
128  // Get the new insert position for the node we care about.
129  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
130  assert(Canonical == 0 && "Shouldn't be in the map!");
131  (void)Canonical;
132
133  // Create the canonical template template parameter entry.
134  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
135  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
136  return CanonTTP;
137}
138
139CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
140  if (!LangOpts.CPlusPlus) return 0;
141
142  switch (T.getCXXABI()) {
143  case CXXABI_ARM:
144    return CreateARMCXXABI(*this);
145  case CXXABI_Itanium:
146    return CreateItaniumCXXABI(*this);
147  case CXXABI_Microsoft:
148    return CreateMicrosoftCXXABI(*this);
149  }
150  return 0;
151}
152
153ASTContext::ASTContext(const LangOptions& LOpts, SourceManager &SM,
154                       const TargetInfo &t,
155                       IdentifierTable &idents, SelectorTable &sels,
156                       Builtin::Context &builtins,
157                       unsigned size_reserve) :
158  TemplateSpecializationTypes(this_()),
159  DependentTemplateSpecializationTypes(this_()),
160  GlobalNestedNameSpecifier(0), IsInt128Installed(false),
161  CFConstantStringTypeDecl(0), NSConstantStringTypeDecl(0),
162  ObjCFastEnumerationStateTypeDecl(0), FILEDecl(0), jmp_bufDecl(0),
163  sigjmp_bufDecl(0), BlockDescriptorType(0), BlockDescriptorExtendedType(0),
164  NullTypeSourceInfo(QualType()),
165  SourceMgr(SM), LangOpts(LOpts), ABI(createCXXABI(t)), Target(t),
166  Idents(idents), Selectors(sels),
167  BuiltinInfo(builtins),
168  DeclarationNames(*this),
169  ExternalSource(0), Listener(0), PrintingPolicy(LOpts),
170  LastSDM(0, 0),
171  UniqueBlockByRefTypeID(0), UniqueBlockParmTypeID(0) {
172  ObjCIdRedefinitionType = QualType();
173  ObjCClassRedefinitionType = QualType();
174  ObjCSelRedefinitionType = QualType();
175  if (size_reserve > 0) Types.reserve(size_reserve);
176  TUDecl = TranslationUnitDecl::Create(*this);
177  InitBuiltinTypes();
178}
179
180ASTContext::~ASTContext() {
181  // Release the DenseMaps associated with DeclContext objects.
182  // FIXME: Is this the ideal solution?
183  ReleaseDeclContextMaps();
184
185  // Call all of the deallocation functions.
186  for (unsigned I = 0, N = Deallocations.size(); I != N; ++I)
187    Deallocations[I].first(Deallocations[I].second);
188
189  // Release all of the memory associated with overridden C++ methods.
190  for (llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::iterator
191         OM = OverriddenMethods.begin(), OMEnd = OverriddenMethods.end();
192       OM != OMEnd; ++OM)
193    OM->second.Destroy();
194
195  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
196  // because they can contain DenseMaps.
197  for (llvm::DenseMap<const ObjCContainerDecl*,
198       const ASTRecordLayout*>::iterator
199       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
200    // Increment in loop to prevent using deallocated memory.
201    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
202      R->Destroy(*this);
203
204  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
205       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
206    // Increment in loop to prevent using deallocated memory.
207    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
208      R->Destroy(*this);
209  }
210
211  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
212                                                    AEnd = DeclAttrs.end();
213       A != AEnd; ++A)
214    A->second->~AttrVec();
215}
216
217void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
218  Deallocations.push_back(std::make_pair(Callback, Data));
219}
220
221void
222ASTContext::setExternalSource(llvm::OwningPtr<ExternalASTSource> &Source) {
223  ExternalSource.reset(Source.take());
224}
225
226void ASTContext::PrintStats() const {
227  fprintf(stderr, "*** AST Context Stats:\n");
228  fprintf(stderr, "  %d types total.\n", (int)Types.size());
229
230  unsigned counts[] = {
231#define TYPE(Name, Parent) 0,
232#define ABSTRACT_TYPE(Name, Parent)
233#include "clang/AST/TypeNodes.def"
234    0 // Extra
235  };
236
237  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
238    Type *T = Types[i];
239    counts[(unsigned)T->getTypeClass()]++;
240  }
241
242  unsigned Idx = 0;
243  unsigned TotalBytes = 0;
244#define TYPE(Name, Parent)                                              \
245  if (counts[Idx])                                                      \
246    fprintf(stderr, "    %d %s types\n", (int)counts[Idx], #Name);      \
247  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
248  ++Idx;
249#define ABSTRACT_TYPE(Name, Parent)
250#include "clang/AST/TypeNodes.def"
251
252  fprintf(stderr, "Total bytes = %d\n", int(TotalBytes));
253
254  // Implicit special member functions.
255  fprintf(stderr, "  %u/%u implicit default constructors created\n",
256          NumImplicitDefaultConstructorsDeclared,
257          NumImplicitDefaultConstructors);
258  fprintf(stderr, "  %u/%u implicit copy constructors created\n",
259          NumImplicitCopyConstructorsDeclared,
260          NumImplicitCopyConstructors);
261  fprintf(stderr, "  %u/%u implicit copy assignment operators created\n",
262          NumImplicitCopyAssignmentOperatorsDeclared,
263          NumImplicitCopyAssignmentOperators);
264  fprintf(stderr, "  %u/%u implicit destructors created\n",
265          NumImplicitDestructorsDeclared, NumImplicitDestructors);
266
267  if (ExternalSource.get()) {
268    fprintf(stderr, "\n");
269    ExternalSource->PrintStats();
270  }
271
272  BumpAlloc.PrintStats();
273}
274
275
276void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
277  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
278  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
279  Types.push_back(Ty);
280}
281
282void ASTContext::InitBuiltinTypes() {
283  assert(VoidTy.isNull() && "Context reinitialized?");
284
285  // C99 6.2.5p19.
286  InitBuiltinType(VoidTy,              BuiltinType::Void);
287
288  // C99 6.2.5p2.
289  InitBuiltinType(BoolTy,              BuiltinType::Bool);
290  // C99 6.2.5p3.
291  if (LangOpts.CharIsSigned)
292    InitBuiltinType(CharTy,            BuiltinType::Char_S);
293  else
294    InitBuiltinType(CharTy,            BuiltinType::Char_U);
295  // C99 6.2.5p4.
296  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
297  InitBuiltinType(ShortTy,             BuiltinType::Short);
298  InitBuiltinType(IntTy,               BuiltinType::Int);
299  InitBuiltinType(LongTy,              BuiltinType::Long);
300  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
301
302  // C99 6.2.5p6.
303  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
304  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
305  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
306  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
307  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
308
309  // C99 6.2.5p10.
310  InitBuiltinType(FloatTy,             BuiltinType::Float);
311  InitBuiltinType(DoubleTy,            BuiltinType::Double);
312  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
313
314  // GNU extension, 128-bit integers.
315  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
316  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
317
318  if (LangOpts.CPlusPlus) // C++ 3.9.1p5
319    InitBuiltinType(WCharTy,           BuiltinType::WChar);
320  else // C99
321    WCharTy = getFromTargetType(Target.getWCharType());
322
323  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
324    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
325  else // C99
326    Char16Ty = getFromTargetType(Target.getChar16Type());
327
328  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
329    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
330  else // C99
331    Char32Ty = getFromTargetType(Target.getChar32Type());
332
333  // Placeholder type for type-dependent expressions whose type is
334  // completely unknown. No code should ever check a type against
335  // DependentTy and users should never see it; however, it is here to
336  // help diagnose failures to properly check for type-dependent
337  // expressions.
338  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
339
340  // Placeholder type for functions.
341  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
342
343  // Placeholder type for C++0x auto declarations whose real type has
344  // not yet been deduced.
345  InitBuiltinType(UndeducedAutoTy,     BuiltinType::UndeducedAuto);
346
347  // C99 6.2.5p11.
348  FloatComplexTy      = getComplexType(FloatTy);
349  DoubleComplexTy     = getComplexType(DoubleTy);
350  LongDoubleComplexTy = getComplexType(LongDoubleTy);
351
352  BuiltinVaListType = QualType();
353
354  // "Builtin" typedefs set by Sema::ActOnTranslationUnitScope().
355  ObjCIdTypedefType = QualType();
356  ObjCClassTypedefType = QualType();
357  ObjCSelTypedefType = QualType();
358
359  // Builtin types for 'id', 'Class', and 'SEL'.
360  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
361  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
362  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
363
364  ObjCConstantStringType = QualType();
365
366  // void * type
367  VoidPtrTy = getPointerType(VoidTy);
368
369  // nullptr type (C++0x 2.14.7)
370  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
371}
372
373Diagnostic &ASTContext::getDiagnostics() const {
374  return SourceMgr.getDiagnostics();
375}
376
377AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
378  AttrVec *&Result = DeclAttrs[D];
379  if (!Result) {
380    void *Mem = Allocate(sizeof(AttrVec));
381    Result = new (Mem) AttrVec;
382  }
383
384  return *Result;
385}
386
387/// \brief Erase the attributes corresponding to the given declaration.
388void ASTContext::eraseDeclAttrs(const Decl *D) {
389  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
390  if (Pos != DeclAttrs.end()) {
391    Pos->second->~AttrVec();
392    DeclAttrs.erase(Pos);
393  }
394}
395
396
397MemberSpecializationInfo *
398ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
399  assert(Var->isStaticDataMember() && "Not a static data member");
400  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
401    = InstantiatedFromStaticDataMember.find(Var);
402  if (Pos == InstantiatedFromStaticDataMember.end())
403    return 0;
404
405  return Pos->second;
406}
407
408void
409ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
410                                                TemplateSpecializationKind TSK,
411                                          SourceLocation PointOfInstantiation) {
412  assert(Inst->isStaticDataMember() && "Not a static data member");
413  assert(Tmpl->isStaticDataMember() && "Not a static data member");
414  assert(!InstantiatedFromStaticDataMember[Inst] &&
415         "Already noted what static data member was instantiated from");
416  InstantiatedFromStaticDataMember[Inst]
417    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
418}
419
420NamedDecl *
421ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
422  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
423    = InstantiatedFromUsingDecl.find(UUD);
424  if (Pos == InstantiatedFromUsingDecl.end())
425    return 0;
426
427  return Pos->second;
428}
429
430void
431ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
432  assert((isa<UsingDecl>(Pattern) ||
433          isa<UnresolvedUsingValueDecl>(Pattern) ||
434          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
435         "pattern decl is not a using decl");
436  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
437  InstantiatedFromUsingDecl[Inst] = Pattern;
438}
439
440UsingShadowDecl *
441ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
442  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
443    = InstantiatedFromUsingShadowDecl.find(Inst);
444  if (Pos == InstantiatedFromUsingShadowDecl.end())
445    return 0;
446
447  return Pos->second;
448}
449
450void
451ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
452                                               UsingShadowDecl *Pattern) {
453  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
454  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
455}
456
457FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
458  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
459    = InstantiatedFromUnnamedFieldDecl.find(Field);
460  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
461    return 0;
462
463  return Pos->second;
464}
465
466void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
467                                                     FieldDecl *Tmpl) {
468  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
469  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
470  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
471         "Already noted what unnamed field was instantiated from");
472
473  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
474}
475
476ASTContext::overridden_cxx_method_iterator
477ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
478  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
479    = OverriddenMethods.find(Method);
480  if (Pos == OverriddenMethods.end())
481    return 0;
482
483  return Pos->second.begin();
484}
485
486ASTContext::overridden_cxx_method_iterator
487ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
488  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
489    = OverriddenMethods.find(Method);
490  if (Pos == OverriddenMethods.end())
491    return 0;
492
493  return Pos->second.end();
494}
495
496unsigned
497ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
498  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
499    = OverriddenMethods.find(Method);
500  if (Pos == OverriddenMethods.end())
501    return 0;
502
503  return Pos->second.size();
504}
505
506void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
507                                     const CXXMethodDecl *Overridden) {
508  OverriddenMethods[Method].push_back(Overridden);
509}
510
511//===----------------------------------------------------------------------===//
512//                         Type Sizing and Analysis
513//===----------------------------------------------------------------------===//
514
515/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
516/// scalar floating point type.
517const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
518  const BuiltinType *BT = T->getAs<BuiltinType>();
519  assert(BT && "Not a floating point type!");
520  switch (BT->getKind()) {
521  default: assert(0 && "Not a floating point type!");
522  case BuiltinType::Float:      return Target.getFloatFormat();
523  case BuiltinType::Double:     return Target.getDoubleFormat();
524  case BuiltinType::LongDouble: return Target.getLongDoubleFormat();
525  }
526}
527
528/// getDeclAlign - Return a conservative estimate of the alignment of the
529/// specified decl.  Note that bitfields do not have a valid alignment, so
530/// this method will assert on them.
531/// If @p RefAsPointee, references are treated like their underlying type
532/// (for alignof), else they're treated like pointers (for CodeGen).
533CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) {
534  unsigned Align = Target.getCharWidth();
535
536  bool UseAlignAttrOnly = false;
537  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
538    Align = AlignFromAttr;
539
540    // __attribute__((aligned)) can increase or decrease alignment
541    // *except* on a struct or struct member, where it only increases
542    // alignment unless 'packed' is also specified.
543    //
544    // It is an error for [[align]] to decrease alignment, so we can
545    // ignore that possibility;  Sema should diagnose it.
546    if (isa<FieldDecl>(D)) {
547      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
548        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
549    } else {
550      UseAlignAttrOnly = true;
551    }
552  }
553
554  if (UseAlignAttrOnly) {
555    // ignore type of value
556  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
557    QualType T = VD->getType();
558    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
559      if (RefAsPointee)
560        T = RT->getPointeeType();
561      else
562        T = getPointerType(RT->getPointeeType());
563    }
564    if (!T->isIncompleteType() && !T->isFunctionType()) {
565      unsigned MinWidth = Target.getLargeArrayMinWidth();
566      unsigned ArrayAlign = Target.getLargeArrayAlign();
567      if (isa<VariableArrayType>(T) && MinWidth != 0)
568        Align = std::max(Align, ArrayAlign);
569      if (ConstantArrayType *CT = dyn_cast<ConstantArrayType>(T)) {
570        unsigned Size = getTypeSize(CT);
571        if (MinWidth != 0 && MinWidth <= Size)
572          Align = std::max(Align, ArrayAlign);
573      }
574      // Incomplete or function types default to 1.
575      while (isa<VariableArrayType>(T) || isa<IncompleteArrayType>(T))
576        T = cast<ArrayType>(T)->getElementType();
577
578      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
579    }
580    if (const FieldDecl *FD = dyn_cast<FieldDecl>(VD)) {
581      // In the case of a field in a packed struct, we want the minimum
582      // of the alignment of the field and the alignment of the struct.
583      Align = std::min(Align,
584        getPreferredTypeAlign(FD->getParent()->getTypeForDecl()));
585    }
586  }
587
588  return CharUnits::fromQuantity(Align / Target.getCharWidth());
589}
590
591std::pair<CharUnits, CharUnits>
592ASTContext::getTypeInfoInChars(const Type *T) {
593  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
594  return std::make_pair(CharUnits::fromQuantity(Info.first / getCharWidth()),
595                        CharUnits::fromQuantity(Info.second / getCharWidth()));
596}
597
598std::pair<CharUnits, CharUnits>
599ASTContext::getTypeInfoInChars(QualType T) {
600  return getTypeInfoInChars(T.getTypePtr());
601}
602
603/// getTypeSize - Return the size of the specified type, in bits.  This method
604/// does not work on incomplete types.
605///
606/// FIXME: Pointers into different addr spaces could have different sizes and
607/// alignment requirements: getPointerInfo should take an AddrSpace, this
608/// should take a QualType, &c.
609std::pair<uint64_t, unsigned>
610ASTContext::getTypeInfo(const Type *T) {
611  uint64_t Width=0;
612  unsigned Align=8;
613  switch (T->getTypeClass()) {
614#define TYPE(Class, Base)
615#define ABSTRACT_TYPE(Class, Base)
616#define NON_CANONICAL_TYPE(Class, Base)
617#define DEPENDENT_TYPE(Class, Base) case Type::Class:
618#include "clang/AST/TypeNodes.def"
619    assert(false && "Should not see dependent types");
620    break;
621
622  case Type::FunctionNoProto:
623  case Type::FunctionProto:
624    // GCC extension: alignof(function) = 32 bits
625    Width = 0;
626    Align = 32;
627    break;
628
629  case Type::IncompleteArray:
630  case Type::VariableArray:
631    Width = 0;
632    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
633    break;
634
635  case Type::ConstantArray: {
636    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
637
638    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
639    Width = EltInfo.first*CAT->getSize().getZExtValue();
640    Align = EltInfo.second;
641    break;
642  }
643  case Type::ExtVector:
644  case Type::Vector: {
645    const VectorType *VT = cast<VectorType>(T);
646    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
647    Width = EltInfo.first*VT->getNumElements();
648    Align = Width;
649    // If the alignment is not a power of 2, round up to the next power of 2.
650    // This happens for non-power-of-2 length vectors.
651    if (Align & (Align-1)) {
652      Align = llvm::NextPowerOf2(Align);
653      Width = llvm::RoundUpToAlignment(Width, Align);
654    }
655    break;
656  }
657
658  case Type::Builtin:
659    switch (cast<BuiltinType>(T)->getKind()) {
660    default: assert(0 && "Unknown builtin type!");
661    case BuiltinType::Void:
662      // GCC extension: alignof(void) = 8 bits.
663      Width = 0;
664      Align = 8;
665      break;
666
667    case BuiltinType::Bool:
668      Width = Target.getBoolWidth();
669      Align = Target.getBoolAlign();
670      break;
671    case BuiltinType::Char_S:
672    case BuiltinType::Char_U:
673    case BuiltinType::UChar:
674    case BuiltinType::SChar:
675      Width = Target.getCharWidth();
676      Align = Target.getCharAlign();
677      break;
678    case BuiltinType::WChar:
679      Width = Target.getWCharWidth();
680      Align = Target.getWCharAlign();
681      break;
682    case BuiltinType::Char16:
683      Width = Target.getChar16Width();
684      Align = Target.getChar16Align();
685      break;
686    case BuiltinType::Char32:
687      Width = Target.getChar32Width();
688      Align = Target.getChar32Align();
689      break;
690    case BuiltinType::UShort:
691    case BuiltinType::Short:
692      Width = Target.getShortWidth();
693      Align = Target.getShortAlign();
694      break;
695    case BuiltinType::UInt:
696    case BuiltinType::Int:
697      Width = Target.getIntWidth();
698      Align = Target.getIntAlign();
699      break;
700    case BuiltinType::ULong:
701    case BuiltinType::Long:
702      Width = Target.getLongWidth();
703      Align = Target.getLongAlign();
704      break;
705    case BuiltinType::ULongLong:
706    case BuiltinType::LongLong:
707      Width = Target.getLongLongWidth();
708      Align = Target.getLongLongAlign();
709      break;
710    case BuiltinType::Int128:
711    case BuiltinType::UInt128:
712      Width = 128;
713      Align = 128; // int128_t is 128-bit aligned on all targets.
714      break;
715    case BuiltinType::Float:
716      Width = Target.getFloatWidth();
717      Align = Target.getFloatAlign();
718      break;
719    case BuiltinType::Double:
720      Width = Target.getDoubleWidth();
721      Align = Target.getDoubleAlign();
722      break;
723    case BuiltinType::LongDouble:
724      Width = Target.getLongDoubleWidth();
725      Align = Target.getLongDoubleAlign();
726      break;
727    case BuiltinType::NullPtr:
728      Width = Target.getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
729      Align = Target.getPointerAlign(0); //   == sizeof(void*)
730      break;
731    case BuiltinType::ObjCId:
732    case BuiltinType::ObjCClass:
733    case BuiltinType::ObjCSel:
734      Width = Target.getPointerWidth(0);
735      Align = Target.getPointerAlign(0);
736      break;
737    }
738    break;
739  case Type::ObjCObjectPointer:
740    Width = Target.getPointerWidth(0);
741    Align = Target.getPointerAlign(0);
742    break;
743  case Type::BlockPointer: {
744    unsigned AS = cast<BlockPointerType>(T)->getPointeeType().getAddressSpace();
745    Width = Target.getPointerWidth(AS);
746    Align = Target.getPointerAlign(AS);
747    break;
748  }
749  case Type::LValueReference:
750  case Type::RValueReference: {
751    // alignof and sizeof should never enter this code path here, so we go
752    // the pointer route.
753    unsigned AS = cast<ReferenceType>(T)->getPointeeType().getAddressSpace();
754    Width = Target.getPointerWidth(AS);
755    Align = Target.getPointerAlign(AS);
756    break;
757  }
758  case Type::Pointer: {
759    unsigned AS = cast<PointerType>(T)->getPointeeType().getAddressSpace();
760    Width = Target.getPointerWidth(AS);
761    Align = Target.getPointerAlign(AS);
762    break;
763  }
764  case Type::MemberPointer: {
765    const MemberPointerType *MPT = cast<MemberPointerType>(T);
766    std::pair<uint64_t, unsigned> PtrDiffInfo =
767      getTypeInfo(getPointerDiffType());
768    Width = PtrDiffInfo.first * ABI->getMemberPointerSize(MPT);
769    Align = PtrDiffInfo.second;
770    break;
771  }
772  case Type::Complex: {
773    // Complex types have the same alignment as their elements, but twice the
774    // size.
775    std::pair<uint64_t, unsigned> EltInfo =
776      getTypeInfo(cast<ComplexType>(T)->getElementType());
777    Width = EltInfo.first*2;
778    Align = EltInfo.second;
779    break;
780  }
781  case Type::ObjCObject:
782    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
783  case Type::ObjCInterface: {
784    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
785    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
786    Width = Layout.getSize();
787    Align = Layout.getAlignment();
788    break;
789  }
790  case Type::Record:
791  case Type::Enum: {
792    const TagType *TT = cast<TagType>(T);
793
794    if (TT->getDecl()->isInvalidDecl()) {
795      Width = 1;
796      Align = 1;
797      break;
798    }
799
800    if (const EnumType *ET = dyn_cast<EnumType>(TT))
801      return getTypeInfo(ET->getDecl()->getIntegerType());
802
803    const RecordType *RT = cast<RecordType>(TT);
804    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
805    Width = Layout.getSize();
806    Align = Layout.getAlignment();
807    break;
808  }
809
810  case Type::SubstTemplateTypeParm:
811    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
812                       getReplacementType().getTypePtr());
813
814  case Type::Paren:
815    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
816
817  case Type::Typedef: {
818    const TypedefDecl *Typedef = cast<TypedefType>(T)->getDecl();
819    std::pair<uint64_t, unsigned> Info
820      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
821    Align = std::max(Typedef->getMaxAlignment(), Info.second);
822    Width = Info.first;
823    break;
824  }
825
826  case Type::TypeOfExpr:
827    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
828                         .getTypePtr());
829
830  case Type::TypeOf:
831    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
832
833  case Type::Decltype:
834    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
835                        .getTypePtr());
836
837  case Type::Elaborated:
838    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
839
840  case Type::TemplateSpecialization:
841    assert(getCanonicalType(T) != T &&
842           "Cannot request the size of a dependent type");
843    // FIXME: this is likely to be wrong once we support template
844    // aliases, since a template alias could refer to a typedef that
845    // has an __aligned__ attribute on it.
846    return getTypeInfo(getCanonicalType(T));
847  }
848
849  assert(Align && (Align & (Align-1)) == 0 && "Alignment must be power of 2");
850  return std::make_pair(Width, Align);
851}
852
853/// getTypeSizeInChars - Return the size of the specified type, in characters.
854/// This method does not work on incomplete types.
