ASTContext.cpp revision f7992132207d7ddc8810a135cec97ebe5805e500 
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 "CXXABI.h"
16#include "clang/AST/ASTMutationListener.h"
17#include "clang/AST/Attr.h"
18#include "clang/AST/CharUnits.h"
19#include "clang/AST/Comment.h"
20#include "clang/AST/CommentCommandTraits.h"
21#include "clang/AST/DeclCXX.h"
22#include "clang/AST/DeclObjC.h"
23#include "clang/AST/DeclTemplate.h"
24#include "clang/AST/Expr.h"
25#include "clang/AST/ExprCXX.h"
26#include "clang/AST/ExternalASTSource.h"
27#include "clang/AST/Mangle.h"
28#include "clang/AST/RecordLayout.h"
29#include "clang/AST/TypeLoc.h"
30#include "clang/Basic/Builtins.h"
31#include "clang/Basic/SourceManager.h"
32#include "clang/Basic/TargetInfo.h"
33#include "llvm/ADT/SmallString.h"
34#include "llvm/ADT/StringExtras.h"
35#include "llvm/Support/Capacity.h"
36#include "llvm/Support/MathExtras.h"
37#include "llvm/Support/raw_ostream.h"
38#include <map>
39
40using namespace clang;
41
42unsigned ASTContext::NumImplicitDefaultConstructors;
43unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
44unsigned ASTContext::NumImplicitCopyConstructors;
45unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
46unsigned ASTContext::NumImplicitMoveConstructors;
47unsigned ASTContext::NumImplicitMoveConstructorsDeclared;
48unsigned ASTContext::NumImplicitCopyAssignmentOperators;
49unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
50unsigned ASTContext::NumImplicitMoveAssignmentOperators;
51unsigned ASTContext::NumImplicitMoveAssignmentOperatorsDeclared;
52unsigned ASTContext::NumImplicitDestructors;
53unsigned ASTContext::NumImplicitDestructorsDeclared;
54
55enum FloatingRank {
56  HalfRank, FloatRank, DoubleRank, LongDoubleRank
57};
58
59RawComment *ASTContext::getRawCommentForDeclNoCache(const Decl *D) const {
60  if (!CommentsLoaded && ExternalSource) {
61    ExternalSource->ReadComments();
62    CommentsLoaded = true;
63  }
64
65  assert(D);
66
67  // User can not attach documentation to implicit declarations.
68  if (D->isImplicit())
69    return NULL;
70
71  // User can not attach documentation to implicit instantiations.
72  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
73    if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
74      return NULL;
75  }
76
77  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
78    if (VD->isStaticDataMember() &&
79        VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
80      return NULL;
81  }
82
83  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(D)) {
84    if (CRD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
85      return NULL;
86  }
87
88  if (const EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
89    if (ED->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
90      return NULL;
91  }
92
93  // TODO: handle comments for function parameters properly.
94  if (isa<ParmVarDecl>(D))
95    return NULL;
96
97  // TODO: we could look up template parameter documentation in the template
98  // documentation.
99  if (isa<TemplateTypeParmDecl>(D) ||
100      isa<NonTypeTemplateParmDecl>(D) ||
101      isa<TemplateTemplateParmDecl>(D))
102    return NULL;
103
104  ArrayRef<RawComment *> RawComments = Comments.getComments();
105
106  // If there are no comments anywhere, we won't find anything.
107  if (RawComments.empty())
108    return NULL;
109
110  // Find declaration location.
111  // For Objective-C declarations we generally don't expect to have multiple
112  // declarators, thus use declaration starting location as the "declaration
113  // location".
114  // For all other declarations multiple declarators are used quite frequently,
115  // so we use the location of the identifier as the "declaration location".
116  SourceLocation DeclLoc;
117  if (isa<ObjCMethodDecl>(D) || isa<ObjCContainerDecl>(D) ||
118      isa<ObjCPropertyDecl>(D) ||
119      isa<RedeclarableTemplateDecl>(D) ||
120      isa<ClassTemplateSpecializationDecl>(D))
121    DeclLoc = D->getLocStart();
122  else
123    DeclLoc = D->getLocation();
124
125  // If the declaration doesn't map directly to a location in a file, we
126  // can't find the comment.
127  if (DeclLoc.isInvalid() || !DeclLoc.isFileID())
128    return NULL;
129
130  // Find the comment that occurs just after this declaration.
131  ArrayRef<RawComment *>::iterator Comment;
132  {
133    // When searching for comments during parsing, the comment we are looking
134    // for is usually among the last two comments we parsed -- check them
135    // first.
136    RawComment CommentAtDeclLoc(SourceMgr, SourceRange(DeclLoc));
137    BeforeThanCompare<RawComment> Compare(SourceMgr);
138    ArrayRef<RawComment *>::iterator MaybeBeforeDecl = RawComments.end() - 1;
139    bool Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
140    if (!Found && RawComments.size() >= 2) {
141      MaybeBeforeDecl--;
142      Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
143    }
144
145    if (Found) {
146      Comment = MaybeBeforeDecl + 1;
147      assert(Comment == std::lower_bound(RawComments.begin(), RawComments.end(),
148                                         &CommentAtDeclLoc, Compare));
149    } else {
150      // Slow path.
151      Comment = std::lower_bound(RawComments.begin(), RawComments.end(),
152                                 &CommentAtDeclLoc, Compare);
153    }
154  }
155
156  // Decompose the location for the declaration and find the beginning of the
157  // file buffer.
158  std::pair<FileID, unsigned> DeclLocDecomp = SourceMgr.getDecomposedLoc(DeclLoc);
159
160  // First check whether we have a trailing comment.
161  if (Comment != RawComments.end() &&
162      (*Comment)->isDocumentation() && (*Comment)->isTrailingComment() &&
163      (isa<FieldDecl>(D) || isa<EnumConstantDecl>(D) || isa<VarDecl>(D))) {
164    std::pair<FileID, unsigned> CommentBeginDecomp
165      = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getBegin());
166    // Check that Doxygen trailing comment comes after the declaration, starts
167    // on the same line and in the same file as the declaration.
168    if (DeclLocDecomp.first == CommentBeginDecomp.first &&
169        SourceMgr.getLineNumber(DeclLocDecomp.first, DeclLocDecomp.second)
170          == SourceMgr.getLineNumber(CommentBeginDecomp.first,
171                                     CommentBeginDecomp.second)) {
172      return *Comment;
173    }
174  }
175
176  // The comment just after the declaration was not a trailing comment.
177  // Let's look at the previous comment.
178  if (Comment == RawComments.begin())
179    return NULL;
180  --Comment;
181
182  // Check that we actually have a non-member Doxygen comment.
183  if (!(*Comment)->isDocumentation() || (*Comment)->isTrailingComment())
184    return NULL;
185
186  // Decompose the end of the comment.
187  std::pair<FileID, unsigned> CommentEndDecomp
188    = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getEnd());
189
190  // If the comment and the declaration aren't in the same file, then they
191  // aren't related.
192  if (DeclLocDecomp.first != CommentEndDecomp.first)
193    return NULL;
194
195  // Get the corresponding buffer.
196  bool Invalid = false;
197  const char *Buffer = SourceMgr.getBufferData(DeclLocDecomp.first,
198                                               &Invalid).data();
199  if (Invalid)
200    return NULL;
201
202  // Extract text between the comment and declaration.
203  StringRef Text(Buffer + CommentEndDecomp.second,
204                 DeclLocDecomp.second - CommentEndDecomp.second);
205
206  // There should be no other declarations or preprocessor directives between
207  // comment and declaration.
208  if (Text.find_first_of(",;{}#@") != StringRef::npos)
209    return NULL;
210
211  return *Comment;
212}
213
214namespace {
215/// If we have a 'templated' declaration for a template, adjust 'D' to
216/// refer to the actual template.
217/// If we have an implicit instantiation, adjust 'D' to refer to template.
218const Decl *adjustDeclToTemplate(const Decl *D) {
219  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
220    // Is this function declaration part of a function template?
221    if (const FunctionTemplateDecl *FTD = FD->getDescribedFunctionTemplate())
222      return FTD;
223
224    // Nothing to do if function is not an implicit instantiation.
225    if (FD->getTemplateSpecializationKind() != TSK_ImplicitInstantiation)
226      return D;
227
228    // Function is an implicit instantiation of a function template?
229    if (const FunctionTemplateDecl *FTD = FD->getPrimaryTemplate())
230      return FTD;
231
232    // Function is instantiated from a member definition of a class template?
233    if (const FunctionDecl *MemberDecl =
234            FD->getInstantiatedFromMemberFunction())
235      return MemberDecl;
236
237    return D;
238  }
239  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
240    // Static data member is instantiated from a member definition of a class
241    // template?
242    if (VD->isStaticDataMember())
243      if (const VarDecl *MemberDecl = VD->getInstantiatedFromStaticDataMember())
244        return MemberDecl;
245
246    return D;
247  }
248  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(D)) {
249    // Is this class declaration part of a class template?
250    if (const ClassTemplateDecl *CTD = CRD->getDescribedClassTemplate())
251      return CTD;
252
253    // Class is an implicit instantiation of a class template or partial
254    // specialization?
255    if (const ClassTemplateSpecializationDecl *CTSD =
256            dyn_cast<ClassTemplateSpecializationDecl>(CRD)) {
257      if (CTSD->getSpecializationKind() != TSK_ImplicitInstantiation)
258        return D;
259      llvm::PointerUnion<ClassTemplateDecl *,
260                         ClassTemplatePartialSpecializationDecl *>
261          PU = CTSD->getSpecializedTemplateOrPartial();
262      return PU.is<ClassTemplateDecl*>() ?
263          static_cast<const Decl*>(PU.get<ClassTemplateDecl *>()) :
264          static_cast<const Decl*>(
265              PU.get<ClassTemplatePartialSpecializationDecl *>());
266    }
267
268    // Class is instantiated from a member definition of a class template?
269    if (const MemberSpecializationInfo *Info =
270                   CRD->getMemberSpecializationInfo())
271      return Info->getInstantiatedFrom();
272
273    return D;
274  }
275  if (const EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
276    // Enum is instantiated from a member definition of a class template?
277    if (const EnumDecl *MemberDecl = ED->getInstantiatedFromMemberEnum())
278      return MemberDecl;
279
280    return D;
281  }
282  // FIXME: Adjust alias templates?
283  return D;
284}
285} // unnamed namespace
286
287const RawComment *ASTContext::getRawCommentForAnyRedecl(
288                                                const Decl *D,
289                                                const Decl **OriginalDecl) const {
290  D = adjustDeclToTemplate(D);
291
292  // Check whether we have cached a comment for this declaration already.
293  {
294    llvm::DenseMap<const Decl *, RawCommentAndCacheFlags>::iterator Pos =
295        RedeclComments.find(D);
296    if (Pos != RedeclComments.end()) {
297      const RawCommentAndCacheFlags &Raw = Pos->second;
298      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
299        if (OriginalDecl)
300          *OriginalDecl = Raw.getOriginalDecl();
301        return Raw.getRaw();
302      }
303    }
304  }
305
306  // Search for comments attached to declarations in the redeclaration chain.
307  const RawComment *RC = NULL;
308  const Decl *OriginalDeclForRC = NULL;
309  for (Decl::redecl_iterator I = D->redecls_begin(),
310                             E = D->redecls_end();
311       I != E; ++I) {
312    llvm::DenseMap<const Decl *, RawCommentAndCacheFlags>::iterator Pos =
313        RedeclComments.find(*I);
314    if (Pos != RedeclComments.end()) {
315      const RawCommentAndCacheFlags &Raw = Pos->second;
316      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
317        RC = Raw.getRaw();
318        OriginalDeclForRC = Raw.getOriginalDecl();
319        break;
320      }
321    } else {
322      RC = getRawCommentForDeclNoCache(*I);
323      OriginalDeclForRC = *I;
324      RawCommentAndCacheFlags Raw;
325      if (RC) {
326        Raw.setRaw(RC);
327        Raw.setKind(RawCommentAndCacheFlags::FromDecl);
328      } else
329        Raw.setKind(RawCommentAndCacheFlags::NoCommentInDecl);
330      Raw.setOriginalDecl(*I);
331      RedeclComments[*I] = Raw;
332      if (RC)
333        break;
334    }
335  }
336
337  // If we found a comment, it should be a documentation comment.
338  assert(!RC || RC->isDocumentation());
339
340  if (OriginalDecl)
341    *OriginalDecl = OriginalDeclForRC;
342
343  // Update cache for every declaration in the redeclaration chain.
344  RawCommentAndCacheFlags Raw;
345  Raw.setRaw(RC);
346  Raw.setKind(RawCommentAndCacheFlags::FromRedecl);
347  Raw.setOriginalDecl(OriginalDeclForRC);
348
349  for (Decl::redecl_iterator I = D->redecls_begin(),
350                             E = D->redecls_end();
351       I != E; ++I) {
352    RawCommentAndCacheFlags &R = RedeclComments[*I];
353    if (R.getKind() == RawCommentAndCacheFlags::NoCommentInDecl)
354      R = Raw;
355  }
356
357  return RC;
358}
359
360static void addRedeclaredMethods(const ObjCMethodDecl *ObjCMethod,
361                   SmallVectorImpl<const NamedDecl *> &Redeclared) {
362  const DeclContext *DC = ObjCMethod->getDeclContext();
363  if (const ObjCImplDecl *IMD = dyn_cast<ObjCImplDecl>(DC)) {
364    const ObjCInterfaceDecl *ID = IMD->getClassInterface();
365    if (!ID)
366      return;
367    // Add redeclared method here.
368    for (const ObjCCategoryDecl *ClsExtDecl = ID->getFirstClassExtension();
369         ClsExtDecl; ClsExtDecl = ClsExtDecl->getNextClassExtension()) {
370      if (ObjCMethodDecl *RedeclaredMethod =
371            ClsExtDecl->getMethod(ObjCMethod->getSelector(),
372                                  ObjCMethod->isInstanceMethod()))
373        Redeclared.push_back(RedeclaredMethod);
374    }
375  }
376}
377
378comments::FullComment *ASTContext::cloneFullComment(comments::FullComment *FC,
379                                                    const Decl *D) const {
380  comments::DeclInfo *ThisDeclInfo = new (*this) comments::DeclInfo;
381  ThisDeclInfo->CommentDecl = D;
382  ThisDeclInfo->IsFilled = false;
383  ThisDeclInfo->fill();
384  ThisDeclInfo->CommentDecl = FC->getDecl();
385  comments::FullComment *CFC =
386    new (*this) comments::FullComment(FC->getBlocks(),
387                                      ThisDeclInfo);
388  return CFC;
389
390}
391
392comments::FullComment *ASTContext::getCommentForDecl(
393                                              const Decl *D,
394                                              const Preprocessor *PP) const {
395  D = adjustDeclToTemplate(D);
396
397  const Decl *Canonical = D->getCanonicalDecl();
398  llvm::DenseMap<const Decl *, comments::FullComment *>::iterator Pos =
399      ParsedComments.find(Canonical);
400
401  if (Pos != ParsedComments.end()) {
402    if (Canonical != D) {
403      comments::FullComment *FC = Pos->second;
404      comments::FullComment *CFC = cloneFullComment(FC, D);
405      return CFC;
406    }
407    return Pos->second;
408  }
409
410  const Decl *OriginalDecl;
411
412  const RawComment *RC = getRawCommentForAnyRedecl(D, &OriginalDecl);
413  if (!RC) {
414    if (isa<ObjCMethodDecl>(D) || isa<FunctionDecl>(D)) {
415      SmallVector<const NamedDecl*, 8> Overridden;
416      if (const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D))
417        addRedeclaredMethods(OMD, Overridden);
418      getOverriddenMethods(dyn_cast<NamedDecl>(D), Overridden);
419      for (unsigned i = 0, e = Overridden.size(); i < e; i++) {
420        if (comments::FullComment *FC = getCommentForDecl(Overridden[i], PP)) {
421          comments::FullComment *CFC = cloneFullComment(FC, D);
422          return CFC;
423        }
424      }
425    }
426    return NULL;
427  }
428
429  // If the RawComment was attached to other redeclaration of this Decl, we
430  // should parse the comment in context of that other Decl.  This is important
431  // because comments can contain references to parameter names which can be
432  // different across redeclarations.
