ASTContext.cpp revision ed171b80e49c1ef3dcb9c2aa238cc50340ac6e90 
1//===--- ASTContext.cpp - Context to hold long-lived AST nodes ------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements the ASTContext interface.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/AST/ASTContext.h"
15#include "clang/AST/CharUnits.h"
16#include "clang/AST/DeclCXX.h"
17#include "clang/AST/DeclObjC.h"
18#include "clang/AST/DeclTemplate.h"
19#include "clang/AST/TypeLoc.h"
20#include "clang/AST/Expr.h"
21#include "clang/AST/ExprCXX.h"
22#include "clang/AST/ExternalASTSource.h"
23#include "clang/AST/ASTMutationListener.h"
24#include "clang/AST/RecordLayout.h"
25#include "clang/Basic/Builtins.h"
26#include "clang/Basic/SourceManager.h"
27#include "clang/Basic/TargetInfo.h"
28#include "llvm/ADT/SmallString.h"
29#include "llvm/ADT/StringExtras.h"
30#include "llvm/Support/MathExtras.h"
31#include "llvm/Support/raw_ostream.h"
32#include "CXXABI.h"
33
34using namespace clang;
35
36unsigned ASTContext::NumImplicitDefaultConstructors;
37unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
38unsigned ASTContext::NumImplicitCopyConstructors;
39unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
40unsigned ASTContext::NumImplicitCopyAssignmentOperators;
41unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
42unsigned ASTContext::NumImplicitDestructors;
43unsigned ASTContext::NumImplicitDestructorsDeclared;
44
45enum FloatingRank {
46  FloatRank, DoubleRank, LongDoubleRank
47};
48
49void
50ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
51                                               TemplateTemplateParmDecl *Parm) {
52  ID.AddInteger(Parm->getDepth());
53  ID.AddInteger(Parm->getPosition());
54  // FIXME: Parameter pack
55
56  TemplateParameterList *Params = Parm->getTemplateParameters();
57  ID.AddInteger(Params->size());
58  for (TemplateParameterList::const_iterator P = Params->begin(),
59                                          PEnd = Params->end();
60       P != PEnd; ++P) {
61    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
62      ID.AddInteger(0);
63      ID.AddBoolean(TTP->isParameterPack());
64      continue;
65    }
66
67    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
68      ID.AddInteger(1);
69      // FIXME: Parameter pack
70      ID.AddPointer(NTTP->getType().getAsOpaquePtr());
71      continue;
72    }
73
74    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
75    ID.AddInteger(2);
76    Profile(ID, TTP);
77  }
78}
79
80TemplateTemplateParmDecl *
81ASTContext::getCanonicalTemplateTemplateParmDecl(
82                                                 TemplateTemplateParmDecl *TTP) {
83  // Check if we already have a canonical template template parameter.
84  llvm::FoldingSetNodeID ID;
85  CanonicalTemplateTemplateParm::Profile(ID, TTP);
86  void *InsertPos = 0;
87  CanonicalTemplateTemplateParm *Canonical
88    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
89  if (Canonical)
90    return Canonical->getParam();
91
92  // Build a canonical template parameter list.
93  TemplateParameterList *Params = TTP->getTemplateParameters();
94  llvm::SmallVector<NamedDecl *, 4> CanonParams;
95  CanonParams.reserve(Params->size());
96  for (TemplateParameterList::const_iterator P = Params->begin(),
97                                          PEnd = Params->end();
98       P != PEnd; ++P) {
99    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
100      CanonParams.push_back(
101                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
102                                               SourceLocation(), TTP->getDepth(),
103                                               TTP->getIndex(), 0, false,
104                                               TTP->isParameterPack()));
105    else if (NonTypeTemplateParmDecl *NTTP
106             = dyn_cast<NonTypeTemplateParmDecl>(*P))
107      CanonParams.push_back(
108            NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
109                                            SourceLocation(), NTTP->getDepth(),
110                                            NTTP->getPosition(), 0,
111                                            getCanonicalType(NTTP->getType()),
112                                            0));
113    else
114      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
115                                           cast<TemplateTemplateParmDecl>(*P)));
116  }
117
118  TemplateTemplateParmDecl *CanonTTP
119    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
120                                       SourceLocation(), TTP->getDepth(),
121                                       TTP->getPosition(), 0,
122                         TemplateParameterList::Create(*this, SourceLocation(),
123                                                       SourceLocation(),
124                                                       CanonParams.data(),
125                                                       CanonParams.size(),
126                                                       SourceLocation()));
127
128  // Get the new insert position for the node we care about.
129  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
130  assert(Canonical == 0 && "Shouldn't be in the map!");
131  (void)Canonical;
132
133  // Create the canonical template template parameter entry.
134  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
135  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
136  return CanonTTP;
137}
138
139CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
140  if (!LangOpts.CPlusPlus) return 0;
141
142  switch (T.getCXXABI()) {
143  case CXXABI_ARM:
144    return CreateARMCXXABI(*this);
145  case CXXABI_Itanium:
146    return CreateItaniumCXXABI(*this);
147  case CXXABI_Microsoft:
148    return CreateMicrosoftCXXABI(*this);
149  }
150  return 0;
151}
152
153ASTContext::ASTContext(const LangOptions& LOpts, SourceManager &SM,
154                       const TargetInfo &t,
155                       IdentifierTable &idents, SelectorTable &sels,
156                       Builtin::Context &builtins,
157                       unsigned size_reserve) :
158  TemplateSpecializationTypes(this_()),
159  DependentTemplateSpecializationTypes(this_()),
160  GlobalNestedNameSpecifier(0), IsInt128Installed(false),
161  CFConstantStringTypeDecl(0), NSConstantStringTypeDecl(0),
162  ObjCFastEnumerationStateTypeDecl(0), FILEDecl(0), jmp_bufDecl(0),
163  sigjmp_bufDecl(0), BlockDescriptorType(0), BlockDescriptorExtendedType(0),
164  NullTypeSourceInfo(QualType()),
165  SourceMgr(SM), LangOpts(LOpts), ABI(createCXXABI(t)), Target(t),
166  Idents(idents), Selectors(sels),
167  BuiltinInfo(builtins),
168  DeclarationNames(*this),
169  ExternalSource(0), Listener(0), PrintingPolicy(LOpts),
170  LastSDM(0, 0),
171  UniqueBlockByRefTypeID(0), UniqueBlockParmTypeID(0) {
172  ObjCIdRedefinitionType = QualType();
173  ObjCClassRedefinitionType = QualType();
174  ObjCSelRedefinitionType = QualType();
175  if (size_reserve > 0) Types.reserve(size_reserve);
176  TUDecl = TranslationUnitDecl::Create(*this);
177  InitBuiltinTypes();
178}
179
180ASTContext::~ASTContext() {
181  // Release the DenseMaps associated with DeclContext objects.
182  // FIXME: Is this the ideal solution?
183  ReleaseDeclContextMaps();
184
185  // Call all of the deallocation functions.
186  for (unsigned I = 0, N = Deallocations.size(); I != N; ++I)
187    Deallocations[I].first(Deallocations[I].second);
188
189  // Release all of the memory associated with overridden C++ methods.
190  for (llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::iterator
191         OM = OverriddenMethods.begin(), OMEnd = OverriddenMethods.end();
192       OM != OMEnd; ++OM)
193    OM->second.Destroy();
194
195  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
196  // because they can contain DenseMaps.
197  for (llvm::DenseMap<const ObjCContainerDecl*,
198       const ASTRecordLayout*>::iterator
199       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
200    // Increment in loop to prevent using deallocated memory.
201    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
202      R->Destroy(*this);
203
204  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
205       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
206    // Increment in loop to prevent using deallocated memory.
207    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
208      R->Destroy(*this);
209  }
210
211  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
212                                                    AEnd = DeclAttrs.end();
213       A != AEnd; ++A)
214    A->second->~AttrVec();
215}
216
217void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
218  Deallocations.push_back(std::make_pair(Callback, Data));
219}
220
221void
222ASTContext::setExternalSource(llvm::OwningPtr<ExternalASTSource> &Source) {
223  ExternalSource.reset(Source.take());
224}
225
226void ASTContext::PrintStats() const {
227  fprintf(stderr, "*** AST Context Stats:\n");
228  fprintf(stderr, "  %d types total.\n", (int)Types.size());
229
230  unsigned counts[] = {
231#define TYPE(Name, Parent) 0,
232#define ABSTRACT_TYPE(Name, Parent)
233#include "clang/AST/TypeNodes.def"
234    0 // Extra
235  };
236
237  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
238    Type *T = Types[i];
239    counts[(unsigned)T->getTypeClass()]++;
240  }
241
242  unsigned Idx = 0;
243  unsigned TotalBytes = 0;
244#define TYPE(Name, Parent)                                              \
245  if (counts[Idx])                                                      \
246    fprintf(stderr, "    %d %s types\n", (int)counts[Idx], #Name);      \
247  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
248  ++Idx;
249#define ABSTRACT_TYPE(Name, Parent)
250#include "clang/AST/TypeNodes.def"
251
252  fprintf(stderr, "Total bytes = %d\n", int(TotalBytes));
253
254  // Implicit special member functions.
255  fprintf(stderr, "  %u/%u implicit default constructors created\n",
256          NumImplicitDefaultConstructorsDeclared,
257          NumImplicitDefaultConstructors);
258  fprintf(stderr, "  %u/%u implicit copy constructors created\n",
259          NumImplicitCopyConstructorsDeclared,
260          NumImplicitCopyConstructors);
261  fprintf(stderr, "  %u/%u implicit copy assignment operators created\n",
262          NumImplicitCopyAssignmentOperatorsDeclared,
263          NumImplicitCopyAssignmentOperators);
264  fprintf(stderr, "  %u/%u implicit destructors created\n",
265          NumImplicitDestructorsDeclared, NumImplicitDestructors);
266
267  if (ExternalSource.get()) {
268    fprintf(stderr, "\n");
269    ExternalSource->PrintStats();
270  }
271
272  BumpAlloc.PrintStats();
273}
274
275
276void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
277  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
278  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
279  Types.push_back(Ty);
280}
281
282void ASTContext::InitBuiltinTypes() {
283  assert(VoidTy.isNull() && "Context reinitialized?");
284
285  // C99 6.2.5p19.
286  InitBuiltinType(VoidTy,              BuiltinType::Void);
287
288  // C99 6.2.5p2.
289  InitBuiltinType(BoolTy,              BuiltinType::Bool);
290  // C99 6.2.5p3.
291  if (LangOpts.CharIsSigned)
292    InitBuiltinType(CharTy,            BuiltinType::Char_S);
293  else
294    InitBuiltinType(CharTy,            BuiltinType::Char_U);
295  // C99 6.2.5p4.
296  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
297  InitBuiltinType(ShortTy,             BuiltinType::Short);
298  InitBuiltinType(IntTy,               BuiltinType::Int);
299  InitBuiltinType(LongTy,              BuiltinType::Long);
300  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
301
302  // C99 6.2.5p6.
303  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
304  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
305  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
306  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
307  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
308
309  // C99 6.2.5p10.
310  InitBuiltinType(FloatTy,             BuiltinType::Float);
311  InitBuiltinType(DoubleTy,            BuiltinType::Double);
312  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
313
314  // GNU extension, 128-bit integers.
315  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
316  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
317
318  if (LangOpts.CPlusPlus) // C++ 3.9.1p5
319    InitBuiltinType(WCharTy,           BuiltinType::WChar);
320  else // C99
321    WCharTy = getFromTargetType(Target.getWCharType());
322
323  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
324    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
325  else // C99
326    Char16Ty = getFromTargetType(Target.getChar16Type());
327
328  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
329    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
330  else // C99
331    Char32Ty = getFromTargetType(Target.getChar32Type());
332
333  // Placeholder type for type-dependent expressions whose type is
334  // completely unknown. No code should ever check a type against
335  // DependentTy and users should never see it; however, it is here to
336  // help diagnose failures to properly check for type-dependent
337  // expressions.
338  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
339
340  // Placeholder type for functions.
341  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
342
343  // Placeholder type for C++0x auto declarations whose real type has
344  // not yet been deduced.
345  InitBuiltinType(UndeducedAutoTy,     BuiltinType::UndeducedAuto);
346
347  // C99 6.2.5p11.
348  FloatComplexTy      = getComplexType(FloatTy);
349  DoubleComplexTy     = getComplexType(DoubleTy);
350  LongDoubleComplexTy = getComplexType(LongDoubleTy);
351
352  BuiltinVaListType = QualType();
353
354  // "Builtin" typedefs set by Sema::ActOnTranslationUnitScope().
355  ObjCIdTypedefType = QualType();
356  ObjCClassTypedefType = QualType();
357  ObjCSelTypedefType = QualType();
358
359  // Builtin types for 'id', 'Class', and 'SEL'.
360  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
361  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
362  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
363
364  ObjCConstantStringType = QualType();
365
366  // void * type
367  VoidPtrTy = getPointerType(VoidTy);
368
369  // nullptr type (C++0x 2.14.7)
370  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
371}
372
373Diagnostic &ASTContext::getDiagnostics() const {
374  return SourceMgr.getDiagnostics();
375}
376
377AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
378  AttrVec *&Result = DeclAttrs[D];
379  if (!Result) {
380    void *Mem = Allocate(sizeof(AttrVec));
381    Result = new (Mem) AttrVec;
382  }
383
384  return *Result;
385}
386
387/// \brief Erase the attributes corresponding to the given declaration.
388void ASTContext::eraseDeclAttrs(const Decl *D) {
389  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
390  if (Pos != DeclAttrs.end()) {
391    Pos->second->~AttrVec();
392    DeclAttrs.erase(Pos);
393  }
394}
395
396
397MemberSpecializationInfo *
398ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
399  assert(Var->isStaticDataMember() && "Not a static data member");
400  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
401    = InstantiatedFromStaticDataMember.find(Var);
402  if (Pos == InstantiatedFromStaticDataMember.end())
403    return 0;
404
405  return Pos->second;
406}
407
408void
409ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
410                                                TemplateSpecializationKind TSK,
411                                          SourceLocation PointOfInstantiation) {
412  assert(Inst->isStaticDataMember() && "Not a static data member");
413  assert(Tmpl->isStaticDataMember() && "Not a static data member");
414  assert(!InstantiatedFromStaticDataMember[Inst] &&
415         "Already noted what static data member was instantiated from");
416  InstantiatedFromStaticDataMember[Inst]
417    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
418}
419
420NamedDecl *
421ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
422  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
423    = InstantiatedFromUsingDecl.find(UUD);
424  if (Pos == InstantiatedFromUsingDecl.end())
425    return 0;
426
427  return Pos->second;
428}
429
430void
431ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
432  assert((isa<UsingDecl>(Pattern) ||
433          isa<UnresolvedUsingValueDecl>(Pattern) ||
434          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
435         "pattern decl is not a using decl");
436  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
437  InstantiatedFromUsingDecl[Inst] = Pattern;
438}
439
440UsingShadowDecl *
441ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
442  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
443    = InstantiatedFromUsingShadowDecl.find(Inst);
444  if (Pos == InstantiatedFromUsingShadowDecl.end())
445    return 0;
446
447  return Pos->second;
448}
449
450void
451ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
452                                               UsingShadowDecl *Pattern) {
453  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
454  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
455}
456
457FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
458  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
459    = InstantiatedFromUnnamedFieldDecl.find(Field);
460  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
461    return 0;
462
463  return Pos->second;
464}
465
466void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
467                                                     FieldDecl *Tmpl) {
468  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
469  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
470  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
471         "Already noted what unnamed field was instantiated from");
472
473  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
474}
475
476ASTContext::overridden_cxx_method_iterator
477ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
478  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
479    = OverriddenMethods.find(Method);
480  if (Pos == OverriddenMethods.end())
481    return 0;
482
483  return Pos->second.begin();
484}
485
486ASTContext::overridden_cxx_method_iterator
487ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
488  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
489    = OverriddenMethods.find(Method);
490  if (Pos == OverriddenMethods.end())
491    return 0;
492
493  return Pos->second.end();
494}
495
496unsigned
497ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
498  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
499    = OverriddenMethods.find(Method);
500  if (Pos == OverriddenMethods.end())
501    return 0;
502
503  return Pos->second.size();
504}
505
506void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
507                                     const CXXMethodDecl *Overridden) {
508  OverriddenMethods[Method].push_back(Overridden);
509}
510
511//===----------------------------------------------------------------------===//
512//                         Type Sizing and Analysis
513//===----------------------------------------------------------------------===//
514
515/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
516/// scalar floating point type.
517const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
518  const BuiltinType *BT = T->getAs<BuiltinType>();
519  assert(BT && "Not a floating point type!");
520  switch (BT->getKind()) {
521  default: assert(0 && "Not a floating point type!");
522  case BuiltinType::Float:      return Target.getFloatFormat();
523  case BuiltinType::Double:     return Target.getDoubleFormat();
524  case BuiltinType::LongDouble: return Target.getLongDoubleFormat();
525  }
526}
527
528/// getDeclAlign - Return a conservative estimate of the alignment of the
529/// specified decl.  Note that bitfields do not have a valid alignment, so
530/// this method will assert on them.
531/// If @p RefAsPointee, references are treated like their underlying type
532/// (for alignof), else they're treated like pointers (for CodeGen).
533CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) {
534  unsigned Align = Target.getCharWidth();
535
536  bool UseAlignAttrOnly = false;
537  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
538    Align = AlignFromAttr;
539
540    // __attribute__((aligned)) can increase or decrease alignment
541    // *except* on a struct or struct member, where it only increases
542    // alignment unless 'packed' is also specified.
543    //
544    // It is an error for [[align]] to decrease alignment, so we can
545    // ignore that possibility;  Sema should diagnose it.
546    if (isa<FieldDecl>(D)) {
547      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
548        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
549    } else {
550      UseAlignAttrOnly = true;
551    }
552  }
553
554  if (UseAlignAttrOnly) {
555    // ignore type of value
556  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
557    QualType T = VD->getType();
558    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
559      if (RefAsPointee)
560        T = RT->getPointeeType();
561      else
562        T = getPointerType(RT->getPointeeType());
563    }
564    if (!T->isIncompleteType() && !T->isFunctionType()) {
565      unsigned MinWidth = Target.getLargeArrayMinWidth();
566      unsigned ArrayAlign = Target.getLargeArrayAlign();
567      if (isa<VariableArrayType>(T) && MinWidth != 0)
568        Align = std::max(Align, ArrayAlign);
569      if (ConstantArrayType *CT = dyn_cast<ConstantArrayType>(T)) {
570        unsigned Size = getTypeSize(CT);
571        if (MinWidth != 0 && MinWidth <= Size)
572          Align = std::max(Align, ArrayAlign);
573      }
574      // Incomplete or function types default to 1.
575      while (isa<VariableArrayType>(T) || isa<IncompleteArrayType>(T))
576        T = cast<ArrayType>(T)->getElementType();
577
578      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
579    }
580    if (const FieldDecl *FD = dyn_cast<FieldDecl>(VD)) {
581      // In the case of a field in a packed struct, we want the minimum
582      // of the alignment of the field and the alignment of the struct.
583      Align = std::min(Align,
584        getPreferredTypeAlign(FD->getParent()->getTypeForDecl()));
585    }
586  }
587
588  return CharUnits::fromQuantity(Align / Target.getCharWidth());
589}
590
591std::pair<CharUnits, CharUnits>
592ASTContext::getTypeInfoInChars(const Type *T) {
593  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
594  return std::make_pair(CharUnits::fromQuantity(Info.first / getCharWidth()),
595                        CharUnits::fromQuantity(Info.second / getCharWidth()));
596}
597
598std::pair<CharUnits, CharUnits>
599ASTContext::getTypeInfoInChars(QualType T) {
600  return getTypeInfoInChars(T.getTypePtr());
601}
602
603/// getTypeSize - Return the size of the specified type, in bits.  This method
604/// does not work on incomplete types.
605///
606/// FIXME: Pointers into different addr spaces could have different sizes and
607/// alignment requirements: getPointerInfo should take an AddrSpace, this
608/// should take a QualType, &c.
609std::pair<uint64_t, unsigned>
610ASTContext::getTypeInfo(const Type *T) {
611  uint64_t Width=0;
612  unsigned Align=8;
613  switch (T->getTypeClass()) {
614#define TYPE(Class, Base)
615#define ABSTRACT_TYPE(Class, Base)
616#define NON_CANONICAL_TYPE(Class, Base)
617#define DEPENDENT_TYPE(Class, Base) case Type::Class:
618#include "clang/AST/TypeNodes.def"
619    assert(false && "Should not see dependent types");
620    break;
621
622  case Type::FunctionNoProto:
623  case Type::FunctionProto:
624    // GCC extension: alignof(function) = 32 bits
625    Width = 0;
626    Align = 32;
627    break;
628
629  case Type::IncompleteArray:
630  case Type::VariableArray:
631    Width = 0;
632    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
633    break;
634
635  case Type::ConstantArray: {
636    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
637
638    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
639    Width = EltInfo.first*CAT->getSize().getZExtValue();
640    Align = EltInfo.second;
641    break;
642  }
643  case Type::ExtVector:
644  case Type::Vector: {
645    const VectorType *VT = cast<VectorType>(T);
646    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
647    Width = EltInfo.first*VT->getNumElements();
648    Align = Width;
649    // If the alignment is not a power of 2, round up to the next power of 2.
650    // This happens for non-power-of-2 length vectors.
651    if (Align & (Align-1)) {
652      Align = llvm::NextPowerOf2(Align);
653      Width = llvm::RoundUpToAlignment(Width, Align);
654    }
655    break;
656  }
657
658  case Type::Builtin:
659    switch (cast<BuiltinType>(T)->getKind()) {
660    default: assert(0 && "Unknown builtin type!");
661    case BuiltinType::Void:
662      // GCC extension: alignof(void) = 8 bits.
663      Width = 0;
664      Align = 8;
665      break;
666
667    case BuiltinType::Bool:
668      Width = Target.getBoolWidth();
669      Align = Target.getBoolAlign();
670      break;
671    case BuiltinType::Char_S:
672    case BuiltinType::Char_U:
673    case BuiltinType::UChar:
674    case BuiltinType::SChar:
675      Width = Target.getCharWidth();
676      Align = Target.getCharAlign();
677      break;
678    case BuiltinType::WChar:
679      Width = Target.getWCharWidth();
680      Align = Target.getWCharAlign();
681      break;
682    case BuiltinType::Char16:
683      Width = Target.getChar16Width();
684      Align = Target.getChar16Align();
685      break;
686    case BuiltinType::Char32:
687      Width = Target.getChar32Width();
688      Align = Target.getChar32Align();
689      break;
690    case BuiltinType::UShort:
691    case BuiltinType::Short:
692      Width = Target.getShortWidth();
693      Align = Target.getShortAlign();
694      break;
695    case BuiltinType::UInt:
696    case BuiltinType::Int:
697      Width = Target.getIntWidth();
698      Align = Target.getIntAlign();
699      break;
700    case BuiltinType::ULong:
701    case BuiltinType::Long:
702      Width = Target.getLongWidth();
703      Align = Target.getLongAlign();
704      break;
705    case BuiltinType::ULongLong:
706    case BuiltinType::LongLong:
707      Width = Target.getLongLongWidth();
708      Align = Target.getLongLongAlign();
709      break;
710    case BuiltinType::Int128:
711    case BuiltinType::UInt128:
712      Width = 128;
713      Align = 128; // int128_t is 128-bit aligned on all targets.
714      break;
715    case BuiltinType::Float:
716      Width = Target.getFloatWidth();
717      Align = Target.getFloatAlign();
718      break;
719    case BuiltinType::Double:
720      Width = Target.getDoubleWidth();
721      Align = Target.getDoubleAlign();
722      break;
723    case BuiltinType::LongDouble:
724      Width = Target.getLongDoubleWidth();
725      Align = Target.getLongDoubleAlign();
726      break;
727    case BuiltinType::NullPtr:
728      Width = Target.getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
729      Align = Target.getPointerAlign(0); //   == sizeof(void*)
730      break;
731    case BuiltinType::ObjCId:
732    case BuiltinType::ObjCClass:
733    case BuiltinType::ObjCSel:
734      Width = Target.getPointerWidth(0);
735      Align = Target.getPointerAlign(0);
736      break;
737    }
738    break;
739  case Type::ObjCObjectPointer:
740    Width = Target.getPointerWidth(0);
741    Align = Target.getPointerAlign(0);
742    break;
743  case Type::BlockPointer: {
744    unsigned AS = cast<BlockPointerType>(T)->getPointeeType().getAddressSpace();
745    Width = Target.getPointerWidth(AS);
746    Align = Target.getPointerAlign(AS);
747    break;
748  }
749  case Type::LValueReference:
750  case Type::RValueReference: {
751    // alignof and sizeof should never enter this code path here, so we go
752    // the pointer route.
