ASTContext.cpp revision a7e6845660f91ec611427e1db842780e1ec12bdb 
1//===--- ASTContext.cpp - Context to hold long-lived AST nodes ------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements the ASTContext interface.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/AST/ASTContext.h"
15#include "clang/AST/CharUnits.h"
16#include "clang/AST/DeclCXX.h"
17#include "clang/AST/DeclObjC.h"
18#include "clang/AST/DeclTemplate.h"
19#include "clang/AST/TypeLoc.h"
20#include "clang/AST/Expr.h"
21#include "clang/AST/ExprCXX.h"
22#include "clang/AST/ExternalASTSource.h"
23#include "clang/AST/RecordLayout.h"
24#include "clang/Basic/Builtins.h"
25#include "clang/Basic/SourceManager.h"
26#include "clang/Basic/TargetInfo.h"
27#include "llvm/ADT/SmallString.h"
28#include "llvm/ADT/StringExtras.h"
29#include "llvm/Support/MathExtras.h"
30#include "llvm/Support/raw_ostream.h"
31#include "CXXABI.h"
32
33using namespace clang;
34
35unsigned ASTContext::NumImplicitDefaultConstructors;
36unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
37unsigned ASTContext::NumImplicitCopyConstructors;
38unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
39unsigned ASTContext::NumImplicitCopyAssignmentOperators;
40unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
41unsigned ASTContext::NumImplicitDestructors;
42unsigned ASTContext::NumImplicitDestructorsDeclared;
43
44enum FloatingRank {
45  FloatRank, DoubleRank, LongDoubleRank
46};
47
48void
49ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
50                                               TemplateTemplateParmDecl *Parm) {
51  ID.AddInteger(Parm->getDepth());
52  ID.AddInteger(Parm->getPosition());
53  // FIXME: Parameter pack
54
55  TemplateParameterList *Params = Parm->getTemplateParameters();
56  ID.AddInteger(Params->size());
57  for (TemplateParameterList::const_iterator P = Params->begin(),
58                                          PEnd = Params->end();
59       P != PEnd; ++P) {
60    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
61      ID.AddInteger(0);
62      ID.AddBoolean(TTP->isParameterPack());
63      continue;
64    }
65
66    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
67      ID.AddInteger(1);
68      // FIXME: Parameter pack
69      ID.AddPointer(NTTP->getType().getAsOpaquePtr());
70      continue;
71    }
72
73    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
74    ID.AddInteger(2);
75    Profile(ID, TTP);
76  }
77}
78
79TemplateTemplateParmDecl *
80ASTContext::getCanonicalTemplateTemplateParmDecl(
81                                                 TemplateTemplateParmDecl *TTP) {
82  // Check if we already have a canonical template template parameter.
83  llvm::FoldingSetNodeID ID;
84  CanonicalTemplateTemplateParm::Profile(ID, TTP);
85  void *InsertPos = 0;
86  CanonicalTemplateTemplateParm *Canonical
87    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
88  if (Canonical)
89    return Canonical->getParam();
90
91  // Build a canonical template parameter list.
92  TemplateParameterList *Params = TTP->getTemplateParameters();
93  llvm::SmallVector<NamedDecl *, 4> CanonParams;
94  CanonParams.reserve(Params->size());
95  for (TemplateParameterList::const_iterator P = Params->begin(),
96                                          PEnd = Params->end();
97       P != PEnd; ++P) {
98    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
99      CanonParams.push_back(
100                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
101                                               SourceLocation(), TTP->getDepth(),
102                                               TTP->getIndex(), 0, false,
103                                               TTP->isParameterPack()));
104    else if (NonTypeTemplateParmDecl *NTTP
105             = dyn_cast<NonTypeTemplateParmDecl>(*P))
106      CanonParams.push_back(
107            NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
108                                            SourceLocation(), NTTP->getDepth(),
109                                            NTTP->getPosition(), 0,
110                                            getCanonicalType(NTTP->getType()),
111                                            0));
112    else
113      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
114                                           cast<TemplateTemplateParmDecl>(*P)));
115  }
116
117  TemplateTemplateParmDecl *CanonTTP
118    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
119                                       SourceLocation(), TTP->getDepth(),
120                                       TTP->getPosition(), 0,
121                         TemplateParameterList::Create(*this, SourceLocation(),
122                                                       SourceLocation(),
123                                                       CanonParams.data(),
124                                                       CanonParams.size(),
125                                                       SourceLocation()));
126
127  // Get the new insert position for the node we care about.
128  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
129  assert(Canonical == 0 && "Shouldn't be in the map!");
130  (void)Canonical;
131
132  // Create the canonical template template parameter entry.
133  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
134  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
135  return CanonTTP;
136}
137
138CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
139  if (!LangOpts.CPlusPlus) return 0;
140
141  switch (T.getCXXABI()) {
142  case CXXABI_ARM:
143    return CreateARMCXXABI(*this);
144  case CXXABI_Itanium:
145    return CreateItaniumCXXABI(*this);
146  case CXXABI_Microsoft:
147    return CreateMicrosoftCXXABI(*this);
148  }
149  return 0;
150}
151
152ASTContext::ASTContext(const LangOptions& LOpts, SourceManager &SM,
153                       const TargetInfo &t,
154                       IdentifierTable &idents, SelectorTable &sels,
155                       Builtin::Context &builtins,
156                       unsigned size_reserve) :
157  TemplateSpecializationTypes(this_()),
158  DependentTemplateSpecializationTypes(this_()),
159  GlobalNestedNameSpecifier(0), IsInt128Installed(false),
160  CFConstantStringTypeDecl(0), NSConstantStringTypeDecl(0),
161  ObjCFastEnumerationStateTypeDecl(0), FILEDecl(0), jmp_bufDecl(0),
162  sigjmp_bufDecl(0), BlockDescriptorType(0), BlockDescriptorExtendedType(0),
163  NullTypeSourceInfo(QualType()),
164  SourceMgr(SM), LangOpts(LOpts), ABI(createCXXABI(t)), Target(t),
165  Idents(idents), Selectors(sels),
166  BuiltinInfo(builtins),
167  DeclarationNames(*this),
168  ExternalSource(0), PrintingPolicy(LOpts),
169  LastSDM(0, 0),
170  UniqueBlockByRefTypeID(0), UniqueBlockParmTypeID(0) {
171  ObjCIdRedefinitionType = QualType();
172  ObjCClassRedefinitionType = QualType();
173  ObjCSelRedefinitionType = QualType();
174  if (size_reserve > 0) Types.reserve(size_reserve);
175  TUDecl = TranslationUnitDecl::Create(*this);
176  InitBuiltinTypes();
177}
178
179ASTContext::~ASTContext() {
180  // Release the DenseMaps associated with DeclContext objects.
181  // FIXME: Is this the ideal solution?
182  ReleaseDeclContextMaps();
183
184  // Call all of the deallocation functions.
185  for (unsigned I = 0, N = Deallocations.size(); I != N; ++I)
186    Deallocations[I].first(Deallocations[I].second);
187
188  // Release all of the memory associated with overridden C++ methods.
189  for (llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::iterator
190         OM = OverriddenMethods.begin(), OMEnd = OverriddenMethods.end();
191       OM != OMEnd; ++OM)
192    OM->second.Destroy();
193
194  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
195  // because they can contain DenseMaps.
196  for (llvm::DenseMap<const ObjCContainerDecl*,
197       const ASTRecordLayout*>::iterator
198       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
199    // Increment in loop to prevent using deallocated memory.
200    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
201      R->Destroy(*this);
202
203  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
204       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
205    // Increment in loop to prevent using deallocated memory.
206    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
207      R->Destroy(*this);
208  }
209  }
210
211void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
212  Deallocations.push_back(std::make_pair(Callback, Data));
213}
214
215void
216ASTContext::setExternalSource(llvm::OwningPtr<ExternalASTSource> &Source) {
217  ExternalSource.reset(Source.take());
218}
219
220void ASTContext::PrintStats() const {
221  fprintf(stderr, "*** AST Context Stats:\n");
222  fprintf(stderr, "  %d types total.\n", (int)Types.size());
223
224  unsigned counts[] = {
225#define TYPE(Name, Parent) 0,
226#define ABSTRACT_TYPE(Name, Parent)
227#include "clang/AST/TypeNodes.def"
228    0 // Extra
229  };
230
231  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
232    Type *T = Types[i];
233    counts[(unsigned)T->getTypeClass()]++;
234  }
235
236  unsigned Idx = 0;
237  unsigned TotalBytes = 0;
238#define TYPE(Name, Parent)                                              \
239  if (counts[Idx])                                                      \
240    fprintf(stderr, "    %d %s types\n", (int)counts[Idx], #Name);      \
241  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
242  ++Idx;
243#define ABSTRACT_TYPE(Name, Parent)
244#include "clang/AST/TypeNodes.def"
245
246  fprintf(stderr, "Total bytes = %d\n", int(TotalBytes));
247
248  // Implicit special member functions.
249  fprintf(stderr, "  %u/%u implicit default constructors created\n",
250          NumImplicitDefaultConstructorsDeclared,
251          NumImplicitDefaultConstructors);
252  fprintf(stderr, "  %u/%u implicit copy constructors created\n",
253          NumImplicitCopyConstructorsDeclared,
254          NumImplicitCopyConstructors);
255  fprintf(stderr, "  %u/%u implicit copy assignment operators created\n",
256          NumImplicitCopyAssignmentOperatorsDeclared,
257          NumImplicitCopyAssignmentOperators);
258  fprintf(stderr, "  %u/%u implicit destructors created\n",
259          NumImplicitDestructorsDeclared, NumImplicitDestructors);
260
261  if (ExternalSource.get()) {
262    fprintf(stderr, "\n");
263    ExternalSource->PrintStats();
264  }
265
266  BumpAlloc.PrintStats();
267}
268
269
270void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
271  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
272  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
273  Types.push_back(Ty);
274}
275
276void ASTContext::InitBuiltinTypes() {
277  assert(VoidTy.isNull() && "Context reinitialized?");
278
279  // C99 6.2.5p19.
280  InitBuiltinType(VoidTy,              BuiltinType::Void);
281
282  // C99 6.2.5p2.
283  InitBuiltinType(BoolTy,              BuiltinType::Bool);
284  // C99 6.2.5p3.
285  if (LangOpts.CharIsSigned)
286    InitBuiltinType(CharTy,            BuiltinType::Char_S);
287  else
288    InitBuiltinType(CharTy,            BuiltinType::Char_U);
289  // C99 6.2.5p4.
290  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
291  InitBuiltinType(ShortTy,             BuiltinType::Short);
292  InitBuiltinType(IntTy,               BuiltinType::Int);
293  InitBuiltinType(LongTy,              BuiltinType::Long);
294  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
295
296  // C99 6.2.5p6.
297  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
298  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
299  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
300  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
301  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
302
303  // C99 6.2.5p10.
304  InitBuiltinType(FloatTy,             BuiltinType::Float);
305  InitBuiltinType(DoubleTy,            BuiltinType::Double);
306  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
307
308  // GNU extension, 128-bit integers.
309  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
310  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
311
312  if (LangOpts.CPlusPlus) // C++ 3.9.1p5
313    InitBuiltinType(WCharTy,           BuiltinType::WChar);
314  else // C99
315    WCharTy = getFromTargetType(Target.getWCharType());
316
317  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
318    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
319  else // C99
320    Char16Ty = getFromTargetType(Target.getChar16Type());
321
322  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
323    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
324  else // C99
325    Char32Ty = getFromTargetType(Target.getChar32Type());
326
327  // Placeholder type for functions.
328  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
329
330  // Placeholder type for type-dependent expressions whose type is
331  // completely unknown. No code should ever check a type against
332  // DependentTy and users should never see it; however, it is here to
333  // help diagnose failures to properly check for type-dependent
334  // expressions.
335  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
336
337  // Placeholder type for C++0x auto declarations whose real type has
338  // not yet been deduced.
339  InitBuiltinType(UndeducedAutoTy, BuiltinType::UndeducedAuto);
340
341  // C99 6.2.5p11.
342  FloatComplexTy      = getComplexType(FloatTy);
343  DoubleComplexTy     = getComplexType(DoubleTy);
344  LongDoubleComplexTy = getComplexType(LongDoubleTy);
345
346  BuiltinVaListType = QualType();
347
348  // "Builtin" typedefs set by Sema::ActOnTranslationUnitScope().
349  ObjCIdTypedefType = QualType();
350  ObjCClassTypedefType = QualType();
351  ObjCSelTypedefType = QualType();
352
353  // Builtin types for 'id', 'Class', and 'SEL'.
354  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
355  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
356  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
357
358  ObjCConstantStringType = QualType();
359
360  // void * type
361  VoidPtrTy = getPointerType(VoidTy);
362
363  // nullptr type (C++0x 2.14.7)
364  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
365}
366
367MemberSpecializationInfo *
368ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
369  assert(Var->isStaticDataMember() && "Not a static data member");
370  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
371    = InstantiatedFromStaticDataMember.find(Var);
372  if (Pos == InstantiatedFromStaticDataMember.end())
373    return 0;
374
375  return Pos->second;
376}
377
378void
379ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
380                                                TemplateSpecializationKind TSK,
381                                          SourceLocation PointOfInstantiation) {
382  assert(Inst->isStaticDataMember() && "Not a static data member");
383  assert(Tmpl->isStaticDataMember() && "Not a static data member");
384  assert(!InstantiatedFromStaticDataMember[Inst] &&
385         "Already noted what static data member was instantiated from");
386  InstantiatedFromStaticDataMember[Inst]
387    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
388}
389
390NamedDecl *
391ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
392  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
393    = InstantiatedFromUsingDecl.find(UUD);
394  if (Pos == InstantiatedFromUsingDecl.end())
395    return 0;
396
397  return Pos->second;
398}
399
400void
401ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
402  assert((isa<UsingDecl>(Pattern) ||
403          isa<UnresolvedUsingValueDecl>(Pattern) ||
404          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
405         "pattern decl is not a using decl");
406  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
407  InstantiatedFromUsingDecl[Inst] = Pattern;
408}
409
410UsingShadowDecl *
411ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
412  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
413    = InstantiatedFromUsingShadowDecl.find(Inst);
414  if (Pos == InstantiatedFromUsingShadowDecl.end())
415    return 0;
416
417  return Pos->second;
418}
419
420void
421ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
422                                               UsingShadowDecl *Pattern) {
423  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
424  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
425}
426
427FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
428  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
429    = InstantiatedFromUnnamedFieldDecl.find(Field);
430  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
431    return 0;
432
433  return Pos->second;
434}
435
436void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
437                                                     FieldDecl *Tmpl) {
438  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
439  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
440  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
441         "Already noted what unnamed field was instantiated from");
442
443  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
444}
445
446ASTContext::overridden_cxx_method_iterator
447ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
448  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
449    = OverriddenMethods.find(Method);
450  if (Pos == OverriddenMethods.end())
451    return 0;
452
453  return Pos->second.begin();
454}
455
456ASTContext::overridden_cxx_method_iterator
457ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
458  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
459    = OverriddenMethods.find(Method);
460  if (Pos == OverriddenMethods.end())
461    return 0;
462
463  return Pos->second.end();
464}
465
466unsigned
467ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
468  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
469    = OverriddenMethods.find(Method);
470  if (Pos == OverriddenMethods.end())
471    return 0;
472
473  return Pos->second.size();
474}
475
476void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
477                                     const CXXMethodDecl *Overridden) {
478  OverriddenMethods[Method].push_back(Overridden);
479}
480
481//===----------------------------------------------------------------------===//
482//                         Type Sizing and Analysis
483//===----------------------------------------------------------------------===//
484
485/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
486/// scalar floating point type.
487const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
488  const BuiltinType *BT = T->getAs<BuiltinType>();
489  assert(BT && "Not a floating point type!");
490  switch (BT->getKind()) {
491  default: assert(0 && "Not a floating point type!");
492  case BuiltinType::Float:      return Target.getFloatFormat();
493  case BuiltinType::Double:     return Target.getDoubleFormat();
494  case BuiltinType::LongDouble: return Target.getLongDoubleFormat();
495  }
496}
497
498/// getDeclAlign - Return a conservative estimate of the alignment of the
499/// specified decl.  Note that bitfields do not have a valid alignment, so
500/// this method will assert on them.
501/// If @p RefAsPointee, references are treated like their underlying type
502/// (for alignof), else they're treated like pointers (for CodeGen).
503CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) {
504  unsigned Align = Target.getCharWidth();
505
506  Align = std::max(Align, D->getMaxAlignment());
507
508  if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
509    QualType T = VD->getType();
510    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
511      if (RefAsPointee)
512        T = RT->getPointeeType();
513      else
514        T = getPointerType(RT->getPointeeType());
515    }
516    if (!T->isIncompleteType() && !T->isFunctionType()) {
517      unsigned MinWidth = Target.getLargeArrayMinWidth();
518      unsigned ArrayAlign = Target.getLargeArrayAlign();
519      if (isa<VariableArrayType>(T) && MinWidth != 0)
520        Align = std::max(Align, ArrayAlign);
521      if (ConstantArrayType *CT = dyn_cast<ConstantArrayType>(T)) {
522        unsigned Size = getTypeSize(CT);
523        if (MinWidth != 0 && MinWidth <= Size)
524          Align = std::max(Align, ArrayAlign);
525      }
526      // Incomplete or function types default to 1.
527      while (isa<VariableArrayType>(T) || isa<IncompleteArrayType>(T))
528        T = cast<ArrayType>(T)->getElementType();
529
530      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
531    }
532    if (const FieldDecl *FD = dyn_cast<FieldDecl>(VD)) {
533      // In the case of a field in a packed struct, we want the minimum
534      // of the alignment of the field and the alignment of the struct.
535      Align = std::min(Align,
536        getPreferredTypeAlign(FD->getParent()->getTypeForDecl()));
537    }
538  }
539
540  return CharUnits::fromQuantity(Align / Target.getCharWidth());
541}
542
543std::pair<CharUnits, CharUnits>
544ASTContext::getTypeInfoInChars(const Type *T) {
545  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
546  return std::make_pair(CharUnits::fromQuantity(Info.first / getCharWidth()),
547                        CharUnits::fromQuantity(Info.second / getCharWidth()));
548}
549
550std::pair<CharUnits, CharUnits>
551ASTContext::getTypeInfoInChars(QualType T) {
552  return getTypeInfoInChars(T.getTypePtr());
553}
554
555/// getTypeSize - Return the size of the specified type, in bits.  This method
556/// does not work on incomplete types.
557///
558/// FIXME: Pointers into different addr spaces could have different sizes and
559/// alignment requirements: getPointerInfo should take an AddrSpace, this
560/// should take a QualType, &c.
561std::pair<uint64_t, unsigned>
562ASTContext::getTypeInfo(const Type *T) {
563  uint64_t Width=0;
564  unsigned Align=8;
565  switch (T->getTypeClass()) {
566#define TYPE(Class, Base)
567#define ABSTRACT_TYPE(Class, Base)
568#define NON_CANONICAL_TYPE(Class, Base)
569#define DEPENDENT_TYPE(Class, Base) case Type::Class:
570#include "clang/AST/TypeNodes.def"
571    assert(false && "Should not see dependent types");
572    break;
573
574  case Type::FunctionNoProto:
575  case Type::FunctionProto:
576    // GCC extension: alignof(function) = 32 bits
577    Width = 0;
578    Align = 32;
579    break;
580
581  case Type::IncompleteArray:
582  case Type::VariableArray:
583    Width = 0;
584    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
585    break;
586
587  case Type::ConstantArray: {
588    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
589
590    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
591    Width = EltInfo.first*CAT->getSize().getZExtValue();
592    Align = EltInfo.second;
593    break;
594  }
595  case Type::ExtVector:
596  case Type::Vector: {
597    const VectorType *VT = cast<VectorType>(T);
598    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
599    Width = EltInfo.first*VT->getNumElements();
600    Align = Width;
601    // If the alignment is not a power of 2, round up to the next power of 2.
602    // This happens for non-power-of-2 length vectors.
603    if (Align & (Align-1)) {
604      Align = llvm::NextPowerOf2(Align);
605      Width = llvm::RoundUpToAlignment(Width, Align);
606    }
607    break;
608  }
609
610  case Type::Builtin:
611    switch (cast<BuiltinType>(T)->getKind()) {
612    default: assert(0 && "Unknown builtin type!");
613    case BuiltinType::Void:
614      // GCC extension: alignof(void) = 8 bits.
615      Width = 0;
616      Align = 8;
617      break;
618
619    case BuiltinType::Bool:
620      Width = Target.getBoolWidth();
621      Align = Target.getBoolAlign();
622      break;
623    case BuiltinType::Char_S:
624    case BuiltinType::Char_U:
625    case BuiltinType::UChar:
626    case BuiltinType::SChar:
627      Width = Target.getCharWidth();
628      Align = Target.getCharAlign();
629      break;
630    case BuiltinType::WChar:
631      Width = Target.getWCharWidth();
632      Align = Target.getWCharAlign();
633      break;
634    case BuiltinType::Char16:
635      Width = Target.getChar16Width();
636      Align = Target.getChar16Align();
637      break;
638    case BuiltinType::Char32:
639      Width = Target.getChar32Width();
640      Align = Target.getChar32Align();
641      break;
642    case BuiltinType::UShort:
643    case BuiltinType::Short:
644      Width = Target.getShortWidth();
645      Align = Target.getShortAlign();
646      break;
647    case BuiltinType::UInt:
648    case BuiltinType::Int:
649      Width = Target.getIntWidth();
650      Align = Target.getIntAlign();
651      break;
652    case BuiltinType::ULong:
653    case BuiltinType::Long:
654      Width = Target.getLongWidth();
655      Align = Target.getLongAlign();
656      break;
657    case BuiltinType::ULongLong:
658    case BuiltinType::LongLong:
659      Width = Target.getLongLongWidth();
660      Align = Target.getLongLongAlign();
661      break;
662    case BuiltinType::Int128:
663    case BuiltinType::UInt128:
664      Width = 128;
665      Align = 128; // int128_t is 128-bit aligned on all targets.
666      break;
667    case BuiltinType::Float:
668      Width = Target.getFloatWidth();
669      Align = Target.getFloatAlign();
670      break;
671    case BuiltinType::Double:
672      Width = Target.getDoubleWidth();
673      Align = Target.getDoubleAlign();
674      break;
675    case BuiltinType::LongDouble:
676      Width = Target.getLongDoubleWidth();
677      Align = Target.getLongDoubleAlign();
678      break;
679    case BuiltinType::NullPtr:
680      Width = Target.getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
681      Align = Target.getPointerAlign(0); //   == sizeof(void*)
682      break;
683    case BuiltinType::ObjCId:
684    case BuiltinType::ObjCClass:
685    case BuiltinType::ObjCSel:
686      Width = Target.getPointerWidth(0);
687      Align = Target.getPointerAlign(0);
688      break;
689    }
690    break;
691  case Type::ObjCObjectPointer:
692    Width = Target.getPointerWidth(0);
693    Align = Target.getPointerAlign(0);
694    break;
695  case Type::BlockPointer: {
696    unsigned AS = cast<BlockPointerType>(T)->getPointeeType().getAddressSpace();
697    Width = Target.getPointerWidth(AS);
698    Align = Target.getPointerAlign(AS);
699    break;
700  }
701  case Type::LValueReference:
702  case Type::RValueReference: {
703    // alignof and sizeof should never enter this code path here, so we go
704    // the pointer route.
705    unsigned AS = cast<ReferenceType>(T)->getPointeeType().getAddressSpace();
706    Width = Target.getPointerWidth(AS);
707    Align = Target.getPointerAlign(AS);
708    break;
709  }
710  case Type::Pointer: {
711    unsigned AS = cast<PointerType>(T)->getPointeeType().getAddressSpace();
712    Width = Target.getPointerWidth(AS);
713    Align = Target.getPointerAlign(AS);
714    break;
715  }
716  case Type::MemberPointer: {
717    const MemberPointerType *MPT = cast<MemberPointerType>(T);
718    std::pair<uint64_t, unsigned> PtrDiffInfo =
719      getTypeInfo(getPointerDiffType());
720    Width = PtrDiffInfo.first * ABI->getMemberPointerSize(MPT);
721    Align = PtrDiffInfo.second;
722    break;
723  }
724  case Type::Complex: {
725    // Complex types have the same alignment as their elements, but twice the
726    // size.
