ASTContext.cpp revision c586d5dd7a997321ea96d1d28213315f86778fc8 
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/CommentCommandTraits.h"
17#include "clang/AST/DeclCXX.h"
18#include "clang/AST/DeclObjC.h"
19#include "clang/AST/DeclTemplate.h"
20#include "clang/AST/TypeLoc.h"
21#include "clang/AST/Expr.h"
22#include "clang/AST/ExprCXX.h"
23#include "clang/AST/ExternalASTSource.h"
24#include "clang/AST/ASTMutationListener.h"
25#include "clang/AST/RecordLayout.h"
26#include "clang/AST/Mangle.h"
27#include "clang/Basic/Builtins.h"
28#include "clang/Basic/SourceManager.h"
29#include "clang/Basic/TargetInfo.h"
30#include "llvm/ADT/SmallString.h"
31#include "llvm/ADT/StringExtras.h"
32#include "llvm/Support/MathExtras.h"
33#include "llvm/Support/raw_ostream.h"
34#include "llvm/Support/Capacity.h"
35#include "CXXABI.h"
36#include <map>
37
38using namespace clang;
39
40unsigned ASTContext::NumImplicitDefaultConstructors;
41unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
42unsigned ASTContext::NumImplicitCopyConstructors;
43unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
44unsigned ASTContext::NumImplicitMoveConstructors;
45unsigned ASTContext::NumImplicitMoveConstructorsDeclared;
46unsigned ASTContext::NumImplicitCopyAssignmentOperators;
47unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
48unsigned ASTContext::NumImplicitMoveAssignmentOperators;
49unsigned ASTContext::NumImplicitMoveAssignmentOperatorsDeclared;
50unsigned ASTContext::NumImplicitDestructors;
51unsigned ASTContext::NumImplicitDestructorsDeclared;
52
53enum FloatingRank {
54  HalfRank, FloatRank, DoubleRank, LongDoubleRank
55};
56
57RawComment *ASTContext::getRawCommentForDeclNoCache(const Decl *D) const {
58  if (!CommentsLoaded && ExternalSource) {
59    ExternalSource->ReadComments();
60    CommentsLoaded = true;
61  }
62
63  assert(D);
64
65  // User can not attach documentation to implicit declarations.
66  if (D->isImplicit())
67    return NULL;
68
69  // User can not attach documentation to implicit instantiations.
70  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
71    if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
72      return NULL;
73  }
74
75  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
76    if (VD->isStaticDataMember() &&
77        VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
78      return NULL;
79  }
80
81  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(D)) {
82    if (CRD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
83      return NULL;
84  }
85
86  if (const EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
87    if (ED->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
88      return NULL;
89  }
90
91  // TODO: handle comments for function parameters properly.
92  if (isa<ParmVarDecl>(D))
93    return NULL;
94
95  // TODO: we could look up template parameter documentation in the template
96  // documentation.
97  if (isa<TemplateTypeParmDecl>(D) ||
98      isa<NonTypeTemplateParmDecl>(D) ||
99      isa<TemplateTemplateParmDecl>(D))
100    return NULL;
101
102  ArrayRef<RawComment *> RawComments = Comments.getComments();
103
104  // If there are no comments anywhere, we won't find anything.
105  if (RawComments.empty())
106    return NULL;
107
108  // Find declaration location.
109  // For Objective-C declarations we generally don't expect to have multiple
110  // declarators, thus use declaration starting location as the "declaration
111  // location".
112  // For all other declarations multiple declarators are used quite frequently,
113  // so we use the location of the identifier as the "declaration location".
114  SourceLocation DeclLoc;
115  if (isa<ObjCMethodDecl>(D) || isa<ObjCContainerDecl>(D) ||
116      isa<ObjCPropertyDecl>(D) ||
117      isa<RedeclarableTemplateDecl>(D) ||
118      isa<ClassTemplateSpecializationDecl>(D))
119    DeclLoc = D->getLocStart();
120  else
121    DeclLoc = D->getLocation();
122
123  // If the declaration doesn't map directly to a location in a file, we
124  // can't find the comment.
125  if (DeclLoc.isInvalid() || !DeclLoc.isFileID())
126    return NULL;
127
128  // Find the comment that occurs just after this declaration.
129  ArrayRef<RawComment *>::iterator Comment;
130  {
131    // When searching for comments during parsing, the comment we are looking
132    // for is usually among the last two comments we parsed -- check them
133    // first.
134    RawComment CommentAtDeclLoc(SourceMgr, SourceRange(DeclLoc));
135    BeforeThanCompare<RawComment> Compare(SourceMgr);
136    ArrayRef<RawComment *>::iterator MaybeBeforeDecl = RawComments.end() - 1;
137    bool Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
138    if (!Found && RawComments.size() >= 2) {
139      MaybeBeforeDecl--;
140      Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
141    }
142
143    if (Found) {
144      Comment = MaybeBeforeDecl + 1;
145      assert(Comment == std::lower_bound(RawComments.begin(), RawComments.end(),
146                                         &CommentAtDeclLoc, Compare));
147    } else {
148      // Slow path.
149      Comment = std::lower_bound(RawComments.begin(), RawComments.end(),
150                                 &CommentAtDeclLoc, Compare);
151    }
152  }
153
154  // Decompose the location for the declaration and find the beginning of the
155  // file buffer.
156  std::pair<FileID, unsigned> DeclLocDecomp = SourceMgr.getDecomposedLoc(DeclLoc);
157
158  // First check whether we have a trailing comment.
159  if (Comment != RawComments.end() &&
160      (*Comment)->isDocumentation() && (*Comment)->isTrailingComment() &&
161      (isa<FieldDecl>(D) || isa<EnumConstantDecl>(D) || isa<VarDecl>(D))) {
162    std::pair<FileID, unsigned> CommentBeginDecomp
163      = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getBegin());
164    // Check that Doxygen trailing comment comes after the declaration, starts
165    // on the same line and in the same file as the declaration.
166    if (DeclLocDecomp.first == CommentBeginDecomp.first &&
167        SourceMgr.getLineNumber(DeclLocDecomp.first, DeclLocDecomp.second)
168          == SourceMgr.getLineNumber(CommentBeginDecomp.first,
169                                     CommentBeginDecomp.second)) {
170      return *Comment;
171    }
172  }
173
174  // The comment just after the declaration was not a trailing comment.
175  // Let's look at the previous comment.
176  if (Comment == RawComments.begin())
177    return NULL;
178  --Comment;
179
180  // Check that we actually have a non-member Doxygen comment.
181  if (!(*Comment)->isDocumentation() || (*Comment)->isTrailingComment())
182    return NULL;
183
184  // Decompose the end of the comment.
185  std::pair<FileID, unsigned> CommentEndDecomp
186    = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getEnd());
187
188  // If the comment and the declaration aren't in the same file, then they
189  // aren't related.
190  if (DeclLocDecomp.first != CommentEndDecomp.first)
191    return NULL;
192
193  // Get the corresponding buffer.
194  bool Invalid = false;
195  const char *Buffer = SourceMgr.getBufferData(DeclLocDecomp.first,
196                                               &Invalid).data();
197  if (Invalid)
198    return NULL;
199
200  // Extract text between the comment and declaration.
201  StringRef Text(Buffer + CommentEndDecomp.second,
202                 DeclLocDecomp.second - CommentEndDecomp.second);
203
204  // There should be no other declarations or preprocessor directives between
205  // comment and declaration.
206  if (Text.find_first_of(",;{}#@") != StringRef::npos)
207    return NULL;
208
209  return *Comment;
210}
211
212namespace {
213/// If we have a 'templated' declaration for a template, adjust 'D' to
214/// refer to the actual template.
215/// If we have an implicit instantiation, adjust 'D' to refer to template.
216const Decl *adjustDeclToTemplate(const Decl *D) {
217  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
218    // Is this function declaration part of a function template?
219    if (const FunctionTemplateDecl *FTD = FD->getDescribedFunctionTemplate())
220      return FTD;
221
222    // Nothing to do if function is not an implicit instantiation.
223    if (FD->getTemplateSpecializationKind() != TSK_ImplicitInstantiation)
224      return D;
225
226    // Function is an implicit instantiation of a function template?
227    if (const FunctionTemplateDecl *FTD = FD->getPrimaryTemplate())
228      return FTD;
229
230    // Function is instantiated from a member definition of a class template?
231    if (const FunctionDecl *MemberDecl =
232            FD->getInstantiatedFromMemberFunction())
233      return MemberDecl;
234
235    return D;
236  }
237  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
238    // Static data member is instantiated from a member definition of a class
239    // template?
240    if (VD->isStaticDataMember())
241      if (const VarDecl *MemberDecl = VD->getInstantiatedFromStaticDataMember())
242        return MemberDecl;
243
244    return D;
245  }
246  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(D)) {
247    // Is this class declaration part of a class template?
248    if (const ClassTemplateDecl *CTD = CRD->getDescribedClassTemplate())
249      return CTD;
250
251    // Class is an implicit instantiation of a class template or partial
252    // specialization?
253    if (const ClassTemplateSpecializationDecl *CTSD =
254            dyn_cast<ClassTemplateSpecializationDecl>(CRD)) {
255      if (CTSD->getSpecializationKind() != TSK_ImplicitInstantiation)
256        return D;
257      llvm::PointerUnion<ClassTemplateDecl *,
258                         ClassTemplatePartialSpecializationDecl *>
259          PU = CTSD->getSpecializedTemplateOrPartial();
260      return PU.is<ClassTemplateDecl*>() ?
261          static_cast<const Decl*>(PU.get<ClassTemplateDecl *>()) :
262          static_cast<const Decl*>(
263              PU.get<ClassTemplatePartialSpecializationDecl *>());
264    }
265
266    // Class is instantiated from a member definition of a class template?
267    if (const MemberSpecializationInfo *Info =
268                   CRD->getMemberSpecializationInfo())
269      return Info->getInstantiatedFrom();
270
271    return D;
272  }
273  if (const EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
274    // Enum is instantiated from a member definition of a class template?
275    if (const EnumDecl *MemberDecl = ED->getInstantiatedFromMemberEnum())
276      return MemberDecl;
277
278    return D;
279  }
280  // FIXME: Adjust alias templates?
281  return D;
282}
283} // unnamed namespace
284
285const RawComment *ASTContext::getRawCommentForAnyRedecl(
286                                                const Decl *D,
287                                                const Decl **OriginalDecl) const {
288  D = adjustDeclToTemplate(D);
289
290  // Check whether we have cached a comment for this declaration already.
291  {
292    llvm::DenseMap<const Decl *, RawCommentAndCacheFlags>::iterator Pos =
293        RedeclComments.find(D);
294    if (Pos != RedeclComments.end()) {
295      const RawCommentAndCacheFlags &Raw = Pos->second;
296      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
297        if (OriginalDecl)
298          *OriginalDecl = Raw.getOriginalDecl();
299        return Raw.getRaw();
300      }
301    }
302  }
303
304  // Search for comments attached to declarations in the redeclaration chain.
305  const RawComment *RC = NULL;
306  const Decl *OriginalDeclForRC = NULL;
307  for (Decl::redecl_iterator I = D->redecls_begin(),
308                             E = D->redecls_end();
309       I != E; ++I) {
310    llvm::DenseMap<const Decl *, RawCommentAndCacheFlags>::iterator Pos =
311        RedeclComments.find(*I);
312    if (Pos != RedeclComments.end()) {
313      const RawCommentAndCacheFlags &Raw = Pos->second;
314      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
315        RC = Raw.getRaw();
316        OriginalDeclForRC = Raw.getOriginalDecl();
317        break;
318      }
319    } else {
320      RC = getRawCommentForDeclNoCache(*I);
321      OriginalDeclForRC = *I;
322      RawCommentAndCacheFlags Raw;
323      if (RC) {
324        Raw.setRaw(RC);
325        Raw.setKind(RawCommentAndCacheFlags::FromDecl);
326      } else
327        Raw.setKind(RawCommentAndCacheFlags::NoCommentInDecl);
328      Raw.setOriginalDecl(*I);
329      RedeclComments[*I] = Raw;
330      if (RC)
331        break;
332    }
333  }
334
335  // If we found a comment, it should be a documentation comment.
336  assert(!RC || RC->isDocumentation());
337
338  if (OriginalDecl)
339    *OriginalDecl = OriginalDeclForRC;
340
341  // Update cache for every declaration in the redeclaration chain.
342  RawCommentAndCacheFlags Raw;
343  Raw.setRaw(RC);
344  Raw.setKind(RawCommentAndCacheFlags::FromRedecl);
345  Raw.setOriginalDecl(OriginalDeclForRC);
346
347  for (Decl::redecl_iterator I = D->redecls_begin(),
348                             E = D->redecls_end();
349       I != E; ++I) {
350    RawCommentAndCacheFlags &R = RedeclComments[*I];
351    if (R.getKind() == RawCommentAndCacheFlags::NoCommentInDecl)
352      R = Raw;
353  }
354
355  return RC;
356}
357
358comments::FullComment *ASTContext::getCommentForDecl(const Decl *D) const {
359  D = adjustDeclToTemplate(D);
360  const Decl *Canonical = D->getCanonicalDecl();
361  llvm::DenseMap<const Decl *, comments::FullComment *>::iterator Pos =
362      ParsedComments.find(Canonical);
363  if (Pos != ParsedComments.end())
364    return Pos->second;
365
366  const Decl *OriginalDecl;
367  const RawComment *RC = getRawCommentForAnyRedecl(D, &OriginalDecl);
368  if (!RC)
369    return NULL;
370
371  // If the RawComment was attached to other redeclaration of this Decl, we
372  // should parse the comment in context of that other Decl.  This is important
373  // because comments can contain references to parameter names which can be
374  // different across redeclarations.
375  if (D != OriginalDecl)
376    return getCommentForDecl(OriginalDecl);
377
378  comments::FullComment *FC = RC->parse(*this, D);
379  ParsedComments[Canonical] = FC;
380  return FC;
381}
382
383void
384ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
385                                               TemplateTemplateParmDecl *Parm) {
386  ID.AddInteger(Parm->getDepth());
387  ID.AddInteger(Parm->getPosition());
388  ID.AddBoolean(Parm->isParameterPack());
389
390  TemplateParameterList *Params = Parm->getTemplateParameters();
391  ID.AddInteger(Params->size());
392  for (TemplateParameterList::const_iterator P = Params->begin(),
393                                          PEnd = Params->end();
394       P != PEnd; ++P) {
395    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
396      ID.AddInteger(0);
397      ID.AddBoolean(TTP->isParameterPack());
398      continue;
399    }
400
401    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
402      ID.AddInteger(1);
403      ID.AddBoolean(NTTP->isParameterPack());
404      ID.AddPointer(NTTP->getType().getCanonicalType().getAsOpaquePtr());
405      if (NTTP->isExpandedParameterPack()) {
406        ID.AddBoolean(true);
407        ID.AddInteger(NTTP->getNumExpansionTypes());
408        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
409          QualType T = NTTP->getExpansionType(I);
410          ID.AddPointer(T.getCanonicalType().getAsOpaquePtr());
411        }
412      } else
413        ID.AddBoolean(false);
414      continue;
415    }
416
417    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
418    ID.AddInteger(2);
419    Profile(ID, TTP);
420  }
421}
422
423TemplateTemplateParmDecl *
424ASTContext::getCanonicalTemplateTemplateParmDecl(
425                                          TemplateTemplateParmDecl *TTP) const {
426  // Check if we already have a canonical template template parameter.
427  llvm::FoldingSetNodeID ID;
428  CanonicalTemplateTemplateParm::Profile(ID, TTP);
429  void *InsertPos = 0;
430  CanonicalTemplateTemplateParm *Canonical
431    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
432  if (Canonical)
433    return Canonical->getParam();
434
435  // Build a canonical template parameter list.
436  TemplateParameterList *Params = TTP->getTemplateParameters();
437  SmallVector<NamedDecl *, 4> CanonParams;
438  CanonParams.reserve(Params->size());
439  for (TemplateParameterList::const_iterator P = Params->begin(),
440                                          PEnd = Params->end();
441       P != PEnd; ++P) {
442    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
443      CanonParams.push_back(
444                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
445                                               SourceLocation(),
446                                               SourceLocation(),
447                                               TTP->getDepth(),
448                                               TTP->getIndex(), 0, false,
449                                               TTP->isParameterPack()));
450    else if (NonTypeTemplateParmDecl *NTTP
451             = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
452      QualType T = getCanonicalType(NTTP->getType());
453      TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
454      NonTypeTemplateParmDecl *Param;
455      if (NTTP->isExpandedParameterPack()) {
456        SmallVector<QualType, 2> ExpandedTypes;
457        SmallVector<TypeSourceInfo *, 2> ExpandedTInfos;
458        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
459          ExpandedTypes.push_back(getCanonicalType(NTTP->getExpansionType(I)));
460          ExpandedTInfos.push_back(
461                                getTrivialTypeSourceInfo(ExpandedTypes.back()));
462        }
463
464        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
465                                                SourceLocation(),
466                                                SourceLocation(),
467                                                NTTP->getDepth(),
468                                                NTTP->getPosition(), 0,
469                                                T,
470                                                TInfo,
471                                                ExpandedTypes.data(),
472                                                ExpandedTypes.size(),
473                                                ExpandedTInfos.data());
474      } else {
475        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
476                                                SourceLocation(),
477                                                SourceLocation(),
478                                                NTTP->getDepth(),
479                                                NTTP->getPosition(), 0,
480                                                T,
481                                                NTTP->isParameterPack(),
482                                                TInfo);
483      }
484      CanonParams.push_back(Param);
485
486    } else
487      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
488                                           cast<TemplateTemplateParmDecl>(*P)));
489  }
490
491  TemplateTemplateParmDecl *CanonTTP
492    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
493                                       SourceLocation(), TTP->getDepth(),
494                                       TTP->getPosition(),
495                                       TTP->isParameterPack(),
496                                       0,
497                         TemplateParameterList::Create(*this, SourceLocation(),
498                                                       SourceLocation(),
499                                                       CanonParams.data(),
500                                                       CanonParams.size(),
501                                                       SourceLocation()));
502
503  // Get the new insert position for the node we care about.
504  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
505  assert(Canonical == 0 && "Shouldn't be in the map!");
506  (void)Canonical;
507
508  // Create the canonical template template parameter entry.
509  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
510  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
511  return CanonTTP;
512}
513
514CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
515  if (!LangOpts.CPlusPlus) return 0;
516
517  switch (T.getCXXABI()) {
518  case CXXABI_ARM:
519    return CreateARMCXXABI(*this);
520  case CXXABI_Itanium:
521    return CreateItaniumCXXABI(*this);
522  case CXXABI_Microsoft:
523    return CreateMicrosoftCXXABI(*this);
524  }
525  llvm_unreachable("Invalid CXXABI type!");
526}
527
528static const LangAS::Map *getAddressSpaceMap(const TargetInfo &T,
529                                             const LangOptions &LOpts) {
530  if (LOpts.FakeAddressSpaceMap) {
531    // The fake address space map must have a distinct entry for each
532    // language-specific address space.
533    static const unsigned FakeAddrSpaceMap[] = {
534      1, // opencl_global
535      2, // opencl_local
536      3, // opencl_constant
537      4, // cuda_device
538      5, // cuda_constant
539      6  // cuda_shared
540    };
541    return &FakeAddrSpaceMap;
542  } else {
543    return &T.getAddressSpaceMap();
544  }
545}
546
547ASTContext::ASTContext(LangOptions& LOpts, SourceManager &SM,
548                       const TargetInfo *t,
549                       IdentifierTable &idents, SelectorTable &sels,
550                       Builtin::Context &builtins,
551                       unsigned size_reserve,
552                       bool DelayInitialization)
553  : FunctionProtoTypes(this_()),
554    TemplateSpecializationTypes(this_()),
555    DependentTemplateSpecializationTypes(this_()),
556    SubstTemplateTemplateParmPacks(this_()),
557    GlobalNestedNameSpecifier(0),
558    Int128Decl(0), UInt128Decl(0),
559    BuiltinVaListDecl(0),
560    ObjCIdDecl(0), ObjCSelDecl(0), ObjCClassDecl(0), ObjCProtocolClassDecl(0),
561    CFConstantStringTypeDecl(0), ObjCInstanceTypeDecl(0),
562    FILEDecl(0),
563    jmp_bufDecl(0), sigjmp_bufDecl(0), ucontext_tDecl(0),
564    BlockDescriptorType(0), BlockDescriptorExtendedType(0),
565    cudaConfigureCallDecl(0),
566    NullTypeSourceInfo(QualType()),
567    FirstLocalImport(), LastLocalImport(),
568    SourceMgr(SM), LangOpts(LOpts),
569    AddrSpaceMap(0), Target(t), PrintingPolicy(LOpts),
570    Idents(idents), Selectors(sels),
571    BuiltinInfo(builtins),
572    DeclarationNames(*this),
573    ExternalSource(0), Listener(0),
574    Comments(SM), CommentsLoaded(false),
575    LastSDM(0, 0),
576    UniqueBlockByRefTypeID(0)
577{
578  if (size_reserve > 0) Types.reserve(size_reserve);
579  TUDecl = TranslationUnitDecl::Create(*this);
580
581  if (!DelayInitialization) {
582    assert(t && "No target supplied for ASTContext initialization");
583    InitBuiltinTypes(*t);
584  }
585}
586
587ASTContext::~ASTContext() {
588  // Release the DenseMaps associated with DeclContext objects.
589  // FIXME: Is this the ideal solution?
590  ReleaseDeclContextMaps();
591
592  // Call all of the deallocation functions.
593  for (unsigned I = 0, N = Deallocations.size(); I != N; ++I)
594    Deallocations[I].first(Deallocations[I].second);
595
596  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
597  // because they can contain DenseMaps.
598  for (llvm::DenseMap<const ObjCContainerDecl*,
599       const ASTRecordLayout*>::iterator
600       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
601    // Increment in loop to prevent using deallocated memory.
602    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
603      R->Destroy(*this);
604
605  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
606       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
607    // Increment in loop to prevent using deallocated memory.
608    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
609      R->Destroy(*this);
610  }
611
612  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
613                                                    AEnd = DeclAttrs.end();
614       A != AEnd; ++A)
615    A->second->~AttrVec();
616}
617
618void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
619  Deallocations.push_back(std::make_pair(Callback, Data));
620}
621
622void
623ASTContext::setExternalSource(OwningPtr<ExternalASTSource> &Source) {
624  ExternalSource.reset(Source.take());
625}
626
627void ASTContext::PrintStats() const {
628  llvm::errs() << "\n*** AST Context Stats:\n";
629  llvm::errs() << "  " << Types.size() << " types total.\n";
630
631  unsigned counts[] = {
632#define TYPE(Name, Parent) 0,
633#define ABSTRACT_TYPE(Name, Parent)
634#include "clang/AST/TypeNodes.def"
635    0 // Extra
636  };
637
638  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
639    Type *T = Types[i];
640    counts[(unsigned)T->getTypeClass()]++;
641  }
642
643  unsigned Idx = 0;
644  unsigned TotalBytes = 0;
645#define TYPE(Name, Parent)                                              \
646  if (counts[Idx])                                                      \
647    llvm::errs() << "    " << counts[Idx] << " " << #Name               \
648                 << " types\n";                                         \
649  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
650  ++Idx;
651#define ABSTRACT_TYPE(Name, Parent)
652#include "clang/AST/TypeNodes.def"
653
654  llvm::errs() << "Total bytes = " << TotalBytes << "\n";
655
656  // Implicit special member functions.
657  llvm::errs() << NumImplicitDefaultConstructorsDeclared << "/"
658               << NumImplicitDefaultConstructors
659               << " implicit default constructors created\n";
660  llvm::errs() << NumImplicitCopyConstructorsDeclared << "/"
661               << NumImplicitCopyConstructors
662               << " implicit copy constructors created\n";
663  if (getLangOpts().CPlusPlus)
664    llvm::errs() << NumImplicitMoveConstructorsDeclared << "/"
665                 << NumImplicitMoveConstructors
666                 << " implicit move constructors created\n";
667  llvm::errs() << NumImplicitCopyAssignmentOperatorsDeclared << "/"
668               << NumImplicitCopyAssignmentOperators
669               << " implicit copy assignment operators created\n";
670  if (getLangOpts().CPlusPlus)
671    llvm::errs() << NumImplicitMoveAssignmentOperatorsDeclared << "/"
672                 << NumImplicitMoveAssignmentOperators
673                 << " implicit move assignment operators created\n";
674  llvm::errs() << NumImplicitDestructorsDeclared << "/"
675               << NumImplicitDestructors
676               << " implicit destructors created\n";
677
678  if (ExternalSource.get()) {
679    llvm::errs() << "\n";
680    ExternalSource->PrintStats();
681  }
682
683  BumpAlloc.PrintStats();
684}
685
686TypedefDecl *ASTContext::getInt128Decl() const {
687  if (!Int128Decl) {
688    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(Int128Ty);
689    Int128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
690                                     getTranslationUnitDecl(),
691                                     SourceLocation(),
692                                     SourceLocation(),
693                                     &Idents.get("__int128_t"),
694                                     TInfo);
695  }
696
697  return Int128Decl;
698}
699
700TypedefDecl *ASTContext::getUInt128Decl() const {
701  if (!UInt128Decl) {
702    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(UnsignedInt128Ty);
703    UInt128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
704                                     getTranslationUnitDecl(),
705                                     SourceLocation(),
706                                     SourceLocation(),
707                                     &Idents.get("__uint128_t"),
708                                     TInfo);
709  }
710
711  return UInt128Decl;
712}
713
714void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
715  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
716  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
717  Types.push_back(Ty);
718}
719
720void ASTContext::InitBuiltinTypes(const TargetInfo &Target) {
721  assert((!this->Target || this->Target == &Target) &&
722         "Incorrect target reinitialization");
723  assert(VoidTy.isNull() && "Context reinitialized?");
724
725  this->Target = &Target;
726
727  ABI.reset(createCXXABI(Target));
728  AddrSpaceMap = getAddressSpaceMap(Target, LangOpts);
729
730  // C99 6.2.5p19.
731  InitBuiltinType(VoidTy,              BuiltinType::Void);
732
733  // C99 6.2.5p2.
734  InitBuiltinType(BoolTy,              BuiltinType::Bool);
735  // C99 6.2.5p3.
736  if (LangOpts.CharIsSigned)
737    InitBuiltinType(CharTy,            BuiltinType::Char_S);
738  else
739    InitBuiltinType(CharTy,            BuiltinType::Char_U);
740  // C99 6.2.5p4.
741  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
742  InitBuiltinType(ShortTy,             BuiltinType::Short);
743  InitBuiltinType(IntTy,               BuiltinType::Int);
744  InitBuiltinType(LongTy,              BuiltinType::Long);
745  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
746
747  // C99 6.2.5p6.
748  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
749  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
750  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
751  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
752  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
753
754  // C99 6.2.5p10.
755  InitBuiltinType(FloatTy,             BuiltinType::Float);
756  InitBuiltinType(DoubleTy,            BuiltinType::Double);
757  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
758
759  // GNU extension, 128-bit integers.
760  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
761  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
762
763  if (LangOpts.CPlusPlus) { // C++ 3.9.1p5
764    if (TargetInfo::isTypeSigned(Target.getWCharType()))
765      InitBuiltinType(WCharTy,           BuiltinType::WChar_S);
766    else  // -fshort-wchar makes wchar_t be unsigned.
767      InitBuiltinType(WCharTy,           BuiltinType::WChar_U);
768  } else // C99
769    WCharTy = getFromTargetType(Target.getWCharType());
770
771  WIntTy = getFromTargetType(Target.getWIntType());
772
773  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
774    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
775  else // C99
776    Char16Ty = getFromTargetType(Target.getChar16Type());
777
778  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
779    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
780  else // C99
781    Char32Ty = getFromTargetType(Target.getChar32Type());
782
783  // Placeholder type for type-dependent expressions whose type is
784  // completely unknown. No code should ever check a type against
785  // DependentTy and users should never see it; however, it is here to
786  // help diagnose failures to properly check for type-dependent
787  // expressions.
788  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
789
790  // Placeholder type for functions.
791  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
792
793  // Placeholder type for bound members.
794  InitBuiltinType(BoundMemberTy,       BuiltinType::BoundMember);
795
796  // Placeholder type for pseudo-objects.
797  InitBuiltinType(PseudoObjectTy,      BuiltinType::PseudoObject);
798
799  // "any" type; useful for debugger-like clients.
800  InitBuiltinType(UnknownAnyTy,        BuiltinType::UnknownAny);
801
802  // Placeholder type for unbridged ARC casts.
803  InitBuiltinType(ARCUnbridgedCastTy,  BuiltinType::ARCUnbridgedCast);
804
805  // C99 6.2.5p11.
806  FloatComplexTy      = getComplexType(FloatTy);
807  DoubleComplexTy     = getComplexType(DoubleTy);
808  LongDoubleComplexTy = getComplexType(LongDoubleTy);
809
810  // Builtin types for 'id', 'Class', and 'SEL'.
811  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
812  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
813  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
814
815  // Builtin type for __objc_yes and __objc_no
816  ObjCBuiltinBoolTy = (Target.useSignedCharForObjCBool() ?
817                       SignedCharTy : BoolTy);
818
819  ObjCConstantStringType = QualType();
820
821  // void * type
822  VoidPtrTy = getPointerType(VoidTy);
823
824  // nullptr type (C++0x 2.14.7)
825  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
826
827  // half type (OpenCL 6.1.1.1) / ARM NEON __fp16
828  InitBuiltinType(HalfTy, BuiltinType::Half);
829
830  // Builtin type used to help define __builtin_va_list.
831  VaListTagTy = QualType();
832}
833
834DiagnosticsEngine &ASTContext::getDiagnostics() const {
835  return SourceMgr.getDiagnostics();
836}
837
838AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
839  AttrVec *&Result = DeclAttrs[D];
840  if (!Result) {
841    void *Mem = Allocate(sizeof(AttrVec));
842    Result = new (Mem) AttrVec;
843  }
844
845  return *Result;
846}
847
848/// \brief Erase the attributes corresponding to the given declaration.
