ASTContext.cpp revision 9a44b5f5593bd8a385d06b07c564795f643ec8da 
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      // FIXME: Allocate in ASTContext
2688      TemplateArgument *CanonArgs = new 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      TemplateArgument Result;
2696      Result.setArgumentPack(CanonArgs, Arg.pack_size(), false);
2697      return Result;
2698    }
2699  }
2700
2701  // Silence GCC warning
2702  assert(false && "Unhandled template argument kind");
2703  return TemplateArgument();
2704}
2705
2706NestedNameSpecifier *
2707ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) {
2708  if (!NNS)
2709    return 0;
2710
2711  switch (NNS->getKind()) {
2712  case NestedNameSpecifier::Identifier:
2713    // Canonicalize the prefix but keep the identifier the same.
2714    return NestedNameSpecifier::Create(*this,
2715                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
2716                                       NNS->getAsIdentifier());
2717
2718  case NestedNameSpecifier::Namespace:
2719    // A namespace is canonical; build a nested-name-specifier with
2720    // this namespace and no prefix.
2721    return NestedNameSpecifier::Create(*this, 0, NNS->getAsNamespace());
2722
2723  case NestedNameSpecifier::TypeSpec:
2724  case NestedNameSpecifier::TypeSpecWithTemplate: {
2725    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
2726    return NestedNameSpecifier::Create(*this, 0,
2727                 NNS->getKind() == NestedNameSpecifier::TypeSpecWithTemplate,
2728                                       T.getTypePtr());
2729  }
2730
2731  case NestedNameSpecifier::Global:
2732    // The global specifier is canonical and unique.
2733    return NNS;
2734  }
2735
2736  // Required to silence a GCC warning
2737  return 0;
2738}
2739
2740
2741const ArrayType *ASTContext::getAsArrayType(QualType T) {
2742  // Handle the non-qualified case efficiently.
2743  if (!T.hasLocalQualifiers()) {
2744    // Handle the common positive case fast.
2745    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
2746      return AT;
2747  }
2748
2749  // Handle the common negative case fast.
2750  QualType CType = T->getCanonicalTypeInternal();
2751  if (!isa<ArrayType>(CType))
2752    return 0;
2753
2754  // Apply any qualifiers from the array type to the element type.  This
2755  // implements C99 6.7.3p8: "If the specification of an array type includes
2756  // any type qualifiers, the element type is so qualified, not the array type."
2757
2758  // If we get here, we either have type qualifiers on the type, or we have
2759  // sugar such as a typedef in the way.  If we have type qualifiers on the type
2760  // we must propagate them down into the element type.
2761
2762  QualifierCollector Qs;
2763  const Type *Ty = Qs.strip(T.getDesugaredType());
2764
2765  // If we have a simple case, just return now.
2766  const ArrayType *ATy = dyn_cast<ArrayType>(Ty);
2767  if (ATy == 0 || Qs.empty())
2768    return ATy;
2769
2770  // Otherwise, we have an array and we have qualifiers on it.  Push the
2771  // qualifiers into the array element type and return a new array type.
2772  // Get the canonical version of the element with the extra qualifiers on it.
2773  // This can recursively sink qualifiers through multiple levels of arrays.
2774  QualType NewEltTy = getQualifiedType(ATy->getElementType(), Qs);
2775
2776  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
2777    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
2778                                                CAT->getSizeModifier(),
2779                                           CAT->getIndexTypeCVRQualifiers()));
2780  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
2781    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
2782                                                  IAT->getSizeModifier(),
2783                                           IAT->getIndexTypeCVRQualifiers()));
2784
2785  if (const DependentSizedArrayType *DSAT
2786        = dyn_cast<DependentSizedArrayType>(ATy))
2787    return cast<ArrayType>(
2788                     getDependentSizedArrayType(NewEltTy,
2789                                                DSAT->getSizeExpr(),
2790                                                DSAT->getSizeModifier(),
2791                                              DSAT->getIndexTypeCVRQualifiers(),
2792                                                DSAT->getBracketsRange()));
2793
2794  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
2795  return cast<ArrayType>(getVariableArrayType(NewEltTy,
2796                                              VAT->getSizeExpr(),
2797                                              VAT->getSizeModifier(),
2798                                              VAT->getIndexTypeCVRQualifiers(),
2799                                              VAT->getBracketsRange()));
2800}
2801
2802/// getArrayDecayedType - Return the properly qualified result of decaying the
2803/// specified array type to a pointer.  This operation is non-trivial when
2804/// handling typedefs etc.  The canonical type of "T" must be an array type,
2805/// this returns a pointer to a properly qualified element of the array.
2806///
2807/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
2808QualType ASTContext::getArrayDecayedType(QualType Ty) {
2809  // Get the element type with 'getAsArrayType' so that we don't lose any
2810  // typedefs in the element type of the array.  This also handles propagation
2811  // of type qualifiers from the array type into the element type if present
2812  // (C99 6.7.3p8).
2813  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
2814  assert(PrettyArrayType && "Not an array type!");
2815
2816  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
2817
2818  // int x[restrict 4] ->  int *restrict
2819  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
2820}
2821
2822QualType ASTContext::getBaseElementType(QualType QT) {
2823  QualifierCollector Qs;
2824  while (const ArrayType *AT = getAsArrayType(QualType(Qs.strip(QT), 0)))
2825    QT = AT->getElementType();
2826  return Qs.apply(QT);
2827}
2828
2829QualType ASTContext::getBaseElementType(const ArrayType *AT) {
2830  QualType ElemTy = AT->getElementType();
2831
2832  if (const ArrayType *AT = getAsArrayType(ElemTy))
2833    return getBaseElementType(AT);
2834
2835  return ElemTy;
2836}
2837
2838/// getConstantArrayElementCount - Returns number of constant array elements.
2839uint64_t
2840ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
2841  uint64_t ElementCount = 1;
2842  do {
2843    ElementCount *= CA->getSize().getZExtValue();
2844    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
2845  } while (CA);
2846  return ElementCount;
2847}
2848
2849/// getFloatingRank - Return a relative rank for floating point types.
2850/// This routine will assert if passed a built-in type that isn't a float.
2851static FloatingRank getFloatingRank(QualType T) {
2852  if (const ComplexType *CT = T->getAs<ComplexType>())
2853    return getFloatingRank(CT->getElementType());
2854
2855  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
2856  switch (T->getAs<BuiltinType>()->getKind()) {
2857  default: assert(0 && "getFloatingRank(): not a floating type");
2858  case BuiltinType::Float:      return FloatRank;
2859  case BuiltinType::Double:     return DoubleRank;
2860  case BuiltinType::LongDouble: return LongDoubleRank;
2861  }
2862}
2863
2864/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
2865/// point or a complex type (based on typeDomain/typeSize).
2866/// 'typeDomain' is a real floating point or complex type.
2867/// 'typeSize' is a real floating point or complex type.
2868QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
2869                                                       QualType Domain) const {
2870  FloatingRank EltRank = getFloatingRank(Size);
2871  if (Domain->isComplexType()) {
2872    switch (EltRank) {
2873    default: assert(0 && "getFloatingRank(): illegal value for rank");
2874    case FloatRank:      return FloatComplexTy;
2875    case DoubleRank:     return DoubleComplexTy;
2876    case LongDoubleRank: return LongDoubleComplexTy;
2877    }
2878  }
2879
2880  assert(Domain->isRealFloatingType() && "Unknown domain!");
2881  switch (EltRank) {
2882  default: assert(0 && "getFloatingRank(): illegal value for rank");
2883  case FloatRank:      return FloatTy;
2884  case DoubleRank:     return DoubleTy;
2885  case LongDoubleRank: return LongDoubleTy;
2886  }
2887}
2888
2889/// getFloatingTypeOrder - Compare the rank of the two specified floating
2890/// point types, ignoring the domain of the type (i.e. 'double' ==
2891/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2892/// LHS < RHS, return -1.
2893int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) {
2894  FloatingRank LHSR = getFloatingRank(LHS);
2895  FloatingRank RHSR = getFloatingRank(RHS);
2896
2897  if (LHSR == RHSR)
2898    return 0;
2899  if (LHSR > RHSR)
2900    return 1;
2901  return -1;
2902}
2903
2904/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
2905/// routine will assert if passed a built-in type that isn't an integer or enum,
2906/// or if it is not canonicalized.
2907unsigned ASTContext::getIntegerRank(Type *T) {
2908  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
2909  if (EnumType* ET = dyn_cast<EnumType>(T))
2910    T = ET->getDecl()->getPromotionType().getTypePtr();
2911
2912  if (T->isSpecificBuiltinType(BuiltinType::WChar))
2913    T = getFromTargetType(Target.getWCharType()).getTypePtr();
2914
2915  if (T->isSpecificBuiltinType(BuiltinType::Char16))
2916    T = getFromTargetType(Target.getChar16Type()).getTypePtr();
2917
2918  if (T->isSpecificBuiltinType(BuiltinType::Char32))
2919    T = getFromTargetType(Target.getChar32Type()).getTypePtr();
2920
2921  switch (cast<BuiltinType>(T)->getKind()) {
2922  default: assert(0 && "getIntegerRank(): not a built-in integer");
2923  case BuiltinType::Bool:
2924    return 1 + (getIntWidth(BoolTy) << 3);
2925  case BuiltinType::Char_S:
2926  case BuiltinType::Char_U:
2927  case BuiltinType::SChar:
2928  case BuiltinType::UChar:
2929    return 2 + (getIntWidth(CharTy) << 3);
2930  case BuiltinType::Short:
2931  case BuiltinType::UShort:
2932    return 3 + (getIntWidth(ShortTy) << 3);
2933  case BuiltinType::Int:
2934  case BuiltinType::UInt:
2935    return 4 + (getIntWidth(IntTy) << 3);
2936  case BuiltinType::Long:
2937  case BuiltinType::ULong:
2938    return 5 + (getIntWidth(LongTy) << 3);
2939  case BuiltinType::LongLong:
2940  case BuiltinType::ULongLong:
2941    return 6 + (getIntWidth(LongLongTy) << 3);
2942  case BuiltinType::Int128:
2943  case BuiltinType::UInt128:
2944    return 7 + (getIntWidth(Int128Ty) << 3);
2945  }
2946}
2947
2948/// \brief Whether this is a promotable bitfield reference according
2949/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
2950///
2951/// \returns the type this bit-field will promote to, or NULL if no
2952/// promotion occurs.
2953QualType ASTContext::isPromotableBitField(Expr *E) {
2954  if (E->isTypeDependent() || E->isValueDependent())
2955    return QualType();
2956
2957  FieldDecl *Field = E->getBitField();
2958  if (!Field)
2959    return QualType();
2960
2961  QualType FT = Field->getType();
2962
2963  llvm::APSInt BitWidthAP = Field->getBitWidth()->EvaluateAsInt(*this);
2964  uint64_t BitWidth = BitWidthAP.getZExtValue();
2965  uint64_t IntSize = getTypeSize(IntTy);
2966  // GCC extension compatibility: if the bit-field size is less than or equal
2967  // to the size of int, it gets promoted no matter what its type is.
2968  // For instance, unsigned long bf : 4 gets promoted to signed int.
2969  if (BitWidth < IntSize)
2970    return IntTy;
2971
2972  if (BitWidth == IntSize)
2973    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
2974
2975  // Types bigger than int are not subject to promotions, and therefore act
2976  // like the base type.
2977  // FIXME: This doesn't quite match what gcc does, but what gcc does here
2978  // is ridiculous.
2979  return QualType();
2980}
2981
2982/// getPromotedIntegerType - Returns the type that Promotable will
2983/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
2984/// integer type.
2985QualType ASTContext::getPromotedIntegerType(QualType Promotable) {
2986  assert(!Promotable.isNull());
2987  assert(Promotable->isPromotableIntegerType());
2988  if (const EnumType *ET = Promotable->getAs<EnumType>())
2989    return ET->getDecl()->getPromotionType();
2990  if (Promotable->isSignedIntegerType())
2991    return IntTy;
2992  uint64_t PromotableSize = getTypeSize(Promotable);
2993  uint64_t IntSize = getTypeSize(IntTy);
2994  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
2995  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
2996}
2997
2998/// getIntegerTypeOrder - Returns the highest ranked integer type:
2999/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3000/// LHS < RHS, return -1.
3001int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) {
3002  Type *LHSC = getCanonicalType(LHS).getTypePtr();
3003  Type *RHSC = getCanonicalType(RHS).getTypePtr();
3004  if (LHSC == RHSC) return 0;
3005
3006  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3007  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3008
3009  unsigned LHSRank = getIntegerRank(LHSC);
3010  unsigned RHSRank = getIntegerRank(RHSC);
3011
3012  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3013    if (LHSRank == RHSRank) return 0;
3014    return LHSRank > RHSRank ? 1 : -1;
3015  }
3016
3017  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3018  if (LHSUnsigned) {
3019    // If the unsigned [LHS] type is larger, return it.
3020    if (LHSRank >= RHSRank)
3021      return 1;
3022
3023    // If the signed type can represent all values of the unsigned type, it
3024    // wins.  Because we are dealing with 2's complement and types that are
3025    // powers of two larger than each other, this is always safe.
3026    return -1;
3027  }
3028
3029  // If the unsigned [RHS] type is larger, return it.
3030  if (RHSRank >= LHSRank)
3031    return -1;
3032
3033  // If the signed type can represent all values of the unsigned type, it
3034  // wins.  Because we are dealing with 2's complement and types that are
3035  // powers of two larger than each other, this is always safe.