433  if (D != OriginalDecl)
434    return getCommentForDecl(OriginalDecl, PP);
435
436  comments::FullComment *FC = RC->parse(*this, PP, D);
437  ParsedComments[Canonical] = FC;
438  return FC;
439}
440
441void
442ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
443                                               TemplateTemplateParmDecl *Parm) {
444  ID.AddInteger(Parm->getDepth());
445  ID.AddInteger(Parm->getPosition());
446  ID.AddBoolean(Parm->isParameterPack());
447
448  TemplateParameterList *Params = Parm->getTemplateParameters();
449  ID.AddInteger(Params->size());
450  for (TemplateParameterList::const_iterator P = Params->begin(),
451                                          PEnd = Params->end();
452       P != PEnd; ++P) {
453    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
454      ID.AddInteger(0);
455      ID.AddBoolean(TTP->isParameterPack());
456      continue;
457    }
458
459    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
460      ID.AddInteger(1);
461      ID.AddBoolean(NTTP->isParameterPack());
462      ID.AddPointer(NTTP->getType().getCanonicalType().getAsOpaquePtr());
463      if (NTTP->isExpandedParameterPack()) {
464        ID.AddBoolean(true);
465        ID.AddInteger(NTTP->getNumExpansionTypes());
466        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
467          QualType T = NTTP->getExpansionType(I);
468          ID.AddPointer(T.getCanonicalType().getAsOpaquePtr());
469        }
470      } else
471        ID.AddBoolean(false);
472      continue;
473    }
474
475    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
476    ID.AddInteger(2);
477    Profile(ID, TTP);
478  }
479}
480
481TemplateTemplateParmDecl *
482ASTContext::getCanonicalTemplateTemplateParmDecl(
483                                          TemplateTemplateParmDecl *TTP) const {
484  // Check if we already have a canonical template template parameter.
485  llvm::FoldingSetNodeID ID;
486  CanonicalTemplateTemplateParm::Profile(ID, TTP);
487  void *InsertPos = 0;
488  CanonicalTemplateTemplateParm *Canonical
489    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
490  if (Canonical)
491    return Canonical->getParam();
492
493  // Build a canonical template parameter list.
494  TemplateParameterList *Params = TTP->getTemplateParameters();
495  SmallVector<NamedDecl *, 4> CanonParams;
496  CanonParams.reserve(Params->size());
497  for (TemplateParameterList::const_iterator P = Params->begin(),
498                                          PEnd = Params->end();
499       P != PEnd; ++P) {
500    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
501      CanonParams.push_back(
502                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
503                                               SourceLocation(),
504                                               SourceLocation(),
505                                               TTP->getDepth(),
506                                               TTP->getIndex(), 0, false,
507                                               TTP->isParameterPack()));
508    else if (NonTypeTemplateParmDecl *NTTP
509             = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
510      QualType T = getCanonicalType(NTTP->getType());
511      TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
512      NonTypeTemplateParmDecl *Param;
513      if (NTTP->isExpandedParameterPack()) {
514        SmallVector<QualType, 2> ExpandedTypes;
515        SmallVector<TypeSourceInfo *, 2> ExpandedTInfos;
516        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
517          ExpandedTypes.push_back(getCanonicalType(NTTP->getExpansionType(I)));
518          ExpandedTInfos.push_back(
519                                getTrivialTypeSourceInfo(ExpandedTypes.back()));
520        }
521
522        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
523                                                SourceLocation(),
524                                                SourceLocation(),
525                                                NTTP->getDepth(),
526                                                NTTP->getPosition(), 0,
527                                                T,
528                                                TInfo,
529                                                ExpandedTypes.data(),
530                                                ExpandedTypes.size(),
531                                                ExpandedTInfos.data());
532      } else {
533        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
534                                                SourceLocation(),
535                                                SourceLocation(),
536                                                NTTP->getDepth(),
537                                                NTTP->getPosition(), 0,
538                                                T,
539                                                NTTP->isParameterPack(),
540                                                TInfo);
541      }
542      CanonParams.push_back(Param);
543
544    } else
545      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
546                                           cast<TemplateTemplateParmDecl>(*P)));
547  }
548
549  TemplateTemplateParmDecl *CanonTTP
550    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
551                                       SourceLocation(), TTP->getDepth(),
552                                       TTP->getPosition(),
553                                       TTP->isParameterPack(),
554                                       0,
555                         TemplateParameterList::Create(*this, SourceLocation(),
556                                                       SourceLocation(),
557                                                       CanonParams.data(),
558                                                       CanonParams.size(),
559                                                       SourceLocation()));
560
561  // Get the new insert position for the node we care about.
562  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
563  assert(Canonical == 0 && "Shouldn't be in the map!");
564  (void)Canonical;
565
566  // Create the canonical template template parameter entry.
567  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
568  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
569  return CanonTTP;
570}
571
572CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
573  if (!LangOpts.CPlusPlus) return 0;
574
575  switch (T.getCXXABI()) {
576  case CXXABI_ARM:
577    return CreateARMCXXABI(*this);
578  case CXXABI_Itanium:
579    return CreateItaniumCXXABI(*this);
580  case CXXABI_Microsoft:
581    return CreateMicrosoftCXXABI(*this);
582  }
583  llvm_unreachable("Invalid CXXABI type!");
584}
585
586static const LangAS::Map *getAddressSpaceMap(const TargetInfo &T,
587                                             const LangOptions &LOpts) {
588  if (LOpts.FakeAddressSpaceMap) {
589    // The fake address space map must have a distinct entry for each
590    // language-specific address space.
591    static const unsigned FakeAddrSpaceMap[] = {
592      1, // opencl_global
593      2, // opencl_local
594      3, // opencl_constant
595      4, // cuda_device
596      5, // cuda_constant
597      6  // cuda_shared
598    };
599    return &FakeAddrSpaceMap;
600  } else {
601    return &T.getAddressSpaceMap();
602  }
603}
604
605ASTContext::ASTContext(LangOptions& LOpts, SourceManager &SM,
606                       const TargetInfo *t,
607                       IdentifierTable &idents, SelectorTable &sels,
608                       Builtin::Context &builtins,
609                       unsigned size_reserve,
610                       bool DelayInitialization)
611  : FunctionProtoTypes(this_()),
612    TemplateSpecializationTypes(this_()),
613    DependentTemplateSpecializationTypes(this_()),
614    SubstTemplateTemplateParmPacks(this_()),
615    GlobalNestedNameSpecifier(0),
616    Int128Decl(0), UInt128Decl(0),
617    BuiltinVaListDecl(0),
618    ObjCIdDecl(0), ObjCSelDecl(0), ObjCClassDecl(0), ObjCProtocolClassDecl(0),
619    BOOLDecl(0),
620    CFConstantStringTypeDecl(0), ObjCInstanceTypeDecl(0),
621    FILEDecl(0),
622    jmp_bufDecl(0), sigjmp_bufDecl(0), ucontext_tDecl(0),
623    BlockDescriptorType(0), BlockDescriptorExtendedType(0),
624    cudaConfigureCallDecl(0),
625    NullTypeSourceInfo(QualType()),
626    FirstLocalImport(), LastLocalImport(),
627    SourceMgr(SM), LangOpts(LOpts),
628    AddrSpaceMap(0), Target(t), PrintingPolicy(LOpts),
629    Idents(idents), Selectors(sels),
630    BuiltinInfo(builtins),
631    DeclarationNames(*this),
632    ExternalSource(0), Listener(0),
633    Comments(SM), CommentsLoaded(false),
634    CommentCommandTraits(BumpAlloc),
635    LastSDM(0, 0),
636    UniqueBlockByRefTypeID(0)
637{
638  if (size_reserve > 0) Types.reserve(size_reserve);
639  TUDecl = TranslationUnitDecl::Create(*this);
640
641  if (!DelayInitialization) {
642    assert(t && "No target supplied for ASTContext initialization");
643    InitBuiltinTypes(*t);
644  }
645}
646
647ASTContext::~ASTContext() {
648  // Release the DenseMaps associated with DeclContext objects.
649  // FIXME: Is this the ideal solution?
650  ReleaseDeclContextMaps();
651
652  // Call all of the deallocation functions.
653  for (unsigned I = 0, N = Deallocations.size(); I != N; ++I)
654    Deallocations[I].first(Deallocations[I].second);
655
656  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
657  // because they can contain DenseMaps.
658  for (llvm::DenseMap<const ObjCContainerDecl*,
659       const ASTRecordLayout*>::iterator
660       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
661    // Increment in loop to prevent using deallocated memory.
662    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
663      R->Destroy(*this);
664
665  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
666       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
667    // Increment in loop to prevent using deallocated memory.
668    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
669      R->Destroy(*this);
670  }
671
672  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
673                                                    AEnd = DeclAttrs.end();
674       A != AEnd; ++A)
675    A->second->~AttrVec();
676}
677
678void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
679  Deallocations.push_back(std::make_pair(Callback, Data));
680}
681
682void
683ASTContext::setExternalSource(OwningPtr<ExternalASTSource> &Source) {
684  ExternalSource.reset(Source.take());
685}
686
687void ASTContext::PrintStats() const {
688  llvm::errs() << "\n*** AST Context Stats:\n";
689  llvm::errs() << "  " << Types.size() << " types total.\n";
690
691  unsigned counts[] = {
692#define TYPE(Name, Parent) 0,
693#define ABSTRACT_TYPE(Name, Parent)
694#include "clang/AST/TypeNodes.def"
695    0 // Extra
696  };
697
698  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
699    Type *T = Types[i];
700    counts[(unsigned)T->getTypeClass()]++;
701  }
702
703  unsigned Idx = 0;
704  unsigned TotalBytes = 0;
705#define TYPE(Name, Parent)                                              \
706  if (counts[Idx])                                                      \
707    llvm::errs() << "    " << counts[Idx] << " " << #Name               \
708                 << " types\n";                                         \
709  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
710  ++Idx;
711#define ABSTRACT_TYPE(Name, Parent)
712#include "clang/AST/TypeNodes.def"
713
714  llvm::errs() << "Total bytes = " << TotalBytes << "\n";
715
716  // Implicit special member functions.
717  llvm::errs() << NumImplicitDefaultConstructorsDeclared << "/"
718               << NumImplicitDefaultConstructors
719               << " implicit default constructors created\n";
720  llvm::errs() << NumImplicitCopyConstructorsDeclared << "/"
721               << NumImplicitCopyConstructors
722               << " implicit copy constructors created\n";
723  if (getLangOpts().CPlusPlus)
724    llvm::errs() << NumImplicitMoveConstructorsDeclared << "/"
725                 << NumImplicitMoveConstructors
726                 << " implicit move constructors created\n";
727  llvm::errs() << NumImplicitCopyAssignmentOperatorsDeclared << "/"
728               << NumImplicitCopyAssignmentOperators
729               << " implicit copy assignment operators created\n";
730  if (getLangOpts().CPlusPlus)
731    llvm::errs() << NumImplicitMoveAssignmentOperatorsDeclared << "/"
732                 << NumImplicitMoveAssignmentOperators
733                 << " implicit move assignment operators created\n";
734  llvm::errs() << NumImplicitDestructorsDeclared << "/"
735               << NumImplicitDestructors
736               << " implicit destructors created\n";
737
738  if (ExternalSource.get()) {
739    llvm::errs() << "\n";
740    ExternalSource->PrintStats();
741  }
742
743  BumpAlloc.PrintStats();
744}
745
746TypedefDecl *ASTContext::getInt128Decl() const {
747  if (!Int128Decl) {
748    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(Int128Ty);
749    Int128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
750                                     getTranslationUnitDecl(),
751                                     SourceLocation(),
752                                     SourceLocation(),
753                                     &Idents.get("__int128_t"),
754                                     TInfo);
755  }
756
757  return Int128Decl;
758}
759
760TypedefDecl *ASTContext::getUInt128Decl() const {
761  if (!UInt128Decl) {
762    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(UnsignedInt128Ty);
763    UInt128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
764                                     getTranslationUnitDecl(),
765                                     SourceLocation(),
766                                     SourceLocation(),
767                                     &Idents.get("__uint128_t"),
768                                     TInfo);
769  }
770
771  return UInt128Decl;
772}
773
774void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
775  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
776  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
777  Types.push_back(Ty);
778}
779
780void ASTContext::InitBuiltinTypes(const TargetInfo &Target) {
781  assert((!this->Target || this->Target == &Target) &&
782         "Incorrect target reinitialization");
783  assert(VoidTy.isNull() && "Context reinitialized?");
784
785  this->Target = &Target;
786
787  ABI.reset(createCXXABI(Target));
788  AddrSpaceMap = getAddressSpaceMap(Target, LangOpts);
789
790  // C99 6.2.5p19.
791  InitBuiltinType(VoidTy,              BuiltinType::Void);
792
793  // C99 6.2.5p2.
794  InitBuiltinType(BoolTy,              BuiltinType::Bool);
795  // C99 6.2.5p3.
796  if (LangOpts.CharIsSigned)
797    InitBuiltinType(CharTy,            BuiltinType::Char_S);
798  else
799    InitBuiltinType(CharTy,            BuiltinType::Char_U);
800  // C99 6.2.5p4.
801  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
802  InitBuiltinType(ShortTy,             BuiltinType::Short);
803  InitBuiltinType(IntTy,               BuiltinType::Int);
804  InitBuiltinType(LongTy,              BuiltinType::Long);
805  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
806
807  // C99 6.2.5p6.
808  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
809  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
810  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
811  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
812  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
813
814  // C99 6.2.5p10.
815  InitBuiltinType(FloatTy,             BuiltinType::Float);
816  InitBuiltinType(DoubleTy,            BuiltinType::Double);
817  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
818
819  // GNU extension, 128-bit integers.
820  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
821  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
822
823  if (LangOpts.CPlusPlus && LangOpts.WChar) { // C++ 3.9.1p5
824    if (TargetInfo::isTypeSigned(Target.getWCharType()))
825      InitBuiltinType(WCharTy,           BuiltinType::WChar_S);
826    else  // -fshort-wchar makes wchar_t be unsigned.
827      InitBuiltinType(WCharTy,           BuiltinType::WChar_U);
828  } else // C99 (or C++ using -fno-wchar)
829    WCharTy = getFromTargetType(Target.getWCharType());
830
831  WIntTy = getFromTargetType(Target.getWIntType());
832
833  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
834    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
835  else // C99
836    Char16Ty = getFromTargetType(Target.getChar16Type());
837
838  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
839    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
840  else // C99
841    Char32Ty = getFromTargetType(Target.getChar32Type());
842
843  // Placeholder type for type-dependent expressions whose type is
844  // completely unknown. No code should ever check a type against
845  // DependentTy and users should never see it; however, it is here to
846  // help diagnose failures to properly check for type-dependent
847  // expressions.