849void ASTContext::eraseDeclAttrs(const Decl *D) {
850  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
851  if (Pos != DeclAttrs.end()) {
852    Pos->second->~AttrVec();
853    DeclAttrs.erase(Pos);
854  }
855}
856
857MemberSpecializationInfo *
858ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
859  assert(Var->isStaticDataMember() && "Not a static data member");
860  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
861    = InstantiatedFromStaticDataMember.find(Var);
862  if (Pos == InstantiatedFromStaticDataMember.end())
863    return 0;
864
865  return Pos->second;
866}
867
868void
869ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
870                                                TemplateSpecializationKind TSK,
871                                          SourceLocation PointOfInstantiation) {
872  assert(Inst->isStaticDataMember() && "Not a static data member");
873  assert(Tmpl->isStaticDataMember() && "Not a static data member");
874  assert(!InstantiatedFromStaticDataMember[Inst] &&
875         "Already noted what static data member was instantiated from");
876  InstantiatedFromStaticDataMember[Inst]
877    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
878}
879
880FunctionDecl *ASTContext::getClassScopeSpecializationPattern(
881                                                     const FunctionDecl *FD){
882  assert(FD && "Specialization is 0");
883  llvm::DenseMap<const FunctionDecl*, FunctionDecl *>::const_iterator Pos
884    = ClassScopeSpecializationPattern.find(FD);
885  if (Pos == ClassScopeSpecializationPattern.end())
886    return 0;
887
888  return Pos->second;
889}
890
891void ASTContext::setClassScopeSpecializationPattern(FunctionDecl *FD,
892                                        FunctionDecl *Pattern) {
893  assert(FD && "Specialization is 0");
894  assert(Pattern && "Class scope specialization pattern is 0");
895  ClassScopeSpecializationPattern[FD] = Pattern;
896}
897
898NamedDecl *
899ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
900  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
901    = InstantiatedFromUsingDecl.find(UUD);
902  if (Pos == InstantiatedFromUsingDecl.end())
903    return 0;
904
905  return Pos->second;
906}
907
908void
909ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
910  assert((isa<UsingDecl>(Pattern) ||
911          isa<UnresolvedUsingValueDecl>(Pattern) ||
912          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
913         "pattern decl is not a using decl");
914  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
915  InstantiatedFromUsingDecl[Inst] = Pattern;
916}
917
918UsingShadowDecl *
919ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
920  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
921    = InstantiatedFromUsingShadowDecl.find(Inst);
922  if (Pos == InstantiatedFromUsingShadowDecl.end())
923    return 0;
924
925  return Pos->second;
926}
927
928void
929ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
930                                               UsingShadowDecl *Pattern) {
931  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
932  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
933}
934
935FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
936  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
937    = InstantiatedFromUnnamedFieldDecl.find(Field);
938  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
939    return 0;
940
941  return Pos->second;
942}
943
944void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
945                                                     FieldDecl *Tmpl) {
946  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
947  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
948  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
949         "Already noted what unnamed field was instantiated from");
950
951  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
952}
953
954bool ASTContext::ZeroBitfieldFollowsNonBitfield(const FieldDecl *FD,
955                                    const FieldDecl *LastFD) const {
956  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
957          FD->getBitWidthValue(*this) == 0);
958}
959
960bool ASTContext::ZeroBitfieldFollowsBitfield(const FieldDecl *FD,
961                                             const FieldDecl *LastFD) const {
962  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
963          FD->getBitWidthValue(*this) == 0 &&
964          LastFD->getBitWidthValue(*this) != 0);
965}
966
967bool ASTContext::BitfieldFollowsBitfield(const FieldDecl *FD,
968                                         const FieldDecl *LastFD) const {
969  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
970          FD->getBitWidthValue(*this) &&
971          LastFD->getBitWidthValue(*this));
972}
973
974bool ASTContext::NonBitfieldFollowsBitfield(const FieldDecl *FD,
975                                         const FieldDecl *LastFD) const {
976  return (!FD->isBitField() && LastFD && LastFD->isBitField() &&
977          LastFD->getBitWidthValue(*this));
978}
979
980bool ASTContext::BitfieldFollowsNonBitfield(const FieldDecl *FD,
981                                             const FieldDecl *LastFD) const {
982  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
983          FD->getBitWidthValue(*this));
984}
985
986ASTContext::overridden_cxx_method_iterator
987ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
988  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
989    = OverriddenMethods.find(Method);
990  if (Pos == OverriddenMethods.end())
991    return 0;
992
993  return Pos->second.begin();
994}
995
996ASTContext::overridden_cxx_method_iterator
997ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
998  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
999    = OverriddenMethods.find(Method);
1000  if (Pos == OverriddenMethods.end())
1001    return 0;
1002
1003  return Pos->second.end();
1004}
1005
1006unsigned
1007ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
1008  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1009    = OverriddenMethods.find(Method);
1010  if (Pos == OverriddenMethods.end())
1011    return 0;
1012
1013  return Pos->second.size();
1014}
1015
1016void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
1017                                     const CXXMethodDecl *Overridden) {
1018  OverriddenMethods[Method].push_back(Overridden);
1019}
1020
1021void ASTContext::addedLocalImportDecl(ImportDecl *Import) {
1022  assert(!Import->NextLocalImport && "Import declaration already in the chain");
1023  assert(!Import->isFromASTFile() && "Non-local import declaration");
1024  if (!FirstLocalImport) {
1025    FirstLocalImport = Import;
1026    LastLocalImport = Import;
1027    return;
1028  }
1029
1030  LastLocalImport->NextLocalImport = Import;
1031  LastLocalImport = Import;
1032}
1033
1034//===----------------------------------------------------------------------===//
1035//                         Type Sizing and Analysis
1036//===----------------------------------------------------------------------===//
1037
1038/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
1039/// scalar floating point type.
1040const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
1041  const BuiltinType *BT = T->getAs<BuiltinType>();
1042  assert(BT && "Not a floating point type!");
1043  switch (BT->getKind()) {
1044  default: llvm_unreachable("Not a floating point type!");
1045  case BuiltinType::Half:       return Target->getHalfFormat();
1046  case BuiltinType::Float:      return Target->getFloatFormat();
1047  case BuiltinType::Double:     return Target->getDoubleFormat();
1048  case BuiltinType::LongDouble: return Target->getLongDoubleFormat();
1049  }
1050}
1051
1052/// getDeclAlign - Return a conservative estimate of the alignment of the
1053/// specified decl.  Note that bitfields do not have a valid alignment, so
1054/// this method will assert on them.
1055/// If @p RefAsPointee, references are treated like their underlying type
1056/// (for alignof), else they're treated like pointers (for CodeGen).
1057CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) const {
1058  unsigned Align = Target->getCharWidth();
1059
1060  bool UseAlignAttrOnly = false;
1061  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
1062    Align = AlignFromAttr;
1063
1064    // __attribute__((aligned)) can increase or decrease alignment
1065    // *except* on a struct or struct member, where it only increases
1066    // alignment unless 'packed' is also specified.
1067    //
1068    // It is an error for alignas to decrease alignment, so we can
1069    // ignore that possibility;  Sema should diagnose it.
1070    if (isa<FieldDecl>(D)) {
1071      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
1072        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1073    } else {
1074      UseAlignAttrOnly = true;
1075    }
1076  }
1077  else if (isa<FieldDecl>(D))
1078      UseAlignAttrOnly =
1079        D->hasAttr<PackedAttr>() ||
1080        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1081
1082  // If we're using the align attribute only, just ignore everything
1083  // else about the declaration and its type.
1084  if (UseAlignAttrOnly) {
1085    // do nothing
1086
1087  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
1088    QualType T = VD->getType();
1089    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
1090      if (RefAsPointee)
1091        T = RT->getPointeeType();
1092      else
1093        T = getPointerType(RT->getPointeeType());
1094    }
1095    if (!T->isIncompleteType() && !T->isFunctionType()) {
1096      // Adjust alignments of declarations with array type by the
1097      // large-array alignment on the target.
1098      unsigned MinWidth = Target->getLargeArrayMinWidth();
1099      const ArrayType *arrayType;
1100      if (MinWidth && (arrayType = getAsArrayType(T))) {
1101        if (isa<VariableArrayType>(arrayType))
1102          Align = std::max(Align, Target->getLargeArrayAlign());
1103        else if (isa<ConstantArrayType>(arrayType) &&
1104                 MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
1105          Align = std::max(Align, Target->getLargeArrayAlign());
1106
1107        // Walk through any array types while we're at it.
1108        T = getBaseElementType(arrayType);
1109      }
1110      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
1111    }
1112
1113    // Fields can be subject to extra alignment constraints, like if
1114    // the field is packed, the struct is packed, or the struct has a
1115    // a max-field-alignment constraint (#pragma pack).  So calculate
1116    // the actual alignment of the field within the struct, and then
1117    // (as we're expected to) constrain that by the alignment of the type.
1118    if (const FieldDecl *field = dyn_cast<FieldDecl>(VD)) {
1119      // So calculate the alignment of the field.
1120      const ASTRecordLayout &layout = getASTRecordLayout(field->getParent());
1121
1122      // Start with the record's overall alignment.
1123      unsigned fieldAlign = toBits(layout.getAlignment());
1124
1125      // Use the GCD of that and the offset within the record.
1126      uint64_t offset = layout.getFieldOffset(field->getFieldIndex());
1127      if (offset > 0) {
1128        // Alignment is always a power of 2, so the GCD will be a power of 2,
1129        // which means we get to do this crazy thing instead of Euclid's.
1130        uint64_t lowBitOfOffset = offset & (~offset + 1);
1131        if (lowBitOfOffset < fieldAlign)
1132          fieldAlign = static_cast<unsigned>(lowBitOfOffset);
1133      }
1134
1135      Align = std::min(Align, fieldAlign);
1136    }
1137  }
1138
1139  return toCharUnitsFromBits(Align);
1140}
1141
1142// getTypeInfoDataSizeInChars - Return the size of a type, in
1143// chars. If the type is a record, its data size is returned.  This is
1144// the size of the memcpy that's performed when assigning this type
1145// using a trivial copy/move assignment operator.
1146std::pair<CharUnits, CharUnits>
1147ASTContext::getTypeInfoDataSizeInChars(QualType T) const {
1148  std::pair<CharUnits, CharUnits> sizeAndAlign = getTypeInfoInChars(T);
1149
1150  // In C++, objects can sometimes be allocated into the tail padding
1151  // of a base-class subobject.  We decide whether that's possible
1152  // during class layout, so here we can just trust the layout results.
1153  if (getLangOpts().CPlusPlus) {
1154    if (const RecordType *RT = T->getAs<RecordType>()) {
1155      const ASTRecordLayout &layout = getASTRecordLayout(RT->getDecl());
1156      sizeAndAlign.first = layout.getDataSize();
1157    }
1158  }
1159
1160  return sizeAndAlign;
1161}
1162
1163std::pair<CharUnits, CharUnits>
1164ASTContext::getTypeInfoInChars(const Type *T) const {
1165  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
1166  return std::make_pair(toCharUnitsFromBits(Info.first),
1167                        toCharUnitsFromBits(Info.second));
1168}
1169
1170std::pair<CharUnits, CharUnits>
1171ASTContext::getTypeInfoInChars(QualType T) const {
1172  return getTypeInfoInChars(T.getTypePtr());
1173}
1174
1175std::pair<uint64_t, unsigned> ASTContext::getTypeInfo(const Type *T) const {
1176  TypeInfoMap::iterator it = MemoizedTypeInfo.find(T);
1177  if (it != MemoizedTypeInfo.end())
1178    return it->second;
1179
1180  std::pair<uint64_t, unsigned> Info = getTypeInfoImpl(T);
1181  MemoizedTypeInfo.insert(std::make_pair(T, Info));
1182  return Info;
1183}
1184
1185/// getTypeInfoImpl - Return the size of the specified type, in bits.  This
1186/// method does not work on incomplete types.
1187///
1188/// FIXME: Pointers into different addr spaces could have different sizes and
1189/// alignment requirements: getPointerInfo should take an AddrSpace, this
1190/// should take a QualType, &c.
1191std::pair<uint64_t, unsigned>
1192ASTContext::getTypeInfoImpl(const Type *T) const {
1193  uint64_t Width=0;
1194  unsigned Align=8;
1195  switch (T->getTypeClass()) {
1196#define TYPE(Class, Base)
1197#define ABSTRACT_TYPE(Class, Base)
1198#define NON_CANONICAL_TYPE(Class, Base)
1199#define DEPENDENT_TYPE(Class, Base) case Type::Class:
1200#include "clang/AST/TypeNodes.def"
1201    llvm_unreachable("Should not see dependent types");
1202
1203  case Type::FunctionNoProto:
1204  case Type::FunctionProto:
1205    // GCC extension: alignof(function) = 32 bits
1206    Width = 0;
1207    Align = 32;
1208    break;
1209
1210  case Type::IncompleteArray:
1211  case Type::VariableArray:
1212    Width = 0;
1213    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
1214    break;
1215
1216  case Type::ConstantArray: {
1217    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
1218
1219    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
1220    uint64_t Size = CAT->getSize().getZExtValue();
1221    assert((Size == 0 || EltInfo.first <= (uint64_t)(-1)/Size) &&
1222           "Overflow in array type bit size evaluation");
1223    Width = EltInfo.first*Size;
1224    Align = EltInfo.second;
1225    Width = llvm::RoundUpToAlignment(Width, Align);
1226    break;
1227  }
1228  case Type::ExtVector:
1229  case Type::Vector: {
1230    const VectorType *VT = cast<VectorType>(T);
1231    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
1232    Width = EltInfo.first*VT->getNumElements();
1233    Align = Width;
1234    // If the alignment is not a power of 2, round up to the next power of 2.
1235    // This happens for non-power-of-2 length vectors.
1236    if (Align & (Align-1)) {
1237      Align = llvm::NextPowerOf2(Align);
1238      Width = llvm::RoundUpToAlignment(Width, Align);
1239    }
1240    // Adjust the alignment based on the target max.
1241    uint64_t TargetVectorAlign = Target->getMaxVectorAlign();
1242    if (TargetVectorAlign && TargetVectorAlign < Align)
1243      Align = TargetVectorAlign;
1244    break;
1245  }
1246
1247  case Type::Builtin:
1248    switch (cast<BuiltinType>(T)->getKind()) {
1249    default: llvm_unreachable("Unknown builtin type!");
1250    case BuiltinType::Void:
1251      // GCC extension: alignof(void) = 8 bits.
1252      Width = 0;
1253      Align = 8;
1254      break;
1255
1256    case BuiltinType::Bool:
1257      Width = Target->getBoolWidth();
1258      Align = Target->getBoolAlign();
1259      break;
1260    case BuiltinType::Char_S:
1261    case BuiltinType::Char_U:
1262    case BuiltinType::UChar:
1263    case BuiltinType::SChar:
1264      Width = Target->getCharWidth();
1265      Align = Target->getCharAlign();
1266      break;
1267    case BuiltinType::WChar_S:
1268    case BuiltinType::WChar_U:
1269      Width = Target->getWCharWidth();
1270      Align = Target->getWCharAlign();
1271      break;
1272    case BuiltinType::Char16:
1273      Width = Target->getChar16Width();
1274      Align = Target->getChar16Align();
1275      break;
1276    case BuiltinType::Char32:
1277      Width = Target->getChar32Width();
1278      Align = Target->getChar32Align();
1279      break;
1280    case BuiltinType::UShort:
1281    case BuiltinType::Short:
1282      Width = Target->getShortWidth();
1283      Align = Target->getShortAlign();
1284      break;
1285    case BuiltinType::UInt:
1286    case BuiltinType::Int:
1287      Width = Target->getIntWidth();
1288      Align = Target->getIntAlign();
1289      break;
1290    case BuiltinType::ULong:
1291    case BuiltinType::Long:
1292      Width = Target->getLongWidth();
1293      Align = Target->getLongAlign();
1294      break;
1295    case BuiltinType::ULongLong:
1296    case BuiltinType::LongLong:
1297      Width = Target->getLongLongWidth();
1298      Align = Target->getLongLongAlign();
1299      break;
1300    case BuiltinType::Int128:
1301    case BuiltinType::UInt128:
1302      Width = 128;
1303      Align = 128; // int128_t is 128-bit aligned on all targets.
1304      break;
1305    case BuiltinType::Half:
1306      Width = Target->getHalfWidth();
1307      Align = Target->getHalfAlign();
1308      break;
1309    case BuiltinType::Float:
1310      Width = Target->getFloatWidth();
1311      Align = Target->getFloatAlign();
1312      break;
1313    case BuiltinType::Double:
1314      Width = Target->getDoubleWidth();
1315      Align = Target->getDoubleAlign();
1316      break;
1317    case BuiltinType::LongDouble:
1318      Width = Target->getLongDoubleWidth();
1319      Align = Target->getLongDoubleAlign();
1320      break;
1321    case BuiltinType::NullPtr:
1322      Width = Target->getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
1323      Align = Target->getPointerAlign(0); //   == sizeof(void*)
1324      break;
1325    case BuiltinType::ObjCId:
1326    case BuiltinType::ObjCClass:
1327    case BuiltinType::ObjCSel:
1328      Width = Target->getPointerWidth(0);
1329      Align = Target->getPointerAlign(0);
1330      break;
1331    }
1332    break;
1333  case Type::ObjCObjectPointer:
1334    Width = Target->getPointerWidth(0);
1335    Align = Target->getPointerAlign(0);
1336    break;
1337  case Type::BlockPointer: {
1338    unsigned AS = getTargetAddressSpace(
1339        cast<BlockPointerType>(T)->getPointeeType());
1340    Width = Target->getPointerWidth(AS);
1341    Align = Target->getPointerAlign(AS);
1342    break;
1343  }
1344  case Type::LValueReference:
1345  case Type::RValueReference: {
1346    // alignof and sizeof should never enter this code path here, so we go
1347    // the pointer route.
1348    unsigned AS = getTargetAddressSpace(
1349        cast<ReferenceType>(T)->getPointeeType());
1350    Width = Target->getPointerWidth(AS);
1351    Align = Target->getPointerAlign(AS);
1352    break;
1353  }
1354  case Type::Pointer: {
1355    unsigned AS = getTargetAddressSpace(cast<PointerType>(T)->getPointeeType());
1356    Width = Target->getPointerWidth(AS);
1357    Align = Target->getPointerAlign(AS);
1358    break;
1359  }
1360  case Type::MemberPointer: {
1361    const MemberPointerType *MPT = cast<MemberPointerType>(T);
1362    std::pair<uint64_t, unsigned> PtrDiffInfo =
1363      getTypeInfo(getPointerDiffType());
1364    Width = PtrDiffInfo.first * ABI->getMemberPointerSize(MPT);
1365    Align = PtrDiffInfo.second;
1366    break;
1367  }
1368  case Type::Complex: {
1369    // Complex types have the same alignment as their elements, but twice the
1370    // size.
1371    std::pair<uint64_t, unsigned> EltInfo =
1372      getTypeInfo(cast<ComplexType>(T)->getElementType());
1373    Width = EltInfo.first*2;
1374    Align = EltInfo.second;
1375    break;
1376  }
1377  case Type::ObjCObject:
1378    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
1379  case Type::ObjCInterface: {
1380    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
1381    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
1382    Width = toBits(Layout.getSize());
1383    Align = toBits(Layout.getAlignment());
1384    break;
1385  }
1386  case Type::Record:
1387  case Type::Enum: {
1388    const TagType *TT = cast<TagType>(T);
1389
1390    if (TT->getDecl()->isInvalidDecl()) {
1391      Width = 8;
1392      Align = 8;
1393      break;
1394    }
1395
1396    if (const EnumType *ET = dyn_cast<EnumType>(TT))
1397      return getTypeInfo(ET->getDecl()->getIntegerType());
1398
1399    const RecordType *RT = cast<RecordType>(TT);
1400    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
1401    Width = toBits(Layout.getSize());
1402    Align = toBits(Layout.getAlignment());
1403    break;
1404  }
1405
1406  case Type::SubstTemplateTypeParm:
1407    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
1408                       getReplacementType().getTypePtr());
1409
1410  case Type::Auto: {
1411    const AutoType *A = cast<AutoType>(T);
1412    assert(A->isDeduced() && "Cannot request the size of a dependent type");
1413    return getTypeInfo(A->getDeducedType().getTypePtr());
1414  }
1415
1416  case Type::Paren:
1417    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
1418
1419  case Type::Typedef: {
1420    const TypedefNameDecl *Typedef = cast<TypedefType>(T)->getDecl();
1421    std::pair<uint64_t, unsigned> Info
1422      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
1423    // If the typedef has an aligned attribute on it, it overrides any computed
1424    // alignment we have.  This violates the GCC documentation (which says that
1425    // attribute(aligned) can only round up) but matches its implementation.
1426    if (unsigned AttrAlign = Typedef->getMaxAlignment())
1427      Align = AttrAlign;
1428    else
1429      Align = Info.second;
1430    Width = Info.first;
1431    break;
1432  }
1433
1434  case Type::TypeOfExpr:
1435    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
1436                         .getTypePtr());
1437
1438  case Type::TypeOf:
1439    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
1440
1441  case Type::Decltype:
1442    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
1443                        .getTypePtr());
1444
1445  case Type::UnaryTransform:
1446    return getTypeInfo(cast<UnaryTransformType>(T)->getUnderlyingType());
1447
1448  case Type::Elaborated:
1449    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
1450
1451  case Type::Attributed:
1452    return getTypeInfo(
1453                  cast<AttributedType>(T)->getEquivalentType().getTypePtr());
1454
1455  case Type::TemplateSpecialization: {
1456    assert(getCanonicalType(T) != T &&
1457           "Cannot request the size of a dependent type");
1458    const TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T);
1459    // A type alias template specialization may refer to a typedef with the
1460    // aligned attribute on it.
1461    if (TST->isTypeAlias())
1462      return getTypeInfo(TST->getAliasedType().getTypePtr());
1463    else
1464      return getTypeInfo(getCanonicalType(T));
1465  }
1466
1467  case Type::Atomic: {
1468    std::pair<uint64_t, unsigned> Info
1469      = getTypeInfo(cast<AtomicType>(T)->getValueType());
1470    Width = Info.first;
1471    Align = Info.second;
1472    if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth() &&
1473        llvm::isPowerOf2_64(Width)) {
1474      // We can potentially perform lock-free atomic operations for this
1475      // type; promote the alignment appropriately.
1476      // FIXME: We could potentially promote the width here as well...
1477      // is that worthwhile?  (Non-struct atomic types generally have
1478      // power-of-two size anyway, but structs might not.  Requires a bit
1479      // of implementation work to make sure we zero out the extra bits.)
1480      Align = static_cast<unsigned>(Width);
1481    }
1482  }
1483
1484  }
1485
1486  assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
1487  return std::make_pair(Width, Align);
1488}
1489
1490/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1491CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1492  return CharUnits::fromQuantity(BitSize / getCharWidth());
1493}
1494
1495/// toBits - Convert a size in characters to a size in characters.
1496int64_t ASTContext::toBits(CharUnits CharSize) const {
1497  return CharSize.getQuantity() * getCharWidth();
1498}
1499
1500/// getTypeSizeInChars - Return the size of the specified type, in characters.
1501/// This method does not work on incomplete types.
1502CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1503  return toCharUnitsFromBits(getTypeSize(T));
1504}
1505CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1506  return toCharUnitsFromBits(getTypeSize(T));
1507}
1508
1509/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1510/// characters. This method does not work on incomplete types.
1511CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1512  return toCharUnitsFromBits(getTypeAlign(T));
1513}
1514CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1515  return toCharUnitsFromBits(getTypeAlign(T));
1516}
1517
1518/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1519/// type for the current target in bits.  This can be different than the ABI
1520/// alignment in cases where it is beneficial for performance to overalign
1521/// a data type.
1522unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1523  unsigned ABIAlign = getTypeAlign(T);
1524
1525  // Double and long long should be naturally aligned if possible.
1526  if (const ComplexType* CT = T->getAs<ComplexType>())
1527    T = CT->getElementType().getTypePtr();
1528  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1529      T->isSpecificBuiltinType(BuiltinType::LongLong) ||
1530      T->isSpecificBuiltinType(BuiltinType::ULongLong))
1531    return std::max(ABIAlign, (unsigned)getTypeSize(T));
1532
1533  return ABIAlign;
1534}
1535
1536/// DeepCollectObjCIvars -
1537/// This routine first collects all declared, but not synthesized, ivars in
1538/// super class and then collects all ivars, including those synthesized for
1539/// current class. This routine is used for implementation of current class
1540/// when all ivars, declared and synthesized are known.
1541///
1542void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1543                                      bool leafClass,
1544                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1545  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1546    DeepCollectObjCIvars(SuperClass, false, Ivars);
1547  if (!leafClass) {
1548    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
1549         E = OI->ivar_end(); I != E; ++I)
1550      Ivars.push_back(*I);
1551  } else {
1552    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1553    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1554         Iv= Iv->getNextIvar())
1555      Ivars.push_back(Iv);
1556  }
1557}
1558
1559/// CollectInheritedProtocols - Collect all protocols in current class and
1560/// those inherited by it.
1561void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1562                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1563  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1564    // We can use protocol_iterator here instead of
1565    // all_referenced_protocol_iterator since we are walking all categories.
1566    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
1567         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
1568      ObjCProtocolDecl *Proto = (*P);
1569      Protocols.insert(Proto->getCanonicalDecl());
1570      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1571           PE = Proto->protocol_end(); P != PE; ++P) {
1572        Protocols.insert((*P)->getCanonicalDecl());
1573        CollectInheritedProtocols(*P, Protocols);
1574      }
1575    }
1576
1577    // Categories of this Interface.
1578    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
1579         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
1580      CollectInheritedProtocols(CDeclChain, Protocols);
1581    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1582      while (SD) {
1583        CollectInheritedProtocols(SD, Protocols);
1584        SD = SD->getSuperClass();
1585      }
1586  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1587    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
1588         PE = OC->protocol_end(); P != PE; ++P) {
1589      ObjCProtocolDecl *Proto = (*P);
1590      Protocols.insert(Proto->getCanonicalDecl());
1591      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1592           PE = Proto->protocol_end(); P != PE; ++P)
1593        CollectInheritedProtocols(*P, Protocols);
1594    }
1595  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
1596    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
1597         PE = OP->protocol_end(); P != PE; ++P) {
1598      ObjCProtocolDecl *Proto = (*P);
1599      Protocols.insert(Proto->getCanonicalDecl());
1600      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1601           PE = Proto->protocol_end(); P != PE; ++P)
1602        CollectInheritedProtocols(*P, Protocols);
1603    }
1604  }
1605}
1606
1607unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
1608  unsigned count = 0;
1609  // Count ivars declared in class extension.
1610  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
1611       CDecl = CDecl->getNextClassExtension())
1612    count += CDecl->ivar_size();
1613
1614  // Count ivar defined in this class's implementation.  This
1615  // includes synthesized ivars.
1616  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
1617    count += ImplDecl->ivar_size();
1618
1619  return count;
1620}
1621
1622bool ASTContext::isSentinelNullExpr(const Expr *E) {
1623  if (!E)
1624    return false;
1625
1626  // nullptr_t is always treated as null.
1627  if (E->getType()->isNullPtrType()) return true;
1628
1629  if (E->getType()->isAnyPointerType() &&
1630      E->IgnoreParenCasts()->isNullPointerConstant(*this,
1631                                                Expr::NPC_ValueDependentIsNull))
1632    return true;
1633
1634  // Unfortunately, __null has type 'int'.
1635  if (isa<GNUNullExpr>(E)) return true;
1636
1637  return false;
1638}
1639
1640/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
1641ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
1642  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1643    I = ObjCImpls.find(D);
1644  if (I != ObjCImpls.end())
1645    return cast<ObjCImplementationDecl>(I->second);
1646  return 0;
1647}
1648/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
1649ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
1650  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1651    I = ObjCImpls.find(D);
1652  if (I != ObjCImpls.end())
1653    return cast<ObjCCategoryImplDecl>(I->second);
1654  return 0;
1655}
1656
1657/// \brief Set the implementation of ObjCInterfaceDecl.
1658void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1659                           ObjCImplementationDecl *ImplD) {
1660  assert(IFaceD && ImplD && "Passed null params");
1661  ObjCImpls[IFaceD] = ImplD;
1662}
1663/// \brief Set the implementation of ObjCCategoryDecl.
1664void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1665                           ObjCCategoryImplDecl *ImplD) {
1666  assert(CatD && ImplD && "Passed null params");
1667  ObjCImpls[CatD] = ImplD;
1668}
1669
1670ObjCInterfaceDecl *ASTContext::getObjContainingInterface(NamedDecl *ND) const {
1671  if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(ND->getDeclContext()))
1672    return ID;
1673  if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(ND->getDeclContext()))
1674    return CD->getClassInterface();
1675  if (ObjCImplDecl *IMD = dyn_cast<ObjCImplDecl>(ND->getDeclContext()))
1676    return IMD->getClassInterface();
1677
1678  return 0;
1679}
1680
1681/// \brief Get the copy initialization expression of VarDecl,or NULL if
1682/// none exists.
1683Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
1684  assert(VD && "Passed null params");
1685  assert(VD->hasAttr<BlocksAttr>() &&
1686         "getBlockVarCopyInits - not __block var");
1687  llvm::DenseMap<const VarDecl*, Expr*>::iterator
1688    I = BlockVarCopyInits.find(VD);
1689  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : 0;
1690}
1691
1692/// \brief Set the copy inialization expression of a block var decl.
1693void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
1694  assert(VD && Init && "Passed null params");
1695  assert(VD->hasAttr<BlocksAttr>() &&
1696         "setBlockVarCopyInits - not __block var");
1697  BlockVarCopyInits[VD] = Init;
1698}
1699
1700TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1701                                                 unsigned DataSize) const {
1702  if (!DataSize)
1703    DataSize = TypeLoc::getFullDataSizeForType(T);
1704  else
1705    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1706           "incorrect data size provided to CreateTypeSourceInfo!");
1707
1708  TypeSourceInfo *TInfo =
1709    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1710  new (TInfo) TypeSourceInfo(T);
1711  return TInfo;
1712}
1713
1714TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1715                                                     SourceLocation L) const {
1716  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1717  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
1718  return DI;
1719}
1720
1721const ASTRecordLayout &
1722ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
1723  return getObjCLayout(D, 0);
1724}
1725
1726const ASTRecordLayout &
1727ASTContext::getASTObjCImplementationLayout(
1728                                        const ObjCImplementationDecl *D) const {
1729  return getObjCLayout(D->getClassInterface(), D);
1730}
1731
1732//===----------------------------------------------------------------------===//
1733//                   Type creation/memoization methods
1734//===----------------------------------------------------------------------===//
1735
1736QualType
1737ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
1738  unsigned fastQuals = quals.getFastQualifiers();
1739  quals.removeFastQualifiers();
1740
1741  // Check if we've already instantiated this type.
1742  llvm::FoldingSetNodeID ID;
1743  ExtQuals::Profile(ID, baseType, quals);
1744  void *insertPos = 0;
1745  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
1746    assert(eq->getQualifiers() == quals);
1747    return QualType(eq, fastQuals);
1748  }
1749
1750  // If the base type is not canonical, make the appropriate canonical type.
1751  QualType canon;
1752  if (!baseType->isCanonicalUnqualified()) {
1753    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
1754    canonSplit.Quals.addConsistentQualifiers(quals);
1755    canon = getExtQualType(canonSplit.Ty, canonSplit.Quals);
1756
1757    // Re-find the insert position.
1758    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
1759  }
1760
1761  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
1762  ExtQualNodes.InsertNode(eq, insertPos);
1763  return QualType(eq, fastQuals);
1764}
1765
1766QualType
1767ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
1768  QualType CanT = getCanonicalType(T);
1769  if (CanT.getAddressSpace() == AddressSpace)
1770    return T;
1771
1772  // If we are composing extended qualifiers together, merge together
1773  // into one ExtQuals node.
1774  QualifierCollector Quals;
1775  const Type *TypeNode = Quals.strip(T);
1776
1777  // If this type already has an address space specified, it cannot get
1778  // another one.
1779  assert(!Quals.hasAddressSpace() &&
1780         "Type cannot be in multiple addr spaces!");
1781  Quals.addAddressSpace(AddressSpace);
1782
1783  return getExtQualType(TypeNode, Quals);
1784}
1785
1786QualType ASTContext::getObjCGCQualType(QualType T,
1787                                       Qualifiers::GC GCAttr) const {
1788  QualType CanT = getCanonicalType(T);
1789  if (CanT.getObjCGCAttr() == GCAttr)
1790    return T;
1791
1792  if (const PointerType *ptr = T->getAs<PointerType>()) {
1793    QualType Pointee = ptr->getPointeeType();
1794    if (Pointee->isAnyPointerType()) {
1795      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1796      return getPointerType(ResultType);
1797    }
1798  }
1799
1800  // If we are composing extended qualifiers together, merge together
1801  // into one ExtQuals node.
1802  QualifierCollector Quals;
1803  const Type *TypeNode = Quals.strip(T);
1804
1805  // If this type already has an ObjCGC specified, it cannot get
1806  // another one.
1807  assert(!Quals.hasObjCGCAttr() &&
1808         "Type cannot have multiple ObjCGCs!");
1809  Quals.addObjCGCAttr(GCAttr);
1810
1811  return getExtQualType(TypeNode, Quals);
1812}
1813
1814const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
1815                                                   FunctionType::ExtInfo Info) {
1816  if (T->getExtInfo() == Info)
1817    return T;
1818
1819  QualType Result;
1820  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
1821    Result = getFunctionNoProtoType(FNPT->getResultType(), Info);
1822  } else {
1823    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
1824    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
1825    EPI.ExtInfo = Info;
1826    Result = getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1827                             FPT->getNumArgs(), EPI);
1828  }
1829
1830  return cast<FunctionType>(Result.getTypePtr());
1831}
1832
1833/// getComplexType - Return the uniqued reference to the type for a complex
1834/// number with the specified element type.
