ASTContext.cpp revision 643f84353b3b7bbf9b73bcbc7da0ef8a39a5ca99 
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
2727    // If we have some kind of dependent-named type (e.g., "typename T::type"),
2728    // break it apart into its prefix and identifier, then reconsititute those
2729    // as the canonical nested-name-specifier. This is required to canonicalize
2730    // a dependent nested-name-specifier involving typedefs of dependent-name
2731    // types, e.g.,
2732    //   typedef typename T::type T1;
2733    //   typedef typename T1::type T2;
2734    if (const DependentNameType *DNT = T->getAs<DependentNameType>()) {
2735      NestedNameSpecifier *Prefix
2736        = getCanonicalNestedNameSpecifier(DNT->getQualifier());
2737      return NestedNameSpecifier::Create(*this, Prefix,
2738                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
2739    }
2740
2741    // Do the same thing as above, but with dependent-named specializations.
2742    if (const DependentTemplateSpecializationType *DTST
2743          = T->getAs<DependentTemplateSpecializationType>()) {
2744      NestedNameSpecifier *Prefix
2745        = getCanonicalNestedNameSpecifier(DTST->getQualifier());
2746      TemplateName Name
2747        = getDependentTemplateName(Prefix, DTST->getIdentifier());
2748      T = getTemplateSpecializationType(Name,
2749                                        DTST->getArgs(), DTST->getNumArgs());
2750      T = getCanonicalType(T);
2751    }
2752
2753    return NestedNameSpecifier::Create(*this, 0, false, T.getTypePtr());
2754  }
2755
2756  case NestedNameSpecifier::Global:
2757    // The global specifier is canonical and unique.
2758    return NNS;
2759  }
2760
2761  // Required to silence a GCC warning
2762  return 0;
2763}
2764
2765
2766const ArrayType *ASTContext::getAsArrayType(QualType T) {
2767  // Handle the non-qualified case efficiently.
2768  if (!T.hasLocalQualifiers()) {
2769    // Handle the common positive case fast.
2770    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
2771      return AT;
2772  }
2773
2774  // Handle the common negative case fast.
2775  QualType CType = T->getCanonicalTypeInternal();
2776  if (!isa<ArrayType>(CType))
2777    return 0;
2778
2779  // Apply any qualifiers from the array type to the element type.  This
2780  // implements C99 6.7.3p8: "If the specification of an array type includes
2781  // any type qualifiers, the element type is so qualified, not the array type."
2782
2783  // If we get here, we either have type qualifiers on the type, or we have
2784  // sugar such as a typedef in the way.  If we have type qualifiers on the type
2785  // we must propagate them down into the element type.
2786
2787  QualifierCollector Qs;
2788  const Type *Ty = Qs.strip(T.getDesugaredType());
2789
2790  // If we have a simple case, just return now.
2791  const ArrayType *ATy = dyn_cast<ArrayType>(Ty);
2792  if (ATy == 0 || Qs.empty())
2793    return ATy;
2794
2795  // Otherwise, we have an array and we have qualifiers on it.  Push the
2796  // qualifiers into the array element type and return a new array type.
2797  // Get the canonical version of the element with the extra qualifiers on it.
2798  // This can recursively sink qualifiers through multiple levels of arrays.
2799  QualType NewEltTy = getQualifiedType(ATy->getElementType(), Qs);
2800
2801  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
2802    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
2803                                                CAT->getSizeModifier(),
2804                                           CAT->getIndexTypeCVRQualifiers()));
2805  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
2806    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
2807                                                  IAT->getSizeModifier(),
2808                                           IAT->getIndexTypeCVRQualifiers()));
2809
2810  if (const DependentSizedArrayType *DSAT
2811        = dyn_cast<DependentSizedArrayType>(ATy))
2812    return cast<ArrayType>(
2813                     getDependentSizedArrayType(NewEltTy,
2814                                                DSAT->getSizeExpr(),
2815                                                DSAT->getSizeModifier(),
2816                                              DSAT->getIndexTypeCVRQualifiers(),
2817                                                DSAT->getBracketsRange()));
2818
2819  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
2820  return cast<ArrayType>(getVariableArrayType(NewEltTy,
2821                                              VAT->getSizeExpr(),
2822                                              VAT->getSizeModifier(),
2823                                              VAT->getIndexTypeCVRQualifiers(),
2824                                              VAT->getBracketsRange()));
2825}
2826
2827/// getArrayDecayedType - Return the properly qualified result of decaying the
2828/// specified array type to a pointer.  This operation is non-trivial when
2829/// handling typedefs etc.  The canonical type of "T" must be an array type,
2830/// this returns a pointer to a properly qualified element of the array.
2831///
2832/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
2833QualType ASTContext::getArrayDecayedType(QualType Ty) {
2834  // Get the element type with 'getAsArrayType' so that we don't lose any
2835  // typedefs in the element type of the array.  This also handles propagation
2836  // of type qualifiers from the array type into the element type if present
2837  // (C99 6.7.3p8).
2838  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
2839  assert(PrettyArrayType && "Not an array type!");
2840
2841  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
2842
2843  // int x[restrict 4] ->  int *restrict
2844  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
2845}
2846
2847QualType ASTContext::getBaseElementType(QualType QT) {
2848  QualifierCollector Qs;
2849  while (const ArrayType *AT = getAsArrayType(QualType(Qs.strip(QT), 0)))
2850    QT = AT->getElementType();
2851  return Qs.apply(QT);
2852}
2853
2854QualType ASTContext::getBaseElementType(const ArrayType *AT) {
2855  QualType ElemTy = AT->getElementType();
2856
2857  if (const ArrayType *AT = getAsArrayType(ElemTy))
2858    return getBaseElementType(AT);
2859
2860  return ElemTy;
2861}
2862
2863/// getConstantArrayElementCount - Returns number of constant array elements.
2864uint64_t
2865ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
2866  uint64_t ElementCount = 1;
2867  do {
2868    ElementCount *= CA->getSize().getZExtValue();
2869    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
2870  } while (CA);
2871  return ElementCount;
2872}
2873
2874/// getFloatingRank - Return a relative rank for floating point types.
2875/// This routine will assert if passed a built-in type that isn't a float.
2876static FloatingRank getFloatingRank(QualType T) {
2877  if (const ComplexType *CT = T->getAs<ComplexType>())
2878    return getFloatingRank(CT->getElementType());
2879
2880  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
2881  switch (T->getAs<BuiltinType>()->getKind()) {
2882  default: assert(0 && "getFloatingRank(): not a floating type");
2883  case BuiltinType::Float:      return FloatRank;
2884  case BuiltinType::Double:     return DoubleRank;
2885  case BuiltinType::LongDouble: return LongDoubleRank;
2886  }
2887}
2888
2889/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
2890/// point or a complex type (based on typeDomain/typeSize).
2891/// 'typeDomain' is a real floating point or complex type.
2892/// 'typeSize' is a real floating point or complex type.
2893QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
2894                                                       QualType Domain) const {
2895  FloatingRank EltRank = getFloatingRank(Size);
2896  if (Domain->isComplexType()) {
2897    switch (EltRank) {
2898    default: assert(0 && "getFloatingRank(): illegal value for rank");
2899    case FloatRank:      return FloatComplexTy;
2900    case DoubleRank:     return DoubleComplexTy;
2901    case LongDoubleRank: return LongDoubleComplexTy;
2902    }
2903  }
2904
2905  assert(Domain->isRealFloatingType() && "Unknown domain!");
2906  switch (EltRank) {
2907  default: assert(0 && "getFloatingRank(): illegal value for rank");
2908  case FloatRank:      return FloatTy;
2909  case DoubleRank:     return DoubleTy;
2910  case LongDoubleRank: return LongDoubleTy;
2911  }
2912}
2913
2914/// getFloatingTypeOrder - Compare the rank of the two specified floating
2915/// point types, ignoring the domain of the type (i.e. 'double' ==
2916/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2917/// LHS < RHS, return -1.
2918int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) {
2919  FloatingRank LHSR = getFloatingRank(LHS);
2920  FloatingRank RHSR = getFloatingRank(RHS);
2921
2922  if (LHSR == RHSR)
2923    return 0;
2924  if (LHSR > RHSR)
2925    return 1;
2926  return -1;
2927}
2928
2929/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
2930/// routine will assert if passed a built-in type that isn't an integer or enum,
2931/// or if it is not canonicalized.
2932unsigned ASTContext::getIntegerRank(Type *T) {
2933  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
2934  if (EnumType* ET = dyn_cast<EnumType>(T))
2935    T = ET->getDecl()->getPromotionType().getTypePtr();
2936
2937  if (T->isSpecificBuiltinType(BuiltinType::WChar))
2938    T = getFromTargetType(Target.getWCharType()).getTypePtr();
2939
2940  if (T->isSpecificBuiltinType(BuiltinType::Char16))
2941    T = getFromTargetType(Target.getChar16Type()).getTypePtr();
2942
2943  if (T->isSpecificBuiltinType(BuiltinType::Char32))
2944    T = getFromTargetType(Target.getChar32Type()).getTypePtr();
2945
2946  switch (cast<BuiltinType>(T)->getKind()) {
2947  default: assert(0 && "getIntegerRank(): not a built-in integer");
2948  case BuiltinType::Bool:
2949    return 1 + (getIntWidth(BoolTy) << 3);
2950  case BuiltinType::Char_S:
2951  case BuiltinType::Char_U:
2952  case BuiltinType::SChar:
2953  case BuiltinType::UChar:
2954    return 2 + (getIntWidth(CharTy) << 3);
2955  case BuiltinType::Short:
2956  case BuiltinType::UShort:
2957    return 3 + (getIntWidth(ShortTy) << 3);
2958  case BuiltinType::Int:
2959  case BuiltinType::UInt:
2960    return 4 + (getIntWidth(IntTy) << 3);
2961  case BuiltinType::Long:
2962  case BuiltinType::ULong:
2963    return 5 + (getIntWidth(LongTy) << 3);
2964  case BuiltinType::LongLong:
2965  case BuiltinType::ULongLong:
2966    return 6 + (getIntWidth(LongLongTy) << 3);
2967  case BuiltinType::Int128:
2968  case BuiltinType::UInt128:
2969    return 7 + (getIntWidth(Int128Ty) << 3);
2970  }
2971}
2972
2973/// \brief Whether this is a promotable bitfield reference according
2974/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
2975///
2976/// \returns the type this bit-field will promote to, or NULL if no
2977/// promotion occurs.
2978QualType ASTContext::isPromotableBitField(Expr *E) {
2979  if (E->isTypeDependent() || E->isValueDependent())
2980    return QualType();
2981
2982  FieldDecl *Field = E->getBitField();
2983  if (!Field)
2984    return QualType();
2985
2986  QualType FT = Field->getType();
2987
2988  llvm::APSInt BitWidthAP = Field->getBitWidth()->EvaluateAsInt(*this);
2989  uint64_t BitWidth = BitWidthAP.getZExtValue();
2990  uint64_t IntSize = getTypeSize(IntTy);
2991  // GCC extension compatibility: if the bit-field size is less than or equal
2992  // to the size of int, it gets promoted no matter what its type is.
2993  // For instance, unsigned long bf : 4 gets promoted to signed int.
2994  if (BitWidth < IntSize)
2995    return IntTy;
2996
2997  if (BitWidth == IntSize)
2998    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
2999
3000  // Types bigger than int are not subject to promotions, and therefore act
3001  // like the base type.
3002  // FIXME: This doesn't quite match what gcc does, but what gcc does here
3003  // is ridiculous.
3004  return QualType();
3005}
3006
3007/// getPromotedIntegerType - Returns the type that Promotable will
3008/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
3009/// integer type.
3010QualType ASTContext::getPromotedIntegerType(QualType Promotable) {
3011  assert(!Promotable.isNull());
3012  assert(Promotable->isPromotableIntegerType());
3013  if (const EnumType *ET = Promotable->getAs<EnumType>())
3014    return ET->getDecl()->getPromotionType();
3015  if (Promotable->isSignedIntegerType())
3016    return IntTy;
3017  uint64_t PromotableSize = getTypeSize(Promotable);
3018  uint64_t IntSize = getTypeSize(IntTy);
3019  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3020  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3021}
3022
3023/// getIntegerTypeOrder - Returns the highest ranked integer type:
3024/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3025/// LHS < RHS, return -1.
3026int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) {
3027  Type *LHSC = getCanonicalType(LHS).getTypePtr();
3028  Type *RHSC = getCanonicalType(RHS).getTypePtr();
3029  if (LHSC == RHSC) return 0;
3030
3031  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3032  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3033
3034  unsigned LHSRank = getIntegerRank(LHSC);
3035  unsigned RHSRank = getIntegerRank(RHSC);
3036
3037  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3038    if (LHSRank == RHSRank) return 0;
3039    return LHSRank > RHSRank ? 1 : -1;
3040  }
3041
3042  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3043  if (LHSUnsigned) {
3044    // If the unsigned [LHS] type is larger, return it.
3045    if (LHSRank >= RHSRank)
3046      return 1;
3047
3048    // If the signed type can represent all values of the unsigned type, it
3049    // wins.  Because we are dealing with 2's complement and types that are
3050    // powers of two larger than each other, this is always safe.
3051    return -1;
3052  }
3053
3054  // If the unsigned [RHS] type is larger, return it.
3055  if (RHSRank >= LHSRank)
3056    return -1;
3057
3058  // If the signed type can represent all values of the unsigned type, it
3059  // wins.  Because we are dealing with 2's complement and types that are
3060  // powers of two larger than each other, this is always safe.