848  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
849
850  // Placeholder type for functions.
851  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
852
853  // Placeholder type for bound members.
854  InitBuiltinType(BoundMemberTy,       BuiltinType::BoundMember);
855
856  // Placeholder type for pseudo-objects.
857  InitBuiltinType(PseudoObjectTy,      BuiltinType::PseudoObject);
858
859  // "any" type; useful for debugger-like clients.
860  InitBuiltinType(UnknownAnyTy,        BuiltinType::UnknownAny);
861
862  // Placeholder type for unbridged ARC casts.
863  InitBuiltinType(ARCUnbridgedCastTy,  BuiltinType::ARCUnbridgedCast);
864
865  // Placeholder type for builtin functions.
866  InitBuiltinType(BuiltinFnTy,  BuiltinType::BuiltinFn);
867
868  // C99 6.2.5p11.
869  FloatComplexTy      = getComplexType(FloatTy);
870  DoubleComplexTy     = getComplexType(DoubleTy);
871  LongDoubleComplexTy = getComplexType(LongDoubleTy);
872
873  // Builtin types for 'id', 'Class', and 'SEL'.
874  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
875  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
876  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
877
878  if (LangOpts.OpenCL) {
879    InitBuiltinType(OCLImage1dTy, BuiltinType::OCLImage1d);
880    InitBuiltinType(OCLImage1dArrayTy, BuiltinType::OCLImage1dArray);
881    InitBuiltinType(OCLImage1dBufferTy, BuiltinType::OCLImage1dBuffer);
882    InitBuiltinType(OCLImage2dTy, BuiltinType::OCLImage2d);
883    InitBuiltinType(OCLImage2dArrayTy, BuiltinType::OCLImage2dArray);
884    InitBuiltinType(OCLImage3dTy, BuiltinType::OCLImage3d);
885  }
886
887  // Builtin type for __objc_yes and __objc_no
888  ObjCBuiltinBoolTy = (Target.useSignedCharForObjCBool() ?
889                       SignedCharTy : BoolTy);
890
891  ObjCConstantStringType = QualType();
892
893  ObjCSuperType = QualType();
894
895  // void * type
896  VoidPtrTy = getPointerType(VoidTy);
897
898  // nullptr type (C++0x 2.14.7)
899  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
900
901  // half type (OpenCL 6.1.1.1) / ARM NEON __fp16
902  InitBuiltinType(HalfTy, BuiltinType::Half);
903
904  // Builtin type used to help define __builtin_va_list.
905  VaListTagTy = QualType();
906}
907
908DiagnosticsEngine &ASTContext::getDiagnostics() const {
909  return SourceMgr.getDiagnostics();
910}
911
912AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
913  AttrVec *&Result = DeclAttrs[D];
914  if (!Result) {
915    void *Mem = Allocate(sizeof(AttrVec));
916    Result = new (Mem) AttrVec;
917  }
918
919  return *Result;
920}
921
922/// \brief Erase the attributes corresponding to the given declaration.
923void ASTContext::eraseDeclAttrs(const Decl *D) {
924  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
925  if (Pos != DeclAttrs.end()) {
926    Pos->second->~AttrVec();
927    DeclAttrs.erase(Pos);
928  }
929}
930
931MemberSpecializationInfo *
932ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
933  assert(Var->isStaticDataMember() && "Not a static data member");
934  llvm::DenseMap<const VarDecl *, MemberSpecializationInfo *>::iterator Pos
935    = InstantiatedFromStaticDataMember.find(Var);
936  if (Pos == InstantiatedFromStaticDataMember.end())
937    return 0;
938
939  return Pos->second;
940}
941
942void
943ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
944                                                TemplateSpecializationKind TSK,
945                                          SourceLocation PointOfInstantiation) {
946  assert(Inst->isStaticDataMember() && "Not a static data member");
947  assert(Tmpl->isStaticDataMember() && "Not a static data member");
948  assert(!InstantiatedFromStaticDataMember[Inst] &&
949         "Already noted what static data member was instantiated from");
950  InstantiatedFromStaticDataMember[Inst]
951    = new (*this) MemberSpecializationInfo(Tmpl, TSK, PointOfInstantiation);
952}
953
954FunctionDecl *ASTContext::getClassScopeSpecializationPattern(
955                                                     const FunctionDecl *FD){
956  assert(FD && "Specialization is 0");
957  llvm::DenseMap<const FunctionDecl*, FunctionDecl *>::const_iterator Pos
958    = ClassScopeSpecializationPattern.find(FD);
959  if (Pos == ClassScopeSpecializationPattern.end())
960    return 0;
961
962  return Pos->second;
963}
964
965void ASTContext::setClassScopeSpecializationPattern(FunctionDecl *FD,
966                                        FunctionDecl *Pattern) {
967  assert(FD && "Specialization is 0");
968  assert(Pattern && "Class scope specialization pattern is 0");
969  ClassScopeSpecializationPattern[FD] = Pattern;
970}
971
972NamedDecl *
973ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
974  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
975    = InstantiatedFromUsingDecl.find(UUD);
976  if (Pos == InstantiatedFromUsingDecl.end())
977    return 0;
978
979  return Pos->second;
980}
981
982void
983ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
984  assert((isa<UsingDecl>(Pattern) ||
985          isa<UnresolvedUsingValueDecl>(Pattern) ||
986          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
987         "pattern decl is not a using decl");
988  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
989  InstantiatedFromUsingDecl[Inst] = Pattern;
990}
991
992UsingShadowDecl *
993ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
994  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
995    = InstantiatedFromUsingShadowDecl.find(Inst);
996  if (Pos == InstantiatedFromUsingShadowDecl.end())
997    return 0;
998
999  return Pos->second;
1000}
1001
1002void
1003ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
1004                                               UsingShadowDecl *Pattern) {
1005  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
1006  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
1007}
1008
1009FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
1010  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
1011    = InstantiatedFromUnnamedFieldDecl.find(Field);
1012  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
1013    return 0;
1014
1015  return Pos->second;
1016}
1017
1018void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
1019                                                     FieldDecl *Tmpl) {
1020  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
1021  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
1022  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
1023         "Already noted what unnamed field was instantiated from");
1024
1025  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
1026}
1027
1028bool ASTContext::ZeroBitfieldFollowsNonBitfield(const FieldDecl *FD,
1029                                    const FieldDecl *LastFD) const {
1030  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
1031          FD->getBitWidthValue(*this) == 0);
1032}
1033
1034bool ASTContext::ZeroBitfieldFollowsBitfield(const FieldDecl *FD,
1035                                             const FieldDecl *LastFD) const {
1036  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
1037          FD->getBitWidthValue(*this) == 0 &&
1038          LastFD->getBitWidthValue(*this) != 0);
1039}
1040
1041bool ASTContext::BitfieldFollowsBitfield(const FieldDecl *FD,
1042                                         const FieldDecl *LastFD) const {
1043  return (FD->isBitField() && LastFD && LastFD->isBitField() &&
1044          FD->getBitWidthValue(*this) &&
1045          LastFD->getBitWidthValue(*this));
1046}
1047
1048bool ASTContext::NonBitfieldFollowsBitfield(const FieldDecl *FD,
1049                                         const FieldDecl *LastFD) const {
1050  return (!FD->isBitField() && LastFD && LastFD->isBitField() &&
1051          LastFD->getBitWidthValue(*this));
1052}
1053
1054bool ASTContext::BitfieldFollowsNonBitfield(const FieldDecl *FD,
1055                                             const FieldDecl *LastFD) const {
1056  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
1057          FD->getBitWidthValue(*this));
1058}
1059
1060ASTContext::overridden_cxx_method_iterator
1061ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
1062  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1063    = OverriddenMethods.find(Method->getCanonicalDecl());
1064  if (Pos == OverriddenMethods.end())
1065    return 0;
1066
1067  return Pos->second.begin();
1068}
1069
1070ASTContext::overridden_cxx_method_iterator
1071ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
1072  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1073    = OverriddenMethods.find(Method->getCanonicalDecl());
1074  if (Pos == OverriddenMethods.end())
1075    return 0;
1076
1077  return Pos->second.end();
1078}
1079
1080unsigned
1081ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
1082  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1083    = OverriddenMethods.find(Method->getCanonicalDecl());
1084  if (Pos == OverriddenMethods.end())
1085    return 0;
1086
1087  return Pos->second.size();
1088}
1089
1090void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
1091                                     const CXXMethodDecl *Overridden) {
1092  assert(Method->isCanonicalDecl() && Overridden->isCanonicalDecl());
1093  OverriddenMethods[Method].push_back(Overridden);
1094}
1095
1096void ASTContext::getOverriddenMethods(
1097                      const NamedDecl *D,
1098                      SmallVectorImpl<const NamedDecl *> &Overridden) const {
1099  assert(D);
1100
1101  if (const CXXMethodDecl *CXXMethod = dyn_cast<CXXMethodDecl>(D)) {
1102    Overridden.append(CXXMethod->begin_overridden_methods(),
1103                      CXXMethod->end_overridden_methods());
1104    return;
1105  }
1106
1107  const ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(D);
1108  if (!Method)
1109    return;
1110
1111  SmallVector<const ObjCMethodDecl *, 8> OverDecls;
1112  Method->getOverriddenMethods(OverDecls);
1113  Overridden.append(OverDecls.begin(), OverDecls.end());
1114}
1115
1116void ASTContext::addedLocalImportDecl(ImportDecl *Import) {
1117  assert(!Import->NextLocalImport && "Import declaration already in the chain");
1118  assert(!Import->isFromASTFile() && "Non-local import declaration");
1119  if (!FirstLocalImport) {
1120    FirstLocalImport = Import;
1121    LastLocalImport = Import;
1122    return;
1123  }
1124
1125  LastLocalImport->NextLocalImport = Import;
1126  LastLocalImport = Import;
1127}
1128
1129//===----------------------------------------------------------------------===//
1130//                         Type Sizing and Analysis
1131//===----------------------------------------------------------------------===//
1132
1133/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
1134/// scalar floating point type.
1135const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
1136  const BuiltinType *BT = T->getAs<BuiltinType>();
1137  assert(BT && "Not a floating point type!");
1138  switch (BT->getKind()) {
1139  default: llvm_unreachable("Not a floating point type!");
1140  case BuiltinType::Half:       return Target->getHalfFormat();
1141  case BuiltinType::Float:      return Target->getFloatFormat();
1142  case BuiltinType::Double:     return Target->getDoubleFormat();
1143  case BuiltinType::LongDouble: return Target->getLongDoubleFormat();
1144  }
1145}
1146
1147/// getDeclAlign - Return a conservative estimate of the alignment of the
1148/// specified decl.  Note that bitfields do not have a valid alignment, so
1149/// this method will assert on them.
1150/// If @p RefAsPointee, references are treated like their underlying type
1151/// (for alignof), else they're treated like pointers (for CodeGen).
1152CharUnits ASTContext::getDeclAlign(const Decl *D, bool RefAsPointee) const {
1153  unsigned Align = Target->getCharWidth();
1154
1155  bool UseAlignAttrOnly = false;
1156  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
1157    Align = AlignFromAttr;
1158
1159    // __attribute__((aligned)) can increase or decrease alignment
1160    // *except* on a struct or struct member, where it only increases
1161    // alignment unless 'packed' is also specified.
1162    //
1163    // It is an error for alignas to decrease alignment, so we can
1164    // ignore that possibility;  Sema should diagnose it.
1165    if (isa<FieldDecl>(D)) {
1166      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
1167        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1168    } else {
1169      UseAlignAttrOnly = true;
1170    }
1171  }
1172  else if (isa<FieldDecl>(D))
1173      UseAlignAttrOnly =
1174        D->hasAttr<PackedAttr>() ||
1175        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1176
1177  // If we're using the align attribute only, just ignore everything
1178  // else about the declaration and its type.
1179  if (UseAlignAttrOnly) {
1180    // do nothing
1181
1182  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
1183    QualType T = VD->getType();
1184    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
1185      if (RefAsPointee)
1186        T = RT->getPointeeType();
1187      else
1188        T = getPointerType(RT->getPointeeType());
1189    }
1190    if (!T->isIncompleteType() && !T->isFunctionType()) {
1191      // Adjust alignments of declarations with array type by the
1192      // large-array alignment on the target.
1193      unsigned MinWidth = Target->getLargeArrayMinWidth();
1194      const ArrayType *arrayType;
1195      if (MinWidth && (arrayType = getAsArrayType(T))) {
1196        if (isa<VariableArrayType>(arrayType))
1197          Align = std::max(Align, Target->getLargeArrayAlign());
1198        else if (isa<ConstantArrayType>(arrayType) &&
1199                 MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
1200          Align = std::max(Align, Target->getLargeArrayAlign());
1201
1202        // Walk through any array types while we're at it.
1203        T = getBaseElementType(arrayType);
1204      }
1205      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
1206    }
1207
1208    // Fields can be subject to extra alignment constraints, like if
1209    // the field is packed, the struct is packed, or the struct has a
1210    // a max-field-alignment constraint (#pragma pack).  So calculate
1211    // the actual alignment of the field within the struct, and then
1212    // (as we're expected to) constrain that by the alignment of the type.
1213    if (const FieldDecl *field = dyn_cast<FieldDecl>(VD)) {
1214      // So calculate the alignment of the field.
1215      const ASTRecordLayout &layout = getASTRecordLayout(field->getParent());
1216
1217      // Start with the record's overall alignment.
1218      unsigned fieldAlign = toBits(layout.getAlignment());
1219
1220      // Use the GCD of that and the offset within the record.
1221      uint64_t offset = layout.getFieldOffset(field->getFieldIndex());
1222      if (offset > 0) {
1223        // Alignment is always a power of 2, so the GCD will be a power of 2,
1224        // which means we get to do this crazy thing instead of Euclid's.
1225        uint64_t lowBitOfOffset = offset & (~offset + 1);
1226        if (lowBitOfOffset < fieldAlign)
1227          fieldAlign = static_cast<unsigned>(lowBitOfOffset);
1228      }
1229
1230      Align = std::min(Align, fieldAlign);
1231    }
1232  }
1233
1234  return toCharUnitsFromBits(Align);
1235}
1236
1237// getTypeInfoDataSizeInChars - Return the size of a type, in
1238// chars. If the type is a record, its data size is returned.  This is
1239// the size of the memcpy that's performed when assigning this type
1240// using a trivial copy/move assignment operator.
1241std::pair<CharUnits, CharUnits>
1242ASTContext::getTypeInfoDataSizeInChars(QualType T) const {
1243  std::pair<CharUnits, CharUnits> sizeAndAlign = getTypeInfoInChars(T);
1244
1245  // In C++, objects can sometimes be allocated into the tail padding
1246  // of a base-class subobject.  We decide whether that's possible
1247  // during class layout, so here we can just trust the layout results.