1835QualType ASTContext::getComplexType(QualType T) const {
1836  // Unique pointers, to guarantee there is only one pointer of a particular
1837  // structure.
1838  llvm::FoldingSetNodeID ID;
1839  ComplexType::Profile(ID, T);
1840
1841  void *InsertPos = 0;
1842  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1843    return QualType(CT, 0);
1844
1845  // If the pointee type isn't canonical, this won't be a canonical type either,
1846  // so fill in the canonical type field.
1847  QualType Canonical;
1848  if (!T.isCanonical()) {
1849    Canonical = getComplexType(getCanonicalType(T));
1850
1851    // Get the new insert position for the node we care about.
1852    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1853    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1854  }
1855  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1856  Types.push_back(New);
1857  ComplexTypes.InsertNode(New, InsertPos);
1858  return QualType(New, 0);
1859}
1860
1861/// getPointerType - Return the uniqued reference to the type for a pointer to
1862/// the specified type.
1863QualType ASTContext::getPointerType(QualType T) const {
1864  // Unique pointers, to guarantee there is only one pointer of a particular
1865  // structure.
1866  llvm::FoldingSetNodeID ID;
1867  PointerType::Profile(ID, T);
1868
1869  void *InsertPos = 0;
1870  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1871    return QualType(PT, 0);
1872
1873  // If the pointee type isn't canonical, this won't be a canonical type either,
1874  // so fill in the canonical type field.
1875  QualType Canonical;
1876  if (!T.isCanonical()) {
1877    Canonical = getPointerType(getCanonicalType(T));
1878
1879    // Get the new insert position for the node we care about.
1880    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1881    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1882  }
1883  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1884  Types.push_back(New);
1885  PointerTypes.InsertNode(New, InsertPos);
1886  return QualType(New, 0);
1887}
1888
1889/// getBlockPointerType - Return the uniqued reference to the type for
1890/// a pointer to the specified block.
1891QualType ASTContext::getBlockPointerType(QualType T) const {
1892  assert(T->isFunctionType() && "block of function types only");
1893  // Unique pointers, to guarantee there is only one block of a particular
1894  // structure.
1895  llvm::FoldingSetNodeID ID;
1896  BlockPointerType::Profile(ID, T);
1897
1898  void *InsertPos = 0;
1899  if (BlockPointerType *PT =
1900        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1901    return QualType(PT, 0);
1902
1903  // If the block pointee type isn't canonical, this won't be a canonical
1904  // type either so fill in the canonical type field.
1905  QualType Canonical;
1906  if (!T.isCanonical()) {
1907    Canonical = getBlockPointerType(getCanonicalType(T));
1908
1909    // Get the new insert position for the node we care about.
1910    BlockPointerType *NewIP =
1911      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1912    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1913  }
1914  BlockPointerType *New
1915    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
1916  Types.push_back(New);
1917  BlockPointerTypes.InsertNode(New, InsertPos);
1918  return QualType(New, 0);
1919}
1920
1921/// getLValueReferenceType - Return the uniqued reference to the type for an
1922/// lvalue reference to the specified type.
1923QualType
1924ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
1925  assert(getCanonicalType(T) != OverloadTy &&
1926         "Unresolved overloaded function type");
1927
1928  // Unique pointers, to guarantee there is only one pointer of a particular
1929  // structure.
1930  llvm::FoldingSetNodeID ID;
1931  ReferenceType::Profile(ID, T, SpelledAsLValue);
1932
1933  void *InsertPos = 0;
1934  if (LValueReferenceType *RT =
1935        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1936    return QualType(RT, 0);
1937
1938  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1939
1940  // If the referencee type isn't canonical, this won't be a canonical type
1941  // either, so fill in the canonical type field.
1942  QualType Canonical;
1943  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
1944    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1945    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
1946
1947    // Get the new insert position for the node we care about.
1948    LValueReferenceType *NewIP =
1949      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1950    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1951  }
1952
1953  LValueReferenceType *New
1954    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
1955                                                     SpelledAsLValue);
1956  Types.push_back(New);
1957  LValueReferenceTypes.InsertNode(New, InsertPos);
1958
1959  return QualType(New, 0);
1960}
1961
1962/// getRValueReferenceType - Return the uniqued reference to the type for an
1963/// rvalue reference to the specified type.
1964QualType ASTContext::getRValueReferenceType(QualType T) const {
1965  // Unique pointers, to guarantee there is only one pointer of a particular
1966  // structure.
1967  llvm::FoldingSetNodeID ID;
1968  ReferenceType::Profile(ID, T, false);
1969
1970  void *InsertPos = 0;
1971  if (RValueReferenceType *RT =
1972        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
1973    return QualType(RT, 0);
1974
1975  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
1976
1977  // If the referencee type isn't canonical, this won't be a canonical type
1978  // either, so fill in the canonical type field.
1979  QualType Canonical;
1980  if (InnerRef || !T.isCanonical()) {
1981    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
1982    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
1983
1984    // Get the new insert position for the node we care about.
1985    RValueReferenceType *NewIP =
1986      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
1987    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1988  }
1989
1990  RValueReferenceType *New
1991    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
1992  Types.push_back(New);
1993  RValueReferenceTypes.InsertNode(New, InsertPos);
1994  return QualType(New, 0);
1995}
1996
1997/// getMemberPointerType - Return the uniqued reference to the type for a
1998/// member pointer to the specified type, in the specified class.
1999QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
2000  // Unique pointers, to guarantee there is only one pointer of a particular
2001  // structure.
2002  llvm::FoldingSetNodeID ID;
2003  MemberPointerType::Profile(ID, T, Cls);
2004
2005  void *InsertPos = 0;
2006  if (MemberPointerType *PT =
2007      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2008    return QualType(PT, 0);
2009
2010  // If the pointee or class type isn't canonical, this won't be a canonical
2011  // type either, so fill in the canonical type field.
2012  QualType Canonical;
2013  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
2014    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
2015
2016    // Get the new insert position for the node we care about.
2017    MemberPointerType *NewIP =
2018      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2019    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2020  }
2021  MemberPointerType *New
2022    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
2023  Types.push_back(New);
2024  MemberPointerTypes.InsertNode(New, InsertPos);
2025  return QualType(New, 0);
2026}
2027
2028/// getConstantArrayType - Return the unique reference to the type for an
2029/// array of the specified element type.
2030QualType ASTContext::getConstantArrayType(QualType EltTy,
2031                                          const llvm::APInt &ArySizeIn,
2032                                          ArrayType::ArraySizeModifier ASM,
2033                                          unsigned IndexTypeQuals) const {
2034  assert((EltTy->isDependentType() ||
2035          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
2036         "Constant array of VLAs is illegal!");
2037
2038  // Convert the array size into a canonical width matching the pointer size for
2039  // the target.
2040  llvm::APInt ArySize(ArySizeIn);
2041  ArySize =
2042    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
2043
2044  llvm::FoldingSetNodeID ID;
2045  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
2046
2047  void *InsertPos = 0;
2048  if (ConstantArrayType *ATP =
2049      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
2050    return QualType(ATP, 0);
2051
2052  // If the element type isn't canonical or has qualifiers, this won't
2053  // be a canonical type either, so fill in the canonical type field.
2054  QualType Canon;
2055  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2056    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2057    Canon = getConstantArrayType(QualType(canonSplit.Ty, 0), ArySize,
2058                                 ASM, IndexTypeQuals);
2059    Canon = getQualifiedType(Canon, canonSplit.Quals);
2060
2061    // Get the new insert position for the node we care about.
2062    ConstantArrayType *NewIP =
2063      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
2064    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2065  }
2066
2067  ConstantArrayType *New = new(*this,TypeAlignment)
2068    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
2069  ConstantArrayTypes.InsertNode(New, InsertPos);
2070  Types.push_back(New);
2071  return QualType(New, 0);
2072}
2073
2074/// getVariableArrayDecayedType - Turns the given type, which may be
2075/// variably-modified, into the corresponding type with all the known
2076/// sizes replaced with [*].
2077QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
2078  // Vastly most common case.
2079  if (!type->isVariablyModifiedType()) return type;
2080
2081  QualType result;
2082
2083  SplitQualType split = type.getSplitDesugaredType();
2084  const Type *ty = split.Ty;
2085  switch (ty->getTypeClass()) {
2086#define TYPE(Class, Base)
2087#define ABSTRACT_TYPE(Class, Base)
2088#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
2089#include "clang/AST/TypeNodes.def"
2090    llvm_unreachable("didn't desugar past all non-canonical types?");
2091
2092  // These types should never be variably-modified.
2093  case Type::Builtin:
2094  case Type::Complex:
2095  case Type::Vector:
2096  case Type::ExtVector:
2097  case Type::DependentSizedExtVector:
2098  case Type::ObjCObject:
2099  case Type::ObjCInterface:
2100  case Type::ObjCObjectPointer:
2101  case Type::Record:
2102  case Type::Enum:
2103  case Type::UnresolvedUsing:
2104  case Type::TypeOfExpr:
2105  case Type::TypeOf:
2106  case Type::Decltype:
2107  case Type::UnaryTransform:
2108  case Type::DependentName:
2109  case Type::InjectedClassName:
2110  case Type::TemplateSpecialization:
2111  case Type::DependentTemplateSpecialization:
2112  case Type::TemplateTypeParm:
2113  case Type::SubstTemplateTypeParmPack:
2114  case Type::Auto:
2115  case Type::PackExpansion:
2116    llvm_unreachable("type should never be variably-modified");
2117
2118  // These types can be variably-modified but should never need to
2119  // further decay.
2120  case Type::FunctionNoProto:
2121  case Type::FunctionProto:
2122  case Type::BlockPointer:
2123  case Type::MemberPointer:
2124    return type;
2125
2126  // These types can be variably-modified.  All these modifications
2127  // preserve structure except as noted by comments.
2128  // TODO: if we ever care about optimizing VLAs, there are no-op
2129  // optimizations available here.
2130  case Type::Pointer:
2131    result = getPointerType(getVariableArrayDecayedType(
2132                              cast<PointerType>(ty)->getPointeeType()));
2133    break;
2134
2135  case Type::LValueReference: {
2136    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
2137    result = getLValueReferenceType(
2138                 getVariableArrayDecayedType(lv->getPointeeType()),
2139                                    lv->isSpelledAsLValue());
2140    break;
2141  }
2142
2143  case Type::RValueReference: {
2144    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
2145    result = getRValueReferenceType(
2146                 getVariableArrayDecayedType(lv->getPointeeType()));
2147    break;
2148  }
2149
2150  case Type::Atomic: {
2151    const AtomicType *at = cast<AtomicType>(ty);
2152    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
2153    break;
2154  }
2155
2156  case Type::ConstantArray: {
2157    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
2158    result = getConstantArrayType(
2159                 getVariableArrayDecayedType(cat->getElementType()),
2160                                  cat->getSize(),
2161                                  cat->getSizeModifier(),
2162                                  cat->getIndexTypeCVRQualifiers());
2163    break;
2164  }
2165
2166  case Type::DependentSizedArray: {
2167    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
2168    result = getDependentSizedArrayType(
2169                 getVariableArrayDecayedType(dat->getElementType()),
2170                                        dat->getSizeExpr(),
2171                                        dat->getSizeModifier(),
2172                                        dat->getIndexTypeCVRQualifiers(),
2173                                        dat->getBracketsRange());
2174    break;
2175  }
2176
2177  // Turn incomplete types into [*] types.
2178  case Type::IncompleteArray: {
2179    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
2180    result = getVariableArrayType(
2181                 getVariableArrayDecayedType(iat->getElementType()),
2182                                  /*size*/ 0,
2183                                  ArrayType::Normal,
2184                                  iat->getIndexTypeCVRQualifiers(),
2185                                  SourceRange());
2186    break;
2187  }
2188
2189  // Turn VLA types into [*] types.
2190  case Type::VariableArray: {
2191    const VariableArrayType *vat = cast<VariableArrayType>(ty);
2192    result = getVariableArrayType(
2193                 getVariableArrayDecayedType(vat->getElementType()),
2194                                  /*size*/ 0,
2195                                  ArrayType::Star,
2196                                  vat->getIndexTypeCVRQualifiers(),
2197                                  vat->getBracketsRange());
2198    break;
2199  }
2200  }
2201
2202  // Apply the top-level qualifiers from the original.
2203  return getQualifiedType(result, split.Quals);
2204}
2205
2206/// getVariableArrayType - Returns a non-unique reference to the type for a
2207/// variable array of the specified element type.
2208QualType ASTContext::getVariableArrayType(QualType EltTy,
2209                                          Expr *NumElts,
2210                                          ArrayType::ArraySizeModifier ASM,
2211                                          unsigned IndexTypeQuals,
2212                                          SourceRange Brackets) const {
2213  // Since we don't unique expressions, it isn't possible to unique VLA's
2214  // that have an expression provided for their size.
2215  QualType Canon;
2216
2217  // Be sure to pull qualifiers off the element type.
2218  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2219    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2220    Canon = getVariableArrayType(QualType(canonSplit.Ty, 0), NumElts, ASM,
2221                                 IndexTypeQuals, Brackets);
2222    Canon = getQualifiedType(Canon, canonSplit.Quals);
2223  }
2224
2225  VariableArrayType *New = new(*this, TypeAlignment)
2226    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
2227
2228  VariableArrayTypes.push_back(New);
2229  Types.push_back(New);
2230  return QualType(New, 0);
2231}
2232
2233/// getDependentSizedArrayType - Returns a non-unique reference to
2234/// the type for a dependently-sized array of the specified element
2235/// type.
2236QualType ASTContext::getDependentSizedArrayType(QualType elementType,
2237                                                Expr *numElements,
2238                                                ArrayType::ArraySizeModifier ASM,
2239                                                unsigned elementTypeQuals,
2240                                                SourceRange brackets) const {
2241  assert((!numElements || numElements->isTypeDependent() ||
2242          numElements->isValueDependent()) &&
2243         "Size must be type- or value-dependent!");
2244
2245  // Dependently-sized array types that do not have a specified number
2246  // of elements will have their sizes deduced from a dependent
2247  // initializer.  We do no canonicalization here at all, which is okay
2248  // because they can't be used in most locations.
2249  if (!numElements) {
2250    DependentSizedArrayType *newType
2251      = new (*this, TypeAlignment)
2252          DependentSizedArrayType(*this, elementType, QualType(),
2253                                  numElements, ASM, elementTypeQuals,
2254                                  brackets);
2255    Types.push_back(newType);
2256    return QualType(newType, 0);
2257  }
2258
2259  // Otherwise, we actually build a new type every time, but we
2260  // also build a canonical type.
2261
2262  SplitQualType canonElementType = getCanonicalType(elementType).split();
2263
2264  void *insertPos = 0;
2265  llvm::FoldingSetNodeID ID;
2266  DependentSizedArrayType::Profile(ID, *this,
2267                                   QualType(canonElementType.Ty, 0),
2268                                   ASM, elementTypeQuals, numElements);
2269
2270  // Look for an existing type with these properties.
2271  DependentSizedArrayType *canonTy =
2272    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2273
2274  // If we don't have one, build one.
2275  if (!canonTy) {
2276    canonTy = new (*this, TypeAlignment)
2277      DependentSizedArrayType(*this, QualType(canonElementType.Ty, 0),
2278                              QualType(), numElements, ASM, elementTypeQuals,
2279                              brackets);
2280    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
2281    Types.push_back(canonTy);
2282  }
2283
2284  // Apply qualifiers from the element type to the array.
2285  QualType canon = getQualifiedType(QualType(canonTy,0),
2286                                    canonElementType.Quals);
2287
2288  // If we didn't need extra canonicalization for the element type,
2289  // then just use that as our result.
2290  if (QualType(canonElementType.Ty, 0) == elementType)
2291    return canon;
2292
2293  // Otherwise, we need to build a type which follows the spelling
2294  // of the element type.
2295  DependentSizedArrayType *sugaredType
2296    = new (*this, TypeAlignment)
2297        DependentSizedArrayType(*this, elementType, canon, numElements,
2298                                ASM, elementTypeQuals, brackets);
2299  Types.push_back(sugaredType);
2300  return QualType(sugaredType, 0);
2301}
2302
2303QualType ASTContext::getIncompleteArrayType(QualType elementType,
2304                                            ArrayType::ArraySizeModifier ASM,
2305                                            unsigned elementTypeQuals) const {
2306  llvm::FoldingSetNodeID ID;
2307  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
2308
2309  void *insertPos = 0;
2310  if (IncompleteArrayType *iat =
2311       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
2312    return QualType(iat, 0);
2313
2314  // If the element type isn't canonical, this won't be a canonical type
2315  // either, so fill in the canonical type field.  We also have to pull
2316  // qualifiers off the element type.
2317  QualType canon;
2318
2319  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
2320    SplitQualType canonSplit = getCanonicalType(elementType).split();
2321    canon = getIncompleteArrayType(QualType(canonSplit.Ty, 0),
2322                                   ASM, elementTypeQuals);
2323    canon = getQualifiedType(canon, canonSplit.Quals);
2324
2325    // Get the new insert position for the node we care about.
2326    IncompleteArrayType *existing =
2327      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2328    assert(!existing && "Shouldn't be in the map!"); (void) existing;
2329  }
2330
2331  IncompleteArrayType *newType = new (*this, TypeAlignment)
2332    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
2333
2334  IncompleteArrayTypes.InsertNode(newType, insertPos);
2335  Types.push_back(newType);
2336  return QualType(newType, 0);
2337}
2338
2339/// getVectorType - Return the unique reference to a vector type of
2340/// the specified element type and size. VectorType must be a built-in type.
2341QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
2342                                   VectorType::VectorKind VecKind) const {
2343  assert(vecType->isBuiltinType());
2344
2345  // Check if we've already instantiated a vector of this type.
2346  llvm::FoldingSetNodeID ID;
2347  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
2348
2349  void *InsertPos = 0;
2350  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2351    return QualType(VTP, 0);
2352
2353  // If the element type isn't canonical, this won't be a canonical type either,
2354  // so fill in the canonical type field.
2355  QualType Canonical;
2356  if (!vecType.isCanonical()) {
2357    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
2358
2359    // Get the new insert position for the node we care about.
2360    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2361    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2362  }
2363  VectorType *New = new (*this, TypeAlignment)
2364    VectorType(vecType, NumElts, Canonical, VecKind);
2365  VectorTypes.InsertNode(New, InsertPos);
2366  Types.push_back(New);
2367  return QualType(New, 0);
2368}
2369
2370/// getExtVectorType - Return the unique reference to an extended vector type of
2371/// the specified element type and size. VectorType must be a built-in type.
2372QualType
2373ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
2374  assert(vecType->isBuiltinType() || vecType->isDependentType());
2375
2376  // Check if we've already instantiated a vector of this type.
2377  llvm::FoldingSetNodeID ID;
2378  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
2379                      VectorType::GenericVector);
2380  void *InsertPos = 0;
2381  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2382    return QualType(VTP, 0);
2383
2384  // If the element type isn't canonical, this won't be a canonical type either,
2385  // so fill in the canonical type field.
2386  QualType Canonical;
2387  if (!vecType.isCanonical()) {
2388    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
2389
2390    // Get the new insert position for the node we care about.
2391    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2392    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2393  }
2394  ExtVectorType *New = new (*this, TypeAlignment)
2395    ExtVectorType(vecType, NumElts, Canonical);
2396  VectorTypes.InsertNode(New, InsertPos);
2397  Types.push_back(New);
2398  return QualType(New, 0);
2399}
2400
2401QualType
2402ASTContext::getDependentSizedExtVectorType(QualType vecType,
2403                                           Expr *SizeExpr,
2404                                           SourceLocation AttrLoc) const {
2405  llvm::FoldingSetNodeID ID;
2406  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
2407                                       SizeExpr);
2408
2409  void *InsertPos = 0;
2410  DependentSizedExtVectorType *Canon
2411    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2412  DependentSizedExtVectorType *New;
2413  if (Canon) {
2414    // We already have a canonical version of this array type; use it as
2415    // the canonical type for a newly-built type.
2416    New = new (*this, TypeAlignment)
2417      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
2418                                  SizeExpr, AttrLoc);
2419  } else {
2420    QualType CanonVecTy = getCanonicalType(vecType);
2421    if (CanonVecTy == vecType) {
2422      New = new (*this, TypeAlignment)
2423        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
2424                                    AttrLoc);
2425
2426      DependentSizedExtVectorType *CanonCheck
2427        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2428      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
2429      (void)CanonCheck;
2430      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
2431    } else {
2432      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
2433                                                      SourceLocation());
2434      New = new (*this, TypeAlignment)
2435        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2436    }
2437  }
2438
2439  Types.push_back(New);
2440  return QualType(New, 0);
2441}
2442
2443/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
2444///
2445QualType
2446ASTContext::getFunctionNoProtoType(QualType ResultTy,
2447                                   const FunctionType::ExtInfo &Info) const {
2448  const CallingConv DefaultCC = Info.getCC();
2449  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2450                               CC_X86StdCall : DefaultCC;
2451  // Unique functions, to guarantee there is only one function of a particular
2452  // structure.
2453  llvm::FoldingSetNodeID ID;
2454  FunctionNoProtoType::Profile(ID, ResultTy, Info);
2455
2456  void *InsertPos = 0;
2457  if (FunctionNoProtoType *FT =
2458        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2459    return QualType(FT, 0);
2460
2461  QualType Canonical;
2462  if (!ResultTy.isCanonical() ||
2463      getCanonicalCallConv(CallConv) != CallConv) {
2464    Canonical =
2465      getFunctionNoProtoType(getCanonicalType(ResultTy),
2466                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
2467
2468    // Get the new insert position for the node we care about.
2469    FunctionNoProtoType *NewIP =
2470      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2471    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2472  }
2473
2474  FunctionProtoType::ExtInfo newInfo = Info.withCallingConv(CallConv);
2475  FunctionNoProtoType *New = new (*this, TypeAlignment)
2476    FunctionNoProtoType(ResultTy, Canonical, newInfo);
2477  Types.push_back(New);
2478  FunctionNoProtoTypes.InsertNode(New, InsertPos);
2479  return QualType(New, 0);
2480}
2481
2482/// getFunctionType - Return a normal function type with a typed argument
2483/// list.  isVariadic indicates whether the argument list includes '...'.
2484QualType
2485ASTContext::getFunctionType(QualType ResultTy,
2486                            const QualType *ArgArray, unsigned NumArgs,
2487                            const FunctionProtoType::ExtProtoInfo &EPI) const {
2488  // Unique functions, to guarantee there is only one function of a particular
2489  // structure.
2490  llvm::FoldingSetNodeID ID;
2491  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, EPI, *this);
2492
2493  void *InsertPos = 0;
2494  if (FunctionProtoType *FTP =
2495        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2496    return QualType(FTP, 0);
2497
2498  // Determine whether the type being created is already canonical or not.
2499  bool isCanonical =
2500    EPI.ExceptionSpecType == EST_None && ResultTy.isCanonical() &&
2501    !EPI.HasTrailingReturn;
2502  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
2503    if (!ArgArray[i].isCanonicalAsParam())
2504      isCanonical = false;
2505
2506  const CallingConv DefaultCC = EPI.ExtInfo.getCC();
2507  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2508                               CC_X86StdCall : DefaultCC;
2509
2510  // If this type isn't canonical, get the canonical version of it.
2511  // The exception spec is not part of the canonical type.
2512  QualType Canonical;
2513  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
2514    SmallVector<QualType, 16> CanonicalArgs;
2515    CanonicalArgs.reserve(NumArgs);
2516    for (unsigned i = 0; i != NumArgs; ++i)
2517      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
2518
2519    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
2520    CanonicalEPI.HasTrailingReturn = false;
2521    CanonicalEPI.ExceptionSpecType = EST_None;
2522    CanonicalEPI.NumExceptions = 0;
2523    CanonicalEPI.ExtInfo
2524      = CanonicalEPI.ExtInfo.withCallingConv(getCanonicalCallConv(CallConv));
2525
2526    Canonical = getFunctionType(getCanonicalType(ResultTy),
2527                                CanonicalArgs.data(), NumArgs,
2528                                CanonicalEPI);
2529
2530    // Get the new insert position for the node we care about.
2531    FunctionProtoType *NewIP =
2532      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2533    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2534  }
2535
2536  // FunctionProtoType objects are allocated with extra bytes after
2537  // them for three variable size arrays at the end:
2538  //  - parameter types
2539  //  - exception types
2540  //  - consumed-arguments flags
2541  // Instead of the exception types, there could be a noexcept
2542  // expression, or information used to resolve the exception
2543  // specification.
2544  size_t Size = sizeof(FunctionProtoType) +
2545                NumArgs * sizeof(QualType);
2546  if (EPI.ExceptionSpecType == EST_Dynamic) {
2547    Size += EPI.NumExceptions * sizeof(QualType);
2548  } else if (EPI.ExceptionSpecType == EST_ComputedNoexcept) {
2549    Size += sizeof(Expr*);
2550  } else if (EPI.ExceptionSpecType == EST_Uninstantiated) {
2551    Size += 2 * sizeof(FunctionDecl*);
2552  } else if (EPI.ExceptionSpecType == EST_Unevaluated) {
2553    Size += sizeof(FunctionDecl*);
2554  }
2555  if (EPI.ConsumedArguments)
2556    Size += NumArgs * sizeof(bool);
2557
2558  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
2559  FunctionProtoType::ExtProtoInfo newEPI = EPI;
2560  newEPI.ExtInfo = EPI.ExtInfo.withCallingConv(CallConv);
2561  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, Canonical, newEPI);
2562  Types.push_back(FTP);
2563  FunctionProtoTypes.InsertNode(FTP, InsertPos);
2564  return QualType(FTP, 0);
2565}
2566
2567#ifndef NDEBUG
2568static bool NeedsInjectedClassNameType(const RecordDecl *D) {
2569  if (!isa<CXXRecordDecl>(D)) return false;
2570  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
2571  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
2572    return true;
2573  if (RD->getDescribedClassTemplate() &&
2574      !isa<ClassTemplateSpecializationDecl>(RD))
2575    return true;
2576  return false;
2577}
2578#endif
2579
2580/// getInjectedClassNameType - Return the unique reference to the
2581/// injected class name type for the specified templated declaration.
2582QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
2583                                              QualType TST) const {
2584  assert(NeedsInjectedClassNameType(Decl));
2585  if (Decl->TypeForDecl) {
2586    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2587  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDecl()) {
2588    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
2589    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2590    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2591  } else {
2592    Type *newType =
2593      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
2594    Decl->TypeForDecl = newType;
2595    Types.push_back(newType);
2596  }
2597  return QualType(Decl->TypeForDecl, 0);
2598}
2599
2600/// getTypeDeclType - Return the unique reference to the type for the
2601/// specified type declaration.
2602QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) const {
2603  assert(Decl && "Passed null for Decl param");
2604  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
2605
2606  if (const TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Decl))
2607    return getTypedefType(Typedef);
2608
2609  assert(!isa<TemplateTypeParmDecl>(Decl) &&
2610         "Template type parameter types are always available.");
2611
2612  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
2613    assert(!Record->getPreviousDecl() &&
2614           "struct/union has previous declaration");
2615    assert(!NeedsInjectedClassNameType(Record));
2616    return getRecordType(Record);
2617  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
2618    assert(!Enum->getPreviousDecl() &&
2619           "enum has previous declaration");
2620    return getEnumType(Enum);
2621  } else if (const UnresolvedUsingTypenameDecl *Using =
2622               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
2623    Type *newType = new (*this, TypeAlignment) UnresolvedUsingType(Using);
2624    Decl->TypeForDecl = newType;
2625    Types.push_back(newType);
2626  } else
2627    llvm_unreachable("TypeDecl without a type?");
2628
2629  return QualType(Decl->TypeForDecl, 0);
2630}
2631
2632/// getTypedefType - Return the unique reference to the type for the
2633/// specified typedef name decl.
2634QualType
2635ASTContext::getTypedefType(const TypedefNameDecl *Decl,
2636                           QualType Canonical) const {
2637  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2638
2639  if (Canonical.isNull())
2640    Canonical = getCanonicalType(Decl->getUnderlyingType());
2641  TypedefType *newType = new(*this, TypeAlignment)
2642    TypedefType(Type::Typedef, Decl, Canonical);
2643  Decl->TypeForDecl = newType;
2644  Types.push_back(newType);
2645  return QualType(newType, 0);
2646}
2647
2648QualType ASTContext::getRecordType(const RecordDecl *Decl) const {
2649  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2650
2651  if (const RecordDecl *PrevDecl = Decl->getPreviousDecl())
2652    if (PrevDecl->TypeForDecl)
2653      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2654
2655  RecordType *newType = new (*this, TypeAlignment) RecordType(Decl);
2656  Decl->TypeForDecl = newType;
2657  Types.push_back(newType);
2658  return QualType(newType, 0);
2659}
2660
2661QualType ASTContext::getEnumType(const EnumDecl *Decl) const {
2662  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2663
2664  if (const EnumDecl *PrevDecl = Decl->getPreviousDecl())
2665    if (PrevDecl->TypeForDecl)
2666      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2667
2668  EnumType *newType = new (*this, TypeAlignment) EnumType(Decl);
2669  Decl->TypeForDecl = newType;
2670  Types.push_back(newType);
2671  return QualType(newType, 0);
2672}
2673
2674QualType ASTContext::getAttributedType(AttributedType::Kind attrKind,
2675                                       QualType modifiedType,
2676                                       QualType equivalentType) {
2677  llvm::FoldingSetNodeID id;
2678  AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
2679
2680  void *insertPos = 0;
2681  AttributedType *type = AttributedTypes.FindNodeOrInsertPos(id, insertPos);
2682  if (type) return QualType(type, 0);
2683
2684  QualType canon = getCanonicalType(equivalentType);
2685  type = new (*this, TypeAlignment)
2686           AttributedType(canon, attrKind, modifiedType, equivalentType);
2687
2688  Types.push_back(type);
2689  AttributedTypes.InsertNode(type, insertPos);
2690
2691  return QualType(type, 0);
2692}
2693
2694
2695/// \brief Retrieve a substitution-result type.
2696QualType
2697ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
2698                                         QualType Replacement) const {
2699  assert(Replacement.isCanonical()
2700         && "replacement types must always be canonical");
2701
2702  llvm::FoldingSetNodeID ID;
2703  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
2704  void *InsertPos = 0;
2705  SubstTemplateTypeParmType *SubstParm
2706    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2707
2708  if (!SubstParm) {
2709    SubstParm = new (*this, TypeAlignment)
2710      SubstTemplateTypeParmType(Parm, Replacement);
2711    Types.push_back(SubstParm);
2712    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2713  }
2714
2715  return QualType(SubstParm, 0);
2716}
2717
2718/// \brief Retrieve a
2719QualType ASTContext::getSubstTemplateTypeParmPackType(
2720                                          const TemplateTypeParmType *Parm,
2721                                              const TemplateArgument &ArgPack) {
2722#ifndef NDEBUG
2723  for (TemplateArgument::pack_iterator P = ArgPack.pack_begin(),
2724                                    PEnd = ArgPack.pack_end();
2725       P != PEnd; ++P) {
2726    assert(P->getKind() == TemplateArgument::Type &&"Pack contains a non-type");
2727    assert(P->getAsType().isCanonical() && "Pack contains non-canonical type");
2728  }
2729#endif
2730
2731  llvm::FoldingSetNodeID ID;
2732  SubstTemplateTypeParmPackType::Profile(ID, Parm, ArgPack);
2733  void *InsertPos = 0;
2734  if (SubstTemplateTypeParmPackType *SubstParm
2735        = SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos))
2736    return QualType(SubstParm, 0);
2737
2738  QualType Canon;
2739  if (!Parm->isCanonicalUnqualified()) {
2740    Canon = getCanonicalType(QualType(Parm, 0));
2741    Canon = getSubstTemplateTypeParmPackType(cast<TemplateTypeParmType>(Canon),
2742                                             ArgPack);
2743    SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos);
2744  }
2745
2746  SubstTemplateTypeParmPackType *SubstParm
2747    = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
2748                                                               ArgPack);
2749  Types.push_back(SubstParm);
2750  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2751  return QualType(SubstParm, 0);
2752}
2753
2754/// \brief Retrieve the template type parameter type for a template
2755/// parameter or parameter pack with the given depth, index, and (optionally)
2756/// name.