3061  return 1;
3062}
3063
3064static RecordDecl *
3065CreateRecordDecl(ASTContext &Ctx, RecordDecl::TagKind TK, DeclContext *DC,
3066                 SourceLocation L, IdentifierInfo *Id) {
3067  if (Ctx.getLangOptions().CPlusPlus)
3068    return CXXRecordDecl::Create(Ctx, TK, DC, L, Id);
3069  else
3070    return RecordDecl::Create(Ctx, TK, DC, L, Id);
3071}
3072
3073// getCFConstantStringType - Return the type used for constant CFStrings.
3074QualType ASTContext::getCFConstantStringType() {
3075  if (!CFConstantStringTypeDecl) {
3076    CFConstantStringTypeDecl =
3077      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3078                       &Idents.get("NSConstantString"));
3079    CFConstantStringTypeDecl->startDefinition();
3080
3081    QualType FieldTypes[4];
3082
3083    // const int *isa;
3084    FieldTypes[0] = getPointerType(IntTy.withConst());
3085    // int flags;
3086    FieldTypes[1] = IntTy;
3087    // const char *str;
3088    FieldTypes[2] = getPointerType(CharTy.withConst());
3089    // long length;
3090    FieldTypes[3] = LongTy;
3091
3092    // Create fields
3093    for (unsigned i = 0; i < 4; ++i) {
3094      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3095                                           SourceLocation(), 0,
3096                                           FieldTypes[i], /*TInfo=*/0,
3097                                           /*BitWidth=*/0,
3098                                           /*Mutable=*/false);
3099      Field->setAccess(AS_public);
3100      CFConstantStringTypeDecl->addDecl(Field);
3101    }
3102
3103    CFConstantStringTypeDecl->completeDefinition();
3104  }
3105
3106  return getTagDeclType(CFConstantStringTypeDecl);
3107}
3108
3109void ASTContext::setCFConstantStringType(QualType T) {
3110  const RecordType *Rec = T->getAs<RecordType>();
3111  assert(Rec && "Invalid CFConstantStringType");
3112  CFConstantStringTypeDecl = Rec->getDecl();
3113}
3114
3115// getNSConstantStringType - Return the type used for constant NSStrings.
3116QualType ASTContext::getNSConstantStringType() {
3117  if (!NSConstantStringTypeDecl) {
3118    NSConstantStringTypeDecl =
3119    CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3120                     &Idents.get("__builtin_NSString"));
3121    NSConstantStringTypeDecl->startDefinition();
3122
3123    QualType FieldTypes[3];
3124
3125    // const int *isa;
3126    FieldTypes[0] = getPointerType(IntTy.withConst());
3127    // const char *str;
3128    FieldTypes[1] = getPointerType(CharTy.withConst());
3129    // unsigned int length;
3130    FieldTypes[2] = UnsignedIntTy;
3131
3132    // Create fields
3133    for (unsigned i = 0; i < 3; ++i) {
3134      FieldDecl *Field = FieldDecl::Create(*this, NSConstantStringTypeDecl,
3135                                           SourceLocation(), 0,
3136                                           FieldTypes[i], /*TInfo=*/0,
3137                                           /*BitWidth=*/0,
3138                                           /*Mutable=*/false);
3139      Field->setAccess(AS_public);
3140      NSConstantStringTypeDecl->addDecl(Field);
3141    }
3142
3143    NSConstantStringTypeDecl->completeDefinition();
3144  }
3145
3146  return getTagDeclType(NSConstantStringTypeDecl);
3147}
3148
3149void ASTContext::setNSConstantStringType(QualType T) {
3150  const RecordType *Rec = T->getAs<RecordType>();
3151  assert(Rec && "Invalid NSConstantStringType");
3152  NSConstantStringTypeDecl = Rec->getDecl();
3153}
3154
3155QualType ASTContext::getObjCFastEnumerationStateType() {
3156  if (!ObjCFastEnumerationStateTypeDecl) {
3157    ObjCFastEnumerationStateTypeDecl =
3158      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3159                       &Idents.get("__objcFastEnumerationState"));
3160    ObjCFastEnumerationStateTypeDecl->startDefinition();
3161
3162    QualType FieldTypes[] = {
3163      UnsignedLongTy,
3164      getPointerType(ObjCIdTypedefType),
3165      getPointerType(UnsignedLongTy),
3166      getConstantArrayType(UnsignedLongTy,
3167                           llvm::APInt(32, 5), ArrayType::Normal, 0)
3168    };
3169
3170    for (size_t i = 0; i < 4; ++i) {
3171      FieldDecl *Field = FieldDecl::Create(*this,
3172                                           ObjCFastEnumerationStateTypeDecl,
3173                                           SourceLocation(), 0,
3174                                           FieldTypes[i], /*TInfo=*/0,
3175                                           /*BitWidth=*/0,
3176                                           /*Mutable=*/false);
3177      Field->setAccess(AS_public);
3178      ObjCFastEnumerationStateTypeDecl->addDecl(Field);
3179    }
3180
3181    ObjCFastEnumerationStateTypeDecl->completeDefinition();
3182  }
3183
3184  return getTagDeclType(ObjCFastEnumerationStateTypeDecl);
3185}
3186
3187QualType ASTContext::getBlockDescriptorType() {
3188  if (BlockDescriptorType)
3189    return getTagDeclType(BlockDescriptorType);
3190
3191  RecordDecl *T;
3192  // FIXME: Needs the FlagAppleBlock bit.
3193  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3194                       &Idents.get("__block_descriptor"));
3195  T->startDefinition();
3196
3197  QualType FieldTypes[] = {
3198    UnsignedLongTy,
3199    UnsignedLongTy,
3200  };
3201
3202  const char *FieldNames[] = {
3203    "reserved",
3204    "Size"
3205  };
3206
3207  for (size_t i = 0; i < 2; ++i) {
3208    FieldDecl *Field = FieldDecl::Create(*this,
3209                                         T,
3210                                         SourceLocation(),
3211                                         &Idents.get(FieldNames[i]),
3212                                         FieldTypes[i], /*TInfo=*/0,
3213                                         /*BitWidth=*/0,
3214                                         /*Mutable=*/false);
3215    Field->setAccess(AS_public);
3216    T->addDecl(Field);
3217  }
3218
3219  T->completeDefinition();
3220
3221  BlockDescriptorType = T;
3222
3223  return getTagDeclType(BlockDescriptorType);
3224}
3225
3226void ASTContext::setBlockDescriptorType(QualType T) {
3227  const RecordType *Rec = T->getAs<RecordType>();
3228  assert(Rec && "Invalid BlockDescriptorType");
3229  BlockDescriptorType = Rec->getDecl();
3230}
3231
3232QualType ASTContext::getBlockDescriptorExtendedType() {
3233  if (BlockDescriptorExtendedType)
3234    return getTagDeclType(BlockDescriptorExtendedType);
3235
3236  RecordDecl *T;
3237  // FIXME: Needs the FlagAppleBlock bit.
3238  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3239                       &Idents.get("__block_descriptor_withcopydispose"));
3240  T->startDefinition();
3241
3242  QualType FieldTypes[] = {
3243    UnsignedLongTy,
3244    UnsignedLongTy,
3245    getPointerType(VoidPtrTy),
3246    getPointerType(VoidPtrTy)
3247  };
3248
3249  const char *FieldNames[] = {
3250    "reserved",
3251    "Size",
3252    "CopyFuncPtr",
3253    "DestroyFuncPtr"
3254  };
3255
3256  for (size_t i = 0; i < 4; ++i) {
3257    FieldDecl *Field = FieldDecl::Create(*this,
3258                                         T,
3259                                         SourceLocation(),
3260                                         &Idents.get(FieldNames[i]),
3261                                         FieldTypes[i], /*TInfo=*/0,
3262                                         /*BitWidth=*/0,
3263                                         /*Mutable=*/false);
3264    Field->setAccess(AS_public);
3265    T->addDecl(Field);
3266  }
3267
3268  T->completeDefinition();
3269
3270  BlockDescriptorExtendedType = T;
3271
3272  return getTagDeclType(BlockDescriptorExtendedType);
3273}
3274
3275void ASTContext::setBlockDescriptorExtendedType(QualType T) {
3276  const RecordType *Rec = T->getAs<RecordType>();
3277  assert(Rec && "Invalid BlockDescriptorType");
3278  BlockDescriptorExtendedType = Rec->getDecl();
3279}
3280
3281bool ASTContext::BlockRequiresCopying(QualType Ty) {
3282  if (Ty->isBlockPointerType())
3283    return true;
3284  if (isObjCNSObjectType(Ty))
3285    return true;
3286  if (Ty->isObjCObjectPointerType())
3287    return true;
3288  return false;
3289}
3290
3291QualType ASTContext::BuildByRefType(llvm::StringRef DeclName, QualType Ty) {
3292  //  type = struct __Block_byref_1_X {
3293  //    void *__isa;
3294  //    struct __Block_byref_1_X *__forwarding;
3295  //    unsigned int __flags;
3296  //    unsigned int __size;
3297  //    void *__copy_helper;            // as needed
3298  //    void *__destroy_help            // as needed
3299  //    int X;
3300  //  } *
3301
3302  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3303
3304  // FIXME: Move up
3305  llvm::SmallString<36> Name;
3306  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3307                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3308  RecordDecl *T;
3309  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3310                       &Idents.get(Name.str()));
3311  T->startDefinition();
3312  QualType Int32Ty = IntTy;
3313  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3314  QualType FieldTypes[] = {
3315    getPointerType(VoidPtrTy),
3316    getPointerType(getTagDeclType(T)),
3317    Int32Ty,
3318    Int32Ty,
3319    getPointerType(VoidPtrTy),
3320    getPointerType(VoidPtrTy),
3321    Ty
3322  };
3323
3324  llvm::StringRef FieldNames[] = {
3325    "__isa",
3326    "__forwarding",
3327    "__flags",
3328    "__size",
3329    "__copy_helper",
3330    "__destroy_helper",
3331    DeclName,
3332  };
3333
3334  for (size_t i = 0; i < 7; ++i) {
3335    if (!HasCopyAndDispose && i >=4 && i <= 5)
3336      continue;
3337    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3338                                         &Idents.get(FieldNames[i]),
3339                                         FieldTypes[i], /*TInfo=*/0,
3340                                         /*BitWidth=*/0, /*Mutable=*/false);
3341    Field->setAccess(AS_public);
3342    T->addDecl(Field);
3343  }
3344
3345  T->completeDefinition();
3346
3347  return getPointerType(getTagDeclType(T));
3348}
3349
3350
3351QualType ASTContext::getBlockParmType(
3352  bool BlockHasCopyDispose,
3353  llvm::SmallVectorImpl<const Expr *> &Layout) {
3354
3355  // FIXME: Move up
3356  llvm::SmallString<36> Name;
3357  llvm::raw_svector_ostream(Name) << "__block_literal_"
3358                                  << ++UniqueBlockParmTypeID;
3359  RecordDecl *T;
3360  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3361                       &Idents.get(Name.str()));
3362  T->startDefinition();
3363  QualType FieldTypes[] = {
3364    getPointerType(VoidPtrTy),
3365    IntTy,
3366    IntTy,
3367    getPointerType(VoidPtrTy),
3368    (BlockHasCopyDispose ?
3369     getPointerType(getBlockDescriptorExtendedType()) :
3370     getPointerType(getBlockDescriptorType()))
3371  };
3372
3373  const char *FieldNames[] = {
3374    "__isa",
3375    "__flags",
3376    "__reserved",
3377    "__FuncPtr",
3378    "__descriptor"
3379  };
3380
3381  for (size_t i = 0; i < 5; ++i) {
3382    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3383                                         &Idents.get(FieldNames[i]),
3384                                         FieldTypes[i], /*TInfo=*/0,
3385                                         /*BitWidth=*/0, /*Mutable=*/false);
3386    Field->setAccess(AS_public);
3387    T->addDecl(Field);
3388  }
3389
3390  for (unsigned i = 0; i < Layout.size(); ++i) {
3391    const Expr *E = Layout[i];
3392
3393    QualType FieldType = E->getType();
3394    IdentifierInfo *FieldName = 0;
3395    if (isa<CXXThisExpr>(E)) {
3396      FieldName = &Idents.get("this");
3397    } else if (const BlockDeclRefExpr *BDRE = dyn_cast<BlockDeclRefExpr>(E)) {
3398      const ValueDecl *D = BDRE->getDecl();
3399      FieldName = D->getIdentifier();
3400      if (BDRE->isByRef())
3401        FieldType = BuildByRefType(D->getName(), FieldType);
3402    } else {
3403      // Padding.
3404      assert(isa<ConstantArrayType>(FieldType) &&
3405             isa<DeclRefExpr>(E) &&
3406             !cast<DeclRefExpr>(E)->getDecl()->getDeclName() &&
3407             "doesn't match characteristics of padding decl");
3408    }
3409
3410    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3411                                         FieldName, FieldType, /*TInfo=*/0,
3412                                         /*BitWidth=*/0, /*Mutable=*/false);
3413    Field->setAccess(AS_public);
3414    T->addDecl(Field);
3415  }
3416
3417  T->completeDefinition();
3418
3419  return getPointerType(getTagDeclType(T));
3420}
3421
3422void ASTContext::setObjCFastEnumerationStateType(QualType T) {
3423  const RecordType *Rec = T->getAs<RecordType>();
3424  assert(Rec && "Invalid ObjCFAstEnumerationStateType");
3425  ObjCFastEnumerationStateTypeDecl = Rec->getDecl();
3426}
3427
3428// This returns true if a type has been typedefed to BOOL:
3429// typedef <type> BOOL;
3430static bool isTypeTypedefedAsBOOL(QualType T) {
3431  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3432    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3433      return II->isStr("BOOL");
3434
3435  return false;
3436}
3437
3438/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3439/// purpose.