3036  return 1;
3037}
3038
3039static RecordDecl *
3040CreateRecordDecl(ASTContext &Ctx, RecordDecl::TagKind TK, DeclContext *DC,
3041                 SourceLocation L, IdentifierInfo *Id) {
3042  if (Ctx.getLangOptions().CPlusPlus)
3043    return CXXRecordDecl::Create(Ctx, TK, DC, L, Id);
3044  else
3045    return RecordDecl::Create(Ctx, TK, DC, L, Id);
3046}
3047
3048// getCFConstantStringType - Return the type used for constant CFStrings.
3049QualType ASTContext::getCFConstantStringType() {
3050  if (!CFConstantStringTypeDecl) {
3051    CFConstantStringTypeDecl =
3052      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3053                       &Idents.get("NSConstantString"));
3054    CFConstantStringTypeDecl->startDefinition();
3055
3056    QualType FieldTypes[4];
3057
3058    // const int *isa;
3059    FieldTypes[0] = getPointerType(IntTy.withConst());
3060    // int flags;
3061    FieldTypes[1] = IntTy;
3062    // const char *str;
3063    FieldTypes[2] = getPointerType(CharTy.withConst());
3064    // long length;
3065    FieldTypes[3] = LongTy;
3066
3067    // Create fields
3068    for (unsigned i = 0; i < 4; ++i) {
3069      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3070                                           SourceLocation(), 0,
3071                                           FieldTypes[i], /*TInfo=*/0,
3072                                           /*BitWidth=*/0,
3073                                           /*Mutable=*/false);
3074      Field->setAccess(AS_public);
3075      CFConstantStringTypeDecl->addDecl(Field);
3076    }
3077
3078    CFConstantStringTypeDecl->completeDefinition();
3079  }
3080
3081  return getTagDeclType(CFConstantStringTypeDecl);
3082}
3083
3084void ASTContext::setCFConstantStringType(QualType T) {
3085  const RecordType *Rec = T->getAs<RecordType>();
3086  assert(Rec && "Invalid CFConstantStringType");
3087  CFConstantStringTypeDecl = Rec->getDecl();
3088}
3089
3090// getNSConstantStringType - Return the type used for constant NSStrings.
3091QualType ASTContext::getNSConstantStringType() {
3092  if (!NSConstantStringTypeDecl) {
3093    NSConstantStringTypeDecl =
3094    CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3095                     &Idents.get("__builtin_NSString"));
3096    NSConstantStringTypeDecl->startDefinition();
3097
3098    QualType FieldTypes[3];
3099
3100    // const int *isa;
3101    FieldTypes[0] = getPointerType(IntTy.withConst());
3102    // const char *str;
3103    FieldTypes[1] = getPointerType(CharTy.withConst());
3104    // unsigned int length;
3105    FieldTypes[2] = UnsignedIntTy;
3106
3107    // Create fields
3108    for (unsigned i = 0; i < 3; ++i) {
3109      FieldDecl *Field = FieldDecl::Create(*this, NSConstantStringTypeDecl,
3110                                           SourceLocation(), 0,
3111                                           FieldTypes[i], /*TInfo=*/0,
3112                                           /*BitWidth=*/0,
3113                                           /*Mutable=*/false);
3114      Field->setAccess(AS_public);
3115      NSConstantStringTypeDecl->addDecl(Field);
3116    }
3117
3118    NSConstantStringTypeDecl->completeDefinition();
3119  }
3120
3121  return getTagDeclType(NSConstantStringTypeDecl);
3122}
3123
3124void ASTContext::setNSConstantStringType(QualType T) {
3125  const RecordType *Rec = T->getAs<RecordType>();
3126  assert(Rec && "Invalid NSConstantStringType");
3127  NSConstantStringTypeDecl = Rec->getDecl();
3128}
3129
3130QualType ASTContext::getObjCFastEnumerationStateType() {
3131  if (!ObjCFastEnumerationStateTypeDecl) {
3132    ObjCFastEnumerationStateTypeDecl =
3133      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3134                       &Idents.get("__objcFastEnumerationState"));
3135    ObjCFastEnumerationStateTypeDecl->startDefinition();
3136
3137    QualType FieldTypes[] = {
3138      UnsignedLongTy,
3139      getPointerType(ObjCIdTypedefType),
3140      getPointerType(UnsignedLongTy),
3141      getConstantArrayType(UnsignedLongTy,
3142                           llvm::APInt(32, 5), ArrayType::Normal, 0)
3143    };
3144
3145    for (size_t i = 0; i < 4; ++i) {
3146      FieldDecl *Field = FieldDecl::Create(*this,
3147                                           ObjCFastEnumerationStateTypeDecl,
3148                                           SourceLocation(), 0,
3149                                           FieldTypes[i], /*TInfo=*/0,
3150                                           /*BitWidth=*/0,
3151                                           /*Mutable=*/false);
3152      Field->setAccess(AS_public);
3153      ObjCFastEnumerationStateTypeDecl->addDecl(Field);
3154    }
3155
3156    ObjCFastEnumerationStateTypeDecl->completeDefinition();
3157  }
3158
3159  return getTagDeclType(ObjCFastEnumerationStateTypeDecl);
3160}
3161
3162QualType ASTContext::getBlockDescriptorType() {
3163  if (BlockDescriptorType)
3164    return getTagDeclType(BlockDescriptorType);
3165
3166  RecordDecl *T;
3167  // FIXME: Needs the FlagAppleBlock bit.
3168  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3169                       &Idents.get("__block_descriptor"));
3170  T->startDefinition();
3171
3172  QualType FieldTypes[] = {
3173    UnsignedLongTy,
3174    UnsignedLongTy,
3175  };
3176
3177  const char *FieldNames[] = {
3178    "reserved",
3179    "Size"
3180  };
3181
3182  for (size_t i = 0; i < 2; ++i) {
3183    FieldDecl *Field = FieldDecl::Create(*this,
3184                                         T,
3185                                         SourceLocation(),
3186                                         &Idents.get(FieldNames[i]),
3187                                         FieldTypes[i], /*TInfo=*/0,
3188                                         /*BitWidth=*/0,
3189                                         /*Mutable=*/false);
3190    Field->setAccess(AS_public);
3191    T->addDecl(Field);
3192  }
3193
3194  T->completeDefinition();
3195
3196  BlockDescriptorType = T;
3197
3198  return getTagDeclType(BlockDescriptorType);
3199}
3200
3201void ASTContext::setBlockDescriptorType(QualType T) {
3202  const RecordType *Rec = T->getAs<RecordType>();
3203  assert(Rec && "Invalid BlockDescriptorType");
3204  BlockDescriptorType = Rec->getDecl();
3205}
3206
3207QualType ASTContext::getBlockDescriptorExtendedType() {
3208  if (BlockDescriptorExtendedType)
3209    return getTagDeclType(BlockDescriptorExtendedType);
3210
3211  RecordDecl *T;
3212  // FIXME: Needs the FlagAppleBlock bit.
3213  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3214                       &Idents.get("__block_descriptor_withcopydispose"));
3215  T->startDefinition();
3216
3217  QualType FieldTypes[] = {
3218    UnsignedLongTy,
3219    UnsignedLongTy,
3220    getPointerType(VoidPtrTy),
3221    getPointerType(VoidPtrTy)
3222  };
3223
3224  const char *FieldNames[] = {
3225    "reserved",
3226    "Size",
3227    "CopyFuncPtr",
3228    "DestroyFuncPtr"
3229  };
3230
3231  for (size_t i = 0; i < 4; ++i) {
3232    FieldDecl *Field = FieldDecl::Create(*this,
3233                                         T,
3234                                         SourceLocation(),
3235                                         &Idents.get(FieldNames[i]),
3236                                         FieldTypes[i], /*TInfo=*/0,
3237                                         /*BitWidth=*/0,
3238                                         /*Mutable=*/false);
3239    Field->setAccess(AS_public);
3240    T->addDecl(Field);
3241  }
3242
3243  T->completeDefinition();
3244
3245  BlockDescriptorExtendedType = T;
3246
3247  return getTagDeclType(BlockDescriptorExtendedType);
3248}
3249
3250void ASTContext::setBlockDescriptorExtendedType(QualType T) {
3251  const RecordType *Rec = T->getAs<RecordType>();
3252  assert(Rec && "Invalid BlockDescriptorType");
3253  BlockDescriptorExtendedType = Rec->getDecl();
3254}
3255
3256bool ASTContext::BlockRequiresCopying(QualType Ty) {
3257  if (Ty->isBlockPointerType())
3258    return true;
3259  if (isObjCNSObjectType(Ty))
3260    return true;
3261  if (Ty->isObjCObjectPointerType())
3262    return true;
3263  return false;
3264}
3265
3266QualType ASTContext::BuildByRefType(llvm::StringRef DeclName, QualType Ty) {
3267  //  type = struct __Block_byref_1_X {
3268  //    void *__isa;
3269  //    struct __Block_byref_1_X *__forwarding;
3270  //    unsigned int __flags;
3271  //    unsigned int __size;
3272  //    void *__copy_helper;            // as needed
3273  //    void *__destroy_help            // as needed
3274  //    int X;
3275  //  } *
3276
3277  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3278
3279  // FIXME: Move up
3280  llvm::SmallString<36> Name;
3281  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3282                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3283  RecordDecl *T;
3284  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3285                       &Idents.get(Name.str()));
3286  T->startDefinition();
3287  QualType Int32Ty = IntTy;
3288  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3289  QualType FieldTypes[] = {
3290    getPointerType(VoidPtrTy),
3291    getPointerType(getTagDeclType(T)),
3292    Int32Ty,
3293    Int32Ty,
3294    getPointerType(VoidPtrTy),
3295    getPointerType(VoidPtrTy),
3296    Ty
3297  };
3298
3299  llvm::StringRef FieldNames[] = {
3300    "__isa",
3301    "__forwarding",
3302    "__flags",
3303    "__size",
3304    "__copy_helper",
3305    "__destroy_helper",
3306    DeclName,
3307  };
3308
3309  for (size_t i = 0; i < 7; ++i) {
3310    if (!HasCopyAndDispose && i >=4 && i <= 5)
3311      continue;
3312    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3313                                         &Idents.get(FieldNames[i]),
3314                                         FieldTypes[i], /*TInfo=*/0,
3315                                         /*BitWidth=*/0, /*Mutable=*/false);
3316    Field->setAccess(AS_public);
3317    T->addDecl(Field);
3318  }
3319
3320  T->completeDefinition();
3321
3322  return getPointerType(getTagDeclType(T));
3323}
3324
3325
3326QualType ASTContext::getBlockParmType(
3327  bool BlockHasCopyDispose,
3328  llvm::SmallVectorImpl<const Expr *> &Layout) {
3329
3330  // FIXME: Move up
3331  llvm::SmallString<36> Name;
3332  llvm::raw_svector_ostream(Name) << "__block_literal_"
3333                                  << ++UniqueBlockParmTypeID;
3334  RecordDecl *T;
3335  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3336                       &Idents.get(Name.str()));
3337  T->startDefinition();
3338  QualType FieldTypes[] = {
3339    getPointerType(VoidPtrTy),
3340    IntTy,
3341    IntTy,
3342    getPointerType(VoidPtrTy),
3343    (BlockHasCopyDispose ?
3344     getPointerType(getBlockDescriptorExtendedType()) :
3345     getPointerType(getBlockDescriptorType()))
3346  };
3347
3348  const char *FieldNames[] = {
3349    "__isa",
3350    "__flags",
3351    "__reserved",
3352    "__FuncPtr",
3353    "__descriptor"
3354  };
3355
3356  for (size_t i = 0; i < 5; ++i) {
3357    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3358                                         &Idents.get(FieldNames[i]),
3359                                         FieldTypes[i], /*TInfo=*/0,
3360                                         /*BitWidth=*/0, /*Mutable=*/false);
3361    Field->setAccess(AS_public);
3362    T->addDecl(Field);
3363  }
3364
3365  for (unsigned i = 0; i < Layout.size(); ++i) {
3366    const Expr *E = Layout[i];
3367
3368    QualType FieldType = E->getType();
3369    IdentifierInfo *FieldName = 0;
3370    if (isa<CXXThisExpr>(E)) {
3371      FieldName = &Idents.get("this");
3372    } else if (const BlockDeclRefExpr *BDRE = dyn_cast<BlockDeclRefExpr>(E)) {
3373      const ValueDecl *D = BDRE->getDecl();
3374      FieldName = D->getIdentifier();
3375      if (BDRE->isByRef())
3376        FieldType = BuildByRefType(D->getName(), FieldType);
3377    } else {
3378      // Padding.
3379      assert(isa<ConstantArrayType>(FieldType) &&
3380             isa<DeclRefExpr>(E) &&
3381             !cast<DeclRefExpr>(E)->getDecl()->getDeclName() &&
3382             "doesn't match characteristics of padding decl");
3383    }
3384
3385    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3386                                         FieldName, FieldType, /*TInfo=*/0,
3387                                         /*BitWidth=*/0, /*Mutable=*/false);
3388    Field->setAccess(AS_public);
3389    T->addDecl(Field);
3390  }
3391
3392  T->completeDefinition();
3393
3394  return getPointerType(getTagDeclType(T));
3395}
3396
3397void ASTContext::setObjCFastEnumerationStateType(QualType T) {
3398  const RecordType *Rec = T->getAs<RecordType>();
3399  assert(Rec && "Invalid ObjCFAstEnumerationStateType");
3400  ObjCFastEnumerationStateTypeDecl = Rec->getDecl();
3401}
3402
3403// This returns true if a type has been typedefed to BOOL:
3404// typedef <type> BOOL;
3405static bool isTypeTypedefedAsBOOL(QualType T) {
3406  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3407    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3408      return II->isStr("BOOL");
3409
3410  return false;
3411}
3412
3413/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3414/// purpose.