855CharUnits ASTContext::getTypeSizeInChars(QualType T) {
856  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
857}
858CharUnits ASTContext::getTypeSizeInChars(const Type *T) {
859  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
860}
861
862/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
863/// characters. This method does not work on incomplete types.
864CharUnits ASTContext::getTypeAlignInChars(QualType T) {
865  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
866}
867CharUnits ASTContext::getTypeAlignInChars(const Type *T) {
868  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
869}
870
871/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
872/// type for the current target in bits.  This can be different than the ABI
873/// alignment in cases where it is beneficial for performance to overalign
874/// a data type.
875unsigned ASTContext::getPreferredTypeAlign(const Type *T) {
876  unsigned ABIAlign = getTypeAlign(T);
877
878  // Double and long long should be naturally aligned if possible.
879  if (const ComplexType* CT = T->getAs<ComplexType>())
880    T = CT->getElementType().getTypePtr();
881  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
882      T->isSpecificBuiltinType(BuiltinType::LongLong))
883    return std::max(ABIAlign, (unsigned)getTypeSize(T));
884
885  return ABIAlign;
886}
887
888/// ShallowCollectObjCIvars -
889/// Collect all ivars, including those synthesized, in the current class.
890///
891void ASTContext::ShallowCollectObjCIvars(const ObjCInterfaceDecl *OI,
892                                 llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
893  // FIXME. This need be removed but there are two many places which
894  // assume const-ness of ObjCInterfaceDecl
895  ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
896  for (ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
897        Iv= Iv->getNextIvar())
898    Ivars.push_back(Iv);
899}
900
901/// DeepCollectObjCIvars -
902/// This routine first collects all declared, but not synthesized, ivars in
903/// super class and then collects all ivars, including those synthesized for
904/// current class. This routine is used for implementation of current class
905/// when all ivars, declared and synthesized are known.
906///
907void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
908                                      bool leafClass,
909                                llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
910  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
911    DeepCollectObjCIvars(SuperClass, false, Ivars);
912  if (!leafClass) {
913    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
914         E = OI->ivar_end(); I != E; ++I)
915      Ivars.push_back(*I);
916  }
917  else
918    ShallowCollectObjCIvars(OI, Ivars);
919}
920
921/// CollectInheritedProtocols - Collect all protocols in current class and
922/// those inherited by it.
923void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
924                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
925  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
926    // We can use protocol_iterator here instead of
927    // all_referenced_protocol_iterator since we are walking all categories.
928    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
929         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
930      ObjCProtocolDecl *Proto = (*P);
931      Protocols.insert(Proto);
932      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
933           PE = Proto->protocol_end(); P != PE; ++P) {
934        Protocols.insert(*P);
935        CollectInheritedProtocols(*P, Protocols);
936      }
937    }
938
939    // Categories of this Interface.
940    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
941         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
942      CollectInheritedProtocols(CDeclChain, Protocols);
943    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
944      while (SD) {
945        CollectInheritedProtocols(SD, Protocols);
946        SD = SD->getSuperClass();
947      }
948  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
949    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
950         PE = OC->protocol_end(); P != PE; ++P) {
951      ObjCProtocolDecl *Proto = (*P);
952      Protocols.insert(Proto);
953      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
954           PE = Proto->protocol_end(); P != PE; ++P)
955        CollectInheritedProtocols(*P, Protocols);
956    }
957  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
958    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
959         PE = OP->protocol_end(); P != PE; ++P) {
960      ObjCProtocolDecl *Proto = (*P);
961      Protocols.insert(Proto);
962      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
963           PE = Proto->protocol_end(); P != PE; ++P)
964        CollectInheritedProtocols(*P, Protocols);
965    }
966  }
967}
968
969unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) {
970  unsigned count = 0;
971  // Count ivars declared in class extension.
972  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
973       CDecl = CDecl->getNextClassExtension())
974    count += CDecl->ivar_size();
975
976  // Count ivar defined in this class's implementation.  This
977  // includes synthesized ivars.
978  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
979    count += ImplDecl->ivar_size();
980
981  return count;
982}
983
984/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
985ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
986  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
987    I = ObjCImpls.find(D);
988  if (I != ObjCImpls.end())
989    return cast<ObjCImplementationDecl>(I->second);
990  return 0;
991}
992/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
993ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
994  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
995    I = ObjCImpls.find(D);
996  if (I != ObjCImpls.end())
997    return cast<ObjCCategoryImplDecl>(I->second);
998  return 0;
999}
1000
1001/// \brief Set the implementation of ObjCInterfaceDecl.
1002void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1003                           ObjCImplementationDecl *ImplD) {
1004  assert(IFaceD && ImplD && "Passed null params");
1005  ObjCImpls[IFaceD] = ImplD;
1006}
1007/// \brief Set the implementation of ObjCCategoryDecl.
1008void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1009                           ObjCCategoryImplDecl *ImplD) {
1010  assert(CatD && ImplD && "Passed null params");
1011  ObjCImpls[CatD] = ImplD;
1012}
1013
1014/// \brief Get the copy initialization expression of VarDecl,or NULL if
1015/// none exists.
1016Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
1017  assert(VD && "Passed null params");
1018  assert(VD->hasAttr<BlocksAttr>() &&
1019         "getBlockVarCopyInits - not __block var");
1020  llvm::DenseMap<const VarDecl*, Expr*>::iterator
1021    I = BlockVarCopyInits.find(VD);
1022  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : 0;
1023}
1024
1025/// \brief Set the copy inialization expression of a block var decl.
1026void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
1027  assert(VD && Init && "Passed null params");
1028  assert(VD->hasAttr<BlocksAttr>() &&
1029         "setBlockVarCopyInits - not __block var");
1030  BlockVarCopyInits[VD] = Init;
1031}
1032
1033/// \brief Allocate an uninitialized TypeSourceInfo.
1034///
1035/// The caller should initialize the memory held by TypeSourceInfo using
1036/// the TypeLoc wrappers.
1037///
1038/// \param T the type that will be the basis for type source info. This type
1039/// should refer to how the declarator was written in source code, not to
1040/// what type semantic analysis resolved the declarator to.
1041TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1042                                                 unsigned DataSize) {
1043  if (!DataSize)
1044    DataSize = TypeLoc::getFullDataSizeForType(T);
1045  else
1046    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1047           "incorrect data size provided to CreateTypeSourceInfo!");
1048
1049  TypeSourceInfo *TInfo =
1050    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1051  new (TInfo) TypeSourceInfo(T);
1052  return TInfo;
1053}
1054
1055TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1056                                                     SourceLocation L) {
1057  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1058  DI->getTypeLoc().initialize(L);
1059  return DI;
1060}
1061
1062const ASTRecordLayout &
1063ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) {
1064  return getObjCLayout(D, 0);
1065}
1066
1067const ASTRecordLayout &
1068ASTContext::getASTObjCImplementationLayout(const ObjCImplementationDecl *D) {
1069  return getObjCLayout(D->getClassInterface(), D);
1070}
1071
1072//===----------------------------------------------------------------------===//
1073//                   Type creation/memoization methods
1074//===----------------------------------------------------------------------===//
1075
1076QualType ASTContext::getExtQualType(const Type *TypeNode, Qualifiers Quals) {
1077  unsigned Fast = Quals.getFastQualifiers();
1078  Quals.removeFastQualifiers();
1079
1080  // Check if we've already instantiated this type.
1081  llvm::FoldingSetNodeID ID;
1082  ExtQuals::Profile(ID, TypeNode, Quals);
1083  void *InsertPos = 0;
1084  if (ExtQuals *EQ = ExtQualNodes.FindNodeOrInsertPos(ID, InsertPos)) {
1085    assert(EQ->getQualifiers() == Quals);
1086    QualType T = QualType(EQ, Fast);
1087    return T;
1088  }
1089
1090  ExtQuals *New = new (*this, TypeAlignment) ExtQuals(TypeNode, Quals);
1091  ExtQualNodes.InsertNode(New, InsertPos);
1092  QualType T = QualType(New, Fast);
1093  return T;
1094}
1095
1096QualType ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) {
1097  QualType CanT = getCanonicalType(T);
1098  if (CanT.getAddressSpace() == AddressSpace)
1099    return T;
1100
1101  // If we are composing extended qualifiers together, merge together
1102  // into one ExtQuals node.
1103  QualifierCollector Quals;
1104  const Type *TypeNode = Quals.strip(T);
1105
1106  // If this type already has an address space specified, it cannot get
1107  // another one.
1108  assert(!Quals.hasAddressSpace() &&
1109         "Type cannot be in multiple addr spaces!");
1110  Quals.addAddressSpace(AddressSpace);
1111
1112  return getExtQualType(TypeNode, Quals);
1113}
1114
1115QualType ASTContext::getObjCGCQualType(QualType T,
1116                                       Qualifiers::GC GCAttr) {
1117  QualType CanT = getCanonicalType(T);
1118  if (CanT.getObjCGCAttr() == GCAttr)
1119    return T;
1120
1121  if (T->isPointerType()) {
1122    QualType Pointee = T->getAs<PointerType>()->getPointeeType();
1123    if (Pointee->isAnyPointerType()) {
1124      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1125      return getPointerType(ResultType);
1126    }
1127  }
1128
1129  // If we are composing extended qualifiers together, merge together
1130  // into one ExtQuals node.
1131  QualifierCollector Quals;
1132  const Type *TypeNode = Quals.strip(T);
1133
1134  // If this type already has an ObjCGC specified, it cannot get
1135  // another one.
1136  assert(!Quals.hasObjCGCAttr() &&
1137         "Type cannot have multiple ObjCGCs!");
1138  Quals.addObjCGCAttr(GCAttr);
1139
1140  return getExtQualType(TypeNode, Quals);
1141}
1142
1143const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
1144                                                   FunctionType::ExtInfo Info) {
1145  if (T->getExtInfo() == Info)
1146    return T;
1147
1148  QualType Result;
1149  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
1150    Result = getFunctionNoProtoType(FNPT->getResultType(), Info);
1151  } else {
1152    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
1153    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
1154    EPI.ExtInfo = Info;
1155    Result = getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1156                             FPT->getNumArgs(), EPI);
1157  }
1158
1159  return cast<FunctionType>(Result.getTypePtr());
1160}
1161
1162/// getComplexType - Return the uniqued reference to the type for a complex
1163/// number with the specified element type.
1164QualType ASTContext::getComplexType(QualType T) {
1165  // Unique pointers, to guarantee there is only one pointer of a particular
1166  // structure.
1167  llvm::FoldingSetNodeID ID;
1168  ComplexType::Profile(ID, T);
1169
1170  void *InsertPos = 0;
1171  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1172    return QualType(CT, 0);
1173
1174  // If the pointee type isn't canonical, this won't be a canonical type either,
1175  // so fill in the canonical type field.
1176  QualType Canonical;
1177  if (!T.isCanonical()) {
1178    Canonical = getComplexType(getCanonicalType(T));
1179
1180    // Get the new insert position for the node we care about.
1181    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1182    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1183  }
1184  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1185  Types.push_back(New);
1186  ComplexTypes.InsertNode(New, InsertPos);
1187  return QualType(New, 0);
1188}
1189
1190/// getPointerType - Return the uniqued reference to the type for a pointer to
1191/// the specified type.
1192QualType ASTContext::getPointerType(QualType T) {
1193  // Unique pointers, to guarantee there is only one pointer of a particular
1194  // structure.
1195  llvm::FoldingSetNodeID ID;
1196  PointerType::Profile(ID, T);
1197
1198  void *InsertPos = 0;
1199  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1200    return QualType(PT, 0);
1201
1202  // If the pointee type isn't canonical, this won't be a canonical type either,
1203  // so fill in the canonical type field.
1204  QualType Canonical;
1205  if (!T.isCanonical()) {
1206    Canonical = getPointerType(getCanonicalType(T));
1207
1208    // Get the new insert position for the node we care about.
1209    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1210    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1211  }
1212  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1213  Types.push_back(New);
1214  PointerTypes.InsertNode(New, InsertPos);
1215  return QualType(New, 0);
1216}
1217
1218/// getBlockPointerType - Return the uniqued reference to the type for
1219/// a pointer to the specified block.
1220QualType ASTContext::getBlockPointerType(QualType T) {
1221  assert(T->isFunctionType() && "block of function types only");
1222  // Unique pointers, to guarantee there is only one block of a particular
1223  // structure.
1224  llvm::FoldingSetNodeID ID;
1225  BlockPointerType::Profile(ID, T);
1226
1227  void *InsertPos = 0;
1228  if (BlockPointerType *PT =
1229        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1230    return QualType(PT, 0);
1231
1232  // If the block pointee type isn't canonical, this won't be a canonical
1233  // type either so fill in the canonical type field.
1234  QualType Canonical;
1235  if (!T.isCanonical()) {
1236    Canonical = getBlockPointerType(getCanonicalType(T));
1237
1238    // Get the new insert position for the node we care about.
1239    BlockPointerType *NewIP =
1240      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1241    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1242  }
1243  BlockPointerType *New
1244    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1245  Types.push_back(New);
1246  BlockPointerTypes.InsertNode(New, InsertPos);
1247  return QualType(New, 0);
1248}
1249
1250/// getLValueReferenceType - Return the uniqued reference to the type for an
1251/// lvalue reference to the specified type.
1252QualType ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) {
1253  // Unique pointers, to guarantee there is only one pointer of a particular
1254  // structure.
1255  llvm::FoldingSetNodeID ID;
1256  ReferenceType::Profile(ID, T, SpelledAsLValue);
1257
1258  void *InsertPos = 0;
1259  if (LValueReferenceType *RT =
1260        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1261    return QualType(RT, 0);
1262
1263  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1264
1265  // If the referencee type isn't canonical, this won't be a canonical type
1266  // either, so fill in the canonical type field.
1267  QualType Canonical;
1268  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1269    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1270    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1271
1272    // Get the new insert position for the node we care about.
1273    LValueReferenceType *NewIP =
1274      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1275    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1276  }
1277
1278  LValueReferenceType *New
1279    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1280                                                     SpelledAsLValue);
1281  Types.push_back(New);
1282  LValueReferenceTypes.InsertNode(New, InsertPos);
1283
1284  return QualType(New, 0);
1285}
1286
1287/// getRValueReferenceType - Return the uniqued reference to the type for an
1288/// rvalue reference to the specified type.
1289QualType ASTContext::getRValueReferenceType(QualType T) {
1290  // Unique pointers, to guarantee there is only one pointer of a particular
1291  // structure.
1292  llvm::FoldingSetNodeID ID;
1293  ReferenceType::Profile(ID, T, false);
1294
1295  void *InsertPos = 0;
1296  if (RValueReferenceType *RT =
1297        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1298    return QualType(RT, 0);
1299
1300  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1301
1302  // If the referencee type isn't canonical, this won't be a canonical type
1303  // either, so fill in the canonical type field.
1304  QualType Canonical;
1305  if (InnerRef || !T.isCanonical()) {
1306    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1307    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1308
1309    // Get the new insert position for the node we care about.
1310    RValueReferenceType *NewIP =
1311      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1312    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1313  }
1314
1315  RValueReferenceType *New
1316    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1317  Types.push_back(New);
1318  RValueReferenceTypes.InsertNode(New, InsertPos);
1319  return QualType(New, 0);
1320}
1321
1322/// getMemberPointerType - Return the uniqued reference to the type for a
1323/// member pointer to the specified type, in the specified class.
1324QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) {
1325  // Unique pointers, to guarantee there is only one pointer of a particular
1326  // structure.
1327  llvm::FoldingSetNodeID ID;
1328  MemberPointerType::Profile(ID, T, Cls);
1329
1330  void *InsertPos = 0;
1331  if (MemberPointerType *PT =
1332      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1333    return QualType(PT, 0);
1334
1335  // If the pointee or class type isn't canonical, this won't be a canonical
1336  // type either, so fill in the canonical type field.
1337  QualType Canonical;
1338  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1339    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1340
1341    // Get the new insert position for the node we care about.
1342    MemberPointerType *NewIP =
1343      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1344    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1345  }
1346  MemberPointerType *New
1347    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1348  Types.push_back(New);
1349  MemberPointerTypes.InsertNode(New, InsertPos);
1350  return QualType(New, 0);
1351}
1352
1353/// getConstantArrayType - Return the unique reference to the type for an
1354/// array of the specified element type.
1355QualType ASTContext::getConstantArrayType(QualType EltTy,
1356                                          const llvm::APInt &ArySizeIn,
1357                                          ArrayType::ArraySizeModifier ASM,
1358                                          unsigned EltTypeQuals) {
1359  assert((EltTy->isDependentType() ||
1360          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1361         "Constant array of VLAs is illegal!");
1362
1363  // Convert the array size into a canonical width matching the pointer size for
1364  // the target.
1365  llvm::APInt ArySize(ArySizeIn);
1366  ArySize =
1367    ArySize.zextOrTrunc(Target.getPointerWidth(EltTy.getAddressSpace()));
1368
1369  llvm::FoldingSetNodeID ID;
1370  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, EltTypeQuals);
1371
1372  void *InsertPos = 0;
1373  if (ConstantArrayType *ATP =
1374      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1375    return QualType(ATP, 0);
1376
1377  // If the element type isn't canonical, this won't be a canonical type either,
1378  // so fill in the canonical type field.
1379  QualType Canonical;
1380  if (!EltTy.isCanonical()) {
1381    Canonical = getConstantArrayType(getCanonicalType(EltTy), ArySize,
1382                                     ASM, EltTypeQuals);
1383    // Get the new insert position for the node we care about.
1384    ConstantArrayType *NewIP =
1385      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1386    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1387  }
1388
1389  ConstantArrayType *New = new(*this,TypeAlignment)
1390    ConstantArrayType(EltTy, Canonical, ArySize, ASM, EltTypeQuals);
1391  ConstantArrayTypes.InsertNode(New, InsertPos);
1392  Types.push_back(New);
1393  return QualType(New, 0);
1394}
1395
1396/// getIncompleteArrayType - Returns a unique reference to the type for a
1397/// incomplete array of the specified element type.
1398QualType ASTContext::getUnknownSizeVariableArrayType(QualType Ty) {
1399  QualType ElemTy = getBaseElementType(Ty);
1400  DeclarationName Name;
1401  llvm::SmallVector<QualType, 8> ATypes;
1402  QualType ATy = Ty;
1403  while (const ArrayType *AT = getAsArrayType(ATy)) {
1404    ATypes.push_back(ATy);
1405    ATy = AT->getElementType();
1406  }
1407  for (int i = ATypes.size() - 1; i >= 0; i--) {
1408    if (const VariableArrayType *VAT = getAsVariableArrayType(ATypes[i])) {
1409      ElemTy = getVariableArrayType(ElemTy, /*ArraySize*/0, ArrayType::Star,
1410                                    0, VAT->getBracketsRange());
1411    }
1412    else if (const ConstantArrayType *CAT = getAsConstantArrayType(ATypes[i])) {
1413      llvm::APSInt ConstVal(CAT->getSize());
1414      ElemTy = getConstantArrayType(ElemTy, ConstVal, ArrayType::Normal, 0);
1415    }
1416    else if (getAsIncompleteArrayType(ATypes[i])) {
1417      ElemTy = getVariableArrayType(ElemTy, /*ArraySize*/0, ArrayType::Normal,
1418                                    0, SourceRange());
1419    }
1420    else
1421      assert(false && "DependentArrayType is seen");
1422  }
1423  return ElemTy;
1424}
1425
1426/// getVariableArrayDecayedType - Returns a vla type where known sizes
1427/// are replaced with [*]
1428QualType ASTContext::getVariableArrayDecayedType(QualType Ty) {
1429  if (Ty->isPointerType()) {
1430    QualType BaseType = Ty->getAs<PointerType>()->getPointeeType();
1431    if (isa<VariableArrayType>(BaseType)) {
1432      ArrayType *AT = dyn_cast<ArrayType>(BaseType);
1433      VariableArrayType *VAT = cast<VariableArrayType>(AT);
1434      if (VAT->getSizeExpr()) {
1435        Ty = getUnknownSizeVariableArrayType(BaseType);
1436        Ty = getPointerType(Ty);
1437      }
1438    }
1439  }
1440  return Ty;
1441}
1442
1443
1444/// getVariableArrayType - Returns a non-unique reference to the type for a
1445/// variable array of the specified element type.
1446QualType ASTContext::getVariableArrayType(QualType EltTy,
1447                                          Expr *NumElts,
1448                                          ArrayType::ArraySizeModifier ASM,
1449                                          unsigned EltTypeQuals,
1450                                          SourceRange Brackets) {
1451  // Since we don't unique expressions, it isn't possible to unique VLA's
1452  // that have an expression provided for their size.
1453  QualType CanonType;
1454
1455  if (!EltTy.isCanonical()) {
1456    CanonType = getVariableArrayType(getCanonicalType(EltTy), NumElts, ASM,
1457                                     EltTypeQuals, Brackets);
1458  }
1459
1460  VariableArrayType *New = new(*this, TypeAlignment)
1461    VariableArrayType(EltTy, CanonType, NumElts, ASM, EltTypeQuals, Brackets);
1462
1463  VariableArrayTypes.push_back(New);
1464  Types.push_back(New);
1465  return QualType(New, 0);
1466}
1467
1468/// getDependentSizedArrayType - Returns a non-unique reference to
1469/// the type for a dependently-sized array of the specified element
1470/// type.
1471QualType ASTContext::getDependentSizedArrayType(QualType EltTy,
1472                                                Expr *NumElts,
1473                                                ArrayType::ArraySizeModifier ASM,
1474                                                unsigned EltTypeQuals,
1475                                                SourceRange Brackets) {
1476  assert((!NumElts || NumElts->isTypeDependent() ||
1477          NumElts->isValueDependent()) &&
1478         "Size must be type- or value-dependent!");
1479
1480  void *InsertPos = 0;
1481  DependentSizedArrayType *Canon = 0;
1482  llvm::FoldingSetNodeID ID;
1483
1484  QualType CanonicalEltTy = getCanonicalType(EltTy);
1485  if (NumElts) {
1486    // Dependently-sized array types that do not have a specified
1487    // number of elements will have their sizes deduced from an
1488    // initializer.
1489    DependentSizedArrayType::Profile(ID, *this, CanonicalEltTy, ASM,
1490                                     EltTypeQuals, NumElts);
1491
1492    Canon = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1493  }
1494
1495  DependentSizedArrayType *New;
1496  if (Canon) {
1497    // We already have a canonical version of this array type; use it as
1498    // the canonical type for a newly-built type.
1499    New = new (*this, TypeAlignment)
1500      DependentSizedArrayType(*this, EltTy, QualType(Canon, 0),
1501                              NumElts, ASM, EltTypeQuals, Brackets);
1502  } else if (CanonicalEltTy == EltTy) {
1503    // This is a canonical type. Record it.
1504    New = new (*this, TypeAlignment)
1505      DependentSizedArrayType(*this, EltTy, QualType(),
1506                              NumElts, ASM, EltTypeQuals, Brackets);
1507
1508    if (NumElts) {
1509#ifndef NDEBUG
1510      DependentSizedArrayType *CanonCheck
1511        = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1512      assert(!CanonCheck && "Dependent-sized canonical array type broken");
1513      (void)CanonCheck;
1514#endif
1515      DependentSizedArrayTypes.InsertNode(New, InsertPos);
1516    }
1517  } else {
1518    QualType Canon = getDependentSizedArrayType(CanonicalEltTy, NumElts,
1519                                                ASM, EltTypeQuals,
1520                                                SourceRange());
1521    New = new (*this, TypeAlignment)
1522      DependentSizedArrayType(*this, EltTy, Canon,
1523                              NumElts, ASM, EltTypeQuals, Brackets);
1524  }
1525
1526  Types.push_back(New);
1527  return QualType(New, 0);
1528}
1529
1530QualType ASTContext::getIncompleteArrayType(QualType EltTy,
1531                                            ArrayType::ArraySizeModifier ASM,
1532                                            unsigned EltTypeQuals) {
1533  llvm::FoldingSetNodeID ID;
1534  IncompleteArrayType::Profile(ID, EltTy, ASM, EltTypeQuals);
1535
1536  void *InsertPos = 0;
1537  if (IncompleteArrayType *ATP =
1538       IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1539    return QualType(ATP, 0);
1540
1541  // If the element type isn't canonical, this won't be a canonical type
1542  // either, so fill in the canonical type field.
