ASTContext.cpp revision dae0cb52e4e3d46bbfc9a4510909522197a92e54 
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::Typedef: {
815    const TypedefDecl *Typedef = cast<TypedefType>(T)->getDecl();
816    std::pair<uint64_t, unsigned> Info
817      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
818    Align = std::max(Typedef->getMaxAlignment(), Info.second);
819    Width = Info.first;
820    break;
821  }
822
823  case Type::TypeOfExpr:
824    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
825                         .getTypePtr());
826
827  case Type::TypeOf:
828    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
829
830  case Type::Decltype:
831    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
832                        .getTypePtr());
833
834  case Type::Elaborated:
835    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
836
837  case Type::TemplateSpecialization:
838    assert(getCanonicalType(T) != T &&
839           "Cannot request the size of a dependent type");
840    // FIXME: this is likely to be wrong once we support template
841    // aliases, since a template alias could refer to a typedef that
842    // has an __aligned__ attribute on it.
843    return getTypeInfo(getCanonicalType(T));
844  }
845
846  assert(Align && (Align & (Align-1)) == 0 && "Alignment must be power of 2");
847  return std::make_pair(Width, Align);
848}
849
850/// getTypeSizeInChars - Return the size of the specified type, in characters.
851/// This method does not work on incomplete types.
852CharUnits ASTContext::getTypeSizeInChars(QualType T) {
853  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
854}
855CharUnits ASTContext::getTypeSizeInChars(const Type *T) {
856  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
857}
858
859/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
860/// characters. This method does not work on incomplete types.
861CharUnits ASTContext::getTypeAlignInChars(QualType T) {
862  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
863}
864CharUnits ASTContext::getTypeAlignInChars(const Type *T) {
865  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
866}
867
868/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
869/// type for the current target in bits.  This can be different than the ABI
870/// alignment in cases where it is beneficial for performance to overalign
871/// a data type.
872unsigned ASTContext::getPreferredTypeAlign(const Type *T) {
873  unsigned ABIAlign = getTypeAlign(T);
874
875  // Double and long long should be naturally aligned if possible.
876  if (const ComplexType* CT = T->getAs<ComplexType>())
877    T = CT->getElementType().getTypePtr();
878  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
879      T->isSpecificBuiltinType(BuiltinType::LongLong))
880    return std::max(ABIAlign, (unsigned)getTypeSize(T));
881
882  return ABIAlign;
883}
884
885/// ShallowCollectObjCIvars -
886/// Collect all ivars, including those synthesized, in the current class.
887///
888void ASTContext::ShallowCollectObjCIvars(const ObjCInterfaceDecl *OI,
889                                 llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
890  // FIXME. This need be removed but there are two many places which
891  // assume const-ness of ObjCInterfaceDecl
892  ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
893  for (ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
894        Iv= Iv->getNextIvar())
895    Ivars.push_back(Iv);
896}
897
898/// DeepCollectObjCIvars -
899/// This routine first collects all declared, but not synthesized, ivars in
900/// super class and then collects all ivars, including those synthesized for
901/// current class. This routine is used for implementation of current class
902/// when all ivars, declared and synthesized are known.
903///
904void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
905                                      bool leafClass,
906                                llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
907  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
908    DeepCollectObjCIvars(SuperClass, false, Ivars);
909  if (!leafClass) {
910    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
911         E = OI->ivar_end(); I != E; ++I)
912      Ivars.push_back(*I);
913  }
914  else
915    ShallowCollectObjCIvars(OI, Ivars);
916}
917
918/// CollectInheritedProtocols - Collect all protocols in current class and
919/// those inherited by it.
920void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
921                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
922  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
923    // We can use protocol_iterator here instead of
924    // all_referenced_protocol_iterator since we are walking all categories.
925    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
926         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
927      ObjCProtocolDecl *Proto = (*P);
928      Protocols.insert(Proto);
929      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
930           PE = Proto->protocol_end(); P != PE; ++P) {
931        Protocols.insert(*P);
932        CollectInheritedProtocols(*P, Protocols);
933      }
934    }
935
936    // Categories of this Interface.
937    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
938         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
939      CollectInheritedProtocols(CDeclChain, Protocols);
940    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
941      while (SD) {
942        CollectInheritedProtocols(SD, Protocols);
943        SD = SD->getSuperClass();
944      }
945  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
946    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
947         PE = OC->protocol_end(); P != PE; ++P) {
948      ObjCProtocolDecl *Proto = (*P);
949      Protocols.insert(Proto);
950      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
951           PE = Proto->protocol_end(); P != PE; ++P)
952        CollectInheritedProtocols(*P, Protocols);
953    }
954  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
955    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
956         PE = OP->protocol_end(); P != PE; ++P) {
957      ObjCProtocolDecl *Proto = (*P);
958      Protocols.insert(Proto);
959      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
960           PE = Proto->protocol_end(); P != PE; ++P)
961        CollectInheritedProtocols(*P, Protocols);
962    }
963  }
964}
965
966unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) {
967  unsigned count = 0;
968  // Count ivars declared in class extension.
969  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
970       CDecl = CDecl->getNextClassExtension())
971    count += CDecl->ivar_size();
972
973  // Count ivar defined in this class's implementation.  This
974  // includes synthesized ivars.
975  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
976    count += ImplDecl->ivar_size();
977
978  return count;
979}
980
981/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
982ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
983  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
984    I = ObjCImpls.find(D);
985  if (I != ObjCImpls.end())
986    return cast<ObjCImplementationDecl>(I->second);
987  return 0;
988}
989/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
990ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
991  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
992    I = ObjCImpls.find(D);
993  if (I != ObjCImpls.end())
994    return cast<ObjCCategoryImplDecl>(I->second);
995  return 0;
996}
997
998/// \brief Set the implementation of ObjCInterfaceDecl.
999void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1000                           ObjCImplementationDecl *ImplD) {
1001  assert(IFaceD && ImplD && "Passed null params");
1002  ObjCImpls[IFaceD] = ImplD;
1003}
1004/// \brief Set the implementation of ObjCCategoryDecl.
1005void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1006                           ObjCCategoryImplDecl *ImplD) {
1007  assert(CatD && ImplD && "Passed null params");
1008  ObjCImpls[CatD] = ImplD;
1009}
1010
1011/// \brief Allocate an uninitialized TypeSourceInfo.
1012///
1013/// The caller should initialize the memory held by TypeSourceInfo using
1014/// the TypeLoc wrappers.
1015///
1016/// \param T the type that will be the basis for type source info. This type
1017/// should refer to how the declarator was written in source code, not to
1018/// what type semantic analysis resolved the declarator to.
1019TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1020                                                 unsigned DataSize) {
1021  if (!DataSize)
1022    DataSize = TypeLoc::getFullDataSizeForType(T);
1023  else
1024    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1025           "incorrect data size provided to CreateTypeSourceInfo!");
1026
1027  TypeSourceInfo *TInfo =
1028    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1029  new (TInfo) TypeSourceInfo(T);
1030  return TInfo;
1031}
1032
1033TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1034                                                     SourceLocation L) {
1035  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1036  DI->getTypeLoc().initialize(L);
1037  return DI;
1038}
1039
1040const ASTRecordLayout &
1041ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) {
1042  return getObjCLayout(D, 0);
1043}
1044
1045const ASTRecordLayout &
1046ASTContext::getASTObjCImplementationLayout(const ObjCImplementationDecl *D) {
1047  return getObjCLayout(D->getClassInterface(), D);
1048}
1049
1050//===----------------------------------------------------------------------===//
1051//                   Type creation/memoization methods
1052//===----------------------------------------------------------------------===//
1053
1054QualType ASTContext::getExtQualType(const Type *TypeNode, Qualifiers Quals) {
1055  unsigned Fast = Quals.getFastQualifiers();
1056  Quals.removeFastQualifiers();
1057
1058  // Check if we've already instantiated this type.
1059  llvm::FoldingSetNodeID ID;
1060  ExtQuals::Profile(ID, TypeNode, Quals);
1061  void *InsertPos = 0;
1062  if (ExtQuals *EQ = ExtQualNodes.FindNodeOrInsertPos(ID, InsertPos)) {
1063    assert(EQ->getQualifiers() == Quals);
1064    QualType T = QualType(EQ, Fast);
1065    return T;
1066  }
1067
1068  ExtQuals *New = new (*this, TypeAlignment) ExtQuals(*this, TypeNode, Quals);
1069  ExtQualNodes.InsertNode(New, InsertPos);
1070  QualType T = QualType(New, Fast);
1071  return T;
1072}
1073
1074QualType ASTContext::getVolatileType(QualType T) {
1075  QualType CanT = getCanonicalType(T);
1076  if (CanT.isVolatileQualified()) return T;
1077
1078  QualifierCollector Quals;
1079  const Type *TypeNode = Quals.strip(T);
1080  Quals.addVolatile();
1081
1082  return getExtQualType(TypeNode, Quals);
1083}
1084
1085QualType ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) {
1086  QualType CanT = getCanonicalType(T);
1087  if (CanT.getAddressSpace() == AddressSpace)
1088    return T;
1089
1090  // If we are composing extended qualifiers together, merge together
1091  // into one ExtQuals node.
1092  QualifierCollector Quals;
1093  const Type *TypeNode = Quals.strip(T);
1094
1095  // If this type already has an address space specified, it cannot get
1096  // another one.
1097  assert(!Quals.hasAddressSpace() &&
1098         "Type cannot be in multiple addr spaces!");
1099  Quals.addAddressSpace(AddressSpace);
1100
1101  return getExtQualType(TypeNode, Quals);
1102}
1103
1104QualType ASTContext::getObjCGCQualType(QualType T,
1105                                       Qualifiers::GC GCAttr) {
1106  QualType CanT = getCanonicalType(T);
1107  if (CanT.getObjCGCAttr() == GCAttr)
1108    return T;
1109
1110  if (T->isPointerType()) {
1111    QualType Pointee = T->getAs<PointerType>()->getPointeeType();
1112    if (Pointee->isAnyPointerType()) {
1113      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1114      return getPointerType(ResultType);
1115    }
1116  }
1117
1118  // If we are composing extended qualifiers together, merge together
1119  // into one ExtQuals node.
1120  QualifierCollector Quals;
1121  const Type *TypeNode = Quals.strip(T);
1122
1123  // If this type already has an ObjCGC specified, it cannot get
1124  // another one.
1125  assert(!Quals.hasObjCGCAttr() &&
1126         "Type cannot have multiple ObjCGCs!");
1127  Quals.addObjCGCAttr(GCAttr);
1128
1129  return getExtQualType(TypeNode, Quals);
1130}
1131
1132static QualType getExtFunctionType(ASTContext& Context, QualType T,
1133                                        const FunctionType::ExtInfo &Info) {
1134  QualType ResultType;
1135  if (const PointerType *Pointer = T->getAs<PointerType>()) {
1136    QualType Pointee = Pointer->getPointeeType();
1137    ResultType = getExtFunctionType(Context, Pointee, Info);
1138    if (ResultType == Pointee)
1139      return T;
1140
1141    ResultType = Context.getPointerType(ResultType);
1142  } else if (const BlockPointerType *BlockPointer
1143                                              = T->getAs<BlockPointerType>()) {
1144    QualType Pointee = BlockPointer->getPointeeType();
1145    ResultType = getExtFunctionType(Context, Pointee, Info);
1146    if (ResultType == Pointee)
1147      return T;
1148
1149    ResultType = Context.getBlockPointerType(ResultType);
1150  } else if (const MemberPointerType *MemberPointer
1151                                            = T->getAs<MemberPointerType>()) {
1152    QualType Pointee = MemberPointer->getPointeeType();
1153    ResultType = getExtFunctionType(Context, Pointee, Info);
1154    if (ResultType == Pointee)
1155      return T;
1156
1157    ResultType = Context.getMemberPointerType(ResultType,
1158                                              MemberPointer->getClass());
1159   } else if (const FunctionType *F = T->getAs<FunctionType>()) {
1160    if (F->getExtInfo() == Info)
1161      return T;
1162
1163    if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(F)) {
1164      ResultType = Context.getFunctionNoProtoType(FNPT->getResultType(),
1165                                                  Info);
1166    } else {
1167      const FunctionProtoType *FPT = cast<FunctionProtoType>(F);
1168      ResultType
1169        = Context.getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1170                                  FPT->getNumArgs(), FPT->isVariadic(),
1171                                  FPT->getTypeQuals(),
1172                                  FPT->hasExceptionSpec(),
1173                                  FPT->hasAnyExceptionSpec(),
1174                                  FPT->getNumExceptions(),
1175                                  FPT->exception_begin(),
1176                                  Info);
1177    }
1178  } else
1179    return T;
1180
1181  return Context.getQualifiedType(ResultType, T.getLocalQualifiers());
1182}
1183
1184QualType ASTContext::getNoReturnType(QualType T, bool AddNoReturn) {
1185  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1186  return getExtFunctionType(*this, T,
1187                                 Info.withNoReturn(AddNoReturn));
1188}
1189
1190QualType ASTContext::getCallConvType(QualType T, CallingConv CallConv) {
1191  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1192  return getExtFunctionType(*this, T,
1193                            Info.withCallingConv(CallConv));
1194}
1195
1196QualType ASTContext::getRegParmType(QualType T, unsigned RegParm) {
1197  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1198  return getExtFunctionType(*this, T,
1199                                 Info.withRegParm(RegParm));
1200}
1201
1202/// getComplexType - Return the uniqued reference to the type for a complex
1203/// number with the specified element type.
1204QualType ASTContext::getComplexType(QualType T) {
1205  // Unique pointers, to guarantee there is only one pointer of a particular
1206  // structure.
1207  llvm::FoldingSetNodeID ID;
1208  ComplexType::Profile(ID, T);
1209
1210  void *InsertPos = 0;
1211  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1212    return QualType(CT, 0);
1213
1214  // If the pointee type isn't canonical, this won't be a canonical type either,
1215  // so fill in the canonical type field.
1216  QualType Canonical;
1217  if (!T.isCanonical()) {
1218    Canonical = getComplexType(getCanonicalType(T));
1219
1220    // Get the new insert position for the node we care about.
1221    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1222    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1223  }
1224  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1225  Types.push_back(New);
1226  ComplexTypes.InsertNode(New, InsertPos);
1227  return QualType(New, 0);
1228}
1229
1230/// getPointerType - Return the uniqued reference to the type for a pointer to
1231/// the specified type.
1232QualType ASTContext::getPointerType(QualType T) {
1233  // Unique pointers, to guarantee there is only one pointer of a particular
1234  // structure.
1235  llvm::FoldingSetNodeID ID;
1236  PointerType::Profile(ID, T);
1237
1238  void *InsertPos = 0;
1239  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1240    return QualType(PT, 0);
1241
1242  // If the pointee type isn't canonical, this won't be a canonical type either,
1243  // so fill in the canonical type field.
1244  QualType Canonical;
1245  if (!T.isCanonical()) {
1246    Canonical = getPointerType(getCanonicalType(T));
1247
1248    // Get the new insert position for the node we care about.
1249    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1250    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1251  }
1252  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1253  Types.push_back(New);
1254  PointerTypes.InsertNode(New, InsertPos);
1255  return QualType(New, 0);
1256}
1257
1258/// getBlockPointerType - Return the uniqued reference to the type for
1259/// a pointer to the specified block.
1260QualType ASTContext::getBlockPointerType(QualType T) {
1261  assert(T->isFunctionType() && "block of function types only");
1262  // Unique pointers, to guarantee there is only one block of a particular
1263  // structure.
1264  llvm::FoldingSetNodeID ID;
1265  BlockPointerType::Profile(ID, T);
1266
1267  void *InsertPos = 0;
1268  if (BlockPointerType *PT =
1269        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1270    return QualType(PT, 0);
1271
1272  // If the block pointee type isn't canonical, this won't be a canonical
1273  // type either so fill in the canonical type field.
1274  QualType Canonical;
1275  if (!T.isCanonical()) {
1276    Canonical = getBlockPointerType(getCanonicalType(T));
1277
1278    // Get the new insert position for the node we care about.
1279    BlockPointerType *NewIP =
1280      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1281    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1282  }
1283  BlockPointerType *New
1284    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1285  Types.push_back(New);
1286  BlockPointerTypes.InsertNode(New, InsertPos);
1287  return QualType(New, 0);
1288}
1289
1290/// getLValueReferenceType - Return the uniqued reference to the type for an
1291/// lvalue reference to the specified type.
1292QualType ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) {
1293  // Unique pointers, to guarantee there is only one pointer of a particular
1294  // structure.
1295  llvm::FoldingSetNodeID ID;
1296  ReferenceType::Profile(ID, T, SpelledAsLValue);
1297
1298  void *InsertPos = 0;
1299  if (LValueReferenceType *RT =
1300        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1301    return QualType(RT, 0);
1302
1303  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1304
1305  // If the referencee type isn't canonical, this won't be a canonical type
1306  // either, so fill in the canonical type field.
1307  QualType Canonical;
1308  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1309    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1310    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1311
1312    // Get the new insert position for the node we care about.
1313    LValueReferenceType *NewIP =
1314      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1315    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1316  }
1317
1318  LValueReferenceType *New
1319    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1320                                                     SpelledAsLValue);
1321  Types.push_back(New);
1322  LValueReferenceTypes.InsertNode(New, InsertPos);
1323
1324  return QualType(New, 0);
1325}
1326
1327/// getRValueReferenceType - Return the uniqued reference to the type for an
1328/// rvalue reference to the specified type.
1329QualType ASTContext::getRValueReferenceType(QualType T) {
1330  // Unique pointers, to guarantee there is only one pointer of a particular
1331  // structure.
1332  llvm::FoldingSetNodeID ID;
1333  ReferenceType::Profile(ID, T, false);
1334
1335  void *InsertPos = 0;
1336  if (RValueReferenceType *RT =
1337        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1338    return QualType(RT, 0);
1339
1340  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1341
1342  // If the referencee type isn't canonical, this won't be a canonical type
1343  // either, so fill in the canonical type field.
1344  QualType Canonical;
1345  if (InnerRef || !T.isCanonical()) {
1346    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1347    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1348
1349    // Get the new insert position for the node we care about.
1350    RValueReferenceType *NewIP =
1351      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1352    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1353  }
1354
1355  RValueReferenceType *New
1356    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1357  Types.push_back(New);
1358  RValueReferenceTypes.InsertNode(New, InsertPos);
1359  return QualType(New, 0);
1360}
1361
1362/// getMemberPointerType - Return the uniqued reference to the type for a
1363/// member pointer to the specified type, in the specified class.
1364QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) {
1365  // Unique pointers, to guarantee there is only one pointer of a particular
1366  // structure.
1367  llvm::FoldingSetNodeID ID;
1368  MemberPointerType::Profile(ID, T, Cls);
1369
1370  void *InsertPos = 0;
1371  if (MemberPointerType *PT =
1372      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1373    return QualType(PT, 0);
1374
1375  // If the pointee or class type isn't canonical, this won't be a canonical
1376  // type either, so fill in the canonical type field.
1377  QualType Canonical;
1378  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1379    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1380
1381    // Get the new insert position for the node we care about.
1382    MemberPointerType *NewIP =
1383      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1384    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1385  }
1386  MemberPointerType *New
1387    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1388  Types.push_back(New);
1389  MemberPointerTypes.InsertNode(New, InsertPos);
1390  return QualType(New, 0);
1391}
1392
1393/// getConstantArrayType - Return the unique reference to the type for an
1394/// array of the specified element type.
1395QualType ASTContext::getConstantArrayType(QualType EltTy,
1396                                          const llvm::APInt &ArySizeIn,
1397                                          ArrayType::ArraySizeModifier ASM,
1398                                          unsigned EltTypeQuals) {
1399  assert((EltTy->isDependentType() ||
1400          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1401         "Constant array of VLAs is illegal!");
1402
1403  // Convert the array size into a canonical width matching the pointer size for
1404  // the target.
1405  llvm::APInt ArySize(ArySizeIn);
1406  ArySize.zextOrTrunc(Target.getPointerWidth(EltTy.getAddressSpace()));
1407
1408  llvm::FoldingSetNodeID ID;
1409  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, EltTypeQuals);
1410
1411  void *InsertPos = 0;
1412  if (ConstantArrayType *ATP =
1413      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1414    return QualType(ATP, 0);
1415
1416  // If the element type isn't canonical, this won't be a canonical type either,
1417  // so fill in the canonical type field.
1418  QualType Canonical;
1419  if (!EltTy.isCanonical()) {
1420    Canonical = getConstantArrayType(getCanonicalType(EltTy), ArySize,
1421                                     ASM, EltTypeQuals);
1422    // Get the new insert position for the node we care about.
1423    ConstantArrayType *NewIP =
1424      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1425    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1426  }
1427
1428  ConstantArrayType *New = new(*this,TypeAlignment)
1429    ConstantArrayType(EltTy, Canonical, ArySize, ASM, EltTypeQuals);
1430  ConstantArrayTypes.InsertNode(New, InsertPos);
1431  Types.push_back(New);
1432  return QualType(New, 0);
1433}
1434
1435/// getIncompleteArrayType - Returns a unique reference to the type for a
1436/// incomplete array of the specified element type.