3415CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) {
3416  CharUnits sz = getTypeSizeInChars(type);
3417
3418  // Make all integer and enum types at least as large as an int
3419  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3420    sz = std::max(sz, getTypeSizeInChars(IntTy));
3421  // Treat arrays as pointers, since that's how they're passed in.
3422  else if (type->isArrayType())
3423    sz = getTypeSizeInChars(VoidPtrTy);
3424  return sz;
3425}
3426
3427static inline
3428std::string charUnitsToString(const CharUnits &CU) {
3429  return llvm::itostr(CU.getQuantity());
3430}
3431
3432/// getObjCEncodingForBlockDecl - Return the encoded type for this block
3433/// declaration.
3434void ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr,
3435                                             std::string& S) {
3436  const BlockDecl *Decl = Expr->getBlockDecl();
3437  QualType BlockTy =
3438      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3439  // Encode result type.
3440  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3441  // Compute size of all parameters.
3442  // Start with computing size of a pointer in number of bytes.
3443  // FIXME: There might(should) be a better way of doing this computation!
3444  SourceLocation Loc;
3445  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3446  CharUnits ParmOffset = PtrSize;
3447  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3448       E = Decl->param_end(); PI != E; ++PI) {
3449    QualType PType = (*PI)->getType();
3450    CharUnits sz = getObjCEncodingTypeSize(PType);
3451    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3452    ParmOffset += sz;
3453  }
3454  // Size of the argument frame
3455  S += charUnitsToString(ParmOffset);
3456  // Block pointer and offset.
3457  S += "@?0";
3458  ParmOffset = PtrSize;
3459
3460  // Argument types.
3461  ParmOffset = PtrSize;
3462  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3463       Decl->param_end(); PI != E; ++PI) {
3464    ParmVarDecl *PVDecl = *PI;
3465    QualType PType = PVDecl->getOriginalType();
3466    if (const ArrayType *AT =
3467          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3468      // Use array's original type only if it has known number of
3469      // elements.
3470      if (!isa<ConstantArrayType>(AT))
3471        PType = PVDecl->getType();
3472    } else if (PType->isFunctionType())
3473      PType = PVDecl->getType();
3474    getObjCEncodingForType(PType, S);
3475    S += charUnitsToString(ParmOffset);
3476    ParmOffset += getObjCEncodingTypeSize(PType);
3477  }
3478}
3479
3480/// getObjCEncodingForMethodDecl - Return the encoded type for this method
3481/// declaration.
3482void ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
3483                                              std::string& S) {
3484  // FIXME: This is not very efficient.
3485  // Encode type qualifer, 'in', 'inout', etc. for the return type.
3486  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
3487  // Encode result type.
3488  getObjCEncodingForType(Decl->getResultType(), S);
3489  // Compute size of all parameters.
3490  // Start with computing size of a pointer in number of bytes.
3491  // FIXME: There might(should) be a better way of doing this computation!
3492  SourceLocation Loc;
3493  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3494  // The first two arguments (self and _cmd) are pointers; account for
3495  // their size.
3496  CharUnits ParmOffset = 2 * PtrSize;
3497  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3498       E = Decl->sel_param_end(); PI != E; ++PI) {
3499    QualType PType = (*PI)->getType();
3500    CharUnits sz = getObjCEncodingTypeSize(PType);
3501    assert (sz.isPositive() &&
3502        "getObjCEncodingForMethodDecl - Incomplete param type");
3503    ParmOffset += sz;
3504  }
3505  S += charUnitsToString(ParmOffset);
3506  S += "@0:";
3507  S += charUnitsToString(PtrSize);
3508
3509  // Argument types.
3510  ParmOffset = 2 * PtrSize;
3511  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3512       E = Decl->sel_param_end(); PI != E; ++PI) {
3513    ParmVarDecl *PVDecl = *PI;
3514    QualType PType = PVDecl->getOriginalType();
3515    if (const ArrayType *AT =
3516          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3517      // Use array's original type only if it has known number of
3518      // elements.
3519      if (!isa<ConstantArrayType>(AT))
3520        PType = PVDecl->getType();
3521    } else if (PType->isFunctionType())
3522      PType = PVDecl->getType();
3523    // Process argument qualifiers for user supplied arguments; such as,
3524    // 'in', 'inout', etc.
3525    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
3526    getObjCEncodingForType(PType, S);
3527    S += charUnitsToString(ParmOffset);
3528    ParmOffset += getObjCEncodingTypeSize(PType);
3529  }
3530}
3531
3532/// getObjCEncodingForPropertyDecl - Return the encoded type for this
3533/// property declaration. If non-NULL, Container must be either an
3534/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
3535/// NULL when getting encodings for protocol properties.
3536/// Property attributes are stored as a comma-delimited C string. The simple
3537/// attributes readonly and bycopy are encoded as single characters. The
3538/// parametrized attributes, getter=name, setter=name, and ivar=name, are
3539/// encoded as single characters, followed by an identifier. Property types
3540/// are also encoded as a parametrized attribute. The characters used to encode
3541/// these attributes are defined by the following enumeration:
3542/// @code
3543/// enum PropertyAttributes {
3544/// kPropertyReadOnly = 'R',   // property is read-only.
3545/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
3546/// kPropertyByref = '&',  // property is a reference to the value last assigned
3547/// kPropertyDynamic = 'D',    // property is dynamic
3548/// kPropertyGetter = 'G',     // followed by getter selector name
3549/// kPropertySetter = 'S',     // followed by setter selector name
3550/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
3551/// kPropertyType = 't'              // followed by old-style type encoding.
3552/// kPropertyWeak = 'W'              // 'weak' property
3553/// kPropertyStrong = 'P'            // property GC'able
3554/// kPropertyNonAtomic = 'N'         // property non-atomic
3555/// };
3556/// @endcode
3557void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
3558                                                const Decl *Container,
3559                                                std::string& S) {
3560  // Collect information from the property implementation decl(s).
3561  bool Dynamic = false;
3562  ObjCPropertyImplDecl *SynthesizePID = 0;
3563
3564  // FIXME: Duplicated code due to poor abstraction.
3565  if (Container) {
3566    if (const ObjCCategoryImplDecl *CID =
3567        dyn_cast<ObjCCategoryImplDecl>(Container)) {
3568      for (ObjCCategoryImplDecl::propimpl_iterator
3569             i = CID->propimpl_begin(), e = CID->propimpl_end();
3570           i != e; ++i) {
3571        ObjCPropertyImplDecl *PID = *i;
3572        if (PID->getPropertyDecl() == PD) {
3573          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3574            Dynamic = true;
3575          } else {
3576            SynthesizePID = PID;
3577          }
3578        }
3579      }
3580    } else {
3581      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
3582      for (ObjCCategoryImplDecl::propimpl_iterator
3583             i = OID->propimpl_begin(), e = OID->propimpl_end();
3584           i != e; ++i) {
3585        ObjCPropertyImplDecl *PID = *i;
3586        if (PID->getPropertyDecl() == PD) {
3587          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3588            Dynamic = true;
3589          } else {
3590            SynthesizePID = PID;
3591          }
3592        }
3593      }
3594    }
3595  }
3596
3597  // FIXME: This is not very efficient.
3598  S = "T";
3599
3600  // Encode result type.
3601  // GCC has some special rules regarding encoding of properties which
3602  // closely resembles encoding of ivars.
3603  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
3604                             true /* outermost type */,
3605                             true /* encoding for property */);
3606
3607  if (PD->isReadOnly()) {
3608    S += ",R";
3609  } else {
3610    switch (PD->getSetterKind()) {
3611    case ObjCPropertyDecl::Assign: break;
3612    case ObjCPropertyDecl::Copy:   S += ",C"; break;
3613    case ObjCPropertyDecl::Retain: S += ",&"; break;
3614    }
3615  }
3616
3617  // It really isn't clear at all what this means, since properties
3618  // are "dynamic by default".
3619  if (Dynamic)
3620    S += ",D";
3621
3622  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
3623    S += ",N";
3624
3625  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
3626    S += ",G";
3627    S += PD->getGetterName().getAsString();
3628  }
3629
3630  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
3631    S += ",S";
3632    S += PD->getSetterName().getAsString();
3633  }
3634
3635  if (SynthesizePID) {
3636    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
3637    S += ",V";
3638    S += OID->getNameAsString();
3639  }
3640
3641  // FIXME: OBJCGC: weak & strong
3642}
3643
3644/// getLegacyIntegralTypeEncoding -
3645/// Another legacy compatibility encoding: 32-bit longs are encoded as
3646/// 'l' or 'L' , but not always.  For typedefs, we need to use
3647/// 'i' or 'I' instead if encoding a struct field, or a pointer!
3648///
3649void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
3650  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
3651    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
3652      if (BT->getKind() == BuiltinType::ULong &&
3653          ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3654        PointeeTy = UnsignedIntTy;
3655      else
3656        if (BT->getKind() == BuiltinType::Long &&
3657            ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3658          PointeeTy = IntTy;
3659    }
3660  }
3661}
3662
3663void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
3664                                        const FieldDecl *Field) {
3665  // We follow the behavior of gcc, expanding structures which are
3666  // directly pointed to, and expanding embedded structures. Note that
3667  // these rules are sufficient to prevent recursive encoding of the
3668  // same type.
3669  getObjCEncodingForTypeImpl(T, S, true, true, Field,
3670                             true /* outermost type */);
3671}
3672
3673static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
3674    switch (T->getAs<BuiltinType>()->getKind()) {
3675    default: assert(0 && "Unhandled builtin type kind");
3676    case BuiltinType::Void:       return 'v';
3677    case BuiltinType::Bool:       return 'B';
3678    case BuiltinType::Char_U:
3679    case BuiltinType::UChar:      return 'C';
3680    case BuiltinType::UShort:     return 'S';
3681    case BuiltinType::UInt:       return 'I';
3682    case BuiltinType::ULong:
3683        return
3684          (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'L' : 'Q';
3685    case BuiltinType::UInt128:    return 'T';
3686    case BuiltinType::ULongLong:  return 'Q';
3687    case BuiltinType::Char_S:
3688    case BuiltinType::SChar:      return 'c';
3689    case BuiltinType::Short:      return 's';
3690    case BuiltinType::WChar:
3691    case BuiltinType::Int:        return 'i';
3692    case BuiltinType::Long:
3693      return
3694        (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'l' : 'q';
3695    case BuiltinType::LongLong:   return 'q';
3696    case BuiltinType::Int128:     return 't';
3697    case BuiltinType::Float:      return 'f';
3698    case BuiltinType::Double:     return 'd';
3699    case BuiltinType::LongDouble: return 'D';
3700    }
3701}
3702
3703static void EncodeBitField(const ASTContext *Context, std::string& S,
3704                           QualType T, const FieldDecl *FD) {
3705  const Expr *E = FD->getBitWidth();
3706  assert(E && "bitfield width not there - getObjCEncodingForTypeImpl");
3707  ASTContext *Ctx = const_cast<ASTContext*>(Context);
3708  S += 'b';
3709  // The NeXT runtime encodes bit fields as b followed by the number of bits.
3710  // The GNU runtime requires more information; bitfields are encoded as b,
3711  // then the offset (in bits) of the first element, then the type of the
3712  // bitfield, then the size in bits.  For example, in this structure:
3713  //
3714  // struct
3715  // {
3716  //    int integer;
3717  //    int flags:2;
3718  // };
3719  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
3720  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
3721  // information is not especially sensible, but we're stuck with it for
3722  // compatibility with GCC, although providing it breaks anything that
3723  // actually uses runtime introspection and wants to work on both runtimes...
3724  if (!Ctx->getLangOptions().NeXTRuntime) {
3725    const RecordDecl *RD = FD->getParent();
3726    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
3727    // FIXME: This same linear search is also used in ExprConstant - it might
3728    // be better if the FieldDecl stored its offset.  We'd be increasing the
3729    // size of the object slightly, but saving some time every time it is used.
3730    unsigned i = 0;
3731    for (RecordDecl::field_iterator Field = RD->field_begin(),
3732                                 FieldEnd = RD->field_end();
3733         Field != FieldEnd; (void)++Field, ++i) {
3734      if (*Field == FD)
3735        break;
3736    }
3737    S += llvm::utostr(RL.getFieldOffset(i));
3738    S += ObjCEncodingForPrimitiveKind(Context, T);
3739  }
3740  unsigned N = E->EvaluateAsInt(*Ctx).getZExtValue();
3741  S += llvm::utostr(N);
3742}
3743
3744// FIXME: Use SmallString for accumulating string.
3745void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
3746                                            bool ExpandPointedToStructures,
3747                                            bool ExpandStructures,
3748                                            const FieldDecl *FD,
3749                                            bool OutermostType,
3750                                            bool EncodingProperty) {
3751  if (T->getAs<BuiltinType>()) {
3752    if (FD && FD->isBitField())
3753      return EncodeBitField(this, S, T, FD);
3754    S += ObjCEncodingForPrimitiveKind(this, T);
3755    return;
3756  }
3757
3758  if (const ComplexType *CT = T->getAs<ComplexType>()) {
3759    S += 'j';
3760    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
3761                               false);
3762    return;
3763  }
3764
3765  // encoding for pointer or r3eference types.
