ASTContext.cpp revision 32adc8bd6f05d1e26cc221102e48609da2c446ba 
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), 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    if (NumElts)
1496      NumElts->Retain();
1497    CanonType = getVariableArrayType(getCanonicalType(EltTy), NumElts, ASM,
1498                                     EltTypeQuals, Brackets);
1499  }
1500
1501  VariableArrayType *New = new(*this, TypeAlignment)
1502    VariableArrayType(EltTy, CanonType, NumElts, ASM, EltTypeQuals, Brackets);
1503
1504  VariableArrayTypes.push_back(New);
1505  Types.push_back(New);
1506  return QualType(New, 0);
1507}
1508
1509/// getDependentSizedArrayType - Returns a non-unique reference to
1510/// the type for a dependently-sized array of the specified element
1511/// type.
1512QualType ASTContext::getDependentSizedArrayType(QualType EltTy,
1513                                                Expr *NumElts,
1514                                                ArrayType::ArraySizeModifier ASM,
1515                                                unsigned EltTypeQuals,
1516                                                SourceRange Brackets) {
1517  assert((!NumElts || NumElts->isTypeDependent() ||
1518          NumElts->isValueDependent()) &&
1519         "Size must be type- or value-dependent!");
1520
1521  void *InsertPos = 0;
1522  DependentSizedArrayType *Canon = 0;
1523  llvm::FoldingSetNodeID ID;
1524
1525  QualType CanonicalEltTy = getCanonicalType(EltTy);
1526  if (NumElts) {
1527    // Dependently-sized array types that do not have a specified
1528    // number of elements will have their sizes deduced from an
1529    // initializer.
1530    DependentSizedArrayType::Profile(ID, *this, CanonicalEltTy, ASM,
1531                                     EltTypeQuals, NumElts);
1532
1533    Canon = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1534  }
1535
1536  DependentSizedArrayType *New;
1537  if (Canon) {
1538    // We already have a canonical version of this array type; use it as
1539    // the canonical type for a newly-built type.
1540    New = new (*this, TypeAlignment)
1541      DependentSizedArrayType(*this, EltTy, QualType(Canon, 0),
1542                              NumElts, ASM, EltTypeQuals, Brackets);
1543  } else if (CanonicalEltTy == EltTy) {
1544    // This is a canonical type. Record it.
1545    New = new (*this, TypeAlignment)
1546      DependentSizedArrayType(*this, EltTy, QualType(),
1547                              NumElts, ASM, EltTypeQuals, Brackets);
1548
1549    if (NumElts) {
1550#ifndef NDEBUG
1551      DependentSizedArrayType *CanonCheck
1552        = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1553      assert(!CanonCheck && "Dependent-sized canonical array type broken");
1554      (void)CanonCheck;
1555#endif
1556      DependentSizedArrayTypes.InsertNode(New, InsertPos);
1557    }
1558  } else {
1559    QualType Canon = getDependentSizedArrayType(CanonicalEltTy, NumElts,
1560                                                ASM, EltTypeQuals,
1561                                                SourceRange());
1562    New = new (*this, TypeAlignment)
1563      DependentSizedArrayType(*this, EltTy, Canon,
1564                              NumElts, ASM, EltTypeQuals, Brackets);
1565  }
1566
1567  Types.push_back(New);
1568  return QualType(New, 0);
1569}
1570
1571QualType ASTContext::getIncompleteArrayType(QualType EltTy,
1572                                            ArrayType::ArraySizeModifier ASM,
1573                                            unsigned EltTypeQuals) {
1574  llvm::FoldingSetNodeID ID;
1575  IncompleteArrayType::Profile(ID, EltTy, ASM, EltTypeQuals);
1576
1577  void *InsertPos = 0;
1578  if (IncompleteArrayType *ATP =
1579       IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1580    return QualType(ATP, 0);
1581
1582  // If the element type isn't canonical, this won't be a canonical type
1583  // either, so fill in the canonical type field.
1584  QualType Canonical;
1585
1586  if (!EltTy.isCanonical()) {
1587    Canonical = getIncompleteArrayType(getCanonicalType(EltTy),
1588                                       ASM, EltTypeQuals);
1589
1590    // Get the new insert position for the node we care about.
1591    IncompleteArrayType *NewIP =
1592      IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1593    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1594  }
1595
1596  IncompleteArrayType *New = new (*this, TypeAlignment)
1597    IncompleteArrayType(EltTy, Canonical, ASM, EltTypeQuals);
1598
1599  IncompleteArrayTypes.InsertNode(New, InsertPos);
1600  Types.push_back(New);
1601  return QualType(New, 0);
1602}
1603
1604/// getVectorType - Return the unique reference to a vector type of
1605/// the specified element type and size. VectorType must be a built-in type.
1606QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1607                                   VectorType::AltiVecSpecific AltiVecSpec) {
1608  BuiltinType *BaseType;
1609
1610  BaseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1611  assert(BaseType != 0 && "getVectorType(): Expecting a built-in type");
1612
1613  // Check if we've already instantiated a vector of this type.
1614  llvm::FoldingSetNodeID ID;
1615  VectorType::Profile(ID, vecType, NumElts, Type::Vector, AltiVecSpec);
1616
1617  void *InsertPos = 0;
1618  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1619    return QualType(VTP, 0);
1620
1621  // If the element type isn't canonical, this won't be a canonical type either,
1622  // so fill in the canonical type field.
1623  QualType Canonical;
1624  if (!vecType.isCanonical()) {
1625    Canonical = getVectorType(getCanonicalType(vecType), NumElts,
1626      VectorType::NotAltiVec);
1627
1628    // Get the new insert position for the node we care about.
1629    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1630    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1631  }
1632  VectorType *New = new (*this, TypeAlignment)
1633    VectorType(vecType, NumElts, Canonical, AltiVecSpec);
1634  VectorTypes.InsertNode(New, InsertPos);
1635  Types.push_back(New);
1636  return QualType(New, 0);
1637}
1638
1639/// getExtVectorType - Return the unique reference to an extended vector type of
1640/// the specified element type and size. VectorType must be a built-in type.
1641QualType ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) {
1642  BuiltinType *baseType;
1643
1644  baseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1645  assert(baseType != 0 && "getExtVectorType(): Expecting a built-in type");
1646
1647  // Check if we've already instantiated a vector of this type.
1648  llvm::FoldingSetNodeID ID;
1649  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1650                      VectorType::NotAltiVec);
1651  void *InsertPos = 0;
1652  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1653    return QualType(VTP, 0);
1654
1655  // If the element type isn't canonical, this won't be a canonical type either,
1656  // so fill in the canonical type field.
1657  QualType Canonical;
1658  if (!vecType.isCanonical()) {
1659    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
1660
1661    // Get the new insert position for the node we care about.
1662    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1663    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1664  }
1665  ExtVectorType *New = new (*this, TypeAlignment)
1666    ExtVectorType(vecType, NumElts, Canonical);
1667  VectorTypes.InsertNode(New, InsertPos);
1668  Types.push_back(New);
1669  return QualType(New, 0);
1670}
1671
1672QualType ASTContext::getDependentSizedExtVectorType(QualType vecType,
1673                                                    Expr *SizeExpr,
1674                                                    SourceLocation AttrLoc) {
1675  llvm::FoldingSetNodeID ID;
1676  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
1677                                       SizeExpr);
1678
1679  void *InsertPos = 0;
1680  DependentSizedExtVectorType *Canon
1681    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1682  DependentSizedExtVectorType *New;
1683  if (Canon) {
1684    // We already have a canonical version of this array type; use it as
1685    // the canonical type for a newly-built type.
1686    New = new (*this, TypeAlignment)
1687      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
1688                                  SizeExpr, AttrLoc);
1689  } else {
1690    QualType CanonVecTy = getCanonicalType(vecType);
1691    if (CanonVecTy == vecType) {
1692      New = new (*this, TypeAlignment)
1693        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
1694                                    AttrLoc);
1695
1696      DependentSizedExtVectorType *CanonCheck
1697        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1698      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
1699      (void)CanonCheck;
1700      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
1701    } else {
1702      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
1703                                                      SourceLocation());
1704      New = new (*this, TypeAlignment)
1705        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
1706    }
1707  }
1708
1709  Types.push_back(New);
1710  return QualType(New, 0);
1711}
1712
1713/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
1714///
1715QualType ASTContext::getFunctionNoProtoType(QualType ResultTy,
1716                                            const FunctionType::ExtInfo &Info) {
1717  const CallingConv CallConv = Info.getCC();
1718  // Unique functions, to guarantee there is only one function of a particular
1719  // structure.
1720  llvm::FoldingSetNodeID ID;
1721  FunctionNoProtoType::Profile(ID, ResultTy, Info);
1722
1723  void *InsertPos = 0;
1724  if (FunctionNoProtoType *FT =
1725        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1726    return QualType(FT, 0);
1727
1728  QualType Canonical;
1729  if (!ResultTy.isCanonical() ||
1730      getCanonicalCallConv(CallConv) != CallConv) {
1731    Canonical =
1732      getFunctionNoProtoType(getCanonicalType(ResultTy),
1733                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1734
1735    // Get the new insert position for the node we care about.
1736    FunctionNoProtoType *NewIP =
1737      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1738    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1739  }
1740
1741  FunctionNoProtoType *New = new (*this, TypeAlignment)
1742    FunctionNoProtoType(ResultTy, Canonical, Info);
1743  Types.push_back(New);
1744  FunctionNoProtoTypes.InsertNode(New, InsertPos);
1745  return QualType(New, 0);
1746}
1747
1748/// getFunctionType - Return a normal function type with a typed argument
1749/// list.  isVariadic indicates whether the argument list includes '...'.
1750QualType ASTContext::getFunctionType(QualType ResultTy,const QualType *ArgArray,
1751                                     unsigned NumArgs, bool isVariadic,
1752                                     unsigned TypeQuals, bool hasExceptionSpec,
1753                                     bool hasAnyExceptionSpec, unsigned NumExs,
1754                                     const QualType *ExArray,
1755                                     const FunctionType::ExtInfo &Info) {
1756
1757  const CallingConv CallConv= Info.getCC();
1758  // Unique functions, to guarantee there is only one function of a particular
1759  // structure.
1760  llvm::FoldingSetNodeID ID;
1761  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, isVariadic,
1762                             TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1763                             NumExs, ExArray, Info);
1764
1765  void *InsertPos = 0;
1766  if (FunctionProtoType *FTP =
1767        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1768    return QualType(FTP, 0);
1769
1770  // Determine whether the type being created is already canonical or not.
1771  bool isCanonical = !hasExceptionSpec && ResultTy.isCanonical();
1772  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
1773    if (!ArgArray[i].isCanonicalAsParam())
1774      isCanonical = false;
1775
1776  // If this type isn't canonical, get the canonical version of it.
1777  // The exception spec is not part of the canonical type.
1778  QualType Canonical;
1779  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
1780    llvm::SmallVector<QualType, 16> CanonicalArgs;
1781    CanonicalArgs.reserve(NumArgs);
1782    for (unsigned i = 0; i != NumArgs; ++i)
1783      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
1784
1785    Canonical = getFunctionType(getCanonicalType(ResultTy),
1786                                CanonicalArgs.data(), NumArgs,
1787                                isVariadic, TypeQuals, false,
1788                                false, 0, 0,
1789                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1790
1791    // Get the new insert position for the node we care about.
1792    FunctionProtoType *NewIP =
1793      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1794    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1795  }
1796
1797  // FunctionProtoType objects are allocated with extra bytes after them
1798  // for two variable size arrays (for parameter and exception types) at the
1799  // end of them.
1800  FunctionProtoType *FTP =
1801    (FunctionProtoType*)Allocate(sizeof(FunctionProtoType) +
1802                                 NumArgs*sizeof(QualType) +
1803                                 NumExs*sizeof(QualType), TypeAlignment);
1804  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, isVariadic,
1805                              TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1806                              ExArray, NumExs, Canonical, Info);
1807  Types.push_back(FTP);
1808  FunctionProtoTypes.InsertNode(FTP, InsertPos);
1809  return QualType(FTP, 0);
1810}
1811
1812#ifndef NDEBUG
1813static bool NeedsInjectedClassNameType(const RecordDecl *D) {
1814  if (!isa<CXXRecordDecl>(D)) return false;
1815  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
1816  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
1817    return true;
1818  if (RD->getDescribedClassTemplate() &&
1819      !isa<ClassTemplateSpecializationDecl>(RD))
1820    return true;
1821  return false;
1822}
1823#endif
1824
1825/// getInjectedClassNameType - Return the unique reference to the
1826/// injected class name type for the specified templated declaration.
1827QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
1828                                              QualType TST) {
1829  assert(NeedsInjectedClassNameType(Decl));
1830  if (Decl->TypeForDecl) {
1831    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1832  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDeclaration()) {
1833    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
1834    Decl->TypeForDecl = PrevDecl->TypeForDecl;
1835    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1836  } else {
1837    Decl->TypeForDecl =
1838      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
1839    Types.push_back(Decl->TypeForDecl);
1840  }
1841  return QualType(Decl->TypeForDecl, 0);
1842}
1843
1844/// getTypeDeclType - Return the unique reference to the type for the
1845/// specified type declaration.
1846QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) {
1847  assert(Decl && "Passed null for Decl param");
1848  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
1849
1850  if (const TypedefDecl *Typedef = dyn_cast<TypedefDecl>(Decl))
1851    return getTypedefType(Typedef);
1852
1853  assert(!isa<TemplateTypeParmDecl>(Decl) &&
1854         "Template type parameter types are always available.");
1855
1856  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
1857    assert(!Record->getPreviousDeclaration() &&
1858           "struct/union has previous declaration");
1859    assert(!NeedsInjectedClassNameType(Record));
1860    return getRecordType(Record);
1861  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
1862    assert(!Enum->getPreviousDeclaration() &&
1863           "enum has previous declaration");
1864    return getEnumType(Enum);
1865  } else if (const UnresolvedUsingTypenameDecl *Using =
1866               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
1867    Decl->TypeForDecl = new (*this, TypeAlignment) UnresolvedUsingType(Using);
1868  } else
1869    llvm_unreachable("TypeDecl without a type?");
1870
1871  Types.push_back(Decl->TypeForDecl);
1872  return QualType(Decl->TypeForDecl, 0);
1873}
1874
1875/// getTypedefType - Return the unique reference to the type for the
1876/// specified typename decl.
1877QualType
1878ASTContext::getTypedefType(const TypedefDecl *Decl, QualType Canonical) {
1879  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1880
1881  if (Canonical.isNull())
1882    Canonical = getCanonicalType(Decl->getUnderlyingType());
1883  Decl->TypeForDecl = new(*this, TypeAlignment)
1884    TypedefType(Type::Typedef, Decl, Canonical);
1885  Types.push_back(Decl->TypeForDecl);
1886  return QualType(Decl->TypeForDecl, 0);
1887}
1888
1889QualType ASTContext::getRecordType(const RecordDecl *Decl) {
1890  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1891
1892  if (const RecordDecl *PrevDecl = Decl->getPreviousDeclaration())
1893    if (PrevDecl->TypeForDecl)
1894      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1895
1896  Decl->TypeForDecl = new (*this, TypeAlignment) RecordType(Decl);
1897  Types.push_back(Decl->TypeForDecl);
1898  return QualType(Decl->TypeForDecl, 0);
1899}
1900
1901QualType ASTContext::getEnumType(const EnumDecl *Decl) {
1902  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1903
1904  if (const EnumDecl *PrevDecl = Decl->getPreviousDeclaration())
1905    if (PrevDecl->TypeForDecl)
1906      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1907
1908  Decl->TypeForDecl = new (*this, TypeAlignment) EnumType(Decl);
1909  Types.push_back(Decl->TypeForDecl);
1910  return QualType(Decl->TypeForDecl, 0);
1911}
1912
1913/// \brief Retrieve a substitution-result type.
1914QualType
1915ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
1916                                         QualType Replacement) {
1917  assert(Replacement.isCanonical()
1918         && "replacement types must always be canonical");
1919
1920  llvm::FoldingSetNodeID ID;
1921  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
1922  void *InsertPos = 0;
1923  SubstTemplateTypeParmType *SubstParm
1924    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1925
1926  if (!SubstParm) {
1927    SubstParm = new (*this, TypeAlignment)
1928      SubstTemplateTypeParmType(Parm, Replacement);
1929    Types.push_back(SubstParm);
1930    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
1931  }
1932
1933  return QualType(SubstParm, 0);
1934}
1935
1936/// \brief Retrieve the template type parameter type for a template
1937/// parameter or parameter pack with the given depth, index, and (optionally)
1938/// name.
1939QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
1940                                             bool ParameterPack,
1941                                             IdentifierInfo *Name) {
1942  llvm::FoldingSetNodeID ID;
1943  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, Name);
1944  void *InsertPos = 0;
1945  TemplateTypeParmType *TypeParm
1946    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1947
1948  if (TypeParm)
1949    return QualType(TypeParm, 0);
1950
1951  if (Name) {
1952    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
1953    TypeParm = new (*this, TypeAlignment)
1954      TemplateTypeParmType(Depth, Index, ParameterPack, Name, Canon);
1955
1956    TemplateTypeParmType *TypeCheck
1957      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1958    assert(!TypeCheck && "Template type parameter canonical type broken");
1959    (void)TypeCheck;
1960  } else
1961    TypeParm = new (*this, TypeAlignment)
1962      TemplateTypeParmType(Depth, Index, ParameterPack);
1963
1964  Types.push_back(TypeParm);
1965  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
1966
1967  return QualType(TypeParm, 0);
1968}
1969
1970TypeSourceInfo *
1971ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
1972                                              SourceLocation NameLoc,
1973                                        const TemplateArgumentListInfo &Args,
1974                                              QualType CanonType) {
1975  QualType TST = getTemplateSpecializationType(Name, Args, CanonType);
1976
1977  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
1978  TemplateSpecializationTypeLoc TL
1979    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
1980  TL.setTemplateNameLoc(NameLoc);
1981  TL.setLAngleLoc(Args.getLAngleLoc());
1982  TL.setRAngleLoc(Args.getRAngleLoc());
1983  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
1984    TL.setArgLocInfo(i, Args[i].getLocInfo());
1985  return DI;
1986}
1987
1988QualType
1989ASTContext::getTemplateSpecializationType(TemplateName Template,
1990                                          const TemplateArgumentListInfo &Args,
1991                                          QualType Canon) {
1992  unsigned NumArgs = Args.size();
1993
1994  llvm::SmallVector<TemplateArgument, 4> ArgVec;
1995  ArgVec.reserve(NumArgs);
1996  for (unsigned i = 0; i != NumArgs; ++i)
1997    ArgVec.push_back(Args[i].getArgument());
1998
1999  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
2000                                       Canon);
2001}
2002
2003QualType
2004ASTContext::getTemplateSpecializationType(TemplateName Template,
2005                                          const TemplateArgument *Args,
2006                                          unsigned NumArgs,
2007                                          QualType Canon) {
2008  if (!Canon.isNull())
2009    Canon = getCanonicalType(Canon);
2010  else
2011    Canon = getCanonicalTemplateSpecializationType(Template, Args, NumArgs);
2012
2013  // Allocate the (non-canonical) template specialization type, but don't
2014  // try to unique it: these types typically have location information that
2015  // we don't unique and don't want to lose.