1543  QualType Canonical;
1544
1545  if (!EltTy.isCanonical()) {
1546    Canonical = getIncompleteArrayType(getCanonicalType(EltTy),
1547                                       ASM, EltTypeQuals);
1548
1549    // Get the new insert position for the node we care about.
1550    IncompleteArrayType *NewIP =
1551      IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1552    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1553  }
1554
1555  IncompleteArrayType *New = new (*this, TypeAlignment)
1556    IncompleteArrayType(EltTy, Canonical, ASM, EltTypeQuals);
1557
1558  IncompleteArrayTypes.InsertNode(New, InsertPos);
1559  Types.push_back(New);
1560  return QualType(New, 0);
1561}
1562
1563/// getVectorType - Return the unique reference to a vector type of
1564/// the specified element type and size. VectorType must be a built-in type.
1565QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1566                                   VectorType::VectorKind VecKind) {
1567  BuiltinType *BaseType;
1568
1569  BaseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1570  assert(BaseType != 0 && "getVectorType(): Expecting a built-in type");
1571
1572  // Check if we've already instantiated a vector of this type.
1573  llvm::FoldingSetNodeID ID;
1574  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
1575
1576  void *InsertPos = 0;
1577  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1578    return QualType(VTP, 0);
1579
1580  // If the element type isn't canonical, this won't be a canonical type either,
1581  // so fill in the canonical type field.
1582  QualType Canonical;
1583  if (!vecType.isCanonical()) {
1584    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
1585
1586    // Get the new insert position for the node we care about.
1587    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1588    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1589  }
1590  VectorType *New = new (*this, TypeAlignment)
1591    VectorType(vecType, NumElts, Canonical, VecKind);
1592  VectorTypes.InsertNode(New, InsertPos);
1593  Types.push_back(New);
1594  return QualType(New, 0);
1595}
1596
1597/// getExtVectorType - Return the unique reference to an extended vector type of
1598/// the specified element type and size. VectorType must be a built-in type.
1599QualType ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) {
1600  BuiltinType *baseType;
1601
1602  baseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1603  assert(baseType != 0 && "getExtVectorType(): Expecting a built-in type");
1604
1605  // Check if we've already instantiated a vector of this type.
1606  llvm::FoldingSetNodeID ID;
1607  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1608                      VectorType::GenericVector);
1609  void *InsertPos = 0;
1610  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1611    return QualType(VTP, 0);
1612
1613  // If the element type isn't canonical, this won't be a canonical type either,
1614  // so fill in the canonical type field.
1615  QualType Canonical;
1616  if (!vecType.isCanonical()) {
1617    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
1618
1619    // Get the new insert position for the node we care about.
1620    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1621    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1622  }
1623  ExtVectorType *New = new (*this, TypeAlignment)
1624    ExtVectorType(vecType, NumElts, Canonical);
1625  VectorTypes.InsertNode(New, InsertPos);
1626  Types.push_back(New);
1627  return QualType(New, 0);
1628}
1629
1630QualType ASTContext::getDependentSizedExtVectorType(QualType vecType,
1631                                                    Expr *SizeExpr,
1632                                                    SourceLocation AttrLoc) {
1633  llvm::FoldingSetNodeID ID;
1634  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
1635                                       SizeExpr);
1636
1637  void *InsertPos = 0;
1638  DependentSizedExtVectorType *Canon
1639    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1640  DependentSizedExtVectorType *New;
1641  if (Canon) {
1642    // We already have a canonical version of this array type; use it as
1643    // the canonical type for a newly-built type.
1644    New = new (*this, TypeAlignment)
1645      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
1646                                  SizeExpr, AttrLoc);
1647  } else {
1648    QualType CanonVecTy = getCanonicalType(vecType);
1649    if (CanonVecTy == vecType) {
1650      New = new (*this, TypeAlignment)
1651        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
1652                                    AttrLoc);
1653
1654      DependentSizedExtVectorType *CanonCheck
1655        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1656      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
1657      (void)CanonCheck;
1658      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
1659    } else {
1660      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
1661                                                      SourceLocation());
1662      New = new (*this, TypeAlignment)
1663        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
1664    }
1665  }
1666
1667  Types.push_back(New);
1668  return QualType(New, 0);
1669}
1670
1671/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
1672///
1673QualType ASTContext::getFunctionNoProtoType(QualType ResultTy,
1674                                            const FunctionType::ExtInfo &Info) {
1675  const CallingConv CallConv = Info.getCC();
1676  // Unique functions, to guarantee there is only one function of a particular
1677  // structure.
1678  llvm::FoldingSetNodeID ID;
1679  FunctionNoProtoType::Profile(ID, ResultTy, Info);
1680
1681  void *InsertPos = 0;
1682  if (FunctionNoProtoType *FT =
1683        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1684    return QualType(FT, 0);
1685
1686  QualType Canonical;
1687  if (!ResultTy.isCanonical() ||
1688      getCanonicalCallConv(CallConv) != CallConv) {
1689    Canonical =
1690      getFunctionNoProtoType(getCanonicalType(ResultTy),
1691                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1692
1693    // Get the new insert position for the node we care about.
1694    FunctionNoProtoType *NewIP =
1695      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1696    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1697  }
1698
1699  FunctionNoProtoType *New = new (*this, TypeAlignment)
1700    FunctionNoProtoType(ResultTy, Canonical, Info);
1701  Types.push_back(New);
1702  FunctionNoProtoTypes.InsertNode(New, InsertPos);
1703  return QualType(New, 0);
1704}
1705
1706/// getFunctionType - Return a normal function type with a typed argument
1707/// list.  isVariadic indicates whether the argument list includes '...'.
1708QualType ASTContext::getFunctionType(QualType ResultTy,
1709                                     const QualType *ArgArray, unsigned NumArgs,
1710                                   const FunctionProtoType::ExtProtoInfo &EPI) {
1711  // Unique functions, to guarantee there is only one function of a particular
1712  // structure.
1713  llvm::FoldingSetNodeID ID;
1714  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, EPI);
1715
1716  void *InsertPos = 0;
1717  if (FunctionProtoType *FTP =
1718        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1719    return QualType(FTP, 0);
1720
1721  // Determine whether the type being created is already canonical or not.
1722  bool isCanonical = !EPI.HasExceptionSpec && ResultTy.isCanonical();
1723  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
1724    if (!ArgArray[i].isCanonicalAsParam())
1725      isCanonical = false;
1726
1727  const CallingConv CallConv = EPI.ExtInfo.getCC();
1728
1729  // If this type isn't canonical, get the canonical version of it.
1730  // The exception spec is not part of the canonical type.
1731  QualType Canonical;
1732  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
1733    llvm::SmallVector<QualType, 16> CanonicalArgs;
1734    CanonicalArgs.reserve(NumArgs);
1735    for (unsigned i = 0; i != NumArgs; ++i)
1736      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
1737
1738    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
1739    if (CanonicalEPI.HasExceptionSpec) {
1740      CanonicalEPI.HasExceptionSpec = false;
1741      CanonicalEPI.HasAnyExceptionSpec = false;
1742      CanonicalEPI.NumExceptions = 0;
1743    }
1744    CanonicalEPI.ExtInfo
1745      = CanonicalEPI.ExtInfo.withCallingConv(getCanonicalCallConv(CallConv));
1746
1747    Canonical = getFunctionType(getCanonicalType(ResultTy),
1748                                CanonicalArgs.data(), NumArgs,
1749                                CanonicalEPI);
1750
1751    // Get the new insert position for the node we care about.
1752    FunctionProtoType *NewIP =
1753      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1754    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1755  }
1756
1757  // FunctionProtoType objects are allocated with extra bytes after them
1758  // for two variable size arrays (for parameter and exception types) at the
1759  // end of them.
1760  size_t Size = sizeof(FunctionProtoType) +
1761                NumArgs * sizeof(QualType) +
1762                EPI.NumExceptions * sizeof(QualType);
1763  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
1764  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, Canonical, EPI);
1765  Types.push_back(FTP);
1766  FunctionProtoTypes.InsertNode(FTP, InsertPos);
1767  return QualType(FTP, 0);
1768}
1769
1770#ifndef NDEBUG
1771static bool NeedsInjectedClassNameType(const RecordDecl *D) {
1772  if (!isa<CXXRecordDecl>(D)) return false;
1773  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
1774  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
1775    return true;
1776  if (RD->getDescribedClassTemplate() &&
1777      !isa<ClassTemplateSpecializationDecl>(RD))
1778    return true;
1779  return false;
1780}
1781#endif
1782
1783/// getInjectedClassNameType - Return the unique reference to the
1784/// injected class name type for the specified templated declaration.
1785QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
1786                                              QualType TST) {
1787  assert(NeedsInjectedClassNameType(Decl));
1788  if (Decl->TypeForDecl) {
1789    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1790  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDeclaration()) {
1791    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
1792    Decl->TypeForDecl = PrevDecl->TypeForDecl;
1793    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1794  } else {
1795    Decl->TypeForDecl =
1796      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
1797    Types.push_back(Decl->TypeForDecl);
1798  }
1799  return QualType(Decl->TypeForDecl, 0);
1800}
1801
1802/// getTypeDeclType - Return the unique reference to the type for the
1803/// specified type declaration.
1804QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) {
1805  assert(Decl && "Passed null for Decl param");
1806  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
1807
1808  if (const TypedefDecl *Typedef = dyn_cast<TypedefDecl>(Decl))
1809    return getTypedefType(Typedef);
1810
1811  assert(!isa<TemplateTypeParmDecl>(Decl) &&
1812         "Template type parameter types are always available.");
1813
1814  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
1815    assert(!Record->getPreviousDeclaration() &&
1816           "struct/union has previous declaration");
1817    assert(!NeedsInjectedClassNameType(Record));
1818    return getRecordType(Record);
1819  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
1820    assert(!Enum->getPreviousDeclaration() &&
1821           "enum has previous declaration");
1822    return getEnumType(Enum);
1823  } else if (const UnresolvedUsingTypenameDecl *Using =
1824               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
1825    Decl->TypeForDecl = new (*this, TypeAlignment) UnresolvedUsingType(Using);
1826  } else
1827    llvm_unreachable("TypeDecl without a type?");
1828
1829  Types.push_back(Decl->TypeForDecl);
1830  return QualType(Decl->TypeForDecl, 0);
1831}
1832
1833/// getTypedefType - Return the unique reference to the type for the
1834/// specified typename decl.
1835QualType
1836ASTContext::getTypedefType(const TypedefDecl *Decl, QualType Canonical) {
1837  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1838
1839  if (Canonical.isNull())
1840    Canonical = getCanonicalType(Decl->getUnderlyingType());
1841  Decl->TypeForDecl = new(*this, TypeAlignment)
1842    TypedefType(Type::Typedef, Decl, Canonical);
1843  Types.push_back(Decl->TypeForDecl);
1844  return QualType(Decl->TypeForDecl, 0);
1845}
1846
1847QualType ASTContext::getRecordType(const RecordDecl *Decl) {
1848  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1849
1850  if (const RecordDecl *PrevDecl = Decl->getPreviousDeclaration())
1851    if (PrevDecl->TypeForDecl)
1852      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1853
1854  Decl->TypeForDecl = new (*this, TypeAlignment) RecordType(Decl);
1855  Types.push_back(Decl->TypeForDecl);
1856  return QualType(Decl->TypeForDecl, 0);
1857}
1858
1859QualType ASTContext::getEnumType(const EnumDecl *Decl) {
1860  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1861
1862  if (const EnumDecl *PrevDecl = Decl->getPreviousDeclaration())
1863    if (PrevDecl->TypeForDecl)
1864      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1865
1866  Decl->TypeForDecl = new (*this, TypeAlignment) EnumType(Decl);
1867  Types.push_back(Decl->TypeForDecl);
1868  return QualType(Decl->TypeForDecl, 0);
1869}
1870
1871/// \brief Retrieve a substitution-result type.
1872QualType
1873ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
1874                                         QualType Replacement) {
1875  assert(Replacement.isCanonical()
1876         && "replacement types must always be canonical");
1877
1878  llvm::FoldingSetNodeID ID;
1879  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
1880  void *InsertPos = 0;
1881  SubstTemplateTypeParmType *SubstParm
1882    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1883
1884  if (!SubstParm) {
1885    SubstParm = new (*this, TypeAlignment)
1886      SubstTemplateTypeParmType(Parm, Replacement);
1887    Types.push_back(SubstParm);
1888    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
1889  }
1890
1891  return QualType(SubstParm, 0);
1892}
1893
1894/// \brief Retrieve the template type parameter type for a template
1895/// parameter or parameter pack with the given depth, index, and (optionally)
1896/// name.
1897QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
1898                                             bool ParameterPack,
1899                                             IdentifierInfo *Name) {
1900  llvm::FoldingSetNodeID ID;
1901  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, Name);
1902  void *InsertPos = 0;
1903  TemplateTypeParmType *TypeParm
1904    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1905
1906  if (TypeParm)
1907    return QualType(TypeParm, 0);
1908
1909  if (Name) {
1910    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
1911    TypeParm = new (*this, TypeAlignment)
1912      TemplateTypeParmType(Depth, Index, ParameterPack, Name, Canon);
1913
1914    TemplateTypeParmType *TypeCheck
1915      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1916    assert(!TypeCheck && "Template type parameter canonical type broken");
1917    (void)TypeCheck;
1918  } else
1919    TypeParm = new (*this, TypeAlignment)
1920      TemplateTypeParmType(Depth, Index, ParameterPack);
1921
1922  Types.push_back(TypeParm);
1923  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
1924
1925  return QualType(TypeParm, 0);
1926}
1927
1928TypeSourceInfo *
1929ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
1930                                              SourceLocation NameLoc,
1931                                        const TemplateArgumentListInfo &Args,
1932                                              QualType CanonType) {
1933  QualType TST = getTemplateSpecializationType(Name, Args, CanonType);
1934
1935  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
1936  TemplateSpecializationTypeLoc TL
1937    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
1938  TL.setTemplateNameLoc(NameLoc);
1939  TL.setLAngleLoc(Args.getLAngleLoc());
1940  TL.setRAngleLoc(Args.getRAngleLoc());
1941  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
1942    TL.setArgLocInfo(i, Args[i].getLocInfo());
1943  return DI;
1944}
1945
1946QualType
1947ASTContext::getTemplateSpecializationType(TemplateName Template,
1948                                          const TemplateArgumentListInfo &Args,
1949                                          QualType Canon) {
1950  unsigned NumArgs = Args.size();
1951
1952  llvm::SmallVector<TemplateArgument, 4> ArgVec;
1953  ArgVec.reserve(NumArgs);
1954  for (unsigned i = 0; i != NumArgs; ++i)
1955    ArgVec.push_back(Args[i].getArgument());
1956
1957  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
1958                                       Canon);
1959}
1960
1961QualType
1962ASTContext::getTemplateSpecializationType(TemplateName Template,
1963                                          const TemplateArgument *Args,
1964                                          unsigned NumArgs,
1965                                          QualType Canon) {
1966  if (!Canon.isNull())
1967    Canon = getCanonicalType(Canon);
1968  else
1969    Canon = getCanonicalTemplateSpecializationType(Template, Args, NumArgs);
1970
1971  // Allocate the (non-canonical) template specialization type, but don't
1972  // try to unique it: these types typically have location information that
1973  // we don't unique and don't want to lose.
1974  void *Mem = Allocate((sizeof(TemplateSpecializationType) +
1975                        sizeof(TemplateArgument) * NumArgs),
1976                       TypeAlignment);
1977  TemplateSpecializationType *Spec
1978    = new (Mem) TemplateSpecializationType(Template,
1979                                           Args, NumArgs,
1980                                           Canon);
1981
1982  Types.push_back(Spec);
1983  return QualType(Spec, 0);
1984}
1985
1986QualType
1987ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
1988                                                   const TemplateArgument *Args,
1989                                                   unsigned NumArgs) {
1990  // Build the canonical template specialization type.
1991  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
1992  llvm::SmallVector<TemplateArgument, 4> CanonArgs;
1993  CanonArgs.reserve(NumArgs);
1994  for (unsigned I = 0; I != NumArgs; ++I)
1995    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
1996
1997  // Determine whether this canonical template specialization type already
1998  // exists.
1999  llvm::FoldingSetNodeID ID;
2000  TemplateSpecializationType::Profile(ID, CanonTemplate,
2001                                      CanonArgs.data(), NumArgs, *this);
2002
2003  void *InsertPos = 0;
2004  TemplateSpecializationType *Spec
2005    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2006
2007  if (!Spec) {
2008    // Allocate a new canonical template specialization type.
2009    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2010                          sizeof(TemplateArgument) * NumArgs),
2011                         TypeAlignment);
2012    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
2013                                                CanonArgs.data(), NumArgs,
2014                                                QualType());
2015    Types.push_back(Spec);
2016    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
2017  }
2018
2019  assert(Spec->isDependentType() &&
2020         "Non-dependent template-id type must have a canonical type");
2021  return QualType(Spec, 0);
2022}
2023
2024QualType
2025ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
2026                              NestedNameSpecifier *NNS,
2027                              QualType NamedType) {
2028  llvm::FoldingSetNodeID ID;
2029  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2030
2031  void *InsertPos = 0;
2032  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2033  if (T)
2034    return QualType(T, 0);
2035
2036  QualType Canon = NamedType;
2037  if (!Canon.isCanonical()) {
2038    Canon = getCanonicalType(NamedType);
2039    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2040    assert(!CheckT && "Elaborated canonical type broken");
2041    (void)CheckT;
2042  }
2043
2044  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2045  Types.push_back(T);
2046  ElaboratedTypes.InsertNode(T, InsertPos);
2047  return QualType(T, 0);
2048}
2049
2050QualType
2051ASTContext::getParenType(QualType InnerType) {
2052  llvm::FoldingSetNodeID ID;
2053  ParenType::Profile(ID, InnerType);
2054
2055  void *InsertPos = 0;
2056  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2057  if (T)
2058    return QualType(T, 0);
2059
2060  QualType Canon = InnerType;
2061  if (!Canon.isCanonical()) {
2062    Canon = getCanonicalType(InnerType);
2063    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2064    assert(!CheckT && "Paren canonical type broken");
2065    (void)CheckT;
2066  }
2067
2068  T = new (*this) ParenType(InnerType, Canon);
2069  Types.push_back(T);
2070  ParenTypes.InsertNode(T, InsertPos);
2071  return QualType(T, 0);
2072}
2073
2074QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2075                                          NestedNameSpecifier *NNS,
2076                                          const IdentifierInfo *Name,
2077                                          QualType Canon) {
2078  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2079
2080  if (Canon.isNull()) {
2081    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2082    ElaboratedTypeKeyword CanonKeyword = Keyword;
2083    if (Keyword == ETK_None)
2084      CanonKeyword = ETK_Typename;
2085
2086    if (CanonNNS != NNS || CanonKeyword != Keyword)
2087      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2088  }
2089
2090  llvm::FoldingSetNodeID ID;
2091  DependentNameType::Profile(ID, Keyword, NNS, Name);
2092
2093  void *InsertPos = 0;
2094  DependentNameType *T
2095    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2096  if (T)
2097    return QualType(T, 0);
2098
2099  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2100  Types.push_back(T);
2101  DependentNameTypes.InsertNode(T, InsertPos);
2102  return QualType(T, 0);
2103}
2104
2105QualType
2106ASTContext::getDependentTemplateSpecializationType(
2107                                 ElaboratedTypeKeyword Keyword,
2108                                 NestedNameSpecifier *NNS,
2109                                 const IdentifierInfo *Name,
2110                                 const TemplateArgumentListInfo &Args) {
2111  // TODO: avoid this copy
2112  llvm::SmallVector<TemplateArgument, 16> ArgCopy;
2113  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2114    ArgCopy.push_back(Args[I].getArgument());
2115  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2116                                                ArgCopy.size(),
2117                                                ArgCopy.data());
2118}
2119
2120QualType
2121ASTContext::getDependentTemplateSpecializationType(
2122                                 ElaboratedTypeKeyword Keyword,
2123                                 NestedNameSpecifier *NNS,
2124                                 const IdentifierInfo *Name,
2125                                 unsigned NumArgs,
2126                                 const TemplateArgument *Args) {
2127  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2128
2129  llvm::FoldingSetNodeID ID;
2130  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2131                                               Name, NumArgs, Args);
2132
2133  void *InsertPos = 0;
2134  DependentTemplateSpecializationType *T
2135    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2136  if (T)
2137    return QualType(T, 0);
2138
2139  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2140
2141  ElaboratedTypeKeyword CanonKeyword = Keyword;
2142  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2143
2144  bool AnyNonCanonArgs = false;
2145  llvm::SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2146  for (unsigned I = 0; I != NumArgs; ++I) {
2147    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2148    if (!CanonArgs[I].structurallyEquals(Args[I]))
2149      AnyNonCanonArgs = true;
2150  }
2151
2152  QualType Canon;
2153  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2154    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2155                                                   Name, NumArgs,
2156                                                   CanonArgs.data());
2157
2158    // Find the insert position again.
2159    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2160  }
2161
2162  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2163                        sizeof(TemplateArgument) * NumArgs),
2164                       TypeAlignment);
2165  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2166                                                    Name, NumArgs, Args, Canon);
2167  Types.push_back(T);
2168  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2169  return QualType(T, 0);
2170}
2171
2172QualType ASTContext::getPackExpansionType(QualType Pattern) {
2173  llvm::FoldingSetNodeID ID;
2174  PackExpansionType::Profile(ID, Pattern);
2175
2176  assert(Pattern->containsUnexpandedParameterPack() &&
2177         "Pack expansions must expand one or more parameter packs");
2178  void *InsertPos = 0;
2179  PackExpansionType *T
2180    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2181  if (T)
2182    return QualType(T, 0);
2183
2184  QualType Canon;
2185  if (!Pattern.isCanonical()) {
2186    Canon = getPackExpansionType(getCanonicalType(Pattern));
2187
2188    // Find the insert position again.
2189    PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
2190  }
2191
2192  T = new (*this) PackExpansionType(Pattern, Canon);
2193  Types.push_back(T);
2194  PackExpansionTypes.InsertNode(T, InsertPos);
2195  return QualType(T, 0);
2196}
2197
2198/// CmpProtocolNames - Comparison predicate for sorting protocols
2199/// alphabetically.
2200static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2201                            const ObjCProtocolDecl *RHS) {
2202  return LHS->getDeclName() < RHS->getDeclName();
2203}
2204
2205static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2206                                unsigned NumProtocols) {
2207  if (NumProtocols == 0) return true;
2208
2209  for (unsigned i = 1; i != NumProtocols; ++i)
2210    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]))
2211      return false;
2212  return true;
2213}
2214
2215static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2216                                   unsigned &NumProtocols) {
2217  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2218
2219  // Sort protocols, keyed by name.
2220  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2221
2222  // Remove duplicates.
2223  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2224  NumProtocols = ProtocolsEnd-Protocols;
2225}
2226
2227QualType ASTContext::getObjCObjectType(QualType BaseType,
2228                                       ObjCProtocolDecl * const *Protocols,
2229                                       unsigned NumProtocols) {
2230  // If the base type is an interface and there aren't any protocols
2231  // to add, then the interface type will do just fine.