727    std::pair<uint64_t, unsigned> EltInfo =
728      getTypeInfo(cast<ComplexType>(T)->getElementType());
729    Width = EltInfo.first*2;
730    Align = EltInfo.second;
731    break;
732  }
733  case Type::ObjCObject:
734    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
735  case Type::ObjCInterface: {
736    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
737    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
738    Width = Layout.getSize();
739    Align = Layout.getAlignment();
740    break;
741  }
742  case Type::Record:
743  case Type::Enum: {
744    const TagType *TT = cast<TagType>(T);
745
746    if (TT->getDecl()->isInvalidDecl()) {
747      Width = 1;
748      Align = 1;
749      break;
750    }
751
752    if (const EnumType *ET = dyn_cast<EnumType>(TT))
753      return getTypeInfo(ET->getDecl()->getIntegerType());
754
755    const RecordType *RT = cast<RecordType>(TT);
756    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
757    Width = Layout.getSize();
758    Align = Layout.getAlignment();
759    break;
760  }
761
762  case Type::SubstTemplateTypeParm:
763    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
764                       getReplacementType().getTypePtr());
765
766  case Type::Typedef: {
767    const TypedefDecl *Typedef = cast<TypedefType>(T)->getDecl();
768    Align = std::max(Typedef->getMaxAlignment(),
769                     getTypeAlign(Typedef->getUnderlyingType().getTypePtr()));
770    Width = getTypeSize(Typedef->getUnderlyingType().getTypePtr());
771    break;
772  }
773
774  case Type::TypeOfExpr:
775    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
776                         .getTypePtr());
777
778  case Type::TypeOf:
779    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
780
781  case Type::Decltype:
782    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
783                        .getTypePtr());
784
785  case Type::Elaborated:
786    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
787
788  case Type::TemplateSpecialization:
789    assert(getCanonicalType(T) != T &&
790           "Cannot request the size of a dependent type");
791    // FIXME: this is likely to be wrong once we support template
792    // aliases, since a template alias could refer to a typedef that
793    // has an __aligned__ attribute on it.
794    return getTypeInfo(getCanonicalType(T));
795  }
796
797  assert(Align && (Align & (Align-1)) == 0 && "Alignment must be power of 2");
798  return std::make_pair(Width, Align);
799}
800
801/// getTypeSizeInChars - Return the size of the specified type, in characters.
802/// This method does not work on incomplete types.
803CharUnits ASTContext::getTypeSizeInChars(QualType T) {
804  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
805}
806CharUnits ASTContext::getTypeSizeInChars(const Type *T) {
807  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
808}
809
810/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
811/// characters. This method does not work on incomplete types.
812CharUnits ASTContext::getTypeAlignInChars(QualType T) {
813  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
814}
815CharUnits ASTContext::getTypeAlignInChars(const Type *T) {
816  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
817}
818
819/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
820/// type for the current target in bits.  This can be different than the ABI
821/// alignment in cases where it is beneficial for performance to overalign
822/// a data type.
823unsigned ASTContext::getPreferredTypeAlign(const Type *T) {
824  unsigned ABIAlign = getTypeAlign(T);
825
826  // Double and long long should be naturally aligned if possible.
827  if (const ComplexType* CT = T->getAs<ComplexType>())
828    T = CT->getElementType().getTypePtr();
829  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
830      T->isSpecificBuiltinType(BuiltinType::LongLong))
831    return std::max(ABIAlign, (unsigned)getTypeSize(T));
832
833  return ABIAlign;
834}
835
836/// ShallowCollectObjCIvars -
837/// Collect all ivars, including those synthesized, in the current class.
838///
839void ASTContext::ShallowCollectObjCIvars(const ObjCInterfaceDecl *OI,
840                                 llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
841  // FIXME. This need be removed but there are two many places which
842  // assume const-ness of ObjCInterfaceDecl
843  ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
844  for (ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
845        Iv= Iv->getNextIvar())
846    Ivars.push_back(Iv);
847}
848
849/// DeepCollectObjCIvars -
850/// This routine first collects all declared, but not synthesized, ivars in
851/// super class and then collects all ivars, including those synthesized for
852/// current class. This routine is used for implementation of current class
853/// when all ivars, declared and synthesized are known.
854///
855void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
856                                      bool leafClass,
857                                llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
858  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
859    DeepCollectObjCIvars(SuperClass, false, Ivars);
860  if (!leafClass) {
861    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
862         E = OI->ivar_end(); I != E; ++I)
863      Ivars.push_back(*I);
864  }
865  else
866    ShallowCollectObjCIvars(OI, Ivars);
867}
868
869/// CollectInheritedProtocols - Collect all protocols in current class and
870/// those inherited by it.
871void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
872                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
873  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
874    for (ObjCInterfaceDecl::protocol_iterator P = OI->protocol_begin(),
875         PE = OI->protocol_end(); P != PE; ++P) {
876      ObjCProtocolDecl *Proto = (*P);
877      Protocols.insert(Proto);
878      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
879           PE = Proto->protocol_end(); P != PE; ++P) {
880        Protocols.insert(*P);
881        CollectInheritedProtocols(*P, Protocols);
882      }
883    }
884
885    // Categories of this Interface.
886    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
887         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
888      CollectInheritedProtocols(CDeclChain, Protocols);
889    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
890      while (SD) {
891        CollectInheritedProtocols(SD, Protocols);
892        SD = SD->getSuperClass();
893      }
894  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
895    for (ObjCInterfaceDecl::protocol_iterator P = OC->protocol_begin(),
896         PE = OC->protocol_end(); P != PE; ++P) {
897      ObjCProtocolDecl *Proto = (*P);
898      Protocols.insert(Proto);
899      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
900           PE = Proto->protocol_end(); P != PE; ++P)
901        CollectInheritedProtocols(*P, Protocols);
902    }
903  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
904    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
905         PE = OP->protocol_end(); P != PE; ++P) {
906      ObjCProtocolDecl *Proto = (*P);
907      Protocols.insert(Proto);
908      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
909           PE = Proto->protocol_end(); P != PE; ++P)
910        CollectInheritedProtocols(*P, Protocols);
911    }
912  }
913}
914
915unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) {
916  unsigned count = 0;
917  // Count ivars declared in class extension.
918  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
919       CDecl = CDecl->getNextClassExtension())
920    count += CDecl->ivar_size();
921
922  // Count ivar defined in this class's implementation.  This
923  // includes synthesized ivars.
924  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
925    count += ImplDecl->ivar_size();
926
927  return count;
928}
929
930/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
931ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
932  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
933    I = ObjCImpls.find(D);
934  if (I != ObjCImpls.end())
935    return cast<ObjCImplementationDecl>(I->second);
936  return 0;
937}
938/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
939ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
940  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
941    I = ObjCImpls.find(D);
942  if (I != ObjCImpls.end())
943    return cast<ObjCCategoryImplDecl>(I->second);
944  return 0;
945}
946
947/// \brief Set the implementation of ObjCInterfaceDecl.
948void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
949                           ObjCImplementationDecl *ImplD) {
950  assert(IFaceD && ImplD && "Passed null params");
951  ObjCImpls[IFaceD] = ImplD;
952}
953/// \brief Set the implementation of ObjCCategoryDecl.
954void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
955                           ObjCCategoryImplDecl *ImplD) {
956  assert(CatD && ImplD && "Passed null params");
957  ObjCImpls[CatD] = ImplD;
958}
959
960/// \brief Allocate an uninitialized TypeSourceInfo.
961///
962/// The caller should initialize the memory held by TypeSourceInfo using
963/// the TypeLoc wrappers.
964///
965/// \param T the type that will be the basis for type source info. This type
966/// should refer to how the declarator was written in source code, not to
967/// what type semantic analysis resolved the declarator to.
968TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
969                                                 unsigned DataSize) {
970  if (!DataSize)
971    DataSize = TypeLoc::getFullDataSizeForType(T);
972  else
973    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
974           "incorrect data size provided to CreateTypeSourceInfo!");
975
976  TypeSourceInfo *TInfo =
977    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
978  new (TInfo) TypeSourceInfo(T);
979  return TInfo;
980}
981
982TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
983                                                     SourceLocation L) {
984  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
985  DI->getTypeLoc().initialize(L);
986  return DI;
987}
988
989const ASTRecordLayout &
990ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) {
991  return getObjCLayout(D, 0);
992}
993
994const ASTRecordLayout &
995ASTContext::getASTObjCImplementationLayout(const ObjCImplementationDecl *D) {
996  return getObjCLayout(D->getClassInterface(), D);
997}
998
999//===----------------------------------------------------------------------===//
1000//                   Type creation/memoization methods
1001//===----------------------------------------------------------------------===//
1002
1003QualType ASTContext::getExtQualType(const Type *TypeNode, Qualifiers Quals) {
1004  unsigned Fast = Quals.getFastQualifiers();
1005  Quals.removeFastQualifiers();
1006
1007  // Check if we've already instantiated this type.
1008  llvm::FoldingSetNodeID ID;
1009  ExtQuals::Profile(ID, TypeNode, Quals);
1010  void *InsertPos = 0;
1011  if (ExtQuals *EQ = ExtQualNodes.FindNodeOrInsertPos(ID, InsertPos)) {
1012    assert(EQ->getQualifiers() == Quals);
1013    QualType T = QualType(EQ, Fast);
1014    return T;
1015  }
1016
1017  ExtQuals *New = new (*this, TypeAlignment) ExtQuals(*this, TypeNode, Quals);
1018  ExtQualNodes.InsertNode(New, InsertPos);
1019  QualType T = QualType(New, Fast);
1020  return T;
1021}
1022
1023QualType ASTContext::getVolatileType(QualType T) {
1024  QualType CanT = getCanonicalType(T);
1025  if (CanT.isVolatileQualified()) return T;
1026
1027  QualifierCollector Quals;
1028  const Type *TypeNode = Quals.strip(T);
1029  Quals.addVolatile();
1030
1031  return getExtQualType(TypeNode, Quals);
1032}
1033
1034QualType ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) {
1035  QualType CanT = getCanonicalType(T);
1036  if (CanT.getAddressSpace() == AddressSpace)
1037    return T;
1038
1039  // If we are composing extended qualifiers together, merge together
1040  // into one ExtQuals node.
1041  QualifierCollector Quals;
1042  const Type *TypeNode = Quals.strip(T);
1043
1044  // If this type already has an address space specified, it cannot get
1045  // another one.
1046  assert(!Quals.hasAddressSpace() &&
1047         "Type cannot be in multiple addr spaces!");
1048  Quals.addAddressSpace(AddressSpace);
1049
1050  return getExtQualType(TypeNode, Quals);
1051}
1052
1053QualType ASTContext::getObjCGCQualType(QualType T,
1054                                       Qualifiers::GC GCAttr) {
1055  QualType CanT = getCanonicalType(T);
1056  if (CanT.getObjCGCAttr() == GCAttr)
1057    return T;
1058
1059  if (T->isPointerType()) {
1060    QualType Pointee = T->getAs<PointerType>()->getPointeeType();
1061    if (Pointee->isAnyPointerType()) {
1062      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1063      return getPointerType(ResultType);
1064    }
1065  }
1066
1067  // If we are composing extended qualifiers together, merge together
1068  // into one ExtQuals node.
1069  QualifierCollector Quals;
1070  const Type *TypeNode = Quals.strip(T);
1071
1072  // If this type already has an ObjCGC specified, it cannot get
1073  // another one.
1074  assert(!Quals.hasObjCGCAttr() &&
1075         "Type cannot have multiple ObjCGCs!");
1076  Quals.addObjCGCAttr(GCAttr);
1077
1078  return getExtQualType(TypeNode, Quals);
1079}
1080
1081static QualType getExtFunctionType(ASTContext& Context, QualType T,
1082                                        const FunctionType::ExtInfo &Info) {
1083  QualType ResultType;
1084  if (const PointerType *Pointer = T->getAs<PointerType>()) {
1085    QualType Pointee = Pointer->getPointeeType();
1086    ResultType = getExtFunctionType(Context, Pointee, Info);
1087    if (ResultType == Pointee)
1088      return T;
1089
1090    ResultType = Context.getPointerType(ResultType);
1091  } else if (const BlockPointerType *BlockPointer
1092                                              = T->getAs<BlockPointerType>()) {
1093    QualType Pointee = BlockPointer->getPointeeType();
1094    ResultType = getExtFunctionType(Context, Pointee, Info);
1095    if (ResultType == Pointee)
1096      return T;
1097
1098    ResultType = Context.getBlockPointerType(ResultType);
1099   } else if (const FunctionType *F = T->getAs<FunctionType>()) {
1100    if (F->getExtInfo() == Info)
1101      return T;
1102
1103    if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(F)) {
1104      ResultType = Context.getFunctionNoProtoType(FNPT->getResultType(),
1105                                                  Info);
1106    } else {
1107      const FunctionProtoType *FPT = cast<FunctionProtoType>(F);
1108      ResultType
1109        = Context.getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1110                                  FPT->getNumArgs(), FPT->isVariadic(),
1111                                  FPT->getTypeQuals(),
1112                                  FPT->hasExceptionSpec(),
1113                                  FPT->hasAnyExceptionSpec(),
1114                                  FPT->getNumExceptions(),
1115                                  FPT->exception_begin(),
1116                                  Info);
1117    }
1118  } else
1119    return T;
1120
1121  return Context.getQualifiedType(ResultType, T.getLocalQualifiers());
1122}
1123
1124QualType ASTContext::getNoReturnType(QualType T, bool AddNoReturn) {
1125  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1126  return getExtFunctionType(*this, T,
1127                                 Info.withNoReturn(AddNoReturn));
1128}
1129
1130QualType ASTContext::getCallConvType(QualType T, CallingConv CallConv) {
1131  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1132  return getExtFunctionType(*this, T,
1133                            Info.withCallingConv(CallConv));
1134}
1135
1136QualType ASTContext::getRegParmType(QualType T, unsigned RegParm) {
1137  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1138  return getExtFunctionType(*this, T,
1139                                 Info.withRegParm(RegParm));
1140}
1141
1142/// getComplexType - Return the uniqued reference to the type for a complex
1143/// number with the specified element type.
1144QualType ASTContext::getComplexType(QualType T) {
1145  // Unique pointers, to guarantee there is only one pointer of a particular
1146  // structure.
1147  llvm::FoldingSetNodeID ID;
1148  ComplexType::Profile(ID, T);
1149
1150  void *InsertPos = 0;
1151  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1152    return QualType(CT, 0);
1153
1154  // If the pointee type isn't canonical, this won't be a canonical type either,
1155  // so fill in the canonical type field.
1156  QualType Canonical;
1157  if (!T.isCanonical()) {
1158    Canonical = getComplexType(getCanonicalType(T));
1159
1160    // Get the new insert position for the node we care about.
1161    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1162    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1163  }
1164  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1165  Types.push_back(New);
1166  ComplexTypes.InsertNode(New, InsertPos);
1167  return QualType(New, 0);
1168}
1169
1170/// getPointerType - Return the uniqued reference to the type for a pointer to
1171/// the specified type.
1172QualType ASTContext::getPointerType(QualType T) {
1173  // Unique pointers, to guarantee there is only one pointer of a particular
1174  // structure.
1175  llvm::FoldingSetNodeID ID;
1176  PointerType::Profile(ID, T);
1177
1178  void *InsertPos = 0;
1179  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1180    return QualType(PT, 0);
1181
1182  // If the pointee type isn't canonical, this won't be a canonical type either,
1183  // so fill in the canonical type field.
1184  QualType Canonical;
1185  if (!T.isCanonical()) {
1186    Canonical = getPointerType(getCanonicalType(T));
1187
1188    // Get the new insert position for the node we care about.
1189    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1190    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1191  }
1192  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1193  Types.push_back(New);
1194  PointerTypes.InsertNode(New, InsertPos);
1195  return QualType(New, 0);
1196}
1197
1198/// getBlockPointerType - Return the uniqued reference to the type for
1199/// a pointer to the specified block.
1200QualType ASTContext::getBlockPointerType(QualType T) {
1201  assert(T->isFunctionType() && "block of function types only");
1202  // Unique pointers, to guarantee there is only one block of a particular
1203  // structure.
1204  llvm::FoldingSetNodeID ID;
1205  BlockPointerType::Profile(ID, T);
1206
1207  void *InsertPos = 0;
1208  if (BlockPointerType *PT =
1209        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1210    return QualType(PT, 0);
1211
1212  // If the block pointee type isn't canonical, this won't be a canonical
1213  // type either so fill in the canonical type field.
1214  QualType Canonical;
1215  if (!T.isCanonical()) {
1216    Canonical = getBlockPointerType(getCanonicalType(T));
1217
1218    // Get the new insert position for the node we care about.
1219    BlockPointerType *NewIP =
1220      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1221    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1222  }
1223  BlockPointerType *New
1224    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1225  Types.push_back(New);
1226  BlockPointerTypes.InsertNode(New, InsertPos);
1227  return QualType(New, 0);
1228}
1229
1230/// getLValueReferenceType - Return the uniqued reference to the type for an
1231/// lvalue reference to the specified type.
1232QualType ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) {
1233  // Unique pointers, to guarantee there is only one pointer of a particular
1234  // structure.
1235  llvm::FoldingSetNodeID ID;
1236  ReferenceType::Profile(ID, T, SpelledAsLValue);
1237
1238  void *InsertPos = 0;
1239  if (LValueReferenceType *RT =
1240        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1241    return QualType(RT, 0);
1242
1243  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1244
1245  // If the referencee type isn't canonical, this won't be a canonical type
1246  // either, so fill in the canonical type field.
1247  QualType Canonical;
1248  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1249    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1250    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1251
1252    // Get the new insert position for the node we care about.
1253    LValueReferenceType *NewIP =
1254      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1255    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1256  }
1257
1258  LValueReferenceType *New
1259    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1260                                                     SpelledAsLValue);
1261  Types.push_back(New);
1262  LValueReferenceTypes.InsertNode(New, InsertPos);
1263
1264  return QualType(New, 0);
1265}
1266
1267/// getRValueReferenceType - Return the uniqued reference to the type for an
1268/// rvalue reference to the specified type.
1269QualType ASTContext::getRValueReferenceType(QualType T) {
1270  // Unique pointers, to guarantee there is only one pointer of a particular
1271  // structure.
1272  llvm::FoldingSetNodeID ID;
1273  ReferenceType::Profile(ID, T, false);
1274
1275  void *InsertPos = 0;
1276  if (RValueReferenceType *RT =
1277        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1278    return QualType(RT, 0);
1279
1280  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1281
1282  // If the referencee type isn't canonical, this won't be a canonical type
1283  // either, so fill in the canonical type field.
1284  QualType Canonical;
1285  if (InnerRef || !T.isCanonical()) {
1286    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1287    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1288
1289    // Get the new insert position for the node we care about.
1290    RValueReferenceType *NewIP =
1291      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1292    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1293  }
1294
1295  RValueReferenceType *New
1296    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1297  Types.push_back(New);
1298  RValueReferenceTypes.InsertNode(New, InsertPos);
1299  return QualType(New, 0);
1300}
1301
1302/// getMemberPointerType - Return the uniqued reference to the type for a
1303/// member pointer to the specified type, in the specified class.
1304QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) {
1305  // Unique pointers, to guarantee there is only one pointer of a particular
1306  // structure.
1307  llvm::FoldingSetNodeID ID;
1308  MemberPointerType::Profile(ID, T, Cls);
1309
1310  void *InsertPos = 0;
1311  if (MemberPointerType *PT =
1312      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1313    return QualType(PT, 0);
1314
1315  // If the pointee or class type isn't canonical, this won't be a canonical
1316  // type either, so fill in the canonical type field.
1317  QualType Canonical;
1318  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1319    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1320
1321    // Get the new insert position for the node we care about.
1322    MemberPointerType *NewIP =
1323      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1324    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1325  }
1326  MemberPointerType *New
1327    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1328  Types.push_back(New);
1329  MemberPointerTypes.InsertNode(New, InsertPos);
1330  return QualType(New, 0);
1331}
1332
1333/// getConstantArrayType - Return the unique reference to the type for an
1334/// array of the specified element type.
1335QualType ASTContext::getConstantArrayType(QualType EltTy,
1336                                          const llvm::APInt &ArySizeIn,
1337                                          ArrayType::ArraySizeModifier ASM,
1338                                          unsigned EltTypeQuals) {
1339  assert((EltTy->isDependentType() ||
1340          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1341         "Constant array of VLAs is illegal!");
1342
1343  // Convert the array size into a canonical width matching the pointer size for
1344  // the target.
1345  llvm::APInt ArySize(ArySizeIn);
1346  ArySize.zextOrTrunc(Target.getPointerWidth(EltTy.getAddressSpace()));
1347
1348  llvm::FoldingSetNodeID ID;
1349  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, EltTypeQuals);
1350
1351  void *InsertPos = 0;
1352  if (ConstantArrayType *ATP =
1353      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1354    return QualType(ATP, 0);
1355
1356  // If the element type isn't canonical, this won't be a canonical type either,
1357  // so fill in the canonical type field.
1358  QualType Canonical;
1359  if (!EltTy.isCanonical()) {
1360    Canonical = getConstantArrayType(getCanonicalType(EltTy), ArySize,
1361                                     ASM, EltTypeQuals);
1362    // Get the new insert position for the node we care about.
1363    ConstantArrayType *NewIP =
1364      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1365    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1366  }
1367
1368  ConstantArrayType *New = new(*this,TypeAlignment)
1369    ConstantArrayType(EltTy, Canonical, ArySize, ASM, EltTypeQuals);
1370  ConstantArrayTypes.InsertNode(New, InsertPos);
1371  Types.push_back(New);
1372  return QualType(New, 0);
1373}
1374
1375/// getVariableArrayType - Returns a non-unique reference to the type for a
1376/// variable array of the specified element type.
1377QualType ASTContext::getVariableArrayType(QualType EltTy,
1378                                          Expr *NumElts,
1379                                          ArrayType::ArraySizeModifier ASM,
1380                                          unsigned EltTypeQuals,
1381                                          SourceRange Brackets) {
1382  // Since we don't unique expressions, it isn't possible to unique VLA's
1383  // that have an expression provided for their size.
1384  QualType CanonType;
1385
1386  if (!EltTy.isCanonical()) {
1387    if (NumElts)
1388      NumElts->Retain();
1389    CanonType = getVariableArrayType(getCanonicalType(EltTy), NumElts, ASM,
1390                                     EltTypeQuals, Brackets);
1391  }
1392
1393  VariableArrayType *New = new(*this, TypeAlignment)
1394    VariableArrayType(EltTy, CanonType, NumElts, ASM, EltTypeQuals, Brackets);
1395
1396  VariableArrayTypes.push_back(New);
1397  Types.push_back(New);
1398  return QualType(New, 0);
1399}
1400
1401/// getDependentSizedArrayType - Returns a non-unique reference to
1402/// the type for a dependently-sized array of the specified element
1403/// type.
1404QualType ASTContext::getDependentSizedArrayType(QualType EltTy,
1405                                                Expr *NumElts,
1406                                                ArrayType::ArraySizeModifier ASM,
1407                                                unsigned EltTypeQuals,
1408                                                SourceRange Brackets) {
1409  assert((!NumElts || NumElts->isTypeDependent() ||
1410          NumElts->isValueDependent()) &&
1411         "Size must be type- or value-dependent!");
1412
1413  void *InsertPos = 0;
1414  DependentSizedArrayType *Canon = 0;
1415  llvm::FoldingSetNodeID ID;
1416
1417  if (NumElts) {
1418    // Dependently-sized array types that do not have a specified
1419    // number of elements will have their sizes deduced from an
1420    // initializer.
1421    DependentSizedArrayType::Profile(ID, *this, getCanonicalType(EltTy), ASM,
1422                                     EltTypeQuals, NumElts);
1423
1424    Canon = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1425  }
1426
1427  DependentSizedArrayType *New;
1428  if (Canon) {
1429    // We already have a canonical version of this array type; use it as
1430    // the canonical type for a newly-built type.