753    unsigned AS = cast<ReferenceType>(T)->getPointeeType().getAddressSpace();
754    Width = Target.getPointerWidth(AS);
755    Align = Target.getPointerAlign(AS);
756    break;
757  }
758  case Type::Pointer: {
759    unsigned AS = cast<PointerType>(T)->getPointeeType().getAddressSpace();
760    Width = Target.getPointerWidth(AS);
761    Align = Target.getPointerAlign(AS);
762    break;
763  }
764  case Type::MemberPointer: {
765    const MemberPointerType *MPT = cast<MemberPointerType>(T);
766    std::pair<uint64_t, unsigned> PtrDiffInfo =
767      getTypeInfo(getPointerDiffType());
768    Width = PtrDiffInfo.first * ABI->getMemberPointerSize(MPT);
769    Align = PtrDiffInfo.second;
770    break;
771  }
772  case Type::Complex: {
773    // Complex types have the same alignment as their elements, but twice the
774    // size.
775    std::pair<uint64_t, unsigned> EltInfo =
776      getTypeInfo(cast<ComplexType>(T)->getElementType());
777    Width = EltInfo.first*2;
778    Align = EltInfo.second;
779    break;
780  }
781  case Type::ObjCObject:
782    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
783  case Type::ObjCInterface: {
784    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
785    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
786    Width = Layout.getSize();
787    Align = Layout.getAlignment();
788    break;
789  }
790  case Type::Record:
791  case Type::Enum: {
792    const TagType *TT = cast<TagType>(T);
793
794    if (TT->getDecl()->isInvalidDecl()) {
795      Width = 1;
796      Align = 1;
797      break;
798    }
799
800    if (const EnumType *ET = dyn_cast<EnumType>(TT))
801      return getTypeInfo(ET->getDecl()->getIntegerType());
802
803    const RecordType *RT = cast<RecordType>(TT);
804    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
805    Width = Layout.getSize();
806    Align = Layout.getAlignment();
807    break;
808  }
809
810  case Type::SubstTemplateTypeParm:
811    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
812                       getReplacementType().getTypePtr());
813
814  case Type::Typedef: {
815    const TypedefDecl *Typedef = cast<TypedefType>(T)->getDecl();
816    std::pair<uint64_t, unsigned> Info
817      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
818    Align = std::max(Typedef->getMaxAlignment(), Info.second);
819    Width = Info.first;
820    break;
821  }
822
823  case Type::TypeOfExpr:
824    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
825                         .getTypePtr());
826
827  case Type::TypeOf:
828    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
829
830  case Type::Decltype:
831    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
832                        .getTypePtr());
833
834  case Type::Elaborated:
835    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
836
837  case Type::TemplateSpecialization:
838    assert(getCanonicalType(T) != T &&
839           "Cannot request the size of a dependent type");
840    // FIXME: this is likely to be wrong once we support template
841    // aliases, since a template alias could refer to a typedef that
842    // has an __aligned__ attribute on it.
843    return getTypeInfo(getCanonicalType(T));
844  }
845
846  assert(Align && (Align & (Align-1)) == 0 && "Alignment must be power of 2");
847  return std::make_pair(Width, Align);
848}
849
850/// getTypeSizeInChars - Return the size of the specified type, in characters.
851/// This method does not work on incomplete types.
852CharUnits ASTContext::getTypeSizeInChars(QualType T) {
853  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
854}
855CharUnits ASTContext::getTypeSizeInChars(const Type *T) {
856  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
857}
858
859/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
860/// characters. This method does not work on incomplete types.
861CharUnits ASTContext::getTypeAlignInChars(QualType T) {
862  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
863}
864CharUnits ASTContext::getTypeAlignInChars(const Type *T) {
865  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
866}
867
868/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
869/// type for the current target in bits.  This can be different than the ABI
870/// alignment in cases where it is beneficial for performance to overalign
871/// a data type.
872unsigned ASTContext::getPreferredTypeAlign(const Type *T) {
873  unsigned ABIAlign = getTypeAlign(T);
874
875  // Double and long long should be naturally aligned if possible.
876  if (const ComplexType* CT = T->getAs<ComplexType>())
877    T = CT->getElementType().getTypePtr();
878  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
879      T->isSpecificBuiltinType(BuiltinType::LongLong))
880    return std::max(ABIAlign, (unsigned)getTypeSize(T));
881
882  return ABIAlign;
883}
884
885/// ShallowCollectObjCIvars -
886/// Collect all ivars, including those synthesized, in the current class.
887///
888void ASTContext::ShallowCollectObjCIvars(const ObjCInterfaceDecl *OI,
889                                 llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
890  // FIXME. This need be removed but there are two many places which
891  // assume const-ness of ObjCInterfaceDecl
892  ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
893  for (ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
894        Iv= Iv->getNextIvar())
895    Ivars.push_back(Iv);
896}
897
898/// DeepCollectObjCIvars -
899/// This routine first collects all declared, but not synthesized, ivars in
900/// super class and then collects all ivars, including those synthesized for
901/// current class. This routine is used for implementation of current class
902/// when all ivars, declared and synthesized are known.
903///
904void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
905                                      bool leafClass,
906                                llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
907  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
908    DeepCollectObjCIvars(SuperClass, false, Ivars);
909  if (!leafClass) {
910    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
911         E = OI->ivar_end(); I != E; ++I)
912      Ivars.push_back(*I);
913  }
914  else
915    ShallowCollectObjCIvars(OI, Ivars);
916}
917
918/// CollectInheritedProtocols - Collect all protocols in current class and
919/// those inherited by it.
920void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
921                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
922  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
923    // We can use protocol_iterator here instead of
924    // all_referenced_protocol_iterator since we are walking all categories.
925    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
926         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
927      ObjCProtocolDecl *Proto = (*P);
928      Protocols.insert(Proto);
929      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
930           PE = Proto->protocol_end(); P != PE; ++P) {
931        Protocols.insert(*P);
932        CollectInheritedProtocols(*P, Protocols);
933      }
934    }
935
936    // Categories of this Interface.
937    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
938         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
939      CollectInheritedProtocols(CDeclChain, Protocols);
940    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
941      while (SD) {
942        CollectInheritedProtocols(SD, Protocols);
943        SD = SD->getSuperClass();
944      }
945  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
946    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
947         PE = OC->protocol_end(); P != PE; ++P) {
948      ObjCProtocolDecl *Proto = (*P);
949      Protocols.insert(Proto);
950      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
951           PE = Proto->protocol_end(); P != PE; ++P)
952        CollectInheritedProtocols(*P, Protocols);
953    }
954  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
955    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
956         PE = OP->protocol_end(); P != PE; ++P) {
957      ObjCProtocolDecl *Proto = (*P);
958      Protocols.insert(Proto);
959      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
960           PE = Proto->protocol_end(); P != PE; ++P)
961        CollectInheritedProtocols(*P, Protocols);
962    }
963  }
964}
965
966unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) {
967  unsigned count = 0;
968  // Count ivars declared in class extension.
969  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
970       CDecl = CDecl->getNextClassExtension())
971    count += CDecl->ivar_size();
972
973  // Count ivar defined in this class's implementation.  This
974  // includes synthesized ivars.
975  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
976    count += ImplDecl->ivar_size();
977
978  return count;
979}
980
981/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
982ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
983  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
984    I = ObjCImpls.find(D);
985  if (I != ObjCImpls.end())
986    return cast<ObjCImplementationDecl>(I->second);
987  return 0;
988}
989/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
990ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
991  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
992    I = ObjCImpls.find(D);
993  if (I != ObjCImpls.end())
994    return cast<ObjCCategoryImplDecl>(I->second);
995  return 0;
996}
997
998/// \brief Set the implementation of ObjCInterfaceDecl.
999void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1000                           ObjCImplementationDecl *ImplD) {
1001  assert(IFaceD && ImplD && "Passed null params");
1002  ObjCImpls[IFaceD] = ImplD;
1003}
1004/// \brief Set the implementation of ObjCCategoryDecl.
1005void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1006                           ObjCCategoryImplDecl *ImplD) {
1007  assert(CatD && ImplD && "Passed null params");
1008  ObjCImpls[CatD] = ImplD;
1009}
1010
1011/// \brief Allocate an uninitialized TypeSourceInfo.
1012///
1013/// The caller should initialize the memory held by TypeSourceInfo using
1014/// the TypeLoc wrappers.
1015///
1016/// \param T the type that will be the basis for type source info. This type
1017/// should refer to how the declarator was written in source code, not to
1018/// what type semantic analysis resolved the declarator to.
1019TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1020                                                 unsigned DataSize) {
1021  if (!DataSize)
1022    DataSize = TypeLoc::getFullDataSizeForType(T);
1023  else
1024    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1025           "incorrect data size provided to CreateTypeSourceInfo!");
1026
1027  TypeSourceInfo *TInfo =
1028    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1029  new (TInfo) TypeSourceInfo(T);
1030  return TInfo;
1031}
1032
1033TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1034                                                     SourceLocation L) {
1035  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1036  DI->getTypeLoc().initialize(L);
1037  return DI;
1038}
1039
1040const ASTRecordLayout &
1041ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) {
1042  return getObjCLayout(D, 0);
1043}
1044
1045const ASTRecordLayout &
1046ASTContext::getASTObjCImplementationLayout(const ObjCImplementationDecl *D) {
1047  return getObjCLayout(D->getClassInterface(), D);
1048}
1049
1050//===----------------------------------------------------------------------===//
1051//                   Type creation/memoization methods
1052//===----------------------------------------------------------------------===//
1053
1054QualType ASTContext::getExtQualType(const Type *TypeNode, Qualifiers Quals) {
1055  unsigned Fast = Quals.getFastQualifiers();
1056  Quals.removeFastQualifiers();
1057
1058  // Check if we've already instantiated this type.
1059  llvm::FoldingSetNodeID ID;
1060  ExtQuals::Profile(ID, TypeNode, Quals);
1061  void *InsertPos = 0;
1062  if (ExtQuals *EQ = ExtQualNodes.FindNodeOrInsertPos(ID, InsertPos)) {
1063    assert(EQ->getQualifiers() == Quals);
1064    QualType T = QualType(EQ, Fast);
1065    return T;
1066  }
1067
1068  ExtQuals *New = new (*this, TypeAlignment) ExtQuals(*this, TypeNode, Quals);
1069  ExtQualNodes.InsertNode(New, InsertPos);
1070  QualType T = QualType(New, Fast);
1071  return T;
1072}
1073
1074QualType ASTContext::getVolatileType(QualType T) {
1075  QualType CanT = getCanonicalType(T);
1076  if (CanT.isVolatileQualified()) return T;
1077
1078  QualifierCollector Quals;
1079  const Type *TypeNode = Quals.strip(T);
1080  Quals.addVolatile();
1081
1082  return getExtQualType(TypeNode, Quals);
1083}
1084
1085QualType ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) {
1086  QualType CanT = getCanonicalType(T);
1087  if (CanT.getAddressSpace() == AddressSpace)
1088    return T;
1089
1090  // If we are composing extended qualifiers together, merge together
1091  // into one ExtQuals node.
1092  QualifierCollector Quals;
1093  const Type *TypeNode = Quals.strip(T);
1094
1095  // If this type already has an address space specified, it cannot get
1096  // another one.
1097  assert(!Quals.hasAddressSpace() &&
1098         "Type cannot be in multiple addr spaces!");
1099  Quals.addAddressSpace(AddressSpace);
1100
1101  return getExtQualType(TypeNode, Quals);
1102}
1103
1104QualType ASTContext::getObjCGCQualType(QualType T,
1105                                       Qualifiers::GC GCAttr) {
1106  QualType CanT = getCanonicalType(T);
1107  if (CanT.getObjCGCAttr() == GCAttr)
1108    return T;
1109
1110  if (T->isPointerType()) {
1111    QualType Pointee = T->getAs<PointerType>()->getPointeeType();
1112    if (Pointee->isAnyPointerType()) {
1113      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1114      return getPointerType(ResultType);
1115    }
1116  }
1117
1118  // If we are composing extended qualifiers together, merge together
1119  // into one ExtQuals node.
1120  QualifierCollector Quals;
1121  const Type *TypeNode = Quals.strip(T);
1122
1123  // If this type already has an ObjCGC specified, it cannot get
1124  // another one.
1125  assert(!Quals.hasObjCGCAttr() &&
1126         "Type cannot have multiple ObjCGCs!");
1127  Quals.addObjCGCAttr(GCAttr);
1128
1129  return getExtQualType(TypeNode, Quals);
1130}
1131
1132static QualType getExtFunctionType(ASTContext& Context, QualType T,
1133                                        const FunctionType::ExtInfo &Info) {
1134  QualType ResultType;
1135  if (const PointerType *Pointer = T->getAs<PointerType>()) {
1136    QualType Pointee = Pointer->getPointeeType();
1137    ResultType = getExtFunctionType(Context, Pointee, Info);
1138    if (ResultType == Pointee)
1139      return T;
1140
1141    ResultType = Context.getPointerType(ResultType);
1142  } else if (const BlockPointerType *BlockPointer
1143                                              = T->getAs<BlockPointerType>()) {
1144    QualType Pointee = BlockPointer->getPointeeType();
1145    ResultType = getExtFunctionType(Context, Pointee, Info);
1146    if (ResultType == Pointee)
1147      return T;
1148
1149    ResultType = Context.getBlockPointerType(ResultType);
1150  } else if (const MemberPointerType *MemberPointer
1151                                            = T->getAs<MemberPointerType>()) {
1152    QualType Pointee = MemberPointer->getPointeeType();
1153    ResultType = getExtFunctionType(Context, Pointee, Info);
1154    if (ResultType == Pointee)
1155      return T;
1156
1157    ResultType = Context.getMemberPointerType(ResultType,
1158                                              MemberPointer->getClass());
1159   } else if (const FunctionType *F = T->getAs<FunctionType>()) {
1160    if (F->getExtInfo() == Info)
1161      return T;
1162
1163    if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(F)) {
1164      ResultType = Context.getFunctionNoProtoType(FNPT->getResultType(),
1165                                                  Info);
1166    } else {
1167      const FunctionProtoType *FPT = cast<FunctionProtoType>(F);
1168      ResultType
1169        = Context.getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1170                                  FPT->getNumArgs(), FPT->isVariadic(),
1171                                  FPT->getTypeQuals(),
1172                                  FPT->hasExceptionSpec(),
1173                                  FPT->hasAnyExceptionSpec(),
1174                                  FPT->getNumExceptions(),
1175                                  FPT->exception_begin(),
1176                                  Info);
1177    }
1178  } else
1179    return T;
1180
1181  return Context.getQualifiedType(ResultType, T.getLocalQualifiers());
1182}
1183
1184QualType ASTContext::getNoReturnType(QualType T, bool AddNoReturn) {
1185  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1186  return getExtFunctionType(*this, T,
1187                                 Info.withNoReturn(AddNoReturn));
1188}
1189
1190QualType ASTContext::getCallConvType(QualType T, CallingConv CallConv) {
1191  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1192  return getExtFunctionType(*this, T,
1193                            Info.withCallingConv(CallConv));
1194}
1195
1196QualType ASTContext::getRegParmType(QualType T, unsigned RegParm) {
1197  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1198  return getExtFunctionType(*this, T,
1199                                 Info.withRegParm(RegParm));
1200}
1201
1202/// getComplexType - Return the uniqued reference to the type for a complex
1203/// number with the specified element type.
1204QualType ASTContext::getComplexType(QualType T) {
1205  // Unique pointers, to guarantee there is only one pointer of a particular
1206  // structure.
1207  llvm::FoldingSetNodeID ID;
1208  ComplexType::Profile(ID, T);
1209
1210  void *InsertPos = 0;
1211  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1212    return QualType(CT, 0);
1213
1214  // If the pointee type isn't canonical, this won't be a canonical type either,
1215  // so fill in the canonical type field.
1216  QualType Canonical;
1217  if (!T.isCanonical()) {
1218    Canonical = getComplexType(getCanonicalType(T));
1219
1220    // Get the new insert position for the node we care about.
1221    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1222    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1223  }
1224  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1225  Types.push_back(New);
1226  ComplexTypes.InsertNode(New, InsertPos);
1227  return QualType(New, 0);
1228}
1229
1230/// getPointerType - Return the uniqued reference to the type for a pointer to
1231/// the specified type.
1232QualType ASTContext::getPointerType(QualType T) {
1233  // Unique pointers, to guarantee there is only one pointer of a particular
1234  // structure.
1235  llvm::FoldingSetNodeID ID;
1236  PointerType::Profile(ID, T);
1237
1238  void *InsertPos = 0;
1239  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1240    return QualType(PT, 0);
1241
1242  // If the pointee type isn't canonical, this won't be a canonical type either,
1243  // so fill in the canonical type field.
1244  QualType Canonical;
1245  if (!T.isCanonical()) {
1246    Canonical = getPointerType(getCanonicalType(T));
1247
1248    // Get the new insert position for the node we care about.
1249    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1250    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1251  }
1252  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1253  Types.push_back(New);
1254  PointerTypes.InsertNode(New, InsertPos);
1255  return QualType(New, 0);
1256}
1257
1258/// getBlockPointerType - Return the uniqued reference to the type for
1259/// a pointer to the specified block.
1260QualType ASTContext::getBlockPointerType(QualType T) {
1261  assert(T->isFunctionType() && "block of function types only");
1262  // Unique pointers, to guarantee there is only one block of a particular
1263  // structure.
1264  llvm::FoldingSetNodeID ID;
1265  BlockPointerType::Profile(ID, T);
1266
1267  void *InsertPos = 0;
1268  if (BlockPointerType *PT =
1269        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1270    return QualType(PT, 0);
1271
1272  // If the block pointee type isn't canonical, this won't be a canonical
1273  // type either so fill in the canonical type field.
1274  QualType Canonical;
1275  if (!T.isCanonical()) {
1276    Canonical = getBlockPointerType(getCanonicalType(T));
1277
1278    // Get the new insert position for the node we care about.
1279    BlockPointerType *NewIP =
1280      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1281    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1282  }
1283  BlockPointerType *New
1284    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1285  Types.push_back(New);
1286  BlockPointerTypes.InsertNode(New, InsertPos);
1287  return QualType(New, 0);
1288}
1289
1290/// getLValueReferenceType - Return the uniqued reference to the type for an
1291/// lvalue reference to the specified type.
1292QualType ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) {
1293  // Unique pointers, to guarantee there is only one pointer of a particular
1294  // structure.
1295  llvm::FoldingSetNodeID ID;
1296  ReferenceType::Profile(ID, T, SpelledAsLValue);
1297
1298  void *InsertPos = 0;
1299  if (LValueReferenceType *RT =
1300        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1301    return QualType(RT, 0);
1302
1303  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1304
1305  // If the referencee type isn't canonical, this won't be a canonical type
1306  // either, so fill in the canonical type field.
1307  QualType Canonical;
1308  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1309    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1310    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1311
1312    // Get the new insert position for the node we care about.
1313    LValueReferenceType *NewIP =
1314      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1315    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1316  }
1317
1318  LValueReferenceType *New
1319    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1320                                                     SpelledAsLValue);
1321  Types.push_back(New);
1322  LValueReferenceTypes.InsertNode(New, InsertPos);
1323
1324  return QualType(New, 0);
1325}
1326
1327/// getRValueReferenceType - Return the uniqued reference to the type for an
1328/// rvalue reference to the specified type.
1329QualType ASTContext::getRValueReferenceType(QualType T) {
1330  // Unique pointers, to guarantee there is only one pointer of a particular
1331  // structure.
1332  llvm::FoldingSetNodeID ID;
1333  ReferenceType::Profile(ID, T, false);
1334
1335  void *InsertPos = 0;
1336  if (RValueReferenceType *RT =
1337        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1338    return QualType(RT, 0);
1339
1340  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1341
1342  // If the referencee type isn't canonical, this won't be a canonical type
1343  // either, so fill in the canonical type field.
1344  QualType Canonical;
1345  if (InnerRef || !T.isCanonical()) {
1346    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1347    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1348
1349    // Get the new insert position for the node we care about.
1350    RValueReferenceType *NewIP =
1351      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1352    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1353  }
1354
1355  RValueReferenceType *New
1356    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1357  Types.push_back(New);
1358  RValueReferenceTypes.InsertNode(New, InsertPos);
1359  return QualType(New, 0);
1360}
1361
1362/// getMemberPointerType - Return the uniqued reference to the type for a
1363/// member pointer to the specified type, in the specified class.
1364QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) {
1365  // Unique pointers, to guarantee there is only one pointer of a particular
1366  // structure.
1367  llvm::FoldingSetNodeID ID;
1368  MemberPointerType::Profile(ID, T, Cls);
1369
1370  void *InsertPos = 0;
1371  if (MemberPointerType *PT =
1372      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1373    return QualType(PT, 0);
1374
1375  // If the pointee or class type isn't canonical, this won't be a canonical
1376  // type either, so fill in the canonical type field.
1377  QualType Canonical;
1378  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1379    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1380
1381    // Get the new insert position for the node we care about.
1382    MemberPointerType *NewIP =
1383      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1384    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1385  }
1386  MemberPointerType *New
1387    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1388  Types.push_back(New);
1389  MemberPointerTypes.InsertNode(New, InsertPos);
1390  return QualType(New, 0);
1391}
1392
1393/// getConstantArrayType - Return the unique reference to the type for an
1394/// array of the specified element type.
1395QualType ASTContext::getConstantArrayType(QualType EltTy,
1396                                          const llvm::APInt &ArySizeIn,
1397                                          ArrayType::ArraySizeModifier ASM,
1398                                          unsigned EltTypeQuals) {
1399  assert((EltTy->isDependentType() ||
1400          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1401         "Constant array of VLAs is illegal!");
1402
1403  // Convert the array size into a canonical width matching the pointer size for
1404  // the target.
1405  llvm::APInt ArySize(ArySizeIn);
1406  ArySize.zextOrTrunc(Target.getPointerWidth(EltTy.getAddressSpace()));
1407
1408  llvm::FoldingSetNodeID ID;
1409  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, EltTypeQuals);
1410
1411  void *InsertPos = 0;
1412  if (ConstantArrayType *ATP =
1413      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1414    return QualType(ATP, 0);
1415
1416  // If the element type isn't canonical, this won't be a canonical type either,
1417  // so fill in the canonical type field.
1418  QualType Canonical;
1419  if (!EltTy.isCanonical()) {
1420    Canonical = getConstantArrayType(getCanonicalType(EltTy), ArySize,
1421                                     ASM, EltTypeQuals);
1422    // Get the new insert position for the node we care about.
1423    ConstantArrayType *NewIP =
1424      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1425    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1426  }
1427
1428  ConstantArrayType *New = new(*this,TypeAlignment)
1429    ConstantArrayType(EltTy, Canonical, ArySize, ASM, EltTypeQuals);
1430  ConstantArrayTypes.InsertNode(New, InsertPos);
1431  Types.push_back(New);
1432  return QualType(New, 0);
1433}
1434
1435/// getIncompleteArrayType - Returns a unique reference to the type for a
1436/// incomplete array of the specified element type.
1437QualType ASTContext::getUnknownSizeVariableArrayType(QualType Ty) {
1438  QualType ElemTy = getBaseElementType(Ty);
1439  DeclarationName Name;
1440  llvm::SmallVector<QualType, 8> ATypes;
1441  QualType ATy = Ty;
1442  while (const ArrayType *AT = getAsArrayType(ATy)) {
1443    ATypes.push_back(ATy);
1444    ATy = AT->getElementType();
1445  }
1446  for (int i = ATypes.size() - 1; i >= 0; i--) {
1447    if (const VariableArrayType *VAT = getAsVariableArrayType(ATypes[i])) {
1448      ElemTy = getVariableArrayType(ElemTy, /*ArraySize*/0, ArrayType::Star,
1449                                    0, VAT->getBracketsRange());
1450    }
1451    else if (const ConstantArrayType *CAT = getAsConstantArrayType(ATypes[i])) {
1452      llvm::APSInt ConstVal(CAT->getSize());
1453      ElemTy = getConstantArrayType(ElemTy, ConstVal, ArrayType::Normal, 0);
1454    }
1455    else if (getAsIncompleteArrayType(ATypes[i])) {
1456      ElemTy = getVariableArrayType(ElemTy, /*ArraySize*/0, ArrayType::Normal,
1457                                    0, SourceRange());
1458    }
1459    else
1460      assert(false && "DependentArrayType is seen");
1461  }
1462  return ElemTy;
1463}
1464
1465/// getVariableArrayDecayedType - Returns a vla type where known sizes
1466/// are replaced with [*]
1467QualType ASTContext::getVariableArrayDecayedType(QualType Ty) {
1468  if (Ty->isPointerType()) {
1469    QualType BaseType = Ty->getAs<PointerType>()->getPointeeType();
1470    if (isa<VariableArrayType>(BaseType)) {
1471      ArrayType *AT = dyn_cast<ArrayType>(BaseType);
1472      VariableArrayType *VAT = cast<VariableArrayType>(AT);
1473      if (VAT->getSizeExpr()) {
1474        Ty = getUnknownSizeVariableArrayType(BaseType);
1475        Ty = getPointerType(Ty);
1476      }
1477    }
1478  }
1479  return Ty;
1480}
1481
1482
1483/// getVariableArrayType - Returns a non-unique reference to the type for a
1484/// variable array of the specified element type.