2016  void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2017                        sizeof(TemplateArgument) * NumArgs),
2018                       TypeAlignment);
2019  TemplateSpecializationType *Spec
2020    = new (Mem) TemplateSpecializationType(Template,
2021                                           Args, NumArgs,
2022                                           Canon);
2023
2024  Types.push_back(Spec);
2025  return QualType(Spec, 0);
2026}
2027
2028QualType
2029ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
2030                                                   const TemplateArgument *Args,
2031                                                   unsigned NumArgs) {
2032  // Build the canonical template specialization type.
2033  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
2034  llvm::SmallVector<TemplateArgument, 4> CanonArgs;
2035  CanonArgs.reserve(NumArgs);
2036  for (unsigned I = 0; I != NumArgs; ++I)
2037    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
2038
2039  // Determine whether this canonical template specialization type already
2040  // exists.
2041  llvm::FoldingSetNodeID ID;
2042  TemplateSpecializationType::Profile(ID, CanonTemplate,
2043                                      CanonArgs.data(), NumArgs, *this);
2044
2045  void *InsertPos = 0;
2046  TemplateSpecializationType *Spec
2047    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2048
2049  if (!Spec) {
2050    // Allocate a new canonical template specialization type.
2051    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2052                          sizeof(TemplateArgument) * NumArgs),
2053                         TypeAlignment);
2054    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
2055                                                CanonArgs.data(), NumArgs,
2056                                                QualType());
2057    Types.push_back(Spec);
2058    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
2059  }
2060
2061  assert(Spec->isDependentType() &&
2062         "Non-dependent template-id type must have a canonical type");
2063  return QualType(Spec, 0);
2064}
2065
2066QualType
2067ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
2068                              NestedNameSpecifier *NNS,
2069                              QualType NamedType) {
2070  llvm::FoldingSetNodeID ID;
2071  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2072
2073  void *InsertPos = 0;
2074  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2075  if (T)
2076    return QualType(T, 0);
2077
2078  QualType Canon = NamedType;
2079  if (!Canon.isCanonical()) {
2080    Canon = getCanonicalType(NamedType);
2081    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2082    assert(!CheckT && "Elaborated canonical type broken");
2083    (void)CheckT;
2084  }
2085
2086  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2087  Types.push_back(T);
2088  ElaboratedTypes.InsertNode(T, InsertPos);
2089  return QualType(T, 0);
2090}
2091
2092QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2093                                          NestedNameSpecifier *NNS,
2094                                          const IdentifierInfo *Name,
2095                                          QualType Canon) {
2096  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2097
2098  if (Canon.isNull()) {
2099    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2100    ElaboratedTypeKeyword CanonKeyword = Keyword;
2101    if (Keyword == ETK_None)
2102      CanonKeyword = ETK_Typename;
2103
2104    if (CanonNNS != NNS || CanonKeyword != Keyword)
2105      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2106  }
2107
2108  llvm::FoldingSetNodeID ID;
2109  DependentNameType::Profile(ID, Keyword, NNS, Name);
2110
2111  void *InsertPos = 0;
2112  DependentNameType *T
2113    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2114  if (T)
2115    return QualType(T, 0);
2116
2117  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2118  Types.push_back(T);
2119  DependentNameTypes.InsertNode(T, InsertPos);
2120  return QualType(T, 0);
2121}
2122
2123QualType
2124ASTContext::getDependentTemplateSpecializationType(
2125                                 ElaboratedTypeKeyword Keyword,
2126                                 NestedNameSpecifier *NNS,
2127                                 const IdentifierInfo *Name,
2128                                 const TemplateArgumentListInfo &Args) {
2129  // TODO: avoid this copy
2130  llvm::SmallVector<TemplateArgument, 16> ArgCopy;
2131  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2132    ArgCopy.push_back(Args[I].getArgument());
2133  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2134                                                ArgCopy.size(),
2135                                                ArgCopy.data());
2136}
2137
2138QualType
2139ASTContext::getDependentTemplateSpecializationType(
2140                                 ElaboratedTypeKeyword Keyword,
2141                                 NestedNameSpecifier *NNS,
2142                                 const IdentifierInfo *Name,
2143                                 unsigned NumArgs,
2144                                 const TemplateArgument *Args) {
2145  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2146
2147  llvm::FoldingSetNodeID ID;
2148  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2149                                               Name, NumArgs, Args);
2150
2151  void *InsertPos = 0;
2152  DependentTemplateSpecializationType *T
2153    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2154  if (T)
2155    return QualType(T, 0);
2156
2157  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2158
2159  ElaboratedTypeKeyword CanonKeyword = Keyword;
2160  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2161
2162  bool AnyNonCanonArgs = false;
2163  llvm::SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2164  for (unsigned I = 0; I != NumArgs; ++I) {
2165    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2166    if (!CanonArgs[I].structurallyEquals(Args[I]))
2167      AnyNonCanonArgs = true;
2168  }
2169
2170  QualType Canon;
2171  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2172    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2173                                                   Name, NumArgs,
2174                                                   CanonArgs.data());
2175
2176    // Find the insert position again.
2177    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2178  }
2179
2180  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2181                        sizeof(TemplateArgument) * NumArgs),
2182                       TypeAlignment);
2183  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2184                                                    Name, NumArgs, Args, Canon);
2185  Types.push_back(T);
2186  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2187  return QualType(T, 0);
2188}
2189
2190/// CmpProtocolNames - Comparison predicate for sorting protocols
2191/// alphabetically.
2192static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2193                            const ObjCProtocolDecl *RHS) {
2194  return LHS->getDeclName() < RHS->getDeclName();
2195}
2196
2197static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2198                                unsigned NumProtocols) {
2199  if (NumProtocols == 0) return true;
2200
2201  for (unsigned i = 1; i != NumProtocols; ++i)
2202    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]))
2203      return false;
2204  return true;
2205}
2206
2207static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2208                                   unsigned &NumProtocols) {
2209  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2210
2211  // Sort protocols, keyed by name.
2212  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2213
2214  // Remove duplicates.
2215  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2216  NumProtocols = ProtocolsEnd-Protocols;
2217}
2218
2219QualType ASTContext::getObjCObjectType(QualType BaseType,
2220                                       ObjCProtocolDecl * const *Protocols,
2221                                       unsigned NumProtocols) {
2222  // If the base type is an interface and there aren't any protocols
2223  // to add, then the interface type will do just fine.
2224  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2225    return BaseType;
2226
2227  // Look in the folding set for an existing type.
2228  llvm::FoldingSetNodeID ID;
2229  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2230  void *InsertPos = 0;
2231  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2232    return QualType(QT, 0);
2233
2234  // Build the canonical type, which has the canonical base type and
2235  // a sorted-and-uniqued list of protocols.
2236  QualType Canonical;
2237  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2238  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2239    if (!ProtocolsSorted) {
2240      llvm::SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2241                                                     Protocols + NumProtocols);
2242      unsigned UniqueCount = NumProtocols;
2243
2244      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2245      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2246                                    &Sorted[0], UniqueCount);
2247    } else {
2248      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2249                                    Protocols, NumProtocols);
2250    }
2251
2252    // Regenerate InsertPos.
2253    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2254  }
2255
2256  unsigned Size = sizeof(ObjCObjectTypeImpl);
2257  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2258  void *Mem = Allocate(Size, TypeAlignment);
2259  ObjCObjectTypeImpl *T =
2260    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2261
2262  Types.push_back(T);
2263  ObjCObjectTypes.InsertNode(T, InsertPos);
2264  return QualType(T, 0);
2265}
2266
2267/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2268/// the given object type.
2269QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) {
2270  llvm::FoldingSetNodeID ID;
2271  ObjCObjectPointerType::Profile(ID, ObjectT);
2272
2273  void *InsertPos = 0;
2274  if (ObjCObjectPointerType *QT =
2275              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2276    return QualType(QT, 0);
2277
2278  // Find the canonical object type.
2279  QualType Canonical;
2280  if (!ObjectT.isCanonical()) {
2281    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2282
2283    // Regenerate InsertPos.
2284    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2285  }
2286
2287  // No match.
2288  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2289  ObjCObjectPointerType *QType =
2290    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2291
2292  Types.push_back(QType);
2293  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2294  return QualType(QType, 0);
2295}
2296
2297/// getObjCInterfaceType - Return the unique reference to the type for the
2298/// specified ObjC interface decl. The list of protocols is optional.
2299QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl) {
2300  if (Decl->TypeForDecl)
2301    return QualType(Decl->TypeForDecl, 0);
2302
2303  // FIXME: redeclarations?
2304  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2305  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2306  Decl->TypeForDecl = T;
2307  Types.push_back(T);
2308  return QualType(T, 0);
2309}
2310
2311/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2312/// TypeOfExprType AST's (since expression's are never shared). For example,
2313/// multiple declarations that refer to "typeof(x)" all contain different
2314/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2315/// on canonical type's (which are always unique).
2316QualType ASTContext::getTypeOfExprType(Expr *tofExpr) {
2317  TypeOfExprType *toe;
2318  if (tofExpr->isTypeDependent()) {
2319    llvm::FoldingSetNodeID ID;
2320    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2321
2322    void *InsertPos = 0;
2323    DependentTypeOfExprType *Canon
2324      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2325    if (Canon) {
2326      // We already have a "canonical" version of an identical, dependent
2327      // typeof(expr) type. Use that as our canonical type.
2328      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2329                                          QualType((TypeOfExprType*)Canon, 0));
2330    }
2331    else {
2332      // Build a new, canonical typeof(expr) type.
2333      Canon
2334        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2335      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2336      toe = Canon;
2337    }
2338  } else {
2339    QualType Canonical = getCanonicalType(tofExpr->getType());
2340    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2341  }
2342  Types.push_back(toe);
2343  return QualType(toe, 0);
2344}
2345
2346/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2347/// TypeOfType AST's. The only motivation to unique these nodes would be
2348/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2349/// an issue. This doesn't effect the type checker, since it operates
2350/// on canonical type's (which are always unique).
2351QualType ASTContext::getTypeOfType(QualType tofType) {
2352  QualType Canonical = getCanonicalType(tofType);
2353  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2354  Types.push_back(tot);
2355  return QualType(tot, 0);
2356}
2357
2358/// getDecltypeForExpr - Given an expr, will return the decltype for that
2359/// expression, according to the rules in C++0x [dcl.type.simple]p4
2360static QualType getDecltypeForExpr(const Expr *e, ASTContext &Context) {
2361  if (e->isTypeDependent())
2362    return Context.DependentTy;
2363
2364  // If e is an id expression or a class member access, decltype(e) is defined
2365  // as the type of the entity named by e.
2366  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2367    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2368      return VD->getType();
2369  }
2370  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2371    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2372      return FD->getType();
2373  }
2374  // If e is a function call or an invocation of an overloaded operator,
2375  // (parentheses around e are ignored), decltype(e) is defined as the
2376  // return type of that function.
2377  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2378    return CE->getCallReturnType();
2379
2380  QualType T = e->getType();
2381
2382  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2383  // defined as T&, otherwise decltype(e) is defined as T.
2384  if (e->isLvalue(Context) == Expr::LV_Valid)
2385    T = Context.getLValueReferenceType(T);
2386
2387  return T;
2388}
2389
2390/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2391/// DecltypeType AST's. The only motivation to unique these nodes would be
2392/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2393/// an issue. This doesn't effect the type checker, since it operates
2394/// on canonical type's (which are always unique).
2395QualType ASTContext::getDecltypeType(Expr *e) {
2396  DecltypeType *dt;
2397  if (e->isTypeDependent()) {
2398    llvm::FoldingSetNodeID ID;
2399    DependentDecltypeType::Profile(ID, *this, e);
2400
2401    void *InsertPos = 0;
2402    DependentDecltypeType *Canon
2403      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2404    if (Canon) {
2405      // We already have a "canonical" version of an equivalent, dependent
2406      // decltype type. Use that as our canonical type.
2407      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2408                                       QualType((DecltypeType*)Canon, 0));
2409    }
2410    else {
2411      // Build a new, canonical typeof(expr) type.
2412      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2413      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2414      dt = Canon;
2415    }
2416  } else {
2417    QualType T = getDecltypeForExpr(e, *this);
2418    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2419  }
2420  Types.push_back(dt);
2421  return QualType(dt, 0);
2422}
2423
2424/// getTagDeclType - Return the unique reference to the type for the
2425/// specified TagDecl (struct/union/class/enum) decl.
2426QualType ASTContext::getTagDeclType(const TagDecl *Decl) {
2427  assert (Decl);
2428  // FIXME: What is the design on getTagDeclType when it requires casting
2429  // away const?  mutable?
2430  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2431}
2432
2433/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2434/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2435/// needs to agree with the definition in <stddef.h>.
2436CanQualType ASTContext::getSizeType() const {
2437  return getFromTargetType(Target.getSizeType());
2438}
2439
2440/// getSignedWCharType - Return the type of "signed wchar_t".
2441/// Used when in C++, as a GCC extension.
2442QualType ASTContext::getSignedWCharType() const {
2443  // FIXME: derive from "Target" ?
2444  return WCharTy;
2445}
2446
2447/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
2448/// Used when in C++, as a GCC extension.
2449QualType ASTContext::getUnsignedWCharType() const {
2450  // FIXME: derive from "Target" ?
2451  return UnsignedIntTy;
2452}
2453
2454/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
2455/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
2456QualType ASTContext::getPointerDiffType() const {
2457  return getFromTargetType(Target.getPtrDiffType(0));
2458}
2459
2460//===----------------------------------------------------------------------===//
2461//                              Type Operators
2462//===----------------------------------------------------------------------===//
2463
2464CanQualType ASTContext::getCanonicalParamType(QualType T) {
2465  // Push qualifiers into arrays, and then discard any remaining
2466  // qualifiers.
2467  T = getCanonicalType(T);
2468  T = getVariableArrayDecayedType(T);
2469  const Type *Ty = T.getTypePtr();
2470  QualType Result;
2471  if (isa<ArrayType>(Ty)) {
2472    Result = getArrayDecayedType(QualType(Ty,0));
2473  } else if (isa<FunctionType>(Ty)) {
2474    Result = getPointerType(QualType(Ty, 0));
2475  } else {
2476    Result = QualType(Ty, 0);
2477  }
2478
2479  return CanQualType::CreateUnsafe(Result);
2480}
2481
2482/// getCanonicalType - Return the canonical (structural) type corresponding to
2483/// the specified potentially non-canonical type.  The non-canonical version
2484/// of a type may have many "decorated" versions of types.  Decorators can
2485/// include typedefs, 'typeof' operators, etc. The returned type is guaranteed
2486/// to be free of any of these, allowing two canonical types to be compared
2487/// for exact equality with a simple pointer comparison.
2488CanQualType ASTContext::getCanonicalType(QualType T) {
2489  QualifierCollector Quals;
2490  const Type *Ptr = Quals.strip(T);
2491  QualType CanType = Ptr->getCanonicalTypeInternal();
2492
2493  // The canonical internal type will be the canonical type *except*
2494  // that we push type qualifiers down through array types.
2495
2496  // If there are no new qualifiers to push down, stop here.
2497  if (!Quals.hasQualifiers())
2498    return CanQualType::CreateUnsafe(CanType);
2499
2500  // If the type qualifiers are on an array type, get the canonical
2501  // type of the array with the qualifiers applied to the element
2502  // type.
2503  ArrayType *AT = dyn_cast<ArrayType>(CanType);
2504  if (!AT)
2505    return CanQualType::CreateUnsafe(getQualifiedType(CanType, Quals));
2506
2507  // Get the canonical version of the element with the extra qualifiers on it.
2508  // This can recursively sink qualifiers through multiple levels of arrays.
2509  QualType NewEltTy = getQualifiedType(AT->getElementType(), Quals);
2510  NewEltTy = getCanonicalType(NewEltTy);
2511
2512  if (ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
2513    return CanQualType::CreateUnsafe(
2514             getConstantArrayType(NewEltTy, CAT->getSize(),
2515                                  CAT->getSizeModifier(),
2516                                  CAT->getIndexTypeCVRQualifiers()));
2517  if (IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT))
2518    return CanQualType::CreateUnsafe(
2519             getIncompleteArrayType(NewEltTy, IAT->getSizeModifier(),
2520                                    IAT->getIndexTypeCVRQualifiers()));
2521
2522  if (DependentSizedArrayType *DSAT = dyn_cast<DependentSizedArrayType>(AT))
2523    return CanQualType::CreateUnsafe(
2524             getDependentSizedArrayType(NewEltTy,
2525                                        DSAT->getSizeExpr() ?
2526                                          DSAT->getSizeExpr()->Retain() : 0,
2527                                        DSAT->getSizeModifier(),
2528                                        DSAT->getIndexTypeCVRQualifiers(),
2529                        DSAT->getBracketsRange())->getCanonicalTypeInternal());
2530
2531  VariableArrayType *VAT = cast<VariableArrayType>(AT);
2532  return CanQualType::CreateUnsafe(getVariableArrayType(NewEltTy,
2533                                                        VAT->getSizeExpr() ?
2534                                              VAT->getSizeExpr()->Retain() : 0,
2535                                                        VAT->getSizeModifier(),
2536                                              VAT->getIndexTypeCVRQualifiers(),
2537                                                     VAT->getBracketsRange()));
2538}
2539
2540QualType ASTContext::getUnqualifiedArrayType(QualType T,
2541                                             Qualifiers &Quals) {
2542  Quals = T.getQualifiers();
2543  const ArrayType *AT = getAsArrayType(T);
2544  if (!AT) {
2545    return T.getUnqualifiedType();
2546  }
2547
2548  QualType Elt = AT->getElementType();
2549  QualType UnqualElt = getUnqualifiedArrayType(Elt, Quals);
2550  if (Elt == UnqualElt)
2551    return T;
2552
2553  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
2554    return getConstantArrayType(UnqualElt, CAT->getSize(),
2555                                CAT->getSizeModifier(), 0);
2556  }
2557
2558  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
2559    return getIncompleteArrayType(UnqualElt, IAT->getSizeModifier(), 0);
2560  }
2561
2562  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
2563    return getVariableArrayType(UnqualElt,
2564                                VAT->getSizeExpr() ?
2565                                VAT->getSizeExpr()->Retain() : 0,
2566                                VAT->getSizeModifier(),
2567                                VAT->getIndexTypeCVRQualifiers(),
2568                                VAT->getBracketsRange());
2569  }
2570
2571  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
2572  return getDependentSizedArrayType(UnqualElt, DSAT->getSizeExpr()->Retain(),
2573                                    DSAT->getSizeModifier(), 0,
2574                                    SourceRange());
2575}
2576
2577/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
2578/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
2579/// they point to and return true. If T1 and T2 aren't pointer types
2580/// or pointer-to-member types, or if they are not similar at this
2581/// level, returns false and leaves T1 and T2 unchanged. Top-level
2582/// qualifiers on T1 and T2 are ignored. This function will typically
2583/// be called in a loop that successively "unwraps" pointer and
2584/// pointer-to-member types to compare them at each level.