1431    New = new (*this, TypeAlignment)
1432      DependentSizedArrayType(*this, EltTy, QualType(Canon, 0),
1433                              NumElts, ASM, EltTypeQuals, Brackets);
1434  } else {
1435    QualType CanonEltTy = getCanonicalType(EltTy);
1436    if (CanonEltTy == EltTy) {
1437      New = new (*this, TypeAlignment)
1438        DependentSizedArrayType(*this, EltTy, QualType(),
1439                                NumElts, ASM, EltTypeQuals, Brackets);
1440
1441      if (NumElts) {
1442        DependentSizedArrayType *CanonCheck
1443          = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1444        assert(!CanonCheck && "Dependent-sized canonical array type broken");
1445        (void)CanonCheck;
1446        DependentSizedArrayTypes.InsertNode(New, InsertPos);
1447      }
1448    } else {
1449      QualType Canon = getDependentSizedArrayType(CanonEltTy, NumElts,
1450                                                  ASM, EltTypeQuals,
1451                                                  SourceRange());
1452      New = new (*this, TypeAlignment)
1453        DependentSizedArrayType(*this, EltTy, Canon,
1454                                NumElts, ASM, EltTypeQuals, Brackets);
1455    }
1456  }
1457
1458  Types.push_back(New);
1459  return QualType(New, 0);
1460}
1461
1462QualType ASTContext::getIncompleteArrayType(QualType EltTy,
1463                                            ArrayType::ArraySizeModifier ASM,
1464                                            unsigned EltTypeQuals) {
1465  llvm::FoldingSetNodeID ID;
1466  IncompleteArrayType::Profile(ID, EltTy, ASM, EltTypeQuals);
1467
1468  void *InsertPos = 0;
1469  if (IncompleteArrayType *ATP =
1470       IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1471    return QualType(ATP, 0);
1472
1473  // If the element type isn't canonical, this won't be a canonical type
1474  // either, so fill in the canonical type field.
1475  QualType Canonical;
1476
1477  if (!EltTy.isCanonical()) {
1478    Canonical = getIncompleteArrayType(getCanonicalType(EltTy),
1479                                       ASM, EltTypeQuals);
1480
1481    // Get the new insert position for the node we care about.
1482    IncompleteArrayType *NewIP =
1483      IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1484    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1485  }
1486
1487  IncompleteArrayType *New = new (*this, TypeAlignment)
1488    IncompleteArrayType(EltTy, Canonical, ASM, EltTypeQuals);
1489
1490  IncompleteArrayTypes.InsertNode(New, InsertPos);
1491  Types.push_back(New);
1492  return QualType(New, 0);
1493}
1494
1495/// getVectorType - Return the unique reference to a vector type of
1496/// the specified element type and size. VectorType must be a built-in type.
1497QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1498    VectorType::AltiVecSpecific AltiVecSpec) {
1499  BuiltinType *baseType;
1500
1501  baseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1502  assert(baseType != 0 && "getVectorType(): Expecting a built-in type");
1503
1504  // Check if we've already instantiated a vector of this type.
1505  llvm::FoldingSetNodeID ID;
1506  VectorType::Profile(ID, vecType, NumElts, Type::Vector, AltiVecSpec);
1507
1508  void *InsertPos = 0;
1509  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1510    return QualType(VTP, 0);
1511
1512  // If the element type isn't canonical, this won't be a canonical type either,
1513  // so fill in the canonical type field.
1514  QualType Canonical;
1515  if (!vecType.isCanonical()) {
1516    Canonical = getVectorType(getCanonicalType(vecType), NumElts,
1517      VectorType::NotAltiVec);
1518
1519    // Get the new insert position for the node we care about.
1520    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1521    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1522  }
1523  VectorType *New = new (*this, TypeAlignment)
1524    VectorType(vecType, NumElts, Canonical, AltiVecSpec);
1525  VectorTypes.InsertNode(New, InsertPos);
1526  Types.push_back(New);
1527  return QualType(New, 0);
1528}
1529
1530/// getExtVectorType - Return the unique reference to an extended vector type of
1531/// the specified element type and size. VectorType must be a built-in type.
1532QualType ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) {
1533  BuiltinType *baseType;
1534
1535  baseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1536  assert(baseType != 0 && "getExtVectorType(): Expecting a built-in type");
1537
1538  // Check if we've already instantiated a vector of this type.
1539  llvm::FoldingSetNodeID ID;
1540  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1541                      VectorType::NotAltiVec);
1542  void *InsertPos = 0;
1543  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1544    return QualType(VTP, 0);
1545
1546  // If the element type isn't canonical, this won't be a canonical type either,
1547  // so fill in the canonical type field.
1548  QualType Canonical;
1549  if (!vecType.isCanonical()) {
1550    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
1551
1552    // Get the new insert position for the node we care about.
1553    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1554    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1555  }
1556  ExtVectorType *New = new (*this, TypeAlignment)
1557    ExtVectorType(vecType, NumElts, Canonical);
1558  VectorTypes.InsertNode(New, InsertPos);
1559  Types.push_back(New);
1560  return QualType(New, 0);
1561}
1562
1563QualType ASTContext::getDependentSizedExtVectorType(QualType vecType,
1564                                                    Expr *SizeExpr,
1565                                                    SourceLocation AttrLoc) {
1566  llvm::FoldingSetNodeID ID;
1567  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
1568                                       SizeExpr);
1569
1570  void *InsertPos = 0;
1571  DependentSizedExtVectorType *Canon
1572    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1573  DependentSizedExtVectorType *New;
1574  if (Canon) {
1575    // We already have a canonical version of this array type; use it as
1576    // the canonical type for a newly-built type.
1577    New = new (*this, TypeAlignment)
1578      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
1579                                  SizeExpr, AttrLoc);
1580  } else {
1581    QualType CanonVecTy = getCanonicalType(vecType);
1582    if (CanonVecTy == vecType) {
1583      New = new (*this, TypeAlignment)
1584        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
1585                                    AttrLoc);
1586
1587      DependentSizedExtVectorType *CanonCheck
1588        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1589      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
1590      (void)CanonCheck;
1591      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
1592    } else {
1593      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
1594                                                      SourceLocation());
1595      New = new (*this, TypeAlignment)
1596        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
1597    }
1598  }
1599
1600  Types.push_back(New);
1601  return QualType(New, 0);
1602}
1603
1604/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
1605///
1606QualType ASTContext::getFunctionNoProtoType(QualType ResultTy,
1607                                            const FunctionType::ExtInfo &Info) {
1608  const CallingConv CallConv = Info.getCC();
1609  // Unique functions, to guarantee there is only one function of a particular
1610  // structure.
1611  llvm::FoldingSetNodeID ID;
1612  FunctionNoProtoType::Profile(ID, ResultTy, Info);
1613
1614  void *InsertPos = 0;
1615  if (FunctionNoProtoType *FT =
1616        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1617    return QualType(FT, 0);
1618
1619  QualType Canonical;
1620  if (!ResultTy.isCanonical() ||
1621      getCanonicalCallConv(CallConv) != CallConv) {
1622    Canonical =
1623      getFunctionNoProtoType(getCanonicalType(ResultTy),
1624                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1625
1626    // Get the new insert position for the node we care about.
1627    FunctionNoProtoType *NewIP =
1628      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1629    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1630  }
1631
1632  FunctionNoProtoType *New = new (*this, TypeAlignment)
1633    FunctionNoProtoType(ResultTy, Canonical, Info);
1634  Types.push_back(New);
1635  FunctionNoProtoTypes.InsertNode(New, InsertPos);
1636  return QualType(New, 0);
1637}
1638
1639/// getFunctionType - Return a normal function type with a typed argument
1640/// list.  isVariadic indicates whether the argument list includes '...'.
1641QualType ASTContext::getFunctionType(QualType ResultTy,const QualType *ArgArray,
1642                                     unsigned NumArgs, bool isVariadic,
1643                                     unsigned TypeQuals, bool hasExceptionSpec,
1644                                     bool hasAnyExceptionSpec, unsigned NumExs,
1645                                     const QualType *ExArray,
1646                                     const FunctionType::ExtInfo &Info) {
1647  const CallingConv CallConv= Info.getCC();
1648  // Unique functions, to guarantee there is only one function of a particular
1649  // structure.
1650  llvm::FoldingSetNodeID ID;
1651  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, isVariadic,
1652                             TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1653                             NumExs, ExArray, Info);
1654
1655  void *InsertPos = 0;
1656  if (FunctionProtoType *FTP =
1657        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1658    return QualType(FTP, 0);
1659
1660  // Determine whether the type being created is already canonical or not.
1661  bool isCanonical = !hasExceptionSpec && ResultTy.isCanonical();
1662  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
1663    if (!ArgArray[i].isCanonicalAsParam())
1664      isCanonical = false;
1665
1666  // If this type isn't canonical, get the canonical version of it.
1667  // The exception spec is not part of the canonical type.
1668  QualType Canonical;
1669  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
1670    llvm::SmallVector<QualType, 16> CanonicalArgs;
1671    CanonicalArgs.reserve(NumArgs);
1672    for (unsigned i = 0; i != NumArgs; ++i)
1673      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
1674
1675    Canonical = getFunctionType(getCanonicalType(ResultTy),
1676                                CanonicalArgs.data(), NumArgs,
1677                                isVariadic, TypeQuals, false,
1678                                false, 0, 0,
1679                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1680
1681    // Get the new insert position for the node we care about.
1682    FunctionProtoType *NewIP =
1683      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1684    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1685  }
1686
1687  // FunctionProtoType objects are allocated with extra bytes after them
1688  // for two variable size arrays (for parameter and exception types) at the
1689  // end of them.
1690  FunctionProtoType *FTP =
1691    (FunctionProtoType*)Allocate(sizeof(FunctionProtoType) +
1692                                 NumArgs*sizeof(QualType) +
1693                                 NumExs*sizeof(QualType), TypeAlignment);
1694  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, isVariadic,
1695                              TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1696                              ExArray, NumExs, Canonical, Info);
1697  Types.push_back(FTP);
1698  FunctionProtoTypes.InsertNode(FTP, InsertPos);
1699  return QualType(FTP, 0);
1700}
1701
1702#ifndef NDEBUG
1703static bool NeedsInjectedClassNameType(const RecordDecl *D) {
1704  if (!isa<CXXRecordDecl>(D)) return false;
1705  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
1706  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
1707    return true;
1708  if (RD->getDescribedClassTemplate() &&
1709      !isa<ClassTemplateSpecializationDecl>(RD))
1710    return true;
1711  return false;
1712}
1713#endif
1714
1715/// getInjectedClassNameType - Return the unique reference to the
1716/// injected class name type for the specified templated declaration.
1717QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
1718                                              QualType TST) {
1719  assert(NeedsInjectedClassNameType(Decl));
1720  if (Decl->TypeForDecl) {
1721    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1722  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDeclaration()) {
1723    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
1724    Decl->TypeForDecl = PrevDecl->TypeForDecl;
1725    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1726  } else {
1727    Decl->TypeForDecl =
1728      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
1729    Types.push_back(Decl->TypeForDecl);
1730  }
1731  return QualType(Decl->TypeForDecl, 0);
1732}
1733
1734/// getTypeDeclType - Return the unique reference to the type for the
1735/// specified type declaration.
1736QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) {
1737  assert(Decl && "Passed null for Decl param");
1738  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
1739
1740  if (const TypedefDecl *Typedef = dyn_cast<TypedefDecl>(Decl))
1741    return getTypedefType(Typedef);
1742
1743  assert(!isa<TemplateTypeParmDecl>(Decl) &&
1744         "Template type parameter types are always available.");
1745
1746  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
1747    assert(!Record->getPreviousDeclaration() &&
1748           "struct/union has previous declaration");
1749    assert(!NeedsInjectedClassNameType(Record));
1750    return getRecordType(Record);
1751  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
1752    assert(!Enum->getPreviousDeclaration() &&
1753           "enum has previous declaration");
1754    return getEnumType(Enum);
1755  } else if (const UnresolvedUsingTypenameDecl *Using =
1756               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
1757    Decl->TypeForDecl = new (*this, TypeAlignment) UnresolvedUsingType(Using);
1758  } else
1759    llvm_unreachable("TypeDecl without a type?");
1760
1761  Types.push_back(Decl->TypeForDecl);
1762  return QualType(Decl->TypeForDecl, 0);
1763}
1764
1765/// getTypedefType - Return the unique reference to the type for the
1766/// specified typename decl.
1767QualType
1768ASTContext::getTypedefType(const TypedefDecl *Decl, QualType Canonical) {
1769  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1770
1771  if (Canonical.isNull())
1772    Canonical = getCanonicalType(Decl->getUnderlyingType());
1773  Decl->TypeForDecl = new(*this, TypeAlignment)
1774    TypedefType(Type::Typedef, Decl, Canonical);
1775  Types.push_back(Decl->TypeForDecl);
1776  return QualType(Decl->TypeForDecl, 0);
1777}
1778
1779QualType ASTContext::getRecordType(const RecordDecl *Decl) {
1780  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1781
1782  if (const RecordDecl *PrevDecl = Decl->getPreviousDeclaration())
1783    if (PrevDecl->TypeForDecl)
1784      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1785
1786  Decl->TypeForDecl = new (*this, TypeAlignment) RecordType(Decl);
1787  Types.push_back(Decl->TypeForDecl);
1788  return QualType(Decl->TypeForDecl, 0);
1789}
1790
1791QualType ASTContext::getEnumType(const EnumDecl *Decl) {
1792  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1793
1794  if (const EnumDecl *PrevDecl = Decl->getPreviousDeclaration())
1795    if (PrevDecl->TypeForDecl)
1796      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1797
1798  Decl->TypeForDecl = new (*this, TypeAlignment) EnumType(Decl);
1799  Types.push_back(Decl->TypeForDecl);
1800  return QualType(Decl->TypeForDecl, 0);
1801}
1802
1803/// \brief Retrieve a substitution-result type.
1804QualType
1805ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
1806                                         QualType Replacement) {
1807  assert(Replacement.isCanonical()
1808         && "replacement types must always be canonical");
1809
1810  llvm::FoldingSetNodeID ID;
1811  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
1812  void *InsertPos = 0;
1813  SubstTemplateTypeParmType *SubstParm
1814    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1815
1816  if (!SubstParm) {
1817    SubstParm = new (*this, TypeAlignment)
1818      SubstTemplateTypeParmType(Parm, Replacement);
1819    Types.push_back(SubstParm);
1820    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
1821  }
1822
1823  return QualType(SubstParm, 0);
1824}
1825
1826/// \brief Retrieve the template type parameter type for a template
1827/// parameter or parameter pack with the given depth, index, and (optionally)
1828/// name.
1829QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
1830                                             bool ParameterPack,
1831                                             IdentifierInfo *Name) {
1832  llvm::FoldingSetNodeID ID;
1833  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, Name);
1834  void *InsertPos = 0;
1835  TemplateTypeParmType *TypeParm
1836    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1837
1838  if (TypeParm)
1839    return QualType(TypeParm, 0);
1840
1841  if (Name) {
1842    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
1843    TypeParm = new (*this, TypeAlignment)
1844      TemplateTypeParmType(Depth, Index, ParameterPack, Name, Canon);
1845
1846    TemplateTypeParmType *TypeCheck
1847      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1848    assert(!TypeCheck && "Template type parameter canonical type broken");
1849    (void)TypeCheck;
1850  } else
1851    TypeParm = new (*this, TypeAlignment)
1852      TemplateTypeParmType(Depth, Index, ParameterPack);
1853
1854  Types.push_back(TypeParm);
1855  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
1856
1857  return QualType(TypeParm, 0);
1858}
1859
1860TypeSourceInfo *
1861ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
1862                                              SourceLocation NameLoc,
1863                                        const TemplateArgumentListInfo &Args,
1864                                              QualType CanonType) {
1865  QualType TST = getTemplateSpecializationType(Name, Args, CanonType);
1866
1867  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
1868  TemplateSpecializationTypeLoc TL
1869    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
1870  TL.setTemplateNameLoc(NameLoc);
1871  TL.setLAngleLoc(Args.getLAngleLoc());
1872  TL.setRAngleLoc(Args.getRAngleLoc());
1873  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
1874    TL.setArgLocInfo(i, Args[i].getLocInfo());
1875  return DI;
1876}
1877
1878QualType
1879ASTContext::getTemplateSpecializationType(TemplateName Template,
1880                                          const TemplateArgumentListInfo &Args,
1881                                          QualType Canon) {
1882  unsigned NumArgs = Args.size();
1883
1884  llvm::SmallVector<TemplateArgument, 4> ArgVec;
1885  ArgVec.reserve(NumArgs);
1886  for (unsigned i = 0; i != NumArgs; ++i)
1887    ArgVec.push_back(Args[i].getArgument());
1888
1889  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
1890                                       Canon);
1891}
1892
1893QualType
1894ASTContext::getTemplateSpecializationType(TemplateName Template,
1895                                          const TemplateArgument *Args,
1896                                          unsigned NumArgs,
1897                                          QualType Canon) {
1898  if (!Canon.isNull())
1899    Canon = getCanonicalType(Canon);
1900  else
1901    Canon = getCanonicalTemplateSpecializationType(Template, Args, NumArgs);
1902
1903  // Allocate the (non-canonical) template specialization type, but don't
1904  // try to unique it: these types typically have location information that
1905  // we don't unique and don't want to lose.
1906  void *Mem = Allocate((sizeof(TemplateSpecializationType) +
1907                        sizeof(TemplateArgument) * NumArgs),
1908                       TypeAlignment);
1909  TemplateSpecializationType *Spec
1910    = new (Mem) TemplateSpecializationType(Template,
1911                                           Args, NumArgs,
1912                                           Canon);
1913
1914  Types.push_back(Spec);
1915  return QualType(Spec, 0);
1916}
1917
1918QualType
1919ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
1920                                                   const TemplateArgument *Args,
1921                                                   unsigned NumArgs) {
1922  // Build the canonical template specialization type.
1923  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
1924  llvm::SmallVector<TemplateArgument, 4> CanonArgs;
1925  CanonArgs.reserve(NumArgs);
1926  for (unsigned I = 0; I != NumArgs; ++I)
1927    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
1928
1929  // Determine whether this canonical template specialization type already
1930  // exists.
1931  llvm::FoldingSetNodeID ID;
1932  TemplateSpecializationType::Profile(ID, CanonTemplate,
1933                                      CanonArgs.data(), NumArgs, *this);
1934
1935  void *InsertPos = 0;
1936  TemplateSpecializationType *Spec
1937    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
1938
1939  if (!Spec) {
1940    // Allocate a new canonical template specialization type.
1941    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
1942                          sizeof(TemplateArgument) * NumArgs),
1943                         TypeAlignment);
1944    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
1945                                                CanonArgs.data(), NumArgs,
1946                                                QualType());
1947    Types.push_back(Spec);
1948    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
1949  }
1950
1951  assert(Spec->isDependentType() &&
1952         "Non-dependent template-id type must have a canonical type");
1953  return QualType(Spec, 0);
1954}
1955
1956QualType
1957ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
1958                              NestedNameSpecifier *NNS,
1959                              QualType NamedType) {
1960  llvm::FoldingSetNodeID ID;
1961  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
1962
1963  void *InsertPos = 0;
1964  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
1965  if (T)
1966    return QualType(T, 0);
1967
1968  QualType Canon = NamedType;
1969  if (!Canon.isCanonical()) {
1970    Canon = getCanonicalType(NamedType);
1971    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
1972    assert(!CheckT && "Elaborated canonical type broken");
1973    (void)CheckT;
1974  }
1975
1976  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
1977  Types.push_back(T);
1978  ElaboratedTypes.InsertNode(T, InsertPos);
1979  return QualType(T, 0);
1980}
1981
1982QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
1983                                          NestedNameSpecifier *NNS,
1984                                          const IdentifierInfo *Name,
1985                                          QualType Canon) {
1986  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
1987
1988  if (Canon.isNull()) {
1989    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
1990    ElaboratedTypeKeyword CanonKeyword = Keyword;
1991    if (Keyword == ETK_None)
1992      CanonKeyword = ETK_Typename;
1993
1994    if (CanonNNS != NNS || CanonKeyword != Keyword)
1995      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
1996  }
1997
1998  llvm::FoldingSetNodeID ID;
1999  DependentNameType::Profile(ID, Keyword, NNS, Name);
2000
2001  void *InsertPos = 0;
2002  DependentNameType *T
2003    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2004  if (T)
2005    return QualType(T, 0);
2006
2007  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2008  Types.push_back(T);
2009  DependentNameTypes.InsertNode(T, InsertPos);
2010  return QualType(T, 0);
2011}
2012
2013QualType
2014ASTContext::getDependentTemplateSpecializationType(
2015                                 ElaboratedTypeKeyword Keyword,
2016                                 NestedNameSpecifier *NNS,
2017                                 const IdentifierInfo *Name,
2018                                 const TemplateArgumentListInfo &Args) {
2019  // TODO: avoid this copy
2020  llvm::SmallVector<TemplateArgument, 16> ArgCopy;
2021  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2022    ArgCopy.push_back(Args[I].getArgument());
2023  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2024                                                ArgCopy.size(),
2025                                                ArgCopy.data());
2026}
2027
2028QualType
2029ASTContext::getDependentTemplateSpecializationType(
2030                                 ElaboratedTypeKeyword Keyword,
2031                                 NestedNameSpecifier *NNS,
2032                                 const IdentifierInfo *Name,
2033                                 unsigned NumArgs,
2034                                 const TemplateArgument *Args) {
2035  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2036
2037  llvm::FoldingSetNodeID ID;
2038  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2039                                               Name, NumArgs, Args);
2040
2041  void *InsertPos = 0;
2042  DependentTemplateSpecializationType *T
2043    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2044  if (T)
2045    return QualType(T, 0);
2046
2047  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2048
2049  ElaboratedTypeKeyword CanonKeyword = Keyword;
2050  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2051
2052  bool AnyNonCanonArgs = false;
2053  llvm::SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2054  for (unsigned I = 0; I != NumArgs; ++I) {
2055    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2056    if (!CanonArgs[I].structurallyEquals(Args[I]))
2057      AnyNonCanonArgs = true;
2058  }
2059
2060  QualType Canon;
2061  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2062    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2063                                                   Name, NumArgs,
2064                                                   CanonArgs.data());
2065
2066    // Find the insert position again.
2067    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2068  }
2069
2070  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2071                        sizeof(TemplateArgument) * NumArgs),
2072                       TypeAlignment);
2073  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2074                                                    Name, NumArgs, Args, Canon);
2075  Types.push_back(T);
2076  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2077  return QualType(T, 0);
2078}
2079
2080/// CmpProtocolNames - Comparison predicate for sorting protocols
2081/// alphabetically.
2082static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2083                            const ObjCProtocolDecl *RHS) {
2084  return LHS->getDeclName() < RHS->getDeclName();
2085}
2086
2087static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2088                                unsigned NumProtocols) {
2089  if (NumProtocols == 0) return true;
2090
2091  for (unsigned i = 1; i != NumProtocols; ++i)
2092    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]))
2093      return false;
2094  return true;
2095}
2096
2097static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2098                                   unsigned &NumProtocols) {
2099  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2100
2101  // Sort protocols, keyed by name.
2102  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2103
2104  // Remove duplicates.
2105  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2106  NumProtocols = ProtocolsEnd-Protocols;
2107}
2108
2109QualType ASTContext::getObjCObjectType(QualType BaseType,
2110                                       ObjCProtocolDecl * const *Protocols,
2111                                       unsigned NumProtocols) {
2112  // If the base type is an interface and there aren't any protocols
2113  // to add, then the interface type will do just fine.
2114  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2115    return BaseType;
2116
2117  // Look in the folding set for an existing type.
2118  llvm::FoldingSetNodeID ID;
2119  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2120  void *InsertPos = 0;
2121  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2122    return QualType(QT, 0);
2123
2124  // Build the canonical type, which has the canonical base type and
2125  // a sorted-and-uniqued list of protocols.