2757QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
2758                                             bool ParameterPack,
2759                                             TemplateTypeParmDecl *TTPDecl) const {
2760  llvm::FoldingSetNodeID ID;
2761  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, TTPDecl);
2762  void *InsertPos = 0;
2763  TemplateTypeParmType *TypeParm
2764    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2765
2766  if (TypeParm)
2767    return QualType(TypeParm, 0);
2768
2769  if (TTPDecl) {
2770    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
2771    TypeParm = new (*this, TypeAlignment) TemplateTypeParmType(TTPDecl, Canon);
2772
2773    TemplateTypeParmType *TypeCheck
2774      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2775    assert(!TypeCheck && "Template type parameter canonical type broken");
2776    (void)TypeCheck;
2777  } else
2778    TypeParm = new (*this, TypeAlignment)
2779      TemplateTypeParmType(Depth, Index, ParameterPack);
2780
2781  Types.push_back(TypeParm);
2782  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
2783
2784  return QualType(TypeParm, 0);
2785}
2786
2787TypeSourceInfo *
2788ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
2789                                              SourceLocation NameLoc,
2790                                        const TemplateArgumentListInfo &Args,
2791                                              QualType Underlying) const {
2792  assert(!Name.getAsDependentTemplateName() &&
2793         "No dependent template names here!");
2794  QualType TST = getTemplateSpecializationType(Name, Args, Underlying);
2795
2796  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
2797  TemplateSpecializationTypeLoc TL
2798    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
2799  TL.setTemplateKeywordLoc(SourceLocation());
2800  TL.setTemplateNameLoc(NameLoc);
2801  TL.setLAngleLoc(Args.getLAngleLoc());
2802  TL.setRAngleLoc(Args.getRAngleLoc());
2803  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
2804    TL.setArgLocInfo(i, Args[i].getLocInfo());
2805  return DI;
2806}
2807
2808QualType
2809ASTContext::getTemplateSpecializationType(TemplateName Template,
2810                                          const TemplateArgumentListInfo &Args,
2811                                          QualType Underlying) const {
2812  assert(!Template.getAsDependentTemplateName() &&
2813         "No dependent template names here!");
2814
2815  unsigned NumArgs = Args.size();
2816
2817  SmallVector<TemplateArgument, 4> ArgVec;
2818  ArgVec.reserve(NumArgs);
2819  for (unsigned i = 0; i != NumArgs; ++i)
2820    ArgVec.push_back(Args[i].getArgument());
2821
2822  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
2823                                       Underlying);
2824}
2825
2826#ifndef NDEBUG
2827static bool hasAnyPackExpansions(const TemplateArgument *Args,
2828                                 unsigned NumArgs) {
2829  for (unsigned I = 0; I != NumArgs; ++I)
2830    if (Args[I].isPackExpansion())
2831      return true;
2832
2833  return true;
2834}
2835#endif
2836
2837QualType
2838ASTContext::getTemplateSpecializationType(TemplateName Template,
2839                                          const TemplateArgument *Args,
2840                                          unsigned NumArgs,
2841                                          QualType Underlying) const {
2842  assert(!Template.getAsDependentTemplateName() &&
2843         "No dependent template names here!");
2844  // Look through qualified template names.
2845  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2846    Template = TemplateName(QTN->getTemplateDecl());
2847
2848  bool IsTypeAlias =
2849    Template.getAsTemplateDecl() &&
2850    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
2851  QualType CanonType;
2852  if (!Underlying.isNull())
2853    CanonType = getCanonicalType(Underlying);
2854  else {
2855    // We can get here with an alias template when the specialization contains
2856    // a pack expansion that does not match up with a parameter pack.
2857    assert((!IsTypeAlias || hasAnyPackExpansions(Args, NumArgs)) &&
2858           "Caller must compute aliased type");
2859    IsTypeAlias = false;
2860    CanonType = getCanonicalTemplateSpecializationType(Template, Args,
2861                                                       NumArgs);
2862  }
2863
2864  // Allocate the (non-canonical) template specialization type, but don't
2865  // try to unique it: these types typically have location information that
2866  // we don't unique and don't want to lose.
2867  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
2868                       sizeof(TemplateArgument) * NumArgs +
2869                       (IsTypeAlias? sizeof(QualType) : 0),
2870                       TypeAlignment);
2871  TemplateSpecializationType *Spec
2872    = new (Mem) TemplateSpecializationType(Template, Args, NumArgs, CanonType,
2873                                         IsTypeAlias ? Underlying : QualType());
2874
2875  Types.push_back(Spec);
2876  return QualType(Spec, 0);
2877}
2878
2879QualType
2880ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
2881                                                   const TemplateArgument *Args,
2882                                                   unsigned NumArgs) const {
2883  assert(!Template.getAsDependentTemplateName() &&
2884         "No dependent template names here!");
2885
2886  // Look through qualified template names.
2887  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2888    Template = TemplateName(QTN->getTemplateDecl());
2889
2890  // Build the canonical template specialization type.
2891  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
2892  SmallVector<TemplateArgument, 4> CanonArgs;
2893  CanonArgs.reserve(NumArgs);
2894  for (unsigned I = 0; I != NumArgs; ++I)
2895    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
2896
2897  // Determine whether this canonical template specialization type already
2898  // exists.
2899  llvm::FoldingSetNodeID ID;
2900  TemplateSpecializationType::Profile(ID, CanonTemplate,
2901                                      CanonArgs.data(), NumArgs, *this);
2902
2903  void *InsertPos = 0;
2904  TemplateSpecializationType *Spec
2905    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
2906
2907  if (!Spec) {
2908    // Allocate a new canonical template specialization type.
2909    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
2910                          sizeof(TemplateArgument) * NumArgs),
2911                         TypeAlignment);
2912    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
2913                                                CanonArgs.data(), NumArgs,
2914                                                QualType(), QualType());
2915    Types.push_back(Spec);
2916    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
2917  }
2918
2919  assert(Spec->isDependentType() &&
2920         "Non-dependent template-id type must have a canonical type");
2921  return QualType(Spec, 0);
2922}
2923
2924QualType
2925ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
2926                              NestedNameSpecifier *NNS,
2927                              QualType NamedType) const {
2928  llvm::FoldingSetNodeID ID;
2929  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
2930
2931  void *InsertPos = 0;
2932  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2933  if (T)
2934    return QualType(T, 0);
2935
2936  QualType Canon = NamedType;
2937  if (!Canon.isCanonical()) {
2938    Canon = getCanonicalType(NamedType);
2939    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
2940    assert(!CheckT && "Elaborated canonical type broken");
2941    (void)CheckT;
2942  }
2943
2944  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
2945  Types.push_back(T);
2946  ElaboratedTypes.InsertNode(T, InsertPos);
2947  return QualType(T, 0);
2948}
2949
2950QualType
2951ASTContext::getParenType(QualType InnerType) const {
2952  llvm::FoldingSetNodeID ID;
2953  ParenType::Profile(ID, InnerType);
2954
2955  void *InsertPos = 0;
2956  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2957  if (T)
2958    return QualType(T, 0);
2959
2960  QualType Canon = InnerType;
2961  if (!Canon.isCanonical()) {
2962    Canon = getCanonicalType(InnerType);
2963    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
2964    assert(!CheckT && "Paren canonical type broken");
2965    (void)CheckT;
2966  }
2967
2968  T = new (*this) ParenType(InnerType, Canon);
2969  Types.push_back(T);
2970  ParenTypes.InsertNode(T, InsertPos);
2971  return QualType(T, 0);
2972}
2973
2974QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
2975                                          NestedNameSpecifier *NNS,
2976                                          const IdentifierInfo *Name,
2977                                          QualType Canon) const {
2978  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
2979
2980  if (Canon.isNull()) {
2981    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
2982    ElaboratedTypeKeyword CanonKeyword = Keyword;
2983    if (Keyword == ETK_None)
2984      CanonKeyword = ETK_Typename;
2985
2986    if (CanonNNS != NNS || CanonKeyword != Keyword)
2987      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
2988  }
2989
2990  llvm::FoldingSetNodeID ID;
2991  DependentNameType::Profile(ID, Keyword, NNS, Name);
2992
2993  void *InsertPos = 0;
2994  DependentNameType *T
2995    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
2996  if (T)
2997    return QualType(T, 0);
2998
2999  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
3000  Types.push_back(T);
3001  DependentNameTypes.InsertNode(T, InsertPos);
3002  return QualType(T, 0);
3003}
3004
3005QualType
3006ASTContext::getDependentTemplateSpecializationType(
3007                                 ElaboratedTypeKeyword Keyword,
3008                                 NestedNameSpecifier *NNS,
3009                                 const IdentifierInfo *Name,
3010                                 const TemplateArgumentListInfo &Args) const {
3011  // TODO: avoid this copy
3012  SmallVector<TemplateArgument, 16> ArgCopy;
3013  for (unsigned I = 0, E = Args.size(); I != E; ++I)
3014    ArgCopy.push_back(Args[I].getArgument());
3015  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
3016                                                ArgCopy.size(),
3017                                                ArgCopy.data());
3018}
3019
3020QualType
3021ASTContext::getDependentTemplateSpecializationType(
3022                                 ElaboratedTypeKeyword Keyword,
3023                                 NestedNameSpecifier *NNS,
3024                                 const IdentifierInfo *Name,
3025                                 unsigned NumArgs,
3026                                 const TemplateArgument *Args) const {
3027  assert((!NNS || NNS->isDependent()) &&
3028         "nested-name-specifier must be dependent");
3029
3030  llvm::FoldingSetNodeID ID;
3031  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
3032                                               Name, NumArgs, Args);
3033
3034  void *InsertPos = 0;
3035  DependentTemplateSpecializationType *T
3036    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3037  if (T)
3038    return QualType(T, 0);
3039
3040  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
3041
3042  ElaboratedTypeKeyword CanonKeyword = Keyword;
3043  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
3044
3045  bool AnyNonCanonArgs = false;
3046  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
3047  for (unsigned I = 0; I != NumArgs; ++I) {
3048    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
3049    if (!CanonArgs[I].structurallyEquals(Args[I]))
3050      AnyNonCanonArgs = true;
3051  }
3052
3053  QualType Canon;
3054  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
3055    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
3056                                                   Name, NumArgs,
3057                                                   CanonArgs.data());
3058
3059    // Find the insert position again.
3060    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3061  }
3062
3063  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
3064                        sizeof(TemplateArgument) * NumArgs),
3065                       TypeAlignment);
3066  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
3067                                                    Name, NumArgs, Args, Canon);
3068  Types.push_back(T);
3069  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
3070  return QualType(T, 0);
3071}
3072
3073QualType ASTContext::getPackExpansionType(QualType Pattern,
3074                                      llvm::Optional<unsigned> NumExpansions) {
3075  llvm::FoldingSetNodeID ID;
3076  PackExpansionType::Profile(ID, Pattern, NumExpansions);
3077
3078  assert(Pattern->containsUnexpandedParameterPack() &&
3079         "Pack expansions must expand one or more parameter packs");
3080  void *InsertPos = 0;
3081  PackExpansionType *T
3082    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3083  if (T)
3084    return QualType(T, 0);
3085
3086  QualType Canon;
3087  if (!Pattern.isCanonical()) {
3088    Canon = getCanonicalType(Pattern);
3089    // The canonical type might not contain an unexpanded parameter pack, if it
3090    // contains an alias template specialization which ignores one of its
3091    // parameters.
3092    if (Canon->containsUnexpandedParameterPack()) {
3093      Canon = getPackExpansionType(getCanonicalType(Pattern), NumExpansions);
3094
3095      // Find the insert position again, in case we inserted an element into
3096      // PackExpansionTypes and invalidated our insert position.
3097      PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3098    }
3099  }
3100
3101  T = new (*this) PackExpansionType(Pattern, Canon, NumExpansions);
3102  Types.push_back(T);
3103  PackExpansionTypes.InsertNode(T, InsertPos);
3104  return QualType(T, 0);
3105}
3106
3107/// CmpProtocolNames - Comparison predicate for sorting protocols
3108/// alphabetically.
3109static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
3110                            const ObjCProtocolDecl *RHS) {
3111  return LHS->getDeclName() < RHS->getDeclName();
3112}
3113
3114static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
3115                                unsigned NumProtocols) {
3116  if (NumProtocols == 0) return true;
3117
3118  if (Protocols[0]->getCanonicalDecl() != Protocols[0])
3119    return false;
3120
3121  for (unsigned i = 1; i != NumProtocols; ++i)
3122    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]) ||
3123        Protocols[i]->getCanonicalDecl() != Protocols[i])
3124      return false;
3125  return true;
3126}
3127
3128static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
3129                                   unsigned &NumProtocols) {
3130  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
3131
3132  // Sort protocols, keyed by name.
3133  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
3134
3135  // Canonicalize.
3136  for (unsigned I = 0, N = NumProtocols; I != N; ++I)
3137    Protocols[I] = Protocols[I]->getCanonicalDecl();
3138
3139  // Remove duplicates.
3140  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
3141  NumProtocols = ProtocolsEnd-Protocols;
3142}
3143
3144QualType ASTContext::getObjCObjectType(QualType BaseType,
3145                                       ObjCProtocolDecl * const *Protocols,
3146                                       unsigned NumProtocols) const {
3147  // If the base type is an interface and there aren't any protocols
3148  // to add, then the interface type will do just fine.
3149  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
3150    return BaseType;
3151
3152  // Look in the folding set for an existing type.
3153  llvm::FoldingSetNodeID ID;
3154  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
3155  void *InsertPos = 0;
3156  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
3157    return QualType(QT, 0);
3158
3159  // Build the canonical type, which has the canonical base type and
3160  // a sorted-and-uniqued list of protocols.
3161  QualType Canonical;
3162  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
3163  if (!ProtocolsSorted || !BaseType.isCanonical()) {
3164    if (!ProtocolsSorted) {
3165      SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
3166                                                     Protocols + NumProtocols);
3167      unsigned UniqueCount = NumProtocols;
3168
3169      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
3170      Canonical = getObjCObjectType(getCanonicalType(BaseType),
3171                                    &Sorted[0], UniqueCount);
3172    } else {
3173      Canonical = getObjCObjectType(getCanonicalType(BaseType),
3174                                    Protocols, NumProtocols);
3175    }
3176
3177    // Regenerate InsertPos.
3178    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
3179  }
3180
3181  unsigned Size = sizeof(ObjCObjectTypeImpl);
3182  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
3183  void *Mem = Allocate(Size, TypeAlignment);
3184  ObjCObjectTypeImpl *T =
3185    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
3186
3187  Types.push_back(T);
3188  ObjCObjectTypes.InsertNode(T, InsertPos);
3189  return QualType(T, 0);
3190}
3191
3192/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
3193/// the given object type.
3194QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
3195  llvm::FoldingSetNodeID ID;
3196  ObjCObjectPointerType::Profile(ID, ObjectT);
3197
3198  void *InsertPos = 0;
3199  if (ObjCObjectPointerType *QT =
3200              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
3201    return QualType(QT, 0);
3202
3203  // Find the canonical object type.
3204  QualType Canonical;
3205  if (!ObjectT.isCanonical()) {
3206    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
3207
3208    // Regenerate InsertPos.
3209    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
3210  }
3211
3212  // No match.
3213  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
3214  ObjCObjectPointerType *QType =
3215    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
3216
3217  Types.push_back(QType);
3218  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
3219  return QualType(QType, 0);
3220}
3221
3222/// getObjCInterfaceType - Return the unique reference to the type for the
3223/// specified ObjC interface decl. The list of protocols is optional.
3224QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
3225                                          ObjCInterfaceDecl *PrevDecl) const {
3226  if (Decl->TypeForDecl)
3227    return QualType(Decl->TypeForDecl, 0);
3228
3229  if (PrevDecl) {
3230    assert(PrevDecl->TypeForDecl && "previous decl has no TypeForDecl");
3231    Decl->TypeForDecl = PrevDecl->TypeForDecl;
3232    return QualType(PrevDecl->TypeForDecl, 0);
3233  }
3234
3235  // Prefer the definition, if there is one.
3236  if (const ObjCInterfaceDecl *Def = Decl->getDefinition())
3237    Decl = Def;
3238
3239  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
3240  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
3241  Decl->TypeForDecl = T;
3242  Types.push_back(T);
3243  return QualType(T, 0);
3244}
3245
3246/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
3247/// TypeOfExprType AST's (since expression's are never shared). For example,
3248/// multiple declarations that refer to "typeof(x)" all contain different
3249/// DeclRefExpr's. This doesn't effect the type checker, since it operates
3250/// on canonical type's (which are always unique).
3251QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
3252  TypeOfExprType *toe;
3253  if (tofExpr->isTypeDependent()) {
3254    llvm::FoldingSetNodeID ID;
3255    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
3256
3257    void *InsertPos = 0;
3258    DependentTypeOfExprType *Canon
3259      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
3260    if (Canon) {
3261      // We already have a "canonical" version of an identical, dependent
3262      // typeof(expr) type. Use that as our canonical type.
3263      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
3264                                          QualType((TypeOfExprType*)Canon, 0));
3265    } else {
3266      // Build a new, canonical typeof(expr) type.
3267      Canon
3268        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
3269      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
3270      toe = Canon;
3271    }
3272  } else {
3273    QualType Canonical = getCanonicalType(tofExpr->getType());
3274    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
3275  }
3276  Types.push_back(toe);
3277  return QualType(toe, 0);
3278}
3279
3280/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
3281/// TypeOfType AST's. The only motivation to unique these nodes would be
3282/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
3283/// an issue. This doesn't effect the type checker, since it operates
3284/// on canonical type's (which are always unique).
3285QualType ASTContext::getTypeOfType(QualType tofType) const {
3286  QualType Canonical = getCanonicalType(tofType);
3287  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
3288  Types.push_back(tot);
3289  return QualType(tot, 0);
3290}
3291
3292
3293/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
3294/// DecltypeType AST's. The only motivation to unique these nodes would be
3295/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
3296/// an issue. This doesn't effect the type checker, since it operates
3297/// on canonical types (which are always unique).
3298QualType ASTContext::getDecltypeType(Expr *e, QualType UnderlyingType) const {
3299  DecltypeType *dt;
3300
3301  // C++0x [temp.type]p2:
3302  //   If an expression e involves a template parameter, decltype(e) denotes a
3303  //   unique dependent type. Two such decltype-specifiers refer to the same
3304  //   type only if their expressions are equivalent (14.5.6.1).
3305  if (e->isInstantiationDependent()) {
3306    llvm::FoldingSetNodeID ID;
3307    DependentDecltypeType::Profile(ID, *this, e);
3308
3309    void *InsertPos = 0;
3310    DependentDecltypeType *Canon
3311      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
3312    if (Canon) {
3313      // We already have a "canonical" version of an equivalent, dependent
3314      // decltype type. Use that as our canonical type.
3315      dt = new (*this, TypeAlignment) DecltypeType(e, UnderlyingType,
3316                                       QualType((DecltypeType*)Canon, 0));
3317    } else {
3318      // Build a new, canonical typeof(expr) type.
3319      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
3320      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
3321      dt = Canon;
3322    }
3323  } else {
3324    dt = new (*this, TypeAlignment) DecltypeType(e, UnderlyingType,
3325                                      getCanonicalType(UnderlyingType));
3326  }
3327  Types.push_back(dt);
3328  return QualType(dt, 0);
3329}
3330
3331/// getUnaryTransformationType - We don't unique these, since the memory
3332/// savings are minimal and these are rare.
3333QualType ASTContext::getUnaryTransformType(QualType BaseType,
3334                                           QualType UnderlyingType,
3335                                           UnaryTransformType::UTTKind Kind)
3336    const {
3337  UnaryTransformType *Ty =
3338    new (*this, TypeAlignment) UnaryTransformType (BaseType, UnderlyingType,
3339                                                   Kind,
3340                                 UnderlyingType->isDependentType() ?
3341                                 QualType() : getCanonicalType(UnderlyingType));
3342  Types.push_back(Ty);
3343  return QualType(Ty, 0);
3344}
3345
3346/// getAutoType - We only unique auto types after they've been deduced.
3347QualType ASTContext::getAutoType(QualType DeducedType) const {
3348  void *InsertPos = 0;
3349  if (!DeducedType.isNull()) {
3350    // Look in the folding set for an existing type.
3351    llvm::FoldingSetNodeID ID;
3352    AutoType::Profile(ID, DeducedType);
3353    if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
3354      return QualType(AT, 0);
3355  }
3356
3357  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType);
3358  Types.push_back(AT);
3359  if (InsertPos)
3360    AutoTypes.InsertNode(AT, InsertPos);
3361  return QualType(AT, 0);
3362}
3363
3364/// getAtomicType - Return the uniqued reference to the atomic type for
3365/// the given value type.
3366QualType ASTContext::getAtomicType(QualType T) const {
3367  // Unique pointers, to guarantee there is only one pointer of a particular
3368  // structure.
3369  llvm::FoldingSetNodeID ID;
3370  AtomicType::Profile(ID, T);
3371
3372  void *InsertPos = 0;
3373  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
3374    return QualType(AT, 0);
3375
3376  // If the atomic value type isn't canonical, this won't be a canonical type
3377  // either, so fill in the canonical type field.
3378  QualType Canonical;
3379  if (!T.isCanonical()) {
3380    Canonical = getAtomicType(getCanonicalType(T));
3381
3382    // Get the new insert position for the node we care about.
3383    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
3384    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
3385  }
3386  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
3387  Types.push_back(New);
3388  AtomicTypes.InsertNode(New, InsertPos);
3389  return QualType(New, 0);
3390}
3391
3392/// getAutoDeductType - Get type pattern for deducing against 'auto'.
3393QualType ASTContext::getAutoDeductType() const {
3394  if (AutoDeductTy.isNull())
3395    AutoDeductTy = getAutoType(QualType());
3396  assert(!AutoDeductTy.isNull() && "can't build 'auto' pattern");
3397  return AutoDeductTy;
3398}
3399
3400/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
3401QualType ASTContext::getAutoRRefDeductType() const {
3402  if (AutoRRefDeductTy.isNull())
3403    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
3404  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
3405  return AutoRRefDeductTy;
3406}
3407
3408/// getTagDeclType - Return the unique reference to the type for the
3409/// specified TagDecl (struct/union/class/enum) decl.
3410QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
3411  assert (Decl);
3412  // FIXME: What is the design on getTagDeclType when it requires casting
3413  // away const?  mutable?
3414  return getTypeDeclType(const_cast<TagDecl*>(Decl));
3415}
3416
3417/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
3418/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
3419/// needs to agree with the definition in <stddef.h>.
3420CanQualType ASTContext::getSizeType() const {
3421  return getFromTargetType(Target->getSizeType());
3422}
3423
3424/// getIntMaxType - Return the unique type for "intmax_t" (C99 7.18.1.5).
3425CanQualType ASTContext::getIntMaxType() const {
3426  return getFromTargetType(Target->getIntMaxType());
3427}
3428
3429/// getUIntMaxType - Return the unique type for "uintmax_t" (C99 7.18.1.5).
3430CanQualType ASTContext::getUIntMaxType() const {
3431  return getFromTargetType(Target->getUIntMaxType());
3432}
3433
3434/// getSignedWCharType - Return the type of "signed wchar_t".
3435/// Used when in C++, as a GCC extension.
3436QualType ASTContext::getSignedWCharType() const {
3437  // FIXME: derive from "Target" ?
3438  return WCharTy;
3439}
3440
3441/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
3442/// Used when in C++, as a GCC extension.
3443QualType ASTContext::getUnsignedWCharType() const {
3444  // FIXME: derive from "Target" ?
3445  return UnsignedIntTy;
3446}
3447
3448/// getPointerDiffType - Return the unique type for "ptrdiff_t" (C99 7.17)
3449/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
3450QualType ASTContext::getPointerDiffType() const {
3451  return getFromTargetType(Target->getPtrDiffType(0));
3452}
3453
3454//===----------------------------------------------------------------------===//
3455//                              Type Operators
3456//===----------------------------------------------------------------------===//
3457
3458CanQualType ASTContext::getCanonicalParamType(QualType T) const {
3459  // Push qualifiers into arrays, and then discard any remaining
3460  // qualifiers.
3461  T = getCanonicalType(T);
3462  T = getVariableArrayDecayedType(T);
3463  const Type *Ty = T.getTypePtr();
3464  QualType Result;
3465  if (isa<ArrayType>(Ty)) {
3466    Result = getArrayDecayedType(QualType(Ty,0));
3467  } else if (isa<FunctionType>(Ty)) {
3468    Result = getPointerType(QualType(Ty, 0));
3469  } else {
3470    Result = QualType(Ty, 0);
3471  }
3472
3473  return CanQualType::CreateUnsafe(Result);
3474}
3475
3476QualType ASTContext::getUnqualifiedArrayType(QualType type,
3477                                             Qualifiers &quals) {
3478  SplitQualType splitType = type.getSplitUnqualifiedType();
3479
3480  // FIXME: getSplitUnqualifiedType() actually walks all the way to
3481  // the unqualified desugared type and then drops it on the floor.
3482  // We then have to strip that sugar back off with
3483  // getUnqualifiedDesugaredType(), which is silly.
3484  const ArrayType *AT =
3485    dyn_cast<ArrayType>(splitType.Ty->getUnqualifiedDesugaredType());
3486
3487  // If we don't have an array, just use the results in splitType.
3488  if (!AT) {
3489    quals = splitType.Quals;
3490    return QualType(splitType.Ty, 0);
3491  }
3492
3493  // Otherwise, recurse on the array's element type.
3494  QualType elementType = AT->getElementType();
3495  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
3496
3497  // If that didn't change the element type, AT has no qualifiers, so we
3498  // can just use the results in splitType.
3499  if (elementType == unqualElementType) {
3500    assert(quals.empty()); // from the recursive call
3501    quals = splitType.Quals;
3502    return QualType(splitType.Ty, 0);
3503  }
3504
3505  // Otherwise, add in the qualifiers from the outermost type, then
3506  // build the type back up.
3507  quals.addConsistentQualifiers(splitType.Quals);
3508
3509  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
3510    return getConstantArrayType(unqualElementType, CAT->getSize(),
3511                                CAT->getSizeModifier(), 0);
3512  }
3513
3514  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
3515    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
3516  }
3517
3518  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
3519    return getVariableArrayType(unqualElementType,
3520                                VAT->getSizeExpr(),
3521                                VAT->getSizeModifier(),
3522                                VAT->getIndexTypeCVRQualifiers(),
3523                                VAT->getBracketsRange());
3524  }
3525
3526  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
3527  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
3528                                    DSAT->getSizeModifier(), 0,
3529                                    SourceRange());
3530}
3531
3532/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
3533/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
3534/// they point to and return true. If T1 and T2 aren't pointer types
3535/// or pointer-to-member types, or if they are not similar at this
3536/// level, returns false and leaves T1 and T2 unchanged. Top-level
3537/// qualifiers on T1 and T2 are ignored. This function will typically
3538/// be called in a loop that successively "unwraps" pointer and
3539/// pointer-to-member types to compare them at each level.
3540bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
3541  const PointerType *T1PtrType = T1->getAs<PointerType>(),
3542                    *T2PtrType = T2->getAs<PointerType>();
3543  if (T1PtrType && T2PtrType) {
3544    T1 = T1PtrType->getPointeeType();
3545    T2 = T2PtrType->getPointeeType();
3546    return true;
3547  }
3548
3549  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
3550                          *T2MPType = T2->getAs<MemberPointerType>();
3551  if (T1MPType && T2MPType &&
3552      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
3553                             QualType(T2MPType->getClass(), 0))) {
3554    T1 = T1MPType->getPointeeType();
3555    T2 = T2MPType->getPointeeType();
3556    return true;
3557  }
3558
3559  if (getLangOpts().ObjC1) {
3560    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
3561                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
3562    if (T1OPType && T2OPType) {
3563      T1 = T1OPType->getPointeeType();
3564      T2 = T2OPType->getPointeeType();
3565      return true;
3566    }
3567  }
3568
3569  // FIXME: Block pointers, too?
3570
3571  return false;
3572}
3573
3574DeclarationNameInfo
3575ASTContext::getNameForTemplate(TemplateName Name,
3576                               SourceLocation NameLoc) const {
3577  switch (Name.getKind()) {
3578  case TemplateName::QualifiedTemplate:
3579  case TemplateName::Template:
3580    // DNInfo work in progress: CHECKME: what about DNLoc?
3581    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
3582                               NameLoc);
3583
3584  case TemplateName::OverloadedTemplate: {
3585    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
3586    // DNInfo work in progress: CHECKME: what about DNLoc?
3587    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
3588  }
3589
3590  case TemplateName::DependentTemplate: {
3591    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3592    DeclarationName DName;
3593    if (DTN->isIdentifier()) {
3594      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
3595      return DeclarationNameInfo(DName, NameLoc);
3596    } else {
3597      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
3598      // DNInfo work in progress: FIXME: source locations?
3599      DeclarationNameLoc DNLoc;
3600      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
3601      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
3602      return DeclarationNameInfo(DName, NameLoc, DNLoc);
3603    }
3604  }
3605
3606  case TemplateName::SubstTemplateTemplateParm: {
3607    SubstTemplateTemplateParmStorage *subst
3608      = Name.getAsSubstTemplateTemplateParm();
3609    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
3610                               NameLoc);
3611  }
3612
3613  case TemplateName::SubstTemplateTemplateParmPack: {
3614    SubstTemplateTemplateParmPackStorage *subst
3615      = Name.getAsSubstTemplateTemplateParmPack();
3616    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
3617                               NameLoc);
3618  }
3619  }
3620
3621  llvm_unreachable("bad template name kind!");
3622}
3623
3624TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
3625  switch (Name.getKind()) {
3626  case TemplateName::QualifiedTemplate:
3627  case TemplateName::Template: {
3628    TemplateDecl *Template = Name.getAsTemplateDecl();
3629    if (TemplateTemplateParmDecl *TTP
3630          = dyn_cast<TemplateTemplateParmDecl>(Template))
3631      Template = getCanonicalTemplateTemplateParmDecl(TTP);
3632
3633    // The canonical template name is the canonical template declaration.