2585bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
2586  const PointerType *T1PtrType = T1->getAs<PointerType>(),
2587                    *T2PtrType = T2->getAs<PointerType>();
2588  if (T1PtrType && T2PtrType) {
2589    T1 = T1PtrType->getPointeeType();
2590    T2 = T2PtrType->getPointeeType();
2591    return true;
2592  }
2593
2594  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
2595                          *T2MPType = T2->getAs<MemberPointerType>();
2596  if (T1MPType && T2MPType &&
2597      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
2598                             QualType(T2MPType->getClass(), 0))) {
2599    T1 = T1MPType->getPointeeType();
2600    T2 = T2MPType->getPointeeType();
2601    return true;
2602  }
2603
2604  if (getLangOptions().ObjC1) {
2605    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
2606                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
2607    if (T1OPType && T2OPType) {
2608      T1 = T1OPType->getPointeeType();
2609      T2 = T2OPType->getPointeeType();
2610      return true;
2611    }
2612  }
2613
2614  // FIXME: Block pointers, too?
2615
2616  return false;
2617}
2618
2619DeclarationNameInfo ASTContext::getNameForTemplate(TemplateName Name,
2620                                                   SourceLocation NameLoc) {
2621  if (TemplateDecl *TD = Name.getAsTemplateDecl())
2622    // DNInfo work in progress: CHECKME: what about DNLoc?
2623    return DeclarationNameInfo(TD->getDeclName(), NameLoc);
2624
2625  if (DependentTemplateName *DTN = Name.getAsDependentTemplateName()) {
2626    DeclarationName DName;
2627    if (DTN->isIdentifier()) {
2628      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
2629      return DeclarationNameInfo(DName, NameLoc);
2630    } else {
2631      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
2632      // DNInfo work in progress: FIXME: source locations?
2633      DeclarationNameLoc DNLoc;
2634      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
2635      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
2636      return DeclarationNameInfo(DName, NameLoc, DNLoc);
2637    }
2638  }
2639
2640  OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
2641  assert(Storage);
2642  // DNInfo work in progress: CHECKME: what about DNLoc?
2643  return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
2644}
2645
2646TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) {
2647  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
2648    if (TemplateTemplateParmDecl *TTP
2649                              = dyn_cast<TemplateTemplateParmDecl>(Template))
2650      Template = getCanonicalTemplateTemplateParmDecl(TTP);
2651
2652    // The canonical template name is the canonical template declaration.
2653    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
2654  }
2655
2656  assert(!Name.getAsOverloadedTemplate());
2657
2658  DependentTemplateName *DTN = Name.getAsDependentTemplateName();
2659  assert(DTN && "Non-dependent template names must refer to template decls.");
2660  return DTN->CanonicalTemplateName;
2661}
2662
2663bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
2664  X = getCanonicalTemplateName(X);
2665  Y = getCanonicalTemplateName(Y);
2666  return X.getAsVoidPointer() == Y.getAsVoidPointer();
2667}
2668
2669TemplateArgument
2670ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) {
2671  switch (Arg.getKind()) {
2672    case TemplateArgument::Null:
2673      return Arg;
2674
2675    case TemplateArgument::Expression:
2676      return Arg;
2677
2678    case TemplateArgument::Declaration:
2679      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
2680
2681    case TemplateArgument::Template:
2682      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
2683
2684    case TemplateArgument::Integral:
2685      return TemplateArgument(*Arg.getAsIntegral(),
2686                              getCanonicalType(Arg.getIntegralType()));
2687
2688    case TemplateArgument::Type:
2689      return TemplateArgument(getCanonicalType(Arg.getAsType()));
2690
2691    case TemplateArgument::Pack: {
2692      // FIXME: Allocate in ASTContext
2693      TemplateArgument *CanonArgs = new TemplateArgument[Arg.pack_size()];
2694      unsigned Idx = 0;
2695      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
2696                                        AEnd = Arg.pack_end();
2697           A != AEnd; (void)++A, ++Idx)
2698        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
2699
2700      TemplateArgument Result;
2701      Result.setArgumentPack(CanonArgs, Arg.pack_size(), false);
2702      return Result;
2703    }
2704  }
2705
2706  // Silence GCC warning
2707  assert(false && "Unhandled template argument kind");
2708  return TemplateArgument();
2709}
2710
2711NestedNameSpecifier *
2712ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) {
2713  if (!NNS)
2714    return 0;
2715
2716  switch (NNS->getKind()) {
2717  case NestedNameSpecifier::Identifier:
2718    // Canonicalize the prefix but keep the identifier the same.
2719    return NestedNameSpecifier::Create(*this,
2720                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
2721                                       NNS->getAsIdentifier());
2722
2723  case NestedNameSpecifier::Namespace:
2724    // A namespace is canonical; build a nested-name-specifier with
2725    // this namespace and no prefix.
2726    return NestedNameSpecifier::Create(*this, 0, NNS->getAsNamespace());
2727
2728  case NestedNameSpecifier::TypeSpec:
2729  case NestedNameSpecifier::TypeSpecWithTemplate: {
2730    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
2731    return NestedNameSpecifier::Create(*this, 0,
2732                 NNS->getKind() == NestedNameSpecifier::TypeSpecWithTemplate,
2733                                       T.getTypePtr());
2734  }
2735
2736  case NestedNameSpecifier::Global:
2737    // The global specifier is canonical and unique.
2738    return NNS;
2739  }
2740
2741  // Required to silence a GCC warning
2742  return 0;
2743}
2744
2745
2746const ArrayType *ASTContext::getAsArrayType(QualType T) {
2747  // Handle the non-qualified case efficiently.
2748  if (!T.hasLocalQualifiers()) {
2749    // Handle the common positive case fast.
2750    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
2751      return AT;
2752  }
2753
2754  // Handle the common negative case fast.
2755  QualType CType = T->getCanonicalTypeInternal();
2756  if (!isa<ArrayType>(CType))
2757    return 0;
2758
2759  // Apply any qualifiers from the array type to the element type.  This
2760  // implements C99 6.7.3p8: "If the specification of an array type includes
2761  // any type qualifiers, the element type is so qualified, not the array type."
2762
2763  // If we get here, we either have type qualifiers on the type, or we have
2764  // sugar such as a typedef in the way.  If we have type qualifiers on the type
2765  // we must propagate them down into the element type.
2766
2767  QualifierCollector Qs;
2768  const Type *Ty = Qs.strip(T.getDesugaredType());
2769
2770  // If we have a simple case, just return now.
2771  const ArrayType *ATy = dyn_cast<ArrayType>(Ty);
2772  if (ATy == 0 || Qs.empty())
2773    return ATy;
2774
2775  // Otherwise, we have an array and we have qualifiers on it.  Push the
2776  // qualifiers into the array element type and return a new array type.
2777  // Get the canonical version of the element with the extra qualifiers on it.
2778  // This can recursively sink qualifiers through multiple levels of arrays.
2779  QualType NewEltTy = getQualifiedType(ATy->getElementType(), Qs);
2780
2781  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
2782    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
2783                                                CAT->getSizeModifier(),
2784                                           CAT->getIndexTypeCVRQualifiers()));
2785  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
2786    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
2787                                                  IAT->getSizeModifier(),
2788                                           IAT->getIndexTypeCVRQualifiers()));
2789
2790  if (const DependentSizedArrayType *DSAT
2791        = dyn_cast<DependentSizedArrayType>(ATy))
2792    return cast<ArrayType>(
2793                     getDependentSizedArrayType(NewEltTy,
2794                                                DSAT->getSizeExpr() ?
2795                                              DSAT->getSizeExpr()->Retain() : 0,
2796                                                DSAT->getSizeModifier(),
2797                                              DSAT->getIndexTypeCVRQualifiers(),
2798                                                DSAT->getBracketsRange()));
2799
2800  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
2801  return cast<ArrayType>(getVariableArrayType(NewEltTy,
2802                                              VAT->getSizeExpr() ?
2803                                              VAT->getSizeExpr()->Retain() : 0,
2804                                              VAT->getSizeModifier(),
2805                                              VAT->getIndexTypeCVRQualifiers(),
2806                                              VAT->getBracketsRange()));
2807}
2808
2809/// getArrayDecayedType - Return the properly qualified result of decaying the
2810/// specified array type to a pointer.  This operation is non-trivial when
2811/// handling typedefs etc.  The canonical type of "T" must be an array type,
2812/// this returns a pointer to a properly qualified element of the array.
2813///
2814/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
2815QualType ASTContext::getArrayDecayedType(QualType Ty) {
2816  // Get the element type with 'getAsArrayType' so that we don't lose any
2817  // typedefs in the element type of the array.  This also handles propagation
2818  // of type qualifiers from the array type into the element type if present
2819  // (C99 6.7.3p8).
2820  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
2821  assert(PrettyArrayType && "Not an array type!");
2822
2823  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
2824
2825  // int x[restrict 4] ->  int *restrict
2826  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
2827}
2828
2829QualType ASTContext::getBaseElementType(QualType QT) {
2830  QualifierCollector Qs;
2831  while (const ArrayType *AT = getAsArrayType(QualType(Qs.strip(QT), 0)))
2832    QT = AT->getElementType();
2833  return Qs.apply(QT);
2834}
2835
2836QualType ASTContext::getBaseElementType(const ArrayType *AT) {
2837  QualType ElemTy = AT->getElementType();
2838
2839  if (const ArrayType *AT = getAsArrayType(ElemTy))
2840    return getBaseElementType(AT);
2841
2842  return ElemTy;
2843}
2844
2845/// getConstantArrayElementCount - Returns number of constant array elements.
2846uint64_t
2847ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
2848  uint64_t ElementCount = 1;
2849  do {
2850    ElementCount *= CA->getSize().getZExtValue();
2851    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
2852  } while (CA);
2853  return ElementCount;
2854}
2855
2856/// getFloatingRank - Return a relative rank for floating point types.
2857/// This routine will assert if passed a built-in type that isn't a float.
2858static FloatingRank getFloatingRank(QualType T) {
2859  if (const ComplexType *CT = T->getAs<ComplexType>())
2860    return getFloatingRank(CT->getElementType());
2861
2862  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
2863  switch (T->getAs<BuiltinType>()->getKind()) {
2864  default: assert(0 && "getFloatingRank(): not a floating type");
2865  case BuiltinType::Float:      return FloatRank;
2866  case BuiltinType::Double:     return DoubleRank;
2867  case BuiltinType::LongDouble: return LongDoubleRank;
2868  }
2869}
2870
2871/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
2872/// point or a complex type (based on typeDomain/typeSize).
2873/// 'typeDomain' is a real floating point or complex type.
2874/// 'typeSize' is a real floating point or complex type.
2875QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
2876                                                       QualType Domain) const {
2877  FloatingRank EltRank = getFloatingRank(Size);
2878  if (Domain->isComplexType()) {
2879    switch (EltRank) {
2880    default: assert(0 && "getFloatingRank(): illegal value for rank");
2881    case FloatRank:      return FloatComplexTy;
2882    case DoubleRank:     return DoubleComplexTy;
2883    case LongDoubleRank: return LongDoubleComplexTy;
2884    }
2885  }
2886
2887  assert(Domain->isRealFloatingType() && "Unknown domain!");
2888  switch (EltRank) {
2889  default: assert(0 && "getFloatingRank(): illegal value for rank");
2890  case FloatRank:      return FloatTy;
2891  case DoubleRank:     return DoubleTy;
2892  case LongDoubleRank: return LongDoubleTy;
2893  }
2894}
2895
2896/// getFloatingTypeOrder - Compare the rank of the two specified floating
2897/// point types, ignoring the domain of the type (i.e. 'double' ==
2898/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2899/// LHS < RHS, return -1.
2900int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) {
2901  FloatingRank LHSR = getFloatingRank(LHS);
2902  FloatingRank RHSR = getFloatingRank(RHS);
2903
2904  if (LHSR == RHSR)
2905    return 0;
2906  if (LHSR > RHSR)
2907    return 1;
2908  return -1;
2909}
2910
2911/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
2912/// routine will assert if passed a built-in type that isn't an integer or enum,
2913/// or if it is not canonicalized.
2914unsigned ASTContext::getIntegerRank(Type *T) {
2915  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
2916  if (EnumType* ET = dyn_cast<EnumType>(T))
2917    T = ET->getDecl()->getPromotionType().getTypePtr();
2918
2919  if (T->isSpecificBuiltinType(BuiltinType::WChar))
2920    T = getFromTargetType(Target.getWCharType()).getTypePtr();
2921
2922  if (T->isSpecificBuiltinType(BuiltinType::Char16))
2923    T = getFromTargetType(Target.getChar16Type()).getTypePtr();
2924
2925  if (T->isSpecificBuiltinType(BuiltinType::Char32))
2926    T = getFromTargetType(Target.getChar32Type()).getTypePtr();
2927
2928  switch (cast<BuiltinType>(T)->getKind()) {
2929  default: assert(0 && "getIntegerRank(): not a built-in integer");
2930  case BuiltinType::Bool:
2931    return 1 + (getIntWidth(BoolTy) << 3);
2932  case BuiltinType::Char_S:
2933  case BuiltinType::Char_U:
2934  case BuiltinType::SChar:
2935  case BuiltinType::UChar:
2936    return 2 + (getIntWidth(CharTy) << 3);
2937  case BuiltinType::Short:
2938  case BuiltinType::UShort:
2939    return 3 + (getIntWidth(ShortTy) << 3);
2940  case BuiltinType::Int:
2941  case BuiltinType::UInt:
2942    return 4 + (getIntWidth(IntTy) << 3);
2943  case BuiltinType::Long:
2944  case BuiltinType::ULong:
2945    return 5 + (getIntWidth(LongTy) << 3);
2946  case BuiltinType::LongLong:
2947  case BuiltinType::ULongLong:
2948    return 6 + (getIntWidth(LongLongTy) << 3);
2949  case BuiltinType::Int128:
2950  case BuiltinType::UInt128:
2951    return 7 + (getIntWidth(Int128Ty) << 3);
2952  }
2953}
2954
2955/// \brief Whether this is a promotable bitfield reference according
2956/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
2957///
2958/// \returns the type this bit-field will promote to, or NULL if no
2959/// promotion occurs.
2960QualType ASTContext::isPromotableBitField(Expr *E) {
2961  if (E->isTypeDependent() || E->isValueDependent())
2962    return QualType();
2963
2964  FieldDecl *Field = E->getBitField();
2965  if (!Field)
2966    return QualType();
2967
2968  QualType FT = Field->getType();
2969
2970  llvm::APSInt BitWidthAP = Field->getBitWidth()->EvaluateAsInt(*this);
2971  uint64_t BitWidth = BitWidthAP.getZExtValue();
2972  uint64_t IntSize = getTypeSize(IntTy);
2973  // GCC extension compatibility: if the bit-field size is less than or equal
2974  // to the size of int, it gets promoted no matter what its type is.
2975  // For instance, unsigned long bf : 4 gets promoted to signed int.
2976  if (BitWidth < IntSize)
2977    return IntTy;
2978
2979  if (BitWidth == IntSize)
2980    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
2981
2982  // Types bigger than int are not subject to promotions, and therefore act
2983  // like the base type.
2984  // FIXME: This doesn't quite match what gcc does, but what gcc does here
2985  // is ridiculous.
2986  return QualType();
2987}
2988
2989/// getPromotedIntegerType - Returns the type that Promotable will
2990/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
2991/// integer type.
2992QualType ASTContext::getPromotedIntegerType(QualType Promotable) {
2993  assert(!Promotable.isNull());
2994  assert(Promotable->isPromotableIntegerType());
2995  if (const EnumType *ET = Promotable->getAs<EnumType>())
2996    return ET->getDecl()->getPromotionType();
2997  if (Promotable->isSignedIntegerType())
2998    return IntTy;
2999  uint64_t PromotableSize = getTypeSize(Promotable);
3000  uint64_t IntSize = getTypeSize(IntTy);
3001  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3002  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3003}
3004
3005/// getIntegerTypeOrder - Returns the highest ranked integer type:
3006/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3007/// LHS < RHS, return -1.
3008int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) {
3009  Type *LHSC = getCanonicalType(LHS).getTypePtr();
3010  Type *RHSC = getCanonicalType(RHS).getTypePtr();
3011  if (LHSC == RHSC) return 0;
3012
3013  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3014  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3015
3016  unsigned LHSRank = getIntegerRank(LHSC);
3017  unsigned RHSRank = getIntegerRank(RHSC);
3018
3019  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3020    if (LHSRank == RHSRank) return 0;
3021    return LHSRank > RHSRank ? 1 : -1;
3022  }
3023
3024  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3025  if (LHSUnsigned) {
3026    // If the unsigned [LHS] type is larger, return it.
3027    if (LHSRank >= RHSRank)
3028      return 1;
3029
3030    // If the signed type can represent all values of the unsigned type, it
3031    // wins.  Because we are dealing with 2's complement and types that are
3032    // powers of two larger than each other, this is always safe.
3033    return -1;
3034  }
3035
3036  // If the unsigned [RHS] type is larger, return it.
3037  if (RHSRank >= LHSRank)
3038    return -1;
3039
3040  // If the signed type can represent all values of the unsigned type, it
3041  // wins.  Because we are dealing with 2's complement and types that are
3042  // powers of two larger than each other, this is always safe.