3766  QualType PointeeTy;
3767  if (const PointerType *PT = T->getAs<PointerType>()) {
3768    if (PT->isObjCSelType()) {
3769      S += ':';
3770      return;
3771    }
3772    PointeeTy = PT->getPointeeType();
3773  }
3774  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3775    PointeeTy = RT->getPointeeType();
3776  if (!PointeeTy.isNull()) {
3777    bool isReadOnly = false;
3778    // For historical/compatibility reasons, the read-only qualifier of the
3779    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
3780    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
3781    // Also, do not emit the 'r' for anything but the outermost type!
3782    if (isa<TypedefType>(T.getTypePtr())) {
3783      if (OutermostType && T.isConstQualified()) {
3784        isReadOnly = true;
3785        S += 'r';
3786      }
3787    } else if (OutermostType) {
3788      QualType P = PointeeTy;
3789      while (P->getAs<PointerType>())
3790        P = P->getAs<PointerType>()->getPointeeType();
3791      if (P.isConstQualified()) {
3792        isReadOnly = true;
3793        S += 'r';
3794      }
3795    }
3796    if (isReadOnly) {
3797      // Another legacy compatibility encoding. Some ObjC qualifier and type
3798      // combinations need to be rearranged.
3799      // Rewrite "in const" from "nr" to "rn"
3800      if (llvm::StringRef(S).endswith("nr"))
3801        S.replace(S.end()-2, S.end(), "rn");
3802    }
3803
3804    if (PointeeTy->isCharType()) {
3805      // char pointer types should be encoded as '*' unless it is a
3806      // type that has been typedef'd to 'BOOL'.
3807      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
3808        S += '*';
3809        return;
3810      }
3811    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
3812      // GCC binary compat: Need to convert "struct objc_class *" to "#".
3813      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
3814        S += '#';
3815        return;
3816      }
3817      // GCC binary compat: Need to convert "struct objc_object *" to "@".
3818      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
3819        S += '@';
3820        return;
3821      }
3822      // fall through...
3823    }
3824    S += '^';
3825    getLegacyIntegralTypeEncoding(PointeeTy);
3826
3827    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
3828                               NULL);
3829    return;
3830  }
3831
3832  if (const ArrayType *AT =
3833      // Ignore type qualifiers etc.
3834        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
3835    if (isa<IncompleteArrayType>(AT)) {
3836      // Incomplete arrays are encoded as a pointer to the array element.
3837      S += '^';
3838
3839      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3840                                 false, ExpandStructures, FD);
3841    } else {
3842      S += '[';
3843
3844      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
3845        S += llvm::utostr(CAT->getSize().getZExtValue());
3846      else {
3847        //Variable length arrays are encoded as a regular array with 0 elements.
3848        assert(isa<VariableArrayType>(AT) && "Unknown array type!");
3849        S += '0';
3850      }
3851
3852      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3853                                 false, ExpandStructures, FD);
3854      S += ']';
3855    }
3856    return;
3857  }
3858
3859  if (T->getAs<FunctionType>()) {
3860    S += '?';
3861    return;
3862  }
3863
3864  if (const RecordType *RTy = T->getAs<RecordType>()) {
3865    RecordDecl *RDecl = RTy->getDecl();
3866    S += RDecl->isUnion() ? '(' : '{';
3867    // Anonymous structures print as '?'
3868    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
3869      S += II->getName();
3870      if (ClassTemplateSpecializationDecl *Spec
3871          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
3872        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
3873        std::string TemplateArgsStr
3874          = TemplateSpecializationType::PrintTemplateArgumentList(
3875                                            TemplateArgs.getFlatArgumentList(),
3876                                            TemplateArgs.flat_size(),
3877                                            (*this).PrintingPolicy);
3878
3879        S += TemplateArgsStr;
3880      }
3881    } else {
3882      S += '?';
3883    }
3884    if (ExpandStructures) {
3885      S += '=';
3886      for (RecordDecl::field_iterator Field = RDecl->field_begin(),
3887                                   FieldEnd = RDecl->field_end();
3888           Field != FieldEnd; ++Field) {
3889        if (FD) {
3890          S += '"';
3891          S += Field->getNameAsString();
3892          S += '"';
3893        }
3894
3895        // Special case bit-fields.
3896        if (Field->isBitField()) {
3897          getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
3898                                     (*Field));
3899        } else {
3900          QualType qt = Field->getType();
3901          getLegacyIntegralTypeEncoding(qt);
3902          getObjCEncodingForTypeImpl(qt, S, false, true,
3903                                     FD);
3904        }
3905      }
3906    }
3907    S += RDecl->isUnion() ? ')' : '}';
3908    return;
3909  }
3910
3911  if (T->isEnumeralType()) {
3912    if (FD && FD->isBitField())
3913      EncodeBitField(this, S, T, FD);
3914    else
3915      S += 'i';
3916    return;
3917  }
3918
3919  if (T->isBlockPointerType()) {
3920    S += "@?"; // Unlike a pointer-to-function, which is "^?".
3921    return;
3922  }
3923
3924  // Ignore protocol qualifiers when mangling at this level.
3925  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
3926    T = OT->getBaseType();
3927
3928  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
3929    // @encode(class_name)
3930    ObjCInterfaceDecl *OI = OIT->getDecl();
3931    S += '{';
3932    const IdentifierInfo *II = OI->getIdentifier();
3933    S += II->getName();
3934    S += '=';
3935    llvm::SmallVector<ObjCIvarDecl*, 32> Ivars;
3936    DeepCollectObjCIvars(OI, true, Ivars);
3937    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
3938      FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
3939      if (Field->isBitField())
3940        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
3941      else
3942        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
3943    }
3944    S += '}';
3945    return;
3946  }
3947
3948  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
3949    if (OPT->isObjCIdType()) {
3950      S += '@';
3951      return;
3952    }
3953
3954    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
3955      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
3956      // Since this is a binary compatibility issue, need to consult with runtime
3957      // folks. Fortunately, this is a *very* obsure construct.
3958      S += '#';
3959      return;
3960    }
3961
3962    if (OPT->isObjCQualifiedIdType()) {
3963      getObjCEncodingForTypeImpl(getObjCIdType(), S,
3964                                 ExpandPointedToStructures,
3965                                 ExpandStructures, FD);
3966      if (FD || EncodingProperty) {
3967        // Note that we do extended encoding of protocol qualifer list
3968        // Only when doing ivar or property encoding.
3969        S += '"';
3970        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3971             E = OPT->qual_end(); I != E; ++I) {
3972          S += '<';
3973          S += (*I)->getNameAsString();
3974          S += '>';
3975        }
3976        S += '"';
3977      }
3978      return;
3979    }
3980
3981    QualType PointeeTy = OPT->getPointeeType();
3982    if (!EncodingProperty &&
3983        isa<TypedefType>(PointeeTy.getTypePtr())) {
3984      // Another historical/compatibility reason.
3985      // We encode the underlying type which comes out as
3986      // {...};
3987      S += '^';
3988      getObjCEncodingForTypeImpl(PointeeTy, S,
3989                                 false, ExpandPointedToStructures,
3990                                 NULL);
3991      return;
3992    }
3993
3994    S += '@';
3995    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
3996      S += '"';
3997      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
3998      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3999           E = OPT->qual_end(); I != E; ++I) {
4000        S += '<';
4001        S += (*I)->getNameAsString();
4002        S += '>';
4003      }
4004      S += '"';
4005    }
4006    return;
4007  }
4008
4009  // gcc just blithely ignores member pointers.
4010  // TODO: maybe there should be a mangling for these
4011  if (T->getAs<MemberPointerType>())
4012    return;
4013
4014  if (T->isVectorType()) {
4015    // This matches gcc's encoding, even though technically it is
4016    // insufficient.
4017    // FIXME. We should do a better job than gcc.
4018    return;
4019  }
4020
4021  assert(0 && "@encode for type not implemented!");
4022}
4023
4024void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4025                                                 std::string& S) const {
4026  if (QT & Decl::OBJC_TQ_In)
4027    S += 'n';
4028  if (QT & Decl::OBJC_TQ_Inout)
4029    S += 'N';
4030  if (QT & Decl::OBJC_TQ_Out)
4031    S += 'o';
4032  if (QT & Decl::OBJC_TQ_Bycopy)
4033    S += 'O';
4034  if (QT & Decl::OBJC_TQ_Byref)
4035    S += 'R';
4036  if (QT & Decl::OBJC_TQ_Oneway)
4037    S += 'V';
4038}
4039
4040void ASTContext::setBuiltinVaListType(QualType T) {
4041  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4042
4043  BuiltinVaListType = T;
4044}
4045
4046void ASTContext::setObjCIdType(QualType T) {
4047  ObjCIdTypedefType = T;
4048}
4049
4050void ASTContext::setObjCSelType(QualType T) {
4051  ObjCSelTypedefType = T;
4052}
4053
4054void ASTContext::setObjCProtoType(QualType QT) {
4055  ObjCProtoType = QT;
4056}
4057
4058void ASTContext::setObjCClassType(QualType T) {
4059  ObjCClassTypedefType = T;
4060}
4061
4062void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4063  assert(ObjCConstantStringType.isNull() &&
4064         "'NSConstantString' type already set!");
4065
4066  ObjCConstantStringType = getObjCInterfaceType(Decl);
4067}
4068
4069/// \brief Retrieve the template name that corresponds to a non-empty
4070/// lookup.
4071TemplateName ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4072                                                   UnresolvedSetIterator End) {
4073  unsigned size = End - Begin;
4074  assert(size > 1 && "set is not overloaded!");
4075
4076  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4077                          size * sizeof(FunctionTemplateDecl*));
4078  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4079
4080  NamedDecl **Storage = OT->getStorage();
4081  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4082    NamedDecl *D = *I;
4083    assert(isa<FunctionTemplateDecl>(D) ||
4084           (isa<UsingShadowDecl>(D) &&
4085            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4086    *Storage++ = D;
4087  }
4088
4089  return TemplateName(OT);
4090}
4091
4092/// \brief Retrieve the template name that represents a qualified
4093/// template name such as \c std::vector.
4094TemplateName ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4095                                                  bool TemplateKeyword,
4096                                                  TemplateDecl *Template) {
4097  // FIXME: Canonicalization?
4098  llvm::FoldingSetNodeID ID;
4099  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4100
4101  void *InsertPos = 0;
4102  QualifiedTemplateName *QTN =
4103    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4104  if (!QTN) {
4105    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4106    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4107  }
4108
4109  return TemplateName(QTN);
4110}
4111
4112/// \brief Retrieve the template name that represents a dependent
4113/// template name such as \c MetaFun::template apply.
4114TemplateName ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4115                                                  const IdentifierInfo *Name) {
4116  assert((!NNS || NNS->isDependent()) &&
4117         "Nested name specifier must be dependent");
4118
4119  llvm::FoldingSetNodeID ID;
4120  DependentTemplateName::Profile(ID, NNS, Name);
4121
4122  void *InsertPos = 0;
4123  DependentTemplateName *QTN =
4124    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4125
4126  if (QTN)
4127    return TemplateName(QTN);
4128
4129  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4130  if (CanonNNS == NNS) {
4131    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4132  } else {
4133    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4134    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4135    DependentTemplateName *CheckQTN =
4136      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4137    assert(!CheckQTN && "Dependent type name canonicalization broken");
4138    (void)CheckQTN;
4139  }
4140
4141  DependentTemplateNames.InsertNode(QTN, InsertPos);
4142  return TemplateName(QTN);
4143}
4144
4145/// \brief Retrieve the template name that represents a dependent
4146/// template name such as \c MetaFun::template operator+.
4147TemplateName
4148ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4149                                     OverloadedOperatorKind Operator) {
4150  assert((!NNS || NNS->isDependent()) &&
4151         "Nested name specifier must be dependent");
4152
4153  llvm::FoldingSetNodeID ID;
4154  DependentTemplateName::Profile(ID, NNS, Operator);
4155
4156  void *InsertPos = 0;
4157  DependentTemplateName *QTN
4158    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4159
4160  if (QTN)
4161    return TemplateName(QTN);
4162
4163  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4164  if (CanonNNS == NNS) {
4165    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4166  } else {
4167    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4168    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4169
4170    DependentTemplateName *CheckQTN
4171      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4172    assert(!CheckQTN && "Dependent template name canonicalization broken");
4173    (void)CheckQTN;
4174  }
4175
4176  DependentTemplateNames.InsertNode(QTN, InsertPos);
4177  return TemplateName(QTN);
4178}
4179
4180/// getFromTargetType - Given one of the integer types provided by
4181/// TargetInfo, produce the corresponding type. The unsigned @p Type
4182/// is actually a value of type @c TargetInfo::IntType.
4183CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4184  switch (Type) {
4185  case TargetInfo::NoInt: return CanQualType();
4186  case TargetInfo::SignedShort: return ShortTy;
4187  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4188  case TargetInfo::SignedInt: return IntTy;
4189  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4190  case TargetInfo::SignedLong: return LongTy;
4191  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4192  case TargetInfo::SignedLongLong: return LongLongTy;
4193  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4194  }
4195
4196  assert(false && "Unhandled TargetInfo::IntType value");
4197  return CanQualType();
4198}
4199
4200//===----------------------------------------------------------------------===//
4201//                        Type Predicates.