3440CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) {
3441  CharUnits sz = getTypeSizeInChars(type);
3442
3443  // Make all integer and enum types at least as large as an int
3444  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3445    sz = std::max(sz, getTypeSizeInChars(IntTy));
3446  // Treat arrays as pointers, since that's how they're passed in.
3447  else if (type->isArrayType())
3448    sz = getTypeSizeInChars(VoidPtrTy);
3449  return sz;
3450}
3451
3452static inline
3453std::string charUnitsToString(const CharUnits &CU) {
3454  return llvm::itostr(CU.getQuantity());
3455}
3456
3457/// getObjCEncodingForBlockDecl - Return the encoded type for this block
3458/// declaration.
3459void ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr,
3460                                             std::string& S) {
3461  const BlockDecl *Decl = Expr->getBlockDecl();
3462  QualType BlockTy =
3463      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3464  // Encode result type.
3465  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3466  // Compute size of all parameters.
3467  // Start with computing size of a pointer in number of bytes.
3468  // FIXME: There might(should) be a better way of doing this computation!
3469  SourceLocation Loc;
3470  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3471  CharUnits ParmOffset = PtrSize;
3472  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3473       E = Decl->param_end(); PI != E; ++PI) {
3474    QualType PType = (*PI)->getType();
3475    CharUnits sz = getObjCEncodingTypeSize(PType);
3476    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3477    ParmOffset += sz;
3478  }
3479  // Size of the argument frame
3480  S += charUnitsToString(ParmOffset);
3481  // Block pointer and offset.
3482  S += "@?0";
3483  ParmOffset = PtrSize;
3484
3485  // Argument types.
3486  ParmOffset = PtrSize;
3487  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3488       Decl->param_end(); PI != E; ++PI) {
3489    ParmVarDecl *PVDecl = *PI;
3490    QualType PType = PVDecl->getOriginalType();
3491    if (const ArrayType *AT =
3492          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3493      // Use array's original type only if it has known number of
3494      // elements.
3495      if (!isa<ConstantArrayType>(AT))
3496        PType = PVDecl->getType();
3497    } else if (PType->isFunctionType())
3498      PType = PVDecl->getType();
3499    getObjCEncodingForType(PType, S);
3500    S += charUnitsToString(ParmOffset);
3501    ParmOffset += getObjCEncodingTypeSize(PType);
3502  }
3503}
3504
3505/// getObjCEncodingForMethodDecl - Return the encoded type for this method
3506/// declaration.
3507void ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
3508                                              std::string& S) {
3509  // FIXME: This is not very efficient.
3510  // Encode type qualifer, 'in', 'inout', etc. for the return type.
3511  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
3512  // Encode result type.
3513  getObjCEncodingForType(Decl->getResultType(), S);
3514  // Compute size of all parameters.
3515  // Start with computing size of a pointer in number of bytes.
3516  // FIXME: There might(should) be a better way of doing this computation!
3517  SourceLocation Loc;
3518  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3519  // The first two arguments (self and _cmd) are pointers; account for
3520  // their size.
3521  CharUnits ParmOffset = 2 * PtrSize;
3522  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3523       E = Decl->sel_param_end(); PI != E; ++PI) {
3524    QualType PType = (*PI)->getType();
3525    CharUnits sz = getObjCEncodingTypeSize(PType);
3526    assert (sz.isPositive() &&
3527        "getObjCEncodingForMethodDecl - Incomplete param type");
3528    ParmOffset += sz;
3529  }
3530  S += charUnitsToString(ParmOffset);
3531  S += "@0:";
3532  S += charUnitsToString(PtrSize);
3533
3534  // Argument types.
3535  ParmOffset = 2 * PtrSize;
3536  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3537       E = Decl->sel_param_end(); PI != E; ++PI) {
3538    ParmVarDecl *PVDecl = *PI;
3539    QualType PType = PVDecl->getOriginalType();
3540    if (const ArrayType *AT =
3541          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3542      // Use array's original type only if it has known number of
3543      // elements.
3544      if (!isa<ConstantArrayType>(AT))
3545        PType = PVDecl->getType();
3546    } else if (PType->isFunctionType())
3547      PType = PVDecl->getType();
3548    // Process argument qualifiers for user supplied arguments; such as,
3549    // 'in', 'inout', etc.
3550    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
3551    getObjCEncodingForType(PType, S);
3552    S += charUnitsToString(ParmOffset);
3553    ParmOffset += getObjCEncodingTypeSize(PType);
3554  }
3555}
3556
3557/// getObjCEncodingForPropertyDecl - Return the encoded type for this
3558/// property declaration. If non-NULL, Container must be either an
3559/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
3560/// NULL when getting encodings for protocol properties.
3561/// Property attributes are stored as a comma-delimited C string. The simple
3562/// attributes readonly and bycopy are encoded as single characters. The
3563/// parametrized attributes, getter=name, setter=name, and ivar=name, are
3564/// encoded as single characters, followed by an identifier. Property types
3565/// are also encoded as a parametrized attribute. The characters used to encode
3566/// these attributes are defined by the following enumeration:
3567/// @code
3568/// enum PropertyAttributes {
3569/// kPropertyReadOnly = 'R',   // property is read-only.
3570/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
3571/// kPropertyByref = '&',  // property is a reference to the value last assigned
3572/// kPropertyDynamic = 'D',    // property is dynamic
3573/// kPropertyGetter = 'G',     // followed by getter selector name
3574/// kPropertySetter = 'S',     // followed by setter selector name
3575/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
3576/// kPropertyType = 't'              // followed by old-style type encoding.
3577/// kPropertyWeak = 'W'              // 'weak' property
3578/// kPropertyStrong = 'P'            // property GC'able
3579/// kPropertyNonAtomic = 'N'         // property non-atomic
3580/// };
3581/// @endcode
3582void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
3583                                                const Decl *Container,
3584                                                std::string& S) {
3585  // Collect information from the property implementation decl(s).
3586  bool Dynamic = false;
3587  ObjCPropertyImplDecl *SynthesizePID = 0;
3588
3589  // FIXME: Duplicated code due to poor abstraction.
3590  if (Container) {
3591    if (const ObjCCategoryImplDecl *CID =
3592        dyn_cast<ObjCCategoryImplDecl>(Container)) {
3593      for (ObjCCategoryImplDecl::propimpl_iterator
3594             i = CID->propimpl_begin(), e = CID->propimpl_end();
3595           i != e; ++i) {
3596        ObjCPropertyImplDecl *PID = *i;
3597        if (PID->getPropertyDecl() == PD) {
3598          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3599            Dynamic = true;
3600          } else {
3601            SynthesizePID = PID;
3602          }
3603        }
3604      }
3605    } else {
3606      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
3607      for (ObjCCategoryImplDecl::propimpl_iterator
3608             i = OID->propimpl_begin(), e = OID->propimpl_end();
3609           i != e; ++i) {
3610        ObjCPropertyImplDecl *PID = *i;
3611        if (PID->getPropertyDecl() == PD) {
3612          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3613            Dynamic = true;
3614          } else {
3615            SynthesizePID = PID;
3616          }
3617        }
3618      }
3619    }
3620  }
3621
3622  // FIXME: This is not very efficient.
3623  S = "T";
3624
3625  // Encode result type.
3626  // GCC has some special rules regarding encoding of properties which
3627  // closely resembles encoding of ivars.
3628  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
3629                             true /* outermost type */,
3630                             true /* encoding for property */);
3631
3632  if (PD->isReadOnly()) {
3633    S += ",R";
3634  } else {
3635    switch (PD->getSetterKind()) {
3636    case ObjCPropertyDecl::Assign: break;
3637    case ObjCPropertyDecl::Copy:   S += ",C"; break;
3638    case ObjCPropertyDecl::Retain: S += ",&"; break;
3639    }
3640  }
3641
3642  // It really isn't clear at all what this means, since properties
3643  // are "dynamic by default".
3644  if (Dynamic)
3645    S += ",D";
3646
3647  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
3648    S += ",N";
3649
3650  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
3651    S += ",G";
3652    S += PD->getGetterName().getAsString();
3653  }
3654
3655  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
3656    S += ",S";
3657    S += PD->getSetterName().getAsString();
3658  }
3659
3660  if (SynthesizePID) {
3661    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
3662    S += ",V";
3663    S += OID->getNameAsString();
3664  }
3665
3666  // FIXME: OBJCGC: weak & strong
3667}
3668
3669/// getLegacyIntegralTypeEncoding -
3670/// Another legacy compatibility encoding: 32-bit longs are encoded as
3671/// 'l' or 'L' , but not always.  For typedefs, we need to use
3672/// 'i' or 'I' instead if encoding a struct field, or a pointer!
3673///
3674void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
3675  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
3676    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
3677      if (BT->getKind() == BuiltinType::ULong &&
3678          ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3679        PointeeTy = UnsignedIntTy;
3680      else
3681        if (BT->getKind() == BuiltinType::Long &&
3682            ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3683          PointeeTy = IntTy;
3684    }
3685  }
3686}
3687
3688void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
3689                                        const FieldDecl *Field) {
3690  // We follow the behavior of gcc, expanding structures which are
3691  // directly pointed to, and expanding embedded structures. Note that
3692  // these rules are sufficient to prevent recursive encoding of the
3693  // same type.
3694  getObjCEncodingForTypeImpl(T, S, true, true, Field,
3695                             true /* outermost type */);
3696}
3697
3698static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
3699    switch (T->getAs<BuiltinType>()->getKind()) {
3700    default: assert(0 && "Unhandled builtin type kind");
3701    case BuiltinType::Void:       return 'v';
3702    case BuiltinType::Bool:       return 'B';
3703    case BuiltinType::Char_U:
3704    case BuiltinType::UChar:      return 'C';
3705    case BuiltinType::UShort:     return 'S';
3706    case BuiltinType::UInt:       return 'I';
3707    case BuiltinType::ULong:
3708        return
3709          (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'L' : 'Q';
3710    case BuiltinType::UInt128:    return 'T';
3711    case BuiltinType::ULongLong:  return 'Q';
3712    case BuiltinType::Char_S:
3713    case BuiltinType::SChar:      return 'c';
3714    case BuiltinType::Short:      return 's';
3715    case BuiltinType::WChar:
3716    case BuiltinType::Int:        return 'i';
3717    case BuiltinType::Long:
3718      return
3719        (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'l' : 'q';
3720    case BuiltinType::LongLong:   return 'q';
3721    case BuiltinType::Int128:     return 't';
3722    case BuiltinType::Float:      return 'f';
3723    case BuiltinType::Double:     return 'd';
3724    case BuiltinType::LongDouble: return 'D';
3725    }
3726}
3727
3728static void EncodeBitField(const ASTContext *Context, std::string& S,
3729                           QualType T, const FieldDecl *FD) {
3730  const Expr *E = FD->getBitWidth();
3731  assert(E && "bitfield width not there - getObjCEncodingForTypeImpl");
3732  ASTContext *Ctx = const_cast<ASTContext*>(Context);
3733  S += 'b';
3734  // The NeXT runtime encodes bit fields as b followed by the number of bits.
3735  // The GNU runtime requires more information; bitfields are encoded as b,
3736  // then the offset (in bits) of the first element, then the type of the
3737  // bitfield, then the size in bits.  For example, in this structure:
3738  //
3739  // struct
3740  // {
3741  //    int integer;
3742  //    int flags:2;
3743  // };
3744  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
3745  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
3746  // information is not especially sensible, but we're stuck with it for
3747  // compatibility with GCC, although providing it breaks anything that
3748  // actually uses runtime introspection and wants to work on both runtimes...
3749  if (!Ctx->getLangOptions().NeXTRuntime) {
3750    const RecordDecl *RD = FD->getParent();
3751    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
3752    // FIXME: This same linear search is also used in ExprConstant - it might
3753    // be better if the FieldDecl stored its offset.  We'd be increasing the
3754    // size of the object slightly, but saving some time every time it is used.
3755    unsigned i = 0;
3756    for (RecordDecl::field_iterator Field = RD->field_begin(),
3757                                 FieldEnd = RD->field_end();
3758         Field != FieldEnd; (void)++Field, ++i) {
3759      if (*Field == FD)
3760        break;
3761    }
3762    S += llvm::utostr(RL.getFieldOffset(i));
3763    S += ObjCEncodingForPrimitiveKind(Context, T);
3764  }
3765  unsigned N = E->EvaluateAsInt(*Ctx).getZExtValue();
3766  S += llvm::utostr(N);
3767}
3768
3769// FIXME: Use SmallString for accumulating string.
3770void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
3771                                            bool ExpandPointedToStructures,
3772                                            bool ExpandStructures,
3773                                            const FieldDecl *FD,
3774                                            bool OutermostType,
3775                                            bool EncodingProperty) {
3776  if (T->getAs<BuiltinType>()) {
3777    if (FD && FD->isBitField())
3778      return EncodeBitField(this, S, T, FD);
3779    S += ObjCEncodingForPrimitiveKind(this, T);
3780    return;
3781  }
3782
3783  if (const ComplexType *CT = T->getAs<ComplexType>()) {
3784    S += 'j';
3785    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
3786                               false);
3787    return;
3788  }
3789
3790  // encoding for pointer or r3eference types.