1437QualType ASTContext::getUnknownSizeVariableArrayType(QualType Ty) {
1438  QualType ElemTy = getBaseElementType(Ty);
1439  DeclarationName Name;
1440  llvm::SmallVector<QualType, 8> ATypes;
1441  QualType ATy = Ty;
1442  while (const ArrayType *AT = getAsArrayType(ATy)) {
1443    ATypes.push_back(ATy);
1444    ATy = AT->getElementType();
1445  }
1446  for (int i = ATypes.size() - 1; i >= 0; i--) {
1447    if (const VariableArrayType *VAT = getAsVariableArrayType(ATypes[i])) {
1448      ElemTy = getVariableArrayType(ElemTy, /*ArraySize*/0, ArrayType::Star,
1449                                    0, VAT->getBracketsRange());
1450    }
1451    else if (const ConstantArrayType *CAT = getAsConstantArrayType(ATypes[i])) {
1452      llvm::APSInt ConstVal(CAT->getSize());
1453      ElemTy = getConstantArrayType(ElemTy, ConstVal, ArrayType::Normal, 0);
1454    }
1455    else if (getAsIncompleteArrayType(ATypes[i])) {
1456      ElemTy = getVariableArrayType(ElemTy, /*ArraySize*/0, ArrayType::Normal,
1457                                    0, SourceRange());
1458    }
1459    else
1460      assert(false && "DependentArrayType is seen");
1461  }
1462  return ElemTy;
1463}
1464
1465/// getVariableArrayDecayedType - Returns a vla type where known sizes
1466/// are replaced with [*]
1467QualType ASTContext::getVariableArrayDecayedType(QualType Ty) {
1468  if (Ty->isPointerType()) {
1469    QualType BaseType = Ty->getAs<PointerType>()->getPointeeType();
1470    if (isa<VariableArrayType>(BaseType)) {
1471      ArrayType *AT = dyn_cast<ArrayType>(BaseType);
1472      VariableArrayType *VAT = cast<VariableArrayType>(AT);
1473      if (VAT->getSizeExpr()) {
1474        Ty = getUnknownSizeVariableArrayType(BaseType);
1475        Ty = getPointerType(Ty);
1476      }
1477    }
1478  }
1479  return Ty;
1480}
1481
1482
1483/// getVariableArrayType - Returns a non-unique reference to the type for a
1484/// variable array of the specified element type.
1485QualType ASTContext::getVariableArrayType(QualType EltTy,
1486                                          Expr *NumElts,
1487                                          ArrayType::ArraySizeModifier ASM,
1488                                          unsigned EltTypeQuals,
1489                                          SourceRange Brackets) {
1490  // Since we don't unique expressions, it isn't possible to unique VLA's
1491  // that have an expression provided for their size.
1492  QualType CanonType;
1493
1494  if (!EltTy.isCanonical()) {
1495    CanonType = getVariableArrayType(getCanonicalType(EltTy), NumElts, ASM,
1496                                     EltTypeQuals, Brackets);
1497  }
1498
1499  VariableArrayType *New = new(*this, TypeAlignment)
1500    VariableArrayType(EltTy, CanonType, NumElts, ASM, EltTypeQuals, Brackets);
1501
1502  VariableArrayTypes.push_back(New);
1503  Types.push_back(New);
1504  return QualType(New, 0);
1505}
1506
1507/// getDependentSizedArrayType - Returns a non-unique reference to
1508/// the type for a dependently-sized array of the specified element
1509/// type.
1510QualType ASTContext::getDependentSizedArrayType(QualType EltTy,
1511                                                Expr *NumElts,
1512                                                ArrayType::ArraySizeModifier ASM,
1513                                                unsigned EltTypeQuals,
1514                                                SourceRange Brackets) {
1515  assert((!NumElts || NumElts->isTypeDependent() ||
1516          NumElts->isValueDependent()) &&
1517         "Size must be type- or value-dependent!");
1518
1519  void *InsertPos = 0;
1520  DependentSizedArrayType *Canon = 0;
1521  llvm::FoldingSetNodeID ID;
1522
1523  QualType CanonicalEltTy = getCanonicalType(EltTy);
1524  if (NumElts) {
1525    // Dependently-sized array types that do not have a specified
1526    // number of elements will have their sizes deduced from an
1527    // initializer.
1528    DependentSizedArrayType::Profile(ID, *this, CanonicalEltTy, ASM,
1529                                     EltTypeQuals, NumElts);
1530
1531    Canon = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1532  }
1533
1534  DependentSizedArrayType *New;
1535  if (Canon) {
1536    // We already have a canonical version of this array type; use it as
1537    // the canonical type for a newly-built type.
1538    New = new (*this, TypeAlignment)
1539      DependentSizedArrayType(*this, EltTy, QualType(Canon, 0),
1540                              NumElts, ASM, EltTypeQuals, Brackets);
1541  } else if (CanonicalEltTy == EltTy) {
1542    // This is a canonical type. Record it.
1543    New = new (*this, TypeAlignment)
1544      DependentSizedArrayType(*this, EltTy, QualType(),
1545                              NumElts, ASM, EltTypeQuals, Brackets);
1546
1547    if (NumElts) {
1548#ifndef NDEBUG
1549      DependentSizedArrayType *CanonCheck
1550        = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1551      assert(!CanonCheck && "Dependent-sized canonical array type broken");
1552      (void)CanonCheck;
1553#endif
1554      DependentSizedArrayTypes.InsertNode(New, InsertPos);
1555    }
1556  } else {
1557    QualType Canon = getDependentSizedArrayType(CanonicalEltTy, NumElts,
1558                                                ASM, EltTypeQuals,
1559                                                SourceRange());
1560    New = new (*this, TypeAlignment)
1561      DependentSizedArrayType(*this, EltTy, Canon,
1562                              NumElts, ASM, EltTypeQuals, Brackets);
1563  }
1564
1565  Types.push_back(New);
1566  return QualType(New, 0);
1567}
1568
1569QualType ASTContext::getIncompleteArrayType(QualType EltTy,
1570                                            ArrayType::ArraySizeModifier ASM,
1571                                            unsigned EltTypeQuals) {
1572  llvm::FoldingSetNodeID ID;
1573  IncompleteArrayType::Profile(ID, EltTy, ASM, EltTypeQuals);
1574
1575  void *InsertPos = 0;
1576  if (IncompleteArrayType *ATP =
1577       IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1578    return QualType(ATP, 0);
1579
1580  // If the element type isn't canonical, this won't be a canonical type
1581  // either, so fill in the canonical type field.
1582  QualType Canonical;
1583
1584  if (!EltTy.isCanonical()) {
1585    Canonical = getIncompleteArrayType(getCanonicalType(EltTy),
1586                                       ASM, EltTypeQuals);
1587
1588    // Get the new insert position for the node we care about.
1589    IncompleteArrayType *NewIP =
1590      IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1591    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1592  }
1593
1594  IncompleteArrayType *New = new (*this, TypeAlignment)
1595    IncompleteArrayType(EltTy, Canonical, ASM, EltTypeQuals);
1596
1597  IncompleteArrayTypes.InsertNode(New, InsertPos);
1598  Types.push_back(New);
1599  return QualType(New, 0);
1600}
1601
1602/// getVectorType - Return the unique reference to a vector type of
1603/// the specified element type and size. VectorType must be a built-in type.
1604QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1605                                   VectorType::VectorKind VecKind) {
1606  BuiltinType *BaseType;
1607
1608  BaseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1609  assert(BaseType != 0 && "getVectorType(): Expecting a built-in type");
1610
1611  // Check if we've already instantiated a vector of this type.
1612  llvm::FoldingSetNodeID ID;
1613  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
1614
1615  void *InsertPos = 0;
1616  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1617    return QualType(VTP, 0);
1618
1619  // If the element type isn't canonical, this won't be a canonical type either,
1620  // so fill in the canonical type field.
1621  QualType Canonical;
1622  if (!vecType.isCanonical()) {
1623    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
1624
1625    // Get the new insert position for the node we care about.
1626    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1627    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1628  }
1629  VectorType *New = new (*this, TypeAlignment)
1630    VectorType(vecType, NumElts, Canonical, VecKind);
1631  VectorTypes.InsertNode(New, InsertPos);
1632  Types.push_back(New);
1633  return QualType(New, 0);
1634}
1635
1636/// getExtVectorType - Return the unique reference to an extended vector type of
1637/// the specified element type and size. VectorType must be a built-in type.
1638QualType ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) {
1639  BuiltinType *baseType;
1640
1641  baseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1642  assert(baseType != 0 && "getExtVectorType(): Expecting a built-in type");
1643
1644  // Check if we've already instantiated a vector of this type.
1645  llvm::FoldingSetNodeID ID;
1646  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1647                      VectorType::GenericVector);
1648  void *InsertPos = 0;
1649  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1650    return QualType(VTP, 0);
1651
1652  // If the element type isn't canonical, this won't be a canonical type either,
1653  // so fill in the canonical type field.
1654  QualType Canonical;
1655  if (!vecType.isCanonical()) {
1656    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
1657
1658    // Get the new insert position for the node we care about.
1659    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1660    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1661  }
1662  ExtVectorType *New = new (*this, TypeAlignment)
1663    ExtVectorType(vecType, NumElts, Canonical);
1664  VectorTypes.InsertNode(New, InsertPos);
1665  Types.push_back(New);
1666  return QualType(New, 0);
1667}
1668
1669QualType ASTContext::getDependentSizedExtVectorType(QualType vecType,
1670                                                    Expr *SizeExpr,
1671                                                    SourceLocation AttrLoc) {
1672  llvm::FoldingSetNodeID ID;
1673  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
1674                                       SizeExpr);
1675
1676  void *InsertPos = 0;
1677  DependentSizedExtVectorType *Canon
1678    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1679  DependentSizedExtVectorType *New;
1680  if (Canon) {
1681    // We already have a canonical version of this array type; use it as
1682    // the canonical type for a newly-built type.
1683    New = new (*this, TypeAlignment)
1684      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
1685                                  SizeExpr, AttrLoc);
1686  } else {
1687    QualType CanonVecTy = getCanonicalType(vecType);
1688    if (CanonVecTy == vecType) {
1689      New = new (*this, TypeAlignment)
1690        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
1691                                    AttrLoc);
1692
1693      DependentSizedExtVectorType *CanonCheck
1694        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1695      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
1696      (void)CanonCheck;
1697      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
1698    } else {
1699      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
1700                                                      SourceLocation());
1701      New = new (*this, TypeAlignment)
1702        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
1703    }
1704  }
1705
1706  Types.push_back(New);
1707  return QualType(New, 0);
1708}
1709
1710/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
1711///
1712QualType ASTContext::getFunctionNoProtoType(QualType ResultTy,
1713                                            const FunctionType::ExtInfo &Info) {
1714  const CallingConv CallConv = Info.getCC();
1715  // Unique functions, to guarantee there is only one function of a particular
1716  // structure.
1717  llvm::FoldingSetNodeID ID;
1718  FunctionNoProtoType::Profile(ID, ResultTy, Info);
1719
1720  void *InsertPos = 0;
1721  if (FunctionNoProtoType *FT =
1722        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1723    return QualType(FT, 0);
1724
1725  QualType Canonical;
1726  if (!ResultTy.isCanonical() ||
1727      getCanonicalCallConv(CallConv) != CallConv) {
1728    Canonical =
1729      getFunctionNoProtoType(getCanonicalType(ResultTy),
1730                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1731
1732    // Get the new insert position for the node we care about.
1733    FunctionNoProtoType *NewIP =
1734      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1735    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1736  }
1737
1738  FunctionNoProtoType *New = new (*this, TypeAlignment)
1739    FunctionNoProtoType(ResultTy, Canonical, Info);
1740  Types.push_back(New);
1741  FunctionNoProtoTypes.InsertNode(New, InsertPos);
1742  return QualType(New, 0);
1743}
1744
1745/// getFunctionType - Return a normal function type with a typed argument
1746/// list.  isVariadic indicates whether the argument list includes '...'.
1747QualType ASTContext::getFunctionType(QualType ResultTy,const QualType *ArgArray,
1748                                     unsigned NumArgs, bool isVariadic,
1749                                     unsigned TypeQuals, bool hasExceptionSpec,
1750                                     bool hasAnyExceptionSpec, unsigned NumExs,
1751                                     const QualType *ExArray,
1752                                     const FunctionType::ExtInfo &Info) {
1753
1754  const CallingConv CallConv= Info.getCC();
1755  // Unique functions, to guarantee there is only one function of a particular
1756  // structure.
1757  llvm::FoldingSetNodeID ID;
1758  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, isVariadic,
1759                             TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1760                             NumExs, ExArray, Info);
1761
1762  void *InsertPos = 0;
1763  if (FunctionProtoType *FTP =
1764        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1765    return QualType(FTP, 0);
1766
1767  // Determine whether the type being created is already canonical or not.
1768  bool isCanonical = !hasExceptionSpec && ResultTy.isCanonical();
1769  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
1770    if (!ArgArray[i].isCanonicalAsParam())
1771      isCanonical = false;
1772
1773  // If this type isn't canonical, get the canonical version of it.
1774  // The exception spec is not part of the canonical type.
1775  QualType Canonical;
1776  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
1777    llvm::SmallVector<QualType, 16> CanonicalArgs;
1778    CanonicalArgs.reserve(NumArgs);
1779    for (unsigned i = 0; i != NumArgs; ++i)
1780      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
1781
1782    Canonical = getFunctionType(getCanonicalType(ResultTy),
1783                                CanonicalArgs.data(), NumArgs,
1784                                isVariadic, TypeQuals, false,
1785                                false, 0, 0,
1786                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1787
1788    // Get the new insert position for the node we care about.
1789    FunctionProtoType *NewIP =
1790      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1791    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1792  }
1793
1794  // FunctionProtoType objects are allocated with extra bytes after them
1795  // for two variable size arrays (for parameter and exception types) at the
1796  // end of them.
1797  FunctionProtoType *FTP =
1798    (FunctionProtoType*)Allocate(sizeof(FunctionProtoType) +
1799                                 NumArgs*sizeof(QualType) +
1800                                 NumExs*sizeof(QualType), TypeAlignment);
1801  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, isVariadic,
1802                              TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1803                              ExArray, NumExs, Canonical, Info);
1804  Types.push_back(FTP);
1805  FunctionProtoTypes.InsertNode(FTP, InsertPos);
1806  return QualType(FTP, 0);
1807}
1808
1809#ifndef NDEBUG
1810static bool NeedsInjectedClassNameType(const RecordDecl *D) {
1811  if (!isa<CXXRecordDecl>(D)) return false;
1812  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
1813  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
1814    return true;
1815  if (RD->getDescribedClassTemplate() &&
1816      !isa<ClassTemplateSpecializationDecl>(RD))
1817    return true;
1818  return false;
1819}
1820#endif
1821
1822/// getInjectedClassNameType - Return the unique reference to the
1823/// injected class name type for the specified templated declaration.
1824QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
1825                                              QualType TST) {
1826  assert(NeedsInjectedClassNameType(Decl));
1827  if (Decl->TypeForDecl) {
1828    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1829  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDeclaration()) {
1830    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
1831    Decl->TypeForDecl = PrevDecl->TypeForDecl;
1832    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1833  } else {
1834    Decl->TypeForDecl =
1835      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
1836    Types.push_back(Decl->TypeForDecl);
1837  }
1838  return QualType(Decl->TypeForDecl, 0);
1839}
1840
1841/// getTypeDeclType - Return the unique reference to the type for the
1842/// specified type declaration.
1843QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) {
1844  assert(Decl && "Passed null for Decl param");
1845  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
1846
1847  if (const TypedefDecl *Typedef = dyn_cast<TypedefDecl>(Decl))
1848    return getTypedefType(Typedef);
1849
1850  assert(!isa<TemplateTypeParmDecl>(Decl) &&
1851         "Template type parameter types are always available.");
1852
1853  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
1854    assert(!Record->getPreviousDeclaration() &&
1855           "struct/union has previous declaration");
1856    assert(!NeedsInjectedClassNameType(Record));
1857    return getRecordType(Record);
1858  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
1859    assert(!Enum->getPreviousDeclaration() &&
1860           "enum has previous declaration");
1861    return getEnumType(Enum);
1862  } else if (const UnresolvedUsingTypenameDecl *Using =
1863               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
1864    Decl->TypeForDecl = new (*this, TypeAlignment) UnresolvedUsingType(Using);
1865  } else
1866    llvm_unreachable("TypeDecl without a type?");
1867
1868  Types.push_back(Decl->TypeForDecl);
1869  return QualType(Decl->TypeForDecl, 0);
1870}
1871
1872/// getTypedefType - Return the unique reference to the type for the
1873/// specified typename decl.
1874QualType
1875ASTContext::getTypedefType(const TypedefDecl *Decl, QualType Canonical) {
1876  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1877
1878  if (Canonical.isNull())
1879    Canonical = getCanonicalType(Decl->getUnderlyingType());
1880  Decl->TypeForDecl = new(*this, TypeAlignment)
1881    TypedefType(Type::Typedef, Decl, Canonical);
1882  Types.push_back(Decl->TypeForDecl);
1883  return QualType(Decl->TypeForDecl, 0);
1884}
1885
1886QualType ASTContext::getRecordType(const RecordDecl *Decl) {
1887  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1888
1889  if (const RecordDecl *PrevDecl = Decl->getPreviousDeclaration())
1890    if (PrevDecl->TypeForDecl)
1891      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1892
1893  Decl->TypeForDecl = new (*this, TypeAlignment) RecordType(Decl);
1894  Types.push_back(Decl->TypeForDecl);
1895  return QualType(Decl->TypeForDecl, 0);
1896}
1897
1898QualType ASTContext::getEnumType(const EnumDecl *Decl) {
1899  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1900
1901  if (const EnumDecl *PrevDecl = Decl->getPreviousDeclaration())
1902    if (PrevDecl->TypeForDecl)
1903      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1904
1905  Decl->TypeForDecl = new (*this, TypeAlignment) EnumType(Decl);
1906  Types.push_back(Decl->TypeForDecl);
1907  return QualType(Decl->TypeForDecl, 0);
1908}
1909
1910/// \brief Retrieve a substitution-result type.
1911QualType
1912ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
1913                                         QualType Replacement) {
1914  assert(Replacement.isCanonical()
1915         && "replacement types must always be canonical");
1916
1917  llvm::FoldingSetNodeID ID;
1918  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
1919  void *InsertPos = 0;
1920  SubstTemplateTypeParmType *SubstParm
1921    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1922
1923  if (!SubstParm) {
1924    SubstParm = new (*this, TypeAlignment)
1925      SubstTemplateTypeParmType(Parm, Replacement);
1926    Types.push_back(SubstParm);
1927    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
1928  }
1929
1930  return QualType(SubstParm, 0);
1931}
1932
1933/// \brief Retrieve the template type parameter type for a template
1934/// parameter or parameter pack with the given depth, index, and (optionally)
1935/// name.
1936QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
1937                                             bool ParameterPack,
1938                                             IdentifierInfo *Name) {
1939  llvm::FoldingSetNodeID ID;
1940  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, Name);
1941  void *InsertPos = 0;
1942  TemplateTypeParmType *TypeParm
1943    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1944
1945  if (TypeParm)
1946    return QualType(TypeParm, 0);
1947
1948  if (Name) {
1949    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
1950    TypeParm = new (*this, TypeAlignment)
1951      TemplateTypeParmType(Depth, Index, ParameterPack, Name, Canon);
1952
1953    TemplateTypeParmType *TypeCheck
1954      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1955    assert(!TypeCheck && "Template type parameter canonical type broken");
1956    (void)TypeCheck;
1957  } else
1958    TypeParm = new (*this, TypeAlignment)
1959      TemplateTypeParmType(Depth, Index, ParameterPack);
1960
1961  Types.push_back(TypeParm);
1962  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
1963
1964  return QualType(TypeParm, 0);
1965}
1966
1967TypeSourceInfo *
1968ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
1969                                              SourceLocation NameLoc,
1970                                        const TemplateArgumentListInfo &Args,
1971                                              QualType CanonType) {
1972  QualType TST = getTemplateSpecializationType(Name, Args, CanonType);
1973
1974  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
1975  TemplateSpecializationTypeLoc TL
1976    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
1977  TL.setTemplateNameLoc(NameLoc);
1978  TL.setLAngleLoc(Args.getLAngleLoc());
1979  TL.setRAngleLoc(Args.getRAngleLoc());
1980  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
1981    TL.setArgLocInfo(i, Args[i].getLocInfo());
1982  return DI;
1983}
1984
1985QualType
1986ASTContext::getTemplateSpecializationType(TemplateName Template,
1987                                          const TemplateArgumentListInfo &Args,
1988                                          QualType Canon) {
1989  unsigned NumArgs = Args.size();
1990
1991  llvm::SmallVector<TemplateArgument, 4> ArgVec;
1992  ArgVec.reserve(NumArgs);
1993  for (unsigned i = 0; i != NumArgs; ++i)
1994    ArgVec.push_back(Args[i].getArgument());
1995
1996  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
1997                                       Canon);
1998}
1999
2000QualType
2001ASTContext::getTemplateSpecializationType(TemplateName Template,
2002                                          const TemplateArgument *Args,
2003                                          unsigned NumArgs,
2004                                          QualType Canon) {
2005  if (!Canon.isNull())
2006    Canon = getCanonicalType(Canon);
2007  else
2008    Canon = getCanonicalTemplateSpecializationType(Template, Args, NumArgs);
2009
2010  // Allocate the (non-canonical) template specialization type, but don't
2011  // try to unique it: these types typically have location information that
2012  // we don't unique and don't want to lose.