2232  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2233    return BaseType;
2234
2235  // Look in the folding set for an existing type.
2236  llvm::FoldingSetNodeID ID;
2237  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2238  void *InsertPos = 0;
2239  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2240    return QualType(QT, 0);
2241
2242  // Build the canonical type, which has the canonical base type and
2243  // a sorted-and-uniqued list of protocols.
2244  QualType Canonical;
2245  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2246  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2247    if (!ProtocolsSorted) {
2248      llvm::SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2249                                                     Protocols + NumProtocols);
2250      unsigned UniqueCount = NumProtocols;
2251
2252      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2253      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2254                                    &Sorted[0], UniqueCount);
2255    } else {
2256      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2257                                    Protocols, NumProtocols);
2258    }
2259
2260    // Regenerate InsertPos.
2261    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2262  }
2263
2264  unsigned Size = sizeof(ObjCObjectTypeImpl);
2265  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2266  void *Mem = Allocate(Size, TypeAlignment);
2267  ObjCObjectTypeImpl *T =
2268    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2269
2270  Types.push_back(T);
2271  ObjCObjectTypes.InsertNode(T, InsertPos);
2272  return QualType(T, 0);
2273}
2274
2275/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2276/// the given object type.
2277QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) {
2278  llvm::FoldingSetNodeID ID;
2279  ObjCObjectPointerType::Profile(ID, ObjectT);
2280
2281  void *InsertPos = 0;
2282  if (ObjCObjectPointerType *QT =
2283              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2284    return QualType(QT, 0);
2285
2286  // Find the canonical object type.
2287  QualType Canonical;
2288  if (!ObjectT.isCanonical()) {
2289    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2290
2291    // Regenerate InsertPos.
2292    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2293  }
2294
2295  // No match.
2296  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2297  ObjCObjectPointerType *QType =
2298    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2299
2300  Types.push_back(QType);
2301  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2302  return QualType(QType, 0);
2303}
2304
2305/// getObjCInterfaceType - Return the unique reference to the type for the
2306/// specified ObjC interface decl. The list of protocols is optional.
2307QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl) {
2308  if (Decl->TypeForDecl)
2309    return QualType(Decl->TypeForDecl, 0);
2310
2311  // FIXME: redeclarations?
2312  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2313  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2314  Decl->TypeForDecl = T;
2315  Types.push_back(T);
2316  return QualType(T, 0);
2317}
2318
2319/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2320/// TypeOfExprType AST's (since expression's are never shared). For example,
2321/// multiple declarations that refer to "typeof(x)" all contain different
2322/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2323/// on canonical type's (which are always unique).
2324QualType ASTContext::getTypeOfExprType(Expr *tofExpr) {
2325  TypeOfExprType *toe;
2326  if (tofExpr->isTypeDependent()) {
2327    llvm::FoldingSetNodeID ID;
2328    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2329
2330    void *InsertPos = 0;
2331    DependentTypeOfExprType *Canon
2332      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2333    if (Canon) {
2334      // We already have a "canonical" version of an identical, dependent
2335      // typeof(expr) type. Use that as our canonical type.
2336      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2337                                          QualType((TypeOfExprType*)Canon, 0));
2338    }
2339    else {
2340      // Build a new, canonical typeof(expr) type.
2341      Canon
2342        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2343      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2344      toe = Canon;
2345    }
2346  } else {
2347    QualType Canonical = getCanonicalType(tofExpr->getType());
2348    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2349  }
2350  Types.push_back(toe);
2351  return QualType(toe, 0);
2352}
2353
2354/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2355/// TypeOfType AST's. The only motivation to unique these nodes would be
2356/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2357/// an issue. This doesn't effect the type checker, since it operates
2358/// on canonical type's (which are always unique).
2359QualType ASTContext::getTypeOfType(QualType tofType) {
2360  QualType Canonical = getCanonicalType(tofType);
2361  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2362  Types.push_back(tot);
2363  return QualType(tot, 0);
2364}
2365
2366/// getDecltypeForExpr - Given an expr, will return the decltype for that
2367/// expression, according to the rules in C++0x [dcl.type.simple]p4
2368static QualType getDecltypeForExpr(const Expr *e, ASTContext &Context) {
2369  if (e->isTypeDependent())
2370    return Context.DependentTy;
2371
2372  // If e is an id expression or a class member access, decltype(e) is defined
2373  // as the type of the entity named by e.
2374  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2375    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2376      return VD->getType();
2377  }
2378  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2379    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2380      return FD->getType();
2381  }
2382  // If e is a function call or an invocation of an overloaded operator,
2383  // (parentheses around e are ignored), decltype(e) is defined as the
2384  // return type of that function.
2385  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2386    return CE->getCallReturnType();
2387
2388  QualType T = e->getType();
2389
2390  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2391  // defined as T&, otherwise decltype(e) is defined as T.
2392  if (e->isLValue())
2393    T = Context.getLValueReferenceType(T);
2394
2395  return T;
2396}
2397
2398/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2399/// DecltypeType AST's. The only motivation to unique these nodes would be
2400/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2401/// an issue. This doesn't effect the type checker, since it operates
2402/// on canonical type's (which are always unique).
2403QualType ASTContext::getDecltypeType(Expr *e) {
2404  DecltypeType *dt;
2405  if (e->isTypeDependent()) {
2406    llvm::FoldingSetNodeID ID;
2407    DependentDecltypeType::Profile(ID, *this, e);
2408
2409    void *InsertPos = 0;
2410    DependentDecltypeType *Canon
2411      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2412    if (Canon) {
2413      // We already have a "canonical" version of an equivalent, dependent
2414      // decltype type. Use that as our canonical type.
2415      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2416                                       QualType((DecltypeType*)Canon, 0));
2417    }
2418    else {
2419      // Build a new, canonical typeof(expr) type.
2420      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2421      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2422      dt = Canon;
2423    }
2424  } else {
2425    QualType T = getDecltypeForExpr(e, *this);
2426    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2427  }
2428  Types.push_back(dt);
2429  return QualType(dt, 0);
2430}
2431
2432/// getTagDeclType - Return the unique reference to the type for the
2433/// specified TagDecl (struct/union/class/enum) decl.
2434QualType ASTContext::getTagDeclType(const TagDecl *Decl) {
2435  assert (Decl);
2436  // FIXME: What is the design on getTagDeclType when it requires casting
2437  // away const?  mutable?
2438  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2439}
2440
2441/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2442/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2443/// needs to agree with the definition in <stddef.h>.
2444CanQualType ASTContext::getSizeType() const {
2445  return getFromTargetType(Target.getSizeType());
2446}
2447
2448/// getSignedWCharType - Return the type of "signed wchar_t".
2449/// Used when in C++, as a GCC extension.
2450QualType ASTContext::getSignedWCharType() const {
2451  // FIXME: derive from "Target" ?
2452  return WCharTy;
2453}
2454
2455/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
2456/// Used when in C++, as a GCC extension.
2457QualType ASTContext::getUnsignedWCharType() const {
2458  // FIXME: derive from "Target" ?
2459  return UnsignedIntTy;
2460}
2461
2462/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
2463/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
2464QualType ASTContext::getPointerDiffType() const {
2465  return getFromTargetType(Target.getPtrDiffType(0));
2466}
2467
2468//===----------------------------------------------------------------------===//
2469//                              Type Operators
2470//===----------------------------------------------------------------------===//
2471
2472CanQualType ASTContext::getCanonicalParamType(QualType T) {
2473  // Push qualifiers into arrays, and then discard any remaining
2474  // qualifiers.
2475  T = getCanonicalType(T);
2476  T = getVariableArrayDecayedType(T);
2477  const Type *Ty = T.getTypePtr();
2478  QualType Result;
2479  if (isa<ArrayType>(Ty)) {
2480    Result = getArrayDecayedType(QualType(Ty,0));
2481  } else if (isa<FunctionType>(Ty)) {
2482    Result = getPointerType(QualType(Ty, 0));
2483  } else {
2484    Result = QualType(Ty, 0);
2485  }
2486
2487  return CanQualType::CreateUnsafe(Result);
2488}
2489
2490/// getCanonicalType - Return the canonical (structural) type corresponding to
2491/// the specified potentially non-canonical type.  The non-canonical version
2492/// of a type may have many "decorated" versions of types.  Decorators can
2493/// include typedefs, 'typeof' operators, etc. The returned type is guaranteed
2494/// to be free of any of these, allowing two canonical types to be compared
2495/// for exact equality with a simple pointer comparison.
2496CanQualType ASTContext::getCanonicalType(QualType T) {
2497  QualifierCollector Quals;
2498  const Type *Ptr = Quals.strip(T);
2499  QualType CanType = Ptr->getCanonicalTypeInternal();
2500
2501  // The canonical internal type will be the canonical type *except*
2502  // that we push type qualifiers down through array types.
2503
2504  // If there are no new qualifiers to push down, stop here.
2505  if (!Quals.hasQualifiers())
2506    return CanQualType::CreateUnsafe(CanType);
2507
2508  // If the type qualifiers are on an array type, get the canonical
2509  // type of the array with the qualifiers applied to the element
2510  // type.
2511  ArrayType *AT = dyn_cast<ArrayType>(CanType);
2512  if (!AT)
2513    return CanQualType::CreateUnsafe(getQualifiedType(CanType, Quals));
2514
2515  // Get the canonical version of the element with the extra qualifiers on it.
2516  // This can recursively sink qualifiers through multiple levels of arrays.
2517  QualType NewEltTy = getQualifiedType(AT->getElementType(), Quals);
2518  NewEltTy = getCanonicalType(NewEltTy);
2519
2520  if (ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
2521    return CanQualType::CreateUnsafe(
2522             getConstantArrayType(NewEltTy, CAT->getSize(),
2523                                  CAT->getSizeModifier(),
2524                                  CAT->getIndexTypeCVRQualifiers()));
2525  if (IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT))
2526    return CanQualType::CreateUnsafe(
2527             getIncompleteArrayType(NewEltTy, IAT->getSizeModifier(),
2528                                    IAT->getIndexTypeCVRQualifiers()));
2529
2530  if (DependentSizedArrayType *DSAT = dyn_cast<DependentSizedArrayType>(AT))
2531    return CanQualType::CreateUnsafe(
2532             getDependentSizedArrayType(NewEltTy,
2533                                        DSAT->getSizeExpr(),
2534                                        DSAT->getSizeModifier(),
2535                                        DSAT->getIndexTypeCVRQualifiers(),
2536                        DSAT->getBracketsRange())->getCanonicalTypeInternal());
2537
2538  VariableArrayType *VAT = cast<VariableArrayType>(AT);
2539  return CanQualType::CreateUnsafe(getVariableArrayType(NewEltTy,
2540                                                        VAT->getSizeExpr(),
2541                                                        VAT->getSizeModifier(),
2542                                              VAT->getIndexTypeCVRQualifiers(),
2543                                                     VAT->getBracketsRange()));
2544}
2545
2546QualType ASTContext::getUnqualifiedArrayType(QualType T,
2547                                             Qualifiers &Quals) {
2548  Quals = T.getQualifiers();
2549  const ArrayType *AT = getAsArrayType(T);
2550  if (!AT) {
2551    return T.getUnqualifiedType();
2552  }
2553
2554  QualType Elt = AT->getElementType();
2555  QualType UnqualElt = getUnqualifiedArrayType(Elt, Quals);
2556  if (Elt == UnqualElt)
2557    return T;
2558
2559  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
2560    return getConstantArrayType(UnqualElt, CAT->getSize(),
2561                                CAT->getSizeModifier(), 0);
2562  }
2563
2564  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
2565    return getIncompleteArrayType(UnqualElt, IAT->getSizeModifier(), 0);
2566  }
2567
2568  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
2569    return getVariableArrayType(UnqualElt,
2570                                VAT->getSizeExpr(),
2571                                VAT->getSizeModifier(),
2572                                VAT->getIndexTypeCVRQualifiers(),
2573                                VAT->getBracketsRange());
2574  }
2575
2576  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
2577  return getDependentSizedArrayType(UnqualElt, DSAT->getSizeExpr(),
2578                                    DSAT->getSizeModifier(), 0,
2579                                    SourceRange());
2580}
2581
2582/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
2583/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
2584/// they point to and return true. If T1 and T2 aren't pointer types
2585/// or pointer-to-member types, or if they are not similar at this
2586/// level, returns false and leaves T1 and T2 unchanged. Top-level
2587/// qualifiers on T1 and T2 are ignored. This function will typically
2588/// be called in a loop that successively "unwraps" pointer and
2589/// pointer-to-member types to compare them at each level.
2590bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
2591  const PointerType *T1PtrType = T1->getAs<PointerType>(),
2592                    *T2PtrType = T2->getAs<PointerType>();
2593  if (T1PtrType && T2PtrType) {
2594    T1 = T1PtrType->getPointeeType();
2595    T2 = T2PtrType->getPointeeType();
2596    return true;
2597  }
2598
2599  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
2600                          *T2MPType = T2->getAs<MemberPointerType>();
2601  if (T1MPType && T2MPType &&
2602      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
2603                             QualType(T2MPType->getClass(), 0))) {
2604    T1 = T1MPType->getPointeeType();
2605    T2 = T2MPType->getPointeeType();
2606    return true;
2607  }
2608
2609  if (getLangOptions().ObjC1) {
2610    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
2611                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
2612    if (T1OPType && T2OPType) {
2613      T1 = T1OPType->getPointeeType();
2614      T2 = T2OPType->getPointeeType();
2615      return true;
2616    }
2617  }
2618
2619  // FIXME: Block pointers, too?
2620
2621  return false;
2622}
2623
2624DeclarationNameInfo ASTContext::getNameForTemplate(TemplateName Name,
2625                                                   SourceLocation NameLoc) {
2626  if (TemplateDecl *TD = Name.getAsTemplateDecl())
2627    // DNInfo work in progress: CHECKME: what about DNLoc?
2628    return DeclarationNameInfo(TD->getDeclName(), NameLoc);
2629
2630  if (DependentTemplateName *DTN = Name.getAsDependentTemplateName()) {
2631    DeclarationName DName;
2632    if (DTN->isIdentifier()) {
2633      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
2634      return DeclarationNameInfo(DName, NameLoc);
2635    } else {
2636      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
2637      // DNInfo work in progress: FIXME: source locations?
2638      DeclarationNameLoc DNLoc;
2639      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
2640      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
2641      return DeclarationNameInfo(DName, NameLoc, DNLoc);
2642    }
2643  }
2644
2645  OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
2646  assert(Storage);
2647  // DNInfo work in progress: CHECKME: what about DNLoc?
2648  return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
2649}
2650
2651TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) {
2652  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
2653    if (TemplateTemplateParmDecl *TTP
2654                              = dyn_cast<TemplateTemplateParmDecl>(Template))
2655      Template = getCanonicalTemplateTemplateParmDecl(TTP);
2656
2657    // The canonical template name is the canonical template declaration.
2658    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
2659  }
2660
2661  assert(!Name.getAsOverloadedTemplate());
2662
2663  DependentTemplateName *DTN = Name.getAsDependentTemplateName();
2664  assert(DTN && "Non-dependent template names must refer to template decls.");
2665  return DTN->CanonicalTemplateName;
2666}
2667
2668bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
2669  X = getCanonicalTemplateName(X);
2670  Y = getCanonicalTemplateName(Y);
2671  return X.getAsVoidPointer() == Y.getAsVoidPointer();
2672}
2673
2674TemplateArgument
2675ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) {
2676  switch (Arg.getKind()) {
2677    case TemplateArgument::Null:
2678      return Arg;
2679
2680    case TemplateArgument::Expression:
2681      return Arg;
2682
2683    case TemplateArgument::Declaration:
2684      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
2685
2686    case TemplateArgument::Template:
2687      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
2688
2689    case TemplateArgument::Integral:
2690      return TemplateArgument(*Arg.getAsIntegral(),
2691                              getCanonicalType(Arg.getIntegralType()));
2692
2693    case TemplateArgument::Type:
2694      return TemplateArgument(getCanonicalType(Arg.getAsType()));
2695
2696    case TemplateArgument::Pack: {
2697      if (Arg.pack_size() == 0)
2698        return Arg;
2699
2700      TemplateArgument *CanonArgs
2701        = new (*this) TemplateArgument[Arg.pack_size()];
2702      unsigned Idx = 0;
2703      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
2704                                        AEnd = Arg.pack_end();
2705           A != AEnd; (void)++A, ++Idx)
2706        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
2707
2708      return TemplateArgument(CanonArgs, Arg.pack_size());
2709    }
2710  }
2711
2712  // Silence GCC warning
2713  assert(false && "Unhandled template argument kind");
2714  return TemplateArgument();
2715}
2716
2717NestedNameSpecifier *
2718ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) {
2719  if (!NNS)
2720    return 0;
2721
2722  switch (NNS->getKind()) {
2723  case NestedNameSpecifier::Identifier:
2724    // Canonicalize the prefix but keep the identifier the same.
2725    return NestedNameSpecifier::Create(*this,
2726                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
2727                                       NNS->getAsIdentifier());
2728
2729  case NestedNameSpecifier::Namespace:
2730    // A namespace is canonical; build a nested-name-specifier with
2731    // this namespace and no prefix.
2732    return NestedNameSpecifier::Create(*this, 0, NNS->getAsNamespace());
2733
2734  case NestedNameSpecifier::TypeSpec:
2735  case NestedNameSpecifier::TypeSpecWithTemplate: {
2736    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
2737
2738    // If we have some kind of dependent-named type (e.g., "typename T::type"),
2739    // break it apart into its prefix and identifier, then reconsititute those
2740    // as the canonical nested-name-specifier. This is required to canonicalize
2741    // a dependent nested-name-specifier involving typedefs of dependent-name
2742    // types, e.g.,
2743    //   typedef typename T::type T1;
2744    //   typedef typename T1::type T2;
2745    if (const DependentNameType *DNT = T->getAs<DependentNameType>()) {
2746      NestedNameSpecifier *Prefix
2747        = getCanonicalNestedNameSpecifier(DNT->getQualifier());
2748      return NestedNameSpecifier::Create(*this, Prefix,
2749                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
2750    }
2751
2752    // Do the same thing as above, but with dependent-named specializations.
2753    if (const DependentTemplateSpecializationType *DTST
2754          = T->getAs<DependentTemplateSpecializationType>()) {
2755      NestedNameSpecifier *Prefix
2756        = getCanonicalNestedNameSpecifier(DTST->getQualifier());
2757      TemplateName Name
2758        = getDependentTemplateName(Prefix, DTST->getIdentifier());
2759      T = getTemplateSpecializationType(Name,
2760                                        DTST->getArgs(), DTST->getNumArgs());
2761      T = getCanonicalType(T);
2762    }
2763
2764    return NestedNameSpecifier::Create(*this, 0, false, T.getTypePtr());
2765  }
2766
2767  case NestedNameSpecifier::Global:
2768    // The global specifier is canonical and unique.
2769    return NNS;
2770  }
2771
2772  // Required to silence a GCC warning
2773  return 0;
2774}
2775
2776
2777const ArrayType *ASTContext::getAsArrayType(QualType T) {
2778  // Handle the non-qualified case efficiently.
2779  if (!T.hasLocalQualifiers()) {
2780    // Handle the common positive case fast.
2781    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
2782      return AT;
2783  }
2784
2785  // Handle the common negative case fast.
2786  QualType CType = T->getCanonicalTypeInternal();
2787  if (!isa<ArrayType>(CType))
2788    return 0;
2789
2790  // Apply any qualifiers from the array type to the element type.  This
2791  // implements C99 6.7.3p8: "If the specification of an array type includes
2792  // any type qualifiers, the element type is so qualified, not the array type."
2793
2794  // If we get here, we either have type qualifiers on the type, or we have
2795  // sugar such as a typedef in the way.  If we have type qualifiers on the type
2796  // we must propagate them down into the element type.
2797
2798  QualifierCollector Qs;
2799  const Type *Ty = Qs.strip(T.getDesugaredType(*this));
2800
2801  // If we have a simple case, just return now.
2802  const ArrayType *ATy = dyn_cast<ArrayType>(Ty);
2803  if (ATy == 0 || Qs.empty())
2804    return ATy;
2805
2806  // Otherwise, we have an array and we have qualifiers on it.  Push the
2807  // qualifiers into the array element type and return a new array type.
2808  // Get the canonical version of the element with the extra qualifiers on it.
2809  // This can recursively sink qualifiers through multiple levels of arrays.
2810  QualType NewEltTy = getQualifiedType(ATy->getElementType(), Qs);
2811
2812  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
2813    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
2814                                                CAT->getSizeModifier(),
2815                                           CAT->getIndexTypeCVRQualifiers()));
2816  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
2817    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
2818                                                  IAT->getSizeModifier(),
2819                                           IAT->getIndexTypeCVRQualifiers()));
2820
2821  if (const DependentSizedArrayType *DSAT
2822        = dyn_cast<DependentSizedArrayType>(ATy))
2823    return cast<ArrayType>(
2824                     getDependentSizedArrayType(NewEltTy,
2825                                                DSAT->getSizeExpr(),
2826                                                DSAT->getSizeModifier(),
2827                                              DSAT->getIndexTypeCVRQualifiers(),
2828                                                DSAT->getBracketsRange()));
2829
2830  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
2831  return cast<ArrayType>(getVariableArrayType(NewEltTy,
2832                                              VAT->getSizeExpr(),
2833                                              VAT->getSizeModifier(),
2834                                              VAT->getIndexTypeCVRQualifiers(),
2835                                              VAT->getBracketsRange()));
2836}
2837
2838/// getArrayDecayedType - Return the properly qualified result of decaying the
2839/// specified array type to a pointer.  This operation is non-trivial when
2840/// handling typedefs etc.  The canonical type of "T" must be an array type,
2841/// this returns a pointer to a properly qualified element of the array.
2842///
2843/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
2844QualType ASTContext::getArrayDecayedType(QualType Ty) {
2845  // Get the element type with 'getAsArrayType' so that we don't lose any
2846  // typedefs in the element type of the array.  This also handles propagation
2847  // of type qualifiers from the array type into the element type if present
2848  // (C99 6.7.3p8).
2849  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
2850  assert(PrettyArrayType && "Not an array type!");
2851
2852  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
2853
2854  // int x[restrict 4] ->  int *restrict
2855  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
2856}
2857
2858QualType ASTContext::getBaseElementType(QualType QT) {
2859  QualifierCollector Qs;
2860  while (const ArrayType *AT = getAsArrayType(QualType(Qs.strip(QT), 0)))
2861    QT = AT->getElementType();
2862  return Qs.apply(*this, QT);
2863}
2864
2865QualType ASTContext::getBaseElementType(const ArrayType *AT) {
2866  QualType ElemTy = AT->getElementType();
2867
2868  if (const ArrayType *AT = getAsArrayType(ElemTy))
2869    return getBaseElementType(AT);
2870
2871  return ElemTy;
2872}
2873
2874/// getConstantArrayElementCount - Returns number of constant array elements.
2875uint64_t
2876ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
2877  uint64_t ElementCount = 1;
2878  do {
2879    ElementCount *= CA->getSize().getZExtValue();
2880    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
2881  } while (CA);
2882  return ElementCount;
2883}
2884
2885/// getFloatingRank - Return a relative rank for floating point types.
2886/// This routine will assert if passed a built-in type that isn't a float.