1485QualType ASTContext::getVariableArrayType(QualType EltTy,
1486                                          Expr *NumElts,
1487                                          ArrayType::ArraySizeModifier ASM,
1488                                          unsigned EltTypeQuals,
1489                                          SourceRange Brackets) {
1490  // Since we don't unique expressions, it isn't possible to unique VLA's
1491  // that have an expression provided for their size.
1492  QualType CanonType;
1493
1494  if (!EltTy.isCanonical()) {
1495    CanonType = getVariableArrayType(getCanonicalType(EltTy), NumElts, ASM,
1496                                     EltTypeQuals, Brackets);
1497  }
1498
1499  VariableArrayType *New = new(*this, TypeAlignment)
1500    VariableArrayType(EltTy, CanonType, NumElts, ASM, EltTypeQuals, Brackets);
1501
1502  VariableArrayTypes.push_back(New);
1503  Types.push_back(New);
1504  return QualType(New, 0);
1505}
1506
1507/// getDependentSizedArrayType - Returns a non-unique reference to
1508/// the type for a dependently-sized array of the specified element
1509/// type.
1510QualType ASTContext::getDependentSizedArrayType(QualType EltTy,
1511                                                Expr *NumElts,
1512                                                ArrayType::ArraySizeModifier ASM,
1513                                                unsigned EltTypeQuals,
1514                                                SourceRange Brackets) {
1515  assert((!NumElts || NumElts->isTypeDependent() ||
1516          NumElts->isValueDependent()) &&
1517         "Size must be type- or value-dependent!");
1518
1519  void *InsertPos = 0;
1520  DependentSizedArrayType *Canon = 0;
1521  llvm::FoldingSetNodeID ID;
1522
1523  QualType CanonicalEltTy = getCanonicalType(EltTy);
1524  if (NumElts) {
1525    // Dependently-sized array types that do not have a specified
1526    // number of elements will have their sizes deduced from an
1527    // initializer.
1528    DependentSizedArrayType::Profile(ID, *this, CanonicalEltTy, ASM,
1529                                     EltTypeQuals, NumElts);
1530
1531    Canon = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1532  }
1533
1534  DependentSizedArrayType *New;
1535  if (Canon) {
1536    // We already have a canonical version of this array type; use it as
1537    // the canonical type for a newly-built type.
1538    New = new (*this, TypeAlignment)
1539      DependentSizedArrayType(*this, EltTy, QualType(Canon, 0),
1540                              NumElts, ASM, EltTypeQuals, Brackets);
1541  } else if (CanonicalEltTy == EltTy) {
1542    // This is a canonical type. Record it.
1543    New = new (*this, TypeAlignment)
1544      DependentSizedArrayType(*this, EltTy, QualType(),
1545                              NumElts, ASM, EltTypeQuals, Brackets);
1546
1547    if (NumElts) {
1548#ifndef NDEBUG
1549      DependentSizedArrayType *CanonCheck
1550        = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1551      assert(!CanonCheck && "Dependent-sized canonical array type broken");
1552      (void)CanonCheck;
1553#endif
1554      DependentSizedArrayTypes.InsertNode(New, InsertPos);
1555    }
1556  } else {
1557    QualType Canon = getDependentSizedArrayType(CanonicalEltTy, NumElts,
1558                                                ASM, EltTypeQuals,
1559                                                SourceRange());
1560    New = new (*this, TypeAlignment)
1561      DependentSizedArrayType(*this, EltTy, Canon,
1562                              NumElts, ASM, EltTypeQuals, Brackets);
1563  }
1564
1565  Types.push_back(New);
1566  return QualType(New, 0);
1567}
1568
1569QualType ASTContext::getIncompleteArrayType(QualType EltTy,
1570                                            ArrayType::ArraySizeModifier ASM,
1571                                            unsigned EltTypeQuals) {
1572  llvm::FoldingSetNodeID ID;
1573  IncompleteArrayType::Profile(ID, EltTy, ASM, EltTypeQuals);
1574
1575  void *InsertPos = 0;
1576  if (IncompleteArrayType *ATP =
1577       IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1578    return QualType(ATP, 0);
1579
1580  // If the element type isn't canonical, this won't be a canonical type
1581  // either, so fill in the canonical type field.
1582  QualType Canonical;
1583
1584  if (!EltTy.isCanonical()) {
1585    Canonical = getIncompleteArrayType(getCanonicalType(EltTy),
1586                                       ASM, EltTypeQuals);
1587
1588    // Get the new insert position for the node we care about.
1589    IncompleteArrayType *NewIP =
1590      IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1591    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1592  }
1593
1594  IncompleteArrayType *New = new (*this, TypeAlignment)
1595    IncompleteArrayType(EltTy, Canonical, ASM, EltTypeQuals);
1596
1597  IncompleteArrayTypes.InsertNode(New, InsertPos);
1598  Types.push_back(New);
1599  return QualType(New, 0);
1600}
1601
1602/// getVectorType - Return the unique reference to a vector type of
1603/// the specified element type and size. VectorType must be a built-in type.
1604QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1605                                   VectorType::AltiVecSpecific AltiVecSpec) {
1606  BuiltinType *BaseType;
1607
1608  BaseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1609  assert(BaseType != 0 && "getVectorType(): Expecting a built-in type");
1610
1611  // Check if we've already instantiated a vector of this type.
1612  llvm::FoldingSetNodeID ID;
1613  VectorType::Profile(ID, vecType, NumElts, Type::Vector, AltiVecSpec);
1614
1615  void *InsertPos = 0;
1616  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1617    return QualType(VTP, 0);
1618
1619  // If the element type isn't canonical, this won't be a canonical type either,
1620  // so fill in the canonical type field.
1621  QualType Canonical;
1622  if (!vecType.isCanonical()) {
1623    Canonical = getVectorType(getCanonicalType(vecType), NumElts,
1624      VectorType::NotAltiVec);
1625
1626    // Get the new insert position for the node we care about.
1627    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1628    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1629  }
1630  VectorType *New = new (*this, TypeAlignment)
1631    VectorType(vecType, NumElts, Canonical, AltiVecSpec);
1632  VectorTypes.InsertNode(New, InsertPos);
1633  Types.push_back(New);
1634  return QualType(New, 0);
1635}
1636
1637/// getExtVectorType - Return the unique reference to an extended vector type of
1638/// the specified element type and size. VectorType must be a built-in type.
1639QualType ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) {
1640  BuiltinType *baseType;
1641
1642  baseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1643  assert(baseType != 0 && "getExtVectorType(): Expecting a built-in type");
1644
1645  // Check if we've already instantiated a vector of this type.
1646  llvm::FoldingSetNodeID ID;
1647  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1648                      VectorType::NotAltiVec);
1649  void *InsertPos = 0;
1650  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1651    return QualType(VTP, 0);
1652
1653  // If the element type isn't canonical, this won't be a canonical type either,
1654  // so fill in the canonical type field.
1655  QualType Canonical;
1656  if (!vecType.isCanonical()) {
1657    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
1658
1659    // Get the new insert position for the node we care about.
1660    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1661    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1662  }
1663  ExtVectorType *New = new (*this, TypeAlignment)
1664    ExtVectorType(vecType, NumElts, Canonical);
1665  VectorTypes.InsertNode(New, InsertPos);
1666  Types.push_back(New);
1667  return QualType(New, 0);
1668}
1669
1670QualType ASTContext::getDependentSizedExtVectorType(QualType vecType,
1671                                                    Expr *SizeExpr,
1672                                                    SourceLocation AttrLoc) {
1673  llvm::FoldingSetNodeID ID;
1674  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
1675                                       SizeExpr);
1676
1677  void *InsertPos = 0;
1678  DependentSizedExtVectorType *Canon
1679    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1680  DependentSizedExtVectorType *New;
1681  if (Canon) {
1682    // We already have a canonical version of this array type; use it as
1683    // the canonical type for a newly-built type.
1684    New = new (*this, TypeAlignment)
1685      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
1686                                  SizeExpr, AttrLoc);
1687  } else {
1688    QualType CanonVecTy = getCanonicalType(vecType);
1689    if (CanonVecTy == vecType) {
1690      New = new (*this, TypeAlignment)
1691        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
1692                                    AttrLoc);
1693
1694      DependentSizedExtVectorType *CanonCheck
1695        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1696      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
1697      (void)CanonCheck;
1698      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
1699    } else {
1700      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
1701                                                      SourceLocation());
1702      New = new (*this, TypeAlignment)
1703        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
1704    }
1705  }
1706
1707  Types.push_back(New);
1708  return QualType(New, 0);
1709}
1710
1711/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
1712///
1713QualType ASTContext::getFunctionNoProtoType(QualType ResultTy,
1714                                            const FunctionType::ExtInfo &Info) {
1715  const CallingConv CallConv = Info.getCC();
1716  // Unique functions, to guarantee there is only one function of a particular
1717  // structure.
1718  llvm::FoldingSetNodeID ID;
1719  FunctionNoProtoType::Profile(ID, ResultTy, Info);
1720
1721  void *InsertPos = 0;
1722  if (FunctionNoProtoType *FT =
1723        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1724    return QualType(FT, 0);
1725
1726  QualType Canonical;
1727  if (!ResultTy.isCanonical() ||
1728      getCanonicalCallConv(CallConv) != CallConv) {
1729    Canonical =
1730      getFunctionNoProtoType(getCanonicalType(ResultTy),
1731                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1732
1733    // Get the new insert position for the node we care about.
1734    FunctionNoProtoType *NewIP =
1735      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1736    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1737  }
1738
1739  FunctionNoProtoType *New = new (*this, TypeAlignment)
1740    FunctionNoProtoType(ResultTy, Canonical, Info);
1741  Types.push_back(New);
1742  FunctionNoProtoTypes.InsertNode(New, InsertPos);
1743  return QualType(New, 0);
1744}
1745
1746/// getFunctionType - Return a normal function type with a typed argument
1747/// list.  isVariadic indicates whether the argument list includes '...'.
1748QualType ASTContext::getFunctionType(QualType ResultTy,const QualType *ArgArray,
1749                                     unsigned NumArgs, bool isVariadic,
1750                                     unsigned TypeQuals, bool hasExceptionSpec,
1751                                     bool hasAnyExceptionSpec, unsigned NumExs,
1752                                     const QualType *ExArray,
1753                                     const FunctionType::ExtInfo &Info) {
1754
1755  const CallingConv CallConv= Info.getCC();
1756  // Unique functions, to guarantee there is only one function of a particular
1757  // structure.
1758  llvm::FoldingSetNodeID ID;
1759  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, isVariadic,
1760                             TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1761                             NumExs, ExArray, Info);
1762
1763  void *InsertPos = 0;
1764  if (FunctionProtoType *FTP =
1765        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1766    return QualType(FTP, 0);
1767
1768  // Determine whether the type being created is already canonical or not.
1769  bool isCanonical = !hasExceptionSpec && ResultTy.isCanonical();
1770  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
1771    if (!ArgArray[i].isCanonicalAsParam())
1772      isCanonical = false;
1773
1774  // If this type isn't canonical, get the canonical version of it.
1775  // The exception spec is not part of the canonical type.
1776  QualType Canonical;
1777  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
1778    llvm::SmallVector<QualType, 16> CanonicalArgs;
1779    CanonicalArgs.reserve(NumArgs);
1780    for (unsigned i = 0; i != NumArgs; ++i)
1781      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
1782
1783    Canonical = getFunctionType(getCanonicalType(ResultTy),
1784                                CanonicalArgs.data(), NumArgs,
1785                                isVariadic, TypeQuals, false,
1786                                false, 0, 0,
1787                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1788
1789    // Get the new insert position for the node we care about.
1790    FunctionProtoType *NewIP =
1791      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1792    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1793  }
1794
1795  // FunctionProtoType objects are allocated with extra bytes after them
1796  // for two variable size arrays (for parameter and exception types) at the
1797  // end of them.
1798  FunctionProtoType *FTP =
1799    (FunctionProtoType*)Allocate(sizeof(FunctionProtoType) +
1800                                 NumArgs*sizeof(QualType) +
1801                                 NumExs*sizeof(QualType), TypeAlignment);
1802  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, isVariadic,
1803                              TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1804                              ExArray, NumExs, Canonical, Info);
1805  Types.push_back(FTP);
1806  FunctionProtoTypes.InsertNode(FTP, InsertPos);
1807  return QualType(FTP, 0);
1808}
1809
1810#ifndef NDEBUG
1811static bool NeedsInjectedClassNameType(const RecordDecl *D) {
1812  if (!isa<CXXRecordDecl>(D)) return false;
1813  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
1814  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
1815    return true;
1816  if (RD->getDescribedClassTemplate() &&
1817      !isa<ClassTemplateSpecializationDecl>(RD))
1818    return true;
1819  return false;
1820}
1821#endif
1822
1823/// getInjectedClassNameType - Return the unique reference to the
1824/// injected class name type for the specified templated declaration.
1825QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
1826                                              QualType TST) {
1827  assert(NeedsInjectedClassNameType(Decl));
1828  if (Decl->TypeForDecl) {
1829    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1830  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDeclaration()) {
1831    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
1832    Decl->TypeForDecl = PrevDecl->TypeForDecl;
1833    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1834  } else {
1835    Decl->TypeForDecl =
1836      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
1837    Types.push_back(Decl->TypeForDecl);
1838  }
1839  return QualType(Decl->TypeForDecl, 0);
1840}
1841
1842/// getTypeDeclType - Return the unique reference to the type for the
1843/// specified type declaration.
1844QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) {
1845  assert(Decl && "Passed null for Decl param");
1846  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
1847
1848  if (const TypedefDecl *Typedef = dyn_cast<TypedefDecl>(Decl))
1849    return getTypedefType(Typedef);
1850
1851  assert(!isa<TemplateTypeParmDecl>(Decl) &&
1852         "Template type parameter types are always available.");
1853
1854  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
1855    assert(!Record->getPreviousDeclaration() &&
1856           "struct/union has previous declaration");
1857    assert(!NeedsInjectedClassNameType(Record));
1858    return getRecordType(Record);
1859  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
1860    assert(!Enum->getPreviousDeclaration() &&
1861           "enum has previous declaration");
1862    return getEnumType(Enum);
1863  } else if (const UnresolvedUsingTypenameDecl *Using =
1864               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
1865    Decl->TypeForDecl = new (*this, TypeAlignment) UnresolvedUsingType(Using);
1866  } else
1867    llvm_unreachable("TypeDecl without a type?");
1868
1869  Types.push_back(Decl->TypeForDecl);
1870  return QualType(Decl->TypeForDecl, 0);
1871}
1872
1873/// getTypedefType - Return the unique reference to the type for the
1874/// specified typename decl.
1875QualType
1876ASTContext::getTypedefType(const TypedefDecl *Decl, QualType Canonical) {
1877  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1878
1879  if (Canonical.isNull())
1880    Canonical = getCanonicalType(Decl->getUnderlyingType());
1881  Decl->TypeForDecl = new(*this, TypeAlignment)
1882    TypedefType(Type::Typedef, Decl, Canonical);
1883  Types.push_back(Decl->TypeForDecl);
1884  return QualType(Decl->TypeForDecl, 0);
1885}
1886
1887QualType ASTContext::getRecordType(const RecordDecl *Decl) {
1888  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1889
1890  if (const RecordDecl *PrevDecl = Decl->getPreviousDeclaration())
1891    if (PrevDecl->TypeForDecl)
1892      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1893
1894  Decl->TypeForDecl = new (*this, TypeAlignment) RecordType(Decl);
1895  Types.push_back(Decl->TypeForDecl);
1896  return QualType(Decl->TypeForDecl, 0);
1897}
1898
1899QualType ASTContext::getEnumType(const EnumDecl *Decl) {
1900  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1901
1902  if (const EnumDecl *PrevDecl = Decl->getPreviousDeclaration())
1903    if (PrevDecl->TypeForDecl)
1904      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1905
1906  Decl->TypeForDecl = new (*this, TypeAlignment) EnumType(Decl);
1907  Types.push_back(Decl->TypeForDecl);
1908  return QualType(Decl->TypeForDecl, 0);
1909}
1910
1911/// \brief Retrieve a substitution-result type.
1912QualType
1913ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
1914                                         QualType Replacement) {
1915  assert(Replacement.isCanonical()
1916         && "replacement types must always be canonical");
1917
1918  llvm::FoldingSetNodeID ID;
1919  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
1920  void *InsertPos = 0;
1921  SubstTemplateTypeParmType *SubstParm
1922    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1923
1924  if (!SubstParm) {
1925    SubstParm = new (*this, TypeAlignment)
1926      SubstTemplateTypeParmType(Parm, Replacement);
1927    Types.push_back(SubstParm);
1928    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
1929  }
1930
1931  return QualType(SubstParm, 0);
1932}
1933
1934/// \brief Retrieve the template type parameter type for a template
1935/// parameter or parameter pack with the given depth, index, and (optionally)
1936/// name.
1937QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
1938                                             bool ParameterPack,
1939                                             IdentifierInfo *Name) {
1940  llvm::FoldingSetNodeID ID;
1941  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, Name);
1942  void *InsertPos = 0;
1943  TemplateTypeParmType *TypeParm
1944    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1945
1946  if (TypeParm)
1947    return QualType(TypeParm, 0);
1948
1949  if (Name) {
1950    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
1951    TypeParm = new (*this, TypeAlignment)
1952      TemplateTypeParmType(Depth, Index, ParameterPack, Name, Canon);
1953
1954    TemplateTypeParmType *TypeCheck
1955      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1956    assert(!TypeCheck && "Template type parameter canonical type broken");
1957    (void)TypeCheck;
1958  } else
1959    TypeParm = new (*this, TypeAlignment)
1960      TemplateTypeParmType(Depth, Index, ParameterPack);
1961
1962  Types.push_back(TypeParm);
1963  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
1964
1965  return QualType(TypeParm, 0);
1966}
1967
1968TypeSourceInfo *
1969ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
1970                                              SourceLocation NameLoc,
1971                                        const TemplateArgumentListInfo &Args,
1972                                              QualType CanonType) {
1973  QualType TST = getTemplateSpecializationType(Name, Args, CanonType);
1974
1975  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
1976  TemplateSpecializationTypeLoc TL
1977    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
1978  TL.setTemplateNameLoc(NameLoc);
1979  TL.setLAngleLoc(Args.getLAngleLoc());
1980  TL.setRAngleLoc(Args.getRAngleLoc());
1981  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
1982    TL.setArgLocInfo(i, Args[i].getLocInfo());
1983  return DI;
1984}
1985
1986QualType
1987ASTContext::getTemplateSpecializationType(TemplateName Template,
1988                                          const TemplateArgumentListInfo &Args,
1989                                          QualType Canon) {
1990  unsigned NumArgs = Args.size();
1991
1992  llvm::SmallVector<TemplateArgument, 4> ArgVec;
1993  ArgVec.reserve(NumArgs);
1994  for (unsigned i = 0; i != NumArgs; ++i)
1995    ArgVec.push_back(Args[i].getArgument());
1996
1997  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
1998                                       Canon);
1999}
2000
2001QualType
2002ASTContext::getTemplateSpecializationType(TemplateName Template,
2003                                          const TemplateArgument *Args,
2004                                          unsigned NumArgs,
2005                                          QualType Canon) {
2006  if (!Canon.isNull())
2007    Canon = getCanonicalType(Canon);
2008  else
2009    Canon = getCanonicalTemplateSpecializationType(Template, Args, NumArgs);
2010
2011  // Allocate the (non-canonical) template specialization type, but don't
2012  // try to unique it: these types typically have location information that
2013  // we don't unique and don't want to lose.
2014  void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2015                        sizeof(TemplateArgument) * NumArgs),
2016                       TypeAlignment);
2017  TemplateSpecializationType *Spec
2018    = new (Mem) TemplateSpecializationType(Template,
2019                                           Args, NumArgs,
2020                                           Canon);
2021
2022  Types.push_back(Spec);
2023  return QualType(Spec, 0);
2024}
2025
2026QualType
2027ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
2028                                                   const TemplateArgument *Args,
2029                                                   unsigned NumArgs) {
2030  // Build the canonical template specialization type.
2031  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
2032  llvm::SmallVector<TemplateArgument, 4> CanonArgs;
2033  CanonArgs.reserve(NumArgs);
2034  for (unsigned I = 0; I != NumArgs; ++I)
2035    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
2036
2037  // Determine whether this canonical template specialization type already
2038  // exists.
2039  llvm::FoldingSetNodeID ID;
2040  TemplateSpecializationType::Profile(ID, CanonTemplate,
2041                                      CanonArgs.data(), NumArgs, *this);
2042
2043  void *InsertPos = 0;
2044  TemplateSpecializationType *Spec
2045    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2046
2047  if (!Spec) {
2048    // Allocate a new canonical template specialization type.
2049    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2050                          sizeof(TemplateArgument) * NumArgs),
2051                         TypeAlignment);
2052    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
2053                                                CanonArgs.data(), NumArgs,
2054                                                QualType());
2055    Types.push_back(Spec);
2056    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
2057  }
2058
2059  assert(Spec->isDependentType() &&
2060         "Non-dependent template-id type must have a canonical type");
2061  return QualType(Spec, 0);
2062}
2063
2064QualType
2065ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
2066                              NestedNameSpecifier *NNS,
2067                              QualType NamedType) {
2068  llvm::FoldingSetNodeID ID;
2069  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2070
2071  void *InsertPos = 0;
2072  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2073  if (T)
2074    return QualType(T, 0);
2075
2076  QualType Canon = NamedType;
2077  if (!Canon.isCanonical()) {
2078    Canon = getCanonicalType(NamedType);
2079    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2080    assert(!CheckT && "Elaborated canonical type broken");
2081    (void)CheckT;
2082  }
2083
2084  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2085  Types.push_back(T);
2086  ElaboratedTypes.InsertNode(T, InsertPos);
2087  return QualType(T, 0);
2088}
2089
2090QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2091                                          NestedNameSpecifier *NNS,
2092                                          const IdentifierInfo *Name,
2093                                          QualType Canon) {
2094  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2095
2096  if (Canon.isNull()) {
2097    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2098    ElaboratedTypeKeyword CanonKeyword = Keyword;
2099    if (Keyword == ETK_None)
2100      CanonKeyword = ETK_Typename;
2101
2102    if (CanonNNS != NNS || CanonKeyword != Keyword)
2103      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2104  }
2105
2106  llvm::FoldingSetNodeID ID;
2107  DependentNameType::Profile(ID, Keyword, NNS, Name);
2108
2109  void *InsertPos = 0;
2110  DependentNameType *T
2111    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2112  if (T)
2113    return QualType(T, 0);
2114
2115  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2116  Types.push_back(T);
2117  DependentNameTypes.InsertNode(T, InsertPos);
2118  return QualType(T, 0);
2119}
2120
2121QualType
2122ASTContext::getDependentTemplateSpecializationType(
2123                                 ElaboratedTypeKeyword Keyword,
2124                                 NestedNameSpecifier *NNS,
2125                                 const IdentifierInfo *Name,
2126                                 const TemplateArgumentListInfo &Args) {
2127  // TODO: avoid this copy
2128  llvm::SmallVector<TemplateArgument, 16> ArgCopy;
2129  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2130    ArgCopy.push_back(Args[I].getArgument());
2131  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2132                                                ArgCopy.size(),
2133                                                ArgCopy.data());
2134}
2135
2136QualType
2137ASTContext::getDependentTemplateSpecializationType(
2138                                 ElaboratedTypeKeyword Keyword,
2139                                 NestedNameSpecifier *NNS,
2140                                 const IdentifierInfo *Name,
2141                                 unsigned NumArgs,
2142                                 const TemplateArgument *Args) {
2143  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2144
2145  llvm::FoldingSetNodeID ID;
2146  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2147                                               Name, NumArgs, Args);
2148
2149  void *InsertPos = 0;
2150  DependentTemplateSpecializationType *T
2151    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2152  if (T)
2153    return QualType(T, 0);
2154
2155  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2156
2157  ElaboratedTypeKeyword CanonKeyword = Keyword;
2158  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2159
2160  bool AnyNonCanonArgs = false;
2161  llvm::SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2162  for (unsigned I = 0; I != NumArgs; ++I) {
2163    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2164    if (!CanonArgs[I].structurallyEquals(Args[I]))
2165      AnyNonCanonArgs = true;
2166  }
2167
2168  QualType Canon;
2169  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2170    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2171                                                   Name, NumArgs,
2172                                                   CanonArgs.data());
2173
2174    // Find the insert position again.
2175    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2176  }
2177
2178  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2179                        sizeof(TemplateArgument) * NumArgs),
2180                       TypeAlignment);
2181  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2182                                                    Name, NumArgs, Args, Canon);
2183  Types.push_back(T);
2184  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2185  return QualType(T, 0);
2186}
2187
2188/// CmpProtocolNames - Comparison predicate for sorting protocols
2189/// alphabetically.