3791  QualType PointeeTy;
3792  if (const PointerType *PT = T->getAs<PointerType>()) {
3793    if (PT->isObjCSelType()) {
3794      S += ':';
3795      return;
3796    }
3797    PointeeTy = PT->getPointeeType();
3798  }
3799  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3800    PointeeTy = RT->getPointeeType();
3801  if (!PointeeTy.isNull()) {
3802    bool isReadOnly = false;
3803    // For historical/compatibility reasons, the read-only qualifier of the
3804    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
3805    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
3806    // Also, do not emit the 'r' for anything but the outermost type!
3807    if (isa<TypedefType>(T.getTypePtr())) {
3808      if (OutermostType && T.isConstQualified()) {
3809        isReadOnly = true;
3810        S += 'r';
3811      }
3812    } else if (OutermostType) {
3813      QualType P = PointeeTy;
3814      while (P->getAs<PointerType>())
3815        P = P->getAs<PointerType>()->getPointeeType();
3816      if (P.isConstQualified()) {
3817        isReadOnly = true;
3818        S += 'r';
3819      }
3820    }
3821    if (isReadOnly) {
3822      // Another legacy compatibility encoding. Some ObjC qualifier and type
3823      // combinations need to be rearranged.
3824      // Rewrite "in const" from "nr" to "rn"
3825      if (llvm::StringRef(S).endswith("nr"))
3826        S.replace(S.end()-2, S.end(), "rn");
3827    }
3828
3829    if (PointeeTy->isCharType()) {
3830      // char pointer types should be encoded as '*' unless it is a
3831      // type that has been typedef'd to 'BOOL'.
3832      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
3833        S += '*';
3834        return;
3835      }
3836    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
3837      // GCC binary compat: Need to convert "struct objc_class *" to "#".
3838      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
3839        S += '#';
3840        return;
3841      }
3842      // GCC binary compat: Need to convert "struct objc_object *" to "@".
3843      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
3844        S += '@';
3845        return;
3846      }
3847      // fall through...
3848    }
3849    S += '^';
3850    getLegacyIntegralTypeEncoding(PointeeTy);
3851
3852    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
3853                               NULL);
3854    return;
3855  }
3856
3857  if (const ArrayType *AT =
3858      // Ignore type qualifiers etc.
3859        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
3860    if (isa<IncompleteArrayType>(AT)) {
3861      // Incomplete arrays are encoded as a pointer to the array element.
3862      S += '^';
3863
3864      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3865                                 false, ExpandStructures, FD);
3866    } else {
3867      S += '[';
3868
3869      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
3870        S += llvm::utostr(CAT->getSize().getZExtValue());
3871      else {
3872        //Variable length arrays are encoded as a regular array with 0 elements.
3873        assert(isa<VariableArrayType>(AT) && "Unknown array type!");
3874        S += '0';
3875      }
3876
3877      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3878                                 false, ExpandStructures, FD);
3879      S += ']';
3880    }
3881    return;
3882  }
3883
3884  if (T->getAs<FunctionType>()) {
3885    S += '?';
3886    return;
3887  }
3888
3889  if (const RecordType *RTy = T->getAs<RecordType>()) {
3890    RecordDecl *RDecl = RTy->getDecl();
3891    S += RDecl->isUnion() ? '(' : '{';
3892    // Anonymous structures print as '?'
3893    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
3894      S += II->getName();
3895      if (ClassTemplateSpecializationDecl *Spec
3896          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
3897        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
3898        std::string TemplateArgsStr
3899          = TemplateSpecializationType::PrintTemplateArgumentList(
3900                                            TemplateArgs.getFlatArgumentList(),
3901                                            TemplateArgs.flat_size(),
3902                                            (*this).PrintingPolicy);
3903
3904        S += TemplateArgsStr;
3905      }
3906    } else {
3907      S += '?';
3908    }
3909    if (ExpandStructures) {
3910      S += '=';
3911      for (RecordDecl::field_iterator Field = RDecl->field_begin(),
3912                                   FieldEnd = RDecl->field_end();
3913           Field != FieldEnd; ++Field) {
3914        if (FD) {
3915          S += '"';
3916          S += Field->getNameAsString();
3917          S += '"';
3918        }
3919
3920        // Special case bit-fields.
3921        if (Field->isBitField()) {
3922          getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
3923                                     (*Field));
3924        } else {
3925          QualType qt = Field->getType();
3926          getLegacyIntegralTypeEncoding(qt);
3927          getObjCEncodingForTypeImpl(qt, S, false, true,
3928                                     FD);
3929        }
3930      }
3931    }
3932    S += RDecl->isUnion() ? ')' : '}';
3933    return;
3934  }
3935
3936  if (T->isEnumeralType()) {
3937    if (FD && FD->isBitField())
3938      EncodeBitField(this, S, T, FD);
3939    else
3940      S += 'i';
3941    return;
3942  }
3943
3944  if (T->isBlockPointerType()) {
3945    S += "@?"; // Unlike a pointer-to-function, which is "^?".
3946    return;
3947  }
3948
3949  // Ignore protocol qualifiers when mangling at this level.
3950  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
3951    T = OT->getBaseType();
3952
3953  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
3954    // @encode(class_name)
3955    ObjCInterfaceDecl *OI = OIT->getDecl();
3956    S += '{';
3957    const IdentifierInfo *II = OI->getIdentifier();
3958    S += II->getName();
3959    S += '=';
3960    llvm::SmallVector<ObjCIvarDecl*, 32> Ivars;
3961    DeepCollectObjCIvars(OI, true, Ivars);
3962    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
3963      FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
3964      if (Field->isBitField())
3965        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
3966      else
3967        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
3968    }
3969    S += '}';
3970    return;
3971  }
3972
3973  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
3974    if (OPT->isObjCIdType()) {
3975      S += '@';
3976      return;
3977    }
3978
3979    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
3980      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
3981      // Since this is a binary compatibility issue, need to consult with runtime
3982      // folks. Fortunately, this is a *very* obsure construct.
3983      S += '#';
3984      return;
3985    }
3986
3987    if (OPT->isObjCQualifiedIdType()) {
3988      getObjCEncodingForTypeImpl(getObjCIdType(), S,
3989                                 ExpandPointedToStructures,
3990                                 ExpandStructures, FD);
3991      if (FD || EncodingProperty) {
3992        // Note that we do extended encoding of protocol qualifer list
3993        // Only when doing ivar or property encoding.
3994        S += '"';
3995        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3996             E = OPT->qual_end(); I != E; ++I) {
3997          S += '<';
3998          S += (*I)->getNameAsString();
3999          S += '>';
4000        }
4001        S += '"';
4002      }
4003      return;
4004    }
4005
4006    QualType PointeeTy = OPT->getPointeeType();
4007    if (!EncodingProperty &&
4008        isa<TypedefType>(PointeeTy.getTypePtr())) {
4009      // Another historical/compatibility reason.
4010      // We encode the underlying type which comes out as
4011      // {...};
4012      S += '^';
4013      getObjCEncodingForTypeImpl(PointeeTy, S,
4014                                 false, ExpandPointedToStructures,
4015                                 NULL);
4016      return;
4017    }
4018
4019    S += '@';
4020    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
4021      S += '"';
4022      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4023      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4024           E = OPT->qual_end(); I != E; ++I) {
4025        S += '<';
4026        S += (*I)->getNameAsString();
4027        S += '>';
4028      }
4029      S += '"';
4030    }
4031    return;
4032  }
4033
4034  // gcc just blithely ignores member pointers.
4035  // TODO: maybe there should be a mangling for these
4036  if (T->getAs<MemberPointerType>())
4037    return;
4038
4039  if (T->isVectorType()) {
4040    // This matches gcc's encoding, even though technically it is
4041    // insufficient.
4042    // FIXME. We should do a better job than gcc.
4043    return;
4044  }
4045
4046  assert(0 && "@encode for type not implemented!");
4047}
4048
4049void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4050                                                 std::string& S) const {
4051  if (QT & Decl::OBJC_TQ_In)
4052    S += 'n';
4053  if (QT & Decl::OBJC_TQ_Inout)
4054    S += 'N';
4055  if (QT & Decl::OBJC_TQ_Out)
4056    S += 'o';
4057  if (QT & Decl::OBJC_TQ_Bycopy)
4058    S += 'O';
4059  if (QT & Decl::OBJC_TQ_Byref)
4060    S += 'R';
4061  if (QT & Decl::OBJC_TQ_Oneway)
4062    S += 'V';
4063}
4064
4065void ASTContext::setBuiltinVaListType(QualType T) {
4066  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4067
4068  BuiltinVaListType = T;
4069}
4070
4071void ASTContext::setObjCIdType(QualType T) {
4072  ObjCIdTypedefType = T;
4073}
4074
4075void ASTContext::setObjCSelType(QualType T) {
4076  ObjCSelTypedefType = T;
4077}
4078
4079void ASTContext::setObjCProtoType(QualType QT) {
4080  ObjCProtoType = QT;
4081}
4082
4083void ASTContext::setObjCClassType(QualType T) {
4084  ObjCClassTypedefType = T;
4085}
4086
4087void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4088  assert(ObjCConstantStringType.isNull() &&
4089         "'NSConstantString' type already set!");
4090
4091  ObjCConstantStringType = getObjCInterfaceType(Decl);
4092}
4093
4094/// \brief Retrieve the template name that corresponds to a non-empty
4095/// lookup.
4096TemplateName ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4097                                                   UnresolvedSetIterator End) {
4098  unsigned size = End - Begin;
4099  assert(size > 1 && "set is not overloaded!");
4100
4101  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4102                          size * sizeof(FunctionTemplateDecl*));
4103  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4104
4105  NamedDecl **Storage = OT->getStorage();
4106  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4107    NamedDecl *D = *I;
4108    assert(isa<FunctionTemplateDecl>(D) ||
4109           (isa<UsingShadowDecl>(D) &&
4110            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4111    *Storage++ = D;
4112  }
4113
4114  return TemplateName(OT);
4115}
4116
4117/// \brief Retrieve the template name that represents a qualified
4118/// template name such as \c std::vector.
4119TemplateName ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4120                                                  bool TemplateKeyword,
4121                                                  TemplateDecl *Template) {
4122  // FIXME: Canonicalization?
4123  llvm::FoldingSetNodeID ID;
4124  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4125
4126  void *InsertPos = 0;
4127  QualifiedTemplateName *QTN =
4128    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4129  if (!QTN) {
4130    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4131    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4132  }
4133
4134  return TemplateName(QTN);
4135}
4136
4137/// \brief Retrieve the template name that represents a dependent
4138/// template name such as \c MetaFun::template apply.
4139TemplateName ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4140                                                  const IdentifierInfo *Name) {
4141  assert((!NNS || NNS->isDependent()) &&
4142         "Nested name specifier must be dependent");
4143
4144  llvm::FoldingSetNodeID ID;
4145  DependentTemplateName::Profile(ID, NNS, Name);
4146
4147  void *InsertPos = 0;
4148  DependentTemplateName *QTN =
4149    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4150
4151  if (QTN)
4152    return TemplateName(QTN);
4153
4154  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4155  if (CanonNNS == NNS) {
4156    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4157  } else {
4158    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4159    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4160    DependentTemplateName *CheckQTN =
4161      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4162    assert(!CheckQTN && "Dependent type name canonicalization broken");
4163    (void)CheckQTN;
4164  }
4165
4166  DependentTemplateNames.InsertNode(QTN, InsertPos);
4167  return TemplateName(QTN);
4168}
4169
4170/// \brief Retrieve the template name that represents a dependent
4171/// template name such as \c MetaFun::template operator+.
4172TemplateName
4173ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4174                                     OverloadedOperatorKind Operator) {
4175  assert((!NNS || NNS->isDependent()) &&
4176         "Nested name specifier must be dependent");
4177
4178  llvm::FoldingSetNodeID ID;
4179  DependentTemplateName::Profile(ID, NNS, Operator);
4180
4181  void *InsertPos = 0;
4182  DependentTemplateName *QTN
4183    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4184
4185  if (QTN)
4186    return TemplateName(QTN);
4187
4188  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4189  if (CanonNNS == NNS) {
4190    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4191  } else {
4192    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4193    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4194
4195    DependentTemplateName *CheckQTN
4196      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4197    assert(!CheckQTN && "Dependent template name canonicalization broken");
4198    (void)CheckQTN;
4199  }
4200
4201  DependentTemplateNames.InsertNode(QTN, InsertPos);
4202  return TemplateName(QTN);
4203}
4204
4205/// getFromTargetType - Given one of the integer types provided by
4206/// TargetInfo, produce the corresponding type. The unsigned @p Type
4207/// is actually a value of type @c TargetInfo::IntType.
4208CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4209  switch (Type) {
4210  case TargetInfo::NoInt: return CanQualType();
4211  case TargetInfo::SignedShort: return ShortTy;
4212  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4213  case TargetInfo::SignedInt: return IntTy;
4214  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4215  case TargetInfo::SignedLong: return LongTy;
4216  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4217  case TargetInfo::SignedLongLong: return LongLongTy;
4218  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4219  }
4220
4221  assert(false && "Unhandled TargetInfo::IntType value");
4222  return CanQualType();
4223}
4224
4225//===----------------------------------------------------------------------===//
4226//                        Type Predicates.
4227//===----------------------------------------------------------------------===//
4228
4229/// isObjCNSObjectType - Return true if this is an NSObject object using
4230/// NSObject attribute on a c-style pointer type.