2887static FloatingRank getFloatingRank(QualType T) {
2888  if (const ComplexType *CT = T->getAs<ComplexType>())
2889    return getFloatingRank(CT->getElementType());
2890
2891  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
2892  switch (T->getAs<BuiltinType>()->getKind()) {
2893  default: assert(0 && "getFloatingRank(): not a floating type");
2894  case BuiltinType::Float:      return FloatRank;
2895  case BuiltinType::Double:     return DoubleRank;
2896  case BuiltinType::LongDouble: return LongDoubleRank;
2897  }
2898}
2899
2900/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
2901/// point or a complex type (based on typeDomain/typeSize).
2902/// 'typeDomain' is a real floating point or complex type.
2903/// 'typeSize' is a real floating point or complex type.
2904QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
2905                                                       QualType Domain) const {
2906  FloatingRank EltRank = getFloatingRank(Size);
2907  if (Domain->isComplexType()) {
2908    switch (EltRank) {
2909    default: assert(0 && "getFloatingRank(): illegal value for rank");
2910    case FloatRank:      return FloatComplexTy;
2911    case DoubleRank:     return DoubleComplexTy;
2912    case LongDoubleRank: return LongDoubleComplexTy;
2913    }
2914  }
2915
2916  assert(Domain->isRealFloatingType() && "Unknown domain!");
2917  switch (EltRank) {
2918  default: assert(0 && "getFloatingRank(): illegal value for rank");
2919  case FloatRank:      return FloatTy;
2920  case DoubleRank:     return DoubleTy;
2921  case LongDoubleRank: return LongDoubleTy;
2922  }
2923}
2924
2925/// getFloatingTypeOrder - Compare the rank of the two specified floating
2926/// point types, ignoring the domain of the type (i.e. 'double' ==
2927/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2928/// LHS < RHS, return -1.
2929int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) {
2930  FloatingRank LHSR = getFloatingRank(LHS);
2931  FloatingRank RHSR = getFloatingRank(RHS);
2932
2933  if (LHSR == RHSR)
2934    return 0;
2935  if (LHSR > RHSR)
2936    return 1;
2937  return -1;
2938}
2939
2940/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
2941/// routine will assert if passed a built-in type that isn't an integer or enum,
2942/// or if it is not canonicalized.
2943unsigned ASTContext::getIntegerRank(Type *T) {
2944  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
2945  if (EnumType* ET = dyn_cast<EnumType>(T))
2946    T = ET->getDecl()->getPromotionType().getTypePtr();
2947
2948  if (T->isSpecificBuiltinType(BuiltinType::WChar))
2949    T = getFromTargetType(Target.getWCharType()).getTypePtr();
2950
2951  if (T->isSpecificBuiltinType(BuiltinType::Char16))
2952    T = getFromTargetType(Target.getChar16Type()).getTypePtr();
2953
2954  if (T->isSpecificBuiltinType(BuiltinType::Char32))
2955    T = getFromTargetType(Target.getChar32Type()).getTypePtr();
2956
2957  switch (cast<BuiltinType>(T)->getKind()) {
2958  default: assert(0 && "getIntegerRank(): not a built-in integer");
2959  case BuiltinType::Bool:
2960    return 1 + (getIntWidth(BoolTy) << 3);
2961  case BuiltinType::Char_S:
2962  case BuiltinType::Char_U:
2963  case BuiltinType::SChar:
2964  case BuiltinType::UChar:
2965    return 2 + (getIntWidth(CharTy) << 3);
2966  case BuiltinType::Short:
2967  case BuiltinType::UShort:
2968    return 3 + (getIntWidth(ShortTy) << 3);
2969  case BuiltinType::Int:
2970  case BuiltinType::UInt:
2971    return 4 + (getIntWidth(IntTy) << 3);
2972  case BuiltinType::Long:
2973  case BuiltinType::ULong:
2974    return 5 + (getIntWidth(LongTy) << 3);
2975  case BuiltinType::LongLong:
2976  case BuiltinType::ULongLong:
2977    return 6 + (getIntWidth(LongLongTy) << 3);
2978  case BuiltinType::Int128:
2979  case BuiltinType::UInt128:
2980    return 7 + (getIntWidth(Int128Ty) << 3);
2981  }
2982}
2983
2984/// \brief Whether this is a promotable bitfield reference according
2985/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
2986///
2987/// \returns the type this bit-field will promote to, or NULL if no
2988/// promotion occurs.
2989QualType ASTContext::isPromotableBitField(Expr *E) {
2990  if (E->isTypeDependent() || E->isValueDependent())
2991    return QualType();
2992
2993  FieldDecl *Field = E->getBitField();
2994  if (!Field)
2995    return QualType();
2996
2997  QualType FT = Field->getType();
2998
2999  llvm::APSInt BitWidthAP = Field->getBitWidth()->EvaluateAsInt(*this);
3000  uint64_t BitWidth = BitWidthAP.getZExtValue();
3001  uint64_t IntSize = getTypeSize(IntTy);
3002  // GCC extension compatibility: if the bit-field size is less than or equal
3003  // to the size of int, it gets promoted no matter what its type is.
3004  // For instance, unsigned long bf : 4 gets promoted to signed int.
3005  if (BitWidth < IntSize)
3006    return IntTy;
3007
3008  if (BitWidth == IntSize)
3009    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
3010
3011  // Types bigger than int are not subject to promotions, and therefore act
3012  // like the base type.
3013  // FIXME: This doesn't quite match what gcc does, but what gcc does here
3014  // is ridiculous.
3015  return QualType();
3016}
3017
3018/// getPromotedIntegerType - Returns the type that Promotable will
3019/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
3020/// integer type.
3021QualType ASTContext::getPromotedIntegerType(QualType Promotable) {
3022  assert(!Promotable.isNull());
3023  assert(Promotable->isPromotableIntegerType());
3024  if (const EnumType *ET = Promotable->getAs<EnumType>())
3025    return ET->getDecl()->getPromotionType();
3026  if (Promotable->isSignedIntegerType())
3027    return IntTy;
3028  uint64_t PromotableSize = getTypeSize(Promotable);
3029  uint64_t IntSize = getTypeSize(IntTy);
3030  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3031  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3032}
3033
3034/// getIntegerTypeOrder - Returns the highest ranked integer type:
3035/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3036/// LHS < RHS, return -1.
3037int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) {
3038  Type *LHSC = getCanonicalType(LHS).getTypePtr();
3039  Type *RHSC = getCanonicalType(RHS).getTypePtr();
3040  if (LHSC == RHSC) return 0;
3041
3042  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3043  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3044
3045  unsigned LHSRank = getIntegerRank(LHSC);
3046  unsigned RHSRank = getIntegerRank(RHSC);
3047
3048  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3049    if (LHSRank == RHSRank) return 0;
3050    return LHSRank > RHSRank ? 1 : -1;
3051  }
3052
3053  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3054  if (LHSUnsigned) {
3055    // If the unsigned [LHS] type is larger, return it.
3056    if (LHSRank >= RHSRank)
3057      return 1;
3058
3059    // If the signed type can represent all values of the unsigned type, it
3060    // wins.  Because we are dealing with 2's complement and types that are
3061    // powers of two larger than each other, this is always safe.
3062    return -1;
3063  }
3064
3065  // If the unsigned [RHS] type is larger, return it.
3066  if (RHSRank >= LHSRank)
3067    return -1;
3068
3069  // If the signed type can represent all values of the unsigned type, it
3070  // wins.  Because we are dealing with 2's complement and types that are
3071  // powers of two larger than each other, this is always safe.
3072  return 1;
3073}
3074
3075static RecordDecl *
3076CreateRecordDecl(ASTContext &Ctx, RecordDecl::TagKind TK, DeclContext *DC,
3077                 SourceLocation L, IdentifierInfo *Id) {
3078  if (Ctx.getLangOptions().CPlusPlus)
3079    return CXXRecordDecl::Create(Ctx, TK, DC, L, Id);
3080  else
3081    return RecordDecl::Create(Ctx, TK, DC, L, Id);
3082}
3083
3084// getCFConstantStringType - Return the type used for constant CFStrings.
3085QualType ASTContext::getCFConstantStringType() {
3086  if (!CFConstantStringTypeDecl) {
3087    CFConstantStringTypeDecl =
3088      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3089                       &Idents.get("NSConstantString"));
3090    CFConstantStringTypeDecl->startDefinition();
3091
3092    QualType FieldTypes[4];
3093
3094    // const int *isa;
3095    FieldTypes[0] = getPointerType(IntTy.withConst());
3096    // int flags;
3097    FieldTypes[1] = IntTy;
3098    // const char *str;
3099    FieldTypes[2] = getPointerType(CharTy.withConst());
3100    // long length;
3101    FieldTypes[3] = LongTy;
3102
3103    // Create fields
3104    for (unsigned i = 0; i < 4; ++i) {
3105      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3106                                           SourceLocation(), 0,
3107                                           FieldTypes[i], /*TInfo=*/0,
3108                                           /*BitWidth=*/0,
3109                                           /*Mutable=*/false);
3110      Field->setAccess(AS_public);
3111      CFConstantStringTypeDecl->addDecl(Field);
3112    }
3113
3114    CFConstantStringTypeDecl->completeDefinition();
3115  }
3116
3117  return getTagDeclType(CFConstantStringTypeDecl);
3118}
3119
3120void ASTContext::setCFConstantStringType(QualType T) {
3121  const RecordType *Rec = T->getAs<RecordType>();
3122  assert(Rec && "Invalid CFConstantStringType");
3123  CFConstantStringTypeDecl = Rec->getDecl();
3124}
3125
3126// getNSConstantStringType - Return the type used for constant NSStrings.
3127QualType ASTContext::getNSConstantStringType() {
3128  if (!NSConstantStringTypeDecl) {
3129    NSConstantStringTypeDecl =
3130    CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3131                     &Idents.get("__builtin_NSString"));
3132    NSConstantStringTypeDecl->startDefinition();
3133
3134    QualType FieldTypes[3];
3135
3136    // const int *isa;
3137    FieldTypes[0] = getPointerType(IntTy.withConst());
3138    // const char *str;
3139    FieldTypes[1] = getPointerType(CharTy.withConst());
3140    // unsigned int length;
3141    FieldTypes[2] = UnsignedIntTy;
3142
3143    // Create fields
3144    for (unsigned i = 0; i < 3; ++i) {
3145      FieldDecl *Field = FieldDecl::Create(*this, NSConstantStringTypeDecl,
3146                                           SourceLocation(), 0,
3147                                           FieldTypes[i], /*TInfo=*/0,
3148                                           /*BitWidth=*/0,
3149                                           /*Mutable=*/false);
3150      Field->setAccess(AS_public);
3151      NSConstantStringTypeDecl->addDecl(Field);
3152    }
3153
3154    NSConstantStringTypeDecl->completeDefinition();
3155  }
3156
3157  return getTagDeclType(NSConstantStringTypeDecl);
3158}
3159
3160void ASTContext::setNSConstantStringType(QualType T) {
3161  const RecordType *Rec = T->getAs<RecordType>();
3162  assert(Rec && "Invalid NSConstantStringType");
3163  NSConstantStringTypeDecl = Rec->getDecl();
3164}
3165
3166QualType ASTContext::getObjCFastEnumerationStateType() {
3167  if (!ObjCFastEnumerationStateTypeDecl) {
3168    ObjCFastEnumerationStateTypeDecl =
3169      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3170                       &Idents.get("__objcFastEnumerationState"));
3171    ObjCFastEnumerationStateTypeDecl->startDefinition();
3172
3173    QualType FieldTypes[] = {
3174      UnsignedLongTy,
3175      getPointerType(ObjCIdTypedefType),
3176      getPointerType(UnsignedLongTy),
3177      getConstantArrayType(UnsignedLongTy,
3178                           llvm::APInt(32, 5), ArrayType::Normal, 0)
3179    };
3180
3181    for (size_t i = 0; i < 4; ++i) {
3182      FieldDecl *Field = FieldDecl::Create(*this,
3183                                           ObjCFastEnumerationStateTypeDecl,
3184                                           SourceLocation(), 0,
3185                                           FieldTypes[i], /*TInfo=*/0,
3186                                           /*BitWidth=*/0,
3187                                           /*Mutable=*/false);
3188      Field->setAccess(AS_public);
3189      ObjCFastEnumerationStateTypeDecl->addDecl(Field);
3190    }
3191
3192    ObjCFastEnumerationStateTypeDecl->completeDefinition();
3193  }
3194
3195  return getTagDeclType(ObjCFastEnumerationStateTypeDecl);
3196}
3197
3198QualType ASTContext::getBlockDescriptorType() {
3199  if (BlockDescriptorType)
3200    return getTagDeclType(BlockDescriptorType);
3201
3202  RecordDecl *T;
3203  // FIXME: Needs the FlagAppleBlock bit.
3204  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3205                       &Idents.get("__block_descriptor"));
3206  T->startDefinition();
3207
3208  QualType FieldTypes[] = {
3209    UnsignedLongTy,
3210    UnsignedLongTy,
3211  };
3212
3213  const char *FieldNames[] = {
3214    "reserved",
3215    "Size"
3216  };
3217
3218  for (size_t i = 0; i < 2; ++i) {
3219    FieldDecl *Field = FieldDecl::Create(*this,
3220                                         T,
3221                                         SourceLocation(),
3222                                         &Idents.get(FieldNames[i]),
3223                                         FieldTypes[i], /*TInfo=*/0,
3224                                         /*BitWidth=*/0,
3225                                         /*Mutable=*/false);
3226    Field->setAccess(AS_public);
3227    T->addDecl(Field);
3228  }
3229
3230  T->completeDefinition();
3231
3232  BlockDescriptorType = T;
3233
3234  return getTagDeclType(BlockDescriptorType);
3235}
3236
3237void ASTContext::setBlockDescriptorType(QualType T) {
3238  const RecordType *Rec = T->getAs<RecordType>();
3239  assert(Rec && "Invalid BlockDescriptorType");
3240  BlockDescriptorType = Rec->getDecl();
3241}
3242
3243QualType ASTContext::getBlockDescriptorExtendedType() {
3244  if (BlockDescriptorExtendedType)
3245    return getTagDeclType(BlockDescriptorExtendedType);
3246
3247  RecordDecl *T;
3248  // FIXME: Needs the FlagAppleBlock bit.
3249  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3250                       &Idents.get("__block_descriptor_withcopydispose"));
3251  T->startDefinition();
3252
3253  QualType FieldTypes[] = {
3254    UnsignedLongTy,
3255    UnsignedLongTy,
3256    getPointerType(VoidPtrTy),
3257    getPointerType(VoidPtrTy)
3258  };
3259
3260  const char *FieldNames[] = {
3261    "reserved",
3262    "Size",
3263    "CopyFuncPtr",
3264    "DestroyFuncPtr"
3265  };
3266
3267  for (size_t i = 0; i < 4; ++i) {
3268    FieldDecl *Field = FieldDecl::Create(*this,
3269                                         T,
3270                                         SourceLocation(),
3271                                         &Idents.get(FieldNames[i]),
3272                                         FieldTypes[i], /*TInfo=*/0,
3273                                         /*BitWidth=*/0,
3274                                         /*Mutable=*/false);
3275    Field->setAccess(AS_public);
3276    T->addDecl(Field);
3277  }
3278
3279  T->completeDefinition();
3280
3281  BlockDescriptorExtendedType = T;
3282
3283  return getTagDeclType(BlockDescriptorExtendedType);
3284}
3285
3286void ASTContext::setBlockDescriptorExtendedType(QualType T) {
3287  const RecordType *Rec = T->getAs<RecordType>();
3288  assert(Rec && "Invalid BlockDescriptorType");
3289  BlockDescriptorExtendedType = Rec->getDecl();
3290}
3291
3292bool ASTContext::BlockRequiresCopying(QualType Ty) {
3293  if (Ty->isBlockPointerType())
3294    return true;
3295  if (isObjCNSObjectType(Ty))
3296    return true;
3297  if (Ty->isObjCObjectPointerType())
3298    return true;
3299  if (getLangOptions().CPlusPlus) {
3300    if (const RecordType *RT = Ty->getAs<RecordType>()) {
3301      CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
3302      return RD->hasConstCopyConstructor(*this);
3303
3304    }
3305  }
3306  return false;
3307}
3308
3309QualType ASTContext::BuildByRefType(llvm::StringRef DeclName, QualType Ty) {
3310  //  type = struct __Block_byref_1_X {
3311  //    void *__isa;
3312  //    struct __Block_byref_1_X *__forwarding;
3313  //    unsigned int __flags;
3314  //    unsigned int __size;
3315  //    void *__copy_helper;            // as needed
3316  //    void *__destroy_help            // as needed
3317  //    int X;
3318  //  } *
3319
3320  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3321
3322  // FIXME: Move up
3323  llvm::SmallString<36> Name;
3324  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3325                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3326  RecordDecl *T;
3327  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3328                       &Idents.get(Name.str()));
3329  T->startDefinition();
3330  QualType Int32Ty = IntTy;
3331  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3332  QualType FieldTypes[] = {
3333    getPointerType(VoidPtrTy),
3334    getPointerType(getTagDeclType(T)),
3335    Int32Ty,
3336    Int32Ty,
3337    getPointerType(VoidPtrTy),
3338    getPointerType(VoidPtrTy),
3339    Ty
3340  };
3341
3342  llvm::StringRef FieldNames[] = {
3343    "__isa",
3344    "__forwarding",
3345    "__flags",
3346    "__size",
3347    "__copy_helper",
3348    "__destroy_helper",
3349    DeclName,
3350  };
3351
3352  for (size_t i = 0; i < 7; ++i) {
3353    if (!HasCopyAndDispose && i >=4 && i <= 5)
3354      continue;
3355    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3356                                         &Idents.get(FieldNames[i]),
3357                                         FieldTypes[i], /*TInfo=*/0,
3358                                         /*BitWidth=*/0, /*Mutable=*/false);
3359    Field->setAccess(AS_public);
3360    T->addDecl(Field);
3361  }
3362
3363  T->completeDefinition();
3364
3365  return getPointerType(getTagDeclType(T));
3366}
3367
3368
3369QualType ASTContext::getBlockParmType(
3370  bool BlockHasCopyDispose,
3371  llvm::SmallVectorImpl<const Expr *> &Layout) {
3372
3373  // FIXME: Move up
3374  llvm::SmallString<36> Name;
3375  llvm::raw_svector_ostream(Name) << "__block_literal_"
3376                                  << ++UniqueBlockParmTypeID;
3377  RecordDecl *T;
3378  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3379                       &Idents.get(Name.str()));
3380  T->startDefinition();
3381  QualType FieldTypes[] = {
3382    getPointerType(VoidPtrTy),
3383    IntTy,
3384    IntTy,
3385    getPointerType(VoidPtrTy),
3386    (BlockHasCopyDispose ?
3387     getPointerType(getBlockDescriptorExtendedType()) :
3388     getPointerType(getBlockDescriptorType()))
3389  };
3390
3391  const char *FieldNames[] = {
3392    "__isa",
3393    "__flags",
3394    "__reserved",
3395    "__FuncPtr",
3396    "__descriptor"
3397  };
3398
3399  for (size_t i = 0; i < 5; ++i) {
3400    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3401                                         &Idents.get(FieldNames[i]),
3402                                         FieldTypes[i], /*TInfo=*/0,
3403                                         /*BitWidth=*/0, /*Mutable=*/false);
3404    Field->setAccess(AS_public);
3405    T->addDecl(Field);
3406  }
3407
3408  for (unsigned i = 0; i < Layout.size(); ++i) {
3409    const Expr *E = Layout[i];
3410
3411    QualType FieldType = E->getType();
3412    IdentifierInfo *FieldName = 0;
3413    if (isa<CXXThisExpr>(E)) {
3414      FieldName = &Idents.get("this");
3415    } else if (const BlockDeclRefExpr *BDRE = dyn_cast<BlockDeclRefExpr>(E)) {
3416      const ValueDecl *D = BDRE->getDecl();
3417      FieldName = D->getIdentifier();
3418      if (BDRE->isByRef())
3419        FieldType = BuildByRefType(D->getName(), FieldType);
3420    } else {
3421      // Padding.
3422      assert(isa<ConstantArrayType>(FieldType) &&
3423             isa<DeclRefExpr>(E) &&
3424             !cast<DeclRefExpr>(E)->getDecl()->getDeclName() &&
3425             "doesn't match characteristics of padding decl");
3426    }
3427
3428    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3429                                         FieldName, FieldType, /*TInfo=*/0,
3430                                         /*BitWidth=*/0, /*Mutable=*/false);
3431    Field->setAccess(AS_public);
3432    T->addDecl(Field);
3433  }
3434
3435  T->completeDefinition();
3436
3437  return getPointerType(getTagDeclType(T));
3438}
3439
3440void ASTContext::setObjCFastEnumerationStateType(QualType T) {
3441  const RecordType *Rec = T->getAs<RecordType>();
3442  assert(Rec && "Invalid ObjCFAstEnumerationStateType");
3443  ObjCFastEnumerationStateTypeDecl = Rec->getDecl();
3444}
3445
3446// This returns true if a type has been typedefed to BOOL:
3447// typedef <type> BOOL;
3448static bool isTypeTypedefedAsBOOL(QualType T) {
3449  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3450    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3451      return II->isStr("BOOL");
3452
3453  return false;
3454}
3455
3456/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3457/// purpose.
3458CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) {
3459  CharUnits sz = getTypeSizeInChars(type);
3460
3461  // Make all integer and enum types at least as large as an int
3462  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3463    sz = std::max(sz, getTypeSizeInChars(IntTy));
3464  // Treat arrays as pointers, since that's how they're passed in.
3465  else if (type->isArrayType())
3466    sz = getTypeSizeInChars(VoidPtrTy);
3467  return sz;
3468}
3469
3470static inline
3471std::string charUnitsToString(const CharUnits &CU) {
3472  return llvm::itostr(CU.getQuantity());
3473}
3474
3475/// getObjCEncodingForBlockDecl - Return the encoded type for this block
3476/// declaration.
3477void ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr,
3478                                             std::string& S) {
3479  const BlockDecl *Decl = Expr->getBlockDecl();
3480  QualType BlockTy =
3481      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3482  // Encode result type.
3483  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3484  // Compute size of all parameters.
3485  // Start with computing size of a pointer in number of bytes.
3486  // FIXME: There might(should) be a better way of doing this computation!
3487  SourceLocation Loc;
3488  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3489  CharUnits ParmOffset = PtrSize;
3490  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3491       E = Decl->param_end(); PI != E; ++PI) {
3492    QualType PType = (*PI)->getType();
3493    CharUnits sz = getObjCEncodingTypeSize(PType);
3494    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3495    ParmOffset += sz;
3496  }
3497  // Size of the argument frame
3498  S += charUnitsToString(ParmOffset);
3499  // Block pointer and offset.
3500  S += "@?0";
3501  ParmOffset = PtrSize;
3502
3503  // Argument types.
3504  ParmOffset = PtrSize;
3505  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3506       Decl->param_end(); PI != E; ++PI) {
3507    ParmVarDecl *PVDecl = *PI;
3508    QualType PType = PVDecl->getOriginalType();
3509    if (const ArrayType *AT =
3510          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3511      // Use array's original type only if it has known number of
3512      // elements.
3513      if (!isa<ConstantArrayType>(AT))
3514        PType = PVDecl->getType();
3515    } else if (PType->isFunctionType())
3516      PType = PVDecl->getType();
3517    getObjCEncodingForType(PType, S);
3518    S += charUnitsToString(ParmOffset);
3519    ParmOffset += getObjCEncodingTypeSize(PType);
3520  }
3521}
3522
3523/// getObjCEncodingForMethodDecl - Return the encoded type for this method
3524/// declaration.
3525void ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
3526                                              std::string& S) {
3527  // FIXME: This is not very efficient.
3528  // Encode type qualifer, 'in', 'inout', etc. for the return type.
3529  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
3530  // Encode result type.