2190static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2191                            const ObjCProtocolDecl *RHS) {
2192  return LHS->getDeclName() < RHS->getDeclName();
2193}
2194
2195static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2196                                unsigned NumProtocols) {
2197  if (NumProtocols == 0) return true;
2198
2199  for (unsigned i = 1; i != NumProtocols; ++i)
2200    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]))
2201      return false;
2202  return true;
2203}
2204
2205static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2206                                   unsigned &NumProtocols) {
2207  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2208
2209  // Sort protocols, keyed by name.
2210  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2211
2212  // Remove duplicates.
2213  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2214  NumProtocols = ProtocolsEnd-Protocols;
2215}
2216
2217QualType ASTContext::getObjCObjectType(QualType BaseType,
2218                                       ObjCProtocolDecl * const *Protocols,
2219                                       unsigned NumProtocols) {
2220  // If the base type is an interface and there aren't any protocols
2221  // to add, then the interface type will do just fine.
2222  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2223    return BaseType;
2224
2225  // Look in the folding set for an existing type.
2226  llvm::FoldingSetNodeID ID;
2227  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2228  void *InsertPos = 0;
2229  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2230    return QualType(QT, 0);
2231
2232  // Build the canonical type, which has the canonical base type and
2233  // a sorted-and-uniqued list of protocols.
2234  QualType Canonical;
2235  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2236  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2237    if (!ProtocolsSorted) {
2238      llvm::SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2239                                                     Protocols + NumProtocols);
2240      unsigned UniqueCount = NumProtocols;
2241
2242      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2243      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2244                                    &Sorted[0], UniqueCount);
2245    } else {
2246      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2247                                    Protocols, NumProtocols);
2248    }
2249
2250    // Regenerate InsertPos.
2251    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2252  }
2253
2254  unsigned Size = sizeof(ObjCObjectTypeImpl);
2255  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2256  void *Mem = Allocate(Size, TypeAlignment);
2257  ObjCObjectTypeImpl *T =
2258    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2259
2260  Types.push_back(T);
2261  ObjCObjectTypes.InsertNode(T, InsertPos);
2262  return QualType(T, 0);
2263}
2264
2265/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2266/// the given object type.
2267QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) {
2268  llvm::FoldingSetNodeID ID;
2269  ObjCObjectPointerType::Profile(ID, ObjectT);
2270
2271  void *InsertPos = 0;
2272  if (ObjCObjectPointerType *QT =
2273              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2274    return QualType(QT, 0);
2275
2276  // Find the canonical object type.
2277  QualType Canonical;
2278  if (!ObjectT.isCanonical()) {
2279    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2280
2281    // Regenerate InsertPos.
2282    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2283  }
2284
2285  // No match.
2286  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2287  ObjCObjectPointerType *QType =
2288    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2289
2290  Types.push_back(QType);
2291  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2292  return QualType(QType, 0);
2293}
2294
2295/// getObjCInterfaceType - Return the unique reference to the type for the
2296/// specified ObjC interface decl. The list of protocols is optional.
2297QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl) {
2298  if (Decl->TypeForDecl)
2299    return QualType(Decl->TypeForDecl, 0);
2300
2301  // FIXME: redeclarations?
2302  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2303  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2304  Decl->TypeForDecl = T;
2305  Types.push_back(T);
2306  return QualType(T, 0);
2307}
2308
2309/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2310/// TypeOfExprType AST's (since expression's are never shared). For example,
2311/// multiple declarations that refer to "typeof(x)" all contain different
2312/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2313/// on canonical type's (which are always unique).
2314QualType ASTContext::getTypeOfExprType(Expr *tofExpr) {
2315  TypeOfExprType *toe;
2316  if (tofExpr->isTypeDependent()) {
2317    llvm::FoldingSetNodeID ID;
2318    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2319
2320    void *InsertPos = 0;
2321    DependentTypeOfExprType *Canon
2322      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2323    if (Canon) {
2324      // We already have a "canonical" version of an identical, dependent
2325      // typeof(expr) type. Use that as our canonical type.
2326      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2327                                          QualType((TypeOfExprType*)Canon, 0));
2328    }
2329    else {
2330      // Build a new, canonical typeof(expr) type.
2331      Canon
2332        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2333      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2334      toe = Canon;
2335    }
2336  } else {
2337    QualType Canonical = getCanonicalType(tofExpr->getType());
2338    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2339  }
2340  Types.push_back(toe);
2341  return QualType(toe, 0);
2342}
2343
2344/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2345/// TypeOfType AST's. The only motivation to unique these nodes would be
2346/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2347/// an issue. This doesn't effect the type checker, since it operates
2348/// on canonical type's (which are always unique).
2349QualType ASTContext::getTypeOfType(QualType tofType) {
2350  QualType Canonical = getCanonicalType(tofType);
2351  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2352  Types.push_back(tot);
2353  return QualType(tot, 0);
2354}
2355
2356/// getDecltypeForExpr - Given an expr, will return the decltype for that
2357/// expression, according to the rules in C++0x [dcl.type.simple]p4
2358static QualType getDecltypeForExpr(const Expr *e, ASTContext &Context) {
2359  if (e->isTypeDependent())
2360    return Context.DependentTy;
2361
2362  // If e is an id expression or a class member access, decltype(e) is defined
2363  // as the type of the entity named by e.
2364  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2365    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2366      return VD->getType();
2367  }
2368  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2369    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2370      return FD->getType();
2371  }
2372  // If e is a function call or an invocation of an overloaded operator,
2373  // (parentheses around e are ignored), decltype(e) is defined as the
2374  // return type of that function.
2375  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2376    return CE->getCallReturnType();
2377
2378  QualType T = e->getType();
2379
2380  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2381  // defined as T&, otherwise decltype(e) is defined as T.
2382  if (e->isLvalue(Context) == Expr::LV_Valid)
2383    T = Context.getLValueReferenceType(T);
2384
2385  return T;
2386}
2387
2388/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2389/// DecltypeType AST's. The only motivation to unique these nodes would be
2390/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2391/// an issue. This doesn't effect the type checker, since it operates
2392/// on canonical type's (which are always unique).
2393QualType ASTContext::getDecltypeType(Expr *e) {
2394  DecltypeType *dt;
2395  if (e->isTypeDependent()) {
2396    llvm::FoldingSetNodeID ID;
2397    DependentDecltypeType::Profile(ID, *this, e);
2398
2399    void *InsertPos = 0;
2400    DependentDecltypeType *Canon
2401      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2402    if (Canon) {
2403      // We already have a "canonical" version of an equivalent, dependent
2404      // decltype type. Use that as our canonical type.
2405      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2406                                       QualType((DecltypeType*)Canon, 0));
2407    }
2408    else {
2409      // Build a new, canonical typeof(expr) type.
2410      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2411      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2412      dt = Canon;
2413    }
2414  } else {
2415    QualType T = getDecltypeForExpr(e, *this);
2416    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2417  }
2418  Types.push_back(dt);
2419  return QualType(dt, 0);
2420}
2421
2422/// getTagDeclType - Return the unique reference to the type for the
2423/// specified TagDecl (struct/union/class/enum) decl.
2424QualType ASTContext::getTagDeclType(const TagDecl *Decl) {
2425  assert (Decl);
2426  // FIXME: What is the design on getTagDeclType when it requires casting
2427  // away const?  mutable?
2428  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2429}
2430
2431/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2432/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2433/// needs to agree with the definition in <stddef.h>.
2434CanQualType ASTContext::getSizeType() const {
2435  return getFromTargetType(Target.getSizeType());
2436}
2437
2438/// getSignedWCharType - Return the type of "signed wchar_t".
2439/// Used when in C++, as a GCC extension.
2440QualType ASTContext::getSignedWCharType() const {
2441  // FIXME: derive from "Target" ?
2442  return WCharTy;
2443}
2444
2445/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
2446/// Used when in C++, as a GCC extension.
2447QualType ASTContext::getUnsignedWCharType() const {
2448  // FIXME: derive from "Target" ?
2449  return UnsignedIntTy;
2450}
2451
2452/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
2453/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
2454QualType ASTContext::getPointerDiffType() const {
2455  return getFromTargetType(Target.getPtrDiffType(0));
2456}
2457
2458//===----------------------------------------------------------------------===//
2459//                              Type Operators
2460//===----------------------------------------------------------------------===//
2461
2462CanQualType ASTContext::getCanonicalParamType(QualType T) {
2463  // Push qualifiers into arrays, and then discard any remaining
2464  // qualifiers.
2465  T = getCanonicalType(T);
2466  T = getVariableArrayDecayedType(T);
2467  const Type *Ty = T.getTypePtr();
2468  QualType Result;
2469  if (isa<ArrayType>(Ty)) {
2470    Result = getArrayDecayedType(QualType(Ty,0));
2471  } else if (isa<FunctionType>(Ty)) {
2472    Result = getPointerType(QualType(Ty, 0));
2473  } else {
2474    Result = QualType(Ty, 0);
2475  }
2476
2477  return CanQualType::CreateUnsafe(Result);
2478}
2479
2480/// getCanonicalType - Return the canonical (structural) type corresponding to
2481/// the specified potentially non-canonical type.  The non-canonical version
2482/// of a type may have many "decorated" versions of types.  Decorators can
2483/// include typedefs, 'typeof' operators, etc. The returned type is guaranteed
2484/// to be free of any of these, allowing two canonical types to be compared
2485/// for exact equality with a simple pointer comparison.
2486CanQualType ASTContext::getCanonicalType(QualType T) {
2487  QualifierCollector Quals;
2488  const Type *Ptr = Quals.strip(T);
2489  QualType CanType = Ptr->getCanonicalTypeInternal();
2490
2491  // The canonical internal type will be the canonical type *except*
2492  // that we push type qualifiers down through array types.
2493
2494  // If there are no new qualifiers to push down, stop here.
2495  if (!Quals.hasQualifiers())
2496    return CanQualType::CreateUnsafe(CanType);
2497
2498  // If the type qualifiers are on an array type, get the canonical
2499  // type of the array with the qualifiers applied to the element
2500  // type.
2501  ArrayType *AT = dyn_cast<ArrayType>(CanType);
2502  if (!AT)
2503    return CanQualType::CreateUnsafe(getQualifiedType(CanType, Quals));
2504
2505  // Get the canonical version of the element with the extra qualifiers on it.
2506  // This can recursively sink qualifiers through multiple levels of arrays.
2507  QualType NewEltTy = getQualifiedType(AT->getElementType(), Quals);
2508  NewEltTy = getCanonicalType(NewEltTy);
2509
2510  if (ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
2511    return CanQualType::CreateUnsafe(
2512             getConstantArrayType(NewEltTy, CAT->getSize(),
2513                                  CAT->getSizeModifier(),
2514                                  CAT->getIndexTypeCVRQualifiers()));
2515  if (IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT))
2516    return CanQualType::CreateUnsafe(
2517             getIncompleteArrayType(NewEltTy, IAT->getSizeModifier(),
2518                                    IAT->getIndexTypeCVRQualifiers()));
2519
2520  if (DependentSizedArrayType *DSAT = dyn_cast<DependentSizedArrayType>(AT))
2521    return CanQualType::CreateUnsafe(
2522             getDependentSizedArrayType(NewEltTy,
2523                                        DSAT->getSizeExpr(),
2524                                        DSAT->getSizeModifier(),
2525                                        DSAT->getIndexTypeCVRQualifiers(),
2526                        DSAT->getBracketsRange())->getCanonicalTypeInternal());
2527
2528  VariableArrayType *VAT = cast<VariableArrayType>(AT);
2529  return CanQualType::CreateUnsafe(getVariableArrayType(NewEltTy,
2530                                                        VAT->getSizeExpr(),
2531                                                        VAT->getSizeModifier(),
2532                                              VAT->getIndexTypeCVRQualifiers(),
2533                                                     VAT->getBracketsRange()));
2534}
2535
2536QualType ASTContext::getUnqualifiedArrayType(QualType T,
2537                                             Qualifiers &Quals) {
2538  Quals = T.getQualifiers();
2539  const ArrayType *AT = getAsArrayType(T);
2540  if (!AT) {
2541    return T.getUnqualifiedType();
2542  }
2543
2544  QualType Elt = AT->getElementType();
2545  QualType UnqualElt = getUnqualifiedArrayType(Elt, Quals);
2546  if (Elt == UnqualElt)
2547    return T;
2548
2549  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
2550    return getConstantArrayType(UnqualElt, CAT->getSize(),
2551                                CAT->getSizeModifier(), 0);
2552  }
2553
2554  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
2555    return getIncompleteArrayType(UnqualElt, IAT->getSizeModifier(), 0);
2556  }
2557
2558  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
2559    return getVariableArrayType(UnqualElt,
2560                                VAT->getSizeExpr(),
2561                                VAT->getSizeModifier(),
2562                                VAT->getIndexTypeCVRQualifiers(),
2563                                VAT->getBracketsRange());
2564  }
2565
2566  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
2567  return getDependentSizedArrayType(UnqualElt, DSAT->getSizeExpr(),
2568                                    DSAT->getSizeModifier(), 0,
2569                                    SourceRange());
2570}
2571
2572/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
2573/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
2574/// they point to and return true. If T1 and T2 aren't pointer types
2575/// or pointer-to-member types, or if they are not similar at this
2576/// level, returns false and leaves T1 and T2 unchanged. Top-level
2577/// qualifiers on T1 and T2 are ignored. This function will typically
2578/// be called in a loop that successively "unwraps" pointer and
2579/// pointer-to-member types to compare them at each level.
2580bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
2581  const PointerType *T1PtrType = T1->getAs<PointerType>(),
2582                    *T2PtrType = T2->getAs<PointerType>();
2583  if (T1PtrType && T2PtrType) {
2584    T1 = T1PtrType->getPointeeType();
2585    T2 = T2PtrType->getPointeeType();
2586    return true;
2587  }
2588
2589  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
2590                          *T2MPType = T2->getAs<MemberPointerType>();
2591  if (T1MPType && T2MPType &&
2592      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
2593                             QualType(T2MPType->getClass(), 0))) {
2594    T1 = T1MPType->getPointeeType();
2595    T2 = T2MPType->getPointeeType();
2596    return true;
2597  }
2598
2599  if (getLangOptions().ObjC1) {
2600    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
2601                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
2602    if (T1OPType && T2OPType) {
2603      T1 = T1OPType->getPointeeType();
2604      T2 = T2OPType->getPointeeType();
2605      return true;
2606    }
2607  }
2608
2609  // FIXME: Block pointers, too?
2610
2611  return false;
2612}
2613
2614DeclarationNameInfo ASTContext::getNameForTemplate(TemplateName Name,
2615                                                   SourceLocation NameLoc) {
2616  if (TemplateDecl *TD = Name.getAsTemplateDecl())
2617    // DNInfo work in progress: CHECKME: what about DNLoc?
2618    return DeclarationNameInfo(TD->getDeclName(), NameLoc);
2619
2620  if (DependentTemplateName *DTN = Name.getAsDependentTemplateName()) {
2621    DeclarationName DName;
2622    if (DTN->isIdentifier()) {
2623      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
2624      return DeclarationNameInfo(DName, NameLoc);
2625    } else {
2626      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
2627      // DNInfo work in progress: FIXME: source locations?
2628      DeclarationNameLoc DNLoc;
2629      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
2630      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
2631      return DeclarationNameInfo(DName, NameLoc, DNLoc);
2632    }
2633  }
2634
2635  OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
2636  assert(Storage);
2637  // DNInfo work in progress: CHECKME: what about DNLoc?
2638  return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
2639}
2640
2641TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) {
2642  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
2643    if (TemplateTemplateParmDecl *TTP
2644                              = dyn_cast<TemplateTemplateParmDecl>(Template))
2645      Template = getCanonicalTemplateTemplateParmDecl(TTP);
2646
2647    // The canonical template name is the canonical template declaration.
2648    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
2649  }
2650
2651  assert(!Name.getAsOverloadedTemplate());
2652
2653  DependentTemplateName *DTN = Name.getAsDependentTemplateName();
2654  assert(DTN && "Non-dependent template names must refer to template decls.");
2655  return DTN->CanonicalTemplateName;
2656}
2657
2658bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
2659  X = getCanonicalTemplateName(X);
2660  Y = getCanonicalTemplateName(Y);
2661  return X.getAsVoidPointer() == Y.getAsVoidPointer();
2662}
2663
2664TemplateArgument
2665ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) {
2666  switch (Arg.getKind()) {
2667    case TemplateArgument::Null:
2668      return Arg;
2669
2670    case TemplateArgument::Expression:
2671      return Arg;
2672
2673    case TemplateArgument::Declaration:
2674      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
2675
2676    case TemplateArgument::Template:
2677      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
2678
2679    case TemplateArgument::Integral:
2680      return TemplateArgument(*Arg.getAsIntegral(),
2681                              getCanonicalType(Arg.getIntegralType()));
2682
2683    case TemplateArgument::Type:
2684      return TemplateArgument(getCanonicalType(Arg.getAsType()));
2685
2686    case TemplateArgument::Pack: {
2687      TemplateArgument *CanonArgs
2688        = new (*this) TemplateArgument[Arg.pack_size()];
2689      unsigned Idx = 0;
2690      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
2691                                        AEnd = Arg.pack_end();
2692           A != AEnd; (void)++A, ++Idx)
2693        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
2694
2695      return TemplateArgument(CanonArgs, Arg.pack_size());
2696    }
2697  }
2698
2699  // Silence GCC warning
2700  assert(false && "Unhandled template argument kind");
2701  return TemplateArgument();
2702}
2703
2704NestedNameSpecifier *
2705ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) {
2706  if (!NNS)
2707    return 0;
2708
2709  switch (NNS->getKind()) {
2710  case NestedNameSpecifier::Identifier:
2711    // Canonicalize the prefix but keep the identifier the same.
2712    return NestedNameSpecifier::Create(*this,
2713                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
2714                                       NNS->getAsIdentifier());
2715
2716  case NestedNameSpecifier::Namespace:
2717    // A namespace is canonical; build a nested-name-specifier with
2718    // this namespace and no prefix.
2719    return NestedNameSpecifier::Create(*this, 0, NNS->getAsNamespace());
2720
2721  case NestedNameSpecifier::TypeSpec:
2722  case NestedNameSpecifier::TypeSpecWithTemplate: {
2723    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
2724
2725    // If we have some kind of dependent-named type (e.g., "typename T::type"),
2726    // break it apart into its prefix and identifier, then reconsititute those
2727    // as the canonical nested-name-specifier. This is required to canonicalize
2728    // a dependent nested-name-specifier involving typedefs of dependent-name
2729    // types, e.g.,
2730    //   typedef typename T::type T1;
2731    //   typedef typename T1::type T2;
2732    if (const DependentNameType *DNT = T->getAs<DependentNameType>()) {
2733      NestedNameSpecifier *Prefix
2734        = getCanonicalNestedNameSpecifier(DNT->getQualifier());
2735      return NestedNameSpecifier::Create(*this, Prefix,
2736                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
2737    }
2738
2739    // Do the same thing as above, but with dependent-named specializations.
2740    if (const DependentTemplateSpecializationType *DTST
2741          = T->getAs<DependentTemplateSpecializationType>()) {
2742      NestedNameSpecifier *Prefix
2743        = getCanonicalNestedNameSpecifier(DTST->getQualifier());
2744      TemplateName Name
2745        = getDependentTemplateName(Prefix, DTST->getIdentifier());
2746      T = getTemplateSpecializationType(Name,
2747                                        DTST->getArgs(), DTST->getNumArgs());
2748      T = getCanonicalType(T);
2749    }
2750
2751    return NestedNameSpecifier::Create(*this, 0, false, T.getTypePtr());
2752  }
2753
2754  case NestedNameSpecifier::Global:
2755    // The global specifier is canonical and unique.
2756    return NNS;
2757  }
2758
2759  // Required to silence a GCC warning
2760  return 0;
2761}
2762
2763
2764const ArrayType *ASTContext::getAsArrayType(QualType T) {
2765  // Handle the non-qualified case efficiently.
2766  if (!T.hasLocalQualifiers()) {
2767    // Handle the common positive case fast.
2768    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
2769      return AT;
2770  }
2771
2772  // Handle the common negative case fast.
2773  QualType CType = T->getCanonicalTypeInternal();
2774  if (!isa<ArrayType>(CType))
2775    return 0;
2776
2777  // Apply any qualifiers from the array type to the element type.  This
2778  // implements C99 6.7.3p8: "If the specification of an array type includes
2779  // any type qualifiers, the element type is so qualified, not the array type."
2780
2781  // If we get here, we either have type qualifiers on the type, or we have
2782  // sugar such as a typedef in the way.  If we have type qualifiers on the type
2783  // we must propagate them down into the element type.
2784
2785  QualifierCollector Qs;
2786  const Type *Ty = Qs.strip(T.getDesugaredType());
2787
2788  // If we have a simple case, just return now.
2789  const ArrayType *ATy = dyn_cast<ArrayType>(Ty);
2790  if (ATy == 0 || Qs.empty())
2791    return ATy;
2792
2793  // Otherwise, we have an array and we have qualifiers on it.  Push the
2794  // qualifiers into the array element type and return a new array type.
2795  // Get the canonical version of the element with the extra qualifiers on it.
2796  // This can recursively sink qualifiers through multiple levels of arrays.
2797  QualType NewEltTy = getQualifiedType(ATy->getElementType(), Qs);
2798
2799  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
2800    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
2801                                                CAT->getSizeModifier(),
2802                                           CAT->getIndexTypeCVRQualifiers()));
2803  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
2804    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
2805                                                  IAT->getSizeModifier(),
2806                                           IAT->getIndexTypeCVRQualifiers()));
2807
2808  if (const DependentSizedArrayType *DSAT
2809        = dyn_cast<DependentSizedArrayType>(ATy))
2810    return cast<ArrayType>(
2811                     getDependentSizedArrayType(NewEltTy,
2812                                                DSAT->getSizeExpr(),
2813                                                DSAT->getSizeModifier(),
2814                                              DSAT->getIndexTypeCVRQualifiers(),
2815                                                DSAT->getBracketsRange()));
2816
2817  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
2818  return cast<ArrayType>(getVariableArrayType(NewEltTy,
2819                                              VAT->getSizeExpr(),
2820                                              VAT->getSizeModifier(),
2821                                              VAT->getIndexTypeCVRQualifiers(),
2822                                              VAT->getBracketsRange()));
2823}
2824
2825/// getArrayDecayedType - Return the properly qualified result of decaying the
2826/// specified array type to a pointer.  This operation is non-trivial when
2827/// handling typedefs etc.  The canonical type of "T" must be an array type,
2828/// this returns a pointer to a properly qualified element of the array.
2829///
2830/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
2831QualType ASTContext::getArrayDecayedType(QualType Ty) {
2832  // Get the element type with 'getAsArrayType' so that we don't lose any
2833  // typedefs in the element type of the array.  This also handles propagation
2834  // of type qualifiers from the array type into the element type if present
2835  // (C99 6.7.3p8).
2836  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
2837  assert(PrettyArrayType && "Not an array type!");
2838
2839  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
2840
2841  // int x[restrict 4] ->  int *restrict
2842  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
2843}
2844
2845QualType ASTContext::getBaseElementType(QualType QT) {
2846  QualifierCollector Qs;
2847  while (const ArrayType *AT = getAsArrayType(QualType(Qs.strip(QT), 0)))
2848    QT = AT->getElementType();
2849  return Qs.apply(QT);
2850}
2851
2852QualType ASTContext::getBaseElementType(const ArrayType *AT) {
2853  QualType ElemTy = AT->getElementType();
2854
2855  if (const ArrayType *AT = getAsArrayType(ElemTy))
2856    return getBaseElementType(AT);
2857
2858  return ElemTy;
2859}
2860
2861/// getConstantArrayElementCount - Returns number of constant array elements.
2862uint64_t
2863ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
2864  uint64_t ElementCount = 1;
2865  do {
2866    ElementCount *= CA->getSize().getZExtValue();
2867    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
2868  } while (CA);
2869  return ElementCount;
2870}
2871
2872/// getFloatingRank - Return a relative rank for floating point types.
2873/// This routine will assert if passed a built-in type that isn't a float.
2874static FloatingRank getFloatingRank(QualType T) {
2875  if (const ComplexType *CT = T->getAs<ComplexType>())
2876    return getFloatingRank(CT->getElementType());
2877
2878  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
2879  switch (T->getAs<BuiltinType>()->getKind()) {
2880  default: assert(0 && "getFloatingRank(): not a floating type");
2881  case BuiltinType::Float:      return FloatRank;
2882  case BuiltinType::Double:     return DoubleRank;
2883  case BuiltinType::LongDouble: return LongDoubleRank;
2884  }
2885}
2886
2887/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
2888/// point or a complex type (based on typeDomain/typeSize).
2889/// 'typeDomain' is a real floating point or complex type.
2890/// 'typeSize' is a real floating point or complex type.