4202//===----------------------------------------------------------------------===//
4203
4204/// isObjCNSObjectType - Return true if this is an NSObject object using
4205/// NSObject attribute on a c-style pointer type.
4206/// FIXME - Make it work directly on types.
4207/// FIXME: Move to Type.
4208///
4209bool ASTContext::isObjCNSObjectType(QualType Ty) const {
4210  if (TypedefType *TDT = dyn_cast<TypedefType>(Ty)) {
4211    if (TypedefDecl *TD = TDT->getDecl())
4212      if (TD->getAttr<ObjCNSObjectAttr>())
4213        return true;
4214  }
4215  return false;
4216}
4217
4218/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4219/// garbage collection attribute.
4220///
4221Qualifiers::GC ASTContext::getObjCGCAttrKind(const QualType &Ty) const {
4222  Qualifiers::GC GCAttrs = Qualifiers::GCNone;
4223  if (getLangOptions().ObjC1 &&
4224      getLangOptions().getGCMode() != LangOptions::NonGC) {
4225    GCAttrs = Ty.getObjCGCAttr();
4226    // Default behavious under objective-c's gc is for objective-c pointers
4227    // (or pointers to them) be treated as though they were declared
4228    // as __strong.
4229    if (GCAttrs == Qualifiers::GCNone) {
4230      if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4231        GCAttrs = Qualifiers::Strong;
4232      else if (Ty->isPointerType())
4233        return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4234    }
4235    // Non-pointers have none gc'able attribute regardless of the attribute
4236    // set on them.
4237    else if (!Ty->isAnyPointerType() && !Ty->isBlockPointerType())
4238      return Qualifiers::GCNone;
4239  }
4240  return GCAttrs;
4241}
4242
4243//===----------------------------------------------------------------------===//
4244//                        Type Compatibility Testing
4245//===----------------------------------------------------------------------===//
4246
4247/// areCompatVectorTypes - Return true if the two specified vector types are
4248/// compatible.
4249static bool areCompatVectorTypes(const VectorType *LHS,
4250                                 const VectorType *RHS) {
4251  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
4252  return LHS->getElementType() == RHS->getElementType() &&
4253         LHS->getNumElements() == RHS->getNumElements();
4254}
4255
4256bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
4257                                          QualType SecondVec) {
4258  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
4259  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
4260
4261  if (hasSameUnqualifiedType(FirstVec, SecondVec))
4262    return true;
4263
4264  // AltiVec vectors types are identical to equivalent GCC vector types
4265  const VectorType *First = FirstVec->getAs<VectorType>();
4266  const VectorType *Second = SecondVec->getAs<VectorType>();
4267  if ((((First->getAltiVecSpecific() == VectorType::AltiVec) &&
4268        (Second->getAltiVecSpecific() == VectorType::NotAltiVec)) ||
4269       ((First->getAltiVecSpecific() == VectorType::NotAltiVec) &&
4270        (Second->getAltiVecSpecific() == VectorType::AltiVec))) &&
4271      hasSameType(First->getElementType(), Second->getElementType()) &&
4272      (First->getNumElements() == Second->getNumElements()))
4273    return true;
4274
4275  return false;
4276}
4277
4278//===----------------------------------------------------------------------===//
4279// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
4280//===----------------------------------------------------------------------===//
4281
4282/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
4283/// inheritance hierarchy of 'rProto'.
4284bool ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
4285                                                ObjCProtocolDecl *rProto) {
4286  if (lProto == rProto)
4287    return true;
4288  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
4289       E = rProto->protocol_end(); PI != E; ++PI)
4290    if (ProtocolCompatibleWithProtocol(lProto, *PI))
4291      return true;
4292  return false;
4293}
4294
4295/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
4296/// return true if lhs's protocols conform to rhs's protocol; false
4297/// otherwise.
4298bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
4299  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
4300    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
4301  return false;
4302}
4303
4304/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
4305/// Class<p1, ...>.
4306bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
4307                                                      QualType rhs) {
4308  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
4309  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4310  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
4311
4312  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4313       E = lhsQID->qual_end(); I != E; ++I) {
4314    bool match = false;
4315    ObjCProtocolDecl *lhsProto = *I;
4316    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4317         E = rhsOPT->qual_end(); J != E; ++J) {
4318      ObjCProtocolDecl *rhsProto = *J;
4319      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
4320        match = true;
4321        break;
4322      }
4323    }
4324    if (!match)
4325      return false;
4326  }
4327  return true;
4328}
4329
4330/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
4331/// ObjCQualifiedIDType.
4332bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
4333                                                   bool compare) {
4334  // Allow id<P..> and an 'id' or void* type in all cases.
4335  if (lhs->isVoidPointerType() ||
4336      lhs->isObjCIdType() || lhs->isObjCClassType())
4337    return true;
4338  else if (rhs->isVoidPointerType() ||
4339           rhs->isObjCIdType() || rhs->isObjCClassType())
4340    return true;
4341
4342  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
4343    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4344
4345    if (!rhsOPT) return false;
4346
4347    if (rhsOPT->qual_empty()) {
4348      // If the RHS is a unqualified interface pointer "NSString*",
4349      // make sure we check the class hierarchy.
4350      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4351        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4352             E = lhsQID->qual_end(); I != E; ++I) {
4353          // when comparing an id<P> on lhs with a static type on rhs,
4354          // see if static class implements all of id's protocols, directly or
4355          // through its super class and categories.
4356          if (!rhsID->ClassImplementsProtocol(*I, true))
4357            return false;
4358        }
4359      }
4360      // If there are no qualifiers and no interface, we have an 'id'.
4361      return true;
4362    }
4363    // Both the right and left sides have qualifiers.
4364    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4365         E = lhsQID->qual_end(); I != E; ++I) {
4366      ObjCProtocolDecl *lhsProto = *I;
4367      bool match = false;
4368
4369      // when comparing an id<P> on lhs with a static type on rhs,
4370      // see if static class implements all of id's protocols, directly or
4371      // through its super class and categories.
4372      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4373           E = rhsOPT->qual_end(); J != E; ++J) {
4374        ObjCProtocolDecl *rhsProto = *J;
4375        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4376            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4377          match = true;
4378          break;
4379        }
4380      }
4381      // If the RHS is a qualified interface pointer "NSString<P>*",
4382      // make sure we check the class hierarchy.
4383      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4384        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4385             E = lhsQID->qual_end(); I != E; ++I) {
4386          // when comparing an id<P> on lhs with a static type on rhs,
4387          // see if static class implements all of id's protocols, directly or
4388          // through its super class and categories.
4389          if (rhsID->ClassImplementsProtocol(*I, true)) {
4390            match = true;
4391            break;
4392          }
4393        }
4394      }
4395      if (!match)
4396        return false;
4397    }
4398
4399    return true;
4400  }
4401
4402  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
4403  assert(rhsQID && "One of the LHS/RHS should be id<x>");
4404
4405  if (const ObjCObjectPointerType *lhsOPT =
4406        lhs->getAsObjCInterfacePointerType()) {
4407    if (lhsOPT->qual_empty()) {
4408      bool match = false;
4409      if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
4410        for (ObjCObjectPointerType::qual_iterator I = rhsQID->qual_begin(),
4411             E = rhsQID->qual_end(); I != E; ++I) {
4412          // when comparing an id<P> on rhs with a static type on lhs,
4413          // static class must implement all of id's protocols directly or
4414          // indirectly through its super class.
4415          if (lhsID->ClassImplementsProtocol(*I, true)) {
4416            match = true;
4417            break;
4418          }
4419        }
4420        if (!match)
4421          return false;
4422      }
4423      return true;
4424    }
4425    // Both the right and left sides have qualifiers.
4426    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
4427         E = lhsOPT->qual_end(); I != E; ++I) {
4428      ObjCProtocolDecl *lhsProto = *I;
4429      bool match = false;
4430
4431      // when comparing an id<P> on lhs with a static type on rhs,
4432      // see if static class implements all of id's protocols, directly or
4433      // through its super class and categories.
4434      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4435           E = rhsQID->qual_end(); J != E; ++J) {
4436        ObjCProtocolDecl *rhsProto = *J;
4437        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4438            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4439          match = true;
4440          break;
4441        }
4442      }
4443      if (!match)
4444        return false;
4445    }
4446    return true;
4447  }
4448  return false;
4449}
4450
4451/// canAssignObjCInterfaces - Return true if the two interface types are
4452/// compatible for assignment from RHS to LHS.  This handles validation of any
4453/// protocol qualifiers on the LHS or RHS.
4454///
4455bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
4456                                         const ObjCObjectPointerType *RHSOPT) {
4457  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4458  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4459
4460  // If either type represents the built-in 'id' or 'Class' types, return true.
4461  if (LHS->isObjCUnqualifiedIdOrClass() ||
4462      RHS->isObjCUnqualifiedIdOrClass())
4463    return true;
4464
4465  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
4466    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4467                                             QualType(RHSOPT,0),
4468                                             false);
4469
4470  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
4471    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
4472                                                QualType(RHSOPT,0));
4473
4474  // If we have 2 user-defined types, fall into that path.
4475  if (LHS->getInterface() && RHS->getInterface())
4476    return canAssignObjCInterfaces(LHS, RHS);
4477
4478  return false;
4479}
4480
4481/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
4482/// for providing type-safty for objective-c pointers used to pass/return
4483/// arguments in block literals. When passed as arguments, passing 'A*' where
4484/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
4485/// not OK. For the return type, the opposite is not OK.
4486bool ASTContext::canAssignObjCInterfacesInBlockPointer(
4487                                         const ObjCObjectPointerType *LHSOPT,
4488                                         const ObjCObjectPointerType *RHSOPT) {
4489  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
4490    return true;
4491
4492  if (LHSOPT->isObjCBuiltinType()) {
4493    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
4494  }
4495
4496  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
4497    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4498                                             QualType(RHSOPT,0),
4499                                             false);
4500
4501  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
4502  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
4503  if (LHS && RHS)  { // We have 2 user-defined types.
4504    if (LHS != RHS) {
4505      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
4506        return false;
4507      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
4508        return true;
4509    }
4510    else
4511      return true;
4512  }
4513  return false;
4514}
4515
4516/// getIntersectionOfProtocols - This routine finds the intersection of set
4517/// of protocols inherited from two distinct objective-c pointer objects.
4518/// It is used to build composite qualifier list of the composite type of
4519/// the conditional expression involving two objective-c pointer objects.
4520static
4521void getIntersectionOfProtocols(ASTContext &Context,
4522                                const ObjCObjectPointerType *LHSOPT,
4523                                const ObjCObjectPointerType *RHSOPT,
4524      llvm::SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
4525
4526  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4527  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4528  assert(LHS->getInterface() && "LHS must have an interface base");
4529  assert(RHS->getInterface() && "RHS must have an interface base");
4530
4531  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
4532  unsigned LHSNumProtocols = LHS->getNumProtocols();
4533  if (LHSNumProtocols > 0)
4534    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
4535  else {
4536    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4537    Context.CollectInheritedProtocols(LHS->getInterface(),
4538                                      LHSInheritedProtocols);
4539    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
4540                                LHSInheritedProtocols.end());
4541  }
4542
4543  unsigned RHSNumProtocols = RHS->getNumProtocols();
4544  if (RHSNumProtocols > 0) {
4545    ObjCProtocolDecl **RHSProtocols =
4546      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
4547    for (unsigned i = 0; i < RHSNumProtocols; ++i)
4548      if (InheritedProtocolSet.count(RHSProtocols[i]))
4549        IntersectionOfProtocols.push_back(RHSProtocols[i]);
4550  }
4551  else {
4552    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
4553    Context.CollectInheritedProtocols(RHS->getInterface(),
4554                                      RHSInheritedProtocols);
4555    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4556         RHSInheritedProtocols.begin(),
4557         E = RHSInheritedProtocols.end(); I != E; ++I)
4558      if (InheritedProtocolSet.count((*I)))
4559        IntersectionOfProtocols.push_back((*I));
4560  }
4561}
4562
4563/// areCommonBaseCompatible - Returns common base class of the two classes if
4564/// one found. Note that this is O'2 algorithm. But it will be called as the
4565/// last type comparison in a ?-exp of ObjC pointer types before a
4566/// warning is issued. So, its invokation is extremely rare.
4567QualType ASTContext::areCommonBaseCompatible(
4568                                          const ObjCObjectPointerType *Lptr,
4569                                          const ObjCObjectPointerType *Rptr) {
4570  const ObjCObjectType *LHS = Lptr->getObjectType();
4571  const ObjCObjectType *RHS = Rptr->getObjectType();
4572  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
4573  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
4574  if (!LDecl || !RDecl)
4575    return QualType();
4576
4577  while ((LDecl = LDecl->getSuperClass())) {
4578    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
4579    if (canAssignObjCInterfaces(LHS, RHS)) {
4580      llvm::SmallVector<ObjCProtocolDecl *, 8> Protocols;
4581      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
4582
4583      QualType Result = QualType(LHS, 0);
4584      if (!Protocols.empty())
4585        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
4586      Result = getObjCObjectPointerType(Result);
4587      return Result;
4588    }
4589  }
4590
4591  return QualType();
4592}
4593
4594bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
4595                                         const ObjCObjectType *RHS) {
4596  assert(LHS->getInterface() && "LHS is not an interface type");
4597  assert(RHS->getInterface() && "RHS is not an interface type");
4598
4599  // Verify that the base decls are compatible: the RHS must be a subclass of
4600  // the LHS.
