ASTContext.cpp revision 3a0be84b2aed8563150cdbd976a98838afa261eb 
1//===--- ASTContext.cpp - Context to hold long-lived AST nodes ------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements the ASTContext interface.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/AST/ASTContext.h"
15#include "clang/AST/CharUnits.h"
16#include "clang/AST/DeclCXX.h"
17#include "clang/AST/DeclObjC.h"
18#include "clang/AST/DeclTemplate.h"
19#include "clang/AST/TypeLoc.h"
20#include "clang/AST/Expr.h"
21#include "clang/AST/ExprCXX.h"
22#include "clang/AST/ExternalASTSource.h"
23#include "clang/AST/RecordLayout.h"
24#include "clang/Basic/Builtins.h"
25#include "clang/Basic/SourceManager.h"
26#include "clang/Basic/TargetInfo.h"
27#include "llvm/ADT/SmallString.h"
28#include "llvm/ADT/StringExtras.h"
29#include "llvm/Support/MathExtras.h"
30#include "llvm/Support/raw_ostream.h"
31#include "CXXABI.h"
32
33using namespace clang;
34
35unsigned ASTContext::NumImplicitDefaultConstructors;
36unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
37unsigned ASTContext::NumImplicitCopyConstructors;
38unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
39unsigned ASTContext::NumImplicitCopyAssignmentOperators;
40unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
41unsigned ASTContext::NumImplicitDestructors;
42unsigned ASTContext::NumImplicitDestructorsDeclared;
43
44enum FloatingRank {
45  FloatRank, DoubleRank, LongDoubleRank
46};
47
48void
49ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
50                                               TemplateTemplateParmDecl *Parm) {
51  ID.AddInteger(Parm->getDepth());
52  ID.AddInteger(Parm->getPosition());
53  // FIXME: Parameter pack
54
55  TemplateParameterList *Params = Parm->getTemplateParameters();
56  ID.AddInteger(Params->size());
57  for (TemplateParameterList::const_iterator P = Params->begin(),
58                                          PEnd = Params->end();
59       P != PEnd; ++P) {
60    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
61      ID.AddInteger(0);
62      ID.AddBoolean(TTP->isParameterPack());
63      continue;
64    }
65
66    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
67      ID.AddInteger(1);
68      // FIXME: Parameter pack
69      ID.AddPointer(NTTP->getType().getAsOpaquePtr());
70      continue;
71    }
72
73    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
74    ID.AddInteger(2);
75    Profile(ID, TTP);
76  }
77}
78
79TemplateTemplateParmDecl *
80ASTContext::getCanonicalTemplateTemplateParmDecl(
81                                                 TemplateTemplateParmDecl *TTP) {
82  // Check if we already have a canonical template template parameter.
83  llvm::FoldingSetNodeID ID;
84  CanonicalTemplateTemplateParm::Profile(ID, TTP);
85  void *InsertPos = 0;
86  CanonicalTemplateTemplateParm *Canonical
87    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
88  if (Canonical)
89    return Canonical->getParam();
90
91  // Build a canonical template parameter list.
92  TemplateParameterList *Params = TTP->getTemplateParameters();
93  llvm::SmallVector<NamedDecl *, 4> CanonParams;
94  CanonParams.reserve(Params->size());
95  for (TemplateParameterList::const_iterator P = Params->begin(),
96                                          PEnd = Params->end();
97       P != PEnd; ++P) {
98    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
99      CanonParams.push_back(
100                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
101                                               SourceLocation(), TTP->getDepth(),
102                                               TTP->getIndex(), 0, false,
103                                               TTP->isParameterPack()));
104    else if (NonTypeTemplateParmDecl *NTTP
105             = dyn_cast<NonTypeTemplateParmDecl>(*P))
106      CanonParams.push_back(
107            NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
108                                            SourceLocation(), NTTP->getDepth(),
109                                            NTTP->getPosition(), 0,
110                                            getCanonicalType(NTTP->getType()),
111                                            0));
112    else
113      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
114                                           cast<TemplateTemplateParmDecl>(*P)));
115  }
116
117  TemplateTemplateParmDecl *CanonTTP
118    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
119                                       SourceLocation(), TTP->getDepth(),
120                                       TTP->getPosition(), 0,
121                         TemplateParameterList::Create(*this, SourceLocation(),
122                                                       SourceLocation(),
123                                                       CanonParams.data(),
124                                                       CanonParams.size(),
125                                                       SourceLocation()));
126
127  // Get the new insert position for the node we care about.
128  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
129  assert(Canonical == 0 && "Shouldn't be in the map!");
130  (void)Canonical;
131
132  // Create the canonical template template parameter entry.
133  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
134  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
135  return CanonTTP;
136}
137
138CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
139  if (!LangOpts.CPlusPlus) return 0;
140
141  switch (T.getCXXABI()) {
142  case CXXABI_ARM:
143    return CreateARMCXXABI(*this);
144  case CXXABI_Itanium:
145    return CreateItaniumCXXABI(*this);
146  case CXXABI_Microsoft:
147    return CreateMicrosoftCXXABI(*this);
148  }
149  return 0;
150}
151
152ASTContext::ASTContext(const LangOptions& LOpts, SourceManager &SM,
153                       const TargetInfo &t,
154                       IdentifierTable &idents, SelectorTable &sels,
155                       Builtin::Context &builtins,
156                       unsigned size_reserve) :
157  TemplateSpecializationTypes(this_()),
158  DependentTemplateSpecializationTypes(this_()),
159  GlobalNestedNameSpecifier(0), IsInt128Installed(false),
160  CFConstantStringTypeDecl(0), NSConstantStringTypeDecl(0),
161  ObjCFastEnumerationStateTypeDecl(0), FILEDecl(0), jmp_bufDecl(0),
162  sigjmp_bufDecl(0), BlockDescriptorType(0), BlockDescriptorExtendedType(0),
163  NullTypeSourceInfo(QualType()),
164  SourceMgr(SM), LangOpts(LOpts), ABI(createCXXABI(t)), Target(t),
165  Idents(idents), Selectors(sels),
166  BuiltinInfo(builtins),
167  DeclarationNames(*this),
168  ExternalSource(0), PrintingPolicy(LOpts),
169  LastSDM(0, 0),
170  UniqueBlockByRefTypeID(0), UniqueBlockParmTypeID(0) {
171  ObjCIdRedefinitionType = QualType();
172  ObjCClassRedefinitionType = QualType();
173  ObjCSelRedefinitionType = QualType();
174  if (size_reserve > 0) Types.reserve(size_reserve);
175  TUDecl = TranslationUnitDecl::Create(*this);
176  InitBuiltinTypes();
177}
178
179ASTContext::~ASTContext() {
180  // Release the DenseMaps associated with DeclContext objects.
181  // FIXME: Is this the ideal solution?
182  ReleaseDeclContextMaps();
183
184  // Call all of the deallocation functions.
185  for (unsigned I = 0, N = Deallocations.size(); I != N; ++I)
186    Deallocations[I].first(Deallocations[I].second);
187
188  // Release all of the memory associated with overridden C++ methods.
189  for (llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::iterator
190         OM = OverriddenMethods.begin(), OMEnd = OverriddenMethods.end();
191       OM != OMEnd; ++OM)
192    OM->second.Destroy();
193
194  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
195  // because they can contain DenseMaps.
196  for (llvm::DenseMap<const ObjCContainerDecl*,
197       const ASTRecordLayout*>::iterator
198       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
199    // Increment in loop to prevent using deallocated memory.
200    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
201      R->Destroy(*this);
202
203  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
204       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
205    // Increment in loop to prevent using deallocated memory.
206    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
207      R->Destroy(*this);
208  }
209
210  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
211                                                    AEnd = DeclAttrs.end();
212       A != AEnd; ++A)
213    A->second->~AttrVec();
214}
215
216void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
217  Deallocations.push_back(std::make_pair(Callback, Data));
218}
219
220void
221ASTContext::setExternalSource(llvm::OwningPtr<ExternalASTSource> &Source) {
222  ExternalSource.reset(Source.take());
223}
224
225void ASTContext::PrintStats() const {
226  fprintf(stderr, "*** AST Context Stats:\n");
227  fprintf(stderr, "  %d types total.\n", (int)Types.size());
228
229  unsigned counts[] = {
230#define TYPE(Name, Parent) 0,
231#define ABSTRACT_TYPE(Name, Parent)
232#include "clang/AST/TypeNodes.def"
233    0 // Extra
234  };
235
236  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
237    Type *T = Types[i];
238    counts[(unsigned)T->getTypeClass()]++;
239  }
240
241  unsigned Idx = 0;
242  unsigned TotalBytes = 0;
243#define TYPE(Name, Parent)                                              \
244  if (counts[Idx])                                                      \
245    fprintf(stderr, "    %d %s types\n", (int)counts[Idx], #Name);      \
246  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
247  ++Idx;
248#define ABSTRACT_TYPE(Name, Parent)
249#include "clang/AST/TypeNodes.def"
250
251  fprintf(stderr, "Total bytes = %d\n", int(TotalBytes));
252
253  // Implicit special member functions.
254  fprintf(stderr, "  %u/%u implicit default constructors created\n",
255          NumImplicitDefaultConstructorsDeclared,
256          NumImplicitDefaultConstructors);
257  fprintf(stderr, "  %u/%u implicit copy constructors created\n",
258          NumImplicitCopyConstructorsDeclared,
259          NumImplicitCopyConstructors);
260  fprintf(stderr, "  %u/%u implicit copy assignment operators created\n",
261          NumImplicitCopyAssignmentOperatorsDeclared,
262          NumImplicitCopyAssignmentOperators);
263  fprintf(stderr, "  %u/%u implicit destructors created\n",
264          NumImplicitDestructorsDeclared, NumImplicitDestructors);
265
266  if (ExternalSource.get()) {
267    fprintf(stderr, "\n");
268    ExternalSource->PrintStats();
269  }
270
271  BumpAlloc.PrintStats();
272}
273
274
275void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
276  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
277  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
278  Types.push_back(Ty);
279}
280
281void ASTContext::InitBuiltinTypes() {
282  assert(VoidTy.isNull() && "Context reinitialized?");
283
284  // C99 6.2.5p19.
285  InitBuiltinType(VoidTy,              BuiltinType::Void);
286
287  // C99 6.2.5p2.
288  InitBuiltinType(BoolTy,              BuiltinType::Bool);
289  // C99 6.2.5p3.
290  if (LangOpts.CharIsSigned)
291    InitBuiltinType(CharTy,            BuiltinType::Char_S);
292  else
293    InitBuiltinType(CharTy,            BuiltinType::Char_U);
294  // C99 6.2.5p4.
295  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
296  InitBuiltinType(ShortTy,             BuiltinType::Short);
297  InitBuiltinType(IntTy,               BuiltinType::Int);
298  InitBuiltinType(LongTy,              BuiltinType::Long);
299  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
300
301  // C99 6.2.5p6.
302  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
303  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
304  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
305  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
306  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
307
308  // C99 6.2.5p10.
309  InitBuiltinType(FloatTy,             BuiltinType::Float);
310  InitBuiltinType(DoubleTy,            BuiltinType::Double);
311  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
312
313  // GNU extension, 128-bit integers.
314  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
315  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
316
317  if (LangOpts.CPlusPlus) // C++ 3.9.1p5
318    InitBuiltinType(WCharTy,           BuiltinType::WChar);
319  else // C99
320    WCharTy = getFromTargetType(Target.getWCharType());
321
322  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
323    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
324  else // C99
325    Char16Ty = getFromTargetType(Target.getChar16Type());
326
327  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
328    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
329  else // C99
330    Char32Ty = getFromTargetType(Target.getChar32Type());
331
332  // Placeholder type for functions.
333  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
334
335  // Placeholder type for type-dependent expressions whose type is
336  // completely unknown. No code should ever check a type against
337  // DependentTy and users should never see it; however, it is here to
338  // help diagnose failures to properly check for type-dependent
339  // expressions.
340  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
341
342  // Placeholder type for C++0x auto declarations whose real type has
343  // not yet been deduced.
344  InitBuiltinType(UndeducedAutoTy, BuiltinType::UndeducedAuto);
345
346  // C99 6.2.5p11.
347  FloatComplexTy      = getComplexType(FloatTy);
348  DoubleComplexTy     = getComplexType(DoubleTy);
349  LongDoubleComplexTy = getComplexType(LongDoubleTy);
350
351  BuiltinVaListType = QualType();
352
353  // "Builtin" typedefs set by Sema::ActOnTranslationUnitScope().
354  ObjCIdTypedefType = QualType();
355  ObjCClassTypedefType = QualType();
356  ObjCSelTypedefType = QualType();
357
358  // Builtin types for 'id', 'Class', and 'SEL'.
359  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
360  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
361  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
362
363  ObjCConstantStringType = QualType();
364
365  // void * type
366  VoidPtrTy = getPointerType(VoidTy);
367
368  // nullptr type (C++0x 2.14.7)
369  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
370}
371
372Diagnostic &ASTContext::getDiagnostics() const {
373  return SourceMgr.getDiagnostics();
374}
375
376AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
377  AttrVec *&Result = DeclAttrs[D];
378  if (!Result) {
379    void *Mem = Allocate(sizeof(AttrVec));
380    Result = new (Mem) AttrVec;
381  }
382
383  return *Result;
384}
385
386/// \brief Erase the attributes corresponding to the given declaration.
387void ASTContext::eraseDeclAttrs(const Decl *D) {
388  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
389  if (Pos != DeclAttrs.end()) {
390    Pos->second->~AttrVec();
391    DeclAttrs.erase(Pos);
392  }
393}
394
395
396MemberSpecializationInfo *
397ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
398  assert(Var->isStaticDataMember() && "Not a static data member");
399  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
400    = InstantiatedFromStaticDataMember.find(Var);
401  if (Pos == InstantiatedFromStaticDataMember.end())
402    return 0;
403
404  return Pos->second;
405}
406
407void
408ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
409                                                TemplateSpecializationKind TSK,
410                                          SourceLocation PointOfInstantiation) {
411  assert(Inst->isStaticDataMember() && "Not a static data member");
412  assert(Tmpl->isStaticDataMember() && "Not a static data member");
413  assert(!InstantiatedFromStaticDataMember[Inst] &&
414         "Already noted what static data member was instantiated from");
415  InstantiatedFromStaticDataMember[Inst]
416    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
417}
418
419NamedDecl *
420ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
421  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
422    = InstantiatedFromUsingDecl.find(UUD);
423  if (Pos == InstantiatedFromUsingDecl.end())
424    return 0;
425
426  return Pos->second;
427}
428
429void
430ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
431  assert((isa<UsingDecl>(Pattern) ||
432          isa<UnresolvedUsingValueDecl>(Pattern) ||
433          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
434         "pattern decl is not a using decl");
435  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
436  InstantiatedFromUsingDecl[Inst] = Pattern;
437}
438
439UsingShadowDecl *
440ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
441  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
442    = InstantiatedFromUsingShadowDecl.find(Inst);
443  if (Pos == InstantiatedFromUsingShadowDecl.end())
444    return 0;
445
446  return Pos->second;
447}
448
449void
450ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
451                                               UsingShadowDecl *Pattern) {
452  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
453  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
454}
455
456FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
457  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
458    = InstantiatedFromUnnamedFieldDecl.find(Field);
459  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
460    return 0;
461
462  return Pos->second;
463}
464
465void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
466                                                     FieldDecl *Tmpl) {
467  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
468  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
469  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
470         "Already noted what unnamed field was instantiated from");
471
472  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
473}
474
475ASTContext::overridden_cxx_method_iterator
476ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
477  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
478    = OverriddenMethods.find(Method);
479  if (Pos == OverriddenMethods.end())
480    return 0;
481
482  return Pos->second.begin();
483}
484
485ASTContext::overridden_cxx_method_iterator
486ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
487  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
488    = OverriddenMethods.find(Method);
489  if (Pos == OverriddenMethods.end())
490    return 0;
491
492  return Pos->second.end();
493}
494
495unsigned
496ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
497  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
498    = OverriddenMethods.find(Method);
499  if (Pos == OverriddenMethods.end())
500    return 0;
501
502  return Pos->second.size();
503}
504
505void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
506                                     const CXXMethodDecl *Overridden) {
507  OverriddenMethods[Method].push_back(Overridden);
508}
509
510//===----------------------------------------------------------------------===//
511//                         Type Sizing and Analysis
512//===----------------------------------------------------------------------===//
513
514/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
515/// scalar floating point type.
516const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
517  const BuiltinType *BT = T->getAs<BuiltinType>();
518  assert(BT && "Not a floating point type!");
519  switch (BT->getKind()) {
520  default: assert(0 && "Not a floating point type!");
521  case BuiltinType::Float:      return Target.getFloatFormat();
522  case BuiltinType::Double:     return Target.getDoubleFormat();
523  case BuiltinType::LongDouble: return Target.getLongDoubleFormat();
524  }
525}
526
527/// getDeclAlign - Return a conservative estimate of the alignment of the
528/// specified decl.  Note that bitfields do not have a valid alignment, so
529/// this method will assert on them.
530/// If @p RefAsPointee, references are treated like their underlying type
531/// (for alignof), else they're treated like pointers (for CodeGen).
532CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) {
533  unsigned Align = Target.getCharWidth();
534
535  bool UseAlignAttrOnly = false;
536  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
537    Align = AlignFromAttr;
538
539    // __attribute__((aligned)) can increase or decrease alignment
540    // *except* on a struct or struct member, where it only increases
541    // alignment unless 'packed' is also specified.
542    //
543    // It is an error for [[align]] to decrease alignment, so we can
544    // ignore that possibility;  Sema should diagnose it.
545    if (isa<FieldDecl>(D)) {
546      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
547        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
548    } else {
549      UseAlignAttrOnly = true;
550    }
551  }
552
553  if (UseAlignAttrOnly) {
554    // ignore type of value
555  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
556    QualType T = VD->getType();
557    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
558      if (RefAsPointee)
559        T = RT->getPointeeType();
560      else
561        T = getPointerType(RT->getPointeeType());
562    }
563    if (!T->isIncompleteType() && !T->isFunctionType()) {
564      unsigned MinWidth = Target.getLargeArrayMinWidth();
565      unsigned ArrayAlign = Target.getLargeArrayAlign();
566      if (isa<VariableArrayType>(T) && MinWidth != 0)
567        Align = std::max(Align, ArrayAlign);
568      if (ConstantArrayType *CT = dyn_cast<ConstantArrayType>(T)) {
569        unsigned Size = getTypeSize(CT);
570        if (MinWidth != 0 && MinWidth <= Size)
571          Align = std::max(Align, ArrayAlign);
572      }
573      // Incomplete or function types default to 1.
574      while (isa<VariableArrayType>(T) || isa<IncompleteArrayType>(T))
575        T = cast<ArrayType>(T)->getElementType();
576
577      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
578    }
579    if (const FieldDecl *FD = dyn_cast<FieldDecl>(VD)) {
580      // In the case of a field in a packed struct, we want the minimum
581      // of the alignment of the field and the alignment of the struct.
582      Align = std::min(Align,
583        getPreferredTypeAlign(FD->getParent()->getTypeForDecl()));
584    }
585  }
586
587  return CharUnits::fromQuantity(Align / Target.getCharWidth());
588}
589
590std::pair<CharUnits, CharUnits>
591ASTContext::getTypeInfoInChars(const Type *T) {
592  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
593  return std::make_pair(CharUnits::fromQuantity(Info.first / getCharWidth()),
594                        CharUnits::fromQuantity(Info.second / getCharWidth()));
595}
596
597std::pair<CharUnits, CharUnits>
598ASTContext::getTypeInfoInChars(QualType T) {
599  return getTypeInfoInChars(T.getTypePtr());
600}
601
602/// getTypeSize - Return the size of the specified type, in bits.  This method
603/// does not work on incomplete types.
604///
605/// FIXME: Pointers into different addr spaces could have different sizes and
606/// alignment requirements: getPointerInfo should take an AddrSpace, this
607/// should take a QualType, &c.
608std::pair<uint64_t, unsigned>
609ASTContext::getTypeInfo(const Type *T) {
610  uint64_t Width=0;
611  unsigned Align=8;
612  switch (T->getTypeClass()) {
613#define TYPE(Class, Base)
614#define ABSTRACT_TYPE(Class, Base)
615#define NON_CANONICAL_TYPE(Class, Base)
616#define DEPENDENT_TYPE(Class, Base) case Type::Class:
617#include "clang/AST/TypeNodes.def"
618    assert(false && "Should not see dependent types");
619    break;
620
621  case Type::FunctionNoProto:
622  case Type::FunctionProto:
623    // GCC extension: alignof(function) = 32 bits
624    Width = 0;
625    Align = 32;
626    break;
627
628  case Type::IncompleteArray:
629  case Type::VariableArray:
630    Width = 0;
631    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
632    break;
633
634  case Type::ConstantArray: {
635    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
636
637    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
638    Width = EltInfo.first*CAT->getSize().getZExtValue();
639    Align = EltInfo.second;
640    break;
641  }
642  case Type::ExtVector:
643  case Type::Vector: {
644    const VectorType *VT = cast<VectorType>(T);
645    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
646    Width = EltInfo.first*VT->getNumElements();
647    Align = Width;
648    // If the alignment is not a power of 2, round up to the next power of 2.
649    // This happens for non-power-of-2 length vectors.
650    if (Align & (Align-1)) {
651      Align = llvm::NextPowerOf2(Align);
652      Width = llvm::RoundUpToAlignment(Width, Align);
653    }
654    break;
655  }
656
657  case Type::Builtin:
658    switch (cast<BuiltinType>(T)->getKind()) {
659    default: assert(0 && "Unknown builtin type!");
660    case BuiltinType::Void:
661      // GCC extension: alignof(void) = 8 bits.
662      Width = 0;
663      Align = 8;
664      break;
665
666    case BuiltinType::Bool:
667      Width = Target.getBoolWidth();
668      Align = Target.getBoolAlign();
669      break;
670    case BuiltinType::Char_S:
671    case BuiltinType::Char_U:
672    case BuiltinType::UChar:
673    case BuiltinType::SChar:
674      Width = Target.getCharWidth();
675      Align = Target.getCharAlign();
676      break;
677    case BuiltinType::WChar:
678      Width = Target.getWCharWidth();
679      Align = Target.getWCharAlign();
680      break;
681    case BuiltinType::Char16:
682      Width = Target.getChar16Width();
683      Align = Target.getChar16Align();
684      break;
685    case BuiltinType::Char32:
686      Width = Target.getChar32Width();
687      Align = Target.getChar32Align();
688      break;
689    case BuiltinType::UShort:
690    case BuiltinType::Short:
691      Width = Target.getShortWidth();
692      Align = Target.getShortAlign();
693      break;
694    case BuiltinType::UInt:
695    case BuiltinType::Int:
696      Width = Target.getIntWidth();
697      Align = Target.getIntAlign();
698      break;
699    case BuiltinType::ULong:
700    case BuiltinType::Long:
701      Width = Target.getLongWidth();
702      Align = Target.getLongAlign();
703      break;
704    case BuiltinType::ULongLong:
705    case BuiltinType::LongLong:
706      Width = Target.getLongLongWidth();
707      Align = Target.getLongLongAlign();
708      break;
709    case BuiltinType::Int128:
710    case BuiltinType::UInt128:
711      Width = 128;
712      Align = 128; // int128_t is 128-bit aligned on all targets.
713      break;
714    case BuiltinType::Float:
715      Width = Target.getFloatWidth();
716      Align = Target.getFloatAlign();
717      break;
718    case BuiltinType::Double:
719      Width = Target.getDoubleWidth();
720      Align = Target.getDoubleAlign();
721      break;
722    case BuiltinType::LongDouble:
723      Width = Target.getLongDoubleWidth();
724      Align = Target.getLongDoubleAlign();
725      break;
726    case BuiltinType::NullPtr:
727      Width = Target.getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
728      Align = Target.getPointerAlign(0); //   == sizeof(void*)
729      break;
730    case BuiltinType::ObjCId:
731    case BuiltinType::ObjCClass:
732    case BuiltinType::ObjCSel:
733      Width = Target.getPointerWidth(0);
734      Align = Target.getPointerAlign(0);
735      break;
736    }
737    break;
738  case Type::ObjCObjectPointer:
739    Width = Target.getPointerWidth(0);
740    Align = Target.getPointerAlign(0);
741    break;
742  case Type::BlockPointer: {
743    unsigned AS = cast<BlockPointerType>(T)->getPointeeType().getAddressSpace();
744    Width = Target.getPointerWidth(AS);
745    Align = Target.getPointerAlign(AS);
746    break;
747  }
748  case Type::LValueReference:
749  case Type::RValueReference: {
750    // alignof and sizeof should never enter this code path here, so we go
751    // the pointer route.
