ASTContext.cpp revision 78a916ec5ff5b66adec3c499e1b9af7b87668309 
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  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
211                                                    AEnd = DeclAttrs.end();
212       A != AEnd; ++A)
213    A->second->~AttrVec();
214}
215
216void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
217  Deallocations.push_back(std::make_pair(Callback, Data));
218}
219
220void
221ASTContext::setExternalSource(llvm::OwningPtr<ExternalASTSource> &Source) {
222  ExternalSource.reset(Source.take());
223}
224
225void ASTContext::PrintStats() const {
226  fprintf(stderr, "*** AST Context Stats:\n");
227  fprintf(stderr, "  %d types total.\n", (int)Types.size());
228
229  unsigned counts[] = {
230#define TYPE(Name, Parent) 0,
231#define ABSTRACT_TYPE(Name, Parent)
232#include "clang/AST/TypeNodes.def"
233    0 // Extra
234  };
235
236  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
237    Type *T = Types[i];
238    counts[(unsigned)T->getTypeClass()]++;
239  }
240
241  unsigned Idx = 0;
242  unsigned TotalBytes = 0;
243#define TYPE(Name, Parent)                                              \
244  if (counts[Idx])                                                      \
245    fprintf(stderr, "    %d %s types\n", (int)counts[Idx], #Name);      \
246  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
247  ++Idx;
248#define ABSTRACT_TYPE(Name, Parent)
249#include "clang/AST/TypeNodes.def"
250
251  fprintf(stderr, "Total bytes = %d\n", int(TotalBytes));
252
253  // Implicit special member functions.
254  fprintf(stderr, "  %u/%u implicit default constructors created\n",
255          NumImplicitDefaultConstructorsDeclared,
256          NumImplicitDefaultConstructors);
257  fprintf(stderr, "  %u/%u implicit copy constructors created\n",
258          NumImplicitCopyConstructorsDeclared,
259          NumImplicitCopyConstructors);
260  fprintf(stderr, "  %u/%u implicit copy assignment operators created\n",
261          NumImplicitCopyAssignmentOperatorsDeclared,
262          NumImplicitCopyAssignmentOperators);
263  fprintf(stderr, "  %u/%u implicit destructors created\n",
264          NumImplicitDestructorsDeclared, NumImplicitDestructors);
265
266  if (ExternalSource.get()) {
267    fprintf(stderr, "\n");
268    ExternalSource->PrintStats();
269  }
270
271  BumpAlloc.PrintStats();
272}
273
274
275void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
276  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
277  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
278  Types.push_back(Ty);
279}
280
281void ASTContext::InitBuiltinTypes() {
282  assert(VoidTy.isNull() && "Context reinitialized?");
283
284  // C99 6.2.5p19.
285  InitBuiltinType(VoidTy,              BuiltinType::Void);
286
287  // C99 6.2.5p2.
288  InitBuiltinType(BoolTy,              BuiltinType::Bool);
289  // C99 6.2.5p3.
290  if (LangOpts.CharIsSigned)
291    InitBuiltinType(CharTy,            BuiltinType::Char_S);
292  else
293    InitBuiltinType(CharTy,            BuiltinType::Char_U);
294  // C99 6.2.5p4.
295  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
296  InitBuiltinType(ShortTy,             BuiltinType::Short);
297  InitBuiltinType(IntTy,               BuiltinType::Int);
298  InitBuiltinType(LongTy,              BuiltinType::Long);
299  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
300
301  // C99 6.2.5p6.
302  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
303  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
304  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
305  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
306  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
307
308  // C99 6.2.5p10.
309  InitBuiltinType(FloatTy,             BuiltinType::Float);
310  InitBuiltinType(DoubleTy,            BuiltinType::Double);
311  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
312
313  // GNU extension, 128-bit integers.
314  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
315  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
316
317  if (LangOpts.CPlusPlus) // C++ 3.9.1p5
318    InitBuiltinType(WCharTy,           BuiltinType::WChar);
319  else // C99
320    WCharTy = getFromTargetType(Target.getWCharType());
321
322  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
323    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
324  else // C99
325    Char16Ty = getFromTargetType(Target.getChar16Type());
326
327  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
328    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
329  else // C99
330    Char32Ty = getFromTargetType(Target.getChar32Type());
331
332  // Placeholder type for functions.
333  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
334
335  // Placeholder type for type-dependent expressions whose type is
336  // completely unknown. No code should ever check a type against
337  // DependentTy and users should never see it; however, it is here to
338  // help diagnose failures to properly check for type-dependent
339  // expressions.
340  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
341
342  // Placeholder type for C++0x auto declarations whose real type has
343  // not yet been deduced.
344  InitBuiltinType(UndeducedAutoTy, BuiltinType::UndeducedAuto);
345
346  // C99 6.2.5p11.
347  FloatComplexTy      = getComplexType(FloatTy);
348  DoubleComplexTy     = getComplexType(DoubleTy);
349  LongDoubleComplexTy = getComplexType(LongDoubleTy);
350
351  BuiltinVaListType = QualType();
352
353  // "Builtin" typedefs set by Sema::ActOnTranslationUnitScope().
354  ObjCIdTypedefType = QualType();
355  ObjCClassTypedefType = QualType();
356  ObjCSelTypedefType = QualType();
357
358  // Builtin types for 'id', 'Class', and 'SEL'.
359  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
360  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
361  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
362
363  ObjCConstantStringType = QualType();
364
365  // void * type
366  VoidPtrTy = getPointerType(VoidTy);
367
368  // nullptr type (C++0x 2.14.7)
369  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
370}
371
372Diagnostic &ASTContext::getDiagnostics() const {
373  return SourceMgr.getDiagnostics();
374}
375
376AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
377  AttrVec *&Result = DeclAttrs[D];
378  if (!Result) {
379    void *Mem = Allocate(sizeof(AttrVec));
380    Result = new (Mem) AttrVec;
381  }
382
383  return *Result;
384}
385
386/// \brief Erase the attributes corresponding to the given declaration.
387void ASTContext::eraseDeclAttrs(const Decl *D) {
388  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
389  if (Pos != DeclAttrs.end()) {
390    Pos->second->~AttrVec();
391    DeclAttrs.erase(Pos);
392  }
393}
394
395
396MemberSpecializationInfo *
397ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
398  assert(Var->isStaticDataMember() && "Not a static data member");
399  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
400    = InstantiatedFromStaticDataMember.find(Var);
401  if (Pos == InstantiatedFromStaticDataMember.end())
402    return 0;
403
404  return Pos->second;
405}
406
407void
408ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
409                                                TemplateSpecializationKind TSK,
410                                          SourceLocation PointOfInstantiation) {
411  assert(Inst->isStaticDataMember() && "Not a static data member");
412  assert(Tmpl->isStaticDataMember() && "Not a static data member");
413  assert(!InstantiatedFromStaticDataMember[Inst] &&
414         "Already noted what static data member was instantiated from");
415  InstantiatedFromStaticDataMember[Inst]
416    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
417}
418
419NamedDecl *
420ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
421  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
422    = InstantiatedFromUsingDecl.find(UUD);
423  if (Pos == InstantiatedFromUsingDecl.end())
424    return 0;
425
426  return Pos->second;
427}
428
429void
430ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
431  assert((isa<UsingDecl>(Pattern) ||
432          isa<UnresolvedUsingValueDecl>(Pattern) ||
433          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
434         "pattern decl is not a using decl");
435  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
436  InstantiatedFromUsingDecl[Inst] = Pattern;
437}
438
439UsingShadowDecl *
440ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
441  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
442    = InstantiatedFromUsingShadowDecl.find(Inst);
443  if (Pos == InstantiatedFromUsingShadowDecl.end())
444    return 0;
445
446  return Pos->second;
447}
448
449void
450ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
451                                               UsingShadowDecl *Pattern) {
452  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
453  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
454}
455
456FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
457  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
458    = InstantiatedFromUnnamedFieldDecl.find(Field);
459  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
460    return 0;
461
462  return Pos->second;
463}
464
465void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
466                                                     FieldDecl *Tmpl) {
467  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
468  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
469  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
470         "Already noted what unnamed field was instantiated from");
471
472  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
473}
474
475ASTContext::overridden_cxx_method_iterator
476ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
477  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
478    = OverriddenMethods.find(Method);
479  if (Pos == OverriddenMethods.end())
480    return 0;
481
482  return Pos->second.begin();
483}
484
485ASTContext::overridden_cxx_method_iterator
486ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
487  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
488    = OverriddenMethods.find(Method);
489  if (Pos == OverriddenMethods.end())
490    return 0;
491
492  return Pos->second.end();
493}
494
495unsigned
496ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
497  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
498    = OverriddenMethods.find(Method);
499  if (Pos == OverriddenMethods.end())
500    return 0;
501
502  return Pos->second.size();
503}
504
505void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
506                                     const CXXMethodDecl *Overridden) {
507  OverriddenMethods[Method].push_back(Overridden);
508}
509
510//===----------------------------------------------------------------------===//
511//                         Type Sizing and Analysis
512//===----------------------------------------------------------------------===//
513
514/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
515/// scalar floating point type.
516const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
517  const BuiltinType *BT = T->getAs<BuiltinType>();
518  assert(BT && "Not a floating point type!");
519  switch (BT->getKind()) {
520  default: assert(0 && "Not a floating point type!");
521  case BuiltinType::Float:      return Target.getFloatFormat();
522  case BuiltinType::Double:     return Target.getDoubleFormat();
523  case BuiltinType::LongDouble: return Target.getLongDoubleFormat();
524  }
525}
526
527/// getDeclAlign - Return a conservative estimate of the alignment of the
528/// specified decl.  Note that bitfields do not have a valid alignment, so
529/// this method will assert on them.
530/// If @p RefAsPointee, references are treated like their underlying type
531/// (for alignof), else they're treated like pointers (for CodeGen).
532CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) {
533  unsigned Align = Target.getCharWidth();
534
535  Align = std::max(Align, D->getMaxAlignment());
536
537  if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
538    QualType T = VD->getType();
539    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
540      if (RefAsPointee)
541        T = RT->getPointeeType();
542      else
543        T = getPointerType(RT->getPointeeType());
544    }
545    if (!T->isIncompleteType() && !T->isFunctionType()) {
546      unsigned MinWidth = Target.getLargeArrayMinWidth();
547      unsigned ArrayAlign = Target.getLargeArrayAlign();
548      if (isa<VariableArrayType>(T) && MinWidth != 0)
549        Align = std::max(Align, ArrayAlign);
550      if (ConstantArrayType *CT = dyn_cast<ConstantArrayType>(T)) {
551        unsigned Size = getTypeSize(CT);
552        if (MinWidth != 0 && MinWidth <= Size)
553          Align = std::max(Align, ArrayAlign);
554      }
555      // Incomplete or function types default to 1.
556      while (isa<VariableArrayType>(T) || isa<IncompleteArrayType>(T))
557        T = cast<ArrayType>(T)->getElementType();
558
559      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
560    }
561    if (const FieldDecl *FD = dyn_cast<FieldDecl>(VD)) {
562      // In the case of a field in a packed struct, we want the minimum
563      // of the alignment of the field and the alignment of the struct.
564      Align = std::min(Align,
565        getPreferredTypeAlign(FD->getParent()->getTypeForDecl()));
566    }
567  }
568
569  return CharUnits::fromQuantity(Align / Target.getCharWidth());
570}
571
572std::pair<CharUnits, CharUnits>
573ASTContext::getTypeInfoInChars(const Type *T) {
574  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
575  return std::make_pair(CharUnits::fromQuantity(Info.first / getCharWidth()),
576                        CharUnits::fromQuantity(Info.second / getCharWidth()));
577}
578
579std::pair<CharUnits, CharUnits>
580ASTContext::getTypeInfoInChars(QualType T) {
581  return getTypeInfoInChars(T.getTypePtr());
582}
583
584/// getTypeSize - Return the size of the specified type, in bits.  This method
585/// does not work on incomplete types.
586///
587/// FIXME: Pointers into different addr spaces could have different sizes and
588/// alignment requirements: getPointerInfo should take an AddrSpace, this
589/// should take a QualType, &c.
590std::pair<uint64_t, unsigned>
591ASTContext::getTypeInfo(const Type *T) {
592  uint64_t Width=0;
593  unsigned Align=8;
594  switch (T->getTypeClass()) {
595#define TYPE(Class, Base)
596#define ABSTRACT_TYPE(Class, Base)
597#define NON_CANONICAL_TYPE(Class, Base)
598#define DEPENDENT_TYPE(Class, Base) case Type::Class:
599#include "clang/AST/TypeNodes.def"
600    assert(false && "Should not see dependent types");
601    break;
602
603  case Type::FunctionNoProto:
604  case Type::FunctionProto:
605    // GCC extension: alignof(function) = 32 bits
606    Width = 0;
607    Align = 32;
608    break;
609
610  case Type::IncompleteArray:
611  case Type::VariableArray:
612    Width = 0;
613    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
614    break;
615
616  case Type::ConstantArray: {
617    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
618
619    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
620    Width = EltInfo.first*CAT->getSize().getZExtValue();
621    Align = EltInfo.second;
622    break;
623  }
624  case Type::ExtVector:
625  case Type::Vector: {
626    const VectorType *VT = cast<VectorType>(T);
627    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
628    Width = EltInfo.first*VT->getNumElements();
629    Align = Width;
630    // If the alignment is not a power of 2, round up to the next power of 2.
631    // This happens for non-power-of-2 length vectors.
632    if (Align & (Align-1)) {
633      Align = llvm::NextPowerOf2(Align);
634      Width = llvm::RoundUpToAlignment(Width, Align);
635    }
636    break;
637  }
638
639  case Type::Builtin:
640    switch (cast<BuiltinType>(T)->getKind()) {
641    default: assert(0 && "Unknown builtin type!");
642    case BuiltinType::Void:
643      // GCC extension: alignof(void) = 8 bits.
644      Width = 0;
645      Align = 8;
646      break;
647
648    case BuiltinType::Bool:
649      Width = Target.getBoolWidth();
650      Align = Target.getBoolAlign();
651      break;
652    case BuiltinType::Char_S:
653    case BuiltinType::Char_U:
654    case BuiltinType::UChar:
655    case BuiltinType::SChar:
656      Width = Target.getCharWidth();
657      Align = Target.getCharAlign();
658      break;
659    case BuiltinType::WChar:
660      Width = Target.getWCharWidth();
661      Align = Target.getWCharAlign();
662      break;
663    case BuiltinType::Char16:
664      Width = Target.getChar16Width();
665      Align = Target.getChar16Align();
666      break;
667    case BuiltinType::Char32:
668      Width = Target.getChar32Width();
669      Align = Target.getChar32Align();
670      break;
671    case BuiltinType::UShort:
672    case BuiltinType::Short:
673      Width = Target.getShortWidth();
674      Align = Target.getShortAlign();
675      break;
676    case BuiltinType::UInt:
677    case BuiltinType::Int:
678      Width = Target.getIntWidth();
679      Align = Target.getIntAlign();
680      break;
681    case BuiltinType::ULong:
682    case BuiltinType::Long:
683      Width = Target.getLongWidth();
684      Align = Target.getLongAlign();
685      break;
686    case BuiltinType::ULongLong:
687    case BuiltinType::LongLong:
688      Width = Target.getLongLongWidth();
689      Align = Target.getLongLongAlign();
690      break;
691    case BuiltinType::Int128:
692    case BuiltinType::UInt128:
693      Width = 128;
694      Align = 128; // int128_t is 128-bit aligned on all targets.
695      break;
696    case BuiltinType::Float:
697      Width = Target.getFloatWidth();
698      Align = Target.getFloatAlign();
699      break;
700    case BuiltinType::Double:
701      Width = Target.getDoubleWidth();
702      Align = Target.getDoubleAlign();
703      break;
704    case BuiltinType::LongDouble:
705      Width = Target.getLongDoubleWidth();
706      Align = Target.getLongDoubleAlign();
707      break;
708    case BuiltinType::NullPtr:
709      Width = Target.getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
710      Align = Target.getPointerAlign(0); //   == sizeof(void*)
711      break;
712    case BuiltinType::ObjCId:
713    case BuiltinType::ObjCClass:
714    case BuiltinType::ObjCSel:
715      Width = Target.getPointerWidth(0);
716      Align = Target.getPointerAlign(0);
717      break;
718    }
719    break;
720  case Type::ObjCObjectPointer:
721    Width = Target.getPointerWidth(0);
722    Align = Target.getPointerAlign(0);
723    break;
724  case Type::BlockPointer: {
725    unsigned AS = cast<BlockPointerType>(T)->getPointeeType().getAddressSpace();
726    Width = Target.getPointerWidth(AS);
727    Align = Target.getPointerAlign(AS);
728    break;
729  }
730  case Type::LValueReference:
731  case Type::RValueReference: {
732    // alignof and sizeof should never enter this code path here, so we go
733    // the pointer route.
734    unsigned AS = cast<ReferenceType>(T)->getPointeeType().getAddressSpace();
735    Width = Target.getPointerWidth(AS);
736    Align = Target.getPointerAlign(AS);
737    break;
738  }
739  case Type::Pointer: {
740    unsigned AS = cast<PointerType>(T)->getPointeeType().getAddressSpace();
741    Width = Target.getPointerWidth(AS);
742    Align = Target.getPointerAlign(AS);
743    break;
744  }
745  case Type::MemberPointer: {
746    const MemberPointerType *MPT = cast<MemberPointerType>(T);
747    std::pair<uint64_t, unsigned> PtrDiffInfo =
748      getTypeInfo(getPointerDiffType());
749    Width = PtrDiffInfo.first * ABI->getMemberPointerSize(MPT);
750    Align = PtrDiffInfo.second;
751    break;
752  }
753  case Type::Complex: {
754    // Complex types have the same alignment as their elements, but twice the
755    // size.
756    std::pair<uint64_t, unsigned> EltInfo =
757      getTypeInfo(cast<ComplexType>(T)->getElementType());
758    Width = EltInfo.first*2;
759    Align = EltInfo.second;
760    break;
761  }
762  case Type::ObjCObject:
763    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
764  case Type::ObjCInterface: {
765    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
766    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
767    Width = Layout.getSize();
768    Align = Layout.getAlignment();
769    break;
770  }
771  case Type::Record:
772  case Type::Enum: {
773    const TagType *TT = cast<TagType>(T);
774
775    if (TT->getDecl()->isInvalidDecl()) {
776      Width = 1;
777      Align = 1;
778      break;
779    }
780
781    if (const EnumType *ET = dyn_cast<EnumType>(TT))
782      return getTypeInfo(ET->getDecl()->getIntegerType());
783
784    const RecordType *RT = cast<RecordType>(TT);
785    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
786    Width = Layout.getSize();
787    Align = Layout.getAlignment();
788    break;
789  }
790
791  case Type::SubstTemplateTypeParm:
792    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
793                       getReplacementType().getTypePtr());
794
795  case Type::Typedef: {
796    const TypedefDecl *Typedef = cast<TypedefType>(T)->getDecl();
797    std::pair<uint64_t, unsigned> Info
798      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
799    Align = std::max(Typedef->getMaxAlignment(), Info.second);
800    Width = Info.first;
801    break;
802  }
803
804  case Type::TypeOfExpr:
805    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
806                         .getTypePtr());
807
808  case Type::TypeOf:
809    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
810
811  case Type::Decltype:
812    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
813                        .getTypePtr());
814
815  case Type::Elaborated:
816    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
817
818  case Type::TemplateSpecialization:
819    assert(getCanonicalType(T) != T &&
820           "Cannot request the size of a dependent type");
821    // FIXME: this is likely to be wrong once we support template
822    // aliases, since a template alias could refer to a typedef that
823    // has an __aligned__ attribute on it.
824    return getTypeInfo(getCanonicalType(T));
825  }
826
827  assert(Align && (Align & (Align-1)) == 0 && "Alignment must be power of 2");
828  return std::make_pair(Width, Align);
829}
830
831/// getTypeSizeInChars - Return the size of the specified type, in characters.
832/// This method does not work on incomplete types.
833CharUnits ASTContext::getTypeSizeInChars(QualType T) {
834  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
835}
836CharUnits ASTContext::getTypeSizeInChars(const Type *T) {
837  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
838}
839
840/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
841/// characters. This method does not work on incomplete types.
842CharUnits ASTContext::getTypeAlignInChars(QualType T) {
843  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
844}
845CharUnits ASTContext::getTypeAlignInChars(const Type *T) {
846  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
847}
848
849/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
850/// type for the current target in bits.  This can be different than the ABI
851/// alignment in cases where it is beneficial for performance to overalign
852/// a data type.
853unsigned ASTContext::getPreferredTypeAlign(const Type *T) {
854  unsigned ABIAlign = getTypeAlign(T);
855
856  // Double and long long should be naturally aligned if possible.
857  if (const ComplexType* CT = T->getAs<ComplexType>())
858    T = CT->getElementType().getTypePtr();
859  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
860      T->isSpecificBuiltinType(BuiltinType::LongLong))
861    return std::max(ABIAlign, (unsigned)getTypeSize(T));
862
863  return ABIAlign;
864}
865
866/// ShallowCollectObjCIvars -
867/// Collect all ivars, including those synthesized, in the current class.
868///
869void ASTContext::ShallowCollectObjCIvars(const ObjCInterfaceDecl *OI,
870                                 llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
871  // FIXME. This need be removed but there are two many places which
872  // assume const-ness of ObjCInterfaceDecl
873  ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
874  for (ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
875        Iv= Iv->getNextIvar())
876    Ivars.push_back(Iv);
877}
878
879/// DeepCollectObjCIvars -
880/// This routine first collects all declared, but not synthesized, ivars in
881/// super class and then collects all ivars, including those synthesized for
882/// current class. This routine is used for implementation of current class
883/// when all ivars, declared and synthesized are known.
884///
885void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
886                                      bool leafClass,
887                                llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
888  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
889    DeepCollectObjCIvars(SuperClass, false, Ivars);
890  if (!leafClass) {
891    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
892         E = OI->ivar_end(); I != E; ++I)
893      Ivars.push_back(*I);
894  }
895  else
896    ShallowCollectObjCIvars(OI, Ivars);
897}
898
899/// CollectInheritedProtocols - Collect all protocols in current class and
900/// those inherited by it.
901void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
902                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
903  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
904    // We can use protocol_iterator here instead of
905    // all_referenced_protocol_iterator since we are walking all categories.
906    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
907         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
908      ObjCProtocolDecl *Proto = (*P);
909      Protocols.insert(Proto);
910      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
911           PE = Proto->protocol_end(); P != PE; ++P) {
912        Protocols.insert(*P);
913        CollectInheritedProtocols(*P, Protocols);
914      }
915    }
916
917    // Categories of this Interface.
918    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
919         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
920      CollectInheritedProtocols(CDeclChain, Protocols);
921    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
922      while (SD) {
923        CollectInheritedProtocols(SD, Protocols);
924        SD = SD->getSuperClass();
925      }
926  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
927    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
928         PE = OC->protocol_end(); P != PE; ++P) {
929      ObjCProtocolDecl *Proto = (*P);
930      Protocols.insert(Proto);
931      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
932           PE = Proto->protocol_end(); P != PE; ++P)
933        CollectInheritedProtocols(*P, Protocols);
934    }
935  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
936    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
937         PE = OP->protocol_end(); P != PE; ++P) {
938      ObjCProtocolDecl *Proto = (*P);
939      Protocols.insert(Proto);
940      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
941           PE = Proto->protocol_end(); P != PE; ++P)
942        CollectInheritedProtocols(*P, Protocols);
943    }
944  }
945}
946
947unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) {
948  unsigned count = 0;
949  // Count ivars declared in class extension.