4601  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
4602    return false;
4603
4604  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
4605  // protocol qualified at all, then we are good.
4606  if (LHS->getNumProtocols() == 0)
4607    return true;
4608
4609  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't, then it
4610  // isn't a superset.
4611  if (RHS->getNumProtocols() == 0)
4612    return true;  // FIXME: should return false!
4613
4614  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
4615                                     LHSPE = LHS->qual_end();
4616       LHSPI != LHSPE; LHSPI++) {
4617    bool RHSImplementsProtocol = false;
4618
4619    // If the RHS doesn't implement the protocol on the left, the types
4620    // are incompatible.
4621    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
4622                                       RHSPE = RHS->qual_end();
4623         RHSPI != RHSPE; RHSPI++) {
4624      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
4625        RHSImplementsProtocol = true;
4626        break;
4627      }
4628    }
4629    // FIXME: For better diagnostics, consider passing back the protocol name.
4630    if (!RHSImplementsProtocol)
4631      return false;
4632  }
4633  // The RHS implements all protocols listed on the LHS.
4634  return true;
4635}
4636
4637bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
4638  // get the "pointed to" types
4639  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
4640  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
4641
4642  if (!LHSOPT || !RHSOPT)
4643    return false;
4644
4645  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
4646         canAssignObjCInterfaces(RHSOPT, LHSOPT);
4647}
4648
4649bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
4650  return canAssignObjCInterfaces(
4651                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
4652                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
4653}
4654
4655/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
4656/// both shall have the identically qualified version of a compatible type.
4657/// C99 6.2.7p1: Two types have compatible types if their types are the
4658/// same. See 6.7.[2,3,5] for additional rules.
4659bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
4660                                    bool CompareUnqualified) {
4661  if (getLangOptions().CPlusPlus)
4662    return hasSameType(LHS, RHS);
4663
4664  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
4665}
4666
4667bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
4668  return !mergeTypes(LHS, RHS, true).isNull();
4669}
4670
4671/// mergeTransparentUnionType - if T is a transparent union type and a member
4672/// of T is compatible with SubType, return the merged type, else return
4673/// QualType()
4674QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
4675                                               bool OfBlockPointer,
4676                                               bool Unqualified) {
4677  if (const RecordType *UT = T->getAsUnionType()) {
4678    RecordDecl *UD = UT->getDecl();
4679    if (UD->hasAttr<TransparentUnionAttr>()) {
4680      for (RecordDecl::field_iterator it = UD->field_begin(),
4681           itend = UD->field_end(); it != itend; ++it) {
4682        QualType ET = it->getType();
4683        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
4684        if (!MT.isNull())
4685          return MT;
4686      }
4687    }
4688  }
4689
4690  return QualType();
4691}
4692
4693/// mergeFunctionArgumentTypes - merge two types which appear as function
4694/// argument types
4695QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
4696                                                bool OfBlockPointer,
4697                                                bool Unqualified) {
4698  // GNU extension: two types are compatible if they appear as a function
4699  // argument, one of the types is a transparent union type and the other
4700  // type is compatible with a union member
4701  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
4702                                              Unqualified);
4703  if (!lmerge.isNull())
4704    return lmerge;
4705
4706  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
4707                                              Unqualified);
4708  if (!rmerge.isNull())
4709    return rmerge;
4710
4711  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
4712}
4713
4714QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
4715                                        bool OfBlockPointer,
4716                                        bool Unqualified) {
4717  const FunctionType *lbase = lhs->getAs<FunctionType>();
4718  const FunctionType *rbase = rhs->getAs<FunctionType>();
4719  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
4720  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
4721  bool allLTypes = true;
4722  bool allRTypes = true;
4723
4724  // Check return type
4725  QualType retType;
4726  if (OfBlockPointer)
4727    retType = mergeTypes(rbase->getResultType(), lbase->getResultType(), true,
4728                         Unqualified);
4729  else
4730   retType = mergeTypes(lbase->getResultType(), rbase->getResultType(),
4731                        false, Unqualified);
4732  if (retType.isNull()) return QualType();
4733
4734  if (Unqualified)
4735    retType = retType.getUnqualifiedType();
4736
4737  CanQualType LRetType = getCanonicalType(lbase->getResultType());
4738  CanQualType RRetType = getCanonicalType(rbase->getResultType());
4739  if (Unqualified) {
4740    LRetType = LRetType.getUnqualifiedType();
4741    RRetType = RRetType.getUnqualifiedType();
4742  }
4743
4744  if (getCanonicalType(retType) != LRetType)
4745    allLTypes = false;
4746  if (getCanonicalType(retType) != RRetType)
4747    allRTypes = false;
4748  // FIXME: double check this
4749  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
4750  //                           rbase->getRegParmAttr() != 0 &&
4751  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
4752  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
4753  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
4754  unsigned RegParm = lbaseInfo.getRegParm() == 0 ? rbaseInfo.getRegParm() :
4755      lbaseInfo.getRegParm();
4756  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
4757  if (NoReturn != lbaseInfo.getNoReturn() ||
4758      RegParm != lbaseInfo.getRegParm())
4759    allLTypes = false;
4760  if (NoReturn != rbaseInfo.getNoReturn() ||
4761      RegParm != rbaseInfo.getRegParm())
4762    allRTypes = false;
4763  CallingConv lcc = lbaseInfo.getCC();
4764  CallingConv rcc = rbaseInfo.getCC();
4765  // Compatible functions must have compatible calling conventions
4766  if (!isSameCallConv(lcc, rcc))
4767    return QualType();
4768
4769  if (lproto && rproto) { // two C99 style function prototypes
4770    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
4771           "C++ shouldn't be here");
4772    unsigned lproto_nargs = lproto->getNumArgs();
4773    unsigned rproto_nargs = rproto->getNumArgs();
4774
4775    // Compatible functions must have the same number of arguments
4776    if (lproto_nargs != rproto_nargs)
4777      return QualType();
4778
4779    // Variadic and non-variadic functions aren't compatible
4780    if (lproto->isVariadic() != rproto->isVariadic())
4781      return QualType();
4782
4783    if (lproto->getTypeQuals() != rproto->getTypeQuals())
4784      return QualType();
4785
4786    // Check argument compatibility
4787    llvm::SmallVector<QualType, 10> types;
4788    for (unsigned i = 0; i < lproto_nargs; i++) {
4789      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
4790      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
4791      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
4792                                                    OfBlockPointer,
4793                                                    Unqualified);
4794      if (argtype.isNull()) return QualType();
4795
4796      if (Unqualified)
4797        argtype = argtype.getUnqualifiedType();
4798
4799      types.push_back(argtype);
4800      if (Unqualified) {
4801        largtype = largtype.getUnqualifiedType();
4802        rargtype = rargtype.getUnqualifiedType();
4803      }
4804
4805      if (getCanonicalType(argtype) != getCanonicalType(largtype))
4806        allLTypes = false;
4807      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
4808        allRTypes = false;
4809    }
4810    if (allLTypes) return lhs;
4811    if (allRTypes) return rhs;
4812    return getFunctionType(retType, types.begin(), types.size(),
4813                           lproto->isVariadic(), lproto->getTypeQuals(),
4814                           false, false, 0, 0,
4815                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4816  }
4817
4818  if (lproto) allRTypes = false;
4819  if (rproto) allLTypes = false;
4820
4821  const FunctionProtoType *proto = lproto ? lproto : rproto;
4822  if (proto) {
4823    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
4824    if (proto->isVariadic()) return QualType();
4825    // Check that the types are compatible with the types that
4826    // would result from default argument promotions (C99 6.7.5.3p15).
4827    // The only types actually affected are promotable integer
4828    // types and floats, which would be passed as a different
4829    // type depending on whether the prototype is visible.
4830    unsigned proto_nargs = proto->getNumArgs();
4831    for (unsigned i = 0; i < proto_nargs; ++i) {
4832      QualType argTy = proto->getArgType(i);
4833
4834      // Look at the promotion type of enum types, since that is the type used
4835      // to pass enum values.
4836      if (const EnumType *Enum = argTy->getAs<EnumType>())
4837        argTy = Enum->getDecl()->getPromotionType();
4838
4839      if (argTy->isPromotableIntegerType() ||
4840          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
4841        return QualType();
4842    }
4843
4844    if (allLTypes) return lhs;
4845    if (allRTypes) return rhs;
4846    return getFunctionType(retType, proto->arg_type_begin(),
4847                           proto->getNumArgs(), proto->isVariadic(),
4848                           proto->getTypeQuals(),
4849                           false, false, 0, 0,
4850                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4851  }
4852
4853  if (allLTypes) return lhs;
4854  if (allRTypes) return rhs;
4855  FunctionType::ExtInfo Info(NoReturn, RegParm, lcc);
4856  return getFunctionNoProtoType(retType, Info);
4857}
4858
4859QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
4860                                bool OfBlockPointer,
4861                                bool Unqualified) {
4862  // C++ [expr]: If an expression initially has the type "reference to T", the
4863  // type is adjusted to "T" prior to any further analysis, the expression
4864  // designates the object or function denoted by the reference, and the
4865  // expression is an lvalue unless the reference is an rvalue reference and
4866  // the expression is a function call (possibly inside parentheses).
4867  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
4868  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
4869
4870  if (Unqualified) {
4871    LHS = LHS.getUnqualifiedType();
4872    RHS = RHS.getUnqualifiedType();
4873  }
4874
4875  QualType LHSCan = getCanonicalType(LHS),
4876           RHSCan = getCanonicalType(RHS);
4877
4878  // If two types are identical, they are compatible.
4879  if (LHSCan == RHSCan)
4880    return LHS;
4881
4882  // If the qualifiers are different, the types aren't compatible... mostly.
4883  Qualifiers LQuals = LHSCan.getLocalQualifiers();
4884  Qualifiers RQuals = RHSCan.getLocalQualifiers();
4885  if (LQuals != RQuals) {
4886    // If any of these qualifiers are different, we have a type
4887    // mismatch.
4888    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
4889        LQuals.getAddressSpace() != RQuals.getAddressSpace())
4890      return QualType();
4891
4892    // Exactly one GC qualifier difference is allowed: __strong is
4893    // okay if the other type has no GC qualifier but is an Objective
4894    // C object pointer (i.e. implicitly strong by default).  We fix
4895    // this by pretending that the unqualified type was actually
4896    // qualified __strong.
4897    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
4898    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
4899    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
4900
4901    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
4902      return QualType();
4903
4904    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
4905      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
4906    }
4907    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
4908      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
4909    }
4910    return QualType();
4911  }
4912
4913  // Okay, qualifiers are equal.
4914
4915  Type::TypeClass LHSClass = LHSCan->getTypeClass();
4916  Type::TypeClass RHSClass = RHSCan->getTypeClass();
4917
4918  // We want to consider the two function types to be the same for these
4919  // comparisons, just force one to the other.
4920  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
4921  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
4922
4923  // Same as above for arrays
4924  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
4925    LHSClass = Type::ConstantArray;
4926  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
4927    RHSClass = Type::ConstantArray;
4928
4929  // ObjCInterfaces are just specialized ObjCObjects.
4930  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
4931  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
4932
4933  // Canonicalize ExtVector -> Vector.
4934  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
4935  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
4936
4937  // If the canonical type classes don't match.
4938  if (LHSClass != RHSClass) {
4939    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
4940    // a signed integer type, or an unsigned integer type.
4941    // Compatibility is based on the underlying type, not the promotion
4942    // type.
4943    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
4944      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
4945        return RHS;
4946    }
4947    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
4948      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
4949        return LHS;
4950    }
4951
4952    return QualType();
4953  }
4954
4955  // The canonical type classes match.
4956  switch (LHSClass) {
4957#define TYPE(Class, Base)
4958#define ABSTRACT_TYPE(Class, Base)
4959#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
4960#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
4961#define DEPENDENT_TYPE(Class, Base) case Type::Class:
4962#include "clang/AST/TypeNodes.def"
4963    assert(false && "Non-canonical and dependent types shouldn't get here");
4964    return QualType();
4965
4966  case Type::LValueReference:
4967  case Type::RValueReference:
4968  case Type::MemberPointer:
4969    assert(false && "C++ should never be in mergeTypes");
4970    return QualType();
4971
4972  case Type::ObjCInterface:
4973  case Type::IncompleteArray:
4974  case Type::VariableArray:
4975  case Type::FunctionProto:
4976  case Type::ExtVector:
4977    assert(false && "Types are eliminated above");
4978    return QualType();
4979
4980  case Type::Pointer:
4981  {
4982    // Merge two pointer types, while trying to preserve typedef info
4983    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
4984    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
4985    if (Unqualified) {
4986      LHSPointee = LHSPointee.getUnqualifiedType();
4987      RHSPointee = RHSPointee.getUnqualifiedType();
4988    }
4989    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
4990                                     Unqualified);
4991    if (ResultType.isNull()) return QualType();
4992    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
4993      return LHS;
4994    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
4995      return RHS;
4996    return getPointerType(ResultType);
4997  }
4998  case Type::BlockPointer:
4999  {
5000    // Merge two block pointer types, while trying to preserve typedef info
5001    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
5002    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
5003    if (Unqualified) {
5004      LHSPointee = LHSPointee.getUnqualifiedType();
5005      RHSPointee = RHSPointee.getUnqualifiedType();
5006    }
5007    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
5008                                     Unqualified);
5009    if (ResultType.isNull()) return QualType();
5010    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5011      return LHS;
5012    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5013      return RHS;
5014    return getBlockPointerType(ResultType);
5015  }
5016  case Type::ConstantArray:
5017  {
5018    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
5019    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
5020    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
5021      return QualType();
5022
5023    QualType LHSElem = getAsArrayType(LHS)->getElementType();
5024    QualType RHSElem = getAsArrayType(RHS)->getElementType();
5025    if (Unqualified) {
5026      LHSElem = LHSElem.getUnqualifiedType();
5027      RHSElem = RHSElem.getUnqualifiedType();
5028    }
5029
5030    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
5031    if (ResultType.isNull()) return QualType();
5032    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5033      return LHS;
5034    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5035      return RHS;
5036    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
5037                                          ArrayType::ArraySizeModifier(), 0);
5038    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
5039                                          ArrayType::ArraySizeModifier(), 0);
5040    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
5041    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
5042    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5043      return LHS;
5044    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5045      return RHS;
5046    if (LVAT) {
5047      // FIXME: This isn't correct! But tricky to implement because
5048      // the array's size has to be the size of LHS, but the type
5049      // has to be different.