752    unsigned AS = cast<ReferenceType>(T)->getPointeeType().getAddressSpace();
753    Width = Target.getPointerWidth(AS);
754    Align = Target.getPointerAlign(AS);
755    break;
756  }
757  case Type::Pointer: {
758    unsigned AS = cast<PointerType>(T)->getPointeeType().getAddressSpace();
759    Width = Target.getPointerWidth(AS);
760    Align = Target.getPointerAlign(AS);
761    break;
762  }
763  case Type::MemberPointer: {
764    const MemberPointerType *MPT = cast<MemberPointerType>(T);
765    std::pair<uint64_t, unsigned> PtrDiffInfo =
766      getTypeInfo(getPointerDiffType());
767    Width = PtrDiffInfo.first * ABI->getMemberPointerSize(MPT);
768    Align = PtrDiffInfo.second;
769    break;
770  }
771  case Type::Complex: {
772    // Complex types have the same alignment as their elements, but twice the
773    // size.
774    std::pair<uint64_t, unsigned> EltInfo =
775      getTypeInfo(cast<ComplexType>(T)->getElementType());
776    Width = EltInfo.first*2;
777    Align = EltInfo.second;
778    break;
779  }
780  case Type::ObjCObject:
781    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
782  case Type::ObjCInterface: {
783    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
784    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
785    Width = Layout.getSize();
786    Align = Layout.getAlignment();
787    break;
788  }
789  case Type::Record:
790  case Type::Enum: {
791    const TagType *TT = cast<TagType>(T);
792
793    if (TT->getDecl()->isInvalidDecl()) {
794      Width = 1;
795      Align = 1;
796      break;
797    }
798
799    if (const EnumType *ET = dyn_cast<EnumType>(TT))
800      return getTypeInfo(ET->getDecl()->getIntegerType());
801
802    const RecordType *RT = cast<RecordType>(TT);
803    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
804    Width = Layout.getSize();
805    Align = Layout.getAlignment();
806    break;
807  }
808
809  case Type::SubstTemplateTypeParm:
810    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
811                       getReplacementType().getTypePtr());
812
813  case Type::Typedef: {
814    const TypedefDecl *Typedef = cast<TypedefType>(T)->getDecl();
815    std::pair<uint64_t, unsigned> Info
816      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
817    Align = std::max(Typedef->getMaxAlignment(), Info.second);
818    Width = Info.first;
819    break;
820  }
821
822  case Type::TypeOfExpr:
823    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
824                         .getTypePtr());
825
826  case Type::TypeOf:
827    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
828
829  case Type::Decltype:
830    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
831                        .getTypePtr());
832
833  case Type::Elaborated:
834    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
835
836  case Type::TemplateSpecialization:
837    assert(getCanonicalType(T) != T &&
838           "Cannot request the size of a dependent type");
839    // FIXME: this is likely to be wrong once we support template
840    // aliases, since a template alias could refer to a typedef that
841    // has an __aligned__ attribute on it.
842    return getTypeInfo(getCanonicalType(T));
843  }
844
845  assert(Align && (Align & (Align-1)) == 0 && "Alignment must be power of 2");
846  return std::make_pair(Width, Align);
847}
848
849/// getTypeSizeInChars - Return the size of the specified type, in characters.
850/// This method does not work on incomplete types.
851CharUnits ASTContext::getTypeSizeInChars(QualType T) {
852  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
853}
854CharUnits ASTContext::getTypeSizeInChars(const Type *T) {
855  return CharUnits::fromQuantity(getTypeSize(T) / getCharWidth());
856}
857
858/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
859/// characters. This method does not work on incomplete types.
860CharUnits ASTContext::getTypeAlignInChars(QualType T) {
861  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
862}
863CharUnits ASTContext::getTypeAlignInChars(const Type *T) {
864  return CharUnits::fromQuantity(getTypeAlign(T) / getCharWidth());
865}
866
867/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
868/// type for the current target in bits.  This can be different than the ABI
869/// alignment in cases where it is beneficial for performance to overalign
870/// a data type.
871unsigned ASTContext::getPreferredTypeAlign(const Type *T) {
872  unsigned ABIAlign = getTypeAlign(T);
873
874  // Double and long long should be naturally aligned if possible.
875  if (const ComplexType* CT = T->getAs<ComplexType>())
876    T = CT->getElementType().getTypePtr();
877  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
878      T->isSpecificBuiltinType(BuiltinType::LongLong))
879    return std::max(ABIAlign, (unsigned)getTypeSize(T));
880
881  return ABIAlign;
882}
883
884/// ShallowCollectObjCIvars -
885/// Collect all ivars, including those synthesized, in the current class.
886///
887void ASTContext::ShallowCollectObjCIvars(const ObjCInterfaceDecl *OI,
888                                 llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
889  // FIXME. This need be removed but there are two many places which
890  // assume const-ness of ObjCInterfaceDecl
891  ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
892  for (ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
893        Iv= Iv->getNextIvar())
894    Ivars.push_back(Iv);
895}
896
897/// DeepCollectObjCIvars -
898/// This routine first collects all declared, but not synthesized, ivars in
899/// super class and then collects all ivars, including those synthesized for
900/// current class. This routine is used for implementation of current class
901/// when all ivars, declared and synthesized are known.
902///
903void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
904                                      bool leafClass,
905                                llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
906  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
907    DeepCollectObjCIvars(SuperClass, false, Ivars);
908  if (!leafClass) {
909    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
910         E = OI->ivar_end(); I != E; ++I)
911      Ivars.push_back(*I);
912  }
913  else
914    ShallowCollectObjCIvars(OI, Ivars);
915}
916
917/// CollectInheritedProtocols - Collect all protocols in current class and
918/// those inherited by it.
919void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
920                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
921  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
922    // We can use protocol_iterator here instead of
923    // all_referenced_protocol_iterator since we are walking all categories.
924    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
925         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
926      ObjCProtocolDecl *Proto = (*P);
927      Protocols.insert(Proto);
928      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
929           PE = Proto->protocol_end(); P != PE; ++P) {
930        Protocols.insert(*P);
931        CollectInheritedProtocols(*P, Protocols);
932      }
933    }
934
935    // Categories of this Interface.
936    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
937         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
938      CollectInheritedProtocols(CDeclChain, Protocols);
939    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
940      while (SD) {
941        CollectInheritedProtocols(SD, Protocols);
942        SD = SD->getSuperClass();
943      }
944  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
945    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
946         PE = OC->protocol_end(); P != PE; ++P) {
947      ObjCProtocolDecl *Proto = (*P);
948      Protocols.insert(Proto);
949      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
950           PE = Proto->protocol_end(); P != PE; ++P)
951        CollectInheritedProtocols(*P, Protocols);
952    }
953  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
954    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
955         PE = OP->protocol_end(); P != PE; ++P) {
956      ObjCProtocolDecl *Proto = (*P);
957      Protocols.insert(Proto);
958      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
959           PE = Proto->protocol_end(); P != PE; ++P)
960        CollectInheritedProtocols(*P, Protocols);
961    }
962  }
963}
964
965unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) {
966  unsigned count = 0;
967  // Count ivars declared in class extension.
968  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
969       CDecl = CDecl->getNextClassExtension())
970    count += CDecl->ivar_size();
971
972  // Count ivar defined in this class's implementation.  This
973  // includes synthesized ivars.
974  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
975    count += ImplDecl->ivar_size();
976
977  return count;
978}
979
980/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
981ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
982  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
983    I = ObjCImpls.find(D);
984  if (I != ObjCImpls.end())
985    return cast<ObjCImplementationDecl>(I->second);
986  return 0;
987}
988/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
989ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
990  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
991    I = ObjCImpls.find(D);
992  if (I != ObjCImpls.end())
993    return cast<ObjCCategoryImplDecl>(I->second);
994  return 0;
995}
996
997/// \brief Set the implementation of ObjCInterfaceDecl.
998void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
999                           ObjCImplementationDecl *ImplD) {
1000  assert(IFaceD && ImplD && "Passed null params");
1001  ObjCImpls[IFaceD] = ImplD;
1002}
1003/// \brief Set the implementation of ObjCCategoryDecl.
1004void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1005                           ObjCCategoryImplDecl *ImplD) {
1006  assert(CatD && ImplD && "Passed null params");
1007  ObjCImpls[CatD] = ImplD;
1008}
1009
1010/// \brief Allocate an uninitialized TypeSourceInfo.
1011///
1012/// The caller should initialize the memory held by TypeSourceInfo using
1013/// the TypeLoc wrappers.
1014///
1015/// \param T the type that will be the basis for type source info. This type
1016/// should refer to how the declarator was written in source code, not to
1017/// what type semantic analysis resolved the declarator to.
1018TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1019                                                 unsigned DataSize) {
1020  if (!DataSize)
1021    DataSize = TypeLoc::getFullDataSizeForType(T);
1022  else
1023    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1024           "incorrect data size provided to CreateTypeSourceInfo!");
1025
1026  TypeSourceInfo *TInfo =
1027    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1028  new (TInfo) TypeSourceInfo(T);
1029  return TInfo;
1030}
1031
1032TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1033                                                     SourceLocation L) {
1034  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1035  DI->getTypeLoc().initialize(L);
1036  return DI;
1037}
1038
1039const ASTRecordLayout &
1040ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) {
1041  return getObjCLayout(D, 0);
1042}
1043
1044const ASTRecordLayout &
1045ASTContext::getASTObjCImplementationLayout(const ObjCImplementationDecl *D) {
1046  return getObjCLayout(D->getClassInterface(), D);
1047}
1048
1049//===----------------------------------------------------------------------===//
1050//                   Type creation/memoization methods
1051//===----------------------------------------------------------------------===//
1052
1053QualType ASTContext::getExtQualType(const Type *TypeNode, Qualifiers Quals) {
1054  unsigned Fast = Quals.getFastQualifiers();
1055  Quals.removeFastQualifiers();
1056
1057  // Check if we've already instantiated this type.
1058  llvm::FoldingSetNodeID ID;
1059  ExtQuals::Profile(ID, TypeNode, Quals);
1060  void *InsertPos = 0;
1061  if (ExtQuals *EQ = ExtQualNodes.FindNodeOrInsertPos(ID, InsertPos)) {
1062    assert(EQ->getQualifiers() == Quals);
1063    QualType T = QualType(EQ, Fast);
1064    return T;
1065  }
1066
1067  ExtQuals *New = new (*this, TypeAlignment) ExtQuals(*this, TypeNode, Quals);
1068  ExtQualNodes.InsertNode(New, InsertPos);
1069  QualType T = QualType(New, Fast);
1070  return T;
1071}
1072
1073QualType ASTContext::getVolatileType(QualType T) {
1074  QualType CanT = getCanonicalType(T);
1075  if (CanT.isVolatileQualified()) return T;
1076
1077  QualifierCollector Quals;
1078  const Type *TypeNode = Quals.strip(T);
1079  Quals.addVolatile();
1080
1081  return getExtQualType(TypeNode, Quals);
1082}
1083
1084QualType ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) {
1085  QualType CanT = getCanonicalType(T);
1086  if (CanT.getAddressSpace() == AddressSpace)
1087    return T;
1088
1089  // If we are composing extended qualifiers together, merge together
1090  // into one ExtQuals node.
1091  QualifierCollector Quals;
1092  const Type *TypeNode = Quals.strip(T);
1093
1094  // If this type already has an address space specified, it cannot get
1095  // another one.
1096  assert(!Quals.hasAddressSpace() &&
1097         "Type cannot be in multiple addr spaces!");
1098  Quals.addAddressSpace(AddressSpace);
1099
1100  return getExtQualType(TypeNode, Quals);
1101}
1102
1103QualType ASTContext::getObjCGCQualType(QualType T,
1104                                       Qualifiers::GC GCAttr) {
1105  QualType CanT = getCanonicalType(T);
1106  if (CanT.getObjCGCAttr() == GCAttr)
1107    return T;
1108
1109  if (T->isPointerType()) {
1110    QualType Pointee = T->getAs<PointerType>()->getPointeeType();
1111    if (Pointee->isAnyPointerType()) {
1112      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1113      return getPointerType(ResultType);
1114    }
1115  }
1116
1117  // If we are composing extended qualifiers together, merge together
1118  // into one ExtQuals node.
1119  QualifierCollector Quals;
1120  const Type *TypeNode = Quals.strip(T);
1121
1122  // If this type already has an ObjCGC specified, it cannot get
1123  // another one.
1124  assert(!Quals.hasObjCGCAttr() &&
1125         "Type cannot have multiple ObjCGCs!");
1126  Quals.addObjCGCAttr(GCAttr);
1127
1128  return getExtQualType(TypeNode, Quals);
1129}
1130
1131static QualType getExtFunctionType(ASTContext& Context, QualType T,
1132                                        const FunctionType::ExtInfo &Info) {
1133  QualType ResultType;
1134  if (const PointerType *Pointer = T->getAs<PointerType>()) {
1135    QualType Pointee = Pointer->getPointeeType();
1136    ResultType = getExtFunctionType(Context, Pointee, Info);
1137    if (ResultType == Pointee)
1138      return T;
1139
1140    ResultType = Context.getPointerType(ResultType);
1141  } else if (const BlockPointerType *BlockPointer
1142                                              = T->getAs<BlockPointerType>()) {
1143    QualType Pointee = BlockPointer->getPointeeType();
1144    ResultType = getExtFunctionType(Context, Pointee, Info);
1145    if (ResultType == Pointee)
1146      return T;
1147
1148    ResultType = Context.getBlockPointerType(ResultType);
1149  } else if (const MemberPointerType *MemberPointer
1150                                            = T->getAs<MemberPointerType>()) {
1151    QualType Pointee = MemberPointer->getPointeeType();
1152    ResultType = getExtFunctionType(Context, Pointee, Info);
1153    if (ResultType == Pointee)
1154      return T;
1155
1156    ResultType = Context.getMemberPointerType(ResultType,
1157                                              MemberPointer->getClass());
1158   } else if (const FunctionType *F = T->getAs<FunctionType>()) {
1159    if (F->getExtInfo() == Info)
1160      return T;
1161
1162    if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(F)) {
1163      ResultType = Context.getFunctionNoProtoType(FNPT->getResultType(),
1164                                                  Info);
1165    } else {
1166      const FunctionProtoType *FPT = cast<FunctionProtoType>(F);
1167      ResultType
1168        = Context.getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1169                                  FPT->getNumArgs(), FPT->isVariadic(),
1170                                  FPT->getTypeQuals(),
1171                                  FPT->hasExceptionSpec(),
1172                                  FPT->hasAnyExceptionSpec(),
1173                                  FPT->getNumExceptions(),
1174                                  FPT->exception_begin(),
1175                                  Info);
1176    }
1177  } else
1178    return T;
1179
1180  return Context.getQualifiedType(ResultType, T.getLocalQualifiers());
1181}
1182
1183QualType ASTContext::getNoReturnType(QualType T, bool AddNoReturn) {
1184  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1185  return getExtFunctionType(*this, T,
1186                                 Info.withNoReturn(AddNoReturn));
1187}
1188
1189QualType ASTContext::getCallConvType(QualType T, CallingConv CallConv) {
1190  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1191  return getExtFunctionType(*this, T,
1192                            Info.withCallingConv(CallConv));
1193}
1194
1195QualType ASTContext::getRegParmType(QualType T, unsigned RegParm) {
1196  FunctionType::ExtInfo Info = getFunctionExtInfo(T);
1197  return getExtFunctionType(*this, T,
1198                                 Info.withRegParm(RegParm));
1199}
1200
1201/// getComplexType - Return the uniqued reference to the type for a complex
1202/// number with the specified element type.
1203QualType ASTContext::getComplexType(QualType T) {
1204  // Unique pointers, to guarantee there is only one pointer of a particular
1205  // structure.
1206  llvm::FoldingSetNodeID ID;
1207  ComplexType::Profile(ID, T);
1208
1209  void *InsertPos = 0;
1210  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1211    return QualType(CT, 0);
1212
1213  // If the pointee type isn't canonical, this won't be a canonical type either,
1214  // so fill in the canonical type field.
1215  QualType Canonical;
1216  if (!T.isCanonical()) {
1217    Canonical = getComplexType(getCanonicalType(T));
1218
1219    // Get the new insert position for the node we care about.
1220    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1221    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1222  }
1223  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1224  Types.push_back(New);
1225  ComplexTypes.InsertNode(New, InsertPos);
1226  return QualType(New, 0);
1227}
1228
1229/// getPointerType - Return the uniqued reference to the type for a pointer to
1230/// the specified type.
1231QualType ASTContext::getPointerType(QualType T) {
1232  // Unique pointers, to guarantee there is only one pointer of a particular
1233  // structure.
1234  llvm::FoldingSetNodeID ID;
1235  PointerType::Profile(ID, T);
1236
1237  void *InsertPos = 0;
1238  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1239    return QualType(PT, 0);
1240
1241  // If the pointee type isn't canonical, this won't be a canonical type either,
1242  // so fill in the canonical type field.
1243  QualType Canonical;
1244  if (!T.isCanonical()) {
1245    Canonical = getPointerType(getCanonicalType(T));
1246
1247    // Get the new insert position for the node we care about.
1248    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1249    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1250  }
1251  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1252  Types.push_back(New);
1253  PointerTypes.InsertNode(New, InsertPos);
1254  return QualType(New, 0);
1255}
1256
1257/// getBlockPointerType - Return the uniqued reference to the type for
1258/// a pointer to the specified block.
1259QualType ASTContext::getBlockPointerType(QualType T) {
1260  assert(T->isFunctionType() && "block of function types only");
1261  // Unique pointers, to guarantee there is only one block of a particular
1262  // structure.
1263  llvm::FoldingSetNodeID ID;
1264  BlockPointerType::Profile(ID, T);
1265
1266  void *InsertPos = 0;
1267  if (BlockPointerType *PT =
1268        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1269    return QualType(PT, 0);
1270
1271  // If the block pointee type isn't canonical, this won't be a canonical
1272  // type either so fill in the canonical type field.
1273  QualType Canonical;
1274  if (!T.isCanonical()) {
1275    Canonical = getBlockPointerType(getCanonicalType(T));
1276
1277    // Get the new insert position for the node we care about.
1278    BlockPointerType *NewIP =
1279      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1280    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1281  }
1282  BlockPointerType *New
1283    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1284  Types.push_back(New);
1285  BlockPointerTypes.InsertNode(New, InsertPos);
1286  return QualType(New, 0);
1287}
1288
1289/// getLValueReferenceType - Return the uniqued reference to the type for an
1290/// lvalue reference to the specified type.
1291QualType ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) {
1292  // Unique pointers, to guarantee there is only one pointer of a particular
1293  // structure.
1294  llvm::FoldingSetNodeID ID;
1295  ReferenceType::Profile(ID, T, SpelledAsLValue);
1296
1297  void *InsertPos = 0;
1298  if (LValueReferenceType *RT =
1299        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1300    return QualType(RT, 0);
1301
1302  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1303
1304  // If the referencee type isn't canonical, this won't be a canonical type
1305  // either, so fill in the canonical type field.
1306  QualType Canonical;
1307  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1308    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1309    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1310
1311    // Get the new insert position for the node we care about.
1312    LValueReferenceType *NewIP =
1313      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1314    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1315  }
1316
1317  LValueReferenceType *New
1318    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1319                                                     SpelledAsLValue);
1320  Types.push_back(New);
1321  LValueReferenceTypes.InsertNode(New, InsertPos);
1322
1323  return QualType(New, 0);
1324}
1325
1326/// getRValueReferenceType - Return the uniqued reference to the type for an
1327/// rvalue reference to the specified type.
1328QualType ASTContext::getRValueReferenceType(QualType T) {
1329  // Unique pointers, to guarantee there is only one pointer of a particular
1330  // structure.
1331  llvm::FoldingSetNodeID ID;
1332  ReferenceType::Profile(ID, T, false);
1333
1334  void *InsertPos = 0;
1335  if (RValueReferenceType *RT =
1336        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1337    return QualType(RT, 0);
1338
1339  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1340
1341  // If the referencee type isn't canonical, this won't be a canonical type
1342  // either, so fill in the canonical type field.
1343  QualType Canonical;
1344  if (InnerRef || !T.isCanonical()) {
1345    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1346    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1347
1348    // Get the new insert position for the node we care about.
1349    RValueReferenceType *NewIP =
1350      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1351    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1352  }
1353
1354  RValueReferenceType *New
1355    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1356  Types.push_back(New);
1357  RValueReferenceTypes.InsertNode(New, InsertPos);
1358  return QualType(New, 0);
1359}
1360
1361/// getMemberPointerType - Return the uniqued reference to the type for a
1362/// member pointer to the specified type, in the specified class.
1363QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) {
1364  // Unique pointers, to guarantee there is only one pointer of a particular
1365  // structure.
1366  llvm::FoldingSetNodeID ID;
1367  MemberPointerType::Profile(ID, T, Cls);
1368
1369  void *InsertPos = 0;
1370  if (MemberPointerType *PT =
1371      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1372    return QualType(PT, 0);
1373
1374  // If the pointee or class type isn't canonical, this won't be a canonical
1375  // type either, so fill in the canonical type field.
1376  QualType Canonical;
1377  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
1378    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
1379
1380    // Get the new insert position for the node we care about.
1381    MemberPointerType *NewIP =
1382      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1383    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1384  }
1385  MemberPointerType *New
1386    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
1387  Types.push_back(New);
1388  MemberPointerTypes.InsertNode(New, InsertPos);
1389  return QualType(New, 0);
1390}
1391
1392/// getConstantArrayType - Return the unique reference to the type for an
1393/// array of the specified element type.
1394QualType ASTContext::getConstantArrayType(QualType EltTy,
1395                                          const llvm::APInt &ArySizeIn,
1396                                          ArrayType::ArraySizeModifier ASM,
1397                                          unsigned EltTypeQuals) {
1398  assert((EltTy->isDependentType() ||
1399          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
1400         "Constant array of VLAs is illegal!");
1401
1402  // Convert the array size into a canonical width matching the pointer size for
1403  // the target.
1404  llvm::APInt ArySize(ArySizeIn);
1405  ArySize.zextOrTrunc(Target.getPointerWidth(EltTy.getAddressSpace()));
1406
1407  llvm::FoldingSetNodeID ID;
1408  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, EltTypeQuals);
1409
1410  void *InsertPos = 0;
1411  if (ConstantArrayType *ATP =
1412      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1413    return QualType(ATP, 0);
1414
1415  // If the element type isn't canonical, this won't be a canonical type either,
1416  // so fill in the canonical type field.
1417  QualType Canonical;
1418  if (!EltTy.isCanonical()) {
1419    Canonical = getConstantArrayType(getCanonicalType(EltTy), ArySize,
1420                                     ASM, EltTypeQuals);
1421    // Get the new insert position for the node we care about.
1422    ConstantArrayType *NewIP =
1423      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1424    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1425  }
1426
1427  ConstantArrayType *New = new(*this,TypeAlignment)
1428    ConstantArrayType(EltTy, Canonical, ArySize, ASM, EltTypeQuals);
1429  ConstantArrayTypes.InsertNode(New, InsertPos);
1430  Types.push_back(New);
1431  return QualType(New, 0);
1432}
1433
1434/// getIncompleteArrayType - Returns a unique reference to the type for a
1435/// incomplete array of the specified element type.
1436QualType ASTContext::getUnknownSizeVariableArrayType(QualType Ty) {
1437  QualType ElemTy = getBaseElementType(Ty);
1438  DeclarationName Name;
1439  llvm::SmallVector<QualType, 8> ATypes;
1440  QualType ATy = Ty;
1441  while (const ArrayType *AT = getAsArrayType(ATy)) {
1442    ATypes.push_back(ATy);
1443    ATy = AT->getElementType();
1444  }
1445  for (int i = ATypes.size() - 1; i >= 0; i--) {
1446    if (const VariableArrayType *VAT = getAsVariableArrayType(ATypes[i])) {
1447      ElemTy = getVariableArrayType(ElemTy, /*ArraySize*/0, ArrayType::Star,
1448                                    0, VAT->getBracketsRange());
1449    }
1450    else if (const ConstantArrayType *CAT = getAsConstantArrayType(ATypes[i])) {
1451      llvm::APSInt ConstVal(CAT->getSize());
1452      ElemTy = getConstantArrayType(ElemTy, ConstVal, ArrayType::Normal, 0);
1453    }
1454    else if (getAsIncompleteArrayType(ATypes[i])) {
1455      ElemTy = getVariableArrayType(ElemTy, /*ArraySize*/0, ArrayType::Normal,
1456                                    0, SourceRange());
1457    }
1458    else
1459      assert(false && "DependentArrayType is seen");
1460  }
1461  return ElemTy;
1462}
1463
1464/// getVariableArrayDecayedType - Returns a vla type where known sizes
1465/// are replaced with [*]
1466QualType ASTContext::getVariableArrayDecayedType(QualType Ty) {
1467  if (Ty->isPointerType()) {
1468    QualType BaseType = Ty->getAs<PointerType>()->getPointeeType();
1469    if (isa<VariableArrayType>(BaseType)) {
1470      ArrayType *AT = dyn_cast<ArrayType>(BaseType);
1471      VariableArrayType *VAT = cast<VariableArrayType>(AT);
1472      if (VAT->getSizeExpr()) {
1473        Ty = getUnknownSizeVariableArrayType(BaseType);
1474        Ty = getPointerType(Ty);
1475      }
1476    }
1477  }
1478  return Ty;
1479}
1480
1481
1482/// getVariableArrayType - Returns a non-unique reference to the type for a
1483/// variable array of the specified element type.