4231/// FIXME - Make it work directly on types.
4232/// FIXME: Move to Type.
4233///
4234bool ASTContext::isObjCNSObjectType(QualType Ty) const {
4235  if (TypedefType *TDT = dyn_cast<TypedefType>(Ty)) {
4236    if (TypedefDecl *TD = TDT->getDecl())
4237      if (TD->getAttr<ObjCNSObjectAttr>())
4238        return true;
4239  }
4240  return false;
4241}
4242
4243/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4244/// garbage collection attribute.
4245///
4246Qualifiers::GC ASTContext::getObjCGCAttrKind(const QualType &Ty) const {
4247  Qualifiers::GC GCAttrs = Qualifiers::GCNone;
4248  if (getLangOptions().ObjC1 &&
4249      getLangOptions().getGCMode() != LangOptions::NonGC) {
4250    GCAttrs = Ty.getObjCGCAttr();
4251    // Default behavious under objective-c's gc is for objective-c pointers
4252    // (or pointers to them) be treated as though they were declared
4253    // as __strong.
4254    if (GCAttrs == Qualifiers::GCNone) {
4255      if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4256        GCAttrs = Qualifiers::Strong;
4257      else if (Ty->isPointerType())
4258        return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4259    }
4260    // Non-pointers have none gc'able attribute regardless of the attribute
4261    // set on them.
4262    else if (!Ty->isAnyPointerType() && !Ty->isBlockPointerType())
4263      return Qualifiers::GCNone;
4264  }
4265  return GCAttrs;
4266}
4267
4268//===----------------------------------------------------------------------===//
4269//                        Type Compatibility Testing
4270//===----------------------------------------------------------------------===//
4271
4272/// areCompatVectorTypes - Return true if the two specified vector types are
4273/// compatible.
4274static bool areCompatVectorTypes(const VectorType *LHS,
4275                                 const VectorType *RHS) {
4276  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
4277  return LHS->getElementType() == RHS->getElementType() &&
4278         LHS->getNumElements() == RHS->getNumElements();
4279}
4280
4281bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
4282                                          QualType SecondVec) {
4283  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
4284  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
4285
4286  if (hasSameUnqualifiedType(FirstVec, SecondVec))
4287    return true;
4288
4289  // AltiVec vectors types are identical to equivalent GCC vector types
4290  const VectorType *First = FirstVec->getAs<VectorType>();
4291  const VectorType *Second = SecondVec->getAs<VectorType>();
4292  if ((((First->getAltiVecSpecific() == VectorType::AltiVec) &&
4293        (Second->getAltiVecSpecific() == VectorType::NotAltiVec)) ||
4294       ((First->getAltiVecSpecific() == VectorType::NotAltiVec) &&
4295        (Second->getAltiVecSpecific() == VectorType::AltiVec))) &&
4296      hasSameType(First->getElementType(), Second->getElementType()) &&
4297      (First->getNumElements() == Second->getNumElements()))
4298    return true;
4299
4300  return false;
4301}
4302
4303//===----------------------------------------------------------------------===//
4304// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
4305//===----------------------------------------------------------------------===//
4306
4307/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
4308/// inheritance hierarchy of 'rProto'.
4309bool ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
4310                                                ObjCProtocolDecl *rProto) {
4311  if (lProto == rProto)
4312    return true;
4313  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
4314       E = rProto->protocol_end(); PI != E; ++PI)
4315    if (ProtocolCompatibleWithProtocol(lProto, *PI))
4316      return true;
4317  return false;
4318}
4319
4320/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
4321/// return true if lhs's protocols conform to rhs's protocol; false
4322/// otherwise.
4323bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
4324  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
4325    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
4326  return false;
4327}
4328
4329/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
4330/// Class<p1, ...>.
4331bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
4332                                                      QualType rhs) {
4333  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
4334  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4335  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
4336
4337  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4338       E = lhsQID->qual_end(); I != E; ++I) {
4339    bool match = false;
4340    ObjCProtocolDecl *lhsProto = *I;
4341    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4342         E = rhsOPT->qual_end(); J != E; ++J) {
4343      ObjCProtocolDecl *rhsProto = *J;
4344      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
4345        match = true;
4346        break;
4347      }
4348    }
4349    if (!match)
4350      return false;
4351  }
4352  return true;
4353}
4354
4355/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
4356/// ObjCQualifiedIDType.
4357bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
4358                                                   bool compare) {
4359  // Allow id<P..> and an 'id' or void* type in all cases.
4360  if (lhs->isVoidPointerType() ||
4361      lhs->isObjCIdType() || lhs->isObjCClassType())
4362    return true;
4363  else if (rhs->isVoidPointerType() ||
4364           rhs->isObjCIdType() || rhs->isObjCClassType())
4365    return true;
4366
4367  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
4368    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4369
4370    if (!rhsOPT) return false;
4371
4372    if (rhsOPT->qual_empty()) {
4373      // If the RHS is a unqualified interface pointer "NSString*",
4374      // make sure we check the class hierarchy.
4375      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4376        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4377             E = lhsQID->qual_end(); I != E; ++I) {
4378          // when comparing an id<P> on lhs with a static type on rhs,
4379          // see if static class implements all of id's protocols, directly or
4380          // through its super class and categories.
4381          if (!rhsID->ClassImplementsProtocol(*I, true))
4382            return false;
4383        }
4384      }
4385      // If there are no qualifiers and no interface, we have an 'id'.
4386      return true;
4387    }
4388    // Both the right and left sides have qualifiers.
4389    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4390         E = lhsQID->qual_end(); I != E; ++I) {
4391      ObjCProtocolDecl *lhsProto = *I;
4392      bool match = false;
4393
4394      // when comparing an id<P> on lhs with a static type on rhs,
4395      // see if static class implements all of id's protocols, directly or
4396      // through its super class and categories.
4397      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4398           E = rhsOPT->qual_end(); J != E; ++J) {
4399        ObjCProtocolDecl *rhsProto = *J;
4400        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4401            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4402          match = true;
4403          break;
4404        }
4405      }
4406      // If the RHS is a qualified interface pointer "NSString<P>*",
4407      // make sure we check the class hierarchy.
4408      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4409        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4410             E = lhsQID->qual_end(); I != E; ++I) {
4411          // when comparing an id<P> on lhs with a static type on rhs,
4412          // see if static class implements all of id's protocols, directly or
4413          // through its super class and categories.
4414          if (rhsID->ClassImplementsProtocol(*I, true)) {
4415            match = true;
4416            break;
4417          }
4418        }
4419      }
4420      if (!match)
4421        return false;
4422    }
4423
4424    return true;
4425  }
4426
4427  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
4428  assert(rhsQID && "One of the LHS/RHS should be id<x>");
4429
4430  if (const ObjCObjectPointerType *lhsOPT =
4431        lhs->getAsObjCInterfacePointerType()) {
4432    // If both the right and left sides have qualifiers.
4433    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
4434         E = lhsOPT->qual_end(); I != E; ++I) {
4435      ObjCProtocolDecl *lhsProto = *I;
4436      bool match = false;
4437
4438      // when comparing an id<P> on rhs with a static type on lhs,
4439      // see if static class implements all of id's protocols, directly or
4440      // through its super class and categories.
4441      // First, lhs protocols in the qualifier list must be found, direct
4442      // or indirect in rhs's qualifier list or it is a mismatch.
4443      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4444           E = rhsQID->qual_end(); J != E; ++J) {
4445        ObjCProtocolDecl *rhsProto = *J;
4446        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4447            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4448          match = true;
4449          break;
4450        }
4451      }
4452      if (!match)
4453        return false;
4454    }
4455
4456    // Static class's protocols, or its super class or category protocols
4457    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
4458    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
4459      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4460      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
4461      // This is rather dubious but matches gcc's behavior. If lhs has
4462      // no type qualifier and its class has no static protocol(s)
4463      // assume that it is mismatch.
4464      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
4465        return false;
4466      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4467           LHSInheritedProtocols.begin(),
4468           E = LHSInheritedProtocols.end(); I != E; ++I) {
4469        bool match = false;
4470        ObjCProtocolDecl *lhsProto = (*I);
4471        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4472             E = rhsQID->qual_end(); J != E; ++J) {
4473          ObjCProtocolDecl *rhsProto = *J;
4474          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4475              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4476            match = true;
4477            break;
4478          }
4479        }
4480        if (!match)
4481          return false;
4482      }
4483    }
4484    return true;
4485  }
4486  return false;
4487}
4488
4489/// canAssignObjCInterfaces - Return true if the two interface types are
4490/// compatible for assignment from RHS to LHS.  This handles validation of any
4491/// protocol qualifiers on the LHS or RHS.
4492///
4493bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
4494                                         const ObjCObjectPointerType *RHSOPT) {
4495  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4496  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4497
4498  // If either type represents the built-in 'id' or 'Class' types, return true.
4499  if (LHS->isObjCUnqualifiedIdOrClass() ||
4500      RHS->isObjCUnqualifiedIdOrClass())
4501    return true;
4502
4503  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
4504    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4505                                             QualType(RHSOPT,0),
4506                                             false);
4507
4508  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
4509    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
4510                                                QualType(RHSOPT,0));
4511
4512  // If we have 2 user-defined types, fall into that path.
4513  if (LHS->getInterface() && RHS->getInterface())
4514    return canAssignObjCInterfaces(LHS, RHS);
4515
4516  return false;
4517}
4518
4519/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
4520/// for providing type-safty for objective-c pointers used to pass/return
4521/// arguments in block literals. When passed as arguments, passing 'A*' where
4522/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
4523/// not OK. For the return type, the opposite is not OK.
4524bool ASTContext::canAssignObjCInterfacesInBlockPointer(
4525                                         const ObjCObjectPointerType *LHSOPT,
4526                                         const ObjCObjectPointerType *RHSOPT) {
4527  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
4528    return true;
4529
4530  if (LHSOPT->isObjCBuiltinType()) {
4531    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
4532  }
4533
4534  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
4535    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4536                                             QualType(RHSOPT,0),
4537                                             false);
4538
4539  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
4540  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
4541  if (LHS && RHS)  { // We have 2 user-defined types.
4542    if (LHS != RHS) {
4543      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
4544        return false;
4545      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
4546        return true;
4547    }
4548    else
4549      return true;
4550  }
4551  return false;
4552}
4553
4554/// getIntersectionOfProtocols - This routine finds the intersection of set
4555/// of protocols inherited from two distinct objective-c pointer objects.
4556/// It is used to build composite qualifier list of the composite type of
4557/// the conditional expression involving two objective-c pointer objects.
4558static
4559void getIntersectionOfProtocols(ASTContext &Context,
4560                                const ObjCObjectPointerType *LHSOPT,
4561                                const ObjCObjectPointerType *RHSOPT,
4562      llvm::SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
4563
4564  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4565  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4566  assert(LHS->getInterface() && "LHS must have an interface base");
4567  assert(RHS->getInterface() && "RHS must have an interface base");
4568
4569  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
4570  unsigned LHSNumProtocols = LHS->getNumProtocols();
4571  if (LHSNumProtocols > 0)
4572    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
4573  else {
4574    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4575    Context.CollectInheritedProtocols(LHS->getInterface(),
4576                                      LHSInheritedProtocols);
4577    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
4578                                LHSInheritedProtocols.end());
4579  }
4580
4581  unsigned RHSNumProtocols = RHS->getNumProtocols();
4582  if (RHSNumProtocols > 0) {
4583    ObjCProtocolDecl **RHSProtocols =
4584      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
4585    for (unsigned i = 0; i < RHSNumProtocols; ++i)
4586      if (InheritedProtocolSet.count(RHSProtocols[i]))
4587        IntersectionOfProtocols.push_back(RHSProtocols[i]);
4588  }
4589  else {
4590    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
4591    Context.CollectInheritedProtocols(RHS->getInterface(),
4592                                      RHSInheritedProtocols);
4593    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4594         RHSInheritedProtocols.begin(),
4595         E = RHSInheritedProtocols.end(); I != E; ++I)
4596      if (InheritedProtocolSet.count((*I)))
4597        IntersectionOfProtocols.push_back((*I));
4598  }
4599}
4600
4601/// areCommonBaseCompatible - Returns common base class of the two classes if
4602/// one found. Note that this is O'2 algorithm. But it will be called as the
4603/// last type comparison in a ?-exp of ObjC pointer types before a
4604/// warning is issued. So, its invokation is extremely rare.
4605QualType ASTContext::areCommonBaseCompatible(
4606                                          const ObjCObjectPointerType *Lptr,
4607                                          const ObjCObjectPointerType *Rptr) {
4608  const ObjCObjectType *LHS = Lptr->getObjectType();
4609  const ObjCObjectType *RHS = Rptr->getObjectType();
4610  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
4611  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
4612  if (!LDecl || !RDecl)
4613    return QualType();
4614
4615  while ((LDecl = LDecl->getSuperClass())) {
4616    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
4617    if (canAssignObjCInterfaces(LHS, RHS)) {
4618      llvm::SmallVector<ObjCProtocolDecl *, 8> Protocols;
4619      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
4620
4621      QualType Result = QualType(LHS, 0);
4622      if (!Protocols.empty())
4623        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
4624      Result = getObjCObjectPointerType(Result);
4625      return Result;
4626    }
4627  }
4628
4629  return QualType();
4630}
4631
4632bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
4633                                         const ObjCObjectType *RHS) {
4634  assert(LHS->getInterface() && "LHS is not an interface type");
4635  assert(RHS->getInterface() && "RHS is not an interface type");
4636
4637  // Verify that the base decls are compatible: the RHS must be a subclass of
4638  // the LHS.