2013  void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2014                        sizeof(TemplateArgument) * NumArgs),
2015                       TypeAlignment);
2016  TemplateSpecializationType *Spec
2017    = new (Mem) TemplateSpecializationType(Template,
2018                                           Args, NumArgs,
2019                                           Canon);
2020
2021  Types.push_back(Spec);
2022  return QualType(Spec, 0);
2023}
2024
2025QualType
2026ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
2027                                                   const TemplateArgument *Args,
2028                                                   unsigned NumArgs) {
2029  // Build the canonical template specialization type.
2030  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
2031  llvm::SmallVector<TemplateArgument, 4> CanonArgs;
2032  CanonArgs.reserve(NumArgs);
2033  for (unsigned I = 0; I != NumArgs; ++I)
2034    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
2035
2036  // Determine whether this canonical template specialization type already
2037  // exists.
2038  llvm::FoldingSetNodeID ID;
2039  TemplateSpecializationType::Profile(ID, CanonTemplate,
2040                                      CanonArgs.data(), NumArgs, *this);
2041
2042  void *InsertPos = 0;
2043  TemplateSpecializationType *Spec
2044    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2045
2046  if (!Spec) {
2047    // Allocate a new canonical template specialization type.
2048    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2049                          sizeof(TemplateArgument) * NumArgs),
2050                         TypeAlignment);
2051    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
2052                                                CanonArgs.data(), NumArgs,
2053                                                QualType());
2054    Types.push_back(Spec);
2055    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
2056  }
2057
2058  assert(Spec->isDependentType() &&
2059         "Non-dependent template-id type must have a canonical type");
2060  return QualType(Spec, 0);
2061}
2062
2063QualType
2064ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
2065                              NestedNameSpecifier *NNS,
2066                              QualType NamedType) {
2067  llvm::FoldingSetNodeID ID;
2068  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2069
2070  void *InsertPos = 0;
2071  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2072  if (T)
2073    return QualType(T, 0);
2074
2075  QualType Canon = NamedType;
2076  if (!Canon.isCanonical()) {
2077    Canon = getCanonicalType(NamedType);
2078    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2079    assert(!CheckT && "Elaborated canonical type broken");
2080    (void)CheckT;
2081  }
2082
2083  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2084  Types.push_back(T);
2085  ElaboratedTypes.InsertNode(T, InsertPos);
2086  return QualType(T, 0);
2087}
2088
2089QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2090                                          NestedNameSpecifier *NNS,
2091                                          const IdentifierInfo *Name,
2092                                          QualType Canon) {
2093  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2094
2095  if (Canon.isNull()) {
2096    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2097    ElaboratedTypeKeyword CanonKeyword = Keyword;
2098    if (Keyword == ETK_None)
2099      CanonKeyword = ETK_Typename;
2100
2101    if (CanonNNS != NNS || CanonKeyword != Keyword)
2102      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2103  }
2104
2105  llvm::FoldingSetNodeID ID;
2106  DependentNameType::Profile(ID, Keyword, NNS, Name);
2107
2108  void *InsertPos = 0;
2109  DependentNameType *T
2110    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2111  if (T)
2112    return QualType(T, 0);
2113
2114  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2115  Types.push_back(T);
2116  DependentNameTypes.InsertNode(T, InsertPos);
2117  return QualType(T, 0);
2118}
2119
2120QualType
2121ASTContext::getDependentTemplateSpecializationType(
2122                                 ElaboratedTypeKeyword Keyword,
2123                                 NestedNameSpecifier *NNS,
2124                                 const IdentifierInfo *Name,
2125                                 const TemplateArgumentListInfo &Args) {
2126  // TODO: avoid this copy
2127  llvm::SmallVector<TemplateArgument, 16> ArgCopy;
2128  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2129    ArgCopy.push_back(Args[I].getArgument());
2130  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2131                                                ArgCopy.size(),
2132                                                ArgCopy.data());
2133}
2134
2135QualType
2136ASTContext::getDependentTemplateSpecializationType(
2137                                 ElaboratedTypeKeyword Keyword,
2138                                 NestedNameSpecifier *NNS,
2139                                 const IdentifierInfo *Name,
2140                                 unsigned NumArgs,
2141                                 const TemplateArgument *Args) {
2142  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2143
2144  llvm::FoldingSetNodeID ID;
2145  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2146                                               Name, NumArgs, Args);
2147
2148  void *InsertPos = 0;
2149  DependentTemplateSpecializationType *T
2150    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2151  if (T)
2152    return QualType(T, 0);
2153
2154  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2155
2156  ElaboratedTypeKeyword CanonKeyword = Keyword;
2157  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2158
2159  bool AnyNonCanonArgs = false;
2160  llvm::SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2161  for (unsigned I = 0; I != NumArgs; ++I) {
2162    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2163    if (!CanonArgs[I].structurallyEquals(Args[I]))
2164      AnyNonCanonArgs = true;
2165  }
2166
2167  QualType Canon;
2168  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2169    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2170                                                   Name, NumArgs,
2171                                                   CanonArgs.data());
2172
2173    // Find the insert position again.
2174    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2175  }
2176
2177  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2178                        sizeof(TemplateArgument) * NumArgs),
2179                       TypeAlignment);
2180  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2181                                                    Name, NumArgs, Args, Canon);
2182  Types.push_back(T);
2183  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2184  return QualType(T, 0);
2185}
2186
2187/// CmpProtocolNames - Comparison predicate for sorting protocols
2188/// alphabetically.
2189static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2190                            const ObjCProtocolDecl *RHS) {
2191  return LHS->getDeclName() < RHS->getDeclName();
2192}
2193
2194static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2195                                unsigned NumProtocols) {
2196  if (NumProtocols == 0) return true;
2197
2198  for (unsigned i = 1; i != NumProtocols; ++i)
2199    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]))
2200      return false;
2201  return true;
2202}
2203
2204static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2205                                   unsigned &NumProtocols) {
2206  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2207
2208  // Sort protocols, keyed by name.
2209  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2210
2211  // Remove duplicates.
2212  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2213  NumProtocols = ProtocolsEnd-Protocols;
2214}
2215
2216QualType ASTContext::getObjCObjectType(QualType BaseType,
2217                                       ObjCProtocolDecl * const *Protocols,
2218                                       unsigned NumProtocols) {
2219  // If the base type is an interface and there aren't any protocols
2220  // to add, then the interface type will do just fine.
2221  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2222    return BaseType;
2223
2224  // Look in the folding set for an existing type.
2225  llvm::FoldingSetNodeID ID;
2226  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2227  void *InsertPos = 0;
2228  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2229    return QualType(QT, 0);
2230
2231  // Build the canonical type, which has the canonical base type and
2232  // a sorted-and-uniqued list of protocols.
2233  QualType Canonical;
2234  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2235  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2236    if (!ProtocolsSorted) {
2237      llvm::SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2238                                                     Protocols + NumProtocols);
2239      unsigned UniqueCount = NumProtocols;
2240
2241      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2242      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2243                                    &Sorted[0], UniqueCount);
2244    } else {
2245      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2246                                    Protocols, NumProtocols);
2247    }
2248
2249    // Regenerate InsertPos.
2250    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2251  }
2252
2253  unsigned Size = sizeof(ObjCObjectTypeImpl);
2254  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2255  void *Mem = Allocate(Size, TypeAlignment);
2256  ObjCObjectTypeImpl *T =
2257    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2258
2259  Types.push_back(T);
2260  ObjCObjectTypes.InsertNode(T, InsertPos);
2261  return QualType(T, 0);
2262}
2263
2264/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2265/// the given object type.
2266QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) {
2267  llvm::FoldingSetNodeID ID;
2268  ObjCObjectPointerType::Profile(ID, ObjectT);
2269
2270  void *InsertPos = 0;
2271  if (ObjCObjectPointerType *QT =
2272              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2273    return QualType(QT, 0);
2274
2275  // Find the canonical object type.
2276  QualType Canonical;
2277  if (!ObjectT.isCanonical()) {
2278    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2279
2280    // Regenerate InsertPos.
2281    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2282  }
2283
2284  // No match.
2285  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2286  ObjCObjectPointerType *QType =
2287    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2288
2289  Types.push_back(QType);
2290  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2291  return QualType(QType, 0);
2292}
2293
2294/// getObjCInterfaceType - Return the unique reference to the type for the
2295/// specified ObjC interface decl. The list of protocols is optional.
2296QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl) {
2297  if (Decl->TypeForDecl)
2298    return QualType(Decl->TypeForDecl, 0);
2299
2300  // FIXME: redeclarations?
2301  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2302  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2303  Decl->TypeForDecl = T;
2304  Types.push_back(T);
2305  return QualType(T, 0);
2306}
2307
2308/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2309/// TypeOfExprType AST's (since expression's are never shared). For example,
2310/// multiple declarations that refer to "typeof(x)" all contain different
2311/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2312/// on canonical type's (which are always unique).
2313QualType ASTContext::getTypeOfExprType(Expr *tofExpr) {
2314  TypeOfExprType *toe;
2315  if (tofExpr->isTypeDependent()) {
2316    llvm::FoldingSetNodeID ID;
2317    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2318
2319    void *InsertPos = 0;
2320    DependentTypeOfExprType *Canon
2321      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2322    if (Canon) {
2323      // We already have a "canonical" version of an identical, dependent
2324      // typeof(expr) type. Use that as our canonical type.
2325      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2326                                          QualType((TypeOfExprType*)Canon, 0));
2327    }
2328    else {
2329      // Build a new, canonical typeof(expr) type.
2330      Canon
2331        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2332      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2333      toe = Canon;
2334    }
2335  } else {
2336    QualType Canonical = getCanonicalType(tofExpr->getType());
2337    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2338  }
2339  Types.push_back(toe);
2340  return QualType(toe, 0);
2341}
2342
2343/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2344/// TypeOfType AST's. The only motivation to unique these nodes would be
2345/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2346/// an issue. This doesn't effect the type checker, since it operates
2347/// on canonical type's (which are always unique).
2348QualType ASTContext::getTypeOfType(QualType tofType) {
2349  QualType Canonical = getCanonicalType(tofType);
2350  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2351  Types.push_back(tot);
2352  return QualType(tot, 0);
2353}
2354
2355/// getDecltypeForExpr - Given an expr, will return the decltype for that
2356/// expression, according to the rules in C++0x [dcl.type.simple]p4
2357static QualType getDecltypeForExpr(const Expr *e, ASTContext &Context) {
2358  if (e->isTypeDependent())
2359    return Context.DependentTy;
2360
2361  // If e is an id expression or a class member access, decltype(e) is defined
2362  // as the type of the entity named by e.
2363  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2364    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2365      return VD->getType();
2366  }
2367  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2368    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2369      return FD->getType();
2370  }
2371  // If e is a function call or an invocation of an overloaded operator,
2372  // (parentheses around e are ignored), decltype(e) is defined as the
2373  // return type of that function.
2374  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2375    return CE->getCallReturnType();
2376
2377  QualType T = e->getType();
2378
2379  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2380  // defined as T&, otherwise decltype(e) is defined as T.
2381  if (e->isLValue())
2382    T = Context.getLValueReferenceType(T);
2383
2384  return T;
2385}
2386
2387/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2388/// DecltypeType AST's. The only motivation to unique these nodes would be
2389/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2390/// an issue. This doesn't effect the type checker, since it operates
2391/// on canonical type's (which are always unique).
2392QualType ASTContext::getDecltypeType(Expr *e) {
2393  DecltypeType *dt;
2394  if (e->isTypeDependent()) {
2395    llvm::FoldingSetNodeID ID;
2396    DependentDecltypeType::Profile(ID, *this, e);
2397
2398    void *InsertPos = 0;
2399    DependentDecltypeType *Canon
2400      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2401    if (Canon) {
2402      // We already have a "canonical" version of an equivalent, dependent
2403      // decltype type. Use that as our canonical type.
2404      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2405                                       QualType((DecltypeType*)Canon, 0));
2406    }
2407    else {
2408      // Build a new, canonical typeof(expr) type.
2409      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2410      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2411      dt = Canon;
2412    }
2413  } else {
2414    QualType T = getDecltypeForExpr(e, *this);
2415    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2416  }
2417  Types.push_back(dt);
2418  return QualType(dt, 0);
2419}
2420
2421/// getTagDeclType - Return the unique reference to the type for the
2422/// specified TagDecl (struct/union/class/enum) decl.
2423QualType ASTContext::getTagDeclType(const TagDecl *Decl) {
2424  assert (Decl);
2425  // FIXME: What is the design on getTagDeclType when it requires casting
2426  // away const?  mutable?
2427  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2428}
2429
2430/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2431/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2432/// needs to agree with the definition in <stddef.h>.
2433CanQualType ASTContext::getSizeType() const {
2434  return getFromTargetType(Target.getSizeType());
2435}
2436
2437/// getSignedWCharType - Return the type of "signed wchar_t".
2438/// Used when in C++, as a GCC extension.
2439QualType ASTContext::getSignedWCharType() const {
2440  // FIXME: derive from "Target" ?
2441  return WCharTy;
2442}
2443
2444/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
2445/// Used when in C++, as a GCC extension.
2446QualType ASTContext::getUnsignedWCharType() const {
2447  // FIXME: derive from "Target" ?
2448  return UnsignedIntTy;
2449}
2450
2451/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
2452/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
2453QualType ASTContext::getPointerDiffType() const {
2454  return getFromTargetType(Target.getPtrDiffType(0));
2455}
2456
2457//===----------------------------------------------------------------------===//
2458//                              Type Operators
2459//===----------------------------------------------------------------------===//
2460
2461CanQualType ASTContext::getCanonicalParamType(QualType T) {
2462  // Push qualifiers into arrays, and then discard any remaining
2463  // qualifiers.
2464  T = getCanonicalType(T);
2465  T = getVariableArrayDecayedType(T);
2466  const Type *Ty = T.getTypePtr();
2467  QualType Result;
2468  if (isa<ArrayType>(Ty)) {
2469    Result = getArrayDecayedType(QualType(Ty,0));
2470  } else if (isa<FunctionType>(Ty)) {
2471    Result = getPointerType(QualType(Ty, 0));
2472  } else {
2473    Result = QualType(Ty, 0);
2474  }
2475
2476  return CanQualType::CreateUnsafe(Result);
2477}
2478
2479/// getCanonicalType - Return the canonical (structural) type corresponding to
2480/// the specified potentially non-canonical type.  The non-canonical version
2481/// of a type may have many "decorated" versions of types.  Decorators can
2482/// include typedefs, 'typeof' operators, etc. The returned type is guaranteed
2483/// to be free of any of these, allowing two canonical types to be compared
2484/// for exact equality with a simple pointer comparison.
2485CanQualType ASTContext::getCanonicalType(QualType T) {
2486  QualifierCollector Quals;
2487  const Type *Ptr = Quals.strip(T);
2488  QualType CanType = Ptr->getCanonicalTypeInternal();
2489
2490  // The canonical internal type will be the canonical type *except*
2491  // that we push type qualifiers down through array types.
2492
2493  // If there are no new qualifiers to push down, stop here.
2494  if (!Quals.hasQualifiers())
2495    return CanQualType::CreateUnsafe(CanType);
2496
2497  // If the type qualifiers are on an array type, get the canonical
2498  // type of the array with the qualifiers applied to the element
2499  // type.
2500  ArrayType *AT = dyn_cast<ArrayType>(CanType);
2501  if (!AT)
2502    return CanQualType::CreateUnsafe(getQualifiedType(CanType, Quals));
2503
2504  // Get the canonical version of the element with the extra qualifiers on it.
2505  // This can recursively sink qualifiers through multiple levels of arrays.
2506  QualType NewEltTy = getQualifiedType(AT->getElementType(), Quals);
2507  NewEltTy = getCanonicalType(NewEltTy);
2508
2509  if (ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
2510    return CanQualType::CreateUnsafe(
2511             getConstantArrayType(NewEltTy, CAT->getSize(),
2512                                  CAT->getSizeModifier(),
2513                                  CAT->getIndexTypeCVRQualifiers()));
2514  if (IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT))
2515    return CanQualType::CreateUnsafe(
2516             getIncompleteArrayType(NewEltTy, IAT->getSizeModifier(),
2517                                    IAT->getIndexTypeCVRQualifiers()));
2518
2519  if (DependentSizedArrayType *DSAT = dyn_cast<DependentSizedArrayType>(AT))
2520    return CanQualType::CreateUnsafe(
2521             getDependentSizedArrayType(NewEltTy,
2522                                        DSAT->getSizeExpr(),
2523                                        DSAT->getSizeModifier(),
2524                                        DSAT->getIndexTypeCVRQualifiers(),
2525                        DSAT->getBracketsRange())->getCanonicalTypeInternal());
2526
2527  VariableArrayType *VAT = cast<VariableArrayType>(AT);
2528  return CanQualType::CreateUnsafe(getVariableArrayType(NewEltTy,
2529                                                        VAT->getSizeExpr(),
2530                                                        VAT->getSizeModifier(),
2531                                              VAT->getIndexTypeCVRQualifiers(),
2532                                                     VAT->getBracketsRange()));
2533}
2534
2535QualType ASTContext::getUnqualifiedArrayType(QualType T,
2536                                             Qualifiers &Quals) {
2537  Quals = T.getQualifiers();
2538  const ArrayType *AT = getAsArrayType(T);
2539  if (!AT) {
2540    return T.getUnqualifiedType();
2541  }
2542
2543  QualType Elt = AT->getElementType();
2544  QualType UnqualElt = getUnqualifiedArrayType(Elt, Quals);
2545  if (Elt == UnqualElt)
2546    return T;
2547
2548  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
2549    return getConstantArrayType(UnqualElt, CAT->getSize(),
2550                                CAT->getSizeModifier(), 0);
2551  }
2552
2553  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
2554    return getIncompleteArrayType(UnqualElt, IAT->getSizeModifier(), 0);
2555  }
2556
2557  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
2558    return getVariableArrayType(UnqualElt,
2559                                VAT->getSizeExpr(),
2560                                VAT->getSizeModifier(),
2561                                VAT->getIndexTypeCVRQualifiers(),
2562                                VAT->getBracketsRange());
2563  }
2564
2565  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
2566  return getDependentSizedArrayType(UnqualElt, DSAT->getSizeExpr(),
2567                                    DSAT->getSizeModifier(), 0,
2568                                    SourceRange());
2569}
2570
2571/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
2572/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
2573/// they point to and return true. If T1 and T2 aren't pointer types
2574/// or pointer-to-member types, or if they are not similar at this
2575/// level, returns false and leaves T1 and T2 unchanged. Top-level
2576/// qualifiers on T1 and T2 are ignored. This function will typically
2577/// be called in a loop that successively "unwraps" pointer and
2578/// pointer-to-member types to compare them at each level.
2579bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
2580  const PointerType *T1PtrType = T1->getAs<PointerType>(),
2581                    *T2PtrType = T2->getAs<PointerType>();
2582  if (T1PtrType && T2PtrType) {
2583    T1 = T1PtrType->getPointeeType();
2584    T2 = T2PtrType->getPointeeType();
2585    return true;
2586  }
2587
2588  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
2589                          *T2MPType = T2->getAs<MemberPointerType>();
2590  if (T1MPType && T2MPType &&
2591      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
2592                             QualType(T2MPType->getClass(), 0))) {
2593    T1 = T1MPType->getPointeeType();
2594    T2 = T2MPType->getPointeeType();
2595    return true;
2596  }
2597
2598  if (getLangOptions().ObjC1) {
2599    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
2600                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
2601    if (T1OPType && T2OPType) {
2602      T1 = T1OPType->getPointeeType();
2603      T2 = T2OPType->getPointeeType();
2604      return true;
2605    }
2606  }
2607
2608  // FIXME: Block pointers, too?
2609
2610  return false;
2611}
2612
2613DeclarationNameInfo ASTContext::getNameForTemplate(TemplateName Name,
2614                                                   SourceLocation NameLoc) {
2615  if (TemplateDecl *TD = Name.getAsTemplateDecl())
2616    // DNInfo work in progress: CHECKME: what about DNLoc?