1484QualType ASTContext::getVariableArrayType(QualType EltTy,
1485                                          Expr *NumElts,
1486                                          ArrayType::ArraySizeModifier ASM,
1487                                          unsigned EltTypeQuals,
1488                                          SourceRange Brackets) {
1489  // Since we don't unique expressions, it isn't possible to unique VLA's
1490  // that have an expression provided for their size.
1491  QualType CanonType;
1492
1493  if (!EltTy.isCanonical()) {
1494    if (NumElts)
1495      NumElts->Retain();
1496    CanonType = getVariableArrayType(getCanonicalType(EltTy), NumElts, ASM,
1497                                     EltTypeQuals, Brackets);
1498  }
1499
1500  VariableArrayType *New = new(*this, TypeAlignment)
1501    VariableArrayType(EltTy, CanonType, NumElts, ASM, EltTypeQuals, Brackets);
1502
1503  VariableArrayTypes.push_back(New);
1504  Types.push_back(New);
1505  return QualType(New, 0);
1506}
1507
1508/// getDependentSizedArrayType - Returns a non-unique reference to
1509/// the type for a dependently-sized array of the specified element
1510/// type.
1511QualType ASTContext::getDependentSizedArrayType(QualType EltTy,
1512                                                Expr *NumElts,
1513                                                ArrayType::ArraySizeModifier ASM,
1514                                                unsigned EltTypeQuals,
1515                                                SourceRange Brackets) {
1516  assert((!NumElts || NumElts->isTypeDependent() ||
1517          NumElts->isValueDependent()) &&
1518         "Size must be type- or value-dependent!");
1519
1520  void *InsertPos = 0;
1521  DependentSizedArrayType *Canon = 0;
1522  llvm::FoldingSetNodeID ID;
1523
1524  if (NumElts) {
1525    // Dependently-sized array types that do not have a specified
1526    // number of elements will have their sizes deduced from an
1527    // initializer.
1528    DependentSizedArrayType::Profile(ID, *this, getCanonicalType(EltTy), ASM,
1529                                     EltTypeQuals, NumElts);
1530
1531    Canon = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1532  }
1533
1534  DependentSizedArrayType *New;
1535  if (Canon) {
1536    // We already have a canonical version of this array type; use it as
1537    // the canonical type for a newly-built type.
1538    New = new (*this, TypeAlignment)
1539      DependentSizedArrayType(*this, EltTy, QualType(Canon, 0),
1540                              NumElts, ASM, EltTypeQuals, Brackets);
1541  } else {
1542    QualType CanonEltTy = getCanonicalType(EltTy);
1543    if (CanonEltTy == EltTy) {
1544      New = new (*this, TypeAlignment)
1545        DependentSizedArrayType(*this, EltTy, QualType(),
1546                                NumElts, ASM, EltTypeQuals, Brackets);
1547
1548      if (NumElts) {
1549        DependentSizedArrayType *CanonCheck
1550          = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1551        assert(!CanonCheck && "Dependent-sized canonical array type broken");
1552        (void)CanonCheck;
1553        DependentSizedArrayTypes.InsertNode(New, InsertPos);
1554      }
1555    } else {
1556      QualType Canon = getDependentSizedArrayType(CanonEltTy, NumElts,
1557                                                  ASM, EltTypeQuals,
1558                                                  SourceRange());
1559      New = new (*this, TypeAlignment)
1560        DependentSizedArrayType(*this, EltTy, Canon,
1561                                NumElts, ASM, EltTypeQuals, Brackets);
1562    }
1563  }
1564
1565  Types.push_back(New);
1566  return QualType(New, 0);
1567}
1568
1569QualType ASTContext::getIncompleteArrayType(QualType EltTy,
1570                                            ArrayType::ArraySizeModifier ASM,
1571                                            unsigned EltTypeQuals) {
1572  llvm::FoldingSetNodeID ID;
1573  IncompleteArrayType::Profile(ID, EltTy, ASM, EltTypeQuals);
1574
1575  void *InsertPos = 0;
1576  if (IncompleteArrayType *ATP =
1577       IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
1578    return QualType(ATP, 0);
1579
1580  // If the element type isn't canonical, this won't be a canonical type
1581  // either, so fill in the canonical type field.
1582  QualType Canonical;
1583
1584  if (!EltTy.isCanonical()) {
1585    Canonical = getIncompleteArrayType(getCanonicalType(EltTy),
1586                                       ASM, EltTypeQuals);
1587
1588    // Get the new insert position for the node we care about.
1589    IncompleteArrayType *NewIP =
1590      IncompleteArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
1591    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1592  }
1593
1594  IncompleteArrayType *New = new (*this, TypeAlignment)
1595    IncompleteArrayType(EltTy, Canonical, ASM, EltTypeQuals);
1596
1597  IncompleteArrayTypes.InsertNode(New, InsertPos);
1598  Types.push_back(New);
1599  return QualType(New, 0);
1600}
1601
1602/// getVectorType - Return the unique reference to a vector type of
1603/// the specified element type and size. VectorType must be a built-in type.
1604QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
1605                                   VectorType::AltiVecSpecific AltiVecSpec) {
1606  BuiltinType *BaseType;
1607
1608  BaseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1609  assert(BaseType != 0 && "getVectorType(): Expecting a built-in type");
1610
1611  // Check if we've already instantiated a vector of this type.
1612  llvm::FoldingSetNodeID ID;
1613  VectorType::Profile(ID, vecType, NumElts, Type::Vector, AltiVecSpec);
1614
1615  void *InsertPos = 0;
1616  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1617    return QualType(VTP, 0);
1618
1619  // If the element type isn't canonical, this won't be a canonical type either,
1620  // so fill in the canonical type field.
1621  QualType Canonical;
1622  if (!vecType.isCanonical()) {
1623    Canonical = getVectorType(getCanonicalType(vecType), NumElts,
1624      VectorType::NotAltiVec);
1625
1626    // Get the new insert position for the node we care about.
1627    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1628    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1629  }
1630  VectorType *New = new (*this, TypeAlignment)
1631    VectorType(vecType, NumElts, Canonical, AltiVecSpec);
1632  VectorTypes.InsertNode(New, InsertPos);
1633  Types.push_back(New);
1634  return QualType(New, 0);
1635}
1636
1637/// getExtVectorType - Return the unique reference to an extended vector type of
1638/// the specified element type and size. VectorType must be a built-in type.
1639QualType ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) {
1640  BuiltinType *baseType;
1641
1642  baseType = dyn_cast<BuiltinType>(getCanonicalType(vecType).getTypePtr());
1643  assert(baseType != 0 && "getExtVectorType(): Expecting a built-in type");
1644
1645  // Check if we've already instantiated a vector of this type.
1646  llvm::FoldingSetNodeID ID;
1647  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
1648                      VectorType::NotAltiVec);
1649  void *InsertPos = 0;
1650  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
1651    return QualType(VTP, 0);
1652
1653  // If the element type isn't canonical, this won't be a canonical type either,
1654  // so fill in the canonical type field.
1655  QualType Canonical;
1656  if (!vecType.isCanonical()) {
1657    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
1658
1659    // Get the new insert position for the node we care about.
1660    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1661    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1662  }
1663  ExtVectorType *New = new (*this, TypeAlignment)
1664    ExtVectorType(vecType, NumElts, Canonical);
1665  VectorTypes.InsertNode(New, InsertPos);
1666  Types.push_back(New);
1667  return QualType(New, 0);
1668}
1669
1670QualType ASTContext::getDependentSizedExtVectorType(QualType vecType,
1671                                                    Expr *SizeExpr,
1672                                                    SourceLocation AttrLoc) {
1673  llvm::FoldingSetNodeID ID;
1674  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
1675                                       SizeExpr);
1676
1677  void *InsertPos = 0;
1678  DependentSizedExtVectorType *Canon
1679    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1680  DependentSizedExtVectorType *New;
1681  if (Canon) {
1682    // We already have a canonical version of this array type; use it as
1683    // the canonical type for a newly-built type.
1684    New = new (*this, TypeAlignment)
1685      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
1686                                  SizeExpr, AttrLoc);
1687  } else {
1688    QualType CanonVecTy = getCanonicalType(vecType);
1689    if (CanonVecTy == vecType) {
1690      New = new (*this, TypeAlignment)
1691        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
1692                                    AttrLoc);
1693
1694      DependentSizedExtVectorType *CanonCheck
1695        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
1696      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
1697      (void)CanonCheck;
1698      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
1699    } else {
1700      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
1701                                                      SourceLocation());
1702      New = new (*this, TypeAlignment)
1703        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
1704    }
1705  }
1706
1707  Types.push_back(New);
1708  return QualType(New, 0);
1709}
1710
1711/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
1712///
1713QualType ASTContext::getFunctionNoProtoType(QualType ResultTy,
1714                                            const FunctionType::ExtInfo &Info) {
1715  const CallingConv CallConv = Info.getCC();
1716  // Unique functions, to guarantee there is only one function of a particular
1717  // structure.
1718  llvm::FoldingSetNodeID ID;
1719  FunctionNoProtoType::Profile(ID, ResultTy, Info);
1720
1721  void *InsertPos = 0;
1722  if (FunctionNoProtoType *FT =
1723        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1724    return QualType(FT, 0);
1725
1726  QualType Canonical;
1727  if (!ResultTy.isCanonical() ||
1728      getCanonicalCallConv(CallConv) != CallConv) {
1729    Canonical =
1730      getFunctionNoProtoType(getCanonicalType(ResultTy),
1731                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1732
1733    // Get the new insert position for the node we care about.
1734    FunctionNoProtoType *NewIP =
1735      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1736    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1737  }
1738
1739  FunctionNoProtoType *New = new (*this, TypeAlignment)
1740    FunctionNoProtoType(ResultTy, Canonical, Info);
1741  Types.push_back(New);
1742  FunctionNoProtoTypes.InsertNode(New, InsertPos);
1743  return QualType(New, 0);
1744}
1745
1746/// getFunctionType - Return a normal function type with a typed argument
1747/// list.  isVariadic indicates whether the argument list includes '...'.
1748QualType ASTContext::getFunctionType(QualType ResultTy,const QualType *ArgArray,
1749                                     unsigned NumArgs, bool isVariadic,
1750                                     unsigned TypeQuals, bool hasExceptionSpec,
1751                                     bool hasAnyExceptionSpec, unsigned NumExs,
1752                                     const QualType *ExArray,
1753                                     const FunctionType::ExtInfo &Info) {
1754
1755  const CallingConv CallConv= Info.getCC();
1756  // Unique functions, to guarantee there is only one function of a particular
1757  // structure.
1758  llvm::FoldingSetNodeID ID;
1759  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, isVariadic,
1760                             TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1761                             NumExs, ExArray, Info);
1762
1763  void *InsertPos = 0;
1764  if (FunctionProtoType *FTP =
1765        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
1766    return QualType(FTP, 0);
1767
1768  // Determine whether the type being created is already canonical or not.
1769  bool isCanonical = !hasExceptionSpec && ResultTy.isCanonical();
1770  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
1771    if (!ArgArray[i].isCanonicalAsParam())
1772      isCanonical = false;
1773
1774  // If this type isn't canonical, get the canonical version of it.
1775  // The exception spec is not part of the canonical type.
1776  QualType Canonical;
1777  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
1778    llvm::SmallVector<QualType, 16> CanonicalArgs;
1779    CanonicalArgs.reserve(NumArgs);
1780    for (unsigned i = 0; i != NumArgs; ++i)
1781      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
1782
1783    Canonical = getFunctionType(getCanonicalType(ResultTy),
1784                                CanonicalArgs.data(), NumArgs,
1785                                isVariadic, TypeQuals, false,
1786                                false, 0, 0,
1787                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
1788
1789    // Get the new insert position for the node we care about.
1790    FunctionProtoType *NewIP =
1791      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
1792    assert(NewIP == 0 && "Shouldn't be in the map!"); NewIP = NewIP;
1793  }
1794
1795  // FunctionProtoType objects are allocated with extra bytes after them
1796  // for two variable size arrays (for parameter and exception types) at the
1797  // end of them.
1798  FunctionProtoType *FTP =
1799    (FunctionProtoType*)Allocate(sizeof(FunctionProtoType) +
1800                                 NumArgs*sizeof(QualType) +
1801                                 NumExs*sizeof(QualType), TypeAlignment);
1802  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, isVariadic,
1803                              TypeQuals, hasExceptionSpec, hasAnyExceptionSpec,
1804                              ExArray, NumExs, Canonical, Info);
1805  Types.push_back(FTP);
1806  FunctionProtoTypes.InsertNode(FTP, InsertPos);
1807  return QualType(FTP, 0);
1808}
1809
1810#ifndef NDEBUG
1811static bool NeedsInjectedClassNameType(const RecordDecl *D) {
1812  if (!isa<CXXRecordDecl>(D)) return false;
1813  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
1814  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
1815    return true;
1816  if (RD->getDescribedClassTemplate() &&
1817      !isa<ClassTemplateSpecializationDecl>(RD))
1818    return true;
1819  return false;
1820}
1821#endif
1822
1823/// getInjectedClassNameType - Return the unique reference to the
1824/// injected class name type for the specified templated declaration.
1825QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
1826                                              QualType TST) {
1827  assert(NeedsInjectedClassNameType(Decl));
1828  if (Decl->TypeForDecl) {
1829    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1830  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDeclaration()) {
1831    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
1832    Decl->TypeForDecl = PrevDecl->TypeForDecl;
1833    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
1834  } else {
1835    Decl->TypeForDecl =
1836      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
1837    Types.push_back(Decl->TypeForDecl);
1838  }
1839  return QualType(Decl->TypeForDecl, 0);
1840}
1841
1842/// getTypeDeclType - Return the unique reference to the type for the
1843/// specified type declaration.
1844QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) {
1845  assert(Decl && "Passed null for Decl param");
1846  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
1847
1848  if (const TypedefDecl *Typedef = dyn_cast<TypedefDecl>(Decl))
1849    return getTypedefType(Typedef);
1850
1851  assert(!isa<TemplateTypeParmDecl>(Decl) &&
1852         "Template type parameter types are always available.");
1853
1854  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
1855    assert(!Record->getPreviousDeclaration() &&
1856           "struct/union has previous declaration");
1857    assert(!NeedsInjectedClassNameType(Record));
1858    return getRecordType(Record);
1859  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
1860    assert(!Enum->getPreviousDeclaration() &&
1861           "enum has previous declaration");
1862    return getEnumType(Enum);
1863  } else if (const UnresolvedUsingTypenameDecl *Using =
1864               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
1865    Decl->TypeForDecl = new (*this, TypeAlignment) UnresolvedUsingType(Using);
1866  } else
1867    llvm_unreachable("TypeDecl without a type?");
1868
1869  Types.push_back(Decl->TypeForDecl);
1870  return QualType(Decl->TypeForDecl, 0);
1871}
1872
1873/// getTypedefType - Return the unique reference to the type for the
1874/// specified typename decl.
1875QualType
1876ASTContext::getTypedefType(const TypedefDecl *Decl, QualType Canonical) {
1877  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1878
1879  if (Canonical.isNull())
1880    Canonical = getCanonicalType(Decl->getUnderlyingType());
1881  Decl->TypeForDecl = new(*this, TypeAlignment)
1882    TypedefType(Type::Typedef, Decl, Canonical);
1883  Types.push_back(Decl->TypeForDecl);
1884  return QualType(Decl->TypeForDecl, 0);
1885}
1886
1887QualType ASTContext::getRecordType(const RecordDecl *Decl) {
1888  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1889
1890  if (const RecordDecl *PrevDecl = Decl->getPreviousDeclaration())
1891    if (PrevDecl->TypeForDecl)
1892      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1893
1894  Decl->TypeForDecl = new (*this, TypeAlignment) RecordType(Decl);
1895  Types.push_back(Decl->TypeForDecl);
1896  return QualType(Decl->TypeForDecl, 0);
1897}
1898
1899QualType ASTContext::getEnumType(const EnumDecl *Decl) {
1900  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
1901
1902  if (const EnumDecl *PrevDecl = Decl->getPreviousDeclaration())
1903    if (PrevDecl->TypeForDecl)
1904      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
1905
1906  Decl->TypeForDecl = new (*this, TypeAlignment) EnumType(Decl);
1907  Types.push_back(Decl->TypeForDecl);
1908  return QualType(Decl->TypeForDecl, 0);
1909}
1910
1911/// \brief Retrieve a substitution-result type.
1912QualType
1913ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
1914                                         QualType Replacement) {
1915  assert(Replacement.isCanonical()
1916         && "replacement types must always be canonical");
1917
1918  llvm::FoldingSetNodeID ID;
1919  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
1920  void *InsertPos = 0;
1921  SubstTemplateTypeParmType *SubstParm
1922    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1923
1924  if (!SubstParm) {
1925    SubstParm = new (*this, TypeAlignment)
1926      SubstTemplateTypeParmType(Parm, Replacement);
1927    Types.push_back(SubstParm);
1928    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
1929  }
1930
1931  return QualType(SubstParm, 0);
1932}
1933
1934/// \brief Retrieve the template type parameter type for a template
1935/// parameter or parameter pack with the given depth, index, and (optionally)
1936/// name.
1937QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
1938                                             bool ParameterPack,
1939                                             IdentifierInfo *Name) {
1940  llvm::FoldingSetNodeID ID;
1941  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, Name);
1942  void *InsertPos = 0;
1943  TemplateTypeParmType *TypeParm
1944    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1945
1946  if (TypeParm)
1947    return QualType(TypeParm, 0);
1948
1949  if (Name) {
1950    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
1951    TypeParm = new (*this, TypeAlignment)
1952      TemplateTypeParmType(Depth, Index, ParameterPack, Name, Canon);
1953
1954    TemplateTypeParmType *TypeCheck
1955      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
1956    assert(!TypeCheck && "Template type parameter canonical type broken");
1957    (void)TypeCheck;
1958  } else
1959    TypeParm = new (*this, TypeAlignment)
1960      TemplateTypeParmType(Depth, Index, ParameterPack);
1961
1962  Types.push_back(TypeParm);
1963  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
1964
1965  return QualType(TypeParm, 0);
1966}
1967
1968TypeSourceInfo *
1969ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
1970                                              SourceLocation NameLoc,
1971                                        const TemplateArgumentListInfo &Args,
1972                                              QualType CanonType) {
1973  QualType TST = getTemplateSpecializationType(Name, Args, CanonType);
1974
1975  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
1976  TemplateSpecializationTypeLoc TL
1977    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
1978  TL.setTemplateNameLoc(NameLoc);
1979  TL.setLAngleLoc(Args.getLAngleLoc());
1980  TL.setRAngleLoc(Args.getRAngleLoc());
1981  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
1982    TL.setArgLocInfo(i, Args[i].getLocInfo());
1983  return DI;
1984}
1985
1986QualType
1987ASTContext::getTemplateSpecializationType(TemplateName Template,
1988                                          const TemplateArgumentListInfo &Args,
1989                                          QualType Canon) {
1990  unsigned NumArgs = Args.size();
1991
1992  llvm::SmallVector<TemplateArgument, 4> ArgVec;
1993  ArgVec.reserve(NumArgs);
1994  for (unsigned i = 0; i != NumArgs; ++i)
1995    ArgVec.push_back(Args[i].getArgument());
1996
1997  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
1998                                       Canon);
1999}
2000
2001QualType
2002ASTContext::getTemplateSpecializationType(TemplateName Template,
2003                                          const TemplateArgument *Args,
2004                                          unsigned NumArgs,
2005                                          QualType Canon) {
2006  if (!Canon.isNull())
2007    Canon = getCanonicalType(Canon);
2008  else
2009    Canon = getCanonicalTemplateSpecializationType(Template, Args, NumArgs);
2010
2011  // Allocate the (non-canonical) template specialization type, but don't
2012  // try to unique it: these types typically have location information that
2013  // we don't unique and don't want to lose.
2014  void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2015                        sizeof(TemplateArgument) * NumArgs),
2016                       TypeAlignment);
2017  TemplateSpecializationType *Spec
2018    = new (Mem) TemplateSpecializationType(Template,
2019                                           Args, NumArgs,
2020                                           Canon);
2021
2022  Types.push_back(Spec);
2023  return QualType(Spec, 0);
2024}
2025
2026QualType
2027ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
2028                                                   const TemplateArgument *Args,
2029                                                   unsigned NumArgs) {
2030  // Build the canonical template specialization type.
2031  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
2032  llvm::SmallVector<TemplateArgument, 4> CanonArgs;
2033  CanonArgs.reserve(NumArgs);
2034  for (unsigned I = 0; I != NumArgs; ++I)
2035    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
2036
2037  // Determine whether this canonical template specialization type already
2038  // exists.
2039  llvm::FoldingSetNodeID ID;
2040  TemplateSpecializationType::Profile(ID, CanonTemplate,
2041                                      CanonArgs.data(), NumArgs, *this);
2042
2043  void *InsertPos = 0;
2044  TemplateSpecializationType *Spec
2045    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2046
2047  if (!Spec) {
2048    // Allocate a new canonical template specialization type.
2049    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2050                          sizeof(TemplateArgument) * NumArgs),
2051                         TypeAlignment);
2052    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
2053                                                CanonArgs.data(), NumArgs,
2054                                                QualType());
2055    Types.push_back(Spec);
2056    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
2057  }
2058
2059  assert(Spec->isDependentType() &&
2060         "Non-dependent template-id type must have a canonical type");
2061  return QualType(Spec, 0);
2062}
2063
2064QualType
2065ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
2066                              NestedNameSpecifier *NNS,
2067                              QualType NamedType) {
2068  llvm::FoldingSetNodeID ID;
2069  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2070
2071  void *InsertPos = 0;
2072  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2073  if (T)
2074    return QualType(T, 0);
2075
2076  QualType Canon = NamedType;
2077  if (!Canon.isCanonical()) {
2078    Canon = getCanonicalType(NamedType);
2079    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2080    assert(!CheckT && "Elaborated canonical type broken");
2081    (void)CheckT;
2082  }
2083
2084  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2085  Types.push_back(T);
2086  ElaboratedTypes.InsertNode(T, InsertPos);
2087  return QualType(T, 0);
2088}
2089
2090QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2091                                          NestedNameSpecifier *NNS,
2092                                          const IdentifierInfo *Name,
2093                                          QualType Canon) {
2094  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2095
2096  if (Canon.isNull()) {
2097    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2098    ElaboratedTypeKeyword CanonKeyword = Keyword;
2099    if (Keyword == ETK_None)
2100      CanonKeyword = ETK_Typename;
2101
2102    if (CanonNNS != NNS || CanonKeyword != Keyword)
2103      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2104  }
2105
2106  llvm::FoldingSetNodeID ID;
2107  DependentNameType::Profile(ID, Keyword, NNS, Name);
2108
2109  void *InsertPos = 0;
2110  DependentNameType *T
2111    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2112  if (T)
2113    return QualType(T, 0);
2114
2115  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
2116  Types.push_back(T);
2117  DependentNameTypes.InsertNode(T, InsertPos);
2118  return QualType(T, 0);
2119}
2120
2121QualType
2122ASTContext::getDependentTemplateSpecializationType(
2123                                 ElaboratedTypeKeyword Keyword,
2124                                 NestedNameSpecifier *NNS,
2125                                 const IdentifierInfo *Name,
2126                                 const TemplateArgumentListInfo &Args) {
2127  // TODO: avoid this copy
2128  llvm::SmallVector<TemplateArgument, 16> ArgCopy;
2129  for (unsigned I = 0, E = Args.size(); I != E; ++I)
2130    ArgCopy.push_back(Args[I].getArgument());
2131  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
2132                                                ArgCopy.size(),
2133                                                ArgCopy.data());
2134}
2135
2136QualType
2137ASTContext::getDependentTemplateSpecializationType(
2138                                 ElaboratedTypeKeyword Keyword,
2139                                 NestedNameSpecifier *NNS,
2140                                 const IdentifierInfo *Name,
2141                                 unsigned NumArgs,
2142                                 const TemplateArgument *Args) {
2143  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2144
2145  llvm::FoldingSetNodeID ID;
2146  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
2147                                               Name, NumArgs, Args);
2148
2149  void *InsertPos = 0;
2150  DependentTemplateSpecializationType *T
2151    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2152  if (T)
2153    return QualType(T, 0);
2154
2155  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2156
2157  ElaboratedTypeKeyword CanonKeyword = Keyword;
2158  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
2159
2160  bool AnyNonCanonArgs = false;
2161  llvm::SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
2162  for (unsigned I = 0; I != NumArgs; ++I) {
2163    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
2164    if (!CanonArgs[I].structurallyEquals(Args[I]))
2165      AnyNonCanonArgs = true;
2166  }
2167
2168  QualType Canon;
2169  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
2170    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
2171                                                   Name, NumArgs,
2172                                                   CanonArgs.data());
2173
2174    // Find the insert position again.
2175    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2176  }
2177
2178  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
2179                        sizeof(TemplateArgument) * NumArgs),
2180                       TypeAlignment);
2181  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
2182                                                    Name, NumArgs, Args, Canon);
2183  Types.push_back(T);
2184  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
2185  return QualType(T, 0);
2186}
2187
2188/// CmpProtocolNames - Comparison predicate for sorting protocols
2189/// alphabetically.