3043  return 1;
3044}
3045
3046static RecordDecl *
3047CreateRecordDecl(ASTContext &Ctx, RecordDecl::TagKind TK, DeclContext *DC,
3048                 SourceLocation L, IdentifierInfo *Id) {
3049  if (Ctx.getLangOptions().CPlusPlus)
3050    return CXXRecordDecl::Create(Ctx, TK, DC, L, Id);
3051  else
3052    return RecordDecl::Create(Ctx, TK, DC, L, Id);
3053}
3054
3055// getCFConstantStringType - Return the type used for constant CFStrings.
3056QualType ASTContext::getCFConstantStringType() {
3057  if (!CFConstantStringTypeDecl) {
3058    CFConstantStringTypeDecl =
3059      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3060                       &Idents.get("NSConstantString"));
3061    CFConstantStringTypeDecl->startDefinition();
3062
3063    QualType FieldTypes[4];
3064
3065    // const int *isa;
3066    FieldTypes[0] = getPointerType(IntTy.withConst());
3067    // int flags;
3068    FieldTypes[1] = IntTy;
3069    // const char *str;
3070    FieldTypes[2] = getPointerType(CharTy.withConst());
3071    // long length;
3072    FieldTypes[3] = LongTy;
3073
3074    // Create fields
3075    for (unsigned i = 0; i < 4; ++i) {
3076      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3077                                           SourceLocation(), 0,
3078                                           FieldTypes[i], /*TInfo=*/0,
3079                                           /*BitWidth=*/0,
3080                                           /*Mutable=*/false);
3081      Field->setAccess(AS_public);
3082      CFConstantStringTypeDecl->addDecl(Field);
3083    }
3084
3085    CFConstantStringTypeDecl->completeDefinition();
3086  }
3087
3088  return getTagDeclType(CFConstantStringTypeDecl);
3089}
3090
3091void ASTContext::setCFConstantStringType(QualType T) {
3092  const RecordType *Rec = T->getAs<RecordType>();
3093  assert(Rec && "Invalid CFConstantStringType");
3094  CFConstantStringTypeDecl = Rec->getDecl();
3095}
3096
3097// getNSConstantStringType - Return the type used for constant NSStrings.
3098QualType ASTContext::getNSConstantStringType() {
3099  if (!NSConstantStringTypeDecl) {
3100    NSConstantStringTypeDecl =
3101    CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3102                     &Idents.get("__builtin_NSString"));
3103    NSConstantStringTypeDecl->startDefinition();
3104
3105    QualType FieldTypes[3];
3106
3107    // const int *isa;
3108    FieldTypes[0] = getPointerType(IntTy.withConst());
3109    // const char *str;
3110    FieldTypes[1] = getPointerType(CharTy.withConst());
3111    // unsigned int length;
3112    FieldTypes[2] = UnsignedIntTy;
3113
3114    // Create fields
3115    for (unsigned i = 0; i < 3; ++i) {
3116      FieldDecl *Field = FieldDecl::Create(*this, NSConstantStringTypeDecl,
3117                                           SourceLocation(), 0,
3118                                           FieldTypes[i], /*TInfo=*/0,
3119                                           /*BitWidth=*/0,
3120                                           /*Mutable=*/false);
3121      Field->setAccess(AS_public);
3122      NSConstantStringTypeDecl->addDecl(Field);
3123    }
3124
3125    NSConstantStringTypeDecl->completeDefinition();
3126  }
3127
3128  return getTagDeclType(NSConstantStringTypeDecl);
3129}
3130
3131void ASTContext::setNSConstantStringType(QualType T) {
3132  const RecordType *Rec = T->getAs<RecordType>();
3133  assert(Rec && "Invalid NSConstantStringType");
3134  NSConstantStringTypeDecl = Rec->getDecl();
3135}
3136
3137QualType ASTContext::getObjCFastEnumerationStateType() {
3138  if (!ObjCFastEnumerationStateTypeDecl) {
3139    ObjCFastEnumerationStateTypeDecl =
3140      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3141                       &Idents.get("__objcFastEnumerationState"));
3142    ObjCFastEnumerationStateTypeDecl->startDefinition();
3143
3144    QualType FieldTypes[] = {
3145      UnsignedLongTy,
3146      getPointerType(ObjCIdTypedefType),
3147      getPointerType(UnsignedLongTy),
3148      getConstantArrayType(UnsignedLongTy,
3149                           llvm::APInt(32, 5), ArrayType::Normal, 0)
3150    };
3151
3152    for (size_t i = 0; i < 4; ++i) {
3153      FieldDecl *Field = FieldDecl::Create(*this,
3154                                           ObjCFastEnumerationStateTypeDecl,
3155                                           SourceLocation(), 0,
3156                                           FieldTypes[i], /*TInfo=*/0,
3157                                           /*BitWidth=*/0,
3158                                           /*Mutable=*/false);
3159      Field->setAccess(AS_public);
3160      ObjCFastEnumerationStateTypeDecl->addDecl(Field);
3161    }
3162
3163    ObjCFastEnumerationStateTypeDecl->completeDefinition();
3164  }
3165
3166  return getTagDeclType(ObjCFastEnumerationStateTypeDecl);
3167}
3168
3169QualType ASTContext::getBlockDescriptorType() {
3170  if (BlockDescriptorType)
3171    return getTagDeclType(BlockDescriptorType);
3172
3173  RecordDecl *T;
3174  // FIXME: Needs the FlagAppleBlock bit.
3175  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3176                       &Idents.get("__block_descriptor"));
3177  T->startDefinition();
3178
3179  QualType FieldTypes[] = {
3180    UnsignedLongTy,
3181    UnsignedLongTy,
3182  };
3183
3184  const char *FieldNames[] = {
3185    "reserved",
3186    "Size"
3187  };
3188
3189  for (size_t i = 0; i < 2; ++i) {
3190    FieldDecl *Field = FieldDecl::Create(*this,
3191                                         T,
3192                                         SourceLocation(),
3193                                         &Idents.get(FieldNames[i]),
3194                                         FieldTypes[i], /*TInfo=*/0,
3195                                         /*BitWidth=*/0,
3196                                         /*Mutable=*/false);
3197    Field->setAccess(AS_public);
3198    T->addDecl(Field);
3199  }
3200
3201  T->completeDefinition();
3202
3203  BlockDescriptorType = T;
3204
3205  return getTagDeclType(BlockDescriptorType);
3206}
3207
3208void ASTContext::setBlockDescriptorType(QualType T) {
3209  const RecordType *Rec = T->getAs<RecordType>();
3210  assert(Rec && "Invalid BlockDescriptorType");
3211  BlockDescriptorType = Rec->getDecl();
3212}
3213
3214QualType ASTContext::getBlockDescriptorExtendedType() {
3215  if (BlockDescriptorExtendedType)
3216    return getTagDeclType(BlockDescriptorExtendedType);
3217
3218  RecordDecl *T;
3219  // FIXME: Needs the FlagAppleBlock bit.
3220  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3221                       &Idents.get("__block_descriptor_withcopydispose"));
3222  T->startDefinition();
3223
3224  QualType FieldTypes[] = {
3225    UnsignedLongTy,
3226    UnsignedLongTy,
3227    getPointerType(VoidPtrTy),
3228    getPointerType(VoidPtrTy)
3229  };
3230
3231  const char *FieldNames[] = {
3232    "reserved",
3233    "Size",
3234    "CopyFuncPtr",
3235    "DestroyFuncPtr"
3236  };
3237
3238  for (size_t i = 0; i < 4; ++i) {
3239    FieldDecl *Field = FieldDecl::Create(*this,
3240                                         T,
3241                                         SourceLocation(),
3242                                         &Idents.get(FieldNames[i]),
3243                                         FieldTypes[i], /*TInfo=*/0,
3244                                         /*BitWidth=*/0,
3245                                         /*Mutable=*/false);
3246    Field->setAccess(AS_public);
3247    T->addDecl(Field);
3248  }
3249
3250  T->completeDefinition();
3251
3252  BlockDescriptorExtendedType = T;
3253
3254  return getTagDeclType(BlockDescriptorExtendedType);
3255}
3256
3257void ASTContext::setBlockDescriptorExtendedType(QualType T) {
3258  const RecordType *Rec = T->getAs<RecordType>();
3259  assert(Rec && "Invalid BlockDescriptorType");
3260  BlockDescriptorExtendedType = Rec->getDecl();
3261}
3262
3263bool ASTContext::BlockRequiresCopying(QualType Ty) {
3264  if (Ty->isBlockPointerType())
3265    return true;
3266  if (isObjCNSObjectType(Ty))
3267    return true;
3268  if (Ty->isObjCObjectPointerType())
3269    return true;
3270  return false;
3271}
3272
3273QualType ASTContext::BuildByRefType(llvm::StringRef DeclName, QualType Ty) {
3274  //  type = struct __Block_byref_1_X {
3275  //    void *__isa;
3276  //    struct __Block_byref_1_X *__forwarding;
3277  //    unsigned int __flags;
3278  //    unsigned int __size;
3279  //    void *__copy_helper;            // as needed
3280  //    void *__destroy_help            // as needed
3281  //    int X;
3282  //  } *
3283
3284  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3285
3286  // FIXME: Move up
3287  llvm::SmallString<36> Name;
3288  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3289                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3290  RecordDecl *T;
3291  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3292                       &Idents.get(Name.str()));
3293  T->startDefinition();
3294  QualType Int32Ty = IntTy;
3295  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3296  QualType FieldTypes[] = {
3297    getPointerType(VoidPtrTy),
3298    getPointerType(getTagDeclType(T)),
3299    Int32Ty,
3300    Int32Ty,
3301    getPointerType(VoidPtrTy),
3302    getPointerType(VoidPtrTy),
3303    Ty
3304  };
3305
3306  llvm::StringRef FieldNames[] = {
3307    "__isa",
3308    "__forwarding",
3309    "__flags",
3310    "__size",
3311    "__copy_helper",
3312    "__destroy_helper",
3313    DeclName,
3314  };
3315
3316  for (size_t i = 0; i < 7; ++i) {
3317    if (!HasCopyAndDispose && i >=4 && i <= 5)
3318      continue;
3319    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3320                                         &Idents.get(FieldNames[i]),
3321                                         FieldTypes[i], /*TInfo=*/0,
3322                                         /*BitWidth=*/0, /*Mutable=*/false);
3323    Field->setAccess(AS_public);
3324    T->addDecl(Field);
3325  }
3326
3327  T->completeDefinition();
3328
3329  return getPointerType(getTagDeclType(T));
3330}
3331
3332
3333QualType ASTContext::getBlockParmType(
3334  bool BlockHasCopyDispose,
3335  llvm::SmallVectorImpl<const Expr *> &Layout) {
3336
3337  // FIXME: Move up
3338  llvm::SmallString<36> Name;
3339  llvm::raw_svector_ostream(Name) << "__block_literal_"
3340                                  << ++UniqueBlockParmTypeID;
3341  RecordDecl *T;
3342  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3343                       &Idents.get(Name.str()));
3344  T->startDefinition();
3345  QualType FieldTypes[] = {
3346    getPointerType(VoidPtrTy),
3347    IntTy,
3348    IntTy,
3349    getPointerType(VoidPtrTy),
3350    (BlockHasCopyDispose ?
3351     getPointerType(getBlockDescriptorExtendedType()) :
3352     getPointerType(getBlockDescriptorType()))
3353  };
3354
3355  const char *FieldNames[] = {
3356    "__isa",
3357    "__flags",
3358    "__reserved",
3359    "__FuncPtr",
3360    "__descriptor"
3361  };
3362
3363  for (size_t i = 0; i < 5; ++i) {
3364    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3365                                         &Idents.get(FieldNames[i]),
3366                                         FieldTypes[i], /*TInfo=*/0,
3367                                         /*BitWidth=*/0, /*Mutable=*/false);
3368    Field->setAccess(AS_public);
3369    T->addDecl(Field);
3370  }
3371
3372  for (unsigned i = 0; i < Layout.size(); ++i) {
3373    const Expr *E = Layout[i];
3374
3375    QualType FieldType = E->getType();
3376    IdentifierInfo *FieldName = 0;
3377    if (isa<CXXThisExpr>(E)) {
3378      FieldName = &Idents.get("this");
3379    } else if (const BlockDeclRefExpr *BDRE = dyn_cast<BlockDeclRefExpr>(E)) {
3380      const ValueDecl *D = BDRE->getDecl();
3381      FieldName = D->getIdentifier();
3382      if (BDRE->isByRef())
3383        FieldType = BuildByRefType(D->getName(), FieldType);
3384    } else {
3385      // Padding.
3386      assert(isa<ConstantArrayType>(FieldType) &&
3387             isa<DeclRefExpr>(E) &&
3388             !cast<DeclRefExpr>(E)->getDecl()->getDeclName() &&
3389             "doesn't match characteristics of padding decl");
3390    }
3391
3392    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3393                                         FieldName, FieldType, /*TInfo=*/0,
3394                                         /*BitWidth=*/0, /*Mutable=*/false);
3395    Field->setAccess(AS_public);
3396    T->addDecl(Field);
3397  }
3398
3399  T->completeDefinition();
3400
3401  return getPointerType(getTagDeclType(T));
3402}
3403
3404void ASTContext::setObjCFastEnumerationStateType(QualType T) {
3405  const RecordType *Rec = T->getAs<RecordType>();
3406  assert(Rec && "Invalid ObjCFAstEnumerationStateType");
3407  ObjCFastEnumerationStateTypeDecl = Rec->getDecl();
3408}
3409
3410// This returns true if a type has been typedefed to BOOL:
3411// typedef <type> BOOL;
3412static bool isTypeTypedefedAsBOOL(QualType T) {
3413  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3414    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3415      return II->isStr("BOOL");
3416
3417  return false;
3418}
3419
3420/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3421/// purpose.
3422CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) {
3423  CharUnits sz = getTypeSizeInChars(type);
3424
3425  // Make all integer and enum types at least as large as an int
3426  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3427    sz = std::max(sz, getTypeSizeInChars(IntTy));
3428  // Treat arrays as pointers, since that's how they're passed in.
3429  else if (type->isArrayType())
3430    sz = getTypeSizeInChars(VoidPtrTy);
3431  return sz;
3432}
3433
3434static inline
3435std::string charUnitsToString(const CharUnits &CU) {
3436  return llvm::itostr(CU.getQuantity());
3437}
3438
3439/// getObjCEncodingForBlockDecl - Return the encoded type for this block
3440/// declaration.
3441void ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr,
3442                                             std::string& S) {
3443  const BlockDecl *Decl = Expr->getBlockDecl();
3444  QualType BlockTy =
3445      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3446  // Encode result type.
3447  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3448  // Compute size of all parameters.
3449  // Start with computing size of a pointer in number of bytes.
3450  // FIXME: There might(should) be a better way of doing this computation!
3451  SourceLocation Loc;
3452  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3453  CharUnits ParmOffset = PtrSize;
3454  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3455       E = Decl->param_end(); PI != E; ++PI) {
3456    QualType PType = (*PI)->getType();
3457    CharUnits sz = getObjCEncodingTypeSize(PType);
3458    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3459    ParmOffset += sz;
3460  }
3461  // Size of the argument frame
3462  S += charUnitsToString(ParmOffset);
3463  // Block pointer and offset.
3464  S += "@?0";
3465  ParmOffset = PtrSize;
3466
3467  // Argument types.
3468  ParmOffset = PtrSize;
3469  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3470       Decl->param_end(); PI != E; ++PI) {
3471    ParmVarDecl *PVDecl = *PI;
3472    QualType PType = PVDecl->getOriginalType();
3473    if (const ArrayType *AT =
3474          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3475      // Use array's original type only if it has known number of
3476      // elements.
3477      if (!isa<ConstantArrayType>(AT))
3478        PType = PVDecl->getType();
3479    } else if (PType->isFunctionType())
3480      PType = PVDecl->getType();
3481    getObjCEncodingForType(PType, S);
3482    S += charUnitsToString(ParmOffset);
3483    ParmOffset += getObjCEncodingTypeSize(PType);
3484  }
3485}
3486
3487/// getObjCEncodingForMethodDecl - Return the encoded type for this method
3488/// declaration.
3489void ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
3490                                              std::string& S) {
3491  // FIXME: This is not very efficient.
3492  // Encode type qualifer, 'in', 'inout', etc. for the return type.
3493  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
3494  // Encode result type.
3495  getObjCEncodingForType(Decl->getResultType(), S);
3496  // Compute size of all parameters.
3497  // Start with computing size of a pointer in number of bytes.
3498  // FIXME: There might(should) be a better way of doing this computation!
3499  SourceLocation Loc;
3500  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3501  // The first two arguments (self and _cmd) are pointers; account for
3502  // their size.
3503  CharUnits ParmOffset = 2 * PtrSize;
3504  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3505       E = Decl->sel_param_end(); PI != E; ++PI) {
3506    QualType PType = (*PI)->getType();
3507    CharUnits sz = getObjCEncodingTypeSize(PType);
3508    assert (sz.isPositive() &&
3509        "getObjCEncodingForMethodDecl - Incomplete param type");
3510    ParmOffset += sz;
3511  }
3512  S += charUnitsToString(ParmOffset);
3513  S += "@0:";
3514  S += charUnitsToString(PtrSize);
3515
3516  // Argument types.
3517  ParmOffset = 2 * PtrSize;
3518  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3519       E = Decl->sel_param_end(); PI != E; ++PI) {
3520    ParmVarDecl *PVDecl = *PI;
3521    QualType PType = PVDecl->getOriginalType();
3522    if (const ArrayType *AT =
3523          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3524      // Use array's original type only if it has known number of
3525      // elements.
3526      if (!isa<ConstantArrayType>(AT))
3527        PType = PVDecl->getType();
3528    } else if (PType->isFunctionType())
3529      PType = PVDecl->getType();
3530    // Process argument qualifiers for user supplied arguments; such as,
3531    // 'in', 'inout', etc.
3532    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
3533    getObjCEncodingForType(PType, S);
3534    S += charUnitsToString(ParmOffset);
3535    ParmOffset += getObjCEncodingTypeSize(PType);
3536  }
3537}
3538
3539/// getObjCEncodingForPropertyDecl - Return the encoded type for this
3540/// property declaration. If non-NULL, Container must be either an
3541/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
3542/// NULL when getting encodings for protocol properties.
3543/// Property attributes are stored as a comma-delimited C string. The simple
3544/// attributes readonly and bycopy are encoded as single characters. The
3545/// parametrized attributes, getter=name, setter=name, and ivar=name, are
3546/// encoded as single characters, followed by an identifier. Property types
3547/// are also encoded as a parametrized attribute. The characters used to encode
3548/// these attributes are defined by the following enumeration:
3549/// @code
3550/// enum PropertyAttributes {
3551/// kPropertyReadOnly = 'R',   // property is read-only.