2617    return DeclarationNameInfo(TD->getDeclName(), NameLoc);
2618
2619  if (DependentTemplateName *DTN = Name.getAsDependentTemplateName()) {
2620    DeclarationName DName;
2621    if (DTN->isIdentifier()) {
2622      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
2623      return DeclarationNameInfo(DName, NameLoc);
2624    } else {
2625      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
2626      // DNInfo work in progress: FIXME: source locations?
2627      DeclarationNameLoc DNLoc;
2628      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
2629      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
2630      return DeclarationNameInfo(DName, NameLoc, DNLoc);
2631    }
2632  }
2633
2634  OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
2635  assert(Storage);
2636  // DNInfo work in progress: CHECKME: what about DNLoc?
2637  return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
2638}
2639
2640TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) {
2641  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
2642    if (TemplateTemplateParmDecl *TTP
2643                              = dyn_cast<TemplateTemplateParmDecl>(Template))
2644      Template = getCanonicalTemplateTemplateParmDecl(TTP);
2645
2646    // The canonical template name is the canonical template declaration.
2647    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
2648  }
2649
2650  assert(!Name.getAsOverloadedTemplate());
2651
2652  DependentTemplateName *DTN = Name.getAsDependentTemplateName();
2653  assert(DTN && "Non-dependent template names must refer to template decls.");
2654  return DTN->CanonicalTemplateName;
2655}
2656
2657bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
2658  X = getCanonicalTemplateName(X);
2659  Y = getCanonicalTemplateName(Y);
2660  return X.getAsVoidPointer() == Y.getAsVoidPointer();
2661}
2662
2663TemplateArgument
2664ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) {
2665  switch (Arg.getKind()) {
2666    case TemplateArgument::Null:
2667      return Arg;
2668
2669    case TemplateArgument::Expression:
2670      return Arg;
2671
2672    case TemplateArgument::Declaration:
2673      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
2674
2675    case TemplateArgument::Template:
2676      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
2677
2678    case TemplateArgument::Integral:
2679      return TemplateArgument(*Arg.getAsIntegral(),
2680                              getCanonicalType(Arg.getIntegralType()));
2681
2682    case TemplateArgument::Type:
2683      return TemplateArgument(getCanonicalType(Arg.getAsType()));
2684
2685    case TemplateArgument::Pack: {
2686      TemplateArgument *CanonArgs
2687        = new (*this) TemplateArgument[Arg.pack_size()];
2688      unsigned Idx = 0;
2689      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
2690                                        AEnd = Arg.pack_end();
2691           A != AEnd; (void)++A, ++Idx)
2692        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
2693
2694      return TemplateArgument(CanonArgs, Arg.pack_size());
2695    }
2696  }
2697
2698  // Silence GCC warning
2699  assert(false && "Unhandled template argument kind");
2700  return TemplateArgument();
2701}
2702
2703NestedNameSpecifier *
2704ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) {
2705  if (!NNS)
2706    return 0;
2707
2708  switch (NNS->getKind()) {
2709  case NestedNameSpecifier::Identifier:
2710    // Canonicalize the prefix but keep the identifier the same.
2711    return NestedNameSpecifier::Create(*this,
2712                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
2713                                       NNS->getAsIdentifier());
2714
2715  case NestedNameSpecifier::Namespace:
2716    // A namespace is canonical; build a nested-name-specifier with
2717    // this namespace and no prefix.
2718    return NestedNameSpecifier::Create(*this, 0, NNS->getAsNamespace());
2719
2720  case NestedNameSpecifier::TypeSpec:
2721  case NestedNameSpecifier::TypeSpecWithTemplate: {
2722    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
2723
2724    // If we have some kind of dependent-named type (e.g., "typename T::type"),
2725    // break it apart into its prefix and identifier, then reconsititute those
2726    // as the canonical nested-name-specifier. This is required to canonicalize
2727    // a dependent nested-name-specifier involving typedefs of dependent-name
2728    // types, e.g.,
2729    //   typedef typename T::type T1;
2730    //   typedef typename T1::type T2;
2731    if (const DependentNameType *DNT = T->getAs<DependentNameType>()) {
2732      NestedNameSpecifier *Prefix
2733        = getCanonicalNestedNameSpecifier(DNT->getQualifier());
2734      return NestedNameSpecifier::Create(*this, Prefix,
2735                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
2736    }
2737
2738    // Do the same thing as above, but with dependent-named specializations.
2739    if (const DependentTemplateSpecializationType *DTST
2740          = T->getAs<DependentTemplateSpecializationType>()) {
2741      NestedNameSpecifier *Prefix
2742        = getCanonicalNestedNameSpecifier(DTST->getQualifier());
2743      TemplateName Name
2744        = getDependentTemplateName(Prefix, DTST->getIdentifier());
2745      T = getTemplateSpecializationType(Name,
2746                                        DTST->getArgs(), DTST->getNumArgs());
2747      T = getCanonicalType(T);
2748    }
2749
2750    return NestedNameSpecifier::Create(*this, 0, false, T.getTypePtr());
2751  }
2752
2753  case NestedNameSpecifier::Global:
2754    // The global specifier is canonical and unique.
2755    return NNS;
2756  }
2757
2758  // Required to silence a GCC warning
2759  return 0;
2760}
2761
2762
2763const ArrayType *ASTContext::getAsArrayType(QualType T) {
2764  // Handle the non-qualified case efficiently.
2765  if (!T.hasLocalQualifiers()) {
2766    // Handle the common positive case fast.
2767    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
2768      return AT;
2769  }
2770
2771  // Handle the common negative case fast.
2772  QualType CType = T->getCanonicalTypeInternal();
2773  if (!isa<ArrayType>(CType))
2774    return 0;
2775
2776  // Apply any qualifiers from the array type to the element type.  This
2777  // implements C99 6.7.3p8: "If the specification of an array type includes
2778  // any type qualifiers, the element type is so qualified, not the array type."
2779
2780  // If we get here, we either have type qualifiers on the type, or we have
2781  // sugar such as a typedef in the way.  If we have type qualifiers on the type
2782  // we must propagate them down into the element type.
2783
2784  QualifierCollector Qs;
2785  const Type *Ty = Qs.strip(T.getDesugaredType());
2786
2787  // If we have a simple case, just return now.
2788  const ArrayType *ATy = dyn_cast<ArrayType>(Ty);
2789  if (ATy == 0 || Qs.empty())
2790    return ATy;
2791
2792  // Otherwise, we have an array and we have qualifiers on it.  Push the
2793  // qualifiers into the array element type and return a new array type.
2794  // Get the canonical version of the element with the extra qualifiers on it.
2795  // This can recursively sink qualifiers through multiple levels of arrays.
2796  QualType NewEltTy = getQualifiedType(ATy->getElementType(), Qs);
2797
2798  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
2799    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
2800                                                CAT->getSizeModifier(),
2801                                           CAT->getIndexTypeCVRQualifiers()));
2802  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
2803    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
2804                                                  IAT->getSizeModifier(),
2805                                           IAT->getIndexTypeCVRQualifiers()));
2806
2807  if (const DependentSizedArrayType *DSAT
2808        = dyn_cast<DependentSizedArrayType>(ATy))
2809    return cast<ArrayType>(
2810                     getDependentSizedArrayType(NewEltTy,
2811                                                DSAT->getSizeExpr(),
2812                                                DSAT->getSizeModifier(),
2813                                              DSAT->getIndexTypeCVRQualifiers(),
2814                                                DSAT->getBracketsRange()));
2815
2816  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
2817  return cast<ArrayType>(getVariableArrayType(NewEltTy,
2818                                              VAT->getSizeExpr(),
2819                                              VAT->getSizeModifier(),
2820                                              VAT->getIndexTypeCVRQualifiers(),
2821                                              VAT->getBracketsRange()));
2822}
2823
2824/// getArrayDecayedType - Return the properly qualified result of decaying the
2825/// specified array type to a pointer.  This operation is non-trivial when
2826/// handling typedefs etc.  The canonical type of "T" must be an array type,
2827/// this returns a pointer to a properly qualified element of the array.
2828///
2829/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
2830QualType ASTContext::getArrayDecayedType(QualType Ty) {
2831  // Get the element type with 'getAsArrayType' so that we don't lose any
2832  // typedefs in the element type of the array.  This also handles propagation
2833  // of type qualifiers from the array type into the element type if present
2834  // (C99 6.7.3p8).
2835  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
2836  assert(PrettyArrayType && "Not an array type!");
2837
2838  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
2839
2840  // int x[restrict 4] ->  int *restrict
2841  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
2842}
2843
2844QualType ASTContext::getBaseElementType(QualType QT) {
2845  QualifierCollector Qs;
2846  while (const ArrayType *AT = getAsArrayType(QualType(Qs.strip(QT), 0)))
2847    QT = AT->getElementType();
2848  return Qs.apply(QT);
2849}
2850
2851QualType ASTContext::getBaseElementType(const ArrayType *AT) {
2852  QualType ElemTy = AT->getElementType();
2853
2854  if (const ArrayType *AT = getAsArrayType(ElemTy))
2855    return getBaseElementType(AT);
2856
2857  return ElemTy;
2858}
2859
2860/// getConstantArrayElementCount - Returns number of constant array elements.
2861uint64_t
2862ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
2863  uint64_t ElementCount = 1;
2864  do {
2865    ElementCount *= CA->getSize().getZExtValue();
2866    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
2867  } while (CA);
2868  return ElementCount;
2869}
2870
2871/// getFloatingRank - Return a relative rank for floating point types.
2872/// This routine will assert if passed a built-in type that isn't a float.
2873static FloatingRank getFloatingRank(QualType T) {
2874  if (const ComplexType *CT = T->getAs<ComplexType>())
2875    return getFloatingRank(CT->getElementType());
2876
2877  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
2878  switch (T->getAs<BuiltinType>()->getKind()) {
2879  default: assert(0 && "getFloatingRank(): not a floating type");
2880  case BuiltinType::Float:      return FloatRank;
2881  case BuiltinType::Double:     return DoubleRank;
2882  case BuiltinType::LongDouble: return LongDoubleRank;
2883  }
2884}
2885
2886/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
2887/// point or a complex type (based on typeDomain/typeSize).
2888/// 'typeDomain' is a real floating point or complex type.
2889/// 'typeSize' is a real floating point or complex type.
2890QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
2891                                                       QualType Domain) const {
2892  FloatingRank EltRank = getFloatingRank(Size);
2893  if (Domain->isComplexType()) {
2894    switch (EltRank) {
2895    default: assert(0 && "getFloatingRank(): illegal value for rank");
2896    case FloatRank:      return FloatComplexTy;
2897    case DoubleRank:     return DoubleComplexTy;
2898    case LongDoubleRank: return LongDoubleComplexTy;
2899    }
2900  }
2901
2902  assert(Domain->isRealFloatingType() && "Unknown domain!");
2903  switch (EltRank) {
2904  default: assert(0 && "getFloatingRank(): illegal value for rank");
2905  case FloatRank:      return FloatTy;
2906  case DoubleRank:     return DoubleTy;
2907  case LongDoubleRank: return LongDoubleTy;
2908  }
2909}
2910
2911/// getFloatingTypeOrder - Compare the rank of the two specified floating
2912/// point types, ignoring the domain of the type (i.e. 'double' ==
2913/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2914/// LHS < RHS, return -1.
2915int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) {
2916  FloatingRank LHSR = getFloatingRank(LHS);
2917  FloatingRank RHSR = getFloatingRank(RHS);
2918
2919  if (LHSR == RHSR)
2920    return 0;
2921  if (LHSR > RHSR)
2922    return 1;
2923  return -1;
2924}
2925
2926/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
2927/// routine will assert if passed a built-in type that isn't an integer or enum,
2928/// or if it is not canonicalized.
2929unsigned ASTContext::getIntegerRank(Type *T) {
2930  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
2931  if (EnumType* ET = dyn_cast<EnumType>(T))
2932    T = ET->getDecl()->getPromotionType().getTypePtr();
2933
2934  if (T->isSpecificBuiltinType(BuiltinType::WChar))
2935    T = getFromTargetType(Target.getWCharType()).getTypePtr();
2936
2937  if (T->isSpecificBuiltinType(BuiltinType::Char16))
2938    T = getFromTargetType(Target.getChar16Type()).getTypePtr();
2939
2940  if (T->isSpecificBuiltinType(BuiltinType::Char32))
2941    T = getFromTargetType(Target.getChar32Type()).getTypePtr();
2942
2943  switch (cast<BuiltinType>(T)->getKind()) {
2944  default: assert(0 && "getIntegerRank(): not a built-in integer");
2945  case BuiltinType::Bool:
2946    return 1 + (getIntWidth(BoolTy) << 3);
2947  case BuiltinType::Char_S:
2948  case BuiltinType::Char_U:
2949  case BuiltinType::SChar:
2950  case BuiltinType::UChar:
2951    return 2 + (getIntWidth(CharTy) << 3);
2952  case BuiltinType::Short:
2953  case BuiltinType::UShort:
2954    return 3 + (getIntWidth(ShortTy) << 3);
2955  case BuiltinType::Int:
2956  case BuiltinType::UInt:
2957    return 4 + (getIntWidth(IntTy) << 3);
2958  case BuiltinType::Long:
2959  case BuiltinType::ULong:
2960    return 5 + (getIntWidth(LongTy) << 3);
2961  case BuiltinType::LongLong:
2962  case BuiltinType::ULongLong:
2963    return 6 + (getIntWidth(LongLongTy) << 3);
2964  case BuiltinType::Int128:
2965  case BuiltinType::UInt128:
2966    return 7 + (getIntWidth(Int128Ty) << 3);
2967  }
2968}
2969
2970/// \brief Whether this is a promotable bitfield reference according
2971/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
2972///
2973/// \returns the type this bit-field will promote to, or NULL if no
2974/// promotion occurs.
2975QualType ASTContext::isPromotableBitField(Expr *E) {
2976  if (E->isTypeDependent() || E->isValueDependent())
2977    return QualType();
2978
2979  FieldDecl *Field = E->getBitField();
2980  if (!Field)
2981    return QualType();
2982
2983  QualType FT = Field->getType();
2984
2985  llvm::APSInt BitWidthAP = Field->getBitWidth()->EvaluateAsInt(*this);
2986  uint64_t BitWidth = BitWidthAP.getZExtValue();
2987  uint64_t IntSize = getTypeSize(IntTy);
2988  // GCC extension compatibility: if the bit-field size is less than or equal
2989  // to the size of int, it gets promoted no matter what its type is.
2990  // For instance, unsigned long bf : 4 gets promoted to signed int.
2991  if (BitWidth < IntSize)
2992    return IntTy;
2993
2994  if (BitWidth == IntSize)
2995    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
2996
2997  // Types bigger than int are not subject to promotions, and therefore act
2998  // like the base type.
2999  // FIXME: This doesn't quite match what gcc does, but what gcc does here
3000  // is ridiculous.
3001  return QualType();
3002}
3003
3004/// getPromotedIntegerType - Returns the type that Promotable will
3005/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
3006/// integer type.
3007QualType ASTContext::getPromotedIntegerType(QualType Promotable) {
3008  assert(!Promotable.isNull());
3009  assert(Promotable->isPromotableIntegerType());
3010  if (const EnumType *ET = Promotable->getAs<EnumType>())
3011    return ET->getDecl()->getPromotionType();
3012  if (Promotable->isSignedIntegerType())
3013    return IntTy;
3014  uint64_t PromotableSize = getTypeSize(Promotable);
3015  uint64_t IntSize = getTypeSize(IntTy);
3016  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3017  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3018}
3019
3020/// getIntegerTypeOrder - Returns the highest ranked integer type:
3021/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3022/// LHS < RHS, return -1.
3023int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) {
3024  Type *LHSC = getCanonicalType(LHS).getTypePtr();
3025  Type *RHSC = getCanonicalType(RHS).getTypePtr();
3026  if (LHSC == RHSC) return 0;
3027
3028  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3029  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3030
3031  unsigned LHSRank = getIntegerRank(LHSC);
3032  unsigned RHSRank = getIntegerRank(RHSC);
3033
3034  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3035    if (LHSRank == RHSRank) return 0;
3036    return LHSRank > RHSRank ? 1 : -1;
3037  }
3038
3039  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3040  if (LHSUnsigned) {
3041    // If the unsigned [LHS] type is larger, return it.
3042    if (LHSRank >= RHSRank)
3043      return 1;
3044
3045    // If the signed type can represent all values of the unsigned type, it
3046    // wins.  Because we are dealing with 2's complement and types that are
3047    // powers of two larger than each other, this is always safe.
3048    return -1;
3049  }
3050
3051  // If the unsigned [RHS] type is larger, return it.
3052  if (RHSRank >= LHSRank)
3053    return -1;
3054
3055  // If the signed type can represent all values of the unsigned type, it
3056  // wins.  Because we are dealing with 2's complement and types that are
3057  // powers of two larger than each other, this is always safe.
3058  return 1;
3059}
3060
3061static RecordDecl *
3062CreateRecordDecl(ASTContext &Ctx, RecordDecl::TagKind TK, DeclContext *DC,
3063                 SourceLocation L, IdentifierInfo *Id) {
3064  if (Ctx.getLangOptions().CPlusPlus)
3065    return CXXRecordDecl::Create(Ctx, TK, DC, L, Id);
3066  else
3067    return RecordDecl::Create(Ctx, TK, DC, L, Id);
3068}
3069
3070// getCFConstantStringType - Return the type used for constant CFStrings.
3071QualType ASTContext::getCFConstantStringType() {
3072  if (!CFConstantStringTypeDecl) {
3073    CFConstantStringTypeDecl =
3074      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3075                       &Idents.get("NSConstantString"));
3076    CFConstantStringTypeDecl->startDefinition();
3077
3078    QualType FieldTypes[4];
3079
3080    // const int *isa;
3081    FieldTypes[0] = getPointerType(IntTy.withConst());
3082    // int flags;
3083    FieldTypes[1] = IntTy;
3084    // const char *str;
3085    FieldTypes[2] = getPointerType(CharTy.withConst());
3086    // long length;
3087    FieldTypes[3] = LongTy;
3088
3089    // Create fields
3090    for (unsigned i = 0; i < 4; ++i) {
3091      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3092                                           SourceLocation(), 0,
3093                                           FieldTypes[i], /*TInfo=*/0,
3094                                           /*BitWidth=*/0,
3095                                           /*Mutable=*/false);
3096      Field->setAccess(AS_public);
3097      CFConstantStringTypeDecl->addDecl(Field);
3098    }
3099
3100    CFConstantStringTypeDecl->completeDefinition();
3101  }
3102
3103  return getTagDeclType(CFConstantStringTypeDecl);
3104}
3105
3106void ASTContext::setCFConstantStringType(QualType T) {
3107  const RecordType *Rec = T->getAs<RecordType>();
3108  assert(Rec && "Invalid CFConstantStringType");
3109  CFConstantStringTypeDecl = Rec->getDecl();
3110}
3111
3112// getNSConstantStringType - Return the type used for constant NSStrings.
3113QualType ASTContext::getNSConstantStringType() {
3114  if (!NSConstantStringTypeDecl) {
3115    NSConstantStringTypeDecl =
3116    CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3117                     &Idents.get("__builtin_NSString"));
3118    NSConstantStringTypeDecl->startDefinition();
3119
3120    QualType FieldTypes[3];
3121
3122    // const int *isa;
3123    FieldTypes[0] = getPointerType(IntTy.withConst());
3124    // const char *str;
3125    FieldTypes[1] = getPointerType(CharTy.withConst());
3126    // unsigned int length;
3127    FieldTypes[2] = UnsignedIntTy;
3128
3129    // Create fields
3130    for (unsigned i = 0; i < 3; ++i) {
3131      FieldDecl *Field = FieldDecl::Create(*this, NSConstantStringTypeDecl,
3132                                           SourceLocation(), 0,
3133                                           FieldTypes[i], /*TInfo=*/0,
3134                                           /*BitWidth=*/0,
3135                                           /*Mutable=*/false);
3136      Field->setAccess(AS_public);
3137      NSConstantStringTypeDecl->addDecl(Field);
3138    }
3139
3140    NSConstantStringTypeDecl->completeDefinition();
3141  }
3142
3143  return getTagDeclType(NSConstantStringTypeDecl);
3144}
3145
3146void ASTContext::setNSConstantStringType(QualType T) {
3147  const RecordType *Rec = T->getAs<RecordType>();
3148  assert(Rec && "Invalid NSConstantStringType");
3149  NSConstantStringTypeDecl = Rec->getDecl();
3150}
3151
3152QualType ASTContext::getObjCFastEnumerationStateType() {
3153  if (!ObjCFastEnumerationStateTypeDecl) {
3154    ObjCFastEnumerationStateTypeDecl =
3155      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3156                       &Idents.get("__objcFastEnumerationState"));
3157    ObjCFastEnumerationStateTypeDecl->startDefinition();
3158
3159    QualType FieldTypes[] = {
3160      UnsignedLongTy,
3161      getPointerType(ObjCIdTypedefType),
3162      getPointerType(UnsignedLongTy),
3163      getConstantArrayType(UnsignedLongTy,
3164                           llvm::APInt(32, 5), ArrayType::Normal, 0)
3165    };
3166
3167    for (size_t i = 0; i < 4; ++i) {
3168      FieldDecl *Field = FieldDecl::Create(*this,
3169                                           ObjCFastEnumerationStateTypeDecl,
3170                                           SourceLocation(), 0,
3171                                           FieldTypes[i], /*TInfo=*/0,
3172                                           /*BitWidth=*/0,
3173                                           /*Mutable=*/false);
3174      Field->setAccess(AS_public);
3175      ObjCFastEnumerationStateTypeDecl->addDecl(Field);
3176    }
3177
3178    ObjCFastEnumerationStateTypeDecl->completeDefinition();
3179  }
3180
3181  return getTagDeclType(ObjCFastEnumerationStateTypeDecl);
3182}
3183
3184QualType ASTContext::getBlockDescriptorType() {
3185  if (BlockDescriptorType)
3186    return getTagDeclType(BlockDescriptorType);
3187
3188  RecordDecl *T;
3189  // FIXME: Needs the FlagAppleBlock bit.