2190static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
2191                            const ObjCProtocolDecl *RHS) {
2192  return LHS->getDeclName() < RHS->getDeclName();
2193}
2194
2195static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
2196                                unsigned NumProtocols) {
2197  if (NumProtocols == 0) return true;
2198
2199  for (unsigned i = 1; i != NumProtocols; ++i)
2200    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]))
2201      return false;
2202  return true;
2203}
2204
2205static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
2206                                   unsigned &NumProtocols) {
2207  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
2208
2209  // Sort protocols, keyed by name.
2210  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
2211
2212  // Remove duplicates.
2213  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
2214  NumProtocols = ProtocolsEnd-Protocols;
2215}
2216
2217QualType ASTContext::getObjCObjectType(QualType BaseType,
2218                                       ObjCProtocolDecl * const *Protocols,
2219                                       unsigned NumProtocols) {
2220  // If the base type is an interface and there aren't any protocols
2221  // to add, then the interface type will do just fine.
2222  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
2223    return BaseType;
2224
2225  // Look in the folding set for an existing type.
2226  llvm::FoldingSetNodeID ID;
2227  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
2228  void *InsertPos = 0;
2229  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
2230    return QualType(QT, 0);
2231
2232  // Build the canonical type, which has the canonical base type and
2233  // a sorted-and-uniqued list of protocols.
2234  QualType Canonical;
2235  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
2236  if (!ProtocolsSorted || !BaseType.isCanonical()) {
2237    if (!ProtocolsSorted) {
2238      llvm::SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
2239                                                     Protocols + NumProtocols);
2240      unsigned UniqueCount = NumProtocols;
2241
2242      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
2243      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2244                                    &Sorted[0], UniqueCount);
2245    } else {
2246      Canonical = getObjCObjectType(getCanonicalType(BaseType),
2247                                    Protocols, NumProtocols);
2248    }
2249
2250    // Regenerate InsertPos.
2251    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
2252  }
2253
2254  unsigned Size = sizeof(ObjCObjectTypeImpl);
2255  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
2256  void *Mem = Allocate(Size, TypeAlignment);
2257  ObjCObjectTypeImpl *T =
2258    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
2259
2260  Types.push_back(T);
2261  ObjCObjectTypes.InsertNode(T, InsertPos);
2262  return QualType(T, 0);
2263}
2264
2265/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
2266/// the given object type.
2267QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) {
2268  llvm::FoldingSetNodeID ID;
2269  ObjCObjectPointerType::Profile(ID, ObjectT);
2270
2271  void *InsertPos = 0;
2272  if (ObjCObjectPointerType *QT =
2273              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2274    return QualType(QT, 0);
2275
2276  // Find the canonical object type.
2277  QualType Canonical;
2278  if (!ObjectT.isCanonical()) {
2279    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
2280
2281    // Regenerate InsertPos.
2282    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2283  }
2284
2285  // No match.
2286  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
2287  ObjCObjectPointerType *QType =
2288    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
2289
2290  Types.push_back(QType);
2291  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
2292  return QualType(QType, 0);
2293}
2294
2295/// getObjCInterfaceType - Return the unique reference to the type for the
2296/// specified ObjC interface decl. The list of protocols is optional.
2297QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl) {
2298  if (Decl->TypeForDecl)
2299    return QualType(Decl->TypeForDecl, 0);
2300
2301  // FIXME: redeclarations?
2302  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
2303  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
2304  Decl->TypeForDecl = T;
2305  Types.push_back(T);
2306  return QualType(T, 0);
2307}
2308
2309/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
2310/// TypeOfExprType AST's (since expression's are never shared). For example,
2311/// multiple declarations that refer to "typeof(x)" all contain different
2312/// DeclRefExpr's. This doesn't effect the type checker, since it operates
2313/// on canonical type's (which are always unique).
2314QualType ASTContext::getTypeOfExprType(Expr *tofExpr) {
2315  TypeOfExprType *toe;
2316  if (tofExpr->isTypeDependent()) {
2317    llvm::FoldingSetNodeID ID;
2318    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
2319
2320    void *InsertPos = 0;
2321    DependentTypeOfExprType *Canon
2322      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
2323    if (Canon) {
2324      // We already have a "canonical" version of an identical, dependent
2325      // typeof(expr) type. Use that as our canonical type.
2326      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
2327                                          QualType((TypeOfExprType*)Canon, 0));
2328    }
2329    else {
2330      // Build a new, canonical typeof(expr) type.
2331      Canon
2332        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
2333      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
2334      toe = Canon;
2335    }
2336  } else {
2337    QualType Canonical = getCanonicalType(tofExpr->getType());
2338    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
2339  }
2340  Types.push_back(toe);
2341  return QualType(toe, 0);
2342}
2343
2344/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
2345/// TypeOfType AST's. The only motivation to unique these nodes would be
2346/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
2347/// an issue. This doesn't effect the type checker, since it operates
2348/// on canonical type's (which are always unique).
2349QualType ASTContext::getTypeOfType(QualType tofType) {
2350  QualType Canonical = getCanonicalType(tofType);
2351  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
2352  Types.push_back(tot);
2353  return QualType(tot, 0);
2354}
2355
2356/// getDecltypeForExpr - Given an expr, will return the decltype for that
2357/// expression, according to the rules in C++0x [dcl.type.simple]p4
2358static QualType getDecltypeForExpr(const Expr *e, ASTContext &Context) {
2359  if (e->isTypeDependent())
2360    return Context.DependentTy;
2361
2362  // If e is an id expression or a class member access, decltype(e) is defined
2363  // as the type of the entity named by e.
2364  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(e)) {
2365    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
2366      return VD->getType();
2367  }
2368  if (const MemberExpr *ME = dyn_cast<MemberExpr>(e)) {
2369    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2370      return FD->getType();
2371  }
2372  // If e is a function call or an invocation of an overloaded operator,
2373  // (parentheses around e are ignored), decltype(e) is defined as the
2374  // return type of that function.
2375  if (const CallExpr *CE = dyn_cast<CallExpr>(e->IgnoreParens()))
2376    return CE->getCallReturnType();
2377
2378  QualType T = e->getType();
2379
2380  // Otherwise, where T is the type of e, if e is an lvalue, decltype(e) is
2381  // defined as T&, otherwise decltype(e) is defined as T.
2382  if (e->isLvalue(Context) == Expr::LV_Valid)
2383    T = Context.getLValueReferenceType(T);
2384
2385  return T;
2386}
2387
2388/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
2389/// DecltypeType AST's. The only motivation to unique these nodes would be
2390/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
2391/// an issue. This doesn't effect the type checker, since it operates
2392/// on canonical type's (which are always unique).
2393QualType ASTContext::getDecltypeType(Expr *e) {
2394  DecltypeType *dt;
2395  if (e->isTypeDependent()) {
2396    llvm::FoldingSetNodeID ID;
2397    DependentDecltypeType::Profile(ID, *this, e);
2398
2399    void *InsertPos = 0;
2400    DependentDecltypeType *Canon
2401      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
2402    if (Canon) {
2403      // We already have a "canonical" version of an equivalent, dependent
2404      // decltype type. Use that as our canonical type.
2405      dt = new (*this, TypeAlignment) DecltypeType(e, DependentTy,
2406                                       QualType((DecltypeType*)Canon, 0));
2407    }
2408    else {
2409      // Build a new, canonical typeof(expr) type.
2410      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
2411      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
2412      dt = Canon;
2413    }
2414  } else {
2415    QualType T = getDecltypeForExpr(e, *this);
2416    dt = new (*this, TypeAlignment) DecltypeType(e, T, getCanonicalType(T));
2417  }
2418  Types.push_back(dt);
2419  return QualType(dt, 0);
2420}
2421
2422/// getTagDeclType - Return the unique reference to the type for the
2423/// specified TagDecl (struct/union/class/enum) decl.
2424QualType ASTContext::getTagDeclType(const TagDecl *Decl) {
2425  assert (Decl);
2426  // FIXME: What is the design on getTagDeclType when it requires casting
2427  // away const?  mutable?
2428  return getTypeDeclType(const_cast<TagDecl*>(Decl));
2429}
2430
2431/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
2432/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
2433/// needs to agree with the definition in <stddef.h>.
2434CanQualType ASTContext::getSizeType() const {
2435  return getFromTargetType(Target.getSizeType());
2436}
2437
2438/// getSignedWCharType - Return the type of "signed wchar_t".
2439/// Used when in C++, as a GCC extension.
2440QualType ASTContext::getSignedWCharType() const {
2441  // FIXME: derive from "Target" ?
2442  return WCharTy;
2443}
2444
2445/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
2446/// Used when in C++, as a GCC extension.
2447QualType ASTContext::getUnsignedWCharType() const {
2448  // FIXME: derive from "Target" ?
2449  return UnsignedIntTy;
2450}
2451
2452/// getPointerDiffType - Return the unique type for "ptrdiff_t" (ref?)
2453/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
2454QualType ASTContext::getPointerDiffType() const {
2455  return getFromTargetType(Target.getPtrDiffType(0));
2456}
2457
2458//===----------------------------------------------------------------------===//
2459//                              Type Operators
2460//===----------------------------------------------------------------------===//
2461
2462CanQualType ASTContext::getCanonicalParamType(QualType T) {
2463  // Push qualifiers into arrays, and then discard any remaining
2464  // qualifiers.
2465  T = getCanonicalType(T);
2466  T = getVariableArrayDecayedType(T);
2467  const Type *Ty = T.getTypePtr();
2468  QualType Result;
2469  if (isa<ArrayType>(Ty)) {
2470    Result = getArrayDecayedType(QualType(Ty,0));
2471  } else if (isa<FunctionType>(Ty)) {
2472    Result = getPointerType(QualType(Ty, 0));
2473  } else {
2474    Result = QualType(Ty, 0);
2475  }
2476
2477  return CanQualType::CreateUnsafe(Result);
2478}
2479
2480/// getCanonicalType - Return the canonical (structural) type corresponding to
2481/// the specified potentially non-canonical type.  The non-canonical version
2482/// of a type may have many "decorated" versions of types.  Decorators can
2483/// include typedefs, 'typeof' operators, etc. The returned type is guaranteed
2484/// to be free of any of these, allowing two canonical types to be compared
2485/// for exact equality with a simple pointer comparison.
2486CanQualType ASTContext::getCanonicalType(QualType T) {
2487  QualifierCollector Quals;
2488  const Type *Ptr = Quals.strip(T);
2489  QualType CanType = Ptr->getCanonicalTypeInternal();
2490
2491  // The canonical internal type will be the canonical type *except*
2492  // that we push type qualifiers down through array types.
2493
2494  // If there are no new qualifiers to push down, stop here.
2495  if (!Quals.hasQualifiers())
2496    return CanQualType::CreateUnsafe(CanType);
2497
2498  // If the type qualifiers are on an array type, get the canonical
2499  // type of the array with the qualifiers applied to the element
2500  // type.
2501  ArrayType *AT = dyn_cast<ArrayType>(CanType);
2502  if (!AT)
2503    return CanQualType::CreateUnsafe(getQualifiedType(CanType, Quals));
2504
2505  // Get the canonical version of the element with the extra qualifiers on it.
2506  // This can recursively sink qualifiers through multiple levels of arrays.
2507  QualType NewEltTy = getQualifiedType(AT->getElementType(), Quals);
2508  NewEltTy = getCanonicalType(NewEltTy);
2509
2510  if (ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
2511    return CanQualType::CreateUnsafe(
2512             getConstantArrayType(NewEltTy, CAT->getSize(),
2513                                  CAT->getSizeModifier(),
2514                                  CAT->getIndexTypeCVRQualifiers()));
2515  if (IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT))
2516    return CanQualType::CreateUnsafe(
2517             getIncompleteArrayType(NewEltTy, IAT->getSizeModifier(),
2518                                    IAT->getIndexTypeCVRQualifiers()));
2519
2520  if (DependentSizedArrayType *DSAT = dyn_cast<DependentSizedArrayType>(AT))
2521    return CanQualType::CreateUnsafe(
2522             getDependentSizedArrayType(NewEltTy,
2523                                        DSAT->getSizeExpr() ?
2524                                          DSAT->getSizeExpr()->Retain() : 0,
2525                                        DSAT->getSizeModifier(),
2526                                        DSAT->getIndexTypeCVRQualifiers(),
2527                        DSAT->getBracketsRange())->getCanonicalTypeInternal());
2528
2529  VariableArrayType *VAT = cast<VariableArrayType>(AT);
2530  return CanQualType::CreateUnsafe(getVariableArrayType(NewEltTy,
2531                                                        VAT->getSizeExpr() ?
2532                                              VAT->getSizeExpr()->Retain() : 0,
2533                                                        VAT->getSizeModifier(),
2534                                              VAT->getIndexTypeCVRQualifiers(),
2535                                                     VAT->getBracketsRange()));
2536}
2537
2538QualType ASTContext::getUnqualifiedArrayType(QualType T,
2539                                             Qualifiers &Quals) {
2540  Quals = T.getQualifiers();
2541  const ArrayType *AT = getAsArrayType(T);
2542  if (!AT) {
2543    return T.getUnqualifiedType();
2544  }
2545
2546  QualType Elt = AT->getElementType();
2547  QualType UnqualElt = getUnqualifiedArrayType(Elt, Quals);
2548  if (Elt == UnqualElt)
2549    return T;
2550
2551  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
2552    return getConstantArrayType(UnqualElt, CAT->getSize(),
2553                                CAT->getSizeModifier(), 0);
2554  }
2555
2556  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
2557    return getIncompleteArrayType(UnqualElt, IAT->getSizeModifier(), 0);
2558  }
2559
2560  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
2561    return getVariableArrayType(UnqualElt,
2562                                VAT->getSizeExpr() ?
2563                                VAT->getSizeExpr()->Retain() : 0,
2564                                VAT->getSizeModifier(),
2565                                VAT->getIndexTypeCVRQualifiers(),
2566                                VAT->getBracketsRange());
2567  }
2568
2569  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
2570  return getDependentSizedArrayType(UnqualElt, DSAT->getSizeExpr()->Retain(),
2571                                    DSAT->getSizeModifier(), 0,
2572                                    SourceRange());
2573}
2574
2575/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
2576/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
2577/// they point to and return true. If T1 and T2 aren't pointer types
2578/// or pointer-to-member types, or if they are not similar at this
2579/// level, returns false and leaves T1 and T2 unchanged. Top-level
2580/// qualifiers on T1 and T2 are ignored. This function will typically
2581/// be called in a loop that successively "unwraps" pointer and
2582/// pointer-to-member types to compare them at each level.
2583bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
2584  const PointerType *T1PtrType = T1->getAs<PointerType>(),
2585                    *T2PtrType = T2->getAs<PointerType>();
2586  if (T1PtrType && T2PtrType) {
2587    T1 = T1PtrType->getPointeeType();
2588    T2 = T2PtrType->getPointeeType();
2589    return true;
2590  }
2591
2592  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
2593                          *T2MPType = T2->getAs<MemberPointerType>();
2594  if (T1MPType && T2MPType &&
2595      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
2596                             QualType(T2MPType->getClass(), 0))) {
2597    T1 = T1MPType->getPointeeType();
2598    T2 = T2MPType->getPointeeType();
2599    return true;
2600  }
2601
2602  if (getLangOptions().ObjC1) {
2603    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
2604                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
2605    if (T1OPType && T2OPType) {
2606      T1 = T1OPType->getPointeeType();
2607      T2 = T2OPType->getPointeeType();
2608      return true;
2609    }
2610  }
2611
2612  // FIXME: Block pointers, too?
2613
2614  return false;
2615}
2616
2617DeclarationNameInfo ASTContext::getNameForTemplate(TemplateName Name,
2618                                                   SourceLocation NameLoc) {
2619  if (TemplateDecl *TD = Name.getAsTemplateDecl())
2620    // DNInfo work in progress: CHECKME: what about DNLoc?
2621    return DeclarationNameInfo(TD->getDeclName(), NameLoc);
2622
2623  if (DependentTemplateName *DTN = Name.getAsDependentTemplateName()) {
2624    DeclarationName DName;
2625    if (DTN->isIdentifier()) {
2626      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
2627      return DeclarationNameInfo(DName, NameLoc);
2628    } else {
2629      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
2630      // DNInfo work in progress: FIXME: source locations?
2631      DeclarationNameLoc DNLoc;
2632      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
2633      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
2634      return DeclarationNameInfo(DName, NameLoc, DNLoc);
2635    }
2636  }
2637
2638  OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
2639  assert(Storage);
2640  // DNInfo work in progress: CHECKME: what about DNLoc?
2641  return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
2642}
2643
2644TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) {
2645  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
2646    if (TemplateTemplateParmDecl *TTP
2647                              = dyn_cast<TemplateTemplateParmDecl>(Template))
2648      Template = getCanonicalTemplateTemplateParmDecl(TTP);
2649
2650    // The canonical template name is the canonical template declaration.
2651    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
2652  }
2653
2654  assert(!Name.getAsOverloadedTemplate());
2655
2656  DependentTemplateName *DTN = Name.getAsDependentTemplateName();
2657  assert(DTN && "Non-dependent template names must refer to template decls.");
2658  return DTN->CanonicalTemplateName;
2659}
2660
2661bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
2662  X = getCanonicalTemplateName(X);
2663  Y = getCanonicalTemplateName(Y);
2664  return X.getAsVoidPointer() == Y.getAsVoidPointer();
2665}
2666
2667TemplateArgument
2668ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) {
2669  switch (Arg.getKind()) {
2670    case TemplateArgument::Null:
2671      return Arg;
2672
2673    case TemplateArgument::Expression:
2674      return Arg;
2675
2676    case TemplateArgument::Declaration:
2677      return TemplateArgument(Arg.getAsDecl()->getCanonicalDecl());
2678
2679    case TemplateArgument::Template:
2680      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
2681
2682    case TemplateArgument::Integral:
2683      return TemplateArgument(*Arg.getAsIntegral(),
2684                              getCanonicalType(Arg.getIntegralType()));
2685
2686    case TemplateArgument::Type:
2687      return TemplateArgument(getCanonicalType(Arg.getAsType()));
2688
2689    case TemplateArgument::Pack: {
2690      // FIXME: Allocate in ASTContext
2691      TemplateArgument *CanonArgs = new TemplateArgument[Arg.pack_size()];
2692      unsigned Idx = 0;
2693      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
2694                                        AEnd = Arg.pack_end();
2695           A != AEnd; (void)++A, ++Idx)
2696        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
2697
2698      TemplateArgument Result;
2699      Result.setArgumentPack(CanonArgs, Arg.pack_size(), false);
2700      return Result;
2701    }
2702  }
2703
2704  // Silence GCC warning
2705  assert(false && "Unhandled template argument kind");
2706  return TemplateArgument();
2707}
2708
2709NestedNameSpecifier *
2710ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) {
2711  if (!NNS)
2712    return 0;
2713
2714  switch (NNS->getKind()) {
2715  case NestedNameSpecifier::Identifier:
2716    // Canonicalize the prefix but keep the identifier the same.
2717    return NestedNameSpecifier::Create(*this,
2718                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
2719                                       NNS->getAsIdentifier());
2720
2721  case NestedNameSpecifier::Namespace:
2722    // A namespace is canonical; build a nested-name-specifier with
2723    // this namespace and no prefix.
2724    return NestedNameSpecifier::Create(*this, 0, NNS->getAsNamespace());
2725
2726  case NestedNameSpecifier::TypeSpec:
2727  case NestedNameSpecifier::TypeSpecWithTemplate: {
2728    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
2729    return NestedNameSpecifier::Create(*this, 0,
2730                 NNS->getKind() == NestedNameSpecifier::TypeSpecWithTemplate,
2731                                       T.getTypePtr());
2732  }
2733
2734  case NestedNameSpecifier::Global:
2735    // The global specifier is canonical and unique.
2736    return NNS;
2737  }
2738
2739  // Required to silence a GCC warning
2740  return 0;
2741}
2742
2743
2744const ArrayType *ASTContext::getAsArrayType(QualType T) {
2745  // Handle the non-qualified case efficiently.
2746  if (!T.hasLocalQualifiers()) {
2747    // Handle the common positive case fast.
2748    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
2749      return AT;
2750  }
2751
2752  // Handle the common negative case fast.
2753  QualType CType = T->getCanonicalTypeInternal();
2754  if (!isa<ArrayType>(CType))
2755    return 0;
2756
2757  // Apply any qualifiers from the array type to the element type.  This
2758  // implements C99 6.7.3p8: "If the specification of an array type includes
2759  // any type qualifiers, the element type is so qualified, not the array type."
2760
2761  // If we get here, we either have type qualifiers on the type, or we have
2762  // sugar such as a typedef in the way.  If we have type qualifiers on the type
2763  // we must propagate them down into the element type.
2764
2765  QualifierCollector Qs;
2766  const Type *Ty = Qs.strip(T.getDesugaredType());
2767
2768  // If we have a simple case, just return now.
2769  const ArrayType *ATy = dyn_cast<ArrayType>(Ty);
2770  if (ATy == 0 || Qs.empty())
2771    return ATy;
2772
2773  // Otherwise, we have an array and we have qualifiers on it.  Push the
2774  // qualifiers into the array element type and return a new array type.
2775  // Get the canonical version of the element with the extra qualifiers on it.
2776  // This can recursively sink qualifiers through multiple levels of arrays.
2777  QualType NewEltTy = getQualifiedType(ATy->getElementType(), Qs);
2778
2779  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
2780    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
2781                                                CAT->getSizeModifier(),
2782                                           CAT->getIndexTypeCVRQualifiers()));
2783  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
2784    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
2785                                                  IAT->getSizeModifier(),
2786                                           IAT->getIndexTypeCVRQualifiers()));
2787
2788  if (const DependentSizedArrayType *DSAT
2789        = dyn_cast<DependentSizedArrayType>(ATy))
2790    return cast<ArrayType>(
2791                     getDependentSizedArrayType(NewEltTy,
2792                                                DSAT->getSizeExpr() ?
2793                                              DSAT->getSizeExpr()->Retain() : 0,
2794                                                DSAT->getSizeModifier(),
2795                                              DSAT->getIndexTypeCVRQualifiers(),
2796                                                DSAT->getBracketsRange()));
2797
2798  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
2799  return cast<ArrayType>(getVariableArrayType(NewEltTy,
2800                                              VAT->getSizeExpr() ?
2801                                              VAT->getSizeExpr()->Retain() : 0,
2802                                              VAT->getSizeModifier(),
2803                                              VAT->getIndexTypeCVRQualifiers(),
2804                                              VAT->getBracketsRange()));
2805}
2806
2807/// getArrayDecayedType - Return the properly qualified result of decaying the
2808/// specified array type to a pointer.  This operation is non-trivial when
2809/// handling typedefs etc.  The canonical type of "T" must be an array type,
2810/// this returns a pointer to a properly qualified element of the array.
2811///
2812/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
2813QualType ASTContext::getArrayDecayedType(QualType Ty) {
2814  // Get the element type with 'getAsArrayType' so that we don't lose any
2815  // typedefs in the element type of the array.  This also handles propagation
2816  // of type qualifiers from the array type into the element type if present
2817  // (C99 6.7.3p8).
2818  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
2819  assert(PrettyArrayType && "Not an array type!");
2820
2821  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
2822
2823  // int x[restrict 4] ->  int *restrict
2824  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
2825}
2826
2827QualType ASTContext::getBaseElementType(QualType QT) {
2828  QualifierCollector Qs;
2829  while (const ArrayType *AT = getAsArrayType(QualType(Qs.strip(QT), 0)))
2830    QT = AT->getElementType();
2831  return Qs.apply(QT);
2832}
2833
2834QualType ASTContext::getBaseElementType(const ArrayType *AT) {
2835  QualType ElemTy = AT->getElementType();
2836
2837  if (const ArrayType *AT = getAsArrayType(ElemTy))
2838    return getBaseElementType(AT);
2839
2840  return ElemTy;
2841}
2842
2843/// getConstantArrayElementCount - Returns number of constant array elements.
2844uint64_t
2845ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
2846  uint64_t ElementCount = 1;
2847  do {
2848    ElementCount *= CA->getSize().getZExtValue();
2849    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
2850  } while (CA);
2851  return ElementCount;
2852}
2853
2854/// getFloatingRank - Return a relative rank for floating point types.
2855/// This routine will assert if passed a built-in type that isn't a float.
2856static FloatingRank getFloatingRank(QualType T) {
2857  if (const ComplexType *CT = T->getAs<ComplexType>())
2858    return getFloatingRank(CT->getElementType());
2859
2860  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
2861  switch (T->getAs<BuiltinType>()->getKind()) {
2862  default: assert(0 && "getFloatingRank(): not a floating type");
2863  case BuiltinType::Float:      return FloatRank;
2864  case BuiltinType::Double:     return DoubleRank;
2865  case BuiltinType::LongDouble: return LongDoubleRank;
2866  }
2867}
2868
2869/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
2870/// point or a complex type (based on typeDomain/typeSize).
2871/// 'typeDomain' is a real floating point or complex type.
2872/// 'typeSize' is a real floating point or complex type.