5050      return LHS;
5051    }
5052    if (RVAT) {
5053      // FIXME: This isn't correct! But tricky to implement because
5054      // the array's size has to be the size of RHS, but the type
5055      // has to be different.
5056      return RHS;
5057    }
5058    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
5059    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
5060    return getIncompleteArrayType(ResultType,
5061                                  ArrayType::ArraySizeModifier(), 0);
5062  }
5063  case Type::FunctionNoProto:
5064    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
5065  case Type::Record:
5066  case Type::Enum:
5067    return QualType();
5068  case Type::Builtin:
5069    // Only exactly equal builtin types are compatible, which is tested above.
5070    return QualType();
5071  case Type::Complex:
5072    // Distinct complex types are incompatible.
5073    return QualType();
5074  case Type::Vector:
5075    // FIXME: The merged type should be an ExtVector!
5076    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
5077                             RHSCan->getAs<VectorType>()))
5078      return LHS;
5079    return QualType();
5080  case Type::ObjCObject: {
5081    // Check if the types are assignment compatible.
5082    // FIXME: This should be type compatibility, e.g. whether
5083    // "LHS x; RHS x;" at global scope is legal.
5084    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
5085    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
5086    if (canAssignObjCInterfaces(LHSIface, RHSIface))
5087      return LHS;
5088
5089    return QualType();
5090  }
5091  case Type::ObjCObjectPointer: {
5092    if (OfBlockPointer) {
5093      if (canAssignObjCInterfacesInBlockPointer(
5094                                          LHS->getAs<ObjCObjectPointerType>(),
5095                                          RHS->getAs<ObjCObjectPointerType>()))
5096      return LHS;
5097      return QualType();
5098    }
5099    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
5100                                RHS->getAs<ObjCObjectPointerType>()))
5101      return LHS;
5102
5103    return QualType();
5104    }
5105  }
5106
5107  return QualType();
5108}
5109
5110/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
5111/// 'RHS' attributes and returns the merged version; including for function
5112/// return types.
5113QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
5114  QualType LHSCan = getCanonicalType(LHS),
5115  RHSCan = getCanonicalType(RHS);
5116  // If two types are identical, they are compatible.
5117  if (LHSCan == RHSCan)
5118    return LHS;
5119  if (RHSCan->isFunctionType()) {
5120    if (!LHSCan->isFunctionType())
5121      return QualType();
5122    QualType OldReturnType =
5123      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
5124    QualType NewReturnType =
5125      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
5126    QualType ResReturnType =
5127      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
5128    if (ResReturnType.isNull())
5129      return QualType();
5130    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
5131      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
5132      // In either case, use OldReturnType to build the new function type.
5133      const FunctionType *F = LHS->getAs<FunctionType>();
5134      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
5135        FunctionType::ExtInfo Info = getFunctionExtInfo(LHS);
5136        QualType ResultType
5137          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
5138                                  FPT->getNumArgs(), FPT->isVariadic(),
5139                                  FPT->getTypeQuals(),
5140                                  FPT->hasExceptionSpec(),
5141                                  FPT->hasAnyExceptionSpec(),
5142                                  FPT->getNumExceptions(),
5143                                  FPT->exception_begin(),
5144                                  Info);
5145        return ResultType;
5146      }
5147    }
5148    return QualType();
5149  }
5150
5151  // If the qualifiers are different, the types can still be merged.
5152  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5153  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5154  if (LQuals != RQuals) {
5155    // If any of these qualifiers are different, we have a type mismatch.
5156    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5157        LQuals.getAddressSpace() != RQuals.getAddressSpace())
5158      return QualType();
5159
5160    // Exactly one GC qualifier difference is allowed: __strong is
5161    // okay if the other type has no GC qualifier but is an Objective
5162    // C object pointer (i.e. implicitly strong by default).  We fix
5163    // this by pretending that the unqualified type was actually
5164    // qualified __strong.
5165    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5166    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5167    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5168
5169    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5170      return QualType();
5171
5172    if (GC_L == Qualifiers::Strong)
5173      return LHS;
5174    if (GC_R == Qualifiers::Strong)
5175      return RHS;
5176    return QualType();
5177  }
5178
5179  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
5180    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5181    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5182    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
5183    if (ResQT == LHSBaseQT)
5184      return LHS;
5185    if (ResQT == RHSBaseQT)
5186      return RHS;
5187  }
5188  return QualType();
5189}
5190
5191//===----------------------------------------------------------------------===//
5192//                         Integer Predicates
5193//===----------------------------------------------------------------------===//
5194
5195unsigned ASTContext::getIntWidth(QualType T) {
5196  if (EnumType *ET = dyn_cast<EnumType>(T))
5197    T = ET->getDecl()->getIntegerType();
5198  if (T->isBooleanType())
5199    return 1;
5200  // For builtin types, just use the standard type sizing method
5201  return (unsigned)getTypeSize(T);
5202}
5203
5204QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
5205  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
5206
5207  // Turn <4 x signed int> -> <4 x unsigned int>
5208  if (const VectorType *VTy = T->getAs<VectorType>())
5209    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
5210             VTy->getNumElements(), VTy->getAltiVecSpecific());
5211
5212  // For enums, we return the unsigned version of the base type.
5213  if (const EnumType *ETy = T->getAs<EnumType>())
5214    T = ETy->getDecl()->getIntegerType();
5215
5216  const BuiltinType *BTy = T->getAs<BuiltinType>();
5217  assert(BTy && "Unexpected signed integer type");
5218  switch (BTy->getKind()) {
5219  case BuiltinType::Char_S:
5220  case BuiltinType::SChar:
5221    return UnsignedCharTy;
5222  case BuiltinType::Short:
5223    return UnsignedShortTy;
5224  case BuiltinType::Int:
5225    return UnsignedIntTy;
5226  case BuiltinType::Long:
5227    return UnsignedLongTy;
5228  case BuiltinType::LongLong:
5229    return UnsignedLongLongTy;
5230  case BuiltinType::Int128:
5231    return UnsignedInt128Ty;
5232  default:
5233    assert(0 && "Unexpected signed integer type");
5234    return QualType();
5235  }
5236}
5237
5238ExternalASTSource::~ExternalASTSource() { }
5239
5240void ExternalASTSource::PrintStats() { }
5241
5242ASTMutationListener::~ASTMutationListener() { }
5243
5244
5245//===----------------------------------------------------------------------===//
5246//                          Builtin Type Computation
5247//===----------------------------------------------------------------------===//
5248
5249/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
5250/// pointer over the consumed characters.  This returns the resultant type.  If
5251/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
5252/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
5253/// a vector of "i*".
5254///
5255/// RequiresICE is filled in on return to indicate whether the value is required
5256/// to be an Integer Constant Expression.
5257static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
5258                                  ASTContext::GetBuiltinTypeError &Error,
5259                                  bool &RequiresICE,
5260                                  bool AllowTypeModifiers) {
5261  // Modifiers.
5262  int HowLong = 0;
5263  bool Signed = false, Unsigned = false;
5264  RequiresICE = false;
5265
5266  // Read the prefixed modifiers first.
5267  bool Done = false;
5268  while (!Done) {
5269    switch (*Str++) {
5270    default: Done = true; --Str; break;
5271    case 'I':
5272      RequiresICE = true;
5273      break;
5274    case 'S':
5275      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
5276      assert(!Signed && "Can't use 'S' modifier multiple times!");
5277      Signed = true;
5278      break;
5279    case 'U':
5280      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
5281      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
5282      Unsigned = true;
5283      break;
5284    case 'L':
5285      assert(HowLong <= 2 && "Can't have LLLL modifier");
5286      ++HowLong;
5287      break;
5288    }
5289  }
5290
5291  QualType Type;
5292
5293  // Read the base type.
5294  switch (*Str++) {
5295  default: assert(0 && "Unknown builtin type letter!");
5296  case 'v':
5297    assert(HowLong == 0 && !Signed && !Unsigned &&
5298           "Bad modifiers used with 'v'!");
5299    Type = Context.VoidTy;
5300    break;
5301  case 'f':
5302    assert(HowLong == 0 && !Signed && !Unsigned &&
5303           "Bad modifiers used with 'f'!");
5304    Type = Context.FloatTy;
5305    break;
5306  case 'd':
5307    assert(HowLong < 2 && !Signed && !Unsigned &&
5308           "Bad modifiers used with 'd'!");
5309    if (HowLong)
5310      Type = Context.LongDoubleTy;
5311    else
5312      Type = Context.DoubleTy;
5313    break;
5314  case 's':
5315    assert(HowLong == 0 && "Bad modifiers used with 's'!");
5316    if (Unsigned)
5317      Type = Context.UnsignedShortTy;
5318    else
5319      Type = Context.ShortTy;
5320    break;
5321  case 'i':
5322    if (HowLong == 3)
5323      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
5324    else if (HowLong == 2)
5325      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
5326    else if (HowLong == 1)
5327      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
5328    else
5329      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
5330    break;
5331  case 'c':
5332    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
5333    if (Signed)
5334      Type = Context.SignedCharTy;
5335    else if (Unsigned)
5336      Type = Context.UnsignedCharTy;
5337    else
5338      Type = Context.CharTy;
5339    break;
5340  case 'b': // boolean
5341    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
5342    Type = Context.BoolTy;
5343    break;
5344  case 'z':  // size_t.
5345    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
5346    Type = Context.getSizeType();
5347    break;
5348  case 'F':
5349    Type = Context.getCFConstantStringType();
5350    break;
5351  case 'a':
5352    Type = Context.getBuiltinVaListType();
5353    assert(!Type.isNull() && "builtin va list type not initialized!");
5354    break;
5355  case 'A':
5356    // This is a "reference" to a va_list; however, what exactly
5357    // this means depends on how va_list is defined. There are two
5358    // different kinds of va_list: ones passed by value, and ones
5359    // passed by reference.  An example of a by-value va_list is
5360    // x86, where va_list is a char*. An example of by-ref va_list
5361    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
5362    // we want this argument to be a char*&; for x86-64, we want
5363    // it to be a __va_list_tag*.
5364    Type = Context.getBuiltinVaListType();
5365    assert(!Type.isNull() && "builtin va list type not initialized!");
5366    if (Type->isArrayType())
5367      Type = Context.getArrayDecayedType(Type);
5368    else
5369      Type = Context.getLValueReferenceType(Type);
5370    break;
5371  case 'V': {
5372    char *End;
5373    unsigned NumElements = strtoul(Str, &End, 10);
5374    assert(End != Str && "Missing vector size");
5375    Str = End;
5376
5377    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
5378                                             RequiresICE, false);
5379    assert(!RequiresICE && "Can't require vector ICE");
5380
5381    // TODO: No way to make AltiVec vectors in builtins yet.
5382    Type = Context.getVectorType(ElementType, NumElements,
5383                                 VectorType::NotAltiVec);
5384    break;
5385  }
5386  case 'X': {
5387    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
5388                                             false);
5389    assert(!RequiresICE && "Can't require complex ICE");
5390    Type = Context.getComplexType(ElementType);
5391    break;
5392  }
5393  case 'P':
5394    Type = Context.getFILEType();
5395    if (Type.isNull()) {
5396      Error = ASTContext::GE_Missing_stdio;
5397      return QualType();
5398    }
5399    break;
5400  case 'J':
5401    if (Signed)
5402      Type = Context.getsigjmp_bufType();
5403    else
5404      Type = Context.getjmp_bufType();
5405
5406    if (Type.isNull()) {
5407      Error = ASTContext::GE_Missing_setjmp;
5408      return QualType();
5409    }
5410    break;
5411  }
5412
5413  // If there are modifiers and if we're allowed to parse them, go for it.
5414  Done = !AllowTypeModifiers;
5415  while (!Done) {
5416    switch (char c = *Str++) {
5417    default: Done = true; --Str; break;
5418    case '*':
5419    case '&': {
5420      // Both pointers and references can have their pointee types
5421      // qualified with an address space.
5422      char *End;
5423      unsigned AddrSpace = strtoul(Str, &End, 10);
5424      if (End != Str && AddrSpace != 0) {
5425        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
5426        Str = End;
5427      }
5428      if (c == '*')
5429        Type = Context.getPointerType(Type);
5430      else
5431        Type = Context.getLValueReferenceType(Type);
5432      break;
5433    }
5434    // FIXME: There's no way to have a built-in with an rvalue ref arg.