3531  getObjCEncodingForType(Decl->getResultType(), S);
3532  // Compute size of all parameters.
3533  // Start with computing size of a pointer in number of bytes.
3534  // FIXME: There might(should) be a better way of doing this computation!
3535  SourceLocation Loc;
3536  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3537  // The first two arguments (self and _cmd) are pointers; account for
3538  // their size.
3539  CharUnits ParmOffset = 2 * PtrSize;
3540  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3541       E = Decl->sel_param_end(); PI != E; ++PI) {
3542    QualType PType = (*PI)->getType();
3543    CharUnits sz = getObjCEncodingTypeSize(PType);
3544    assert (sz.isPositive() &&
3545        "getObjCEncodingForMethodDecl - Incomplete param type");
3546    ParmOffset += sz;
3547  }
3548  S += charUnitsToString(ParmOffset);
3549  S += "@0:";
3550  S += charUnitsToString(PtrSize);
3551
3552  // Argument types.
3553  ParmOffset = 2 * PtrSize;
3554  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3555       E = Decl->sel_param_end(); PI != E; ++PI) {
3556    ParmVarDecl *PVDecl = *PI;
3557    QualType PType = PVDecl->getOriginalType();
3558    if (const ArrayType *AT =
3559          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3560      // Use array's original type only if it has known number of
3561      // elements.
3562      if (!isa<ConstantArrayType>(AT))
3563        PType = PVDecl->getType();
3564    } else if (PType->isFunctionType())
3565      PType = PVDecl->getType();
3566    // Process argument qualifiers for user supplied arguments; such as,
3567    // 'in', 'inout', etc.
3568    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
3569    getObjCEncodingForType(PType, S);
3570    S += charUnitsToString(ParmOffset);
3571    ParmOffset += getObjCEncodingTypeSize(PType);
3572  }
3573}
3574
3575/// getObjCEncodingForPropertyDecl - Return the encoded type for this
3576/// property declaration. If non-NULL, Container must be either an
3577/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
3578/// NULL when getting encodings for protocol properties.
3579/// Property attributes are stored as a comma-delimited C string. The simple
3580/// attributes readonly and bycopy are encoded as single characters. The
3581/// parametrized attributes, getter=name, setter=name, and ivar=name, are
3582/// encoded as single characters, followed by an identifier. Property types
3583/// are also encoded as a parametrized attribute. The characters used to encode
3584/// these attributes are defined by the following enumeration:
3585/// @code
3586/// enum PropertyAttributes {
3587/// kPropertyReadOnly = 'R',   // property is read-only.
3588/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
3589/// kPropertyByref = '&',  // property is a reference to the value last assigned
3590/// kPropertyDynamic = 'D',    // property is dynamic
3591/// kPropertyGetter = 'G',     // followed by getter selector name
3592/// kPropertySetter = 'S',     // followed by setter selector name
3593/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
3594/// kPropertyType = 't'              // followed by old-style type encoding.
3595/// kPropertyWeak = 'W'              // 'weak' property
3596/// kPropertyStrong = 'P'            // property GC'able
3597/// kPropertyNonAtomic = 'N'         // property non-atomic
3598/// };
3599/// @endcode
3600void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
3601                                                const Decl *Container,
3602                                                std::string& S) {
3603  // Collect information from the property implementation decl(s).
3604  bool Dynamic = false;
3605  ObjCPropertyImplDecl *SynthesizePID = 0;
3606
3607  // FIXME: Duplicated code due to poor abstraction.
3608  if (Container) {
3609    if (const ObjCCategoryImplDecl *CID =
3610        dyn_cast<ObjCCategoryImplDecl>(Container)) {
3611      for (ObjCCategoryImplDecl::propimpl_iterator
3612             i = CID->propimpl_begin(), e = CID->propimpl_end();
3613           i != e; ++i) {
3614        ObjCPropertyImplDecl *PID = *i;
3615        if (PID->getPropertyDecl() == PD) {
3616          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3617            Dynamic = true;
3618          } else {
3619            SynthesizePID = PID;
3620          }
3621        }
3622      }
3623    } else {
3624      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
3625      for (ObjCCategoryImplDecl::propimpl_iterator
3626             i = OID->propimpl_begin(), e = OID->propimpl_end();
3627           i != e; ++i) {
3628        ObjCPropertyImplDecl *PID = *i;
3629        if (PID->getPropertyDecl() == PD) {
3630          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3631            Dynamic = true;
3632          } else {
3633            SynthesizePID = PID;
3634          }
3635        }
3636      }
3637    }
3638  }
3639
3640  // FIXME: This is not very efficient.
3641  S = "T";
3642
3643  // Encode result type.
3644  // GCC has some special rules regarding encoding of properties which
3645  // closely resembles encoding of ivars.
3646  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
3647                             true /* outermost type */,
3648                             true /* encoding for property */);
3649
3650  if (PD->isReadOnly()) {
3651    S += ",R";
3652  } else {
3653    switch (PD->getSetterKind()) {
3654    case ObjCPropertyDecl::Assign: break;
3655    case ObjCPropertyDecl::Copy:   S += ",C"; break;
3656    case ObjCPropertyDecl::Retain: S += ",&"; break;
3657    }
3658  }
3659
3660  // It really isn't clear at all what this means, since properties
3661  // are "dynamic by default".
3662  if (Dynamic)
3663    S += ",D";
3664
3665  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
3666    S += ",N";
3667
3668  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
3669    S += ",G";
3670    S += PD->getGetterName().getAsString();
3671  }
3672
3673  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
3674    S += ",S";
3675    S += PD->getSetterName().getAsString();
3676  }
3677
3678  if (SynthesizePID) {
3679    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
3680    S += ",V";
3681    S += OID->getNameAsString();
3682  }
3683
3684  // FIXME: OBJCGC: weak & strong
3685}
3686
3687/// getLegacyIntegralTypeEncoding -
3688/// Another legacy compatibility encoding: 32-bit longs are encoded as
3689/// 'l' or 'L' , but not always.  For typedefs, we need to use
3690/// 'i' or 'I' instead if encoding a struct field, or a pointer!
3691///
3692void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
3693  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
3694    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
3695      if (BT->getKind() == BuiltinType::ULong &&
3696          ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3697        PointeeTy = UnsignedIntTy;
3698      else
3699        if (BT->getKind() == BuiltinType::Long &&
3700            ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3701          PointeeTy = IntTy;
3702    }
3703  }
3704}
3705
3706void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
3707                                        const FieldDecl *Field) {
3708  // We follow the behavior of gcc, expanding structures which are
3709  // directly pointed to, and expanding embedded structures. Note that
3710  // these rules are sufficient to prevent recursive encoding of the
3711  // same type.
3712  getObjCEncodingForTypeImpl(T, S, true, true, Field,
3713                             true /* outermost type */);
3714}
3715
3716static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
3717    switch (T->getAs<BuiltinType>()->getKind()) {
3718    default: assert(0 && "Unhandled builtin type kind");
3719    case BuiltinType::Void:       return 'v';
3720    case BuiltinType::Bool:       return 'B';
3721    case BuiltinType::Char_U:
3722    case BuiltinType::UChar:      return 'C';
3723    case BuiltinType::UShort:     return 'S';
3724    case BuiltinType::UInt:       return 'I';
3725    case BuiltinType::ULong:
3726        return
3727          (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'L' : 'Q';
3728    case BuiltinType::UInt128:    return 'T';
3729    case BuiltinType::ULongLong:  return 'Q';
3730    case BuiltinType::Char_S:
3731    case BuiltinType::SChar:      return 'c';
3732    case BuiltinType::Short:      return 's';
3733    case BuiltinType::WChar:
3734    case BuiltinType::Int:        return 'i';
3735    case BuiltinType::Long:
3736      return
3737        (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'l' : 'q';
3738    case BuiltinType::LongLong:   return 'q';
3739    case BuiltinType::Int128:     return 't';
3740    case BuiltinType::Float:      return 'f';
3741    case BuiltinType::Double:     return 'd';
3742    case BuiltinType::LongDouble: return 'D';
3743    }
3744}
3745
3746static void EncodeBitField(const ASTContext *Context, std::string& S,
3747                           QualType T, const FieldDecl *FD) {
3748  const Expr *E = FD->getBitWidth();
3749  assert(E && "bitfield width not there - getObjCEncodingForTypeImpl");
3750  ASTContext *Ctx = const_cast<ASTContext*>(Context);
3751  S += 'b';
3752  // The NeXT runtime encodes bit fields as b followed by the number of bits.
3753  // The GNU runtime requires more information; bitfields are encoded as b,
3754  // then the offset (in bits) of the first element, then the type of the
3755  // bitfield, then the size in bits.  For example, in this structure:
3756  //
3757  // struct
3758  // {
3759  //    int integer;
3760  //    int flags:2;
3761  // };
3762  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
3763  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
3764  // information is not especially sensible, but we're stuck with it for
3765  // compatibility with GCC, although providing it breaks anything that
3766  // actually uses runtime introspection and wants to work on both runtimes...
3767  if (!Ctx->getLangOptions().NeXTRuntime) {
3768    const RecordDecl *RD = FD->getParent();
3769    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
3770    // FIXME: This same linear search is also used in ExprConstant - it might
3771    // be better if the FieldDecl stored its offset.  We'd be increasing the
3772    // size of the object slightly, but saving some time every time it is used.
3773    unsigned i = 0;
3774    for (RecordDecl::field_iterator Field = RD->field_begin(),
3775                                 FieldEnd = RD->field_end();
3776         Field != FieldEnd; (void)++Field, ++i) {
3777      if (*Field == FD)
3778        break;
3779    }
3780    S += llvm::utostr(RL.getFieldOffset(i));
3781    S += ObjCEncodingForPrimitiveKind(Context, T);
3782  }
3783  unsigned N = E->EvaluateAsInt(*Ctx).getZExtValue();
3784  S += llvm::utostr(N);
3785}
3786
3787// FIXME: Use SmallString for accumulating string.
3788void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
3789                                            bool ExpandPointedToStructures,
3790                                            bool ExpandStructures,
3791                                            const FieldDecl *FD,
3792                                            bool OutermostType,
3793                                            bool EncodingProperty) {
3794  if (T->getAs<BuiltinType>()) {
3795    if (FD && FD->isBitField())
3796      return EncodeBitField(this, S, T, FD);
3797    S += ObjCEncodingForPrimitiveKind(this, T);
3798    return;
3799  }
3800
3801  if (const ComplexType *CT = T->getAs<ComplexType>()) {
3802    S += 'j';
3803    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
3804                               false);
3805    return;
3806  }
3807
3808  // encoding for pointer or r3eference types.
3809  QualType PointeeTy;
3810  if (const PointerType *PT = T->getAs<PointerType>()) {
3811    if (PT->isObjCSelType()) {
3812      S += ':';
3813      return;
3814    }
3815    PointeeTy = PT->getPointeeType();
3816  }
3817  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3818    PointeeTy = RT->getPointeeType();
3819  if (!PointeeTy.isNull()) {
3820    bool isReadOnly = false;
3821    // For historical/compatibility reasons, the read-only qualifier of the
3822    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
3823    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
3824    // Also, do not emit the 'r' for anything but the outermost type!
3825    if (isa<TypedefType>(T.getTypePtr())) {
3826      if (OutermostType && T.isConstQualified()) {
3827        isReadOnly = true;
3828        S += 'r';
3829      }
3830    } else if (OutermostType) {
3831      QualType P = PointeeTy;
3832      while (P->getAs<PointerType>())
3833        P = P->getAs<PointerType>()->getPointeeType();
3834      if (P.isConstQualified()) {
3835        isReadOnly = true;
3836        S += 'r';
3837      }
3838    }
3839    if (isReadOnly) {
3840      // Another legacy compatibility encoding. Some ObjC qualifier and type
3841      // combinations need to be rearranged.
3842      // Rewrite "in const" from "nr" to "rn"
3843      if (llvm::StringRef(S).endswith("nr"))
3844        S.replace(S.end()-2, S.end(), "rn");
3845    }
3846
3847    if (PointeeTy->isCharType()) {
3848      // char pointer types should be encoded as '*' unless it is a
3849      // type that has been typedef'd to 'BOOL'.
3850      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
3851        S += '*';
3852        return;
3853      }
3854    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
3855      // GCC binary compat: Need to convert "struct objc_class *" to "#".
3856      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
3857        S += '#';
3858        return;
3859      }
3860      // GCC binary compat: Need to convert "struct objc_object *" to "@".
3861      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
3862        S += '@';
3863        return;
3864      }
3865      // fall through...
3866    }
3867    S += '^';
3868    getLegacyIntegralTypeEncoding(PointeeTy);
3869
3870    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
3871                               NULL);
3872    return;
3873  }
3874
3875  if (const ArrayType *AT =
3876      // Ignore type qualifiers etc.
3877        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
3878    if (isa<IncompleteArrayType>(AT)) {
3879      // Incomplete arrays are encoded as a pointer to the array element.
3880      S += '^';
3881
3882      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3883                                 false, ExpandStructures, FD);
3884    } else {
3885      S += '[';
3886
3887      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
3888        S += llvm::utostr(CAT->getSize().getZExtValue());
3889      else {
3890        //Variable length arrays are encoded as a regular array with 0 elements.
3891        assert(isa<VariableArrayType>(AT) && "Unknown array type!");
3892        S += '0';
3893      }
3894
3895      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3896                                 false, ExpandStructures, FD);
3897      S += ']';
3898    }
3899    return;
3900  }
3901
3902  if (T->getAs<FunctionType>()) {
3903    S += '?';
3904    return;
3905  }
3906
3907  if (const RecordType *RTy = T->getAs<RecordType>()) {
3908    RecordDecl *RDecl = RTy->getDecl();
3909    S += RDecl->isUnion() ? '(' : '{';
3910    // Anonymous structures print as '?'
3911    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
3912      S += II->getName();
3913      if (ClassTemplateSpecializationDecl *Spec
3914          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
3915        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
3916        std::string TemplateArgsStr
3917          = TemplateSpecializationType::PrintTemplateArgumentList(
3918                                            TemplateArgs.data(),
3919                                            TemplateArgs.size(),
3920                                            (*this).PrintingPolicy);
3921
3922        S += TemplateArgsStr;
3923      }
3924    } else {
3925      S += '?';
3926    }
3927    if (ExpandStructures) {
3928      S += '=';
3929      for (RecordDecl::field_iterator Field = RDecl->field_begin(),
3930                                   FieldEnd = RDecl->field_end();
3931           Field != FieldEnd; ++Field) {
3932        if (FD) {
3933          S += '"';
3934          S += Field->getNameAsString();
3935          S += '"';
3936        }
3937
3938        // Special case bit-fields.
3939        if (Field->isBitField()) {
3940          getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
3941                                     (*Field));
3942        } else {
3943          QualType qt = Field->getType();
3944          getLegacyIntegralTypeEncoding(qt);
3945          getObjCEncodingForTypeImpl(qt, S, false, true,
3946                                     FD);
3947        }
3948      }
3949    }
3950    S += RDecl->isUnion() ? ')' : '}';
3951    return;
3952  }
3953
3954  if (T->isEnumeralType()) {
3955    if (FD && FD->isBitField())
3956      EncodeBitField(this, S, T, FD);
3957    else
3958      S += 'i';
3959    return;
3960  }
3961
3962  if (T->isBlockPointerType()) {
3963    S += "@?"; // Unlike a pointer-to-function, which is "^?".
3964    return;
3965  }
3966
3967  // Ignore protocol qualifiers when mangling at this level.
3968  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
3969    T = OT->getBaseType();
3970
3971  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
3972    // @encode(class_name)
3973    ObjCInterfaceDecl *OI = OIT->getDecl();
3974    S += '{';
3975    const IdentifierInfo *II = OI->getIdentifier();
3976    S += II->getName();
3977    S += '=';
3978    llvm::SmallVector<ObjCIvarDecl*, 32> Ivars;
3979    DeepCollectObjCIvars(OI, true, Ivars);
3980    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
3981      FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
3982      if (Field->isBitField())
3983        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
3984      else
3985        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
3986    }
3987    S += '}';
3988    return;
3989  }
3990
3991  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
3992    if (OPT->isObjCIdType()) {
3993      S += '@';
3994      return;
3995    }
3996
3997    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
3998      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
3999      // Since this is a binary compatibility issue, need to consult with runtime
4000      // folks. Fortunately, this is a *very* obsure construct.
4001      S += '#';
4002      return;
4003    }
4004
4005    if (OPT->isObjCQualifiedIdType()) {
4006      getObjCEncodingForTypeImpl(getObjCIdType(), S,
4007                                 ExpandPointedToStructures,
4008                                 ExpandStructures, FD);
4009      if (FD || EncodingProperty) {
4010        // Note that we do extended encoding of protocol qualifer list
4011        // Only when doing ivar or property encoding.
4012        S += '"';
4013        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4014             E = OPT->qual_end(); I != E; ++I) {
4015          S += '<';
4016          S += (*I)->getNameAsString();
4017          S += '>';
4018        }
4019        S += '"';
4020      }
4021      return;
4022    }
4023
4024    QualType PointeeTy = OPT->getPointeeType();
4025    if (!EncodingProperty &&
4026        isa<TypedefType>(PointeeTy.getTypePtr())) {
4027      // Another historical/compatibility reason.
4028      // We encode the underlying type which comes out as
4029      // {...};
4030      S += '^';
4031      getObjCEncodingForTypeImpl(PointeeTy, S,
4032                                 false, ExpandPointedToStructures,
4033                                 NULL);
4034      return;
4035    }
4036
4037    S += '@';
4038    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
4039      S += '"';
4040      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4041      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4042           E = OPT->qual_end(); I != E; ++I) {
4043        S += '<';
4044        S += (*I)->getNameAsString();
4045        S += '>';
4046      }
4047      S += '"';
4048    }
4049    return;
4050  }
4051
4052  // gcc just blithely ignores member pointers.
4053  // TODO: maybe there should be a mangling for these
4054  if (T->getAs<MemberPointerType>())
4055    return;
4056
4057  if (T->isVectorType()) {
4058    // This matches gcc's encoding, even though technically it is
4059    // insufficient.
4060    // FIXME. We should do a better job than gcc.
4061    return;
4062  }
4063
4064  assert(0 && "@encode for type not implemented!");
4065}
4066
4067void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4068                                                 std::string& S) const {
4069  if (QT & Decl::OBJC_TQ_In)
4070    S += 'n';
4071  if (QT & Decl::OBJC_TQ_Inout)
4072    S += 'N';
4073  if (QT & Decl::OBJC_TQ_Out)
4074    S += 'o';
4075  if (QT & Decl::OBJC_TQ_Bycopy)
4076    S += 'O';
4077  if (QT & Decl::OBJC_TQ_Byref)
4078    S += 'R';
4079  if (QT & Decl::OBJC_TQ_Oneway)
4080    S += 'V';
4081}
4082
4083void ASTContext::setBuiltinVaListType(QualType T) {
4084  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4085
4086  BuiltinVaListType = T;
4087}
4088
4089void ASTContext::setObjCIdType(QualType T) {
4090  ObjCIdTypedefType = T;
4091}
4092
4093void ASTContext::setObjCSelType(QualType T) {
4094  ObjCSelTypedefType = T;
4095}
4096
4097void ASTContext::setObjCProtoType(QualType QT) {
4098  ObjCProtoType = QT;
4099}
4100
4101void ASTContext::setObjCClassType(QualType T) {
4102  ObjCClassTypedefType = T;
4103}
4104
4105void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4106  assert(ObjCConstantStringType.isNull() &&
4107         "'NSConstantString' type already set!");
4108
4109  ObjCConstantStringType = getObjCInterfaceType(Decl);
4110}
4111
4112/// \brief Retrieve the template name that corresponds to a non-empty
4113/// lookup.
4114TemplateName ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4115                                                   UnresolvedSetIterator End) {
4116  unsigned size = End - Begin;
4117  assert(size > 1 && "set is not overloaded!");
4118
4119  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4120                          size * sizeof(FunctionTemplateDecl*));
4121  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4122
4123  NamedDecl **Storage = OT->getStorage();
4124  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4125    NamedDecl *D = *I;
4126    assert(isa<FunctionTemplateDecl>(D) ||
4127           (isa<UsingShadowDecl>(D) &&
4128            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4129    *Storage++ = D;
4130  }
4131
4132  return TemplateName(OT);
4133}
4134
4135/// \brief Retrieve the template name that represents a qualified
4136/// template name such as \c std::vector.
4137TemplateName ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4138                                                  bool TemplateKeyword,
4139                                                  TemplateDecl *Template) {
4140  // FIXME: Canonicalization?
4141  llvm::FoldingSetNodeID ID;
4142  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4143
4144  void *InsertPos = 0;
4145  QualifiedTemplateName *QTN =
4146    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4147  if (!QTN) {
4148    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4149    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4150  }
4151
4152  return TemplateName(QTN);
4153}
4154
4155/// \brief Retrieve the template name that represents a dependent
4156/// template name such as \c MetaFun::template apply.
4157TemplateName ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4158                                                  const IdentifierInfo *Name) {
4159  assert((!NNS || NNS->isDependent()) &&
4160         "Nested name specifier must be dependent");
4161
4162  llvm::FoldingSetNodeID ID;
4163  DependentTemplateName::Profile(ID, NNS, Name);
4164
4165  void *InsertPos = 0;
4166  DependentTemplateName *QTN =
4167    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4168
4169  if (QTN)
4170    return TemplateName(QTN);
4171
4172  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4173  if (CanonNNS == NNS) {
4174    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4175  } else {
4176    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4177    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4178    DependentTemplateName *CheckQTN =
4179      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4180    assert(!CheckQTN && "Dependent type name canonicalization broken");
4181    (void)CheckQTN;
4182  }
4183
4184  DependentTemplateNames.InsertNode(QTN, InsertPos);
4185  return TemplateName(QTN);
4186}
4187
4188/// \brief Retrieve the template name that represents a dependent
4189/// template name such as \c MetaFun::template operator+.
4190TemplateName
4191ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4192                                     OverloadedOperatorKind Operator) {
4193  assert((!NNS || NNS->isDependent()) &&
4194         "Nested name specifier must be dependent");
4195
4196  llvm::FoldingSetNodeID ID;
4197  DependentTemplateName::Profile(ID, NNS, Operator);
4198
4199  void *InsertPos = 0;
4200  DependentTemplateName *QTN
4201    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4202
4203  if (QTN)
4204    return TemplateName(QTN);
4205
4206  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4207  if (CanonNNS == NNS) {
4208    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4209  } else {
4210    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4211    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4212
4213    DependentTemplateName *CheckQTN
4214      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4215    assert(!CheckQTN && "Dependent template name canonicalization broken");
4216    (void)CheckQTN;
4217  }
4218
4219  DependentTemplateNames.InsertNode(QTN, InsertPos);
4220  return TemplateName(QTN);
4221}
4222
4223/// getFromTargetType - Given one of the integer types provided by
4224/// TargetInfo, produce the corresponding type. The unsigned @p Type
4225/// is actually a value of type @c TargetInfo::IntType.
4226CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4227  switch (Type) {
4228  case TargetInfo::NoInt: return CanQualType();
4229  case TargetInfo::SignedShort: return ShortTy;
4230  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4231  case TargetInfo::SignedInt: return IntTy;
4232  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4233  case TargetInfo::SignedLong: return LongTy;
4234  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4235  case TargetInfo::SignedLongLong: return LongLongTy;
4236  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4237  }
4238
4239  assert(false && "Unhandled TargetInfo::IntType value");
4240  return CanQualType();
4241}
4242
4243//===----------------------------------------------------------------------===//
4244//                        Type Predicates.