3634    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
3635  }
3636
3637  case TemplateName::OverloadedTemplate:
3638    llvm_unreachable("cannot canonicalize overloaded template");
3639
3640  case TemplateName::DependentTemplate: {
3641    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3642    assert(DTN && "Non-dependent template names must refer to template decls.");
3643    return DTN->CanonicalTemplateName;
3644  }
3645
3646  case TemplateName::SubstTemplateTemplateParm: {
3647    SubstTemplateTemplateParmStorage *subst
3648      = Name.getAsSubstTemplateTemplateParm();
3649    return getCanonicalTemplateName(subst->getReplacement());
3650  }
3651
3652  case TemplateName::SubstTemplateTemplateParmPack: {
3653    SubstTemplateTemplateParmPackStorage *subst
3654                                  = Name.getAsSubstTemplateTemplateParmPack();
3655    TemplateTemplateParmDecl *canonParameter
3656      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
3657    TemplateArgument canonArgPack
3658      = getCanonicalTemplateArgument(subst->getArgumentPack());
3659    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
3660  }
3661  }
3662
3663  llvm_unreachable("bad template name!");
3664}
3665
3666bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
3667  X = getCanonicalTemplateName(X);
3668  Y = getCanonicalTemplateName(Y);
3669  return X.getAsVoidPointer() == Y.getAsVoidPointer();
3670}
3671
3672TemplateArgument
3673ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
3674  switch (Arg.getKind()) {
3675    case TemplateArgument::Null:
3676      return Arg;
3677
3678    case TemplateArgument::Expression:
3679      return Arg;
3680
3681    case TemplateArgument::Declaration: {
3682      if (Decl *D = Arg.getAsDecl())
3683          return TemplateArgument(D->getCanonicalDecl());
3684      return TemplateArgument((Decl*)0);
3685    }
3686
3687    case TemplateArgument::Template:
3688      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
3689
3690    case TemplateArgument::TemplateExpansion:
3691      return TemplateArgument(getCanonicalTemplateName(
3692                                         Arg.getAsTemplateOrTemplatePattern()),
3693                              Arg.getNumTemplateExpansions());
3694
3695    case TemplateArgument::Integral:
3696      return TemplateArgument(Arg, getCanonicalType(Arg.getIntegralType()));
3697
3698    case TemplateArgument::Type:
3699      return TemplateArgument(getCanonicalType(Arg.getAsType()));
3700
3701    case TemplateArgument::Pack: {
3702      if (Arg.pack_size() == 0)
3703        return Arg;
3704
3705      TemplateArgument *CanonArgs
3706        = new (*this) TemplateArgument[Arg.pack_size()];
3707      unsigned Idx = 0;
3708      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
3709                                        AEnd = Arg.pack_end();
3710           A != AEnd; (void)++A, ++Idx)
3711        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
3712
3713      return TemplateArgument(CanonArgs, Arg.pack_size());
3714    }
3715  }
3716
3717  // Silence GCC warning
3718  llvm_unreachable("Unhandled template argument kind");
3719}
3720
3721NestedNameSpecifier *
3722ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
3723  if (!NNS)
3724    return 0;
3725
3726  switch (NNS->getKind()) {
3727  case NestedNameSpecifier::Identifier:
3728    // Canonicalize the prefix but keep the identifier the same.
3729    return NestedNameSpecifier::Create(*this,
3730                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
3731                                       NNS->getAsIdentifier());
3732
3733  case NestedNameSpecifier::Namespace:
3734    // A namespace is canonical; build a nested-name-specifier with
3735    // this namespace and no prefix.
3736    return NestedNameSpecifier::Create(*this, 0,
3737                                 NNS->getAsNamespace()->getOriginalNamespace());
3738
3739  case NestedNameSpecifier::NamespaceAlias:
3740    // A namespace is canonical; build a nested-name-specifier with
3741    // this namespace and no prefix.
3742    return NestedNameSpecifier::Create(*this, 0,
3743                                    NNS->getAsNamespaceAlias()->getNamespace()
3744                                                      ->getOriginalNamespace());
3745
3746  case NestedNameSpecifier::TypeSpec:
3747  case NestedNameSpecifier::TypeSpecWithTemplate: {
3748    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
3749
3750    // If we have some kind of dependent-named type (e.g., "typename T::type"),
3751    // break it apart into its prefix and identifier, then reconsititute those
3752    // as the canonical nested-name-specifier. This is required to canonicalize
3753    // a dependent nested-name-specifier involving typedefs of dependent-name
3754    // types, e.g.,
3755    //   typedef typename T::type T1;
3756    //   typedef typename T1::type T2;
3757    if (const DependentNameType *DNT = T->getAs<DependentNameType>())
3758      return NestedNameSpecifier::Create(*this, DNT->getQualifier(),
3759                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
3760
3761    // Otherwise, just canonicalize the type, and force it to be a TypeSpec.
3762    // FIXME: Why are TypeSpec and TypeSpecWithTemplate distinct in the
3763    // first place?
3764    return NestedNameSpecifier::Create(*this, 0, false,
3765                                       const_cast<Type*>(T.getTypePtr()));
3766  }
3767
3768  case NestedNameSpecifier::Global:
3769    // The global specifier is canonical and unique.
3770    return NNS;
3771  }
3772
3773  llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
3774}
3775
3776
3777const ArrayType *ASTContext::getAsArrayType(QualType T) const {
3778  // Handle the non-qualified case efficiently.
3779  if (!T.hasLocalQualifiers()) {
3780    // Handle the common positive case fast.
3781    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
3782      return AT;
3783  }
3784
3785  // Handle the common negative case fast.
3786  if (!isa<ArrayType>(T.getCanonicalType()))
3787    return 0;
3788
3789  // Apply any qualifiers from the array type to the element type.  This
3790  // implements C99 6.7.3p8: "If the specification of an array type includes
3791  // any type qualifiers, the element type is so qualified, not the array type."
3792
3793  // If we get here, we either have type qualifiers on the type, or we have
3794  // sugar such as a typedef in the way.  If we have type qualifiers on the type
3795  // we must propagate them down into the element type.
3796
3797  SplitQualType split = T.getSplitDesugaredType();
3798  Qualifiers qs = split.Quals;
3799
3800  // If we have a simple case, just return now.
3801  const ArrayType *ATy = dyn_cast<ArrayType>(split.Ty);
3802  if (ATy == 0 || qs.empty())
3803    return ATy;
3804
3805  // Otherwise, we have an array and we have qualifiers on it.  Push the
3806  // qualifiers into the array element type and return a new array type.
3807  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
3808
3809  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
3810    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
3811                                                CAT->getSizeModifier(),
3812                                           CAT->getIndexTypeCVRQualifiers()));
3813  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
3814    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
3815                                                  IAT->getSizeModifier(),
3816                                           IAT->getIndexTypeCVRQualifiers()));
3817
3818  if (const DependentSizedArrayType *DSAT
3819        = dyn_cast<DependentSizedArrayType>(ATy))
3820    return cast<ArrayType>(
3821                     getDependentSizedArrayType(NewEltTy,
3822                                                DSAT->getSizeExpr(),
3823                                                DSAT->getSizeModifier(),
3824                                              DSAT->getIndexTypeCVRQualifiers(),
3825                                                DSAT->getBracketsRange()));
3826
3827  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
3828  return cast<ArrayType>(getVariableArrayType(NewEltTy,
3829                                              VAT->getSizeExpr(),
3830                                              VAT->getSizeModifier(),
3831                                              VAT->getIndexTypeCVRQualifiers(),
3832                                              VAT->getBracketsRange()));
3833}
3834
3835QualType ASTContext::getAdjustedParameterType(QualType T) const {
3836  // C99 6.7.5.3p7:
3837  //   A declaration of a parameter as "array of type" shall be
3838  //   adjusted to "qualified pointer to type", where the type
3839  //   qualifiers (if any) are those specified within the [ and ] of
3840  //   the array type derivation.
3841  if (T->isArrayType())
3842    return getArrayDecayedType(T);
3843
3844  // C99 6.7.5.3p8:
3845  //   A declaration of a parameter as "function returning type"
3846  //   shall be adjusted to "pointer to function returning type", as
3847  //   in 6.3.2.1.
3848  if (T->isFunctionType())
3849    return getPointerType(T);
3850
3851  return T;
3852}
3853
3854QualType ASTContext::getSignatureParameterType(QualType T) const {
3855  T = getVariableArrayDecayedType(T);
3856  T = getAdjustedParameterType(T);
3857  return T.getUnqualifiedType();
3858}
3859
3860/// getArrayDecayedType - Return the properly qualified result of decaying the
3861/// specified array type to a pointer.  This operation is non-trivial when
3862/// handling typedefs etc.  The canonical type of "T" must be an array type,
3863/// this returns a pointer to a properly qualified element of the array.
3864///
3865/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
3866QualType ASTContext::getArrayDecayedType(QualType Ty) const {
3867  // Get the element type with 'getAsArrayType' so that we don't lose any
3868  // typedefs in the element type of the array.  This also handles propagation
3869  // of type qualifiers from the array type into the element type if present
3870  // (C99 6.7.3p8).
3871  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
3872  assert(PrettyArrayType && "Not an array type!");
3873
3874  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
3875
3876  // int x[restrict 4] ->  int *restrict
3877  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
3878}
3879
3880QualType ASTContext::getBaseElementType(const ArrayType *array) const {
3881  return getBaseElementType(array->getElementType());
3882}
3883
3884QualType ASTContext::getBaseElementType(QualType type) const {
3885  Qualifiers qs;
3886  while (true) {
3887    SplitQualType split = type.getSplitDesugaredType();
3888    const ArrayType *array = split.Ty->getAsArrayTypeUnsafe();
3889    if (!array) break;
3890
3891    type = array->getElementType();
3892    qs.addConsistentQualifiers(split.Quals);
3893  }
3894
3895  return getQualifiedType(type, qs);
3896}
3897
3898/// getConstantArrayElementCount - Returns number of constant array elements.
3899uint64_t
3900ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
3901  uint64_t ElementCount = 1;
3902  do {
3903    ElementCount *= CA->getSize().getZExtValue();
3904    CA = dyn_cast<ConstantArrayType>(CA->getElementType());
3905  } while (CA);
3906  return ElementCount;
3907}
3908
3909/// getFloatingRank - Return a relative rank for floating point types.
3910/// This routine will assert if passed a built-in type that isn't a float.
3911static FloatingRank getFloatingRank(QualType T) {
3912  if (const ComplexType *CT = T->getAs<ComplexType>())
3913    return getFloatingRank(CT->getElementType());
3914
3915  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
3916  switch (T->getAs<BuiltinType>()->getKind()) {
3917  default: llvm_unreachable("getFloatingRank(): not a floating type");
3918  case BuiltinType::Half:       return HalfRank;
3919  case BuiltinType::Float:      return FloatRank;
3920  case BuiltinType::Double:     return DoubleRank;
3921  case BuiltinType::LongDouble: return LongDoubleRank;
3922  }
3923}
3924
3925/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
3926/// point or a complex type (based on typeDomain/typeSize).
3927/// 'typeDomain' is a real floating point or complex type.
3928/// 'typeSize' is a real floating point or complex type.
3929QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
3930                                                       QualType Domain) const {
3931  FloatingRank EltRank = getFloatingRank(Size);
3932  if (Domain->isComplexType()) {
3933    switch (EltRank) {
3934    case HalfRank: llvm_unreachable("Complex half is not supported");
3935    case FloatRank:      return FloatComplexTy;
3936    case DoubleRank:     return DoubleComplexTy;
3937    case LongDoubleRank: return LongDoubleComplexTy;
3938    }
3939  }
3940
3941  assert(Domain->isRealFloatingType() && "Unknown domain!");
3942  switch (EltRank) {
3943  case HalfRank: llvm_unreachable("Half ranks are not valid here");
3944  case FloatRank:      return FloatTy;
3945  case DoubleRank:     return DoubleTy;
3946  case LongDoubleRank: return LongDoubleTy;
3947  }
3948  llvm_unreachable("getFloatingRank(): illegal value for rank");
3949}
3950
3951/// getFloatingTypeOrder - Compare the rank of the two specified floating
3952/// point types, ignoring the domain of the type (i.e. 'double' ==
3953/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
3954/// LHS < RHS, return -1.
3955int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
3956  FloatingRank LHSR = getFloatingRank(LHS);
3957  FloatingRank RHSR = getFloatingRank(RHS);
3958
3959  if (LHSR == RHSR)
3960    return 0;
3961  if (LHSR > RHSR)
3962    return 1;
3963  return -1;
3964}
3965
3966/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
3967/// routine will assert if passed a built-in type that isn't an integer or enum,
3968/// or if it is not canonicalized.
3969unsigned ASTContext::getIntegerRank(const Type *T) const {
3970  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
3971
3972  switch (cast<BuiltinType>(T)->getKind()) {
3973  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
3974  case BuiltinType::Bool:
3975    return 1 + (getIntWidth(BoolTy) << 3);
3976  case BuiltinType::Char_S:
3977  case BuiltinType::Char_U:
3978  case BuiltinType::SChar:
3979  case BuiltinType::UChar:
3980    return 2 + (getIntWidth(CharTy) << 3);
3981  case BuiltinType::Short:
3982  case BuiltinType::UShort:
3983    return 3 + (getIntWidth(ShortTy) << 3);
3984  case BuiltinType::Int:
3985  case BuiltinType::UInt:
3986    return 4 + (getIntWidth(IntTy) << 3);
3987  case BuiltinType::Long:
3988  case BuiltinType::ULong:
3989    return 5 + (getIntWidth(LongTy) << 3);
3990  case BuiltinType::LongLong:
3991  case BuiltinType::ULongLong:
3992    return 6 + (getIntWidth(LongLongTy) << 3);
3993  case BuiltinType::Int128:
3994  case BuiltinType::UInt128:
3995    return 7 + (getIntWidth(Int128Ty) << 3);
3996  }
3997}
3998
3999/// \brief Whether this is a promotable bitfield reference according
4000/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
4001///
4002/// \returns the type this bit-field will promote to, or NULL if no
4003/// promotion occurs.
4004QualType ASTContext::isPromotableBitField(Expr *E) const {
4005  if (E->isTypeDependent() || E->isValueDependent())
4006    return QualType();
4007
4008  FieldDecl *Field = E->getBitField();
4009  if (!Field)
4010    return QualType();
4011
4012  QualType FT = Field->getType();
4013
4014  uint64_t BitWidth = Field->getBitWidthValue(*this);
4015  uint64_t IntSize = getTypeSize(IntTy);
4016  // GCC extension compatibility: if the bit-field size is less than or equal
4017  // to the size of int, it gets promoted no matter what its type is.
4018  // For instance, unsigned long bf : 4 gets promoted to signed int.
4019  if (BitWidth < IntSize)
4020    return IntTy;
4021
4022  if (BitWidth == IntSize)
4023    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
4024
4025  // Types bigger than int are not subject to promotions, and therefore act
4026  // like the base type.
4027  // FIXME: This doesn't quite match what gcc does, but what gcc does here
4028  // is ridiculous.
4029  return QualType();
4030}
4031
4032/// getPromotedIntegerType - Returns the type that Promotable will
4033/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
4034/// integer type.
4035QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
4036  assert(!Promotable.isNull());
4037  assert(Promotable->isPromotableIntegerType());
4038  if (const EnumType *ET = Promotable->getAs<EnumType>())
4039    return ET->getDecl()->getPromotionType();
4040
4041  if (const BuiltinType *BT = Promotable->getAs<BuiltinType>()) {
4042    // C++ [conv.prom]: A prvalue of type char16_t, char32_t, or wchar_t
4043    // (3.9.1) can be converted to a prvalue of the first of the following
4044    // types that can represent all the values of its underlying type:
4045    // int, unsigned int, long int, unsigned long int, long long int, or
4046    // unsigned long long int [...]
4047    // FIXME: Is there some better way to compute this?
4048    if (BT->getKind() == BuiltinType::WChar_S ||
4049        BT->getKind() == BuiltinType::WChar_U ||
4050        BT->getKind() == BuiltinType::Char16 ||
4051        BT->getKind() == BuiltinType::Char32) {
4052      bool FromIsSigned = BT->getKind() == BuiltinType::WChar_S;
4053      uint64_t FromSize = getTypeSize(BT);
4054      QualType PromoteTypes[] = { IntTy, UnsignedIntTy, LongTy, UnsignedLongTy,
4055                                  LongLongTy, UnsignedLongLongTy };
4056      for (size_t Idx = 0; Idx < llvm::array_lengthof(PromoteTypes); ++Idx) {
4057        uint64_t ToSize = getTypeSize(PromoteTypes[Idx]);
4058        if (FromSize < ToSize ||
4059            (FromSize == ToSize &&
4060             FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType()))
4061          return PromoteTypes[Idx];
4062      }
4063      llvm_unreachable("char type should fit into long long");
4064    }
4065  }
4066
4067  // At this point, we should have a signed or unsigned integer type.
4068  if (Promotable->isSignedIntegerType())
4069    return IntTy;
4070  uint64_t PromotableSize = getTypeSize(Promotable);
4071  uint64_t IntSize = getTypeSize(IntTy);
4072  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
4073  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
4074}
4075
4076/// \brief Recurses in pointer/array types until it finds an objc retainable
4077/// type and returns its ownership.
4078Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
4079  while (!T.isNull()) {
4080    if (T.getObjCLifetime() != Qualifiers::OCL_None)
4081      return T.getObjCLifetime();
4082    if (T->isArrayType())
4083      T = getBaseElementType(T);
4084    else if (const PointerType *PT = T->getAs<PointerType>())
4085      T = PT->getPointeeType();
4086    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4087      T = RT->getPointeeType();
4088    else
4089      break;
4090  }
4091
4092  return Qualifiers::OCL_None;
4093}
4094
4095/// getIntegerTypeOrder - Returns the highest ranked integer type:
4096/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
4097/// LHS < RHS, return -1.
4098int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
4099  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
4100  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
4101  if (LHSC == RHSC) return 0;
4102
4103  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
4104  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
4105
4106  unsigned LHSRank = getIntegerRank(LHSC);
4107  unsigned RHSRank = getIntegerRank(RHSC);
4108
4109  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
4110    if (LHSRank == RHSRank) return 0;
4111    return LHSRank > RHSRank ? 1 : -1;
4112  }
4113
4114  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
4115  if (LHSUnsigned) {
4116    // If the unsigned [LHS] type is larger, return it.
4117    if (LHSRank >= RHSRank)
4118      return 1;
4119
4120    // If the signed type can represent all values of the unsigned type, it
4121    // wins.  Because we are dealing with 2's complement and types that are
4122    // powers of two larger than each other, this is always safe.
4123    return -1;
4124  }
4125
4126  // If the unsigned [RHS] type is larger, return it.
4127  if (RHSRank >= LHSRank)
4128    return -1;
4129
4130  // If the signed type can represent all values of the unsigned type, it
4131  // wins.  Because we are dealing with 2's complement and types that are
4132  // powers of two larger than each other, this is always safe.
4133  return 1;
4134}
4135
4136static RecordDecl *
4137CreateRecordDecl(const ASTContext &Ctx, RecordDecl::TagKind TK,
4138                 DeclContext *DC, IdentifierInfo *Id) {
4139  SourceLocation Loc;
4140  if (Ctx.getLangOpts().CPlusPlus)
4141    return CXXRecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
4142  else
4143    return RecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
4144}
4145
4146// getCFConstantStringType - Return the type used for constant CFStrings.
4147QualType ASTContext::getCFConstantStringType() const {
4148  if (!CFConstantStringTypeDecl) {
4149    CFConstantStringTypeDecl =
4150      CreateRecordDecl(*this, TTK_Struct, TUDecl,
4151                       &Idents.get("NSConstantString"));
4152    CFConstantStringTypeDecl->startDefinition();
4153
4154    QualType FieldTypes[4];
4155
4156    // const int *isa;
4157    FieldTypes[0] = getPointerType(IntTy.withConst());
4158    // int flags;
4159    FieldTypes[1] = IntTy;
4160    // const char *str;
4161    FieldTypes[2] = getPointerType(CharTy.withConst());
4162    // long length;
4163    FieldTypes[3] = LongTy;
4164
4165    // Create fields
4166    for (unsigned i = 0; i < 4; ++i) {
4167      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
4168                                           SourceLocation(),
4169                                           SourceLocation(), 0,
4170                                           FieldTypes[i], /*TInfo=*/0,
4171                                           /*BitWidth=*/0,
4172                                           /*Mutable=*/false,
4173                                           ICIS_NoInit);
4174      Field->setAccess(AS_public);
4175      CFConstantStringTypeDecl->addDecl(Field);
4176    }
4177
4178    CFConstantStringTypeDecl->completeDefinition();
4179  }
4180
4181  return getTagDeclType(CFConstantStringTypeDecl);
4182}
4183
4184void ASTContext::setCFConstantStringType(QualType T) {
4185  const RecordType *Rec = T->getAs<RecordType>();
4186  assert(Rec && "Invalid CFConstantStringType");
4187  CFConstantStringTypeDecl = Rec->getDecl();
4188}
4189
4190QualType ASTContext::getBlockDescriptorType() const {
4191  if (BlockDescriptorType)
4192    return getTagDeclType(BlockDescriptorType);
4193
4194  RecordDecl *T;
4195  // FIXME: Needs the FlagAppleBlock bit.
4196  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
4197                       &Idents.get("__block_descriptor"));
4198  T->startDefinition();
4199
4200  QualType FieldTypes[] = {
4201    UnsignedLongTy,
4202    UnsignedLongTy,
4203  };
4204
4205  const char *FieldNames[] = {
4206    "reserved",
4207    "Size"
4208  };
4209
4210  for (size_t i = 0; i < 2; ++i) {
4211    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
4212                                         SourceLocation(),
4213                                         &Idents.get(FieldNames[i]),
4214                                         FieldTypes[i], /*TInfo=*/0,
4215                                         /*BitWidth=*/0,
4216                                         /*Mutable=*/false,
4217                                         ICIS_NoInit);
4218    Field->setAccess(AS_public);
4219    T->addDecl(Field);
4220  }
4221
4222  T->completeDefinition();
4223
4224  BlockDescriptorType = T;
4225
4226  return getTagDeclType(BlockDescriptorType);
4227}
4228
4229QualType ASTContext::getBlockDescriptorExtendedType() const {
4230  if (BlockDescriptorExtendedType)
4231    return getTagDeclType(BlockDescriptorExtendedType);
4232
4233  RecordDecl *T;
4234  // FIXME: Needs the FlagAppleBlock bit.
4235  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
4236                       &Idents.get("__block_descriptor_withcopydispose"));
4237  T->startDefinition();
4238
4239  QualType FieldTypes[] = {
4240    UnsignedLongTy,
4241    UnsignedLongTy,
4242    getPointerType(VoidPtrTy),
4243    getPointerType(VoidPtrTy)
4244  };
4245
4246  const char *FieldNames[] = {
4247    "reserved",
4248    "Size",
4249    "CopyFuncPtr",
4250    "DestroyFuncPtr"
4251  };
4252
4253  for (size_t i = 0; i < 4; ++i) {
4254    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
4255                                         SourceLocation(),
4256                                         &Idents.get(FieldNames[i]),
4257                                         FieldTypes[i], /*TInfo=*/0,
4258                                         /*BitWidth=*/0,
4259                                         /*Mutable=*/false,
4260                                         ICIS_NoInit);
4261    Field->setAccess(AS_public);
4262    T->addDecl(Field);
4263  }
4264
4265  T->completeDefinition();
4266
4267  BlockDescriptorExtendedType = T;
4268
4269  return getTagDeclType(BlockDescriptorExtendedType);
4270}
4271
4272bool ASTContext::BlockRequiresCopying(QualType Ty) const {
4273  if (Ty->isObjCRetainableType())
4274    return true;
4275  if (getLangOpts().CPlusPlus) {
4276    if (const RecordType *RT = Ty->getAs<RecordType>()) {
4277      CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
4278      return RD->hasConstCopyConstructor();
4279
4280    }
4281  }
4282  return false;
4283}
4284
4285QualType
4286ASTContext::BuildByRefType(StringRef DeclName, QualType Ty) const {
4287  //  type = struct __Block_byref_1_X {
4288  //    void *__isa;
4289  //    struct __Block_byref_1_X *__forwarding;
4290  //    unsigned int __flags;
4291  //    unsigned int __size;
4292  //    void *__copy_helper;            // as needed
4293  //    void *__destroy_help            // as needed
4294  //    int X;
4295  //  } *
4296
4297  bool HasCopyAndDispose = BlockRequiresCopying(Ty);
4298
4299  // FIXME: Move up
4300  SmallString<36> Name;
4301  llvm::raw_svector_ostream(Name) << "__Block_byref_" <<
4302                                  ++UniqueBlockByRefTypeID << '_' << DeclName;
4303  RecordDecl *T;
4304  T = CreateRecordDecl(*this, TTK_Struct, TUDecl, &Idents.get(Name.str()));
4305  T->startDefinition();
4306  QualType Int32Ty = IntTy;
4307  assert(getIntWidth(IntTy) == 32 && "non-32bit int not supported");
4308  QualType FieldTypes[] = {
4309    getPointerType(VoidPtrTy),
4310    getPointerType(getTagDeclType(T)),
4311    Int32Ty,
4312    Int32Ty,
4313    getPointerType(VoidPtrTy),
4314    getPointerType(VoidPtrTy),
4315    Ty
4316  };
4317
4318  StringRef FieldNames[] = {
4319    "__isa",
4320    "__forwarding",
4321    "__flags",
4322    "__size",
4323    "__copy_helper",
4324    "__destroy_helper",
4325    DeclName,
4326  };
4327
4328  for (size_t i = 0; i < 7; ++i) {
4329    if (!HasCopyAndDispose && i >=4 && i <= 5)
4330      continue;
4331    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
4332                                         SourceLocation(),
4333                                         &Idents.get(FieldNames[i]),
4334                                         FieldTypes[i], /*TInfo=*/0,
4335                                         /*BitWidth=*/0, /*Mutable=*/false,
4336                                         ICIS_NoInit);
4337    Field->setAccess(AS_public);
4338    T->addDecl(Field);
4339  }
4340
4341  T->completeDefinition();
4342
4343  return getPointerType(getTagDeclType(T));
4344}
4345
4346TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
4347  if (!ObjCInstanceTypeDecl)
4348    ObjCInstanceTypeDecl = TypedefDecl::Create(*this,
4349                                               getTranslationUnitDecl(),
4350                                               SourceLocation(),
4351                                               SourceLocation(),
4352                                               &Idents.get("instancetype"),
4353                                     getTrivialTypeSourceInfo(getObjCIdType()));
4354  return ObjCInstanceTypeDecl;
4355}
4356
4357// This returns true if a type has been typedefed to BOOL:
4358// typedef <type> BOOL;
4359static bool isTypeTypedefedAsBOOL(QualType T) {
4360  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
4361    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
4362      return II->isStr("BOOL");
4363
4364  return false;
4365}
4366
4367/// getObjCEncodingTypeSize returns size of type for objective-c encoding
4368/// purpose.
4369CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
4370  if (!type->isIncompleteArrayType() && type->isIncompleteType())
4371    return CharUnits::Zero();
4372
4373  CharUnits sz = getTypeSizeInChars(type);
4374
4375  // Make all integer and enum types at least as large as an int
4376  if (sz.isPositive() && type->isIntegralOrEnumerationType())
4377    sz = std::max(sz, getTypeSizeInChars(IntTy));
4378  // Treat arrays as pointers, since that's how they're passed in.
4379  else if (type->isArrayType())
4380    sz = getTypeSizeInChars(VoidPtrTy);
4381  return sz;
4382}
4383
4384static inline
4385std::string charUnitsToString(const CharUnits &CU) {
4386  return llvm::itostr(CU.getQuantity());
4387}
4388
4389/// getObjCEncodingForBlock - Return the encoded type for this block
4390/// declaration.
4391std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
4392  std::string S;
4393
4394  const BlockDecl *Decl = Expr->getBlockDecl();
4395  QualType BlockTy =
4396      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
4397  // Encode result type.
4398  getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(), S);
4399  // Compute size of all parameters.
4400  // Start with computing size of a pointer in number of bytes.
4401  // FIXME: There might(should) be a better way of doing this computation!
4402  SourceLocation Loc;
4403  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4404  CharUnits ParmOffset = PtrSize;
4405  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
4406       E = Decl->param_end(); PI != E; ++PI) {
4407    QualType PType = (*PI)->getType();
4408    CharUnits sz = getObjCEncodingTypeSize(PType);
4409    if (sz.isZero())
4410      continue;
4411    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
4412    ParmOffset += sz;
4413  }
4414  // Size of the argument frame
4415  S += charUnitsToString(ParmOffset);
4416  // Block pointer and offset.
4417  S += "@?0";
4418
4419  // Argument types.
4420  ParmOffset = PtrSize;
4421  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
4422       Decl->param_end(); PI != E; ++PI) {
4423    ParmVarDecl *PVDecl = *PI;
4424    QualType PType = PVDecl->getOriginalType();
4425    if (const ArrayType *AT =
4426          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4427      // Use array's original type only if it has known number of
4428      // elements.
4429      if (!isa<ConstantArrayType>(AT))
4430        PType = PVDecl->getType();
4431    } else if (PType->isFunctionType())
4432      PType = PVDecl->getType();
4433    getObjCEncodingForType(PType, S);
4434    S += charUnitsToString(ParmOffset);
4435    ParmOffset += getObjCEncodingTypeSize(PType);
4436  }
4437
4438  return S;
4439}
4440
4441bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
4442                                                std::string& S) {
4443  // Encode result type.
4444  getObjCEncodingForType(Decl->getResultType(), S);
4445  CharUnits ParmOffset;
4446  // Compute size of all parameters.
4447  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4448       E = Decl->param_end(); PI != E; ++PI) {
4449    QualType PType = (*PI)->getType();
4450    CharUnits sz = getObjCEncodingTypeSize(PType);
4451    if (sz.isZero())
4452      continue;
4453
4454    assert (sz.isPositive() &&
4455        "getObjCEncodingForFunctionDecl - Incomplete param type");
4456    ParmOffset += sz;
4457  }
4458  S += charUnitsToString(ParmOffset);
4459  ParmOffset = CharUnits::Zero();
4460
4461  // Argument types.
4462  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4463       E = Decl->param_end(); PI != E; ++PI) {
4464    ParmVarDecl *PVDecl = *PI;
4465    QualType PType = PVDecl->getOriginalType();
4466    if (const ArrayType *AT =
4467          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4468      // Use array's original type only if it has known number of
4469      // elements.
4470      if (!isa<ConstantArrayType>(AT))
4471        PType = PVDecl->getType();
4472    } else if (PType->isFunctionType())
4473      PType = PVDecl->getType();
4474    getObjCEncodingForType(PType, S);
4475    S += charUnitsToString(ParmOffset);
4476    ParmOffset += getObjCEncodingTypeSize(PType);
4477  }
4478
4479  return false;
4480}
4481
4482/// getObjCEncodingForMethodParameter - Return the encoded type for a single
4483/// method parameter or return type. If Extended, include class names and
4484/// block object types.
4485void ASTContext::getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
4486                                                   QualType T, std::string& S,
4487                                                   bool Extended) const {
4488  // Encode type qualifer, 'in', 'inout', etc. for the parameter.
4489  getObjCEncodingForTypeQualifier(QT, S);
4490  // Encode parameter type.
4491  getObjCEncodingForTypeImpl(T, S, true, true, 0,
4492                             true     /*OutermostType*/,
4493                             false    /*EncodingProperty*/,
4494                             false    /*StructField*/,
4495                             Extended /*EncodeBlockParameters*/,
4496                             Extended /*EncodeClassNames*/);
4497}
4498
4499/// getObjCEncodingForMethodDecl - Return the encoded type for this method
4500/// declaration.
4501bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
4502                                              std::string& S,
4503                                              bool Extended) const {
4504  // FIXME: This is not very efficient.
4505  // Encode return type.
4506  getObjCEncodingForMethodParameter(Decl->getObjCDeclQualifier(),
4507                                    Decl->getResultType(), S, Extended);
4508  // Compute size of all parameters.
4509  // Start with computing size of a pointer in number of bytes.
4510  // FIXME: There might(should) be a better way of doing this computation!
4511  SourceLocation Loc;
4512  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4513  // The first two arguments (self and _cmd) are pointers; account for
4514  // their size.
4515  CharUnits ParmOffset = 2 * PtrSize;
4516  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4517       E = Decl->sel_param_end(); PI != E; ++PI) {
4518    QualType PType = (*PI)->getType();
4519    CharUnits sz = getObjCEncodingTypeSize(PType);
4520    if (sz.isZero())
4521      continue;
4522
4523    assert (sz.isPositive() &&
4524        "getObjCEncodingForMethodDecl - Incomplete param type");
4525    ParmOffset += sz;
4526  }
4527  S += charUnitsToString(ParmOffset);
4528  S += "@0:";
4529  S += charUnitsToString(PtrSize);
4530
4531  // Argument types.
4532  ParmOffset = 2 * PtrSize;
4533  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4534       E = Decl->sel_param_end(); PI != E; ++PI) {
4535    const ParmVarDecl *PVDecl = *PI;
4536    QualType PType = PVDecl->getOriginalType();
4537    if (const ArrayType *AT =
4538          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4539      // Use array's original type only if it has known number of
4540      // elements.