1248  if (getLangOpts().CPlusPlus) {
1249    if (const RecordType *RT = T->getAs<RecordType>()) {
1250      const ASTRecordLayout &layout = getASTRecordLayout(RT->getDecl());
1251      sizeAndAlign.first = layout.getDataSize();
1252    }
1253  }
1254
1255  return sizeAndAlign;
1256}
1257
1258std::pair<CharUnits, CharUnits>
1259ASTContext::getTypeInfoInChars(const Type *T) const {
1260  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
1261  return std::make_pair(toCharUnitsFromBits(Info.first),
1262                        toCharUnitsFromBits(Info.second));
1263}
1264
1265std::pair<CharUnits, CharUnits>
1266ASTContext::getTypeInfoInChars(QualType T) const {
1267  return getTypeInfoInChars(T.getTypePtr());
1268}
1269
1270std::pair<uint64_t, unsigned> ASTContext::getTypeInfo(const Type *T) const {
1271  TypeInfoMap::iterator it = MemoizedTypeInfo.find(T);
1272  if (it != MemoizedTypeInfo.end())
1273    return it->second;
1274
1275  std::pair<uint64_t, unsigned> Info = getTypeInfoImpl(T);
1276  MemoizedTypeInfo.insert(std::make_pair(T, Info));
1277  return Info;
1278}
1279
1280/// getTypeInfoImpl - Return the size of the specified type, in bits.  This
1281/// method does not work on incomplete types.
1282///
1283/// FIXME: Pointers into different addr spaces could have different sizes and
1284/// alignment requirements: getPointerInfo should take an AddrSpace, this
1285/// should take a QualType, &c.
1286std::pair<uint64_t, unsigned>
1287ASTContext::getTypeInfoImpl(const Type *T) const {
1288  uint64_t Width=0;
1289  unsigned Align=8;
1290  switch (T->getTypeClass()) {
1291#define TYPE(Class, Base)
1292#define ABSTRACT_TYPE(Class, Base)
1293#define NON_CANONICAL_TYPE(Class, Base)
1294#define DEPENDENT_TYPE(Class, Base) case Type::Class:
1295#include "clang/AST/TypeNodes.def"
1296    llvm_unreachable("Should not see dependent types");
1297
1298  case Type::FunctionNoProto:
1299  case Type::FunctionProto:
1300    // GCC extension: alignof(function) = 32 bits
1301    Width = 0;
1302    Align = 32;
1303    break;
1304
1305  case Type::IncompleteArray:
1306  case Type::VariableArray:
1307    Width = 0;
1308    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
1309    break;
1310
1311  case Type::ConstantArray: {
1312    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
1313
1314    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
1315    uint64_t Size = CAT->getSize().getZExtValue();
1316    assert((Size == 0 || EltInfo.first <= (uint64_t)(-1)/Size) &&
1317           "Overflow in array type bit size evaluation");
1318    Width = EltInfo.first*Size;
1319    Align = EltInfo.second;
1320    Width = llvm::RoundUpToAlignment(Width, Align);
1321    break;
1322  }
1323  case Type::ExtVector:
1324  case Type::Vector: {
1325    const VectorType *VT = cast<VectorType>(T);
1326    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
1327    Width = EltInfo.first*VT->getNumElements();
1328    Align = Width;
1329    // If the alignment is not a power of 2, round up to the next power of 2.
1330    // This happens for non-power-of-2 length vectors.
1331    if (Align & (Align-1)) {
1332      Align = llvm::NextPowerOf2(Align);
1333      Width = llvm::RoundUpToAlignment(Width, Align);
1334    }
1335    // Adjust the alignment based on the target max.
1336    uint64_t TargetVectorAlign = Target->getMaxVectorAlign();
1337    if (TargetVectorAlign && TargetVectorAlign < Align)
1338      Align = TargetVectorAlign;
1339    break;
1340  }
1341
1342  case Type::Builtin:
1343    switch (cast<BuiltinType>(T)->getKind()) {
1344    default: llvm_unreachable("Unknown builtin type!");
1345    case BuiltinType::Void:
1346      // GCC extension: alignof(void) = 8 bits.
1347      Width = 0;
1348      Align = 8;
1349      break;
1350
1351    case BuiltinType::Bool:
1352      Width = Target->getBoolWidth();
1353      Align = Target->getBoolAlign();
1354      break;
1355    case BuiltinType::Char_S:
1356    case BuiltinType::Char_U:
1357    case BuiltinType::UChar:
1358    case BuiltinType::SChar:
1359      Width = Target->getCharWidth();
1360      Align = Target->getCharAlign();
1361      break;
1362    case BuiltinType::WChar_S:
1363    case BuiltinType::WChar_U:
1364      Width = Target->getWCharWidth();
1365      Align = Target->getWCharAlign();
1366      break;
1367    case BuiltinType::Char16:
1368      Width = Target->getChar16Width();
1369      Align = Target->getChar16Align();
1370      break;
1371    case BuiltinType::Char32:
1372      Width = Target->getChar32Width();
1373      Align = Target->getChar32Align();
1374      break;
1375    case BuiltinType::UShort:
1376    case BuiltinType::Short:
1377      Width = Target->getShortWidth();
1378      Align = Target->getShortAlign();
1379      break;
1380    case BuiltinType::UInt:
1381    case BuiltinType::Int:
1382      Width = Target->getIntWidth();
1383      Align = Target->getIntAlign();
1384      break;
1385    case BuiltinType::ULong:
1386    case BuiltinType::Long:
1387      Width = Target->getLongWidth();
1388      Align = Target->getLongAlign();
1389      break;
1390    case BuiltinType::ULongLong:
1391    case BuiltinType::LongLong:
1392      Width = Target->getLongLongWidth();
1393      Align = Target->getLongLongAlign();
1394      break;
1395    case BuiltinType::Int128:
1396    case BuiltinType::UInt128:
1397      Width = 128;
1398      Align = 128; // int128_t is 128-bit aligned on all targets.
1399      break;
1400    case BuiltinType::Half:
1401      Width = Target->getHalfWidth();
1402      Align = Target->getHalfAlign();
1403      break;
1404    case BuiltinType::Float:
1405      Width = Target->getFloatWidth();
1406      Align = Target->getFloatAlign();
1407      break;
1408    case BuiltinType::Double:
1409      Width = Target->getDoubleWidth();
1410      Align = Target->getDoubleAlign();
1411      break;
1412    case BuiltinType::LongDouble:
1413      Width = Target->getLongDoubleWidth();
1414      Align = Target->getLongDoubleAlign();
1415      break;
1416    case BuiltinType::NullPtr:
1417      Width = Target->getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
1418      Align = Target->getPointerAlign(0); //   == sizeof(void*)
1419      break;
1420    case BuiltinType::ObjCId:
1421    case BuiltinType::ObjCClass:
1422    case BuiltinType::ObjCSel:
1423      Width = Target->getPointerWidth(0);
1424      Align = Target->getPointerAlign(0);
1425      break;
1426    case BuiltinType::OCLImage1d:
1427    case BuiltinType::OCLImage1dArray:
1428    case BuiltinType::OCLImage1dBuffer:
1429    case BuiltinType::OCLImage2d:
1430    case BuiltinType::OCLImage2dArray:
1431    case BuiltinType::OCLImage3d:
1432      // Currently these types are pointers to opaque types.
1433      Width = Target->getPointerWidth(0);
1434      Align = Target->getPointerAlign(0);
1435      break;
1436    }
1437    break;
1438  case Type::ObjCObjectPointer:
1439    Width = Target->getPointerWidth(0);
1440    Align = Target->getPointerAlign(0);
1441    break;
1442  case Type::BlockPointer: {
1443    unsigned AS = getTargetAddressSpace(
1444        cast<BlockPointerType>(T)->getPointeeType());
1445    Width = Target->getPointerWidth(AS);
1446    Align = Target->getPointerAlign(AS);
1447    break;
1448  }
1449  case Type::LValueReference:
1450  case Type::RValueReference: {
1451    // alignof and sizeof should never enter this code path here, so we go
1452    // the pointer route.
1453    unsigned AS = getTargetAddressSpace(
1454        cast<ReferenceType>(T)->getPointeeType());
1455    Width = Target->getPointerWidth(AS);
1456    Align = Target->getPointerAlign(AS);
1457    break;
1458  }
1459  case Type::Pointer: {
1460    unsigned AS = getTargetAddressSpace(cast<PointerType>(T)->getPointeeType());
1461    Width = Target->getPointerWidth(AS);
1462    Align = Target->getPointerAlign(AS);
1463    break;
1464  }
1465  case Type::MemberPointer: {
1466    const MemberPointerType *MPT = cast<MemberPointerType>(T);
1467    std::pair<uint64_t, unsigned> PtrDiffInfo =
1468      getTypeInfo(getPointerDiffType());
1469    Width = PtrDiffInfo.first * ABI->getMemberPointerSize(MPT);
1470    Align = PtrDiffInfo.second;
1471    break;
1472  }
1473  case Type::Complex: {
1474    // Complex types have the same alignment as their elements, but twice the
1475    // size.
1476    std::pair<uint64_t, unsigned> EltInfo =
1477      getTypeInfo(cast<ComplexType>(T)->getElementType());
1478    Width = EltInfo.first*2;
1479    Align = EltInfo.second;
1480    break;
1481  }
1482  case Type::ObjCObject:
1483    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
1484  case Type::ObjCInterface: {
1485    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
1486    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
1487    Width = toBits(Layout.getSize());
1488    Align = toBits(Layout.getAlignment());
1489    break;
1490  }
1491  case Type::Record:
1492  case Type::Enum: {
1493    const TagType *TT = cast<TagType>(T);
1494
1495    if (TT->getDecl()->isInvalidDecl()) {
1496      Width = 8;
1497      Align = 8;
1498      break;
1499    }
1500
1501    if (const EnumType *ET = dyn_cast<EnumType>(TT))
1502      return getTypeInfo(ET->getDecl()->getIntegerType());
1503
1504    const RecordType *RT = cast<RecordType>(TT);
1505    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
1506    Width = toBits(Layout.getSize());
1507    Align = toBits(Layout.getAlignment());
1508    break;
1509  }
1510
1511  case Type::SubstTemplateTypeParm:
1512    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
1513                       getReplacementType().getTypePtr());
1514
1515  case Type::Auto: {
1516    const AutoType *A = cast<AutoType>(T);
1517    assert(A->isDeduced() && "Cannot request the size of a dependent type");
1518    return getTypeInfo(A->getDeducedType().getTypePtr());
1519  }
1520
1521  case Type::Paren:
1522    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
1523
1524  case Type::Typedef: {
1525    const TypedefNameDecl *Typedef = cast<TypedefType>(T)->getDecl();
1526    std::pair<uint64_t, unsigned> Info
1527      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
1528    // If the typedef has an aligned attribute on it, it overrides any computed
1529    // alignment we have.  This violates the GCC documentation (which says that
1530    // attribute(aligned) can only round up) but matches its implementation.
1531    if (unsigned AttrAlign = Typedef->getMaxAlignment())
1532      Align = AttrAlign;
1533    else
1534      Align = Info.second;
1535    Width = Info.first;
1536    break;
1537  }
1538
1539  case Type::TypeOfExpr:
1540    return getTypeInfo(cast<TypeOfExprType>(T)->getUnderlyingExpr()->getType()
1541                         .getTypePtr());
1542
1543  case Type::TypeOf:
1544    return getTypeInfo(cast<TypeOfType>(T)->getUnderlyingType().getTypePtr());
1545
1546  case Type::Decltype:
1547    return getTypeInfo(cast<DecltypeType>(T)->getUnderlyingExpr()->getType()
1548                        .getTypePtr());
1549
1550  case Type::UnaryTransform:
1551    return getTypeInfo(cast<UnaryTransformType>(T)->getUnderlyingType());
1552
1553  case Type::Elaborated:
1554    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
1555
1556  case Type::Attributed:
1557    return getTypeInfo(
1558                  cast<AttributedType>(T)->getEquivalentType().getTypePtr());
1559
1560  case Type::TemplateSpecialization: {
1561    assert(getCanonicalType(T) != T &&
1562           "Cannot request the size of a dependent type");
1563    const TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T);
1564    // A type alias template specialization may refer to a typedef with the
1565    // aligned attribute on it.
1566    if (TST->isTypeAlias())
1567      return getTypeInfo(TST->getAliasedType().getTypePtr());
1568    else
1569      return getTypeInfo(getCanonicalType(T));
1570  }
1571
1572  case Type::Atomic: {
1573    std::pair<uint64_t, unsigned> Info
1574      = getTypeInfo(cast<AtomicType>(T)->getValueType());
1575    Width = Info.first;
1576    Align = Info.second;
1577    if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth() &&
1578        llvm::isPowerOf2_64(Width)) {
1579      // We can potentially perform lock-free atomic operations for this
1580      // type; promote the alignment appropriately.
1581      // FIXME: We could potentially promote the width here as well...
1582      // is that worthwhile?  (Non-struct atomic types generally have
1583      // power-of-two size anyway, but structs might not.  Requires a bit
1584      // of implementation work to make sure we zero out the extra bits.)
1585      Align = static_cast<unsigned>(Width);
1586    }
1587  }
1588
1589  }
1590
1591  assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
1592  return std::make_pair(Width, Align);
1593}
1594
1595/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1596CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1597  return CharUnits::fromQuantity(BitSize / getCharWidth());
1598}
1599
1600/// toBits - Convert a size in characters to a size in characters.
1601int64_t ASTContext::toBits(CharUnits CharSize) const {
1602  return CharSize.getQuantity() * getCharWidth();
1603}
1604
1605/// getTypeSizeInChars - Return the size of the specified type, in characters.
1606/// This method does not work on incomplete types.
1607CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1608  return toCharUnitsFromBits(getTypeSize(T));
1609}
1610CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1611  return toCharUnitsFromBits(getTypeSize(T));
1612}
1613
1614/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1615/// characters. This method does not work on incomplete types.
1616CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1617  return toCharUnitsFromBits(getTypeAlign(T));
1618}
1619CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1620  return toCharUnitsFromBits(getTypeAlign(T));
1621}
1622
1623/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1624/// type for the current target in bits.  This can be different than the ABI
1625/// alignment in cases where it is beneficial for performance to overalign
1626/// a data type.
1627unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1628  unsigned ABIAlign = getTypeAlign(T);
1629
1630  // Double and long long should be naturally aligned if possible.
1631  if (const ComplexType* CT = T->getAs<ComplexType>())
1632    T = CT->getElementType().getTypePtr();
1633  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1634      T->isSpecificBuiltinType(BuiltinType::LongLong) ||
1635      T->isSpecificBuiltinType(BuiltinType::ULongLong))
1636    return std::max(ABIAlign, (unsigned)getTypeSize(T));
1637
1638  return ABIAlign;
1639}
1640
1641/// DeepCollectObjCIvars -
1642/// This routine first collects all declared, but not synthesized, ivars in
1643/// super class and then collects all ivars, including those synthesized for
1644/// current class. This routine is used for implementation of current class
1645/// when all ivars, declared and synthesized are known.
1646///
1647void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1648                                      bool leafClass,
1649                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1650  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1651    DeepCollectObjCIvars(SuperClass, false, Ivars);
1652  if (!leafClass) {
1653    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
1654         E = OI->ivar_end(); I != E; ++I)
1655      Ivars.push_back(*I);
1656  } else {
1657    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1658    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1659         Iv= Iv->getNextIvar())
1660      Ivars.push_back(Iv);
1661  }
1662}
1663
1664/// CollectInheritedProtocols - Collect all protocols in current class and
1665/// those inherited by it.
1666void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1667                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1668  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1669    // We can use protocol_iterator here instead of
1670    // all_referenced_protocol_iterator since we are walking all categories.