3552/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
3553/// kPropertyByref = '&',  // property is a reference to the value last assigned
3554/// kPropertyDynamic = 'D',    // property is dynamic
3555/// kPropertyGetter = 'G',     // followed by getter selector name
3556/// kPropertySetter = 'S',     // followed by setter selector name
3557/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
3558/// kPropertyType = 't'              // followed by old-style type encoding.
3559/// kPropertyWeak = 'W'              // 'weak' property
3560/// kPropertyStrong = 'P'            // property GC'able
3561/// kPropertyNonAtomic = 'N'         // property non-atomic
3562/// };
3563/// @endcode
3564void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
3565                                                const Decl *Container,
3566                                                std::string& S) {
3567  // Collect information from the property implementation decl(s).
3568  bool Dynamic = false;
3569  ObjCPropertyImplDecl *SynthesizePID = 0;
3570
3571  // FIXME: Duplicated code due to poor abstraction.
3572  if (Container) {
3573    if (const ObjCCategoryImplDecl *CID =
3574        dyn_cast<ObjCCategoryImplDecl>(Container)) {
3575      for (ObjCCategoryImplDecl::propimpl_iterator
3576             i = CID->propimpl_begin(), e = CID->propimpl_end();
3577           i != e; ++i) {
3578        ObjCPropertyImplDecl *PID = *i;
3579        if (PID->getPropertyDecl() == PD) {
3580          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3581            Dynamic = true;
3582          } else {
3583            SynthesizePID = PID;
3584          }
3585        }
3586      }
3587    } else {
3588      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
3589      for (ObjCCategoryImplDecl::propimpl_iterator
3590             i = OID->propimpl_begin(), e = OID->propimpl_end();
3591           i != e; ++i) {
3592        ObjCPropertyImplDecl *PID = *i;
3593        if (PID->getPropertyDecl() == PD) {
3594          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3595            Dynamic = true;
3596          } else {
3597            SynthesizePID = PID;
3598          }
3599        }
3600      }
3601    }
3602  }
3603
3604  // FIXME: This is not very efficient.
3605  S = "T";
3606
3607  // Encode result type.
3608  // GCC has some special rules regarding encoding of properties which
3609  // closely resembles encoding of ivars.
3610  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
3611                             true /* outermost type */,
3612                             true /* encoding for property */);
3613
3614  if (PD->isReadOnly()) {
3615    S += ",R";
3616  } else {
3617    switch (PD->getSetterKind()) {
3618    case ObjCPropertyDecl::Assign: break;
3619    case ObjCPropertyDecl::Copy:   S += ",C"; break;
3620    case ObjCPropertyDecl::Retain: S += ",&"; break;
3621    }
3622  }
3623
3624  // It really isn't clear at all what this means, since properties
3625  // are "dynamic by default".
3626  if (Dynamic)
3627    S += ",D";
3628
3629  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
3630    S += ",N";
3631
3632  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
3633    S += ",G";
3634    S += PD->getGetterName().getAsString();
3635  }
3636
3637  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
3638    S += ",S";
3639    S += PD->getSetterName().getAsString();
3640  }
3641
3642  if (SynthesizePID) {
3643    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
3644    S += ",V";
3645    S += OID->getNameAsString();
3646  }
3647
3648  // FIXME: OBJCGC: weak & strong
3649}
3650
3651/// getLegacyIntegralTypeEncoding -
3652/// Another legacy compatibility encoding: 32-bit longs are encoded as
3653/// 'l' or 'L' , but not always.  For typedefs, we need to use
3654/// 'i' or 'I' instead if encoding a struct field, or a pointer!
3655///
3656void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
3657  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
3658    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
3659      if (BT->getKind() == BuiltinType::ULong &&
3660          ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3661        PointeeTy = UnsignedIntTy;
3662      else
3663        if (BT->getKind() == BuiltinType::Long &&
3664            ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3665          PointeeTy = IntTy;
3666    }
3667  }
3668}
3669
3670void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
3671                                        const FieldDecl *Field) {
3672  // We follow the behavior of gcc, expanding structures which are
3673  // directly pointed to, and expanding embedded structures. Note that
3674  // these rules are sufficient to prevent recursive encoding of the
3675  // same type.
3676  getObjCEncodingForTypeImpl(T, S, true, true, Field,
3677                             true /* outermost type */);
3678}
3679
3680static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
3681    switch (T->getAs<BuiltinType>()->getKind()) {
3682    default: assert(0 && "Unhandled builtin type kind");
3683    case BuiltinType::Void:       return 'v';
3684    case BuiltinType::Bool:       return 'B';
3685    case BuiltinType::Char_U:
3686    case BuiltinType::UChar:      return 'C';
3687    case BuiltinType::UShort:     return 'S';
3688    case BuiltinType::UInt:       return 'I';
3689    case BuiltinType::ULong:
3690        return
3691          (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'L' : 'Q';
3692    case BuiltinType::UInt128:    return 'T';
3693    case BuiltinType::ULongLong:  return 'Q';
3694    case BuiltinType::Char_S:
3695    case BuiltinType::SChar:      return 'c';
3696    case BuiltinType::Short:      return 's';
3697    case BuiltinType::WChar:
3698    case BuiltinType::Int:        return 'i';
3699    case BuiltinType::Long:
3700      return
3701        (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'l' : 'q';
3702    case BuiltinType::LongLong:   return 'q';
3703    case BuiltinType::Int128:     return 't';
3704    case BuiltinType::Float:      return 'f';
3705    case BuiltinType::Double:     return 'd';
3706    case BuiltinType::LongDouble: return 'D';
3707    }
3708}
3709
3710static void EncodeBitField(const ASTContext *Context, std::string& S,
3711                           QualType T, const FieldDecl *FD) {
3712  const Expr *E = FD->getBitWidth();
3713  assert(E && "bitfield width not there - getObjCEncodingForTypeImpl");
3714  ASTContext *Ctx = const_cast<ASTContext*>(Context);
3715  S += 'b';
3716  // The NeXT runtime encodes bit fields as b followed by the number of bits.
3717  // The GNU runtime requires more information; bitfields are encoded as b,
3718  // then the offset (in bits) of the first element, then the type of the
3719  // bitfield, then the size in bits.  For example, in this structure:
3720  //
3721  // struct
3722  // {
3723  //    int integer;
3724  //    int flags:2;
3725  // };
3726  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
3727  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
3728  // information is not especially sensible, but we're stuck with it for
3729  // compatibility with GCC, although providing it breaks anything that
3730  // actually uses runtime introspection and wants to work on both runtimes...
3731  if (!Ctx->getLangOptions().NeXTRuntime) {
3732    const RecordDecl *RD = FD->getParent();
3733    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
3734    // FIXME: This same linear search is also used in ExprConstant - it might
3735    // be better if the FieldDecl stored its offset.  We'd be increasing the
3736    // size of the object slightly, but saving some time every time it is used.
3737    unsigned i = 0;
3738    for (RecordDecl::field_iterator Field = RD->field_begin(),
3739                                 FieldEnd = RD->field_end();
3740         Field != FieldEnd; (void)++Field, ++i) {
3741      if (*Field == FD)
3742        break;
3743    }
3744    S += llvm::utostr(RL.getFieldOffset(i));
3745    S += ObjCEncodingForPrimitiveKind(Context, T);
3746  }
3747  unsigned N = E->EvaluateAsInt(*Ctx).getZExtValue();
3748  S += llvm::utostr(N);
3749}
3750
3751// FIXME: Use SmallString for accumulating string.
3752void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
3753                                            bool ExpandPointedToStructures,
3754                                            bool ExpandStructures,
3755                                            const FieldDecl *FD,
3756                                            bool OutermostType,
3757                                            bool EncodingProperty) {
3758  if (T->getAs<BuiltinType>()) {
3759    if (FD && FD->isBitField())
3760      return EncodeBitField(this, S, T, FD);
3761    S += ObjCEncodingForPrimitiveKind(this, T);
3762    return;
3763  }
3764
3765  if (const ComplexType *CT = T->getAs<ComplexType>()) {
3766    S += 'j';
3767    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
3768                               false);
3769    return;
3770  }
3771
3772  // encoding for pointer or r3eference types.
3773  QualType PointeeTy;
3774  if (const PointerType *PT = T->getAs<PointerType>()) {
3775    if (PT->isObjCSelType()) {
3776      S += ':';
3777      return;
3778    }
3779    PointeeTy = PT->getPointeeType();
3780  }
3781  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3782    PointeeTy = RT->getPointeeType();
3783  if (!PointeeTy.isNull()) {
3784    bool isReadOnly = false;
3785    // For historical/compatibility reasons, the read-only qualifier of the
3786    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
3787    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
3788    // Also, do not emit the 'r' for anything but the outermost type!
3789    if (isa<TypedefType>(T.getTypePtr())) {
3790      if (OutermostType && T.isConstQualified()) {
3791        isReadOnly = true;
3792        S += 'r';
3793      }
3794    } else if (OutermostType) {
3795      QualType P = PointeeTy;
3796      while (P->getAs<PointerType>())
3797        P = P->getAs<PointerType>()->getPointeeType();
3798      if (P.isConstQualified()) {
3799        isReadOnly = true;
3800        S += 'r';
3801      }
3802    }
3803    if (isReadOnly) {
3804      // Another legacy compatibility encoding. Some ObjC qualifier and type
3805      // combinations need to be rearranged.
3806      // Rewrite "in const" from "nr" to "rn"
3807      if (llvm::StringRef(S).endswith("nr"))
3808        S.replace(S.end()-2, S.end(), "rn");
3809    }
3810
3811    if (PointeeTy->isCharType()) {
3812      // char pointer types should be encoded as '*' unless it is a
3813      // type that has been typedef'd to 'BOOL'.
3814      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
3815        S += '*';
3816        return;
3817      }
3818    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
3819      // GCC binary compat: Need to convert "struct objc_class *" to "#".
3820      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
3821        S += '#';
3822        return;
3823      }
3824      // GCC binary compat: Need to convert "struct objc_object *" to "@".
3825      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
3826        S += '@';
3827        return;
3828      }
3829      // fall through...
3830    }
3831    S += '^';
3832    getLegacyIntegralTypeEncoding(PointeeTy);
3833
3834    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
3835                               NULL);
3836    return;
3837  }
3838
3839  if (const ArrayType *AT =
3840      // Ignore type qualifiers etc.
3841        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
3842    if (isa<IncompleteArrayType>(AT)) {
3843      // Incomplete arrays are encoded as a pointer to the array element.
3844      S += '^';
3845
3846      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3847                                 false, ExpandStructures, FD);
3848    } else {
3849      S += '[';
3850
3851      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
3852        S += llvm::utostr(CAT->getSize().getZExtValue());
3853      else {
3854        //Variable length arrays are encoded as a regular array with 0 elements.
3855        assert(isa<VariableArrayType>(AT) && "Unknown array type!");
3856        S += '0';
3857      }
3858
3859      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3860                                 false, ExpandStructures, FD);
3861      S += ']';
3862    }
3863    return;
3864  }
3865
3866  if (T->getAs<FunctionType>()) {
3867    S += '?';
3868    return;
3869  }
3870
3871  if (const RecordType *RTy = T->getAs<RecordType>()) {
3872    RecordDecl *RDecl = RTy->getDecl();
3873    S += RDecl->isUnion() ? '(' : '{';
3874    // Anonymous structures print as '?'
3875    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
3876      S += II->getName();
3877      if (ClassTemplateSpecializationDecl *Spec
3878          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
3879        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
3880        std::string TemplateArgsStr
3881          = TemplateSpecializationType::PrintTemplateArgumentList(
3882                                            TemplateArgs.getFlatArgumentList(),
3883                                            TemplateArgs.flat_size(),
3884                                            (*this).PrintingPolicy);
3885
3886        S += TemplateArgsStr;
3887      }
3888    } else {
3889      S += '?';
3890    }
3891    if (ExpandStructures) {
3892      S += '=';
3893      for (RecordDecl::field_iterator Field = RDecl->field_begin(),
3894                                   FieldEnd = RDecl->field_end();
3895           Field != FieldEnd; ++Field) {
3896        if (FD) {
3897          S += '"';
3898          S += Field->getNameAsString();
3899          S += '"';
3900        }
3901
3902        // Special case bit-fields.
3903        if (Field->isBitField()) {
3904          getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
3905                                     (*Field));
3906        } else {
3907          QualType qt = Field->getType();
3908          getLegacyIntegralTypeEncoding(qt);
3909          getObjCEncodingForTypeImpl(qt, S, false, true,
3910                                     FD);
3911        }
3912      }
3913    }
3914    S += RDecl->isUnion() ? ')' : '}';
3915    return;
3916  }
3917
3918  if (T->isEnumeralType()) {
3919    if (FD && FD->isBitField())
3920      EncodeBitField(this, S, T, FD);
3921    else
3922      S += 'i';
3923    return;
3924  }
3925
3926  if (T->isBlockPointerType()) {
3927    S += "@?"; // Unlike a pointer-to-function, which is "^?".
3928    return;
3929  }
3930
3931  // Ignore protocol qualifiers when mangling at this level.
3932  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
3933    T = OT->getBaseType();
3934
3935  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
3936    // @encode(class_name)
3937    ObjCInterfaceDecl *OI = OIT->getDecl();
3938    S += '{';
3939    const IdentifierInfo *II = OI->getIdentifier();
3940    S += II->getName();
3941    S += '=';
3942    llvm::SmallVector<ObjCIvarDecl*, 32> Ivars;
3943    DeepCollectObjCIvars(OI, true, Ivars);
3944    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
3945      FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
3946      if (Field->isBitField())
3947        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
3948      else
3949        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
3950    }
3951    S += '}';
3952    return;
3953  }
3954
3955  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
3956    if (OPT->isObjCIdType()) {
3957      S += '@';
3958      return;
3959    }
3960
3961    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
3962      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
3963      // Since this is a binary compatibility issue, need to consult with runtime
3964      // folks. Fortunately, this is a *very* obsure construct.
3965      S += '#';
3966      return;
3967    }
3968
3969    if (OPT->isObjCQualifiedIdType()) {
3970      getObjCEncodingForTypeImpl(getObjCIdType(), S,
3971                                 ExpandPointedToStructures,
3972                                 ExpandStructures, FD);
3973      if (FD || EncodingProperty) {
3974        // Note that we do extended encoding of protocol qualifer list
3975        // Only when doing ivar or property encoding.
3976        S += '"';
3977        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3978             E = OPT->qual_end(); I != E; ++I) {
3979          S += '<';
3980          S += (*I)->getNameAsString();
3981          S += '>';
3982        }
3983        S += '"';
3984      }
3985      return;
3986    }
3987
3988    QualType PointeeTy = OPT->getPointeeType();
3989    if (!EncodingProperty &&
3990        isa<TypedefType>(PointeeTy.getTypePtr())) {
3991      // Another historical/compatibility reason.
3992      // We encode the underlying type which comes out as
3993      // {...};
3994      S += '^';
3995      getObjCEncodingForTypeImpl(PointeeTy, S,
3996                                 false, ExpandPointedToStructures,
3997                                 NULL);
3998      return;
3999    }
4000
4001    S += '@';
4002    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
4003      S += '"';
4004      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4005      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4006           E = OPT->qual_end(); I != E; ++I) {
4007        S += '<';
4008        S += (*I)->getNameAsString();
4009        S += '>';
4010      }
4011      S += '"';
4012    }
4013    return;
4014  }
4015
4016  // gcc just blithely ignores member pointers.
4017  // TODO: maybe there should be a mangling for these
4018  if (T->getAs<MemberPointerType>())
4019    return;
4020
4021  if (T->isVectorType()) {
4022    // This matches gcc's encoding, even though technically it is
4023    // insufficient.
4024    // FIXME. We should do a better job than gcc.
4025    return;
4026  }
4027
4028  assert(0 && "@encode for type not implemented!");
4029}
4030
4031void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4032                                                 std::string& S) const {
4033  if (QT & Decl::OBJC_TQ_In)
4034    S += 'n';
4035  if (QT & Decl::OBJC_TQ_Inout)
4036    S += 'N';
4037  if (QT & Decl::OBJC_TQ_Out)
4038    S += 'o';
4039  if (QT & Decl::OBJC_TQ_Bycopy)
4040    S += 'O';
4041  if (QT & Decl::OBJC_TQ_Byref)
4042    S += 'R';
4043  if (QT & Decl::OBJC_TQ_Oneway)
4044    S += 'V';
4045}
4046
4047void ASTContext::setBuiltinVaListType(QualType T) {
4048  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4049
4050  BuiltinVaListType = T;
4051}
4052
4053void ASTContext::setObjCIdType(QualType T) {
4054  ObjCIdTypedefType = T;
4055}
4056
4057void ASTContext::setObjCSelType(QualType T) {
4058  ObjCSelTypedefType = T;
4059}
4060
4061void ASTContext::setObjCProtoType(QualType QT) {
4062  ObjCProtoType = QT;
4063}
4064
4065void ASTContext::setObjCClassType(QualType T) {
4066  ObjCClassTypedefType = T;
4067}
4068
4069void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4070  assert(ObjCConstantStringType.isNull() &&
4071         "'NSConstantString' type already set!");
4072
4073  ObjCConstantStringType = getObjCInterfaceType(Decl);
4074}
4075
4076/// \brief Retrieve the template name that corresponds to a non-empty
4077/// lookup.
4078TemplateName ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4079                                                   UnresolvedSetIterator End) {
4080  unsigned size = End - Begin;
4081  assert(size > 1 && "set is not overloaded!");
4082
4083  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4084                          size * sizeof(FunctionTemplateDecl*));
4085  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4086
4087  NamedDecl **Storage = OT->getStorage();
4088  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4089    NamedDecl *D = *I;
4090    assert(isa<FunctionTemplateDecl>(D) ||
4091           (isa<UsingShadowDecl>(D) &&
4092            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4093    *Storage++ = D;
4094  }
4095
4096  return TemplateName(OT);
4097}
4098
4099/// \brief Retrieve the template name that represents a qualified
4100/// template name such as \c std::vector.
4101TemplateName ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4102                                                  bool TemplateKeyword,
4103                                                  TemplateDecl *Template) {
4104  // FIXME: Canonicalization?
4105  llvm::FoldingSetNodeID ID;
4106  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4107
4108  void *InsertPos = 0;
4109  QualifiedTemplateName *QTN =
4110    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4111  if (!QTN) {
4112    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4113    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4114  }
4115
4116  return TemplateName(QTN);
4117}
4118
4119/// \brief Retrieve the template name that represents a dependent
4120/// template name such as \c MetaFun::template apply.