2873QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
2874                                                       QualType Domain) const {
2875  FloatingRank EltRank = getFloatingRank(Size);
2876  if (Domain->isComplexType()) {
2877    switch (EltRank) {
2878    default: assert(0 && "getFloatingRank(): illegal value for rank");
2879    case FloatRank:      return FloatComplexTy;
2880    case DoubleRank:     return DoubleComplexTy;
2881    case LongDoubleRank: return LongDoubleComplexTy;
2882    }
2883  }
2884
2885  assert(Domain->isRealFloatingType() && "Unknown domain!");
2886  switch (EltRank) {
2887  default: assert(0 && "getFloatingRank(): illegal value for rank");
2888  case FloatRank:      return FloatTy;
2889  case DoubleRank:     return DoubleTy;
2890  case LongDoubleRank: return LongDoubleTy;
2891  }
2892}
2893
2894/// getFloatingTypeOrder - Compare the rank of the two specified floating
2895/// point types, ignoring the domain of the type (i.e. 'double' ==
2896/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
2897/// LHS < RHS, return -1.
2898int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) {
2899  FloatingRank LHSR = getFloatingRank(LHS);
2900  FloatingRank RHSR = getFloatingRank(RHS);
2901
2902  if (LHSR == RHSR)
2903    return 0;
2904  if (LHSR > RHSR)
2905    return 1;
2906  return -1;
2907}
2908
2909/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
2910/// routine will assert if passed a built-in type that isn't an integer or enum,
2911/// or if it is not canonicalized.
2912unsigned ASTContext::getIntegerRank(Type *T) {
2913  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
2914  if (EnumType* ET = dyn_cast<EnumType>(T))
2915    T = ET->getDecl()->getPromotionType().getTypePtr();
2916
2917  if (T->isSpecificBuiltinType(BuiltinType::WChar))
2918    T = getFromTargetType(Target.getWCharType()).getTypePtr();
2919
2920  if (T->isSpecificBuiltinType(BuiltinType::Char16))
2921    T = getFromTargetType(Target.getChar16Type()).getTypePtr();
2922
2923  if (T->isSpecificBuiltinType(BuiltinType::Char32))
2924    T = getFromTargetType(Target.getChar32Type()).getTypePtr();
2925
2926  switch (cast<BuiltinType>(T)->getKind()) {
2927  default: assert(0 && "getIntegerRank(): not a built-in integer");
2928  case BuiltinType::Bool:
2929    return 1 + (getIntWidth(BoolTy) << 3);
2930  case BuiltinType::Char_S:
2931  case BuiltinType::Char_U:
2932  case BuiltinType::SChar:
2933  case BuiltinType::UChar:
2934    return 2 + (getIntWidth(CharTy) << 3);
2935  case BuiltinType::Short:
2936  case BuiltinType::UShort:
2937    return 3 + (getIntWidth(ShortTy) << 3);
2938  case BuiltinType::Int:
2939  case BuiltinType::UInt:
2940    return 4 + (getIntWidth(IntTy) << 3);
2941  case BuiltinType::Long:
2942  case BuiltinType::ULong:
2943    return 5 + (getIntWidth(LongTy) << 3);
2944  case BuiltinType::LongLong:
2945  case BuiltinType::ULongLong:
2946    return 6 + (getIntWidth(LongLongTy) << 3);
2947  case BuiltinType::Int128:
2948  case BuiltinType::UInt128:
2949    return 7 + (getIntWidth(Int128Ty) << 3);
2950  }
2951}
2952
2953/// \brief Whether this is a promotable bitfield reference according
2954/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
2955///
2956/// \returns the type this bit-field will promote to, or NULL if no
2957/// promotion occurs.
2958QualType ASTContext::isPromotableBitField(Expr *E) {
2959  if (E->isTypeDependent() || E->isValueDependent())
2960    return QualType();
2961
2962  FieldDecl *Field = E->getBitField();
2963  if (!Field)
2964    return QualType();
2965
2966  QualType FT = Field->getType();
2967
2968  llvm::APSInt BitWidthAP = Field->getBitWidth()->EvaluateAsInt(*this);
2969  uint64_t BitWidth = BitWidthAP.getZExtValue();
2970  uint64_t IntSize = getTypeSize(IntTy);
2971  // GCC extension compatibility: if the bit-field size is less than or equal
2972  // to the size of int, it gets promoted no matter what its type is.
2973  // For instance, unsigned long bf : 4 gets promoted to signed int.
2974  if (BitWidth < IntSize)
2975    return IntTy;
2976
2977  if (BitWidth == IntSize)
2978    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
2979
2980  // Types bigger than int are not subject to promotions, and therefore act
2981  // like the base type.
2982  // FIXME: This doesn't quite match what gcc does, but what gcc does here
2983  // is ridiculous.
2984  return QualType();
2985}
2986
2987/// getPromotedIntegerType - Returns the type that Promotable will
2988/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
2989/// integer type.
2990QualType ASTContext::getPromotedIntegerType(QualType Promotable) {
2991  assert(!Promotable.isNull());
2992  assert(Promotable->isPromotableIntegerType());
2993  if (const EnumType *ET = Promotable->getAs<EnumType>())
2994    return ET->getDecl()->getPromotionType();
2995  if (Promotable->isSignedIntegerType())
2996    return IntTy;
2997  uint64_t PromotableSize = getTypeSize(Promotable);
2998  uint64_t IntSize = getTypeSize(IntTy);
2999  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
3000  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
3001}
3002
3003/// getIntegerTypeOrder - Returns the highest ranked integer type:
3004/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3005/// LHS < RHS, return -1.
3006int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) {
3007  Type *LHSC = getCanonicalType(LHS).getTypePtr();
3008  Type *RHSC = getCanonicalType(RHS).getTypePtr();
3009  if (LHSC == RHSC) return 0;
3010
3011  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
3012  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
3013
3014  unsigned LHSRank = getIntegerRank(LHSC);
3015  unsigned RHSRank = getIntegerRank(RHSC);
3016
3017  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
3018    if (LHSRank == RHSRank) return 0;
3019    return LHSRank > RHSRank ? 1 : -1;
3020  }
3021
3022  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
3023  if (LHSUnsigned) {
3024    // If the unsigned [LHS] type is larger, return it.
3025    if (LHSRank >= RHSRank)
3026      return 1;
3027
3028    // If the signed type can represent all values of the unsigned type, it
3029    // wins.  Because we are dealing with 2's complement and types that are
3030    // powers of two larger than each other, this is always safe.
3031    return -1;
3032  }
3033
3034  // If the unsigned [RHS] type is larger, return it.
3035  if (RHSRank >= LHSRank)
3036    return -1;
3037
3038  // If the signed type can represent all values of the unsigned type, it
3039  // wins.  Because we are dealing with 2's complement and types that are
3040  // powers of two larger than each other, this is always safe.
3041  return 1;
3042}
3043
3044static RecordDecl *
3045CreateRecordDecl(ASTContext &Ctx, RecordDecl::TagKind TK, DeclContext *DC,
3046                 SourceLocation L, IdentifierInfo *Id) {
3047  if (Ctx.getLangOptions().CPlusPlus)
3048    return CXXRecordDecl::Create(Ctx, TK, DC, L, Id);
3049  else
3050    return RecordDecl::Create(Ctx, TK, DC, L, Id);
3051}
3052
3053// getCFConstantStringType - Return the type used for constant CFStrings.
3054QualType ASTContext::getCFConstantStringType() {
3055  if (!CFConstantStringTypeDecl) {
3056    CFConstantStringTypeDecl =
3057      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3058                       &Idents.get("NSConstantString"));
3059    CFConstantStringTypeDecl->startDefinition();
3060
3061    QualType FieldTypes[4];
3062
3063    // const int *isa;
3064    FieldTypes[0] = getPointerType(IntTy.withConst());
3065    // int flags;
3066    FieldTypes[1] = IntTy;
3067    // const char *str;
3068    FieldTypes[2] = getPointerType(CharTy.withConst());
3069    // long length;
3070    FieldTypes[3] = LongTy;
3071
3072    // Create fields
3073    for (unsigned i = 0; i < 4; ++i) {
3074      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
3075                                           SourceLocation(), 0,
3076                                           FieldTypes[i], /*TInfo=*/0,
3077                                           /*BitWidth=*/0,
3078                                           /*Mutable=*/false);
3079      Field->setAccess(AS_public);
3080      CFConstantStringTypeDecl->addDecl(Field);
3081    }
3082
3083    CFConstantStringTypeDecl->completeDefinition();
3084  }
3085
3086  return getTagDeclType(CFConstantStringTypeDecl);
3087}
3088
3089void ASTContext::setCFConstantStringType(QualType T) {
3090  const RecordType *Rec = T->getAs<RecordType>();
3091  assert(Rec && "Invalid CFConstantStringType");
3092  CFConstantStringTypeDecl = Rec->getDecl();
3093}
3094
3095// getNSConstantStringType - Return the type used for constant NSStrings.
3096QualType ASTContext::getNSConstantStringType() {
3097  if (!NSConstantStringTypeDecl) {
3098    NSConstantStringTypeDecl =
3099    CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3100                     &Idents.get("__builtin_NSString"));
3101    NSConstantStringTypeDecl->startDefinition();
3102
3103    QualType FieldTypes[3];
3104
3105    // const int *isa;
3106    FieldTypes[0] = getPointerType(IntTy.withConst());
3107    // const char *str;
3108    FieldTypes[1] = getPointerType(CharTy.withConst());
3109    // unsigned int length;
3110    FieldTypes[2] = UnsignedIntTy;
3111
3112    // Create fields
3113    for (unsigned i = 0; i < 3; ++i) {
3114      FieldDecl *Field = FieldDecl::Create(*this, NSConstantStringTypeDecl,
3115                                           SourceLocation(), 0,
3116                                           FieldTypes[i], /*TInfo=*/0,
3117                                           /*BitWidth=*/0,
3118                                           /*Mutable=*/false);
3119      Field->setAccess(AS_public);
3120      NSConstantStringTypeDecl->addDecl(Field);
3121    }
3122
3123    NSConstantStringTypeDecl->completeDefinition();
3124  }
3125
3126  return getTagDeclType(NSConstantStringTypeDecl);
3127}
3128
3129void ASTContext::setNSConstantStringType(QualType T) {
3130  const RecordType *Rec = T->getAs<RecordType>();
3131  assert(Rec && "Invalid NSConstantStringType");
3132  NSConstantStringTypeDecl = Rec->getDecl();
3133}
3134
3135QualType ASTContext::getObjCFastEnumerationStateType() {
3136  if (!ObjCFastEnumerationStateTypeDecl) {
3137    ObjCFastEnumerationStateTypeDecl =
3138      CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3139                       &Idents.get("__objcFastEnumerationState"));
3140    ObjCFastEnumerationStateTypeDecl->startDefinition();
3141
3142    QualType FieldTypes[] = {
3143      UnsignedLongTy,
3144      getPointerType(ObjCIdTypedefType),
3145      getPointerType(UnsignedLongTy),
3146      getConstantArrayType(UnsignedLongTy,
3147                           llvm::APInt(32, 5), ArrayType::Normal, 0)
3148    };
3149
3150    for (size_t i = 0; i < 4; ++i) {
3151      FieldDecl *Field = FieldDecl::Create(*this,
3152                                           ObjCFastEnumerationStateTypeDecl,
3153                                           SourceLocation(), 0,
3154                                           FieldTypes[i], /*TInfo=*/0,
3155                                           /*BitWidth=*/0,
3156                                           /*Mutable=*/false);
3157      Field->setAccess(AS_public);
3158      ObjCFastEnumerationStateTypeDecl->addDecl(Field);
3159    }
3160
3161    ObjCFastEnumerationStateTypeDecl->completeDefinition();
3162  }
3163
3164  return getTagDeclType(ObjCFastEnumerationStateTypeDecl);
3165}
3166
3167QualType ASTContext::getBlockDescriptorType() {
3168  if (BlockDescriptorType)
3169    return getTagDeclType(BlockDescriptorType);
3170
3171  RecordDecl *T;
3172  // FIXME: Needs the FlagAppleBlock bit.
3173  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3174                       &Idents.get("__block_descriptor"));
3175  T->startDefinition();
3176
3177  QualType FieldTypes[] = {
3178    UnsignedLongTy,
3179    UnsignedLongTy,
3180  };
3181
3182  const char *FieldNames[] = {
3183    "reserved",
3184    "Size"
3185  };
3186
3187  for (size_t i = 0; i < 2; ++i) {
3188    FieldDecl *Field = FieldDecl::Create(*this,
3189                                         T,
3190                                         SourceLocation(),
3191                                         &Idents.get(FieldNames[i]),
3192                                         FieldTypes[i], /*TInfo=*/0,
3193                                         /*BitWidth=*/0,
3194                                         /*Mutable=*/false);
3195    Field->setAccess(AS_public);
3196    T->addDecl(Field);
3197  }
3198
3199  T->completeDefinition();
3200
3201  BlockDescriptorType = T;
3202
3203  return getTagDeclType(BlockDescriptorType);
3204}
3205
3206void ASTContext::setBlockDescriptorType(QualType T) {
3207  const RecordType *Rec = T->getAs<RecordType>();
3208  assert(Rec && "Invalid BlockDescriptorType");
3209  BlockDescriptorType = Rec->getDecl();
3210}
3211
3212QualType ASTContext::getBlockDescriptorExtendedType() {
3213  if (BlockDescriptorExtendedType)
3214    return getTagDeclType(BlockDescriptorExtendedType);
3215
3216  RecordDecl *T;
3217  // FIXME: Needs the FlagAppleBlock bit.
3218  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3219                       &Idents.get("__block_descriptor_withcopydispose"));
3220  T->startDefinition();
3221
3222  QualType FieldTypes[] = {
3223    UnsignedLongTy,
3224    UnsignedLongTy,
3225    getPointerType(VoidPtrTy),
3226    getPointerType(VoidPtrTy)
3227  };
3228
3229  const char *FieldNames[] = {
3230    "reserved",
3231    "Size",
3232    "CopyFuncPtr",
3233    "DestroyFuncPtr"
3234  };
3235
3236  for (size_t i = 0; i < 4; ++i) {
3237    FieldDecl *Field = FieldDecl::Create(*this,
3238                                         T,
3239                                         SourceLocation(),
3240                                         &Idents.get(FieldNames[i]),
3241                                         FieldTypes[i], /*TInfo=*/0,
3242                                         /*BitWidth=*/0,
3243                                         /*Mutable=*/false);
3244    Field->setAccess(AS_public);
3245    T->addDecl(Field);
3246  }
3247
3248  T->completeDefinition();
3249
3250  BlockDescriptorExtendedType = T;
3251
3252  return getTagDeclType(BlockDescriptorExtendedType);
3253}
3254
3255void ASTContext::setBlockDescriptorExtendedType(QualType T) {
3256  const RecordType *Rec = T->getAs<RecordType>();
3257  assert(Rec && "Invalid BlockDescriptorType");
3258  BlockDescriptorExtendedType = Rec->getDecl();
3259}
3260
3261bool ASTContext::BlockRequiresCopying(QualType Ty) {
3262  if (Ty->isBlockPointerType())
3263    return true;
3264  if (isObjCNSObjectType(Ty))
3265    return true;
3266  if (Ty->isObjCObjectPointerType())
3267    return true;
3268  return false;
3269}
3270
3271QualType ASTContext::BuildByRefType(llvm::StringRef DeclName, QualType Ty) {
3272  //  type = struct __Block_byref_1_X {
3273  //    void *__isa;
3274  //    struct __Block_byref_1_X *__forwarding;
3275  //    unsigned int __flags;
3276  //    unsigned int __size;
3277  //    void *__copy_helper;            // as needed
3278  //    void *__destroy_help            // as needed
3279  //    int X;
3280  //  } *
3281
3282  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
3283
3284  // FIXME: Move up
3285  llvm::SmallString<36> Name;
3286  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
3287                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
3288  RecordDecl *T;
3289  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3290                       &Idents.get(Name.str()));
3291  T->startDefinition();
3292  QualType Int32Ty = IntTy;
3293  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
3294  QualType FieldTypes[] = {
3295    getPointerType(VoidPtrTy),
3296    getPointerType(getTagDeclType(T)),
3297    Int32Ty,
3298    Int32Ty,
3299    getPointerType(VoidPtrTy),
3300    getPointerType(VoidPtrTy),
3301    Ty
3302  };
3303
3304  llvm::StringRef FieldNames[] = {
3305    "__isa",
3306    "__forwarding",
3307    "__flags",
3308    "__size",
3309    "__copy_helper",
3310    "__destroy_helper",
3311    DeclName,
3312  };
3313
3314  for (size_t i = 0; i < 7; ++i) {
3315    if (!HasCopyAndDispose && i >=4 && i <= 5)
3316      continue;
3317    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3318                                         &Idents.get(FieldNames[i]),
3319                                         FieldTypes[i], /*TInfo=*/0,
3320                                         /*BitWidth=*/0, /*Mutable=*/false);
3321    Field->setAccess(AS_public);
3322    T->addDecl(Field);
3323  }
3324
3325  T->completeDefinition();
3326
3327  return getPointerType(getTagDeclType(T));
3328}
3329
3330
3331QualType ASTContext::getBlockParmType(
3332  bool BlockHasCopyDispose,
3333  llvm::SmallVectorImpl<const Expr *> &Layout) {
3334
3335  // FIXME: Move up
3336  llvm::SmallString<36> Name;
3337  llvm::raw_svector_ostream(Name) << "__block_literal_"
3338                                  << ++UniqueBlockParmTypeID;
3339  RecordDecl *T;
3340  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, SourceLocation(),
3341                       &Idents.get(Name.str()));
3342  T->startDefinition();
3343  QualType FieldTypes[] = {
3344    getPointerType(VoidPtrTy),
3345    IntTy,
3346    IntTy,
3347    getPointerType(VoidPtrTy),
3348    (BlockHasCopyDispose ?
3349     getPointerType(getBlockDescriptorExtendedType()) :
3350     getPointerType(getBlockDescriptorType()))
3351  };
3352
3353  const char *FieldNames[] = {
3354    "__isa",
3355    "__flags",
3356    "__reserved",
3357    "__FuncPtr",
3358    "__descriptor"
3359  };
3360
3361  for (size_t i = 0; i < 5; ++i) {
3362    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3363                                         &Idents.get(FieldNames[i]),
3364                                         FieldTypes[i], /*TInfo=*/0,
3365                                         /*BitWidth=*/0, /*Mutable=*/false);
3366    Field->setAccess(AS_public);
3367    T->addDecl(Field);
3368  }
3369
3370  for (unsigned i = 0; i < Layout.size(); ++i) {
3371    const Expr *E = Layout[i];
3372
3373    QualType FieldType = E->getType();
3374    IdentifierInfo *FieldName = 0;
3375    if (isa<CXXThisExpr>(E)) {
3376      FieldName = &Idents.get("this");
3377    } else if (const BlockDeclRefExpr *BDRE = dyn_cast<BlockDeclRefExpr>(E)) {
3378      const ValueDecl *D = BDRE->getDecl();
3379      FieldName = D->getIdentifier();
3380      if (BDRE->isByRef())
3381        FieldType = BuildByRefType(D->getName(), FieldType);
3382    } else {
3383      // Padding.
3384      assert(isa<ConstantArrayType>(FieldType) &&
3385             isa<DeclRefExpr>(E) &&
3386             !cast<DeclRefExpr>(E)->getDecl()->getDeclName() &&
3387             "doesn't match characteristics of padding decl");
3388    }
3389
3390    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
3391                                         FieldName, FieldType, /*TInfo=*/0,
3392                                         /*BitWidth=*/0, /*Mutable=*/false);
3393    Field->setAccess(AS_public);
3394    T->addDecl(Field);
3395  }
3396
3397  T->completeDefinition();
3398
3399  return getPointerType(getTagDeclType(T));
3400}
3401
3402void ASTContext::setObjCFastEnumerationStateType(QualType T) {
3403  const RecordType *Rec = T->getAs<RecordType>();
3404  assert(Rec && "Invalid ObjCFAstEnumerationStateType");
3405  ObjCFastEnumerationStateTypeDecl = Rec->getDecl();
3406}
3407
3408// This returns true if a type has been typedefed to BOOL:
3409// typedef <type> BOOL;
3410static bool isTypeTypedefedAsBOOL(QualType T) {
3411  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
3412    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
3413      return II->isStr("BOOL");
3414
3415  return false;
3416}
3417
3418/// getObjCEncodingTypeSize returns size of type for objective-c encoding
3419/// purpose.
3420CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) {
3421  CharUnits sz = getTypeSizeInChars(type);
3422
3423  // Make all integer and enum types at least as large as an int
3424  if (sz.isPositive() && type->isIntegralOrEnumerationType())
3425    sz = std::max(sz, getTypeSizeInChars(IntTy));
3426  // Treat arrays as pointers, since that's how they're passed in.
3427  else if (type->isArrayType())
3428    sz = getTypeSizeInChars(VoidPtrTy);
3429  return sz;
3430}
3431
3432static inline
3433std::string charUnitsToString(const CharUnits &CU) {
3434  return llvm::itostr(CU.getQuantity());
3435}
3436
3437/// getObjCEncodingForBlockDecl - Return the encoded type for this block
3438/// declaration.
3439void ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr,
3440                                             std::string& S) {
3441  const BlockDecl *Decl = Expr->getBlockDecl();
3442  QualType BlockTy =
3443      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
3444  // Encode result type.
3445  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
3446  // Compute size of all parameters.
3447  // Start with computing size of a pointer in number of bytes.
3448  // FIXME: There might(should) be a better way of doing this computation!
3449  SourceLocation Loc;
3450  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3451  CharUnits ParmOffset = PtrSize;
3452  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
3453       E = Decl->param_end(); PI != E; ++PI) {
3454    QualType PType = (*PI)->getType();
3455    CharUnits sz = getObjCEncodingTypeSize(PType);
3456    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
3457    ParmOffset += sz;
3458  }
3459  // Size of the argument frame
3460  S += charUnitsToString(ParmOffset);
3461  // Block pointer and offset.
3462  S += "@?0";
3463  ParmOffset = PtrSize;
3464
3465  // Argument types.
3466  ParmOffset = PtrSize;
3467  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
3468       Decl->param_end(); PI != E; ++PI) {
3469    ParmVarDecl *PVDecl = *PI;
3470    QualType PType = PVDecl->getOriginalType();
3471    if (const ArrayType *AT =
3472          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3473      // Use array's original type only if it has known number of
3474      // elements.
3475      if (!isa<ConstantArrayType>(AT))
3476        PType = PVDecl->getType();
3477    } else if (PType->isFunctionType())
3478      PType = PVDecl->getType();
3479    getObjCEncodingForType(PType, S);
3480    S += charUnitsToString(ParmOffset);
3481    ParmOffset += getObjCEncodingTypeSize(PType);
3482  }
3483}
3484
3485/// getObjCEncodingForMethodDecl - Return the encoded type for this method
3486/// declaration.
3487void ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
3488                                              std::string& S) {
3489  // FIXME: This is not very efficient.
3490  // Encode type qualifer, 'in', 'inout', etc. for the return type.
3491  getObjCEncodingForTypeQualifier(Decl->getObjCDeclQualifier(), S);
3492  // Encode result type.
3493  getObjCEncodingForType(Decl->getResultType(), S);
3494  // Compute size of all parameters.
3495  // Start with computing size of a pointer in number of bytes.
3496  // FIXME: There might(should) be a better way of doing this computation!
3497  SourceLocation Loc;
3498  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
3499  // The first two arguments (self and _cmd) are pointers; account for
3500  // their size.
3501  CharUnits ParmOffset = 2 * PtrSize;
3502  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3503       E = Decl->sel_param_end(); PI != E; ++PI) {
3504    QualType PType = (*PI)->getType();
3505    CharUnits sz = getObjCEncodingTypeSize(PType);
3506    assert (sz.isPositive() &&
3507        "getObjCEncodingForMethodDecl - Incomplete param type");
3508    ParmOffset += sz;
3509  }
3510  S += charUnitsToString(ParmOffset);
3511  S += "@0:";
3512  S += charUnitsToString(PtrSize);
3513
3514  // Argument types.
3515  ParmOffset = 2 * PtrSize;
3516  for (ObjCMethodDecl::param_iterator PI = Decl->param_begin(),
3517       E = Decl->sel_param_end(); PI != E; ++PI) {
3518    ParmVarDecl *PVDecl = *PI;
3519    QualType PType = PVDecl->getOriginalType();
3520    if (const ArrayType *AT =
3521          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
3522      // Use array's original type only if it has known number of
3523      // elements.
3524      if (!isa<ConstantArrayType>(AT))
3525        PType = PVDecl->getType();
3526    } else if (PType->isFunctionType())
3527      PType = PVDecl->getType();
3528    // Process argument qualifiers for user supplied arguments; such as,
3529    // 'in', 'inout', etc.
3530    getObjCEncodingForTypeQualifier(PVDecl->getObjCDeclQualifier(), S);
3531    getObjCEncodingForType(PType, S);
3532    S += charUnitsToString(ParmOffset);
3533    ParmOffset += getObjCEncodingTypeSize(PType);
3534  }
3535}
3536
3537/// getObjCEncodingForPropertyDecl - Return the encoded type for this
3538/// property declaration. If non-NULL, Container must be either an
3539/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
3540/// NULL when getting encodings for protocol properties.