950  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
951       CDecl = CDecl->getNextClassExtension())
952    count += CDecl->ivar_size();
953
954  // Count ivar defined in this class's implementation.  This
955  // includes synthesized ivars.
956  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
957    count += ImplDecl->ivar_size();
958
959  return count;
960}
961
962/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
963ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
964  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
965    I = ObjCImpls.find(D);
966  if (I != ObjCImpls.end())
967    return cast<ObjCImplementationDecl>(I->second);
968  return 0;
969}
970/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
971ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
972  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
973    I = ObjCImpls.find(D);
974  if (I != ObjCImpls.end())
975    return cast<ObjCCategoryImplDecl>(I->second);
976  return 0;
977}
978
979/// \brief Set the implementation of ObjCInterfaceDecl.
980void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
981                           ObjCImplementationDecl *ImplD) {
982  assert(IFaceD && ImplD && "Passed null params");
983  ObjCImpls[IFaceD] = ImplD;
984}
985/// \brief Set the implementation of ObjCCategoryDecl.
986void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
987                           ObjCCategoryImplDecl *ImplD) {
988  assert(CatD && ImplD && "Passed null params");
989  ObjCImpls[CatD] = ImplD;
990}
991
992/// \brief Allocate an uninitialized TypeSourceInfo.
993///
994/// The caller should initialize the memory held by TypeSourceInfo using
995/// the TypeLoc wrappers.
996///
997/// \param T the type that will be the basis for type source info. This type
998/// should refer to how the declarator was written in source code, not to
999/// what type semantic analysis resolved the declarator to.
1000TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1001                                                 unsigned DataSize) {
1002  if (!DataSize)
1003    DataSize = TypeLoc::getFullDataSizeForType(T);
1004  else
1005    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1006           "incorrect data size provided to CreateTypeSourceInfo!");
1007
1008  TypeSourceInfo *TInfo =
1009    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1010  new (TInfo) TypeSourceInfo(T);
1011  return TInfo;
1012}
1013
1014TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1015                                                     SourceLocation L) {
1016  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1017  DI->getTypeLoc().initialize(L);
1018  return DI;
1019}
1020
1021const ASTRecordLayout &
1022ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) {
1023  return getObjCLayout(D, 0);
1024}
1025
1026const ASTRecordLayout &
1027ASTContext::getASTObjCImplementationLayout(const ObjCImplementationDecl *D) {
1028  return getObjCLayout(D->getClassInterface(), D);
1029}
1030
1031//===----------------------------------------------------------------------===//
1032//                   Type creation/memoization methods
1033//===----------------------------------------------------------------------===//
1034
1035QualType ASTContext::getExtQualType(const Type *TypeNode, Qualifiers Quals) {
1036  unsigned Fast = Quals.getFastQualifiers();
1037  Quals.removeFastQualifiers();
1038
1039  // Check if we've already instantiated this type.
1040  llvm::FoldingSetNodeID ID;
1041  ExtQuals::Profile(ID, TypeNode, Quals);
1042  void *InsertPos = 0;
1043  if (ExtQuals *EQ = ExtQualNodes.FindNodeOrInsertPos(ID, InsertPos)) {
1044    assert(EQ->getQualifiers() == Quals);
1045    QualType T = QualType(EQ, Fast);
1046    return T;
1047  }
1048
1049  ExtQuals *New = new (*this, TypeAlignment) ExtQuals(*this, TypeNode, Quals);
1050  ExtQualNodes.InsertNode(New, InsertPos);
1051  QualType T = QualType(New, Fast);
1052  return T;
1053}
1054
1055QualType ASTContext::getVolatileType(QualType T) {
1056  QualType CanT = getCanonicalType(T);
1057  if (CanT.isVolatileQualified()) return T;
1058
1059  QualifierCollector Quals;
1060  const Type *TypeNode = Quals.strip(T);
1061  Quals.addVolatile();
1062
1063  return getExtQualType(TypeNode, Quals);
1064}
1065
1066QualType ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) {
1067  QualType CanT = getCanonicalType(T);
1068  if (CanT.getAddressSpace() == AddressSpace)
1069    return T;
1070
1071  // If we are composing extended qualifiers together, merge together
1072  // into one ExtQuals node.
1073  QualifierCollector Quals;
1074  const Type *TypeNode = Quals.strip(T);
1075
1076  // If this type already has an address space specified, it cannot get
1077  // another one.
1078  assert(!Quals.hasAddressSpace() &&
1079         "Type cannot be in multiple addr spaces!");
1080  Quals.addAddressSpace(AddressSpace);
1081
1082  return getExtQualType(TypeNode, Quals);
1083}
1084
1085QualType ASTContext::getObjCGCQualType(QualType T,
1086                                       Qualifiers::GC GCAttr) {
1087  QualType CanT = getCanonicalType(T);
1088  if (CanT.getObjCGCAttr() == GCAttr)
1089    return T;
1090
1091  if (T->isPointerType()) {
1092    QualType Pointee = T->getAs<PointerType>()->getPointeeType();
1093    if (Pointee->isAnyPointerType()) {
1094      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1095      return getPointerType(ResultType);
1096    }
1097  }
1098
1099  // If we are composing extended qualifiers together, merge together
1100  // into one ExtQuals node.
1101  QualifierCollector Quals;
1102  const Type *TypeNode = Quals.strip(T);
1103
1104  // If this type already has an ObjCGC specified, it cannot get
1105  // another one.
1106  assert(!Quals.hasObjCGCAttr() &&
1107         "Type cannot have multiple ObjCGCs!");
1108  Quals.addObjCGCAttr(GCAttr);
1109
1110  return getExtQualType(TypeNode, Quals);
1111}
1112
1113static QualType getExtFunctionType(ASTContext& Context, QualType T,
1114                                        const FunctionType::ExtInfo &Info) {
1115  QualType ResultType;
1116  if (const PointerType *Pointer = T->getAs<PointerType>()) {
1117    QualType Pointee = Pointer->getPointeeType();
1118    ResultType = getExtFunctionType(Context, Pointee, Info);
1119    if (ResultType == Pointee)
1120      return T;
1121
1122    ResultType = Context.getPointerType(ResultType);
1123  } else if (const BlockPointerType *BlockPointer
1124                                              = T->getAs<BlockPointerType>()) {
1125    QualType Pointee = BlockPointer->getPointeeType();
1126    ResultType = getExtFunctionType(Context, Pointee, Info);
1127    if (ResultType == Pointee)
1128      return T;
1129
1130    ResultType = Context.getBlockPointerType(ResultType);
1131  } else if (const MemberPointerType *MemberPointer
1132                                            = T->getAs<MemberPointerType>()) {
1133    QualType Pointee = MemberPointer->getPointeeType();
1134    ResultType = getExtFunctionType(Context, Pointee, Info);
1135    if (ResultType == Pointee)
1136      return T;
1137
1138    ResultType = Context.getMemberPointerType(ResultType,
1139                                              MemberPointer->getClass());
1140   } else if (const FunctionType *F = T->getAs<FunctionType>()) {
1141    if (F->getExtInfo() == Info)
1142      return T;
1143
1144    if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(F)) {
1145      ResultType = Context.getFunctionNoProtoType(FNPT->getResultType(),
1146                                                  Info);
1147    } else {
1148      const FunctionProtoType *FPT = cast<FunctionProtoType>(F);
1149      ResultType
1150        = Context.getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1151                                  FPT->getNumArgs(), FPT->isVariadic(),
1152                                  FPT->getTypeQuals(),
1153                                  FPT->hasExceptionSpec(),
1154                                  FPT->hasAnyExceptionSpec(),
1155                                  FPT->getNumExceptions(),
1156                                  FPT->exception_begin(),
1157                                  Info);
1158    }
1159  } else
1160    return T;
1161
1162  return Context.getQualifiedType(ResultType, T.getLocalQualifiers());
1163}
1164
1165QualType ASTContext::getNoReturnType(QualType T, bool AddNoReturn) {
1166  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1167  return getExtFunctionType(*this, T,
1168                                 Info.withNoReturn(AddNoReturn));
1169}
1170
1171QualType ASTContext::getCallConvType(QualType T, CallingConv CallConv) {
1172  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1173  return getExtFunctionType(*this, T,
1174                            Info.withCallingConv(CallConv));
1175}
1176
1177QualType ASTContext::getRegParmType(QualType T, unsigned RegParm) {
1178  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1179  return getExtFunctionType(*this, T,
1180                                 Info.withRegParm(RegParm));
1181}
1182
1183/// getComplexType - Return the uniqued reference to the type for a complex
1184/// number with the specified element type.
1185QualType ASTContext::getComplexType(QualType T) {
1186  // Unique pointers, to guarantee there is only one pointer of a particular
1187  // structure.
1188  llvm::FoldingSetNodeID ID;
1189  ComplexType::Profile(ID, T);
1190
1191  void *InsertPos = 0;
1192  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1193    return QualType(CT, 0);
1194
1195  // If the pointee type isn't canonical, this won't be a canonical type either,
1196  // so fill in the canonical type field.
1197  QualType Canonical;
1198  if (!T.isCanonical()) {
1199    Canonical = getComplexType(getCanonicalType(T));
1200
1201    // Get the new insert position for the node we care about.
1202    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1203    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1204  }
1205  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1206  Types.push_back(New);
1207  ComplexTypes.InsertNode(New, InsertPos);
1208  return QualType(New, 0);
1209}
1210
1211/// getPointerType - Return the uniqued reference to the type for a pointer to
1212/// the specified type.
1213QualType ASTContext::getPointerType(QualType T) {
1214  // Unique pointers, to guarantee there is only one pointer of a particular
1215  // structure.
1216  llvm::FoldingSetNodeID ID;
1217  PointerType::Profile(ID, T);
1218
1219  void *InsertPos = 0;
1220  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1221    return QualType(PT, 0);
1222
1223  // If the pointee type isn't canonical, this won't be a canonical type either,
1224  // so fill in the canonical type field.
1225  QualType Canonical;
1226  if (!T.isCanonical()) {
1227    Canonical = getPointerType(getCanonicalType(T));
1228
1229    // Get the new insert position for the node we care about.
1230    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1231    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1232  }
1233  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1234  Types.push_back(New);
1235  PointerTypes.InsertNode(New, InsertPos);
1236  return QualType(New, 0);
1237}
1238
1239/// getBlockPointerType - Return the uniqued reference to the type for
1240/// a pointer to the specified block.
1241QualType ASTContext::getBlockPointerType(QualType T) {
1242  assert(T->isFunctionType() && "block of function types only");
1243  // Unique pointers, to guarantee there is only one block of a particular
1244  // structure.
1245  llvm::FoldingSetNodeID ID;
1246  BlockPointerType::Profile(ID, T);
1247
1248  void *InsertPos = 0;
1249  if (BlockPointerType *PT =
1250        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1251    return QualType(PT, 0);
1252
1253  // If the block pointee type isn't canonical, this won't be a canonical
1254  // type either so fill in the canonical type field.
1255  QualType Canonical;
1256  if (!T.isCanonical()) {
1257    Canonical = getBlockPointerType(getCanonicalType(T));
1258
1259    // Get the new insert position for the node we care about.
1260    BlockPointerType *NewIP =
1261      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1262    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1263  }
1264  BlockPointerType *New
1265    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1266  Types.push_back(New);
1267  BlockPointerTypes.InsertNode(New, InsertPos);
1268  return QualType(New, 0);
1269}
1270
1271/// getLValueReferenceType - Return the uniqued reference to the type for an
1272/// lvalue reference to the specified type.
1273QualType ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) {
1274  // Unique pointers, to guarantee there is only one pointer of a particular
1275  // structure.
1276  llvm::FoldingSetNodeID ID;
1277  ReferenceType::Profile(ID, T, SpelledAsLValue);
1278
1279  void *InsertPos = 0;
1280  if (LValueReferenceType *RT =
1281        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1282    return QualType(RT, 0);
1283
1284  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1285
1286  // If the referencee type isn't canonical, this won't be a canonical type
1287  // either, so fill in the canonical type field.
1288  QualType Canonical;
1289  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1290    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1291    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1292
1293    // Get the new insert position for the node we care about.
1294    LValueReferenceType *NewIP =
1295      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1296    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1297  }
1298
1299  LValueReferenceType *New
1300    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1301                                                     SpelledAsLValue);
1302  Types.push_back(New);
1303  LValueReferenceTypes.InsertNode(New, InsertPos);
1304
1305  return QualType(New, 0);
1306}
1307
1308/// getRValueReferenceType - Return the uniqued reference to the type for an
1309/// rvalue reference to the specified type.
1310QualType ASTContext::getRValueReferenceType(QualType T) {
1311  // Unique pointers, to guarantee there is only one pointer of a particular
1312  // structure.
1313  llvm::FoldingSetNodeID ID;
1314  ReferenceType::Profile(ID, T, false);
1315
1316  void *InsertPos = 0;
1317  if (RValueReferenceType *RT =
1318        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1319    return QualType(RT, 0);
1320
1321  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1322
1323  // If the referencee type isn't canonical, this won't be a canonical type
1324  // either, so fill in the canonical type field.
1325  QualType Canonical;
1326  if (InnerRef || !T.isCanonical()) {
1327    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1328    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1329
1330    // Get the new insert position for the node we care about.
1331    RValueReferenceType *NewIP =
1332      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1333    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1334  }
1335
1336  RValueReferenceType *New
1337    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1338  Types.push_back(New);
1339  RValueReferenceTypes.InsertNode(New, InsertPos);
1340  return QualType(New, 0);
1341}
1342
1343/// getMemberPointerType - Return the uniqued reference to the type for a
1344/// member pointer to the specified type, in the specified class.
1345QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) {
1346  // Unique pointers, to guarantee there is only one pointer of a particular
1347  // structure.
1348  llvm::FoldingSetNodeID ID;
1349  MemberPointerType::Profile(ID, T, Cls);
1350
1351  void *InsertPos = 0;
1352  if (MemberPointerType *PT =
1353      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1354    return QualType(PT, 0);
1355
1356  // If the pointee or class type isn't canonical, this won't be a canonical
1357  // type either, so fill in the canonical type field.
1358  QualType Canonical;
1359  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1360    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1361
1362    // Get the new insert position for the node we care about.
1363    MemberPointerType *NewIP =
1364      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1365    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1366  }
1367  MemberPointerType *New
1368    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1369  Types.push_back(New);
1370  MemberPointerTypes.InsertNode(New, InsertPos);
1371  return QualType(New, 0);
1372}
1373
1374/// getConstantArrayType - Return the unique reference to the type for an
1375/// array of the specified element type.
1376QualType ASTContext::getConstantArrayType(QualType EltTy,
1377                                          const llvm::APInt &ArySizeIn,
1378                                          ArrayType::ArraySizeModifier ASM,
1379                                          unsigned EltTypeQuals) {
1380  assert((EltTy->isDependentType() ||
1381          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1382         "Constant array of VLAs is illegal!");
1383
1384  // Convert the array size into a canonical width matching the pointer size for
1385  // the target.
1386  llvm::APInt ArySize(ArySizeIn);
1387  ArySize.zextOrTrunc(Target.getPointerWidth(EltTy.getAddressSpace()));
1388
1389  llvm::FoldingSetNodeID ID;
1390  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, EltTypeQuals);
1391
1392  void *InsertPos = 0;
1393  if (ConstantArrayType *ATP =
1394      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1395    return QualType(ATP, 0);
1396
1397  // If the element type isn't canonical, this won't be a canonical type either,
1398  // so fill in the canonical type field.
1399  QualType Canonical;
1400  if (!EltTy.isCanonical()) {
1401    Canonical = getConstantArrayType(getCanonicalType(EltTy), ArySize,
1402                                     ASM, EltTypeQuals);
1403    // Get the new insert position for the node we care about.
1404    ConstantArrayType *NewIP =
1405      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1406    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1407  }
1408
1409  ConstantArrayType *New = new(*this,TypeAlignment)
1410    ConstantArrayType(EltTy, Canonical, ArySize, ASM, EltTypeQuals);
1411  ConstantArrayTypes.InsertNode(New, InsertPos);
1412  Types.push_back(New);
1413  return QualType(New, 0);
1414}
1415
1416/// getVariableArrayType - Returns a non-unique reference to the type for a
1417/// variable array of the specified element type.
1418QualType ASTContext::getVariableArrayType(QualType EltTy,
1419                                          Expr *NumElts,
1420                                          ArrayType::ArraySizeModifier ASM,
1421                                          unsigned EltTypeQuals,
1422                                          SourceRange Brackets) {
1423  // Since we don't unique expressions, it isn't possible to unique VLA's
1424  // that have an expression provided for their size.
1425  QualType CanonType;
1426
1427  if (!EltTy.isCanonical()) {
1428    if (NumElts)
1429      NumElts->Retain();
1430    CanonType = getVariableArrayType(getCanonicalType(EltTy), NumElts, ASM,
1431                                     EltTypeQuals, Brackets);
1432  }
1433
1434  VariableArrayType *New = new(*this, TypeAlignment)
1435    VariableArrayType(EltTy, CanonType, NumElts, ASM, EltTypeQuals, Brackets);
1436
1437  VariableArrayTypes.push_back(New);
1438  Types.push_back(New);
1439  return QualType(New, 0);
1440}
1441
1442/// getDependentSizedArrayType - Returns a non-unique reference to
1443/// the type for a dependently-sized array of the specified element
1444/// type.
1445QualType ASTContext::getDependentSizedArrayType(QualType EltTy,
1446                                                Expr *NumElts,
1447                                                ArrayType::ArraySizeModifier ASM,
1448                                                unsigned EltTypeQuals,
1449                                                SourceRange Brackets) {
1450  assert((!NumElts || NumElts->isTypeDependent() ||
1451          NumElts->isValueDependent()) &&
1452         "Size must be type- or value-dependent!");
1453
1454  void *InsertPos = 0;
1455  DependentSizedArrayType *Canon = 0;
1456  llvm::FoldingSetNodeID ID;
1457
1458  if (NumElts) {
1459    // Dependently-sized array types that do not have a specified
1460    // number of elements will have their sizes deduced from an
1461    // initializer.
1462    DependentSizedArrayType::Profile(ID, *this, getCanonicalType(EltTy), ASM,
1463                                     EltTypeQuals, NumElts);
1464
1465    Canon = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1466  }
1467
1468  DependentSizedArrayType *New;
1469  if (Canon) {
1470    // We already have a canonical version of this array type; use it as
1471    // the canonical type for a newly-built type.
1472    New = new (*this, TypeAlignment)
1473      DependentSizedArrayType(*this, EltTy, QualType(Canon, 0),
1474                              NumElts, ASM, EltTypeQuals, Brackets);
1475  } else {
1476    QualType CanonEltTy = getCanonicalType(EltTy);
1477    if (CanonEltTy == EltTy) {
1478      New = new (*this, TypeAlignment)
1479        DependentSizedArrayType(*this, EltTy, QualType(),
1480                                NumElts, ASM, EltTypeQuals, Brackets);
1481
1482      if (NumElts) {
1483        DependentSizedArrayType *CanonCheck
1484          = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1485        assert(!CanonCheck && "Dependent-sized canonical array type broken");
1486        (void)CanonCheck;
1487        DependentSizedArrayTypes.InsertNode(New, InsertPos);
1488      }
1489    } else {
1490      QualType Canon = getDependentSizedArrayType(CanonEltTy, NumElts,
1491                                                  ASM, EltTypeQuals,
1492                                                  SourceRange());
1493      New = new (*this, TypeAlignment)
1494        DependentSizedArrayType(*this, EltTy, Canon,
1495                                NumElts, ASM, EltTypeQuals, Brackets);
1496    }
1497  }
1498
1499  Types.push_back(New);
1500  return QualType(New, 0);
1501}
1502
1503QualType ASTContext::getIncompleteArrayType(QualType EltTy,
1504                                            ArrayType::ArraySizeModifier ASM,
1505                                            unsigned EltTypeQuals) {
1506  llvm::FoldingSetNodeID ID;
1507  IncompleteArrayType::Profile(ID, EltTy, ASM, EltTypeQuals);
1508
1509  void *InsertPos = 0;
1510  if (IncompleteArrayType *ATP =
1511       IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1512    return QualType(ATP, 0);
1513
1514  // If the element type isn't canonical, this won't be a canonical type
1515  // either, so fill in the canonical type field.
1516  QualType Canonical;
1517
1518  if (!EltTy.isCanonical()) {
1519    Canonical = getIncompleteArrayType(getCanonicalType(EltTy),
1520                                       ASM, EltTypeQuals);
1521
1522    // Get the new insert position for the node we care about.
1523    IncompleteArrayType *NewIP =
1524      IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1525    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1526  }
1527
1528  IncompleteArrayType *New = new (*this, TypeAlignment)
1529    IncompleteArrayType(EltTy, Canonical, ASM, EltTypeQuals);
1530
1531  IncompleteArrayTypes.InsertNode(New, InsertPos);
1532  Types.push_back(New);
1533  return QualType(New, 0);
1534}
1535
1536/// getVectorType - Return the unique reference to a vector type of
1537/// the specified element type and size. VectorType must be a built-in type.
1538QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1539    VectorType::AltiVecSpecific AltiVecSpec) {
1540  BuiltinType *baseType;
1541
1542  baseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1543  assert(baseType != 0 && "getVectorType(): Expecting a built-in type");
1544
1545  // Check if we've already instantiated a vector of this type.
1546  llvm::FoldingSetNodeID ID;
1547  VectorType::Profile(ID, vecType, NumElts, Type::Vector, AltiVecSpec);
1548
1549  void *InsertPos = 0;
1550  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1551    return QualType(VTP, 0);
1552
1553  // If the element type isn't canonical, this won't be a canonical type either,
1554  // so fill in the canonical type field.
1555  QualType Canonical;
1556  if (!vecType.isCanonical()) {
1557    Canonical = getVectorType(getCanonicalType(vecType), NumElts,
1558      VectorType::NotAltiVec);
1559
1560    // Get the new insert position for the node we care about.
1561    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1562    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1563  }
1564  VectorType *New = new (*this, TypeAlignment)
1565    VectorType(vecType, NumElts, Canonical, AltiVecSpec);
1566  VectorTypes.InsertNode(New, InsertPos);
1567  Types.push_back(New);
1568  return QualType(New, 0);
1569}
1570
1571/// getExtVectorType - Return the unique reference to an extended vector type of
1572/// the specified element type and size. VectorType must be a built-in type.
1573QualType ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) {
1574  BuiltinType *baseType;
1575
1576  baseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1577  assert(baseType != 0 && "getExtVectorType(): Expecting a built-in type");
1578
1579  // Check if we've already instantiated a vector of this type.
1580  llvm::FoldingSetNodeID ID;
1581  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1582                      VectorType::NotAltiVec);
1583  void *InsertPos = 0;
1584  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1585    return QualType(VTP, 0);
1586
1587  // If the element type isn't canonical, this won't be a canonical type either,
1588  // so fill in the canonical type field.
1589  QualType Canonical;
1590  if (!vecType.isCanonical()) {
1591    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
1592
1593    // Get the new insert position for the node we care about.