2126  QualType Canonical;
2127  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2128  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2129    if (!ProtocolsSorted) {
2130      llvm::SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2131                                                     Protocols + NumProtocols);
2132      unsigned UniqueCount = NumProtocols;
2133
2134      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2135      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2136                                    &Sorted[0], UniqueCount);
2137    } else {
2138      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2139                                    Protocols, NumProtocols);
2140    }
2141
2142    // Regenerate InsertPos.
2143    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2144  }
2145
2146  unsigned Size = sizeof(ObjCObjectTypeImpl);
2147  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2148  void *Mem = Allocate(Size, TypeAlignment);
2149  ObjCObjectTypeImpl *T =
2150    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2151
2152  Types.push_back(T);
2153  ObjCObjectTypes.InsertNode(T, InsertPos);
2154  return QualType(T, 0);
2155}
2156
2157/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2158/// the given object type.
2159QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) {
2160  llvm::FoldingSetNodeID ID;
2161  ObjCObjectPointerType::Profile(ID, ObjectT);
2162
2163  void *InsertPos = 0;
2164  if (ObjCObjectPointerType *QT =
2165              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2166    return QualType(QT, 0);
2167
2168  // Find the canonical object type.
2169  QualType Canonical;
2170  if (!ObjectT.isCanonical()) {
2171    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2172
2173    // Regenerate InsertPos.
2174    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2175  }
2176
2177  // No match.
2178  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2179  ObjCObjectPointerType *QType =
2180    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2181
2182  Types.push_back(QType);
2183  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2184  return QualType(QType, 0);
2185}
2186
2187/// getObjCInterfaceType - Return the unique reference to the type for the
2188/// specified ObjC interface decl. The list of protocols is optional.
2189QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl) {
2190  if (Decl->TypeForDecl)
2191    return QualType(Decl->TypeForDecl, 0);
2192
2193  // FIXME: redeclarations?
2194  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2195  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2196  Decl->TypeForDecl = T;
2197  Types.push_back(T);
2198  return QualType(T, 0);
2199}
2200
2201/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2202/// TypeOfExprType AST's (since expression's are never shared). For example,
2203/// multiple declarations that refer to "typeof(x)" all contain different
2204/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2205/// on canonical type's (which are always unique).
2206QualType ASTContext::getTypeOfExprType(Expr *tofExpr) {
2207  TypeOfExprType *toe;
2208  if (tofExpr->isTypeDependent()) {
2209    llvm::FoldingSetNodeID ID;
2210    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2211
2212    void *InsertPos = 0;
2213    DependentTypeOfExprType *Canon
2214      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2215    if (Canon) {
2216      // We already have a "canonical" version of an identical, dependent
2217      // typeof(expr) type. Use that as our canonical type.
2218      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2219                                          QualType((TypeOfExprType*)Canon, 0));
2220    }
2221    else {
2222      // Build a new, canonical typeof(expr) type.
2223      Canon
2224        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2225      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2226      toe = Canon;
2227    }
2228  } else {
2229    QualType Canonical = getCanonicalType(tofExpr->getType());
2230    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2231  }
2232  Types.push_back(toe);
2233  return QualType(toe, 0);
2234}
2235
2236/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2237/// TypeOfType AST's. The only motivation to unique these nodes would be
2238/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2239/// an issue. This doesn't effect the type checker, since it operates
2240/// on canonical type's (which are always unique).
2241QualType ASTContext::getTypeOfType(QualType tofType) {
2242  QualType Canonical = getCanonicalType(tofType);
2243  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2244  Types.push_back(tot);
2245  return QualType(tot, 0);
2246}
2247
2248/// getDecltypeForExpr - Given an expr, will return the decltype for that
2249/// expression, according to the rules in C++0x [dcl.type.simple]p4
2250static QualType getDecltypeForExpr(const Expr *e, ASTContext &Context) {
2251  if (e->isTypeDependent())
2252    return Context.DependentTy;
2253
2254  // If e is an id expression or a class member access, decltype(e) is defined
2255  // as the type of the entity named by e.
2256  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2257    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2258      return VD->getType();
2259  }
2260  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2261    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2262      return FD->getType();
2263  }
2264  // If e is a function call or an invocation of an overloaded operator,
2265  // (parentheses around e are ignored), decltype(e) is defined as the
2266  // return type of that function.
2267  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2268    return CE->getCallReturnType();
2269
2270  QualType T = e->getType();
2271
2272  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2273  // defined as T&, otherwise decltype(e) is defined as T.
2274  if (e->isLvalue(Context) == Expr::LV_Valid)
2275    T = Context.getLValueReferenceType(T);
2276
2277  return T;
2278}
2279
2280/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2281/// DecltypeType AST's. The only motivation to unique these nodes would be
2282/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2283/// an issue. This doesn't effect the type checker, since it operates
2284/// on canonical type's (which are always unique).
2285QualType ASTContext::getDecltypeType(Expr *e) {
2286  DecltypeType *dt;
2287  if (e->isTypeDependent()) {
2288    llvm::FoldingSetNodeID ID;
2289    DependentDecltypeType::Profile(ID, *this, e);
2290
2291    void *InsertPos = 0;
2292    DependentDecltypeType *Canon
2293      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2294    if (Canon) {
2295      // We already have a "canonical" version of an equivalent, dependent
2296      // decltype type. Use that as our canonical type.
2297      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2298                                       QualType((DecltypeType*)Canon, 0));
2299    }
2300    else {
2301      // Build a new, canonical typeof(expr) type.
2302      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2303      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2304      dt = Canon;
2305    }
2306  } else {
2307    QualType T = getDecltypeForExpr(e, *this);
2308    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2309  }
2310  Types.push_back(dt);
2311  return QualType(dt, 0);
2312}
2313
2314/// getTagDeclType - Return the unique reference to the type for the
2315/// specified TagDecl (struct/union/class/enum) decl.
2316QualType ASTContext::getTagDeclType(const TagDecl *Decl) {
2317  assert (Decl);
2318  // FIXME: What is the design on getTagDeclType when it requires casting
2319  // away const?  mutable?
2320  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2321}
2322
2323/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2324/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2325/// needs to agree with the definition in <stddef.h>.
2326CanQualType ASTContext::getSizeType() const {
2327  return getFromTargetType(Target.getSizeType());
2328}
2329
2330/// getSignedWCharType - Return the type of "signed wchar_t".
2331/// Used when in C++, as a GCC extension.
2332QualType ASTContext::getSignedWCharType() const {
2333  // FIXME: derive from "Target" ?
2334  return WCharTy;
2335}
2336
2337/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
2338/// Used when in C++, as a GCC extension.
2339QualType ASTContext::getUnsignedWCharType() const {
2340  // FIXME: derive from "Target" ?
2341  return UnsignedIntTy;
2342}
2343
2344/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
2345/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
2346QualType ASTContext::getPointerDiffType() const {
2347  return getFromTargetType(Target.getPtrDiffType(0));
2348}
2349
2350//===----------------------------------------------------------------------===//
2351//                              Type Operators
2352//===----------------------------------------------------------------------===//
2353
2354CanQualType ASTContext::getCanonicalParamType(QualType T) {
2355  // Push qualifiers into arrays, and then discard any remaining
2356  // qualifiers.
2357  T = getCanonicalType(T);
2358  const Type *Ty = T.getTypePtr();
2359
2360  QualType Result;
2361  if (isa<ArrayType>(Ty)) {
2362    Result = getArrayDecayedType(QualType(Ty,0));
2363  } else if (isa<FunctionType>(Ty)) {
2364    Result = getPointerType(QualType(Ty, 0));
2365  } else {
2366    Result = QualType(Ty, 0);
2367  }
2368
2369  return CanQualType::CreateUnsafe(Result);
2370}
2371
2372/// getCanonicalType - Return the canonical (structural) type corresponding to
2373/// the specified potentially non-canonical type.  The non-canonical version
2374/// of a type may have many "decorated" versions of types.  Decorators can
2375/// include typedefs, 'typeof' operators, etc. The returned type is guaranteed
2376/// to be free of any of these, allowing two canonical types to be compared
2377/// for exact equality with a simple pointer comparison.
2378CanQualType ASTContext::getCanonicalType(QualType T) {
2379  QualifierCollector Quals;
2380  const Type *Ptr = Quals.strip(T);
2381  QualType CanType = Ptr->getCanonicalTypeInternal();
2382
2383  // The canonical internal type will be the canonical type *except*
2384  // that we push type qualifiers down through array types.
2385
2386  // If there are no new qualifiers to push down, stop here.
2387  if (!Quals.hasQualifiers())
2388    return CanQualType::CreateUnsafe(CanType);
2389
2390  // If the type qualifiers are on an array type, get the canonical
2391  // type of the array with the qualifiers applied to the element
2392  // type.
2393  ArrayType *AT = dyn_cast<ArrayType>(CanType);
2394  if (!AT)
2395    return CanQualType::CreateUnsafe(getQualifiedType(CanType, Quals));
2396
2397  // Get the canonical version of the element with the extra qualifiers on it.
2398  // This can recursively sink qualifiers through multiple levels of arrays.
2399  QualType NewEltTy = getQualifiedType(AT->getElementType(), Quals);
2400  NewEltTy = getCanonicalType(NewEltTy);
2401
2402  if (ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
2403    return CanQualType::CreateUnsafe(
2404             getConstantArrayType(NewEltTy, CAT->getSize(),
2405                                  CAT->getSizeModifier(),
2406                                  CAT->getIndexTypeCVRQualifiers()));
2407  if (IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT))
2408    return CanQualType::CreateUnsafe(
2409             getIncompleteArrayType(NewEltTy, IAT->getSizeModifier(),
2410                                    IAT->getIndexTypeCVRQualifiers()));
2411
2412  if (DependentSizedArrayType *DSAT = dyn_cast<DependentSizedArrayType>(AT))
2413    return CanQualType::CreateUnsafe(
2414             getDependentSizedArrayType(NewEltTy,
2415                                        DSAT->getSizeExpr() ?
2416                                          DSAT->getSizeExpr()->Retain() : 0,
2417                                        DSAT->getSizeModifier(),
2418                                        DSAT->getIndexTypeCVRQualifiers(),
2419                        DSAT->getBracketsRange())->getCanonicalTypeInternal());
2420
2421  VariableArrayType *VAT = cast<VariableArrayType>(AT);
2422  return CanQualType::CreateUnsafe(getVariableArrayType(NewEltTy,
2423                                                        VAT->getSizeExpr() ?
2424                                              VAT->getSizeExpr()->Retain() : 0,
2425                                                        VAT->getSizeModifier(),
2426                                              VAT->getIndexTypeCVRQualifiers(),
2427                                                     VAT->getBracketsRange()));
2428}
2429
2430QualType ASTContext::getUnqualifiedArrayType(QualType T,
2431                                             Qualifiers &Quals) {
2432  Quals = T.getQualifiers();
2433  const ArrayType *AT = getAsArrayType(T);
2434  if (!AT) {
2435    return T.getUnqualifiedType();
2436  }
2437
2438  QualType Elt = AT->getElementType();
2439  QualType UnqualElt = getUnqualifiedArrayType(Elt, Quals);
2440  if (Elt == UnqualElt)
2441    return T;
2442
2443  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
2444    return getConstantArrayType(UnqualElt, CAT->getSize(),
2445                                CAT->getSizeModifier(), 0);
2446  }
2447
2448  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
2449    return getIncompleteArrayType(UnqualElt, IAT->getSizeModifier(), 0);
2450  }
2451
2452  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
2453    return getVariableArrayType(UnqualElt,
2454                                VAT->getSizeExpr() ?
2455                                VAT->getSizeExpr()->Retain() : 0,
2456                                VAT->getSizeModifier(),
2457                                VAT->getIndexTypeCVRQualifiers(),
2458                                VAT->getBracketsRange());
2459  }
2460
2461  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
2462  return getDependentSizedArrayType(UnqualElt, DSAT->getSizeExpr()->Retain(),
2463                                    DSAT->getSizeModifier(), 0,
2464                                    SourceRange());
2465}
2466
2467/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
2468/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
2469/// they point to and return true. If T1 and T2 aren't pointer types
2470/// or pointer-to-member types, or if they are not similar at this
2471/// level, returns false and leaves T1 and T2 unchanged. Top-level
2472/// qualifiers on T1 and T2 are ignored. This function will typically
2473/// be called in a loop that successively "unwraps" pointer and
2474/// pointer-to-member types to compare them at each level.
2475bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
2476  const PointerType *T1PtrType = T1->getAs<PointerType>(),
2477                    *T2PtrType = T2->getAs<PointerType>();
2478  if (T1PtrType && T2PtrType) {
2479    T1 = T1PtrType->getPointeeType();
2480    T2 = T2PtrType->getPointeeType();
2481    return true;
2482  }
2483
2484  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
2485                          *T2MPType = T2->getAs<MemberPointerType>();
2486  if (T1MPType && T2MPType &&
2487      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
2488                             QualType(T2MPType->getClass(), 0))) {
2489    T1 = T1MPType->getPointeeType();
2490    T2 = T2MPType->getPointeeType();
2491    return true;
2492  }
2493
2494  if (getLangOptions().ObjC1) {
2495    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
2496                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
2497    if (T1OPType && T2OPType) {
2498      T1 = T1OPType->getPointeeType();
2499      T2 = T2OPType->getPointeeType();
2500      return true;
2501    }
2502  }
2503
2504  // FIXME: Block pointers, too?
2505
2506  return false;
2507}
2508
2509DeclarationNameInfo ASTContext::getNameForTemplate(TemplateName Name,
2510                                                   SourceLocation NameLoc) {
2511  if (TemplateDecl *TD = Name.getAsTemplateDecl())
2512    // DNInfo work in progress: CHECKME: what about DNLoc?
2513    return DeclarationNameInfo(TD->getDeclName(), NameLoc);
2514
2515  if (DependentTemplateName *DTN = Name.getAsDependentTemplateName()) {
2516    DeclarationName DName;
2517    if (DTN->isIdentifier()) {
2518      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
2519      return DeclarationNameInfo(DName, NameLoc);
2520    } else {
2521      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
2522      // DNInfo work in progress: FIXME: source locations?
2523      DeclarationNameLoc DNLoc;
2524      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
2525      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
2526      return DeclarationNameInfo(DName, NameLoc, DNLoc);
2527    }
2528  }
2529
2530  OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
2531  assert(Storage);
2532  // DNInfo work in progress: CHECKME: what about DNLoc?
2533  return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
2534}
2535
2536TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) {
2537  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
2538    if (TemplateTemplateParmDecl *TTP
2539                              = dyn_cast<TemplateTemplateParmDecl>(Template))
2540      Template = getCanonicalTemplateTemplateParmDecl(TTP);
2541
2542    // The canonical template name is the canonical template declaration.
2543    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
2544  }
2545
2546  assert(!Name.getAsOverloadedTemplate());
2547
2548  DependentTemplateName *DTN = Name.getAsDependentTemplateName();
2549  assert(DTN && "Non-dependent template names must refer to template decls.");
2550  return DTN->CanonicalTemplateName;
2551}
2552
2553bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
2554  X = getCanonicalTemplateName(X);
2555  Y = getCanonicalTemplateName(Y);
2556  return X.getAsVoidPointer() == Y.getAsVoidPointer();
2557}
2558
2559TemplateArgument
2560ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) {
2561  switch (Arg.getKind()) {
2562    case TemplateArgument::Null:
2563      return Arg;
2564
2565    case TemplateArgument::Expression:
2566      return Arg;
2567
2568    case TemplateArgument::Declaration:
2569      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
2570
2571    case TemplateArgument::Template:
2572      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
2573
2574    case TemplateArgument::Integral:
2575      return TemplateArgument(*Arg.getAsIntegral(),
2576                              getCanonicalType(Arg.getIntegralType()));
2577
2578    case TemplateArgument::Type:
2579      return TemplateArgument(getCanonicalType(Arg.getAsType()));
2580
2581    case TemplateArgument::Pack: {
2582      // FIXME: Allocate in ASTContext
2583      TemplateArgument *CanonArgs = new TemplateArgument[Arg.pack_size()];
2584      unsigned Idx = 0;
2585      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
2586                                        AEnd = Arg.pack_end();
2587           A != AEnd; (void)++A, ++Idx)
2588        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
2589
2590      TemplateArgument Result;
2591      Result.setArgumentPack(CanonArgs, Arg.pack_size(), false);
2592      return Result;
2593    }
2594  }
2595
2596  // Silence GCC warning
2597  assert(false && "Unhandled template argument kind");
2598  return TemplateArgument();
2599}
2600
2601NestedNameSpecifier *
2602ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) {
2603  if (!NNS)
2604    return 0;
2605
2606  switch (NNS->getKind()) {
2607  case NestedNameSpecifier::Identifier:
2608    // Canonicalize the prefix but keep the identifier the same.
2609    return NestedNameSpecifier::Create(*this,
2610                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
2611                                       NNS->getAsIdentifier());
2612
2613  case NestedNameSpecifier::Namespace:
2614    // A namespace is canonical; build a nested-name-specifier with
2615    // this namespace and no prefix.
2616    return NestedNameSpecifier::Create(*this, 0, NNS->getAsNamespace());
2617
2618  case NestedNameSpecifier::TypeSpec:
2619  case NestedNameSpecifier::TypeSpecWithTemplate: {
2620    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
2621    return NestedNameSpecifier::Create(*this, 0,
2622                 NNS->getKind() == NestedNameSpecifier::TypeSpecWithTemplate,
2623                                       T.getTypePtr());
2624  }
2625
2626  case NestedNameSpecifier::Global:
2627    // The global specifier is canonical and unique.
2628    return NNS;
2629  }
2630
2631  // Required to silence a GCC warning
2632  return 0;
2633}
2634
2635
2636const ArrayType *ASTContext::getAsArrayType(QualType T) {
2637  // Handle the non-qualified case efficiently.
2638  if (!T.hasLocalQualifiers()) {
2639    // Handle the common positive case fast.
2640    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
2641      return AT;
2642  }
2643
2644  // Handle the common negative case fast.
2645  QualType CType = T->getCanonicalTypeInternal();
2646  if (!isa<ArrayType>(CType))
2647    return 0;
2648
2649  // Apply any qualifiers from the array type to the element type.  This
2650  // implements C99 6.7.3p8: "If the specification of an array type includes
2651  // any type qualifiers, the element type is so qualified, not the array type."
2652
2653  // If we get here, we either have type qualifiers on the type, or we have
2654  // sugar such as a typedef in the way.  If we have type qualifiers on the type
2655  // we must propagate them down into the element type.
2656
2657  QualifierCollector Qs;
2658  const Type *Ty = Qs.strip(T.getDesugaredType());
2659
2660  // If we have a simple case, just return now.
2661  const ArrayType *ATy = dyn_cast<ArrayType>(Ty);
2662  if (ATy == 0 || Qs.empty())
2663    return ATy;
2664
2665  // Otherwise, we have an array and we have qualifiers on it.  Push the
2666  // qualifiers into the array element type and return a new array type.
2667  // Get the canonical version of the element with the extra qualifiers on it.
2668  // This can recursively sink qualifiers through multiple levels of arrays.
2669  QualType NewEltTy = getQualifiedType(ATy->getElementType(), Qs);
2670
2671  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
2672    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
2673                                                CAT->getSizeModifier(),
2674                                           CAT->getIndexTypeCVRQualifiers()));
2675  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
2676    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
2677                                                  IAT->getSizeModifier(),
2678                                           IAT->getIndexTypeCVRQualifiers()));
2679
2680  if (const DependentSizedArrayType *DSAT
2681        = dyn_cast<DependentSizedArrayType>(ATy))
2682    return cast<ArrayType>(
2683                     getDependentSizedArrayType(NewEltTy,
2684                                                DSAT->getSizeExpr() ?
2685                                              DSAT->getSizeExpr()->Retain() : 0,
2686                                                DSAT->getSizeModifier(),
2687                                              DSAT->getIndexTypeCVRQualifiers(),
2688                                                DSAT->getBracketsRange()));
2689
2690  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
2691  return cast<ArrayType>(getVariableArrayType(NewEltTy,
2692                                              VAT->getSizeExpr() ?
2693                                              VAT->getSizeExpr()->Retain() : 0,
2694                                              VAT->getSizeModifier(),
2695                                              VAT->getIndexTypeCVRQualifiers(),
2696                                              VAT->getBracketsRange()));
2697}
2698
2699
2700/// getArrayDecayedType - Return the properly qualified result of decaying the
2701/// specified array type to a pointer.  This operation is non-trivial when
2702/// handling typedefs etc.  The canonical type of "T" must be an array type,
2703/// this returns a pointer to a properly qualified element of the array.
2704///
2705/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
2706QualType ASTContext::getArrayDecayedType(QualType Ty) {
2707  // Get the element type with 'getAsArrayType' so that we don't lose any
2708  // typedefs in the element type of the array.  This also handles propagation
2709  // of type qualifiers from the array type into the element type if present
2710  // (C99 6.7.3p8).
2711  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
2712  assert(PrettyArrayType && "Not an array type!");
2713
2714  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
2715
2716  // int x[restrict 4] ->  int *restrict
2717  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
2718}
2719
2720QualType ASTContext::getBaseElementType(QualType QT) {
2721  QualifierCollector Qs;
2722  while (const ArrayType *AT = getAsArrayType(QualType(Qs.strip(QT), 0)))
2723    QT = AT->getElementType();
2724  return Qs.apply(QT);
2725}
2726
2727QualType ASTContext::getBaseElementType(const ArrayType *AT) {
2728  QualType ElemTy = AT->getElementType();
2729
2730  if (const ArrayType *AT = getAsArrayType(ElemTy))
2731    return getBaseElementType(AT);
2732
2733  return ElemTy;
2734}
2735
2736/// getConstantArrayElementCount - Returns number of constant array elements.
2737uint64_t
2738ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
2739  uint64_t ElementCount = 1;
2740  do {
2741    ElementCount *= CA->getSize().getZExtValue();
2742    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
2743  } while (CA);
2744  return ElementCount;
2745}
2746
2747/// getFloatingRank - Return a relative rank for floating point types.
2748/// This routine will assert if passed a built-in type that isn't a float.
2749static FloatingRank getFloatingRank(QualType T) {
2750  if (const ComplexType *CT = T->getAs<ComplexType>())
2751    return getFloatingRank(CT->getElementType());
2752
2753  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
2754  switch (T->getAs<BuiltinType>()->getKind()) {
2755  default: assert(0 && "getFloatingRank(): not a floating type");
2756  case BuiltinType::Float:      return FloatRank;
2757  case BuiltinType::Double:     return DoubleRank;
2758  case BuiltinType::LongDouble: return LongDoubleRank;
2759  }
2760}
2761
2762/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
2763/// point or a complex type (based on typeDomain/typeSize).
2764/// 'typeDomain' is a real floating point or complex type.
2765/// 'typeSize' is a real floating point or complex type.
2766QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
2767                                                       QualType Domain) const {
2768  FloatingRank EltRank = getFloatingRank(Size);
2769  if (Domain->isComplexType()) {
2770    switch (EltRank) {
2771    default: assert(0 && "getFloatingRank(): illegal value for rank");
2772    case FloatRank:      return FloatComplexTy;
2773    case DoubleRank:     return DoubleComplexTy;
2774    case LongDoubleRank: return LongDoubleComplexTy;
2775    }
2776  }
2777
2778  assert(Domain->isRealFloatingType() && "Unknown domain!");
2779  switch (EltRank) {
2780  default: assert(0 && "getFloatingRank(): illegal value for rank");
2781  case FloatRank:      return FloatTy;
2782  case DoubleRank:     return DoubleTy;
2783  case LongDoubleRank: return LongDoubleTy;
2784  }
2785}
2786
2787/// getFloatingTypeOrder - Compare the rank of the two specified floating
2788/// point types, ignoring the domain of the type (i.e. 'double' ==
2789/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2790/// LHS < RHS, return -1.
2791int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) {
2792  FloatingRank LHSR = getFloatingRank(LHS);
2793  FloatingRank RHSR = getFloatingRank(RHS);
2794
2795  if (LHSR == RHSR)
2796    return 0;
2797  if (LHSR > RHSR)
2798    return 1;
2799  return -1;
2800}
2801
2802/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
2803/// routine will assert if passed a built-in type that isn't an integer or enum,
2804/// or if it is not canonicalized.