3541/// Property attributes are stored as a comma-delimited C string. The simple
3542/// attributes readonly and bycopy are encoded as single characters. The
3543/// parametrized attributes, getter=name, setter=name, and ivar=name, are
3544/// encoded as single characters, followed by an identifier. Property types
3545/// are also encoded as a parametrized attribute. The characters used to encode
3546/// these attributes are defined by the following enumeration:
3547/// @code
3548/// enum PropertyAttributes {
3549/// kPropertyReadOnly = 'R',   // property is read-only.
3550/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
3551/// kPropertyByref = '&',  // property is a reference to the value last assigned
3552/// kPropertyDynamic = 'D',    // property is dynamic
3553/// kPropertyGetter = 'G',     // followed by getter selector name
3554/// kPropertySetter = 'S',     // followed by setter selector name
3555/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
3556/// kPropertyType = 't'              // followed by old-style type encoding.
3557/// kPropertyWeak = 'W'              // 'weak' property
3558/// kPropertyStrong = 'P'            // property GC'able
3559/// kPropertyNonAtomic = 'N'         // property non-atomic
3560/// };
3561/// @endcode
3562void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
3563                                                const Decl *Container,
3564                                                std::string& S) {
3565  // Collect information from the property implementation decl(s).
3566  bool Dynamic = false;
3567  ObjCPropertyImplDecl *SynthesizePID = 0;
3568
3569  // FIXME: Duplicated code due to poor abstraction.
3570  if (Container) {
3571    if (const ObjCCategoryImplDecl *CID =
3572        dyn_cast<ObjCCategoryImplDecl>(Container)) {
3573      for (ObjCCategoryImplDecl::propimpl_iterator
3574             i = CID->propimpl_begin(), e = CID->propimpl_end();
3575           i != e; ++i) {
3576        ObjCPropertyImplDecl *PID = *i;
3577        if (PID->getPropertyDecl() == PD) {
3578          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3579            Dynamic = true;
3580          } else {
3581            SynthesizePID = PID;
3582          }
3583        }
3584      }
3585    } else {
3586      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
3587      for (ObjCCategoryImplDecl::propimpl_iterator
3588             i = OID->propimpl_begin(), e = OID->propimpl_end();
3589           i != e; ++i) {
3590        ObjCPropertyImplDecl *PID = *i;
3591        if (PID->getPropertyDecl() == PD) {
3592          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
3593            Dynamic = true;
3594          } else {
3595            SynthesizePID = PID;
3596          }
3597        }
3598      }
3599    }
3600  }
3601
3602  // FIXME: This is not very efficient.
3603  S = "T";
3604
3605  // Encode result type.
3606  // GCC has some special rules regarding encoding of properties which
3607  // closely resembles encoding of ivars.
3608  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
3609                             true /* outermost type */,
3610                             true /* encoding for property */);
3611
3612  if (PD->isReadOnly()) {
3613    S += ",R";
3614  } else {
3615    switch (PD->getSetterKind()) {
3616    case ObjCPropertyDecl::Assign: break;
3617    case ObjCPropertyDecl::Copy:   S += ",C"; break;
3618    case ObjCPropertyDecl::Retain: S += ",&"; break;
3619    }
3620  }
3621
3622  // It really isn't clear at all what this means, since properties
3623  // are "dynamic by default".
3624  if (Dynamic)
3625    S += ",D";
3626
3627  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
3628    S += ",N";
3629
3630  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
3631    S += ",G";
3632    S += PD->getGetterName().getAsString();
3633  }
3634
3635  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
3636    S += ",S";
3637    S += PD->getSetterName().getAsString();
3638  }
3639
3640  if (SynthesizePID) {
3641    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
3642    S += ",V";
3643    S += OID->getNameAsString();
3644  }
3645
3646  // FIXME: OBJCGC: weak & strong
3647}
3648
3649/// getLegacyIntegralTypeEncoding -
3650/// Another legacy compatibility encoding: 32-bit longs are encoded as
3651/// 'l' or 'L' , but not always.  For typedefs, we need to use
3652/// 'i' or 'I' instead if encoding a struct field, or a pointer!
3653///
3654void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
3655  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
3656    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
3657      if (BT->getKind() == BuiltinType::ULong &&
3658          ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3659        PointeeTy = UnsignedIntTy;
3660      else
3661        if (BT->getKind() == BuiltinType::Long &&
3662            ((const_cast<ASTContext *>(this))->getIntWidth(PointeeTy) == 32))
3663          PointeeTy = IntTy;
3664    }
3665  }
3666}
3667
3668void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
3669                                        const FieldDecl *Field) {
3670  // We follow the behavior of gcc, expanding structures which are
3671  // directly pointed to, and expanding embedded structures. Note that
3672  // these rules are sufficient to prevent recursive encoding of the
3673  // same type.
3674  getObjCEncodingForTypeImpl(T, S, true, true, Field,
3675                             true /* outermost type */);
3676}
3677
3678static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
3679    switch (T->getAs<BuiltinType>()->getKind()) {
3680    default: assert(0 && "Unhandled builtin type kind");
3681    case BuiltinType::Void:       return 'v';
3682    case BuiltinType::Bool:       return 'B';
3683    case BuiltinType::Char_U:
3684    case BuiltinType::UChar:      return 'C';
3685    case BuiltinType::UShort:     return 'S';
3686    case BuiltinType::UInt:       return 'I';
3687    case BuiltinType::ULong:
3688        return
3689          (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'L' : 'Q';
3690    case BuiltinType::UInt128:    return 'T';
3691    case BuiltinType::ULongLong:  return 'Q';
3692    case BuiltinType::Char_S:
3693    case BuiltinType::SChar:      return 'c';
3694    case BuiltinType::Short:      return 's';
3695    case BuiltinType::WChar:
3696    case BuiltinType::Int:        return 'i';
3697    case BuiltinType::Long:
3698      return
3699        (const_cast<ASTContext *>(C))->getIntWidth(T) == 32 ? 'l' : 'q';
3700    case BuiltinType::LongLong:   return 'q';
3701    case BuiltinType::Int128:     return 't';
3702    case BuiltinType::Float:      return 'f';
3703    case BuiltinType::Double:     return 'd';
3704    case BuiltinType::LongDouble: return 'D';
3705    }
3706}
3707
3708static void EncodeBitField(const ASTContext *Context, std::string& S,
3709                           QualType T, const FieldDecl *FD) {
3710  const Expr *E = FD->getBitWidth();
3711  assert(E && "bitfield width not there - getObjCEncodingForTypeImpl");
3712  ASTContext *Ctx = const_cast<ASTContext*>(Context);
3713  S += 'b';
3714  // The NeXT runtime encodes bit fields as b followed by the number of bits.
3715  // The GNU runtime requires more information; bitfields are encoded as b,
3716  // then the offset (in bits) of the first element, then the type of the
3717  // bitfield, then the size in bits.  For example, in this structure:
3718  //
3719  // struct
3720  // {
3721  //    int integer;
3722  //    int flags:2;
3723  // };
3724  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
3725  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
3726  // information is not especially sensible, but we're stuck with it for
3727  // compatibility with GCC, although providing it breaks anything that
3728  // actually uses runtime introspection and wants to work on both runtimes...
3729  if (!Ctx->getLangOptions().NeXTRuntime) {
3730    const RecordDecl *RD = FD->getParent();
3731    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
3732    // FIXME: This same linear search is also used in ExprConstant - it might
3733    // be better if the FieldDecl stored its offset.  We'd be increasing the
3734    // size of the object slightly, but saving some time every time it is used.
3735    unsigned i = 0;
3736    for (RecordDecl::field_iterator Field = RD->field_begin(),
3737                                 FieldEnd = RD->field_end();
3738         Field != FieldEnd; (void)++Field, ++i) {
3739      if (*Field == FD)
3740        break;
3741    }
3742    S += llvm::utostr(RL.getFieldOffset(i));
3743    S += ObjCEncodingForPrimitiveKind(Context, T);
3744  }
3745  unsigned N = E->EvaluateAsInt(*Ctx).getZExtValue();
3746  S += llvm::utostr(N);
3747}
3748
3749// FIXME: Use SmallString for accumulating string.
3750void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
3751                                            bool ExpandPointedToStructures,
3752                                            bool ExpandStructures,
3753                                            const FieldDecl *FD,
3754                                            bool OutermostType,
3755                                            bool EncodingProperty) {
3756  if (T->getAs<BuiltinType>()) {
3757    if (FD && FD->isBitField())
3758      return EncodeBitField(this, S, T, FD);
3759    S += ObjCEncodingForPrimitiveKind(this, T);
3760    return;
3761  }
3762
3763  if (const ComplexType *CT = T->getAs<ComplexType>()) {
3764    S += 'j';
3765    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
3766                               false);
3767    return;
3768  }
3769
3770  // encoding for pointer or r3eference types.
3771  QualType PointeeTy;
3772  if (const PointerType *PT = T->getAs<PointerType>()) {
3773    if (PT->isObjCSelType()) {
3774      S += ':';
3775      return;
3776    }
3777    PointeeTy = PT->getPointeeType();
3778  }
3779  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
3780    PointeeTy = RT->getPointeeType();
3781  if (!PointeeTy.isNull()) {
3782    bool isReadOnly = false;
3783    // For historical/compatibility reasons, the read-only qualifier of the
3784    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
3785    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
3786    // Also, do not emit the 'r' for anything but the outermost type!
3787    if (isa<TypedefType>(T.getTypePtr())) {
3788      if (OutermostType && T.isConstQualified()) {
3789        isReadOnly = true;
3790        S += 'r';
3791      }
3792    } else if (OutermostType) {
3793      QualType P = PointeeTy;
3794      while (P->getAs<PointerType>())
3795        P = P->getAs<PointerType>()->getPointeeType();
3796      if (P.isConstQualified()) {
3797        isReadOnly = true;
3798        S += 'r';
3799      }
3800    }
3801    if (isReadOnly) {
3802      // Another legacy compatibility encoding. Some ObjC qualifier and type
3803      // combinations need to be rearranged.
3804      // Rewrite "in const" from "nr" to "rn"
3805      if (llvm::StringRef(S).endswith("nr"))
3806        S.replace(S.end()-2, S.end(), "rn");
3807    }
3808
3809    if (PointeeTy->isCharType()) {
3810      // char pointer types should be encoded as '*' unless it is a
3811      // type that has been typedef'd to 'BOOL'.
3812      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
3813        S += '*';
3814        return;
3815      }
3816    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
3817      // GCC binary compat: Need to convert "struct objc_class *" to "#".
3818      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
3819        S += '#';
3820        return;
3821      }
3822      // GCC binary compat: Need to convert "struct objc_object *" to "@".
3823      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
3824        S += '@';
3825        return;
3826      }
3827      // fall through...
3828    }
3829    S += '^';
3830    getLegacyIntegralTypeEncoding(PointeeTy);
3831
3832    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
3833                               NULL);
3834    return;
3835  }
3836
3837  if (const ArrayType *AT =
3838      // Ignore type qualifiers etc.
3839        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
3840    if (isa<IncompleteArrayType>(AT)) {
3841      // Incomplete arrays are encoded as a pointer to the array element.
3842      S += '^';
3843
3844      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3845                                 false, ExpandStructures, FD);
3846    } else {
3847      S += '[';
3848
3849      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
3850        S += llvm::utostr(CAT->getSize().getZExtValue());
3851      else {
3852        //Variable length arrays are encoded as a regular array with 0 elements.
3853        assert(isa<VariableArrayType>(AT) && "Unknown array type!");
3854        S += '0';
3855      }
3856
3857      getObjCEncodingForTypeImpl(AT->getElementType(), S,
3858                                 false, ExpandStructures, FD);
3859      S += ']';
3860    }
3861    return;
3862  }
3863
3864  if (T->getAs<FunctionType>()) {
3865    S += '?';
3866    return;
3867  }
3868
3869  if (const RecordType *RTy = T->getAs<RecordType>()) {
3870    RecordDecl *RDecl = RTy->getDecl();
3871    S += RDecl->isUnion() ? '(' : '{';
3872    // Anonymous structures print as '?'
3873    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
3874      S += II->getName();
3875      if (ClassTemplateSpecializationDecl *Spec
3876          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
3877        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
3878        std::string TemplateArgsStr
3879          = TemplateSpecializationType::PrintTemplateArgumentList(
3880                                            TemplateArgs.getFlatArgumentList(),
3881                                            TemplateArgs.flat_size(),
3882                                            (*this).PrintingPolicy);
3883
3884        S += TemplateArgsStr;
3885      }
3886    } else {
3887      S += '?';
3888    }
3889    if (ExpandStructures) {
3890      S += '=';
3891      for (RecordDecl::field_iterator Field = RDecl->field_begin(),
3892                                   FieldEnd = RDecl->field_end();
3893           Field != FieldEnd; ++Field) {
3894        if (FD) {
3895          S += '"';
3896          S += Field->getNameAsString();
3897          S += '"';
3898        }
3899
3900        // Special case bit-fields.
3901        if (Field->isBitField()) {
3902          getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
3903                                     (*Field));
3904        } else {
3905          QualType qt = Field->getType();
3906          getLegacyIntegralTypeEncoding(qt);
3907          getObjCEncodingForTypeImpl(qt, S, false, true,
3908                                     FD);
3909        }
3910      }
3911    }
3912    S += RDecl->isUnion() ? ')' : '}';
3913    return;
3914  }
3915
3916  if (T->isEnumeralType()) {
3917    if (FD && FD->isBitField())
3918      EncodeBitField(this, S, T, FD);
3919    else
3920      S += 'i';
3921    return;
3922  }
3923
3924  if (T->isBlockPointerType()) {
3925    S += "@?"; // Unlike a pointer-to-function, which is "^?".
3926    return;
3927  }
3928
3929  // Ignore protocol qualifiers when mangling at this level.
3930  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
3931    T = OT->getBaseType();
3932
3933  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
3934    // @encode(class_name)
3935    ObjCInterfaceDecl *OI = OIT->getDecl();
3936    S += '{';
3937    const IdentifierInfo *II = OI->getIdentifier();
3938    S += II->getName();
3939    S += '=';
3940    llvm::SmallVector<ObjCIvarDecl*, 32> Ivars;
3941    DeepCollectObjCIvars(OI, true, Ivars);
3942    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
3943      FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
3944      if (Field->isBitField())
3945        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
3946      else
3947        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
3948    }
3949    S += '}';
3950    return;
3951  }
3952
3953  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
3954    if (OPT->isObjCIdType()) {
3955      S += '@';
3956      return;
3957    }
3958
3959    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
3960      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
3961      // Since this is a binary compatibility issue, need to consult with runtime
3962      // folks. Fortunately, this is a *very* obsure construct.
3963      S += '#';
3964      return;
3965    }
3966
3967    if (OPT->isObjCQualifiedIdType()) {
3968      getObjCEncodingForTypeImpl(getObjCIdType(), S,
3969                                 ExpandPointedToStructures,
3970                                 ExpandStructures, FD);
3971      if (FD || EncodingProperty) {
3972        // Note that we do extended encoding of protocol qualifer list
3973        // Only when doing ivar or property encoding.
3974        S += '"';
3975        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
3976             E = OPT->qual_end(); I != E; ++I) {
3977          S += '<';
3978          S += (*I)->getNameAsString();
3979          S += '>';
3980        }
3981        S += '"';
3982      }
3983      return;
3984    }
3985
3986    QualType PointeeTy = OPT->getPointeeType();
3987    if (!EncodingProperty &&
3988        isa<TypedefType>(PointeeTy.getTypePtr())) {
3989      // Another historical/compatibility reason.
3990      // We encode the underlying type which comes out as
3991      // {...};
3992      S += '^';
3993      getObjCEncodingForTypeImpl(PointeeTy, S,
3994                                 false, ExpandPointedToStructures,
3995                                 NULL);
3996      return;
3997    }
3998
3999    S += '@';
4000    if (OPT->getInterfaceDecl() && (FD || EncodingProperty)) {
4001      S += '"';
4002      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
4003      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
4004           E = OPT->qual_end(); I != E; ++I) {
4005        S += '<';
4006        S += (*I)->getNameAsString();
4007        S += '>';
4008      }
4009      S += '"';
4010    }
4011    return;
4012  }
4013
4014  // gcc just blithely ignores member pointers.
4015  // TODO: maybe there should be a mangling for these
4016  if (T->getAs<MemberPointerType>())
4017    return;
4018
4019  if (T->isVectorType()) {
4020    // This matches gcc's encoding, even though technically it is
4021    // insufficient.
4022    // FIXME. We should do a better job than gcc.
4023    return;
4024  }
4025
4026  assert(0 && "@encode for type not implemented!");
4027}
4028
4029void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
4030                                                 std::string& S) const {
4031  if (QT & Decl::OBJC_TQ_In)
4032    S += 'n';
4033  if (QT & Decl::OBJC_TQ_Inout)
4034    S += 'N';
4035  if (QT & Decl::OBJC_TQ_Out)
4036    S += 'o';
4037  if (QT & Decl::OBJC_TQ_Bycopy)
4038    S += 'O';
4039  if (QT & Decl::OBJC_TQ_Byref)
4040    S += 'R';
4041  if (QT & Decl::OBJC_TQ_Oneway)
4042    S += 'V';
4043}
4044
4045void ASTContext::setBuiltinVaListType(QualType T) {
4046  assert(BuiltinVaListType.isNull() && "__builtin_va_list type already set!");
4047
4048  BuiltinVaListType = T;
4049}
4050
4051void ASTContext::setObjCIdType(QualType T) {
4052  ObjCIdTypedefType = T;
4053}
4054
4055void ASTContext::setObjCSelType(QualType T) {
4056  ObjCSelTypedefType = T;
4057}
4058
4059void ASTContext::setObjCProtoType(QualType QT) {
4060  ObjCProtoType = QT;
4061}
4062
4063void ASTContext::setObjCClassType(QualType T) {
4064  ObjCClassTypedefType = T;
4065}
4066
4067void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
4068  assert(ObjCConstantStringType.isNull() &&
4069         "'NSConstantString' type already set!");
4070
4071  ObjCConstantStringType = getObjCInterfaceType(Decl);
4072}
4073
4074/// \brief Retrieve the template name that corresponds to a non-empty
4075/// lookup.
4076TemplateName ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
4077                                                   UnresolvedSetIterator End) {
4078  unsigned size = End - Begin;
4079  assert(size > 1 && "set is not overloaded!");
4080
4081  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
4082                          size * sizeof(FunctionTemplateDecl*));
4083  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
4084
4085  NamedDecl **Storage = OT->getStorage();
4086  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
4087    NamedDecl *D = *I;
4088    assert(isa<FunctionTemplateDecl>(D) ||
4089           (isa<UsingShadowDecl>(D) &&
4090            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
4091    *Storage++ = D;
4092  }
4093
4094  return TemplateName(OT);
4095}
4096
4097/// \brief Retrieve the template name that represents a qualified
4098/// template name such as \c std::vector.
4099TemplateName ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
4100                                                  bool TemplateKeyword,
4101                                                  TemplateDecl *Template) {
4102  // FIXME: Canonicalization?
4103  llvm::FoldingSetNodeID ID;
4104  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
4105
4106  void *InsertPos = 0;
4107  QualifiedTemplateName *QTN =
4108    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4109  if (!QTN) {
4110    QTN = new (*this,4) QualifiedTemplateName(NNS, TemplateKeyword, Template);
4111    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
4112  }
4113
4114  return TemplateName(QTN);
4115}
4116
4117/// \brief Retrieve the template name that represents a dependent
4118/// template name such as \c MetaFun::template apply.
4119TemplateName ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4120                                                  const IdentifierInfo *Name) {
4121  assert((!NNS || NNS->isDependent()) &&
4122         "Nested name specifier must be dependent");
4123
4124  llvm::FoldingSetNodeID ID;
4125  DependentTemplateName::Profile(ID, NNS, Name);
4126
4127  void *InsertPos = 0;
4128  DependentTemplateName *QTN =
4129    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4130
4131  if (QTN)
4132    return TemplateName(QTN);
4133
4134  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4135  if (CanonNNS == NNS) {
4136    QTN = new (*this,4) DependentTemplateName(NNS, Name);
4137  } else {
4138    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
4139    QTN = new (*this,4) DependentTemplateName(NNS, Name, Canon);
4140    DependentTemplateName *CheckQTN =
4141      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4142    assert(!CheckQTN && "Dependent type name canonicalization broken");
4143    (void)CheckQTN;
4144  }
4145
4146  DependentTemplateNames.InsertNode(QTN, InsertPos);
4147  return TemplateName(QTN);
4148}
4149
4150/// \brief Retrieve the template name that represents a dependent
4151/// template name such as \c MetaFun::template operator+.
4152TemplateName
4153ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
4154                                     OverloadedOperatorKind Operator) {
4155  assert((!NNS || NNS->isDependent()) &&
4156         "Nested name specifier must be dependent");
4157
4158  llvm::FoldingSetNodeID ID;
4159  DependentTemplateName::Profile(ID, NNS, Operator);
4160
4161  void *InsertPos = 0;
4162  DependentTemplateName *QTN
4163    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4164
4165  if (QTN)
4166    return TemplateName(QTN);
4167
4168  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
4169  if (CanonNNS == NNS) {
4170    QTN = new (*this,4) DependentTemplateName(NNS, Operator);
4171  } else {
4172    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
4173    QTN = new (*this,4) DependentTemplateName(NNS, Operator, Canon);
4174
4175    DependentTemplateName *CheckQTN
4176      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
4177    assert(!CheckQTN && "Dependent template name canonicalization broken");
4178    (void)CheckQTN;
4179  }
4180
4181  DependentTemplateNames.InsertNode(QTN, InsertPos);
4182  return TemplateName(QTN);
4183}
4184
4185/// getFromTargetType - Given one of the integer types provided by
4186/// TargetInfo, produce the corresponding type. The unsigned @p Type
4187/// is actually a value of type @c TargetInfo::IntType.
4188CanQualType ASTContext::getFromTargetType(unsigned Type) const {
4189  switch (Type) {
4190  case TargetInfo::NoInt: return CanQualType();
4191  case TargetInfo::SignedShort: return ShortTy;
4192  case TargetInfo::UnsignedShort: return UnsignedShortTy;
4193  case TargetInfo::SignedInt: return IntTy;
4194  case TargetInfo::UnsignedInt: return UnsignedIntTy;
4195  case TargetInfo::SignedLong: return LongTy;
4196  case TargetInfo::UnsignedLong: return UnsignedLongTy;
4197  case TargetInfo::SignedLongLong: return LongLongTy;
4198  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
4199  }
4200
4201  assert(false && "Unhandled TargetInfo::IntType value");
4202  return CanQualType();
4203}
4204
4205//===----------------------------------------------------------------------===//
4206//                        Type Predicates.
4207//===----------------------------------------------------------------------===//
4208
4209/// isObjCNSObjectType - Return true if this is an NSObject object using
4210/// NSObject attribute on a c-style pointer type.
4211/// FIXME - Make it work directly on types.
4212/// FIXME: Move to Type.
4213///
4214bool ASTContext::isObjCNSObjectType(QualType Ty) const {
4215  if (TypedefType *TDT = dyn_cast<TypedefType>(Ty)) {
4216    if (TypedefDecl *TD = TDT->getDecl())
4217      if (TD->getAttr<ObjCNSObjectAttr>())
4218        return true;
4219  }
4220  return false;
4221}
4222
4223/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
4224/// garbage collection attribute.
4225///
4226Qualifiers::GC ASTContext::getObjCGCAttrKind(const QualType &Ty) const {
4227  Qualifiers::GC GCAttrs = Qualifiers::GCNone;
4228  if (getLangOptions().ObjC1 &&
4229      getLangOptions().getGCMode() != LangOptions::NonGC) {
4230    GCAttrs = Ty.getObjCGCAttr();
4231    // Default behavious under objective-c's gc is for objective-c pointers
4232    // (or pointers to them) be treated as though they were declared
4233    // as __strong.
4234    if (GCAttrs == Qualifiers::GCNone) {
4235      if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4236        GCAttrs = Qualifiers::Strong;
4237      else if (Ty->isPointerType())
4238        return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
4239    }
4240    // Non-pointers have none gc'able attribute regardless of the attribute
4241    // set on them.
4242    else if (!Ty->isAnyPointerType() && !Ty->isBlockPointerType())
4243      return Qualifiers::GCNone;
4244  }
4245  return GCAttrs;
4246}
4247
4248//===----------------------------------------------------------------------===//
4249//                        Type Compatibility Testing
4250//===----------------------------------------------------------------------===//
4251
4252/// areCompatVectorTypes - Return true if the two specified vector types are
4253/// compatible.