4639  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
4640    return false;
4641
4642  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
4643  // protocol qualified at all, then we are good.
4644  if (LHS->getNumProtocols() == 0)
4645    return true;
4646
4647  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't, then it
4648  // isn't a superset.
4649  if (RHS->getNumProtocols() == 0)
4650    return true;  // FIXME: should return false!
4651
4652  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
4653                                     LHSPE = LHS->qual_end();
4654       LHSPI != LHSPE; LHSPI++) {
4655    bool RHSImplementsProtocol = false;
4656
4657    // If the RHS doesn't implement the protocol on the left, the types
4658    // are incompatible.
4659    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
4660                                       RHSPE = RHS->qual_end();
4661         RHSPI != RHSPE; RHSPI++) {
4662      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
4663        RHSImplementsProtocol = true;
4664        break;
4665      }
4666    }
4667    // FIXME: For better diagnostics, consider passing back the protocol name.
4668    if (!RHSImplementsProtocol)
4669      return false;
4670  }
4671  // The RHS implements all protocols listed on the LHS.
4672  return true;
4673}
4674
4675bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
4676  // get the "pointed to" types
4677  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
4678  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
4679
4680  if (!LHSOPT || !RHSOPT)
4681    return false;
4682
4683  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
4684         canAssignObjCInterfaces(RHSOPT, LHSOPT);
4685}
4686
4687bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
4688  return canAssignObjCInterfaces(
4689                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
4690                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
4691}
4692
4693/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
4694/// both shall have the identically qualified version of a compatible type.
4695/// C99 6.2.7p1: Two types have compatible types if their types are the
4696/// same. See 6.7.[2,3,5] for additional rules.
4697bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
4698                                    bool CompareUnqualified) {
4699  if (getLangOptions().CPlusPlus)
4700    return hasSameType(LHS, RHS);
4701
4702  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
4703}
4704
4705bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
4706  return !mergeTypes(LHS, RHS, true).isNull();
4707}
4708
4709/// mergeTransparentUnionType - if T is a transparent union type and a member
4710/// of T is compatible with SubType, return the merged type, else return
4711/// QualType()
4712QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
4713                                               bool OfBlockPointer,
4714                                               bool Unqualified) {
4715  if (const RecordType *UT = T->getAsUnionType()) {
4716    RecordDecl *UD = UT->getDecl();
4717    if (UD->hasAttr<TransparentUnionAttr>()) {
4718      for (RecordDecl::field_iterator it = UD->field_begin(),
4719           itend = UD->field_end(); it != itend; ++it) {
4720        QualType ET = it->getType();
4721        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
4722        if (!MT.isNull())
4723          return MT;
4724      }
4725    }
4726  }
4727
4728  return QualType();
4729}
4730
4731/// mergeFunctionArgumentTypes - merge two types which appear as function
4732/// argument types
4733QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
4734                                                bool OfBlockPointer,
4735                                                bool Unqualified) {
4736  // GNU extension: two types are compatible if they appear as a function
4737  // argument, one of the types is a transparent union type and the other
4738  // type is compatible with a union member
4739  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
4740                                              Unqualified);
4741  if (!lmerge.isNull())
4742    return lmerge;
4743
4744  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
4745                                              Unqualified);
4746  if (!rmerge.isNull())
4747    return rmerge;
4748
4749  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
4750}
4751
4752QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
4753                                        bool OfBlockPointer,
4754                                        bool Unqualified) {
4755  const FunctionType *lbase = lhs->getAs<FunctionType>();
4756  const FunctionType *rbase = rhs->getAs<FunctionType>();
4757  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
4758  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
4759  bool allLTypes = true;
4760  bool allRTypes = true;
4761
4762  // Check return type
4763  QualType retType;
4764  if (OfBlockPointer)
4765    retType = mergeTypes(rbase->getResultType(), lbase->getResultType(), true,
4766                         Unqualified);
4767  else
4768   retType = mergeTypes(lbase->getResultType(), rbase->getResultType(),
4769                        false, Unqualified);
4770  if (retType.isNull()) return QualType();
4771
4772  if (Unqualified)
4773    retType = retType.getUnqualifiedType();
4774
4775  CanQualType LRetType = getCanonicalType(lbase->getResultType());
4776  CanQualType RRetType = getCanonicalType(rbase->getResultType());
4777  if (Unqualified) {
4778    LRetType = LRetType.getUnqualifiedType();
4779    RRetType = RRetType.getUnqualifiedType();
4780  }
4781
4782  if (getCanonicalType(retType) != LRetType)
4783    allLTypes = false;
4784  if (getCanonicalType(retType) != RRetType)
4785    allRTypes = false;
4786  // FIXME: double check this
4787  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
4788  //                           rbase->getRegParmAttr() != 0 &&
4789  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
4790  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
4791  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
4792  unsigned RegParm = lbaseInfo.getRegParm() == 0 ? rbaseInfo.getRegParm() :
4793      lbaseInfo.getRegParm();
4794  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
4795  if (NoReturn != lbaseInfo.getNoReturn() ||
4796      RegParm != lbaseInfo.getRegParm())
4797    allLTypes = false;
4798  if (NoReturn != rbaseInfo.getNoReturn() ||
4799      RegParm != rbaseInfo.getRegParm())
4800    allRTypes = false;
4801  CallingConv lcc = lbaseInfo.getCC();
4802  CallingConv rcc = rbaseInfo.getCC();
4803  // Compatible functions must have compatible calling conventions
4804  if (!isSameCallConv(lcc, rcc))
4805    return QualType();
4806
4807  if (lproto && rproto) { // two C99 style function prototypes
4808    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
4809           "C++ shouldn't be here");
4810    unsigned lproto_nargs = lproto->getNumArgs();
4811    unsigned rproto_nargs = rproto->getNumArgs();
4812
4813    // Compatible functions must have the same number of arguments
4814    if (lproto_nargs != rproto_nargs)
4815      return QualType();
4816
4817    // Variadic and non-variadic functions aren't compatible
4818    if (lproto->isVariadic() != rproto->isVariadic())
4819      return QualType();
4820
4821    if (lproto->getTypeQuals() != rproto->getTypeQuals())
4822      return QualType();
4823
4824    // Check argument compatibility
4825    llvm::SmallVector<QualType, 10> types;
4826    for (unsigned i = 0; i < lproto_nargs; i++) {
4827      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
4828      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
4829      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
4830                                                    OfBlockPointer,
4831                                                    Unqualified);
4832      if (argtype.isNull()) return QualType();
4833
4834      if (Unqualified)
4835        argtype = argtype.getUnqualifiedType();
4836
4837      types.push_back(argtype);
4838      if (Unqualified) {
4839        largtype = largtype.getUnqualifiedType();
4840        rargtype = rargtype.getUnqualifiedType();
4841      }
4842
4843      if (getCanonicalType(argtype) != getCanonicalType(largtype))
4844        allLTypes = false;
4845      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
4846        allRTypes = false;
4847    }
4848    if (allLTypes) return lhs;
4849    if (allRTypes) return rhs;
4850    return getFunctionType(retType, types.begin(), types.size(),
4851                           lproto->isVariadic(), lproto->getTypeQuals(),
4852                           false, false, 0, 0,
4853                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4854  }
4855
4856  if (lproto) allRTypes = false;
4857  if (rproto) allLTypes = false;
4858
4859  const FunctionProtoType *proto = lproto ? lproto : rproto;
4860  if (proto) {
4861    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
4862    if (proto->isVariadic()) return QualType();
4863    // Check that the types are compatible with the types that
4864    // would result from default argument promotions (C99 6.7.5.3p15).
4865    // The only types actually affected are promotable integer
4866    // types and floats, which would be passed as a different
4867    // type depending on whether the prototype is visible.
4868    unsigned proto_nargs = proto->getNumArgs();
4869    for (unsigned i = 0; i < proto_nargs; ++i) {
4870      QualType argTy = proto->getArgType(i);
4871
4872      // Look at the promotion type of enum types, since that is the type used
4873      // to pass enum values.
4874      if (const EnumType *Enum = argTy->getAs<EnumType>())
4875        argTy = Enum->getDecl()->getPromotionType();
4876
4877      if (argTy->isPromotableIntegerType() ||
4878          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
4879        return QualType();
4880    }
4881
4882    if (allLTypes) return lhs;
4883    if (allRTypes) return rhs;
4884    return getFunctionType(retType, proto->arg_type_begin(),
4885                           proto->getNumArgs(), proto->isVariadic(),
4886                           proto->getTypeQuals(),
4887                           false, false, 0, 0,
4888                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4889  }
4890
4891  if (allLTypes) return lhs;
4892  if (allRTypes) return rhs;
4893  FunctionType::ExtInfo Info(NoReturn, RegParm, lcc);
4894  return getFunctionNoProtoType(retType, Info);
4895}
4896
4897QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
4898                                bool OfBlockPointer,
4899                                bool Unqualified) {
4900  // C++ [expr]: If an expression initially has the type "reference to T", the
4901  // type is adjusted to "T" prior to any further analysis, the expression
4902  // designates the object or function denoted by the reference, and the
4903  // expression is an lvalue unless the reference is an rvalue reference and
4904  // the expression is a function call (possibly inside parentheses).
4905  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
4906  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
4907
4908  if (Unqualified) {
4909    LHS = LHS.getUnqualifiedType();
4910    RHS = RHS.getUnqualifiedType();
4911  }
4912
4913  QualType LHSCan = getCanonicalType(LHS),
4914           RHSCan = getCanonicalType(RHS);
4915
4916  // If two types are identical, they are compatible.
4917  if (LHSCan == RHSCan)
4918    return LHS;
4919
4920  // If the qualifiers are different, the types aren't compatible... mostly.
4921  Qualifiers LQuals = LHSCan.getLocalQualifiers();
4922  Qualifiers RQuals = RHSCan.getLocalQualifiers();
4923  if (LQuals != RQuals) {
4924    // If any of these qualifiers are different, we have a type
4925    // mismatch.
4926    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
4927        LQuals.getAddressSpace() != RQuals.getAddressSpace())
4928      return QualType();
4929
4930    // Exactly one GC qualifier difference is allowed: __strong is
4931    // okay if the other type has no GC qualifier but is an Objective
4932    // C object pointer (i.e. implicitly strong by default).  We fix
4933    // this by pretending that the unqualified type was actually
4934    // qualified __strong.
4935    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
4936    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
4937    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
4938
4939    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
4940      return QualType();
4941
4942    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
4943      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
4944    }
4945    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
4946      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
4947    }
4948    return QualType();
4949  }
4950
4951  // Okay, qualifiers are equal.
4952
4953  Type::TypeClass LHSClass = LHSCan->getTypeClass();
4954  Type::TypeClass RHSClass = RHSCan->getTypeClass();
4955
4956  // We want to consider the two function types to be the same for these
4957  // comparisons, just force one to the other.
4958  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
4959  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
4960
4961  // Same as above for arrays
4962  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
4963    LHSClass = Type::ConstantArray;
4964  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
4965    RHSClass = Type::ConstantArray;
4966
4967  // ObjCInterfaces are just specialized ObjCObjects.
4968  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
4969  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
4970
4971  // Canonicalize ExtVector -> Vector.
4972  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
4973  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
4974
4975  // If the canonical type classes don't match.
4976  if (LHSClass != RHSClass) {
4977    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
4978    // a signed integer type, or an unsigned integer type.
4979    // Compatibility is based on the underlying type, not the promotion
4980    // type.
4981    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
4982      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
4983        return RHS;
4984    }
4985    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
4986      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
4987        return LHS;
4988    }
4989
4990    return QualType();
4991  }
4992
4993  // The canonical type classes match.
4994  switch (LHSClass) {
4995#define TYPE(Class, Base)
4996#define ABSTRACT_TYPE(Class, Base)
4997#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
4998#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
4999#define DEPENDENT_TYPE(Class, Base) case Type::Class:
5000#include "clang/AST/TypeNodes.def"
5001    assert(false && "Non-canonical and dependent types shouldn't get here");
5002    return QualType();
5003
5004  case Type::LValueReference:
5005  case Type::RValueReference:
5006  case Type::MemberPointer:
5007    assert(false && "C++ should never be in mergeTypes");
5008    return QualType();
5009
5010  case Type::ObjCInterface:
5011  case Type::IncompleteArray:
5012  case Type::VariableArray:
5013  case Type::FunctionProto:
5014  case Type::ExtVector:
5015    assert(false && "Types are eliminated above");
5016    return QualType();
5017
5018  case Type::Pointer:
5019  {
5020    // Merge two pointer types, while trying to preserve typedef info
5021    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
5022    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
5023    if (Unqualified) {
5024      LHSPointee = LHSPointee.getUnqualifiedType();
5025      RHSPointee = RHSPointee.getUnqualifiedType();
5026    }
5027    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
5028                                     Unqualified);
5029    if (ResultType.isNull()) return QualType();
5030    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5031      return LHS;
5032    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5033      return RHS;
5034    return getPointerType(ResultType);
5035  }
5036  case Type::BlockPointer:
5037  {
5038    // Merge two block pointer types, while trying to preserve typedef info
5039    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
5040    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
5041    if (Unqualified) {
5042      LHSPointee = LHSPointee.getUnqualifiedType();
5043      RHSPointee = RHSPointee.getUnqualifiedType();
5044    }
5045    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
5046                                     Unqualified);
5047    if (ResultType.isNull()) return QualType();
5048    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5049      return LHS;
5050    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5051      return RHS;
5052    return getBlockPointerType(ResultType);
5053  }
5054  case Type::ConstantArray:
5055  {
5056    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
5057    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
5058    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
5059      return QualType();
5060
5061    QualType LHSElem = getAsArrayType(LHS)->getElementType();
5062    QualType RHSElem = getAsArrayType(RHS)->getElementType();
5063    if (Unqualified) {
5064      LHSElem = LHSElem.getUnqualifiedType();
5065      RHSElem = RHSElem.getUnqualifiedType();
5066    }
5067
5068    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
5069    if (ResultType.isNull()) return QualType();
5070    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5071      return LHS;
5072    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5073      return RHS;
5074    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
5075                                          ArrayType::ArraySizeModifier(), 0);
5076    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
5077                                          ArrayType::ArraySizeModifier(), 0);
5078    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
5079    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
5080    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5081      return LHS;
5082    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5083      return RHS;
5084    if (LVAT) {
5085      // FIXME: This isn't correct! But tricky to implement because
5086      // the array's size has to be the size of LHS, but the type
5087      // has to be different.