2891QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
2892                                                       QualType Domain) const {
2893  FloatingRank EltRank = getFloatingRank(Size);
2894  if (Domain->isComplexType()) {
2895    switch (EltRank) {
2896    default: assert(0 && "getFloatingRank(): illegal value for rank");
2897    case FloatRank:      return FloatComplexTy;
2898    case DoubleRank:     return DoubleComplexTy;
2899    case LongDoubleRank: return LongDoubleComplexTy;
2900    }
2901  }
2902
2903  assert(Domain->isRealFloatingType() && "Unknown domain!");
2904  switch (EltRank) {
2905  default: assert(0 && "getFloatingRank(): illegal value for rank");
2906  case FloatRank:      return FloatTy;
2907  case DoubleRank:     return DoubleTy;
2908  case LongDoubleRank: return LongDoubleTy;
2909  }
2910}
2911
2912/// getFloatingTypeOrder - Compare the rank of the two specified floating
2913/// point types, ignoring the domain of the type (i.e. 'double' ==
2914/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2915/// LHS < RHS, return -1.
2916int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) {
2917  FloatingRank LHSR = getFloatingRank(LHS);
2918  FloatingRank RHSR = getFloatingRank(RHS);
2919
2920  if (LHSR == RHSR)
2921    return 0;
2922  if (LHSR > RHSR)
2923    return 1;
2924  return -1;
2925}
2926
2927/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
2928/// routine will assert if passed a built-in type that isn't an integer or enum,
2929/// or if it is not canonicalized.
2930unsigned ASTContext::getIntegerRank(Type *T) {
2931  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
2932  if (EnumType* ET = dyn_cast<EnumType>(T))
2933    T = ET->getDecl()->getPromotionType().getTypePtr();
2934
2935  if (T->isSpecificBuiltinType(BuiltinType::WChar))
2936    T = getFromTargetType(Target.getWCharType()).getTypePtr();
2937
2938  if (T->isSpecificBuiltinType(BuiltinType::Char16))
2939    T = getFromTargetType(Target.getChar16Type()).getTypePtr();
2940
2941  if (T->isSpecificBuiltinType(BuiltinType::Char32))
2942    T = getFromTargetType(Target.getChar32Type()).getTypePtr();
2943
2944  switch (cast<BuiltinType>(T)->getKind()) {
2945  default: assert(0 && "getIntegerRank(): not a built-in integer");
2946  case BuiltinType::Bool:
2947    return 1 + (getIntWidth(BoolTy) << 3);
2948  case BuiltinType::Char_S:
2949  case BuiltinType::Char_U:
2950  case BuiltinType::SChar:
2951  case BuiltinType::UChar:
2952    return 2 + (getIntWidth(CharTy) << 3);
2953  case BuiltinType::Short:
2954  case BuiltinType::UShort:
2955    return 3 + (getIntWidth(ShortTy) << 3);
2956  case BuiltinType::Int:
2957  case BuiltinType::UInt:
2958    return 4 + (getIntWidth(IntTy) << 3);
2959  case BuiltinType::Long:
2960  case BuiltinType::ULong:
2961    return 5 + (getIntWidth(LongTy) << 3);
2962  case BuiltinType::LongLong:
2963  case BuiltinType::ULongLong:
2964    return 6 + (getIntWidth(LongLongTy) << 3);
2965  case BuiltinType::Int128:
2966  case BuiltinType::UInt128:
2967    return 7 + (getIntWidth(Int128Ty) << 3);
2968  }
2969}
2970
2971/// \brief Whether this is a promotable bitfield reference according
2972/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
2973///
2974/// \returns the type this bit-field will promote to, or NULL if no
2975/// promotion occurs.
2976QualType ASTContext::isPromotableBitField(Expr *E) {
2977  if (E->isTypeDependent() || E->isValueDependent())
2978    return QualType();
2979
2980  FieldDecl *Field = E->getBitField();
2981  if (!Field)
2982    return QualType();
2983
2984  QualType FT = Field->getType();
2985
2986  llvm::APSInt BitWidthAP = Field->getBitWidth()->EvaluateAsInt(*this);
2987  uint64_t BitWidth = BitWidthAP.getZExtValue();
2988  uint64_t IntSize = getTypeSize(IntTy);
2989  // GCC extension compatibility: if the bit-field size is less than or equal
2990  // to the size of int, it gets promoted no matter what its type is.
2991  // For instance, unsigned long bf : 4 gets promoted to signed int.
2992  if (BitWidth < IntSize)
2993    return IntTy;
2994
2995  if (BitWidth == IntSize)
2996    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
2997
2998  // Types bigger than int are not subject to promotions, and therefore act
2999  // like the base type.
3000  // FIXME: This doesn't quite match what gcc does, but what gcc does here
3001  // is ridiculous.
3002  return QualType();
3003}
3004
3005/// getPromotedIntegerType - Returns the type that Promotable will
3006/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
3007/// integer type.
3008QualType ASTContext::getPromotedIntegerType(QualType Promotable) {
3009  assert(!Promotable.isNull());
3010  assert(Promotable->isPromotableIntegerType());
3011  if (const EnumType *ET = Promotable->getAs<EnumType>())
3012    return ET->getDecl()->getPromotionType();
3013  if (Promotable->isSignedIntegerType())
3014    return IntTy;
3015  uint64_t PromotableSize = getTypeSize(Promotable);
3016  uint64_t IntSize = getTypeSize(IntTy);
3017  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3018  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3019}
3020
3021/// getIntegerTypeOrder - Returns the highest ranked integer type:
3022/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3023/// LHS < RHS, return -1.
3024int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) {
3025  Type *LHSC = getCanonicalType(LHS).getTypePtr();
3026  Type *RHSC = getCanonicalType(RHS).getTypePtr();
3027  if (LHSC == RHSC) return 0;
3028
3029  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3030  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3031
3032  unsigned LHSRank = getIntegerRank(LHSC);
3033  unsigned RHSRank = getIntegerRank(RHSC);
3034
3035  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3036    if (LHSRank == RHSRank) return 0;
3037    return LHSRank > RHSRank ? 1 : -1;
3038  }
3039
3040  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3041  if (LHSUnsigned) {
3042    // If the unsigned [LHS] type is larger, return it.
3043    if (LHSRank >= RHSRank)
3044      return 1;
3045
3046    // If the signed type can represent all values of the unsigned type, it
3047    // wins.  Because we are dealing with 2's complement and types that are
3048    // powers of two larger than each other, this is always safe.
3049    return -1;
3050  }
3051
3052  // If the unsigned [RHS] type is larger, return it.
3053  if (RHSRank >= LHSRank)
3054    return -1;
3055
3056  // If the signed type can represent all values of the unsigned type, it
3057  // wins.  Because we are dealing with 2's complement and types that are
3058  // powers of two larger than each other, this is always safe.
3059  return 1;
3060}
3061
3062static RecordDecl *
3063CreateRecordDecl(ASTContext &Ctx, RecordDecl::TagKind TK, DeclContext *DC,
3064                 SourceLocation L, IdentifierInfo *Id) {
3065  if (Ctx.getLangOptions().CPlusPlus)
3066    return CXXRecordDecl::Create(Ctx, TK, DC, L, Id);
3067  else
3068    return RecordDecl::Create(Ctx, TK, DC, L, Id);
3069}
3070
3071// getCFConstantStringType - Return the type used for constant CFStrings.
3072QualType ASTContext::getCFConstantStringType() {
3073  if (!CFConstantStringTypeDecl) {
3074    CFConstantStringTypeDecl =
3075      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3076                       &Idents.get("NSConstantString"));
3077    CFConstantStringTypeDecl->startDefinition();
3078
3079    QualType FieldTypes[4];
3080
3081    // const int *isa;
3082    FieldTypes[0] = getPointerType(IntTy.withConst());
3083    // int flags;
3084    FieldTypes[1] = IntTy;
3085    // const char *str;
3086    FieldTypes[2] = getPointerType(CharTy.withConst());
3087    // long length;
3088    FieldTypes[3] = LongTy;
3089
3090    // Create fields
3091    for (unsigned i = 0; i < 4; ++i) {
3092      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3093                                           SourceLocation(), 0,
3094                                           FieldTypes[i], /*TInfo=*/0,
3095                                           /*BitWidth=*/0,
3096                                           /*Mutable=*/false);
3097      Field->setAccess(AS_public);
3098      CFConstantStringTypeDecl->addDecl(Field);
3099    }
3100
3101    CFConstantStringTypeDecl->completeDefinition();
3102  }
3103
3104  return getTagDeclType(CFConstantStringTypeDecl);
3105}
3106
3107void ASTContext::setCFConstantStringType(QualType T) {
3108  const RecordType *Rec = T->getAs<RecordType>();
3109  assert(Rec && "Invalid CFConstantStringType");
3110  CFConstantStringTypeDecl = Rec->getDecl();
3111}
3112
3113// getNSConstantStringType - Return the type used for constant NSStrings.
3114QualType ASTContext::getNSConstantStringType() {
3115  if (!NSConstantStringTypeDecl) {
3116    NSConstantStringTypeDecl =
3117    CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3118                     &Idents.get("__builtin_NSString"));
3119    NSConstantStringTypeDecl->startDefinition();
3120
3121    QualType FieldTypes[3];
3122
3123    // const int *isa;
3124    FieldTypes[0] = getPointerType(IntTy.withConst());
3125    // const char *str;
3126    FieldTypes[1] = getPointerType(CharTy.withConst());
3127    // unsigned int length;
3128    FieldTypes[2] = UnsignedIntTy;
3129
3130    // Create fields
3131    for (unsigned i = 0; i < 3; ++i) {
3132      FieldDecl *Field = FieldDecl::Create(*this, NSConstantStringTypeDecl,
3133                                           SourceLocation(), 0,
3134                                           FieldTypes[i], /*TInfo=*/0,
3135                                           /*BitWidth=*/0,
3136                                           /*Mutable=*/false);
3137      Field->setAccess(AS_public);
3138      NSConstantStringTypeDecl->addDecl(Field);
3139    }
3140
3141    NSConstantStringTypeDecl->completeDefinition();
3142  }
3143
3144  return getTagDeclType(NSConstantStringTypeDecl);
3145}
3146
3147void ASTContext::setNSConstantStringType(QualType T) {
3148  const RecordType *Rec = T->getAs<RecordType>();
3149  assert(Rec && "Invalid NSConstantStringType");
3150  NSConstantStringTypeDecl = Rec->getDecl();
3151}
3152
3153QualType ASTContext::getObjCFastEnumerationStateType() {
3154  if (!ObjCFastEnumerationStateTypeDecl) {
3155    ObjCFastEnumerationStateTypeDecl =
3156      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3157                       &Idents.get("__objcFastEnumerationState"));
3158    ObjCFastEnumerationStateTypeDecl->startDefinition();
3159
3160    QualType FieldTypes[] = {
3161      UnsignedLongTy,
3162      getPointerType(ObjCIdTypedefType),
3163      getPointerType(UnsignedLongTy),
3164      getConstantArrayType(UnsignedLongTy,
3165                           llvm::APInt(32, 5), ArrayType::Normal, 0)
3166    };
3167
3168    for (size_t i = 0; i < 4; ++i) {
3169      FieldDecl *Field = FieldDecl::Create(*this,
3170                                           ObjCFastEnumerationStateTypeDecl,
3171                                           SourceLocation(), 0,
3172                                           FieldTypes[i], /*TInfo=*/0,
3173                                           /*BitWidth=*/0,
3174                                           /*Mutable=*/false);
3175      Field->setAccess(AS_public);
3176      ObjCFastEnumerationStateTypeDecl->addDecl(Field);
3177    }
3178
3179    ObjCFastEnumerationStateTypeDecl->completeDefinition();
3180  }
3181
3182  return getTagDeclType(ObjCFastEnumerationStateTypeDecl);
3183}
3184
3185QualType ASTContext::getBlockDescriptorType() {
3186  if (BlockDescriptorType)
3187    return getTagDeclType(BlockDescriptorType);
3188
3189  RecordDecl *T;
3190  // FIXME: Needs the FlagAppleBlock bit.
3191  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3192                       &Idents.get("__block_descriptor"));
3193  T->startDefinition();
3194
3195  QualType FieldTypes[] = {
3196    UnsignedLongTy,
3197    UnsignedLongTy,
3198  };
3199
3200  const char *FieldNames[] = {
3201    "reserved",
3202    "Size"
3203  };
3204
3205  for (size_t i = 0; i < 2; ++i) {
3206    FieldDecl *Field = FieldDecl::Create(*this,
3207                                         T,
3208                                         SourceLocation(),
3209                                         &Idents.get(FieldNames[i]),
3210                                         FieldTypes[i], /*TInfo=*/0,
3211                                         /*BitWidth=*/0,
3212                                         /*Mutable=*/false);
3213    Field->setAccess(AS_public);
3214    T->addDecl(Field);
3215  }
3216
3217  T->completeDefinition();
3218
3219  BlockDescriptorType = T;
3220
3221  return getTagDeclType(BlockDescriptorType);
3222}
3223
3224void ASTContext::setBlockDescriptorType(QualType T) {
3225  const RecordType *Rec = T->getAs<RecordType>();
3226  assert(Rec && "Invalid BlockDescriptorType");
3227  BlockDescriptorType = Rec->getDecl();
3228}
3229
3230QualType ASTContext::getBlockDescriptorExtendedType() {
3231  if (BlockDescriptorExtendedType)
3232    return getTagDeclType(BlockDescriptorExtendedType);
3233
3234  RecordDecl *T;
3235  // FIXME: Needs the FlagAppleBlock bit.
3236  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3237                       &Idents.get("__block_descriptor_withcopydispose"));
3238  T->startDefinition();
3239
3240  QualType FieldTypes[] = {
3241    UnsignedLongTy,
3242    UnsignedLongTy,
3243    getPointerType(VoidPtrTy),
3244    getPointerType(VoidPtrTy)
3245  };
3246
3247  const char *FieldNames[] = {
3248    "reserved",
3249    "Size",
3250    "CopyFuncPtr",
3251    "DestroyFuncPtr"
3252  };
3253
3254  for (size_t i = 0; i < 4; ++i) {
3255    FieldDecl *Field = FieldDecl::Create(*this,
3256                                         T,
3257                                         SourceLocation(),
3258                                         &Idents.get(FieldNames[i]),
3259                                         FieldTypes[i], /*TInfo=*/0,
3260                                         /*BitWidth=*/0,
3261                                         /*Mutable=*/false);
3262    Field->setAccess(AS_public);
3263    T->addDecl(Field);
3264  }
3265
3266  T->completeDefinition();
3267
3268  BlockDescriptorExtendedType = T;
3269
3270  return getTagDeclType(BlockDescriptorExtendedType);
3271}
3272
3273void ASTContext::setBlockDescriptorExtendedType(QualType T) {
3274  const RecordType *Rec = T->getAs<RecordType>();
3275  assert(Rec && "Invalid BlockDescriptorType");
3276  BlockDescriptorExtendedType = Rec->getDecl();
3277}
3278
3279bool ASTContext::BlockRequiresCopying(QualType Ty) {
3280  if (Ty->isBlockPointerType())
3281    return true;
3282  if (isObjCNSObjectType(Ty))
3283    return true;
3284  if (Ty->isObjCObjectPointerType())
3285    return true;
3286  return false;
3287}
3288
3289QualType ASTContext::BuildByRefType(llvm::StringRef DeclName, QualType Ty) {
3290  //  type = struct __Block_byref_1_X {
3291  //    void *__isa;
3292  //    struct __Block_byref_1_X *__forwarding;
3293  //    unsigned int __flags;
3294  //    unsigned int __size;
3295  //    void *__copy_helper;            // as needed
3296  //    void *__destroy_help            // as needed
3297  //    int X;
3298  //  } *
3299
3300  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3301
3302  // FIXME: Move up
3303  llvm::SmallString<36> Name;
3304  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3305                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3306  RecordDecl *T;
3307  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3308                       &Idents.get(Name.str()));
3309  T->startDefinition();
3310  QualType Int32Ty = IntTy;
3311  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3312  QualType FieldTypes[] = {
3313    getPointerType(VoidPtrTy),
3314    getPointerType(getTagDeclType(T)),
3315    Int32Ty,
3316    Int32Ty,
3317    getPointerType(VoidPtrTy),
3318    getPointerType(VoidPtrTy),
3319    Ty
3320  };
3321
3322  llvm::StringRef FieldNames[] = {
3323    "__isa",
3324    "__forwarding",
3325    "__flags",
3326    "__size",
3327    "__copy_helper",
3328    "__destroy_helper",
3329    DeclName,
3330  };
3331
3332  for (size_t i = 0; i < 7; ++i) {
3333    if (!HasCopyAndDispose && i >=4 && i <= 5)
3334      continue;
3335    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3336                                         &Idents.get(FieldNames[i]),
3337                                         FieldTypes[i], /*TInfo=*/0,
3338                                         /*BitWidth=*/0, /*Mutable=*/false);
3339    Field->setAccess(AS_public);
3340    T->addDecl(Field);
3341  }
3342
3343  T->completeDefinition();
3344
3345  return getPointerType(getTagDeclType(T));
3346}
3347
3348
3349QualType ASTContext::getBlockParmType(
3350  bool BlockHasCopyDispose,
3351  llvm::SmallVectorImpl<const Expr *> &Layout) {
3352
3353  // FIXME: Move up
3354  llvm::SmallString<36> Name;
3355  llvm::raw_svector_ostream(Name) << "__block_literal_"
3356                                  << ++UniqueBlockParmTypeID;
3357  RecordDecl *T;
3358  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3359                       &Idents.get(Name.str()));
3360  T->startDefinition();
3361  QualType FieldTypes[] = {
3362    getPointerType(VoidPtrTy),
3363    IntTy,
3364    IntTy,
3365    getPointerType(VoidPtrTy),
3366    (BlockHasCopyDispose ?
3367     getPointerType(getBlockDescriptorExtendedType()) :
3368     getPointerType(getBlockDescriptorType()))
3369  };
3370
3371  const char *FieldNames[] = {
3372    "__isa",
3373    "__flags",
3374    "__reserved",
3375    "__FuncPtr",
3376    "__descriptor"
3377  };
3378
3379  for (size_t i = 0; i < 5; ++i) {
3380    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3381                                         &Idents.get(FieldNames[i]),
3382                                         FieldTypes[i], /*TInfo=*/0,
3383                                         /*BitWidth=*/0, /*Mutable=*/false);
3384    Field->setAccess(AS_public);
3385    T->addDecl(Field);
3386  }
3387
3388  for (unsigned i = 0; i < Layout.size(); ++i) {
3389    const Expr *E = Layout[i];
3390
3391    QualType FieldType = E->getType();
3392    IdentifierInfo *FieldName = 0;
3393    if (isa<CXXThisExpr>(E)) {
3394      FieldName = &Idents.get("this");
3395    } else if (const BlockDeclRefExpr *BDRE = dyn_cast<BlockDeclRefExpr>(E)) {
3396      const ValueDecl *D = BDRE->getDecl();
3397      FieldName = D->getIdentifier();
3398      if (BDRE->isByRef())
3399        FieldType = BuildByRefType(D->getName(), FieldType);
3400    } else {
3401      // Padding.
3402      assert(isa<ConstantArrayType>(FieldType) &&
3403             isa<DeclRefExpr>(E) &&
3404             !cast<DeclRefExpr>(E)->getDecl()->getDeclName() &&
3405             "doesn't match characteristics of padding decl");
3406    }
3407
3408    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3409                                         FieldName, FieldType, /*TInfo=*/0,
3410                                         /*BitWidth=*/0, /*Mutable=*/false);
3411    Field->setAccess(AS_public);
3412    T->addDecl(Field);
3413  }
3414
3415  T->completeDefinition();
3416
3417  return getPointerType(getTagDeclType(T));
3418}
3419
3420void ASTContext::setObjCFastEnumerationStateType(QualType T) {
3421  const RecordType *Rec = T->getAs<RecordType>();
3422  assert(Rec && "Invalid ObjCFAstEnumerationStateType");
3423  ObjCFastEnumerationStateTypeDecl = Rec->getDecl();
3424}
3425
3426// This returns true if a type has been typedefed to BOOL:
3427// typedef <type> BOOL;
3428static bool isTypeTypedefedAsBOOL(QualType T) {
3429  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3430    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3431      return II->isStr("BOOL");
3432
3433  return false;
3434}
3435
3436/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3437/// purpose.
3438CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) {
3439  CharUnits sz = getTypeSizeInChars(type);
3440
3441  // Make all integer and enum types at least as large as an int
3442  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3443    sz = std::max(sz, getTypeSizeInChars(IntTy));
3444  // Treat arrays as pointers, since that's how they're passed in.
3445  else if (type->isArrayType())
3446    sz = getTypeSizeInChars(VoidPtrTy);
3447  return sz;
3448}
3449
3450static inline
3451std::string charUnitsToString(const CharUnits &CU) {
3452  return llvm::itostr(CU.getQuantity());
3453}
3454
3455/// getObjCEncodingForBlockDecl - Return the encoded type for this block
3456/// declaration.
3457void ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr,
3458                                             std::string& S) {
3459  const BlockDecl *Decl = Expr->getBlockDecl();
3460  QualType BlockTy =
3461      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3462  // Encode result type.
3463  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3464  // Compute size of all parameters.
3465  // Start with computing size of a pointer in number of bytes.
3466  // FIXME: There might(should) be a better way of doing this computation!
3467  SourceLocation Loc;
3468  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3469  CharUnits ParmOffset = PtrSize;
3470  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3471       E = Decl->param_end(); PI != E; ++PI) {
3472    QualType PType = (*PI)->getType();
3473    CharUnits sz = getObjCEncodingTypeSize(PType);
3474    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3475    ParmOffset += sz;
3476  }
3477  // Size of the argument frame
3478  S += charUnitsToString(ParmOffset);
3479  // Block pointer and offset.
3480  S += "@?0";
3481  ParmOffset = PtrSize;
3482
3483  // Argument types.
3484  ParmOffset = PtrSize;
3485  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3486       Decl->param_end(); PI != E; ++PI) {
3487    ParmVarDecl *PVDecl = *PI;
3488    QualType PType = PVDecl->getOriginalType();
3489    if (const ArrayType *AT =
3490          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3491      // Use array's original type only if it has known number of
3492      // elements.
3493      if (!isa<ConstantArrayType>(AT))
3494        PType = PVDecl->getType();
3495    } else if (PType->isFunctionType())
3496      PType = PVDecl->getType();
3497    getObjCEncodingForType(PType, S);
3498    S += charUnitsToString(ParmOffset);
3499    ParmOffset += getObjCEncodingTypeSize(PType);
3500  }
3501}
3502
3503/// getObjCEncodingForMethodDecl - Return the encoded type for this method
3504/// declaration.
3505void ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
3506                                              std::string& S) {
3507  // FIXME: This is not very efficient.
3508  // Encode type qualifer, 'in', 'inout', etc. for the return type.
3509  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
3510  // Encode result type.
3511  getObjCEncodingForType(Decl->getResultType(), S);
3512  // Compute size of all parameters.
3513  // Start with computing size of a pointer in number of bytes.
3514  // FIXME: There might(should) be a better way of doing this computation!
3515  SourceLocation Loc;
3516  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3517  // The first two arguments (self and _cmd) are pointers; account for
3518  // their size.
3519  CharUnits ParmOffset = 2 * PtrSize;
3520  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3521       E = Decl->sel_param_end(); PI != E; ++PI) {
3522    QualType PType = (*PI)->getType();
3523    CharUnits sz = getObjCEncodingTypeSize(PType);
3524    assert (sz.isPositive() &&
3525        "getObjCEncodingForMethodDecl - Incomplete param type");
3526    ParmOffset += sz;
3527  }
3528  S += charUnitsToString(ParmOffset);
3529  S += "@0:";
3530  S += charUnitsToString(PtrSize);
3531
3532  // Argument types.
3533  ParmOffset = 2 * PtrSize;
3534  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3535       E = Decl->sel_param_end(); PI != E; ++PI) {
3536    ParmVarDecl *PVDecl = *PI;
3537    QualType PType = PVDecl->getOriginalType();
3538    if (const ArrayType *AT =
3539          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3540      // Use array's original type only if it has known number of
3541      // elements.
3542      if (!isa<ConstantArrayType>(AT))
3543        PType = PVDecl->getType();
3544    } else if (PType->isFunctionType())
3545      PType = PVDecl->getType();
3546    // Process argument qualifiers for user supplied arguments; such as,
3547    // 'in', 'inout', etc.
3548    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
3549    getObjCEncodingForType(PType, S);
3550    S += charUnitsToString(ParmOffset);
3551    ParmOffset += getObjCEncodingTypeSize(PType);
3552  }
3553}
3554
3555/// getObjCEncodingForPropertyDecl - Return the encoded type for this
3556/// property declaration. If non-NULL, Container must be either an
3557/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
3558/// NULL when getting encodings for protocol properties.
3559/// Property attributes are stored as a comma-delimited C string. The simple
3560/// attributes readonly and bycopy are encoded as single characters. The
3561/// parametrized attributes, getter=name, setter=name, and ivar=name, are
3562/// encoded as single characters, followed by an identifier. Property types
3563/// are also encoded as a parametrized attribute. The characters used to encode
3564/// these attributes are defined by the following enumeration:
3565/// @code
3566/// enum PropertyAttributes {
3567/// kPropertyReadOnly = 'R',   // property is read-only.