4541      if (!isa<ConstantArrayType>(AT))
4542        PType = PVDecl->getType();
4543    } else if (PType->isFunctionType())
4544      PType = PVDecl->getType();
4545    getObjCEncodingForMethodParameter(PVDecl->getObjCDeclQualifier(),
4546                                      PType, S, Extended);
4547    S += charUnitsToString(ParmOffset);
4548    ParmOffset += getObjCEncodingTypeSize(PType);
4549  }
4550
4551  return false;
4552}
4553
4554/// getObjCEncodingForPropertyDecl - Return the encoded type for this
4555/// property declaration. If non-NULL, Container must be either an
4556/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
4557/// NULL when getting encodings for protocol properties.
4558/// Property attributes are stored as a comma-delimited C string. The simple
4559/// attributes readonly and bycopy are encoded as single characters. The
4560/// parametrized attributes, getter=name, setter=name, and ivar=name, are
4561/// encoded as single characters, followed by an identifier. Property types
4562/// are also encoded as a parametrized attribute. The characters used to encode
4563/// these attributes are defined by the following enumeration:
4564/// @code
4565/// enum PropertyAttributes {
4566/// kPropertyReadOnly = 'R',   // property is read-only.
4567/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
4568/// kPropertyByref = '&',  // property is a reference to the value last assigned
4569/// kPropertyDynamic = 'D',    // property is dynamic
4570/// kPropertyGetter = 'G',     // followed by getter selector name
4571/// kPropertySetter = 'S',     // followed by setter selector name
4572/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
4573/// kPropertyType = 'T'              // followed by old-style type encoding.
4574/// kPropertyWeak = 'W'              // 'weak' property
4575/// kPropertyStrong = 'P'            // property GC'able
4576/// kPropertyNonAtomic = 'N'         // property non-atomic
4577/// };
4578/// @endcode
4579void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
4580                                                const Decl *Container,
4581                                                std::string& S) const {
4582  // Collect information from the property implementation decl(s).
4583  bool Dynamic = false;
4584  ObjCPropertyImplDecl *SynthesizePID = 0;
4585
4586  // FIXME: Duplicated code due to poor abstraction.
4587  if (Container) {
4588    if (const ObjCCategoryImplDecl *CID =
4589        dyn_cast<ObjCCategoryImplDecl>(Container)) {
4590      for (ObjCCategoryImplDecl::propimpl_iterator
4591             i = CID->propimpl_begin(), e = CID->propimpl_end();
4592           i != e; ++i) {
4593        ObjCPropertyImplDecl *PID = *i;
4594        if (PID->getPropertyDecl() == PD) {
4595          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4596            Dynamic = true;
4597          } else {
4598            SynthesizePID = PID;
4599          }
4600        }
4601      }
4602    } else {
4603      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
4604      for (ObjCCategoryImplDecl::propimpl_iterator
4605             i = OID->propimpl_begin(), e = OID->propimpl_end();
4606           i != e; ++i) {
4607        ObjCPropertyImplDecl *PID = *i;
4608        if (PID->getPropertyDecl() == PD) {
4609          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4610            Dynamic = true;
4611          } else {
4612            SynthesizePID = PID;
4613          }
4614        }
4615      }
4616    }
4617  }
4618
4619  // FIXME: This is not very efficient.
4620  S = "T";
4621
4622  // Encode result type.
4623  // GCC has some special rules regarding encoding of properties which
4624  // closely resembles encoding of ivars.
4625  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
4626                             true /* outermost type */,
4627                             true /* encoding for property */);
4628
4629  if (PD->isReadOnly()) {
4630    S += ",R";
4631  } else {
4632    switch (PD->getSetterKind()) {
4633    case ObjCPropertyDecl::Assign: break;
4634    case ObjCPropertyDecl::Copy:   S += ",C"; break;
4635    case ObjCPropertyDecl::Retain: S += ",&"; break;
4636    case ObjCPropertyDecl::Weak:   S += ",W"; break;
4637    }
4638  }
4639
4640  // It really isn't clear at all what this means, since properties
4641  // are "dynamic by default".
4642  if (Dynamic)
4643    S += ",D";
4644
4645  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
4646    S += ",N";
4647
4648  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
4649    S += ",G";
4650    S += PD->getGetterName().getAsString();
4651  }
4652
4653  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
4654    S += ",S";
4655    S += PD->getSetterName().getAsString();
4656  }
4657
4658  if (SynthesizePID) {
4659    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
4660    S += ",V";
4661    S += OID->getNameAsString();
4662  }
4663
4664  // FIXME: OBJCGC: weak & strong
4665}
4666
4667/// getLegacyIntegralTypeEncoding -
4668/// Another legacy compatibility encoding: 32-bit longs are encoded as
4669/// 'l' or 'L' , but not always.  For typedefs, we need to use
4670/// 'i' or 'I' instead if encoding a struct field, or a pointer!
4671///
4672void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
4673  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
4674    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
4675      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
4676        PointeeTy = UnsignedIntTy;
4677      else
4678        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
4679          PointeeTy = IntTy;
4680    }
4681  }
4682}
4683
4684void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
4685                                        const FieldDecl *Field) const {
4686  // We follow the behavior of gcc, expanding structures which are
4687  // directly pointed to, and expanding embedded structures. Note that
4688  // these rules are sufficient to prevent recursive encoding of the
4689  // same type.
4690  getObjCEncodingForTypeImpl(T, S, true, true, Field,
4691                             true /* outermost type */);
4692}
4693
4694static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
4695    switch (T->getAs<BuiltinType>()->getKind()) {
4696    default: llvm_unreachable("Unhandled builtin type kind");
4697    case BuiltinType::Void:       return 'v';
4698    case BuiltinType::Bool:       return 'B';
4699    case BuiltinType::Char_U:
4700    case BuiltinType::UChar:      return 'C';
4701    case BuiltinType::UShort:     return 'S';
4702    case BuiltinType::UInt:       return 'I';
4703    case BuiltinType::ULong:
4704        return C->getIntWidth(T) == 32 ? 'L' : 'Q';
4705    case BuiltinType::UInt128:    return 'T';
4706    case BuiltinType::ULongLong:  return 'Q';
4707    case BuiltinType::Char_S:
4708    case BuiltinType::SChar:      return 'c';
4709    case BuiltinType::Short:      return 's';
4710    case BuiltinType::WChar_S:
4711    case BuiltinType::WChar_U:
4712    case BuiltinType::Int:        return 'i';
4713    case BuiltinType::Long:
4714      return C->getIntWidth(T) == 32 ? 'l' : 'q';
4715    case BuiltinType::LongLong:   return 'q';
4716    case BuiltinType::Int128:     return 't';
4717    case BuiltinType::Float:      return 'f';
4718    case BuiltinType::Double:     return 'd';
4719    case BuiltinType::LongDouble: return 'D';
4720    }
4721}
4722
4723static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
4724  EnumDecl *Enum = ET->getDecl();
4725
4726  // The encoding of an non-fixed enum type is always 'i', regardless of size.
4727  if (!Enum->isFixed())
4728    return 'i';
4729
4730  // The encoding of a fixed enum type matches its fixed underlying type.
4731  return ObjCEncodingForPrimitiveKind(C, Enum->getIntegerType());
4732}
4733
4734static void EncodeBitField(const ASTContext *Ctx, std::string& S,
4735                           QualType T, const FieldDecl *FD) {
4736  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
4737  S += 'b';
4738  // The NeXT runtime encodes bit fields as b followed by the number of bits.
4739  // The GNU runtime requires more information; bitfields are encoded as b,
4740  // then the offset (in bits) of the first element, then the type of the
4741  // bitfield, then the size in bits.  For example, in this structure:
4742  //
4743  // struct
4744  // {
4745  //    int integer;
4746  //    int flags:2;
4747  // };
4748  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
4749  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
4750  // information is not especially sensible, but we're stuck with it for
4751  // compatibility with GCC, although providing it breaks anything that
4752  // actually uses runtime introspection and wants to work on both runtimes...
4753  if (Ctx->getLangOpts().ObjCRuntime.isGNUFamily()) {
4754    const RecordDecl *RD = FD->getParent();
4755    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
4756    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
4757    if (const EnumType *ET = T->getAs<EnumType>())
4758      S += ObjCEncodingForEnumType(Ctx, ET);
4759    else
4760      S += ObjCEncodingForPrimitiveKind(Ctx, T);
4761  }
4762  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
4763}
4764
4765// FIXME: Use SmallString for accumulating string.
4766void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
4767                                            bool ExpandPointedToStructures,
4768                                            bool ExpandStructures,
4769                                            const FieldDecl *FD,
4770                                            bool OutermostType,
4771                                            bool EncodingProperty,
4772                                            bool StructField,
4773                                            bool EncodeBlockParameters,
4774                                            bool EncodeClassNames) const {
4775  if (T->getAs<BuiltinType>()) {
4776    if (FD && FD->isBitField())
4777      return EncodeBitField(this, S, T, FD);
4778    S += ObjCEncodingForPrimitiveKind(this, T);
4779    return;
4780  }
4781
4782  if (const ComplexType *CT = T->getAs<ComplexType>()) {
4783    S += 'j';
4784    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
4785                               false);
4786    return;
4787  }
4788
4789  // encoding for pointer or r3eference types.
4790  QualType PointeeTy;
4791  if (const PointerType *PT = T->getAs<PointerType>()) {
4792    if (PT->isObjCSelType()) {
4793      S += ':';
4794      return;
4795    }
4796    PointeeTy = PT->getPointeeType();
4797  }
4798  else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4799    PointeeTy = RT->getPointeeType();
4800  if (!PointeeTy.isNull()) {
4801    bool isReadOnly = false;
4802    // For historical/compatibility reasons, the read-only qualifier of the
4803    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
4804    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
4805    // Also, do not emit the 'r' for anything but the outermost type!
4806    if (isa<TypedefType>(T.getTypePtr())) {
4807      if (OutermostType && T.isConstQualified()) {
4808        isReadOnly = true;
4809        S += 'r';
4810      }
4811    } else if (OutermostType) {
4812      QualType P = PointeeTy;
4813      while (P->getAs<PointerType>())
4814        P = P->getAs<PointerType>()->getPointeeType();
4815      if (P.isConstQualified()) {
4816        isReadOnly = true;
4817        S += 'r';
4818      }
4819    }
4820    if (isReadOnly) {
4821      // Another legacy compatibility encoding. Some ObjC qualifier and type
4822      // combinations need to be rearranged.
4823      // Rewrite "in const" from "nr" to "rn"
4824      if (StringRef(S).endswith("nr"))
4825        S.replace(S.end()-2, S.end(), "rn");
4826    }
4827
4828    if (PointeeTy->isCharType()) {
4829      // char pointer types should be encoded as '*' unless it is a
4830      // type that has been typedef'd to 'BOOL'.
4831      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
4832        S += '*';
4833        return;
4834      }
4835    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
4836      // GCC binary compat: Need to convert "struct objc_class *" to "#".
4837      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
4838        S += '#';
4839        return;
4840      }
4841      // GCC binary compat: Need to convert "struct objc_object *" to "@".
4842      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
4843        S += '@';
4844        return;
4845      }
4846      // fall through...
4847    }
4848    S += '^';
4849    getLegacyIntegralTypeEncoding(PointeeTy);
4850
4851    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
4852                               NULL);
4853    return;
4854  }
4855
4856  if (const ArrayType *AT =
4857      // Ignore type qualifiers etc.
4858        dyn_cast<ArrayType>(T->getCanonicalTypeInternal())) {
4859    if (isa<IncompleteArrayType>(AT) && !StructField) {
4860      // Incomplete arrays are encoded as a pointer to the array element.
4861      S += '^';
4862
4863      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4864                                 false, ExpandStructures, FD);
4865    } else {
4866      S += '[';
4867
4868      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
4869        if (getTypeSize(CAT->getElementType()) == 0)
4870          S += '0';
4871        else
4872          S += llvm::utostr(CAT->getSize().getZExtValue());
4873      } else {
4874        //Variable length arrays are encoded as a regular array with 0 elements.
4875        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
4876               "Unknown array type!");
4877        S += '0';
4878      }
4879
4880      getObjCEncodingForTypeImpl(AT->getElementType(), S,
4881                                 false, ExpandStructures, FD);
4882      S += ']';
4883    }
4884    return;
4885  }
4886
4887  if (T->getAs<FunctionType>()) {
4888    S += '?';
4889    return;
4890  }
4891
4892  if (const RecordType *RTy = T->getAs<RecordType>()) {
4893    RecordDecl *RDecl = RTy->getDecl();
4894    S += RDecl->isUnion() ? '(' : '{';
4895    // Anonymous structures print as '?'
4896    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
4897      S += II->getName();
4898      if (ClassTemplateSpecializationDecl *Spec
4899          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
4900        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
4901        std::string TemplateArgsStr
4902          = TemplateSpecializationType::PrintTemplateArgumentList(
4903                                            TemplateArgs.data(),
4904                                            TemplateArgs.size(),
4905                                            (*this).getPrintingPolicy());
4906
4907        S += TemplateArgsStr;
4908      }
4909    } else {
4910      S += '?';
4911    }
4912    if (ExpandStructures) {
4913      S += '=';
4914      if (!RDecl->isUnion()) {
4915        getObjCEncodingForStructureImpl(RDecl, S, FD);
4916      } else {
4917        for (RecordDecl::field_iterator Field = RDecl->field_begin(),
4918                                     FieldEnd = RDecl->field_end();
4919             Field != FieldEnd; ++Field) {
4920          if (FD) {
4921            S += '"';
4922            S += Field->getNameAsString();
4923            S += '"';
4924          }
4925
4926          // Special case bit-fields.
4927          if (Field->isBitField()) {
4928            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
4929                                       *Field);
4930          } else {
4931            QualType qt = Field->getType();
4932            getLegacyIntegralTypeEncoding(qt);
4933            getObjCEncodingForTypeImpl(qt, S, false, true,
4934                                       FD, /*OutermostType*/false,
4935                                       /*EncodingProperty*/false,
4936                                       /*StructField*/true);
4937          }
4938        }
4939      }
4940    }
4941    S += RDecl->isUnion() ? ')' : '}';
4942    return;
4943  }
4944
4945  if (const EnumType *ET = T->getAs<EnumType>()) {
4946    if (FD && FD->isBitField())
4947      EncodeBitField(this, S, T, FD);
4948    else
4949      S += ObjCEncodingForEnumType(this, ET);
4950    return;
4951  }
4952
4953  if (const BlockPointerType *BT = T->getAs<BlockPointerType>()) {
4954    S += "@?"; // Unlike a pointer-to-function, which is "^?".
4955    if (EncodeBlockParameters) {
4956      const FunctionType *FT = BT->getPointeeType()->getAs<FunctionType>();
4957
4958      S += '<';
4959      // Block return type
4960      getObjCEncodingForTypeImpl(FT->getResultType(), S,
4961                                 ExpandPointedToStructures, ExpandStructures,
4962                                 FD,
4963                                 false /* OutermostType */,
4964                                 EncodingProperty,
4965                                 false /* StructField */,
4966                                 EncodeBlockParameters,
4967                                 EncodeClassNames);
4968      // Block self
4969      S += "@?";
4970      // Block parameters
4971      if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT)) {
4972        for (FunctionProtoType::arg_type_iterator I = FPT->arg_type_begin(),
4973               E = FPT->arg_type_end(); I && (I != E); ++I) {
4974          getObjCEncodingForTypeImpl(*I, S,
4975                                     ExpandPointedToStructures,
4976                                     ExpandStructures,
4977                                     FD,
4978                                     false /* OutermostType */,
4979                                     EncodingProperty,
4980                                     false /* StructField */,
4981                                     EncodeBlockParameters,
4982                                     EncodeClassNames);
4983        }
4984      }
4985      S += '>';
4986    }
4987    return;
4988  }
4989
4990  // Ignore protocol qualifiers when mangling at this level.
4991  if (const ObjCObjectType *OT = T->getAs<ObjCObjectType>())
4992    T = OT->getBaseType();
4993
4994  if (const ObjCInterfaceType *OIT = T->getAs<ObjCInterfaceType>()) {
4995    // @encode(class_name)
4996    ObjCInterfaceDecl *OI = OIT->getDecl();
4997    S += '{';
4998    const IdentifierInfo *II = OI->getIdentifier();
4999    S += II->getName();
5000    S += '=';
5001    SmallVector<const ObjCIvarDecl*, 32> Ivars;
5002    DeepCollectObjCIvars(OI, true, Ivars);
5003    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
5004      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
5005      if (Field->isBitField())
5006        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
5007      else
5008        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
5009    }
5010    S += '}';
5011    return;
5012  }
5013
5014  if (const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>()) {
5015    if (OPT->isObjCIdType()) {
5016      S += '@';
5017      return;
5018    }
5019
5020    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
5021      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
5022      // Since this is a binary compatibility issue, need to consult with runtime
5023      // folks. Fortunately, this is a *very* obsure construct.
5024      S += '#';
5025      return;
5026    }
5027
5028    if (OPT->isObjCQualifiedIdType()) {
5029      getObjCEncodingForTypeImpl(getObjCIdType(), S,
5030                                 ExpandPointedToStructures,
5031                                 ExpandStructures, FD);
5032      if (FD || EncodingProperty || EncodeClassNames) {
5033        // Note that we do extended encoding of protocol qualifer list
5034        // Only when doing ivar or property encoding.
5035        S += '"';
5036        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
5037             E = OPT->qual_end(); I != E; ++I) {
5038          S += '<';
5039          S += (*I)->getNameAsString();
5040          S += '>';
5041        }
5042        S += '"';
5043      }
5044      return;
5045    }
5046
5047    QualType PointeeTy = OPT->getPointeeType();
5048    if (!EncodingProperty &&
5049        isa<TypedefType>(PointeeTy.getTypePtr())) {
5050      // Another historical/compatibility reason.
5051      // We encode the underlying type which comes out as
5052      // {...};
5053      S += '^';
5054      getObjCEncodingForTypeImpl(PointeeTy, S,
5055                                 false, ExpandPointedToStructures,
5056                                 NULL);
5057      return;
5058    }
5059
5060    S += '@';
5061    if (OPT->getInterfaceDecl() &&
5062        (FD || EncodingProperty || EncodeClassNames)) {
5063      S += '"';
5064      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
5065      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
5066           E = OPT->qual_end(); I != E; ++I) {
5067        S += '<';
5068        S += (*I)->getNameAsString();
5069        S += '>';
5070      }
5071      S += '"';
5072    }
5073    return;
5074  }
5075
5076  // gcc just blithely ignores member pointers.
5077  // TODO: maybe there should be a mangling for these
5078  if (T->getAs<MemberPointerType>())
5079    return;
5080
5081  if (T->isVectorType()) {
5082    // This matches gcc's encoding, even though technically it is
5083    // insufficient.
5084    // FIXME. We should do a better job than gcc.
5085    return;
5086  }
5087
5088  llvm_unreachable("@encode for type not implemented!");
5089}
5090
5091void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
5092                                                 std::string &S,
5093                                                 const FieldDecl *FD,
5094                                                 bool includeVBases) const {
5095  assert(RDecl && "Expected non-null RecordDecl");
5096  assert(!RDecl->isUnion() && "Should not be called for unions");
5097  if (!RDecl->getDefinition())
5098    return;
5099
5100  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
5101  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
5102  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
5103
5104  if (CXXRec) {
5105    for (CXXRecordDecl::base_class_iterator
5106           BI = CXXRec->bases_begin(),
5107           BE = CXXRec->bases_end(); BI != BE; ++BI) {
5108      if (!BI->isVirtual()) {
5109        CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
5110        if (base->isEmpty())
5111          continue;
5112        uint64_t offs = toBits(layout.getBaseClassOffset(base));
5113        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5114                                  std::make_pair(offs, base));
5115      }
5116    }
5117  }
5118
5119  unsigned i = 0;
5120  for (RecordDecl::field_iterator Field = RDecl->field_begin(),
5121                               FieldEnd = RDecl->field_end();
5122       Field != FieldEnd; ++Field, ++i) {
5123    uint64_t offs = layout.getFieldOffset(i);
5124    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5125                              std::make_pair(offs, *Field));
5126  }
5127
5128  if (CXXRec && includeVBases) {
5129    for (CXXRecordDecl::base_class_iterator
5130           BI = CXXRec->vbases_begin(),
5131           BE = CXXRec->vbases_end(); BI != BE; ++BI) {
5132      CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
5133      if (base->isEmpty())
5134        continue;
5135      uint64_t offs = toBits(layout.getVBaseClassOffset(base));
5136      if (FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
5137        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
5138                                  std::make_pair(offs, base));
5139    }
5140  }
5141
5142  CharUnits size;
5143  if (CXXRec) {
5144    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
5145  } else {
5146    size = layout.getSize();
5147  }
5148
5149  uint64_t CurOffs = 0;
5150  std::multimap<uint64_t, NamedDecl *>::iterator
5151    CurLayObj = FieldOrBaseOffsets.begin();
5152
5153  if (CXXRec && CXXRec->isDynamicClass() &&
5154      (CurLayObj == FieldOrBaseOffsets.end() || CurLayObj->first != 0)) {
5155    if (FD) {
5156      S += "\"_vptr$";
5157      std::string recname = CXXRec->getNameAsString();
5158      if (recname.empty()) recname = "?";
5159      S += recname;
5160      S += '"';
5161    }
5162    S += "^^?";
5163    CurOffs += getTypeSize(VoidPtrTy);
5164  }
5165
5166  if (!RDecl->hasFlexibleArrayMember()) {
5167    // Mark the end of the structure.
5168    uint64_t offs = toBits(size);
5169    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5170                              std::make_pair(offs, (NamedDecl*)0));
5171  }
5172
5173  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
5174    assert(CurOffs <= CurLayObj->first);
5175
5176    if (CurOffs < CurLayObj->first) {
5177      uint64_t padding = CurLayObj->first - CurOffs;
5178      // FIXME: There doesn't seem to be a way to indicate in the encoding that
5179      // packing/alignment of members is different that normal, in which case
5180      // the encoding will be out-of-sync with the real layout.
5181      // If the runtime switches to just consider the size of types without
5182      // taking into account alignment, we could make padding explicit in the
5183      // encoding (e.g. using arrays of chars). The encoding strings would be
5184      // longer then though.
5185      CurOffs += padding;
5186    }
5187
5188    NamedDecl *dcl = CurLayObj->second;
5189    if (dcl == 0)
5190      break; // reached end of structure.
5191
5192    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
5193      // We expand the bases without their virtual bases since those are going
5194      // in the initial structure. Note that this differs from gcc which
5195      // expands virtual bases each time one is encountered in the hierarchy,
5196      // making the encoding type bigger than it really is.
5197      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false);
5198      assert(!base->isEmpty());
5199      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
5200    } else {
5201      FieldDecl *field = cast<FieldDecl>(dcl);
5202      if (FD) {
5203        S += '"';
5204        S += field->getNameAsString();
5205        S += '"';
5206      }
5207
5208      if (field->isBitField()) {
5209        EncodeBitField(this, S, field->getType(), field);
5210        CurOffs += field->getBitWidthValue(*this);
5211      } else {
5212        QualType qt = field->getType();
5213        getLegacyIntegralTypeEncoding(qt);
5214        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
5215                                   /*OutermostType*/false,
5216                                   /*EncodingProperty*/false,
5217                                   /*StructField*/true);
5218        CurOffs += getTypeSize(field->getType());
5219      }
5220    }
5221  }
5222}
5223
5224void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
5225                                                 std::string& S) const {
5226  if (QT & Decl::OBJC_TQ_In)
5227    S += 'n';
5228  if (QT & Decl::OBJC_TQ_Inout)
5229    S += 'N';
5230  if (QT & Decl::OBJC_TQ_Out)
5231    S += 'o';
5232  if (QT & Decl::OBJC_TQ_Bycopy)
5233    S += 'O';
5234  if (QT & Decl::OBJC_TQ_Byref)
5235    S += 'R';
5236  if (QT & Decl::OBJC_TQ_Oneway)
5237    S += 'V';
5238}
5239
5240TypedefDecl *ASTContext::getObjCIdDecl() const {
5241  if (!ObjCIdDecl) {
5242    QualType T = getObjCObjectType(ObjCBuiltinIdTy, 0, 0);
5243    T = getObjCObjectPointerType(T);
5244    TypeSourceInfo *IdInfo = getTrivialTypeSourceInfo(T);
5245    ObjCIdDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
5246                                     getTranslationUnitDecl(),
5247                                     SourceLocation(), SourceLocation(),
5248                                     &Idents.get("id"), IdInfo);
5249  }
5250
5251  return ObjCIdDecl;
5252}
5253
5254TypedefDecl *ASTContext::getObjCSelDecl() const {
5255  if (!ObjCSelDecl) {
5256    QualType SelT = getPointerType(ObjCBuiltinSelTy);
5257    TypeSourceInfo *SelInfo = getTrivialTypeSourceInfo(SelT);
5258    ObjCSelDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
5259                                      getTranslationUnitDecl(),
5260                                      SourceLocation(), SourceLocation(),
5261                                      &Idents.get("SEL"), SelInfo);
5262  }
5263  return ObjCSelDecl;
5264}
5265
5266TypedefDecl *ASTContext::getObjCClassDecl() const {
5267  if (!ObjCClassDecl) {
5268    QualType T = getObjCObjectType(ObjCBuiltinClassTy, 0, 0);
5269    T = getObjCObjectPointerType(T);
5270    TypeSourceInfo *ClassInfo = getTrivialTypeSourceInfo(T);
5271    ObjCClassDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
5272                                        getTranslationUnitDecl(),
5273                                        SourceLocation(), SourceLocation(),
5274                                        &Idents.get("Class"), ClassInfo);
5275  }
5276
5277  return ObjCClassDecl;
5278}
5279
5280ObjCInterfaceDecl *ASTContext::getObjCProtocolDecl() const {
5281  if (!ObjCProtocolClassDecl) {
5282    ObjCProtocolClassDecl
5283      = ObjCInterfaceDecl::Create(*this, getTranslationUnitDecl(),
5284                                  SourceLocation(),
5285                                  &Idents.get("Protocol"),
5286                                  /*PrevDecl=*/0,
5287                                  SourceLocation(), true);
5288  }
5289
5290  return ObjCProtocolClassDecl;
5291}
5292
5293//===----------------------------------------------------------------------===//
5294// __builtin_va_list Construction Functions
5295//===----------------------------------------------------------------------===//
5296
5297static TypedefDecl *CreateCharPtrBuiltinVaListDecl(const ASTContext *Context) {
5298  // typedef char* __builtin_va_list;
5299  QualType CharPtrType = Context->getPointerType(Context->CharTy);
5300  TypeSourceInfo *TInfo
5301    = Context->getTrivialTypeSourceInfo(CharPtrType);
5302
5303  TypedefDecl *VaListTypeDecl
5304    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5305                          Context->getTranslationUnitDecl(),
5306                          SourceLocation(), SourceLocation(),
5307                          &Context->Idents.get("__builtin_va_list"),
5308                          TInfo);
5309  return VaListTypeDecl;
5310}
5311
5312static TypedefDecl *CreateVoidPtrBuiltinVaListDecl(const ASTContext *Context) {
5313  // typedef void* __builtin_va_list;
5314  QualType VoidPtrType = Context->getPointerType(Context->VoidTy);
5315  TypeSourceInfo *TInfo
5316    = Context->getTrivialTypeSourceInfo(VoidPtrType);
5317
5318  TypedefDecl *VaListTypeDecl
5319    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5320                          Context->getTranslationUnitDecl(),
5321                          SourceLocation(), SourceLocation(),
5322                          &Context->Idents.get("__builtin_va_list"),
5323                          TInfo);
5324  return VaListTypeDecl;
5325}
5326
5327static TypedefDecl *CreatePowerABIBuiltinVaListDecl(const ASTContext *Context) {
5328  // typedef struct __va_list_tag {
5329  RecordDecl *VaListTagDecl;
5330
5331  VaListTagDecl = CreateRecordDecl(*Context, TTK_Struct,
5332                                   Context->getTranslationUnitDecl(),
5333                                   &Context->Idents.get("__va_list_tag"));
5334  VaListTagDecl->startDefinition();
5335
5336  const size_t NumFields = 5;
5337  QualType FieldTypes[NumFields];
5338  const char *FieldNames[NumFields];
5339
5340  //   unsigned char gpr;
5341  FieldTypes[0] = Context->UnsignedCharTy;
5342  FieldNames[0] = "gpr";
5343
5344  //   unsigned char fpr;
5345  FieldTypes[1] = Context->UnsignedCharTy;
5346  FieldNames[1] = "fpr";
5347
5348  //   unsigned short reserved;
5349  FieldTypes[2] = Context->UnsignedShortTy;
5350  FieldNames[2] = "reserved";
5351
5352  //   void* overflow_arg_area;
5353  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
5354  FieldNames[3] = "overflow_arg_area";
5355
5356  //   void* reg_save_area;
5357  FieldTypes[4] = Context->getPointerType(Context->VoidTy);
5358  FieldNames[4] = "reg_save_area";
5359
5360  // Create fields
5361  for (unsigned i = 0; i < NumFields; ++i) {
5362    FieldDecl *Field = FieldDecl::Create(*Context, VaListTagDecl,
5363                                         SourceLocation(),
5364                                         SourceLocation(),
5365                                         &Context->Idents.get(FieldNames[i]),
5366                                         FieldTypes[i], /*TInfo=*/0,
5367                                         /*BitWidth=*/0,
5368                                         /*Mutable=*/false,
5369                                         ICIS_NoInit);
5370    Field->setAccess(AS_public);
5371    VaListTagDecl->addDecl(Field);
5372  }
5373  VaListTagDecl->completeDefinition();
5374  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
5375  Context->VaListTagTy = VaListTagType;
5376
5377  // } __va_list_tag;
5378  TypedefDecl *VaListTagTypedefDecl
5379    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5380                          Context->getTranslationUnitDecl(),
5381                          SourceLocation(), SourceLocation(),
5382                          &Context->Idents.get("__va_list_tag"),
5383                          Context->getTrivialTypeSourceInfo(VaListTagType));
5384  QualType VaListTagTypedefType =
5385    Context->getTypedefType(VaListTagTypedefDecl);
5386
5387  // typedef __va_list_tag __builtin_va_list[1];
5388  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
5389  QualType VaListTagArrayType
5390    = Context->getConstantArrayType(VaListTagTypedefType,
5391                                    Size, ArrayType::Normal, 0);
5392  TypeSourceInfo *TInfo
5393    = Context->getTrivialTypeSourceInfo(VaListTagArrayType);
5394  TypedefDecl *VaListTypedefDecl
5395    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5396                          Context->getTranslationUnitDecl(),
5397                          SourceLocation(), SourceLocation(),
5398                          &Context->Idents.get("__builtin_va_list"),
5399                          TInfo);
5400
5401  return VaListTypedefDecl;
5402}
5403
5404static TypedefDecl *
5405CreateX86_64ABIBuiltinVaListDecl(const ASTContext *Context) {
5406  // typedef struct __va_list_tag {
5407  RecordDecl *VaListTagDecl;
5408  VaListTagDecl = CreateRecordDecl(*Context, TTK_Struct,
5409                                   Context->getTranslationUnitDecl(),
5410                                   &Context->Idents.get("__va_list_tag"));
5411  VaListTagDecl->startDefinition();
5412
5413  const size_t NumFields = 4;
5414  QualType FieldTypes[NumFields];
5415  const char *FieldNames[NumFields];
5416
5417  //   unsigned gp_offset;
5418  FieldTypes[0] = Context->UnsignedIntTy;
5419  FieldNames[0] = "gp_offset";
5420
5421  //   unsigned fp_offset;
5422  FieldTypes[1] = Context->UnsignedIntTy;
5423  FieldNames[1] = "fp_offset";
5424
5425  //   void* overflow_arg_area;
5426  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
5427  FieldNames[2] = "overflow_arg_area";
5428
5429  //   void* reg_save_area;
5430  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
5431  FieldNames[3] = "reg_save_area";
5432
5433  // Create fields
5434  for (unsigned i = 0; i < NumFields; ++i) {
5435    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
5436                                         VaListTagDecl,
5437                                         SourceLocation(),
5438                                         SourceLocation(),
5439                                         &Context->Idents.get(FieldNames[i]),
5440                                         FieldTypes[i], /*TInfo=*/0,
5441                                         /*BitWidth=*/0,
5442                                         /*Mutable=*/false,
5443                                         ICIS_NoInit);
5444    Field->setAccess(AS_public);
5445    VaListTagDecl->addDecl(Field);
5446  }
5447  VaListTagDecl->completeDefinition();
5448  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
5449  Context->VaListTagTy = VaListTagType;
5450
5451  // } __va_list_tag;
5452  TypedefDecl *VaListTagTypedefDecl
5453    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5454                          Context->getTranslationUnitDecl(),
5455                          SourceLocation(), SourceLocation(),
5456                          &Context->Idents.get("__va_list_tag"),
5457                          Context->getTrivialTypeSourceInfo(VaListTagType));
5458  QualType VaListTagTypedefType =
5459    Context->getTypedefType(VaListTagTypedefDecl);
5460
5461  // typedef __va_list_tag __builtin_va_list[1];
5462  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
5463  QualType VaListTagArrayType
5464    = Context->getConstantArrayType(VaListTagTypedefType,
5465                                      Size, ArrayType::Normal,0);
5466  TypeSourceInfo *TInfo
5467    = Context->getTrivialTypeSourceInfo(VaListTagArrayType);
5468  TypedefDecl *VaListTypedefDecl
5469    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5470                          Context->getTranslationUnitDecl(),
5471                          SourceLocation(), SourceLocation(),
5472                          &Context->Idents.get("__builtin_va_list"),
5473                          TInfo);
5474
5475  return VaListTypedefDecl;
5476}
5477
5478static TypedefDecl *CreatePNaClABIBuiltinVaListDecl(const ASTContext *Context) {
5479  // typedef int __builtin_va_list[4];
5480  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 4);
5481  QualType IntArrayType
5482    = Context->getConstantArrayType(Context->IntTy,
5483				    Size, ArrayType::Normal, 0);
5484  TypedefDecl *VaListTypedefDecl
5485    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5486                          Context->getTranslationUnitDecl(),
5487                          SourceLocation(), SourceLocation(),
5488                          &Context->Idents.get("__builtin_va_list"),
5489                          Context->getTrivialTypeSourceInfo(IntArrayType));
5490
5491  return VaListTypedefDecl;
5492}
5493
5494static TypedefDecl *CreateVaListDecl(const ASTContext *Context,
5495                                     TargetInfo::BuiltinVaListKind Kind) {
5496  switch (Kind) {
5497  case TargetInfo::CharPtrBuiltinVaList:
5498    return CreateCharPtrBuiltinVaListDecl(Context);
5499  case TargetInfo::VoidPtrBuiltinVaList:
5500    return CreateVoidPtrBuiltinVaListDecl(Context);
5501  case TargetInfo::PowerABIBuiltinVaList:
5502    return CreatePowerABIBuiltinVaListDecl(Context);
5503  case TargetInfo::X86_64ABIBuiltinVaList:
5504    return CreateX86_64ABIBuiltinVaListDecl(Context);
5505  case TargetInfo::PNaClABIBuiltinVaList:
5506    return CreatePNaClABIBuiltinVaListDecl(Context);
5507  }
5508
5509  llvm_unreachable("Unhandled __builtin_va_list type kind");
5510}
5511
5512TypedefDecl *ASTContext::getBuiltinVaListDecl() const {
5513  if (!BuiltinVaListDecl)
5514    BuiltinVaListDecl = CreateVaListDecl(this, Target->getBuiltinVaListKind());
5515
5516  return BuiltinVaListDecl;
5517}
5518
5519QualType ASTContext::getVaListTagType() const {
5520  // Force the creation of VaListTagTy by building the __builtin_va_list
5521  // declaration.