3190  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3191                       &Idents.get("__block_descriptor"));
3192  T->startDefinition();
3193
3194  QualType FieldTypes[] = {
3195    UnsignedLongTy,
3196    UnsignedLongTy,
3197  };
3198
3199  const char *FieldNames[] = {
3200    "reserved",
3201    "Size"
3202  };
3203
3204  for (size_t i = 0; i < 2; ++i) {
3205    FieldDecl *Field = FieldDecl::Create(*this,
3206                                         T,
3207                                         SourceLocation(),
3208                                         &Idents.get(FieldNames[i]),
3209                                         FieldTypes[i], /*TInfo=*/0,
3210                                         /*BitWidth=*/0,
3211                                         /*Mutable=*/false);
3212    Field->setAccess(AS_public);
3213    T->addDecl(Field);
3214  }
3215
3216  T->completeDefinition();
3217
3218  BlockDescriptorType = T;
3219
3220  return getTagDeclType(BlockDescriptorType);
3221}
3222
3223void ASTContext::setBlockDescriptorType(QualType T) {
3224  const RecordType *Rec = T->getAs<RecordType>();
3225  assert(Rec && "Invalid BlockDescriptorType");
3226  BlockDescriptorType = Rec->getDecl();
3227}
3228
3229QualType ASTContext::getBlockDescriptorExtendedType() {
3230  if (BlockDescriptorExtendedType)
3231    return getTagDeclType(BlockDescriptorExtendedType);
3232
3233  RecordDecl *T;
3234  // FIXME: Needs the FlagAppleBlock bit.
3235  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3236                       &Idents.get("__block_descriptor_withcopydispose"));
3237  T->startDefinition();
3238
3239  QualType FieldTypes[] = {
3240    UnsignedLongTy,
3241    UnsignedLongTy,
3242    getPointerType(VoidPtrTy),
3243    getPointerType(VoidPtrTy)
3244  };
3245
3246  const char *FieldNames[] = {
3247    "reserved",
3248    "Size",
3249    "CopyFuncPtr",
3250    "DestroyFuncPtr"
3251  };
3252
3253  for (size_t i = 0; i < 4; ++i) {
3254    FieldDecl *Field = FieldDecl::Create(*this,
3255                                         T,
3256                                         SourceLocation(),
3257                                         &Idents.get(FieldNames[i]),
3258                                         FieldTypes[i], /*TInfo=*/0,
3259                                         /*BitWidth=*/0,
3260                                         /*Mutable=*/false);
3261    Field->setAccess(AS_public);
3262    T->addDecl(Field);
3263  }
3264
3265  T->completeDefinition();
3266
3267  BlockDescriptorExtendedType = T;
3268
3269  return getTagDeclType(BlockDescriptorExtendedType);
3270}
3271
3272void ASTContext::setBlockDescriptorExtendedType(QualType T) {
3273  const RecordType *Rec = T->getAs<RecordType>();
3274  assert(Rec && "Invalid BlockDescriptorType");
3275  BlockDescriptorExtendedType = Rec->getDecl();
3276}
3277
3278bool ASTContext::BlockRequiresCopying(QualType Ty) {
3279  if (Ty->isBlockPointerType())
3280    return true;
3281  if (isObjCNSObjectType(Ty))
3282    return true;
3283  if (Ty->isObjCObjectPointerType())
3284    return true;
3285  if (getLangOptions().CPlusPlus) {
3286    if (const RecordType *RT = Ty->getAs<RecordType>()) {
3287      CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
3288      return RD->hasConstCopyConstructor(*this);
3289
3290    }
3291  }
3292  return false;
3293}
3294
3295QualType ASTContext::BuildByRefType(llvm::StringRef DeclName, QualType Ty) {
3296  //  type = struct __Block_byref_1_X {
3297  //    void *__isa;
3298  //    struct __Block_byref_1_X *__forwarding;
3299  //    unsigned int __flags;
3300  //    unsigned int __size;
3301  //    void *__copy_helper;            // as needed
3302  //    void *__destroy_help            // as needed
3303  //    int X;
3304  //  } *
3305
3306  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3307
3308  // FIXME: Move up
3309  llvm::SmallString<36> Name;
3310  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3311                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3312  RecordDecl *T;
3313  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3314                       &Idents.get(Name.str()));
3315  T->startDefinition();
3316  QualType Int32Ty = IntTy;
3317  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3318  QualType FieldTypes[] = {
3319    getPointerType(VoidPtrTy),
3320    getPointerType(getTagDeclType(T)),
3321    Int32Ty,
3322    Int32Ty,
3323    getPointerType(VoidPtrTy),
3324    getPointerType(VoidPtrTy),
3325    Ty
3326  };
3327
3328  llvm::StringRef FieldNames[] = {
3329    "__isa",
3330    "__forwarding",
3331    "__flags",
3332    "__size",
3333    "__copy_helper",
3334    "__destroy_helper",
3335    DeclName,
3336  };
3337
3338  for (size_t i = 0; i < 7; ++i) {
3339    if (!HasCopyAndDispose && i >=4 && i <= 5)
3340      continue;
3341    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3342                                         &Idents.get(FieldNames[i]),
3343                                         FieldTypes[i], /*TInfo=*/0,
3344                                         /*BitWidth=*/0, /*Mutable=*/false);
3345    Field->setAccess(AS_public);
3346    T->addDecl(Field);
3347  }
3348
3349  T->completeDefinition();
3350
3351  return getPointerType(getTagDeclType(T));
3352}
3353
3354
3355QualType ASTContext::getBlockParmType(
3356  bool BlockHasCopyDispose,
3357  llvm::SmallVectorImpl<const Expr *> &Layout) {
3358
3359  // FIXME: Move up
3360  llvm::SmallString<36> Name;
3361  llvm::raw_svector_ostream(Name) << "__block_literal_"
3362                                  << ++UniqueBlockParmTypeID;
3363  RecordDecl *T;
3364  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3365                       &Idents.get(Name.str()));
3366  T->startDefinition();
3367  QualType FieldTypes[] = {
3368    getPointerType(VoidPtrTy),
3369    IntTy,
3370    IntTy,
3371    getPointerType(VoidPtrTy),
3372    (BlockHasCopyDispose ?
3373     getPointerType(getBlockDescriptorExtendedType()) :
3374     getPointerType(getBlockDescriptorType()))
3375  };
3376
3377  const char *FieldNames[] = {
3378    "__isa",
3379    "__flags",
3380    "__reserved",
3381    "__FuncPtr",
3382    "__descriptor"
3383  };
3384
3385  for (size_t i = 0; i < 5; ++i) {
3386    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3387                                         &Idents.get(FieldNames[i]),
3388                                         FieldTypes[i], /*TInfo=*/0,
3389                                         /*BitWidth=*/0, /*Mutable=*/false);
3390    Field->setAccess(AS_public);
3391    T->addDecl(Field);
3392  }
3393
3394  for (unsigned i = 0; i < Layout.size(); ++i) {
3395    const Expr *E = Layout[i];
3396
3397    QualType FieldType = E->getType();
3398    IdentifierInfo *FieldName = 0;
3399    if (isa<CXXThisExpr>(E)) {
3400      FieldName = &Idents.get("this");
3401    } else if (const BlockDeclRefExpr *BDRE = dyn_cast<BlockDeclRefExpr>(E)) {
3402      const ValueDecl *D = BDRE->getDecl();
3403      FieldName = D->getIdentifier();
3404      if (BDRE->isByRef())
3405        FieldType = BuildByRefType(D->getName(), FieldType);
3406    } else {
3407      // Padding.
3408      assert(isa<ConstantArrayType>(FieldType) &&
3409             isa<DeclRefExpr>(E) &&
3410             !cast<DeclRefExpr>(E)->getDecl()->getDeclName() &&
3411             "doesn't match characteristics of padding decl");
3412    }
3413
3414    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3415                                         FieldName, FieldType, /*TInfo=*/0,
3416                                         /*BitWidth=*/0, /*Mutable=*/false);
3417    Field->setAccess(AS_public);
3418    T->addDecl(Field);
3419  }
3420
3421  T->completeDefinition();
3422
3423  return getPointerType(getTagDeclType(T));
3424}
3425
3426void ASTContext::setObjCFastEnumerationStateType(QualType T) {
3427  const RecordType *Rec = T->getAs<RecordType>();
3428  assert(Rec && "Invalid ObjCFAstEnumerationStateType");
3429  ObjCFastEnumerationStateTypeDecl = Rec->getDecl();
3430}
3431
3432// This returns true if a type has been typedefed to BOOL:
3433// typedef <type> BOOL;
3434static bool isTypeTypedefedAsBOOL(QualType T) {
3435  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3436    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3437      return II->isStr("BOOL");
3438
3439  return false;
3440}
3441
3442/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3443/// purpose.
3444CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) {
3445  CharUnits sz = getTypeSizeInChars(type);
3446
3447  // Make all integer and enum types at least as large as an int
3448  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3449    sz = std::max(sz, getTypeSizeInChars(IntTy));
3450  // Treat arrays as pointers, since that's how they're passed in.
3451  else if (type->isArrayType())
3452    sz = getTypeSizeInChars(VoidPtrTy);
3453  return sz;
3454}
3455
3456static inline
3457std::string charUnitsToString(const CharUnits &CU) {
3458  return llvm::itostr(CU.getQuantity());
3459}
3460
3461/// getObjCEncodingForBlockDecl - Return the encoded type for this block
3462/// declaration.
3463void ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr,
3464                                             std::string& S) {
3465  const BlockDecl *Decl = Expr->getBlockDecl();
3466  QualType BlockTy =
3467      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3468  // Encode result type.
3469  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3470  // Compute size of all parameters.
3471  // Start with computing size of a pointer in number of bytes.
3472  // FIXME: There might(should) be a better way of doing this computation!
3473  SourceLocation Loc;
3474  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3475  CharUnits ParmOffset = PtrSize;
3476  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3477       E = Decl->param_end(); PI != E; ++PI) {
3478    QualType PType = (*PI)->getType();
3479    CharUnits sz = getObjCEncodingTypeSize(PType);
3480    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3481    ParmOffset += sz;
3482  }
3483  // Size of the argument frame
3484  S += charUnitsToString(ParmOffset);
3485  // Block pointer and offset.
3486  S += "@?0";
3487  ParmOffset = PtrSize;
3488
3489  // Argument types.
3490  ParmOffset = PtrSize;
3491  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3492       Decl->param_end(); PI != E; ++PI) {
3493    ParmVarDecl *PVDecl = *PI;
3494    QualType PType = PVDecl->getOriginalType();
3495    if (const ArrayType *AT =
3496          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3497      // Use array's original type only if it has known number of
3498      // elements.
3499      if (!isa<ConstantArrayType>(AT))
3500        PType = PVDecl->getType();
3501    } else if (PType->isFunctionType())
3502      PType = PVDecl->getType();
3503    getObjCEncodingForType(PType, S);
3504    S += charUnitsToString(ParmOffset);
3505    ParmOffset += getObjCEncodingTypeSize(PType);
3506  }
3507}
3508
3509/// getObjCEncodingForMethodDecl - Return the encoded type for this method
3510/// declaration.
3511void ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
3512                                              std::string& S) {
3513  // FIXME: This is not very efficient.
3514  // Encode type qualifer, 'in', 'inout', etc. for the return type.
3515  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
3516  // Encode result type.
3517  getObjCEncodingForType(Decl->getResultType(), S);
3518  // Compute size of all parameters.
3519  // Start with computing size of a pointer in number of bytes.
3520  // FIXME: There might(should) be a better way of doing this computation!
3521  SourceLocation Loc;
3522  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3523  // The first two arguments (self and _cmd) are pointers; account for
3524  // their size.
3525  CharUnits ParmOffset = 2 * PtrSize;
3526  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3527       E = Decl->sel_param_end(); PI != E; ++PI) {
3528    QualType PType = (*PI)->getType();
3529    CharUnits sz = getObjCEncodingTypeSize(PType);
3530    assert (sz.isPositive() &&
3531        "getObjCEncodingForMethodDecl - Incomplete param type");
3532    ParmOffset += sz;
3533  }
3534  S += charUnitsToString(ParmOffset);
3535  S += "@0:";
3536  S += charUnitsToString(PtrSize);
3537
3538  // Argument types.
3539  ParmOffset = 2 * PtrSize;
3540  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3541       E = Decl->sel_param_end(); PI != E; ++PI) {
3542    ParmVarDecl *PVDecl = *PI;
3543    QualType PType = PVDecl->getOriginalType();
3544    if (const ArrayType *AT =
3545          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3546      // Use array's original type only if it has known number of
3547      // elements.
3548      if (!isa<ConstantArrayType>(AT))
3549        PType = PVDecl->getType();
3550    } else if (PType->isFunctionType())
3551      PType = PVDecl->getType();
3552    // Process argument qualifiers for user supplied arguments; such as,
3553    // 'in', 'inout', etc.
3554    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
3555    getObjCEncodingForType(PType, S);
3556    S += charUnitsToString(ParmOffset);
3557    ParmOffset += getObjCEncodingTypeSize(PType);
3558  }
3559}
3560
3561/// getObjCEncodingForPropertyDecl - Return the encoded type for this
3562/// property declaration. If non-NULL, Container must be either an
3563/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
3564/// NULL when getting encodings for protocol properties.
3565/// Property attributes are stored as a comma-delimited C string. The simple
3566/// attributes readonly and bycopy are encoded as single characters. The
3567/// parametrized attributes, getter=name, setter=name, and ivar=name, are
3568/// encoded as single characters, followed by an identifier. Property types
3569/// are also encoded as a parametrized attribute. The characters used to encode
3570/// these attributes are defined by the following enumeration:
3571/// @code
3572/// enum PropertyAttributes {
3573/// kPropertyReadOnly = 'R',   // property is read-only.
3574/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
3575/// kPropertyByref = '&',  // property is a reference to the value last assigned
3576/// kPropertyDynamic = 'D',    // property is dynamic
3577/// kPropertyGetter = 'G',     // followed by getter selector name
3578/// kPropertySetter = 'S',     // followed by setter selector name
3579/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
3580/// kPropertyType = 't'              // followed by old-style type encoding.
3581/// kPropertyWeak = 'W'              // 'weak' property
3582/// kPropertyStrong = 'P'            // property GC'able
3583/// kPropertyNonAtomic = 'N'         // property non-atomic
3584/// };
3585/// @endcode
3586void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
3587                                                const Decl *Container,
3588                                                std::string& S) {
3589  // Collect information from the property implementation decl(s).
3590  bool Dynamic = false;
3591  ObjCPropertyImplDecl *SynthesizePID = 0;
3592
3593  // FIXME: Duplicated code due to poor abstraction.
3594  if (Container) {
3595    if (const ObjCCategoryImplDecl *CID =
3596        dyn_cast<ObjCCategoryImplDecl>(Container)) {
3597      for (ObjCCategoryImplDecl::propimpl_iterator
3598             i = CID->propimpl_begin(), e = CID->propimpl_end();
3599           i != e; ++i) {
3600        ObjCPropertyImplDecl *PID = *i;
3601        if (PID->getPropertyDecl() == PD) {
3602          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3603            Dynamic = true;
3604          } else {
3605            SynthesizePID = PID;
3606          }
3607        }
3608      }
3609    } else {
3610      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
3611      for (ObjCCategoryImplDecl::propimpl_iterator
3612             i = OID->propimpl_begin(), e = OID->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    }
3624  }
3625
3626  // FIXME: This is not very efficient.
3627  S = "T";
3628
3629  // Encode result type.
3630  // GCC has some special rules regarding encoding of properties which
3631  // closely resembles encoding of ivars.
3632  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
3633                             true /* outermost type */,
3634                             true /* encoding for property */);
3635
3636  if (PD->isReadOnly()) {
3637    S += ",R";
3638  } else {
3639    switch (PD->getSetterKind()) {
3640    case ObjCPropertyDecl::Assign: break;
3641    case ObjCPropertyDecl::Copy:   S += ",C"; break;
3642    case ObjCPropertyDecl::Retain: S += ",&"; break;
3643    }
3644  }
3645
3646  // It really isn't clear at all what this means, since properties
3647  // are "dynamic by default".
3648  if (Dynamic)
3649    S += ",D";
3650
3651  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
3652    S += ",N";
3653
3654  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
3655    S += ",G";
3656    S += PD->getGetterName().getAsString();
3657  }
3658
3659  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
3660    S += ",S";
3661    S += PD->getSetterName().getAsString();
3662  }
3663
3664  if (SynthesizePID) {
3665    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
3666    S += ",V";
3667    S += OID->getNameAsString();
3668  }
3669
3670  // FIXME: OBJCGC: weak & strong
3671}
3672
3673/// getLegacyIntegralTypeEncoding -
3674/// Another legacy compatibility encoding: 32-bit longs are encoded as
3675/// 'l' or 'L' , but not always.  For typedefs, we need to use
3676/// 'i' or 'I' instead if encoding a struct field, or a pointer!
3677///
3678void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
3679  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
3680    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
3681      if (BT->getKind() == BuiltinType::ULong &&
3682          ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3683        PointeeTy = UnsignedIntTy;
3684      else
3685        if (BT->getKind() == BuiltinType::Long &&
3686            ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3687          PointeeTy = IntTy;
3688    }
3689  }
3690}
3691
3692void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
3693                                        const FieldDecl *Field) {
3694  // We follow the behavior of gcc, expanding structures which are
3695  // directly pointed to, and expanding embedded structures. Note that
3696  // these rules are sufficient to prevent recursive encoding of the
3697  // same type.
3698  getObjCEncodingForTypeImpl(T, S, true, true, Field,
3699                             true /* outermost type */);
3700}
3701
3702static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
3703    switch (T->getAs<BuiltinType>()->getKind()) {
3704    default: assert(0 && "Unhandled builtin type kind");
3705    case BuiltinType::Void:       return 'v';
3706    case BuiltinType::Bool:       return 'B';
3707    case BuiltinType::Char_U:
3708    case BuiltinType::UChar:      return 'C';
3709    case BuiltinType::UShort:     return 'S';
3710    case BuiltinType::UInt:       return 'I';
3711    case BuiltinType::ULong:
3712        return
3713          (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'L' : 'Q';
3714    case BuiltinType::UInt128:    return 'T';
3715    case BuiltinType::ULongLong:  return 'Q';
3716    case BuiltinType::Char_S:
3717    case BuiltinType::SChar:      return 'c';
3718    case BuiltinType::Short:      return 's';
3719    case BuiltinType::WChar:
3720    case BuiltinType::Int:        return 'i';
3721    case BuiltinType::Long:
3722      return
3723        (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'l' : 'q';
3724    case BuiltinType::LongLong:   return 'q';
3725    case BuiltinType::Int128:     return 't';
3726    case BuiltinType::Float:      return 'f';
3727    case BuiltinType::Double:     return 'd';
3728    case BuiltinType::LongDouble: return 'D';
3729    }
3730}
3731
3732static void EncodeBitField(const ASTContext *Context, std::string& S,
3733                           QualType T, const FieldDecl *FD) {
3734  const Expr *E = FD->getBitWidth();
3735  assert(E && "bitfield width not there - getObjCEncodingForTypeImpl");
3736  ASTContext *Ctx = const_cast<ASTContext*>(Context);
3737  S += 'b';
3738  // The NeXT runtime encodes bit fields as b followed by the number of bits.
3739  // The GNU runtime requires more information; bitfields are encoded as b,
3740  // then the offset (in bits) of the first element, then the type of the
3741  // bitfield, then the size in bits.  For example, in this structure:
3742  //
3743  // struct
3744  // {
3745  //    int integer;
3746  //    int flags:2;
3747  // };
3748  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
3749  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
3750  // information is not especially sensible, but we're stuck with it for
3751  // compatibility with GCC, although providing it breaks anything that
3752  // actually uses runtime introspection and wants to work on both runtimes...