4121TemplateName ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4122                                                  const IdentifierInfo *Name) {
4123  assert((!NNS || NNS->isDependent()) &&
4124         "Nested name specifier must be dependent");
4125
4126  llvm::FoldingSetNodeID ID;
4127  DependentTemplateName::Profile(ID, NNS, Name);
4128
4129  void *InsertPos = 0;
4130  DependentTemplateName *QTN =
4131    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4132
4133  if (QTN)
4134    return TemplateName(QTN);
4135
4136  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4137  if (CanonNNS == NNS) {
4138    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4139  } else {
4140    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4141    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4142    DependentTemplateName *CheckQTN =
4143      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4144    assert(!CheckQTN && "Dependent type name canonicalization broken");
4145    (void)CheckQTN;
4146  }
4147
4148  DependentTemplateNames.InsertNode(QTN, InsertPos);
4149  return TemplateName(QTN);
4150}
4151
4152/// \brief Retrieve the template name that represents a dependent
4153/// template name such as \c MetaFun::template operator+.
4154TemplateName
4155ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4156                                     OverloadedOperatorKind Operator) {
4157  assert((!NNS || NNS->isDependent()) &&
4158         "Nested name specifier must be dependent");
4159
4160  llvm::FoldingSetNodeID ID;
4161  DependentTemplateName::Profile(ID, NNS, Operator);
4162
4163  void *InsertPos = 0;
4164  DependentTemplateName *QTN
4165    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4166
4167  if (QTN)
4168    return TemplateName(QTN);
4169
4170  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4171  if (CanonNNS == NNS) {
4172    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4173  } else {
4174    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4175    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4176
4177    DependentTemplateName *CheckQTN
4178      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4179    assert(!CheckQTN && "Dependent template name canonicalization broken");
4180    (void)CheckQTN;
4181  }
4182
4183  DependentTemplateNames.InsertNode(QTN, InsertPos);
4184  return TemplateName(QTN);
4185}
4186
4187/// getFromTargetType - Given one of the integer types provided by
4188/// TargetInfo, produce the corresponding type. The unsigned @p Type
4189/// is actually a value of type @c TargetInfo::IntType.
4190CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4191  switch (Type) {
4192  case TargetInfo::NoInt: return CanQualType();
4193  case TargetInfo::SignedShort: return ShortTy;
4194  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4195  case TargetInfo::SignedInt: return IntTy;
4196  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4197  case TargetInfo::SignedLong: return LongTy;
4198  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4199  case TargetInfo::SignedLongLong: return LongLongTy;
4200  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4201  }
4202
4203  assert(false && "Unhandled TargetInfo::IntType value");
4204  return CanQualType();
4205}
4206
4207//===----------------------------------------------------------------------===//
4208//                        Type Predicates.
4209//===----------------------------------------------------------------------===//
4210
4211/// isObjCNSObjectType - Return true if this is an NSObject object using
4212/// NSObject attribute on a c-style pointer type.
4213/// FIXME - Make it work directly on types.
4214/// FIXME: Move to Type.
4215///
4216bool ASTContext::isObjCNSObjectType(QualType Ty) const {
4217  if (TypedefType *TDT = dyn_cast<TypedefType>(Ty)) {
4218    if (TypedefDecl *TD = TDT->getDecl())
4219      if (TD->getAttr<ObjCNSObjectAttr>())
4220        return true;
4221  }
4222  return false;
4223}
4224
4225/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4226/// garbage collection attribute.
4227///
4228Qualifiers::GC ASTContext::getObjCGCAttrKind(const QualType &Ty) const {
4229  Qualifiers::GC GCAttrs = Qualifiers::GCNone;
4230  if (getLangOptions().ObjC1 &&
4231      getLangOptions().getGCMode() != LangOptions::NonGC) {
4232    GCAttrs = Ty.getObjCGCAttr();
4233    // Default behavious under objective-c's gc is for objective-c pointers
4234    // (or pointers to them) be treated as though they were declared
4235    // as __strong.
4236    if (GCAttrs == Qualifiers::GCNone) {
4237      if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4238        GCAttrs = Qualifiers::Strong;
4239      else if (Ty->isPointerType())
4240        return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4241    }
4242    // Non-pointers have none gc'able attribute regardless of the attribute
4243    // set on them.
4244    else if (!Ty->isAnyPointerType() && !Ty->isBlockPointerType())
4245      return Qualifiers::GCNone;
4246  }
4247  return GCAttrs;
4248}
4249
4250//===----------------------------------------------------------------------===//
4251//                        Type Compatibility Testing
4252//===----------------------------------------------------------------------===//
4253
4254/// areCompatVectorTypes - Return true if the two specified vector types are
4255/// compatible.
4256static bool areCompatVectorTypes(const VectorType *LHS,
4257                                 const VectorType *RHS) {
4258  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
4259  return LHS->getElementType() == RHS->getElementType() &&
4260         LHS->getNumElements() == RHS->getNumElements();
4261}
4262
4263bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
4264                                          QualType SecondVec) {
4265  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
4266  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
4267
4268  if (hasSameUnqualifiedType(FirstVec, SecondVec))
4269    return true;
4270
4271  // AltiVec vectors types are identical to equivalent GCC vector types
4272  const VectorType *First = FirstVec->getAs<VectorType>();
4273  const VectorType *Second = SecondVec->getAs<VectorType>();
4274  if ((((First->getAltiVecSpecific() == VectorType::AltiVec) &&
4275        (Second->getAltiVecSpecific() == VectorType::NotAltiVec)) ||
4276       ((First->getAltiVecSpecific() == VectorType::NotAltiVec) &&
4277        (Second->getAltiVecSpecific() == VectorType::AltiVec))) &&
4278      hasSameType(First->getElementType(), Second->getElementType()) &&
4279      (First->getNumElements() == Second->getNumElements()))
4280    return true;
4281
4282  return false;
4283}
4284
4285//===----------------------------------------------------------------------===//
4286// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
4287//===----------------------------------------------------------------------===//
4288
4289/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
4290/// inheritance hierarchy of 'rProto'.
4291bool ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
4292                                                ObjCProtocolDecl *rProto) {
4293  if (lProto == rProto)
4294    return true;
4295  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
4296       E = rProto->protocol_end(); PI != E; ++PI)
4297    if (ProtocolCompatibleWithProtocol(lProto, *PI))
4298      return true;
4299  return false;
4300}
4301
4302/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
4303/// return true if lhs's protocols conform to rhs's protocol; false
4304/// otherwise.
4305bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
4306  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
4307    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
4308  return false;
4309}
4310
4311/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
4312/// Class<p1, ...>.
4313bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
4314                                                      QualType rhs) {
4315  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
4316  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4317  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
4318
4319  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4320       E = lhsQID->qual_end(); I != E; ++I) {
4321    bool match = false;
4322    ObjCProtocolDecl *lhsProto = *I;
4323    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4324         E = rhsOPT->qual_end(); J != E; ++J) {
4325      ObjCProtocolDecl *rhsProto = *J;
4326      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
4327        match = true;
4328        break;
4329      }
4330    }
4331    if (!match)
4332      return false;
4333  }
4334  return true;
4335}
4336
4337/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
4338/// ObjCQualifiedIDType.
4339bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
4340                                                   bool compare) {
4341  // Allow id<P..> and an 'id' or void* type in all cases.
4342  if (lhs->isVoidPointerType() ||
4343      lhs->isObjCIdType() || lhs->isObjCClassType())
4344    return true;
4345  else if (rhs->isVoidPointerType() ||
4346           rhs->isObjCIdType() || rhs->isObjCClassType())
4347    return true;
4348
4349  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
4350    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4351
4352    if (!rhsOPT) return false;
4353
4354    if (rhsOPT->qual_empty()) {
4355      // If the RHS is a unqualified interface pointer "NSString*",
4356      // make sure we check the class hierarchy.
4357      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4358        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4359             E = lhsQID->qual_end(); I != E; ++I) {
4360          // when comparing an id<P> on lhs with a static type on rhs,
4361          // see if static class implements all of id's protocols, directly or
4362          // through its super class and categories.
4363          if (!rhsID->ClassImplementsProtocol(*I, true))
4364            return false;
4365        }
4366      }
4367      // If there are no qualifiers and no interface, we have an 'id'.
4368      return true;
4369    }
4370    // Both the right and left sides have qualifiers.
4371    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4372         E = lhsQID->qual_end(); I != E; ++I) {
4373      ObjCProtocolDecl *lhsProto = *I;
4374      bool match = false;
4375
4376      // when comparing an id<P> on lhs with a static type on rhs,
4377      // see if static class implements all of id's protocols, directly or
4378      // through its super class and categories.
4379      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4380           E = rhsOPT->qual_end(); J != E; ++J) {
4381        ObjCProtocolDecl *rhsProto = *J;
4382        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4383            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4384          match = true;
4385          break;
4386        }
4387      }
4388      // If the RHS is a qualified interface pointer "NSString<P>*",
4389      // make sure we check the class hierarchy.
4390      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4391        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4392             E = lhsQID->qual_end(); I != E; ++I) {
4393          // when comparing an id<P> on lhs with a static type on rhs,
4394          // see if static class implements all of id's protocols, directly or
4395          // through its super class and categories.
4396          if (rhsID->ClassImplementsProtocol(*I, true)) {
4397            match = true;
4398            break;
4399          }
4400        }
4401      }
4402      if (!match)
4403        return false;
4404    }
4405
4406    return true;
4407  }
4408
4409  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
4410  assert(rhsQID && "One of the LHS/RHS should be id<x>");
4411
4412  if (const ObjCObjectPointerType *lhsOPT =
4413        lhs->getAsObjCInterfacePointerType()) {
4414    if (lhsOPT->qual_empty()) {
4415      bool match = false;
4416      if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
4417        for (ObjCObjectPointerType::qual_iterator I = rhsQID->qual_begin(),
4418             E = rhsQID->qual_end(); I != E; ++I) {
4419          // when comparing an id<P> on rhs with a static type on lhs,
4420          // static class must implement all of id's protocols directly or
4421          // indirectly through its super class.
4422          if (lhsID->ClassImplementsProtocol(*I, true)) {
4423            match = true;
4424            break;
4425          }
4426        }
4427        if (!match)
4428          return false;
4429      }
4430      return true;
4431    }
4432    // 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 lhs with a static type on rhs,
4439      // see if static class implements all of id's protocols, directly or
4440      // through its super class and categories.
4441      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4442           E = rhsQID->qual_end(); J != E; ++J) {
4443        ObjCProtocolDecl *rhsProto = *J;
4444        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4445            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4446          match = true;
4447          break;
4448        }
4449      }
4450      if (!match)
4451        return false;
4452    }
4453    return true;
4454  }
4455  return false;
4456}
4457
4458/// canAssignObjCInterfaces - Return true if the two interface types are
4459/// compatible for assignment from RHS to LHS.  This handles validation of any
4460/// protocol qualifiers on the LHS or RHS.
4461///
4462bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
4463                                         const ObjCObjectPointerType *RHSOPT) {
4464  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4465  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4466
4467  // If either type represents the built-in 'id' or 'Class' types, return true.
4468  if (LHS->isObjCUnqualifiedIdOrClass() ||
4469      RHS->isObjCUnqualifiedIdOrClass())
4470    return true;
4471
4472  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
4473    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4474                                             QualType(RHSOPT,0),
4475                                             false);
4476
4477  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
4478    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
4479                                                QualType(RHSOPT,0));
4480
4481  // If we have 2 user-defined types, fall into that path.
4482  if (LHS->getInterface() && RHS->getInterface())
4483    return canAssignObjCInterfaces(LHS, RHS);
4484
4485  return false;
4486}
4487
4488/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
4489/// for providing type-safty for objective-c pointers used to pass/return
4490/// arguments in block literals. When passed as arguments, passing 'A*' where
4491/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
4492/// not OK. For the return type, the opposite is not OK.
4493bool ASTContext::canAssignObjCInterfacesInBlockPointer(
4494                                         const ObjCObjectPointerType *LHSOPT,
4495                                         const ObjCObjectPointerType *RHSOPT) {
4496  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
4497    return true;
4498
4499  if (LHSOPT->isObjCBuiltinType()) {
4500    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
4501  }
4502
4503  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
4504    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4505                                             QualType(RHSOPT,0),
4506                                             false);
4507
4508  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
4509  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
4510  if (LHS && RHS)  { // We have 2 user-defined types.
4511    if (LHS != RHS) {
4512      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
4513        return false;
4514      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
4515        return true;
4516    }
4517    else
4518      return true;
4519  }
4520  return false;
4521}
4522
4523/// getIntersectionOfProtocols - This routine finds the intersection of set
4524/// of protocols inherited from two distinct objective-c pointer objects.
4525/// It is used to build composite qualifier list of the composite type of
4526/// the conditional expression involving two objective-c pointer objects.
4527static
4528void getIntersectionOfProtocols(ASTContext &Context,
4529                                const ObjCObjectPointerType *LHSOPT,
4530                                const ObjCObjectPointerType *RHSOPT,
4531      llvm::SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
4532
4533  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4534  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4535  assert(LHS->getInterface() && "LHS must have an interface base");
4536  assert(RHS->getInterface() && "RHS must have an interface base");
4537
4538  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
4539  unsigned LHSNumProtocols = LHS->getNumProtocols();
4540  if (LHSNumProtocols > 0)
4541    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
4542  else {
4543    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4544    Context.CollectInheritedProtocols(LHS->getInterface(),
4545                                      LHSInheritedProtocols);
4546    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
4547                                LHSInheritedProtocols.end());
4548  }
4549
4550  unsigned RHSNumProtocols = RHS->getNumProtocols();
4551  if (RHSNumProtocols > 0) {
4552    ObjCProtocolDecl **RHSProtocols =
4553      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
4554    for (unsigned i = 0; i < RHSNumProtocols; ++i)
4555      if (InheritedProtocolSet.count(RHSProtocols[i]))
4556        IntersectionOfProtocols.push_back(RHSProtocols[i]);
4557  }
4558  else {
4559    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
4560    Context.CollectInheritedProtocols(RHS->getInterface(),
4561                                      RHSInheritedProtocols);
4562    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4563         RHSInheritedProtocols.begin(),
4564         E = RHSInheritedProtocols.end(); I != E; ++I)
4565      if (InheritedProtocolSet.count((*I)))
4566        IntersectionOfProtocols.push_back((*I));
4567  }
4568}
4569
4570/// areCommonBaseCompatible - Returns common base class of the two classes if
4571/// one found. Note that this is O'2 algorithm. But it will be called as the
4572/// last type comparison in a ?-exp of ObjC pointer types before a
4573/// warning is issued. So, its invokation is extremely rare.
4574QualType ASTContext::areCommonBaseCompatible(
4575                                          const ObjCObjectPointerType *Lptr,
4576                                          const ObjCObjectPointerType *Rptr) {
4577  const ObjCObjectType *LHS = Lptr->getObjectType();
4578  const ObjCObjectType *RHS = Rptr->getObjectType();
4579  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
4580  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
4581  if (!LDecl || !RDecl)
4582    return QualType();
4583
4584  while ((LDecl = LDecl->getSuperClass())) {
4585    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
4586    if (canAssignObjCInterfaces(LHS, RHS)) {
4587      llvm::SmallVector<ObjCProtocolDecl *, 8> Protocols;
4588      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
4589
4590      QualType Result = QualType(LHS, 0);
4591      if (!Protocols.empty())
4592        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
4593      Result = getObjCObjectPointerType(Result);
4594      return Result;
4595    }
4596  }
4597
4598  return QualType();
4599}
4600
4601bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
4602                                         const ObjCObjectType *RHS) {
4603  assert(LHS->getInterface() && "LHS is not an interface type");
4604  assert(RHS->getInterface() && "RHS is not an interface type");
4605
4606  // Verify that the base decls are compatible: the RHS must be a subclass of
4607  // the LHS.
4608  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
4609    return false;
4610
4611  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
4612  // protocol qualified at all, then we are good.
4613  if (LHS->getNumProtocols() == 0)
4614    return true;
4615
4616  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't, then it
4617  // isn't a superset.
4618  if (RHS->getNumProtocols() == 0)
4619    return true;  // FIXME: should return false!
4620
4621  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
4622                                     LHSPE = LHS->qual_end();
4623       LHSPI != LHSPE; LHSPI++) {
4624    bool RHSImplementsProtocol = false;
4625
4626    // If the RHS doesn't implement the protocol on the left, the types
4627    // are incompatible.
4628    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
4629                                       RHSPE = RHS->qual_end();
4630         RHSPI != RHSPE; RHSPI++) {
4631      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
4632        RHSImplementsProtocol = true;
4633        break;
4634      }
4635    }
4636    // FIXME: For better diagnostics, consider passing back the protocol name.
4637    if (!RHSImplementsProtocol)
4638      return false;
4639  }
4640  // The RHS implements all protocols listed on the LHS.
4641  return true;
4642}
4643
4644bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
4645  // get the "pointed to" types
4646  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
4647  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
4648
4649  if (!LHSOPT || !RHSOPT)
4650    return false;
4651
4652  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
4653         canAssignObjCInterfaces(RHSOPT, LHSOPT);
4654}
4655
4656bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
4657  return canAssignObjCInterfaces(
4658                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
4659                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
4660}
4661
4662/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
4663/// both shall have the identically qualified version of a compatible type.
4664/// C99 6.2.7p1: Two types have compatible types if their types are the
4665/// same. See 6.7.[2,3,5] for additional rules.