1671    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
1672         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
1673      ObjCProtocolDecl *Proto = (*P);
1674      Protocols.insert(Proto->getCanonicalDecl());
1675      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1676           PE = Proto->protocol_end(); P != PE; ++P) {
1677        Protocols.insert((*P)->getCanonicalDecl());
1678        CollectInheritedProtocols(*P, Protocols);
1679      }
1680    }
1681
1682    // Categories of this Interface.
1683    for (const ObjCCategoryDecl *CDeclChain = OI->getCategoryList();
1684         CDeclChain; CDeclChain = CDeclChain->getNextClassCategory())
1685      CollectInheritedProtocols(CDeclChain, Protocols);
1686    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1687      while (SD) {
1688        CollectInheritedProtocols(SD, Protocols);
1689        SD = SD->getSuperClass();
1690      }
1691  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1692    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
1693         PE = OC->protocol_end(); P != PE; ++P) {
1694      ObjCProtocolDecl *Proto = (*P);
1695      Protocols.insert(Proto->getCanonicalDecl());
1696      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1697           PE = Proto->protocol_end(); P != PE; ++P)
1698        CollectInheritedProtocols(*P, Protocols);
1699    }
1700  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
1701    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
1702         PE = OP->protocol_end(); P != PE; ++P) {
1703      ObjCProtocolDecl *Proto = (*P);
1704      Protocols.insert(Proto->getCanonicalDecl());
1705      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1706           PE = Proto->protocol_end(); P != PE; ++P)
1707        CollectInheritedProtocols(*P, Protocols);
1708    }
1709  }
1710}
1711
1712unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
1713  unsigned count = 0;
1714  // Count ivars declared in class extension.
1715  for (const ObjCCategoryDecl *CDecl = OI->getFirstClassExtension(); CDecl;
1716       CDecl = CDecl->getNextClassExtension())
1717    count += CDecl->ivar_size();
1718
1719  // Count ivar defined in this class's implementation.  This
1720  // includes synthesized ivars.
1721  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
1722    count += ImplDecl->ivar_size();
1723
1724  return count;
1725}
1726
1727bool ASTContext::isSentinelNullExpr(const Expr *E) {
1728  if (!E)
1729    return false;
1730
1731  // nullptr_t is always treated as null.
1732  if (E->getType()->isNullPtrType()) return true;
1733
1734  if (E->getType()->isAnyPointerType() &&
1735      E->IgnoreParenCasts()->isNullPointerConstant(*this,
1736                                                Expr::NPC_ValueDependentIsNull))
1737    return true;
1738
1739  // Unfortunately, __null has type 'int'.
1740  if (isa<GNUNullExpr>(E)) return true;
1741
1742  return false;
1743}
1744
1745/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
1746ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
1747  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1748    I = ObjCImpls.find(D);
1749  if (I != ObjCImpls.end())
1750    return cast<ObjCImplementationDecl>(I->second);
1751  return 0;
1752}
1753/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
1754ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
1755  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1756    I = ObjCImpls.find(D);
1757  if (I != ObjCImpls.end())
1758    return cast<ObjCCategoryImplDecl>(I->second);
1759  return 0;
1760}
1761
1762/// \brief Set the implementation of ObjCInterfaceDecl.
1763void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1764                           ObjCImplementationDecl *ImplD) {
1765  assert(IFaceD && ImplD && "Passed null params");
1766  ObjCImpls[IFaceD] = ImplD;
1767}
1768/// \brief Set the implementation of ObjCCategoryDecl.
1769void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1770                           ObjCCategoryImplDecl *ImplD) {
1771  assert(CatD && ImplD && "Passed null params");
1772  ObjCImpls[CatD] = ImplD;
1773}
1774
1775ObjCInterfaceDecl *ASTContext::getObjContainingInterface(NamedDecl *ND) const {
1776  if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(ND->getDeclContext()))
1777    return ID;
1778  if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(ND->getDeclContext()))
1779    return CD->getClassInterface();
1780  if (ObjCImplDecl *IMD = dyn_cast<ObjCImplDecl>(ND->getDeclContext()))
1781    return IMD->getClassInterface();
1782
1783  return 0;
1784}
1785
1786/// \brief Get the copy initialization expression of VarDecl,or NULL if
1787/// none exists.
1788Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
1789  assert(VD && "Passed null params");
1790  assert(VD->hasAttr<BlocksAttr>() &&
1791         "getBlockVarCopyInits - not __block var");
1792  llvm::DenseMap<const VarDecl*, Expr*>::iterator
1793    I = BlockVarCopyInits.find(VD);
1794  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : 0;
1795}
1796
1797/// \brief Set the copy inialization expression of a block var decl.
1798void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
1799  assert(VD && Init && "Passed null params");
1800  assert(VD->hasAttr<BlocksAttr>() &&
1801         "setBlockVarCopyInits - not __block var");
1802  BlockVarCopyInits[VD] = Init;
1803}
1804
1805TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1806                                                 unsigned DataSize) const {
1807  if (!DataSize)
1808    DataSize = TypeLoc::getFullDataSizeForType(T);
1809  else
1810    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1811           "incorrect data size provided to CreateTypeSourceInfo!");
1812
1813  TypeSourceInfo *TInfo =
1814    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1815  new (TInfo) TypeSourceInfo(T);
1816  return TInfo;
1817}
1818
1819TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1820                                                     SourceLocation L) const {
1821  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1822  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
1823  return DI;
1824}
1825
1826const ASTRecordLayout &
1827ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
1828  return getObjCLayout(D, 0);
1829}
1830
1831const ASTRecordLayout &
1832ASTContext::getASTObjCImplementationLayout(
1833                                        const ObjCImplementationDecl *D) const {
1834  return getObjCLayout(D->getClassInterface(), D);
1835}
1836
1837//===----------------------------------------------------------------------===//
1838//                   Type creation/memoization methods
1839//===----------------------------------------------------------------------===//
1840
1841QualType
1842ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
1843  unsigned fastQuals = quals.getFastQualifiers();
1844  quals.removeFastQualifiers();
1845
1846  // Check if we've already instantiated this type.
1847  llvm::FoldingSetNodeID ID;
1848  ExtQuals::Profile(ID, baseType, quals);
1849  void *insertPos = 0;
1850  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
1851    assert(eq->getQualifiers() == quals);
1852    return QualType(eq, fastQuals);
1853  }
1854
1855  // If the base type is not canonical, make the appropriate canonical type.
1856  QualType canon;
1857  if (!baseType->isCanonicalUnqualified()) {
1858    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
1859    canonSplit.Quals.addConsistentQualifiers(quals);
1860    canon = getExtQualType(canonSplit.Ty, canonSplit.Quals);
1861
1862    // Re-find the insert position.
1863    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
1864  }
1865
1866  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
1867  ExtQualNodes.InsertNode(eq, insertPos);
1868  return QualType(eq, fastQuals);
1869}
1870
1871QualType
1872ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
1873  QualType CanT = getCanonicalType(T);
1874  if (CanT.getAddressSpace() == AddressSpace)
1875    return T;
1876
1877  // If we are composing extended qualifiers together, merge together
1878  // into one ExtQuals node.
1879  QualifierCollector Quals;
1880  const Type *TypeNode = Quals.strip(T);
1881
1882  // If this type already has an address space specified, it cannot get
1883  // another one.
1884  assert(!Quals.hasAddressSpace() &&
1885         "Type cannot be in multiple addr spaces!");
1886  Quals.addAddressSpace(AddressSpace);
1887
1888  return getExtQualType(TypeNode, Quals);
1889}
1890
1891QualType ASTContext::getObjCGCQualType(QualType T,
1892                                       Qualifiers::GC GCAttr) const {
1893  QualType CanT = getCanonicalType(T);
1894  if (CanT.getObjCGCAttr() == GCAttr)
1895    return T;
1896
1897  if (const PointerType *ptr = T->getAs<PointerType>()) {
1898    QualType Pointee = ptr->getPointeeType();
1899    if (Pointee->isAnyPointerType()) {
1900      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
1901      return getPointerType(ResultType);
1902    }
1903  }
1904
1905  // If we are composing extended qualifiers together, merge together
1906  // into one ExtQuals node.
1907  QualifierCollector Quals;
1908  const Type *TypeNode = Quals.strip(T);
1909
1910  // If this type already has an ObjCGC specified, it cannot get
1911  // another one.
1912  assert(!Quals.hasObjCGCAttr() &&
1913         "Type cannot have multiple ObjCGCs!");
1914  Quals.addObjCGCAttr(GCAttr);
1915
1916  return getExtQualType(TypeNode, Quals);
1917}
1918
1919const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
1920                                                   FunctionType::ExtInfo Info) {
1921  if (T->getExtInfo() == Info)
1922    return T;
1923
1924  QualType Result;
1925  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
1926    Result = getFunctionNoProtoType(FNPT->getResultType(), Info);
1927  } else {
1928    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
1929    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
1930    EPI.ExtInfo = Info;
1931    Result = getFunctionType(FPT->getResultType(), FPT->arg_type_begin(),
1932                             FPT->getNumArgs(), EPI);
1933  }
1934
1935  return cast<FunctionType>(Result.getTypePtr());
1936}
1937
1938/// getComplexType - Return the uniqued reference to the type for a complex
1939/// number with the specified element type.
1940QualType ASTContext::getComplexType(QualType T) const {
1941  // Unique pointers, to guarantee there is only one pointer of a particular
1942  // structure.
1943  llvm::FoldingSetNodeID ID;
1944  ComplexType::Profile(ID, T);
1945
1946  void *InsertPos = 0;
1947  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
1948    return QualType(CT, 0);
1949
1950  // If the pointee type isn't canonical, this won't be a canonical type either,
1951  // so fill in the canonical type field.
1952  QualType Canonical;
1953  if (!T.isCanonical()) {
1954    Canonical = getComplexType(getCanonicalType(T));
1955
1956    // Get the new insert position for the node we care about.
1957    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
1958    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1959  }
1960  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
1961  Types.push_back(New);
1962  ComplexTypes.InsertNode(New, InsertPos);
1963  return QualType(New, 0);
1964}
1965
1966/// getPointerType - Return the uniqued reference to the type for a pointer to
1967/// the specified type.
1968QualType ASTContext::getPointerType(QualType T) const {
1969  // Unique pointers, to guarantee there is only one pointer of a particular
1970  // structure.
1971  llvm::FoldingSetNodeID ID;
1972  PointerType::Profile(ID, T);
1973
1974  void *InsertPos = 0;
1975  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
1976    return QualType(PT, 0);
1977
1978  // If the pointee type isn't canonical, this won't be a canonical type either,
1979  // so fill in the canonical type field.
1980  QualType Canonical;
1981  if (!T.isCanonical()) {
1982    Canonical = getPointerType(getCanonicalType(T));
1983
1984    // Get the new insert position for the node we care about.
1985    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
1986    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
1987  }
1988  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
1989  Types.push_back(New);
1990  PointerTypes.InsertNode(New, InsertPos);
1991  return QualType(New, 0);
1992}
1993
1994/// getBlockPointerType - Return the uniqued reference to the type for
1995/// a pointer to the specified block.
1996QualType ASTContext::getBlockPointerType(QualType T) const {
1997  assert(T->isFunctionType() && "block of function types only");
1998  // Unique pointers, to guarantee there is only one block of a particular
1999  // structure.
2000  llvm::FoldingSetNodeID ID;
2001  BlockPointerType::Profile(ID, T);
2002
2003  void *InsertPos = 0;
2004  if (BlockPointerType *PT =
2005        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2006    return QualType(PT, 0);
2007
2008  // If the block pointee type isn't canonical, this won't be a canonical
2009  // type either so fill in the canonical type field.
2010  QualType Canonical;
2011  if (!T.isCanonical()) {
2012    Canonical = getBlockPointerType(getCanonicalType(T));
2013
2014    // Get the new insert position for the node we care about.
2015    BlockPointerType *NewIP =
2016      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2017    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2018  }
2019  BlockPointerType *New
2020    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
2021  Types.push_back(New);
2022  BlockPointerTypes.InsertNode(New, InsertPos);
2023  return QualType(New, 0);
2024}
2025
2026/// getLValueReferenceType - Return the uniqued reference to the type for an
2027/// lvalue reference to the specified type.
2028QualType
2029ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
2030  assert(getCanonicalType(T) != OverloadTy &&
2031         "Unresolved overloaded function type");
2032
2033  // Unique pointers, to guarantee there is only one pointer of a particular
2034  // structure.
2035  llvm::FoldingSetNodeID ID;
2036  ReferenceType::Profile(ID, T, SpelledAsLValue);
2037
2038  void *InsertPos = 0;
2039  if (LValueReferenceType *RT =
2040        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
2041    return QualType(RT, 0);
2042
2043  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
2044
2045  // If the referencee type isn't canonical, this won't be a canonical type
2046  // either, so fill in the canonical type field.
2047  QualType Canonical;
2048  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
2049    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
2050    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
2051
2052    // Get the new insert position for the node we care about.
2053    LValueReferenceType *NewIP =
2054      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
2055    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2056  }
2057
2058  LValueReferenceType *New
2059    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
2060                                                     SpelledAsLValue);
2061  Types.push_back(New);
2062  LValueReferenceTypes.InsertNode(New, InsertPos);
2063
2064  return QualType(New, 0);
2065}
2066
2067/// getRValueReferenceType - Return the uniqued reference to the type for an
2068/// rvalue reference to the specified type.
2069QualType ASTContext::getRValueReferenceType(QualType T) const {
2070  // Unique pointers, to guarantee there is only one pointer of a particular
2071  // structure.
2072  llvm::FoldingSetNodeID ID;
2073  ReferenceType::Profile(ID, T, false);
2074
2075  void *InsertPos = 0;
2076  if (RValueReferenceType *RT =
2077        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
2078    return QualType(RT, 0);
2079
2080  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
2081
2082  // If the referencee type isn't canonical, this won't be a canonical type
2083  // either, so fill in the canonical type field.
2084  QualType Canonical;
2085  if (InnerRef || !T.isCanonical()) {
2086    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
2087    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
2088
2089    // Get the new insert position for the node we care about.
2090    RValueReferenceType *NewIP =
2091      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
2092    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2093  }
2094
2095  RValueReferenceType *New
2096    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
2097  Types.push_back(New);
2098  RValueReferenceTypes.InsertNode(New, InsertPos);
2099  return QualType(New, 0);
2100}
2101
2102/// getMemberPointerType - Return the uniqued reference to the type for a
2103/// member pointer to the specified type, in the specified class.
2104QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
2105  // Unique pointers, to guarantee there is only one pointer of a particular
2106  // structure.
2107  llvm::FoldingSetNodeID ID;
2108  MemberPointerType::Profile(ID, T, Cls);
2109
2110  void *InsertPos = 0;
2111  if (MemberPointerType *PT =
2112      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2113    return QualType(PT, 0);
2114
2115  // If the pointee or class type isn't canonical, this won't be a canonical
2116  // type either, so fill in the canonical type field.
2117  QualType Canonical;
2118  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
2119    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
2120
2121    // Get the new insert position for the node we care about.
2122    MemberPointerType *NewIP =
2123      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2124    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2125  }
2126  MemberPointerType *New
2127    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
2128  Types.push_back(New);
2129  MemberPointerTypes.InsertNode(New, InsertPos);
2130  return QualType(New, 0);
2131}
2132
2133/// getConstantArrayType - Return the unique reference to the type for an
2134/// array of the specified element type.