3753  if (!Ctx->getLangOptions().NeXTRuntime) {
3754    const RecordDecl *RD = FD->getParent();
3755    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
3756    // FIXME: This same linear search is also used in ExprConstant - it might
3757    // be better if the FieldDecl stored its offset.  We'd be increasing the
3758    // size of the object slightly, but saving some time every time it is used.
3759    unsigned i = 0;
3760    for (RecordDecl::field_iterator Field = RD->field_begin(),
3761                                 FieldEnd = RD->field_end();
3762         Field != FieldEnd; (void)++Field, ++i) {
3763      if (*Field == FD)
3764        break;
3765    }
3766    S += llvm::utostr(RL.getFieldOffset(i));
3767    S += ObjCEncodingForPrimitiveKind(Context, T);
3768  }
3769  unsigned N = E->EvaluateAsInt(*Ctx).getZExtValue();
3770  S += llvm::utostr(N);
3771}
3772
3773// FIXME: Use SmallString for accumulating string.
3774void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
3775                                            bool ExpandPointedToStructures,
3776                                            bool ExpandStructures,
3777                                            const FieldDecl *FD,
3778                                            bool OutermostType,
3779                                            bool EncodingProperty) {
3780  if (T->getAs<BuiltinType>()) {
3781    if (FD && FD->isBitField())
3782      return EncodeBitField(this, S, T, FD);
3783    S += ObjCEncodingForPrimitiveKind(this, T);
3784    return;
3785  }
3786
3787  if (const ComplexType *CT = T->getAs<ComplexType>()) {
3788    S += 'j';
3789    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
3790                               false);
3791    return;
3792  }
3793
3794  // encoding for pointer or r3eference types.
3795  QualType PointeeTy;
3796  if (const PointerType *PT = T->getAs<PointerType>()) {
3797    if (PT->isObjCSelType()) {
3798      S += ':';
3799      return;
3800    }
3801    PointeeTy = PT->getPointeeType();
3802  }
3803  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3804    PointeeTy = RT->getPointeeType();
3805  if (!PointeeTy.isNull()) {
3806    bool isReadOnly = false;
3807    // For historical/compatibility reasons, the read-only qualifier of the
3808    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
3809    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
3810    // Also, do not emit the 'r' for anything but the outermost type!
3811    if (isa<TypedefType>(T.getTypePtr())) {
3812      if (OutermostType && T.isConstQualified()) {
3813        isReadOnly = true;
3814        S += 'r';
3815      }
3816    } else if (OutermostType) {
3817      QualType P = PointeeTy;
3818      while (P->getAs<PointerType>())
3819        P = P->getAs<PointerType>()->getPointeeType();
3820      if (P.isConstQualified()) {
3821        isReadOnly = true;
3822        S += 'r';
3823      }
3824    }
3825    if (isReadOnly) {
3826      // Another legacy compatibility encoding. Some ObjC qualifier and type
3827      // combinations need to be rearranged.
3828      // Rewrite "in const" from "nr" to "rn"
3829      if (llvm::StringRef(S).endswith("nr"))
3830        S.replace(S.end()-2, S.end(), "rn");
3831    }
3832
3833    if (PointeeTy->isCharType()) {
3834      // char pointer types should be encoded as '*' unless it is a
3835      // type that has been typedef'd to 'BOOL'.
3836      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
3837        S += '*';
3838        return;
3839      }
3840    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
3841      // GCC binary compat: Need to convert "struct objc_class *" to "#".
3842      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
3843        S += '#';
3844        return;
3845      }
3846      // GCC binary compat: Need to convert "struct objc_object *" to "@".
3847      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
3848        S += '@';
3849        return;
3850      }
3851      // fall through...
3852    }
3853    S += '^';
3854    getLegacyIntegralTypeEncoding(PointeeTy);
3855
3856    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
3857                               NULL);
3858    return;
3859  }
3860
3861  if (const ArrayType *AT =
3862      // Ignore type qualifiers etc.
3863        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
3864    if (isa<IncompleteArrayType>(AT)) {
3865      // Incomplete arrays are encoded as a pointer to the array element.
3866      S += '^';
3867
3868      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3869                                 false, ExpandStructures, FD);
3870    } else {
3871      S += '[';
3872
3873      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
3874        S += llvm::utostr(CAT->getSize().getZExtValue());
3875      else {
3876        //Variable length arrays are encoded as a regular array with 0 elements.
3877        assert(isa<VariableArrayType>(AT) && "Unknown array type!");
3878        S += '0';
3879      }
3880
3881      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3882                                 false, ExpandStructures, FD);
3883      S += ']';
3884    }
3885    return;
3886  }
3887
3888  if (T->getAs<FunctionType>()) {
3889    S += '?';
3890    return;
3891  }
3892
3893  if (const RecordType *RTy = T->getAs<RecordType>()) {
3894    RecordDecl *RDecl = RTy->getDecl();
3895    S += RDecl->isUnion() ? '(' : '{';
3896    // Anonymous structures print as '?'
3897    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
3898      S += II->getName();
3899      if (ClassTemplateSpecializationDecl *Spec
3900          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
3901        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
3902        std::string TemplateArgsStr
3903          = TemplateSpecializationType::PrintTemplateArgumentList(
3904                                            TemplateArgs.data(),
3905                                            TemplateArgs.size(),
3906                                            (*this).PrintingPolicy);
3907
3908        S += TemplateArgsStr;
3909      }
3910    } else {
3911      S += '?';
3912    }
3913    if (ExpandStructures) {
3914      S += '=';
3915      for (RecordDecl::field_iterator Field = RDecl->field_begin(),
3916                                   FieldEnd = RDecl->field_end();
3917           Field != FieldEnd; ++Field) {
3918        if (FD) {
3919          S += '"';
3920          S += Field->getNameAsString();
3921          S += '"';
3922        }
3923
3924        // Special case bit-fields.
3925        if (Field->isBitField()) {
3926          getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
3927                                     (*Field));
3928        } else {
3929          QualType qt = Field->getType();
3930          getLegacyIntegralTypeEncoding(qt);
3931          getObjCEncodingForTypeImpl(qt, S, false, true,
3932                                     FD);
3933        }
3934      }
3935    }
3936    S += RDecl->isUnion() ? ')' : '}';
3937    return;
3938  }
3939
3940  if (T->isEnumeralType()) {
3941    if (FD && FD->isBitField())
3942      EncodeBitField(this, S, T, FD);
3943    else
3944      S += 'i';
3945    return;
3946  }
3947
3948  if (T->isBlockPointerType()) {
3949    S += "@?"; // Unlike a pointer-to-function, which is "^?".
3950    return;
3951  }
3952
3953  // Ignore protocol qualifiers when mangling at this level.
3954  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
3955    T = OT->getBaseType();
3956
3957  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
3958    // @encode(class_name)
3959    ObjCInterfaceDecl *OI = OIT->getDecl();
3960    S += '{';
3961    const IdentifierInfo *II = OI->getIdentifier();
3962    S += II->getName();
3963    S += '=';
3964    llvm::SmallVector<ObjCIvarDecl*, 32> Ivars;
3965    DeepCollectObjCIvars(OI, true, Ivars);
3966    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
3967      FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
3968      if (Field->isBitField())
3969        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
3970      else
3971        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
3972    }
3973    S += '}';
3974    return;
3975  }
3976
3977  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
3978    if (OPT->isObjCIdType()) {
3979      S += '@';
3980      return;
3981    }
3982
3983    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
3984      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
3985      // Since this is a binary compatibility issue, need to consult with runtime
3986      // folks. Fortunately, this is a *very* obsure construct.
3987      S += '#';
3988      return;
3989    }
3990
3991    if (OPT->isObjCQualifiedIdType()) {
3992      getObjCEncodingForTypeImpl(getObjCIdType(), S,
3993                                 ExpandPointedToStructures,
3994                                 ExpandStructures, FD);
3995      if (FD || EncodingProperty) {
3996        // Note that we do extended encoding of protocol qualifer list
3997        // Only when doing ivar or property encoding.
3998        S += '"';
3999        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4000             E = OPT->qual_end(); I != E; ++I) {
4001          S += '<';
4002          S += (*I)->getNameAsString();
4003          S += '>';
4004        }
4005        S += '"';
4006      }
4007      return;
4008    }
4009
4010    QualType PointeeTy = OPT->getPointeeType();
4011    if (!EncodingProperty &&
4012        isa<TypedefType>(PointeeTy.getTypePtr())) {
4013      // Another historical/compatibility reason.
4014      // We encode the underlying type which comes out as
4015      // {...};
4016      S += '^';
4017      getObjCEncodingForTypeImpl(PointeeTy, S,
4018                                 false, ExpandPointedToStructures,
4019                                 NULL);
4020      return;
4021    }
4022
4023    S += '@';
4024    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
4025      S += '"';
4026      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4027      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4028           E = OPT->qual_end(); I != E; ++I) {
4029        S += '<';
4030        S += (*I)->getNameAsString();
4031        S += '>';
4032      }
4033      S += '"';
4034    }
4035    return;
4036  }
4037
4038  // gcc just blithely ignores member pointers.
4039  // TODO: maybe there should be a mangling for these
4040  if (T->getAs<MemberPointerType>())
4041    return;
4042
4043  if (T->isVectorType()) {
4044    // This matches gcc's encoding, even though technically it is
4045    // insufficient.
4046    // FIXME. We should do a better job than gcc.
4047    return;
4048  }
4049
4050  assert(0 && "@encode for type not implemented!");
4051}
4052
4053void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4054                                                 std::string& S) const {
4055  if (QT & Decl::OBJC_TQ_In)
4056    S += 'n';
4057  if (QT & Decl::OBJC_TQ_Inout)
4058    S += 'N';
4059  if (QT & Decl::OBJC_TQ_Out)
4060    S += 'o';
4061  if (QT & Decl::OBJC_TQ_Bycopy)
4062    S += 'O';
4063  if (QT & Decl::OBJC_TQ_Byref)
4064    S += 'R';
4065  if (QT & Decl::OBJC_TQ_Oneway)
4066    S += 'V';
4067}
4068
4069void ASTContext::setBuiltinVaListType(QualType T) {
4070  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4071
4072  BuiltinVaListType = T;
4073}
4074
4075void ASTContext::setObjCIdType(QualType T) {
4076  ObjCIdTypedefType = T;
4077}
4078
4079void ASTContext::setObjCSelType(QualType T) {
4080  ObjCSelTypedefType = T;
4081}
4082
4083void ASTContext::setObjCProtoType(QualType QT) {
4084  ObjCProtoType = QT;
4085}
4086
4087void ASTContext::setObjCClassType(QualType T) {
4088  ObjCClassTypedefType = T;
4089}
4090
4091void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4092  assert(ObjCConstantStringType.isNull() &&
4093         "'NSConstantString' type already set!");
4094
4095  ObjCConstantStringType = getObjCInterfaceType(Decl);
4096}
4097
4098/// \brief Retrieve the template name that corresponds to a non-empty
4099/// lookup.
4100TemplateName ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4101                                                   UnresolvedSetIterator End) {
4102  unsigned size = End - Begin;
4103  assert(size > 1 && "set is not overloaded!");
4104
4105  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4106                          size * sizeof(FunctionTemplateDecl*));
4107  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4108
4109  NamedDecl **Storage = OT->getStorage();
4110  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4111    NamedDecl *D = *I;
4112    assert(isa<FunctionTemplateDecl>(D) ||
4113           (isa<UsingShadowDecl>(D) &&
4114            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4115    *Storage++ = D;
4116  }
4117
4118  return TemplateName(OT);
4119}
4120
4121/// \brief Retrieve the template name that represents a qualified
4122/// template name such as \c std::vector.
4123TemplateName ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4124                                                  bool TemplateKeyword,
4125                                                  TemplateDecl *Template) {
4126  // FIXME: Canonicalization?
4127  llvm::FoldingSetNodeID ID;
4128  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4129
4130  void *InsertPos = 0;
4131  QualifiedTemplateName *QTN =
4132    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4133  if (!QTN) {
4134    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4135    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4136  }
4137
4138  return TemplateName(QTN);
4139}
4140
4141/// \brief Retrieve the template name that represents a dependent
4142/// template name such as \c MetaFun::template apply.
4143TemplateName ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4144                                                  const IdentifierInfo *Name) {
4145  assert((!NNS || NNS->isDependent()) &&
4146         "Nested name specifier must be dependent");
4147
4148  llvm::FoldingSetNodeID ID;
4149  DependentTemplateName::Profile(ID, NNS, Name);
4150
4151  void *InsertPos = 0;
4152  DependentTemplateName *QTN =
4153    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4154
4155  if (QTN)
4156    return TemplateName(QTN);
4157
4158  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4159  if (CanonNNS == NNS) {
4160    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4161  } else {
4162    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4163    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4164    DependentTemplateName *CheckQTN =
4165      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4166    assert(!CheckQTN && "Dependent type name canonicalization broken");
4167    (void)CheckQTN;
4168  }
4169
4170  DependentTemplateNames.InsertNode(QTN, InsertPos);
4171  return TemplateName(QTN);
4172}
4173
4174/// \brief Retrieve the template name that represents a dependent
4175/// template name such as \c MetaFun::template operator+.
4176TemplateName
4177ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4178                                     OverloadedOperatorKind Operator) {
4179  assert((!NNS || NNS->isDependent()) &&
4180         "Nested name specifier must be dependent");
4181
4182  llvm::FoldingSetNodeID ID;
4183  DependentTemplateName::Profile(ID, NNS, Operator);
4184
4185  void *InsertPos = 0;
4186  DependentTemplateName *QTN
4187    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4188
4189  if (QTN)
4190    return TemplateName(QTN);
4191
4192  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4193  if (CanonNNS == NNS) {
4194    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4195  } else {
4196    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4197    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4198
4199    DependentTemplateName *CheckQTN
4200      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4201    assert(!CheckQTN && "Dependent template name canonicalization broken");
4202    (void)CheckQTN;
4203  }
4204
4205  DependentTemplateNames.InsertNode(QTN, InsertPos);
4206  return TemplateName(QTN);
4207}
4208
4209/// getFromTargetType - Given one of the integer types provided by
4210/// TargetInfo, produce the corresponding type. The unsigned @p Type
4211/// is actually a value of type @c TargetInfo::IntType.
4212CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4213  switch (Type) {
4214  case TargetInfo::NoInt: return CanQualType();
4215  case TargetInfo::SignedShort: return ShortTy;
4216  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4217  case TargetInfo::SignedInt: return IntTy;
4218  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4219  case TargetInfo::SignedLong: return LongTy;
4220  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4221  case TargetInfo::SignedLongLong: return LongLongTy;
4222  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4223  }
4224
4225  assert(false && "Unhandled TargetInfo::IntType value");
4226  return CanQualType();
4227}
4228
4229//===----------------------------------------------------------------------===//
4230//                        Type Predicates.
4231//===----------------------------------------------------------------------===//
4232
4233/// isObjCNSObjectType - Return true if this is an NSObject object using
4234/// NSObject attribute on a c-style pointer type.
4235/// FIXME - Make it work directly on types.
4236/// FIXME: Move to Type.
4237///
4238bool ASTContext::isObjCNSObjectType(QualType Ty) const {
4239  if (TypedefType *TDT = dyn_cast<TypedefType>(Ty)) {
4240    if (TypedefDecl *TD = TDT->getDecl())
4241      if (TD->getAttr<ObjCNSObjectAttr>())
4242        return true;
4243  }
4244  return false;
4245}
4246
4247/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4248/// garbage collection attribute.
4249///
4250Qualifiers::GC ASTContext::getObjCGCAttrKind(const QualType &Ty) const {
4251  Qualifiers::GC GCAttrs = Qualifiers::GCNone;
4252  if (getLangOptions().ObjC1 &&
4253      getLangOptions().getGCMode() != LangOptions::NonGC) {
4254    GCAttrs = Ty.getObjCGCAttr();
4255    // Default behavious under objective-c's gc is for objective-c pointers
4256    // (or pointers to them) be treated as though they were declared
4257    // as __strong.
4258    if (GCAttrs == Qualifiers::GCNone) {
4259      if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4260        GCAttrs = Qualifiers::Strong;
4261      else if (Ty->isPointerType())
4262        return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4263    }
4264    // Non-pointers have none gc'able attribute regardless of the attribute
4265    // set on them.
4266    else if (!Ty->isAnyPointerType() && !Ty->isBlockPointerType())
4267      return Qualifiers::GCNone;
4268  }
4269  return GCAttrs;
4270}
4271
4272//===----------------------------------------------------------------------===//
4273//                        Type Compatibility Testing
4274//===----------------------------------------------------------------------===//
4275
4276/// areCompatVectorTypes - Return true if the two specified vector types are
4277/// compatible.
4278static bool areCompatVectorTypes(const VectorType *LHS,
4279                                 const VectorType *RHS) {
4280  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
4281  return LHS->getElementType() == RHS->getElementType() &&
4282         LHS->getNumElements() == RHS->getNumElements();
4283}
4284
4285bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
4286                                          QualType SecondVec) {
4287  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
4288  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
4289
4290  if (hasSameUnqualifiedType(FirstVec, SecondVec))
4291    return true;
4292
4293  // Treat Neon vector types and most AltiVec vector types as if they are the
4294  // equivalent GCC vector types.
4295  const VectorType *First = FirstVec->getAs<VectorType>();
4296  const VectorType *Second = SecondVec->getAs<VectorType>();
4297  if (First->getNumElements() == Second->getNumElements() &&
4298      hasSameType(First->getElementType(), Second->getElementType()) &&
4299      First->getVectorKind() != VectorType::AltiVecPixel &&
4300      First->getVectorKind() != VectorType::AltiVecBool &&
4301      Second->getVectorKind() != VectorType::AltiVecPixel &&
4302      Second->getVectorKind() != VectorType::AltiVecBool)
4303    return true;
4304
4305  return false;
4306}
4307
4308//===----------------------------------------------------------------------===//
4309// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
4310//===----------------------------------------------------------------------===//
4311
4312/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
4313/// inheritance hierarchy of 'rProto'.
4314bool ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
4315                                                ObjCProtocolDecl *rProto) {
4316  if (lProto == rProto)
4317    return true;
4318  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
4319       E = rProto->protocol_end(); PI != E; ++PI)
4320    if (ProtocolCompatibleWithProtocol(lProto, *PI))
4321      return true;
4322  return false;
4323}
4324
4325/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
4326/// return true if lhs's protocols conform to rhs's protocol; false
4327/// otherwise.
4328bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
4329  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
4330    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
4331  return false;
4332}
4333
4334/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
4335/// Class<p1, ...>.
4336bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
4337                                                      QualType rhs) {
4338  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
4339  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4340  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
4341
4342  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4343       E = lhsQID->qual_end(); I != E; ++I) {
4344    bool match = false;
4345    ObjCProtocolDecl *lhsProto = *I;
4346    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4347         E = rhsOPT->qual_end(); J != E; ++J) {
4348      ObjCProtocolDecl *rhsProto = *J;
4349      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
4350        match = true;
4351        break;
4352      }
4353    }
4354    if (!match)
4355      return false;
4356  }
4357  return true;
4358}
4359
4360/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
4361/// ObjCQualifiedIDType.
4362bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
4363                                                   bool compare) {
4364  // Allow id<P..> and an 'id' or void* type in all cases.
4365  if (lhs->isVoidPointerType() ||
4366      lhs->isObjCIdType() || lhs->isObjCClassType())
4367    return true;
4368  else if (rhs->isVoidPointerType() ||
4369           rhs->isObjCIdType() || rhs->isObjCClassType())
4370    return true;
4371
4372  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
4373    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4374
4375    if (!rhsOPT) return false;
4376
4377    if (rhsOPT->qual_empty()) {
4378      // If the RHS is a unqualified interface pointer "NSString*",
4379      // make sure we check the class hierarchy.
4380      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4381        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4382             E = lhsQID->qual_end(); I != E; ++I) {
4383          // when comparing an id<P> on lhs with a static type on rhs,
4384          // see if static class implements all of id's protocols, directly or
4385          // through its super class and categories.
4386          if (!rhsID->ClassImplementsProtocol(*I, true))
4387            return false;
4388        }
4389      }
4390      // If there are no qualifiers and no interface, we have an 'id'.
4391      return true;
4392    }
4393    // Both the right and left sides have qualifiers.
4394    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4395         E = lhsQID->qual_end(); I != E; ++I) {
4396      ObjCProtocolDecl *lhsProto = *I;
4397      bool match = false;
4398
4399      // when comparing an id<P> on lhs with a static type on rhs,
4400      // see if static class implements all of id's protocols, directly or
4401      // through its super class and categories.
4402      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4403           E = rhsOPT->qual_end(); J != E; ++J) {
4404        ObjCProtocolDecl *rhsProto = *J;
4405        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4406            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4407          match = true;
4408          break;
4409        }
4410      }
4411      // If the RHS is a qualified interface pointer "NSString<P>*",
4412      // make sure we check the class hierarchy.