4666bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
4667                                    bool CompareUnqualified) {
4668  if (getLangOptions().CPlusPlus)
4669    return hasSameType(LHS, RHS);
4670
4671  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
4672}
4673
4674bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
4675  return !mergeTypes(LHS, RHS, true).isNull();
4676}
4677
4678/// mergeTransparentUnionType - if T is a transparent union type and a member
4679/// of T is compatible with SubType, return the merged type, else return
4680/// QualType()
4681QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
4682                                               bool OfBlockPointer,
4683                                               bool Unqualified) {
4684  if (const RecordType *UT = T->getAsUnionType()) {
4685    RecordDecl *UD = UT->getDecl();
4686    if (UD->hasAttr<TransparentUnionAttr>()) {
4687      for (RecordDecl::field_iterator it = UD->field_begin(),
4688           itend = UD->field_end(); it != itend; ++it) {
4689        QualType ET = it->getType();
4690        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
4691        if (!MT.isNull())
4692          return MT;
4693      }
4694    }
4695  }
4696
4697  return QualType();
4698}
4699
4700/// mergeFunctionArgumentTypes - merge two types which appear as function
4701/// argument types
4702QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
4703                                                bool OfBlockPointer,
4704                                                bool Unqualified) {
4705  // GNU extension: two types are compatible if they appear as a function
4706  // argument, one of the types is a transparent union type and the other
4707  // type is compatible with a union member
4708  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
4709                                              Unqualified);
4710  if (!lmerge.isNull())
4711    return lmerge;
4712
4713  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
4714                                              Unqualified);
4715  if (!rmerge.isNull())
4716    return rmerge;
4717
4718  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
4719}
4720
4721QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
4722                                        bool OfBlockPointer,
4723                                        bool Unqualified) {
4724  const FunctionType *lbase = lhs->getAs<FunctionType>();
4725  const FunctionType *rbase = rhs->getAs<FunctionType>();
4726  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
4727  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
4728  bool allLTypes = true;
4729  bool allRTypes = true;
4730
4731  // Check return type
4732  QualType retType;
4733  if (OfBlockPointer)
4734    retType = mergeTypes(rbase->getResultType(), lbase->getResultType(), true,
4735                         Unqualified);
4736  else
4737   retType = mergeTypes(lbase->getResultType(), rbase->getResultType(),
4738                        false, Unqualified);
4739  if (retType.isNull()) return QualType();
4740
4741  if (Unqualified)
4742    retType = retType.getUnqualifiedType();
4743
4744  CanQualType LRetType = getCanonicalType(lbase->getResultType());
4745  CanQualType RRetType = getCanonicalType(rbase->getResultType());
4746  if (Unqualified) {
4747    LRetType = LRetType.getUnqualifiedType();
4748    RRetType = RRetType.getUnqualifiedType();
4749  }
4750
4751  if (getCanonicalType(retType) != LRetType)
4752    allLTypes = false;
4753  if (getCanonicalType(retType) != RRetType)
4754    allRTypes = false;
4755  // FIXME: double check this
4756  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
4757  //                           rbase->getRegParmAttr() != 0 &&
4758  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
4759  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
4760  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
4761  unsigned RegParm = lbaseInfo.getRegParm() == 0 ? rbaseInfo.getRegParm() :
4762      lbaseInfo.getRegParm();
4763  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
4764  if (NoReturn != lbaseInfo.getNoReturn() ||
4765      RegParm != lbaseInfo.getRegParm())
4766    allLTypes = false;
4767  if (NoReturn != rbaseInfo.getNoReturn() ||
4768      RegParm != rbaseInfo.getRegParm())
4769    allRTypes = false;
4770  CallingConv lcc = lbaseInfo.getCC();
4771  CallingConv rcc = rbaseInfo.getCC();
4772  // Compatible functions must have compatible calling conventions
4773  if (!isSameCallConv(lcc, rcc))
4774    return QualType();
4775
4776  if (lproto && rproto) { // two C99 style function prototypes
4777    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
4778           "C++ shouldn't be here");
4779    unsigned lproto_nargs = lproto->getNumArgs();
4780    unsigned rproto_nargs = rproto->getNumArgs();
4781
4782    // Compatible functions must have the same number of arguments
4783    if (lproto_nargs != rproto_nargs)
4784      return QualType();
4785
4786    // Variadic and non-variadic functions aren't compatible
4787    if (lproto->isVariadic() != rproto->isVariadic())
4788      return QualType();
4789
4790    if (lproto->getTypeQuals() != rproto->getTypeQuals())
4791      return QualType();
4792
4793    // Check argument compatibility
4794    llvm::SmallVector<QualType, 10> types;
4795    for (unsigned i = 0; i < lproto_nargs; i++) {
4796      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
4797      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
4798      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
4799                                                    OfBlockPointer,
4800                                                    Unqualified);
4801      if (argtype.isNull()) return QualType();
4802
4803      if (Unqualified)
4804        argtype = argtype.getUnqualifiedType();
4805
4806      types.push_back(argtype);
4807      if (Unqualified) {
4808        largtype = largtype.getUnqualifiedType();
4809        rargtype = rargtype.getUnqualifiedType();
4810      }
4811
4812      if (getCanonicalType(argtype) != getCanonicalType(largtype))
4813        allLTypes = false;
4814      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
4815        allRTypes = false;
4816    }
4817    if (allLTypes) return lhs;
4818    if (allRTypes) return rhs;
4819    return getFunctionType(retType, types.begin(), types.size(),
4820                           lproto->isVariadic(), lproto->getTypeQuals(),
4821                           false, false, 0, 0,
4822                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4823  }
4824
4825  if (lproto) allRTypes = false;
4826  if (rproto) allLTypes = false;
4827
4828  const FunctionProtoType *proto = lproto ? lproto : rproto;
4829  if (proto) {
4830    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
4831    if (proto->isVariadic()) return QualType();
4832    // Check that the types are compatible with the types that
4833    // would result from default argument promotions (C99 6.7.5.3p15).
4834    // The only types actually affected are promotable integer
4835    // types and floats, which would be passed as a different
4836    // type depending on whether the prototype is visible.
4837    unsigned proto_nargs = proto->getNumArgs();
4838    for (unsigned i = 0; i < proto_nargs; ++i) {
4839      QualType argTy = proto->getArgType(i);
4840
4841      // Look at the promotion type of enum types, since that is the type used
4842      // to pass enum values.
4843      if (const EnumType *Enum = argTy->getAs<EnumType>())
4844        argTy = Enum->getDecl()->getPromotionType();
4845
4846      if (argTy->isPromotableIntegerType() ||
4847          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
4848        return QualType();
4849    }
4850
4851    if (allLTypes) return lhs;
4852    if (allRTypes) return rhs;
4853    return getFunctionType(retType, proto->arg_type_begin(),
4854                           proto->getNumArgs(), proto->isVariadic(),
4855                           proto->getTypeQuals(),
4856                           false, false, 0, 0,
4857                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4858  }
4859
4860  if (allLTypes) return lhs;
4861  if (allRTypes) return rhs;
4862  FunctionType::ExtInfo Info(NoReturn, RegParm, lcc);
4863  return getFunctionNoProtoType(retType, Info);
4864}
4865
4866QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
4867                                bool OfBlockPointer,
4868                                bool Unqualified) {
4869  // C++ [expr]: If an expression initially has the type "reference to T", the
4870  // type is adjusted to "T" prior to any further analysis, the expression
4871  // designates the object or function denoted by the reference, and the
4872  // expression is an lvalue unless the reference is an rvalue reference and
4873  // the expression is a function call (possibly inside parentheses).
4874  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
4875  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
4876
4877  if (Unqualified) {
4878    LHS = LHS.getUnqualifiedType();
4879    RHS = RHS.getUnqualifiedType();
4880  }
4881
4882  QualType LHSCan = getCanonicalType(LHS),
4883           RHSCan = getCanonicalType(RHS);
4884
4885  // If two types are identical, they are compatible.
4886  if (LHSCan == RHSCan)
4887    return LHS;
4888
4889  // If the qualifiers are different, the types aren't compatible... mostly.
4890  Qualifiers LQuals = LHSCan.getLocalQualifiers();
4891  Qualifiers RQuals = RHSCan.getLocalQualifiers();
4892  if (LQuals != RQuals) {
4893    // If any of these qualifiers are different, we have a type
4894    // mismatch.
4895    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
4896        LQuals.getAddressSpace() != RQuals.getAddressSpace())
4897      return QualType();
4898
4899    // Exactly one GC qualifier difference is allowed: __strong is
4900    // okay if the other type has no GC qualifier but is an Objective
4901    // C object pointer (i.e. implicitly strong by default).  We fix
4902    // this by pretending that the unqualified type was actually
4903    // qualified __strong.
4904    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
4905    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
4906    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
4907
4908    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
4909      return QualType();
4910
4911    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
4912      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
4913    }
4914    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
4915      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
4916    }
4917    return QualType();
4918  }
4919
4920  // Okay, qualifiers are equal.
4921
4922  Type::TypeClass LHSClass = LHSCan->getTypeClass();
4923  Type::TypeClass RHSClass = RHSCan->getTypeClass();
4924
4925  // We want to consider the two function types to be the same for these
4926  // comparisons, just force one to the other.
4927  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
4928  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
4929
4930  // Same as above for arrays
4931  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
4932    LHSClass = Type::ConstantArray;
4933  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
4934    RHSClass = Type::ConstantArray;
4935
4936  // ObjCInterfaces are just specialized ObjCObjects.
4937  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
4938  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
4939
4940  // Canonicalize ExtVector -> Vector.
4941  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
4942  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
4943
4944  // If the canonical type classes don't match.
4945  if (LHSClass != RHSClass) {
4946    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
4947    // a signed integer type, or an unsigned integer type.
4948    // Compatibility is based on the underlying type, not the promotion
4949    // type.
4950    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
4951      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
4952        return RHS;
4953    }
4954    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
4955      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
4956        return LHS;
4957    }
4958
4959    return QualType();
4960  }
4961
4962  // The canonical type classes match.
4963  switch (LHSClass) {
4964#define TYPE(Class, Base)
4965#define ABSTRACT_TYPE(Class, Base)
4966#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
4967#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
4968#define DEPENDENT_TYPE(Class, Base) case Type::Class:
4969#include "clang/AST/TypeNodes.def"
4970    assert(false && "Non-canonical and dependent types shouldn't get here");
4971    return QualType();
4972
4973  case Type::LValueReference:
4974  case Type::RValueReference:
4975  case Type::MemberPointer:
4976    assert(false && "C++ should never be in mergeTypes");
4977    return QualType();
4978
4979  case Type::ObjCInterface:
4980  case Type::IncompleteArray:
4981  case Type::VariableArray:
4982  case Type::FunctionProto:
4983  case Type::ExtVector:
4984    assert(false && "Types are eliminated above");
4985    return QualType();
4986
4987  case Type::Pointer:
4988  {
4989    // Merge two pointer types, while trying to preserve typedef info
4990    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
4991    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
4992    if (Unqualified) {
4993      LHSPointee = LHSPointee.getUnqualifiedType();
4994      RHSPointee = RHSPointee.getUnqualifiedType();
4995    }
4996    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
4997                                     Unqualified);
4998    if (ResultType.isNull()) return QualType();
4999    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5000      return LHS;
5001    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5002      return RHS;
5003    return getPointerType(ResultType);
5004  }
5005  case Type::BlockPointer:
5006  {
5007    // Merge two block pointer types, while trying to preserve typedef info
5008    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
5009    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
5010    if (Unqualified) {
5011      LHSPointee = LHSPointee.getUnqualifiedType();
5012      RHSPointee = RHSPointee.getUnqualifiedType();
5013    }
5014    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
5015                                     Unqualified);
5016    if (ResultType.isNull()) return QualType();
5017    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
5018      return LHS;
5019    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
5020      return RHS;
5021    return getBlockPointerType(ResultType);
5022  }
5023  case Type::ConstantArray:
5024  {
5025    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
5026    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
5027    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
5028      return QualType();
5029
5030    QualType LHSElem = getAsArrayType(LHS)->getElementType();
5031    QualType RHSElem = getAsArrayType(RHS)->getElementType();
5032    if (Unqualified) {
5033      LHSElem = LHSElem.getUnqualifiedType();
5034      RHSElem = RHSElem.getUnqualifiedType();
5035    }
5036
5037    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
5038    if (ResultType.isNull()) return QualType();
5039    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5040      return LHS;
5041    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5042      return RHS;
5043    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
5044                                          ArrayType::ArraySizeModifier(), 0);
5045    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
5046                                          ArrayType::ArraySizeModifier(), 0);
5047    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
5048    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
5049    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5050      return LHS;
5051    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5052      return RHS;
5053    if (LVAT) {
5054      // FIXME: This isn't correct! But tricky to implement because
5055      // the array's size has to be the size of LHS, but the type
5056      // has to be different.
5057      return LHS;
5058    }
5059    if (RVAT) {
5060      // FIXME: This isn't correct! But tricky to implement because
5061      // the array's size has to be the size of RHS, but the type
5062      // has to be different.
5063      return RHS;
5064    }
5065    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
5066    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
5067    return getIncompleteArrayType(ResultType,
5068                                  ArrayType::ArraySizeModifier(), 0);
5069  }
5070  case Type::FunctionNoProto:
5071    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
5072  case Type::Record:
5073  case Type::Enum:
5074    return QualType();
5075  case Type::Builtin:
5076    // Only exactly equal builtin types are compatible, which is tested above.
5077    return QualType();
5078  case Type::Complex:
5079    // Distinct complex types are incompatible.
5080    return QualType();
5081  case Type::Vector:
5082    // FIXME: The merged type should be an ExtVector!
5083    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
5084                             RHSCan->getAs<VectorType>()))
5085      return LHS;
5086    return QualType();
5087  case Type::ObjCObject: {
5088    // Check if the types are assignment compatible.
5089    // FIXME: This should be type compatibility, e.g. whether
5090    // "LHS x; RHS x;" at global scope is legal.
5091    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
5092    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
5093    if (canAssignObjCInterfaces(LHSIface, RHSIface))
5094      return LHS;
5095
5096    return QualType();
5097  }
5098  case Type::ObjCObjectPointer: {
5099    if (OfBlockPointer) {
5100      if (canAssignObjCInterfacesInBlockPointer(
5101                                          LHS->getAs<ObjCObjectPointerType>(),
5102                                          RHS->getAs<ObjCObjectPointerType>()))
5103      return LHS;
5104      return QualType();
5105    }
5106    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
5107                                RHS->getAs<ObjCObjectPointerType>()))
5108      return LHS;
5109
5110    return QualType();
5111    }
5112  }
5113
5114  return QualType();
5115}
5116
5117/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
5118/// 'RHS' attributes and returns the merged version; including for function
5119/// return types.
5120QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
5121  QualType LHSCan = getCanonicalType(LHS),
5122  RHSCan = getCanonicalType(RHS);
5123  // If two types are identical, they are compatible.
5124  if (LHSCan == RHSCan)
5125    return LHS;
5126  if (RHSCan->isFunctionType()) {
5127    if (!LHSCan->isFunctionType())
5128      return QualType();
5129    QualType OldReturnType =
5130      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
5131    QualType NewReturnType =
5132      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
5133    QualType ResReturnType =
5134      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
5135    if (ResReturnType.isNull())
5136      return QualType();
5137    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
5138      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
5139      // In either case, use OldReturnType to build the new function type.
5140      const FunctionType *F = LHS->getAs<FunctionType>();
5141      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
5142        FunctionType::ExtInfo Info = getFunctionExtInfo(LHS);
5143        QualType ResultType
5144          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
5145                                  FPT->getNumArgs(), FPT->isVariadic(),
5146                                  FPT->getTypeQuals(),
5147                                  FPT->hasExceptionSpec(),
5148                                  FPT->hasAnyExceptionSpec(),
5149                                  FPT->getNumExceptions(),
5150                                  FPT->exception_begin(),
5151                                  Info);
5152        return ResultType;
5153      }
5154    }
5155    return QualType();
5156  }
5157
5158  // If the qualifiers are different, the types can still be merged.
5159  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5160  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5161  if (LQuals != RQuals) {
5162    // If any of these qualifiers are different, we have a type mismatch.
5163    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5164        LQuals.getAddressSpace() != RQuals.getAddressSpace())
5165      return QualType();
5166
5167    // Exactly one GC qualifier difference is allowed: __strong is
5168    // okay if the other type has no GC qualifier but is an Objective
5169    // C object pointer (i.e. implicitly strong by default).  We fix
5170    // this by pretending that the unqualified type was actually
5171    // qualified __strong.
5172    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5173    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5174    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5175
5176    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5177      return QualType();
5178
5179    if (GC_L == Qualifiers::Strong)
5180      return LHS;
5181    if (GC_R == Qualifiers::Strong)
5182      return RHS;
5183    return QualType();
5184  }
5185
5186  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
5187    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5188    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5189    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
5190    if (ResQT == LHSBaseQT)
5191      return LHS;
5192    if (ResQT == RHSBaseQT)
5193      return RHS;
5194  }
5195  return QualType();
5196}
5197
5198//===----------------------------------------------------------------------===//
5199//                         Integer Predicates
5200//===----------------------------------------------------------------------===//
5201
5202unsigned ASTContext::getIntWidth(QualType T) {
5203  if (EnumType *ET = dyn_cast<EnumType>(T))
5204    T = ET->getDecl()->getIntegerType();
5205  if (T->isBooleanType())
5206    return 1;
5207  // For builtin types, just use the standard type sizing method
5208  return (unsigned)getTypeSize(T);
5209}
5210
5211QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
5212  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
5213
5214  // Turn <4 x signed int> -> <4 x unsigned int>
5215  if (const VectorType *VTy = T->getAs<VectorType>())
5216    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
5217             VTy->getNumElements(), VTy->getAltiVecSpecific());
5218
5219  // For enums, we return the unsigned version of the base type.
5220  if (const EnumType *ETy = T->getAs<EnumType>())
5221    T = ETy->getDecl()->getIntegerType();
5222
5223  const BuiltinType *BTy = T->getAs<BuiltinType>();
5224  assert(BTy && "Unexpected signed integer type");
5225  switch (BTy->getKind()) {
5226  case BuiltinType::Char_S:
5227  case BuiltinType::SChar:
5228    return UnsignedCharTy;
5229  case BuiltinType::Short:
5230    return UnsignedShortTy;
5231  case BuiltinType::Int:
5232    return UnsignedIntTy;
5233  case BuiltinType::Long:
5234    return UnsignedLongTy;
5235  case BuiltinType::LongLong:
5236    return UnsignedLongLongTy;
5237  case BuiltinType::Int128:
5238    return UnsignedInt128Ty;
5239  default:
5240    assert(0 && "Unexpected signed integer type");
5241    return QualType();
5242  }
5243}
5244
5245ExternalASTSource::~ExternalASTSource() { }
5246
5247void ExternalASTSource::PrintStats() { }
5248
5249ASTMutationListener::~ASTMutationListener() { }
5250
5251
5252//===----------------------------------------------------------------------===//
5253//                          Builtin Type Computation
5254//===----------------------------------------------------------------------===//
5255
5256/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
5257/// pointer over the consumed characters.  This returns the resultant type.  If
5258/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
5259/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
5260/// a vector of "i*".
5261///
5262/// RequiresICE is filled in on return to indicate whether the value is required
5263/// to be an Integer Constant Expression.
5264static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
5265                                  ASTContext::GetBuiltinTypeError &Error,
5266                                  bool &RequiresICE,
5267                                  bool AllowTypeModifiers) {
5268  // Modifiers.
5269  int HowLong = 0;
5270  bool Signed = false, Unsigned = false;
5271  RequiresICE = false;
5272
5273  // Read the prefixed modifiers first.