2135QualType ASTContext::getConstantArrayType(QualType EltTy,
2136                                          const llvm::APInt &ArySizeIn,
2137                                          ArrayType::ArraySizeModifier ASM,
2138                                          unsigned IndexTypeQuals) const {
2139  assert((EltTy->isDependentType() ||
2140          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
2141         "Constant array of VLAs is illegal!");
2142
2143  // Convert the array size into a canonical width matching the pointer size for
2144  // the target.
2145  llvm::APInt ArySize(ArySizeIn);
2146  ArySize =
2147    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
2148
2149  llvm::FoldingSetNodeID ID;
2150  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
2151
2152  void *InsertPos = 0;
2153  if (ConstantArrayType *ATP =
2154      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
2155    return QualType(ATP, 0);
2156
2157  // If the element type isn't canonical or has qualifiers, this won't
2158  // be a canonical type either, so fill in the canonical type field.
2159  QualType Canon;
2160  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2161    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2162    Canon = getConstantArrayType(QualType(canonSplit.Ty, 0), ArySize,
2163                                 ASM, IndexTypeQuals);
2164    Canon = getQualifiedType(Canon, canonSplit.Quals);
2165
2166    // Get the new insert position for the node we care about.
2167    ConstantArrayType *NewIP =
2168      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
2169    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2170  }
2171
2172  ConstantArrayType *New = new(*this,TypeAlignment)
2173    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
2174  ConstantArrayTypes.InsertNode(New, InsertPos);
2175  Types.push_back(New);
2176  return QualType(New, 0);
2177}
2178
2179/// getVariableArrayDecayedType - Turns the given type, which may be
2180/// variably-modified, into the corresponding type with all the known
2181/// sizes replaced with [*].
2182QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
2183  // Vastly most common case.
2184  if (!type->isVariablyModifiedType()) return type;
2185
2186  QualType result;
2187
2188  SplitQualType split = type.getSplitDesugaredType();
2189  const Type *ty = split.Ty;
2190  switch (ty->getTypeClass()) {
2191#define TYPE(Class, Base)
2192#define ABSTRACT_TYPE(Class, Base)
2193#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
2194#include "clang/AST/TypeNodes.def"
2195    llvm_unreachable("didn't desugar past all non-canonical types?");
2196
2197  // These types should never be variably-modified.
2198  case Type::Builtin:
2199  case Type::Complex:
2200  case Type::Vector:
2201  case Type::ExtVector:
2202  case Type::DependentSizedExtVector:
2203  case Type::ObjCObject:
2204  case Type::ObjCInterface:
2205  case Type::ObjCObjectPointer:
2206  case Type::Record:
2207  case Type::Enum:
2208  case Type::UnresolvedUsing:
2209  case Type::TypeOfExpr:
2210  case Type::TypeOf:
2211  case Type::Decltype:
2212  case Type::UnaryTransform:
2213  case Type::DependentName:
2214  case Type::InjectedClassName:
2215  case Type::TemplateSpecialization:
2216  case Type::DependentTemplateSpecialization:
2217  case Type::TemplateTypeParm:
2218  case Type::SubstTemplateTypeParmPack:
2219  case Type::Auto:
2220  case Type::PackExpansion:
2221    llvm_unreachable("type should never be variably-modified");
2222
2223  // These types can be variably-modified but should never need to
2224  // further decay.
2225  case Type::FunctionNoProto:
2226  case Type::FunctionProto:
2227  case Type::BlockPointer:
2228  case Type::MemberPointer:
2229    return type;
2230
2231  // These types can be variably-modified.  All these modifications
2232  // preserve structure except as noted by comments.
2233  // TODO: if we ever care about optimizing VLAs, there are no-op
2234  // optimizations available here.
2235  case Type::Pointer:
2236    result = getPointerType(getVariableArrayDecayedType(
2237                              cast<PointerType>(ty)->getPointeeType()));
2238    break;
2239
2240  case Type::LValueReference: {
2241    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
2242    result = getLValueReferenceType(
2243                 getVariableArrayDecayedType(lv->getPointeeType()),
2244                                    lv->isSpelledAsLValue());
2245    break;
2246  }
2247
2248  case Type::RValueReference: {
2249    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
2250    result = getRValueReferenceType(
2251                 getVariableArrayDecayedType(lv->getPointeeType()));
2252    break;
2253  }
2254
2255  case Type::Atomic: {
2256    const AtomicType *at = cast<AtomicType>(ty);
2257    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
2258    break;
2259  }
2260
2261  case Type::ConstantArray: {
2262    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
2263    result = getConstantArrayType(
2264                 getVariableArrayDecayedType(cat->getElementType()),
2265                                  cat->getSize(),
2266                                  cat->getSizeModifier(),
2267                                  cat->getIndexTypeCVRQualifiers());
2268    break;
2269  }
2270
2271  case Type::DependentSizedArray: {
2272    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
2273    result = getDependentSizedArrayType(
2274                 getVariableArrayDecayedType(dat->getElementType()),
2275                                        dat->getSizeExpr(),
2276                                        dat->getSizeModifier(),
2277                                        dat->getIndexTypeCVRQualifiers(),
2278                                        dat->getBracketsRange());
2279    break;
2280  }
2281
2282  // Turn incomplete types into [*] types.
2283  case Type::IncompleteArray: {
2284    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
2285    result = getVariableArrayType(
2286                 getVariableArrayDecayedType(iat->getElementType()),
2287                                  /*size*/ 0,
2288                                  ArrayType::Normal,
2289                                  iat->getIndexTypeCVRQualifiers(),
2290                                  SourceRange());
2291    break;
2292  }
2293
2294  // Turn VLA types into [*] types.
2295  case Type::VariableArray: {
2296    const VariableArrayType *vat = cast<VariableArrayType>(ty);
2297    result = getVariableArrayType(
2298                 getVariableArrayDecayedType(vat->getElementType()),
2299                                  /*size*/ 0,
2300                                  ArrayType::Star,
2301                                  vat->getIndexTypeCVRQualifiers(),
2302                                  vat->getBracketsRange());
2303    break;
2304  }
2305  }
2306
2307  // Apply the top-level qualifiers from the original.
2308  return getQualifiedType(result, split.Quals);
2309}
2310
2311/// getVariableArrayType - Returns a non-unique reference to the type for a
2312/// variable array of the specified element type.
2313QualType ASTContext::getVariableArrayType(QualType EltTy,
2314                                          Expr *NumElts,
2315                                          ArrayType::ArraySizeModifier ASM,
2316                                          unsigned IndexTypeQuals,
2317                                          SourceRange Brackets) const {
2318  // Since we don't unique expressions, it isn't possible to unique VLA's
2319  // that have an expression provided for their size.
2320  QualType Canon;
2321
2322  // Be sure to pull qualifiers off the element type.
2323  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2324    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2325    Canon = getVariableArrayType(QualType(canonSplit.Ty, 0), NumElts, ASM,
2326                                 IndexTypeQuals, Brackets);
2327    Canon = getQualifiedType(Canon, canonSplit.Quals);
2328  }
2329
2330  VariableArrayType *New = new(*this, TypeAlignment)
2331    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
2332
2333  VariableArrayTypes.push_back(New);
2334  Types.push_back(New);
2335  return QualType(New, 0);
2336}
2337
2338/// getDependentSizedArrayType - Returns a non-unique reference to
2339/// the type for a dependently-sized array of the specified element
2340/// type.
2341QualType ASTContext::getDependentSizedArrayType(QualType elementType,
2342                                                Expr *numElements,
2343                                                ArrayType::ArraySizeModifier ASM,
2344                                                unsigned elementTypeQuals,
2345                                                SourceRange brackets) const {
2346  assert((!numElements || numElements->isTypeDependent() ||
2347          numElements->isValueDependent()) &&
2348         "Size must be type- or value-dependent!");
2349
2350  // Dependently-sized array types that do not have a specified number
2351  // of elements will have their sizes deduced from a dependent
2352  // initializer.  We do no canonicalization here at all, which is okay
2353  // because they can't be used in most locations.
2354  if (!numElements) {
2355    DependentSizedArrayType *newType
2356      = new (*this, TypeAlignment)
2357          DependentSizedArrayType(*this, elementType, QualType(),
2358                                  numElements, ASM, elementTypeQuals,
2359                                  brackets);
2360    Types.push_back(newType);
2361    return QualType(newType, 0);
2362  }
2363
2364  // Otherwise, we actually build a new type every time, but we
2365  // also build a canonical type.
2366
2367  SplitQualType canonElementType = getCanonicalType(elementType).split();
2368
2369  void *insertPos = 0;
2370  llvm::FoldingSetNodeID ID;
2371  DependentSizedArrayType::Profile(ID, *this,
2372                                   QualType(canonElementType.Ty, 0),
2373                                   ASM, elementTypeQuals, numElements);
2374
2375  // Look for an existing type with these properties.
2376  DependentSizedArrayType *canonTy =
2377    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2378
2379  // If we don't have one, build one.
2380  if (!canonTy) {
2381    canonTy = new (*this, TypeAlignment)
2382      DependentSizedArrayType(*this, QualType(canonElementType.Ty, 0),
2383                              QualType(), numElements, ASM, elementTypeQuals,
2384                              brackets);
2385    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
2386    Types.push_back(canonTy);
2387  }
2388
2389  // Apply qualifiers from the element type to the array.
2390  QualType canon = getQualifiedType(QualType(canonTy,0),
2391                                    canonElementType.Quals);
2392
2393  // If we didn't need extra canonicalization for the element type,
2394  // then just use that as our result.
2395  if (QualType(canonElementType.Ty, 0) == elementType)
2396    return canon;
2397
2398  // Otherwise, we need to build a type which follows the spelling
2399  // of the element type.
2400  DependentSizedArrayType *sugaredType
2401    = new (*this, TypeAlignment)
2402        DependentSizedArrayType(*this, elementType, canon, numElements,
2403                                ASM, elementTypeQuals, brackets);
2404  Types.push_back(sugaredType);
2405  return QualType(sugaredType, 0);
2406}
2407
2408QualType ASTContext::getIncompleteArrayType(QualType elementType,
2409                                            ArrayType::ArraySizeModifier ASM,
2410                                            unsigned elementTypeQuals) const {
2411  llvm::FoldingSetNodeID ID;
2412  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
2413
2414  void *insertPos = 0;
2415  if (IncompleteArrayType *iat =
2416       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
2417    return QualType(iat, 0);
2418
2419  // If the element type isn't canonical, this won't be a canonical type
2420  // either, so fill in the canonical type field.  We also have to pull
2421  // qualifiers off the element type.
2422  QualType canon;
2423
2424  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
2425    SplitQualType canonSplit = getCanonicalType(elementType).split();
2426    canon = getIncompleteArrayType(QualType(canonSplit.Ty, 0),
2427                                   ASM, elementTypeQuals);
2428    canon = getQualifiedType(canon, canonSplit.Quals);
2429
2430    // Get the new insert position for the node we care about.
2431    IncompleteArrayType *existing =
2432      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2433    assert(!existing && "Shouldn't be in the map!"); (void) existing;
2434  }
2435
2436  IncompleteArrayType *newType = new (*this, TypeAlignment)
2437    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
2438
2439  IncompleteArrayTypes.InsertNode(newType, insertPos);
2440  Types.push_back(newType);
2441  return QualType(newType, 0);
2442}
2443
2444/// getVectorType - Return the unique reference to a vector type of
2445/// the specified element type and size. VectorType must be a built-in type.
2446QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
2447                                   VectorType::VectorKind VecKind) const {
2448  assert(vecType->isBuiltinType());
2449
2450  // Check if we've already instantiated a vector of this type.
2451  llvm::FoldingSetNodeID ID;
2452  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
2453
2454  void *InsertPos = 0;
2455  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2456    return QualType(VTP, 0);
2457
2458  // If the element type isn't canonical, this won't be a canonical type either,
2459  // so fill in the canonical type field.
2460  QualType Canonical;
2461  if (!vecType.isCanonical()) {
2462    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
2463
2464    // Get the new insert position for the node we care about.
2465    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2466    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2467  }
2468  VectorType *New = new (*this, TypeAlignment)
2469    VectorType(vecType, NumElts, Canonical, VecKind);
2470  VectorTypes.InsertNode(New, InsertPos);
2471  Types.push_back(New);
2472  return QualType(New, 0);
2473}
2474
2475/// getExtVectorType - Return the unique reference to an extended vector type of
2476/// the specified element type and size. VectorType must be a built-in type.
2477QualType
2478ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
2479  assert(vecType->isBuiltinType() || vecType->isDependentType());
2480
2481  // Check if we've already instantiated a vector of this type.
2482  llvm::FoldingSetNodeID ID;
2483  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
2484                      VectorType::GenericVector);
2485  void *InsertPos = 0;
2486  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2487    return QualType(VTP, 0);
2488
2489  // If the element type isn't canonical, this won't be a canonical type either,
2490  // so fill in the canonical type field.
2491  QualType Canonical;
2492  if (!vecType.isCanonical()) {
2493    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
2494
2495    // Get the new insert position for the node we care about.
2496    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2497    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2498  }
2499  ExtVectorType *New = new (*this, TypeAlignment)
2500    ExtVectorType(vecType, NumElts, Canonical);
2501  VectorTypes.InsertNode(New, InsertPos);
2502  Types.push_back(New);
2503  return QualType(New, 0);
2504}
2505
2506QualType
2507ASTContext::getDependentSizedExtVectorType(QualType vecType,
2508                                           Expr *SizeExpr,
2509                                           SourceLocation AttrLoc) const {
2510  llvm::FoldingSetNodeID ID;
2511  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
2512                                       SizeExpr);
2513
2514  void *InsertPos = 0;
2515  DependentSizedExtVectorType *Canon
2516    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2517  DependentSizedExtVectorType *New;
2518  if (Canon) {
2519    // We already have a canonical version of this array type; use it as
2520    // the canonical type for a newly-built type.
2521    New = new (*this, TypeAlignment)
2522      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
2523                                  SizeExpr, AttrLoc);
2524  } else {
2525    QualType CanonVecTy = getCanonicalType(vecType);
2526    if (CanonVecTy == vecType) {
2527      New = new (*this, TypeAlignment)
2528        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
2529                                    AttrLoc);
2530
2531      DependentSizedExtVectorType *CanonCheck
2532        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2533      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
2534      (void)CanonCheck;
2535      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
2536    } else {
2537      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
2538                                                      SourceLocation());
2539      New = new (*this, TypeAlignment)
2540        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2541    }
2542  }
2543
2544  Types.push_back(New);
2545  return QualType(New, 0);
2546}
2547
2548/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
2549///
2550QualType
2551ASTContext::getFunctionNoProtoType(QualType ResultTy,
2552                                   const FunctionType::ExtInfo &Info) const {
2553  const CallingConv DefaultCC = Info.getCC();
2554  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2555                               CC_X86StdCall : DefaultCC;
2556  // Unique functions, to guarantee there is only one function of a particular
2557  // structure.
2558  llvm::FoldingSetNodeID ID;
2559  FunctionNoProtoType::Profile(ID, ResultTy, Info);
2560
2561  void *InsertPos = 0;
2562  if (FunctionNoProtoType *FT =
2563        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2564    return QualType(FT, 0);
2565
2566  QualType Canonical;
2567  if (!ResultTy.isCanonical() ||
2568      getCanonicalCallConv(CallConv) != CallConv) {
2569    Canonical =
2570      getFunctionNoProtoType(getCanonicalType(ResultTy),
2571                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
2572
2573    // Get the new insert position for the node we care about.