4245//===----------------------------------------------------------------------===//
4246
4247/// isObjCNSObjectType - Return true if this is an NSObject object using
4248/// NSObject attribute on a c-style pointer type.
4249/// FIXME - Make it work directly on types.
4250/// FIXME: Move to Type.
4251///
4252bool ASTContext::isObjCNSObjectType(QualType Ty) const {
4253  if (TypedefType *TDT = dyn_cast<TypedefType>(Ty)) {
4254    if (TypedefDecl *TD = TDT->getDecl())
4255      if (TD->getAttr<ObjCNSObjectAttr>())
4256        return true;
4257  }
4258  return false;
4259}
4260
4261/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4262/// garbage collection attribute.
4263///
4264Qualifiers::GC ASTContext::getObjCGCAttrKind(const QualType &Ty) const {
4265  Qualifiers::GC GCAttrs = Qualifiers::GCNone;
4266  if (getLangOptions().ObjC1 &&
4267      getLangOptions().getGCMode() != LangOptions::NonGC) {
4268    GCAttrs = Ty.getObjCGCAttr();
4269    // Default behavious under objective-c's gc is for objective-c pointers
4270    // (or pointers to them) be treated as though they were declared
4271    // as __strong.
4272    if (GCAttrs == Qualifiers::GCNone) {
4273      if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4274        GCAttrs = Qualifiers::Strong;
4275      else if (Ty->isPointerType())
4276        return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4277    }
4278    // Non-pointers have none gc'able attribute regardless of the attribute
4279    // set on them.
4280    else if (!Ty->isAnyPointerType() && !Ty->isBlockPointerType())
4281      return Qualifiers::GCNone;
4282  }
4283  return GCAttrs;
4284}
4285
4286//===----------------------------------------------------------------------===//
4287//                        Type Compatibility Testing
4288//===----------------------------------------------------------------------===//
4289
4290/// areCompatVectorTypes - Return true if the two specified vector types are
4291/// compatible.
4292static bool areCompatVectorTypes(const VectorType *LHS,
4293                                 const VectorType *RHS) {
4294  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
4295  return LHS->getElementType() == RHS->getElementType() &&
4296         LHS->getNumElements() == RHS->getNumElements();
4297}
4298
4299bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
4300                                          QualType SecondVec) {
4301  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
4302  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
4303
4304  if (hasSameUnqualifiedType(FirstVec, SecondVec))
4305    return true;
4306
4307  // Treat Neon vector types and most AltiVec vector types as if they are the
4308  // equivalent GCC vector types.
4309  const VectorType *First = FirstVec->getAs<VectorType>();
4310  const VectorType *Second = SecondVec->getAs<VectorType>();
4311  if (First->getNumElements() == Second->getNumElements() &&
4312      hasSameType(First->getElementType(), Second->getElementType()) &&
4313      First->getVectorKind() != VectorType::AltiVecPixel &&
4314      First->getVectorKind() != VectorType::AltiVecBool &&
4315      Second->getVectorKind() != VectorType::AltiVecPixel &&
4316      Second->getVectorKind() != VectorType::AltiVecBool)
4317    return true;
4318
4319  return false;
4320}
4321
4322//===----------------------------------------------------------------------===//
4323// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
4324//===----------------------------------------------------------------------===//
4325
4326/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
4327/// inheritance hierarchy of 'rProto'.
4328bool ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
4329                                                ObjCProtocolDecl *rProto) {
4330  if (lProto == rProto)
4331    return true;
4332  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
4333       E = rProto->protocol_end(); PI != E; ++PI)
4334    if (ProtocolCompatibleWithProtocol(lProto, *PI))
4335      return true;
4336  return false;
4337}
4338
4339/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
4340/// return true if lhs's protocols conform to rhs's protocol; false
4341/// otherwise.
4342bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
4343  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
4344    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
4345  return false;
4346}
4347
4348/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
4349/// Class<p1, ...>.
4350bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
4351                                                      QualType rhs) {
4352  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
4353  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4354  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
4355
4356  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4357       E = lhsQID->qual_end(); I != E; ++I) {
4358    bool match = false;
4359    ObjCProtocolDecl *lhsProto = *I;
4360    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4361         E = rhsOPT->qual_end(); J != E; ++J) {
4362      ObjCProtocolDecl *rhsProto = *J;
4363      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
4364        match = true;
4365        break;
4366      }
4367    }
4368    if (!match)
4369      return false;
4370  }
4371  return true;
4372}
4373
4374/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
4375/// ObjCQualifiedIDType.
4376bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
4377                                                   bool compare) {
4378  // Allow id<P..> and an 'id' or void* type in all cases.
4379  if (lhs->isVoidPointerType() ||
4380      lhs->isObjCIdType() || lhs->isObjCClassType())
4381    return true;
4382  else if (rhs->isVoidPointerType() ||
4383           rhs->isObjCIdType() || rhs->isObjCClassType())
4384    return true;
4385
4386  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
4387    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4388
4389    if (!rhsOPT) return false;
4390
4391    if (rhsOPT->qual_empty()) {
4392      // If the RHS is a unqualified interface pointer "NSString*",
4393      // make sure we check the class hierarchy.
4394      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4395        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4396             E = lhsQID->qual_end(); I != E; ++I) {
4397          // when comparing an id<P> on lhs with a static type on rhs,
4398          // see if static class implements all of id's protocols, directly or
4399          // through its super class and categories.
4400          if (!rhsID->ClassImplementsProtocol(*I, true))
4401            return false;
4402        }
4403      }
4404      // If there are no qualifiers and no interface, we have an 'id'.
4405      return true;
4406    }
4407    // Both the right and left sides have qualifiers.
4408    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4409         E = lhsQID->qual_end(); I != E; ++I) {
4410      ObjCProtocolDecl *lhsProto = *I;
4411      bool match = false;
4412
4413      // when comparing an id<P> on lhs with a static type on rhs,
4414      // see if static class implements all of id's protocols, directly or
4415      // through its super class and categories.
4416      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4417           E = rhsOPT->qual_end(); J != E; ++J) {
4418        ObjCProtocolDecl *rhsProto = *J;
4419        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4420            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4421          match = true;
4422          break;
4423        }
4424      }
4425      // If the RHS is a qualified interface pointer "NSString<P>*",
4426      // make sure we check the class hierarchy.
4427      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4428        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4429             E = lhsQID->qual_end(); I != E; ++I) {
4430          // when comparing an id<P> on lhs with a static type on rhs,
4431          // see if static class implements all of id's protocols, directly or
4432          // through its super class and categories.
4433          if (rhsID->ClassImplementsProtocol(*I, true)) {
4434            match = true;
4435            break;
4436          }
4437        }
4438      }
4439      if (!match)
4440        return false;
4441    }
4442
4443    return true;
4444  }
4445
4446  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
4447  assert(rhsQID && "One of the LHS/RHS should be id<x>");
4448
4449  if (const ObjCObjectPointerType *lhsOPT =
4450        lhs->getAsObjCInterfacePointerType()) {
4451    // If both the right and left sides have qualifiers.
4452    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
4453         E = lhsOPT->qual_end(); I != E; ++I) {
4454      ObjCProtocolDecl *lhsProto = *I;
4455      bool match = false;
4456
4457      // when comparing an id<P> on rhs with a static type on lhs,
4458      // see if static class implements all of id's protocols, directly or
4459      // through its super class and categories.
4460      // First, lhs protocols in the qualifier list must be found, direct
4461      // or indirect in rhs's qualifier list or it is a mismatch.
4462      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4463           E = rhsQID->qual_end(); J != E; ++J) {
4464        ObjCProtocolDecl *rhsProto = *J;
4465        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4466            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4467          match = true;
4468          break;
4469        }
4470      }
4471      if (!match)
4472        return false;
4473    }
4474
4475    // Static class's protocols, or its super class or category protocols
4476    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
4477    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
4478      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4479      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
4480      // This is rather dubious but matches gcc's behavior. If lhs has
4481      // no type qualifier and its class has no static protocol(s)
4482      // assume that it is mismatch.
4483      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
4484        return false;
4485      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4486           LHSInheritedProtocols.begin(),
4487           E = LHSInheritedProtocols.end(); I != E; ++I) {
4488        bool match = false;
4489        ObjCProtocolDecl *lhsProto = (*I);
4490        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4491             E = rhsQID->qual_end(); J != E; ++J) {
4492          ObjCProtocolDecl *rhsProto = *J;
4493          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4494              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4495            match = true;
4496            break;
4497          }
4498        }
4499        if (!match)
4500          return false;
4501      }
4502    }
4503    return true;
4504  }
4505  return false;
4506}
4507
4508/// canAssignObjCInterfaces - Return true if the two interface types are
4509/// compatible for assignment from RHS to LHS.  This handles validation of any
4510/// protocol qualifiers on the LHS or RHS.
4511///
4512bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
4513                                         const ObjCObjectPointerType *RHSOPT) {
4514  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4515  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4516
4517  // If either type represents the built-in 'id' or 'Class' types, return true.
4518  if (LHS->isObjCUnqualifiedIdOrClass() ||
4519      RHS->isObjCUnqualifiedIdOrClass())
4520    return true;
4521
4522  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
4523    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4524                                             QualType(RHSOPT,0),
4525                                             false);
4526
4527  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
4528    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
4529                                                QualType(RHSOPT,0));
4530
4531  // If we have 2 user-defined types, fall into that path.
4532  if (LHS->getInterface() && RHS->getInterface())
4533    return canAssignObjCInterfaces(LHS, RHS);
4534
4535  return false;
4536}
4537
4538/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
4539/// for providing type-safty for objective-c pointers used to pass/return
4540/// arguments in block literals. When passed as arguments, passing 'A*' where
4541/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
4542/// not OK. For the return type, the opposite is not OK.
4543bool ASTContext::canAssignObjCInterfacesInBlockPointer(
4544                                         const ObjCObjectPointerType *LHSOPT,
4545                                         const ObjCObjectPointerType *RHSOPT) {
4546  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
4547    return true;
4548
4549  if (LHSOPT->isObjCBuiltinType()) {
4550    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
4551  }
4552
4553  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
4554    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4555                                             QualType(RHSOPT,0),
4556                                             false);
4557
4558  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
4559  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
4560  if (LHS && RHS)  { // We have 2 user-defined types.
4561    if (LHS != RHS) {
4562      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
4563        return false;
4564      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
4565        return true;
4566    }
4567    else
4568      return true;
4569  }
4570  return false;
4571}
4572
4573/// getIntersectionOfProtocols - This routine finds the intersection of set
4574/// of protocols inherited from two distinct objective-c pointer objects.
4575/// It is used to build composite qualifier list of the composite type of
4576/// the conditional expression involving two objective-c pointer objects.
4577static
4578void getIntersectionOfProtocols(ASTContext &Context,
4579                                const ObjCObjectPointerType *LHSOPT,
4580                                const ObjCObjectPointerType *RHSOPT,
4581      llvm::SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
4582
4583  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4584  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4585  assert(LHS->getInterface() && "LHS must have an interface base");
4586  assert(RHS->getInterface() && "RHS must have an interface base");
4587
4588  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
4589  unsigned LHSNumProtocols = LHS->getNumProtocols();
4590  if (LHSNumProtocols > 0)
4591    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
4592  else {
4593    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4594    Context.CollectInheritedProtocols(LHS->getInterface(),
4595                                      LHSInheritedProtocols);
4596    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
4597                                LHSInheritedProtocols.end());
4598  }
4599
4600  unsigned RHSNumProtocols = RHS->getNumProtocols();
4601  if (RHSNumProtocols > 0) {
4602    ObjCProtocolDecl **RHSProtocols =
4603      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
4604    for (unsigned i = 0; i < RHSNumProtocols; ++i)
4605      if (InheritedProtocolSet.count(RHSProtocols[i]))
4606        IntersectionOfProtocols.push_back(RHSProtocols[i]);
4607  }
4608  else {
4609    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
4610    Context.CollectInheritedProtocols(RHS->getInterface(),
4611                                      RHSInheritedProtocols);
4612    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4613         RHSInheritedProtocols.begin(),
4614         E = RHSInheritedProtocols.end(); I != E; ++I)
4615      if (InheritedProtocolSet.count((*I)))
4616        IntersectionOfProtocols.push_back((*I));
4617  }
4618}
4619
4620/// areCommonBaseCompatible - Returns common base class of the two classes if
4621/// one found. Note that this is O'2 algorithm. But it will be called as the
4622/// last type comparison in a ?-exp of ObjC pointer types before a
4623/// warning is issued. So, its invokation is extremely rare.
4624QualType ASTContext::areCommonBaseCompatible(
4625                                          const ObjCObjectPointerType *Lptr,
4626                                          const ObjCObjectPointerType *Rptr) {
4627  const ObjCObjectType *LHS = Lptr->getObjectType();
4628  const ObjCObjectType *RHS = Rptr->getObjectType();
4629  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
4630  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
4631  if (!LDecl || !RDecl)
4632    return QualType();
4633
4634  while ((LDecl = LDecl->getSuperClass())) {
4635    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
4636    if (canAssignObjCInterfaces(LHS, RHS)) {
4637      llvm::SmallVector<ObjCProtocolDecl *, 8> Protocols;
4638      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
4639
4640      QualType Result = QualType(LHS, 0);
4641      if (!Protocols.empty())
4642        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
4643      Result = getObjCObjectPointerType(Result);
4644      return Result;
4645    }
4646  }
4647
4648  return QualType();
4649}
4650
4651bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
4652                                         const ObjCObjectType *RHS) {
4653  assert(LHS->getInterface() && "LHS is not an interface type");
4654  assert(RHS->getInterface() && "RHS is not an interface type");
4655
4656  // Verify that the base decls are compatible: the RHS must be a subclass of
4657  // the LHS.
4658  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
4659    return false;
4660
4661  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
4662  // protocol qualified at all, then we are good.
4663  if (LHS->getNumProtocols() == 0)
4664    return true;
4665
4666  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't, then it
4667  // isn't a superset.
4668  if (RHS->getNumProtocols() == 0)
4669    return true;  // FIXME: should return false!
4670
4671  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
4672                                     LHSPE = LHS->qual_end();
4673       LHSPI != LHSPE; LHSPI++) {
4674    bool RHSImplementsProtocol = false;
4675
4676    // If the RHS doesn't implement the protocol on the left, the types
4677    // are incompatible.
4678    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
4679                                       RHSPE = RHS->qual_end();
4680         RHSPI != RHSPE; RHSPI++) {
4681      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
4682        RHSImplementsProtocol = true;
4683        break;
4684      }
4685    }
4686    // FIXME: For better diagnostics, consider passing back the protocol name.
4687    if (!RHSImplementsProtocol)
4688      return false;
4689  }
4690  // The RHS implements all protocols listed on the LHS.
4691  return true;
4692}
4693
4694bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
4695  // get the "pointed to" types
4696  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
4697  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
4698
4699  if (!LHSOPT || !RHSOPT)
4700    return false;
4701
4702  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
4703         canAssignObjCInterfaces(RHSOPT, LHSOPT);
4704}
4705
4706bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
4707  return canAssignObjCInterfaces(
4708                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
4709                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
4710}
4711
4712/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
4713/// both shall have the identically qualified version of a compatible type.
4714/// C99 6.2.7p1: Two types have compatible types if their types are the
4715/// same. See 6.7.[2,3,5] for additional rules.
4716bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
4717                                    bool CompareUnqualified) {
4718  if (getLangOptions().CPlusPlus)
4719    return hasSameType(LHS, RHS);
4720
4721  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
4722}
4723
4724bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
4725  return !mergeTypes(LHS, RHS, true).isNull();
4726}
4727
4728/// mergeTransparentUnionType - if T is a transparent union type and a member
4729/// of T is compatible with SubType, return the merged type, else return
4730/// QualType()
4731QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
4732                                               bool OfBlockPointer,
4733                                               bool Unqualified) {
4734  if (const RecordType *UT = T->getAsUnionType()) {
4735    RecordDecl *UD = UT->getDecl();
4736    if (UD->hasAttr<TransparentUnionAttr>()) {
4737      for (RecordDecl::field_iterator it = UD->field_begin(),
4738           itend = UD->field_end(); it != itend; ++it) {
4739        QualType ET = it->getType().getUnqualifiedType();
4740        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
4741        if (!MT.isNull())
4742          return MT;
4743      }
4744    }
4745  }
4746
4747  return QualType();
4748}
4749
4750/// mergeFunctionArgumentTypes - merge two types which appear as function
4751/// argument types
4752QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
4753                                                bool OfBlockPointer,
4754                                                bool Unqualified) {
4755  // GNU extension: two types are compatible if they appear as a function
4756  // argument, one of the types is a transparent union type and the other
4757  // type is compatible with a union member
4758  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
4759                                              Unqualified);
4760  if (!lmerge.isNull())
4761    return lmerge;
4762
4763  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
4764                                              Unqualified);
4765  if (!rmerge.isNull())
4766    return rmerge;
4767
4768  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
4769}
4770
4771QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
4772                                        bool OfBlockPointer,
4773                                        bool Unqualified) {
4774  const FunctionType *lbase = lhs->getAs<FunctionType>();
4775  const FunctionType *rbase = rhs->getAs<FunctionType>();
4776  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
4777  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
4778  bool allLTypes = true;
4779  bool allRTypes = true;
4780
4781  // Check return type
4782  QualType retType;
4783  if (OfBlockPointer)
4784    retType = mergeTypes(rbase->getResultType(), lbase->getResultType(), true,
4785                         Unqualified);
4786  else
4787    retType = mergeTypes(lbase->getResultType(), rbase->getResultType(), false,
4788                         Unqualified);
4789  if (retType.isNull()) return QualType();
4790
4791  if (Unqualified)
4792    retType = retType.getUnqualifiedType();
4793
4794  CanQualType LRetType = getCanonicalType(lbase->getResultType());
4795  CanQualType RRetType = getCanonicalType(rbase->getResultType());
4796  if (Unqualified) {
4797    LRetType = LRetType.getUnqualifiedType();
4798    RRetType = RRetType.getUnqualifiedType();
4799  }
4800
4801  if (getCanonicalType(retType) != LRetType)
4802    allLTypes = false;
4803  if (getCanonicalType(retType) != RRetType)
4804    allRTypes = false;
4805
4806  // FIXME: double check this
4807  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
4808  //                           rbase->getRegParmAttr() != 0 &&
4809  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
4810  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
4811  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
4812
4813  // Compatible functions must have compatible calling conventions
4814  if (!isSameCallConv(lbaseInfo.getCC(), rbaseInfo.getCC()))
4815    return QualType();
4816
4817  // Regparm is part of the calling convention.
4818  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
4819    return QualType();
4820
4821  // It's noreturn if either type is.
4822  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
4823  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
4824  if (NoReturn != lbaseInfo.getNoReturn())
4825    allLTypes = false;
4826  if (NoReturn != rbaseInfo.getNoReturn())
4827    allRTypes = false;
4828
4829  FunctionType::ExtInfo einfo(NoReturn,
4830                              lbaseInfo.getRegParm(),
4831                              lbaseInfo.getCC());
4832
4833  if (lproto && rproto) { // two C99 style function prototypes
4834    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
4835           "C++ shouldn't be here");
4836    unsigned lproto_nargs = lproto->getNumArgs();
4837    unsigned rproto_nargs = rproto->getNumArgs();
4838
4839    // Compatible functions must have the same number of arguments
4840    if (lproto_nargs != rproto_nargs)
4841      return QualType();
4842
4843    // Variadic and non-variadic functions aren't compatible
4844    if (lproto->isVariadic() != rproto->isVariadic())
4845      return QualType();
4846
4847    if (lproto->getTypeQuals() != rproto->getTypeQuals())
4848      return QualType();
4849
4850    // Check argument compatibility
4851    llvm::SmallVector<QualType, 10> types;
4852    for (unsigned i = 0; i < lproto_nargs; i++) {
4853      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
4854      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
4855      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
4856                                                    OfBlockPointer,
4857                                                    Unqualified);
4858      if (argtype.isNull()) return QualType();
4859
4860      if (Unqualified)
4861        argtype = argtype.getUnqualifiedType();
4862
4863      types.push_back(argtype);
4864      if (Unqualified) {
4865        largtype = largtype.getUnqualifiedType();
4866        rargtype = rargtype.getUnqualifiedType();
4867      }
4868
4869      if (getCanonicalType(argtype) != getCanonicalType(largtype))
4870        allLTypes = false;
4871      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
4872        allRTypes = false;
4873    }
4874    if (allLTypes) return lhs;
4875    if (allRTypes) return rhs;
4876
4877    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
4878    EPI.ExtInfo = einfo;
4879    return getFunctionType(retType, types.begin(), types.size(), EPI);
4880  }
4881
4882  if (lproto) allRTypes = false;
4883  if (rproto) allLTypes = false;
4884
4885  const FunctionProtoType *proto = lproto ? lproto : rproto;
4886  if (proto) {
4887    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
4888    if (proto->isVariadic()) return QualType();
4889    // Check that the types are compatible with the types that
4890    // would result from default argument promotions (C99 6.7.5.3p15).
4891    // The only types actually affected are promotable integer
4892    // types and floats, which would be passed as a different
4893    // type depending on whether the prototype is visible.
4894    unsigned proto_nargs = proto->getNumArgs();
4895    for (unsigned i = 0; i < proto_nargs; ++i) {
4896      QualType argTy = proto->getArgType(i);
4897
4898      // Look at the promotion type of enum types, since that is the type used
4899      // to pass enum values.
4900      if (const EnumType *Enum = argTy->getAs<EnumType>())
4901        argTy = Enum->getDecl()->getPromotionType();
4902
4903      if (argTy->isPromotableIntegerType() ||
4904          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
4905        return QualType();
4906    }
4907
4908    if (allLTypes) return lhs;
4909    if (allRTypes) return rhs;
4910
4911    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
4912    EPI.ExtInfo = einfo;
4913    return getFunctionType(retType, proto->arg_type_begin(),
4914                           proto->getNumArgs(), EPI);
4915  }
4916
4917  if (allLTypes) return lhs;
4918  if (allRTypes) return rhs;
4919  return getFunctionNoProtoType(retType, einfo);
4920}
4921
4922QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
4923                                bool OfBlockPointer,
4924                                bool Unqualified) {
4925  // C++ [expr]: If an expression initially has the type "reference to T", the
4926  // type is adjusted to "T" prior to any further analysis, the expression
4927  // designates the object or function denoted by the reference, and the
4928  // expression is an lvalue unless the reference is an rvalue reference and
4929  // the expression is a function call (possibly inside parentheses).
4930  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
4931  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
4932
4933  if (Unqualified) {
4934    LHS = LHS.getUnqualifiedType();
4935    RHS = RHS.getUnqualifiedType();
4936  }
4937
4938  QualType LHSCan = getCanonicalType(LHS),
4939           RHSCan = getCanonicalType(RHS);
4940
4941  // If two types are identical, they are compatible.
4942  if (LHSCan == RHSCan)
4943    return LHS;
4944
4945  // If the qualifiers are different, the types aren't compatible... mostly.
4946  Qualifiers LQuals = LHSCan.getLocalQualifiers();
4947  Qualifiers RQuals = RHSCan.getLocalQualifiers();
4948  if (LQuals != RQuals) {
4949    // If any of these qualifiers are different, we have a type
4950    // mismatch.
4951    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
4952        LQuals.getAddressSpace() != RQuals.getAddressSpace())
4953      return QualType();
4954
4955    // Exactly one GC qualifier difference is allowed: __strong is
4956    // okay if the other type has no GC qualifier but is an Objective
4957    // C object pointer (i.e. implicitly strong by default).  We fix
4958    // this by pretending that the unqualified type was actually
4959    // qualified __strong.