1594    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1595    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1596  }
1597  ExtVectorType *New = new (*this, TypeAlignment)
1598    ExtVectorType(vecType, NumElts, Canonical);
1599  VectorTypes.InsertNode(New, InsertPos);
1600  Types.push_back(New);
1601  return QualType(New, 0);
1602}
1603
1604QualType ASTContext::getDependentSizedExtVectorType(QualType vecType,
1605                                                    Expr *SizeExpr,
1606                                                    SourceLocation AttrLoc) {
1607  llvm::FoldingSetNodeID ID;
1608  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
1609                                       SizeExpr);
1610
1611  void *InsertPos = 0;
1612  DependentSizedExtVectorType *Canon
1613    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1614  DependentSizedExtVectorType *New;
1615  if (Canon) {
1616    // We already have a canonical version of this array type; use it as
1617    // the canonical type for a newly-built type.
1618    New = new (*this, TypeAlignment)
1619      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
1620                                  SizeExpr, AttrLoc);
1621  } else {
1622    QualType CanonVecTy = getCanonicalType(vecType);
1623    if (CanonVecTy == vecType) {
1624      New = new (*this, TypeAlignment)
1625        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
1626                                    AttrLoc);
1627
1628      DependentSizedExtVectorType *CanonCheck
1629        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1630      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
1631      (void)CanonCheck;
1632      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
1633    } else {
1634      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
1635                                                      SourceLocation());
1636      New = new (*this, TypeAlignment)
1637        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
1638    }
1639  }
1640
1641  Types.push_back(New);
1642  return QualType(New, 0);
1643}
1644
1645/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
1646///
1647QualType ASTContext::getFunctionNoProtoType(QualType ResultTy,
1648                                            const FunctionType::ExtInfo &Info) {
1649  const CallingConv CallConv = Info.getCC();
1650  // Unique functions, to guarantee there is only one function of a particular
1651  // structure.
1652  llvm::FoldingSetNodeID ID;
1653  FunctionNoProtoType::Profile(ID, ResultTy, Info);
1654
1655  void *InsertPos = 0;
1656  if (FunctionNoProtoType *FT =
1657        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1658    return QualType(FT, 0);
1659
1660  QualType Canonical;
1661  if (!ResultTy.isCanonical() ||
1662      getCanonicalCallConv(CallConv) != CallConv) {
1663    Canonical =
1664      getFunctionNoProtoType(getCanonicalType(ResultTy),
1665                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1666
1667    // Get the new insert position for the node we care about.
1668    FunctionNoProtoType *NewIP =
1669      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1670    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1671  }
1672
1673  FunctionNoProtoType *New = new (*this, TypeAlignment)
1674    FunctionNoProtoType(ResultTy, Canonical, Info);
1675  Types.push_back(New);
1676  FunctionNoProtoTypes.InsertNode(New, InsertPos);
1677  return QualType(New, 0);
1678}
1679
1680/// getFunctionType - Return a normal function type with a typed argument
1681/// list.  isVariadic indicates whether the argument list includes '...'.
1682QualType ASTContext::getFunctionType(QualType ResultTy,const QualType *ArgArray,
1683                                     unsigned NumArgs, bool isVariadic,
1684                                     unsigned TypeQuals, bool hasExceptionSpec,
1685                                     bool hasAnyExceptionSpec, unsigned NumExs,
1686                                     const QualType *ExArray,
1687                                     const FunctionType::ExtInfo &Info) {
1688  const CallingConv CallConv= Info.getCC();
1689  // Unique functions, to guarantee there is only one function of a particular
1690  // structure.
1691  llvm::FoldingSetNodeID ID;
1692  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, isVariadic,
1693                             TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1694                             NumExs, ExArray, Info);
1695
1696  void *InsertPos = 0;
1697  if (FunctionProtoType *FTP =
1698        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1699    return QualType(FTP, 0);
1700
1701  // Determine whether the type being created is already canonical or not.
1702  bool isCanonical = !hasExceptionSpec && ResultTy.isCanonical();
1703  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
1704    if (!ArgArray[i].isCanonicalAsParam())
1705      isCanonical = false;
1706
1707  // If this type isn't canonical, get the canonical version of it.
1708  // The exception spec is not part of the canonical type.
1709  QualType Canonical;
1710  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
1711    llvm::SmallVector<QualType, 16> CanonicalArgs;
1712    CanonicalArgs.reserve(NumArgs);
1713    for (unsigned i = 0; i != NumArgs; ++i)
1714      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
1715
1716    Canonical = getFunctionType(getCanonicalType(ResultTy),
1717                                CanonicalArgs.data(), NumArgs,
1718                                isVariadic, TypeQuals, false,
1719                                false, 0, 0,
1720                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1721
1722    // Get the new insert position for the node we care about.
1723    FunctionProtoType *NewIP =
1724      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1725    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1726  }
1727
1728  // FunctionProtoType objects are allocated with extra bytes after them
1729  // for two variable size arrays (for parameter and exception types) at the
1730  // end of them.
1731  FunctionProtoType *FTP =
1732    (FunctionProtoType*)Allocate(sizeof(FunctionProtoType) +
1733                                 NumArgs*sizeof(QualType) +
1734                                 NumExs*sizeof(QualType), TypeAlignment);
1735  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, isVariadic,
1736                              TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1737                              ExArray, NumExs, Canonical, Info);
1738  Types.push_back(FTP);
1739  FunctionProtoTypes.InsertNode(FTP, InsertPos);
1740  return QualType(FTP, 0);
1741}
1742
1743#ifndef NDEBUG
1744static bool NeedsInjectedClassNameType(const RecordDecl *D) {
1745  if (!isa<CXXRecordDecl>(D)) return false;
1746  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
1747  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
1748    return true;
1749  if (RD->getDescribedClassTemplate() &&
1750      !isa<ClassTemplateSpecializationDecl>(RD))
1751    return true;
1752  return false;
1753}
1754#endif
1755
1756/// getInjectedClassNameType - Return the unique reference to the
1757/// injected class name type for the specified templated declaration.
1758QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
1759                                              QualType TST) {
1760  assert(NeedsInjectedClassNameType(Decl));
1761  if (Decl->TypeForDecl) {
1762    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1763  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDeclaration()) {
1764    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
1765    Decl->TypeForDecl = PrevDecl->TypeForDecl;
1766    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1767  } else {
1768    Decl->TypeForDecl =
1769      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
1770    Types.push_back(Decl->TypeForDecl);
1771  }
1772  return QualType(Decl->TypeForDecl, 0);
1773}
1774
1775/// getTypeDeclType - Return the unique reference to the type for the
1776/// specified type declaration.
1777QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) {
1778  assert(Decl && "Passed null for Decl param");
1779  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
1780
1781  if (const TypedefDecl *Typedef = dyn_cast<TypedefDecl>(Decl))
1782    return getTypedefType(Typedef);
1783
1784  assert(!isa<TemplateTypeParmDecl>(Decl) &&
1785         "Template type parameter types are always available.");
1786
1787  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
1788    assert(!Record->getPreviousDeclaration() &&
1789           "struct/union has previous declaration");
1790    assert(!NeedsInjectedClassNameType(Record));
1791    return getRecordType(Record);
1792  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
1793    assert(!Enum->getPreviousDeclaration() &&
1794           "enum has previous declaration");
1795    return getEnumType(Enum);
1796  } else if (const UnresolvedUsingTypenameDecl *Using =
1797               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
1798    Decl->TypeForDecl = new (*this, TypeAlignment) UnresolvedUsingType(Using);
1799  } else
1800    llvm_unreachable("TypeDecl without a type?");
1801
1802  Types.push_back(Decl->TypeForDecl);
1803  return QualType(Decl->TypeForDecl, 0);
1804}
1805
1806/// getTypedefType - Return the unique reference to the type for the
1807/// specified typename decl.
1808QualType
1809ASTContext::getTypedefType(const TypedefDecl *Decl, QualType Canonical) {
1810  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1811
1812  if (Canonical.isNull())
1813    Canonical = getCanonicalType(Decl->getUnderlyingType());
1814  Decl->TypeForDecl = new(*this, TypeAlignment)
1815    TypedefType(Type::Typedef, Decl, Canonical);
1816  Types.push_back(Decl->TypeForDecl);
1817  return QualType(Decl->TypeForDecl, 0);
1818}
1819
1820QualType ASTContext::getRecordType(const RecordDecl *Decl) {
1821  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1822
1823  if (const RecordDecl *PrevDecl = Decl->getPreviousDeclaration())
1824    if (PrevDecl->TypeForDecl)
1825      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1826
1827  Decl->TypeForDecl = new (*this, TypeAlignment) RecordType(Decl);
1828  Types.push_back(Decl->TypeForDecl);
1829  return QualType(Decl->TypeForDecl, 0);
1830}
1831
1832QualType ASTContext::getEnumType(const EnumDecl *Decl) {
1833  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1834
1835  if (const EnumDecl *PrevDecl = Decl->getPreviousDeclaration())
1836    if (PrevDecl->TypeForDecl)
1837      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1838
1839  Decl->TypeForDecl = new (*this, TypeAlignment) EnumType(Decl);
1840  Types.push_back(Decl->TypeForDecl);
1841  return QualType(Decl->TypeForDecl, 0);
1842}
1843
1844/// \brief Retrieve a substitution-result type.
1845QualType
1846ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
1847                                         QualType Replacement) {
1848  assert(Replacement.isCanonical()
1849         && "replacement types must always be canonical");
1850
1851  llvm::FoldingSetNodeID ID;
1852  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
1853  void *InsertPos = 0;
1854  SubstTemplateTypeParmType *SubstParm
1855    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1856
1857  if (!SubstParm) {
1858    SubstParm = new (*this, TypeAlignment)
1859      SubstTemplateTypeParmType(Parm, Replacement);
1860    Types.push_back(SubstParm);
1861    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
1862  }
1863
1864  return QualType(SubstParm, 0);
1865}
1866
1867/// \brief Retrieve the template type parameter type for a template
1868/// parameter or parameter pack with the given depth, index, and (optionally)
1869/// name.
1870QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
1871                                             bool ParameterPack,
1872                                             IdentifierInfo *Name) {
1873  llvm::FoldingSetNodeID ID;
1874  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, Name);
1875  void *InsertPos = 0;
1876  TemplateTypeParmType *TypeParm
1877    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1878
1879  if (TypeParm)
1880    return QualType(TypeParm, 0);
1881
1882  if (Name) {
1883    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
1884    TypeParm = new (*this, TypeAlignment)
1885      TemplateTypeParmType(Depth, Index, ParameterPack, Name, Canon);
1886
1887    TemplateTypeParmType *TypeCheck
1888      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1889    assert(!TypeCheck && "Template type parameter canonical type broken");
1890    (void)TypeCheck;
1891  } else
1892    TypeParm = new (*this, TypeAlignment)
1893      TemplateTypeParmType(Depth, Index, ParameterPack);
1894
1895  Types.push_back(TypeParm);
1896  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
1897
1898  return QualType(TypeParm, 0);
1899}
1900
1901TypeSourceInfo *
1902ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
1903                                              SourceLocation NameLoc,
1904                                        const TemplateArgumentListInfo &Args,
1905                                              QualType CanonType) {
1906  QualType TST = getTemplateSpecializationType(Name, Args, CanonType);
1907
1908  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
1909  TemplateSpecializationTypeLoc TL
1910    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
1911  TL.setTemplateNameLoc(NameLoc);
1912  TL.setLAngleLoc(Args.getLAngleLoc());
1913  TL.setRAngleLoc(Args.getRAngleLoc());
1914  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
1915    TL.setArgLocInfo(i, Args[i].getLocInfo());
1916  return DI;
1917}
1918
1919QualType
1920ASTContext::getTemplateSpecializationType(TemplateName Template,
1921                                          const TemplateArgumentListInfo &Args,
1922                                          QualType Canon) {
1923  unsigned NumArgs = Args.size();
1924
1925  llvm::SmallVector<TemplateArgument, 4> ArgVec;
1926  ArgVec.reserve(NumArgs);
1927  for (unsigned i = 0; i != NumArgs; ++i)
1928    ArgVec.push_back(Args[i].getArgument());
1929
1930  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
1931                                       Canon);
1932}
1933
1934QualType
1935ASTContext::getTemplateSpecializationType(TemplateName Template,
1936                                          const TemplateArgument *Args,
1937                                          unsigned NumArgs,
1938                                          QualType Canon) {
1939  if (!Canon.isNull())
1940    Canon = getCanonicalType(Canon);
1941  else
1942    Canon = getCanonicalTemplateSpecializationType(Template, Args, NumArgs);
1943
1944  // Allocate the (non-canonical) template specialization type, but don't
1945  // try to unique it: these types typically have location information that
1946  // we don't unique and don't want to lose.
1947  void *Mem = Allocate((sizeof(TemplateSpecializationType) +
1948                        sizeof(TemplateArgument) * NumArgs),
1949                       TypeAlignment);
1950  TemplateSpecializationType *Spec
1951    = new (Mem) TemplateSpecializationType(Template,
1952                                           Args, NumArgs,
1953                                           Canon);
1954
1955  Types.push_back(Spec);
1956  return QualType(Spec, 0);
1957}
1958
1959QualType
1960ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
1961                                                   const TemplateArgument *Args,
1962                                                   unsigned NumArgs) {
1963  // Build the canonical template specialization type.
1964  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
1965  llvm::SmallVector<TemplateArgument, 4> CanonArgs;
1966  CanonArgs.reserve(NumArgs);
1967  for (unsigned I = 0; I != NumArgs; ++I)
1968    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
1969
1970  // Determine whether this canonical template specialization type already
1971  // exists.
1972  llvm::FoldingSetNodeID ID;
1973  TemplateSpecializationType::Profile(ID, CanonTemplate,
1974                                      CanonArgs.data(), NumArgs, *this);
1975
1976  void *InsertPos = 0;
1977  TemplateSpecializationType *Spec
1978    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
1979
1980  if (!Spec) {
1981    // Allocate a new canonical template specialization type.
1982    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
1983                          sizeof(TemplateArgument) * NumArgs),
1984                         TypeAlignment);
1985    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
1986                                                CanonArgs.data(), NumArgs,
1987                                                QualType());
1988    Types.push_back(Spec);
1989    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
1990  }
1991
1992  assert(Spec->isDependentType() &&
1993         "Non-dependent template-id type must have a canonical type");
1994  return QualType(Spec, 0);
1995}
1996
1997QualType
1998ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
1999                              NestedNameSpecifier *NNS,
2000                              QualType NamedType) {
2001  llvm::FoldingSetNodeID ID;
2002  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2003
2004  void *InsertPos = 0;
2005  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2006  if (T)
2007    return QualType(T, 0);
2008
2009  QualType Canon = NamedType;
2010  if (!Canon.isCanonical()) {
2011    Canon = getCanonicalType(NamedType);
2012    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2013    assert(!CheckT && "Elaborated canonical type broken");
2014    (void)CheckT;
2015  }
2016
2017  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2018  Types.push_back(T);
2019  ElaboratedTypes.InsertNode(T, InsertPos);
2020  return QualType(T, 0);
2021}
2022
2023QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2024                                          NestedNameSpecifier *NNS,
2025                                          const IdentifierInfo *Name,
2026                                          QualType Canon) {
2027  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2028
2029  if (Canon.isNull()) {
2030    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2031    ElaboratedTypeKeyword CanonKeyword = Keyword;
2032    if (Keyword == ETK_None)
2033      CanonKeyword = ETK_Typename;
2034
2035    if (CanonNNS != NNS || CanonKeyword != Keyword)
2036      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2037  }
2038
2039  llvm::FoldingSetNodeID ID;
2040  DependentNameType::Profile(ID, Keyword, NNS, Name);
2041
2042  void *InsertPos = 0;
2043  DependentNameType *T
2044    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2045  if (T)
2046    return QualType(T, 0);
2047
2048  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2049  Types.push_back(T);
2050  DependentNameTypes.InsertNode(T, InsertPos);
2051  return QualType(T, 0);
2052}
2053
2054QualType
2055ASTContext::getDependentTemplateSpecializationType(
2056                                 ElaboratedTypeKeyword Keyword,
2057                                 NestedNameSpecifier *NNS,
2058                                 const IdentifierInfo *Name,
2059                                 const TemplateArgumentListInfo &Args) {
2060  // TODO: avoid this copy
2061  llvm::SmallVector<TemplateArgument, 16> ArgCopy;
2062  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2063    ArgCopy.push_back(Args[I].getArgument());
2064  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2065                                                ArgCopy.size(),
2066                                                ArgCopy.data());
2067}
2068
2069QualType
2070ASTContext::getDependentTemplateSpecializationType(
2071                                 ElaboratedTypeKeyword Keyword,
2072                                 NestedNameSpecifier *NNS,
2073                                 const IdentifierInfo *Name,
2074                                 unsigned NumArgs,
2075                                 const TemplateArgument *Args) {
2076  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2077
2078  llvm::FoldingSetNodeID ID;
2079  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2080                                               Name, NumArgs, Args);
2081
2082  void *InsertPos = 0;
2083  DependentTemplateSpecializationType *T
2084    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2085  if (T)
2086    return QualType(T, 0);
2087
2088  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2089
2090  ElaboratedTypeKeyword CanonKeyword = Keyword;
2091  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2092
2093  bool AnyNonCanonArgs = false;
2094  llvm::SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2095  for (unsigned I = 0; I != NumArgs; ++I) {
2096    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2097    if (!CanonArgs[I].structurallyEquals(Args[I]))
2098      AnyNonCanonArgs = true;
2099  }
2100
2101  QualType Canon;
2102  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2103    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2104                                                   Name, NumArgs,
2105                                                   CanonArgs.data());
2106
2107    // Find the insert position again.
2108    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2109  }
2110
2111  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2112                        sizeof(TemplateArgument) * NumArgs),
2113                       TypeAlignment);
2114  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2115                                                    Name, NumArgs, Args, Canon);
2116  Types.push_back(T);
2117  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2118  return QualType(T, 0);
2119}
2120
2121/// CmpProtocolNames - Comparison predicate for sorting protocols
2122/// alphabetically.
2123static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2124                            const ObjCProtocolDecl *RHS) {
2125  return LHS->getDeclName() < RHS->getDeclName();
2126}
2127
2128static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2129                                unsigned NumProtocols) {
2130  if (NumProtocols == 0) return true;
2131
2132  for (unsigned i = 1; i != NumProtocols; ++i)
2133    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]))
2134      return false;
2135  return true;
2136}
2137
2138static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2139                                   unsigned &NumProtocols) {
2140  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2141
2142  // Sort protocols, keyed by name.
2143  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2144
2145  // Remove duplicates.
2146  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2147  NumProtocols = ProtocolsEnd-Protocols;
2148}
2149
2150QualType ASTContext::getObjCObjectType(QualType BaseType,
2151                                       ObjCProtocolDecl * const *Protocols,
2152                                       unsigned NumProtocols) {
2153  // If the base type is an interface and there aren't any protocols
2154  // to add, then the interface type will do just fine.
2155  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2156    return BaseType;
2157
2158  // Look in the folding set for an existing type.
2159  llvm::FoldingSetNodeID ID;
2160  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2161  void *InsertPos = 0;
2162  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2163    return QualType(QT, 0);
2164
2165  // Build the canonical type, which has the canonical base type and
2166  // a sorted-and-uniqued list of protocols.
2167  QualType Canonical;
2168  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2169  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2170    if (!ProtocolsSorted) {
2171      llvm::SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2172                                                     Protocols + NumProtocols);
2173      unsigned UniqueCount = NumProtocols;
2174
2175      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2176      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2177                                    &Sorted[0], UniqueCount);
2178    } else {
2179      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2180                                    Protocols, NumProtocols);
2181    }
2182
2183    // Regenerate InsertPos.
2184    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2185  }
2186
2187  unsigned Size = sizeof(ObjCObjectTypeImpl);
2188  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2189  void *Mem = Allocate(Size, TypeAlignment);
2190  ObjCObjectTypeImpl *T =
2191    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2192
2193  Types.push_back(T);
2194  ObjCObjectTypes.InsertNode(T, InsertPos);
2195  return QualType(T, 0);
2196}
2197
2198/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2199/// the given object type.
2200QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) {
2201  llvm::FoldingSetNodeID ID;
2202  ObjCObjectPointerType::Profile(ID, ObjectT);
2203
2204  void *InsertPos = 0;
2205  if (ObjCObjectPointerType *QT =
2206              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2207    return QualType(QT, 0);
2208
2209  // Find the canonical object type.
2210  QualType Canonical;
2211  if (!ObjectT.isCanonical()) {
2212    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2213
2214    // Regenerate InsertPos.
2215    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2216  }
2217
2218  // No match.
2219  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2220  ObjCObjectPointerType *QType =
2221    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2222
2223  Types.push_back(QType);
2224  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2225  return QualType(QType, 0);
2226}
2227
2228/// getObjCInterfaceType - Return the unique reference to the type for the
2229/// specified ObjC interface decl. The list of protocols is optional.
2230QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl) {
2231  if (Decl->TypeForDecl)
2232    return QualType(Decl->TypeForDecl, 0);
2233
2234  // FIXME: redeclarations?
2235  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2236  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2237  Decl->TypeForDecl = T;
2238  Types.push_back(T);
2239  return QualType(T, 0);
2240}
2241
2242/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2243/// TypeOfExprType AST's (since expression's are never shared). For example,
2244/// multiple declarations that refer to "typeof(x)" all contain different
2245/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2246/// on canonical type's (which are always unique).
2247QualType ASTContext::getTypeOfExprType(Expr *tofExpr) {
2248  TypeOfExprType *toe;
2249  if (tofExpr->isTypeDependent()) {
2250    llvm::FoldingSetNodeID ID;
2251    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2252
2253    void *InsertPos = 0;
2254    DependentTypeOfExprType *Canon
2255      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2256    if (Canon) {
2257      // We already have a "canonical" version of an identical, dependent
2258      // typeof(expr) type. Use that as our canonical type.
2259      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2260                                          QualType((TypeOfExprType*)Canon, 0));
2261    }
2262    else {
2263      // Build a new, canonical typeof(expr) type.
2264      Canon
2265        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2266      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2267      toe = Canon;
2268    }
2269  } else {
2270    QualType Canonical = getCanonicalType(tofExpr->getType());
2271    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2272  }
2273  Types.push_back(toe);
2274  return QualType(toe, 0);
2275}
2276
2277/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2278/// TypeOfType AST's. The only motivation to unique these nodes would be
2279/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2280/// an issue. This doesn't effect the type checker, since it operates
2281/// on canonical type's (which are always unique).
2282QualType ASTContext::getTypeOfType(QualType tofType) {
2283  QualType Canonical = getCanonicalType(tofType);
2284  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2285  Types.push_back(tot);
2286  return QualType(tot, 0);
2287}
2288
2289/// getDecltypeForExpr - Given an expr, will return the decltype for that
2290/// expression, according to the rules in C++0x [dcl.type.simple]p4
2291static QualType getDecltypeForExpr(const Expr *e, ASTContext &Context) {
2292  if (e->isTypeDependent())
2293    return Context.DependentTy;
2294
2295  // If e is an id expression or a class member access, decltype(e) is defined
2296  // as the type of the entity named by e.