2574    FunctionNoProtoType *NewIP =
2575      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2576    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2577  }
2578
2579  FunctionProtoType::ExtInfo newInfo = Info.withCallingConv(CallConv);
2580  FunctionNoProtoType *New = new (*this, TypeAlignment)
2581    FunctionNoProtoType(ResultTy, Canonical, newInfo);
2582  Types.push_back(New);
2583  FunctionNoProtoTypes.InsertNode(New, InsertPos);
2584  return QualType(New, 0);
2585}
2586
2587/// getFunctionType - Return a normal function type with a typed argument
2588/// list.  isVariadic indicates whether the argument list includes '...'.
2589QualType
2590ASTContext::getFunctionType(QualType ResultTy,
2591                            const QualType *ArgArray, unsigned NumArgs,
2592                            const FunctionProtoType::ExtProtoInfo &EPI) const {
2593  // Unique functions, to guarantee there is only one function of a particular
2594  // structure.
2595  llvm::FoldingSetNodeID ID;
2596  FunctionProtoType::Profile(ID, ResultTy, ArgArray, NumArgs, EPI, *this);
2597
2598  void *InsertPos = 0;
2599  if (FunctionProtoType *FTP =
2600        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2601    return QualType(FTP, 0);
2602
2603  // Determine whether the type being created is already canonical or not.
2604  bool isCanonical =
2605    EPI.ExceptionSpecType == EST_None && ResultTy.isCanonical() &&
2606    !EPI.HasTrailingReturn;
2607  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
2608    if (!ArgArray[i].isCanonicalAsParam())
2609      isCanonical = false;
2610
2611  const CallingConv DefaultCC = EPI.ExtInfo.getCC();
2612  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2613                               CC_X86StdCall : DefaultCC;
2614
2615  // If this type isn't canonical, get the canonical version of it.
2616  // The exception spec is not part of the canonical type.
2617  QualType Canonical;
2618  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
2619    SmallVector<QualType, 16> CanonicalArgs;
2620    CanonicalArgs.reserve(NumArgs);
2621    for (unsigned i = 0; i != NumArgs; ++i)
2622      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
2623
2624    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
2625    CanonicalEPI.HasTrailingReturn = false;
2626    CanonicalEPI.ExceptionSpecType = EST_None;
2627    CanonicalEPI.NumExceptions = 0;
2628    CanonicalEPI.ExtInfo
2629      = CanonicalEPI.ExtInfo.withCallingConv(getCanonicalCallConv(CallConv));
2630
2631    Canonical = getFunctionType(getCanonicalType(ResultTy),
2632                                CanonicalArgs.data(), NumArgs,
2633                                CanonicalEPI);
2634
2635    // Get the new insert position for the node we care about.
2636    FunctionProtoType *NewIP =
2637      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2638    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2639  }
2640
2641  // FunctionProtoType objects are allocated with extra bytes after
2642  // them for three variable size arrays at the end:
2643  //  - parameter types
2644  //  - exception types
2645  //  - consumed-arguments flags
2646  // Instead of the exception types, there could be a noexcept
2647  // expression, or information used to resolve the exception
2648  // specification.
2649  size_t Size = sizeof(FunctionProtoType) +
2650                NumArgs * sizeof(QualType);
2651  if (EPI.ExceptionSpecType == EST_Dynamic) {
2652    Size += EPI.NumExceptions * sizeof(QualType);
2653  } else if (EPI.ExceptionSpecType == EST_ComputedNoexcept) {
2654    Size += sizeof(Expr*);
2655  } else if (EPI.ExceptionSpecType == EST_Uninstantiated) {
2656    Size += 2 * sizeof(FunctionDecl*);
2657  } else if (EPI.ExceptionSpecType == EST_Unevaluated) {
2658    Size += sizeof(FunctionDecl*);
2659  }
2660  if (EPI.ConsumedArguments)
2661    Size += NumArgs * sizeof(bool);
2662
2663  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
2664  FunctionProtoType::ExtProtoInfo newEPI = EPI;
2665  newEPI.ExtInfo = EPI.ExtInfo.withCallingConv(CallConv);
2666  new (FTP) FunctionProtoType(ResultTy, ArgArray, NumArgs, Canonical, newEPI);
2667  Types.push_back(FTP);
2668  FunctionProtoTypes.InsertNode(FTP, InsertPos);
2669  return QualType(FTP, 0);
2670}
2671
2672#ifndef NDEBUG
2673static bool NeedsInjectedClassNameType(const RecordDecl *D) {
2674  if (!isa<CXXRecordDecl>(D)) return false;
2675  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
2676  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
2677    return true;
2678  if (RD->getDescribedClassTemplate() &&
2679      !isa<ClassTemplateSpecializationDecl>(RD))
2680    return true;
2681  return false;
2682}
2683#endif
2684
2685/// getInjectedClassNameType - Return the unique reference to the
2686/// injected class name type for the specified templated declaration.
2687QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
2688                                              QualType TST) const {
2689  assert(NeedsInjectedClassNameType(Decl));
2690  if (Decl->TypeForDecl) {
2691    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2692  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDecl()) {
2693    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
2694    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2695    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2696  } else {
2697    Type *newType =
2698      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
2699    Decl->TypeForDecl = newType;
2700    Types.push_back(newType);
2701  }
2702  return QualType(Decl->TypeForDecl, 0);
2703}
2704
2705/// getTypeDeclType - Return the unique reference to the type for the
2706/// specified type declaration.
2707QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) const {
2708  assert(Decl && "Passed null for Decl param");
2709  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
2710
2711  if (const TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Decl))
2712    return getTypedefType(Typedef);
2713
2714  assert(!isa<TemplateTypeParmDecl>(Decl) &&
2715         "Template type parameter types are always available.");
2716
2717  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
2718    assert(!Record->getPreviousDecl() &&
2719           "struct/union has previous declaration");
2720    assert(!NeedsInjectedClassNameType(Record));
2721    return getRecordType(Record);
2722  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
2723    assert(!Enum->getPreviousDecl() &&
2724           "enum has previous declaration");
2725    return getEnumType(Enum);
2726  } else if (const UnresolvedUsingTypenameDecl *Using =
2727               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
2728    Type *newType = new (*this, TypeAlignment) UnresolvedUsingType(Using);
2729    Decl->TypeForDecl = newType;
2730    Types.push_back(newType);
2731  } else
2732    llvm_unreachable("TypeDecl without a type?");
2733
2734  return QualType(Decl->TypeForDecl, 0);
2735}
2736
2737/// getTypedefType - Return the unique reference to the type for the
2738/// specified typedef name decl.
2739QualType
2740ASTContext::getTypedefType(const TypedefNameDecl *Decl,
2741                           QualType Canonical) const {
2742  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2743
2744  if (Canonical.isNull())
2745    Canonical = getCanonicalType(Decl->getUnderlyingType());
2746  TypedefType *newType = new(*this, TypeAlignment)
2747    TypedefType(Type::Typedef, Decl, Canonical);
2748  Decl->TypeForDecl = newType;
2749  Types.push_back(newType);
2750  return QualType(newType, 0);
2751}
2752
2753QualType ASTContext::getRecordType(const RecordDecl *Decl) const {
2754  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2755
2756  if (const RecordDecl *PrevDecl = Decl->getPreviousDecl())
2757    if (PrevDecl->TypeForDecl)
2758      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2759
2760  RecordType *newType = new (*this, TypeAlignment) RecordType(Decl);
2761  Decl->TypeForDecl = newType;
2762  Types.push_back(newType);
2763  return QualType(newType, 0);
2764}
2765
2766QualType ASTContext::getEnumType(const EnumDecl *Decl) const {
2767  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2768
2769  if (const EnumDecl *PrevDecl = Decl->getPreviousDecl())
2770    if (PrevDecl->TypeForDecl)
2771      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2772
2773  EnumType *newType = new (*this, TypeAlignment) EnumType(Decl);
2774  Decl->TypeForDecl = newType;
2775  Types.push_back(newType);
2776  return QualType(newType, 0);
2777}
2778
2779QualType ASTContext::getAttributedType(AttributedType::Kind attrKind,
2780                                       QualType modifiedType,
2781                                       QualType equivalentType) {
2782  llvm::FoldingSetNodeID id;
2783  AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
2784
2785  void *insertPos = 0;
2786  AttributedType *type = AttributedTypes.FindNodeOrInsertPos(id, insertPos);
2787  if (type) return QualType(type, 0);
2788
2789  QualType canon = getCanonicalType(equivalentType);
2790  type = new (*this, TypeAlignment)
2791           AttributedType(canon, attrKind, modifiedType, equivalentType);
2792
2793  Types.push_back(type);
2794  AttributedTypes.InsertNode(type, insertPos);
2795
2796  return QualType(type, 0);
2797}
2798
2799
2800/// \brief Retrieve a substitution-result type.
2801QualType
2802ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
2803                                         QualType Replacement) const {
2804  assert(Replacement.isCanonical()
2805         && "replacement types must always be canonical");
2806
2807  llvm::FoldingSetNodeID ID;
2808  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
2809  void *InsertPos = 0;
2810  SubstTemplateTypeParmType *SubstParm
2811    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2812
2813  if (!SubstParm) {
2814    SubstParm = new (*this, TypeAlignment)
2815      SubstTemplateTypeParmType(Parm, Replacement);
2816    Types.push_back(SubstParm);
2817    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2818  }
2819
2820  return QualType(SubstParm, 0);
2821}
2822
2823/// \brief Retrieve a
2824QualType ASTContext::getSubstTemplateTypeParmPackType(
2825                                          const TemplateTypeParmType *Parm,
2826                                              const TemplateArgument &ArgPack) {
2827#ifndef NDEBUG
2828  for (TemplateArgument::pack_iterator P = ArgPack.pack_begin(),
2829                                    PEnd = ArgPack.pack_end();
2830       P != PEnd; ++P) {
2831    assert(P->getKind() == TemplateArgument::Type &&"Pack contains a non-type");
2832    assert(P->getAsType().isCanonical() && "Pack contains non-canonical type");
2833  }
2834#endif
2835
2836  llvm::FoldingSetNodeID ID;
2837  SubstTemplateTypeParmPackType::Profile(ID, Parm, ArgPack);
2838  void *InsertPos = 0;
2839  if (SubstTemplateTypeParmPackType *SubstParm
2840        = SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos))
2841    return QualType(SubstParm, 0);
2842
2843  QualType Canon;
2844  if (!Parm->isCanonicalUnqualified()) {
2845    Canon = getCanonicalType(QualType(Parm, 0));
2846    Canon = getSubstTemplateTypeParmPackType(cast<TemplateTypeParmType>(Canon),
2847                                             ArgPack);
2848    SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos);
2849  }
2850
2851  SubstTemplateTypeParmPackType *SubstParm
2852    = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
2853                                                               ArgPack);
2854  Types.push_back(SubstParm);
2855  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
2856  return QualType(SubstParm, 0);
2857}
2858
2859/// \brief Retrieve the template type parameter type for a template
2860/// parameter or parameter pack with the given depth, index, and (optionally)
2861/// name.
2862QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
2863                                             bool ParameterPack,
2864                                             TemplateTypeParmDecl *TTPDecl) const {
2865  llvm::FoldingSetNodeID ID;
2866  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, TTPDecl);
2867  void *InsertPos = 0;
2868  TemplateTypeParmType *TypeParm
2869    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2870
2871  if (TypeParm)
2872    return QualType(TypeParm, 0);
2873
2874  if (TTPDecl) {
2875    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
2876    TypeParm = new (*this, TypeAlignment) TemplateTypeParmType(TTPDecl, Canon);
2877
2878    TemplateTypeParmType *TypeCheck
2879      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
2880    assert(!TypeCheck && "Template type parameter canonical type broken");
2881    (void)TypeCheck;
2882  } else
2883    TypeParm = new (*this, TypeAlignment)
2884      TemplateTypeParmType(Depth, Index, ParameterPack);
2885
2886  Types.push_back(TypeParm);
2887  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
2888
2889  return QualType(TypeParm, 0);
2890}
2891
2892TypeSourceInfo *
2893ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
2894                                              SourceLocation NameLoc,
2895                                        const TemplateArgumentListInfo &Args,
2896                                              QualType Underlying) const {
2897  assert(!Name.getAsDependentTemplateName() &&
2898         "No dependent template names here!");
2899  QualType TST = getTemplateSpecializationType(Name, Args, Underlying);
2900
2901  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
2902  TemplateSpecializationTypeLoc TL
2903    = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
2904  TL.setTemplateKeywordLoc(SourceLocation());
2905  TL.setTemplateNameLoc(NameLoc);
2906  TL.setLAngleLoc(Args.getLAngleLoc());
2907  TL.setRAngleLoc(Args.getRAngleLoc());
2908  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
2909    TL.setArgLocInfo(i, Args[i].getLocInfo());
2910  return DI;
2911}
2912
2913QualType
2914ASTContext::getTemplateSpecializationType(TemplateName Template,
2915                                          const TemplateArgumentListInfo &Args,
2916                                          QualType Underlying) const {
2917  assert(!Template.getAsDependentTemplateName() &&
2918         "No dependent template names here!");
2919
2920  unsigned NumArgs = Args.size();
2921
2922  SmallVector<TemplateArgument, 4> ArgVec;
2923  ArgVec.reserve(NumArgs);
2924  for (unsigned i = 0; i != NumArgs; ++i)
2925    ArgVec.push_back(Args[i].getArgument());
2926
2927  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
2928                                       Underlying);
2929}
2930
2931#ifndef NDEBUG
2932static bool hasAnyPackExpansions(const TemplateArgument *Args,
2933                                 unsigned NumArgs) {
2934  for (unsigned I = 0; I != NumArgs; ++I)
2935    if (Args[I].isPackExpansion())
2936      return true;
2937
2938  return true;
2939}
2940#endif
2941
2942QualType
2943ASTContext::getTemplateSpecializationType(TemplateName Template,
2944                                          const TemplateArgument *Args,
2945                                          unsigned NumArgs,
2946                                          QualType Underlying) const {
2947  assert(!Template.getAsDependentTemplateName() &&
2948         "No dependent template names here!");
2949  // Look through qualified template names.
2950  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2951    Template = TemplateName(QTN->getTemplateDecl());
2952
2953  bool IsTypeAlias =
2954    Template.getAsTemplateDecl() &&
2955    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
2956  QualType CanonType;
2957  if (!Underlying.isNull())
2958    CanonType = getCanonicalType(Underlying);
2959  else {
2960    // We can get here with an alias template when the specialization contains
2961    // a pack expansion that does not match up with a parameter pack.
2962    assert((!IsTypeAlias || hasAnyPackExpansions(Args, NumArgs)) &&
2963           "Caller must compute aliased type");
2964    IsTypeAlias = false;
2965    CanonType = getCanonicalTemplateSpecializationType(Template, Args,
2966                                                       NumArgs);
2967  }
2968
2969  // Allocate the (non-canonical) template specialization type, but don't
2970  // try to unique it: these types typically have location information that
2971  // we don't unique and don't want to lose.