5088      return LHS;
5089    }
5090    if (RVAT) {
5091      // FIXME: This isn't correct! But tricky to implement because
5092      // the array's size has to be the size of RHS, but the type
5093      // has to be different.
5094      return RHS;
5095    }
5096    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
5097    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
5098    return getIncompleteArrayType(ResultType,
5099                                  ArrayType::ArraySizeModifier(), 0);
5100  }
5101  case Type::FunctionNoProto:
5102    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
5103  case Type::Record:
5104  case Type::Enum:
5105    return QualType();
5106  case Type::Builtin:
5107    // Only exactly equal builtin types are compatible, which is tested above.
5108    return QualType();
5109  case Type::Complex:
5110    // Distinct complex types are incompatible.
5111    return QualType();
5112  case Type::Vector:
5113    // FIXME: The merged type should be an ExtVector!
5114    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
5115                             RHSCan->getAs<VectorType>()))
5116      return LHS;
5117    return QualType();
5118  case Type::ObjCObject: {
5119    // Check if the types are assignment compatible.
5120    // FIXME: This should be type compatibility, e.g. whether
5121    // "LHS x; RHS x;" at global scope is legal.
5122    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
5123    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
5124    if (canAssignObjCInterfaces(LHSIface, RHSIface))
5125      return LHS;
5126
5127    return QualType();
5128  }
5129  case Type::ObjCObjectPointer: {
5130    if (OfBlockPointer) {
5131      if (canAssignObjCInterfacesInBlockPointer(
5132                                          LHS->getAs<ObjCObjectPointerType>(),
5133                                          RHS->getAs<ObjCObjectPointerType>()))
5134      return LHS;
5135      return QualType();
5136    }
5137    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
5138                                RHS->getAs<ObjCObjectPointerType>()))
5139      return LHS;
5140
5141    return QualType();
5142    }
5143  }
5144
5145  return QualType();
5146}
5147
5148/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
5149/// 'RHS' attributes and returns the merged version; including for function
5150/// return types.
5151QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
5152  QualType LHSCan = getCanonicalType(LHS),
5153  RHSCan = getCanonicalType(RHS);
5154  // If two types are identical, they are compatible.
5155  if (LHSCan == RHSCan)
5156    return LHS;
5157  if (RHSCan->isFunctionType()) {
5158    if (!LHSCan->isFunctionType())
5159      return QualType();
5160    QualType OldReturnType =
5161      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
5162    QualType NewReturnType =
5163      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
5164    QualType ResReturnType =
5165      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
5166    if (ResReturnType.isNull())
5167      return QualType();
5168    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
5169      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
5170      // In either case, use OldReturnType to build the new function type.
5171      const FunctionType *F = LHS->getAs<FunctionType>();
5172      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
5173        FunctionType::ExtInfo Info = getFunctionExtInfo(LHS);
5174        QualType ResultType
5175          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
5176                                  FPT->getNumArgs(), FPT->isVariadic(),
5177                                  FPT->getTypeQuals(),
5178                                  FPT->hasExceptionSpec(),
5179                                  FPT->hasAnyExceptionSpec(),
5180                                  FPT->getNumExceptions(),
5181                                  FPT->exception_begin(),
5182                                  Info);
5183        return ResultType;
5184      }
5185    }
5186    return QualType();
5187  }
5188
5189  // If the qualifiers are different, the types can still be merged.
5190  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5191  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5192  if (LQuals != RQuals) {
5193    // If any of these qualifiers are different, we have a type mismatch.
5194    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5195        LQuals.getAddressSpace() != RQuals.getAddressSpace())
5196      return QualType();
5197
5198    // Exactly one GC qualifier difference is allowed: __strong is
5199    // okay if the other type has no GC qualifier but is an Objective
5200    // C object pointer (i.e. implicitly strong by default).  We fix
5201    // this by pretending that the unqualified type was actually
5202    // qualified __strong.
5203    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5204    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5205    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5206
5207    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5208      return QualType();
5209
5210    if (GC_L == Qualifiers::Strong)
5211      return LHS;
5212    if (GC_R == Qualifiers::Strong)
5213      return RHS;
5214    return QualType();
5215  }
5216
5217  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
5218    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5219    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5220    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
5221    if (ResQT == LHSBaseQT)
5222      return LHS;
5223    if (ResQT == RHSBaseQT)
5224      return RHS;
5225  }
5226  return QualType();
5227}
5228
5229//===----------------------------------------------------------------------===//
5230//                         Integer Predicates
5231//===----------------------------------------------------------------------===//
5232
5233unsigned ASTContext::getIntWidth(QualType T) {
5234  if (EnumType *ET = dyn_cast<EnumType>(T))
5235    T = ET->getDecl()->getIntegerType();
5236  if (T->isBooleanType())
5237    return 1;
5238  // For builtin types, just use the standard type sizing method
5239  return (unsigned)getTypeSize(T);
5240}
5241
5242QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
5243  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
5244
5245  // Turn <4 x signed int> -> <4 x unsigned int>
5246  if (const VectorType *VTy = T->getAs<VectorType>())
5247    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
5248             VTy->getNumElements(), VTy->getAltiVecSpecific());
5249
5250  // For enums, we return the unsigned version of the base type.
5251  if (const EnumType *ETy = T->getAs<EnumType>())
5252    T = ETy->getDecl()->getIntegerType();
5253
5254  const BuiltinType *BTy = T->getAs<BuiltinType>();
5255  assert(BTy && "Unexpected signed integer type");
5256  switch (BTy->getKind()) {
5257  case BuiltinType::Char_S:
5258  case BuiltinType::SChar:
5259    return UnsignedCharTy;
5260  case BuiltinType::Short:
5261    return UnsignedShortTy;
5262  case BuiltinType::Int:
5263    return UnsignedIntTy;
5264  case BuiltinType::Long:
5265    return UnsignedLongTy;
5266  case BuiltinType::LongLong:
5267    return UnsignedLongLongTy;
5268  case BuiltinType::Int128:
5269    return UnsignedInt128Ty;
5270  default:
5271    assert(0 && "Unexpected signed integer type");
5272    return QualType();
5273  }
5274}
5275
5276ExternalASTSource::~ExternalASTSource() { }
5277
5278void ExternalASTSource::PrintStats() { }
5279
5280ASTMutationListener::~ASTMutationListener() { }
5281
5282
5283//===----------------------------------------------------------------------===//
5284//                          Builtin Type Computation
5285//===----------------------------------------------------------------------===//
5286
5287/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
5288/// pointer over the consumed characters.  This returns the resultant type.  If
5289/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
5290/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
5291/// a vector of "i*".
5292///
5293/// RequiresICE is filled in on return to indicate whether the value is required
5294/// to be an Integer Constant Expression.
5295static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
5296                                  ASTContext::GetBuiltinTypeError &Error,
5297                                  bool &RequiresICE,
5298                                  bool AllowTypeModifiers) {
5299  // Modifiers.
5300  int HowLong = 0;
5301  bool Signed = false, Unsigned = false;
5302  RequiresICE = false;
5303
5304  // Read the prefixed modifiers first.
5305  bool Done = false;
5306  while (!Done) {
5307    switch (*Str++) {
5308    default: Done = true; --Str; break;
5309    case 'I':
5310      RequiresICE = true;
5311      break;
5312    case 'S':
5313      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
5314      assert(!Signed && "Can't use 'S' modifier multiple times!");
5315      Signed = true;
5316      break;
5317    case 'U':
5318      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
5319      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
5320      Unsigned = true;
5321      break;
5322    case 'L':
5323      assert(HowLong <= 2 && "Can't have LLLL modifier");
5324      ++HowLong;
5325      break;
5326    }
5327  }
5328
5329  QualType Type;
5330
5331  // Read the base type.
5332  switch (*Str++) {
5333  default: assert(0 && "Unknown builtin type letter!");
5334  case 'v':
5335    assert(HowLong == 0 && !Signed && !Unsigned &&
5336           "Bad modifiers used with 'v'!");
5337    Type = Context.VoidTy;
5338    break;
5339  case 'f':
5340    assert(HowLong == 0 && !Signed && !Unsigned &&
5341           "Bad modifiers used with 'f'!");
5342    Type = Context.FloatTy;
5343    break;
5344  case 'd':
5345    assert(HowLong < 2 && !Signed && !Unsigned &&
5346           "Bad modifiers used with 'd'!");
5347    if (HowLong)
5348      Type = Context.LongDoubleTy;
5349    else
5350      Type = Context.DoubleTy;
5351    break;
5352  case 's':
5353    assert(HowLong == 0 && "Bad modifiers used with 's'!");
5354    if (Unsigned)
5355      Type = Context.UnsignedShortTy;
5356    else
5357      Type = Context.ShortTy;
5358    break;
5359  case 'i':
5360    if (HowLong == 3)
5361      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
5362    else if (HowLong == 2)
5363      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
5364    else if (HowLong == 1)
5365      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
5366    else
5367      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
5368    break;
5369  case 'c':
5370    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
5371    if (Signed)
5372      Type = Context.SignedCharTy;
5373    else if (Unsigned)
5374      Type = Context.UnsignedCharTy;
5375    else
5376      Type = Context.CharTy;
5377    break;
5378  case 'b': // boolean
5379    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
5380    Type = Context.BoolTy;
5381    break;
5382  case 'z':  // size_t.
5383    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
5384    Type = Context.getSizeType();
5385    break;
5386  case 'F':
5387    Type = Context.getCFConstantStringType();
5388    break;
5389  case 'a':
5390    Type = Context.getBuiltinVaListType();
5391    assert(!Type.isNull() && "builtin va list type not initialized!");
5392    break;
5393  case 'A':
5394    // This is a "reference" to a va_list; however, what exactly
5395    // this means depends on how va_list is defined. There are two
5396    // different kinds of va_list: ones passed by value, and ones
5397    // passed by reference.  An example of a by-value va_list is
5398    // x86, where va_list is a char*. An example of by-ref va_list
5399    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
5400    // we want this argument to be a char*&; for x86-64, we want
5401    // it to be a __va_list_tag*.
5402    Type = Context.getBuiltinVaListType();
5403    assert(!Type.isNull() && "builtin va list type not initialized!");
5404    if (Type->isArrayType())
5405      Type = Context.getArrayDecayedType(Type);
5406    else
5407      Type = Context.getLValueReferenceType(Type);
5408    break;
5409  case 'V': {
5410    char *End;
5411    unsigned NumElements = strtoul(Str, &End, 10);
5412    assert(End != Str && "Missing vector size");
5413    Str = End;
5414
5415    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
5416                                             RequiresICE, false);
5417    assert(!RequiresICE && "Can't require vector ICE");
5418
5419    // TODO: No way to make AltiVec vectors in builtins yet.
5420    Type = Context.getVectorType(ElementType, NumElements,
5421                                 VectorType::NotAltiVec);
5422    break;
5423  }
5424  case 'X': {
5425    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
5426                                             false);
5427    assert(!RequiresICE && "Can't require complex ICE");
5428    Type = Context.getComplexType(ElementType);
5429    break;
5430  }
5431  case 'P':
5432    Type = Context.getFILEType();
5433    if (Type.isNull()) {
5434      Error = ASTContext::GE_Missing_stdio;
5435      return QualType();
5436    }
5437    break;
5438  case 'J':
5439    if (Signed)
5440      Type = Context.getsigjmp_bufType();
5441    else
5442      Type = Context.getjmp_bufType();
5443
5444    if (Type.isNull()) {
5445      Error = ASTContext::GE_Missing_setjmp;
5446      return QualType();
5447    }
5448    break;
5449  }
5450
5451  // If there are modifiers and if we're allowed to parse them, go for it.
5452  Done = !AllowTypeModifiers;
5453  while (!Done) {
5454    switch (char c = *Str++) {
5455    default: Done = true; --Str; break;
5456    case '*':
5457    case '&': {
5458      // Both pointers and references can have their pointee types
5459      // qualified with an address space.
5460      char *End;
5461      unsigned AddrSpace = strtoul(Str, &End, 10);
5462      if (End != Str && AddrSpace != 0) {
5463        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
5464        Str = End;
5465      }
5466      if (c == '*')
5467        Type = Context.getPointerType(Type);
5468      else
5469        Type = Context.getLValueReferenceType(Type);
5470      break;
5471    }
5472    // FIXME: There's no way to have a built-in with an rvalue ref arg.