3568/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
3569/// kPropertyByref = '&',  // property is a reference to the value last assigned
3570/// kPropertyDynamic = 'D',    // property is dynamic
3571/// kPropertyGetter = 'G',     // followed by getter selector name
3572/// kPropertySetter = 'S',     // followed by setter selector name
3573/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
3574/// kPropertyType = 't'              // followed by old-style type encoding.
3575/// kPropertyWeak = 'W'              // 'weak' property
3576/// kPropertyStrong = 'P'            // property GC'able
3577/// kPropertyNonAtomic = 'N'         // property non-atomic
3578/// };
3579/// @endcode
3580void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
3581                                                const Decl *Container,
3582                                                std::string& S) {
3583  // Collect information from the property implementation decl(s).
3584  bool Dynamic = false;
3585  ObjCPropertyImplDecl *SynthesizePID = 0;
3586
3587  // FIXME: Duplicated code due to poor abstraction.
3588  if (Container) {
3589    if (const ObjCCategoryImplDecl *CID =
3590        dyn_cast<ObjCCategoryImplDecl>(Container)) {
3591      for (ObjCCategoryImplDecl::propimpl_iterator
3592             i = CID->propimpl_begin(), e = CID->propimpl_end();
3593           i != e; ++i) {
3594        ObjCPropertyImplDecl *PID = *i;
3595        if (PID->getPropertyDecl() == PD) {
3596          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3597            Dynamic = true;
3598          } else {
3599            SynthesizePID = PID;
3600          }
3601        }
3602      }
3603    } else {
3604      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
3605      for (ObjCCategoryImplDecl::propimpl_iterator
3606             i = OID->propimpl_begin(), e = OID->propimpl_end();
3607           i != e; ++i) {
3608        ObjCPropertyImplDecl *PID = *i;
3609        if (PID->getPropertyDecl() == PD) {
3610          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3611            Dynamic = true;
3612          } else {
3613            SynthesizePID = PID;
3614          }
3615        }
3616      }
3617    }
3618  }
3619
3620  // FIXME: This is not very efficient.
3621  S = "T";
3622
3623  // Encode result type.
3624  // GCC has some special rules regarding encoding of properties which
3625  // closely resembles encoding of ivars.
3626  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
3627                             true /* outermost type */,
3628                             true /* encoding for property */);
3629
3630  if (PD->isReadOnly()) {
3631    S += ",R";
3632  } else {
3633    switch (PD->getSetterKind()) {
3634    case ObjCPropertyDecl::Assign: break;
3635    case ObjCPropertyDecl::Copy:   S += ",C"; break;
3636    case ObjCPropertyDecl::Retain: S += ",&"; break;
3637    }
3638  }
3639
3640  // It really isn't clear at all what this means, since properties
3641  // are "dynamic by default".
3642  if (Dynamic)
3643    S += ",D";
3644
3645  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
3646    S += ",N";
3647
3648  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
3649    S += ",G";
3650    S += PD->getGetterName().getAsString();
3651  }
3652
3653  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
3654    S += ",S";
3655    S += PD->getSetterName().getAsString();
3656  }
3657
3658  if (SynthesizePID) {
3659    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
3660    S += ",V";
3661    S += OID->getNameAsString();
3662  }
3663
3664  // FIXME: OBJCGC: weak & strong
3665}
3666
3667/// getLegacyIntegralTypeEncoding -
3668/// Another legacy compatibility encoding: 32-bit longs are encoded as
3669/// 'l' or 'L' , but not always.  For typedefs, we need to use
3670/// 'i' or 'I' instead if encoding a struct field, or a pointer!
3671///
3672void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
3673  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
3674    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
3675      if (BT->getKind() == BuiltinType::ULong &&
3676          ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3677        PointeeTy = UnsignedIntTy;
3678      else
3679        if (BT->getKind() == BuiltinType::Long &&
3680            ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3681          PointeeTy = IntTy;
3682    }
3683  }
3684}
3685
3686void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
3687                                        const FieldDecl *Field) {
3688  // We follow the behavior of gcc, expanding structures which are
3689  // directly pointed to, and expanding embedded structures. Note that
3690  // these rules are sufficient to prevent recursive encoding of the
3691  // same type.
3692  getObjCEncodingForTypeImpl(T, S, true, true, Field,
3693                             true /* outermost type */);
3694}
3695
3696static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
3697    switch (T->getAs<BuiltinType>()->getKind()) {
3698    default: assert(0 && "Unhandled builtin type kind");
3699    case BuiltinType::Void:       return 'v';
3700    case BuiltinType::Bool:       return 'B';
3701    case BuiltinType::Char_U:
3702    case BuiltinType::UChar:      return 'C';
3703    case BuiltinType::UShort:     return 'S';
3704    case BuiltinType::UInt:       return 'I';
3705    case BuiltinType::ULong:
3706        return
3707          (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'L' : 'Q';
3708    case BuiltinType::UInt128:    return 'T';
3709    case BuiltinType::ULongLong:  return 'Q';
3710    case BuiltinType::Char_S:
3711    case BuiltinType::SChar:      return 'c';
3712    case BuiltinType::Short:      return 's';
3713    case BuiltinType::WChar:
3714    case BuiltinType::Int:        return 'i';
3715    case BuiltinType::Long:
3716      return
3717        (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'l' : 'q';
3718    case BuiltinType::LongLong:   return 'q';
3719    case BuiltinType::Int128:     return 't';
3720    case BuiltinType::Float:      return 'f';
3721    case BuiltinType::Double:     return 'd';
3722    case BuiltinType::LongDouble: return 'D';
3723    }
3724}
3725
3726static void EncodeBitField(const ASTContext *Context, std::string& S,
3727                           QualType T, const FieldDecl *FD) {
3728  const Expr *E = FD->getBitWidth();
3729  assert(E && "bitfield width not there - getObjCEncodingForTypeImpl");
3730  ASTContext *Ctx = const_cast<ASTContext*>(Context);
3731  S += 'b';
3732  // The NeXT runtime encodes bit fields as b followed by the number of bits.
3733  // The GNU runtime requires more information; bitfields are encoded as b,
3734  // then the offset (in bits) of the first element, then the type of the
3735  // bitfield, then the size in bits.  For example, in this structure:
3736  //
3737  // struct
3738  // {
3739  //    int integer;
3740  //    int flags:2;
3741  // };
3742  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
3743  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
3744  // information is not especially sensible, but we're stuck with it for
3745  // compatibility with GCC, although providing it breaks anything that
3746  // actually uses runtime introspection and wants to work on both runtimes...
3747  if (!Ctx->getLangOptions().NeXTRuntime) {
3748    const RecordDecl *RD = FD->getParent();
3749    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
3750    // FIXME: This same linear search is also used in ExprConstant - it might
3751    // be better if the FieldDecl stored its offset.  We'd be increasing the
3752    // size of the object slightly, but saving some time every time it is used.
3753    unsigned i = 0;
3754    for (RecordDecl::field_iterator Field = RD->field_begin(),
3755                                 FieldEnd = RD->field_end();
3756         Field != FieldEnd; (void)++Field, ++i) {
3757      if (*Field == FD)
3758        break;
3759    }
3760    S += llvm::utostr(RL.getFieldOffset(i));
3761    S += ObjCEncodingForPrimitiveKind(Context, T);
3762  }
3763  unsigned N = E->EvaluateAsInt(*Ctx).getZExtValue();
3764  S += llvm::utostr(N);
3765}
3766
3767// FIXME: Use SmallString for accumulating string.
3768void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
3769                                            bool ExpandPointedToStructures,
3770                                            bool ExpandStructures,
3771                                            const FieldDecl *FD,
3772                                            bool OutermostType,
3773                                            bool EncodingProperty) {
3774  if (T->getAs<BuiltinType>()) {
3775    if (FD && FD->isBitField())
3776      return EncodeBitField(this, S, T, FD);
3777    S += ObjCEncodingForPrimitiveKind(this, T);
3778    return;
3779  }
3780
3781  if (const ComplexType *CT = T->getAs<ComplexType>()) {
3782    S += 'j';
3783    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
3784                               false);
3785    return;
3786  }
3787
3788  // encoding for pointer or r3eference types.
3789  QualType PointeeTy;
3790  if (const PointerType *PT = T->getAs<PointerType>()) {
3791    if (PT->isObjCSelType()) {
3792      S += ':';
3793      return;
3794    }
3795    PointeeTy = PT->getPointeeType();
3796  }
3797  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3798    PointeeTy = RT->getPointeeType();
3799  if (!PointeeTy.isNull()) {
3800    bool isReadOnly = false;
3801    // For historical/compatibility reasons, the read-only qualifier of the
3802    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
3803    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
3804    // Also, do not emit the 'r' for anything but the outermost type!
3805    if (isa<TypedefType>(T.getTypePtr())) {
3806      if (OutermostType && T.isConstQualified()) {
3807        isReadOnly = true;
3808        S += 'r';
3809      }
3810    } else if (OutermostType) {
3811      QualType P = PointeeTy;
3812      while (P->getAs<PointerType>())
3813        P = P->getAs<PointerType>()->getPointeeType();
3814      if (P.isConstQualified()) {
3815        isReadOnly = true;
3816        S += 'r';
3817      }
3818    }
3819    if (isReadOnly) {
3820      // Another legacy compatibility encoding. Some ObjC qualifier and type
3821      // combinations need to be rearranged.
3822      // Rewrite "in const" from "nr" to "rn"
3823      if (llvm::StringRef(S).endswith("nr"))
3824        S.replace(S.end()-2, S.end(), "rn");
3825    }
3826
3827    if (PointeeTy->isCharType()) {
3828      // char pointer types should be encoded as '*' unless it is a
3829      // type that has been typedef'd to 'BOOL'.
3830      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
3831        S += '*';
3832        return;
3833      }
3834    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
3835      // GCC binary compat: Need to convert "struct objc_class *" to "#".
3836      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
3837        S += '#';
3838        return;
3839      }
3840      // GCC binary compat: Need to convert "struct objc_object *" to "@".
3841      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
3842        S += '@';
3843        return;
3844      }
3845      // fall through...
3846    }
3847    S += '^';
3848    getLegacyIntegralTypeEncoding(PointeeTy);
3849
3850    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
3851                               NULL);
3852    return;
3853  }
3854
3855  if (const ArrayType *AT =
3856      // Ignore type qualifiers etc.
3857        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
3858    if (isa<IncompleteArrayType>(AT)) {
3859      // Incomplete arrays are encoded as a pointer to the array element.
3860      S += '^';
3861
3862      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3863                                 false, ExpandStructures, FD);
3864    } else {
3865      S += '[';
3866
3867      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
3868        S += llvm::utostr(CAT->getSize().getZExtValue());
3869      else {
3870        //Variable length arrays are encoded as a regular array with 0 elements.
3871        assert(isa<VariableArrayType>(AT) && "Unknown array type!");
3872        S += '0';
3873      }
3874
3875      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3876                                 false, ExpandStructures, FD);
3877      S += ']';
3878    }
3879    return;
3880  }
3881
3882  if (T->getAs<FunctionType>()) {
3883    S += '?';
3884    return;
3885  }
3886
3887  if (const RecordType *RTy = T->getAs<RecordType>()) {
3888    RecordDecl *RDecl = RTy->getDecl();
3889    S += RDecl->isUnion() ? '(' : '{';
3890    // Anonymous structures print as '?'
3891    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
3892      S += II->getName();
3893      if (ClassTemplateSpecializationDecl *Spec
3894          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
3895        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
3896        std::string TemplateArgsStr
3897          = TemplateSpecializationType::PrintTemplateArgumentList(
3898                                            TemplateArgs.data(),
3899                                            TemplateArgs.size(),
3900                                            (*this).PrintingPolicy);
3901
3902        S += TemplateArgsStr;
3903      }
3904    } else {
3905      S += '?';
3906    }
3907    if (ExpandStructures) {
3908      S += '=';
3909      for (RecordDecl::field_iterator Field = RDecl->field_begin(),
3910                                   FieldEnd = RDecl->field_end();
3911           Field != FieldEnd; ++Field) {
3912        if (FD) {
3913          S += '"';
3914          S += Field->getNameAsString();
3915          S += '"';
3916        }
3917
3918        // Special case bit-fields.
3919        if (Field->isBitField()) {
3920          getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
3921                                     (*Field));
3922        } else {
3923          QualType qt = Field->getType();
3924          getLegacyIntegralTypeEncoding(qt);
3925          getObjCEncodingForTypeImpl(qt, S, false, true,
3926                                     FD);
3927        }
3928      }
3929    }
3930    S += RDecl->isUnion() ? ')' : '}';
3931    return;
3932  }
3933
3934  if (T->isEnumeralType()) {
3935    if (FD && FD->isBitField())
3936      EncodeBitField(this, S, T, FD);
3937    else
3938      S += 'i';
3939    return;
3940  }
3941
3942  if (T->isBlockPointerType()) {
3943    S += "@?"; // Unlike a pointer-to-function, which is "^?".
3944    return;
3945  }
3946
3947  // Ignore protocol qualifiers when mangling at this level.
3948  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
3949    T = OT->getBaseType();
3950
3951  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
3952    // @encode(class_name)
3953    ObjCInterfaceDecl *OI = OIT->getDecl();
3954    S += '{';
3955    const IdentifierInfo *II = OI->getIdentifier();
3956    S += II->getName();
3957    S += '=';
3958    llvm::SmallVector<ObjCIvarDecl*, 32> Ivars;
3959    DeepCollectObjCIvars(OI, true, Ivars);
3960    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
3961      FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
3962      if (Field->isBitField())
3963        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
3964      else
3965        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
3966    }
3967    S += '}';
3968    return;
3969  }
3970
3971  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
3972    if (OPT->isObjCIdType()) {
3973      S += '@';
3974      return;
3975    }
3976
3977    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
3978      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
3979      // Since this is a binary compatibility issue, need to consult with runtime
3980      // folks. Fortunately, this is a *very* obsure construct.
3981      S += '#';
3982      return;
3983    }
3984
3985    if (OPT->isObjCQualifiedIdType()) {
3986      getObjCEncodingForTypeImpl(getObjCIdType(), S,
3987                                 ExpandPointedToStructures,
3988                                 ExpandStructures, FD);
3989      if (FD || EncodingProperty) {
3990        // Note that we do extended encoding of protocol qualifer list
3991        // Only when doing ivar or property encoding.
3992        S += '"';
3993        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3994             E = OPT->qual_end(); I != E; ++I) {
3995          S += '<';
3996          S += (*I)->getNameAsString();
3997          S += '>';
3998        }
3999        S += '"';
4000      }
4001      return;
4002    }
4003
4004    QualType PointeeTy = OPT->getPointeeType();
4005    if (!EncodingProperty &&
4006        isa<TypedefType>(PointeeTy.getTypePtr())) {
4007      // Another historical/compatibility reason.
4008      // We encode the underlying type which comes out as
4009      // {...};
4010      S += '^';
4011      getObjCEncodingForTypeImpl(PointeeTy, S,
4012                                 false, ExpandPointedToStructures,
4013                                 NULL);
4014      return;
4015    }
4016
4017    S += '@';
4018    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
4019      S += '"';
4020      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4021      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4022           E = OPT->qual_end(); I != E; ++I) {
4023        S += '<';
4024        S += (*I)->getNameAsString();
4025        S += '>';
4026      }
4027      S += '"';
4028    }
4029    return;
4030  }
4031
4032  // gcc just blithely ignores member pointers.
4033  // TODO: maybe there should be a mangling for these
4034  if (T->getAs<MemberPointerType>())
4035    return;
4036
4037  if (T->isVectorType()) {
4038    // This matches gcc's encoding, even though technically it is
4039    // insufficient.
4040    // FIXME. We should do a better job than gcc.
4041    return;
4042  }
4043
4044  assert(0 && "@encode for type not implemented!");
4045}
4046
4047void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4048                                                 std::string& S) const {
4049  if (QT & Decl::OBJC_TQ_In)
4050    S += 'n';
4051  if (QT & Decl::OBJC_TQ_Inout)
4052    S += 'N';
4053  if (QT & Decl::OBJC_TQ_Out)
4054    S += 'o';
4055  if (QT & Decl::OBJC_TQ_Bycopy)
4056    S += 'O';
4057  if (QT & Decl::OBJC_TQ_Byref)
4058    S += 'R';
4059  if (QT & Decl::OBJC_TQ_Oneway)
4060    S += 'V';
4061}
4062
4063void ASTContext::setBuiltinVaListType(QualType T) {
4064  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4065
4066  BuiltinVaListType = T;
4067}
4068
4069void ASTContext::setObjCIdType(QualType T) {
4070  ObjCIdTypedefType = T;
4071}
4072
4073void ASTContext::setObjCSelType(QualType T) {
4074  ObjCSelTypedefType = T;
4075}
4076
4077void ASTContext::setObjCProtoType(QualType QT) {
4078  ObjCProtoType = QT;
4079}
4080
4081void ASTContext::setObjCClassType(QualType T) {
4082  ObjCClassTypedefType = T;
4083}
4084
4085void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4086  assert(ObjCConstantStringType.isNull() &&
4087         "'NSConstantString' type already set!");
4088
4089  ObjCConstantStringType = getObjCInterfaceType(Decl);
4090}
4091
4092/// \brief Retrieve the template name that corresponds to a non-empty
4093/// lookup.
4094TemplateName ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4095                                                   UnresolvedSetIterator End) {
4096  unsigned size = End - Begin;
4097  assert(size > 1 && "set is not overloaded!");
4098
4099  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4100                          size * sizeof(FunctionTemplateDecl*));
4101  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4102
4103  NamedDecl **Storage = OT->getStorage();
4104  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4105    NamedDecl *D = *I;
4106    assert(isa<FunctionTemplateDecl>(D) ||
4107           (isa<UsingShadowDecl>(D) &&
4108            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4109    *Storage++ = D;
4110  }
4111
4112  return TemplateName(OT);
4113}
4114
4115/// \brief Retrieve the template name that represents a qualified
4116/// template name such as \c std::vector.
4117TemplateName ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4118                                                  bool TemplateKeyword,
4119                                                  TemplateDecl *Template) {
4120  // FIXME: Canonicalization?
4121  llvm::FoldingSetNodeID ID;
4122  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4123
4124  void *InsertPos = 0;
4125  QualifiedTemplateName *QTN =
4126    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4127  if (!QTN) {
4128    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4129    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4130  }
4131
4132  return TemplateName(QTN);
4133}
4134
4135/// \brief Retrieve the template name that represents a dependent
4136/// template name such as \c MetaFun::template apply.
4137TemplateName ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4138                                                  const IdentifierInfo *Name) {
4139  assert((!NNS || NNS->isDependent()) &&
4140         "Nested name specifier must be dependent");
4141
4142  llvm::FoldingSetNodeID ID;
4143  DependentTemplateName::Profile(ID, NNS, Name);
4144
4145  void *InsertPos = 0;
4146  DependentTemplateName *QTN =
4147    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4148
4149  if (QTN)
4150    return TemplateName(QTN);
4151
4152  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4153  if (CanonNNS == NNS) {
4154    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4155  } else {
4156    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4157    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4158    DependentTemplateName *CheckQTN =
4159      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4160    assert(!CheckQTN && "Dependent type name canonicalization broken");
4161    (void)CheckQTN;
4162  }
4163
4164  DependentTemplateNames.InsertNode(QTN, InsertPos);
4165  return TemplateName(QTN);
4166}
4167
4168/// \brief Retrieve the template name that represents a dependent
4169/// template name such as \c MetaFun::template operator+.
4170TemplateName
4171ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4172                                     OverloadedOperatorKind Operator) {
4173  assert((!NNS || NNS->isDependent()) &&
4174         "Nested name specifier must be dependent");
4175
4176  llvm::FoldingSetNodeID ID;
4177  DependentTemplateName::Profile(ID, NNS, Operator);
4178
4179  void *InsertPos = 0;
4180  DependentTemplateName *QTN
4181    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4182
4183  if (QTN)
4184    return TemplateName(QTN);
4185
4186  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4187  if (CanonNNS == NNS) {
4188    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4189  } else {
4190    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4191    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4192
4193    DependentTemplateName *CheckQTN
4194      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4195    assert(!CheckQTN && "Dependent template name canonicalization broken");
4196    (void)CheckQTN;
4197  }
4198
4199  DependentTemplateNames.InsertNode(QTN, InsertPos);
4200  return TemplateName(QTN);
4201}
4202
4203/// getFromTargetType - Given one of the integer types provided by
4204/// TargetInfo, produce the corresponding type. The unsigned @p Type
4205/// is actually a value of type @c TargetInfo::IntType.
4206CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4207  switch (Type) {
4208  case TargetInfo::NoInt: return CanQualType();
4209  case TargetInfo::SignedShort: return ShortTy;
4210  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4211  case TargetInfo::SignedInt: return IntTy;
4212  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4213  case TargetInfo::SignedLong: return LongTy;
4214  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4215  case TargetInfo::SignedLongLong: return LongLongTy;
4216  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4217  }
4218
4219  assert(false && "Unhandled TargetInfo::IntType value");
4220  return CanQualType();
4221}
4222
4223//===----------------------------------------------------------------------===//
4224//                        Type Predicates.
4225//===----------------------------------------------------------------------===//
4226
4227/// isObjCNSObjectType - Return true if this is an NSObject object using
4228/// NSObject attribute on a c-style pointer type.
4229/// FIXME - Make it work directly on types.
4230/// FIXME: Move to Type.
4231///
4232bool ASTContext::isObjCNSObjectType(QualType Ty) const {
4233  if (TypedefType *TDT = dyn_cast<TypedefType>(Ty)) {
4234    if (TypedefDecl *TD = TDT->getDecl())
4235      if (TD->getAttr<ObjCNSObjectAttr>())
4236        return true;
4237  }
4238  return false;
4239}
4240
4241/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4242/// garbage collection attribute.
4243///
4244Qualifiers::GC ASTContext::getObjCGCAttrKind(const QualType &Ty) const {
4245  Qualifiers::GC GCAttrs = Qualifiers::GCNone;
4246  if (getLangOptions().ObjC1 &&
4247      getLangOptions().getGCMode() != LangOptions::NonGC) {
4248    GCAttrs = Ty.getObjCGCAttr();
4249    // Default behavious under objective-c's gc is for objective-c pointers
4250    // (or pointers to them) be treated as though they were declared
4251    // as __strong.
4252    if (GCAttrs == Qualifiers::GCNone) {
4253      if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4254        GCAttrs = Qualifiers::Strong;
4255      else if (Ty->isPointerType())
4256        return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4257    }
4258    // Non-pointers have none gc'able attribute regardless of the attribute
4259    // set on them.
4260    else if (!Ty->isAnyPointerType() && !Ty->isBlockPointerType())
4261      return Qualifiers::GCNone;
4262  }
4263  return GCAttrs;
4264}
4265
4266//===----------------------------------------------------------------------===//
4267//                        Type Compatibility Testing
4268//===----------------------------------------------------------------------===//
4269
4270/// areCompatVectorTypes - Return true if the two specified vector types are
4271/// compatible.
4272static bool areCompatVectorTypes(const VectorType *LHS,
4273                                 const VectorType *RHS) {
4274  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
4275  return LHS->getElementType() == RHS->getElementType() &&
4276         LHS->getNumElements() == RHS->getNumElements();
4277}
4278
4279bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
4280                                          QualType SecondVec) {
4281  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
4282  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
4283
4284  if (hasSameUnqualifiedType(FirstVec, SecondVec))
4285    return true;
4286
4287  // AltiVec vectors types are identical to equivalent GCC vector types
4288  const VectorType *First = FirstVec->getAs<VectorType>();
4289  const VectorType *Second = SecondVec->getAs<VectorType>();
4290  if ((((First->getAltiVecSpecific() == VectorType::AltiVec) &&
4291        (Second->getAltiVecSpecific() == VectorType::NotAltiVec)) ||
4292       ((First->getAltiVecSpecific() == VectorType::NotAltiVec) &&
4293        (Second->getAltiVecSpecific() == VectorType::AltiVec))) &&
4294      hasSameType(First->getElementType(), Second->getElementType()) &&
4295      (First->getNumElements() == Second->getNumElements()))
4296    return true;
4297
4298  return false;
4299}
4300
4301//===----------------------------------------------------------------------===//
4302// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
4303//===----------------------------------------------------------------------===//
4304
4305/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
4306/// inheritance hierarchy of 'rProto'.
4307bool ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
4308                                                ObjCProtocolDecl *rProto) {
4309  if (lProto == rProto)
4310    return true;
4311  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
4312       E = rProto->protocol_end(); PI != E; ++PI)
4313    if (ProtocolCompatibleWithProtocol(lProto, *PI))
4314      return true;
4315  return false;
4316}
4317
4318/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
4319/// return true if lhs's protocols conform to rhs's protocol; false
4320/// otherwise.