4413      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4414        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4415             E = lhsQID->qual_end(); I != E; ++I) {
4416          // when comparing an id<P> on lhs with a static type on rhs,
4417          // see if static class implements all of id's protocols, directly or
4418          // through its super class and categories.
4419          if (rhsID->ClassImplementsProtocol(*I, true)) {
4420            match = true;
4421            break;
4422          }
4423        }
4424      }
4425      if (!match)
4426        return false;
4427    }
4428
4429    return true;
4430  }
4431
4432  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
4433  assert(rhsQID && "One of the LHS/RHS should be id<x>");
4434
4435  if (const ObjCObjectPointerType *lhsOPT =
4436        lhs->getAsObjCInterfacePointerType()) {
4437    // If both the right and left sides have qualifiers.
4438    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
4439         E = lhsOPT->qual_end(); I != E; ++I) {
4440      ObjCProtocolDecl *lhsProto = *I;
4441      bool match = false;
4442
4443      // when comparing an id<P> on rhs with a static type on lhs,
4444      // see if static class implements all of id's protocols, directly or
4445      // through its super class and categories.
4446      // First, lhs protocols in the qualifier list must be found, direct
4447      // or indirect in rhs's qualifier list or it is a mismatch.
4448      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4449           E = rhsQID->qual_end(); J != E; ++J) {
4450        ObjCProtocolDecl *rhsProto = *J;
4451        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4452            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4453          match = true;
4454          break;
4455        }
4456      }
4457      if (!match)
4458        return false;
4459    }
4460
4461    // Static class's protocols, or its super class or category protocols
4462    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
4463    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
4464      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4465      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
4466      // This is rather dubious but matches gcc's behavior. If lhs has
4467      // no type qualifier and its class has no static protocol(s)
4468      // assume that it is mismatch.
4469      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
4470        return false;
4471      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4472           LHSInheritedProtocols.begin(),
4473           E = LHSInheritedProtocols.end(); I != E; ++I) {
4474        bool match = false;
4475        ObjCProtocolDecl *lhsProto = (*I);
4476        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4477             E = rhsQID->qual_end(); J != E; ++J) {
4478          ObjCProtocolDecl *rhsProto = *J;
4479          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4480              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4481            match = true;
4482            break;
4483          }
4484        }
4485        if (!match)
4486          return false;
4487      }
4488    }
4489    return true;
4490  }
4491  return false;
4492}
4493
4494/// canAssignObjCInterfaces - Return true if the two interface types are
4495/// compatible for assignment from RHS to LHS.  This handles validation of any
4496/// protocol qualifiers on the LHS or RHS.
4497///
4498bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
4499                                         const ObjCObjectPointerType *RHSOPT) {
4500  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4501  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4502
4503  // If either type represents the built-in 'id' or 'Class' types, return true.
4504  if (LHS->isObjCUnqualifiedIdOrClass() ||
4505      RHS->isObjCUnqualifiedIdOrClass())
4506    return true;
4507
4508  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
4509    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4510                                             QualType(RHSOPT,0),
4511                                             false);
4512
4513  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
4514    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
4515                                                QualType(RHSOPT,0));
4516
4517  // If we have 2 user-defined types, fall into that path.
4518  if (LHS->getInterface() && RHS->getInterface())
4519    return canAssignObjCInterfaces(LHS, RHS);
4520
4521  return false;
4522}
4523
4524/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
4525/// for providing type-safty for objective-c pointers used to pass/return
4526/// arguments in block literals. When passed as arguments, passing 'A*' where
4527/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
4528/// not OK. For the return type, the opposite is not OK.
4529bool ASTContext::canAssignObjCInterfacesInBlockPointer(
4530                                         const ObjCObjectPointerType *LHSOPT,
4531                                         const ObjCObjectPointerType *RHSOPT) {
4532  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
4533    return true;
4534
4535  if (LHSOPT->isObjCBuiltinType()) {
4536    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
4537  }
4538
4539  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
4540    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4541                                             QualType(RHSOPT,0),
4542                                             false);
4543
4544  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
4545  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
4546  if (LHS && RHS)  { // We have 2 user-defined types.
4547    if (LHS != RHS) {
4548      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
4549        return false;
4550      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
4551        return true;
4552    }
4553    else
4554      return true;
4555  }
4556  return false;
4557}
4558
4559/// getIntersectionOfProtocols - This routine finds the intersection of set
4560/// of protocols inherited from two distinct objective-c pointer objects.
4561/// It is used to build composite qualifier list of the composite type of
4562/// the conditional expression involving two objective-c pointer objects.
4563static
4564void getIntersectionOfProtocols(ASTContext &Context,
4565                                const ObjCObjectPointerType *LHSOPT,
4566                                const ObjCObjectPointerType *RHSOPT,
4567      llvm::SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
4568
4569  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4570  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4571  assert(LHS->getInterface() && "LHS must have an interface base");
4572  assert(RHS->getInterface() && "RHS must have an interface base");
4573
4574  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
4575  unsigned LHSNumProtocols = LHS->getNumProtocols();
4576  if (LHSNumProtocols > 0)
4577    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
4578  else {
4579    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4580    Context.CollectInheritedProtocols(LHS->getInterface(),
4581                                      LHSInheritedProtocols);
4582    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
4583                                LHSInheritedProtocols.end());
4584  }
4585
4586  unsigned RHSNumProtocols = RHS->getNumProtocols();
4587  if (RHSNumProtocols > 0) {
4588    ObjCProtocolDecl **RHSProtocols =
4589      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
4590    for (unsigned i = 0; i < RHSNumProtocols; ++i)
4591      if (InheritedProtocolSet.count(RHSProtocols[i]))
4592        IntersectionOfProtocols.push_back(RHSProtocols[i]);
4593  }
4594  else {
4595    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
4596    Context.CollectInheritedProtocols(RHS->getInterface(),
4597                                      RHSInheritedProtocols);
4598    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4599         RHSInheritedProtocols.begin(),
4600         E = RHSInheritedProtocols.end(); I != E; ++I)
4601      if (InheritedProtocolSet.count((*I)))
4602        IntersectionOfProtocols.push_back((*I));
4603  }
4604}
4605
4606/// areCommonBaseCompatible - Returns common base class of the two classes if
4607/// one found. Note that this is O'2 algorithm. But it will be called as the
4608/// last type comparison in a ?-exp of ObjC pointer types before a
4609/// warning is issued. So, its invokation is extremely rare.
4610QualType ASTContext::areCommonBaseCompatible(
4611                                          const ObjCObjectPointerType *Lptr,
4612                                          const ObjCObjectPointerType *Rptr) {
4613  const ObjCObjectType *LHS = Lptr->getObjectType();
4614  const ObjCObjectType *RHS = Rptr->getObjectType();
4615  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
4616  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
4617  if (!LDecl || !RDecl)
4618    return QualType();
4619
4620  while ((LDecl = LDecl->getSuperClass())) {
4621    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
4622    if (canAssignObjCInterfaces(LHS, RHS)) {
4623      llvm::SmallVector<ObjCProtocolDecl *, 8> Protocols;
4624      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
4625
4626      QualType Result = QualType(LHS, 0);
4627      if (!Protocols.empty())
4628        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
4629      Result = getObjCObjectPointerType(Result);
4630      return Result;
4631    }
4632  }
4633
4634  return QualType();
4635}
4636
4637bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
4638                                         const ObjCObjectType *RHS) {
4639  assert(LHS->getInterface() && "LHS is not an interface type");
4640  assert(RHS->getInterface() && "RHS is not an interface type");
4641
4642  // Verify that the base decls are compatible: the RHS must be a subclass of
4643  // the LHS.
4644  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
4645    return false;
4646
4647  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
4648  // protocol qualified at all, then we are good.
4649  if (LHS->getNumProtocols() == 0)
4650    return true;
4651
4652  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't, then it
4653  // isn't a superset.
4654  if (RHS->getNumProtocols() == 0)
4655    return true;  // FIXME: should return false!
4656
4657  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
4658                                     LHSPE = LHS->qual_end();
4659       LHSPI != LHSPE; LHSPI++) {
4660    bool RHSImplementsProtocol = false;
4661
4662    // If the RHS doesn't implement the protocol on the left, the types
4663    // are incompatible.
4664    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
4665                                       RHSPE = RHS->qual_end();
4666         RHSPI != RHSPE; RHSPI++) {
4667      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
4668        RHSImplementsProtocol = true;
4669        break;
4670      }
4671    }
4672    // FIXME: For better diagnostics, consider passing back the protocol name.
4673    if (!RHSImplementsProtocol)
4674      return false;
4675  }
4676  // The RHS implements all protocols listed on the LHS.
4677  return true;
4678}
4679
4680bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
4681  // get the "pointed to" types
4682  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
4683  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
4684
4685  if (!LHSOPT || !RHSOPT)
4686    return false;
4687
4688  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
4689         canAssignObjCInterfaces(RHSOPT, LHSOPT);
4690}
4691
4692bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
4693  return canAssignObjCInterfaces(
4694                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
4695                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
4696}
4697
4698/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
4699/// both shall have the identically qualified version of a compatible type.
4700/// C99 6.2.7p1: Two types have compatible types if their types are the
4701/// same. See 6.7.[2,3,5] for additional rules.
4702bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
4703                                    bool CompareUnqualified) {
4704  if (getLangOptions().CPlusPlus)
4705    return hasSameType(LHS, RHS);
4706
4707  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
4708}
4709
4710bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
4711  return !mergeTypes(LHS, RHS, true).isNull();
4712}
4713
4714/// mergeTransparentUnionType - if T is a transparent union type and a member
4715/// of T is compatible with SubType, return the merged type, else return
4716/// QualType()
4717QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
4718                                               bool OfBlockPointer,
4719                                               bool Unqualified) {
4720  if (const RecordType *UT = T->getAsUnionType()) {
4721    RecordDecl *UD = UT->getDecl();
4722    if (UD->hasAttr<TransparentUnionAttr>()) {
4723      for (RecordDecl::field_iterator it = UD->field_begin(),
4724           itend = UD->field_end(); it != itend; ++it) {
4725        QualType ET = it->getType();
4726        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
4727        if (!MT.isNull())
4728          return MT;
4729      }
4730    }
4731  }
4732
4733  return QualType();
4734}
4735
4736/// mergeFunctionArgumentTypes - merge two types which appear as function
4737/// argument types
4738QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
4739                                                bool OfBlockPointer,
4740                                                bool Unqualified) {
4741  // GNU extension: two types are compatible if they appear as a function
4742  // argument, one of the types is a transparent union type and the other
4743  // type is compatible with a union member
4744  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
4745                                              Unqualified);
4746  if (!lmerge.isNull())
4747    return lmerge;
4748
4749  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
4750                                              Unqualified);
4751  if (!rmerge.isNull())
4752    return rmerge;
4753
4754  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
4755}
4756
4757QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
4758                                        bool OfBlockPointer,
4759                                        bool Unqualified) {
4760  const FunctionType *lbase = lhs->getAs<FunctionType>();
4761  const FunctionType *rbase = rhs->getAs<FunctionType>();
4762  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
4763  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
4764  bool allLTypes = true;
4765  bool allRTypes = true;
4766
4767  // Check return type
4768  QualType retType;
4769  if (OfBlockPointer)
4770    retType = mergeTypes(rbase->getResultType(), lbase->getResultType(), true,
4771                         Unqualified);
4772  else
4773   retType = mergeTypes(lbase->getResultType(), rbase->getResultType(),
4774                        false, Unqualified);
4775  if (retType.isNull()) return QualType();
4776
4777  if (Unqualified)
4778    retType = retType.getUnqualifiedType();
4779
4780  CanQualType LRetType = getCanonicalType(lbase->getResultType());
4781  CanQualType RRetType = getCanonicalType(rbase->getResultType());
4782  if (Unqualified) {
4783    LRetType = LRetType.getUnqualifiedType();
4784    RRetType = RRetType.getUnqualifiedType();
4785  }
4786
4787  if (getCanonicalType(retType) != LRetType)
4788    allLTypes = false;
4789  if (getCanonicalType(retType) != RRetType)
4790    allRTypes = false;
4791  // FIXME: double check this
4792  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
4793  //                           rbase->getRegParmAttr() != 0 &&
4794  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
4795  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
4796  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
4797  unsigned RegParm = lbaseInfo.getRegParm() == 0 ? rbaseInfo.getRegParm() :
4798      lbaseInfo.getRegParm();
4799  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
4800  if (NoReturn != lbaseInfo.getNoReturn() ||
4801      RegParm != lbaseInfo.getRegParm())
4802    allLTypes = false;
4803  if (NoReturn != rbaseInfo.getNoReturn() ||
4804      RegParm != rbaseInfo.getRegParm())
4805    allRTypes = false;
4806  CallingConv lcc = lbaseInfo.getCC();
4807  CallingConv rcc = rbaseInfo.getCC();
4808  // Compatible functions must have compatible calling conventions
4809  if (!isSameCallConv(lcc, rcc))
4810    return QualType();
4811
4812  if (lproto && rproto) { // two C99 style function prototypes
4813    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
4814           "C++ shouldn't be here");
4815    unsigned lproto_nargs = lproto->getNumArgs();
4816    unsigned rproto_nargs = rproto->getNumArgs();
4817
4818    // Compatible functions must have the same number of arguments
4819    if (lproto_nargs != rproto_nargs)
4820      return QualType();
4821
4822    // Variadic and non-variadic functions aren't compatible
4823    if (lproto->isVariadic() != rproto->isVariadic())
4824      return QualType();
4825
4826    if (lproto->getTypeQuals() != rproto->getTypeQuals())
4827      return QualType();
4828
4829    // Check argument compatibility
4830    llvm::SmallVector<QualType, 10> types;
4831    for (unsigned i = 0; i < lproto_nargs; i++) {
4832      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
4833      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
4834      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
4835                                                    OfBlockPointer,
4836                                                    Unqualified);
4837      if (argtype.isNull()) return QualType();
4838
4839      if (Unqualified)
4840        argtype = argtype.getUnqualifiedType();
4841
4842      types.push_back(argtype);
4843      if (Unqualified) {
4844        largtype = largtype.getUnqualifiedType();
4845        rargtype = rargtype.getUnqualifiedType();
4846      }
4847
4848      if (getCanonicalType(argtype) != getCanonicalType(largtype))
4849        allLTypes = false;
4850      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
4851        allRTypes = false;
4852    }
4853    if (allLTypes) return lhs;
4854    if (allRTypes) return rhs;
4855    return getFunctionType(retType, types.begin(), types.size(),
4856                           lproto->isVariadic(), lproto->getTypeQuals(),
4857                           false, false, 0, 0,
4858                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4859  }
4860
4861  if (lproto) allRTypes = false;
4862  if (rproto) allLTypes = false;
4863
4864  const FunctionProtoType *proto = lproto ? lproto : rproto;
4865  if (proto) {
4866    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
4867    if (proto->isVariadic()) return QualType();
4868    // Check that the types are compatible with the types that
4869    // would result from default argument promotions (C99 6.7.5.3p15).
4870    // The only types actually affected are promotable integer
4871    // types and floats, which would be passed as a different
4872    // type depending on whether the prototype is visible.
4873    unsigned proto_nargs = proto->getNumArgs();
4874    for (unsigned i = 0; i < proto_nargs; ++i) {
4875      QualType argTy = proto->getArgType(i);
4876
4877      // Look at the promotion type of enum types, since that is the type used
4878      // to pass enum values.
4879      if (const EnumType *Enum = argTy->getAs<EnumType>())
4880        argTy = Enum->getDecl()->getPromotionType();
4881
4882      if (argTy->isPromotableIntegerType() ||
4883          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
4884        return QualType();
4885    }
4886
4887    if (allLTypes) return lhs;
4888    if (allRTypes) return rhs;
4889    return getFunctionType(retType, proto->arg_type_begin(),
4890                           proto->getNumArgs(), proto->isVariadic(),
4891                           proto->getTypeQuals(),
4892                           false, false, 0, 0,
4893                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4894  }
4895
4896  if (allLTypes) return lhs;
4897  if (allRTypes) return rhs;
4898  FunctionType::ExtInfo Info(NoReturn, RegParm, lcc);
4899  return getFunctionNoProtoType(retType, Info);
4900}
4901
4902QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
4903                                bool OfBlockPointer,
4904                                bool Unqualified) {
4905  // C++ [expr]: If an expression initially has the type "reference to T", the
4906  // type is adjusted to "T" prior to any further analysis, the expression
4907  // designates the object or function denoted by the reference, and the
4908  // expression is an lvalue unless the reference is an rvalue reference and
4909  // the expression is a function call (possibly inside parentheses).
4910  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
4911  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
4912
4913  if (Unqualified) {
4914    LHS = LHS.getUnqualifiedType();
4915    RHS = RHS.getUnqualifiedType();
4916  }
4917
4918  QualType LHSCan = getCanonicalType(LHS),
4919           RHSCan = getCanonicalType(RHS);
4920
4921  // If two types are identical, they are compatible.
4922  if (LHSCan == RHSCan)
4923    return LHS;
4924
4925  // If the qualifiers are different, the types aren't compatible... mostly.
4926  Qualifiers LQuals = LHSCan.getLocalQualifiers();
4927  Qualifiers RQuals = RHSCan.getLocalQualifiers();
4928  if (LQuals != RQuals) {
4929    // If any of these qualifiers are different, we have a type
4930    // mismatch.
4931    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
4932        LQuals.getAddressSpace() != RQuals.getAddressSpace())
4933      return QualType();
4934
4935    // Exactly one GC qualifier difference is allowed: __strong is
4936    // okay if the other type has no GC qualifier but is an Objective
4937    // C object pointer (i.e. implicitly strong by default).  We fix
4938    // this by pretending that the unqualified type was actually
4939    // qualified __strong.
4940    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
4941    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
4942    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
4943
4944    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
4945      return QualType();
4946
4947    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
4948      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
4949    }
4950    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
4951      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
4952    }
4953    return QualType();
4954  }
4955
4956  // Okay, qualifiers are equal.
4957
4958  Type::TypeClass LHSClass = LHSCan->getTypeClass();
4959  Type::TypeClass RHSClass = RHSCan->getTypeClass();
4960
4961  // We want to consider the two function types to be the same for these
4962  // comparisons, just force one to the other.
4963  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
4964  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
4965
4966  // Same as above for arrays
4967  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
4968    LHSClass = Type::ConstantArray;
4969  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
4970    RHSClass = Type::ConstantArray;
4971
4972  // ObjCInterfaces are just specialized ObjCObjects.
4973  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
4974  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
4975
4976  // Canonicalize ExtVector -> Vector.
4977  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
4978  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
4979
4980  // If the canonical type classes don't match.
4981  if (LHSClass != RHSClass) {
4982    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
4983    // a signed integer type, or an unsigned integer type.
4984    // Compatibility is based on the underlying type, not the promotion
4985    // type.
4986    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
4987      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
4988        return RHS;
4989    }
4990    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
4991      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
4992        return LHS;
4993    }
4994
4995    return QualType();
4996  }
4997
4998  // The canonical type classes match.
4999  switch (LHSClass) {
5000#define TYPE(Class, Base)
5001#define ABSTRACT_TYPE(Class, Base)
5002#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
5003#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
5004#define DEPENDENT_TYPE(Class, Base) case Type::Class:
5005#include "clang/AST/TypeNodes.def"
5006    assert(false && "Non-canonical and dependent types shouldn't get here");
5007    return QualType();
5008
5009  case Type::LValueReference:
5010  case Type::RValueReference:
5011  case Type::MemberPointer:
5012    assert(false && "C++ should never be in mergeTypes");
5013    return QualType();
5014
5015  case Type::ObjCInterface:
5016  case Type::IncompleteArray:
5017  case Type::VariableArray:
5018  case Type::FunctionProto:
5019  case Type::ExtVector:
5020    assert(false && "Types are eliminated above");
5021    return QualType();
5022
5023  case Type::Pointer:
5024  {
5025    // Merge two pointer types, while trying to preserve typedef info
5026    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
5027    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
5028    if (Unqualified) {
5029      LHSPointee = LHSPointee.getUnqualifiedType();
5030      RHSPointee = RHSPointee.getUnqualifiedType();
5031    }
5032    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
5033                                     Unqualified);
5034    if (ResultType.isNull()) return QualType();
5035    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5036      return LHS;
5037    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5038      return RHS;
5039    return getPointerType(ResultType);
5040  }
5041  case Type::BlockPointer:
5042  {
5043    // Merge two block pointer types, while trying to preserve typedef info
5044    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
5045    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
5046    if (Unqualified) {
5047      LHSPointee = LHSPointee.getUnqualifiedType();
5048      RHSPointee = RHSPointee.getUnqualifiedType();
5049    }
5050    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
5051                                     Unqualified);
5052    if (ResultType.isNull()) return QualType();
5053    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5054      return LHS;
5055    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5056      return RHS;
5057    return getBlockPointerType(ResultType);
5058  }
5059  case Type::ConstantArray:
5060  {
5061    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
5062    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
5063    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
5064      return QualType();
5065
5066    QualType LHSElem = getAsArrayType(LHS)->getElementType();
5067    QualType RHSElem = getAsArrayType(RHS)->getElementType();
5068    if (Unqualified) {
5069      LHSElem = LHSElem.getUnqualifiedType();
5070      RHSElem = RHSElem.getUnqualifiedType();
5071    }
5072
5073    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
5074    if (ResultType.isNull()) return QualType();
5075    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5076      return LHS;
5077    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5078      return RHS;
5079    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
5080                                          ArrayType::ArraySizeModifier(), 0);
5081    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
5082                                          ArrayType::ArraySizeModifier(), 0);
5083    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
5084    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
5085    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5086      return LHS;
5087    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5088      return RHS;
5089    if (LVAT) {
5090      // FIXME: This isn't correct! But tricky to implement because
5091      // the array's size has to be the size of LHS, but the type
5092      // has to be different.