5473    case 'C':
5474      Type = Type.withConst();
5475      break;
5476    case 'D':
5477      Type = Context.getVolatileType(Type);
5478      break;
5479    }
5480  }
5481
5482  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
5483         "Integer constant 'I' type must be an integer");
5484
5485  return Type;
5486}
5487
5488/// GetBuiltinType - Return the type for the specified builtin.
5489QualType ASTContext::GetBuiltinType(unsigned Id,
5490                                    GetBuiltinTypeError &Error,
5491                                    unsigned *IntegerConstantArgs) {
5492  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
5493
5494  llvm::SmallVector<QualType, 8> ArgTypes;
5495
5496  bool RequiresICE = false;
5497  Error = GE_None;
5498  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
5499                                       RequiresICE, true);
5500  if (Error != GE_None)
5501    return QualType();
5502
5503  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
5504
5505  while (TypeStr[0] && TypeStr[0] != '.') {
5506    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
5507    if (Error != GE_None)
5508      return QualType();
5509
5510    // If this argument is required to be an IntegerConstantExpression and the
5511    // caller cares, fill in the bitmask we return.
5512    if (RequiresICE && IntegerConstantArgs)
5513      *IntegerConstantArgs |= 1 << ArgTypes.size();
5514
5515    // Do array -> pointer decay.  The builtin should use the decayed type.
5516    if (Ty->isArrayType())
5517      Ty = getArrayDecayedType(Ty);
5518
5519    ArgTypes.push_back(Ty);
5520  }
5521
5522  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
5523         "'.' should only occur at end of builtin type list!");
5524
5525  // handle untyped/variadic arguments "T c99Style();" or "T cppStyle(...);".
5526  if (ArgTypes.size() == 0 && TypeStr[0] == '.')
5527    return getFunctionNoProtoType(ResType);
5528
5529  // FIXME: Should we create noreturn types?
5530  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(),
5531                         TypeStr[0] == '.', 0, false, false, 0, 0,
5532                         FunctionType::ExtInfo());
5533}
5534
5535QualType
5536ASTContext::UsualArithmeticConversionsType(QualType lhs, QualType rhs) {
5537  // Perform the usual unary conversions. We do this early so that
5538  // integral promotions to "int" can allow us to exit early, in the
5539  // lhs == rhs check. Also, for conversion purposes, we ignore any
5540  // qualifiers.  For example, "const float" and "float" are
5541  // equivalent.
5542  if (lhs->isPromotableIntegerType())
5543    lhs = getPromotedIntegerType(lhs);
5544  else
5545    lhs = lhs.getUnqualifiedType();
5546  if (rhs->isPromotableIntegerType())
5547    rhs = getPromotedIntegerType(rhs);
5548  else
5549    rhs = rhs.getUnqualifiedType();
5550
5551  // If both types are identical, no conversion is needed.
5552  if (lhs == rhs)
5553    return lhs;
5554
5555  // If either side is a non-arithmetic type (e.g. a pointer), we are done.
5556  // The caller can deal with this (e.g. pointer + int).
5557  if (!lhs->isArithmeticType() || !rhs->isArithmeticType())
5558    return lhs;
5559
5560  // At this point, we have two different arithmetic types.
5561
5562  // Handle complex types first (C99 6.3.1.8p1).
5563  if (lhs->isComplexType() || rhs->isComplexType()) {
5564    // if we have an integer operand, the result is the complex type.
5565    if (rhs->isIntegerType() || rhs->isComplexIntegerType()) {
5566      // convert the rhs to the lhs complex type.
5567      return lhs;
5568    }
5569    if (lhs->isIntegerType() || lhs->isComplexIntegerType()) {
5570      // convert the lhs to the rhs complex type.
5571      return rhs;
5572    }
5573    // This handles complex/complex, complex/float, or float/complex.
5574    // When both operands are complex, the shorter operand is converted to the
5575    // type of the longer, and that is the type of the result. This corresponds
5576    // to what is done when combining two real floating-point operands.
5577    // The fun begins when size promotion occur across type domains.
5578    // From H&S 6.3.4: When one operand is complex and the other is a real
5579    // floating-point type, the less precise type is converted, within it's
5580    // real or complex domain, to the precision of the other type. For example,
5581    // when combining a "long double" with a "double _Complex", the
5582    // "double _Complex" is promoted to "long double _Complex".
5583    int result = getFloatingTypeOrder(lhs, rhs);
5584
5585    if (result > 0) { // The left side is bigger, convert rhs.
5586      rhs = getFloatingTypeOfSizeWithinDomain(lhs, rhs);
5587    } else if (result < 0) { // The right side is bigger, convert lhs.
5588      lhs = getFloatingTypeOfSizeWithinDomain(rhs, lhs);
5589    }
5590    // At this point, lhs and rhs have the same rank/size. Now, make sure the
5591    // domains match. This is a requirement for our implementation, C99
5592    // does not require this promotion.
5593    if (lhs != rhs) { // Domains don't match, we have complex/float mix.
5594      if (lhs->isRealFloatingType()) { // handle "double, _Complex double".
5595        return rhs;
5596      } else { // handle "_Complex double, double".
5597        return lhs;
5598      }
5599    }
5600    return lhs; // The domain/size match exactly.
5601  }
5602  // Now handle "real" floating types (i.e. float, double, long double).
5603  if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) {
5604    // if we have an integer operand, the result is the real floating type.
5605    if (rhs->isIntegerType()) {
5606      // convert rhs to the lhs floating point type.
5607      return lhs;
5608    }
5609    if (rhs->isComplexIntegerType()) {
5610      // convert rhs to the complex floating point type.
5611      return getComplexType(lhs);
5612    }
5613    if (lhs->isIntegerType()) {
5614      // convert lhs to the rhs floating point type.
5615      return rhs;
5616    }
5617    if (lhs->isComplexIntegerType()) {
5618      // convert lhs to the complex floating point type.
5619      return getComplexType(rhs);
5620    }
5621    // We have two real floating types, float/complex combos were handled above.
5622    // Convert the smaller operand to the bigger result.
5623    int result = getFloatingTypeOrder(lhs, rhs);
5624    if (result > 0) // convert the rhs
5625      return lhs;
5626    assert(result < 0 && "illegal float comparison");
5627    return rhs;   // convert the lhs
5628  }
5629  if (lhs->isComplexIntegerType() || rhs->isComplexIntegerType()) {
5630    // Handle GCC complex int extension.
5631    const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType();
5632    const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType();
5633
5634    if (lhsComplexInt && rhsComplexInt) {
5635      if (getIntegerTypeOrder(lhsComplexInt->getElementType(),
5636                              rhsComplexInt->getElementType()) >= 0)
5637        return lhs; // convert the rhs
5638      return rhs;
5639    } else if (lhsComplexInt && rhs->isIntegerType()) {
5640      // convert the rhs to the lhs complex type.
5641      return lhs;
5642    } else if (rhsComplexInt && lhs->isIntegerType()) {
5643      // convert the lhs to the rhs complex type.
5644      return rhs;
5645    }
5646  }
5647  // Finally, we have two differing integer types.
5648  // The rules for this case are in C99 6.3.1.8
5649  int compare = getIntegerTypeOrder(lhs, rhs);
5650  bool lhsSigned = lhs->hasSignedIntegerRepresentation(),
5651       rhsSigned = rhs->hasSignedIntegerRepresentation();
5652  QualType destType;
5653  if (lhsSigned == rhsSigned) {
5654    // Same signedness; use the higher-ranked type
5655    destType = compare >= 0 ? lhs : rhs;
5656  } else if (compare != (lhsSigned ? 1 : -1)) {
5657    // The unsigned type has greater than or equal rank to the
5658    // signed type, so use the unsigned type
5659    destType = lhsSigned ? rhs : lhs;
5660  } else if (getIntWidth(lhs) != getIntWidth(rhs)) {
5661    // The two types are different widths; if we are here, that
5662    // means the signed type is larger than the unsigned type, so
5663    // use the signed type.
5664    destType = lhsSigned ? lhs : rhs;
5665  } else {
5666    // The signed type is higher-ranked than the unsigned type,
5667    // but isn't actually any bigger (like unsigned int and long
5668    // on most 32-bit systems).  Use the unsigned type corresponding
5669    // to the signed type.
5670    destType = getCorrespondingUnsignedType(lhsSigned ? lhs : rhs);
5671  }
5672  return destType;
5673}
5674
5675GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
5676  GVALinkage External = GVA_StrongExternal;
5677
5678  Linkage L = FD->getLinkage();
5679  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5680      FD->getType()->getLinkage() == UniqueExternalLinkage)
5681    L = UniqueExternalLinkage;
5682
5683  switch (L) {
5684  case NoLinkage:
5685  case InternalLinkage:
5686  case UniqueExternalLinkage:
5687    return GVA_Internal;
5688
5689  case ExternalLinkage:
5690    switch (FD->getTemplateSpecializationKind()) {
5691    case TSK_Undeclared:
5692    case TSK_ExplicitSpecialization:
5693      External = GVA_StrongExternal;
5694      break;
5695
5696    case TSK_ExplicitInstantiationDefinition:
5697      return GVA_ExplicitTemplateInstantiation;
5698
5699    case TSK_ExplicitInstantiationDeclaration:
5700    case TSK_ImplicitInstantiation:
5701      External = GVA_TemplateInstantiation;
5702      break;
5703    }
5704  }
5705
5706  if (!FD->isInlined())
5707    return External;
5708
5709  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
5710    // GNU or C99 inline semantics. Determine whether this symbol should be
5711    // externally visible.
5712    if (FD->isInlineDefinitionExternallyVisible())
5713      return External;
5714
5715    // C99 inline semantics, where the symbol is not externally visible.
5716    return GVA_C99Inline;
5717  }
5718
5719  // C++0x [temp.explicit]p9:
5720  //   [ Note: The intent is that an inline function that is the subject of
5721  //   an explicit instantiation declaration will still be implicitly
5722  //   instantiated when used so that the body can be considered for
5723  //   inlining, but that no out-of-line copy of the inline function would be
5724  //   generated in the translation unit. -- end note ]
5725  if (FD->getTemplateSpecializationKind()
5726                                       == TSK_ExplicitInstantiationDeclaration)
5727    return GVA_C99Inline;
5728
5729  return GVA_CXXInline;
5730}
5731
5732GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
5733  // If this is a static data member, compute the kind of template
5734  // specialization. Otherwise, this variable is not part of a
5735  // template.
5736  TemplateSpecializationKind TSK = TSK_Undeclared;
5737  if (VD->isStaticDataMember())
5738    TSK = VD->getTemplateSpecializationKind();
5739
5740  Linkage L = VD->getLinkage();
5741  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5742      VD->getType()->getLinkage() == UniqueExternalLinkage)
5743    L = UniqueExternalLinkage;
5744
5745  switch (L) {
5746  case NoLinkage:
5747  case InternalLinkage:
5748  case UniqueExternalLinkage:
5749    return GVA_Internal;
5750
5751  case ExternalLinkage:
5752    switch (TSK) {
5753    case TSK_Undeclared:
5754    case TSK_ExplicitSpecialization:
5755      return GVA_StrongExternal;
5756
5757    case TSK_ExplicitInstantiationDeclaration:
5758      llvm_unreachable("Variable should not be instantiated");
5759      // Fall through to treat this like any other instantiation.
5760
5761    case TSK_ExplicitInstantiationDefinition:
5762      return GVA_ExplicitTemplateInstantiation;
5763
5764    case TSK_ImplicitInstantiation:
5765      return GVA_TemplateInstantiation;
5766    }
5767  }
5768
5769  return GVA_StrongExternal;
5770}
5771
5772bool ASTContext::DeclMustBeEmitted(const Decl *D) {
5773  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
5774    if (!VD->isFileVarDecl())
5775      return false;
5776  } else if (!isa<FunctionDecl>(D))
5777    return false;
5778
5779  // Weak references don't produce any output by themselves.
5780  if (D->hasAttr<WeakRefAttr>())
5781    return false;
5782
5783  // Aliases and used decls are required.
5784  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
5785    return true;
5786
5787  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
5788    // Forward declarations aren't required.
5789    if (!FD->isThisDeclarationADefinition())
5790      return false;
5791
5792    // Constructors and destructors are required.
5793    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
5794      return true;
5795
5796    // The key function for a class is required.
5797    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
5798      const CXXRecordDecl *RD = MD->getParent();
5799      if (MD->isOutOfLine() && RD->isDynamicClass()) {
5800        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
5801        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
5802          return true;
5803      }
5804    }
5805
5806    GVALinkage Linkage = GetGVALinkageForFunction(FD);
5807
5808    // static, static inline, always_inline, and extern inline functions can
5809    // always be deferred.  Normal inline functions can be deferred in C99/C++.
5810    // Implicit template instantiations can also be deferred in C++.
5811    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
5812        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
5813      return false;
5814    return true;
5815  }
5816
5817  const VarDecl *VD = cast<VarDecl>(D);
5818  assert(VD->isFileVarDecl() && "Expected file scoped var");
5819
5820  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
5821    return false;
5822
5823  // Structs that have non-trivial constructors or destructors are required.
5824
5825  // FIXME: Handle references.
5826  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
5827    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
5828      if (RD->hasDefinition() &&
5829          (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()))
5830        return true;
5831    }
5832  }
5833
5834  GVALinkage L = GetGVALinkageForVariable(VD);
5835  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
5836    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
5837      return false;
5838  }
5839
5840  return true;
5841}
5842
5843CXXABI::~CXXABI() {}
5844