5274  bool Done = false;
5275  while (!Done) {
5276    switch (*Str++) {
5277    default: Done = true; --Str; break;
5278    case 'I':
5279      RequiresICE = true;
5280      break;
5281    case 'S':
5282      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
5283      assert(!Signed && "Can't use 'S' modifier multiple times!");
5284      Signed = true;
5285      break;
5286    case 'U':
5287      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
5288      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
5289      Unsigned = true;
5290      break;
5291    case 'L':
5292      assert(HowLong <= 2 && "Can't have LLLL modifier");
5293      ++HowLong;
5294      break;
5295    }
5296  }
5297
5298  QualType Type;
5299
5300  // Read the base type.
5301  switch (*Str++) {
5302  default: assert(0 && "Unknown builtin type letter!");
5303  case 'v':
5304    assert(HowLong == 0 && !Signed && !Unsigned &&
5305           "Bad modifiers used with 'v'!");
5306    Type = Context.VoidTy;
5307    break;
5308  case 'f':
5309    assert(HowLong == 0 && !Signed && !Unsigned &&
5310           "Bad modifiers used with 'f'!");
5311    Type = Context.FloatTy;
5312    break;
5313  case 'd':
5314    assert(HowLong < 2 && !Signed && !Unsigned &&
5315           "Bad modifiers used with 'd'!");
5316    if (HowLong)
5317      Type = Context.LongDoubleTy;
5318    else
5319      Type = Context.DoubleTy;
5320    break;
5321  case 's':
5322    assert(HowLong == 0 && "Bad modifiers used with 's'!");
5323    if (Unsigned)
5324      Type = Context.UnsignedShortTy;
5325    else
5326      Type = Context.ShortTy;
5327    break;
5328  case 'i':
5329    if (HowLong == 3)
5330      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
5331    else if (HowLong == 2)
5332      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
5333    else if (HowLong == 1)
5334      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
5335    else
5336      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
5337    break;
5338  case 'c':
5339    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
5340    if (Signed)
5341      Type = Context.SignedCharTy;
5342    else if (Unsigned)
5343      Type = Context.UnsignedCharTy;
5344    else
5345      Type = Context.CharTy;
5346    break;
5347  case 'b': // boolean
5348    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
5349    Type = Context.BoolTy;
5350    break;
5351  case 'z':  // size_t.
5352    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
5353    Type = Context.getSizeType();
5354    break;
5355  case 'F':
5356    Type = Context.getCFConstantStringType();
5357    break;
5358  case 'a':
5359    Type = Context.getBuiltinVaListType();
5360    assert(!Type.isNull() && "builtin va list type not initialized!");
5361    break;
5362  case 'A':
5363    // This is a "reference" to a va_list; however, what exactly
5364    // this means depends on how va_list is defined. There are two
5365    // different kinds of va_list: ones passed by value, and ones
5366    // passed by reference.  An example of a by-value va_list is
5367    // x86, where va_list is a char*. An example of by-ref va_list
5368    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
5369    // we want this argument to be a char*&; for x86-64, we want
5370    // it to be a __va_list_tag*.
5371    Type = Context.getBuiltinVaListType();
5372    assert(!Type.isNull() && "builtin va list type not initialized!");
5373    if (Type->isArrayType())
5374      Type = Context.getArrayDecayedType(Type);
5375    else
5376      Type = Context.getLValueReferenceType(Type);
5377    break;
5378  case 'V': {
5379    char *End;
5380    unsigned NumElements = strtoul(Str, &End, 10);
5381    assert(End != Str && "Missing vector size");
5382    Str = End;
5383
5384    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
5385                                             RequiresICE, false);
5386    assert(!RequiresICE && "Can't require vector ICE");
5387
5388    // TODO: No way to make AltiVec vectors in builtins yet.
5389    Type = Context.getVectorType(ElementType, NumElements,
5390                                 VectorType::NotAltiVec);
5391    break;
5392  }
5393  case 'X': {
5394    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
5395                                             false);
5396    assert(!RequiresICE && "Can't require complex ICE");
5397    Type = Context.getComplexType(ElementType);
5398    break;
5399  }
5400  case 'P':
5401    Type = Context.getFILEType();
5402    if (Type.isNull()) {
5403      Error = ASTContext::GE_Missing_stdio;
5404      return QualType();
5405    }
5406    break;
5407  case 'J':
5408    if (Signed)
5409      Type = Context.getsigjmp_bufType();
5410    else
5411      Type = Context.getjmp_bufType();
5412
5413    if (Type.isNull()) {
5414      Error = ASTContext::GE_Missing_setjmp;
5415      return QualType();
5416    }
5417    break;
5418  }
5419
5420  // If there are modifiers and if we're allowed to parse them, go for it.
5421  Done = !AllowTypeModifiers;
5422  while (!Done) {
5423    switch (char c = *Str++) {
5424    default: Done = true; --Str; break;
5425    case '*':
5426    case '&': {
5427      // Both pointers and references can have their pointee types
5428      // qualified with an address space.
5429      char *End;
5430      unsigned AddrSpace = strtoul(Str, &End, 10);
5431      if (End != Str && AddrSpace != 0) {
5432        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
5433        Str = End;
5434      }
5435      if (c == '*')
5436        Type = Context.getPointerType(Type);
5437      else
5438        Type = Context.getLValueReferenceType(Type);
5439      break;
5440    }
5441    // FIXME: There's no way to have a built-in with an rvalue ref arg.
5442    case 'C':
5443      Type = Type.withConst();
5444      break;
5445    case 'D':
5446      Type = Context.getVolatileType(Type);
5447      break;
5448    }
5449  }
5450
5451  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
5452         "Integer constant 'I' type must be an integer");
5453
5454  return Type;
5455}
5456
5457/// GetBuiltinType - Return the type for the specified builtin.
5458QualType ASTContext::GetBuiltinType(unsigned Id,
5459                                    GetBuiltinTypeError &Error,
5460                                    unsigned *IntegerConstantArgs) {
5461  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
5462
5463  llvm::SmallVector<QualType, 8> ArgTypes;
5464
5465  bool RequiresICE = false;
5466  Error = GE_None;
5467  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
5468                                       RequiresICE, true);
5469  if (Error != GE_None)
5470    return QualType();
5471
5472  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
5473
5474  while (TypeStr[0] && TypeStr[0] != '.') {
5475    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
5476    if (Error != GE_None)
5477      return QualType();
5478
5479    // If this argument is required to be an IntegerConstantExpression and the
5480    // caller cares, fill in the bitmask we return.
5481    if (RequiresICE && IntegerConstantArgs)
5482      *IntegerConstantArgs |= 1 << ArgTypes.size();
5483
5484    // Do array -> pointer decay.  The builtin should use the decayed type.
5485    if (Ty->isArrayType())
5486      Ty = getArrayDecayedType(Ty);
5487
5488    ArgTypes.push_back(Ty);
5489  }
5490
5491  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
5492         "'.' should only occur at end of builtin type list!");
5493
5494  // handle untyped/variadic arguments "T c99Style();" or "T cppStyle(...);".
5495  if (ArgTypes.size() == 0 && TypeStr[0] == '.')
5496    return getFunctionNoProtoType(ResType);
5497
5498  // FIXME: Should we create noreturn types?
5499  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(),
5500                         TypeStr[0] == '.', 0, false, false, 0, 0,
5501                         FunctionType::ExtInfo());
5502}
5503
5504QualType
5505ASTContext::UsualArithmeticConversionsType(QualType lhs, QualType rhs) {
5506  // Perform the usual unary conversions. We do this early so that
5507  // integral promotions to "int" can allow us to exit early, in the
5508  // lhs == rhs check. Also, for conversion purposes, we ignore any
5509  // qualifiers.  For example, "const float" and "float" are
5510  // equivalent.
5511  if (lhs->isPromotableIntegerType())
5512    lhs = getPromotedIntegerType(lhs);
5513  else
5514    lhs = lhs.getUnqualifiedType();
5515  if (rhs->isPromotableIntegerType())
5516    rhs = getPromotedIntegerType(rhs);
5517  else
5518    rhs = rhs.getUnqualifiedType();
5519
5520  // If both types are identical, no conversion is needed.
5521  if (lhs == rhs)
5522    return lhs;
5523
5524  // If either side is a non-arithmetic type (e.g. a pointer), we are done.
5525  // The caller can deal with this (e.g. pointer + int).
5526  if (!lhs->isArithmeticType() || !rhs->isArithmeticType())
5527    return lhs;
5528
5529  // At this point, we have two different arithmetic types.
5530
5531  // Handle complex types first (C99 6.3.1.8p1).
5532  if (lhs->isComplexType() || rhs->isComplexType()) {
5533    // if we have an integer operand, the result is the complex type.
5534    if (rhs->isIntegerType() || rhs->isComplexIntegerType()) {
5535      // convert the rhs to the lhs complex type.
5536      return lhs;
5537    }
5538    if (lhs->isIntegerType() || lhs->isComplexIntegerType()) {
5539      // convert the lhs to the rhs complex type.
5540      return rhs;
5541    }
5542    // This handles complex/complex, complex/float, or float/complex.
5543    // When both operands are complex, the shorter operand is converted to the
5544    // type of the longer, and that is the type of the result. This corresponds
5545    // to what is done when combining two real floating-point operands.
5546    // The fun begins when size promotion occur across type domains.
5547    // From H&S 6.3.4: When one operand is complex and the other is a real
5548    // floating-point type, the less precise type is converted, within it's
5549    // real or complex domain, to the precision of the other type. For example,
5550    // when combining a "long double" with a "double _Complex", the
5551    // "double _Complex" is promoted to "long double _Complex".
5552    int result = getFloatingTypeOrder(lhs, rhs);
5553
5554    if (result > 0) { // The left side is bigger, convert rhs.
5555      rhs = getFloatingTypeOfSizeWithinDomain(lhs, rhs);
5556    } else if (result < 0) { // The right side is bigger, convert lhs.
5557      lhs = getFloatingTypeOfSizeWithinDomain(rhs, lhs);
5558    }
5559    // At this point, lhs and rhs have the same rank/size. Now, make sure the
5560    // domains match. This is a requirement for our implementation, C99
5561    // does not require this promotion.
5562    if (lhs != rhs) { // Domains don't match, we have complex/float mix.
5563      if (lhs->isRealFloatingType()) { // handle "double, _Complex double".
5564        return rhs;
5565      } else { // handle "_Complex double, double".
5566        return lhs;
5567      }
5568    }
5569    return lhs; // The domain/size match exactly.
5570  }
5571  // Now handle "real" floating types (i.e. float, double, long double).
5572  if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) {
5573    // if we have an integer operand, the result is the real floating type.
5574    if (rhs->isIntegerType()) {
5575      // convert rhs to the lhs floating point type.
5576      return lhs;
5577    }
5578    if (rhs->isComplexIntegerType()) {
5579      // convert rhs to the complex floating point type.
5580      return getComplexType(lhs);
5581    }
5582    if (lhs->isIntegerType()) {
5583      // convert lhs to the rhs floating point type.
5584      return rhs;
5585    }
5586    if (lhs->isComplexIntegerType()) {
5587      // convert lhs to the complex floating point type.
5588      return getComplexType(rhs);
5589    }
5590    // We have two real floating types, float/complex combos were handled above.
5591    // Convert the smaller operand to the bigger result.
5592    int result = getFloatingTypeOrder(lhs, rhs);
5593    if (result > 0) // convert the rhs
5594      return lhs;
5595    assert(result < 0 && "illegal float comparison");
5596    return rhs;   // convert the lhs
5597  }
5598  if (lhs->isComplexIntegerType() || rhs->isComplexIntegerType()) {
5599    // Handle GCC complex int extension.
5600    const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType();
5601    const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType();
5602
5603    if (lhsComplexInt && rhsComplexInt) {
5604      if (getIntegerTypeOrder(lhsComplexInt->getElementType(),
5605                              rhsComplexInt->getElementType()) >= 0)
5606        return lhs; // convert the rhs
5607      return rhs;
5608    } else if (lhsComplexInt && rhs->isIntegerType()) {
5609      // convert the rhs to the lhs complex type.
5610      return lhs;
5611    } else if (rhsComplexInt && lhs->isIntegerType()) {
5612      // convert the lhs to the rhs complex type.
5613      return rhs;
5614    }
5615  }
5616  // Finally, we have two differing integer types.
5617  // The rules for this case are in C99 6.3.1.8
5618  int compare = getIntegerTypeOrder(lhs, rhs);
5619  bool lhsSigned = lhs->hasSignedIntegerRepresentation(),
5620       rhsSigned = rhs->hasSignedIntegerRepresentation();
5621  QualType destType;
5622  if (lhsSigned == rhsSigned) {
5623    // Same signedness; use the higher-ranked type
5624    destType = compare >= 0 ? lhs : rhs;
5625  } else if (compare != (lhsSigned ? 1 : -1)) {
5626    // The unsigned type has greater than or equal rank to the
5627    // signed type, so use the unsigned type
5628    destType = lhsSigned ? rhs : lhs;
5629  } else if (getIntWidth(lhs) != getIntWidth(rhs)) {
5630    // The two types are different widths; if we are here, that
5631    // means the signed type is larger than the unsigned type, so
5632    // use the signed type.
5633    destType = lhsSigned ? lhs : rhs;
5634  } else {
5635    // The signed type is higher-ranked than the unsigned type,
5636    // but isn't actually any bigger (like unsigned int and long
5637    // on most 32-bit systems).  Use the unsigned type corresponding
5638    // to the signed type.
5639    destType = getCorrespondingUnsignedType(lhsSigned ? lhs : rhs);
5640  }
5641  return destType;
5642}
5643
5644GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
5645  GVALinkage External = GVA_StrongExternal;
5646
5647  Linkage L = FD->getLinkage();
5648  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5649      FD->getType()->getLinkage() == UniqueExternalLinkage)
5650    L = UniqueExternalLinkage;
5651
5652  switch (L) {
5653  case NoLinkage:
5654  case InternalLinkage:
5655  case UniqueExternalLinkage:
5656    return GVA_Internal;
5657
5658  case ExternalLinkage:
5659    switch (FD->getTemplateSpecializationKind()) {
5660    case TSK_Undeclared:
5661    case TSK_ExplicitSpecialization:
5662      External = GVA_StrongExternal;
5663      break;
5664
5665    case TSK_ExplicitInstantiationDefinition:
5666      return GVA_ExplicitTemplateInstantiation;
5667
5668    case TSK_ExplicitInstantiationDeclaration:
5669    case TSK_ImplicitInstantiation:
5670      External = GVA_TemplateInstantiation;
5671      break;
5672    }
5673  }
5674
5675  if (!FD->isInlined())
5676    return External;
5677
5678  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
5679    // GNU or C99 inline semantics. Determine whether this symbol should be
5680    // externally visible.
5681    if (FD->isInlineDefinitionExternallyVisible())
5682      return External;
5683
5684    // C99 inline semantics, where the symbol is not externally visible.
5685    return GVA_C99Inline;
5686  }
5687
5688  // C++0x [temp.explicit]p9:
5689  //   [ Note: The intent is that an inline function that is the subject of
5690  //   an explicit instantiation declaration will still be implicitly
5691  //   instantiated when used so that the body can be considered for
5692  //   inlining, but that no out-of-line copy of the inline function would be
5693  //   generated in the translation unit. -- end note ]
5694  if (FD->getTemplateSpecializationKind()
5695                                       == TSK_ExplicitInstantiationDeclaration)
5696    return GVA_C99Inline;
5697
5698  return GVA_CXXInline;
5699}
5700
5701GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
5702  // If this is a static data member, compute the kind of template
5703  // specialization. Otherwise, this variable is not part of a
5704  // template.
5705  TemplateSpecializationKind TSK = TSK_Undeclared;
5706  if (VD->isStaticDataMember())
5707    TSK = VD->getTemplateSpecializationKind();
5708
5709  Linkage L = VD->getLinkage();
5710  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5711      VD->getType()->getLinkage() == UniqueExternalLinkage)
5712    L = UniqueExternalLinkage;
5713
5714  switch (L) {
5715  case NoLinkage:
5716  case InternalLinkage:
5717  case UniqueExternalLinkage:
5718    return GVA_Internal;
5719
5720  case ExternalLinkage:
5721    switch (TSK) {
5722    case TSK_Undeclared:
5723    case TSK_ExplicitSpecialization:
5724      return GVA_StrongExternal;
5725
5726    case TSK_ExplicitInstantiationDeclaration:
5727      llvm_unreachable("Variable should not be instantiated");
5728      // Fall through to treat this like any other instantiation.
5729
5730    case TSK_ExplicitInstantiationDefinition:
5731      return GVA_ExplicitTemplateInstantiation;
5732
5733    case TSK_ImplicitInstantiation:
5734      return GVA_TemplateInstantiation;
5735    }
5736  }
5737
5738  return GVA_StrongExternal;
5739}
5740
5741bool ASTContext::DeclMustBeEmitted(const Decl *D) {
5742  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
5743    if (!VD->isFileVarDecl())
5744      return false;
5745  } else if (!isa<FunctionDecl>(D))
5746    return false;
5747
5748  // Weak references don't produce any output by themselves.
5749  if (D->hasAttr<WeakRefAttr>())
5750    return false;
5751
5752  // Aliases and used decls are required.
5753  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
5754    return true;
5755
5756  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
5757    // Forward declarations aren't required.
5758    if (!FD->isThisDeclarationADefinition())
5759      return false;
5760
5761    // Constructors and destructors are required.
5762    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
5763      return true;
5764
5765    // The key function for a class is required.
5766    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
5767      const CXXRecordDecl *RD = MD->getParent();
5768      if (MD->isOutOfLine() && RD->isDynamicClass()) {
5769        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
5770        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
5771          return true;
5772      }
5773    }
5774
5775    GVALinkage Linkage = GetGVALinkageForFunction(FD);
5776
5777    // static, static inline, always_inline, and extern inline functions can
5778    // always be deferred.  Normal inline functions can be deferred in C99/C++.
5779    // Implicit template instantiations can also be deferred in C++.
5780    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
5781        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
5782      return false;
5783    return true;
5784  }
5785
5786  const VarDecl *VD = cast<VarDecl>(D);
5787  assert(VD->isFileVarDecl() && "Expected file scoped var");
5788
5789  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
5790    return false;
5791
5792  // Structs that have non-trivial constructors or destructors are required.
5793
5794  // FIXME: Handle references.
5795  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
5796    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
5797      if (RD->hasDefinition() &&
5798          (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()))
5799        return true;
5800    }
5801  }
5802
5803  GVALinkage L = GetGVALinkageForVariable(VD);
5804  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
5805    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
5806      return false;
5807  }
5808
5809  return true;
5810}
5811
5812CXXABI::~CXXABI() {}
5813