4321bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
4322  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
4323    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
4324  return false;
4325}
4326
4327/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
4328/// Class<p1, ...>.
4329bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
4330                                                      QualType rhs) {
4331  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
4332  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4333  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
4334
4335  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4336       E = lhsQID->qual_end(); I != E; ++I) {
4337    bool match = false;
4338    ObjCProtocolDecl *lhsProto = *I;
4339    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4340         E = rhsOPT->qual_end(); J != E; ++J) {
4341      ObjCProtocolDecl *rhsProto = *J;
4342      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
4343        match = true;
4344        break;
4345      }
4346    }
4347    if (!match)
4348      return false;
4349  }
4350  return true;
4351}
4352
4353/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
4354/// ObjCQualifiedIDType.
4355bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
4356                                                   bool compare) {
4357  // Allow id<P..> and an 'id' or void* type in all cases.
4358  if (lhs->isVoidPointerType() ||
4359      lhs->isObjCIdType() || lhs->isObjCClassType())
4360    return true;
4361  else if (rhs->isVoidPointerType() ||
4362           rhs->isObjCIdType() || rhs->isObjCClassType())
4363    return true;
4364
4365  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
4366    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4367
4368    if (!rhsOPT) return false;
4369
4370    if (rhsOPT->qual_empty()) {
4371      // If the RHS is a unqualified interface pointer "NSString*",
4372      // make sure we check the class hierarchy.
4373      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4374        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4375             E = lhsQID->qual_end(); I != E; ++I) {
4376          // when comparing an id<P> on lhs with a static type on rhs,
4377          // see if static class implements all of id's protocols, directly or
4378          // through its super class and categories.
4379          if (!rhsID->ClassImplementsProtocol(*I, true))
4380            return false;
4381        }
4382      }
4383      // If there are no qualifiers and no interface, we have an 'id'.
4384      return true;
4385    }
4386    // Both the right and left sides have qualifiers.
4387    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4388         E = lhsQID->qual_end(); I != E; ++I) {
4389      ObjCProtocolDecl *lhsProto = *I;
4390      bool match = false;
4391
4392      // when comparing an id<P> on lhs with a static type on rhs,
4393      // see if static class implements all of id's protocols, directly or
4394      // through its super class and categories.
4395      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4396           E = rhsOPT->qual_end(); J != E; ++J) {
4397        ObjCProtocolDecl *rhsProto = *J;
4398        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4399            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4400          match = true;
4401          break;
4402        }
4403      }
4404      // If the RHS is a qualified interface pointer "NSString<P>*",
4405      // make sure we check the class hierarchy.
4406      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4407        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4408             E = lhsQID->qual_end(); I != E; ++I) {
4409          // when comparing an id<P> on lhs with a static type on rhs,
4410          // see if static class implements all of id's protocols, directly or
4411          // through its super class and categories.
4412          if (rhsID->ClassImplementsProtocol(*I, true)) {
4413            match = true;
4414            break;
4415          }
4416        }
4417      }
4418      if (!match)
4419        return false;
4420    }
4421
4422    return true;
4423  }
4424
4425  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
4426  assert(rhsQID && "One of the LHS/RHS should be id<x>");
4427
4428  if (const ObjCObjectPointerType *lhsOPT =
4429        lhs->getAsObjCInterfacePointerType()) {
4430    // If both the right and left sides have qualifiers.
4431    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
4432         E = lhsOPT->qual_end(); I != E; ++I) {
4433      ObjCProtocolDecl *lhsProto = *I;
4434      bool match = false;
4435
4436      // when comparing an id<P> on rhs with a static type on lhs,
4437      // see if static class implements all of id's protocols, directly or
4438      // through its super class and categories.
4439      // First, lhs protocols in the qualifier list must be found, direct
4440      // or indirect in rhs's qualifier list or it is a mismatch.
4441      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4442           E = rhsQID->qual_end(); J != E; ++J) {
4443        ObjCProtocolDecl *rhsProto = *J;
4444        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4445            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4446          match = true;
4447          break;
4448        }
4449      }
4450      if (!match)
4451        return false;
4452    }
4453
4454    // Static class's protocols, or its super class or category protocols
4455    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
4456    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
4457      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4458      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
4459      // This is rather dubious but matches gcc's behavior. If lhs has
4460      // no type qualifier and its class has no static protocol(s)
4461      // assume that it is mismatch.
4462      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
4463        return false;
4464      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4465           LHSInheritedProtocols.begin(),
4466           E = LHSInheritedProtocols.end(); I != E; ++I) {
4467        bool match = false;
4468        ObjCProtocolDecl *lhsProto = (*I);
4469        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4470             E = rhsQID->qual_end(); J != E; ++J) {
4471          ObjCProtocolDecl *rhsProto = *J;
4472          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4473              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4474            match = true;
4475            break;
4476          }
4477        }
4478        if (!match)
4479          return false;
4480      }
4481    }
4482    return true;
4483  }
4484  return false;
4485}
4486
4487/// canAssignObjCInterfaces - Return true if the two interface types are
4488/// compatible for assignment from RHS to LHS.  This handles validation of any
4489/// protocol qualifiers on the LHS or RHS.
4490///
4491bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
4492                                         const ObjCObjectPointerType *RHSOPT) {
4493  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4494  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4495
4496  // If either type represents the built-in 'id' or 'Class' types, return true.
4497  if (LHS->isObjCUnqualifiedIdOrClass() ||
4498      RHS->isObjCUnqualifiedIdOrClass())
4499    return true;
4500
4501  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
4502    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4503                                             QualType(RHSOPT,0),
4504                                             false);
4505
4506  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
4507    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
4508                                                QualType(RHSOPT,0));
4509
4510  // If we have 2 user-defined types, fall into that path.
4511  if (LHS->getInterface() && RHS->getInterface())
4512    return canAssignObjCInterfaces(LHS, RHS);
4513
4514  return false;
4515}
4516
4517/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
4518/// for providing type-safty for objective-c pointers used to pass/return
4519/// arguments in block literals. When passed as arguments, passing 'A*' where
4520/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
4521/// not OK. For the return type, the opposite is not OK.
4522bool ASTContext::canAssignObjCInterfacesInBlockPointer(
4523                                         const ObjCObjectPointerType *LHSOPT,
4524                                         const ObjCObjectPointerType *RHSOPT) {
4525  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
4526    return true;
4527
4528  if (LHSOPT->isObjCBuiltinType()) {
4529    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
4530  }
4531
4532  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
4533    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4534                                             QualType(RHSOPT,0),
4535                                             false);
4536
4537  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
4538  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
4539  if (LHS && RHS)  { // We have 2 user-defined types.
4540    if (LHS != RHS) {
4541      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
4542        return false;
4543      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
4544        return true;
4545    }
4546    else
4547      return true;
4548  }
4549  return false;
4550}
4551
4552/// getIntersectionOfProtocols - This routine finds the intersection of set
4553/// of protocols inherited from two distinct objective-c pointer objects.
4554/// It is used to build composite qualifier list of the composite type of
4555/// the conditional expression involving two objective-c pointer objects.
4556static
4557void getIntersectionOfProtocols(ASTContext &Context,
4558                                const ObjCObjectPointerType *LHSOPT,
4559                                const ObjCObjectPointerType *RHSOPT,
4560      llvm::SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
4561
4562  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4563  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4564  assert(LHS->getInterface() && "LHS must have an interface base");
4565  assert(RHS->getInterface() && "RHS must have an interface base");
4566
4567  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
4568  unsigned LHSNumProtocols = LHS->getNumProtocols();
4569  if (LHSNumProtocols > 0)
4570    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
4571  else {
4572    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4573    Context.CollectInheritedProtocols(LHS->getInterface(),
4574                                      LHSInheritedProtocols);
4575    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
4576                                LHSInheritedProtocols.end());
4577  }
4578
4579  unsigned RHSNumProtocols = RHS->getNumProtocols();
4580  if (RHSNumProtocols > 0) {
4581    ObjCProtocolDecl **RHSProtocols =
4582      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
4583    for (unsigned i = 0; i < RHSNumProtocols; ++i)
4584      if (InheritedProtocolSet.count(RHSProtocols[i]))
4585        IntersectionOfProtocols.push_back(RHSProtocols[i]);
4586  }
4587  else {
4588    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
4589    Context.CollectInheritedProtocols(RHS->getInterface(),
4590                                      RHSInheritedProtocols);
4591    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4592         RHSInheritedProtocols.begin(),
4593         E = RHSInheritedProtocols.end(); I != E; ++I)
4594      if (InheritedProtocolSet.count((*I)))
4595        IntersectionOfProtocols.push_back((*I));
4596  }
4597}
4598
4599/// areCommonBaseCompatible - Returns common base class of the two classes if
4600/// one found. Note that this is O'2 algorithm. But it will be called as the
4601/// last type comparison in a ?-exp of ObjC pointer types before a
4602/// warning is issued. So, its invokation is extremely rare.
4603QualType ASTContext::areCommonBaseCompatible(
4604                                          const ObjCObjectPointerType *Lptr,
4605                                          const ObjCObjectPointerType *Rptr) {
4606  const ObjCObjectType *LHS = Lptr->getObjectType();
4607  const ObjCObjectType *RHS = Rptr->getObjectType();
4608  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
4609  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
4610  if (!LDecl || !RDecl)
4611    return QualType();
4612
4613  while ((LDecl = LDecl->getSuperClass())) {
4614    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
4615    if (canAssignObjCInterfaces(LHS, RHS)) {
4616      llvm::SmallVector<ObjCProtocolDecl *, 8> Protocols;
4617      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
4618
4619      QualType Result = QualType(LHS, 0);
4620      if (!Protocols.empty())
4621        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
4622      Result = getObjCObjectPointerType(Result);
4623      return Result;
4624    }
4625  }
4626
4627  return QualType();
4628}
4629
4630bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
4631                                         const ObjCObjectType *RHS) {
4632  assert(LHS->getInterface() && "LHS is not an interface type");
4633  assert(RHS->getInterface() && "RHS is not an interface type");
4634
4635  // Verify that the base decls are compatible: the RHS must be a subclass of
4636  // the LHS.
4637  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
4638    return false;
4639
4640  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
4641  // protocol qualified at all, then we are good.
4642  if (LHS->getNumProtocols() == 0)
4643    return true;
4644
4645  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't, then it
4646  // isn't a superset.
4647  if (RHS->getNumProtocols() == 0)
4648    return true;  // FIXME: should return false!
4649
4650  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
4651                                     LHSPE = LHS->qual_end();
4652       LHSPI != LHSPE; LHSPI++) {
4653    bool RHSImplementsProtocol = false;
4654
4655    // If the RHS doesn't implement the protocol on the left, the types
4656    // are incompatible.
4657    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
4658                                       RHSPE = RHS->qual_end();
4659         RHSPI != RHSPE; RHSPI++) {
4660      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
4661        RHSImplementsProtocol = true;
4662        break;
4663      }
4664    }
4665    // FIXME: For better diagnostics, consider passing back the protocol name.
4666    if (!RHSImplementsProtocol)
4667      return false;
4668  }
4669  // The RHS implements all protocols listed on the LHS.
4670  return true;
4671}
4672
4673bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
4674  // get the "pointed to" types
4675  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
4676  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
4677
4678  if (!LHSOPT || !RHSOPT)
4679    return false;
4680
4681  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
4682         canAssignObjCInterfaces(RHSOPT, LHSOPT);
4683}
4684
4685bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
4686  return canAssignObjCInterfaces(
4687                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
4688                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
4689}
4690
4691/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
4692/// both shall have the identically qualified version of a compatible type.
4693/// C99 6.2.7p1: Two types have compatible types if their types are the
4694/// same. See 6.7.[2,3,5] for additional rules.
4695bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
4696                                    bool CompareUnqualified) {
4697  if (getLangOptions().CPlusPlus)
4698    return hasSameType(LHS, RHS);
4699
4700  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
4701}
4702
4703bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
4704  return !mergeTypes(LHS, RHS, true).isNull();
4705}
4706
4707/// mergeTransparentUnionType - if T is a transparent union type and a member
4708/// of T is compatible with SubType, return the merged type, else return
4709/// QualType()
4710QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
4711                                               bool OfBlockPointer,
4712                                               bool Unqualified) {
4713  if (const RecordType *UT = T->getAsUnionType()) {
4714    RecordDecl *UD = UT->getDecl();
4715    if (UD->hasAttr<TransparentUnionAttr>()) {
4716      for (RecordDecl::field_iterator it = UD->field_begin(),
4717           itend = UD->field_end(); it != itend; ++it) {
4718        QualType ET = it->getType();
4719        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
4720        if (!MT.isNull())
4721          return MT;
4722      }
4723    }
4724  }
4725
4726  return QualType();
4727}
4728
4729/// mergeFunctionArgumentTypes - merge two types which appear as function
4730/// argument types
4731QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
4732                                                bool OfBlockPointer,
4733                                                bool Unqualified) {
4734  // GNU extension: two types are compatible if they appear as a function
4735  // argument, one of the types is a transparent union type and the other
4736  // type is compatible with a union member
4737  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
4738                                              Unqualified);
4739  if (!lmerge.isNull())
4740    return lmerge;
4741
4742  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
4743                                              Unqualified);
4744  if (!rmerge.isNull())
4745    return rmerge;
4746
4747  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
4748}
4749
4750QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
4751                                        bool OfBlockPointer,
4752                                        bool Unqualified) {
4753  const FunctionType *lbase = lhs->getAs<FunctionType>();
4754  const FunctionType *rbase = rhs->getAs<FunctionType>();
4755  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
4756  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
4757  bool allLTypes = true;
4758  bool allRTypes = true;
4759
4760  // Check return type
4761  QualType retType;
4762  if (OfBlockPointer)
4763    retType = mergeTypes(rbase->getResultType(), lbase->getResultType(), true,
4764                         Unqualified);
4765  else
4766   retType = mergeTypes(lbase->getResultType(), rbase->getResultType(),
4767                        false, Unqualified);
4768  if (retType.isNull()) return QualType();
4769
4770  if (Unqualified)
4771    retType = retType.getUnqualifiedType();
4772
4773  CanQualType LRetType = getCanonicalType(lbase->getResultType());
4774  CanQualType RRetType = getCanonicalType(rbase->getResultType());
4775  if (Unqualified) {
4776    LRetType = LRetType.getUnqualifiedType();
4777    RRetType = RRetType.getUnqualifiedType();
4778  }
4779
4780  if (getCanonicalType(retType) != LRetType)
4781    allLTypes = false;
4782  if (getCanonicalType(retType) != RRetType)
4783    allRTypes = false;
4784  // FIXME: double check this
4785  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
4786  //                           rbase->getRegParmAttr() != 0 &&
4787  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
4788  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
4789  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
4790  unsigned RegParm = lbaseInfo.getRegParm() == 0 ? rbaseInfo.getRegParm() :
4791      lbaseInfo.getRegParm();
4792  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
4793  if (NoReturn != lbaseInfo.getNoReturn() ||
4794      RegParm != lbaseInfo.getRegParm())
4795    allLTypes = false;
4796  if (NoReturn != rbaseInfo.getNoReturn() ||
4797      RegParm != rbaseInfo.getRegParm())
4798    allRTypes = false;
4799  CallingConv lcc = lbaseInfo.getCC();
4800  CallingConv rcc = rbaseInfo.getCC();
4801  // Compatible functions must have compatible calling conventions
4802  if (!isSameCallConv(lcc, rcc))
4803    return QualType();
4804
4805  if (lproto && rproto) { // two C99 style function prototypes
4806    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
4807           "C++ shouldn't be here");
4808    unsigned lproto_nargs = lproto->getNumArgs();
4809    unsigned rproto_nargs = rproto->getNumArgs();
4810
4811    // Compatible functions must have the same number of arguments
4812    if (lproto_nargs != rproto_nargs)
4813      return QualType();
4814
4815    // Variadic and non-variadic functions aren't compatible
4816    if (lproto->isVariadic() != rproto->isVariadic())
4817      return QualType();
4818
4819    if (lproto->getTypeQuals() != rproto->getTypeQuals())
4820      return QualType();
4821
4822    // Check argument compatibility
4823    llvm::SmallVector<QualType, 10> types;
4824    for (unsigned i = 0; i < lproto_nargs; i++) {
4825      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
4826      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
4827      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
4828                                                    OfBlockPointer,
4829                                                    Unqualified);
4830      if (argtype.isNull()) return QualType();
4831
4832      if (Unqualified)
4833        argtype = argtype.getUnqualifiedType();
4834
4835      types.push_back(argtype);
4836      if (Unqualified) {
4837        largtype = largtype.getUnqualifiedType();
4838        rargtype = rargtype.getUnqualifiedType();
4839      }
4840
4841      if (getCanonicalType(argtype) != getCanonicalType(largtype))
4842        allLTypes = false;
4843      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
4844        allRTypes = false;
4845    }
4846    if (allLTypes) return lhs;
4847    if (allRTypes) return rhs;
4848    return getFunctionType(retType, types.begin(), types.size(),
4849                           lproto->isVariadic(), lproto->getTypeQuals(),
4850                           false, false, 0, 0,
4851                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4852  }
4853
4854  if (lproto) allRTypes = false;
4855  if (rproto) allLTypes = false;
4856
4857  const FunctionProtoType *proto = lproto ? lproto : rproto;
4858  if (proto) {
4859    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
4860    if (proto->isVariadic()) return QualType();
4861    // Check that the types are compatible with the types that
4862    // would result from default argument promotions (C99 6.7.5.3p15).
4863    // The only types actually affected are promotable integer
4864    // types and floats, which would be passed as a different
4865    // type depending on whether the prototype is visible.
4866    unsigned proto_nargs = proto->getNumArgs();
4867    for (unsigned i = 0; i < proto_nargs; ++i) {
4868      QualType argTy = proto->getArgType(i);
4869
4870      // Look at the promotion type of enum types, since that is the type used
4871      // to pass enum values.
4872      if (const EnumType *Enum = argTy->getAs<EnumType>())
4873        argTy = Enum->getDecl()->getPromotionType();
4874
4875      if (argTy->isPromotableIntegerType() ||
4876          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
4877        return QualType();
4878    }
4879
4880    if (allLTypes) return lhs;
4881    if (allRTypes) return rhs;
4882    return getFunctionType(retType, proto->arg_type_begin(),
4883                           proto->getNumArgs(), proto->isVariadic(),
4884                           proto->getTypeQuals(),
4885                           false, false, 0, 0,
4886                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4887  }
4888
4889  if (allLTypes) return lhs;
4890  if (allRTypes) return rhs;
4891  FunctionType::ExtInfo Info(NoReturn, RegParm, lcc);
4892  return getFunctionNoProtoType(retType, Info);
4893}
4894
4895QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
4896                                bool OfBlockPointer,
4897                                bool Unqualified) {
4898  // C++ [expr]: If an expression initially has the type "reference to T", the
4899  // type is adjusted to "T" prior to any further analysis, the expression
4900  // designates the object or function denoted by the reference, and the
4901  // expression is an lvalue unless the reference is an rvalue reference and
4902  // the expression is a function call (possibly inside parentheses).
4903  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
4904  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
4905
4906  if (Unqualified) {
4907    LHS = LHS.getUnqualifiedType();
4908    RHS = RHS.getUnqualifiedType();
4909  }
4910
4911  QualType LHSCan = getCanonicalType(LHS),
4912           RHSCan = getCanonicalType(RHS);
4913
4914  // If two types are identical, they are compatible.
4915  if (LHSCan == RHSCan)
4916    return LHS;
4917
4918  // If the qualifiers are different, the types aren't compatible... mostly.
4919  Qualifiers LQuals = LHSCan.getLocalQualifiers();
4920  Qualifiers RQuals = RHSCan.getLocalQualifiers();
4921  if (LQuals != RQuals) {
4922    // If any of these qualifiers are different, we have a type
4923    // mismatch.
4924    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
4925        LQuals.getAddressSpace() != RQuals.getAddressSpace())
4926      return QualType();
4927
4928    // Exactly one GC qualifier difference is allowed: __strong is
4929    // okay if the other type has no GC qualifier but is an Objective
4930    // C object pointer (i.e. implicitly strong by default).  We fix
4931    // this by pretending that the unqualified type was actually
4932    // qualified __strong.
4933    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
4934    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
4935    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
4936
4937    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
4938      return QualType();
4939
4940    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
4941      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
4942    }
4943    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
4944      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
4945    }
4946    return QualType();
4947  }
4948
4949  // Okay, qualifiers are equal.
4950
4951  Type::TypeClass LHSClass = LHSCan->getTypeClass();
4952  Type::TypeClass RHSClass = RHSCan->getTypeClass();
4953
4954  // We want to consider the two function types to be the same for these
4955  // comparisons, just force one to the other.
4956  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
4957  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
4958
4959  // Same as above for arrays
4960  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
4961    LHSClass = Type::ConstantArray;
4962  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
4963    RHSClass = Type::ConstantArray;
4964
4965  // ObjCInterfaces are just specialized ObjCObjects.
4966  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
4967  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
4968
4969  // Canonicalize ExtVector -> Vector.
4970  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
4971  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
4972
4973  // If the canonical type classes don't match.
4974  if (LHSClass != RHSClass) {
4975    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
4976    // a signed integer type, or an unsigned integer type.
4977    // Compatibility is based on the underlying type, not the promotion
4978    // type.
4979    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
4980      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
4981        return RHS;
4982    }
4983    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
4984      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
4985        return LHS;
4986    }
4987
4988    return QualType();
4989  }
4990
4991  // The canonical type classes match.
4992  switch (LHSClass) {
4993#define TYPE(Class, Base)
4994#define ABSTRACT_TYPE(Class, Base)
4995#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
4996#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
4997#define DEPENDENT_TYPE(Class, Base) case Type::Class:
4998#include "clang/AST/TypeNodes.def"
4999    assert(false && "Non-canonical and dependent types shouldn't get here");
5000    return QualType();
5001
5002  case Type::LValueReference:
5003  case Type::RValueReference:
5004  case Type::MemberPointer:
5005    assert(false && "C++ should never be in mergeTypes");
5006    return QualType();
5007
5008  case Type::ObjCInterface:
5009  case Type::IncompleteArray:
5010  case Type::VariableArray:
5011  case Type::FunctionProto:
5012  case Type::ExtVector:
5013    assert(false && "Types are eliminated above");
5014    return QualType();
5015
5016  case Type::Pointer:
5017  {
5018    // Merge two pointer types, while trying to preserve typedef info
5019    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
5020    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
5021    if (Unqualified) {
5022      LHSPointee = LHSPointee.getUnqualifiedType();
5023      RHSPointee = RHSPointee.getUnqualifiedType();
5024    }
5025    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
5026                                     Unqualified);
5027    if (ResultType.isNull()) return QualType();
5028    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5029      return LHS;
5030    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5031      return RHS;
5032    return getPointerType(ResultType);
5033  }
5034  case Type::BlockPointer:
5035  {
5036    // Merge two block pointer types, while trying to preserve typedef info
5037    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
5038    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
5039    if (Unqualified) {
5040      LHSPointee = LHSPointee.getUnqualifiedType();
5041      RHSPointee = RHSPointee.getUnqualifiedType();
5042    }
5043    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
5044                                     Unqualified);
5045    if (ResultType.isNull()) return QualType();
5046    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5047      return LHS;
5048    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5049      return RHS;
5050    return getBlockPointerType(ResultType);
5051  }
5052  case Type::ConstantArray:
5053  {
5054    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
5055    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
5056    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
5057      return QualType();
5058
5059    QualType LHSElem = getAsArrayType(LHS)->getElementType();
5060    QualType RHSElem = getAsArrayType(RHS)->getElementType();
5061    if (Unqualified) {
5062      LHSElem = LHSElem.getUnqualifiedType();
5063      RHSElem = RHSElem.getUnqualifiedType();
5064    }
5065
5066    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
5067    if (ResultType.isNull()) return QualType();
5068    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5069      return LHS;
5070    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5071      return RHS;
5072    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
5073                                          ArrayType::ArraySizeModifier(), 0);
5074    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
5075                                          ArrayType::ArraySizeModifier(), 0);
5076    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
5077    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
5078    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5079      return LHS;
5080    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5081      return RHS;
5082    if (LVAT) {
5083      // FIXME: This isn't correct! But tricky to implement because
5084      // the array's size has to be the size of LHS, but the type
5085      // has to be different.
5086      return LHS;
5087    }
5088    if (RVAT) {
5089      // FIXME: This isn't correct! But tricky to implement because
5090      // the array's size has to be the size of RHS, but the type
5091      // has to be different.
5092      return RHS;
5093    }
5094    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
5095    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
5096    return getIncompleteArrayType(ResultType,
5097                                  ArrayType::ArraySizeModifier(), 0);
5098  }
5099  case Type::FunctionNoProto:
5100    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
5101  case Type::Record:
5102  case Type::Enum:
5103    return QualType();
5104  case Type::Builtin:
5105    // Only exactly equal builtin types are compatible, which is tested above.
5106    return QualType();
5107  case Type::Complex:
5108    // Distinct complex types are incompatible.