2805unsigned ASTContext::getIntegerRank(Type *T) {
2806  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
2807  if (EnumType* ET = dyn_cast<EnumType>(T))
2808    T = ET->getDecl()->getPromotionType().getTypePtr();
2809
2810  if (T->isSpecificBuiltinType(BuiltinType::WChar))
2811    T = getFromTargetType(Target.getWCharType()).getTypePtr();
2812
2813  if (T->isSpecificBuiltinType(BuiltinType::Char16))
2814    T = getFromTargetType(Target.getChar16Type()).getTypePtr();
2815
2816  if (T->isSpecificBuiltinType(BuiltinType::Char32))
2817    T = getFromTargetType(Target.getChar32Type()).getTypePtr();
2818
2819  switch (cast<BuiltinType>(T)->getKind()) {
2820  default: assert(0 && "getIntegerRank(): not a built-in integer");
2821  case BuiltinType::Bool:
2822    return 1 + (getIntWidth(BoolTy) << 3);
2823  case BuiltinType::Char_S:
2824  case BuiltinType::Char_U:
2825  case BuiltinType::SChar:
2826  case BuiltinType::UChar:
2827    return 2 + (getIntWidth(CharTy) << 3);
2828  case BuiltinType::Short:
2829  case BuiltinType::UShort:
2830    return 3 + (getIntWidth(ShortTy) << 3);
2831  case BuiltinType::Int:
2832  case BuiltinType::UInt:
2833    return 4 + (getIntWidth(IntTy) << 3);
2834  case BuiltinType::Long:
2835  case BuiltinType::ULong:
2836    return 5 + (getIntWidth(LongTy) << 3);
2837  case BuiltinType::LongLong:
2838  case BuiltinType::ULongLong:
2839    return 6 + (getIntWidth(LongLongTy) << 3);
2840  case BuiltinType::Int128:
2841  case BuiltinType::UInt128:
2842    return 7 + (getIntWidth(Int128Ty) << 3);
2843  }
2844}
2845
2846/// \brief Whether this is a promotable bitfield reference according
2847/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
2848///
2849/// \returns the type this bit-field will promote to, or NULL if no
2850/// promotion occurs.
2851QualType ASTContext::isPromotableBitField(Expr *E) {
2852  if (E->isTypeDependent() || E->isValueDependent())
2853    return QualType();
2854
2855  FieldDecl *Field = E->getBitField();
2856  if (!Field)
2857    return QualType();
2858
2859  QualType FT = Field->getType();
2860
2861  llvm::APSInt BitWidthAP = Field->getBitWidth()->EvaluateAsInt(*this);
2862  uint64_t BitWidth = BitWidthAP.getZExtValue();
2863  uint64_t IntSize = getTypeSize(IntTy);
2864  // GCC extension compatibility: if the bit-field size is less than or equal
2865  // to the size of int, it gets promoted no matter what its type is.
2866  // For instance, unsigned long bf : 4 gets promoted to signed int.
2867  if (BitWidth < IntSize)
2868    return IntTy;
2869
2870  if (BitWidth == IntSize)
2871    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
2872
2873  // Types bigger than int are not subject to promotions, and therefore act
2874  // like the base type.
2875  // FIXME: This doesn't quite match what gcc does, but what gcc does here
2876  // is ridiculous.
2877  return QualType();
2878}
2879
2880/// getPromotedIntegerType - Returns the type that Promotable will
2881/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
2882/// integer type.
2883QualType ASTContext::getPromotedIntegerType(QualType Promotable) {
2884  assert(!Promotable.isNull());
2885  assert(Promotable->isPromotableIntegerType());
2886  if (const EnumType *ET = Promotable->getAs<EnumType>())
2887    return ET->getDecl()->getPromotionType();
2888  if (Promotable->isSignedIntegerType())
2889    return IntTy;
2890  uint64_t PromotableSize = getTypeSize(Promotable);
2891  uint64_t IntSize = getTypeSize(IntTy);
2892  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
2893  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
2894}
2895
2896/// getIntegerTypeOrder - Returns the highest ranked integer type:
2897/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2898/// LHS < RHS, return -1.
2899int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) {
2900  Type *LHSC = getCanonicalType(LHS).getTypePtr();
2901  Type *RHSC = getCanonicalType(RHS).getTypePtr();
2902  if (LHSC == RHSC) return 0;
2903
2904  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
2905  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
2906
2907  unsigned LHSRank = getIntegerRank(LHSC);
2908  unsigned RHSRank = getIntegerRank(RHSC);
2909
2910  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
2911    if (LHSRank == RHSRank) return 0;
2912    return LHSRank > RHSRank ? 1 : -1;
2913  }
2914
2915  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
2916  if (LHSUnsigned) {
2917    // If the unsigned [LHS] type is larger, return it.
2918    if (LHSRank >= RHSRank)
2919      return 1;
2920
2921    // If the signed type can represent all values of the unsigned type, it
2922    // wins.  Because we are dealing with 2's complement and types that are
2923    // powers of two larger than each other, this is always safe.
2924    return -1;
2925  }
2926
2927  // If the unsigned [RHS] type is larger, return it.
2928  if (RHSRank >= LHSRank)
2929    return -1;
2930
2931  // If the signed type can represent all values of the unsigned type, it
2932  // wins.  Because we are dealing with 2's complement and types that are
2933  // powers of two larger than each other, this is always safe.
2934  return 1;
2935}
2936
2937static RecordDecl *
2938CreateRecordDecl(ASTContext &Ctx, RecordDecl::TagKind TK, DeclContext *DC,
2939                 SourceLocation L, IdentifierInfo *Id) {
2940  if (Ctx.getLangOptions().CPlusPlus)
2941    return CXXRecordDecl::Create(Ctx, TK, DC, L, Id);
2942  else
2943    return RecordDecl::Create(Ctx, TK, DC, L, Id);
2944}
2945
2946// getCFConstantStringType - Return the type used for constant CFStrings.
2947QualType ASTContext::getCFConstantStringType() {
2948  if (!CFConstantStringTypeDecl) {
2949    CFConstantStringTypeDecl =
2950      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
2951                       &Idents.get("NSConstantString"));
2952    CFConstantStringTypeDecl->startDefinition();
2953
2954    QualType FieldTypes[4];
2955
2956    // const int *isa;
2957    FieldTypes[0] = getPointerType(IntTy.withConst());
2958    // int flags;
2959    FieldTypes[1] = IntTy;
2960    // const char *str;
2961    FieldTypes[2] = getPointerType(CharTy.withConst());
2962    // long length;
2963    FieldTypes[3] = LongTy;
2964
2965    // Create fields
2966    for (unsigned i = 0; i < 4; ++i) {
2967      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
2968                                           SourceLocation(), 0,
2969                                           FieldTypes[i], /*TInfo=*/0,
2970                                           /*BitWidth=*/0,
2971                                           /*Mutable=*/false);
2972      Field->setAccess(AS_public);
2973      CFConstantStringTypeDecl->addDecl(Field);
2974    }
2975
2976    CFConstantStringTypeDecl->completeDefinition();
2977  }
2978
2979  return getTagDeclType(CFConstantStringTypeDecl);
2980}
2981
2982void ASTContext::setCFConstantStringType(QualType T) {
2983  const RecordType *Rec = T->getAs<RecordType>();
2984  assert(Rec && "Invalid CFConstantStringType");
2985  CFConstantStringTypeDecl = Rec->getDecl();
2986}
2987
2988// getNSConstantStringType - Return the type used for constant NSStrings.
2989QualType ASTContext::getNSConstantStringType() {
2990  if (!NSConstantStringTypeDecl) {
2991    NSConstantStringTypeDecl =
2992    CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
2993                     &Idents.get("__builtin_NSString"));
2994    NSConstantStringTypeDecl->startDefinition();
2995
2996    QualType FieldTypes[3];
2997
2998    // const int *isa;
2999    FieldTypes[0] = getPointerType(IntTy.withConst());
3000    // const char *str;
3001    FieldTypes[1] = getPointerType(CharTy.withConst());
3002    // unsigned int length;
3003    FieldTypes[2] = UnsignedIntTy;
3004
3005    // Create fields
3006    for (unsigned i = 0; i < 3; ++i) {
3007      FieldDecl *Field = FieldDecl::Create(*this, NSConstantStringTypeDecl,
3008                                           SourceLocation(), 0,
3009                                           FieldTypes[i], /*TInfo=*/0,
3010                                           /*BitWidth=*/0,
3011                                           /*Mutable=*/false);
3012      Field->setAccess(AS_public);
3013      NSConstantStringTypeDecl->addDecl(Field);
3014    }
3015
3016    NSConstantStringTypeDecl->completeDefinition();
3017  }
3018
3019  return getTagDeclType(NSConstantStringTypeDecl);
3020}
3021
3022void ASTContext::setNSConstantStringType(QualType T) {
3023  const RecordType *Rec = T->getAs<RecordType>();
3024  assert(Rec && "Invalid NSConstantStringType");
3025  NSConstantStringTypeDecl = Rec->getDecl();
3026}
3027
3028QualType ASTContext::getObjCFastEnumerationStateType() {
3029  if (!ObjCFastEnumerationStateTypeDecl) {
3030    ObjCFastEnumerationStateTypeDecl =
3031      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3032                       &Idents.get("__objcFastEnumerationState"));
3033    ObjCFastEnumerationStateTypeDecl->startDefinition();
3034
3035    QualType FieldTypes[] = {
3036      UnsignedLongTy,
3037      getPointerType(ObjCIdTypedefType),
3038      getPointerType(UnsignedLongTy),
3039      getConstantArrayType(UnsignedLongTy,
3040                           llvm::APInt(32, 5), ArrayType::Normal, 0)
3041    };
3042
3043    for (size_t i = 0; i < 4; ++i) {
3044      FieldDecl *Field = FieldDecl::Create(*this,
3045                                           ObjCFastEnumerationStateTypeDecl,
3046                                           SourceLocation(), 0,
3047                                           FieldTypes[i], /*TInfo=*/0,
3048                                           /*BitWidth=*/0,
3049                                           /*Mutable=*/false);
3050      Field->setAccess(AS_public);
3051      ObjCFastEnumerationStateTypeDecl->addDecl(Field);
3052    }
3053    if (getLangOptions().CPlusPlus)
3054      if (CXXRecordDecl *CXXRD =
3055            dyn_cast<CXXRecordDecl>(ObjCFastEnumerationStateTypeDecl))
3056        CXXRD->setEmpty(false);
3057
3058    ObjCFastEnumerationStateTypeDecl->completeDefinition();
3059  }
3060
3061  return getTagDeclType(ObjCFastEnumerationStateTypeDecl);
3062}
3063
3064QualType ASTContext::getBlockDescriptorType() {
3065  if (BlockDescriptorType)
3066    return getTagDeclType(BlockDescriptorType);
3067
3068  RecordDecl *T;
3069  // FIXME: Needs the FlagAppleBlock bit.
3070  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3071                       &Idents.get("__block_descriptor"));
3072  T->startDefinition();
3073
3074  QualType FieldTypes[] = {
3075    UnsignedLongTy,
3076    UnsignedLongTy,
3077  };
3078
3079  const char *FieldNames[] = {
3080    "reserved",
3081    "Size"
3082  };
3083
3084  for (size_t i = 0; i < 2; ++i) {
3085    FieldDecl *Field = FieldDecl::Create(*this,
3086                                         T,
3087                                         SourceLocation(),
3088                                         &Idents.get(FieldNames[i]),
3089                                         FieldTypes[i], /*TInfo=*/0,
3090                                         /*BitWidth=*/0,
3091                                         /*Mutable=*/false);
3092    Field->setAccess(AS_public);
3093    T->addDecl(Field);
3094  }
3095
3096  T->completeDefinition();
3097
3098  BlockDescriptorType = T;
3099
3100  return getTagDeclType(BlockDescriptorType);
3101}
3102
3103void ASTContext::setBlockDescriptorType(QualType T) {
3104  const RecordType *Rec = T->getAs<RecordType>();
3105  assert(Rec && "Invalid BlockDescriptorType");
3106  BlockDescriptorType = Rec->getDecl();
3107}
3108
3109QualType ASTContext::getBlockDescriptorExtendedType() {
3110  if (BlockDescriptorExtendedType)
3111    return getTagDeclType(BlockDescriptorExtendedType);
3112
3113  RecordDecl *T;
3114  // FIXME: Needs the FlagAppleBlock bit.
3115  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3116                       &Idents.get("__block_descriptor_withcopydispose"));
3117  T->startDefinition();
3118
3119  QualType FieldTypes[] = {
3120    UnsignedLongTy,
3121    UnsignedLongTy,
3122    getPointerType(VoidPtrTy),
3123    getPointerType(VoidPtrTy)
3124  };
3125
3126  const char *FieldNames[] = {
3127    "reserved",
3128    "Size",
3129    "CopyFuncPtr",
3130    "DestroyFuncPtr"
3131  };
3132
3133  for (size_t i = 0; i < 4; ++i) {
3134    FieldDecl *Field = FieldDecl::Create(*this,
3135                                         T,
3136                                         SourceLocation(),
3137                                         &Idents.get(FieldNames[i]),
3138                                         FieldTypes[i], /*TInfo=*/0,
3139                                         /*BitWidth=*/0,
3140                                         /*Mutable=*/false);
3141    Field->setAccess(AS_public);
3142    T->addDecl(Field);
3143  }
3144
3145  T->completeDefinition();
3146
3147  BlockDescriptorExtendedType = T;
3148
3149  return getTagDeclType(BlockDescriptorExtendedType);
3150}
3151
3152void ASTContext::setBlockDescriptorExtendedType(QualType T) {
3153  const RecordType *Rec = T->getAs<RecordType>();
3154  assert(Rec && "Invalid BlockDescriptorType");
3155  BlockDescriptorExtendedType = Rec->getDecl();
3156}
3157
3158bool ASTContext::BlockRequiresCopying(QualType Ty) {
3159  if (Ty->isBlockPointerType())
3160    return true;
3161  if (isObjCNSObjectType(Ty))
3162    return true;
3163  if (Ty->isObjCObjectPointerType())
3164    return true;
3165  return false;
3166}
3167
3168QualType ASTContext::BuildByRefType(llvm::StringRef DeclName, QualType Ty) {
3169  //  type = struct __Block_byref_1_X {
3170  //    void *__isa;
3171  //    struct __Block_byref_1_X *__forwarding;
3172  //    unsigned int __flags;
3173  //    unsigned int __size;
3174  //    void *__copy_helper;            // as needed
3175  //    void *__destroy_help            // as needed
3176  //    int X;
3177  //  } *
3178
3179  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3180
3181  // FIXME: Move up
3182  llvm::SmallString<36> Name;
3183  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3184                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3185  RecordDecl *T;
3186  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3187                       &Idents.get(Name.str()));
3188  T->startDefinition();
3189  QualType Int32Ty = IntTy;
3190  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3191  QualType FieldTypes[] = {
3192    getPointerType(VoidPtrTy),
3193    getPointerType(getTagDeclType(T)),
3194    Int32Ty,
3195    Int32Ty,
3196    getPointerType(VoidPtrTy),
3197    getPointerType(VoidPtrTy),
3198    Ty
3199  };
3200
3201  llvm::StringRef FieldNames[] = {
3202    "__isa",
3203    "__forwarding",
3204    "__flags",
3205    "__size",
3206    "__copy_helper",
3207    "__destroy_helper",
3208    DeclName,
3209  };
3210
3211  for (size_t i = 0; i < 7; ++i) {
3212    if (!HasCopyAndDispose && i >=4 && i <= 5)
3213      continue;
3214    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3215                                         &Idents.get(FieldNames[i]),
3216                                         FieldTypes[i], /*TInfo=*/0,
3217                                         /*BitWidth=*/0, /*Mutable=*/false);
3218    Field->setAccess(AS_public);
3219    T->addDecl(Field);
3220  }
3221
3222  T->completeDefinition();
3223
3224  return getPointerType(getTagDeclType(T));
3225}
3226
3227
3228QualType ASTContext::getBlockParmType(
3229  bool BlockHasCopyDispose,
3230  llvm::SmallVectorImpl<const Expr *> &Layout) {
3231
3232  // FIXME: Move up
3233  llvm::SmallString<36> Name;
3234  llvm::raw_svector_ostream(Name) << "__block_literal_"
3235                                  << ++UniqueBlockParmTypeID;
3236  RecordDecl *T;
3237  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3238                       &Idents.get(Name.str()));
3239  T->startDefinition();
3240  QualType FieldTypes[] = {
3241    getPointerType(VoidPtrTy),
3242    IntTy,
3243    IntTy,
3244    getPointerType(VoidPtrTy),
3245    (BlockHasCopyDispose ?
3246     getPointerType(getBlockDescriptorExtendedType()) :
3247     getPointerType(getBlockDescriptorType()))
3248  };
3249
3250  const char *FieldNames[] = {
3251    "__isa",
3252    "__flags",
3253    "__reserved",
3254    "__FuncPtr",
3255    "__descriptor"
3256  };
3257
3258  for (size_t i = 0; i < 5; ++i) {
3259    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3260                                         &Idents.get(FieldNames[i]),
3261                                         FieldTypes[i], /*TInfo=*/0,
3262                                         /*BitWidth=*/0, /*Mutable=*/false);
3263    Field->setAccess(AS_public);
3264    T->addDecl(Field);
3265  }
3266
3267  for (unsigned i = 0; i < Layout.size(); ++i) {
3268    const Expr *E = Layout[i];
3269
3270    QualType FieldType = E->getType();
3271    IdentifierInfo *FieldName = 0;
3272    if (isa<CXXThisExpr>(E)) {
3273      FieldName = &Idents.get("this");
3274    } else if (const BlockDeclRefExpr *BDRE = dyn_cast<BlockDeclRefExpr>(E)) {
3275      const ValueDecl *D = BDRE->getDecl();
3276      FieldName = D->getIdentifier();
3277      if (BDRE->isByRef())
3278        FieldType = BuildByRefType(D->getName(), FieldType);
3279    } else {
3280      // Padding.
3281      assert(isa<ConstantArrayType>(FieldType) &&
3282             isa<DeclRefExpr>(E) &&
3283             !cast<DeclRefExpr>(E)->getDecl()->getDeclName() &&
3284             "doesn't match characteristics of padding decl");
3285    }
3286
3287    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3288                                         FieldName, FieldType, /*TInfo=*/0,
3289                                         /*BitWidth=*/0, /*Mutable=*/false);
3290    Field->setAccess(AS_public);
3291    T->addDecl(Field);
3292  }
3293
3294  T->completeDefinition();
3295
3296  return getPointerType(getTagDeclType(T));
3297}
3298
3299void ASTContext::setObjCFastEnumerationStateType(QualType T) {
3300  const RecordType *Rec = T->getAs<RecordType>();
3301  assert(Rec && "Invalid ObjCFAstEnumerationStateType");
3302  ObjCFastEnumerationStateTypeDecl = Rec->getDecl();
3303}
3304
3305// This returns true if a type has been typedefed to BOOL:
3306// typedef <type> BOOL;
3307static bool isTypeTypedefedAsBOOL(QualType T) {
3308  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3309    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3310      return II->isStr("BOOL");
3311
3312  return false;
3313}
3314
3315/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3316/// purpose.
3317CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) {
3318  CharUnits sz = getTypeSizeInChars(type);
3319
3320  // Make all integer and enum types at least as large as an int
3321  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3322    sz = std::max(sz, getTypeSizeInChars(IntTy));
3323  // Treat arrays as pointers, since that's how they're passed in.
3324  else if (type->isArrayType())
3325    sz = getTypeSizeInChars(VoidPtrTy);
3326  return sz;
3327}
3328
3329static inline
3330std::string charUnitsToString(const CharUnits &CU) {
3331  return llvm::itostr(CU.getQuantity());
3332}
3333
3334/// getObjCEncodingForBlockDecl - Return the encoded type for this block
3335/// declaration.
3336void ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr,
3337                                             std::string& S) {
3338  const BlockDecl *Decl = Expr->getBlockDecl();
3339  QualType BlockTy =
3340      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3341  // Encode result type.
3342  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3343  // Compute size of all parameters.
3344  // Start with computing size of a pointer in number of bytes.
3345  // FIXME: There might(should) be a better way of doing this computation!
3346  SourceLocation Loc;
3347  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3348  CharUnits ParmOffset = PtrSize;
3349  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3350       E = Decl->param_end(); PI != E; ++PI) {
3351    QualType PType = (*PI)->getType();
3352    CharUnits sz = getObjCEncodingTypeSize(PType);
3353    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3354    ParmOffset += sz;
3355  }
3356  // Size of the argument frame
3357  S += charUnitsToString(ParmOffset);
3358  // Block pointer and offset.
3359  S += "@?0";
3360  ParmOffset = PtrSize;
3361
3362  // Argument types.
3363  ParmOffset = PtrSize;
3364  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3365       Decl->param_end(); PI != E; ++PI) {
3366    ParmVarDecl *PVDecl = *PI;
3367    QualType PType = PVDecl->getOriginalType();
3368    if (const ArrayType *AT =
3369          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3370      // Use array's original type only if it has known number of
3371      // elements.
3372      if (!isa<ConstantArrayType>(AT))
3373        PType = PVDecl->getType();
3374    } else if (PType->isFunctionType())
3375      PType = PVDecl->getType();
3376    getObjCEncodingForType(PType, S);
3377    S += charUnitsToString(ParmOffset);
3378    ParmOffset += getObjCEncodingTypeSize(PType);
3379  }
3380}
3381
3382/// getObjCEncodingForMethodDecl - Return the encoded type for this method
3383/// declaration.
3384void ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
3385                                              std::string& S) {
3386  // FIXME: This is not very efficient.
3387  // Encode type qualifer, 'in', 'inout', etc. for the return type.
3388  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
3389  // Encode result type.
3390  getObjCEncodingForType(Decl->getResultType(), S);
3391  // Compute size of all parameters.
3392  // Start with computing size of a pointer in number of bytes.
3393  // FIXME: There might(should) be a better way of doing this computation!
3394  SourceLocation Loc;
3395  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3396  // The first two arguments (self and _cmd) are pointers; account for
3397  // their size.
3398  CharUnits ParmOffset = 2 * PtrSize;
3399  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3400       E = Decl->sel_param_end(); PI != E; ++PI) {
3401    QualType PType = (*PI)->getType();
3402    CharUnits sz = getObjCEncodingTypeSize(PType);
3403    assert (sz.isPositive() &&
3404        "getObjCEncodingForMethodDecl - Incomplete param type");
3405    ParmOffset += sz;
3406  }
3407  S += charUnitsToString(ParmOffset);
3408  S += "@0:";
3409  S += charUnitsToString(PtrSize);
3410
3411  // Argument types.
3412  ParmOffset = 2 * PtrSize;
3413  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3414       E = Decl->sel_param_end(); PI != E; ++PI) {
3415    ParmVarDecl *PVDecl = *PI;
3416    QualType PType = PVDecl->getOriginalType();
3417    if (const ArrayType *AT =
3418          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3419      // Use array's original type only if it has known number of
3420      // elements.
3421      if (!isa<ConstantArrayType>(AT))
3422        PType = PVDecl->getType();
3423    } else if (PType->isFunctionType())
3424      PType = PVDecl->getType();
3425    // Process argument qualifiers for user supplied arguments; such as,
3426    // 'in', 'inout', etc.
3427    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
3428    getObjCEncodingForType(PType, S);
3429    S += charUnitsToString(ParmOffset);
3430    ParmOffset += getObjCEncodingTypeSize(PType);
3431  }
3432}
3433
3434/// getObjCEncodingForPropertyDecl - Return the encoded type for this
3435/// property declaration. If non-NULL, Container must be either an
3436/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
3437/// NULL when getting encodings for protocol properties.
3438/// Property attributes are stored as a comma-delimited C string. The simple
3439/// attributes readonly and bycopy are encoded as single characters. The
3440/// parametrized attributes, getter=name, setter=name, and ivar=name, are
3441/// encoded as single characters, followed by an identifier. Property types
3442/// are also encoded as a parametrized attribute. The characters used to encode
3443/// these attributes are defined by the following enumeration:
3444/// @code
3445/// enum PropertyAttributes {
3446/// kPropertyReadOnly = 'R',   // property is read-only.