5522  if (VaListTagTy.isNull())
5523    (void) getBuiltinVaListDecl();
5524
5525  return VaListTagTy;
5526}
5527
5528void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
5529  assert(ObjCConstantStringType.isNull() &&
5530         "'NSConstantString' type already set!");
5531
5532  ObjCConstantStringType = getObjCInterfaceType(Decl);
5533}
5534
5535/// \brief Retrieve the template name that corresponds to a non-empty
5536/// lookup.
5537TemplateName
5538ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
5539                                      UnresolvedSetIterator End) const {
5540  unsigned size = End - Begin;
5541  assert(size > 1 && "set is not overloaded!");
5542
5543  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
5544                          size * sizeof(FunctionTemplateDecl*));
5545  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
5546
5547  NamedDecl **Storage = OT->getStorage();
5548  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
5549    NamedDecl *D = *I;
5550    assert(isa<FunctionTemplateDecl>(D) ||
5551           (isa<UsingShadowDecl>(D) &&
5552            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
5553    *Storage++ = D;
5554  }
5555
5556  return TemplateName(OT);
5557}
5558
5559/// \brief Retrieve the template name that represents a qualified
5560/// template name such as \c std::vector.
5561TemplateName
5562ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
5563                                     bool TemplateKeyword,
5564                                     TemplateDecl *Template) const {
5565  assert(NNS && "Missing nested-name-specifier in qualified template name");
5566
5567  // FIXME: Canonicalization?
5568  llvm::FoldingSetNodeID ID;
5569  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
5570
5571  void *InsertPos = 0;
5572  QualifiedTemplateName *QTN =
5573    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5574  if (!QTN) {
5575    QTN = new (*this, llvm::alignOf<QualifiedTemplateName>())
5576        QualifiedTemplateName(NNS, TemplateKeyword, Template);
5577    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
5578  }
5579
5580  return TemplateName(QTN);
5581}
5582
5583/// \brief Retrieve the template name that represents a dependent
5584/// template name such as \c MetaFun::template apply.
5585TemplateName
5586ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
5587                                     const IdentifierInfo *Name) const {
5588  assert((!NNS || NNS->isDependent()) &&
5589         "Nested name specifier must be dependent");
5590
5591  llvm::FoldingSetNodeID ID;
5592  DependentTemplateName::Profile(ID, NNS, Name);
5593
5594  void *InsertPos = 0;
5595  DependentTemplateName *QTN =
5596    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5597
5598  if (QTN)
5599    return TemplateName(QTN);
5600
5601  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
5602  if (CanonNNS == NNS) {
5603    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
5604        DependentTemplateName(NNS, Name);
5605  } else {
5606    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
5607    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
5608        DependentTemplateName(NNS, Name, Canon);
5609    DependentTemplateName *CheckQTN =
5610      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5611    assert(!CheckQTN && "Dependent type name canonicalization broken");
5612    (void)CheckQTN;
5613  }
5614
5615  DependentTemplateNames.InsertNode(QTN, InsertPos);
5616  return TemplateName(QTN);
5617}
5618
5619/// \brief Retrieve the template name that represents a dependent
5620/// template name such as \c MetaFun::template operator+.
5621TemplateName
5622ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
5623                                     OverloadedOperatorKind Operator) const {
5624  assert((!NNS || NNS->isDependent()) &&
5625         "Nested name specifier must be dependent");
5626
5627  llvm::FoldingSetNodeID ID;
5628  DependentTemplateName::Profile(ID, NNS, Operator);
5629
5630  void *InsertPos = 0;
5631  DependentTemplateName *QTN
5632    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5633
5634  if (QTN)
5635    return TemplateName(QTN);
5636
5637  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
5638  if (CanonNNS == NNS) {
5639    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
5640        DependentTemplateName(NNS, Operator);
5641  } else {
5642    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
5643    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
5644        DependentTemplateName(NNS, Operator, Canon);
5645
5646    DependentTemplateName *CheckQTN
5647      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5648    assert(!CheckQTN && "Dependent template name canonicalization broken");
5649    (void)CheckQTN;
5650  }
5651
5652  DependentTemplateNames.InsertNode(QTN, InsertPos);
5653  return TemplateName(QTN);
5654}
5655
5656TemplateName
5657ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
5658                                         TemplateName replacement) const {
5659  llvm::FoldingSetNodeID ID;
5660  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
5661
5662  void *insertPos = 0;
5663  SubstTemplateTemplateParmStorage *subst
5664    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
5665
5666  if (!subst) {
5667    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
5668    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
5669  }
5670
5671  return TemplateName(subst);
5672}
5673
5674TemplateName
5675ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
5676                                       const TemplateArgument &ArgPack) const {
5677  ASTContext &Self = const_cast<ASTContext &>(*this);
5678  llvm::FoldingSetNodeID ID;
5679  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
5680
5681  void *InsertPos = 0;
5682  SubstTemplateTemplateParmPackStorage *Subst
5683    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
5684
5685  if (!Subst) {
5686    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
5687                                                           ArgPack.pack_size(),
5688                                                         ArgPack.pack_begin());
5689    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
5690  }
5691
5692  return TemplateName(Subst);
5693}
5694
5695/// getFromTargetType - Given one of the integer types provided by
5696/// TargetInfo, produce the corresponding type. The unsigned @p Type
5697/// is actually a value of type @c TargetInfo::IntType.
5698CanQualType ASTContext::getFromTargetType(unsigned Type) const {
5699  switch (Type) {
5700  case TargetInfo::NoInt: return CanQualType();
5701  case TargetInfo::SignedShort: return ShortTy;
5702  case TargetInfo::UnsignedShort: return UnsignedShortTy;
5703  case TargetInfo::SignedInt: return IntTy;
5704  case TargetInfo::UnsignedInt: return UnsignedIntTy;
5705  case TargetInfo::SignedLong: return LongTy;
5706  case TargetInfo::UnsignedLong: return UnsignedLongTy;
5707  case TargetInfo::SignedLongLong: return LongLongTy;
5708  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
5709  }
5710
5711  llvm_unreachable("Unhandled TargetInfo::IntType value");
5712}
5713
5714//===----------------------------------------------------------------------===//
5715//                        Type Predicates.
5716//===----------------------------------------------------------------------===//
5717
5718/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
5719/// garbage collection attribute.
5720///
5721Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
5722  if (getLangOpts().getGC() == LangOptions::NonGC)
5723    return Qualifiers::GCNone;
5724
5725  assert(getLangOpts().ObjC1);
5726  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
5727
5728  // Default behaviour under objective-C's gc is for ObjC pointers
5729  // (or pointers to them) be treated as though they were declared
5730  // as __strong.
5731  if (GCAttrs == Qualifiers::GCNone) {
5732    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
5733      return Qualifiers::Strong;
5734    else if (Ty->isPointerType())
5735      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
5736  } else {
5737    // It's not valid to set GC attributes on anything that isn't a
5738    // pointer.
5739#ifndef NDEBUG
5740    QualType CT = Ty->getCanonicalTypeInternal();
5741    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
5742      CT = AT->getElementType();
5743    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
5744#endif
5745  }
5746  return GCAttrs;
5747}
5748
5749//===----------------------------------------------------------------------===//
5750//                        Type Compatibility Testing
5751//===----------------------------------------------------------------------===//
5752
5753/// areCompatVectorTypes - Return true if the two specified vector types are
5754/// compatible.
5755static bool areCompatVectorTypes(const VectorType *LHS,
5756                                 const VectorType *RHS) {
5757  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
5758  return LHS->getElementType() == RHS->getElementType() &&
5759         LHS->getNumElements() == RHS->getNumElements();
5760}
5761
5762bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
5763                                          QualType SecondVec) {
5764  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
5765  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
5766
5767  if (hasSameUnqualifiedType(FirstVec, SecondVec))
5768    return true;
5769
5770  // Treat Neon vector types and most AltiVec vector types as if they are the
5771  // equivalent GCC vector types.
5772  const VectorType *First = FirstVec->getAs<VectorType>();
5773  const VectorType *Second = SecondVec->getAs<VectorType>();
5774  if (First->getNumElements() == Second->getNumElements() &&
5775      hasSameType(First->getElementType(), Second->getElementType()) &&
5776      First->getVectorKind() != VectorType::AltiVecPixel &&
5777      First->getVectorKind() != VectorType::AltiVecBool &&
5778      Second->getVectorKind() != VectorType::AltiVecPixel &&
5779      Second->getVectorKind() != VectorType::AltiVecBool)
5780    return true;
5781
5782  return false;
5783}
5784
5785//===----------------------------------------------------------------------===//
5786// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
5787//===----------------------------------------------------------------------===//
5788
5789/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
5790/// inheritance hierarchy of 'rProto'.
5791bool
5792ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
5793                                           ObjCProtocolDecl *rProto) const {
5794  if (declaresSameEntity(lProto, rProto))
5795    return true;
5796  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
5797       E = rProto->protocol_end(); PI != E; ++PI)
5798    if (ProtocolCompatibleWithProtocol(lProto, *PI))
5799      return true;
5800  return false;
5801}
5802
5803/// QualifiedIdConformsQualifiedId - compare id<pr,...> with id<pr1,...>
5804/// return true if lhs's protocols conform to rhs's protocol; false
5805/// otherwise.
5806bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
5807  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
5808    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
5809  return false;
5810}
5811
5812/// ObjCQualifiedClassTypesAreCompatible - compare  Class<pr,...> and
5813/// Class<pr1, ...>.
5814bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
5815                                                      QualType rhs) {
5816  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
5817  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5818  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
5819
5820  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5821       E = lhsQID->qual_end(); I != E; ++I) {
5822    bool match = false;
5823    ObjCProtocolDecl *lhsProto = *I;
5824    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5825         E = rhsOPT->qual_end(); J != E; ++J) {
5826      ObjCProtocolDecl *rhsProto = *J;
5827      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
5828        match = true;
5829        break;
5830      }
5831    }
5832    if (!match)
5833      return false;
5834  }
5835  return true;
5836}
5837
5838/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
5839/// ObjCQualifiedIDType.
5840bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
5841                                                   bool compare) {
5842  // Allow id<P..> and an 'id' or void* type in all cases.
5843  if (lhs->isVoidPointerType() ||
5844      lhs->isObjCIdType() || lhs->isObjCClassType())
5845    return true;
5846  else if (rhs->isVoidPointerType() ||
5847           rhs->isObjCIdType() || rhs->isObjCClassType())
5848    return true;
5849
5850  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
5851    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
5852
5853    if (!rhsOPT) return false;
5854
5855    if (rhsOPT->qual_empty()) {
5856      // If the RHS is a unqualified interface pointer "NSString*",
5857      // make sure we check the class hierarchy.
5858      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5859        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5860             E = lhsQID->qual_end(); I != E; ++I) {
5861          // when comparing an id<P> on lhs with a static type on rhs,
5862          // see if static class implements all of id's protocols, directly or
5863          // through its super class and categories.
5864          if (!rhsID->ClassImplementsProtocol(*I, true))
5865            return false;
5866        }
5867      }
5868      // If there are no qualifiers and no interface, we have an 'id'.
5869      return true;
5870    }
5871    // Both the right and left sides have qualifiers.
5872    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5873         E = lhsQID->qual_end(); I != E; ++I) {
5874      ObjCProtocolDecl *lhsProto = *I;
5875      bool match = false;
5876
5877      // when comparing an id<P> on lhs with a static type on rhs,
5878      // see if static class implements all of id's protocols, directly or
5879      // through its super class and categories.
5880      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
5881           E = rhsOPT->qual_end(); J != E; ++J) {
5882        ObjCProtocolDecl *rhsProto = *J;
5883        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5884            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5885          match = true;
5886          break;
5887        }
5888      }
5889      // If the RHS is a qualified interface pointer "NSString<P>*",
5890      // make sure we check the class hierarchy.
5891      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
5892        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
5893             E = lhsQID->qual_end(); I != E; ++I) {
5894          // when comparing an id<P> on lhs with a static type on rhs,
5895          // see if static class implements all of id's protocols, directly or
5896          // through its super class and categories.
5897          if (rhsID->ClassImplementsProtocol(*I, true)) {
5898            match = true;
5899            break;
5900          }
5901        }
5902      }
5903      if (!match)
5904        return false;
5905    }
5906
5907    return true;
5908  }
5909
5910  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
5911  assert(rhsQID && "One of the LHS/RHS should be id<x>");
5912
5913  if (const ObjCObjectPointerType *lhsOPT =
5914        lhs->getAsObjCInterfacePointerType()) {
5915    // If both the right and left sides have qualifiers.
5916    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
5917         E = lhsOPT->qual_end(); I != E; ++I) {
5918      ObjCProtocolDecl *lhsProto = *I;
5919      bool match = false;
5920
5921      // when comparing an id<P> on rhs with a static type on lhs,
5922      // see if static class implements all of id's protocols, directly or
5923      // through its super class and categories.
5924      // First, lhs protocols in the qualifier list must be found, direct
5925      // or indirect in rhs's qualifier list or it is a mismatch.
5926      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5927           E = rhsQID->qual_end(); J != E; ++J) {
5928        ObjCProtocolDecl *rhsProto = *J;
5929        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5930            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5931          match = true;
5932          break;
5933        }
5934      }
5935      if (!match)
5936        return false;
5937    }
5938
5939    // Static class's protocols, or its super class or category protocols
5940    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
5941    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
5942      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
5943      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
5944      // This is rather dubious but matches gcc's behavior. If lhs has
5945      // no type qualifier and its class has no static protocol(s)
5946      // assume that it is mismatch.
5947      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
5948        return false;
5949      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
5950           LHSInheritedProtocols.begin(),
5951           E = LHSInheritedProtocols.end(); I != E; ++I) {
5952        bool match = false;
5953        ObjCProtocolDecl *lhsProto = (*I);
5954        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
5955             E = rhsQID->qual_end(); J != E; ++J) {
5956          ObjCProtocolDecl *rhsProto = *J;
5957          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
5958              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
5959            match = true;
5960            break;
5961          }
5962        }
5963        if (!match)
5964          return false;
5965      }
5966    }
5967    return true;
5968  }
5969  return false;
5970}
5971
5972/// canAssignObjCInterfaces - Return true if the two interface types are
5973/// compatible for assignment from RHS to LHS.  This handles validation of any
5974/// protocol qualifiers on the LHS or RHS.
5975///
5976bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
5977                                         const ObjCObjectPointerType *RHSOPT) {
5978  const ObjCObjectType* LHS = LHSOPT->getObjectType();
5979  const ObjCObjectType* RHS = RHSOPT->getObjectType();
5980
5981  // If either type represents the built-in 'id' or 'Class' types, return true.
5982  if (LHS->isObjCUnqualifiedIdOrClass() ||
5983      RHS->isObjCUnqualifiedIdOrClass())
5984    return true;
5985
5986  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
5987    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
5988                                             QualType(RHSOPT,0),
5989                                             false);
5990
5991  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
5992    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
5993                                                QualType(RHSOPT,0));
5994
5995  // If we have 2 user-defined types, fall into that path.
5996  if (LHS->getInterface() && RHS->getInterface())
5997    return canAssignObjCInterfaces(LHS, RHS);
5998
5999  return false;
6000}
6001
6002/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
6003/// for providing type-safety for objective-c pointers used to pass/return
6004/// arguments in block literals. When passed as arguments, passing 'A*' where
6005/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
6006/// not OK. For the return type, the opposite is not OK.
6007bool ASTContext::canAssignObjCInterfacesInBlockPointer(
6008                                         const ObjCObjectPointerType *LHSOPT,
6009                                         const ObjCObjectPointerType *RHSOPT,
6010                                         bool BlockReturnType) {
6011  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
6012    return true;
6013
6014  if (LHSOPT->isObjCBuiltinType()) {
6015    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
6016  }
6017
6018  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
6019    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
6020                                             QualType(RHSOPT,0),
6021                                             false);
6022
6023  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
6024  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
6025  if (LHS && RHS)  { // We have 2 user-defined types.
6026    if (LHS != RHS) {
6027      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
6028        return BlockReturnType;
6029      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
6030        return !BlockReturnType;
6031    }
6032    else
6033      return true;
6034  }
6035  return false;
6036}
6037
6038/// getIntersectionOfProtocols - This routine finds the intersection of set
6039/// of protocols inherited from two distinct objective-c pointer objects.
6040/// It is used to build composite qualifier list of the composite type of
6041/// the conditional expression involving two objective-c pointer objects.
6042static
6043void getIntersectionOfProtocols(ASTContext &Context,
6044                                const ObjCObjectPointerType *LHSOPT,
6045                                const ObjCObjectPointerType *RHSOPT,
6046      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
6047
6048  const ObjCObjectType* LHS = LHSOPT->getObjectType();
6049  const ObjCObjectType* RHS = RHSOPT->getObjectType();
6050  assert(LHS->getInterface() && "LHS must have an interface base");
6051  assert(RHS->getInterface() && "RHS must have an interface base");
6052
6053  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
6054  unsigned LHSNumProtocols = LHS->getNumProtocols();
6055  if (LHSNumProtocols > 0)
6056    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
6057  else {
6058    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
6059    Context.CollectInheritedProtocols(LHS->getInterface(),
6060                                      LHSInheritedProtocols);
6061    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
6062                                LHSInheritedProtocols.end());
6063  }
6064
6065  unsigned RHSNumProtocols = RHS->getNumProtocols();
6066  if (RHSNumProtocols > 0) {
6067    ObjCProtocolDecl **RHSProtocols =
6068      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
6069    for (unsigned i = 0; i < RHSNumProtocols; ++i)
6070      if (InheritedProtocolSet.count(RHSProtocols[i]))
6071        IntersectionOfProtocols.push_back(RHSProtocols[i]);
6072  } else {
6073    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
6074    Context.CollectInheritedProtocols(RHS->getInterface(),
6075                                      RHSInheritedProtocols);
6076    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
6077         RHSInheritedProtocols.begin(),
6078         E = RHSInheritedProtocols.end(); I != E; ++I)
6079      if (InheritedProtocolSet.count((*I)))
6080        IntersectionOfProtocols.push_back((*I));
6081  }
6082}
6083
6084/// areCommonBaseCompatible - Returns common base class of the two classes if
6085/// one found. Note that this is O'2 algorithm. But it will be called as the
6086/// last type comparison in a ?-exp of ObjC pointer types before a
6087/// warning is issued. So, its invokation is extremely rare.
6088QualType ASTContext::areCommonBaseCompatible(
6089                                          const ObjCObjectPointerType *Lptr,
6090                                          const ObjCObjectPointerType *Rptr) {
6091  const ObjCObjectType *LHS = Lptr->getObjectType();
6092  const ObjCObjectType *RHS = Rptr->getObjectType();
6093  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
6094  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
6095  if (!LDecl || !RDecl || (declaresSameEntity(LDecl, RDecl)))
6096    return QualType();
6097
6098  do {
6099    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
6100    if (canAssignObjCInterfaces(LHS, RHS)) {
6101      SmallVector<ObjCProtocolDecl *, 8> Protocols;
6102      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
6103
6104      QualType Result = QualType(LHS, 0);
6105      if (!Protocols.empty())
6106        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
6107      Result = getObjCObjectPointerType(Result);
6108      return Result;
6109    }
6110  } while ((LDecl = LDecl->getSuperClass()));
6111
6112  return QualType();
6113}
6114
6115bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
6116                                         const ObjCObjectType *RHS) {
6117  assert(LHS->getInterface() && "LHS is not an interface type");
6118  assert(RHS->getInterface() && "RHS is not an interface type");
6119
6120  // Verify that the base decls are compatible: the RHS must be a subclass of
6121  // the LHS.
6122  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
6123    return false;
6124
6125  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
6126  // protocol qualified at all, then we are good.
6127  if (LHS->getNumProtocols() == 0)
6128    return true;
6129
6130  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't,
6131  // more detailed analysis is required.
6132  if (RHS->getNumProtocols() == 0) {
6133    // OK, if LHS is a superclass of RHS *and*
6134    // this superclass is assignment compatible with LHS.
6135    // false otherwise.
6136    bool IsSuperClass =
6137      LHS->getInterface()->isSuperClassOf(RHS->getInterface());
6138    if (IsSuperClass) {
6139      // OK if conversion of LHS to SuperClass results in narrowing of types
6140      // ; i.e., SuperClass may implement at least one of the protocols
6141      // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
6142      // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
6143      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
6144      CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
6145      // If super class has no protocols, it is not a match.
6146      if (SuperClassInheritedProtocols.empty())
6147        return false;
6148
6149      for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
6150           LHSPE = LHS->qual_end();
6151           LHSPI != LHSPE; LHSPI++) {
6152        bool SuperImplementsProtocol = false;
6153        ObjCProtocolDecl *LHSProto = (*LHSPI);
6154
6155        for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
6156             SuperClassInheritedProtocols.begin(),
6157             E = SuperClassInheritedProtocols.end(); I != E; ++I) {
6158          ObjCProtocolDecl *SuperClassProto = (*I);
6159          if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
6160            SuperImplementsProtocol = true;
6161            break;
6162          }
6163        }
6164        if (!SuperImplementsProtocol)
6165          return false;
6166      }
6167      return true;
6168    }
6169    return false;
6170  }
6171
6172  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
6173                                     LHSPE = LHS->qual_end();
6174       LHSPI != LHSPE; LHSPI++) {
6175    bool RHSImplementsProtocol = false;
6176
6177    // If the RHS doesn't implement the protocol on the left, the types
6178    // are incompatible.
6179    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
6180                                       RHSPE = RHS->qual_end();
6181         RHSPI != RHSPE; RHSPI++) {
6182      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
6183        RHSImplementsProtocol = true;
6184        break;
6185      }
6186    }
6187    // FIXME: For better diagnostics, consider passing back the protocol name.
6188    if (!RHSImplementsProtocol)
6189      return false;
6190  }
6191  // The RHS implements all protocols listed on the LHS.
6192  return true;
6193}
6194
6195bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
6196  // get the "pointed to" types
6197  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
6198  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
6199
6200  if (!LHSOPT || !RHSOPT)
6201    return false;
6202
6203  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
6204         canAssignObjCInterfaces(RHSOPT, LHSOPT);
6205}
6206
6207bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
6208  return canAssignObjCInterfaces(
6209                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
6210                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
6211}
6212
6213/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
6214/// both shall have the identically qualified version of a compatible type.
6215/// C99 6.2.7p1: Two types have compatible types if their types are the
6216/// same. See 6.7.[2,3,5] for additional rules.
6217bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
6218                                    bool CompareUnqualified) {
6219  if (getLangOpts().CPlusPlus)
6220    return hasSameType(LHS, RHS);
6221
6222  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
6223}
6224
6225bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
6226  return typesAreCompatible(LHS, RHS);
6227}
6228
6229bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
6230  return !mergeTypes(LHS, RHS, true).isNull();
6231}
6232
6233/// mergeTransparentUnionType - if T is a transparent union type and a member
6234/// of T is compatible with SubType, return the merged type, else return
6235/// QualType()
6236QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
6237                                               bool OfBlockPointer,
6238                                               bool Unqualified) {
6239  if (const RecordType *UT = T->getAsUnionType()) {
6240    RecordDecl *UD = UT->getDecl();
6241    if (UD->hasAttr<TransparentUnionAttr>()) {
6242      for (RecordDecl::field_iterator it = UD->field_begin(),
6243           itend = UD->field_end(); it != itend; ++it) {
6244        QualType ET = it->getType().getUnqualifiedType();
6245        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
6246        if (!MT.isNull())
6247          return MT;
6248      }
6249    }
6250  }
6251
6252  return QualType();
6253}
6254
6255/// mergeFunctionArgumentTypes - merge two types which appear as function
6256/// argument types
6257QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
6258                                                bool OfBlockPointer,
6259                                                bool Unqualified) {
6260  // GNU extension: two types are compatible if they appear as a function
6261  // argument, one of the types is a transparent union type and the other
6262  // type is compatible with a union member
6263  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
6264                                              Unqualified);
6265  if (!lmerge.isNull())
6266    return lmerge;
6267
6268  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
6269                                              Unqualified);
6270  if (!rmerge.isNull())
6271    return rmerge;
6272
6273  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
6274}
6275
6276QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
6277                                        bool OfBlockPointer,
6278                                        bool Unqualified) {
6279  const FunctionType *lbase = lhs->getAs<FunctionType>();
6280  const FunctionType *rbase = rhs->getAs<FunctionType>();
6281  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
6282  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
6283  bool allLTypes = true;
6284  bool allRTypes = true;
6285
6286  // Check return type
6287  QualType retType;
6288  if (OfBlockPointer) {
6289    QualType RHS = rbase->getResultType();
6290    QualType LHS = lbase->getResultType();
6291    bool UnqualifiedResult = Unqualified;
6292    if (!UnqualifiedResult)
6293      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
6294    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
6295  }
6296  else
6297    retType = mergeTypes(lbase->getResultType(), rbase->getResultType(), false,
6298                         Unqualified);
6299  if (retType.isNull()) return QualType();
6300
6301  if (Unqualified)
6302    retType = retType.getUnqualifiedType();
6303
6304  CanQualType LRetType = getCanonicalType(lbase->getResultType());
6305  CanQualType RRetType = getCanonicalType(rbase->getResultType());
6306  if (Unqualified) {
6307    LRetType = LRetType.getUnqualifiedType();
6308    RRetType = RRetType.getUnqualifiedType();
6309  }
6310
6311  if (getCanonicalType(retType) != LRetType)
6312    allLTypes = false;
6313  if (getCanonicalType(retType) != RRetType)
6314    allRTypes = false;
6315
6316  // FIXME: double check this
6317  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
6318  //                           rbase->getRegParmAttr() != 0 &&
6319  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
6320  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
6321  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
6322
6323  // Compatible functions must have compatible calling conventions
6324  if (!isSameCallConv(lbaseInfo.getCC(), rbaseInfo.getCC()))
6325    return QualType();
6326
6327  // Regparm is part of the calling convention.
6328  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
6329    return QualType();
6330  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
6331    return QualType();
6332
6333  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
6334    return QualType();
6335
6336  // functypes which return are preferred over those that do not.
6337  if (lbaseInfo.getNoReturn() && !rbaseInfo.getNoReturn())
6338    allLTypes = false;
6339  else if (!lbaseInfo.getNoReturn() && rbaseInfo.getNoReturn())
6340    allRTypes = false;
6341  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
6342  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
6343
6344  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
6345
6346  if (lproto && rproto) { // two C99 style function prototypes
6347    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
6348           "C++ shouldn't be here");
6349    unsigned lproto_nargs = lproto->getNumArgs();
6350    unsigned rproto_nargs = rproto->getNumArgs();
6351
6352    // Compatible functions must have the same number of arguments
6353    if (lproto_nargs != rproto_nargs)
6354      return QualType();
6355
6356    // Variadic and non-variadic functions aren't compatible
6357    if (lproto->isVariadic() != rproto->isVariadic())
6358      return QualType();
6359
6360    if (lproto->getTypeQuals() != rproto->getTypeQuals())
6361      return QualType();
6362
6363    if (LangOpts.ObjCAutoRefCount &&
6364        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
6365      return QualType();
6366
6367    // Check argument compatibility
6368    SmallVector<QualType, 10> types;
6369    for (unsigned i = 0; i < lproto_nargs; i++) {
6370      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
6371      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
6372      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
6373                                                    OfBlockPointer,
6374                                                    Unqualified);
6375      if (argtype.isNull()) return QualType();
6376
6377      if (Unqualified)
6378        argtype = argtype.getUnqualifiedType();
6379
6380      types.push_back(argtype);
6381      if (Unqualified) {
6382        largtype = largtype.getUnqualifiedType();
6383        rargtype = rargtype.getUnqualifiedType();
6384      }
6385
6386      if (getCanonicalType(argtype) != getCanonicalType(largtype))
6387        allLTypes = false;
6388      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
6389        allRTypes = false;
6390    }
6391
6392    if (allLTypes) return lhs;
6393    if (allRTypes) return rhs;
6394
6395    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
6396    EPI.ExtInfo = einfo;
6397    return getFunctionType(retType, types.begin(), types.size(), EPI);
6398  }
6399
6400  if (lproto) allRTypes = false;
6401  if (rproto) allLTypes = false;
6402
6403  const FunctionProtoType *proto = lproto ? lproto : rproto;
6404  if (proto) {
6405    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
6406    if (proto->isVariadic()) return QualType();
6407    // Check that the types are compatible with the types that
6408    // would result from default argument promotions (C99 6.7.5.3p15).