5109    return QualType();
5110  case Type::Vector:
5111    // FIXME: The merged type should be an ExtVector!
5112    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
5113                             RHSCan->getAs<VectorType>()))
5114      return LHS;
5115    return QualType();
5116  case Type::ObjCObject: {
5117    // Check if the types are assignment compatible.
5118    // FIXME: This should be type compatibility, e.g. whether
5119    // "LHS x; RHS x;" at global scope is legal.
5120    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
5121    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
5122    if (canAssignObjCInterfaces(LHSIface, RHSIface))
5123      return LHS;
5124
5125    return QualType();
5126  }
5127  case Type::ObjCObjectPointer: {
5128    if (OfBlockPointer) {
5129      if (canAssignObjCInterfacesInBlockPointer(
5130                                          LHS->getAs<ObjCObjectPointerType>(),
5131                                          RHS->getAs<ObjCObjectPointerType>()))
5132      return LHS;
5133      return QualType();
5134    }
5135    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
5136                                RHS->getAs<ObjCObjectPointerType>()))
5137      return LHS;
5138
5139    return QualType();
5140    }
5141  }
5142
5143  return QualType();
5144}
5145
5146/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
5147/// 'RHS' attributes and returns the merged version; including for function
5148/// return types.
5149QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
5150  QualType LHSCan = getCanonicalType(LHS),
5151  RHSCan = getCanonicalType(RHS);
5152  // If two types are identical, they are compatible.
5153  if (LHSCan == RHSCan)
5154    return LHS;
5155  if (RHSCan->isFunctionType()) {
5156    if (!LHSCan->isFunctionType())
5157      return QualType();
5158    QualType OldReturnType =
5159      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
5160    QualType NewReturnType =
5161      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
5162    QualType ResReturnType =
5163      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
5164    if (ResReturnType.isNull())
5165      return QualType();
5166    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
5167      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
5168      // In either case, use OldReturnType to build the new function type.
5169      const FunctionType *F = LHS->getAs<FunctionType>();
5170      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
5171        FunctionType::ExtInfo Info = getFunctionExtInfo(LHS);
5172        QualType ResultType
5173          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
5174                                  FPT->getNumArgs(), FPT->isVariadic(),
5175                                  FPT->getTypeQuals(),
5176                                  FPT->hasExceptionSpec(),
5177                                  FPT->hasAnyExceptionSpec(),
5178                                  FPT->getNumExceptions(),
5179                                  FPT->exception_begin(),
5180                                  Info);
5181        return ResultType;
5182      }
5183    }
5184    return QualType();
5185  }
5186
5187  // If the qualifiers are different, the types can still be merged.
5188  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5189  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5190  if (LQuals != RQuals) {
5191    // If any of these qualifiers are different, we have a type mismatch.
5192    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5193        LQuals.getAddressSpace() != RQuals.getAddressSpace())
5194      return QualType();
5195
5196    // Exactly one GC qualifier difference is allowed: __strong is
5197    // okay if the other type has no GC qualifier but is an Objective
5198    // C object pointer (i.e. implicitly strong by default).  We fix
5199    // this by pretending that the unqualified type was actually
5200    // qualified __strong.
5201    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5202    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5203    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5204
5205    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5206      return QualType();
5207
5208    if (GC_L == Qualifiers::Strong)
5209      return LHS;
5210    if (GC_R == Qualifiers::Strong)
5211      return RHS;
5212    return QualType();
5213  }
5214
5215  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
5216    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5217    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5218    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
5219    if (ResQT == LHSBaseQT)
5220      return LHS;
5221    if (ResQT == RHSBaseQT)
5222      return RHS;
5223  }
5224  return QualType();
5225}
5226
5227//===----------------------------------------------------------------------===//
5228//                         Integer Predicates
5229//===----------------------------------------------------------------------===//
5230
5231unsigned ASTContext::getIntWidth(QualType T) {
5232  if (EnumType *ET = dyn_cast<EnumType>(T))
5233    T = ET->getDecl()->getIntegerType();
5234  if (T->isBooleanType())
5235    return 1;
5236  // For builtin types, just use the standard type sizing method
5237  return (unsigned)getTypeSize(T);
5238}
5239
5240QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
5241  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
5242
5243  // Turn <4 x signed int> -> <4 x unsigned int>
5244  if (const VectorType *VTy = T->getAs<VectorType>())
5245    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
5246             VTy->getNumElements(), VTy->getAltiVecSpecific());
5247
5248  // For enums, we return the unsigned version of the base type.
5249  if (const EnumType *ETy = T->getAs<EnumType>())
5250    T = ETy->getDecl()->getIntegerType();
5251
5252  const BuiltinType *BTy = T->getAs<BuiltinType>();
5253  assert(BTy && "Unexpected signed integer type");
5254  switch (BTy->getKind()) {
5255  case BuiltinType::Char_S:
5256  case BuiltinType::SChar:
5257    return UnsignedCharTy;
5258  case BuiltinType::Short:
5259    return UnsignedShortTy;
5260  case BuiltinType::Int:
5261    return UnsignedIntTy;
5262  case BuiltinType::Long:
5263    return UnsignedLongTy;
5264  case BuiltinType::LongLong:
5265    return UnsignedLongLongTy;
5266  case BuiltinType::Int128:
5267    return UnsignedInt128Ty;
5268  default:
5269    assert(0 && "Unexpected signed integer type");
5270    return QualType();
5271  }
5272}
5273
5274ExternalASTSource::~ExternalASTSource() { }
5275
5276void ExternalASTSource::PrintStats() { }
5277
5278ASTMutationListener::~ASTMutationListener() { }
5279
5280
5281//===----------------------------------------------------------------------===//
5282//                          Builtin Type Computation
5283//===----------------------------------------------------------------------===//
5284
5285/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
5286/// pointer over the consumed characters.  This returns the resultant type.  If
5287/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
5288/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
5289/// a vector of "i*".
5290///
5291/// RequiresICE is filled in on return to indicate whether the value is required
5292/// to be an Integer Constant Expression.
5293static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
5294                                  ASTContext::GetBuiltinTypeError &Error,
5295                                  bool &RequiresICE,
5296                                  bool AllowTypeModifiers) {
5297  // Modifiers.
5298  int HowLong = 0;
5299  bool Signed = false, Unsigned = false;
5300  RequiresICE = false;
5301
5302  // Read the prefixed modifiers first.
5303  bool Done = false;
5304  while (!Done) {
5305    switch (*Str++) {
5306    default: Done = true; --Str; break;
5307    case 'I':
5308      RequiresICE = true;
5309      break;
5310    case 'S':
5311      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
5312      assert(!Signed && "Can't use 'S' modifier multiple times!");
5313      Signed = true;
5314      break;
5315    case 'U':
5316      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
5317      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
5318      Unsigned = true;
5319      break;
5320    case 'L':
5321      assert(HowLong <= 2 && "Can't have LLLL modifier");
5322      ++HowLong;
5323      break;
5324    }
5325  }
5326
5327  QualType Type;
5328
5329  // Read the base type.
5330  switch (*Str++) {
5331  default: assert(0 && "Unknown builtin type letter!");
5332  case 'v':
5333    assert(HowLong == 0 && !Signed && !Unsigned &&
5334           "Bad modifiers used with 'v'!");
5335    Type = Context.VoidTy;
5336    break;
5337  case 'f':
5338    assert(HowLong == 0 && !Signed && !Unsigned &&
5339           "Bad modifiers used with 'f'!");
5340    Type = Context.FloatTy;
5341    break;
5342  case 'd':
5343    assert(HowLong < 2 && !Signed && !Unsigned &&
5344           "Bad modifiers used with 'd'!");
5345    if (HowLong)
5346      Type = Context.LongDoubleTy;
5347    else
5348      Type = Context.DoubleTy;
5349    break;
5350  case 's':
5351    assert(HowLong == 0 && "Bad modifiers used with 's'!");
5352    if (Unsigned)
5353      Type = Context.UnsignedShortTy;
5354    else
5355      Type = Context.ShortTy;
5356    break;
5357  case 'i':
5358    if (HowLong == 3)
5359      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
5360    else if (HowLong == 2)
5361      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
5362    else if (HowLong == 1)
5363      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
5364    else
5365      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
5366    break;
5367  case 'c':
5368    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
5369    if (Signed)
5370      Type = Context.SignedCharTy;
5371    else if (Unsigned)
5372      Type = Context.UnsignedCharTy;
5373    else
5374      Type = Context.CharTy;
5375    break;
5376  case 'b': // boolean
5377    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
5378    Type = Context.BoolTy;
5379    break;
5380  case 'z':  // size_t.
5381    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
5382    Type = Context.getSizeType();
5383    break;
5384  case 'F':
5385    Type = Context.getCFConstantStringType();
5386    break;
5387  case 'G':
5388    Type = Context.getObjCIdType();
5389    break;
5390  case 'H':
5391    Type = Context.getObjCSelType();
5392    break;
5393  case 'a':
5394    Type = Context.getBuiltinVaListType();
5395    assert(!Type.isNull() && "builtin va list type not initialized!");
5396    break;
5397  case 'A':
5398    // This is a "reference" to a va_list; however, what exactly
5399    // this means depends on how va_list is defined. There are two
5400    // different kinds of va_list: ones passed by value, and ones
5401    // passed by reference.  An example of a by-value va_list is
5402    // x86, where va_list is a char*. An example of by-ref va_list
5403    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
5404    // we want this argument to be a char*&; for x86-64, we want
5405    // it to be a __va_list_tag*.
5406    Type = Context.getBuiltinVaListType();
5407    assert(!Type.isNull() && "builtin va list type not initialized!");
5408    if (Type->isArrayType())
5409      Type = Context.getArrayDecayedType(Type);
5410    else
5411      Type = Context.getLValueReferenceType(Type);
5412    break;
5413  case 'V': {
5414    char *End;
5415    unsigned NumElements = strtoul(Str, &End, 10);
5416    assert(End != Str && "Missing vector size");
5417    Str = End;
5418
5419    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
5420                                             RequiresICE, false);
5421    assert(!RequiresICE && "Can't require vector ICE");
5422
5423    // TODO: No way to make AltiVec vectors in builtins yet.
5424    Type = Context.getVectorType(ElementType, NumElements,
5425                                 VectorType::NotAltiVec);
5426    break;
5427  }
5428  case 'X': {
5429    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
5430                                             false);
5431    assert(!RequiresICE && "Can't require complex ICE");
5432    Type = Context.getComplexType(ElementType);
5433    break;
5434  }
5435  case 'P':
5436    Type = Context.getFILEType();
5437    if (Type.isNull()) {
5438      Error = ASTContext::GE_Missing_stdio;
5439      return QualType();
5440    }
5441    break;
5442  case 'J':
5443    if (Signed)
5444      Type = Context.getsigjmp_bufType();
5445    else
5446      Type = Context.getjmp_bufType();
5447
5448    if (Type.isNull()) {
5449      Error = ASTContext::GE_Missing_setjmp;
5450      return QualType();
5451    }
5452    break;
5453  }
5454
5455  // If there are modifiers and if we're allowed to parse them, go for it.
5456  Done = !AllowTypeModifiers;
5457  while (!Done) {
5458    switch (char c = *Str++) {
5459    default: Done = true; --Str; break;
5460    case '*':
5461    case '&': {
5462      // Both pointers and references can have their pointee types
5463      // qualified with an address space.
5464      char *End;
5465      unsigned AddrSpace = strtoul(Str, &End, 10);
5466      if (End != Str && AddrSpace != 0) {
5467        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
5468        Str = End;
5469      }
5470      if (c == '*')
5471        Type = Context.getPointerType(Type);
5472      else
5473        Type = Context.getLValueReferenceType(Type);
5474      break;
5475    }
5476    // FIXME: There's no way to have a built-in with an rvalue ref arg.
5477    case 'C':
5478      Type = Type.withConst();
5479      break;
5480    case 'D':
5481      Type = Context.getVolatileType(Type);
5482      break;
5483    }
5484  }
5485
5486  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
5487         "Integer constant 'I' type must be an integer");
5488
5489  return Type;
5490}
5491
5492/// GetBuiltinType - Return the type for the specified builtin.
5493QualType ASTContext::GetBuiltinType(unsigned Id,
5494                                    GetBuiltinTypeError &Error,
5495                                    unsigned *IntegerConstantArgs) {
5496  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
5497
5498  llvm::SmallVector<QualType, 8> ArgTypes;
5499
5500  bool RequiresICE = false;
5501  Error = GE_None;
5502  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
5503                                       RequiresICE, true);
5504  if (Error != GE_None)
5505    return QualType();
5506
5507  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
5508
5509  while (TypeStr[0] && TypeStr[0] != '.') {
5510    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
5511    if (Error != GE_None)
5512      return QualType();
5513
5514    // If this argument is required to be an IntegerConstantExpression and the
5515    // caller cares, fill in the bitmask we return.
5516    if (RequiresICE && IntegerConstantArgs)
5517      *IntegerConstantArgs |= 1 << ArgTypes.size();
5518
5519    // Do array -> pointer decay.  The builtin should use the decayed type.
5520    if (Ty->isArrayType())
5521      Ty = getArrayDecayedType(Ty);
5522
5523    ArgTypes.push_back(Ty);
5524  }
5525
5526  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
5527         "'.' should only occur at end of builtin type list!");
5528
5529  // handle untyped/variadic arguments "T c99Style();" or "T cppStyle(...);".
5530  if (ArgTypes.size() == 0 && TypeStr[0] == '.')
5531    return getFunctionNoProtoType(ResType);
5532
5533  // FIXME: Should we create noreturn types?
5534  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(),
5535                         TypeStr[0] == '.', 0, false, false, 0, 0,
5536                         FunctionType::ExtInfo());
5537}
5538
5539QualType
5540ASTContext::UsualArithmeticConversionsType(QualType lhs, QualType rhs) {
5541  // Perform the usual unary conversions. We do this early so that
5542  // integral promotions to "int" can allow us to exit early, in the
5543  // lhs == rhs check. Also, for conversion purposes, we ignore any
5544  // qualifiers.  For example, "const float" and "float" are
5545  // equivalent.
5546  if (lhs->isPromotableIntegerType())
5547    lhs = getPromotedIntegerType(lhs);
5548  else
5549    lhs = lhs.getUnqualifiedType();
5550  if (rhs->isPromotableIntegerType())
5551    rhs = getPromotedIntegerType(rhs);
5552  else
5553    rhs = rhs.getUnqualifiedType();
5554
5555  // If both types are identical, no conversion is needed.
5556  if (lhs == rhs)
5557    return lhs;
5558
5559  // If either side is a non-arithmetic type (e.g. a pointer), we are done.
5560  // The caller can deal with this (e.g. pointer + int).
5561  if (!lhs->isArithmeticType() || !rhs->isArithmeticType())
5562    return lhs;
5563
5564  // At this point, we have two different arithmetic types.
5565
5566  // Handle complex types first (C99 6.3.1.8p1).
5567  if (lhs->isComplexType() || rhs->isComplexType()) {
5568    // if we have an integer operand, the result is the complex type.
5569    if (rhs->isIntegerType() || rhs->isComplexIntegerType()) {
5570      // convert the rhs to the lhs complex type.
5571      return lhs;
5572    }
5573    if (lhs->isIntegerType() || lhs->isComplexIntegerType()) {
5574      // convert the lhs to the rhs complex type.
5575      return rhs;
5576    }
5577    // This handles complex/complex, complex/float, or float/complex.
5578    // When both operands are complex, the shorter operand is converted to the
5579    // type of the longer, and that is the type of the result. This corresponds
5580    // to what is done when combining two real floating-point operands.
5581    // The fun begins when size promotion occur across type domains.
5582    // From H&S 6.3.4: When one operand is complex and the other is a real
5583    // floating-point type, the less precise type is converted, within it's
5584    // real or complex domain, to the precision of the other type. For example,
5585    // when combining a "long double" with a "double _Complex", the
5586    // "double _Complex" is promoted to "long double _Complex".
5587    int result = getFloatingTypeOrder(lhs, rhs);
5588
5589    if (result > 0) { // The left side is bigger, convert rhs.
5590      rhs = getFloatingTypeOfSizeWithinDomain(lhs, rhs);
5591    } else if (result < 0) { // The right side is bigger, convert lhs.
5592      lhs = getFloatingTypeOfSizeWithinDomain(rhs, lhs);
5593    }
5594    // At this point, lhs and rhs have the same rank/size. Now, make sure the
5595    // domains match. This is a requirement for our implementation, C99
5596    // does not require this promotion.
5597    if (lhs != rhs) { // Domains don't match, we have complex/float mix.
5598      if (lhs->isRealFloatingType()) { // handle "double, _Complex double".
5599        return rhs;
5600      } else { // handle "_Complex double, double".
5601        return lhs;
5602      }
5603    }
5604    return lhs; // The domain/size match exactly.
5605  }
5606  // Now handle "real" floating types (i.e. float, double, long double).
5607  if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) {
5608    // if we have an integer operand, the result is the real floating type.
5609    if (rhs->isIntegerType()) {
5610      // convert rhs to the lhs floating point type.
5611      return lhs;
5612    }
5613    if (rhs->isComplexIntegerType()) {
5614      // convert rhs to the complex floating point type.
5615      return getComplexType(lhs);
5616    }
5617    if (lhs->isIntegerType()) {
5618      // convert lhs to the rhs floating point type.
5619      return rhs;
5620    }
5621    if (lhs->isComplexIntegerType()) {
5622      // convert lhs to the complex floating point type.
5623      return getComplexType(rhs);
5624    }
5625    // We have two real floating types, float/complex combos were handled above.
5626    // Convert the smaller operand to the bigger result.
5627    int result = getFloatingTypeOrder(lhs, rhs);
5628    if (result > 0) // convert the rhs
5629      return lhs;
5630    assert(result < 0 && "illegal float comparison");
5631    return rhs;   // convert the lhs
5632  }
5633  if (lhs->isComplexIntegerType() || rhs->isComplexIntegerType()) {
5634    // Handle GCC complex int extension.
5635    const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType();
5636    const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType();
5637
5638    if (lhsComplexInt && rhsComplexInt) {
5639      if (getIntegerTypeOrder(lhsComplexInt->getElementType(),
5640                              rhsComplexInt->getElementType()) >= 0)
5641        return lhs; // convert the rhs
5642      return rhs;
5643    } else if (lhsComplexInt && rhs->isIntegerType()) {
5644      // convert the rhs to the lhs complex type.
5645      return lhs;
5646    } else if (rhsComplexInt && lhs->isIntegerType()) {
5647      // convert the lhs to the rhs complex type.
5648      return rhs;
5649    }
5650  }
5651  // Finally, we have two differing integer types.
5652  // The rules for this case are in C99 6.3.1.8
5653  int compare = getIntegerTypeOrder(lhs, rhs);
5654  bool lhsSigned = lhs->hasSignedIntegerRepresentation(),
5655       rhsSigned = rhs->hasSignedIntegerRepresentation();
5656  QualType destType;
5657  if (lhsSigned == rhsSigned) {
5658    // Same signedness; use the higher-ranked type
5659    destType = compare >= 0 ? lhs : rhs;
5660  } else if (compare != (lhsSigned ? 1 : -1)) {
5661    // The unsigned type has greater than or equal rank to the
5662    // signed type, so use the unsigned type
5663    destType = lhsSigned ? rhs : lhs;
5664  } else if (getIntWidth(lhs) != getIntWidth(rhs)) {
5665    // The two types are different widths; if we are here, that
5666    // means the signed type is larger than the unsigned type, so
5667    // use the signed type.
5668    destType = lhsSigned ? lhs : rhs;
5669  } else {
5670    // The signed type is higher-ranked than the unsigned type,
5671    // but isn't actually any bigger (like unsigned int and long
5672    // on most 32-bit systems).  Use the unsigned type corresponding
5673    // to the signed type.
5674    destType = getCorrespondingUnsignedType(lhsSigned ? lhs : rhs);
5675  }
5676  return destType;
5677}
5678
5679GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
5680  GVALinkage External = GVA_StrongExternal;
5681
5682  Linkage L = FD->getLinkage();
5683  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5684      FD->getType()->getLinkage() == UniqueExternalLinkage)
5685    L = UniqueExternalLinkage;
5686
5687  switch (L) {
5688  case NoLinkage:
5689  case InternalLinkage:
5690  case UniqueExternalLinkage:
5691    return GVA_Internal;
5692
5693  case ExternalLinkage:
5694    switch (FD->getTemplateSpecializationKind()) {
5695    case TSK_Undeclared:
5696    case TSK_ExplicitSpecialization:
5697      External = GVA_StrongExternal;
5698      break;
5699
5700    case TSK_ExplicitInstantiationDefinition:
5701      return GVA_ExplicitTemplateInstantiation;
5702
5703    case TSK_ExplicitInstantiationDeclaration:
5704    case TSK_ImplicitInstantiation:
5705      External = GVA_TemplateInstantiation;
5706      break;
5707    }
5708  }
5709
5710  if (!FD->isInlined())
5711    return External;
5712
5713  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
5714    // GNU or C99 inline semantics. Determine whether this symbol should be
5715    // externally visible.
5716    if (FD->isInlineDefinitionExternallyVisible())
5717      return External;
5718
5719    // C99 inline semantics, where the symbol is not externally visible.
5720    return GVA_C99Inline;
5721  }
5722
5723  // C++0x [temp.explicit]p9:
5724  //   [ Note: The intent is that an inline function that is the subject of
5725  //   an explicit instantiation declaration will still be implicitly
5726  //   instantiated when used so that the body can be considered for
5727  //   inlining, but that no out-of-line copy of the inline function would be
5728  //   generated in the translation unit. -- end note ]
5729  if (FD->getTemplateSpecializationKind()
5730                                       == TSK_ExplicitInstantiationDeclaration)
5731    return GVA_C99Inline;
5732
5733  return GVA_CXXInline;
5734}
5735
5736GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
5737  // If this is a static data member, compute the kind of template
5738  // specialization. Otherwise, this variable is not part of a
5739  // template.
5740  TemplateSpecializationKind TSK = TSK_Undeclared;
5741  if (VD->isStaticDataMember())
5742    TSK = VD->getTemplateSpecializationKind();
5743
5744  Linkage L = VD->getLinkage();
5745  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5746      VD->getType()->getLinkage() == UniqueExternalLinkage)
5747    L = UniqueExternalLinkage;
5748
5749  switch (L) {
5750  case NoLinkage:
5751  case InternalLinkage:
5752  case UniqueExternalLinkage:
5753    return GVA_Internal;
5754
5755  case ExternalLinkage:
5756    switch (TSK) {
5757    case TSK_Undeclared:
5758    case TSK_ExplicitSpecialization:
5759      return GVA_StrongExternal;
5760
5761    case TSK_ExplicitInstantiationDeclaration:
5762      llvm_unreachable("Variable should not be instantiated");
5763      // Fall through to treat this like any other instantiation.
5764
5765    case TSK_ExplicitInstantiationDefinition:
5766      return GVA_ExplicitTemplateInstantiation;
5767
5768    case TSK_ImplicitInstantiation:
5769      return GVA_TemplateInstantiation;
5770    }
5771  }
5772
5773  return GVA_StrongExternal;
5774}
5775
5776bool ASTContext::DeclMustBeEmitted(const Decl *D) {
5777  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
5778    if (!VD->isFileVarDecl())
5779      return false;
5780  } else if (!isa<FunctionDecl>(D))
5781    return false;
5782
5783  // Weak references don't produce any output by themselves.
5784  if (D->hasAttr<WeakRefAttr>())
5785    return false;
5786
5787  // Aliases and used decls are required.
5788  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
5789    return true;
5790
5791  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
5792    // Forward declarations aren't required.
5793    if (!FD->isThisDeclarationADefinition())
5794      return false;
5795
5796    // Constructors and destructors are required.
5797    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
5798      return true;
5799
5800    // The key function for a class is required.
5801    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
5802      const CXXRecordDecl *RD = MD->getParent();
5803      if (MD->isOutOfLine() && RD->isDynamicClass()) {
5804        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
5805        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
5806          return true;
5807      }
5808    }
5809
5810    GVALinkage Linkage = GetGVALinkageForFunction(FD);
5811
5812    // static, static inline, always_inline, and extern inline functions can
5813    // always be deferred.  Normal inline functions can be deferred in C99/C++.
5814    // Implicit template instantiations can also be deferred in C++.
5815    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
5816        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
5817      return false;
5818    return true;
5819  }
5820
5821  const VarDecl *VD = cast<VarDecl>(D);
5822  assert(VD->isFileVarDecl() && "Expected file scoped var");
5823
5824  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
5825    return false;
5826
5827  // Structs that have non-trivial constructors or destructors are required.
5828
5829  // FIXME: Handle references.
5830  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
5831    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
5832      if (RD->hasDefinition() &&
5833          (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()))
5834        return true;
5835    }
5836  }
5837
5838  GVALinkage L = GetGVALinkageForVariable(VD);
5839  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
5840    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
5841      return false;
5842  }
5843
5844  return true;
5845}
5846
5847CXXABI::~CXXABI() {}
5848