3447/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
3448/// kPropertyByref = '&',  // property is a reference to the value last assigned
3449/// kPropertyDynamic = 'D',    // property is dynamic
3450/// kPropertyGetter = 'G',     // followed by getter selector name
3451/// kPropertySetter = 'S',     // followed by setter selector name
3452/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
3453/// kPropertyType = 't'              // followed by old-style type encoding.
3454/// kPropertyWeak = 'W'              // 'weak' property
3455/// kPropertyStrong = 'P'            // property GC'able
3456/// kPropertyNonAtomic = 'N'         // property non-atomic
3457/// };
3458/// @endcode
3459void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
3460                                                const Decl *Container,
3461                                                std::string& S) {
3462  // Collect information from the property implementation decl(s).
3463  bool Dynamic = false;
3464  ObjCPropertyImplDecl *SynthesizePID = 0;
3465
3466  // FIXME: Duplicated code due to poor abstraction.
3467  if (Container) {
3468    if (const ObjCCategoryImplDecl *CID =
3469        dyn_cast<ObjCCategoryImplDecl>(Container)) {
3470      for (ObjCCategoryImplDecl::propimpl_iterator
3471             i = CID->propimpl_begin(), e = CID->propimpl_end();
3472           i != e; ++i) {
3473        ObjCPropertyImplDecl *PID = *i;
3474        if (PID->getPropertyDecl() == PD) {
3475          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3476            Dynamic = true;
3477          } else {
3478            SynthesizePID = PID;
3479          }
3480        }
3481      }
3482    } else {
3483      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
3484      for (ObjCCategoryImplDecl::propimpl_iterator
3485             i = OID->propimpl_begin(), e = OID->propimpl_end();
3486           i != e; ++i) {
3487        ObjCPropertyImplDecl *PID = *i;
3488        if (PID->getPropertyDecl() == PD) {
3489          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3490            Dynamic = true;
3491          } else {
3492            SynthesizePID = PID;
3493          }
3494        }
3495      }
3496    }
3497  }
3498
3499  // FIXME: This is not very efficient.
3500  S = "T";
3501
3502  // Encode result type.
3503  // GCC has some special rules regarding encoding of properties which
3504  // closely resembles encoding of ivars.
3505  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
3506                             true /* outermost type */,
3507                             true /* encoding for property */);
3508
3509  if (PD->isReadOnly()) {
3510    S += ",R";
3511  } else {
3512    switch (PD->getSetterKind()) {
3513    case ObjCPropertyDecl::Assign: break;
3514    case ObjCPropertyDecl::Copy:   S += ",C"; break;
3515    case ObjCPropertyDecl::Retain: S += ",&"; break;
3516    }
3517  }
3518
3519  // It really isn't clear at all what this means, since properties
3520  // are "dynamic by default".
3521  if (Dynamic)
3522    S += ",D";
3523
3524  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
3525    S += ",N";
3526
3527  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
3528    S += ",G";
3529    S += PD->getGetterName().getAsString();
3530  }
3531
3532  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
3533    S += ",S";
3534    S += PD->getSetterName().getAsString();
3535  }
3536
3537  if (SynthesizePID) {
3538    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
3539    S += ",V";
3540    S += OID->getNameAsString();
3541  }
3542
3543  // FIXME: OBJCGC: weak & strong
3544}
3545
3546/// getLegacyIntegralTypeEncoding -
3547/// Another legacy compatibility encoding: 32-bit longs are encoded as
3548/// 'l' or 'L' , but not always.  For typedefs, we need to use
3549/// 'i' or 'I' instead if encoding a struct field, or a pointer!
3550///
3551void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
3552  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
3553    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
3554      if (BT->getKind() == BuiltinType::ULong &&
3555          ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3556        PointeeTy = UnsignedIntTy;
3557      else
3558        if (BT->getKind() == BuiltinType::Long &&
3559            ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3560          PointeeTy = IntTy;
3561    }
3562  }
3563}
3564
3565void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
3566                                        const FieldDecl *Field) {
3567  // We follow the behavior of gcc, expanding structures which are
3568  // directly pointed to, and expanding embedded structures. Note that
3569  // these rules are sufficient to prevent recursive encoding of the
3570  // same type.
3571  getObjCEncodingForTypeImpl(T, S, true, true, Field,
3572                             true /* outermost type */);
3573}
3574
3575static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
3576    switch (T->getAs<BuiltinType>()->getKind()) {
3577    default: assert(0 && "Unhandled builtin type kind");
3578    case BuiltinType::Void:       return 'v';
3579    case BuiltinType::Bool:       return 'B';
3580    case BuiltinType::Char_U:
3581    case BuiltinType::UChar:      return 'C';
3582    case BuiltinType::UShort:     return 'S';
3583    case BuiltinType::UInt:       return 'I';
3584    case BuiltinType::ULong:
3585        return
3586          (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'L' : 'Q';
3587    case BuiltinType::UInt128:    return 'T';
3588    case BuiltinType::ULongLong:  return 'Q';
3589    case BuiltinType::Char_S:
3590    case BuiltinType::SChar:      return 'c';
3591    case BuiltinType::Short:      return 's';
3592    case BuiltinType::WChar:
3593    case BuiltinType::Int:        return 'i';
3594    case BuiltinType::Long:
3595      return
3596        (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'l' : 'q';
3597    case BuiltinType::LongLong:   return 'q';
3598    case BuiltinType::Int128:     return 't';
3599    case BuiltinType::Float:      return 'f';
3600    case BuiltinType::Double:     return 'd';
3601    case BuiltinType::LongDouble: return 'd';
3602    }
3603}
3604
3605static void EncodeBitField(const ASTContext *Context, std::string& S,
3606                           QualType T, const FieldDecl *FD) {
3607  const Expr *E = FD->getBitWidth();
3608  assert(E && "bitfield width not there - getObjCEncodingForTypeImpl");
3609  ASTContext *Ctx = const_cast<ASTContext*>(Context);
3610  S += 'b';
3611  // The NeXT runtime encodes bit fields as b followed by the number of bits.
3612  // The GNU runtime requires more information; bitfields are encoded as b,
3613  // then the offset (in bits) of the first element, then the type of the
3614  // bitfield, then the size in bits.  For example, in this structure:
3615  //
3616  // struct
3617  // {
3618  //    int integer;
3619  //    int flags:2;
3620  // };
3621  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
3622  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
3623  // information is not especially sensible, but we're stuck with it for
3624  // compatibility with GCC, although providing it breaks anything that
3625  // actually uses runtime introspection and wants to work on both runtimes...
3626  if (!Ctx->getLangOptions().NeXTRuntime) {
3627    const RecordDecl *RD = FD->getParent();
3628    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
3629    // FIXME: This same linear search is also used in ExprConstant - it might
3630    // be better if the FieldDecl stored its offset.  We'd be increasing the
3631    // size of the object slightly, but saving some time every time it is used.
3632    unsigned i = 0;
3633    for (RecordDecl::field_iterator Field = RD->field_begin(),
3634                                 FieldEnd = RD->field_end();
3635         Field != FieldEnd; (void)++Field, ++i) {
3636      if (*Field == FD)
3637        break;
3638    }
3639    S += llvm::utostr(RL.getFieldOffset(i));
3640    S += ObjCEncodingForPrimitiveKind(Context, T);
3641  }
3642  unsigned N = E->EvaluateAsInt(*Ctx).getZExtValue();
3643  S += llvm::utostr(N);
3644}
3645
3646// FIXME: Use SmallString for accumulating string.
3647void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
3648                                            bool ExpandPointedToStructures,
3649                                            bool ExpandStructures,
3650                                            const FieldDecl *FD,
3651                                            bool OutermostType,
3652                                            bool EncodingProperty) {
3653  if (T->getAs<BuiltinType>()) {
3654    if (FD && FD->isBitField())
3655      return EncodeBitField(this, S, T, FD);
3656    S += ObjCEncodingForPrimitiveKind(this, T);
3657    return;
3658  }
3659
3660  if (const ComplexType *CT = T->getAs<ComplexType>()) {
3661    S += 'j';
3662    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
3663                               false);
3664    return;
3665  }
3666
3667  // encoding for pointer or r3eference types.
3668  QualType PointeeTy;
3669  if (const PointerType *PT = T->getAs<PointerType>()) {
3670    if (PT->isObjCSelType()) {
3671      S += ':';
3672      return;
3673    }
3674    PointeeTy = PT->getPointeeType();
3675  }
3676  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3677    PointeeTy = RT->getPointeeType();
3678  if (!PointeeTy.isNull()) {
3679    bool isReadOnly = false;
3680    // For historical/compatibility reasons, the read-only qualifier of the
3681    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
3682    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
3683    // Also, do not emit the 'r' for anything but the outermost type!
3684    if (isa<TypedefType>(T.getTypePtr())) {
3685      if (OutermostType && T.isConstQualified()) {
3686        isReadOnly = true;
3687        S += 'r';
3688      }
3689    } else if (OutermostType) {
3690      QualType P = PointeeTy;
3691      while (P->getAs<PointerType>())
3692        P = P->getAs<PointerType>()->getPointeeType();
3693      if (P.isConstQualified()) {
3694        isReadOnly = true;
3695        S += 'r';
3696      }
3697    }
3698    if (isReadOnly) {
3699      // Another legacy compatibility encoding. Some ObjC qualifier and type
3700      // combinations need to be rearranged.
3701      // Rewrite "in const" from "nr" to "rn"
3702      if (llvm::StringRef(S).endswith("nr"))
3703        S.replace(S.end()-2, S.end(), "rn");
3704    }
3705
3706    if (PointeeTy->isCharType()) {
3707      // char pointer types should be encoded as '*' unless it is a
3708      // type that has been typedef'd to 'BOOL'.
3709      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
3710        S += '*';
3711        return;
3712      }
3713    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
3714      // GCC binary compat: Need to convert "struct objc_class *" to "#".
3715      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
3716        S += '#';
3717        return;
3718      }
3719      // GCC binary compat: Need to convert "struct objc_object *" to "@".
3720      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
3721        S += '@';
3722        return;
3723      }
3724      // fall through...
3725    }
3726    S += '^';
3727    getLegacyIntegralTypeEncoding(PointeeTy);
3728
3729    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
3730                               NULL);
3731    return;
3732  }
3733
3734  if (const ArrayType *AT =
3735      // Ignore type qualifiers etc.
3736        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
3737    if (isa<IncompleteArrayType>(AT)) {
3738      // Incomplete arrays are encoded as a pointer to the array element.
3739      S += '^';
3740
3741      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3742                                 false, ExpandStructures, FD);
3743    } else {
3744      S += '[';
3745
3746      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
3747        S += llvm::utostr(CAT->getSize().getZExtValue());
3748      else {
3749        //Variable length arrays are encoded as a regular array with 0 elements.
3750        assert(isa<VariableArrayType>(AT) && "Unknown array type!");
3751        S += '0';
3752      }
3753
3754      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3755                                 false, ExpandStructures, FD);
3756      S += ']';
3757    }
3758    return;
3759  }
3760
3761  if (T->getAs<FunctionType>()) {
3762    S += '?';
3763    return;
3764  }
3765
3766  if (const RecordType *RTy = T->getAs<RecordType>()) {
3767    RecordDecl *RDecl = RTy->getDecl();
3768    S += RDecl->isUnion() ? '(' : '{';
3769    // Anonymous structures print as '?'
3770    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
3771      S += II->getName();
3772      if (ClassTemplateSpecializationDecl *Spec
3773          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
3774        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
3775        std::string TemplateArgsStr
3776          = TemplateSpecializationType::PrintTemplateArgumentList(
3777                                            TemplateArgs.getFlatArgumentList(),
3778                                            TemplateArgs.flat_size(),
3779                                            (*this).PrintingPolicy);
3780
3781        S += TemplateArgsStr;
3782      }
3783    } else {
3784      S += '?';
3785    }
3786    if (ExpandStructures) {
3787      S += '=';
3788      for (RecordDecl::field_iterator Field = RDecl->field_begin(),
3789                                   FieldEnd = RDecl->field_end();
3790           Field != FieldEnd; ++Field) {
3791        if (FD) {
3792          S += '"';
3793          S += Field->getNameAsString();
3794          S += '"';
3795        }
3796
3797        // Special case bit-fields.
3798        if (Field->isBitField()) {
3799          getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
3800                                     (*Field));
3801        } else {
3802          QualType qt = Field->getType();
3803          getLegacyIntegralTypeEncoding(qt);
3804          getObjCEncodingForTypeImpl(qt, S, false, true,
3805                                     FD);
3806        }
3807      }
3808    }
3809    S += RDecl->isUnion() ? ')' : '}';
3810    return;
3811  }
3812
3813  if (T->isEnumeralType()) {
3814    if (FD && FD->isBitField())
3815      EncodeBitField(this, S, T, FD);
3816    else
3817      S += 'i';
3818    return;
3819  }
3820
3821  if (T->isBlockPointerType()) {
3822    S += "@?"; // Unlike a pointer-to-function, which is "^?".
3823    return;
3824  }
3825
3826  // Ignore protocol qualifiers when mangling at this level.
3827  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
3828    T = OT->getBaseType();
3829
3830  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
3831    // @encode(class_name)
3832    ObjCInterfaceDecl *OI = OIT->getDecl();
3833    S += '{';
3834    const IdentifierInfo *II = OI->getIdentifier();
3835    S += II->getName();
3836    S += '=';
3837    llvm::SmallVector<ObjCIvarDecl*, 32> Ivars;
3838    DeepCollectObjCIvars(OI, true, Ivars);
3839    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
3840      FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
3841      if (Field->isBitField())
3842        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
3843      else
3844        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
3845    }
3846    S += '}';
3847    return;
3848  }
3849
3850  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
3851    if (OPT->isObjCIdType()) {
3852      S += '@';
3853      return;
3854    }
3855
3856    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
3857      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
3858      // Since this is a binary compatibility issue, need to consult with runtime
3859      // folks. Fortunately, this is a *very* obsure construct.
3860      S += '#';
3861      return;
3862    }
3863
3864    if (OPT->isObjCQualifiedIdType()) {
3865      getObjCEncodingForTypeImpl(getObjCIdType(), S,
3866                                 ExpandPointedToStructures,
3867                                 ExpandStructures, FD);
3868      if (FD || EncodingProperty) {
3869        // Note that we do extended encoding of protocol qualifer list
3870        // Only when doing ivar or property encoding.
3871        S += '"';
3872        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3873             E = OPT->qual_end(); I != E; ++I) {
3874          S += '<';
3875          S += (*I)->getNameAsString();
3876          S += '>';
3877        }
3878        S += '"';
3879      }
3880      return;
3881    }
3882
3883    QualType PointeeTy = OPT->getPointeeType();
3884    if (!EncodingProperty &&
3885        isa<TypedefType>(PointeeTy.getTypePtr())) {
3886      // Another historical/compatibility reason.
3887      // We encode the underlying type which comes out as
3888      // {...};
3889      S += '^';
3890      getObjCEncodingForTypeImpl(PointeeTy, S,
3891                                 false, ExpandPointedToStructures,
3892                                 NULL);
3893      return;
3894    }
3895
3896    S += '@';
3897    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
3898      S += '"';
3899      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
3900      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3901           E = OPT->qual_end(); I != E; ++I) {
3902        S += '<';
3903        S += (*I)->getNameAsString();
3904        S += '>';
3905      }
3906      S += '"';
3907    }
3908    return;
3909  }
3910
3911  // gcc just blithely ignores member pointers.
3912  // TODO: maybe there should be a mangling for these
3913  if (T->getAs<MemberPointerType>())
3914    return;
3915
3916  assert(0 && "@encode for type not implemented!");
3917}
3918
3919void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
3920                                                 std::string& S) const {
3921  if (QT & Decl::OBJC_TQ_In)
3922    S += 'n';
3923  if (QT & Decl::OBJC_TQ_Inout)
3924    S += 'N';
3925  if (QT & Decl::OBJC_TQ_Out)
3926    S += 'o';
3927  if (QT & Decl::OBJC_TQ_Bycopy)
3928    S += 'O';
3929  if (QT & Decl::OBJC_TQ_Byref)
3930    S += 'R';
3931  if (QT & Decl::OBJC_TQ_Oneway)
3932    S += 'V';
3933}
3934
3935void ASTContext::setBuiltinVaListType(QualType T) {
3936  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
3937
3938  BuiltinVaListType = T;
3939}
3940
3941void ASTContext::setObjCIdType(QualType T) {
3942  ObjCIdTypedefType = T;
3943}
3944
3945void ASTContext::setObjCSelType(QualType T) {
3946  ObjCSelTypedefType = T;
3947}
3948
3949void ASTContext::setObjCProtoType(QualType QT) {
3950  ObjCProtoType = QT;
3951}
3952
3953void ASTContext::setObjCClassType(QualType T) {
3954  ObjCClassTypedefType = T;
3955}
3956
3957void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
3958  assert(ObjCConstantStringType.isNull() &&
3959         "'NSConstantString' type already set!");
3960
3961  ObjCConstantStringType = getObjCInterfaceType(Decl);
3962}
3963
3964/// \brief Retrieve the template name that corresponds to a non-empty
3965/// lookup.
3966TemplateName ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
3967                                                   UnresolvedSetIterator End) {
3968  unsigned size = End - Begin;
3969  assert(size > 1 && "set is not overloaded!");
3970
3971  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
3972                          size * sizeof(FunctionTemplateDecl*));
3973  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
3974
3975  NamedDecl **Storage = OT->getStorage();
3976  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
3977    NamedDecl *D = *I;
3978    assert(isa<FunctionTemplateDecl>(D) ||
3979           (isa<UsingShadowDecl>(D) &&
3980            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
3981    *Storage++ = D;
3982  }
3983
3984  return TemplateName(OT);
3985}
3986
3987/// \brief Retrieve the template name that represents a qualified
3988/// template name such as \c std::vector.
3989TemplateName ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
3990                                                  bool TemplateKeyword,
3991                                                  TemplateDecl *Template) {
3992  // FIXME: Canonicalization?
3993  llvm::FoldingSetNodeID ID;
3994  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
3995
3996  void *InsertPos = 0;
3997  QualifiedTemplateName *QTN =
3998    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
3999  if (!QTN) {
4000    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4001    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4002  }
4003
4004  return TemplateName(QTN);
4005}
4006
4007/// \brief Retrieve the template name that represents a dependent
4008/// template name such as \c MetaFun::template apply.
4009TemplateName ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4010                                                  const IdentifierInfo *Name) {
4011  assert((!NNS || NNS->isDependent()) &&
4012         "Nested name specifier must be dependent");
4013
4014  llvm::FoldingSetNodeID ID;
4015  DependentTemplateName::Profile(ID, NNS, Name);
4016
4017  void *InsertPos = 0;
4018  DependentTemplateName *QTN =
4019    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4020
4021  if (QTN)
4022    return TemplateName(QTN);
4023
4024  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4025  if (CanonNNS == NNS) {
4026    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4027  } else {
4028    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4029    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4030    DependentTemplateName *CheckQTN =
4031      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4032    assert(!CheckQTN && "Dependent type name canonicalization broken");
4033    (void)CheckQTN;
4034  }
4035
4036  DependentTemplateNames.InsertNode(QTN, InsertPos);
4037  return TemplateName(QTN);
4038}
4039
4040/// \brief Retrieve the template name that represents a dependent
4041/// template name such as \c MetaFun::template operator+.
4042TemplateName
4043ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4044                                     OverloadedOperatorKind Operator) {
4045  assert((!NNS || NNS->isDependent()) &&
4046         "Nested name specifier must be dependent");
4047
4048  llvm::FoldingSetNodeID ID;
4049  DependentTemplateName::Profile(ID, NNS, Operator);
4050
4051  void *InsertPos = 0;
4052  DependentTemplateName *QTN
4053    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4054
4055  if (QTN)
4056    return TemplateName(QTN);
4057
4058  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4059  if (CanonNNS == NNS) {
4060    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4061  } else {
4062    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4063    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4064
4065    DependentTemplateName *CheckQTN
4066      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4067    assert(!CheckQTN && "Dependent template name canonicalization broken");
4068    (void)CheckQTN;
4069  }
4070
4071  DependentTemplateNames.InsertNode(QTN, InsertPos);
4072  return TemplateName(QTN);
4073}
4074
4075/// getFromTargetType - Given one of the integer types provided by
4076/// TargetInfo, produce the corresponding type. The unsigned @p Type
4077/// is actually a value of type @c TargetInfo::IntType.
4078CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4079  switch (Type) {
4080  case TargetInfo::NoInt: return CanQualType();
4081  case TargetInfo::SignedShort: return ShortTy;
4082  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4083  case TargetInfo::SignedInt: return IntTy;
4084  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4085  case TargetInfo::SignedLong: return LongTy;
4086  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4087  case TargetInfo::SignedLongLong: return LongLongTy;
4088  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4089  }
4090
4091  assert(false && "Unhandled TargetInfo::IntType value");
4092  return CanQualType();
4093}
4094
4095//===----------------------------------------------------------------------===//
4096//                        Type Predicates.
4097//===----------------------------------------------------------------------===//
4098
4099/// isObjCNSObjectType - Return true if this is an NSObject object using
4100/// NSObject attribute on a c-style pointer type.
4101/// FIXME - Make it work directly on types.
4102/// FIXME: Move to Type.
4103///
4104bool ASTContext::isObjCNSObjectType(QualType Ty) const {
4105  if (TypedefType *TDT = dyn_cast<TypedefType>(Ty)) {
4106    if (TypedefDecl *TD = TDT->getDecl())
4107      if (TD->getAttr<ObjCNSObjectAttr>())
4108        return true;
4109  }
4110  return false;
4111}
4112
4113/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4114/// garbage collection attribute.
4115///
4116Qualifiers::GC ASTContext::getObjCGCAttrKind(const QualType &Ty) const {
4117  Qualifiers::GC GCAttrs = Qualifiers::GCNone;
4118  if (getLangOptions().ObjC1 &&
4119      getLangOptions().getGCMode() != LangOptions::NonGC) {
4120    GCAttrs = Ty.getObjCGCAttr();
4121    // Default behavious under objective-c's gc is for objective-c pointers
4122    // (or pointers to them) be treated as though they were declared
4123    // as __strong.
4124    if (GCAttrs == Qualifiers::GCNone) {
4125      if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4126        GCAttrs = Qualifiers::Strong;
4127      else if (Ty->isPointerType())
4128        return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4129    }
4130    // Non-pointers have none gc'able attribute regardless of the attribute
4131    // set on them.
4132    else if (!Ty->isAnyPointerType() && !Ty->isBlockPointerType())
4133      return Qualifiers::GCNone;
4134  }
4135  return GCAttrs;
4136}
4137
4138//===----------------------------------------------------------------------===//
4139//                        Type Compatibility Testing
4140//===----------------------------------------------------------------------===//
4141
4142/// areCompatVectorTypes - Return true if the two specified vector types are
4143/// compatible.
4144static bool areCompatVectorTypes(const VectorType *LHS,
4145                                 const VectorType *RHS) {
4146  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
4147  return LHS->getElementType() == RHS->getElementType() &&
4148         LHS->getNumElements() == RHS->getNumElements();
4149}
4150
4151bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
4152                                          QualType SecondVec) {
4153  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
4154  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
4155
4156  if (hasSameUnqualifiedType(FirstVec, SecondVec))
4157    return true;
4158
4159  // AltiVec vectors types are identical to equivalent GCC vector types
4160  const VectorType *First = FirstVec->getAs<VectorType>();
4161  const VectorType *Second = SecondVec->getAs<VectorType>();
4162  if ((((First->getAltiVecSpecific() == VectorType::AltiVec) &&
4163        (Second->getAltiVecSpecific() == VectorType::NotAltiVec)) ||
4164       ((First->getAltiVecSpecific() == VectorType::NotAltiVec) &&
4165        (Second->getAltiVecSpecific() == VectorType::AltiVec))) &&
4166      hasSameType(First->getElementType(), Second->getElementType()) &&
4167      (First->getNumElements() == Second->getNumElements()))
4168    return true;
4169
4170  return false;
4171}
4172
4173//===----------------------------------------------------------------------===//
4174// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
4175//===----------------------------------------------------------------------===//
4176
4177/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
4178/// inheritance hierarchy of 'rProto'.