2297  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2298    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2299      return VD->getType();
2300  }
2301  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2302    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2303      return FD->getType();
2304  }
2305  // If e is a function call or an invocation of an overloaded operator,
2306  // (parentheses around e are ignored), decltype(e) is defined as the
2307  // return type of that function.
2308  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2309    return CE->getCallReturnType();
2310
2311  QualType T = e->getType();
2312
2313  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2314  // defined as T&, otherwise decltype(e) is defined as T.
2315  if (e->isLvalue(Context) == Expr::LV_Valid)
2316    T = Context.getLValueReferenceType(T);
2317
2318  return T;
2319}
2320
2321/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2322/// DecltypeType AST's. The only motivation to unique these nodes would be
2323/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2324/// an issue. This doesn't effect the type checker, since it operates
2325/// on canonical type's (which are always unique).
2326QualType ASTContext::getDecltypeType(Expr *e) {
2327  DecltypeType *dt;
2328  if (e->isTypeDependent()) {
2329    llvm::FoldingSetNodeID ID;
2330    DependentDecltypeType::Profile(ID, *this, e);
2331
2332    void *InsertPos = 0;
2333    DependentDecltypeType *Canon
2334      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2335    if (Canon) {
2336      // We already have a "canonical" version of an equivalent, dependent
2337      // decltype type. Use that as our canonical type.
2338      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2339                                       QualType((DecltypeType*)Canon, 0));
2340    }
2341    else {
2342      // Build a new, canonical typeof(expr) type.
2343      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2344      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2345      dt = Canon;
2346    }
2347  } else {
2348    QualType T = getDecltypeForExpr(e, *this);
2349    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2350  }
2351  Types.push_back(dt);
2352  return QualType(dt, 0);
2353}
2354
2355/// getTagDeclType - Return the unique reference to the type for the
2356/// specified TagDecl (struct/union/class/enum) decl.
2357QualType ASTContext::getTagDeclType(const TagDecl *Decl) {
2358  assert (Decl);
2359  // FIXME: What is the design on getTagDeclType when it requires casting
2360  // away const?  mutable?
2361  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2362}
2363
2364/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2365/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2366/// needs to agree with the definition in <stddef.h>.
2367CanQualType ASTContext::getSizeType() const {
2368  return getFromTargetType(Target.getSizeType());
2369}
2370
2371/// getSignedWCharType - Return the type of "signed wchar_t".
2372/// Used when in C++, as a GCC extension.
2373QualType ASTContext::getSignedWCharType() const {
2374  // FIXME: derive from "Target" ?
2375  return WCharTy;
2376}
2377
2378/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
2379/// Used when in C++, as a GCC extension.
2380QualType ASTContext::getUnsignedWCharType() const {
2381  // FIXME: derive from "Target" ?
2382  return UnsignedIntTy;
2383}
2384
2385/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
2386/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
2387QualType ASTContext::getPointerDiffType() const {
2388  return getFromTargetType(Target.getPtrDiffType(0));
2389}
2390
2391//===----------------------------------------------------------------------===//
2392//                              Type Operators
2393//===----------------------------------------------------------------------===//
2394
2395CanQualType ASTContext::getCanonicalParamType(QualType T) {
2396  // Push qualifiers into arrays, and then discard any remaining
2397  // qualifiers.
2398  T = getCanonicalType(T);
2399  const Type *Ty = T.getTypePtr();
2400
2401  QualType Result;
2402  if (isa<ArrayType>(Ty)) {
2403    Result = getArrayDecayedType(QualType(Ty,0));
2404  } else if (isa<FunctionType>(Ty)) {
2405    Result = getPointerType(QualType(Ty, 0));
2406  } else {
2407    Result = QualType(Ty, 0);
2408  }
2409
2410  return CanQualType::CreateUnsafe(Result);
2411}
2412
2413/// getCanonicalType - Return the canonical (structural) type corresponding to
2414/// the specified potentially non-canonical type.  The non-canonical version
2415/// of a type may have many "decorated" versions of types.  Decorators can
2416/// include typedefs, 'typeof' operators, etc. The returned type is guaranteed
2417/// to be free of any of these, allowing two canonical types to be compared
2418/// for exact equality with a simple pointer comparison.
2419CanQualType ASTContext::getCanonicalType(QualType T) {
2420  QualifierCollector Quals;
2421  const Type *Ptr = Quals.strip(T);
2422  QualType CanType = Ptr->getCanonicalTypeInternal();
2423
2424  // The canonical internal type will be the canonical type *except*
2425  // that we push type qualifiers down through array types.
2426
2427  // If there are no new qualifiers to push down, stop here.
2428  if (!Quals.hasQualifiers())
2429    return CanQualType::CreateUnsafe(CanType);
2430
2431  // If the type qualifiers are on an array type, get the canonical
2432  // type of the array with the qualifiers applied to the element
2433  // type.
2434  ArrayType *AT = dyn_cast<ArrayType>(CanType);
2435  if (!AT)
2436    return CanQualType::CreateUnsafe(getQualifiedType(CanType, Quals));
2437
2438  // Get the canonical version of the element with the extra qualifiers on it.
2439  // This can recursively sink qualifiers through multiple levels of arrays.
2440  QualType NewEltTy = getQualifiedType(AT->getElementType(), Quals);
2441  NewEltTy = getCanonicalType(NewEltTy);
2442
2443  if (ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
2444    return CanQualType::CreateUnsafe(
2445             getConstantArrayType(NewEltTy, CAT->getSize(),
2446                                  CAT->getSizeModifier(),
2447                                  CAT->getIndexTypeCVRQualifiers()));
2448  if (IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT))
2449    return CanQualType::CreateUnsafe(
2450             getIncompleteArrayType(NewEltTy, IAT->getSizeModifier(),
2451                                    IAT->getIndexTypeCVRQualifiers()));
2452
2453  if (DependentSizedArrayType *DSAT = dyn_cast<DependentSizedArrayType>(AT))
2454    return CanQualType::CreateUnsafe(
2455             getDependentSizedArrayType(NewEltTy,
2456                                        DSAT->getSizeExpr() ?
2457                                          DSAT->getSizeExpr()->Retain() : 0,
2458                                        DSAT->getSizeModifier(),
2459                                        DSAT->getIndexTypeCVRQualifiers(),
2460                        DSAT->getBracketsRange())->getCanonicalTypeInternal());
2461
2462  VariableArrayType *VAT = cast<VariableArrayType>(AT);
2463  return CanQualType::CreateUnsafe(getVariableArrayType(NewEltTy,
2464                                                        VAT->getSizeExpr() ?
2465                                              VAT->getSizeExpr()->Retain() : 0,
2466                                                        VAT->getSizeModifier(),
2467                                              VAT->getIndexTypeCVRQualifiers(),
2468                                                     VAT->getBracketsRange()));
2469}
2470
2471QualType ASTContext::getUnqualifiedArrayType(QualType T,
2472                                             Qualifiers &Quals) {
2473  Quals = T.getQualifiers();
2474  const ArrayType *AT = getAsArrayType(T);
2475  if (!AT) {
2476    return T.getUnqualifiedType();
2477  }
2478
2479  QualType Elt = AT->getElementType();
2480  QualType UnqualElt = getUnqualifiedArrayType(Elt, Quals);
2481  if (Elt == UnqualElt)
2482    return T;
2483
2484  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
2485    return getConstantArrayType(UnqualElt, CAT->getSize(),
2486                                CAT->getSizeModifier(), 0);
2487  }
2488
2489  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
2490    return getIncompleteArrayType(UnqualElt, IAT->getSizeModifier(), 0);
2491  }
2492
2493  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
2494    return getVariableArrayType(UnqualElt,
2495                                VAT->getSizeExpr() ?
2496                                VAT->getSizeExpr()->Retain() : 0,
2497                                VAT->getSizeModifier(),
2498                                VAT->getIndexTypeCVRQualifiers(),
2499                                VAT->getBracketsRange());
2500  }
2501
2502  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
2503  return getDependentSizedArrayType(UnqualElt, DSAT->getSizeExpr()->Retain(),
2504                                    DSAT->getSizeModifier(), 0,
2505                                    SourceRange());
2506}
2507
2508/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
2509/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
2510/// they point to and return true. If T1 and T2 aren't pointer types
2511/// or pointer-to-member types, or if they are not similar at this
2512/// level, returns false and leaves T1 and T2 unchanged. Top-level
2513/// qualifiers on T1 and T2 are ignored. This function will typically
2514/// be called in a loop that successively "unwraps" pointer and
2515/// pointer-to-member types to compare them at each level.
2516bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
2517  const PointerType *T1PtrType = T1->getAs<PointerType>(),
2518                    *T2PtrType = T2->getAs<PointerType>();
2519  if (T1PtrType && T2PtrType) {
2520    T1 = T1PtrType->getPointeeType();
2521    T2 = T2PtrType->getPointeeType();
2522    return true;
2523  }
2524
2525  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
2526                          *T2MPType = T2->getAs<MemberPointerType>();
2527  if (T1MPType && T2MPType &&
2528      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
2529                             QualType(T2MPType->getClass(), 0))) {
2530    T1 = T1MPType->getPointeeType();
2531    T2 = T2MPType->getPointeeType();
2532    return true;
2533  }
2534
2535  if (getLangOptions().ObjC1) {
2536    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
2537                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
2538    if (T1OPType && T2OPType) {
2539      T1 = T1OPType->getPointeeType();
2540      T2 = T2OPType->getPointeeType();
2541      return true;
2542    }
2543  }
2544
2545  // FIXME: Block pointers, too?
2546
2547  return false;
2548}
2549
2550DeclarationNameInfo ASTContext::getNameForTemplate(TemplateName Name,
2551                                                   SourceLocation NameLoc) {
2552  if (TemplateDecl *TD = Name.getAsTemplateDecl())
2553    // DNInfo work in progress: CHECKME: what about DNLoc?
2554    return DeclarationNameInfo(TD->getDeclName(), NameLoc);
2555
2556  if (DependentTemplateName *DTN = Name.getAsDependentTemplateName()) {
2557    DeclarationName DName;
2558    if (DTN->isIdentifier()) {
2559      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
2560      return DeclarationNameInfo(DName, NameLoc);
2561    } else {
2562      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
2563      // DNInfo work in progress: FIXME: source locations?
2564      DeclarationNameLoc DNLoc;
2565      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
2566      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
2567      return DeclarationNameInfo(DName, NameLoc, DNLoc);
2568    }
2569  }
2570
2571  OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
2572  assert(Storage);
2573  // DNInfo work in progress: CHECKME: what about DNLoc?
2574  return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
2575}
2576
2577TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) {
2578  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
2579    if (TemplateTemplateParmDecl *TTP
2580                              = dyn_cast<TemplateTemplateParmDecl>(Template))
2581      Template = getCanonicalTemplateTemplateParmDecl(TTP);
2582
2583    // The canonical template name is the canonical template declaration.
2584    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
2585  }
2586
2587  assert(!Name.getAsOverloadedTemplate());
2588
2589  DependentTemplateName *DTN = Name.getAsDependentTemplateName();
2590  assert(DTN && "Non-dependent template names must refer to template decls.");
2591  return DTN->CanonicalTemplateName;
2592}
2593
2594bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
2595  X = getCanonicalTemplateName(X);
2596  Y = getCanonicalTemplateName(Y);
2597  return X.getAsVoidPointer() == Y.getAsVoidPointer();
2598}
2599
2600TemplateArgument
2601ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) {
2602  switch (Arg.getKind()) {
2603    case TemplateArgument::Null:
2604      return Arg;
2605
2606    case TemplateArgument::Expression:
2607      return Arg;
2608
2609    case TemplateArgument::Declaration:
2610      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
2611
2612    case TemplateArgument::Template:
2613      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
2614
2615    case TemplateArgument::Integral:
2616      return TemplateArgument(*Arg.getAsIntegral(),
2617                              getCanonicalType(Arg.getIntegralType()));
2618
2619    case TemplateArgument::Type:
2620      return TemplateArgument(getCanonicalType(Arg.getAsType()));
2621
2622    case TemplateArgument::Pack: {
2623      // FIXME: Allocate in ASTContext
2624      TemplateArgument *CanonArgs = new TemplateArgument[Arg.pack_size()];
2625      unsigned Idx = 0;
2626      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
2627                                        AEnd = Arg.pack_end();
2628           A != AEnd; (void)++A, ++Idx)
2629        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
2630
2631      TemplateArgument Result;
2632      Result.setArgumentPack(CanonArgs, Arg.pack_size(), false);
2633      return Result;
2634    }
2635  }
2636
2637  // Silence GCC warning
2638  assert(false && "Unhandled template argument kind");
2639  return TemplateArgument();
2640}
2641
2642NestedNameSpecifier *
2643ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) {
2644  if (!NNS)
2645    return 0;
2646
2647  switch (NNS->getKind()) {
2648  case NestedNameSpecifier::Identifier:
2649    // Canonicalize the prefix but keep the identifier the same.
2650    return NestedNameSpecifier::Create(*this,
2651                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
2652                                       NNS->getAsIdentifier());
2653
2654  case NestedNameSpecifier::Namespace:
2655    // A namespace is canonical; build a nested-name-specifier with
2656    // this namespace and no prefix.
2657    return NestedNameSpecifier::Create(*this, 0, NNS->getAsNamespace());
2658
2659  case NestedNameSpecifier::TypeSpec:
2660  case NestedNameSpecifier::TypeSpecWithTemplate: {
2661    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
2662    return NestedNameSpecifier::Create(*this, 0,
2663                 NNS->getKind() == NestedNameSpecifier::TypeSpecWithTemplate,
2664                                       T.getTypePtr());
2665  }
2666
2667  case NestedNameSpecifier::Global:
2668    // The global specifier is canonical and unique.
2669    return NNS;
2670  }
2671
2672  // Required to silence a GCC warning
2673  return 0;
2674}
2675
2676
2677const ArrayType *ASTContext::getAsArrayType(QualType T) {
2678  // Handle the non-qualified case efficiently.
2679  if (!T.hasLocalQualifiers()) {
2680    // Handle the common positive case fast.
2681    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
2682      return AT;
2683  }
2684
2685  // Handle the common negative case fast.
2686  QualType CType = T->getCanonicalTypeInternal();
2687  if (!isa<ArrayType>(CType))
2688    return 0;
2689
2690  // Apply any qualifiers from the array type to the element type.  This
2691  // implements C99 6.7.3p8: "If the specification of an array type includes
2692  // any type qualifiers, the element type is so qualified, not the array type."
2693
2694  // If we get here, we either have type qualifiers on the type, or we have
2695  // sugar such as a typedef in the way.  If we have type qualifiers on the type
2696  // we must propagate them down into the element type.
2697
2698  QualifierCollector Qs;
2699  const Type *Ty = Qs.strip(T.getDesugaredType());
2700
2701  // If we have a simple case, just return now.
2702  const ArrayType *ATy = dyn_cast<ArrayType>(Ty);
2703  if (ATy == 0 || Qs.empty())
2704    return ATy;
2705
2706  // Otherwise, we have an array and we have qualifiers on it.  Push the
2707  // qualifiers into the array element type and return a new array type.
2708  // Get the canonical version of the element with the extra qualifiers on it.
2709  // This can recursively sink qualifiers through multiple levels of arrays.
2710  QualType NewEltTy = getQualifiedType(ATy->getElementType(), Qs);
2711
2712  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
2713    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
2714                                                CAT->getSizeModifier(),
2715                                           CAT->getIndexTypeCVRQualifiers()));
2716  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
2717    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
2718                                                  IAT->getSizeModifier(),
2719                                           IAT->getIndexTypeCVRQualifiers()));
2720
2721  if (const DependentSizedArrayType *DSAT
2722        = dyn_cast<DependentSizedArrayType>(ATy))
2723    return cast<ArrayType>(
2724                     getDependentSizedArrayType(NewEltTy,
2725                                                DSAT->getSizeExpr() ?
2726                                              DSAT->getSizeExpr()->Retain() : 0,
2727                                                DSAT->getSizeModifier(),
2728                                              DSAT->getIndexTypeCVRQualifiers(),
2729                                                DSAT->getBracketsRange()));
2730
2731  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
2732  return cast<ArrayType>(getVariableArrayType(NewEltTy,
2733                                              VAT->getSizeExpr() ?
2734                                              VAT->getSizeExpr()->Retain() : 0,
2735                                              VAT->getSizeModifier(),
2736                                              VAT->getIndexTypeCVRQualifiers(),
2737                                              VAT->getBracketsRange()));
2738}
2739
2740
2741/// getArrayDecayedType - Return the properly qualified result of decaying the
2742/// specified array type to a pointer.  This operation is non-trivial when
2743/// handling typedefs etc.  The canonical type of "T" must be an array type,
2744/// this returns a pointer to a properly qualified element of the array.
2745///
2746/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
2747QualType ASTContext::getArrayDecayedType(QualType Ty) {
2748  // Get the element type with 'getAsArrayType' so that we don't lose any
2749  // typedefs in the element type of the array.  This also handles propagation
2750  // of type qualifiers from the array type into the element type if present
2751  // (C99 6.7.3p8).
2752  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
2753  assert(PrettyArrayType && "Not an array type!");
2754
2755  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
2756
2757  // int x[restrict 4] ->  int *restrict
2758  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
2759}
2760
2761QualType ASTContext::getBaseElementType(QualType QT) {
2762  QualifierCollector Qs;
2763  while (const ArrayType *AT = getAsArrayType(QualType(Qs.strip(QT), 0)))
2764    QT = AT->getElementType();
2765  return Qs.apply(QT);
2766}
2767
2768QualType ASTContext::getBaseElementType(const ArrayType *AT) {
2769  QualType ElemTy = AT->getElementType();
2770
2771  if (const ArrayType *AT = getAsArrayType(ElemTy))
2772    return getBaseElementType(AT);
2773
2774  return ElemTy;
2775}
2776
2777/// getConstantArrayElementCount - Returns number of constant array elements.
2778uint64_t
2779ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
2780  uint64_t ElementCount = 1;
2781  do {
2782    ElementCount *= CA->getSize().getZExtValue();
2783    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
2784  } while (CA);
2785  return ElementCount;
2786}
2787
2788/// getFloatingRank - Return a relative rank for floating point types.
2789/// This routine will assert if passed a built-in type that isn't a float.
2790static FloatingRank getFloatingRank(QualType T) {
2791  if (const ComplexType *CT = T->getAs<ComplexType>())
2792    return getFloatingRank(CT->getElementType());
2793
2794  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
2795  switch (T->getAs<BuiltinType>()->getKind()) {
2796  default: assert(0 && "getFloatingRank(): not a floating type");
2797  case BuiltinType::Float:      return FloatRank;
2798  case BuiltinType::Double:     return DoubleRank;
2799  case BuiltinType::LongDouble: return LongDoubleRank;
2800  }
2801}
2802
2803/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
2804/// point or a complex type (based on typeDomain/typeSize).
2805/// 'typeDomain' is a real floating point or complex type.
2806/// 'typeSize' is a real floating point or complex type.
2807QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
2808                                                       QualType Domain) const {
2809  FloatingRank EltRank = getFloatingRank(Size);
2810  if (Domain->isComplexType()) {
2811    switch (EltRank) {
2812    default: assert(0 && "getFloatingRank(): illegal value for rank");
2813    case FloatRank:      return FloatComplexTy;
2814    case DoubleRank:     return DoubleComplexTy;
2815    case LongDoubleRank: return LongDoubleComplexTy;
2816    }
2817  }
2818
2819  assert(Domain->isRealFloatingType() && "Unknown domain!");
2820  switch (EltRank) {
2821  default: assert(0 && "getFloatingRank(): illegal value for rank");
2822  case FloatRank:      return FloatTy;
2823  case DoubleRank:     return DoubleTy;
2824  case LongDoubleRank: return LongDoubleTy;
2825  }
2826}
2827
2828/// getFloatingTypeOrder - Compare the rank of the two specified floating
2829/// point types, ignoring the domain of the type (i.e. 'double' ==
2830/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2831/// LHS < RHS, return -1.
2832int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) {
2833  FloatingRank LHSR = getFloatingRank(LHS);
2834  FloatingRank RHSR = getFloatingRank(RHS);
2835
2836  if (LHSR == RHSR)
2837    return 0;
2838  if (LHSR > RHSR)
2839    return 1;
2840  return -1;
2841}
2842
2843/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
2844/// routine will assert if passed a built-in type that isn't an integer or enum,
2845/// or if it is not canonicalized.
2846unsigned ASTContext::getIntegerRank(Type *T) {
2847  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
2848  if (EnumType* ET = dyn_cast<EnumType>(T))
2849    T = ET->getDecl()->getPromotionType().getTypePtr();
2850
2851  if (T->isSpecificBuiltinType(BuiltinType::WChar))
2852    T = getFromTargetType(Target.getWCharType()).getTypePtr();
2853
2854  if (T->isSpecificBuiltinType(BuiltinType::Char16))
2855    T = getFromTargetType(Target.getChar16Type()).getTypePtr();
2856
2857  if (T->isSpecificBuiltinType(BuiltinType::Char32))
2858    T = getFromTargetType(Target.getChar32Type()).getTypePtr();
2859
2860  switch (cast<BuiltinType>(T)->getKind()) {
2861  default: assert(0 && "getIntegerRank(): not a built-in integer");
2862  case BuiltinType::Bool:
2863    return 1 + (getIntWidth(BoolTy) << 3);
2864  case BuiltinType::Char_S:
2865  case BuiltinType::Char_U:
2866  case BuiltinType::SChar:
2867  case BuiltinType::UChar:
2868    return 2 + (getIntWidth(CharTy) << 3);
2869  case BuiltinType::Short:
2870  case BuiltinType::UShort:
2871    return 3 + (getIntWidth(ShortTy) << 3);
2872  case BuiltinType::Int:
2873  case BuiltinType::UInt:
2874    return 4 + (getIntWidth(IntTy) << 3);
2875  case BuiltinType::Long:
2876  case BuiltinType::ULong:
2877    return 5 + (getIntWidth(LongTy) << 3);
2878  case BuiltinType::LongLong:
2879  case BuiltinType::ULongLong:
2880    return 6 + (getIntWidth(LongLongTy) << 3);
2881  case BuiltinType::Int128:
2882  case BuiltinType::UInt128:
2883    return 7 + (getIntWidth(Int128Ty) << 3);
2884  }
2885}
2886
2887/// \brief Whether this is a promotable bitfield reference according
2888/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
2889///
2890/// \returns the type this bit-field will promote to, or NULL if no
2891/// promotion occurs.
2892QualType ASTContext::isPromotableBitField(Expr *E) {
2893  if (E->isTypeDependent() || E->isValueDependent())
2894    return QualType();
2895
2896  FieldDecl *Field = E->getBitField();
2897  if (!Field)
2898    return QualType();
2899
2900  QualType FT = Field->getType();
2901
2902  llvm::APSInt BitWidthAP = Field->getBitWidth()->EvaluateAsInt(*this);
2903  uint64_t BitWidth = BitWidthAP.getZExtValue();
2904  uint64_t IntSize = getTypeSize(IntTy);
2905  // GCC extension compatibility: if the bit-field size is less than or equal
2906  // to the size of int, it gets promoted no matter what its type is.
2907  // For instance, unsigned long bf : 4 gets promoted to signed int.
2908  if (BitWidth < IntSize)
2909    return IntTy;
2910
2911  if (BitWidth == IntSize)
2912    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
2913
2914  // Types bigger than int are not subject to promotions, and therefore act
2915  // like the base type.