5435    case 'C':
5436      Type = Type.withConst();
5437      break;
5438    case 'D':
5439      Type = Context.getVolatileType(Type);
5440      break;
5441    }
5442  }
5443
5444  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
5445         "Integer constant 'I' type must be an integer");
5446
5447  return Type;
5448}
5449
5450/// GetBuiltinType - Return the type for the specified builtin.
5451QualType ASTContext::GetBuiltinType(unsigned Id,
5452                                    GetBuiltinTypeError &Error,
5453                                    unsigned *IntegerConstantArgs) {
5454  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
5455
5456  llvm::SmallVector<QualType, 8> ArgTypes;
5457
5458  bool RequiresICE = false;
5459  Error = GE_None;
5460  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
5461                                       RequiresICE, true);
5462  if (Error != GE_None)
5463    return QualType();
5464
5465  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
5466
5467  while (TypeStr[0] && TypeStr[0] != '.') {
5468    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
5469    if (Error != GE_None)
5470      return QualType();
5471
5472    // If this argument is required to be an IntegerConstantExpression and the
5473    // caller cares, fill in the bitmask we return.
5474    if (RequiresICE && IntegerConstantArgs)
5475      *IntegerConstantArgs |= 1 << ArgTypes.size();
5476
5477    // Do array -> pointer decay.  The builtin should use the decayed type.
5478    if (Ty->isArrayType())
5479      Ty = getArrayDecayedType(Ty);
5480
5481    ArgTypes.push_back(Ty);
5482  }
5483
5484  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
5485         "'.' should only occur at end of builtin type list!");
5486
5487  // handle untyped/variadic arguments "T c99Style();" or "T cppStyle(...);".
5488  if (ArgTypes.size() == 0 && TypeStr[0] == '.')
5489    return getFunctionNoProtoType(ResType);
5490
5491  // FIXME: Should we create noreturn types?
5492  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(),
5493                         TypeStr[0] == '.', 0, false, false, 0, 0,
5494                         FunctionType::ExtInfo());
5495}
5496
5497QualType
5498ASTContext::UsualArithmeticConversionsType(QualType lhs, QualType rhs) {
5499  // Perform the usual unary conversions. We do this early so that
5500  // integral promotions to "int" can allow us to exit early, in the
5501  // lhs == rhs check. Also, for conversion purposes, we ignore any
5502  // qualifiers.  For example, "const float" and "float" are
5503  // equivalent.
5504  if (lhs->isPromotableIntegerType())
5505    lhs = getPromotedIntegerType(lhs);
5506  else
5507    lhs = lhs.getUnqualifiedType();
5508  if (rhs->isPromotableIntegerType())
5509    rhs = getPromotedIntegerType(rhs);
5510  else
5511    rhs = rhs.getUnqualifiedType();
5512
5513  // If both types are identical, no conversion is needed.
5514  if (lhs == rhs)
5515    return lhs;
5516
5517  // If either side is a non-arithmetic type (e.g. a pointer), we are done.
5518  // The caller can deal with this (e.g. pointer + int).
5519  if (!lhs->isArithmeticType() || !rhs->isArithmeticType())
5520    return lhs;
5521
5522  // At this point, we have two different arithmetic types.
5523
5524  // Handle complex types first (C99 6.3.1.8p1).
5525  if (lhs->isComplexType() || rhs->isComplexType()) {
5526    // if we have an integer operand, the result is the complex type.
5527    if (rhs->isIntegerType() || rhs->isComplexIntegerType()) {
5528      // convert the rhs to the lhs complex type.
5529      return lhs;
5530    }
5531    if (lhs->isIntegerType() || lhs->isComplexIntegerType()) {
5532      // convert the lhs to the rhs complex type.
5533      return rhs;
5534    }
5535    // This handles complex/complex, complex/float, or float/complex.
5536    // When both operands are complex, the shorter operand is converted to the
5537    // type of the longer, and that is the type of the result. This corresponds
5538    // to what is done when combining two real floating-point operands.
5539    // The fun begins when size promotion occur across type domains.
5540    // From H&S 6.3.4: When one operand is complex and the other is a real
5541    // floating-point type, the less precise type is converted, within it's
5542    // real or complex domain, to the precision of the other type. For example,
5543    // when combining a "long double" with a "double _Complex", the
5544    // "double _Complex" is promoted to "long double _Complex".
5545    int result = getFloatingTypeOrder(lhs, rhs);
5546
5547    if (result > 0) { // The left side is bigger, convert rhs.
5548      rhs = getFloatingTypeOfSizeWithinDomain(lhs, rhs);
5549    } else if (result < 0) { // The right side is bigger, convert lhs.
5550      lhs = getFloatingTypeOfSizeWithinDomain(rhs, lhs);
5551    }
5552    // At this point, lhs and rhs have the same rank/size. Now, make sure the
5553    // domains match. This is a requirement for our implementation, C99
5554    // does not require this promotion.
5555    if (lhs != rhs) { // Domains don't match, we have complex/float mix.
5556      if (lhs->isRealFloatingType()) { // handle "double, _Complex double".
5557        return rhs;
5558      } else { // handle "_Complex double, double".
5559        return lhs;
5560      }
5561    }
5562    return lhs; // The domain/size match exactly.
5563  }
5564  // Now handle "real" floating types (i.e. float, double, long double).
5565  if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) {
5566    // if we have an integer operand, the result is the real floating type.
5567    if (rhs->isIntegerType()) {
5568      // convert rhs to the lhs floating point type.
5569      return lhs;
5570    }
5571    if (rhs->isComplexIntegerType()) {
5572      // convert rhs to the complex floating point type.
5573      return getComplexType(lhs);
5574    }
5575    if (lhs->isIntegerType()) {
5576      // convert lhs to the rhs floating point type.
5577      return rhs;
5578    }
5579    if (lhs->isComplexIntegerType()) {
5580      // convert lhs to the complex floating point type.
5581      return getComplexType(rhs);
5582    }
5583    // We have two real floating types, float/complex combos were handled above.
5584    // Convert the smaller operand to the bigger result.
5585    int result = getFloatingTypeOrder(lhs, rhs);
5586    if (result > 0) // convert the rhs
5587      return lhs;
5588    assert(result < 0 && "illegal float comparison");
5589    return rhs;   // convert the lhs
5590  }
5591  if (lhs->isComplexIntegerType() || rhs->isComplexIntegerType()) {
5592    // Handle GCC complex int extension.
5593    const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType();
5594    const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType();
5595
5596    if (lhsComplexInt && rhsComplexInt) {
5597      if (getIntegerTypeOrder(lhsComplexInt->getElementType(),
5598                              rhsComplexInt->getElementType()) >= 0)
5599        return lhs; // convert the rhs
5600      return rhs;
5601    } else if (lhsComplexInt && rhs->isIntegerType()) {
5602      // convert the rhs to the lhs complex type.
5603      return lhs;
5604    } else if (rhsComplexInt && lhs->isIntegerType()) {
5605      // convert the lhs to the rhs complex type.
5606      return rhs;
5607    }
5608  }
5609  // Finally, we have two differing integer types.
5610  // The rules for this case are in C99 6.3.1.8
5611  int compare = getIntegerTypeOrder(lhs, rhs);
5612  bool lhsSigned = lhs->hasSignedIntegerRepresentation(),
5613       rhsSigned = rhs->hasSignedIntegerRepresentation();
5614  QualType destType;
5615  if (lhsSigned == rhsSigned) {
5616    // Same signedness; use the higher-ranked type
5617    destType = compare >= 0 ? lhs : rhs;
5618  } else if (compare != (lhsSigned ? 1 : -1)) {
5619    // The unsigned type has greater than or equal rank to the
5620    // signed type, so use the unsigned type
5621    destType = lhsSigned ? rhs : lhs;
5622  } else if (getIntWidth(lhs) != getIntWidth(rhs)) {
5623    // The two types are different widths; if we are here, that
5624    // means the signed type is larger than the unsigned type, so
5625    // use the signed type.
5626    destType = lhsSigned ? lhs : rhs;
5627  } else {
5628    // The signed type is higher-ranked than the unsigned type,
5629    // but isn't actually any bigger (like unsigned int and long
5630    // on most 32-bit systems).  Use the unsigned type corresponding
5631    // to the signed type.
5632    destType = getCorrespondingUnsignedType(lhsSigned ? lhs : rhs);
5633  }
5634  return destType;
5635}
5636
5637GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
5638  GVALinkage External = GVA_StrongExternal;
5639
5640  Linkage L = FD->getLinkage();
5641  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5642      FD->getType()->getLinkage() == UniqueExternalLinkage)
5643    L = UniqueExternalLinkage;
5644
5645  switch (L) {
5646  case NoLinkage:
5647  case InternalLinkage:
5648  case UniqueExternalLinkage:
5649    return GVA_Internal;
5650
5651  case ExternalLinkage:
5652    switch (FD->getTemplateSpecializationKind()) {
5653    case TSK_Undeclared:
5654    case TSK_ExplicitSpecialization:
5655      External = GVA_StrongExternal;
5656      break;
5657
5658    case TSK_ExplicitInstantiationDefinition:
5659      return GVA_ExplicitTemplateInstantiation;
5660
5661    case TSK_ExplicitInstantiationDeclaration:
5662    case TSK_ImplicitInstantiation:
5663      External = GVA_TemplateInstantiation;
5664      break;
5665    }
5666  }
5667
5668  if (!FD->isInlined())
5669    return External;
5670
5671  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
5672    // GNU or C99 inline semantics. Determine whether this symbol should be
5673    // externally visible.
5674    if (FD->isInlineDefinitionExternallyVisible())
5675      return External;
5676
5677    // C99 inline semantics, where the symbol is not externally visible.
5678    return GVA_C99Inline;
5679  }
5680
5681  // C++0x [temp.explicit]p9:
5682  //   [ Note: The intent is that an inline function that is the subject of
5683  //   an explicit instantiation declaration will still be implicitly
5684  //   instantiated when used so that the body can be considered for
5685  //   inlining, but that no out-of-line copy of the inline function would be
5686  //   generated in the translation unit. -- end note ]
5687  if (FD->getTemplateSpecializationKind()
5688                                       == TSK_ExplicitInstantiationDeclaration)
5689    return GVA_C99Inline;
5690
5691  return GVA_CXXInline;
5692}
5693
5694GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
5695  // If this is a static data member, compute the kind of template
5696  // specialization. Otherwise, this variable is not part of a
5697  // template.
5698  TemplateSpecializationKind TSK = TSK_Undeclared;
5699  if (VD->isStaticDataMember())
5700    TSK = VD->getTemplateSpecializationKind();
5701
5702  Linkage L = VD->getLinkage();
5703  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5704      VD->getType()->getLinkage() == UniqueExternalLinkage)
5705    L = UniqueExternalLinkage;
5706
5707  switch (L) {
5708  case NoLinkage:
5709  case InternalLinkage:
5710  case UniqueExternalLinkage:
5711    return GVA_Internal;
5712
5713  case ExternalLinkage:
5714    switch (TSK) {
5715    case TSK_Undeclared:
5716    case TSK_ExplicitSpecialization:
5717      return GVA_StrongExternal;
5718
5719    case TSK_ExplicitInstantiationDeclaration:
5720      llvm_unreachable("Variable should not be instantiated");
5721      // Fall through to treat this like any other instantiation.
5722
5723    case TSK_ExplicitInstantiationDefinition:
5724      return GVA_ExplicitTemplateInstantiation;
5725
5726    case TSK_ImplicitInstantiation:
5727      return GVA_TemplateInstantiation;
5728    }
5729  }
5730
5731  return GVA_StrongExternal;
5732}
5733
5734bool ASTContext::DeclMustBeEmitted(const Decl *D) {
5735  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
5736    if (!VD->isFileVarDecl())
5737      return false;
5738  } else if (!isa<FunctionDecl>(D))
5739    return false;
5740
5741  // Weak references don't produce any output by themselves.
5742  if (D->hasAttr<WeakRefAttr>())
5743    return false;
5744
5745  // Aliases and used decls are required.
5746  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
5747    return true;
5748
5749  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
5750    // Forward declarations aren't required.
5751    if (!FD->isThisDeclarationADefinition())
5752      return false;
5753
5754    // Constructors and destructors are required.
5755    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
5756      return true;
5757
5758    // The key function for a class is required.
5759    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
5760      const CXXRecordDecl *RD = MD->getParent();
5761      if (MD->isOutOfLine() && RD->isDynamicClass()) {
5762        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
5763        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
5764          return true;
5765      }
5766    }
5767
5768    GVALinkage Linkage = GetGVALinkageForFunction(FD);
5769
5770    // static, static inline, always_inline, and extern inline functions can
5771    // always be deferred.  Normal inline functions can be deferred in C99/C++.
5772    // Implicit template instantiations can also be deferred in C++.
5773    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
5774        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
5775      return false;
5776    return true;
5777  }
5778
5779  const VarDecl *VD = cast<VarDecl>(D);
5780  assert(VD->isFileVarDecl() && "Expected file scoped var");
5781
5782  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
5783    return false;
5784
5785  // Structs that have non-trivial constructors or destructors are required.
5786
5787  // FIXME: Handle references.
5788  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
5789    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
5790      if (RD->hasDefinition() &&
5791          (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()))
5792        return true;
5793    }
5794  }
5795
5796  GVALinkage L = GetGVALinkageForVariable(VD);
5797  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
5798    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
5799      return false;
5800  }
5801
5802  return true;
5803}
5804
5805CXXABI::~CXXABI() {}
5806