4179bool ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
4180                                                ObjCProtocolDecl *rProto) {
4181  if (lProto == rProto)
4182    return true;
4183  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
4184       E = rProto->protocol_end(); PI != E; ++PI)
4185    if (ProtocolCompatibleWithProtocol(lProto, *PI))
4186      return true;
4187  return false;
4188}
4189
4190/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
4191/// return true if lhs's protocols conform to rhs's protocol; false
4192/// otherwise.
4193bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
4194  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
4195    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
4196  return false;
4197}
4198
4199/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
4200/// Class<p1, ...>.
4201bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
4202                                                      QualType rhs) {
4203  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
4204  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4205  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
4206
4207  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4208       E = lhsQID->qual_end(); I != E; ++I) {
4209    bool match = false;
4210    ObjCProtocolDecl *lhsProto = *I;
4211    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4212         E = rhsOPT->qual_end(); J != E; ++J) {
4213      ObjCProtocolDecl *rhsProto = *J;
4214      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
4215        match = true;
4216        break;
4217      }
4218    }
4219    if (!match)
4220      return false;
4221  }
4222  return true;
4223}
4224
4225/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
4226/// ObjCQualifiedIDType.
4227bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
4228                                                   bool compare) {
4229  // Allow id<P..> and an 'id' or void* type in all cases.
4230  if (lhs->isVoidPointerType() ||
4231      lhs->isObjCIdType() || lhs->isObjCClassType())
4232    return true;
4233  else if (rhs->isVoidPointerType() ||
4234           rhs->isObjCIdType() || rhs->isObjCClassType())
4235    return true;
4236
4237  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
4238    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4239
4240    if (!rhsOPT) return false;
4241
4242    if (rhsOPT->qual_empty()) {
4243      // If the RHS is a unqualified interface pointer "NSString*",
4244      // make sure we check the class hierarchy.
4245      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4246        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4247             E = lhsQID->qual_end(); I != E; ++I) {
4248          // when comparing an id<P> on lhs with a static type on rhs,
4249          // see if static class implements all of id's protocols, directly or
4250          // through its super class and categories.
4251          if (!rhsID->ClassImplementsProtocol(*I, true))
4252            return false;
4253        }
4254      }
4255      // If there are no qualifiers and no interface, we have an 'id'.
4256      return true;
4257    }
4258    // Both the right and left sides have qualifiers.
4259    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4260         E = lhsQID->qual_end(); I != E; ++I) {
4261      ObjCProtocolDecl *lhsProto = *I;
4262      bool match = false;
4263
4264      // when comparing an id<P> on lhs with a static type on rhs,
4265      // see if static class implements all of id's protocols, directly or
4266      // through its super class and categories.
4267      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4268           E = rhsOPT->qual_end(); J != E; ++J) {
4269        ObjCProtocolDecl *rhsProto = *J;
4270        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4271            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4272          match = true;
4273          break;
4274        }
4275      }
4276      // If the RHS is a qualified interface pointer "NSString<P>*",
4277      // make sure we check the class hierarchy.
4278      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4279        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4280             E = lhsQID->qual_end(); I != E; ++I) {
4281          // when comparing an id<P> on lhs with a static type on rhs,
4282          // see if static class implements all of id's protocols, directly or
4283          // through its super class and categories.
4284          if (rhsID->ClassImplementsProtocol(*I, true)) {
4285            match = true;
4286            break;
4287          }
4288        }
4289      }
4290      if (!match)
4291        return false;
4292    }
4293
4294    return true;
4295  }
4296
4297  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
4298  assert(rhsQID && "One of the LHS/RHS should be id<x>");
4299
4300  if (const ObjCObjectPointerType *lhsOPT =
4301        lhs->getAsObjCInterfacePointerType()) {
4302    if (lhsOPT->qual_empty()) {
4303      bool match = false;
4304      if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
4305        for (ObjCObjectPointerType::qual_iterator I = rhsQID->qual_begin(),
4306             E = rhsQID->qual_end(); I != E; ++I) {
4307          // when comparing an id<P> on rhs with a static type on lhs,
4308          // static class must implement all of id's protocols directly or
4309          // indirectly through its super class.
4310          if (lhsID->ClassImplementsProtocol(*I, true)) {
4311            match = true;
4312            break;
4313          }
4314        }
4315        if (!match)
4316          return false;
4317      }
4318      return true;
4319    }
4320    // Both the right and left sides have qualifiers.
4321    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
4322         E = lhsOPT->qual_end(); I != E; ++I) {
4323      ObjCProtocolDecl *lhsProto = *I;
4324      bool match = false;
4325
4326      // when comparing an id<P> on lhs with a static type on rhs,
4327      // see if static class implements all of id's protocols, directly or
4328      // through its super class and categories.
4329      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4330           E = rhsQID->qual_end(); J != E; ++J) {
4331        ObjCProtocolDecl *rhsProto = *J;
4332        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4333            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4334          match = true;
4335          break;
4336        }
4337      }
4338      if (!match)
4339        return false;
4340    }
4341    return true;
4342  }
4343  return false;
4344}
4345
4346/// canAssignObjCInterfaces - Return true if the two interface types are
4347/// compatible for assignment from RHS to LHS.  This handles validation of any
4348/// protocol qualifiers on the LHS or RHS.
4349///
4350bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
4351                                         const ObjCObjectPointerType *RHSOPT) {
4352  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4353  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4354
4355  // If either type represents the built-in 'id' or 'Class' types, return true.
4356  if (LHS->isObjCUnqualifiedIdOrClass() ||
4357      RHS->isObjCUnqualifiedIdOrClass())
4358    return true;
4359
4360  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
4361    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4362                                             QualType(RHSOPT,0),
4363                                             false);
4364
4365  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
4366    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
4367                                                QualType(RHSOPT,0));
4368
4369  // If we have 2 user-defined types, fall into that path.
4370  if (LHS->getInterface() && RHS->getInterface())
4371    return canAssignObjCInterfaces(LHS, RHS);
4372
4373  return false;
4374}
4375
4376/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
4377/// for providing type-safty for objective-c pointers used to pass/return
4378/// arguments in block literals. When passed as arguments, passing 'A*' where
4379/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
4380/// not OK. For the return type, the opposite is not OK.
4381bool ASTContext::canAssignObjCInterfacesInBlockPointer(
4382                                         const ObjCObjectPointerType *LHSOPT,
4383                                         const ObjCObjectPointerType *RHSOPT) {
4384  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
4385    return true;
4386
4387  if (LHSOPT->isObjCBuiltinType()) {
4388    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
4389  }
4390
4391  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
4392    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4393                                             QualType(RHSOPT,0),
4394                                             false);
4395
4396  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
4397  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
4398  if (LHS && RHS)  { // We have 2 user-defined types.
4399    if (LHS != RHS) {
4400      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
4401        return false;
4402      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
4403        return true;
4404    }
4405    else
4406      return true;
4407  }
4408  return false;
4409}
4410
4411/// getIntersectionOfProtocols - This routine finds the intersection of set
4412/// of protocols inherited from two distinct objective-c pointer objects.
4413/// It is used to build composite qualifier list of the composite type of
4414/// the conditional expression involving two objective-c pointer objects.
4415static
4416void getIntersectionOfProtocols(ASTContext &Context,
4417                                const ObjCObjectPointerType *LHSOPT,
4418                                const ObjCObjectPointerType *RHSOPT,
4419      llvm::SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
4420
4421  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4422  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4423  assert(LHS->getInterface() && "LHS must have an interface base");
4424  assert(RHS->getInterface() && "RHS must have an interface base");
4425
4426  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
4427  unsigned LHSNumProtocols = LHS->getNumProtocols();
4428  if (LHSNumProtocols > 0)
4429    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
4430  else {
4431    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4432    Context.CollectInheritedProtocols(LHS->getInterface(),
4433                                      LHSInheritedProtocols);
4434    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
4435                                LHSInheritedProtocols.end());
4436  }
4437
4438  unsigned RHSNumProtocols = RHS->getNumProtocols();
4439  if (RHSNumProtocols > 0) {
4440    ObjCProtocolDecl **RHSProtocols =
4441      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
4442    for (unsigned i = 0; i < RHSNumProtocols; ++i)
4443      if (InheritedProtocolSet.count(RHSProtocols[i]))
4444        IntersectionOfProtocols.push_back(RHSProtocols[i]);
4445  }
4446  else {
4447    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
4448    Context.CollectInheritedProtocols(RHS->getInterface(),
4449                                      RHSInheritedProtocols);
4450    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4451         RHSInheritedProtocols.begin(),
4452         E = RHSInheritedProtocols.end(); I != E; ++I)
4453      if (InheritedProtocolSet.count((*I)))
4454        IntersectionOfProtocols.push_back((*I));
4455  }
4456}
4457
4458/// areCommonBaseCompatible - Returns common base class of the two classes if
4459/// one found. Note that this is O'2 algorithm. But it will be called as the
4460/// last type comparison in a ?-exp of ObjC pointer types before a
4461/// warning is issued. So, its invokation is extremely rare.
4462QualType ASTContext::areCommonBaseCompatible(
4463                                          const ObjCObjectPointerType *Lptr,
4464                                          const ObjCObjectPointerType *Rptr) {
4465  const ObjCObjectType *LHS = Lptr->getObjectType();
4466  const ObjCObjectType *RHS = Rptr->getObjectType();
4467  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
4468  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
4469  if (!LDecl || !RDecl)
4470    return QualType();
4471
4472  while ((LDecl = LDecl->getSuperClass())) {
4473    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
4474    if (canAssignObjCInterfaces(LHS, RHS)) {
4475      llvm::SmallVector<ObjCProtocolDecl *, 8> Protocols;
4476      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
4477
4478      QualType Result = QualType(LHS, 0);
4479      if (!Protocols.empty())
4480        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
4481      Result = getObjCObjectPointerType(Result);
4482      return Result;
4483    }
4484  }
4485
4486  return QualType();
4487}
4488
4489bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
4490                                         const ObjCObjectType *RHS) {
4491  assert(LHS->getInterface() && "LHS is not an interface type");
4492  assert(RHS->getInterface() && "RHS is not an interface type");
4493
4494  // Verify that the base decls are compatible: the RHS must be a subclass of
4495  // the LHS.
4496  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
4497    return false;
4498
4499  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
4500  // protocol qualified at all, then we are good.
4501  if (LHS->getNumProtocols() == 0)
4502    return true;
4503
4504  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't, then it
4505  // isn't a superset.
4506  if (RHS->getNumProtocols() == 0)
4507    return true;  // FIXME: should return false!
4508
4509  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
4510                                     LHSPE = LHS->qual_end();
4511       LHSPI != LHSPE; LHSPI++) {
4512    bool RHSImplementsProtocol = false;
4513
4514    // If the RHS doesn't implement the protocol on the left, the types
4515    // are incompatible.
4516    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
4517                                       RHSPE = RHS->qual_end();
4518         RHSPI != RHSPE; RHSPI++) {
4519      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
4520        RHSImplementsProtocol = true;
4521        break;
4522      }
4523    }
4524    // FIXME: For better diagnostics, consider passing back the protocol name.
4525    if (!RHSImplementsProtocol)
4526      return false;
4527  }
4528  // The RHS implements all protocols listed on the LHS.
4529  return true;
4530}
4531
4532bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
4533  // get the "pointed to" types
4534  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
4535  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
4536
4537  if (!LHSOPT || !RHSOPT)
4538    return false;
4539
4540  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
4541         canAssignObjCInterfaces(RHSOPT, LHSOPT);
4542}
4543
4544bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
4545  return canAssignObjCInterfaces(
4546                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
4547                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
4548}
4549
4550/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
4551/// both shall have the identically qualified version of a compatible type.
4552/// C99 6.2.7p1: Two types have compatible types if their types are the
4553/// same. See 6.7.[2,3,5] for additional rules.
4554bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
4555                                    bool CompareUnqualified) {
4556  if (getLangOptions().CPlusPlus)
4557    return hasSameType(LHS, RHS);
4558
4559  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
4560}
4561
4562bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
4563  return !mergeTypes(LHS, RHS, true).isNull();
4564}
4565
4566QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
4567                                        bool OfBlockPointer,
4568                                        bool Unqualified) {
4569  const FunctionType *lbase = lhs->getAs<FunctionType>();
4570  const FunctionType *rbase = rhs->getAs<FunctionType>();
4571  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
4572  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
4573  bool allLTypes = true;
4574  bool allRTypes = true;
4575
4576  // Check return type
4577  QualType retType;
4578  if (OfBlockPointer)
4579    retType = mergeTypes(rbase->getResultType(), lbase->getResultType(), true,
4580                         Unqualified);
4581  else
4582   retType = mergeTypes(lbase->getResultType(), rbase->getResultType(),
4583                        false, Unqualified);
4584  if (retType.isNull()) return QualType();
4585
4586  if (Unqualified)
4587    retType = retType.getUnqualifiedType();
4588
4589  CanQualType LRetType = getCanonicalType(lbase->getResultType());
4590  CanQualType RRetType = getCanonicalType(rbase->getResultType());
4591  if (Unqualified) {
4592    LRetType = LRetType.getUnqualifiedType();
4593    RRetType = RRetType.getUnqualifiedType();
4594  }
4595
4596  if (getCanonicalType(retType) != LRetType)
4597    allLTypes = false;
4598  if (getCanonicalType(retType) != RRetType)
4599    allRTypes = false;
4600  // FIXME: double check this
4601  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
4602  //                           rbase->getRegParmAttr() != 0 &&
4603  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
4604  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
4605  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
4606  unsigned RegParm = lbaseInfo.getRegParm() == 0 ? rbaseInfo.getRegParm() :
4607      lbaseInfo.getRegParm();
4608  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
4609  if (NoReturn != lbaseInfo.getNoReturn() ||
4610      RegParm != lbaseInfo.getRegParm())
4611    allLTypes = false;
4612  if (NoReturn != rbaseInfo.getNoReturn() ||
4613      RegParm != rbaseInfo.getRegParm())
4614    allRTypes = false;
4615  CallingConv lcc = lbaseInfo.getCC();
4616  CallingConv rcc = rbaseInfo.getCC();
4617  // Compatible functions must have compatible calling conventions
4618  if (!isSameCallConv(lcc, rcc))
4619    return QualType();
4620
4621  if (lproto && rproto) { // two C99 style function prototypes
4622    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
4623           "C++ shouldn't be here");
4624    unsigned lproto_nargs = lproto->getNumArgs();
4625    unsigned rproto_nargs = rproto->getNumArgs();
4626
4627    // Compatible functions must have the same number of arguments
4628    if (lproto_nargs != rproto_nargs)
4629      return QualType();
4630
4631    // Variadic and non-variadic functions aren't compatible
4632    if (lproto->isVariadic() != rproto->isVariadic())
4633      return QualType();
4634
4635    if (lproto->getTypeQuals() != rproto->getTypeQuals())
4636      return QualType();
4637
4638    // Check argument compatibility
4639    llvm::SmallVector<QualType, 10> types;
4640    for (unsigned i = 0; i < lproto_nargs; i++) {
4641      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
4642      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
4643      QualType argtype = mergeTypes(largtype, rargtype, OfBlockPointer,
4644                                    Unqualified);
4645      if (argtype.isNull()) return QualType();
4646
4647      if (Unqualified)
4648        argtype = argtype.getUnqualifiedType();
4649
4650      types.push_back(argtype);
4651      if (Unqualified) {
4652        largtype = largtype.getUnqualifiedType();
4653        rargtype = rargtype.getUnqualifiedType();
4654      }
4655
4656      if (getCanonicalType(argtype) != getCanonicalType(largtype))
4657        allLTypes = false;
4658      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
4659        allRTypes = false;
4660    }
4661    if (allLTypes) return lhs;
4662    if (allRTypes) return rhs;
4663    return getFunctionType(retType, types.begin(), types.size(),
4664                           lproto->isVariadic(), lproto->getTypeQuals(),
4665                           false, false, 0, 0,
4666                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4667  }
4668
4669  if (lproto) allRTypes = false;
4670  if (rproto) allLTypes = false;
4671
4672  const FunctionProtoType *proto = lproto ? lproto : rproto;
4673  if (proto) {
4674    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
4675    if (proto->isVariadic()) return QualType();
4676    // Check that the types are compatible with the types that
4677    // would result from default argument promotions (C99 6.7.5.3p15).
4678    // The only types actually affected are promotable integer
4679    // types and floats, which would be passed as a different
4680    // type depending on whether the prototype is visible.
4681    unsigned proto_nargs = proto->getNumArgs();
4682    for (unsigned i = 0; i < proto_nargs; ++i) {
4683      QualType argTy = proto->getArgType(i);
4684
4685      // Look at the promotion type of enum types, since that is the type used
4686      // to pass enum values.
4687      if (const EnumType *Enum = argTy->getAs<EnumType>())
4688        argTy = Enum->getDecl()->getPromotionType();
4689
4690      if (argTy->isPromotableIntegerType() ||
4691          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
4692        return QualType();
4693    }
4694
4695    if (allLTypes) return lhs;
4696    if (allRTypes) return rhs;
4697    return getFunctionType(retType, proto->arg_type_begin(),
4698                           proto->getNumArgs(), proto->isVariadic(),
4699                           proto->getTypeQuals(),
4700                           false, false, 0, 0,
4701                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4702  }
4703
4704  if (allLTypes) return lhs;
4705  if (allRTypes) return rhs;
4706  FunctionType::ExtInfo Info(NoReturn, RegParm, lcc);
4707  return getFunctionNoProtoType(retType, Info);
4708}
4709
4710QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
4711                                bool OfBlockPointer,
4712                                bool Unqualified) {
4713  // C++ [expr]: If an expression initially has the type "reference to T", the
4714  // type is adjusted to "T" prior to any further analysis, the expression
4715  // designates the object or function denoted by the reference, and the
4716  // expression is an lvalue unless the reference is an rvalue reference and
4717  // the expression is a function call (possibly inside parentheses).
4718  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
4719  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
4720
4721  if (Unqualified) {
4722    LHS = LHS.getUnqualifiedType();
4723    RHS = RHS.getUnqualifiedType();
4724  }
4725
4726  QualType LHSCan = getCanonicalType(LHS),
4727           RHSCan = getCanonicalType(RHS);
4728
4729  // If two types are identical, they are compatible.
4730  if (LHSCan == RHSCan)
4731    return LHS;
4732
4733  // If the qualifiers are different, the types aren't compatible... mostly.
4734  Qualifiers LQuals = LHSCan.getLocalQualifiers();
4735  Qualifiers RQuals = RHSCan.getLocalQualifiers();
4736  if (LQuals != RQuals) {
4737    // If any of these qualifiers are different, we have a type
4738    // mismatch.
4739    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
4740        LQuals.getAddressSpace() != RQuals.getAddressSpace())
4741      return QualType();
4742
4743    // Exactly one GC qualifier difference is allowed: __strong is
4744    // okay if the other type has no GC qualifier but is an Objective
4745    // C object pointer (i.e. implicitly strong by default).  We fix
4746    // this by pretending that the unqualified type was actually
4747    // qualified __strong.
4748    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
4749    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
4750    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
4751
4752    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
4753      return QualType();
4754
4755    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
4756      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
4757    }
4758    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
4759      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
4760    }
4761    return QualType();
4762  }
4763
4764  // Okay, qualifiers are equal.
4765
4766  Type::TypeClass LHSClass = LHSCan->getTypeClass();
4767  Type::TypeClass RHSClass = RHSCan->getTypeClass();
4768
4769  // We want to consider the two function types to be the same for these
4770  // comparisons, just force one to the other.
4771  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
4772  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
4773
4774  // Same as above for arrays
4775  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
4776    LHSClass = Type::ConstantArray;
4777  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
4778    RHSClass = Type::ConstantArray;
4779
4780  // ObjCInterfaces are just specialized ObjCObjects.
4781  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
4782  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
4783
4784  // Canonicalize ExtVector -> Vector.
4785  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
4786  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
4787
4788  // If the canonical type classes don't match.
4789  if (LHSClass != RHSClass) {
4790    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
4791    // a signed integer type, or an unsigned integer type.
4792    // Compatibility is based on the underlying type, not the promotion
4793    // type.
4794    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
4795      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
4796        return RHS;
4797    }
4798    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
4799      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
4800        return LHS;
4801    }
4802
4803    return QualType();
4804  }
4805
4806  // The canonical type classes match.
4807  switch (LHSClass) {
4808#define TYPE(Class, Base)
4809#define ABSTRACT_TYPE(Class, Base)
4810#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
4811#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
4812#define DEPENDENT_TYPE(Class, Base) case Type::Class:
4813#include "clang/AST/TypeNodes.def"
4814    assert(false && "Non-canonical and dependent types shouldn't get here");
4815    return QualType();
4816
4817  case Type::LValueReference:
4818  case Type::RValueReference:
4819  case Type::MemberPointer:
4820    assert(false && "C++ should never be in mergeTypes");
4821    return QualType();
4822
4823  case Type::ObjCInterface:
4824  case Type::IncompleteArray:
4825  case Type::VariableArray:
4826  case Type::FunctionProto:
4827  case Type::ExtVector:
4828    assert(false && "Types are eliminated above");
4829    return QualType();
4830
4831  case Type::Pointer:
4832  {
4833    // Merge two pointer types, while trying to preserve typedef info
4834    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
4835    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
4836    if (Unqualified) {
4837      LHSPointee = LHSPointee.getUnqualifiedType();
4838      RHSPointee = RHSPointee.getUnqualifiedType();
4839    }
4840    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
4841                                     Unqualified);
4842    if (ResultType.isNull()) return QualType();
4843    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
4844      return LHS;
4845    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
4846      return RHS;
4847    return getPointerType(ResultType);
4848  }
4849  case Type::BlockPointer:
4850  {
4851    // Merge two block pointer types, while trying to preserve typedef info
4852    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
4853    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
4854    if (Unqualified) {
4855      LHSPointee = LHSPointee.getUnqualifiedType();
4856      RHSPointee = RHSPointee.getUnqualifiedType();
4857    }
4858    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
4859                                     Unqualified);
4860    if (ResultType.isNull()) return QualType();
4861    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
4862      return LHS;
4863    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
4864      return RHS;
4865    return getBlockPointerType(ResultType);
4866  }
4867  case Type::ConstantArray:
4868  {
4869    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
4870    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
4871    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
4872      return QualType();
4873
4874    QualType LHSElem = getAsArrayType(LHS)->getElementType();
4875    QualType RHSElem = getAsArrayType(RHS)->getElementType();
4876    if (Unqualified) {
4877      LHSElem = LHSElem.getUnqualifiedType();
4878      RHSElem = RHSElem.getUnqualifiedType();
4879    }
4880
4881    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
4882    if (ResultType.isNull()) return QualType();
4883    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
4884      return LHS;
4885    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
4886      return RHS;
4887    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
4888                                          ArrayType::ArraySizeModifier(), 0);
4889    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
4890                                          ArrayType::ArraySizeModifier(), 0);
4891    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
4892    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
4893    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
4894      return LHS;
4895    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
4896      return RHS;
4897    if (LVAT) {
4898      // FIXME: This isn't correct! But tricky to implement because
4899      // the array's size has to be the size of LHS, but the type
4900      // has to be different.
4901      return LHS;
4902    }
4903    if (RVAT) {
4904      // FIXME: This isn't correct! But tricky to implement because
4905      // the array's size has to be the size of RHS, but the type
4906      // has to be different.
4907      return RHS;
4908    }
4909    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
4910    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
4911    return getIncompleteArrayType(ResultType,
4912                                  ArrayType::ArraySizeModifier(), 0);
4913  }
4914  case Type::FunctionNoProto:
4915    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
4916  case Type::Record:
4917  case Type::Enum:
4918    return QualType();
4919  case Type::Builtin:
4920    // Only exactly equal builtin types are compatible, which is tested above.