4254static bool areCompatVectorTypes(const VectorType *LHS,
4255                                 const VectorType *RHS) {
4256  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
4257  return LHS->getElementType() == RHS->getElementType() &&
4258         LHS->getNumElements() == RHS->getNumElements();
4259}
4260
4261bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
4262                                          QualType SecondVec) {
4263  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
4264  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
4265
4266  if (hasSameUnqualifiedType(FirstVec, SecondVec))
4267    return true;
4268
4269  // AltiVec vectors types are identical to equivalent GCC vector types
4270  const VectorType *First = FirstVec->getAs<VectorType>();
4271  const VectorType *Second = SecondVec->getAs<VectorType>();
4272  if ((((First->getAltiVecSpecific() == VectorType::AltiVec) &&
4273        (Second->getAltiVecSpecific() == VectorType::NotAltiVec)) ||
4274       ((First->getAltiVecSpecific() == VectorType::NotAltiVec) &&
4275        (Second->getAltiVecSpecific() == VectorType::AltiVec))) &&
4276      hasSameType(First->getElementType(), Second->getElementType()) &&
4277      (First->getNumElements() == Second->getNumElements()))
4278    return true;
4279
4280  return false;
4281}
4282
4283//===----------------------------------------------------------------------===//
4284// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
4285//===----------------------------------------------------------------------===//
4286
4287/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
4288/// inheritance hierarchy of 'rProto'.
4289bool ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
4290                                                ObjCProtocolDecl *rProto) {
4291  if (lProto == rProto)
4292    return true;
4293  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
4294       E = rProto->protocol_end(); PI != E; ++PI)
4295    if (ProtocolCompatibleWithProtocol(lProto, *PI))
4296      return true;
4297  return false;
4298}
4299
4300/// QualifiedIdConformsQualifiedId - compare id<p,...> with id<p1,...>
4301/// return true if lhs's protocols conform to rhs's protocol; false
4302/// otherwise.
4303bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
4304  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
4305    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
4306  return false;
4307}
4308
4309/// ObjCQualifiedClassTypesAreCompatible - compare  Class<p,...> and
4310/// Class<p1, ...>.
4311bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
4312                                                      QualType rhs) {
4313  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
4314  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4315  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
4316
4317  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4318       E = lhsQID->qual_end(); I != E; ++I) {
4319    bool match = false;
4320    ObjCProtocolDecl *lhsProto = *I;
4321    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4322         E = rhsOPT->qual_end(); J != E; ++J) {
4323      ObjCProtocolDecl *rhsProto = *J;
4324      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
4325        match = true;
4326        break;
4327      }
4328    }
4329    if (!match)
4330      return false;
4331  }
4332  return true;
4333}
4334
4335/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
4336/// ObjCQualifiedIDType.
4337bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
4338                                                   bool compare) {
4339  // Allow id<P..> and an 'id' or void* type in all cases.
4340  if (lhs->isVoidPointerType() ||
4341      lhs->isObjCIdType() || lhs->isObjCClassType())
4342    return true;
4343  else if (rhs->isVoidPointerType() ||
4344           rhs->isObjCIdType() || rhs->isObjCClassType())
4345    return true;
4346
4347  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
4348    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
4349
4350    if (!rhsOPT) return false;
4351
4352    if (rhsOPT->qual_empty()) {
4353      // If the RHS is a unqualified interface pointer "NSString*",
4354      // make sure we check the class hierarchy.
4355      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4356        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4357             E = lhsQID->qual_end(); I != E; ++I) {
4358          // when comparing an id<P> on lhs with a static type on rhs,
4359          // see if static class implements all of id's protocols, directly or
4360          // through its super class and categories.
4361          if (!rhsID->ClassImplementsProtocol(*I, true))
4362            return false;
4363        }
4364      }
4365      // If there are no qualifiers and no interface, we have an 'id'.
4366      return true;
4367    }
4368    // Both the right and left sides have qualifiers.
4369    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4370         E = lhsQID->qual_end(); I != E; ++I) {
4371      ObjCProtocolDecl *lhsProto = *I;
4372      bool match = false;
4373
4374      // when comparing an id<P> on lhs with a static type on rhs,
4375      // see if static class implements all of id's protocols, directly or
4376      // through its super class and categories.
4377      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
4378           E = rhsOPT->qual_end(); J != E; ++J) {
4379        ObjCProtocolDecl *rhsProto = *J;
4380        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4381            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4382          match = true;
4383          break;
4384        }
4385      }
4386      // If the RHS is a qualified interface pointer "NSString<P>*",
4387      // make sure we check the class hierarchy.
4388      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
4389        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
4390             E = lhsQID->qual_end(); I != E; ++I) {
4391          // when comparing an id<P> on lhs with a static type on rhs,
4392          // see if static class implements all of id's protocols, directly or
4393          // through its super class and categories.
4394          if (rhsID->ClassImplementsProtocol(*I, true)) {
4395            match = true;
4396            break;
4397          }
4398        }
4399      }
4400      if (!match)
4401        return false;
4402    }
4403
4404    return true;
4405  }
4406
4407  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
4408  assert(rhsQID && "One of the LHS/RHS should be id<x>");
4409
4410  if (const ObjCObjectPointerType *lhsOPT =
4411        lhs->getAsObjCInterfacePointerType()) {
4412    if (lhsOPT->qual_empty()) {
4413      bool match = false;
4414      if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
4415        for (ObjCObjectPointerType::qual_iterator I = rhsQID->qual_begin(),
4416             E = rhsQID->qual_end(); I != E; ++I) {
4417          // when comparing an id<P> on rhs with a static type on lhs,
4418          // static class must implement all of id's protocols directly or
4419          // indirectly through its super class.
4420          if (lhsID->ClassImplementsProtocol(*I, true)) {
4421            match = true;
4422            break;
4423          }
4424        }
4425        if (!match)
4426          return false;
4427      }
4428      return true;
4429    }
4430    // Both the right and left sides have qualifiers.
4431    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
4432         E = lhsOPT->qual_end(); I != E; ++I) {
4433      ObjCProtocolDecl *lhsProto = *I;
4434      bool match = false;
4435
4436      // when comparing an id<P> on lhs with a static type on rhs,
4437      // see if static class implements all of id's protocols, directly or
4438      // through its super class and categories.
4439      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
4440           E = rhsQID->qual_end(); J != E; ++J) {
4441        ObjCProtocolDecl *rhsProto = *J;
4442        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
4443            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
4444          match = true;
4445          break;
4446        }
4447      }
4448      if (!match)
4449        return false;
4450    }
4451    return true;
4452  }
4453  return false;
4454}
4455
4456/// canAssignObjCInterfaces - Return true if the two interface types are
4457/// compatible for assignment from RHS to LHS.  This handles validation of any
4458/// protocol qualifiers on the LHS or RHS.
4459///
4460bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
4461                                         const ObjCObjectPointerType *RHSOPT) {
4462  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4463  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4464
4465  // If either type represents the built-in 'id' or 'Class' types, return true.
4466  if (LHS->isObjCUnqualifiedIdOrClass() ||
4467      RHS->isObjCUnqualifiedIdOrClass())
4468    return true;
4469
4470  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
4471    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4472                                             QualType(RHSOPT,0),
4473                                             false);
4474
4475  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
4476    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
4477                                                QualType(RHSOPT,0));
4478
4479  // If we have 2 user-defined types, fall into that path.
4480  if (LHS->getInterface() && RHS->getInterface())
4481    return canAssignObjCInterfaces(LHS, RHS);
4482
4483  return false;
4484}
4485
4486/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
4487/// for providing type-safty for objective-c pointers used to pass/return
4488/// arguments in block literals. When passed as arguments, passing 'A*' where
4489/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
4490/// not OK. For the return type, the opposite is not OK.
4491bool ASTContext::canAssignObjCInterfacesInBlockPointer(
4492                                         const ObjCObjectPointerType *LHSOPT,
4493                                         const ObjCObjectPointerType *RHSOPT) {
4494  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
4495    return true;
4496
4497  if (LHSOPT->isObjCBuiltinType()) {
4498    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
4499  }
4500
4501  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
4502    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
4503                                             QualType(RHSOPT,0),
4504                                             false);
4505
4506  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
4507  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
4508  if (LHS && RHS)  { // We have 2 user-defined types.
4509    if (LHS != RHS) {
4510      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
4511        return false;
4512      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
4513        return true;
4514    }
4515    else
4516      return true;
4517  }
4518  return false;
4519}
4520
4521/// getIntersectionOfProtocols - This routine finds the intersection of set
4522/// of protocols inherited from two distinct objective-c pointer objects.
4523/// It is used to build composite qualifier list of the composite type of
4524/// the conditional expression involving two objective-c pointer objects.
4525static
4526void getIntersectionOfProtocols(ASTContext &Context,
4527                                const ObjCObjectPointerType *LHSOPT,
4528                                const ObjCObjectPointerType *RHSOPT,
4529      llvm::SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
4530
4531  const ObjCObjectType* LHS = LHSOPT->getObjectType();
4532  const ObjCObjectType* RHS = RHSOPT->getObjectType();
4533  assert(LHS->getInterface() && "LHS must have an interface base");
4534  assert(RHS->getInterface() && "RHS must have an interface base");
4535
4536  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
4537  unsigned LHSNumProtocols = LHS->getNumProtocols();
4538  if (LHSNumProtocols > 0)
4539    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
4540  else {
4541    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
4542    Context.CollectInheritedProtocols(LHS->getInterface(),
4543                                      LHSInheritedProtocols);
4544    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
4545                                LHSInheritedProtocols.end());
4546  }
4547
4548  unsigned RHSNumProtocols = RHS->getNumProtocols();
4549  if (RHSNumProtocols > 0) {
4550    ObjCProtocolDecl **RHSProtocols =
4551      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
4552    for (unsigned i = 0; i < RHSNumProtocols; ++i)
4553      if (InheritedProtocolSet.count(RHSProtocols[i]))
4554        IntersectionOfProtocols.push_back(RHSProtocols[i]);
4555  }
4556  else {
4557    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
4558    Context.CollectInheritedProtocols(RHS->getInterface(),
4559                                      RHSInheritedProtocols);
4560    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
4561         RHSInheritedProtocols.begin(),
4562         E = RHSInheritedProtocols.end(); I != E; ++I)
4563      if (InheritedProtocolSet.count((*I)))
4564        IntersectionOfProtocols.push_back((*I));
4565  }
4566}
4567
4568/// areCommonBaseCompatible - Returns common base class of the two classes if
4569/// one found. Note that this is O'2 algorithm. But it will be called as the
4570/// last type comparison in a ?-exp of ObjC pointer types before a
4571/// warning is issued. So, its invokation is extremely rare.
4572QualType ASTContext::areCommonBaseCompatible(
4573                                          const ObjCObjectPointerType *Lptr,
4574                                          const ObjCObjectPointerType *Rptr) {
4575  const ObjCObjectType *LHS = Lptr->getObjectType();
4576  const ObjCObjectType *RHS = Rptr->getObjectType();
4577  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
4578  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
4579  if (!LDecl || !RDecl)
4580    return QualType();
4581
4582  while ((LDecl = LDecl->getSuperClass())) {
4583    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
4584    if (canAssignObjCInterfaces(LHS, RHS)) {
4585      llvm::SmallVector<ObjCProtocolDecl *, 8> Protocols;
4586      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
4587
4588      QualType Result = QualType(LHS, 0);
4589      if (!Protocols.empty())
4590        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
4591      Result = getObjCObjectPointerType(Result);
4592      return Result;
4593    }
4594  }
4595
4596  return QualType();
4597}
4598
4599bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
4600                                         const ObjCObjectType *RHS) {
4601  assert(LHS->getInterface() && "LHS is not an interface type");
4602  assert(RHS->getInterface() && "RHS is not an interface type");
4603
4604  // Verify that the base decls are compatible: the RHS must be a subclass of
4605  // the LHS.
4606  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
4607    return false;
4608
4609  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
4610  // protocol qualified at all, then we are good.
4611  if (LHS->getNumProtocols() == 0)
4612    return true;
4613
4614  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't, then it
4615  // isn't a superset.
4616  if (RHS->getNumProtocols() == 0)
4617    return true;  // FIXME: should return false!
4618
4619  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
4620                                     LHSPE = LHS->qual_end();
4621       LHSPI != LHSPE; LHSPI++) {
4622    bool RHSImplementsProtocol = false;
4623
4624    // If the RHS doesn't implement the protocol on the left, the types
4625    // are incompatible.
4626    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
4627                                       RHSPE = RHS->qual_end();
4628         RHSPI != RHSPE; RHSPI++) {
4629      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
4630        RHSImplementsProtocol = true;
4631        break;
4632      }
4633    }
4634    // FIXME: For better diagnostics, consider passing back the protocol name.
4635    if (!RHSImplementsProtocol)
4636      return false;
4637  }
4638  // The RHS implements all protocols listed on the LHS.
4639  return true;
4640}
4641
4642bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
4643  // get the "pointed to" types
4644  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
4645  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
4646
4647  if (!LHSOPT || !RHSOPT)
4648    return false;
4649
4650  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
4651         canAssignObjCInterfaces(RHSOPT, LHSOPT);
4652}
4653
4654bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
4655  return canAssignObjCInterfaces(
4656                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
4657                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
4658}
4659
4660/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
4661/// both shall have the identically qualified version of a compatible type.
4662/// C99 6.2.7p1: Two types have compatible types if their types are the
4663/// same. See 6.7.[2,3,5] for additional rules.
4664bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
4665                                    bool CompareUnqualified) {
4666  if (getLangOptions().CPlusPlus)
4667    return hasSameType(LHS, RHS);
4668
4669  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
4670}
4671
4672bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
4673  return !mergeTypes(LHS, RHS, true).isNull();
4674}
4675
4676QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
4677                                        bool OfBlockPointer,
4678                                        bool Unqualified) {
4679  const FunctionType *lbase = lhs->getAs<FunctionType>();
4680  const FunctionType *rbase = rhs->getAs<FunctionType>();
4681  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
4682  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
4683  bool allLTypes = true;
4684  bool allRTypes = true;
4685
4686  // Check return type
4687  QualType retType;
4688  if (OfBlockPointer)
4689    retType = mergeTypes(rbase->getResultType(), lbase->getResultType(), true,
4690                         Unqualified);
4691  else
4692   retType = mergeTypes(lbase->getResultType(), rbase->getResultType(),
4693                        false, Unqualified);
4694  if (retType.isNull()) return QualType();
4695
4696  if (Unqualified)
4697    retType = retType.getUnqualifiedType();
4698
4699  CanQualType LRetType = getCanonicalType(lbase->getResultType());
4700  CanQualType RRetType = getCanonicalType(rbase->getResultType());
4701  if (Unqualified) {
4702    LRetType = LRetType.getUnqualifiedType();
4703    RRetType = RRetType.getUnqualifiedType();
4704  }
4705
4706  if (getCanonicalType(retType) != LRetType)
4707    allLTypes = false;
4708  if (getCanonicalType(retType) != RRetType)
4709    allRTypes = false;
4710  // FIXME: double check this
4711  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
4712  //                           rbase->getRegParmAttr() != 0 &&
4713  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
4714  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
4715  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
4716  unsigned RegParm = lbaseInfo.getRegParm() == 0 ? rbaseInfo.getRegParm() :
4717      lbaseInfo.getRegParm();
4718  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
4719  if (NoReturn != lbaseInfo.getNoReturn() ||
4720      RegParm != lbaseInfo.getRegParm())
4721    allLTypes = false;
4722  if (NoReturn != rbaseInfo.getNoReturn() ||
4723      RegParm != rbaseInfo.getRegParm())
4724    allRTypes = false;
4725  CallingConv lcc = lbaseInfo.getCC();
4726  CallingConv rcc = rbaseInfo.getCC();
4727  // Compatible functions must have compatible calling conventions
4728  if (!isSameCallConv(lcc, rcc))
4729    return QualType();
4730
4731  if (lproto && rproto) { // two C99 style function prototypes
4732    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
4733           "C++ shouldn't be here");
4734    unsigned lproto_nargs = lproto->getNumArgs();
4735    unsigned rproto_nargs = rproto->getNumArgs();
4736
4737    // Compatible functions must have the same number of arguments
4738    if (lproto_nargs != rproto_nargs)
4739      return QualType();
4740
4741    // Variadic and non-variadic functions aren't compatible
4742    if (lproto->isVariadic() != rproto->isVariadic())
4743      return QualType();
4744
4745    if (lproto->getTypeQuals() != rproto->getTypeQuals())
4746      return QualType();
4747
4748    // Check argument compatibility
4749    llvm::SmallVector<QualType, 10> types;
4750    for (unsigned i = 0; i < lproto_nargs; i++) {
4751      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
4752      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
4753      QualType argtype = mergeTypes(largtype, rargtype, OfBlockPointer,
4754                                    Unqualified);
4755      if (argtype.isNull()) return QualType();
4756
4757      if (Unqualified)
4758        argtype = argtype.getUnqualifiedType();
4759
4760      types.push_back(argtype);
4761      if (Unqualified) {
4762        largtype = largtype.getUnqualifiedType();
4763        rargtype = rargtype.getUnqualifiedType();
4764      }
4765
4766      if (getCanonicalType(argtype) != getCanonicalType(largtype))
4767        allLTypes = false;
4768      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
4769        allRTypes = false;
4770    }
4771    if (allLTypes) return lhs;
4772    if (allRTypes) return rhs;
4773    return getFunctionType(retType, types.begin(), types.size(),
4774                           lproto->isVariadic(), lproto->getTypeQuals(),
4775                           false, false, 0, 0,
4776                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4777  }
4778
4779  if (lproto) allRTypes = false;
4780  if (rproto) allLTypes = false;
4781
4782  const FunctionProtoType *proto = lproto ? lproto : rproto;
4783  if (proto) {
4784    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
4785    if (proto->isVariadic()) return QualType();
4786    // Check that the types are compatible with the types that
4787    // would result from default argument promotions (C99 6.7.5.3p15).
4788    // The only types actually affected are promotable integer
4789    // types and floats, which would be passed as a different
4790    // type depending on whether the prototype is visible.
4791    unsigned proto_nargs = proto->getNumArgs();
4792    for (unsigned i = 0; i < proto_nargs; ++i) {
4793      QualType argTy = proto->getArgType(i);
4794
4795      // Look at the promotion type of enum types, since that is the type used
4796      // to pass enum values.
4797      if (const EnumType *Enum = argTy->getAs<EnumType>())
4798        argTy = Enum->getDecl()->getPromotionType();
4799
4800      if (argTy->isPromotableIntegerType() ||
4801          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
4802        return QualType();
4803    }
4804
4805    if (allLTypes) return lhs;
4806    if (allRTypes) return rhs;
4807    return getFunctionType(retType, proto->arg_type_begin(),
4808                           proto->getNumArgs(), proto->isVariadic(),
4809                           proto->getTypeQuals(),
4810                           false, false, 0, 0,
4811                           FunctionType::ExtInfo(NoReturn, RegParm, lcc));
4812  }
4813
4814  if (allLTypes) return lhs;
4815  if (allRTypes) return rhs;
4816  FunctionType::ExtInfo Info(NoReturn, RegParm, lcc);
4817  return getFunctionNoProtoType(retType, Info);
4818}
4819
4820QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
4821                                bool OfBlockPointer,
4822                                bool Unqualified) {
4823  // C++ [expr]: If an expression initially has the type "reference to T", the
4824  // type is adjusted to "T" prior to any further analysis, the expression
4825  // designates the object or function denoted by the reference, and the
4826  // expression is an lvalue unless the reference is an rvalue reference and
4827  // the expression is a function call (possibly inside parentheses).
4828  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
4829  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
4830
4831  if (Unqualified) {
4832    LHS = LHS.getUnqualifiedType();
4833    RHS = RHS.getUnqualifiedType();
4834  }
4835
4836  QualType LHSCan = getCanonicalType(LHS),
4837           RHSCan = getCanonicalType(RHS);
4838
4839  // If two types are identical, they are compatible.
4840  if (LHSCan == RHSCan)
4841    return LHS;
4842
4843  // If the qualifiers are different, the types aren't compatible... mostly.
4844  Qualifiers LQuals = LHSCan.getLocalQualifiers();
4845  Qualifiers RQuals = RHSCan.getLocalQualifiers();
4846  if (LQuals != RQuals) {
4847    // If any of these qualifiers are different, we have a type
4848    // mismatch.
4849    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
4850        LQuals.getAddressSpace() != RQuals.getAddressSpace())
4851      return QualType();
4852
4853    // Exactly one GC qualifier difference is allowed: __strong is
4854    // okay if the other type has no GC qualifier but is an Objective
4855    // C object pointer (i.e. implicitly strong by default).  We fix
4856    // this by pretending that the unqualified type was actually
4857    // qualified __strong.
4858    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
4859    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
4860    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
4861
4862    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
4863      return QualType();
4864
4865    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
4866      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
4867    }
4868    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
4869      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
4870    }
4871    return QualType();
4872  }
4873
4874  // Okay, qualifiers are equal.
4875
4876  Type::TypeClass LHSClass = LHSCan->getTypeClass();
4877  Type::TypeClass RHSClass = RHSCan->getTypeClass();
4878
4879  // We want to consider the two function types to be the same for these
4880  // comparisons, just force one to the other.
4881  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
4882  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
4883
4884  // Same as above for arrays
4885  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
4886    LHSClass = Type::ConstantArray;
4887  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
4888    RHSClass = Type::ConstantArray;
4889
4890  // ObjCInterfaces are just specialized ObjCObjects.
4891  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
4892  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
4893
4894  // Canonicalize ExtVector -> Vector.
4895  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
4896  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
4897
4898  // If the canonical type classes don't match.
4899  if (LHSClass != RHSClass) {
4900    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
4901    // a signed integer type, or an unsigned integer type.
4902    // Compatibility is based on the underlying type, not the promotion
4903    // type.
4904    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
4905      if (ETy->getDecl()->getIntegerType() == RHSCan.getUnqualifiedType())
4906        return RHS;
4907    }
4908    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
4909      if (ETy->getDecl()->getIntegerType() == LHSCan.getUnqualifiedType())
4910        return LHS;
4911    }
4912
4913    return QualType();
4914  }
4915
4916  // The canonical type classes match.
4917  switch (LHSClass) {
4918#define TYPE(Class, Base)
4919#define ABSTRACT_TYPE(Class, Base)
4920#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
4921#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
4922#define DEPENDENT_TYPE(Class, Base) case Type::Class:
4923#include "clang/AST/TypeNodes.def"
4924    assert(false && "Non-canonical and dependent types shouldn't get here");
4925    return QualType();
4926
4927  case Type::LValueReference:
4928  case Type::RValueReference:
4929  case Type::MemberPointer:
4930    assert(false && "C++ should never be in mergeTypes");
4931    return QualType();
4932
4933  case Type::ObjCInterface:
4934  case Type::IncompleteArray:
4935  case Type::VariableArray:
4936  case Type::FunctionProto:
4937  case Type::ExtVector:
4938    assert(false && "Types are eliminated above");
4939    return QualType();
4940
4941  case Type::Pointer:
4942  {
4943    // Merge two pointer types, while trying to preserve typedef info
4944    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
4945    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
4946    if (Unqualified) {
4947      LHSPointee = LHSPointee.getUnqualifiedType();
4948      RHSPointee = RHSPointee.getUnqualifiedType();
4949    }
4950    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
4951                                     Unqualified);
4952    if (ResultType.isNull()) return QualType();
4953    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
4954      return LHS;
4955    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
4956      return RHS;
4957    return getPointerType(ResultType);
4958  }
4959  case Type::BlockPointer:
4960  {
4961    // Merge two block pointer types, while trying to preserve typedef info
4962    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
4963    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
4964    if (Unqualified) {
4965      LHSPointee = LHSPointee.getUnqualifiedType();
4966      RHSPointee = RHSPointee.getUnqualifiedType();
4967    }
4968    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
4969                                     Unqualified);
4970    if (ResultType.isNull()) return QualType();
4971    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
4972      return LHS;
4973    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
4974      return RHS;
4975    return getBlockPointerType(ResultType);
4976  }
4977  case Type::ConstantArray:
4978  {
4979    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
4980    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
4981    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
4982      return QualType();
4983
4984    QualType LHSElem = getAsArrayType(LHS)->getElementType();
4985    QualType RHSElem = getAsArrayType(RHS)->getElementType();
4986    if (Unqualified) {
4987      LHSElem = LHSElem.getUnqualifiedType();
4988      RHSElem = RHSElem.getUnqualifiedType();
4989    }
4990
4991    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
4992    if (ResultType.isNull()) return QualType();
4993    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
4994      return LHS;
4995    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
4996      return RHS;
4997    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
4998                                          ArrayType::ArraySizeModifier(), 0);
4999    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
5000                                          ArrayType::ArraySizeModifier(), 0);
5001    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
5002    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
5003    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
5004      return LHS;
5005    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
5006      return RHS;
5007    if (LVAT) {
5008      // FIXME: This isn't correct! But tricky to implement because
5009      // the array's size has to be the size of LHS, but the type
5010      // has to be different.
5011      return LHS;
5012    }
5013    if (RVAT) {
5014      // FIXME: This isn't correct! But tricky to implement because
5015      // the array's size has to be the size of RHS, but the type
5016      // has to be different.
5017      return RHS;
5018    }
5019    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
5020    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
5021    return getIncompleteArrayType(ResultType,
5022                                  ArrayType::ArraySizeModifier(), 0);
5023  }
5024  case Type::FunctionNoProto:
5025    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
5026  case Type::Record:
5027  case Type::Enum:
5028    return QualType();
5029  case Type::Builtin:
5030    // Only exactly equal builtin types are compatible, which is tested above.