5093      return LHS;
5094    }
5095    if (RVAT) {
5096      // FIXME: This isn't correct! But tricky to implement because
5097      // the array's size has to be the size of RHS, but the type
5098      // has to be different.
5099      return RHS;
5100    }
5101    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
5102    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
5103    return getIncompleteArrayType(ResultType,
5104                                  ArrayType::ArraySizeModifier(), 0);
5105  }
5106  case Type::FunctionNoProto:
5107    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
5108  case Type::Record:
5109  case Type::Enum:
5110    return QualType();
5111  case Type::Builtin:
5112    // Only exactly equal builtin types are compatible, which is tested above.
5113    return QualType();
5114  case Type::Complex:
5115    // Distinct complex types are incompatible.
5116    return QualType();
5117  case Type::Vector:
5118    // FIXME: The merged type should be an ExtVector!
5119    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
5120                             RHSCan->getAs<VectorType>()))
5121      return LHS;
5122    return QualType();
5123  case Type::ObjCObject: {
5124    // Check if the types are assignment compatible.
5125    // FIXME: This should be type compatibility, e.g. whether
5126    // "LHS x; RHS x;" at global scope is legal.
5127    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
5128    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
5129    if (canAssignObjCInterfaces(LHSIface, RHSIface))
5130      return LHS;
5131
5132    return QualType();
5133  }
5134  case Type::ObjCObjectPointer: {
5135    if (OfBlockPointer) {
5136      if (canAssignObjCInterfacesInBlockPointer(
5137                                          LHS->getAs<ObjCObjectPointerType>(),
5138                                          RHS->getAs<ObjCObjectPointerType>()))
5139      return LHS;
5140      return QualType();
5141    }
5142    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
5143                                RHS->getAs<ObjCObjectPointerType>()))
5144      return LHS;
5145
5146    return QualType();
5147    }
5148  }
5149
5150  return QualType();
5151}
5152
5153/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
5154/// 'RHS' attributes and returns the merged version; including for function
5155/// return types.
5156QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
5157  QualType LHSCan = getCanonicalType(LHS),
5158  RHSCan = getCanonicalType(RHS);
5159  // If two types are identical, they are compatible.
5160  if (LHSCan == RHSCan)
5161    return LHS;
5162  if (RHSCan->isFunctionType()) {
5163    if (!LHSCan->isFunctionType())
5164      return QualType();
5165    QualType OldReturnType =
5166      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
5167    QualType NewReturnType =
5168      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
5169    QualType ResReturnType =
5170      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
5171    if (ResReturnType.isNull())
5172      return QualType();
5173    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
5174      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
5175      // In either case, use OldReturnType to build the new function type.
5176      const FunctionType *F = LHS->getAs<FunctionType>();
5177      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
5178        FunctionType::ExtInfo Info = getFunctionExtInfo(LHS);
5179        QualType ResultType
5180          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
5181                                  FPT->getNumArgs(), FPT->isVariadic(),
5182                                  FPT->getTypeQuals(),
5183                                  FPT->hasExceptionSpec(),
5184                                  FPT->hasAnyExceptionSpec(),
5185                                  FPT->getNumExceptions(),
5186                                  FPT->exception_begin(),
5187                                  Info);
5188        return ResultType;
5189      }
5190    }
5191    return QualType();
5192  }
5193
5194  // If the qualifiers are different, the types can still be merged.
5195  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5196  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5197  if (LQuals != RQuals) {
5198    // If any of these qualifiers are different, we have a type mismatch.
5199    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5200        LQuals.getAddressSpace() != RQuals.getAddressSpace())
5201      return QualType();
5202
5203    // Exactly one GC qualifier difference is allowed: __strong is
5204    // okay if the other type has no GC qualifier but is an Objective
5205    // C object pointer (i.e. implicitly strong by default).  We fix
5206    // this by pretending that the unqualified type was actually
5207    // qualified __strong.
5208    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5209    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5210    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5211
5212    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5213      return QualType();
5214
5215    if (GC_L == Qualifiers::Strong)
5216      return LHS;
5217    if (GC_R == Qualifiers::Strong)
5218      return RHS;
5219    return QualType();
5220  }
5221
5222  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
5223    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5224    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5225    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
5226    if (ResQT == LHSBaseQT)
5227      return LHS;
5228    if (ResQT == RHSBaseQT)
5229      return RHS;
5230  }
5231  return QualType();
5232}
5233
5234//===----------------------------------------------------------------------===//
5235//                         Integer Predicates
5236//===----------------------------------------------------------------------===//
5237
5238unsigned ASTContext::getIntWidth(QualType T) {
5239  if (EnumType *ET = dyn_cast<EnumType>(T))
5240    T = ET->getDecl()->getIntegerType();
5241  if (T->isBooleanType())
5242    return 1;
5243  // For builtin types, just use the standard type sizing method
5244  return (unsigned)getTypeSize(T);
5245}
5246
5247QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
5248  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
5249
5250  // Turn <4 x signed int> -> <4 x unsigned int>
5251  if (const VectorType *VTy = T->getAs<VectorType>())
5252    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
5253                         VTy->getNumElements(), VTy->getVectorKind());
5254
5255  // For enums, we return the unsigned version of the base type.
5256  if (const EnumType *ETy = T->getAs<EnumType>())
5257    T = ETy->getDecl()->getIntegerType();
5258
5259  const BuiltinType *BTy = T->getAs<BuiltinType>();
5260  assert(BTy && "Unexpected signed integer type");
5261  switch (BTy->getKind()) {
5262  case BuiltinType::Char_S:
5263  case BuiltinType::SChar:
5264    return UnsignedCharTy;
5265  case BuiltinType::Short:
5266    return UnsignedShortTy;
5267  case BuiltinType::Int:
5268    return UnsignedIntTy;
5269  case BuiltinType::Long:
5270    return UnsignedLongTy;
5271  case BuiltinType::LongLong:
5272    return UnsignedLongLongTy;
5273  case BuiltinType::Int128:
5274    return UnsignedInt128Ty;
5275  default:
5276    assert(0 && "Unexpected signed integer type");
5277    return QualType();
5278  }
5279}
5280
5281ExternalASTSource::~ExternalASTSource() { }
5282
5283void ExternalASTSource::PrintStats() { }
5284
5285ASTMutationListener::~ASTMutationListener() { }
5286
5287
5288//===----------------------------------------------------------------------===//
5289//                          Builtin Type Computation
5290//===----------------------------------------------------------------------===//
5291
5292/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
5293/// pointer over the consumed characters.  This returns the resultant type.  If
5294/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
5295/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
5296/// a vector of "i*".
5297///
5298/// RequiresICE is filled in on return to indicate whether the value is required
5299/// to be an Integer Constant Expression.
5300static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
5301                                  ASTContext::GetBuiltinTypeError &Error,
5302                                  bool &RequiresICE,
5303                                  bool AllowTypeModifiers) {
5304  // Modifiers.
5305  int HowLong = 0;
5306  bool Signed = false, Unsigned = false;
5307  RequiresICE = false;
5308
5309  // Read the prefixed modifiers first.
5310  bool Done = false;
5311  while (!Done) {
5312    switch (*Str++) {
5313    default: Done = true; --Str; break;
5314    case 'I':
5315      RequiresICE = true;
5316      break;
5317    case 'S':
5318      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
5319      assert(!Signed && "Can't use 'S' modifier multiple times!");
5320      Signed = true;
5321      break;
5322    case 'U':
5323      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
5324      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
5325      Unsigned = true;
5326      break;
5327    case 'L':
5328      assert(HowLong <= 2 && "Can't have LLLL modifier");
5329      ++HowLong;
5330      break;
5331    }
5332  }
5333
5334  QualType Type;
5335
5336  // Read the base type.
5337  switch (*Str++) {
5338  default: assert(0 && "Unknown builtin type letter!");
5339  case 'v':
5340    assert(HowLong == 0 && !Signed && !Unsigned &&
5341           "Bad modifiers used with 'v'!");
5342    Type = Context.VoidTy;
5343    break;
5344  case 'f':
5345    assert(HowLong == 0 && !Signed && !Unsigned &&
5346           "Bad modifiers used with 'f'!");
5347    Type = Context.FloatTy;
5348    break;
5349  case 'd':
5350    assert(HowLong < 2 && !Signed && !Unsigned &&
5351           "Bad modifiers used with 'd'!");
5352    if (HowLong)
5353      Type = Context.LongDoubleTy;
5354    else
5355      Type = Context.DoubleTy;
5356    break;
5357  case 's':
5358    assert(HowLong == 0 && "Bad modifiers used with 's'!");
5359    if (Unsigned)
5360      Type = Context.UnsignedShortTy;
5361    else
5362      Type = Context.ShortTy;
5363    break;
5364  case 'i':
5365    if (HowLong == 3)
5366      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
5367    else if (HowLong == 2)
5368      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
5369    else if (HowLong == 1)
5370      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
5371    else
5372      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
5373    break;
5374  case 'c':
5375    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
5376    if (Signed)
5377      Type = Context.SignedCharTy;
5378    else if (Unsigned)
5379      Type = Context.UnsignedCharTy;
5380    else
5381      Type = Context.CharTy;
5382    break;
5383  case 'b': // boolean
5384    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
5385    Type = Context.BoolTy;
5386    break;
5387  case 'z':  // size_t.
5388    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
5389    Type = Context.getSizeType();
5390    break;
5391  case 'F':
5392    Type = Context.getCFConstantStringType();
5393    break;
5394  case 'G':
5395    Type = Context.getObjCIdType();
5396    break;
5397  case 'H':
5398    Type = Context.getObjCSelType();
5399    break;
5400  case 'a':
5401    Type = Context.getBuiltinVaListType();
5402    assert(!Type.isNull() && "builtin va list type not initialized!");
5403    break;
5404  case 'A':
5405    // This is a "reference" to a va_list; however, what exactly
5406    // this means depends on how va_list is defined. There are two
5407    // different kinds of va_list: ones passed by value, and ones
5408    // passed by reference.  An example of a by-value va_list is
5409    // x86, where va_list is a char*. An example of by-ref va_list
5410    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
5411    // we want this argument to be a char*&; for x86-64, we want
5412    // it to be a __va_list_tag*.
5413    Type = Context.getBuiltinVaListType();
5414    assert(!Type.isNull() && "builtin va list type not initialized!");
5415    if (Type->isArrayType())
5416      Type = Context.getArrayDecayedType(Type);
5417    else
5418      Type = Context.getLValueReferenceType(Type);
5419    break;
5420  case 'V': {
5421    char *End;
5422    unsigned NumElements = strtoul(Str, &End, 10);
5423    assert(End != Str && "Missing vector size");
5424    Str = End;
5425
5426    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
5427                                             RequiresICE, false);
5428    assert(!RequiresICE && "Can't require vector ICE");
5429
5430    // TODO: No way to make AltiVec vectors in builtins yet.
5431    Type = Context.getVectorType(ElementType, NumElements,
5432                                 VectorType::GenericVector);
5433    break;
5434  }
5435  case 'X': {
5436    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
5437                                             false);
5438    assert(!RequiresICE && "Can't require complex ICE");
5439    Type = Context.getComplexType(ElementType);
5440    break;
5441  }
5442  case 'P':
5443    Type = Context.getFILEType();
5444    if (Type.isNull()) {
5445      Error = ASTContext::GE_Missing_stdio;
5446      return QualType();
5447    }
5448    break;
5449  case 'J':
5450    if (Signed)
5451      Type = Context.getsigjmp_bufType();
5452    else
5453      Type = Context.getjmp_bufType();
5454
5455    if (Type.isNull()) {
5456      Error = ASTContext::GE_Missing_setjmp;
5457      return QualType();
5458    }
5459    break;
5460  }
5461
5462  // If there are modifiers and if we're allowed to parse them, go for it.
5463  Done = !AllowTypeModifiers;
5464  while (!Done) {
5465    switch (char c = *Str++) {
5466    default: Done = true; --Str; break;
5467    case '*':
5468    case '&': {
5469      // Both pointers and references can have their pointee types
5470      // qualified with an address space.
5471      char *End;
5472      unsigned AddrSpace = strtoul(Str, &End, 10);
5473      if (End != Str && AddrSpace != 0) {
5474        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
5475        Str = End;
5476      }
5477      if (c == '*')
5478        Type = Context.getPointerType(Type);
5479      else
5480        Type = Context.getLValueReferenceType(Type);
5481      break;
5482    }
5483    // FIXME: There's no way to have a built-in with an rvalue ref arg.
5484    case 'C':
5485      Type = Type.withConst();
5486      break;
5487    case 'D':
5488      Type = Context.getVolatileType(Type);
5489      break;
5490    }
5491  }
5492
5493  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
5494         "Integer constant 'I' type must be an integer");
5495
5496  return Type;
5497}
5498
5499/// GetBuiltinType - Return the type for the specified builtin.
5500QualType ASTContext::GetBuiltinType(unsigned Id,
5501                                    GetBuiltinTypeError &Error,
5502                                    unsigned *IntegerConstantArgs) {
5503  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
5504
5505  llvm::SmallVector<QualType, 8> ArgTypes;
5506
5507  bool RequiresICE = false;
5508  Error = GE_None;
5509  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
5510                                       RequiresICE, true);
5511  if (Error != GE_None)
5512    return QualType();
5513
5514  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
5515
5516  while (TypeStr[0] && TypeStr[0] != '.') {
5517    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
5518    if (Error != GE_None)
5519      return QualType();
5520
5521    // If this argument is required to be an IntegerConstantExpression and the
5522    // caller cares, fill in the bitmask we return.
5523    if (RequiresICE && IntegerConstantArgs)
5524      *IntegerConstantArgs |= 1 << ArgTypes.size();
5525
5526    // Do array -> pointer decay.  The builtin should use the decayed type.
5527    if (Ty->isArrayType())
5528      Ty = getArrayDecayedType(Ty);
5529
5530    ArgTypes.push_back(Ty);
5531  }
5532
5533  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
5534         "'.' should only occur at end of builtin type list!");
5535
5536  // handle untyped/variadic arguments "T c99Style();" or "T cppStyle(...);".
5537  if (ArgTypes.size() == 0 && TypeStr[0] == '.')
5538    return getFunctionNoProtoType(ResType);
5539
5540  // FIXME: Should we create noreturn types?
5541  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(),
5542                         TypeStr[0] == '.', 0, false, false, 0, 0,
5543                         FunctionType::ExtInfo());
5544}
5545
5546GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
5547  GVALinkage External = GVA_StrongExternal;
5548
5549  Linkage L = FD->getLinkage();
5550  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5551      FD->getType()->getLinkage() == UniqueExternalLinkage)
5552    L = UniqueExternalLinkage;
5553
5554  switch (L) {
5555  case NoLinkage:
5556  case InternalLinkage:
5557  case UniqueExternalLinkage:
5558    return GVA_Internal;
5559
5560  case ExternalLinkage:
5561    switch (FD->getTemplateSpecializationKind()) {
5562    case TSK_Undeclared:
5563    case TSK_ExplicitSpecialization:
5564      External = GVA_StrongExternal;
5565      break;
5566
5567    case TSK_ExplicitInstantiationDefinition:
5568      return GVA_ExplicitTemplateInstantiation;
5569
5570    case TSK_ExplicitInstantiationDeclaration:
5571    case TSK_ImplicitInstantiation:
5572      External = GVA_TemplateInstantiation;
5573      break;
5574    }
5575  }
5576
5577  if (!FD->isInlined())
5578    return External;
5579
5580  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
5581    // GNU or C99 inline semantics. Determine whether this symbol should be
5582    // externally visible.
5583    if (FD->isInlineDefinitionExternallyVisible())
5584      return External;
5585
5586    // C99 inline semantics, where the symbol is not externally visible.
5587    return GVA_C99Inline;
5588  }
5589
5590  // C++0x [temp.explicit]p9:
5591  //   [ Note: The intent is that an inline function that is the subject of
5592  //   an explicit instantiation declaration will still be implicitly
5593  //   instantiated when used so that the body can be considered for
5594  //   inlining, but that no out-of-line copy of the inline function would be
5595  //   generated in the translation unit. -- end note ]
5596  if (FD->getTemplateSpecializationKind()
5597                                       == TSK_ExplicitInstantiationDeclaration)
5598    return GVA_C99Inline;
5599
5600  return GVA_CXXInline;
5601}
5602
5603GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
5604  // If this is a static data member, compute the kind of template
5605  // specialization. Otherwise, this variable is not part of a
5606  // template.
5607  TemplateSpecializationKind TSK = TSK_Undeclared;
5608  if (VD->isStaticDataMember())
5609    TSK = VD->getTemplateSpecializationKind();
5610
5611  Linkage L = VD->getLinkage();
5612  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5613      VD->getType()->getLinkage() == UniqueExternalLinkage)
5614    L = UniqueExternalLinkage;
5615
5616  switch (L) {
5617  case NoLinkage:
5618  case InternalLinkage:
5619  case UniqueExternalLinkage:
5620    return GVA_Internal;
5621
5622  case ExternalLinkage:
5623    switch (TSK) {
5624    case TSK_Undeclared:
5625    case TSK_ExplicitSpecialization:
5626      return GVA_StrongExternal;
5627
5628    case TSK_ExplicitInstantiationDeclaration:
5629      llvm_unreachable("Variable should not be instantiated");
5630      // Fall through to treat this like any other instantiation.
5631
5632    case TSK_ExplicitInstantiationDefinition:
5633      return GVA_ExplicitTemplateInstantiation;
5634
5635    case TSK_ImplicitInstantiation:
5636      return GVA_TemplateInstantiation;
5637    }
5638  }
5639
5640  return GVA_StrongExternal;
5641}
5642
5643bool ASTContext::DeclMustBeEmitted(const Decl *D) {
5644  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
5645    if (!VD->isFileVarDecl())
5646      return false;
5647  } else if (!isa<FunctionDecl>(D))
5648    return false;
5649
5650  // Weak references don't produce any output by themselves.
5651  if (D->hasAttr<WeakRefAttr>())
5652    return false;
5653
5654  // Aliases and used decls are required.
5655  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
5656    return true;
5657
5658  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
5659    // Forward declarations aren't required.
5660    if (!FD->isThisDeclarationADefinition())
5661      return false;
5662
5663    // Constructors and destructors are required.
5664    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
5665      return true;
5666
5667    // The key function for a class is required.
5668    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
5669      const CXXRecordDecl *RD = MD->getParent();
5670      if (MD->isOutOfLine() && RD->isDynamicClass()) {
5671        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
5672        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
5673          return true;
5674      }
5675    }
5676
5677    GVALinkage Linkage = GetGVALinkageForFunction(FD);
5678
5679    // static, static inline, always_inline, and extern inline functions can
5680    // always be deferred.  Normal inline functions can be deferred in C99/C++.
5681    // Implicit template instantiations can also be deferred in C++.
5682    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
5683        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
5684      return false;
5685    return true;
5686  }
5687
5688  const VarDecl *VD = cast<VarDecl>(D);
5689  assert(VD->isFileVarDecl() && "Expected file scoped var");
5690
5691  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
5692    return false;
5693
5694  // Structs that have non-trivial constructors or destructors are required.
5695
5696  // FIXME: Handle references.
5697  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
5698    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
5699      if (RD->hasDefinition() &&
5700          (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()))
5701        return true;
5702    }
5703  }
5704
5705  GVALinkage L = GetGVALinkageForVariable(VD);
5706  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
5707    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
5708      return false;
5709  }
5710
5711  return true;
5712}
5713
5714CallingConv ASTContext::getDefaultMethodCallConv() {
5715  // Pass through to the C++ ABI object
5716  return ABI->getDefaultMethodCallConv();
5717}
5718
5719bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) {
5720  // Pass through to the C++ ABI object
5721  return ABI->isNearlyEmpty(RD);
5722}
5723
5724CXXABI::~CXXABI() {}
5725