2916  // FIXME: This doesn't quite match what gcc does, but what gcc does here
2917  // is ridiculous.
2918  return QualType();
2919}
2920
2921/// getPromotedIntegerType - Returns the type that Promotable will
2922/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
2923/// integer type.
2924QualType ASTContext::getPromotedIntegerType(QualType Promotable) {
2925  assert(!Promotable.isNull());
2926  assert(Promotable->isPromotableIntegerType());
2927  if (const EnumType *ET = Promotable->getAs<EnumType>())
2928    return ET->getDecl()->getPromotionType();
2929  if (Promotable->isSignedIntegerType())
2930    return IntTy;
2931  uint64_t PromotableSize = getTypeSize(Promotable);
2932  uint64_t IntSize = getTypeSize(IntTy);
2933  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
2934  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
2935}
2936
2937/// getIntegerTypeOrder - Returns the highest ranked integer type:
2938/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2939/// LHS < RHS, return -1.
2940int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) {
2941  Type *LHSC = getCanonicalType(LHS).getTypePtr();
2942  Type *RHSC = getCanonicalType(RHS).getTypePtr();
2943  if (LHSC == RHSC) return 0;
2944
2945  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
2946  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
2947
2948  unsigned LHSRank = getIntegerRank(LHSC);
2949  unsigned RHSRank = getIntegerRank(RHSC);
2950
2951  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
2952    if (LHSRank == RHSRank) return 0;
2953    return LHSRank > RHSRank ? 1 : -1;
2954  }
2955
2956  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
2957  if (LHSUnsigned) {
2958    // If the unsigned [LHS] type is larger, return it.
2959    if (LHSRank >= RHSRank)
2960      return 1;
2961
2962    // If the signed type can represent all values of the unsigned type, it
2963    // wins.  Because we are dealing with 2's complement and types that are
2964    // powers of two larger than each other, this is always safe.
2965    return -1;
2966  }
2967
2968  // If the unsigned [RHS] type is larger, return it.
2969  if (RHSRank >= LHSRank)
2970    return -1;
2971
2972  // If the signed type can represent all values of the unsigned type, it
2973  // wins.  Because we are dealing with 2's complement and types that are
2974  // powers of two larger than each other, this is always safe.
2975  return 1;
2976}
2977
2978static RecordDecl *
2979CreateRecordDecl(ASTContext &Ctx, RecordDecl::TagKind TK, DeclContext *DC,
2980                 SourceLocation L, IdentifierInfo *Id) {
2981  if (Ctx.getLangOptions().CPlusPlus)
2982    return CXXRecordDecl::Create(Ctx, TK, DC, L, Id);
2983  else
2984    return RecordDecl::Create(Ctx, TK, DC, L, Id);
2985}
2986
2987// getCFConstantStringType - Return the type used for constant CFStrings.
2988QualType ASTContext::getCFConstantStringType() {
2989  if (!CFConstantStringTypeDecl) {
2990    CFConstantStringTypeDecl =
2991      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
2992                       &Idents.get("NSConstantString"));
2993    CFConstantStringTypeDecl->startDefinition();
2994
2995    QualType FieldTypes[4];
2996
2997    // const int *isa;
2998    FieldTypes[0] = getPointerType(IntTy.withConst());
2999    // int flags;
3000    FieldTypes[1] = IntTy;
3001    // const char *str;
3002    FieldTypes[2] = getPointerType(CharTy.withConst());
3003    // long length;
3004    FieldTypes[3] = LongTy;
3005
3006    // Create fields
3007    for (unsigned i = 0; i < 4; ++i) {
3008      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3009                                           SourceLocation(), 0,
3010                                           FieldTypes[i], /*TInfo=*/0,
3011                                           /*BitWidth=*/0,
3012                                           /*Mutable=*/false);
3013      Field->setAccess(AS_public);
3014      CFConstantStringTypeDecl->addDecl(Field);
3015    }
3016
3017    CFConstantStringTypeDecl->completeDefinition();
3018  }
3019
3020  return getTagDeclType(CFConstantStringTypeDecl);
3021}
3022
3023void ASTContext::setCFConstantStringType(QualType T) {
3024  const RecordType *Rec = T->getAs<RecordType>();
3025  assert(Rec && "Invalid CFConstantStringType");
3026  CFConstantStringTypeDecl = Rec->getDecl();
3027}
3028
3029// getNSConstantStringType - Return the type used for constant NSStrings.
3030QualType ASTContext::getNSConstantStringType() {
3031  if (!NSConstantStringTypeDecl) {
3032    NSConstantStringTypeDecl =
3033    CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3034                     &Idents.get("__builtin_NSString"));
3035    NSConstantStringTypeDecl->startDefinition();
3036
3037    QualType FieldTypes[3];
3038
3039    // const int *isa;
3040    FieldTypes[0] = getPointerType(IntTy.withConst());
3041    // const char *str;
3042    FieldTypes[1] = getPointerType(CharTy.withConst());
3043    // unsigned int length;
3044    FieldTypes[2] = UnsignedIntTy;
3045
3046    // Create fields
3047    for (unsigned i = 0; i < 3; ++i) {
3048      FieldDecl *Field = FieldDecl::Create(*this, NSConstantStringTypeDecl,
3049                                           SourceLocation(), 0,
3050                                           FieldTypes[i], /*TInfo=*/0,
3051                                           /*BitWidth=*/0,
3052                                           /*Mutable=*/false);
3053      Field->setAccess(AS_public);
3054      NSConstantStringTypeDecl->addDecl(Field);
3055    }
3056
3057    NSConstantStringTypeDecl->completeDefinition();
3058  }
3059
3060  return getTagDeclType(NSConstantStringTypeDecl);
3061}
3062
3063void ASTContext::setNSConstantStringType(QualType T) {
3064  const RecordType *Rec = T->getAs<RecordType>();
3065  assert(Rec && "Invalid NSConstantStringType");
3066  NSConstantStringTypeDecl = Rec->getDecl();
3067}
3068
3069QualType ASTContext::getObjCFastEnumerationStateType() {
3070  if (!ObjCFastEnumerationStateTypeDecl) {
3071    ObjCFastEnumerationStateTypeDecl =
3072      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3073                       &Idents.get("__objcFastEnumerationState"));
3074    ObjCFastEnumerationStateTypeDecl->startDefinition();
3075
3076    QualType FieldTypes[] = {
3077      UnsignedLongTy,
3078      getPointerType(ObjCIdTypedefType),
3079      getPointerType(UnsignedLongTy),
3080      getConstantArrayType(UnsignedLongTy,
3081                           llvm::APInt(32, 5), ArrayType::Normal, 0)
3082    };
3083
3084    for (size_t i = 0; i < 4; ++i) {
3085      FieldDecl *Field = FieldDecl::Create(*this,
3086                                           ObjCFastEnumerationStateTypeDecl,
3087                                           SourceLocation(), 0,
3088                                           FieldTypes[i], /*TInfo=*/0,
3089                                           /*BitWidth=*/0,
3090                                           /*Mutable=*/false);
3091      Field->setAccess(AS_public);
3092      ObjCFastEnumerationStateTypeDecl->addDecl(Field);
3093    }
3094    if (getLangOptions().CPlusPlus)
3095      if (CXXRecordDecl *CXXRD =
3096            dyn_cast<CXXRecordDecl>(ObjCFastEnumerationStateTypeDecl))
3097        CXXRD->setEmpty(false);
3098
3099    ObjCFastEnumerationStateTypeDecl->completeDefinition();
3100  }
3101
3102  return getTagDeclType(ObjCFastEnumerationStateTypeDecl);
3103}
3104
3105QualType ASTContext::getBlockDescriptorType() {
3106  if (BlockDescriptorType)
3107    return getTagDeclType(BlockDescriptorType);
3108
3109  RecordDecl *T;
3110  // FIXME: Needs the FlagAppleBlock bit.
3111  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3112                       &Idents.get("__block_descriptor"));
3113  T->startDefinition();
3114
3115  QualType FieldTypes[] = {
3116    UnsignedLongTy,
3117    UnsignedLongTy,
3118  };
3119
3120  const char *FieldNames[] = {
3121    "reserved",
3122    "Size"
3123  };
3124
3125  for (size_t i = 0; i < 2; ++i) {
3126    FieldDecl *Field = FieldDecl::Create(*this,
3127                                         T,
3128                                         SourceLocation(),
3129                                         &Idents.get(FieldNames[i]),
3130                                         FieldTypes[i], /*TInfo=*/0,
3131                                         /*BitWidth=*/0,
3132                                         /*Mutable=*/false);
3133    Field->setAccess(AS_public);
3134    T->addDecl(Field);
3135  }
3136
3137  T->completeDefinition();
3138
3139  BlockDescriptorType = T;
3140
3141  return getTagDeclType(BlockDescriptorType);
3142}
3143
3144void ASTContext::setBlockDescriptorType(QualType T) {
3145  const RecordType *Rec = T->getAs<RecordType>();
3146  assert(Rec && "Invalid BlockDescriptorType");
3147  BlockDescriptorType = Rec->getDecl();
3148}
3149
3150QualType ASTContext::getBlockDescriptorExtendedType() {
3151  if (BlockDescriptorExtendedType)
3152    return getTagDeclType(BlockDescriptorExtendedType);
3153
3154  RecordDecl *T;
3155  // FIXME: Needs the FlagAppleBlock bit.
3156  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3157                       &Idents.get("__block_descriptor_withcopydispose"));
3158  T->startDefinition();
3159
3160  QualType FieldTypes[] = {
3161    UnsignedLongTy,
3162    UnsignedLongTy,
3163    getPointerType(VoidPtrTy),
3164    getPointerType(VoidPtrTy)
3165  };
3166
3167  const char *FieldNames[] = {
3168    "reserved",
3169    "Size",
3170    "CopyFuncPtr",
3171    "DestroyFuncPtr"
3172  };
3173
3174  for (size_t i = 0; i < 4; ++i) {
3175    FieldDecl *Field = FieldDecl::Create(*this,
3176                                         T,
3177                                         SourceLocation(),
3178                                         &Idents.get(FieldNames[i]),
3179                                         FieldTypes[i], /*TInfo=*/0,
3180                                         /*BitWidth=*/0,
3181                                         /*Mutable=*/false);
3182    Field->setAccess(AS_public);
3183    T->addDecl(Field);
3184  }
3185
3186  T->completeDefinition();
3187
3188  BlockDescriptorExtendedType = T;
3189
3190  return getTagDeclType(BlockDescriptorExtendedType);
3191}
3192
3193void ASTContext::setBlockDescriptorExtendedType(QualType T) {
3194  const RecordType *Rec = T->getAs<RecordType>();
3195  assert(Rec && "Invalid BlockDescriptorType");
3196  BlockDescriptorExtendedType = Rec->getDecl();
3197}
3198
3199bool ASTContext::BlockRequiresCopying(QualType Ty) {
3200  if (Ty->isBlockPointerType())
3201    return true;
3202  if (isObjCNSObjectType(Ty))
3203    return true;
3204  if (Ty->isObjCObjectPointerType())
3205    return true;
3206  return false;
3207}
3208
3209QualType ASTContext::BuildByRefType(llvm::StringRef DeclName, QualType Ty) {
3210  //  type = struct __Block_byref_1_X {
3211  //    void *__isa;
3212  //    struct __Block_byref_1_X *__forwarding;
3213  //    unsigned int __flags;
3214  //    unsigned int __size;
3215  //    void *__copy_helper;            // as needed
3216  //    void *__destroy_help            // as needed
3217  //    int X;
3218  //  } *
3219
3220  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3221
3222  // FIXME: Move up
3223  llvm::SmallString<36> Name;
3224  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3225                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3226  RecordDecl *T;
3227  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3228                       &Idents.get(Name.str()));
3229  T->startDefinition();
3230  QualType Int32Ty = IntTy;
3231  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3232  QualType FieldTypes[] = {
3233    getPointerType(VoidPtrTy),
3234    getPointerType(getTagDeclType(T)),
3235    Int32Ty,
3236    Int32Ty,
3237    getPointerType(VoidPtrTy),
3238    getPointerType(VoidPtrTy),
3239    Ty
3240  };
3241
3242  llvm::StringRef FieldNames[] = {
3243    "__isa",
3244    "__forwarding",
3245    "__flags",
3246    "__size",
3247    "__copy_helper",
3248    "__destroy_helper",
3249    DeclName,
3250  };
3251
3252  for (size_t i = 0; i < 7; ++i) {
3253    if (!HasCopyAndDispose && i >=4 && i <= 5)
3254      continue;
3255    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3256                                         &Idents.get(FieldNames[i]),
3257                                         FieldTypes[i], /*TInfo=*/0,
3258                                         /*BitWidth=*/0, /*Mutable=*/false);
3259    Field->setAccess(AS_public);
3260    T->addDecl(Field);
3261  }
3262
3263  T->completeDefinition();
3264
3265  return getPointerType(getTagDeclType(T));
3266}
3267
3268
3269QualType ASTContext::getBlockParmType(
3270  bool BlockHasCopyDispose,
3271  llvm::SmallVectorImpl<const Expr *> &Layout) {
3272
3273  // FIXME: Move up
3274  llvm::SmallString<36> Name;
3275  llvm::raw_svector_ostream(Name) << "__block_literal_"
3276                                  << ++UniqueBlockParmTypeID;
3277  RecordDecl *T;
3278  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3279                       &Idents.get(Name.str()));
3280  T->startDefinition();
3281  QualType FieldTypes[] = {
3282    getPointerType(VoidPtrTy),
3283    IntTy,
3284    IntTy,
3285    getPointerType(VoidPtrTy),
3286    (BlockHasCopyDispose ?
3287     getPointerType(getBlockDescriptorExtendedType()) :
3288     getPointerType(getBlockDescriptorType()))
3289  };
3290
3291  const char *FieldNames[] = {
3292    "__isa",
3293    "__flags",
3294    "__reserved",
3295    "__FuncPtr",
3296    "__descriptor"
3297  };
3298
3299  for (size_t i = 0; i < 5; ++i) {
3300    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3301                                         &Idents.get(FieldNames[i]),
3302                                         FieldTypes[i], /*TInfo=*/0,
3303                                         /*BitWidth=*/0, /*Mutable=*/false);
3304    Field->setAccess(AS_public);
3305    T->addDecl(Field);
3306  }
3307
3308  for (unsigned i = 0; i < Layout.size(); ++i) {
3309    const Expr *E = Layout[i];
3310
3311    QualType FieldType = E->getType();
3312    IdentifierInfo *FieldName = 0;
3313    if (isa<CXXThisExpr>(E)) {
3314      FieldName = &Idents.get("this");
3315    } else if (const BlockDeclRefExpr *BDRE = dyn_cast<BlockDeclRefExpr>(E)) {
3316      const ValueDecl *D = BDRE->getDecl();
3317      FieldName = D->getIdentifier();
3318      if (BDRE->isByRef())
3319        FieldType = BuildByRefType(D->getName(), FieldType);
3320    } else {
3321      // Padding.
3322      assert(isa<ConstantArrayType>(FieldType) &&
3323             isa<DeclRefExpr>(E) &&
3324             !cast<DeclRefExpr>(E)->getDecl()->getDeclName() &&
3325             "doesn't match characteristics of padding decl");
3326    }
3327
3328    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3329                                         FieldName, FieldType, /*TInfo=*/0,
3330                                         /*BitWidth=*/0, /*Mutable=*/false);
3331    Field->setAccess(AS_public);
3332    T->addDecl(Field);
3333  }
3334
3335  T->completeDefinition();
3336
3337  return getPointerType(getTagDeclType(T));
3338}
3339
3340void ASTContext::setObjCFastEnumerationStateType(QualType T) {
3341  const RecordType *Rec = T->getAs<RecordType>();
3342  assert(Rec && "Invalid ObjCFAstEnumerationStateType");
3343  ObjCFastEnumerationStateTypeDecl = Rec->getDecl();
3344}
3345
3346// This returns true if a type has been typedefed to BOOL:
3347// typedef <type> BOOL;
3348static bool isTypeTypedefedAsBOOL(QualType T) {
3349  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3350    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3351      return II->isStr("BOOL");
3352
3353  return false;
3354}
3355
3356/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3357/// purpose.
3358CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) {
3359  CharUnits sz = getTypeSizeInChars(type);
3360
3361  // Make all integer and enum types at least as large as an int
3362  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3363    sz = std::max(sz, getTypeSizeInChars(IntTy));
3364  // Treat arrays as pointers, since that's how they're passed in.
3365  else if (type->isArrayType())
3366    sz = getTypeSizeInChars(VoidPtrTy);
3367  return sz;
3368}
3369
3370static inline
3371std::string charUnitsToString(const CharUnits &CU) {
3372  return llvm::itostr(CU.getQuantity());
3373}
3374
3375/// getObjCEncodingForBlockDecl - Return the encoded type for this block
3376/// declaration.
3377void ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr,
3378                                             std::string& S) {
3379  const BlockDecl *Decl = Expr->getBlockDecl();
3380  QualType BlockTy =
3381      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3382  // Encode result type.
3383  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3384  // Compute size of all parameters.
3385  // Start with computing size of a pointer in number of bytes.
3386  // FIXME: There might(should) be a better way of doing this computation!
3387  SourceLocation Loc;
3388  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3389  CharUnits ParmOffset = PtrSize;
3390  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3391       E = Decl->param_end(); PI != E; ++PI) {
3392    QualType PType = (*PI)->getType();
3393    CharUnits sz = getObjCEncodingTypeSize(PType);
3394    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3395    ParmOffset += sz;
3396  }
3397  // Size of the argument frame
3398  S += charUnitsToString(ParmOffset);
3399  // Block pointer and offset.
3400  S += "@?0";
3401  ParmOffset = PtrSize;
3402
3403  // Argument types.
3404  ParmOffset = PtrSize;
3405  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3406       Decl->param_end(); PI != E; ++PI) {
3407    ParmVarDecl *PVDecl = *PI;
3408    QualType PType = PVDecl->getOriginalType();
3409    if (const ArrayType *AT =
3410          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3411      // Use array's original type only if it has known number of
3412      // elements.
3413      if (!isa<ConstantArrayType>(AT))
3414        PType = PVDecl->getType();
3415    } else if (PType->isFunctionType())
3416      PType = PVDecl->getType();
3417    getObjCEncodingForType(PType, S);
3418    S += charUnitsToString(ParmOffset);
3419    ParmOffset += getObjCEncodingTypeSize(PType);
3420  }
3421}
3422
3423/// getObjCEncodingForMethodDecl - Return the encoded type for this method
3424/// declaration.
3425void ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
3426                                              std::string& S) {
3427  // FIXME: This is not very efficient.
3428  // Encode type qualifer, 'in', 'inout', etc. for the return type.
3429  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
3430  // Encode result type.
3431  getObjCEncodingForType(Decl->getResultType(), S);
3432  // Compute size of all parameters.
3433  // Start with computing size of a pointer in number of bytes.
3434  // FIXME: There might(should) be a better way of doing this computation!
3435  SourceLocation Loc;
3436  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3437  // The first two arguments (self and _cmd) are pointers; account for
3438  // their size.
3439  CharUnits ParmOffset = 2 * PtrSize;
3440  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3441       E = Decl->sel_param_end(); PI != E; ++PI) {
3442    QualType PType = (*PI)->getType();
3443    CharUnits sz = getObjCEncodingTypeSize(PType);
3444    assert (sz.isPositive() &&
3445        "getObjCEncodingForMethodDecl - Incomplete param type");
3446    ParmOffset += sz;
3447  }
3448  S += charUnitsToString(ParmOffset);
3449  S += "@0:";
3450  S += charUnitsToString(PtrSize);
3451
3452  // Argument types.
3453  ParmOffset = 2 * PtrSize;
3454  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3455       E = Decl->sel_param_end(); PI != E; ++PI) {
3456    ParmVarDecl *PVDecl = *PI;
3457    QualType PType = PVDecl->getOriginalType();
3458    if (const ArrayType *AT =
3459          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3460      // Use array's original type only if it has known number of
3461      // elements.
3462      if (!isa<ConstantArrayType>(AT))
3463        PType = PVDecl->getType();
3464    } else if (PType->isFunctionType())
3465      PType = PVDecl->getType();
3466    // Process argument qualifiers for user supplied arguments; such as,
3467    // 'in', 'inout', etc.
3468    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
3469    getObjCEncodingForType(PType, S);
3470    S += charUnitsToString(ParmOffset);
3471    ParmOffset += getObjCEncodingTypeSize(PType);
3472  }
3473}
3474
3475/// getObjCEncodingForPropertyDecl - Return the encoded type for this
3476/// property declaration. If non-NULL, Container must be either an
3477/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
3478/// NULL when getting encodings for protocol properties.
3479/// Property attributes are stored as a comma-delimited C string. The simple
3480/// attributes readonly and bycopy are encoded as single characters. The
3481/// parametrized attributes, getter=name, setter=name, and ivar=name, are
3482/// encoded as single characters, followed by an identifier. Property types
3483/// are also encoded as a parametrized attribute. The characters used to encode
3484/// these attributes are defined by the following enumeration:
3485/// @code
3486/// enum PropertyAttributes {
3487/// kPropertyReadOnly = 'R',   // property is read-only.
3488/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
3489/// kPropertyByref = '&',  // property is a reference to the value last assigned
3490/// kPropertyDynamic = 'D',    // property is dynamic
3491/// kPropertyGetter = 'G',     // followed by getter selector name
3492/// kPropertySetter = 'S',     // followed by setter selector name
3493/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
3494/// kPropertyType = 't'              // followed by old-style type encoding.
3495/// kPropertyWeak = 'W'              // 'weak' property
3496/// kPropertyStrong = 'P'            // property GC'able
3497/// kPropertyNonAtomic = 'N'         // property non-atomic
3498/// };
3499/// @endcode
3500void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
3501                                                const Decl *Container,
3502                                                std::string& S) {
3503  // Collect information from the property implementation decl(s).
3504  bool Dynamic = false;
3505  ObjCPropertyImplDecl *SynthesizePID = 0;
3506
3507  // FIXME: Duplicated code due to poor abstraction.
3508  if (Container) {
3509    if (const ObjCCategoryImplDecl *CID =
3510        dyn_cast<ObjCCategoryImplDecl>(Container)) {
3511      for (ObjCCategoryImplDecl::propimpl_iterator
3512             i = CID->propimpl_begin(), e = CID->propimpl_end();
3513           i != e; ++i) {
3514        ObjCPropertyImplDecl *PID = *i;
3515        if (PID->getPropertyDecl() == PD) {
3516          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3517            Dynamic = true;
3518          } else {
3519            SynthesizePID = PID;
3520          }
3521        }
3522      }
3523    } else {
3524      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
3525      for (ObjCCategoryImplDecl::propimpl_iterator
3526             i = OID->propimpl_begin(), e = OID->propimpl_end();
3527           i != e; ++i) {
3528        ObjCPropertyImplDecl *PID = *i;
3529        if (PID->getPropertyDecl() == PD) {
3530          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3531            Dynamic = true;
3532          } else {
3533            SynthesizePID = PID;
3534          }
3535        }
3536      }
3537    }
3538  }
3539
3540  // FIXME: This is not very efficient.
3541  S = "T";
3542
3543  // Encode result type.
3544  // GCC has some special rules regarding encoding of properties which
3545  // closely resembles encoding of ivars.