5031    return QualType();
5032  case Type::Complex:
5033    // Distinct complex types are incompatible.
5034    return QualType();
5035  case Type::Vector:
5036    // FIXME: The merged type should be an ExtVector!
5037    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
5038                             RHSCan->getAs<VectorType>()))
5039      return LHS;
5040    return QualType();
5041  case Type::ObjCObject: {
5042    // Check if the types are assignment compatible.
5043    // FIXME: This should be type compatibility, e.g. whether
5044    // "LHS x; RHS x;" at global scope is legal.
5045    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
5046    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
5047    if (canAssignObjCInterfaces(LHSIface, RHSIface))
5048      return LHS;
5049
5050    return QualType();
5051  }
5052  case Type::ObjCObjectPointer: {
5053    if (OfBlockPointer) {
5054      if (canAssignObjCInterfacesInBlockPointer(
5055                                          LHS->getAs<ObjCObjectPointerType>(),
5056                                          RHS->getAs<ObjCObjectPointerType>()))
5057      return LHS;
5058      return QualType();
5059    }
5060    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
5061                                RHS->getAs<ObjCObjectPointerType>()))
5062      return LHS;
5063
5064    return QualType();
5065    }
5066  }
5067
5068  return QualType();
5069}
5070
5071/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
5072/// 'RHS' attributes and returns the merged version; including for function
5073/// return types.
5074QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
5075  QualType LHSCan = getCanonicalType(LHS),
5076  RHSCan = getCanonicalType(RHS);
5077  // If two types are identical, they are compatible.
5078  if (LHSCan == RHSCan)
5079    return LHS;
5080  if (RHSCan->isFunctionType()) {
5081    if (!LHSCan->isFunctionType())
5082      return QualType();
5083    QualType OldReturnType =
5084      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
5085    QualType NewReturnType =
5086      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
5087    QualType ResReturnType =
5088      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
5089    if (ResReturnType.isNull())
5090      return QualType();
5091    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
5092      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
5093      // In either case, use OldReturnType to build the new function type.
5094      const FunctionType *F = LHS->getAs<FunctionType>();
5095      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
5096        FunctionType::ExtInfo Info = getFunctionExtInfo(LHS);
5097        QualType ResultType
5098          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
5099                                  FPT->getNumArgs(), FPT->isVariadic(),
5100                                  FPT->getTypeQuals(),
5101                                  FPT->hasExceptionSpec(),
5102                                  FPT->hasAnyExceptionSpec(),
5103                                  FPT->getNumExceptions(),
5104                                  FPT->exception_begin(),
5105                                  Info);
5106        return ResultType;
5107      }
5108    }
5109    return QualType();
5110  }
5111
5112  // If the qualifiers are different, the types can still be merged.
5113  Qualifiers LQuals = LHSCan.getLocalQualifiers();
5114  Qualifiers RQuals = RHSCan.getLocalQualifiers();
5115  if (LQuals != RQuals) {
5116    // If any of these qualifiers are different, we have a type mismatch.
5117    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
5118        LQuals.getAddressSpace() != RQuals.getAddressSpace())
5119      return QualType();
5120
5121    // Exactly one GC qualifier difference is allowed: __strong is
5122    // okay if the other type has no GC qualifier but is an Objective
5123    // C object pointer (i.e. implicitly strong by default).  We fix
5124    // this by pretending that the unqualified type was actually
5125    // qualified __strong.
5126    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
5127    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
5128    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
5129
5130    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
5131      return QualType();
5132
5133    if (GC_L == Qualifiers::Strong)
5134      return LHS;
5135    if (GC_R == Qualifiers::Strong)
5136      return RHS;
5137    return QualType();
5138  }
5139
5140  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
5141    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5142    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
5143    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
5144    if (ResQT == LHSBaseQT)
5145      return LHS;
5146    if (ResQT == RHSBaseQT)
5147      return RHS;
5148  }
5149  return QualType();
5150}
5151
5152//===----------------------------------------------------------------------===//
5153//                         Integer Predicates
5154//===----------------------------------------------------------------------===//
5155
5156unsigned ASTContext::getIntWidth(QualType T) {
5157  if (EnumType *ET = dyn_cast<EnumType>(T))
5158    T = ET->getDecl()->getIntegerType();
5159  if (T->isBooleanType())
5160    return 1;
5161  // For builtin types, just use the standard type sizing method
5162  return (unsigned)getTypeSize(T);
5163}
5164
5165QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
5166  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
5167
5168  // Turn <4 x signed int> -> <4 x unsigned int>
5169  if (const VectorType *VTy = T->getAs<VectorType>())
5170    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
5171             VTy->getNumElements(), VTy->getAltiVecSpecific());
5172
5173  // For enums, we return the unsigned version of the base type.
5174  if (const EnumType *ETy = T->getAs<EnumType>())
5175    T = ETy->getDecl()->getIntegerType();
5176
5177  const BuiltinType *BTy = T->getAs<BuiltinType>();
5178  assert(BTy && "Unexpected signed integer type");
5179  switch (BTy->getKind()) {
5180  case BuiltinType::Char_S:
5181  case BuiltinType::SChar:
5182    return UnsignedCharTy;
5183  case BuiltinType::Short:
5184    return UnsignedShortTy;
5185  case BuiltinType::Int:
5186    return UnsignedIntTy;
5187  case BuiltinType::Long:
5188    return UnsignedLongTy;
5189  case BuiltinType::LongLong:
5190    return UnsignedLongLongTy;
5191  case BuiltinType::Int128:
5192    return UnsignedInt128Ty;
5193  default:
5194    assert(0 && "Unexpected signed integer type");
5195    return QualType();
5196  }
5197}
5198
5199ExternalASTSource::~ExternalASTSource() { }
5200
5201void ExternalASTSource::PrintStats() { }
5202
5203
5204//===----------------------------------------------------------------------===//
5205//                          Builtin Type Computation
5206//===----------------------------------------------------------------------===//
5207
5208/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
5209/// pointer over the consumed characters.  This returns the resultant type.  If
5210/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
5211/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
5212/// a vector of "i*".
5213///
5214/// RequiresICE is filled in on return to indicate whether the value is required
5215/// to be an Integer Constant Expression.
5216static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
5217                                  ASTContext::GetBuiltinTypeError &Error,
5218                                  bool &RequiresICE,
5219                                  bool AllowTypeModifiers) {
5220  // Modifiers.
5221  int HowLong = 0;
5222  bool Signed = false, Unsigned = false;
5223  RequiresICE = false;
5224
5225  // Read the prefixed modifiers first.
5226  bool Done = false;
5227  while (!Done) {
5228    switch (*Str++) {
5229    default: Done = true; --Str; break;
5230    case 'I':
5231      RequiresICE = true;
5232      break;
5233    case 'S':
5234      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
5235      assert(!Signed && "Can't use 'S' modifier multiple times!");
5236      Signed = true;
5237      break;
5238    case 'U':
5239      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
5240      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
5241      Unsigned = true;
5242      break;
5243    case 'L':
5244      assert(HowLong <= 2 && "Can't have LLLL modifier");
5245      ++HowLong;
5246      break;
5247    }
5248  }
5249
5250  QualType Type;
5251
5252  // Read the base type.
5253  switch (*Str++) {
5254  default: assert(0 && "Unknown builtin type letter!");
5255  case 'v':
5256    assert(HowLong == 0 && !Signed && !Unsigned &&
5257           "Bad modifiers used with 'v'!");
5258    Type = Context.VoidTy;
5259    break;
5260  case 'f':
5261    assert(HowLong == 0 && !Signed && !Unsigned &&
5262           "Bad modifiers used with 'f'!");
5263    Type = Context.FloatTy;
5264    break;
5265  case 'd':
5266    assert(HowLong < 2 && !Signed && !Unsigned &&
5267           "Bad modifiers used with 'd'!");
5268    if (HowLong)
5269      Type = Context.LongDoubleTy;
5270    else
5271      Type = Context.DoubleTy;
5272    break;
5273  case 's':
5274    assert(HowLong == 0 && "Bad modifiers used with 's'!");
5275    if (Unsigned)
5276      Type = Context.UnsignedShortTy;
5277    else
5278      Type = Context.ShortTy;
5279    break;
5280  case 'i':
5281    if (HowLong == 3)
5282      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
5283    else if (HowLong == 2)
5284      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
5285    else if (HowLong == 1)
5286      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
5287    else
5288      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
5289    break;
5290  case 'c':
5291    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
5292    if (Signed)
5293      Type = Context.SignedCharTy;
5294    else if (Unsigned)
5295      Type = Context.UnsignedCharTy;
5296    else
5297      Type = Context.CharTy;
5298    break;
5299  case 'b': // boolean
5300    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
5301    Type = Context.BoolTy;
5302    break;
5303  case 'z':  // size_t.
5304    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
5305    Type = Context.getSizeType();
5306    break;
5307  case 'F':
5308    Type = Context.getCFConstantStringType();
5309    break;
5310  case 'a':
5311    Type = Context.getBuiltinVaListType();
5312    assert(!Type.isNull() && "builtin va list type not initialized!");
5313    break;
5314  case 'A':
5315    // This is a "reference" to a va_list; however, what exactly
5316    // this means depends on how va_list is defined. There are two
5317    // different kinds of va_list: ones passed by value, and ones
5318    // passed by reference.  An example of a by-value va_list is
5319    // x86, where va_list is a char*. An example of by-ref va_list
5320    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
5321    // we want this argument to be a char*&; for x86-64, we want
5322    // it to be a __va_list_tag*.
5323    Type = Context.getBuiltinVaListType();
5324    assert(!Type.isNull() && "builtin va list type not initialized!");
5325    if (Type->isArrayType())
5326      Type = Context.getArrayDecayedType(Type);
5327    else
5328      Type = Context.getLValueReferenceType(Type);
5329    break;
5330  case 'V': {
5331    char *End;
5332    unsigned NumElements = strtoul(Str, &End, 10);
5333    assert(End != Str && "Missing vector size");
5334    Str = End;
5335
5336    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
5337                                             RequiresICE, false);
5338    assert(!RequiresICE && "Can't require vector ICE");
5339
5340    // TODO: No way to make AltiVec vectors in builtins yet.
5341    Type = Context.getVectorType(ElementType, NumElements,
5342                                 VectorType::NotAltiVec);
5343    break;
5344  }
5345  case 'X': {
5346    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
5347                                             false);
5348    assert(!RequiresICE && "Can't require complex ICE");
5349    Type = Context.getComplexType(ElementType);
5350    break;
5351  }
5352  case 'P':
5353    Type = Context.getFILEType();
5354    if (Type.isNull()) {
5355      Error = ASTContext::GE_Missing_stdio;
5356      return QualType();
5357    }
5358    break;
5359  case 'J':
5360    if (Signed)
5361      Type = Context.getsigjmp_bufType();
5362    else
5363      Type = Context.getjmp_bufType();
5364
5365    if (Type.isNull()) {
5366      Error = ASTContext::GE_Missing_setjmp;
5367      return QualType();
5368    }
5369    break;
5370  }
5371
5372  // If there are modifiers and if we're allowed to parse them, go for it.
5373  Done = !AllowTypeModifiers;
5374  while (!Done) {
5375    switch (char c = *Str++) {
5376    default: Done = true; --Str; break;
5377    case '*':
5378    case '&': {
5379      // Both pointers and references can have their pointee types
5380      // qualified with an address space.
5381      char *End;
5382      unsigned AddrSpace = strtoul(Str, &End, 10);
5383      if (End != Str && AddrSpace != 0) {
5384        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
5385        Str = End;
5386      }
5387      if (c == '*')
5388        Type = Context.getPointerType(Type);
5389      else
5390        Type = Context.getLValueReferenceType(Type);
5391      break;
5392    }
5393    // FIXME: There's no way to have a built-in with an rvalue ref arg.
5394    case 'C':
5395      Type = Type.withConst();
5396      break;
5397    case 'D':
5398      Type = Context.getVolatileType(Type);
5399      break;
5400    }
5401  }
5402
5403  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
5404         "Integer constant 'I' type must be an integer");
5405
5406  return Type;
5407}
5408
5409/// GetBuiltinType - Return the type for the specified builtin.
5410QualType ASTContext::GetBuiltinType(unsigned Id,
5411                                    GetBuiltinTypeError &Error,
5412                                    unsigned *IntegerConstantArgs) {
5413  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
5414
5415  llvm::SmallVector<QualType, 8> ArgTypes;
5416
5417  bool RequiresICE = false;
5418  Error = GE_None;
5419  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
5420                                       RequiresICE, true);
5421  if (Error != GE_None)
5422    return QualType();
5423
5424  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
5425
5426  while (TypeStr[0] && TypeStr[0] != '.') {
5427    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
5428    if (Error != GE_None)
5429      return QualType();
5430
5431    // If this argument is required to be an IntegerConstantExpression and the
5432    // caller cares, fill in the bitmask we return.
5433    if (RequiresICE && IntegerConstantArgs)
5434      *IntegerConstantArgs |= 1 << ArgTypes.size();
5435
5436    // Do array -> pointer decay.  The builtin should use the decayed type.
5437    if (Ty->isArrayType())
5438      Ty = getArrayDecayedType(Ty);
5439
5440    ArgTypes.push_back(Ty);
5441  }
5442
5443  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
5444         "'.' should only occur at end of builtin type list!");
5445
5446  // handle untyped/variadic arguments "T c99Style();" or "T cppStyle(...);".
5447  if (ArgTypes.size() == 0 && TypeStr[0] == '.')
5448    return getFunctionNoProtoType(ResType);
5449
5450  // FIXME: Should we create noreturn types?
5451  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(),
5452                         TypeStr[0] == '.', 0, false, false, 0, 0,
5453                         FunctionType::ExtInfo());
5454}
5455
5456QualType
5457ASTContext::UsualArithmeticConversionsType(QualType lhs, QualType rhs) {
5458  // Perform the usual unary conversions. We do this early so that
5459  // integral promotions to "int" can allow us to exit early, in the
5460  // lhs == rhs check. Also, for conversion purposes, we ignore any
5461  // qualifiers.  For example, "const float" and "float" are
5462  // equivalent.
5463  if (lhs->isPromotableIntegerType())
5464    lhs = getPromotedIntegerType(lhs);
5465  else
5466    lhs = lhs.getUnqualifiedType();
5467  if (rhs->isPromotableIntegerType())
5468    rhs = getPromotedIntegerType(rhs);
5469  else
5470    rhs = rhs.getUnqualifiedType();
5471
5472  // If both types are identical, no conversion is needed.
5473  if (lhs == rhs)
5474    return lhs;
5475
5476  // If either side is a non-arithmetic type (e.g. a pointer), we are done.
5477  // The caller can deal with this (e.g. pointer + int).
5478  if (!lhs->isArithmeticType() || !rhs->isArithmeticType())
5479    return lhs;
5480
5481  // At this point, we have two different arithmetic types.
5482
5483  // Handle complex types first (C99 6.3.1.8p1).
5484  if (lhs->isComplexType() || rhs->isComplexType()) {
5485    // if we have an integer operand, the result is the complex type.
5486    if (rhs->isIntegerType() || rhs->isComplexIntegerType()) {
5487      // convert the rhs to the lhs complex type.
5488      return lhs;
5489    }
5490    if (lhs->isIntegerType() || lhs->isComplexIntegerType()) {
5491      // convert the lhs to the rhs complex type.
5492      return rhs;
5493    }
5494    // This handles complex/complex, complex/float, or float/complex.
5495    // When both operands are complex, the shorter operand is converted to the
5496    // type of the longer, and that is the type of the result. This corresponds
5497    // to what is done when combining two real floating-point operands.
5498    // The fun begins when size promotion occur across type domains.
5499    // From H&S 6.3.4: When one operand is complex and the other is a real
5500    // floating-point type, the less precise type is converted, within it's
5501    // real or complex domain, to the precision of the other type. For example,
5502    // when combining a "long double" with a "double _Complex", the
5503    // "double _Complex" is promoted to "long double _Complex".
5504    int result = getFloatingTypeOrder(lhs, rhs);
5505
5506    if (result > 0) { // The left side is bigger, convert rhs.
5507      rhs = getFloatingTypeOfSizeWithinDomain(lhs, rhs);
5508    } else if (result < 0) { // The right side is bigger, convert lhs.
5509      lhs = getFloatingTypeOfSizeWithinDomain(rhs, lhs);
5510    }
5511    // At this point, lhs and rhs have the same rank/size. Now, make sure the
5512    // domains match. This is a requirement for our implementation, C99
5513    // does not require this promotion.
5514    if (lhs != rhs) { // Domains don't match, we have complex/float mix.
5515      if (lhs->isRealFloatingType()) { // handle "double, _Complex double".
5516        return rhs;
5517      } else { // handle "_Complex double, double".
5518        return lhs;
5519      }
5520    }
5521    return lhs; // The domain/size match exactly.
5522  }
5523  // Now handle "real" floating types (i.e. float, double, long double).
5524  if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) {
5525    // if we have an integer operand, the result is the real floating type.
5526    if (rhs->isIntegerType()) {
5527      // convert rhs to the lhs floating point type.
5528      return lhs;
5529    }
5530    if (rhs->isComplexIntegerType()) {
5531      // convert rhs to the complex floating point type.
5532      return getComplexType(lhs);
5533    }
5534    if (lhs->isIntegerType()) {
5535      // convert lhs to the rhs floating point type.
5536      return rhs;
5537    }
5538    if (lhs->isComplexIntegerType()) {
5539      // convert lhs to the complex floating point type.
5540      return getComplexType(rhs);
5541    }
5542    // We have two real floating types, float/complex combos were handled above.
5543    // Convert the smaller operand to the bigger result.
5544    int result = getFloatingTypeOrder(lhs, rhs);
5545    if (result > 0) // convert the rhs
5546      return lhs;
5547    assert(result < 0 && "illegal float comparison");
5548    return rhs;   // convert the lhs
5549  }
5550  if (lhs->isComplexIntegerType() || rhs->isComplexIntegerType()) {
5551    // Handle GCC complex int extension.
5552    const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType();
5553    const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType();
5554
5555    if (lhsComplexInt && rhsComplexInt) {
5556      if (getIntegerTypeOrder(lhsComplexInt->getElementType(),
5557                              rhsComplexInt->getElementType()) >= 0)
5558        return lhs; // convert the rhs
5559      return rhs;
5560    } else if (lhsComplexInt && rhs->isIntegerType()) {
5561      // convert the rhs to the lhs complex type.
5562      return lhs;
5563    } else if (rhsComplexInt && lhs->isIntegerType()) {
5564      // convert the lhs to the rhs complex type.
5565      return rhs;
5566    }
5567  }
5568  // Finally, we have two differing integer types.
5569  // The rules for this case are in C99 6.3.1.8
5570  int compare = getIntegerTypeOrder(lhs, rhs);
5571  bool lhsSigned = lhs->hasSignedIntegerRepresentation(),
5572       rhsSigned = rhs->hasSignedIntegerRepresentation();
5573  QualType destType;
5574  if (lhsSigned == rhsSigned) {
5575    // Same signedness; use the higher-ranked type
5576    destType = compare >= 0 ? lhs : rhs;
5577  } else if (compare != (lhsSigned ? 1 : -1)) {
5578    // The unsigned type has greater than or equal rank to the
5579    // signed type, so use the unsigned type
5580    destType = lhsSigned ? rhs : lhs;
5581  } else if (getIntWidth(lhs) != getIntWidth(rhs)) {
5582    // The two types are different widths; if we are here, that
5583    // means the signed type is larger than the unsigned type, so
5584    // use the signed type.
5585    destType = lhsSigned ? lhs : rhs;
5586  } else {
5587    // The signed type is higher-ranked than the unsigned type,
5588    // but isn't actually any bigger (like unsigned int and long
5589    // on most 32-bit systems).  Use the unsigned type corresponding
5590    // to the signed type.
5591    destType = getCorrespondingUnsignedType(lhsSigned ? lhs : rhs);
5592  }
5593  return destType;
5594}
5595
5596GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
5597  GVALinkage External = GVA_StrongExternal;
5598
5599  Linkage L = FD->getLinkage();
5600  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5601      FD->getType()->getLinkage() == UniqueExternalLinkage)
5602    L = UniqueExternalLinkage;
5603
5604  switch (L) {
5605  case NoLinkage:
5606  case InternalLinkage:
5607  case UniqueExternalLinkage:
5608    return GVA_Internal;
5609
5610  case ExternalLinkage:
5611    switch (FD->getTemplateSpecializationKind()) {
5612    case TSK_Undeclared:
5613    case TSK_ExplicitSpecialization:
5614      External = GVA_StrongExternal;
5615      break;
5616
5617    case TSK_ExplicitInstantiationDefinition:
5618      return GVA_ExplicitTemplateInstantiation;
5619
5620    case TSK_ExplicitInstantiationDeclaration:
5621    case TSK_ImplicitInstantiation:
5622      External = GVA_TemplateInstantiation;
5623      break;
5624    }
5625  }
5626
5627  if (!FD->isInlined())
5628    return External;
5629
5630  if (!getLangOptions().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
5631    // GNU or C99 inline semantics. Determine whether this symbol should be
5632    // externally visible.
5633    if (FD->isInlineDefinitionExternallyVisible())
5634      return External;
5635
5636    // C99 inline semantics, where the symbol is not externally visible.
5637    return GVA_C99Inline;
5638  }
5639
5640  // C++0x [temp.explicit]p9:
5641  //   [ Note: The intent is that an inline function that is the subject of
5642  //   an explicit instantiation declaration will still be implicitly
5643  //   instantiated when used so that the body can be considered for
5644  //   inlining, but that no out-of-line copy of the inline function would be
5645  //   generated in the translation unit. -- end note ]
5646  if (FD->getTemplateSpecializationKind()
5647                                       == TSK_ExplicitInstantiationDeclaration)
5648    return GVA_C99Inline;
5649
5650  return GVA_CXXInline;
5651}
5652
5653GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
5654  // If this is a static data member, compute the kind of template
5655  // specialization. Otherwise, this variable is not part of a
5656  // template.
5657  TemplateSpecializationKind TSK = TSK_Undeclared;
5658  if (VD->isStaticDataMember())
5659    TSK = VD->getTemplateSpecializationKind();
5660
5661  Linkage L = VD->getLinkage();
5662  if (L == ExternalLinkage && getLangOptions().CPlusPlus &&
5663      VD->getType()->getLinkage() == UniqueExternalLinkage)
5664    L = UniqueExternalLinkage;
5665
5666  switch (L) {
5667  case NoLinkage:
5668  case InternalLinkage:
5669  case UniqueExternalLinkage:
5670    return GVA_Internal;
5671
5672  case ExternalLinkage:
5673    switch (TSK) {
5674    case TSK_Undeclared:
5675    case TSK_ExplicitSpecialization:
5676      return GVA_StrongExternal;
5677
5678    case TSK_ExplicitInstantiationDeclaration:
5679      llvm_unreachable("Variable should not be instantiated");
5680      // Fall through to treat this like any other instantiation.
5681
5682    case TSK_ExplicitInstantiationDefinition:
5683      return GVA_ExplicitTemplateInstantiation;
5684
5685    case TSK_ImplicitInstantiation:
5686      return GVA_TemplateInstantiation;
5687    }
5688  }
5689
5690  return GVA_StrongExternal;
5691}
5692
5693bool ASTContext::DeclMustBeEmitted(const Decl *D) {
5694  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
5695    if (!VD->isFileVarDecl())
5696      return false;
5697  } else if (!isa<FunctionDecl>(D))
5698    return false;
5699
5700  // Weak references don't produce any output by themselves.
5701  if (D->hasAttr<WeakRefAttr>())
5702    return false;
5703
5704  // Aliases and used decls are required.
5705  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
5706    return true;
5707
5708  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
5709    // Forward declarations aren't required.
5710    if (!FD->isThisDeclarationADefinition())
5711      return false;
5712
5713    // Constructors and destructors are required.
5714    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
5715      return true;
5716
5717    // The key function for a class is required.
5718    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
5719      const CXXRecordDecl *RD = MD->getParent();
5720      if (MD->isOutOfLine() && RD->isDynamicClass()) {
5721        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
5722        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
5723          return true;
5724      }
5725    }
5726
5727    GVALinkage Linkage = GetGVALinkageForFunction(FD);
5728
5729    // static, static inline, always_inline, and extern inline functions can
5730    // always be deferred.  Normal inline functions can be deferred in C99/C++.
5731    // Implicit template instantiations can also be deferred in C++.
5732    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
5733        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
5734      return false;
5735    return true;
5736  }
5737
5738  const VarDecl *VD = cast<VarDecl>(D);
5739  assert(VD->isFileVarDecl() && "Expected file scoped var");
5740
5741  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
5742    return false;
5743
5744  // Structs that have non-trivial constructors or destructors are required.
5745
5746  // FIXME: Handle references.
5747  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
5748    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
5749      if (RD->hasDefinition() &&
5750          (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()))
5751        return true;
5752    }
5753  }
5754
5755  GVALinkage L = GetGVALinkageForVariable(VD);
5756  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
5757    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
5758      return false;
5759  }
5760
5761  return true;
5762}
5763
5764CXXABI::~CXXABI() {}
5765