6409    // The only types actually affected are promotable integer
6410    // types and floats, which would be passed as a different
6411    // type depending on whether the prototype is visible.
6412    unsigned proto_nargs = proto->getNumArgs();
6413    for (unsigned i = 0; i < proto_nargs; ++i) {
6414      QualType argTy = proto->getArgType(i);
6415
6416      // Look at the converted type of enum types, since that is the type used
6417      // to pass enum values.
6418      if (const EnumType *Enum = argTy->getAs<EnumType>()) {
6419        argTy = Enum->getDecl()->getIntegerType();
6420        if (argTy.isNull())
6421          return QualType();
6422      }
6423
6424      if (argTy->isPromotableIntegerType() ||
6425          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
6426        return QualType();
6427    }
6428
6429    if (allLTypes) return lhs;
6430    if (allRTypes) return rhs;
6431
6432    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
6433    EPI.ExtInfo = einfo;
6434    return getFunctionType(retType, proto->arg_type_begin(),
6435                           proto->getNumArgs(), EPI);
6436  }
6437
6438  if (allLTypes) return lhs;
6439  if (allRTypes) return rhs;
6440  return getFunctionNoProtoType(retType, einfo);
6441}
6442
6443QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
6444                                bool OfBlockPointer,
6445                                bool Unqualified, bool BlockReturnType) {
6446  // C++ [expr]: If an expression initially has the type "reference to T", the
6447  // type is adjusted to "T" prior to any further analysis, the expression
6448  // designates the object or function denoted by the reference, and the
6449  // expression is an lvalue unless the reference is an rvalue reference and
6450  // the expression is a function call (possibly inside parentheses).
6451  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
6452  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
6453
6454  if (Unqualified) {
6455    LHS = LHS.getUnqualifiedType();
6456    RHS = RHS.getUnqualifiedType();
6457  }
6458
6459  QualType LHSCan = getCanonicalType(LHS),
6460           RHSCan = getCanonicalType(RHS);
6461
6462  // If two types are identical, they are compatible.
6463  if (LHSCan == RHSCan)
6464    return LHS;
6465
6466  // If the qualifiers are different, the types aren't compatible... mostly.
6467  Qualifiers LQuals = LHSCan.getLocalQualifiers();
6468  Qualifiers RQuals = RHSCan.getLocalQualifiers();
6469  if (LQuals != RQuals) {
6470    // If any of these qualifiers are different, we have a type
6471    // mismatch.
6472    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
6473        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
6474        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
6475      return QualType();
6476
6477    // Exactly one GC qualifier difference is allowed: __strong is
6478    // okay if the other type has no GC qualifier but is an Objective
6479    // C object pointer (i.e. implicitly strong by default).  We fix
6480    // this by pretending that the unqualified type was actually
6481    // qualified __strong.
6482    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
6483    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
6484    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
6485
6486    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
6487      return QualType();
6488
6489    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
6490      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
6491    }
6492    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
6493      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
6494    }
6495    return QualType();
6496  }
6497
6498  // Okay, qualifiers are equal.
6499
6500  Type::TypeClass LHSClass = LHSCan->getTypeClass();
6501  Type::TypeClass RHSClass = RHSCan->getTypeClass();
6502
6503  // We want to consider the two function types to be the same for these
6504  // comparisons, just force one to the other.
6505  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
6506  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
6507
6508  // Same as above for arrays
6509  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
6510    LHSClass = Type::ConstantArray;
6511  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
6512    RHSClass = Type::ConstantArray;
6513
6514  // ObjCInterfaces are just specialized ObjCObjects.
6515  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
6516  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
6517
6518  // Canonicalize ExtVector -> Vector.
6519  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
6520  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
6521
6522  // If the canonical type classes don't match.
6523  if (LHSClass != RHSClass) {
6524    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
6525    // a signed integer type, or an unsigned integer type.
6526    // Compatibility is based on the underlying type, not the promotion
6527    // type.
6528    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
6529      QualType TINT = ETy->getDecl()->getIntegerType();
6530      if (!TINT.isNull() && hasSameType(TINT, RHSCan.getUnqualifiedType()))
6531        return RHS;
6532    }
6533    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
6534      QualType TINT = ETy->getDecl()->getIntegerType();
6535      if (!TINT.isNull() && hasSameType(TINT, LHSCan.getUnqualifiedType()))
6536        return LHS;
6537    }
6538    // allow block pointer type to match an 'id' type.
6539    if (OfBlockPointer && !BlockReturnType) {
6540       if (LHS->isObjCIdType() && RHS->isBlockPointerType())
6541         return LHS;
6542      if (RHS->isObjCIdType() && LHS->isBlockPointerType())
6543        return RHS;
6544    }
6545
6546    return QualType();
6547  }
6548
6549  // The canonical type classes match.
6550  switch (LHSClass) {
6551#define TYPE(Class, Base)
6552#define ABSTRACT_TYPE(Class, Base)
6553#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
6554#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
6555#define DEPENDENT_TYPE(Class, Base) case Type::Class:
6556#include "clang/AST/TypeNodes.def"
6557    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
6558
6559  case Type::LValueReference:
6560  case Type::RValueReference:
6561  case Type::MemberPointer:
6562    llvm_unreachable("C++ should never be in mergeTypes");
6563
6564  case Type::ObjCInterface:
6565  case Type::IncompleteArray:
6566  case Type::VariableArray:
6567  case Type::FunctionProto:
6568  case Type::ExtVector:
6569    llvm_unreachable("Types are eliminated above");
6570
6571  case Type::Pointer:
6572  {
6573    // Merge two pointer types, while trying to preserve typedef info
6574    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
6575    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
6576    if (Unqualified) {
6577      LHSPointee = LHSPointee.getUnqualifiedType();
6578      RHSPointee = RHSPointee.getUnqualifiedType();
6579    }
6580    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
6581                                     Unqualified);
6582    if (ResultType.isNull()) return QualType();
6583    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
6584      return LHS;
6585    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
6586      return RHS;
6587    return getPointerType(ResultType);
6588  }
6589  case Type::BlockPointer:
6590  {
6591    // Merge two block pointer types, while trying to preserve typedef info
6592    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
6593    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
6594    if (Unqualified) {
6595      LHSPointee = LHSPointee.getUnqualifiedType();
6596      RHSPointee = RHSPointee.getUnqualifiedType();
6597    }
6598    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
6599                                     Unqualified);
6600    if (ResultType.isNull()) return QualType();
6601    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
6602      return LHS;
6603    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
6604      return RHS;
6605    return getBlockPointerType(ResultType);
6606  }
6607  case Type::Atomic:
6608  {
6609    // Merge two pointer types, while trying to preserve typedef info
6610    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
6611    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
6612    if (Unqualified) {
6613      LHSValue = LHSValue.getUnqualifiedType();
6614      RHSValue = RHSValue.getUnqualifiedType();
6615    }
6616    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
6617                                     Unqualified);
6618    if (ResultType.isNull()) return QualType();
6619    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
6620      return LHS;
6621    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
6622      return RHS;
6623    return getAtomicType(ResultType);
6624  }
6625  case Type::ConstantArray:
6626  {
6627    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
6628    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
6629    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
6630      return QualType();
6631
6632    QualType LHSElem = getAsArrayType(LHS)->getElementType();
6633    QualType RHSElem = getAsArrayType(RHS)->getElementType();
6634    if (Unqualified) {
6635      LHSElem = LHSElem.getUnqualifiedType();
6636      RHSElem = RHSElem.getUnqualifiedType();
6637    }
6638
6639    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
6640    if (ResultType.isNull()) return QualType();
6641    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
6642      return LHS;
6643    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
6644      return RHS;
6645    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
6646                                          ArrayType::ArraySizeModifier(), 0);
6647    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
6648                                          ArrayType::ArraySizeModifier(), 0);
6649    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
6650    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
6651    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
6652      return LHS;
6653    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
6654      return RHS;
6655    if (LVAT) {
6656      // FIXME: This isn't correct! But tricky to implement because
6657      // the array's size has to be the size of LHS, but the type
6658      // has to be different.
6659      return LHS;
6660    }
6661    if (RVAT) {
6662      // FIXME: This isn't correct! But tricky to implement because
6663      // the array's size has to be the size of RHS, but the type
6664      // has to be different.
6665      return RHS;
6666    }
6667    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
6668    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
6669    return getIncompleteArrayType(ResultType,
6670                                  ArrayType::ArraySizeModifier(), 0);
6671  }
6672  case Type::FunctionNoProto:
6673    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
6674  case Type::Record:
6675  case Type::Enum:
6676    return QualType();
6677  case Type::Builtin:
6678    // Only exactly equal builtin types are compatible, which is tested above.
6679    return QualType();
6680  case Type::Complex:
6681    // Distinct complex types are incompatible.
6682    return QualType();
6683  case Type::Vector:
6684    // FIXME: The merged type should be an ExtVector!
6685    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
6686                             RHSCan->getAs<VectorType>()))
6687      return LHS;
6688    return QualType();
6689  case Type::ObjCObject: {
6690    // Check if the types are assignment compatible.
6691    // FIXME: This should be type compatibility, e.g. whether
6692    // "LHS x; RHS x;" at global scope is legal.
6693    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
6694    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
6695    if (canAssignObjCInterfaces(LHSIface, RHSIface))
6696      return LHS;
6697
6698    return QualType();
6699  }
6700  case Type::ObjCObjectPointer: {
6701    if (OfBlockPointer) {
6702      if (canAssignObjCInterfacesInBlockPointer(
6703                                          LHS->getAs<ObjCObjectPointerType>(),
6704                                          RHS->getAs<ObjCObjectPointerType>(),
6705                                          BlockReturnType))
6706        return LHS;
6707      return QualType();
6708    }
6709    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
6710                                RHS->getAs<ObjCObjectPointerType>()))
6711      return LHS;
6712
6713    return QualType();
6714  }
6715  }
6716
6717  llvm_unreachable("Invalid Type::Class!");
6718}
6719
6720bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
6721                   const FunctionProtoType *FromFunctionType,
6722                   const FunctionProtoType *ToFunctionType) {
6723  if (FromFunctionType->hasAnyConsumedArgs() !=
6724      ToFunctionType->hasAnyConsumedArgs())
6725    return false;
6726  FunctionProtoType::ExtProtoInfo FromEPI =
6727    FromFunctionType->getExtProtoInfo();
6728  FunctionProtoType::ExtProtoInfo ToEPI =
6729    ToFunctionType->getExtProtoInfo();
6730  if (FromEPI.ConsumedArguments && ToEPI.ConsumedArguments)
6731    for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs();
6732         ArgIdx != NumArgs; ++ArgIdx)  {
6733      if (FromEPI.ConsumedArguments[ArgIdx] !=
6734          ToEPI.ConsumedArguments[ArgIdx])
6735        return false;
6736    }
6737  return true;
6738}
6739
6740/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
6741/// 'RHS' attributes and returns the merged version; including for function
6742/// return types.
6743QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
6744  QualType LHSCan = getCanonicalType(LHS),
6745  RHSCan = getCanonicalType(RHS);
6746  // If two types are identical, they are compatible.
6747  if (LHSCan == RHSCan)
6748    return LHS;
6749  if (RHSCan->isFunctionType()) {
6750    if (!LHSCan->isFunctionType())
6751      return QualType();
6752    QualType OldReturnType =
6753      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
6754    QualType NewReturnType =
6755      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
6756    QualType ResReturnType =
6757      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
6758    if (ResReturnType.isNull())
6759      return QualType();
6760    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
6761      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
6762      // In either case, use OldReturnType to build the new function type.
6763      const FunctionType *F = LHS->getAs<FunctionType>();
6764      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
6765        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
6766        EPI.ExtInfo = getFunctionExtInfo(LHS);
6767        QualType ResultType
6768          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
6769                            FPT->getNumArgs(), EPI);
6770        return ResultType;
6771      }
6772    }
6773    return QualType();
6774  }
6775
6776  // If the qualifiers are different, the types can still be merged.
6777  Qualifiers LQuals = LHSCan.getLocalQualifiers();
6778  Qualifiers RQuals = RHSCan.getLocalQualifiers();
6779  if (LQuals != RQuals) {
6780    // If any of these qualifiers are different, we have a type mismatch.
6781    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
6782        LQuals.getAddressSpace() != RQuals.getAddressSpace())
6783      return QualType();
6784
6785    // Exactly one GC qualifier difference is allowed: __strong is
6786    // okay if the other type has no GC qualifier but is an Objective
6787    // C object pointer (i.e. implicitly strong by default).  We fix
6788    // this by pretending that the unqualified type was actually
6789    // qualified __strong.
6790    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
6791    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
6792    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
6793
6794    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
6795      return QualType();
6796
6797    if (GC_L == Qualifiers::Strong)
6798      return LHS;
6799    if (GC_R == Qualifiers::Strong)
6800      return RHS;
6801    return QualType();
6802  }
6803
6804  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
6805    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6806    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
6807    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
6808    if (ResQT == LHSBaseQT)
6809      return LHS;
6810    if (ResQT == RHSBaseQT)
6811      return RHS;
6812  }
6813  return QualType();
6814}
6815
6816//===----------------------------------------------------------------------===//
6817//                         Integer Predicates
6818//===----------------------------------------------------------------------===//
6819
6820unsigned ASTContext::getIntWidth(QualType T) const {
6821  if (const EnumType *ET = dyn_cast<EnumType>(T))
6822    T = ET->getDecl()->getIntegerType();
6823  if (T->isBooleanType())
6824    return 1;
6825  // For builtin types, just use the standard type sizing method
6826  return (unsigned)getTypeSize(T);
6827}
6828
6829QualType ASTContext::getCorrespondingUnsignedType(QualType T) {
6830  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
6831
6832  // Turn <4 x signed int> -> <4 x unsigned int>
6833  if (const VectorType *VTy = T->getAs<VectorType>())
6834    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
6835                         VTy->getNumElements(), VTy->getVectorKind());
6836
6837  // For enums, we return the unsigned version of the base type.
6838  if (const EnumType *ETy = T->getAs<EnumType>())
6839    T = ETy->getDecl()->getIntegerType();
6840
6841  const BuiltinType *BTy = T->getAs<BuiltinType>();
6842  assert(BTy && "Unexpected signed integer type");
6843  switch (BTy->getKind()) {
6844  case BuiltinType::Char_S:
6845  case BuiltinType::SChar:
6846    return UnsignedCharTy;
6847  case BuiltinType::Short:
6848    return UnsignedShortTy;
6849  case BuiltinType::Int:
6850    return UnsignedIntTy;
6851  case BuiltinType::Long:
6852    return UnsignedLongTy;
6853  case BuiltinType::LongLong:
6854    return UnsignedLongLongTy;
6855  case BuiltinType::Int128:
6856    return UnsignedInt128Ty;
6857  default:
6858    llvm_unreachable("Unexpected signed integer type");
6859  }
6860}
6861
6862ASTMutationListener::~ASTMutationListener() { }
6863
6864
6865//===----------------------------------------------------------------------===//
6866//                          Builtin Type Computation
6867//===----------------------------------------------------------------------===//
6868
6869/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
6870/// pointer over the consumed characters.  This returns the resultant type.  If
6871/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
6872/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
6873/// a vector of "i*".
6874///
6875/// RequiresICE is filled in on return to indicate whether the value is required
6876/// to be an Integer Constant Expression.
6877static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
6878                                  ASTContext::GetBuiltinTypeError &Error,
6879                                  bool &RequiresICE,
6880                                  bool AllowTypeModifiers) {
6881  // Modifiers.
6882  int HowLong = 0;
6883  bool Signed = false, Unsigned = false;
6884  RequiresICE = false;
6885
6886  // Read the prefixed modifiers first.
6887  bool Done = false;
6888  while (!Done) {
6889    switch (*Str++) {
6890    default: Done = true; --Str; break;
6891    case 'I':
6892      RequiresICE = true;
6893      break;
6894    case 'S':
6895      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
6896      assert(!Signed && "Can't use 'S' modifier multiple times!");
6897      Signed = true;
6898      break;
6899    case 'U':
6900      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
6901      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
6902      Unsigned = true;
6903      break;
6904    case 'L':
6905      assert(HowLong <= 2 && "Can't have LLLL modifier");
6906      ++HowLong;
6907      break;
6908    }
6909  }
6910
6911  QualType Type;
6912
6913  // Read the base type.
6914  switch (*Str++) {
6915  default: llvm_unreachable("Unknown builtin type letter!");
6916  case 'v':
6917    assert(HowLong == 0 && !Signed && !Unsigned &&
6918           "Bad modifiers used with 'v'!");
6919    Type = Context.VoidTy;
6920    break;
6921  case 'f':
6922    assert(HowLong == 0 && !Signed && !Unsigned &&
6923           "Bad modifiers used with 'f'!");
6924    Type = Context.FloatTy;
6925    break;
6926  case 'd':
6927    assert(HowLong < 2 && !Signed && !Unsigned &&
6928           "Bad modifiers used with 'd'!");
6929    if (HowLong)
6930      Type = Context.LongDoubleTy;
6931    else
6932      Type = Context.DoubleTy;
6933    break;
6934  case 's':
6935    assert(HowLong == 0 && "Bad modifiers used with 's'!");
6936    if (Unsigned)
6937      Type = Context.UnsignedShortTy;
6938    else
6939      Type = Context.ShortTy;
6940    break;
6941  case 'i':
6942    if (HowLong == 3)
6943      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
6944    else if (HowLong == 2)
6945      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
6946    else if (HowLong == 1)
6947      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
6948    else
6949      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
6950    break;
6951  case 'c':
6952    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
6953    if (Signed)
6954      Type = Context.SignedCharTy;
6955    else if (Unsigned)
6956      Type = Context.UnsignedCharTy;
6957    else
6958      Type = Context.CharTy;
6959    break;
6960  case 'b': // boolean
6961    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
6962    Type = Context.BoolTy;
6963    break;
6964  case 'z':  // size_t.
6965    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
6966    Type = Context.getSizeType();
6967    break;
6968  case 'F':
6969    Type = Context.getCFConstantStringType();
6970    break;
6971  case 'G':
6972    Type = Context.getObjCIdType();
6973    break;
6974  case 'H':
6975    Type = Context.getObjCSelType();
6976    break;
6977  case 'a':
6978    Type = Context.getBuiltinVaListType();
6979    assert(!Type.isNull() && "builtin va list type not initialized!");
6980    break;
6981  case 'A':
6982    // This is a "reference" to a va_list; however, what exactly
6983    // this means depends on how va_list is defined. There are two
6984    // different kinds of va_list: ones passed by value, and ones
6985    // passed by reference.  An example of a by-value va_list is
6986    // x86, where va_list is a char*. An example of by-ref va_list
6987    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
6988    // we want this argument to be a char*&; for x86-64, we want
6989    // it to be a __va_list_tag*.
6990    Type = Context.getBuiltinVaListType();
6991    assert(!Type.isNull() && "builtin va list type not initialized!");
6992    if (Type->isArrayType())
6993      Type = Context.getArrayDecayedType(Type);
6994    else
6995      Type = Context.getLValueReferenceType(Type);
6996    break;
6997  case 'V': {
6998    char *End;
6999    unsigned NumElements = strtoul(Str, &End, 10);
7000    assert(End != Str && "Missing vector size");
7001    Str = End;
7002
7003    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
7004                                             RequiresICE, false);
7005    assert(!RequiresICE && "Can't require vector ICE");
7006
7007    // TODO: No way to make AltiVec vectors in builtins yet.
7008    Type = Context.getVectorType(ElementType, NumElements,
7009                                 VectorType::GenericVector);
7010    break;
7011  }
7012  case 'E': {
7013    char *End;
7014
7015    unsigned NumElements = strtoul(Str, &End, 10);
7016    assert(End != Str && "Missing vector size");
7017
7018    Str = End;
7019
7020    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
7021                                             false);
7022    Type = Context.getExtVectorType(ElementType, NumElements);
7023    break;
7024  }
7025  case 'X': {
7026    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
7027                                             false);
7028    assert(!RequiresICE && "Can't require complex ICE");
7029    Type = Context.getComplexType(ElementType);
7030    break;
7031  }
7032  case 'Y' : {
7033    Type = Context.getPointerDiffType();
7034    break;
7035  }
7036  case 'P':
7037    Type = Context.getFILEType();
7038    if (Type.isNull()) {
7039      Error = ASTContext::GE_Missing_stdio;
7040      return QualType();
7041    }
7042    break;
7043  case 'J':
7044    if (Signed)
7045      Type = Context.getsigjmp_bufType();
7046    else
7047      Type = Context.getjmp_bufType();
7048
7049    if (Type.isNull()) {
7050      Error = ASTContext::GE_Missing_setjmp;
7051      return QualType();
7052    }
7053    break;
7054  case 'K':
7055    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'K'!");
7056    Type = Context.getucontext_tType();
7057
7058    if (Type.isNull()) {
7059      Error = ASTContext::GE_Missing_ucontext;
7060      return QualType();
7061    }
7062    break;
7063  }
7064
7065  // If there are modifiers and if we're allowed to parse them, go for it.
7066  Done = !AllowTypeModifiers;
7067  while (!Done) {
7068    switch (char c = *Str++) {
7069    default: Done = true; --Str; break;
7070    case '*':
7071    case '&': {
7072      // Both pointers and references can have their pointee types
7073      // qualified with an address space.
7074      char *End;
7075      unsigned AddrSpace = strtoul(Str, &End, 10);
7076      if (End != Str && AddrSpace != 0) {
7077        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
7078        Str = End;
7079      }
7080      if (c == '*')
7081        Type = Context.getPointerType(Type);
7082      else
7083        Type = Context.getLValueReferenceType(Type);
7084      break;
7085    }
7086    // FIXME: There's no way to have a built-in with an rvalue ref arg.
7087    case 'C':
7088      Type = Type.withConst();
7089      break;
7090    case 'D':
7091      Type = Context.getVolatileType(Type);
7092      break;
7093    case 'R':
7094      Type = Type.withRestrict();
7095      break;
7096    }
7097  }
7098
7099  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
7100         "Integer constant 'I' type must be an integer");
7101
7102  return Type;
7103}
7104
7105/// GetBuiltinType - Return the type for the specified builtin.
7106QualType ASTContext::GetBuiltinType(unsigned Id,
7107                                    GetBuiltinTypeError &Error,
7108                                    unsigned *IntegerConstantArgs) const {
7109  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
7110
7111  SmallVector<QualType, 8> ArgTypes;
7112
7113  bool RequiresICE = false;
7114  Error = GE_None;
7115  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
7116                                       RequiresICE, true);
7117  if (Error != GE_None)
7118    return QualType();
7119
7120  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
7121
7122  while (TypeStr[0] && TypeStr[0] != '.') {
7123    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
7124    if (Error != GE_None)
7125      return QualType();
7126
7127    // If this argument is required to be an IntegerConstantExpression and the
7128    // caller cares, fill in the bitmask we return.
7129    if (RequiresICE && IntegerConstantArgs)
7130      *IntegerConstantArgs |= 1 << ArgTypes.size();
7131
7132    // Do array -> pointer decay.  The builtin should use the decayed type.
7133    if (Ty->isArrayType())
7134      Ty = getArrayDecayedType(Ty);
7135
7136    ArgTypes.push_back(Ty);
7137  }
7138
7139  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
7140         "'.' should only occur at end of builtin type list!");
7141
7142  FunctionType::ExtInfo EI;
7143  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
7144
7145  bool Variadic = (TypeStr[0] == '.');
7146
7147  // We really shouldn't be making a no-proto type here, especially in C++.
7148  if (ArgTypes.empty() && Variadic)
7149    return getFunctionNoProtoType(ResType, EI);
7150
7151  FunctionProtoType::ExtProtoInfo EPI;
7152  EPI.ExtInfo = EI;
7153  EPI.Variadic = Variadic;
7154
7155  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(), EPI);
7156}
7157
7158GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
7159  GVALinkage External = GVA_StrongExternal;
7160
7161  Linkage L = FD->getLinkage();
7162  switch (L) {
7163  case NoLinkage:
7164  case InternalLinkage:
7165  case UniqueExternalLinkage:
7166    return GVA_Internal;
7167
7168  case ExternalLinkage:
7169    switch (FD->getTemplateSpecializationKind()) {
7170    case TSK_Undeclared:
7171    case TSK_ExplicitSpecialization:
7172      External = GVA_StrongExternal;
7173      break;
7174
7175    case TSK_ExplicitInstantiationDefinition:
7176      return GVA_ExplicitTemplateInstantiation;
7177
7178    case TSK_ExplicitInstantiationDeclaration:
7179    case TSK_ImplicitInstantiation:
7180      External = GVA_TemplateInstantiation;
7181      break;
7182    }
7183  }
7184
7185  if (!FD->isInlined())
7186    return External;
7187
7188  if (!getLangOpts().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
7189    // GNU or C99 inline semantics. Determine whether this symbol should be
7190    // externally visible.
7191    if (FD->isInlineDefinitionExternallyVisible())
7192      return External;
7193
7194    // C99 inline semantics, where the symbol is not externally visible.
7195    return GVA_C99Inline;
7196  }
7197
7198  // C++0x [temp.explicit]p9:
7199  //   [ Note: The intent is that an inline function that is the subject of
7200  //   an explicit instantiation declaration will still be implicitly
7201  //   instantiated when used so that the body can be considered for
7202  //   inlining, but that no out-of-line copy of the inline function would be
7203  //   generated in the translation unit. -- end note ]
7204  if (FD->getTemplateSpecializationKind()
7205                                       == TSK_ExplicitInstantiationDeclaration)
7206    return GVA_C99Inline;
7207
7208  return GVA_CXXInline;
7209}
7210
7211GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
7212  // If this is a static data member, compute the kind of template
7213  // specialization. Otherwise, this variable is not part of a
7214  // template.
7215  TemplateSpecializationKind TSK = TSK_Undeclared;
7216  if (VD->isStaticDataMember())
7217    TSK = VD->getTemplateSpecializationKind();
7218
7219  Linkage L = VD->getLinkage();
7220  if (L == ExternalLinkage && getLangOpts().CPlusPlus &&
7221      VD->getType()->getLinkage() == UniqueExternalLinkage)
7222    L = UniqueExternalLinkage;
7223
7224  switch (L) {
7225  case NoLinkage:
7226  case InternalLinkage:
7227  case UniqueExternalLinkage:
7228    return GVA_Internal;
7229
7230  case ExternalLinkage:
7231    switch (TSK) {
7232    case TSK_Undeclared:
7233    case TSK_ExplicitSpecialization:
7234      return GVA_StrongExternal;
7235
7236    case TSK_ExplicitInstantiationDeclaration:
7237      llvm_unreachable("Variable should not be instantiated");
7238      // Fall through to treat this like any other instantiation.
7239
7240    case TSK_ExplicitInstantiationDefinition:
7241      return GVA_ExplicitTemplateInstantiation;
7242
7243    case TSK_ImplicitInstantiation:
7244      return GVA_TemplateInstantiation;
7245    }
7246  }
7247
7248  llvm_unreachable("Invalid Linkage!");
7249}
7250
7251bool ASTContext::DeclMustBeEmitted(const Decl *D) {
7252  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
7253    if (!VD->isFileVarDecl())
7254      return false;
7255  } else if (!isa<FunctionDecl>(D))
7256    return false;
7257
7258  // Weak references don't produce any output by themselves.
7259  if (D->hasAttr<WeakRefAttr>())
7260    return false;
7261
7262  // Aliases and used decls are required.
7263  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
7264    return true;
7265
7266  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
7267    // Forward declarations aren't required.
7268    if (!FD->doesThisDeclarationHaveABody())
7269      return FD->doesDeclarationForceExternallyVisibleDefinition();
7270
7271    // Constructors and destructors are required.
7272    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
7273      return true;
7274
7275    // The key function for a class is required.
7276    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
7277      const CXXRecordDecl *RD = MD->getParent();
7278      if (MD->isOutOfLine() && RD->isDynamicClass()) {
7279        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
7280        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
7281          return true;
7282      }
7283    }
7284
7285    GVALinkage Linkage = GetGVALinkageForFunction(FD);
7286
7287    // static, static inline, always_inline, and extern inline functions can
7288    // always be deferred.  Normal inline functions can be deferred in C99/C++.
7289    // Implicit template instantiations can also be deferred in C++.
7290    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
7291        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
7292      return false;
7293    return true;
7294  }
7295
7296  const VarDecl *VD = cast<VarDecl>(D);
7297  assert(VD->isFileVarDecl() && "Expected file scoped var");
7298
7299  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
7300    return false;
7301
7302  // Structs that have non-trivial constructors or destructors are required.
7303
7304  // FIXME: Handle references.
7305  // FIXME: Be more selective about which constructors we care about.
7306  if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
7307    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
7308      if (RD->hasDefinition() && !(RD->hasTrivialDefaultConstructor() &&
7309                                   RD->hasTrivialCopyConstructor() &&
7310                                   RD->hasTrivialMoveConstructor() &&
7311                                   RD->hasTrivialDestructor()))
7312        return true;
7313    }
7314  }
7315
7316  GVALinkage L = GetGVALinkageForVariable(VD);
7317  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
7318    if (!(VD->getInit() && VD->getInit()->HasSideEffects(*this)))
7319      return false;
7320  }
7321
7322  return true;
7323}
7324
7325CallingConv ASTContext::getDefaultCXXMethodCallConv(bool isVariadic) {
7326  // Pass through to the C++ ABI object
7327  return ABI->getDefaultMethodCallConv(isVariadic);
7328}
7329
7330CallingConv ASTContext::getCanonicalCallConv(CallingConv CC) const {
7331  if (CC == CC_C && !LangOpts.MRTD && getTargetInfo().getCXXABI() != CXXABI_Microsoft)
7332    return CC_Default;
7333  return CC;
7334}
7335
7336bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
7337  // Pass through to the C++ ABI object
7338  return ABI->isNearlyEmpty(RD);
7339}
7340
7341MangleContext *ASTContext::createMangleContext() {
7342  switch (Target->getCXXABI()) {
7343  case CXXABI_ARM:
7344  case CXXABI_Itanium:
7345    return createItaniumMangleContext(*this, getDiagnostics());
7346  case CXXABI_Microsoft:
7347    return createMicrosoftMangleContext(*this, getDiagnostics());
7348  }
7349  llvm_unreachable("Unsupported ABI");
7350}
7351
7352CXXABI::~CXXABI() {}
7353
7354size_t ASTContext::getSideTableAllocatedMemory() const {
7355  return ASTRecordLayouts.getMemorySize()
7356    + llvm::capacity_in_bytes(ObjCLayouts)
7357    + llvm::capacity_in_bytes(KeyFunctions)
7358    + llvm::capacity_in_bytes(ObjCImpls)
7359    + llvm::capacity_in_bytes(BlockVarCopyInits)
7360    + llvm::capacity_in_bytes(DeclAttrs)
7361    + llvm::capacity_in_bytes(InstantiatedFromStaticDataMember)
7362    + llvm::capacity_in_bytes(InstantiatedFromUsingDecl)
7363    + llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl)
7364    + llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl)
7365    + llvm::capacity_in_bytes(OverriddenMethods)
7366    + llvm::capacity_in_bytes(Types)
7367    + llvm::capacity_in_bytes(VariableArrayTypes)
7368    + llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
7369}
7370
7371unsigned ASTContext::getLambdaManglingNumber(CXXMethodDecl *CallOperator) {
7372  CXXRecordDecl *Lambda = CallOperator->getParent();
7373  return LambdaMangleContexts[Lambda->getDeclContext()]
7374           .getManglingNumber(CallOperator);
7375}
7376
7377
7378void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
7379  ParamIndices[D] = index;
7380}
7381
7382unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
7383  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
7384  assert(I != ParamIndices.end() &&
7385         "ParmIndices lacks entry set by ParmVarDecl");
7386  return I->second;
7387}
7388