3546  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
3547                             true /* outermost type */,
3548                             true /* encoding for property */);
3549
3550  if (PD->isReadOnly()) {
3551    S += ",R";
3552  } else {
3553    switch (PD->getSetterKind()) {
3554    case ObjCPropertyDecl::Assign: break;
3555    case ObjCPropertyDecl::Copy:   S += ",C"; break;
3556    case ObjCPropertyDecl::Retain: S += ",&"; break;
3557    }
3558  }
3559
3560  // It really isn't clear at all what this means, since properties
3561  // are "dynamic by default".
3562  if (Dynamic)
3563    S += ",D";
3564
3565  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
3566    S += ",N";
3567
3568  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
3569    S += ",G";
3570    S += PD->getGetterName().getAsString();
3571  }
3572
3573  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
3574    S += ",S";
3575    S += PD->getSetterName().getAsString();
3576  }
3577
3578  if (SynthesizePID) {
3579    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
3580    S += ",V";
3581    S += OID->getNameAsString();
3582  }
3583
3584  // FIXME: OBJCGC: weak & strong
3585}
3586
3587/// getLegacyIntegralTypeEncoding -
3588/// Another legacy compatibility encoding: 32-bit longs are encoded as
3589/// 'l' or 'L' , but not always.  For typedefs, we need to use
3590/// 'i' or 'I' instead if encoding a struct field, or a pointer!
3591///
3592void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
3593  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
3594    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
3595      if (BT->getKind() == BuiltinType::ULong &&
3596          ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3597        PointeeTy = UnsignedIntTy;
3598      else
3599        if (BT->getKind() == BuiltinType::Long &&
3600            ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3601          PointeeTy = IntTy;
3602    }
3603  }
3604}
3605
3606void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
3607                                        const FieldDecl *Field) {
3608  // We follow the behavior of gcc, expanding structures which are
3609  // directly pointed to, and expanding embedded structures. Note that
3610  // these rules are sufficient to prevent recursive encoding of the
3611  // same type.
3612  getObjCEncodingForTypeImpl(T, S, true, true, Field,
3613                             true /* outermost type */);
3614}
3615
3616static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
3617    switch (T->getAs<BuiltinType>()->getKind()) {
3618    default: assert(0 && "Unhandled builtin type kind");
3619    case BuiltinType::Void:       return 'v';
3620    case BuiltinType::Bool:       return 'B';
3621    case BuiltinType::Char_U:
3622    case BuiltinType::UChar:      return 'C';
3623    case BuiltinType::UShort:     return 'S';
3624    case BuiltinType::UInt:       return 'I';
3625    case BuiltinType::ULong:
3626        return
3627          (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'L' : 'Q';
3628    case BuiltinType::UInt128:    return 'T';
3629    case BuiltinType::ULongLong:  return 'Q';
3630    case BuiltinType::Char_S:
3631    case BuiltinType::SChar:      return 'c';
3632    case BuiltinType::Short:      return 's';
3633    case BuiltinType::WChar:
3634    case BuiltinType::Int:        return 'i';
3635    case BuiltinType::Long:
3636      return
3637        (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'l' : 'q';
3638    case BuiltinType::LongLong:   return 'q';
3639    case BuiltinType::Int128:     return 't';
3640    case BuiltinType::Float:      return 'f';
3641    case BuiltinType::Double:     return 'd';
3642    case BuiltinType::LongDouble: return 'd';
3643    }
3644}
3645
3646static void EncodeBitField(const ASTContext *Context, std::string& S,
3647                           QualType T, const FieldDecl *FD) {
3648  const Expr *E = FD->getBitWidth();
3649  assert(E && "bitfield width not there - getObjCEncodingForTypeImpl");
3650  ASTContext *Ctx = const_cast<ASTContext*>(Context);
3651  S += 'b';
3652  // The NeXT runtime encodes bit fields as b followed by the number of bits.
3653  // The GNU runtime requires more information; bitfields are encoded as b,
3654  // then the offset (in bits) of the first element, then the type of the
3655  // bitfield, then the size in bits.  For example, in this structure:
3656  //
3657  // struct
3658  // {
3659  //    int integer;
3660  //    int flags:2;
3661  // };
3662  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
3663  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
3664  // information is not especially sensible, but we're stuck with it for
3665  // compatibility with GCC, although providing it breaks anything that
3666  // actually uses runtime introspection and wants to work on both runtimes...
3667  if (!Ctx->getLangOptions().NeXTRuntime) {
3668    const RecordDecl *RD = FD->getParent();
3669    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
3670    // FIXME: This same linear search is also used in ExprConstant - it might
3671    // be better if the FieldDecl stored its offset.  We'd be increasing the
3672    // size of the object slightly, but saving some time every time it is used.
3673    unsigned i = 0;
3674    for (RecordDecl::field_iterator Field = RD->field_begin(),
3675                                 FieldEnd = RD->field_end();
3676         Field != FieldEnd; (void)++Field, ++i) {
3677      if (*Field == FD)
3678        break;
3679    }
3680    S += llvm::utostr(RL.getFieldOffset(i));
3681    S += ObjCEncodingForPrimitiveKind(Context, T);
3682  }
3683  unsigned N = E->EvaluateAsInt(*Ctx).getZExtValue();
3684  S += llvm::utostr(N);
3685}
3686
3687// FIXME: Use SmallString for accumulating string.
3688void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
3689                                            bool ExpandPointedToStructures,
3690                                            bool ExpandStructures,
3691                                            const FieldDecl *FD,
3692                                            bool OutermostType,
3693                                            bool EncodingProperty) {
3694  if (T->getAs<BuiltinType>()) {
3695    if (FD && FD->isBitField())
3696      return EncodeBitField(this, S, T, FD);
3697    S += ObjCEncodingForPrimitiveKind(this, T);
3698    return;
3699  }
3700
3701  if (const ComplexType *CT = T->getAs<ComplexType>()) {
3702    S += 'j';
3703    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
3704                               false);
3705    return;
3706  }
3707
3708  // encoding for pointer or r3eference types.
3709  QualType PointeeTy;
3710  if (const PointerType *PT = T->getAs<PointerType>()) {
3711    if (PT->isObjCSelType()) {
3712      S += ':';
3713      return;
3714    }
3715    PointeeTy = PT->getPointeeType();
3716  }
3717  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3718    PointeeTy = RT->getPointeeType();
3719  if (!PointeeTy.isNull()) {
3720    bool isReadOnly = false;
3721    // For historical/compatibility reasons, the read-only qualifier of the
3722    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
3723    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
3724    // Also, do not emit the 'r' for anything but the outermost type!
3725    if (isa<TypedefType>(T.getTypePtr())) {
3726      if (OutermostType && T.isConstQualified()) {
3727        isReadOnly = true;
3728        S += 'r';
3729      }
3730    } else if (OutermostType) {
3731      QualType P = PointeeTy;
3732      while (P->getAs<PointerType>())
3733        P = P->getAs<PointerType>()->getPointeeType();
3734      if (P.isConstQualified()) {
3735        isReadOnly = true;
3736        S += 'r';
3737      }
3738    }
3739    if (isReadOnly) {
3740      // Another legacy compatibility encoding. Some ObjC qualifier and type
3741      // combinations need to be rearranged.
3742      // Rewrite "in const" from "nr" to "rn"
3743      if (llvm::StringRef(S).endswith("nr"))
3744        S.replace(S.end()-2, S.end(), "rn");
3745    }
3746
3747    if (PointeeTy->isCharType()) {
3748      // char pointer types should be encoded as '*' unless it is a
3749      // type that has been typedef'd to 'BOOL'.
3750      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
3751        S += '*';
3752        return;
3753      }
3754    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
3755      // GCC binary compat: Need to convert "struct objc_class *" to "#".
3756      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
3757        S += '#';
3758        return;
3759      }
3760      // GCC binary compat: Need to convert "struct objc_object *" to "@".
3761      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
3762        S += '@';
3763        return;
3764      }
3765      // fall through...
3766    }
3767    S += '^';
3768    getLegacyIntegralTypeEncoding(PointeeTy);
3769
3770    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
3771                               NULL);
3772    return;
3773  }
3774
3775  if (const ArrayType *AT =
3776      // Ignore type qualifiers etc.
3777        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
3778    if (isa<IncompleteArrayType>(AT)) {
3779      // Incomplete arrays are encoded as a pointer to the array element.
3780      S += '^';
3781
3782      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3783                                 false, ExpandStructures, FD);
3784    } else {
3785      S += '[';
3786
3787      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
3788        S += llvm::utostr(CAT->getSize().getZExtValue());
3789      else {
3790        //Variable length arrays are encoded as a regular array with 0 elements.
3791        assert(isa<VariableArrayType>(AT) && "Unknown array type!");
3792        S += '0';
3793      }
3794
3795      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3796                                 false, ExpandStructures, FD);
3797      S += ']';
3798    }
3799    return;
3800  }
3801
3802  if (T->getAs<FunctionType>()) {
3803    S += '?';
3804    return;
3805  }
3806
3807  if (const RecordType *RTy = T->getAs<RecordType>()) {
3808    RecordDecl *RDecl = RTy->getDecl();
3809    S += RDecl->isUnion() ? '(' : '{';
3810    // Anonymous structures print as '?'
3811    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
3812      S += II->getName();
3813      if (ClassTemplateSpecializationDecl *Spec
3814          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
3815        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
3816        std::string TemplateArgsStr
3817          = TemplateSpecializationType::PrintTemplateArgumentList(
3818                                            TemplateArgs.getFlatArgumentList(),
3819                                            TemplateArgs.flat_size(),
3820                                            (*this).PrintingPolicy);
3821
3822        S += TemplateArgsStr;
3823      }
3824    } else {
3825      S += '?';
3826    }
3827    if (ExpandStructures) {
3828      S += '=';
3829      for (RecordDecl::field_iterator Field = RDecl->field_begin(),
3830                                   FieldEnd = RDecl->field_end();
3831           Field != FieldEnd; ++Field) {
3832        if (FD) {
3833          S += '"';
3834          S += Field->getNameAsString();
3835          S += '"';
3836        }
3837
3838        // Special case bit-fields.
3839        if (Field->isBitField()) {
3840          getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
3841                                     (*Field));
3842        } else {
3843          QualType qt = Field->getType();
3844          getLegacyIntegralTypeEncoding(qt);
3845          getObjCEncodingForTypeImpl(qt, S, false, true,
3846                                     FD);
3847        }
3848      }
3849    }
3850    S += RDecl->isUnion() ? ')' : '}';
3851    return;
3852  }
3853
3854  if (T->isEnumeralType()) {
3855    if (FD && FD->isBitField())
3856      EncodeBitField(this, S, T, FD);
3857    else
3858      S += 'i';
3859    return;
3860  }
3861
3862  if (T->isBlockPointerType()) {
3863    S += "@?"; // Unlike a pointer-to-function, which is "^?".
3864    return;
3865  }
3866
3867  // Ignore protocol qualifiers when mangling at this level.
3868  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
3869    T = OT->getBaseType();
3870
3871  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
3872    // @encode(class_name)
3873    ObjCInterfaceDecl *OI = OIT->getDecl();
3874    S += '{';
3875    const IdentifierInfo *II = OI->getIdentifier();
3876    S += II->getName();
3877    S += '=';
3878    llvm::SmallVector<ObjCIvarDecl*, 32> Ivars;
3879    DeepCollectObjCIvars(OI, true, Ivars);
3880    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
3881      FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
3882      if (Field->isBitField())
3883        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
3884      else
3885        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
3886    }
3887    S += '}';
3888    return;
3889  }
3890
3891  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
3892    if (OPT->isObjCIdType()) {
3893      S += '@';
3894      return;
3895    }
3896
3897    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
3898      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
3899      // Since this is a binary compatibility issue, need to consult with runtime
3900      // folks. Fortunately, this is a *very* obsure construct.
3901      S += '#';
3902      return;
3903    }
3904
3905    if (OPT->isObjCQualifiedIdType()) {
3906      getObjCEncodingForTypeImpl(getObjCIdType(), S,
3907                                 ExpandPointedToStructures,
3908                                 ExpandStructures, FD);
3909      if (FD || EncodingProperty) {
3910        // Note that we do extended encoding of protocol qualifer list
3911        // Only when doing ivar or property encoding.
3912        S += '"';
3913        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3914             E = OPT->qual_end(); I != E; ++I) {
3915          S += '<';
3916          S += (*I)->getNameAsString();
3917          S += '>';
3918        }
3919        S += '"';
3920      }
3921      return;
3922    }
3923
3924    QualType PointeeTy = OPT->getPointeeType();
3925    if (!EncodingProperty &&
3926        isa<TypedefType>(PointeeTy.getTypePtr())) {
3927      // Another historical/compatibility reason.
3928      // We encode the underlying type which comes out as
3929      // {...};
3930      S += '^';
3931      getObjCEncodingForTypeImpl(PointeeTy, S,
3932                                 false, ExpandPointedToStructures,
3933                                 NULL);
3934      return;
3935    }
3936
3937    S += '@';
3938    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
3939      S += '"';
3940      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
3941      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3942           E = OPT->qual_end(); I != E; ++I) {
3943        S += '<';
3944        S += (*I)->getNameAsString();
3945        S += '>';
3946      }
3947      S += '"';
3948    }
3949    return;
3950  }
3951
3952  // gcc just blithely ignores member pointers.
3953  // TODO: maybe there should be a mangling for these
3954  if (T->getAs<MemberPointerType>())
3955    return;
3956
3957  assert(0 && "@encode for type not implemented!");
3958}
3959
3960void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
3961                                                 std::string& S) const {
3962  if (QT & Decl::OBJC_TQ_In)
3963    S += 'n';
3964  if (QT & Decl::OBJC_TQ_Inout)
3965    S += 'N';
3966  if (QT & Decl::OBJC_TQ_Out)
3967    S += 'o';
3968  if (QT & Decl::OBJC_TQ_Bycopy)
3969    S += 'O';
3970  if (QT & Decl::OBJC_TQ_Byref)
3971    S += 'R';
3972  if (QT & Decl::OBJC_TQ_Oneway)
3973    S += 'V';
3974}
3975
3976void ASTContext::setBuiltinVaListType(QualType T) {
3977  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
3978
3979  BuiltinVaListType = T;
3980}
3981
3982void ASTContext::setObjCIdType(QualType T) {
3983  ObjCIdTypedefType = T;
3984}
3985
3986void ASTContext::setObjCSelType(QualType T) {
3987  ObjCSelTypedefType = T;
3988}
3989
3990void ASTContext::setObjCProtoType(QualType QT) {
3991  ObjCProtoType = QT;
3992}
3993
3994void ASTContext::setObjCClassType(QualType T) {
3995  ObjCClassTypedefType = T;
3996}
3997
3998void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
3999  assert(ObjCConstantStringType.isNull() &&
4000         "'NSConstantString' type already set!");
4001
4002  ObjCConstantStringType = getObjCInterfaceType(Decl);
4003}
4004
4005/// \brief Retrieve the template name that corresponds to a non-empty
4006/// lookup.
4007TemplateName ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4008                                                   UnresolvedSetIterator End) {
4009  unsigned size = End - Begin;
4010  assert(size > 1 && "set is not overloaded!");
4011
4012  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4013                          size * sizeof(FunctionTemplateDecl*));
4014  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4015
4016  NamedDecl **Storage = OT->getStorage();
4017  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4018    NamedDecl *D = *I;
4019    assert(isa<FunctionTemplateDecl>(D) ||
4020           (isa<UsingShadowDecl>(D) &&
4021            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4022    *Storage++ = D;
4023  }
4024
4025  return TemplateName(OT);
4026}
4027
4028/// \brief Retrieve the template name that represents a qualified
4029/// template name such as \c std::vector.
4030TemplateName ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4031                                                  bool TemplateKeyword,
4032                                                  TemplateDecl *Template) {
4033  // FIXME: Canonicalization?
4034  llvm::FoldingSetNodeID ID;
4035  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4036
4037  void *InsertPos = 0;
4038  QualifiedTemplateName *QTN =
4039    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4040  if (!QTN) {
4041    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4042    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4043  }
4044
4045  return TemplateName(QTN);
4046}
4047
4048/// \brief Retrieve the template name that represents a dependent
4049/// template name such as \c MetaFun::template apply.
4050TemplateName ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4051                                                  const IdentifierInfo *Name) {
4052  assert((!NNS || NNS->isDependent()) &&
4053         "Nested name specifier must be dependent");
4054
4055  llvm::FoldingSetNodeID ID;
4056  DependentTemplateName::Profile(ID, NNS, Name);
4057
4058  void *InsertPos = 0;
4059  DependentTemplateName *QTN =
4060    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4061
4062  if (QTN)
4063    return TemplateName(QTN);
4064
4065  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4066  if (CanonNNS == NNS) {
4067    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4068  } else {
4069    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4070    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4071    DependentTemplateName *CheckQTN =
4072      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4073    assert(!CheckQTN && "Dependent type name canonicalization broken");
4074    (void)CheckQTN;
4075  }
4076
4077  DependentTemplateNames.InsertNode(QTN, InsertPos);
4078  return TemplateName(QTN);
4079}
4080
4081/// \brief Retrieve the template name that represents a dependent
4082/// template name such as \c MetaFun::template operator+.
4083TemplateName
4084ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4085                                     OverloadedOperatorKind Operator) {
4086  assert((!NNS || NNS->isDependent()) &&
4087         "Nested name specifier must be dependent");
4088
4089  llvm::FoldingSetNodeID ID;
4090  DependentTemplateName::Profile(ID, NNS, Operator);
4091
4092  void *InsertPos = 0;
4093  DependentTemplateName *QTN
4094    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4095
4096  if (QTN)
4097    return TemplateName(QTN);
4098
4099  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4100  if (CanonNNS == NNS) {
4101    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4102  } else {
4103    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4104    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4105
4106    DependentTemplateName *CheckQTN
4107      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4108    assert(!CheckQTN && "Dependent template name canonicalization broken");
4109    (void)CheckQTN;
4110  }
4111
4112  DependentTemplateNames.InsertNode(QTN, InsertPos);
4113  return TemplateName(QTN);
4114}
4115
4116/// getFromTargetType - Given one of the integer types provided by
4117/// TargetInfo, produce the corresponding type. The unsigned @p Type
4118/// is actually a value of type @c TargetInfo::IntType.
4119CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4120  switch (Type) {
4121  case TargetInfo::NoInt: return CanQualType();
4122  case TargetInfo::SignedShort: return ShortTy;
4123  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4124  case TargetInfo::SignedInt: return IntTy;
4125  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4126  case TargetInfo::SignedLong: return LongTy;
4127  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4128  case TargetInfo::SignedLongLong: return LongLongTy;
4129  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4130  }
4131
4132  assert(false && "Unhandled TargetInfo::IntType value");
4133  return CanQualType();
4134}
4135
4136//===----------------------------------------------------------------------===//
4137//                        Type Predicates.
4138//===----------------------------------------------------------------------===//
4139
4140/// isObjCNSObjectType - Return true if this is an NSObject object using
4141/// NSObject attribute on a c-style pointer type.
4142/// FIXME - Make it work directly on types.
4143/// FIXME: Move to Type.
4144///
4145bool ASTContext::isObjCNSObjectType(QualType Ty) const {
4146  if (TypedefType *TDT = dyn_cast<TypedefType>(Ty)) {
4147    if (TypedefDecl *TD = TDT->getDecl())
4148      if (TD->getAttr<ObjCNSObjectAttr>())
4149        return true;
4150  }
4151  return false;
4152}
4153
4154/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4155/// garbage collection attribute.
4156///
4157Qualifiers::GC ASTContext::getObjCGCAttrKind(const QualType &Ty) const {
4158  Qualifiers::GC GCAttrs = Qualifiers::GCNone;
4159  if (getLangOptions().ObjC1 &&
4160      getLangOptions().getGCMode() != LangOptions::NonGC) {
4161    GCAttrs = Ty.getObjCGCAttr();
4162    // Default behavious under objective-c's gc is for objective-c pointers
4163    // (or pointers to them) be treated as though they were declared
4164    // as __strong.
4165    if (GCAttrs == Qualifiers::GCNone) {
4166      if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4167        GCAttrs = Qualifiers::Strong;
4168      else if (Ty->isPointerType())
4169        return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4170    }
4171    // Non-pointers have none gc'able attribute regardless of the attribute
4172    // set on them.
4173    else if (!Ty->isAnyPointerType() && !Ty->isBlockPointerType())
4174      return Qualifiers::GCNone;
4175  }
4176  return GCAttrs;
4177}
4178
4179//===----------------------------------------------------------------------===//
4180//                        Type Compatibility Testing
4181//===----------------------------------------------------------------------===//
4182
4183/// areCompatVectorTypes - Return true if the two specified vector types are
4184/// compatible.
4185static bool areCompatVectorTypes(const VectorType *LHS,
4186                                 const VectorType *RHS) {
4187  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
4188  return LHS->getElementType() == RHS->getElementType() &&
4189         LHS->getNumElements() == RHS->getNumElements();
4190}
4191
4192bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
4193                                          QualType SecondVec) {
4194  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
4195  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
4196
4197  if (hasSameUnqualifiedType(FirstVec, SecondVec))
4198    return true;
4199
4200  // AltiVec vectors types are identical to equivalent GCC vector types
4201  const VectorType *First = FirstVec->getAs<VectorType>();
4202  const VectorType *Second = SecondVec->getAs<VectorType>();
4203  if ((((First->getAltiVecSpecific() == VectorType::AltiVec) &&
4204        (Second->getAltiVecSpecific() == VectorType::NotAltiVec)) ||
4205       ((First->getAltiVecSpecific() == VectorType::NotAltiVec) &&
4206        (Second->getAltiVecSpecific() == VectorType::AltiVec))) &&
4207      hasSameType(First->getElementType(), Second->getElementType()) &&
4208      (First->getNumElements() == Second->getNumElements()))
4209    return true;
4210
4211  return false;
4212}
4213
4214//===----------------------------------------------------------------------===//
4215// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
4216//===----------------------------------------------------------------------===//
4217
4218/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
4219/// inheritance hierarchy of 'rProto'.
4220bool ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
4221                                                ObjCProtocolDecl *rProto) {
4222  if (lProto == rProto)
4223    return true;
4224  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
4225       E = rProto->protocol_end(); PI != E; ++PI)
4226    if (ProtocolCompatibleWithProtocol(lProto, *PI))
4227      return true;
4228  return false;
4229}
4230
4231/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
4232/// return true if lhs's protocols conform to rhs's protocol; false
4233/// otherwise.
4234bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
4235  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
4236    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
4237  return false;
4238}
4239
4240/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
4241/// Class<p1, ...>.
4242bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
4243                                                      QualType rhs) {
4244  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
4245  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4246  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
4247
4248  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4249       E = lhsQID->qual_end(); I != E; ++I) {
4250    bool match = false;
4251    ObjCProtocolDecl *lhsProto = *I;
4252    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4253         E = rhsOPT->qual_end(); J != E; ++J) {
4254      ObjCProtocolDecl *rhsProto = *J;
4255      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
4256        match = true;
4257        break;
4258      }
4259    }
4260    if (!match)
4261      return false;
4262  }
4263  return true;
4264}
4265
4266/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
4267/// ObjCQualifiedIDType.
4268bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
4269                                                   bool compare) {
4270  // Allow id<P..> and an 'id' or void* type in all cases.