4960    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
4961    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
4962    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
4963
4964    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
4965      return QualType();
4966
4967    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
4968      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
4969    }
4970    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
4971      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
4972    }
4973    return QualType();
4974  }
4975
4976  // Okay, qualifiers are equal.
4977
4978  Type::TypeClass LHSClass = LHSCan->getTypeClass();
4979  Type::TypeClass RHSClass = RHSCan->getTypeClass();
4980
4981  // We want to consider the two function types to be the same for these
4982  // comparisons, just force one to the other.
4983  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
4984  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
4985
4986  // Same as above for arrays
4987  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
4988    LHSClass = Type::ConstantArray;
4989  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
4990    RHSClass = Type::ConstantArray;
4991
4992  // ObjCInterfaces are just specialized ObjCObjects.
4993  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
4994  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
4995
4996  // Canonicalize ExtVector -> Vector.
4997  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
4998  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
4999
5000  // If the canonical type classes don't match.
5001  if (LHSClass != RHSClass) {
5002    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
5003    // a signed integer type, or an unsigned integer type.
5004    // Compatibility is based on the underlying type, not the promotion
5005    // type.
5006    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
5007      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
5008        return RHS;
5009    }
5010    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
5011      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
5012        return LHS;
5013    }
5014
5015    return QualType();
5016  }
5017
5018  // The canonical type classes match.
5019  switch (LHSClass) {
5020#define TYPE(Class, Base)
5021#define ABSTRACT_TYPE(Class, Base)
5022#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
5023#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
5024#define DEPENDENT_TYPE(Class, Base) case Type::Class:
5025#include "clang/AST/TypeNodes.def"
5026    assert(false && "Non-canonical and dependent types shouldn't get here");
5027    return QualType();
5028
5029  case Type::LValueReference:
5030  case Type::RValueReference:
5031  case Type::MemberPointer:
5032    assert(false && "C++ should never be in mergeTypes");
5033    return QualType();
5034
5035  case Type::ObjCInterface:
5036  case Type::IncompleteArray:
5037  case Type::VariableArray:
5038  case Type::FunctionProto:
5039  case Type::ExtVector:
5040    assert(false && "Types are eliminated above");
5041    return QualType();
5042
5043  case Type::Pointer:
5044  {
5045    // Merge two pointer types, while trying to preserve typedef info
5046    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
5047    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
5048    if (Unqualified) {
5049      LHSPointee = LHSPointee.getUnqualifiedType();
5050      RHSPointee = RHSPointee.getUnqualifiedType();
5051    }
5052    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
5053                                     Unqualified);
5054    if (ResultType.isNull()) return QualType();
5055    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5056      return LHS;
5057    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5058      return RHS;
5059    return getPointerType(ResultType);
5060  }
5061  case Type::BlockPointer:
5062  {
5063    // Merge two block pointer types, while trying to preserve typedef info
5064    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
5065    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
5066    if (Unqualified) {
5067      LHSPointee = LHSPointee.getUnqualifiedType();
5068      RHSPointee = RHSPointee.getUnqualifiedType();
5069    }
5070    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
5071                                     Unqualified);
5072    if (ResultType.isNull()) return QualType();
5073    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5074      return LHS;
5075    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5076      return RHS;
5077    return getBlockPointerType(ResultType);
5078  }
5079  case Type::ConstantArray:
5080  {
5081    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
5082    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
5083    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
5084      return QualType();
5085
5086    QualType LHSElem = getAsArrayType(LHS)->getElementType();
5087    QualType RHSElem = getAsArrayType(RHS)->getElementType();
5088    if (Unqualified) {
5089      LHSElem = LHSElem.getUnqualifiedType();
5090      RHSElem = RHSElem.getUnqualifiedType();
5091    }
5092
5093    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
5094    if (ResultType.isNull()) return QualType();
5095    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5096      return LHS;
5097    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5098      return RHS;
5099    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
5100                                          ArrayType::ArraySizeModifier(), 0);
5101    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
5102                                          ArrayType::ArraySizeModifier(), 0);
5103    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
5104    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
5105    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5106      return LHS;
5107    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5108      return RHS;
5109    if (LVAT) {
5110      // FIXME: This isn't correct! But tricky to implement because
5111      // the array's size has to be the size of LHS, but the type
5112      // has to be different.
5113      return LHS;
5114    }
5115    if (RVAT) {
5116      // FIXME: This isn't correct! But tricky to implement because
5117      // the array's size has to be the size of RHS, but the type
5118      // has to be different.
5119      return RHS;
5120    }
5121    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
5122    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
5123    return getIncompleteArrayType(ResultType,
5124                                  ArrayType::ArraySizeModifier(), 0);
5125  }
5126  case Type::FunctionNoProto:
5127    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
5128  case Type::Record:
5129  case Type::Enum:
5130    return QualType();
5131  case Type::Builtin:
5132    // Only exactly equal builtin types are compatible, which is tested above.
5133    return QualType();
5134  case Type::Complex:
5135    // Distinct complex types are incompatible.
5136    return QualType();
5137  case Type::Vector:
5138    // FIXME: The merged type should be an ExtVector!
5139    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
5140                             RHSCan->getAs<VectorType>()))
5141      return LHS;
5142    return QualType();
5143  case Type::ObjCObject: {
5144    // Check if the types are assignment compatible.
5145    // FIXME: This should be type compatibility, e.g. whether
5146    // "LHS x; RHS x;" at global scope is legal.
5147    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
5148    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
5149    if (canAssignObjCInterfaces(LHSIface, RHSIface))
5150      return LHS;
5151
5152    return QualType();
5153  }
5154  case Type::ObjCObjectPointer: {
5155    if (OfBlockPointer) {
5156      if (canAssignObjCInterfacesInBlockPointer(
5157                                          LHS->getAs<ObjCObjectPointerType>(),
5158                                          RHS->getAs<ObjCObjectPointerType>()))
5159      return LHS;
5160      return QualType();
5161    }
5162    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
5163                                RHS->getAs<ObjCObjectPointerType>()))
5164      return LHS;
5165
5166    return QualType();
5167    }
5168  }
5169
5170  return QualType();
5171}
5172
5173/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
5174/// 'RHS' attributes and returns the merged version; including for function
5175/// return types.
5176QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
5177  QualType LHSCan = getCanonicalType(LHS),
5178  RHSCan = getCanonicalType(RHS);
5179  // If two types are identical, they are compatible.
5180  if (LHSCan == RHSCan)
5181    return LHS;
5182  if (RHSCan->isFunctionType()) {
5183    if (!LHSCan->isFunctionType())
5184      return QualType();
5185    QualType OldReturnType =
5186      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
5187    QualType NewReturnType =
5188      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
5189    QualType ResReturnType =
5190      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
5191    if (ResReturnType.isNull())
5192      return QualType();
5193    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
5194      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
5195      // In either case, use OldReturnType to build the new function type.
5196      const FunctionType *F = LHS->getAs<FunctionType>();
5197      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
5198        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
5199        EPI.ExtInfo = getFunctionExtInfo(LHS);
5200        QualType ResultType
5201          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
5202                            FPT->getNumArgs(), EPI);
5203        return ResultType;
5204      }
5205    }
5206    return QualType();
5207  }
5208
5209  // If the qualifiers are different, the types can still be merged.
5210  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5211  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5212  if (LQuals != RQuals) {
5213    // If any of these qualifiers are different, we have a type mismatch.
5214    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5215        LQuals.getAddressSpace() != RQuals.getAddressSpace())
5216      return QualType();
5217
5218    // Exactly one GC qualifier difference is allowed: __strong is
5219    // okay if the other type has no GC qualifier but is an Objective
5220    // C object pointer (i.e. implicitly strong by default).  We fix
5221    // this by pretending that the unqualified type was actually
5222    // qualified __strong.
5223    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5224    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5225    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5226
5227    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5228      return QualType();
5229
5230    if (GC_L == Qualifiers::Strong)
5231      return LHS;
5232    if (GC_R == Qualifiers::Strong)
5233      return RHS;
5234    return QualType();
5235  }
5236
5237  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
5238    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5239    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5240    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
5241    if (ResQT == LHSBaseQT)
5242      return LHS;
5243    if (ResQT == RHSBaseQT)
5244      return RHS;
5245  }
5246  return QualType();
5247}
5248
5249//===----------------------------------------------------------------------===//
5250//                         Integer Predicates
5251//===----------------------------------------------------------------------===//
5252
5253unsigned ASTContext::getIntWidth(QualType T) {
5254  if (EnumType *ET = dyn_cast<EnumType>(T))
5255    T = ET->getDecl()->getIntegerType();
5256  if (T->isBooleanType())
5257    return 1;
5258  // For builtin types, just use the standard type sizing method
5259  return (unsigned)getTypeSize(T);
5260}
5261
5262QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
5263  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
5264
5265  // Turn <4 x signed int> -> <4 x unsigned int>
5266  if (const VectorType *VTy = T->getAs<VectorType>())
5267    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
5268                         VTy->getNumElements(), VTy->getVectorKind());
5269
5270  // For enums, we return the unsigned version of the base type.
5271  if (const EnumType *ETy = T->getAs<EnumType>())
5272    T = ETy->getDecl()->getIntegerType();
5273
5274  const BuiltinType *BTy = T->getAs<BuiltinType>();
5275  assert(BTy && "Unexpected signed integer type");
5276  switch (BTy->getKind()) {
5277  case BuiltinType::Char_S:
5278  case BuiltinType::SChar:
5279    return UnsignedCharTy;
5280  case BuiltinType::Short:
5281    return UnsignedShortTy;
5282  case BuiltinType::Int:
5283    return UnsignedIntTy;
5284  case BuiltinType::Long:
5285    return UnsignedLongTy;
5286  case BuiltinType::LongLong:
5287    return UnsignedLongLongTy;
5288  case BuiltinType::Int128:
5289    return UnsignedInt128Ty;
5290  default:
5291    assert(0 && "Unexpected signed integer type");
5292    return QualType();
5293  }
5294}
5295
5296ExternalASTSource::~ExternalASTSource() { }
5297
5298void ExternalASTSource::PrintStats() { }
5299
5300ASTMutationListener::~ASTMutationListener() { }
5301
5302
5303//===----------------------------------------------------------------------===//
5304//                          Builtin Type Computation
5305//===----------------------------------------------------------------------===//
5306
5307/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
5308/// pointer over the consumed characters.  This returns the resultant type.  If
5309/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
5310/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
5311/// a vector of "i*".
5312///
5313/// RequiresICE is filled in on return to indicate whether the value is required
5314/// to be an Integer Constant Expression.
5315static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
5316                                  ASTContext::GetBuiltinTypeError &Error,
5317                                  bool &RequiresICE,
5318                                  bool AllowTypeModifiers) {
5319  // Modifiers.
5320  int HowLong = 0;
5321  bool Signed = false, Unsigned = false;
5322  RequiresICE = false;
5323
5324  // Read the prefixed modifiers first.
5325  bool Done = false;
5326  while (!Done) {
5327    switch (*Str++) {
5328    default: Done = true; --Str; break;
5329    case 'I':
5330      RequiresICE = true;
5331      break;
5332    case 'S':
5333      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
5334      assert(!Signed && "Can't use 'S' modifier multiple times!");
5335      Signed = true;
5336      break;
5337    case 'U':
5338      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
5339      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
5340      Unsigned = true;
5341      break;
5342    case 'L':
5343      assert(HowLong <= 2 && "Can't have LLLL modifier");
5344      ++HowLong;
5345      break;
5346    }
5347  }
5348
5349  QualType Type;
5350
5351  // Read the base type.
5352  switch (*Str++) {
5353  default: assert(0 && "Unknown builtin type letter!");
5354  case 'v':
5355    assert(HowLong == 0 && !Signed && !Unsigned &&
5356           "Bad modifiers used with 'v'!");
5357    Type = Context.VoidTy;
5358    break;
5359  case 'f':
5360    assert(HowLong == 0 && !Signed && !Unsigned &&
5361           "Bad modifiers used with 'f'!");
5362    Type = Context.FloatTy;
5363    break;
5364  case 'd':
5365    assert(HowLong < 2 && !Signed && !Unsigned &&
5366           "Bad modifiers used with 'd'!");
5367    if (HowLong)
5368      Type = Context.LongDoubleTy;
5369    else
5370      Type = Context.DoubleTy;
5371    break;
5372  case 's':
5373    assert(HowLong == 0 && "Bad modifiers used with 's'!");
5374    if (Unsigned)
5375      Type = Context.UnsignedShortTy;
5376    else
5377      Type = Context.ShortTy;
5378    break;
5379  case 'i':
5380    if (HowLong == 3)
5381      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
5382    else if (HowLong == 2)
5383      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
5384    else if (HowLong == 1)
5385      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
5386    else
5387      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
5388    break;
5389  case 'c':
5390    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
5391    if (Signed)
5392      Type = Context.SignedCharTy;
5393    else if (Unsigned)
5394      Type = Context.UnsignedCharTy;
5395    else
5396      Type = Context.CharTy;
5397    break;
5398  case 'b': // boolean
5399    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
5400    Type = Context.BoolTy;
5401    break;
5402  case 'z':  // size_t.
5403    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
5404    Type = Context.getSizeType();
5405    break;
5406  case 'F':
5407    Type = Context.getCFConstantStringType();
5408    break;
5409  case 'G':
5410    Type = Context.getObjCIdType();
5411    break;
5412  case 'H':
5413    Type = Context.getObjCSelType();
5414    break;
5415  case 'a':
5416    Type = Context.getBuiltinVaListType();
5417    assert(!Type.isNull() && "builtin va list type not initialized!");
5418    break;
5419  case 'A':
5420    // This is a "reference" to a va_list; however, what exactly
5421    // this means depends on how va_list is defined. There are two
5422    // different kinds of va_list: ones passed by value, and ones
5423    // passed by reference.  An example of a by-value va_list is
5424    // x86, where va_list is a char*. An example of by-ref va_list
5425    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
5426    // we want this argument to be a char*&; for x86-64, we want
5427    // it to be a __va_list_tag*.
5428    Type = Context.getBuiltinVaListType();
5429    assert(!Type.isNull() && "builtin va list type not initialized!");
5430    if (Type->isArrayType())
5431      Type = Context.getArrayDecayedType(Type);
5432    else
5433      Type = Context.getLValueReferenceType(Type);
5434    break;
5435  case 'V': {
5436    char *End;
5437    unsigned NumElements = strtoul(Str, &End, 10);
5438    assert(End != Str && "Missing vector size");
5439    Str = End;
5440
5441    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
5442                                             RequiresICE, false);
5443    assert(!RequiresICE && "Can't require vector ICE");
5444
5445    // TODO: No way to make AltiVec vectors in builtins yet.
5446    Type = Context.getVectorType(ElementType, NumElements,
5447                                 VectorType::GenericVector);
5448    break;
5449  }
5450  case 'X': {
5451    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
5452                                             false);
5453    assert(!RequiresICE && "Can't require complex ICE");
5454    Type = Context.getComplexType(ElementType);
5455    break;
5456  }
5457  case 'P':
5458    Type = Context.getFILEType();
5459    if (Type.isNull()) {
5460      Error = ASTContext::GE_Missing_stdio;
5461      return QualType();
5462    }
5463    break;
5464  case 'J':
5465    if (Signed)
5466      Type = Context.getsigjmp_bufType();
5467    else
5468      Type = Context.getjmp_bufType();
5469
5470    if (Type.isNull()) {
5471      Error = ASTContext::GE_Missing_setjmp;
5472      return QualType();
5473    }
5474    break;
5475  }
5476
5477  // If there are modifiers and if we're allowed to parse them, go for it.
5478  Done = !AllowTypeModifiers;
5479  while (!Done) {
5480    switch (char c = *Str++) {
5481    default: Done = true; --Str; break;
5482    case '*':
5483    case '&': {
5484      // Both pointers and references can have their pointee types
5485      // qualified with an address space.
5486      char *End;
5487      unsigned AddrSpace = strtoul(Str, &End, 10);
5488      if (End != Str && AddrSpace != 0) {
5489        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
5490        Str = End;
5491      }
5492      if (c == '*')
5493        Type = Context.getPointerType(Type);
5494      else
5495        Type = Context.getLValueReferenceType(Type);
5496      break;
5497    }
5498    // FIXME: There's no way to have a built-in with an rvalue ref arg.
5499    case 'C':
5500      Type = Type.withConst();
5501      break;
5502    case 'D':
5503      Type = Context.getVolatileType(Type);
5504      break;
5505    }
5506  }
5507
5508  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
5509         "Integer constant 'I' type must be an integer");
5510
5511  return Type;
5512}
5513
5514/// GetBuiltinType - Return the type for the specified builtin.
5515QualType ASTContext::GetBuiltinType(unsigned Id,
5516                                    GetBuiltinTypeError &Error,
5517                                    unsigned *IntegerConstantArgs) {
5518  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
5519
5520  llvm::SmallVector<QualType, 8> ArgTypes;
5521
5522  bool RequiresICE = false;
5523  Error = GE_None;
5524  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
5525                                       RequiresICE, true);
5526  if (Error != GE_None)
5527    return QualType();
5528
5529  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
5530
5531  while (TypeStr[0] && TypeStr[0] != '.') {
5532    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
5533    if (Error != GE_None)
5534      return QualType();
5535
5536    // If this argument is required to be an IntegerConstantExpression and the
5537    // caller cares, fill in the bitmask we return.
5538    if (RequiresICE && IntegerConstantArgs)
5539      *IntegerConstantArgs |= 1 << ArgTypes.size();
5540
5541    // Do array -> pointer decay.  The builtin should use the decayed type.
5542    if (Ty->isArrayType())
5543      Ty = getArrayDecayedType(Ty);
5544
5545    ArgTypes.push_back(Ty);
5546  }
5547
5548  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
5549         "'.' should only occur at end of builtin type list!");
5550
5551  FunctionType::ExtInfo EI;
5552  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
5553
5554  bool Variadic = (TypeStr[0] == '.');
5555
5556  // We really shouldn't be making a no-proto type here, especially in C++.
5557  if (ArgTypes.empty() && Variadic)
5558    return getFunctionNoProtoType(ResType, EI);
5559
5560  FunctionProtoType::ExtProtoInfo EPI;
5561  EPI.ExtInfo = EI;
5562  EPI.Variadic = Variadic;
5563
5564  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(), EPI);
5565}
5566
5567GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
5568  GVALinkage External = GVA_StrongExternal;
5569
5570  Linkage L = FD->getLinkage();
5571  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5572      FD->getType()->getLinkage() == UniqueExternalLinkage)
5573    L = UniqueExternalLinkage;
5574
5575  switch (L) {
5576  case NoLinkage:
5577  case InternalLinkage:
5578  case UniqueExternalLinkage:
5579    return GVA_Internal;
5580
5581  case ExternalLinkage:
5582    switch (FD->getTemplateSpecializationKind()) {
5583    case TSK_Undeclared:
5584    case TSK_ExplicitSpecialization:
5585      External = GVA_StrongExternal;
5586      break;
5587
5588    case TSK_ExplicitInstantiationDefinition:
5589      return GVA_ExplicitTemplateInstantiation;
5590
5591    case TSK_ExplicitInstantiationDeclaration:
5592    case TSK_ImplicitInstantiation:
5593      External = GVA_TemplateInstantiation;
5594      break;
5595    }
5596  }
5597
5598  if (!FD->isInlined())
5599    return External;
5600
5601  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
5602    // GNU or C99 inline semantics. Determine whether this symbol should be
5603    // externally visible.
5604    if (FD->isInlineDefinitionExternallyVisible())
5605      return External;
5606
5607    // C99 inline semantics, where the symbol is not externally visible.
5608    return GVA_C99Inline;
5609  }
5610
5611  // C++0x [temp.explicit]p9:
5612  //   [ Note: The intent is that an inline function that is the subject of
5613  //   an explicit instantiation declaration will still be implicitly
5614  //   instantiated when used so that the body can be considered for
5615  //   inlining, but that no out-of-line copy of the inline function would be
5616  //   generated in the translation unit. -- end note ]
5617  if (FD->getTemplateSpecializationKind()
5618                                       == TSK_ExplicitInstantiationDeclaration)
5619    return GVA_C99Inline;
5620
5621  return GVA_CXXInline;
5622}
5623
5624GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
5625  // If this is a static data member, compute the kind of template
5626  // specialization. Otherwise, this variable is not part of a
5627  // template.
5628  TemplateSpecializationKind TSK = TSK_Undeclared;
5629  if (VD->isStaticDataMember())
5630    TSK = VD->getTemplateSpecializationKind();
5631
5632  Linkage L = VD->getLinkage();
5633  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5634      VD->getType()->getLinkage() == UniqueExternalLinkage)
5635    L = UniqueExternalLinkage;
5636
5637  switch (L) {
5638  case NoLinkage:
5639  case InternalLinkage:
5640  case UniqueExternalLinkage:
5641    return GVA_Internal;
5642
5643  case ExternalLinkage:
5644    switch (TSK) {
5645    case TSK_Undeclared:
5646    case TSK_ExplicitSpecialization:
5647      return GVA_StrongExternal;
5648
5649    case TSK_ExplicitInstantiationDeclaration:
5650      llvm_unreachable("Variable should not be instantiated");
5651      // Fall through to treat this like any other instantiation.
5652
5653    case TSK_ExplicitInstantiationDefinition:
5654      return GVA_ExplicitTemplateInstantiation;
5655
5656    case TSK_ImplicitInstantiation:
5657      return GVA_TemplateInstantiation;
5658    }
5659  }
5660
5661  return GVA_StrongExternal;
5662}
5663
5664bool ASTContext::DeclMustBeEmitted(const Decl *D) {
5665  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
5666    if (!VD->isFileVarDecl())
5667      return false;
5668  } else if (!isa<FunctionDecl>(D))
5669    return false;
5670
5671  // Weak references don't produce any output by themselves.
5672  if (D->hasAttr<WeakRefAttr>())
5673    return false;
5674
5675  // Aliases and used decls are required.
5676  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
5677    return true;
5678
5679  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
5680    // Forward declarations aren't required.
5681    if (!FD->isThisDeclarationADefinition())
5682      return false;
5683
5684    // Constructors and destructors are required.
5685    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
5686      return true;
5687
5688    // The key function for a class is required.
5689    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
5690      const CXXRecordDecl *RD = MD->getParent();
5691      if (MD->isOutOfLine() && RD->isDynamicClass()) {
5692        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
5693        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
5694          return true;
5695      }
5696    }
5697
5698    GVALinkage Linkage = GetGVALinkageForFunction(FD);
5699
5700    // static, static inline, always_inline, and extern inline functions can
5701    // always be deferred.  Normal inline functions can be deferred in C99/C++.
5702    // Implicit template instantiations can also be deferred in C++.
5703    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
5704        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
5705      return false;
5706    return true;
5707  }
5708
5709  const VarDecl *VD = cast<VarDecl>(D);
5710  assert(VD->isFileVarDecl() && "Expected file scoped var");
5711
5712  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
5713    return false;
5714
5715  // Structs that have non-trivial constructors or destructors are required.
5716
5717  // FIXME: Handle references.
5718  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
5719    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
5720      if (RD->hasDefinition() &&
5721          (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()))
5722        return true;
5723    }
5724  }
5725
5726  GVALinkage L = GetGVALinkageForVariable(VD);
5727  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
5728    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
5729      return false;
5730  }
5731
5732  return true;
5733}
5734
5735CallingConv ASTContext::getDefaultMethodCallConv() {
5736  // Pass through to the C++ ABI object
5737  return ABI->getDefaultMethodCallConv();
5738}
5739
5740bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) {
5741  // Pass through to the C++ ABI object
5742  return ABI->isNearlyEmpty(RD);
5743}
5744
5745CXXABI::~CXXABI() {}
5746