4921    return QualType();
4922  case Type::Complex:
4923    // Distinct complex types are incompatible.
4924    return QualType();
4925  case Type::Vector:
4926    // FIXME: The merged type should be an ExtVector!
4927    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
4928                             RHSCan->getAs<VectorType>()))
4929      return LHS;
4930    return QualType();
4931  case Type::ObjCObject: {
4932    // Check if the types are assignment compatible.
4933    // FIXME: This should be type compatibility, e.g. whether
4934    // "LHS x; RHS x;" at global scope is legal.
4935    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
4936    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
4937    if (canAssignObjCInterfaces(LHSIface, RHSIface))
4938      return LHS;
4939
4940    return QualType();
4941  }
4942  case Type::ObjCObjectPointer: {
4943    if (OfBlockPointer) {
4944      if (canAssignObjCInterfacesInBlockPointer(
4945                                          LHS->getAs<ObjCObjectPointerType>(),
4946                                          RHS->getAs<ObjCObjectPointerType>()))
4947      return LHS;
4948      return QualType();
4949    }
4950    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
4951                                RHS->getAs<ObjCObjectPointerType>()))
4952      return LHS;
4953
4954    return QualType();
4955    }
4956  }
4957
4958  return QualType();
4959}
4960
4961/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
4962/// 'RHS' attributes and returns the merged version; including for function
4963/// return types.
4964QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
4965  QualType LHSCan = getCanonicalType(LHS),
4966  RHSCan = getCanonicalType(RHS);
4967  // If two types are identical, they are compatible.
4968  if (LHSCan == RHSCan)
4969    return LHS;
4970  if (RHSCan->isFunctionType()) {
4971    if (!LHSCan->isFunctionType())
4972      return QualType();
4973    QualType OldReturnType =
4974      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
4975    QualType NewReturnType =
4976      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
4977    QualType ResReturnType =
4978      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
4979    if (ResReturnType.isNull())
4980      return QualType();
4981    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
4982      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
4983      // In either case, use OldReturnType to build the new function type.
4984      const FunctionType *F = LHS->getAs<FunctionType>();
4985      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
4986        FunctionType::ExtInfo Info = getFunctionExtInfo(LHS);
4987        QualType ResultType
4988          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
4989                                  FPT->getNumArgs(), FPT->isVariadic(),
4990                                  FPT->getTypeQuals(),
4991                                  FPT->hasExceptionSpec(),
4992                                  FPT->hasAnyExceptionSpec(),
4993                                  FPT->getNumExceptions(),
4994                                  FPT->exception_begin(),
4995                                  Info);
4996        return ResultType;
4997      }
4998    }
4999    return QualType();
5000  }
5001
5002  // If the qualifiers are different, the types can still be merged.
5003  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5004  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5005  if (LQuals != RQuals) {
5006    // If any of these qualifiers are different, we have a type mismatch.
5007    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5008        LQuals.getAddressSpace() != RQuals.getAddressSpace())
5009      return QualType();
5010
5011    // Exactly one GC qualifier difference is allowed: __strong is
5012    // okay if the other type has no GC qualifier but is an Objective
5013    // C object pointer (i.e. implicitly strong by default).  We fix
5014    // this by pretending that the unqualified type was actually
5015    // qualified __strong.
5016    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5017    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5018    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5019
5020    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5021      return QualType();
5022
5023    if (GC_L == Qualifiers::Strong)
5024      return LHS;
5025    if (GC_R == Qualifiers::Strong)
5026      return RHS;
5027    return QualType();
5028  }
5029
5030  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
5031    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5032    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5033    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
5034    if (ResQT == LHSBaseQT)
5035      return LHS;
5036    if (ResQT == RHSBaseQT)
5037      return RHS;
5038  }
5039  return QualType();
5040}
5041
5042//===----------------------------------------------------------------------===//
5043//                         Integer Predicates
5044//===----------------------------------------------------------------------===//
5045
5046unsigned ASTContext::getIntWidth(QualType T) {
5047  if (T->isBooleanType())
5048    return 1;
5049  if (EnumType *ET = dyn_cast<EnumType>(T))
5050    T = ET->getDecl()->getIntegerType();
5051  // For builtin types, just use the standard type sizing method
5052  return (unsigned)getTypeSize(T);
5053}
5054
5055QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
5056  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
5057
5058  // Turn <4 x signed int> -> <4 x unsigned int>
5059  if (const VectorType *VTy = T->getAs<VectorType>())
5060    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
5061             VTy->getNumElements(), VTy->getAltiVecSpecific());
5062
5063  // For enums, we return the unsigned version of the base type.
5064  if (const EnumType *ETy = T->getAs<EnumType>())
5065    T = ETy->getDecl()->getIntegerType();
5066
5067  const BuiltinType *BTy = T->getAs<BuiltinType>();
5068  assert(BTy && "Unexpected signed integer type");
5069  switch (BTy->getKind()) {
5070  case BuiltinType::Char_S:
5071  case BuiltinType::SChar:
5072    return UnsignedCharTy;
5073  case BuiltinType::Short:
5074    return UnsignedShortTy;
5075  case BuiltinType::Int:
5076    return UnsignedIntTy;
5077  case BuiltinType::Long:
5078    return UnsignedLongTy;
5079  case BuiltinType::LongLong:
5080    return UnsignedLongLongTy;
5081  case BuiltinType::Int128:
5082    return UnsignedInt128Ty;
5083  default:
5084    assert(0 && "Unexpected signed integer type");
5085    return QualType();
5086  }
5087}
5088
5089ExternalASTSource::~ExternalASTSource() { }
5090
5091void ExternalASTSource::PrintStats() { }
5092
5093
5094//===----------------------------------------------------------------------===//
5095//                          Builtin Type Computation
5096//===----------------------------------------------------------------------===//
5097
5098/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
5099/// pointer over the consumed characters.  This returns the resultant type.
5100static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
5101                                  ASTContext::GetBuiltinTypeError &Error,
5102                                  bool AllowTypeModifiers = true) {
5103  // Modifiers.
5104  int HowLong = 0;
5105  bool Signed = false, Unsigned = false;
5106
5107  // Read the modifiers first.
5108  bool Done = false;
5109  while (!Done) {
5110    switch (*Str++) {
5111    default: Done = true; --Str; break;
5112    case 'S':
5113      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
5114      assert(!Signed && "Can't use 'S' modifier multiple times!");
5115      Signed = true;
5116      break;
5117    case 'U':
5118      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
5119      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
5120      Unsigned = true;
5121      break;
5122    case 'L':
5123      assert(HowLong <= 2 && "Can't have LLLL modifier");
5124      ++HowLong;
5125      break;
5126    }
5127  }
5128
5129  QualType Type;
5130
5131  // Read the base type.
5132  switch (*Str++) {
5133  default: assert(0 && "Unknown builtin type letter!");
5134  case 'v':
5135    assert(HowLong == 0 && !Signed && !Unsigned &&
5136           "Bad modifiers used with 'v'!");
5137    Type = Context.VoidTy;
5138    break;
5139  case 'f':
5140    assert(HowLong == 0 && !Signed && !Unsigned &&
5141           "Bad modifiers used with 'f'!");
5142    Type = Context.FloatTy;
5143    break;
5144  case 'd':
5145    assert(HowLong < 2 && !Signed && !Unsigned &&
5146           "Bad modifiers used with 'd'!");
5147    if (HowLong)
5148      Type = Context.LongDoubleTy;
5149    else
5150      Type = Context.DoubleTy;
5151    break;
5152  case 's':
5153    assert(HowLong == 0 && "Bad modifiers used with 's'!");
5154    if (Unsigned)
5155      Type = Context.UnsignedShortTy;
5156    else
5157      Type = Context.ShortTy;
5158    break;
5159  case 'i':
5160    if (HowLong == 3)
5161      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
5162    else if (HowLong == 2)
5163      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
5164    else if (HowLong == 1)
5165      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
5166    else
5167      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
5168    break;
5169  case 'c':
5170    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
5171    if (Signed)
5172      Type = Context.SignedCharTy;
5173    else if (Unsigned)
5174      Type = Context.UnsignedCharTy;
5175    else
5176      Type = Context.CharTy;
5177    break;
5178  case 'b': // boolean
5179    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
5180    Type = Context.BoolTy;
5181    break;
5182  case 'z':  // size_t.
5183    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
5184    Type = Context.getSizeType();
5185    break;
5186  case 'F':
5187    Type = Context.getCFConstantStringType();
5188    break;
5189  case 'a':
5190    Type = Context.getBuiltinVaListType();
5191    assert(!Type.isNull() && "builtin va list type not initialized!");
5192    break;
5193  case 'A':
5194    // This is a "reference" to a va_list; however, what exactly
5195    // this means depends on how va_list is defined. There are two
5196    // different kinds of va_list: ones passed by value, and ones
5197    // passed by reference.  An example of a by-value va_list is
5198    // x86, where va_list is a char*. An example of by-ref va_list
5199    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
5200    // we want this argument to be a char*&; for x86-64, we want
5201    // it to be a __va_list_tag*.
5202    Type = Context.getBuiltinVaListType();
5203    assert(!Type.isNull() && "builtin va list type not initialized!");
5204    if (Type->isArrayType()) {
5205      Type = Context.getArrayDecayedType(Type);
5206    } else {
5207      Type = Context.getLValueReferenceType(Type);
5208    }
5209    break;
5210  case 'V': {
5211    char *End;
5212    unsigned NumElements = strtoul(Str, &End, 10);
5213    assert(End != Str && "Missing vector size");
5214
5215    Str = End;
5216
5217    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, false);
5218    // FIXME: Don't know what to do about AltiVec.
5219    Type = Context.getVectorType(ElementType, NumElements,
5220                                 VectorType::NotAltiVec);
5221    break;
5222  }
5223  case 'X': {
5224    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, false);
5225    Type = Context.getComplexType(ElementType);
5226    break;
5227  }
5228  case 'P':
5229    Type = Context.getFILEType();
5230    if (Type.isNull()) {
5231      Error = ASTContext::GE_Missing_stdio;
5232      return QualType();
5233    }
5234    break;
5235  case 'J':
5236    if (Signed)
5237      Type = Context.getsigjmp_bufType();
5238    else
5239      Type = Context.getjmp_bufType();
5240
5241    if (Type.isNull()) {
5242      Error = ASTContext::GE_Missing_setjmp;
5243      return QualType();
5244    }
5245    break;
5246  }
5247
5248  if (!AllowTypeModifiers)
5249    return Type;
5250
5251  Done = false;
5252  while (!Done) {
5253    switch (char c = *Str++) {
5254      default: Done = true; --Str; break;
5255      case '*':
5256      case '&':
5257        {
5258          // Both pointers and references can have their pointee types
5259          // qualified with an address space.
5260          char *End;
5261          unsigned AddrSpace = strtoul(Str, &End, 10);
5262          if (End != Str && AddrSpace != 0) {
5263            Type = Context.getAddrSpaceQualType(Type, AddrSpace);
5264            Str = End;
5265          }
5266        }
5267        if (c == '*')
5268          Type = Context.getPointerType(Type);
5269        else
5270          Type = Context.getLValueReferenceType(Type);
5271        break;
5272      // FIXME: There's no way to have a built-in with an rvalue ref arg.
5273      case 'C':
5274        Type = Type.withConst();
5275        break;
5276      case 'D':
5277        Type = Context.getVolatileType(Type);
5278        break;
5279    }
5280  }
5281
5282  return Type;
5283}
5284
5285/// GetBuiltinType - Return the type for the specified builtin.
5286QualType ASTContext::GetBuiltinType(unsigned id,
5287                                    GetBuiltinTypeError &Error) {
5288  const char *TypeStr = BuiltinInfo.GetTypeString(id);
5289
5290  llvm::SmallVector<QualType, 8> ArgTypes;
5291
5292  Error = GE_None;
5293  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error);
5294  if (Error != GE_None)
5295    return QualType();
5296  while (TypeStr[0] && TypeStr[0] != '.') {
5297    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error);
5298    if (Error != GE_None)
5299      return QualType();
5300
5301    // Do array -> pointer decay.  The builtin should use the decayed type.
5302    if (Ty->isArrayType())
5303      Ty = getArrayDecayedType(Ty);
5304
5305    ArgTypes.push_back(Ty);
5306  }
5307
5308  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
5309         "'.' should only occur at end of builtin type list!");
5310
5311  // handle untyped/variadic arguments "T c99Style();" or "T cppStyle(...);".
5312  if (ArgTypes.size() == 0 && TypeStr[0] == '.')
5313    return getFunctionNoProtoType(ResType);
5314
5315  // FIXME: Should we create noreturn types?
5316  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(),
5317                         TypeStr[0] == '.', 0, false, false, 0, 0,
5318                         FunctionType::ExtInfo());
5319}
5320
5321QualType
5322ASTContext::UsualArithmeticConversionsType(QualType lhs, QualType rhs) {
5323  // Perform the usual unary conversions. We do this early so that
5324  // integral promotions to "int" can allow us to exit early, in the
5325  // lhs == rhs check. Also, for conversion purposes, we ignore any
5326  // qualifiers.  For example, "const float" and "float" are
5327  // equivalent.
5328  if (lhs->isPromotableIntegerType())
5329    lhs = getPromotedIntegerType(lhs);
5330  else
5331    lhs = lhs.getUnqualifiedType();
5332  if (rhs->isPromotableIntegerType())
5333    rhs = getPromotedIntegerType(rhs);
5334  else
5335    rhs = rhs.getUnqualifiedType();
5336
5337  // If both types are identical, no conversion is needed.
5338  if (lhs == rhs)
5339    return lhs;
5340
5341  // If either side is a non-arithmetic type (e.g. a pointer), we are done.
5342  // The caller can deal with this (e.g. pointer + int).
5343  if (!lhs->isArithmeticType() || !rhs->isArithmeticType())
5344    return lhs;
5345
5346  // At this point, we have two different arithmetic types.
5347
5348  // Handle complex types first (C99 6.3.1.8p1).
5349  if (lhs->isComplexType() || rhs->isComplexType()) {
5350    // if we have an integer operand, the result is the complex type.
5351    if (rhs->isIntegerType() || rhs->isComplexIntegerType()) {
5352      // convert the rhs to the lhs complex type.
5353      return lhs;
5354    }
5355    if (lhs->isIntegerType() || lhs->isComplexIntegerType()) {
5356      // convert the lhs to the rhs complex type.
5357      return rhs;
5358    }
5359    // This handles complex/complex, complex/float, or float/complex.
5360    // When both operands are complex, the shorter operand is converted to the
5361    // type of the longer, and that is the type of the result. This corresponds
5362    // to what is done when combining two real floating-point operands.
5363    // The fun begins when size promotion occur across type domains.
5364    // From H&S 6.3.4: When one operand is complex and the other is a real
5365    // floating-point type, the less precise type is converted, within it's
5366    // real or complex domain, to the precision of the other type. For example,
5367    // when combining a "long double" with a "double _Complex", the
5368    // "double _Complex" is promoted to "long double _Complex".
5369    int result = getFloatingTypeOrder(lhs, rhs);
5370
5371    if (result > 0) { // The left side is bigger, convert rhs.
5372      rhs = getFloatingTypeOfSizeWithinDomain(lhs, rhs);
5373    } else if (result < 0) { // The right side is bigger, convert lhs.
5374      lhs = getFloatingTypeOfSizeWithinDomain(rhs, lhs);
5375    }
5376    // At this point, lhs and rhs have the same rank/size. Now, make sure the
5377    // domains match. This is a requirement for our implementation, C99
5378    // does not require this promotion.
5379    if (lhs != rhs) { // Domains don't match, we have complex/float mix.
5380      if (lhs->isRealFloatingType()) { // handle "double, _Complex double".
5381        return rhs;
5382      } else { // handle "_Complex double, double".
5383        return lhs;
5384      }
5385    }
5386    return lhs; // The domain/size match exactly.
5387  }
5388  // Now handle "real" floating types (i.e. float, double, long double).
5389  if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) {
5390    // if we have an integer operand, the result is the real floating type.
5391    if (rhs->isIntegerType()) {
5392      // convert rhs to the lhs floating point type.
5393      return lhs;
5394    }
5395    if (rhs->isComplexIntegerType()) {
5396      // convert rhs to the complex floating point type.
5397      return getComplexType(lhs);
5398    }
5399    if (lhs->isIntegerType()) {
5400      // convert lhs to the rhs floating point type.
5401      return rhs;
5402    }
5403    if (lhs->isComplexIntegerType()) {
5404      // convert lhs to the complex floating point type.
5405      return getComplexType(rhs);
5406    }
5407    // We have two real floating types, float/complex combos were handled above.
5408    // Convert the smaller operand to the bigger result.
5409    int result = getFloatingTypeOrder(lhs, rhs);
5410    if (result > 0) // convert the rhs
5411      return lhs;
5412    assert(result < 0 && "illegal float comparison");
5413    return rhs;   // convert the lhs
5414  }
5415  if (lhs->isComplexIntegerType() || rhs->isComplexIntegerType()) {
5416    // Handle GCC complex int extension.
5417    const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType();
5418    const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType();
5419
5420    if (lhsComplexInt && rhsComplexInt) {
5421      if (getIntegerTypeOrder(lhsComplexInt->getElementType(),
5422                              rhsComplexInt->getElementType()) >= 0)
5423        return lhs; // convert the rhs
5424      return rhs;
5425    } else if (lhsComplexInt && rhs->isIntegerType()) {
5426      // convert the rhs to the lhs complex type.
5427      return lhs;
5428    } else if (rhsComplexInt && lhs->isIntegerType()) {
5429      // convert the lhs to the rhs complex type.
5430      return rhs;
5431    }
5432  }
5433  // Finally, we have two differing integer types.
5434  // The rules for this case are in C99 6.3.1.8
5435  int compare = getIntegerTypeOrder(lhs, rhs);
5436  bool lhsSigned = lhs->hasSignedIntegerRepresentation(),
5437       rhsSigned = rhs->hasSignedIntegerRepresentation();
5438  QualType destType;
5439  if (lhsSigned == rhsSigned) {
5440    // Same signedness; use the higher-ranked type
5441    destType = compare >= 0 ? lhs : rhs;
5442  } else if (compare != (lhsSigned ? 1 : -1)) {
5443    // The unsigned type has greater than or equal rank to the
5444    // signed type, so use the unsigned type
5445    destType = lhsSigned ? rhs : lhs;
5446  } else if (getIntWidth(lhs) != getIntWidth(rhs)) {
5447    // The two types are different widths; if we are here, that
5448    // means the signed type is larger than the unsigned type, so
5449    // use the signed type.
5450    destType = lhsSigned ? lhs : rhs;
5451  } else {
5452    // The signed type is higher-ranked than the unsigned type,
5453    // but isn't actually any bigger (like unsigned int and long
5454    // on most 32-bit systems).  Use the unsigned type corresponding
5455    // to the signed type.
5456    destType = getCorrespondingUnsignedType(lhsSigned ? lhs : rhs);
5457  }
5458  return destType;
5459}
5460
5461GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
5462  GVALinkage External = GVA_StrongExternal;
5463
5464  Linkage L = FD->getLinkage();
5465  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5466      FD->getType()->getLinkage() == UniqueExternalLinkage)
5467    L = UniqueExternalLinkage;
5468
5469  switch (L) {
5470  case NoLinkage:
5471  case InternalLinkage:
5472  case UniqueExternalLinkage:
5473    return GVA_Internal;
5474
5475  case ExternalLinkage:
5476    switch (FD->getTemplateSpecializationKind()) {
5477    case TSK_Undeclared:
5478    case TSK_ExplicitSpecialization:
5479      External = GVA_StrongExternal;
5480      break;
5481
5482    case TSK_ExplicitInstantiationDefinition:
5483      return GVA_ExplicitTemplateInstantiation;
5484
5485    case TSK_ExplicitInstantiationDeclaration:
5486    case TSK_ImplicitInstantiation:
5487      External = GVA_TemplateInstantiation;
5488      break;
5489    }
5490  }
5491
5492  if (!FD->isInlined())
5493    return External;
5494
5495  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
5496    // GNU or C99 inline semantics. Determine whether this symbol should be
5497    // externally visible.
5498    if (FD->isInlineDefinitionExternallyVisible())
5499      return External;
5500
5501    // C99 inline semantics, where the symbol is not externally visible.
5502    return GVA_C99Inline;
5503  }
5504
5505  // C++0x [temp.explicit]p9:
5506  //   [ Note: The intent is that an inline function that is the subject of
5507  //   an explicit instantiation declaration will still be implicitly
5508  //   instantiated when used so that the body can be considered for
5509  //   inlining, but that no out-of-line copy of the inline function would be
5510  //   generated in the translation unit. -- end note ]
5511  if (FD->getTemplateSpecializationKind()
5512                                       == TSK_ExplicitInstantiationDeclaration)
5513    return GVA_C99Inline;
5514
5515  return GVA_CXXInline;
5516}
5517
5518GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
5519  // If this is a static data member, compute the kind of template
5520  // specialization. Otherwise, this variable is not part of a
5521  // template.
5522  TemplateSpecializationKind TSK = TSK_Undeclared;
5523  if (VD->isStaticDataMember())
5524    TSK = VD->getTemplateSpecializationKind();
5525
5526  Linkage L = VD->getLinkage();
5527  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5528      VD->getType()->getLinkage() == UniqueExternalLinkage)
5529    L = UniqueExternalLinkage;
5530
5531  switch (L) {
5532  case NoLinkage:
5533  case InternalLinkage:
5534  case UniqueExternalLinkage:
5535    return GVA_Internal;
5536
5537  case ExternalLinkage:
5538    switch (TSK) {
5539    case TSK_Undeclared:
5540    case TSK_ExplicitSpecialization:
5541      return GVA_StrongExternal;
5542
5543    case TSK_ExplicitInstantiationDeclaration:
5544      llvm_unreachable("Variable should not be instantiated");
5545      // Fall through to treat this like any other instantiation.
5546
5547    case TSK_ExplicitInstantiationDefinition:
5548      return GVA_ExplicitTemplateInstantiation;
5549
5550    case TSK_ImplicitInstantiation:
5551      return GVA_TemplateInstantiation;
5552    }
5553  }
5554
5555  return GVA_StrongExternal;
5556}
5557
5558bool ASTContext::DeclMustBeEmitted(const Decl *D) {
5559  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
5560    if (!VD->isFileVarDecl())
5561      return false;
5562  } else if (!isa<FunctionDecl>(D))
5563    return false;
5564
5565  // Weak references don't produce any output by themselves.
5566  if (D->hasAttr<WeakRefAttr>())
5567    return false;
5568
5569  // Aliases and used decls are required.
5570  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
5571    return true;
5572
5573  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
5574    // Forward declarations aren't required.
5575    if (!FD->isThisDeclarationADefinition())
5576      return false;
5577
5578    // Constructors and destructors are required.
5579    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
5580      return true;
5581
5582    // The key function for a class is required.
5583    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
5584      const CXXRecordDecl *RD = MD->getParent();
5585      if (MD->isOutOfLine() && RD->isDynamicClass()) {
5586        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
5587        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
5588          return true;
5589      }
5590    }
5591
5592    GVALinkage Linkage = GetGVALinkageForFunction(FD);
5593
5594    // static, static inline, always_inline, and extern inline functions can
5595    // always be deferred.  Normal inline functions can be deferred in C99/C++.
5596    // Implicit template instantiations can also be deferred in C++.
5597    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
5598        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
5599      return false;
5600    return true;
5601  }
5602
5603  const VarDecl *VD = cast<VarDecl>(D);
5604  assert(VD->isFileVarDecl() && "Expected file scoped var");
5605
5606  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
5607    return false;
5608
5609  // Structs that have non-trivial constructors or destructors are required.
5610
5611  // FIXME: Handle references.
5612  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
5613    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
5614      if (RD->hasDefinition() &&
5615          (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()))
5616        return true;
5617    }
5618  }
5619
5620  GVALinkage L = GetGVALinkageForVariable(VD);
5621  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
5622    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
5623      return false;
5624  }
5625
5626  return true;
5627}
5628
5629CXXABI::~CXXABI() {}
5630