4271  if (lhs->isVoidPointerType() ||
4272      lhs->isObjCIdType() || lhs->isObjCClassType())
4273    return true;
4274  else if (rhs->isVoidPointerType() ||
4275           rhs->isObjCIdType() || rhs->isObjCClassType())
4276    return true;
4277
4278  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
4279    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4280
4281    if (!rhsOPT) return false;
4282
4283    if (rhsOPT->qual_empty()) {
4284      // If the RHS is a unqualified interface pointer "NSString*",
4285      // make sure we check the class hierarchy.
4286      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4287        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4288             E = lhsQID->qual_end(); I != E; ++I) {
4289          // when comparing an id<P> on lhs with a static type on rhs,
4290          // see if static class implements all of id's protocols, directly or
4291          // through its super class and categories.
4292          if (!rhsID->ClassImplementsProtocol(*I, true))
4293            return false;
4294        }
4295      }
4296      // If there are no qualifiers and no interface, we have an 'id'.
4297      return true;
4298    }
4299    // Both the right and left sides have qualifiers.
4300    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4301         E = lhsQID->qual_end(); I != E; ++I) {
4302      ObjCProtocolDecl *lhsProto = *I;
4303      bool match = false;
4304
4305      // when comparing an id<P> on lhs with a static type on rhs,
4306      // see if static class implements all of id's protocols, directly or
4307      // through its super class and categories.
4308      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4309           E = rhsOPT->qual_end(); J != E; ++J) {
4310        ObjCProtocolDecl *rhsProto = *J;
4311        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4312            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4313          match = true;
4314          break;
4315        }
4316      }
4317      // If the RHS is a qualified interface pointer "NSString<P>*",
4318      // make sure we check the class hierarchy.
4319      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4320        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4321             E = lhsQID->qual_end(); I != E; ++I) {
4322          // when comparing an id<P> on lhs with a static type on rhs,
4323          // see if static class implements all of id's protocols, directly or
4324          // through its super class and categories.
4325          if (rhsID->ClassImplementsProtocol(*I, true)) {
4326            match = true;
4327            break;
4328          }
4329        }
4330      }
4331      if (!match)
4332        return false;
4333    }
4334
4335    return true;
4336  }
4337
4338  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
4339  assert(rhsQID && "One of the LHS/RHS should be id<x>");
4340
4341  if (const ObjCObjectPointerType *lhsOPT =
4342        lhs->getAsObjCInterfacePointerType()) {
4343    if (lhsOPT->qual_empty()) {
4344      bool match = false;
4345      if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
4346        for (ObjCObjectPointerType::qual_iterator I = rhsQID->qual_begin(),
4347             E = rhsQID->qual_end(); I != E; ++I) {
4348          // when comparing an id<P> on rhs with a static type on lhs,
4349          // static class must implement all of id's protocols directly or
4350          // indirectly through its super class.
4351          if (lhsID->ClassImplementsProtocol(*I, true)) {
4352            match = true;
4353            break;
4354          }
4355        }
4356        if (!match)
4357          return false;
4358      }
4359      return true;
4360    }
4361    // Both the right and left sides have qualifiers.
4362    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
4363         E = lhsOPT->qual_end(); I != E; ++I) {
4364      ObjCProtocolDecl *lhsProto = *I;
4365      bool match = false;
4366
4367      // when comparing an id<P> on lhs with a static type on rhs,
4368      // see if static class implements all of id's protocols, directly or
4369      // through its super class and categories.
4370      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4371           E = rhsQID->qual_end(); J != E; ++J) {
4372        ObjCProtocolDecl *rhsProto = *J;
4373        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4374            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4375          match = true;
4376          break;
4377        }
4378      }
4379      if (!match)
4380        return false;
4381    }
4382    return true;
4383  }
4384  return false;
4385}
4386
4387/// canAssignObjCInterfaces - Return true if the two interface types are
4388/// compatible for assignment from RHS to LHS.  This handles validation of any
4389/// protocol qualifiers on the LHS or RHS.
4390///
4391bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
4392                                         const ObjCObjectPointerType *RHSOPT) {
4393  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4394  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4395
4396  // If either type represents the built-in 'id' or 'Class' types, return true.
4397  if (LHS->isObjCUnqualifiedIdOrClass() ||
4398      RHS->isObjCUnqualifiedIdOrClass())
4399    return true;
4400
4401  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
4402    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4403                                             QualType(RHSOPT,0),
4404                                             false);
4405
4406  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
4407    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
4408                                                QualType(RHSOPT,0));
4409
4410  // If we have 2 user-defined types, fall into that path.
4411  if (LHS->getInterface() && RHS->getInterface())
4412    return canAssignObjCInterfaces(LHS, RHS);
4413
4414  return false;
4415}
4416
4417/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
4418/// for providing type-safty for objective-c pointers used to pass/return
4419/// arguments in block literals. When passed as arguments, passing 'A*' where
4420/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
4421/// not OK. For the return type, the opposite is not OK.
4422bool ASTContext::canAssignObjCInterfacesInBlockPointer(
4423                                         const ObjCObjectPointerType *LHSOPT,
4424                                         const ObjCObjectPointerType *RHSOPT) {
4425  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
4426    return true;
4427
4428  if (LHSOPT->isObjCBuiltinType()) {
4429    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
4430  }
4431
4432  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
4433    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4434                                             QualType(RHSOPT,0),
4435                                             false);
4436
4437  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
4438  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
4439  if (LHS && RHS)  { // We have 2 user-defined types.
4440    if (LHS != RHS) {
4441      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
4442        return false;
4443      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
4444        return true;
4445    }
4446    else
4447      return true;
4448  }
4449  return false;
4450}
4451
4452/// getIntersectionOfProtocols - This routine finds the intersection of set
4453/// of protocols inherited from two distinct objective-c pointer objects.
4454/// It is used to build composite qualifier list of the composite type of
4455/// the conditional expression involving two objective-c pointer objects.
4456static
4457void getIntersectionOfProtocols(ASTContext &Context,
4458                                const ObjCObjectPointerType *LHSOPT,
4459                                const ObjCObjectPointerType *RHSOPT,
4460      llvm::SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
4461
4462  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4463  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4464  assert(LHS->getInterface() && "LHS must have an interface base");
4465  assert(RHS->getInterface() && "RHS must have an interface base");
4466
4467  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
4468  unsigned LHSNumProtocols = LHS->getNumProtocols();
4469  if (LHSNumProtocols > 0)
4470    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
4471  else {
4472    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4473    Context.CollectInheritedProtocols(LHS->getInterface(),
4474                                      LHSInheritedProtocols);
4475    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
4476                                LHSInheritedProtocols.end());
4477  }
4478
4479  unsigned RHSNumProtocols = RHS->getNumProtocols();
4480  if (RHSNumProtocols > 0) {
4481    ObjCProtocolDecl **RHSProtocols =
4482      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
4483    for (unsigned i = 0; i < RHSNumProtocols; ++i)
4484      if (InheritedProtocolSet.count(RHSProtocols[i]))
4485        IntersectionOfProtocols.push_back(RHSProtocols[i]);
4486  }
4487  else {
4488    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
4489    Context.CollectInheritedProtocols(RHS->getInterface(),
4490                                      RHSInheritedProtocols);
4491    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4492         RHSInheritedProtocols.begin(),
4493         E = RHSInheritedProtocols.end(); I != E; ++I)
4494      if (InheritedProtocolSet.count((*I)))
4495        IntersectionOfProtocols.push_back((*I));
4496  }
4497}
4498
4499/// areCommonBaseCompatible - Returns common base class of the two classes if
4500/// one found. Note that this is O'2 algorithm. But it will be called as the
4501/// last type comparison in a ?-exp of ObjC pointer types before a
4502/// warning is issued. So, its invokation is extremely rare.
4503QualType ASTContext::areCommonBaseCompatible(
4504                                          const ObjCObjectPointerType *Lptr,
4505                                          const ObjCObjectPointerType *Rptr) {
4506  const ObjCObjectType *LHS = Lptr->getObjectType();
4507  const ObjCObjectType *RHS = Rptr->getObjectType();
4508  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
4509  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
4510  if (!LDecl || !RDecl)
4511    return QualType();
4512
4513  while ((LDecl = LDecl->getSuperClass())) {
4514    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
4515    if (canAssignObjCInterfaces(LHS, RHS)) {
4516      llvm::SmallVector<ObjCProtocolDecl *, 8> Protocols;
4517      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
4518
4519      QualType Result = QualType(LHS, 0);
4520      if (!Protocols.empty())
4521        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
4522      Result = getObjCObjectPointerType(Result);
4523      return Result;
4524    }
4525  }
4526
4527  return QualType();
4528}
4529
4530bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
4531                                         const ObjCObjectType *RHS) {
4532  assert(LHS->getInterface() && "LHS is not an interface type");
4533  assert(RHS->getInterface() && "RHS is not an interface type");
4534
4535  // Verify that the base decls are compatible: the RHS must be a subclass of
4536  // the LHS.
4537  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
4538    return false;
4539
4540  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
4541  // protocol qualified at all, then we are good.
4542  if (LHS->getNumProtocols() == 0)
4543    return true;
4544
4545  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't, then it
4546  // isn't a superset.
4547  if (RHS->getNumProtocols() == 0)
4548    return true;  // FIXME: should return false!
4549
4550  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
4551                                     LHSPE = LHS->qual_end();
4552       LHSPI != LHSPE; LHSPI++) {
4553    bool RHSImplementsProtocol = false;
4554
4555    // If the RHS doesn't implement the protocol on the left, the types
4556    // are incompatible.
4557    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
4558                                       RHSPE = RHS->qual_end();
4559         RHSPI != RHSPE; RHSPI++) {
4560      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
4561        RHSImplementsProtocol = true;
4562        break;
4563      }
4564    }
4565    // FIXME: For better diagnostics, consider passing back the protocol name.
4566    if (!RHSImplementsProtocol)
4567      return false;
4568  }
4569  // The RHS implements all protocols listed on the LHS.
4570  return true;
4571}
4572
4573bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
4574  // get the "pointed to" types
4575  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
4576  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
4577
4578  if (!LHSOPT || !RHSOPT)
4579    return false;
4580
4581  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
4582         canAssignObjCInterfaces(RHSOPT, LHSOPT);
4583}
4584
4585bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
4586  return canAssignObjCInterfaces(
4587                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
4588                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
4589}
4590
4591/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
4592/// both shall have the identically qualified version of a compatible type.
4593/// C99 6.2.7p1: Two types have compatible types if their types are the
4594/// same. See 6.7.[2,3,5] for additional rules.
4595bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
4596                                    bool CompareUnqualified) {
4597  if (getLangOptions().CPlusPlus)
4598    return hasSameType(LHS, RHS);
4599
4600  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
4601}
4602
4603bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
4604  return !mergeTypes(LHS, RHS, true).isNull();
4605}
4606
4607QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
4608                                        bool OfBlockPointer,
4609                                        bool Unqualified) {
4610  const FunctionType *lbase = lhs->getAs<FunctionType>();
4611  const FunctionType *rbase = rhs->getAs<FunctionType>();
4612  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
4613  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
4614  bool allLTypes = true;
4615  bool allRTypes = true;
4616
4617  // Check return type
4618  QualType retType;
4619  if (OfBlockPointer)
4620    retType = mergeTypes(rbase->getResultType(), lbase->getResultType(), true,
4621                         Unqualified);
4622  else
4623   retType = mergeTypes(lbase->getResultType(), rbase->getResultType(),
4624                        false, Unqualified);
4625  if (retType.isNull()) return QualType();
4626
4627  if (Unqualified)
4628    retType = retType.getUnqualifiedType();
4629
4630  CanQualType LRetType = getCanonicalType(lbase->getResultType());
4631  CanQualType RRetType = getCanonicalType(rbase->getResultType());
4632  if (Unqualified) {
4633    LRetType = LRetType.getUnqualifiedType();
4634    RRetType = RRetType.getUnqualifiedType();
4635  }
4636
4637  if (getCanonicalType(retType) != LRetType)
4638    allLTypes = false;
4639  if (getCanonicalType(retType) != RRetType)
4640    allRTypes = false;
4641  // FIXME: double check this
4642  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
4643  //                           rbase->getRegParmAttr() != 0 &&
4644  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
4645  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
4646  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
4647  unsigned RegParm = lbaseInfo.getRegParm() == 0 ? rbaseInfo.getRegParm() :
4648      lbaseInfo.getRegParm();
4649  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
4650  if (NoReturn != lbaseInfo.getNoReturn() ||
4651      RegParm != lbaseInfo.getRegParm())
4652    allLTypes = false;
4653  if (NoReturn != rbaseInfo.getNoReturn() ||
4654      RegParm != rbaseInfo.getRegParm())
4655    allRTypes = false;
4656  CallingConv lcc = lbaseInfo.getCC();
4657  CallingConv rcc = rbaseInfo.getCC();
4658  // Compatible functions must have compatible calling conventions
4659  if (!isSameCallConv(lcc, rcc))
4660    return QualType();
4661
4662  if (lproto && rproto) { // two C99 style function prototypes
4663    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
4664           "C++ shouldn't be here");
4665    unsigned lproto_nargs = lproto->getNumArgs();
4666    unsigned rproto_nargs = rproto->getNumArgs();
4667
4668    // Compatible functions must have the same number of arguments
4669    if (lproto_nargs != rproto_nargs)
4670      return QualType();
4671
4672    // Variadic and non-variadic functions aren't compatible
4673    if (lproto->isVariadic() != rproto->isVariadic())
4674      return QualType();
4675
4676    if (lproto->getTypeQuals() != rproto->getTypeQuals())
4677      return QualType();
4678
4679    // Check argument compatibility
4680    llvm::SmallVector<QualType, 10> types;
4681    for (unsigned i = 0; i < lproto_nargs; i++) {
4682      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
4683      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
4684      QualType argtype = mergeTypes(largtype, rargtype, OfBlockPointer,
4685                                    Unqualified);
4686      if (argtype.isNull()) return QualType();
4687
4688      if (Unqualified)
4689        argtype = argtype.getUnqualifiedType();
4690
4691      types.push_back(argtype);
4692      if (Unqualified) {
4693        largtype = largtype.getUnqualifiedType();
4694        rargtype = rargtype.getUnqualifiedType();
4695      }
4696
4697      if (getCanonicalType(argtype) != getCanonicalType(largtype))
4698        allLTypes = false;
4699      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
4700        allRTypes = false;
4701    }
4702    if (allLTypes) return lhs;
4703    if (allRTypes) return rhs;
4704    return getFunctionType(retType, types.begin(), types.size(),
4705                           lproto->isVariadic(), lproto->getTypeQuals(),
4706                           false, false, 0, 0,
4707                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4708  }
4709
4710  if (lproto) allRTypes = false;
4711  if (rproto) allLTypes = false;
4712
4713  const FunctionProtoType *proto = lproto ? lproto : rproto;
4714  if (proto) {
4715    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
4716    if (proto->isVariadic()) return QualType();
4717    // Check that the types are compatible with the types that
4718    // would result from default argument promotions (C99 6.7.5.3p15).
4719    // The only types actually affected are promotable integer
4720    // types and floats, which would be passed as a different
4721    // type depending on whether the prototype is visible.
4722    unsigned proto_nargs = proto->getNumArgs();
4723    for (unsigned i = 0; i < proto_nargs; ++i) {
4724      QualType argTy = proto->getArgType(i);
4725
4726      // Look at the promotion type of enum types, since that is the type used
4727      // to pass enum values.
4728      if (const EnumType *Enum = argTy->getAs<EnumType>())
4729        argTy = Enum->getDecl()->getPromotionType();
4730
4731      if (argTy->isPromotableIntegerType() ||
4732          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
4733        return QualType();
4734    }
4735
4736    if (allLTypes) return lhs;
4737    if (allRTypes) return rhs;
4738    return getFunctionType(retType, proto->arg_type_begin(),
4739                           proto->getNumArgs(), proto->isVariadic(),
4740                           proto->getTypeQuals(),
4741                           false, false, 0, 0,
4742                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4743  }
4744
4745  if (allLTypes) return lhs;
4746  if (allRTypes) return rhs;
4747  FunctionType::ExtInfo Info(NoReturn, RegParm, lcc);
4748  return getFunctionNoProtoType(retType, Info);
4749}
4750
4751QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
4752                                bool OfBlockPointer,
4753                                bool Unqualified) {
4754  // C++ [expr]: If an expression initially has the type "reference to T", the
4755  // type is adjusted to "T" prior to any further analysis, the expression
4756  // designates the object or function denoted by the reference, and the
4757  // expression is an lvalue unless the reference is an rvalue reference and
4758  // the expression is a function call (possibly inside parentheses).
4759  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
4760  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
4761
4762  if (Unqualified) {
4763    LHS = LHS.getUnqualifiedType();
4764    RHS = RHS.getUnqualifiedType();
4765  }
4766
4767  QualType LHSCan = getCanonicalType(LHS),
4768           RHSCan = getCanonicalType(RHS);
4769
4770  // If two types are identical, they are compatible.
4771  if (LHSCan == RHSCan)
4772    return LHS;
4773
4774  // If the qualifiers are different, the types aren't compatible... mostly.
4775  Qualifiers LQuals = LHSCan.getLocalQualifiers();
4776  Qualifiers RQuals = RHSCan.getLocalQualifiers();
4777  if (LQuals != RQuals) {
4778    // If any of these qualifiers are different, we have a type
4779    // mismatch.
4780    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
4781        LQuals.getAddressSpace() != RQuals.getAddressSpace())
4782      return QualType();
4783
4784    // Exactly one GC qualifier difference is allowed: __strong is
4785    // okay if the other type has no GC qualifier but is an Objective
4786    // C object pointer (i.e. implicitly strong by default).  We fix
4787    // this by pretending that the unqualified type was actually
4788    // qualified __strong.
4789    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
4790    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
4791    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
4792
4793    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
4794      return QualType();
4795
4796    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
4797      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
4798    }
4799    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
4800      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
4801    }
4802    return QualType();
4803  }
4804
4805  // Okay, qualifiers are equal.
4806
4807  Type::TypeClass LHSClass = LHSCan->getTypeClass();
4808  Type::TypeClass RHSClass = RHSCan->getTypeClass();
4809
4810  // We want to consider the two function types to be the same for these
4811  // comparisons, just force one to the other.
4812  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
4813  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
4814
4815  // Same as above for arrays
4816  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
4817    LHSClass = Type::ConstantArray;
4818  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
4819    RHSClass = Type::ConstantArray;
4820
4821  // ObjCInterfaces are just specialized ObjCObjects.
4822  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
4823  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
4824
4825  // Canonicalize ExtVector -> Vector.
4826  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
4827  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
4828
4829  // If the canonical type classes don't match.
4830  if (LHSClass != RHSClass) {
4831    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
4832    // a signed integer type, or an unsigned integer type.
4833    // Compatibility is based on the underlying type, not the promotion
4834    // type.
4835    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
4836      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
4837        return RHS;
4838    }
4839    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
4840      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
4841        return LHS;
4842    }
4843
4844    return QualType();
4845  }
4846
4847  // The canonical type classes match.
4848  switch (LHSClass) {
4849#define TYPE(Class, Base)
4850#define ABSTRACT_TYPE(Class, Base)
4851#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
4852#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
4853#define DEPENDENT_TYPE(Class, Base) case Type::Class:
4854#include "clang/AST/TypeNodes.def"
4855    assert(false && "Non-canonical and dependent types shouldn't get here");
4856    return QualType();
4857
4858  case Type::LValueReference:
4859  case Type::RValueReference:
4860  case Type::MemberPointer:
4861    assert(false && "C++ should never be in mergeTypes");
4862    return QualType();
4863
4864  case Type::ObjCInterface:
4865  case Type::IncompleteArray:
4866  case Type::VariableArray:
4867  case Type::FunctionProto:
4868  case Type::ExtVector:
4869    assert(false && "Types are eliminated above");
4870    return QualType();
4871
4872  case Type::Pointer:
4873  {
4874    // Merge two pointer types, while trying to preserve typedef info
4875    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
4876    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
4877    if (Unqualified) {
4878      LHSPointee = LHSPointee.getUnqualifiedType();
4879      RHSPointee = RHSPointee.getUnqualifiedType();
4880    }
4881    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
4882                                     Unqualified);
4883    if (ResultType.isNull()) return QualType();
4884    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
4885      return LHS;
4886    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
4887      return RHS;
4888    return getPointerType(ResultType);
4889  }
4890  case Type::BlockPointer:
4891  {
4892    // Merge two block pointer types, while trying to preserve typedef info
4893    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
4894    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
4895    if (Unqualified) {
4896      LHSPointee = LHSPointee.getUnqualifiedType();
4897      RHSPointee = RHSPointee.getUnqualifiedType();
4898    }
4899    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
4900                                     Unqualified);
4901    if (ResultType.isNull()) return QualType();
4902    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
4903      return LHS;
4904    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
4905      return RHS;
4906    return getBlockPointerType(ResultType);
4907  }
4908  case Type::ConstantArray:
4909  {
4910    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
4911    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
4912    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
4913      return QualType();
4914
4915    QualType LHSElem = getAsArrayType(LHS)->getElementType();
4916    QualType RHSElem = getAsArrayType(RHS)->getElementType();
4917    if (Unqualified) {
4918      LHSElem = LHSElem.getUnqualifiedType();
4919      RHSElem = RHSElem.getUnqualifiedType();
4920    }
4921
4922    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
4923    if (ResultType.isNull()) return QualType();
4924    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
4925      return LHS;
4926    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
4927      return RHS;
4928    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
4929                                          ArrayType::ArraySizeModifier(), 0);
4930    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
4931                                          ArrayType::ArraySizeModifier(), 0);
4932    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
4933    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
4934    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
4935      return LHS;
4936    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
4937      return RHS;
4938    if (LVAT) {
4939      // FIXME: This isn't correct! But tricky to implement because
4940      // the array's size has to be the size of LHS, but the type
4941      // has to be different.
4942      return LHS;
4943    }
4944    if (RVAT) {
4945      // FIXME: This isn't correct! But tricky to implement because
4946      // the array's size has to be the size of RHS, but the type
4947      // has to be different.
4948      return RHS;
4949    }
4950    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
4951    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
4952    return getIncompleteArrayType(ResultType,
4953                                  ArrayType::ArraySizeModifier(), 0);
4954  }
4955  case Type::FunctionNoProto:
4956    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
4957  case Type::Record:
4958  case Type::Enum:
4959    return QualType();
4960  case Type::Builtin:
4961    // Only exactly equal builtin types are compatible, which is tested above.
4962    return QualType();
4963  case Type::Complex:
4964    // Distinct complex types are incompatible.
4965    return QualType();
4966  case Type::Vector:
4967    // FIXME: The merged type should be an ExtVector!
4968    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
4969                             RHSCan->getAs<VectorType>()))
4970      return LHS;
4971    return QualType();
4972  case Type::ObjCObject: {
4973    // Check if the types are assignment compatible.
4974    // FIXME: This should be type compatibility, e.g. whether
4975    // "LHS x; RHS x;" at global scope is legal.
4976    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
4977    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
4978    if (canAssignObjCInterfaces(LHSIface, RHSIface))
4979      return LHS;
4980
4981    return QualType();
4982  }
4983  case Type::ObjCObjectPointer: {
4984    if (OfBlockPointer) {
4985      if (canAssignObjCInterfacesInBlockPointer(
4986                                          LHS->getAs<ObjCObjectPointerType>(),
4987                                          RHS->getAs<ObjCObjectPointerType>()))
4988      return LHS;
4989      return QualType();
4990    }
4991    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
4992                                RHS->getAs<ObjCObjectPointerType>()))
4993      return LHS;
4994
4995    return QualType();
4996    }
4997  }
4998
4999  return QualType();
5000}
5001
5002/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
5003/// 'RHS' attributes and returns the merged version; including for function
5004/// return types.
5005QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
5006  QualType LHSCan = getCanonicalType(LHS),
5007  RHSCan = getCanonicalType(RHS);
5008  // If two types are identical, they are compatible.
5009  if (LHSCan == RHSCan)
5010    return LHS;
5011  if (RHSCan->isFunctionType()) {
5012    if (!LHSCan->isFunctionType())
5013      return QualType();
5014    QualType OldReturnType =
5015      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
5016    QualType NewReturnType =
5017      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
5018    QualType ResReturnType =
5019      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
5020    if (ResReturnType.isNull())
5021      return QualType();
5022    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
5023      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
5024      // In either case, use OldReturnType to build the new function type.
5025      const FunctionType *F = LHS->getAs<FunctionType>();
5026      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
5027        FunctionType::ExtInfo Info = getFunctionExtInfo(LHS);
5028        QualType ResultType
5029          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
5030                                  FPT->getNumArgs(), FPT->isVariadic(),
5031                                  FPT->getTypeQuals(),
5032                                  FPT->hasExceptionSpec(),
5033                                  FPT->hasAnyExceptionSpec(),
5034                                  FPT->getNumExceptions(),
5035                                  FPT->exception_begin(),
5036                                  Info);
5037        return ResultType;
5038      }
5039    }
5040    return QualType();
5041  }
5042
5043  // If the qualifiers are different, the types can still be merged.
5044  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5045  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5046  if (LQuals != RQuals) {
5047    // If any of these qualifiers are different, we have a type mismatch.
5048    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5049        LQuals.getAddressSpace() != RQuals.getAddressSpace())
5050      return QualType();
5051
5052    // Exactly one GC qualifier difference is allowed: __strong is
5053    // okay if the other type has no GC qualifier but is an Objective
5054    // C object pointer (i.e. implicitly strong by default).  We fix
5055    // this by pretending that the unqualified type was actually
5056    // qualified __strong.
5057    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5058    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5059    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5060
5061    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5062      return QualType();
5063
5064    if (GC_L == Qualifiers::Strong)
5065      return LHS;
5066    if (GC_R == Qualifiers::Strong)
5067      return RHS;
5068    return QualType();
5069  }
5070
5071  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
5072    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5073    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5074    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
5075    if (ResQT == LHSBaseQT)
5076      return LHS;
5077    if (ResQT == RHSBaseQT)
5078      return RHS;
5079  }
5080  return QualType();
5081}
5082
5083//===----------------------------------------------------------------------===//
5084//                         Integer Predicates
5085//===----------------------------------------------------------------------===//
5086
5087unsigned ASTContext::getIntWidth(QualType T) {
5088  if (T->isBooleanType())
5089    return 1;
5090  if (EnumType *ET = dyn_cast<EnumType>(T))
5091    T = ET->getDecl()->getIntegerType();
5092  // For builtin types, just use the standard type sizing method
5093  return (unsigned)getTypeSize(T);
5094}
5095
5096QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
5097  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
5098
5099  // Turn <4 x signed int> -> <4 x unsigned int>
5100  if (const VectorType *VTy = T->getAs<VectorType>())
5101    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
5102             VTy->getNumElements(), VTy->getAltiVecSpecific());
5103
5104  // For enums, we return the unsigned version of the base type.
5105  if (const EnumType *ETy = T->getAs<EnumType>())
5106    T = ETy->getDecl()->getIntegerType();
5107
5108  const BuiltinType *BTy = T->getAs<BuiltinType>();
5109  assert(BTy && "Unexpected signed integer type");
5110  switch (BTy->getKind()) {
5111  case BuiltinType::Char_S:
5112  case BuiltinType::SChar:
5113    return UnsignedCharTy;
5114  case BuiltinType::Short:
5115    return UnsignedShortTy;
5116  case BuiltinType::Int:
5117    return UnsignedIntTy;
5118  case BuiltinType::Long:
5119    return UnsignedLongTy;
5120  case BuiltinType::LongLong:
5121    return UnsignedLongLongTy;
5122  case BuiltinType::Int128:
5123    return UnsignedInt128Ty;
5124  default:
5125    assert(0 && "Unexpected signed integer type");
5126    return QualType();
5127  }
5128}
5129
5130ExternalASTSource::~ExternalASTSource() { }
5131
5132void ExternalASTSource::PrintStats() { }
5133
5134
5135//===----------------------------------------------------------------------===//
5136//                          Builtin Type Computation
5137//===----------------------------------------------------------------------===//
5138
5139/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
5140/// pointer over the consumed characters.  This returns the resultant type.
5141static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
5142                                  ASTContext::GetBuiltinTypeError &Error,
5143                                  bool AllowTypeModifiers = true) {
5144  // Modifiers.
5145  int HowLong = 0;
5146  bool Signed = false, Unsigned = false;
5147
5148  // Read the modifiers first.
5149  bool Done = false;
5150  while (!Done) {
5151    switch (*Str++) {
5152    default: Done = true; --Str; break;
5153    case 'S':
5154      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
5155      assert(!Signed && "Can't use 'S' modifier multiple times!");
5156      Signed = true;
5157      break;
5158    case 'U':
5159      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
5160      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
5161      Unsigned = true;
5162      break;
5163    case 'L':
5164      assert(HowLong <= 2 && "Can't have LLLL modifier");
5165      ++HowLong;
5166      break;
5167    }
5168  }
5169
5170  QualType Type;
5171
5172  // Read the base type.
5173  switch (*Str++) {
5174  default: assert(0 && "Unknown builtin type letter!");
5175  case 'v':
5176    assert(HowLong == 0 && !Signed && !Unsigned &&
5177           "Bad modifiers used with 'v'!");
5178    Type = Context.VoidTy;
5179    break;
5180  case 'f':
5181    assert(HowLong == 0 && !Signed && !Unsigned &&
5182           "Bad modifiers used with 'f'!");
5183    Type = Context.FloatTy;
5184    break;
5185  case 'd':
5186    assert(HowLong < 2 && !Signed && !Unsigned &&
5187           "Bad modifiers used with 'd'!");
5188    if (HowLong)
5189      Type = Context.LongDoubleTy;
5190    else
5191      Type = Context.DoubleTy;
5192    break;
5193  case 's':
5194    assert(HowLong == 0 && "Bad modifiers used with 's'!");
5195    if (Unsigned)
5196      Type = Context.UnsignedShortTy;
5197    else
5198      Type = Context.ShortTy;
5199    break;
5200  case 'i':
5201    if (HowLong == 3)
5202      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
5203    else if (HowLong == 2)
5204      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
5205    else if (HowLong == 1)
5206      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
5207    else
5208      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
5209    break;
5210  case 'c':
5211    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
5212    if (Signed)
5213      Type = Context.SignedCharTy;
5214    else if (Unsigned)
5215      Type = Context.UnsignedCharTy;
5216    else
5217      Type = Context.CharTy;
5218    break;
5219  case 'b': // boolean
5220    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
5221    Type = Context.BoolTy;
5222    break;
5223  case 'z':  // size_t.
5224    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
5225    Type = Context.getSizeType();
5226    break;
5227  case 'F':
5228    Type = Context.getCFConstantStringType();
5229    break;
5230  case 'a':
5231    Type = Context.getBuiltinVaListType();
5232    assert(!Type.isNull() && "builtin va list type not initialized!");
5233    break;
5234  case 'A':
5235    // This is a "reference" to a va_list; however, what exactly
5236    // this means depends on how va_list is defined. There are two
5237    // different kinds of va_list: ones passed by value, and ones
5238    // passed by reference.  An example of a by-value va_list is
5239    // x86, where va_list is a char*. An example of by-ref va_list
5240    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
5241    // we want this argument to be a char*&; for x86-64, we want
5242    // it to be a __va_list_tag*.
5243    Type = Context.getBuiltinVaListType();
5244    assert(!Type.isNull() && "builtin va list type not initialized!");
5245    if (Type->isArrayType()) {
5246      Type = Context.getArrayDecayedType(Type);
5247    } else {
5248      Type = Context.getLValueReferenceType(Type);
5249    }
5250    break;
5251  case 'V': {
5252    char *End;
5253    unsigned NumElements = strtoul(Str, &End, 10);
5254    assert(End != Str && "Missing vector size");
5255
5256    Str = End;
5257
5258    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, false);
5259    // FIXME: Don't know what to do about AltiVec.
5260    Type = Context.getVectorType(ElementType, NumElements,
5261                                 VectorType::NotAltiVec);
5262    break;
5263  }
5264  case 'X': {
5265    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, false);
5266    Type = Context.getComplexType(ElementType);
5267    break;
5268  }
5269  case 'P':
5270    Type = Context.getFILEType();
5271    if (Type.isNull()) {
5272      Error = ASTContext::GE_Missing_stdio;
5273      return QualType();
5274    }
5275    break;
5276  case 'J':
5277    if (Signed)
5278      Type = Context.getsigjmp_bufType();
5279    else
5280      Type = Context.getjmp_bufType();
5281
5282    if (Type.isNull()) {
5283      Error = ASTContext::GE_Missing_setjmp;
5284      return QualType();
5285    }
5286    break;
5287  }
5288
5289  if (!AllowTypeModifiers)
5290    return Type;
5291
5292  Done = false;
5293  while (!Done) {
5294    switch (char c = *Str++) {
5295      default: Done = true; --Str; break;
5296      case '*':
5297      case '&':
5298        {
5299          // Both pointers and references can have their pointee types
5300          // qualified with an address space.
5301          char *End;
5302          unsigned AddrSpace = strtoul(Str, &End, 10);
5303          if (End != Str && AddrSpace != 0) {
5304            Type = Context.getAddrSpaceQualType(Type, AddrSpace);
5305            Str = End;
5306          }
5307        }
5308        if (c == '*')
5309          Type = Context.getPointerType(Type);
5310        else
5311          Type = Context.getLValueReferenceType(Type);
5312        break;
5313      // FIXME: There's no way to have a built-in with an rvalue ref arg.
5314      case 'C':
5315        Type = Type.withConst();
5316        break;
5317      case 'D':
5318        Type = Context.getVolatileType(Type);
5319        break;
5320    }
5321  }
5322
5323  return Type;
5324}
5325
5326/// GetBuiltinType - Return the type for the specified builtin.
5327QualType ASTContext::GetBuiltinType(unsigned id,
5328                                    GetBuiltinTypeError &Error) {
5329  const char *TypeStr = BuiltinInfo.GetTypeString(id);
5330
5331  llvm::SmallVector<QualType, 8> ArgTypes;
5332
5333  Error = GE_None;
5334  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error);
5335  if (Error != GE_None)
5336    return QualType();
5337  while (TypeStr[0] && TypeStr[0] != '.') {
5338    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error);
5339    if (Error != GE_None)
5340      return QualType();
5341
5342    // Do array -> pointer decay.  The builtin should use the decayed type.
5343    if (Ty->isArrayType())
5344      Ty = getArrayDecayedType(Ty);
5345
5346    ArgTypes.push_back(Ty);
5347  }
5348
5349  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
5350         "'.' should only occur at end of builtin type list!");
5351
5352  // handle untyped/variadic arguments "T c99Style();" or "T cppStyle(...);".
5353  if (ArgTypes.size() == 0 && TypeStr[0] == '.')
5354    return getFunctionNoProtoType(ResType);
5355
5356  // FIXME: Should we create noreturn types?
5357  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(),
5358                         TypeStr[0] == '.', 0, false, false, 0, 0,
5359                         FunctionType::ExtInfo());
5360}
5361
5362QualType
5363ASTContext::UsualArithmeticConversionsType(QualType lhs, QualType rhs) {
5364  // Perform the usual unary conversions. We do this early so that
5365  // integral promotions to "int" can allow us to exit early, in the
5366  // lhs == rhs check. Also, for conversion purposes, we ignore any
5367  // qualifiers.  For example, "const float" and "float" are
5368  // equivalent.
5369  if (lhs->isPromotableIntegerType())
5370    lhs = getPromotedIntegerType(lhs);
5371  else
5372    lhs = lhs.getUnqualifiedType();
5373  if (rhs->isPromotableIntegerType())
5374    rhs = getPromotedIntegerType(rhs);
5375  else
5376    rhs = rhs.getUnqualifiedType();
5377
5378  // If both types are identical, no conversion is needed.
5379  if (lhs == rhs)
5380    return lhs;
5381
5382  // If either side is a non-arithmetic type (e.g. a pointer), we are done.
5383  // The caller can deal with this (e.g. pointer + int).
5384  if (!lhs->isArithmeticType() || !rhs->isArithmeticType())
5385    return lhs;
5386
5387  // At this point, we have two different arithmetic types.
5388
5389  // Handle complex types first (C99 6.3.1.8p1).
5390  if (lhs->isComplexType() || rhs->isComplexType()) {
5391    // if we have an integer operand, the result is the complex type.
5392    if (rhs->isIntegerType() || rhs->isComplexIntegerType()) {
5393      // convert the rhs to the lhs complex type.
5394      return lhs;
5395    }
5396    if (lhs->isIntegerType() || lhs->isComplexIntegerType()) {
5397      // convert the lhs to the rhs complex type.
5398      return rhs;
5399    }
5400    // This handles complex/complex, complex/float, or float/complex.
5401    // When both operands are complex, the shorter operand is converted to the
5402    // type of the longer, and that is the type of the result. This corresponds
5403    // to what is done when combining two real floating-point operands.
5404    // The fun begins when size promotion occur across type domains.
5405    // From H&S 6.3.4: When one operand is complex and the other is a real
5406    // floating-point type, the less precise type is converted, within it's
5407    // real or complex domain, to the precision of the other type. For example,
5408    // when combining a "long double" with a "double _Complex", the
5409    // "double _Complex" is promoted to "long double _Complex".
5410    int result = getFloatingTypeOrder(lhs, rhs);
5411
5412    if (result > 0) { // The left side is bigger, convert rhs.
5413      rhs = getFloatingTypeOfSizeWithinDomain(lhs, rhs);
5414    } else if (result < 0) { // The right side is bigger, convert lhs.
5415      lhs = getFloatingTypeOfSizeWithinDomain(rhs, lhs);
5416    }
5417    // At this point, lhs and rhs have the same rank/size. Now, make sure the
5418    // domains match. This is a requirement for our implementation, C99
5419    // does not require this promotion.
5420    if (lhs != rhs) { // Domains don't match, we have complex/float mix.
5421      if (lhs->isRealFloatingType()) { // handle "double, _Complex double".
5422        return rhs;
5423      } else { // handle "_Complex double, double".
5424        return lhs;
5425      }
5426    }
5427    return lhs; // The domain/size match exactly.
5428  }
5429  // Now handle "real" floating types (i.e. float, double, long double).
5430  if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) {
5431    // if we have an integer operand, the result is the real floating type.
5432    if (rhs->isIntegerType()) {
5433      // convert rhs to the lhs floating point type.
5434      return lhs;
5435    }
5436    if (rhs->isComplexIntegerType()) {
5437      // convert rhs to the complex floating point type.
5438      return getComplexType(lhs);
5439    }
5440    if (lhs->isIntegerType()) {
5441      // convert lhs to the rhs floating point type.
5442      return rhs;
5443    }
5444    if (lhs->isComplexIntegerType()) {
5445      // convert lhs to the complex floating point type.
5446      return getComplexType(rhs);
5447    }
5448    // We have two real floating types, float/complex combos were handled above.
5449    // Convert the smaller operand to the bigger result.
5450    int result = getFloatingTypeOrder(lhs, rhs);
5451    if (result > 0) // convert the rhs
5452      return lhs;
5453    assert(result < 0 && "illegal float comparison");
5454    return rhs;   // convert the lhs
5455  }
5456  if (lhs->isComplexIntegerType() || rhs->isComplexIntegerType()) {
5457    // Handle GCC complex int extension.
5458    const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType();
5459    const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType();
5460
5461    if (lhsComplexInt && rhsComplexInt) {
5462      if (getIntegerTypeOrder(lhsComplexInt->getElementType(),
5463                              rhsComplexInt->getElementType()) >= 0)
5464        return lhs; // convert the rhs
5465      return rhs;
5466    } else if (lhsComplexInt && rhs->isIntegerType()) {
5467      // convert the rhs to the lhs complex type.
5468      return lhs;
5469    } else if (rhsComplexInt && lhs->isIntegerType()) {
5470      // convert the lhs to the rhs complex type.
5471      return rhs;
5472    }
5473  }
5474  // Finally, we have two differing integer types.
5475  // The rules for this case are in C99 6.3.1.8
5476  int compare = getIntegerTypeOrder(lhs, rhs);
5477  bool lhsSigned = lhs->hasSignedIntegerRepresentation(),
5478       rhsSigned = rhs->hasSignedIntegerRepresentation();
5479  QualType destType;
5480  if (lhsSigned == rhsSigned) {
5481    // Same signedness; use the higher-ranked type
5482    destType = compare >= 0 ? lhs : rhs;
5483  } else if (compare != (lhsSigned ? 1 : -1)) {
5484    // The unsigned type has greater than or equal rank to the
5485    // signed type, so use the unsigned type
5486    destType = lhsSigned ? rhs : lhs;
5487  } else if (getIntWidth(lhs) != getIntWidth(rhs)) {
5488    // The two types are different widths; if we are here, that
5489    // means the signed type is larger than the unsigned type, so
5490    // use the signed type.
5491    destType = lhsSigned ? lhs : rhs;
5492  } else {
5493    // The signed type is higher-ranked than the unsigned type,
5494    // but isn't actually any bigger (like unsigned int and long
5495    // on most 32-bit systems).  Use the unsigned type corresponding
5496    // to the signed type.
5497    destType = getCorrespondingUnsignedType(lhsSigned ? lhs : rhs);
5498  }
5499  return destType;
5500}
5501
5502GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
5503  GVALinkage External = GVA_StrongExternal;
5504
5505  Linkage L = FD->getLinkage();
5506  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5507      FD->getType()->getLinkage() == UniqueExternalLinkage)
5508    L = UniqueExternalLinkage;
5509
5510  switch (L) {
5511  case NoLinkage:
5512  case InternalLinkage:
5513  case UniqueExternalLinkage:
5514    return GVA_Internal;
5515
5516  case ExternalLinkage:
5517    switch (FD->getTemplateSpecializationKind()) {
5518    case TSK_Undeclared:
5519    case TSK_ExplicitSpecialization:
5520      External = GVA_StrongExternal;
5521      break;
5522
5523    case TSK_ExplicitInstantiationDefinition:
5524      return GVA_ExplicitTemplateInstantiation;
5525
5526    case TSK_ExplicitInstantiationDeclaration:
5527    case TSK_ImplicitInstantiation:
5528      External = GVA_TemplateInstantiation;
5529      break;
5530    }
5531  }
5532
5533  if (!FD->isInlined())
5534    return External;
5535
5536  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
5537    // GNU or C99 inline semantics. Determine whether this symbol should be
5538    // externally visible.
5539    if (FD->isInlineDefinitionExternallyVisible())
5540      return External;
5541
5542    // C99 inline semantics, where the symbol is not externally visible.
5543    return GVA_C99Inline;
5544  }
5545
5546  // C++0x [temp.explicit]p9:
5547  //   [ Note: The intent is that an inline function that is the subject of
5548  //   an explicit instantiation declaration will still be implicitly
5549  //   instantiated when used so that the body can be considered for
5550  //   inlining, but that no out-of-line copy of the inline function would be
5551  //   generated in the translation unit. -- end note ]
5552  if (FD->getTemplateSpecializationKind()
5553                                       == TSK_ExplicitInstantiationDeclaration)
5554    return GVA_C99Inline;
5555
5556  return GVA_CXXInline;
5557}
5558
5559GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
5560  // If this is a static data member, compute the kind of template
5561  // specialization. Otherwise, this variable is not part of a
5562  // template.
5563  TemplateSpecializationKind TSK = TSK_Undeclared;
5564  if (VD->isStaticDataMember())
5565    TSK = VD->getTemplateSpecializationKind();
5566
5567  Linkage L = VD->getLinkage();
5568  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5569      VD->getType()->getLinkage() == UniqueExternalLinkage)
5570    L = UniqueExternalLinkage;
5571
5572  switch (L) {
5573  case NoLinkage:
5574  case InternalLinkage:
5575  case UniqueExternalLinkage:
5576    return GVA_Internal;
5577
5578  case ExternalLinkage:
5579    switch (TSK) {
5580    case TSK_Undeclared:
5581    case TSK_ExplicitSpecialization:
5582      return GVA_StrongExternal;
5583
5584    case TSK_ExplicitInstantiationDeclaration:
5585      llvm_unreachable("Variable should not be instantiated");
5586      // Fall through to treat this like any other instantiation.
5587
5588    case TSK_ExplicitInstantiationDefinition:
5589      return GVA_ExplicitTemplateInstantiation;
5590
5591    case TSK_ImplicitInstantiation:
5592      return GVA_TemplateInstantiation;
5593    }
5594  }
5595
5596  return GVA_StrongExternal;
5597}
5598
5599bool ASTContext::DeclMustBeEmitted(const Decl *D) {
5600  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
5601    if (!VD->isFileVarDecl())
5602      return false;
5603  } else if (!isa<FunctionDecl>(D))
5604    return false;
5605
5606  // Weak references don't produce any output by themselves.
5607  if (D->hasAttr<WeakRefAttr>())
5608    return false;
5609
5610  // Aliases and used decls are required.
5611  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
5612    return true;
5613
5614  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
5615    // Forward declarations aren't required.
5616    if (!FD->isThisDeclarationADefinition())
5617      return false;
5618
5619    // Constructors and destructors are required.
5620    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
5621      return true;
5622
5623    // The key function for a class is required.
5624    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
5625      const CXXRecordDecl *RD = MD->getParent();
5626      if (MD->isOutOfLine() && RD->isDynamicClass()) {
5627        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
5628        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
5629          return true;
5630      }
5631    }
5632
5633    GVALinkage Linkage = GetGVALinkageForFunction(FD);
5634
5635    // static, static inline, always_inline, and extern inline functions can
5636    // always be deferred.  Normal inline functions can be deferred in C99/C++.
5637    // Implicit template instantiations can also be deferred in C++.
5638    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
5639        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
5640      return false;
5641    return true;
5642  }
5643
5644  const VarDecl *VD = cast<VarDecl>(D);
5645  assert(VD->isFileVarDecl() && "Expected file scoped var");
5646
5647  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
5648    return false;
5649
5650  // Structs that have non-trivial constructors or destructors are required.
5651
5652  // FIXME: Handle references.
5653  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
5654    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
5655      if (RD->hasDefinition() &&
5656          (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()))
5657        return true;
5658    }
5659  }
5660
5661  GVALinkage L = GetGVALinkageForVariable(VD);
5662  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
5663    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
5664      return false;
5665  }
5666
5667  return true;
5668}
5669
5670CXXABI::~CXXABI() {}
5671