2972  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
2973                       sizeof(TemplateArgument) * NumArgs +
2974                       (IsTypeAlias? sizeof(QualType) : 0),
2975                       TypeAlignment);
2976  TemplateSpecializationType *Spec
2977    = new (Mem) TemplateSpecializationType(Template, Args, NumArgs, CanonType,
2978                                         IsTypeAlias ? Underlying : QualType());
2979
2980  Types.push_back(Spec);
2981  return QualType(Spec, 0);
2982}
2983
2984QualType
2985ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
2986                                                   const TemplateArgument *Args,
2987                                                   unsigned NumArgs) const {
2988  assert(!Template.getAsDependentTemplateName() &&
2989         "No dependent template names here!");
2990
2991  // Look through qualified template names.
2992  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
2993    Template = TemplateName(QTN->getTemplateDecl());
2994
2995  // Build the canonical template specialization type.
2996  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
2997  SmallVector<TemplateArgument, 4> CanonArgs;
2998  CanonArgs.reserve(NumArgs);
2999  for (unsigned I = 0; I != NumArgs; ++I)
3000    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
3001
3002  // Determine whether this canonical template specialization type already
3003  // exists.
3004  llvm::FoldingSetNodeID ID;
3005  TemplateSpecializationType::Profile(ID, CanonTemplate,
3006                                      CanonArgs.data(), NumArgs, *this);
3007
3008  void *InsertPos = 0;
3009  TemplateSpecializationType *Spec
3010    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3011
3012  if (!Spec) {
3013    // Allocate a new canonical template specialization type.
3014    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
3015                          sizeof(TemplateArgument) * NumArgs),
3016                         TypeAlignment);
3017    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
3018                                                CanonArgs.data(), NumArgs,
3019                                                QualType(), QualType());
3020    Types.push_back(Spec);
3021    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
3022  }
3023
3024  assert(Spec->isDependentType() &&
3025         "Non-dependent template-id type must have a canonical type");
3026  return QualType(Spec, 0);
3027}
3028
3029QualType
3030ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
3031                              NestedNameSpecifier *NNS,
3032                              QualType NamedType) const {
3033  llvm::FoldingSetNodeID ID;
3034  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
3035
3036  void *InsertPos = 0;
3037  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
3038  if (T)
3039    return QualType(T, 0);
3040
3041  QualType Canon = NamedType;
3042  if (!Canon.isCanonical()) {
3043    Canon = getCanonicalType(NamedType);
3044    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
3045    assert(!CheckT && "Elaborated canonical type broken");
3046    (void)CheckT;
3047  }
3048
3049  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
3050  Types.push_back(T);
3051  ElaboratedTypes.InsertNode(T, InsertPos);
3052  return QualType(T, 0);
3053}
3054
3055QualType
3056ASTContext::getParenType(QualType InnerType) const {
3057  llvm::FoldingSetNodeID ID;
3058  ParenType::Profile(ID, InnerType);
3059
3060  void *InsertPos = 0;
3061  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
3062  if (T)
3063    return QualType(T, 0);
3064
3065  QualType Canon = InnerType;
3066  if (!Canon.isCanonical()) {
3067    Canon = getCanonicalType(InnerType);
3068    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
3069    assert(!CheckT && "Paren canonical type broken");
3070    (void)CheckT;
3071  }
3072
3073  T = new (*this) ParenType(InnerType, Canon);
3074  Types.push_back(T);
3075  ParenTypes.InsertNode(T, InsertPos);
3076  return QualType(T, 0);
3077}
3078
3079QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
3080                                          NestedNameSpecifier *NNS,
3081                                          const IdentifierInfo *Name,
3082                                          QualType Canon) const {
3083  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
3084
3085  if (Canon.isNull()) {
3086    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
3087    ElaboratedTypeKeyword CanonKeyword = Keyword;
3088    if (Keyword == ETK_None)
3089      CanonKeyword = ETK_Typename;
3090
3091    if (CanonNNS != NNS || CanonKeyword != Keyword)
3092      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
3093  }
3094
3095  llvm::FoldingSetNodeID ID;
3096  DependentNameType::Profile(ID, Keyword, NNS, Name);
3097
3098  void *InsertPos = 0;
3099  DependentNameType *T
3100    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
3101  if (T)
3102    return QualType(T, 0);
3103
3104  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
3105  Types.push_back(T);
3106  DependentNameTypes.InsertNode(T, InsertPos);
3107  return QualType(T, 0);
3108}
3109
3110QualType
3111ASTContext::getDependentTemplateSpecializationType(
3112                                 ElaboratedTypeKeyword Keyword,
3113                                 NestedNameSpecifier *NNS,
3114                                 const IdentifierInfo *Name,
3115                                 const TemplateArgumentListInfo &Args) const {
3116  // TODO: avoid this copy
3117  SmallVector<TemplateArgument, 16> ArgCopy;
3118  for (unsigned I = 0, E = Args.size(); I != E; ++I)
3119    ArgCopy.push_back(Args[I].getArgument());
3120  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
3121                                                ArgCopy.size(),
3122                                                ArgCopy.data());
3123}
3124
3125QualType
3126ASTContext::getDependentTemplateSpecializationType(
3127                                 ElaboratedTypeKeyword Keyword,
3128                                 NestedNameSpecifier *NNS,
3129                                 const IdentifierInfo *Name,
3130                                 unsigned NumArgs,
3131                                 const TemplateArgument *Args) const {
3132  assert((!NNS || NNS->isDependent()) &&
3133         "nested-name-specifier must be dependent");
3134
3135  llvm::FoldingSetNodeID ID;
3136  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
3137                                               Name, NumArgs, Args);
3138
3139  void *InsertPos = 0;
3140  DependentTemplateSpecializationType *T
3141    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3142  if (T)
3143    return QualType(T, 0);
3144
3145  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
3146
3147  ElaboratedTypeKeyword CanonKeyword = Keyword;
3148  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
3149
3150  bool AnyNonCanonArgs = false;
3151  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
3152  for (unsigned I = 0; I != NumArgs; ++I) {
3153    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
3154    if (!CanonArgs[I].structurallyEquals(Args[I]))
3155      AnyNonCanonArgs = true;
3156  }
3157
3158  QualType Canon;
3159  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
3160    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
3161                                                   Name, NumArgs,
3162                                                   CanonArgs.data());
3163
3164    // Find the insert position again.
3165    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3166  }
3167
3168  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
3169                        sizeof(TemplateArgument) * NumArgs),
3170                       TypeAlignment);
3171  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
3172                                                    Name, NumArgs, Args, Canon);
3173  Types.push_back(T);
3174  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
3175  return QualType(T, 0);
3176}
3177
3178QualType ASTContext::getPackExpansionType(QualType Pattern,
3179                                      llvm::Optional<unsigned> NumExpansions) {
3180  llvm::FoldingSetNodeID ID;
3181  PackExpansionType::Profile(ID, Pattern, NumExpansions);
3182
3183  assert(Pattern->containsUnexpandedParameterPack() &&
3184         "Pack expansions must expand one or more parameter packs");
3185  void *InsertPos = 0;
3186  PackExpansionType *T
3187    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3188  if (T)
3189    return QualType(T, 0);
3190
3191  QualType Canon;
3192  if (!Pattern.isCanonical()) {
3193    Canon = getCanonicalType(Pattern);
3194    // The canonical type might not contain an unexpanded parameter pack, if it
3195    // contains an alias template specialization which ignores one of its
3196    // parameters.
3197    if (Canon->containsUnexpandedParameterPack()) {
3198      Canon = getPackExpansionType(getCanonicalType(Pattern), NumExpansions);
3199
3200      // Find the insert position again, in case we inserted an element into
3201      // PackExpansionTypes and invalidated our insert position.
3202      PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3203    }
3204  }
3205
3206  T = new (*this) PackExpansionType(Pattern, Canon, NumExpansions);
3207  Types.push_back(T);
3208  PackExpansionTypes.InsertNode(T, InsertPos);
3209  return QualType(T, 0);
3210}
3211
3212/// CmpProtocolNames - Comparison predicate for sorting protocols
3213/// alphabetically.
3214static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
3215                            const ObjCProtocolDecl *RHS) {
3216  return LHS->getDeclName() < RHS->getDeclName();
3217}
3218
3219static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
3220                                unsigned NumProtocols) {
3221  if (NumProtocols == 0) return true;
3222
3223  if (Protocols[0]->getCanonicalDecl() != Protocols[0])
3224    return false;
3225
3226  for (unsigned i = 1; i != NumProtocols; ++i)
3227    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]) ||
3228        Protocols[i]->getCanonicalDecl() != Protocols[i])
3229      return false;
3230  return true;
3231}
3232
3233static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
3234                                   unsigned &NumProtocols) {
3235  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
3236
3237  // Sort protocols, keyed by name.
3238  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
3239
3240  // Canonicalize.
3241  for (unsigned I = 0, N = NumProtocols; I != N; ++I)
3242    Protocols[I] = Protocols[I]->getCanonicalDecl();
3243
3244  // Remove duplicates.
3245  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
3246  NumProtocols = ProtocolsEnd-Protocols;
3247}
3248
3249QualType ASTContext::getObjCObjectType(QualType BaseType,
3250                                       ObjCProtocolDecl * const *Protocols,
3251                                       unsigned NumProtocols) const {
3252  // If the base type is an interface and there aren't any protocols
3253  // to add, then the interface type will do just fine.
3254  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
3255    return BaseType;
3256
3257  // Look in the folding set for an existing type.
3258  llvm::FoldingSetNodeID ID;
3259  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
3260  void *InsertPos = 0;
3261  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
3262    return QualType(QT, 0);
3263
3264  // Build the canonical type, which has the canonical base type and
3265  // a sorted-and-uniqued list of protocols.
3266  QualType Canonical;
3267  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
3268  if (!ProtocolsSorted || !BaseType.isCanonical()) {
3269    if (!ProtocolsSorted) {
3270      SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
3271                                                     Protocols + NumProtocols);
3272      unsigned UniqueCount = NumProtocols;
3273
3274      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
3275      Canonical = getObjCObjectType(getCanonicalType(BaseType),
3276                                    &Sorted[0], UniqueCount);
3277    } else {
3278      Canonical = getObjCObjectType(getCanonicalType(BaseType),
3279                                    Protocols, NumProtocols);
3280    }
3281
3282    // Regenerate InsertPos.
3283    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
3284  }
3285
3286  unsigned Size = sizeof(ObjCObjectTypeImpl);
3287  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
3288  void *Mem = Allocate(Size, TypeAlignment);
3289  ObjCObjectTypeImpl *T =
3290    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
3291
3292  Types.push_back(T);
3293  ObjCObjectTypes.InsertNode(T, InsertPos);
3294  return QualType(T, 0);
3295}
3296
3297/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
3298/// the given object type.
3299QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
3300  llvm::FoldingSetNodeID ID;
3301  ObjCObjectPointerType::Profile(ID, ObjectT);
3302
3303  void *InsertPos = 0;
3304  if (ObjCObjectPointerType *QT =
3305              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
3306    return QualType(QT, 0);
3307
3308  // Find the canonical object type.
3309  QualType Canonical;
3310  if (!ObjectT.isCanonical()) {
3311    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
3312
3313    // Regenerate InsertPos.
3314    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
3315  }
3316
3317  // No match.
3318  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
3319  ObjCObjectPointerType *QType =
3320    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
3321
3322  Types.push_back(QType);
3323  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
3324  return QualType(QType, 0);
3325}
3326
3327/// getObjCInterfaceType - Return the unique reference to the type for the
3328/// specified ObjC interface decl. The list of protocols is optional.
3329QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
3330                                          ObjCInterfaceDecl *PrevDecl) const {
3331  if (Decl->TypeForDecl)
3332    return QualType(Decl->TypeForDecl, 0);
3333
3334  if (PrevDecl) {
3335    assert(PrevDecl->TypeForDecl && "previous decl has no TypeForDecl");
3336    Decl->TypeForDecl = PrevDecl->TypeForDecl;
3337    return QualType(PrevDecl->TypeForDecl, 0);
3338  }
3339
3340  // Prefer the definition, if there is one.
3341  if (const ObjCInterfaceDecl *Def = Decl->getDefinition())
3342    Decl = Def;
3343
3344  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
3345  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
3346  Decl->TypeForDecl = T;
3347  Types.push_back(T);
3348  return QualType(T, 0);
3349}
3350
3351/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
3352/// TypeOfExprType AST's (since expression's are never shared). For example,
3353/// multiple declarations that refer to "typeof(x)" all contain different
3354/// DeclRefExpr's. This doesn't effect the type checker, since it operates
3355/// on canonical type's (which are always unique).
3356QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
3357  TypeOfExprType *toe;
3358  if (tofExpr->isTypeDependent()) {
3359    llvm::FoldingSetNodeID ID;
3360    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
3361
3362    void *InsertPos = 0;
3363    DependentTypeOfExprType *Canon
3364      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
3365    if (Canon) {
3366      // We already have a "canonical" version of an identical, dependent
3367      // typeof(expr) type. Use that as our canonical type.
3368      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
3369                                          QualType((TypeOfExprType*)Canon, 0));
3370    } else {
3371      // Build a new, canonical typeof(expr) type.
3372      Canon
3373        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
3374      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
3375      toe = Canon;
3376    }
3377  } else {
3378    QualType Canonical = getCanonicalType(tofExpr->getType());
3379    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
3380  }
3381  Types.push_back(toe);
3382  return QualType(toe, 0);
3383}
3384
3385/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
3386/// TypeOfType AST's. The only motivation to unique these nodes would be
3387/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
3388/// an issue. This doesn't effect the type checker, since it operates
3389/// on canonical type's (which are always unique).
3390QualType ASTContext::getTypeOfType(QualType tofType) const {
3391  QualType Canonical = getCanonicalType(tofType);
3392  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
3393  Types.push_back(tot);
3394  return QualType(tot, 0);
3395}
3396
3397
3398/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
3399/// DecltypeType AST's. The only motivation to unique these nodes would be
3400/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
3401/// an issue. This doesn't effect the type checker, since it operates
3402/// on canonical types (which are always unique).
3403QualType ASTContext::getDecltypeType(Expr *e, QualType UnderlyingType) const {
3404  DecltypeType *dt;
3405
3406  // C++0x [temp.type]p2:
3407  //   If an expression e involves a template parameter, decltype(e) denotes a
3408  //   unique dependent type. Two such decltype-specifiers refer to the same
3409  //   type only if their expressions are equivalent (14.5.6.1).
3410  if (e->isInstantiationDependent()) {
3411    llvm::FoldingSetNodeID ID;
3412    DependentDecltypeType::Profile(ID, *this, e);
3413
3414    void *InsertPos = 0;
3415    DependentDecltypeType *Canon
3416      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
3417    if (Canon) {
3418      // We already have a "canonical" version of an equivalent, dependent
3419      // decltype type. Use that as our canonical type.
3420      dt = new (*this, TypeAlignment) DecltypeType(e, UnderlyingType,
3421                                       QualType((DecltypeType*)Canon, 0));
3422    } else {
3423      // Build a new, canonical typeof(expr) type.
3424      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
3425      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
3426      dt = Canon;
3427    }
3428  } else {
3429    dt = new (*this, TypeAlignment) DecltypeType(e, UnderlyingType,
3430                                      getCanonicalType(UnderlyingType));
3431  }
3432  Types.push_back(dt);
3433  return QualType(dt, 0);
3434}
3435
3436/// getUnaryTransformationType - We don't unique these, since the memory
3437/// savings are minimal and these are rare.
3438QualType ASTContext::getUnaryTransformType(QualType BaseType,
3439                                           QualType UnderlyingType,
3440                                           UnaryTransformType::UTTKind Kind)
3441    const {
3442  UnaryTransformType *Ty =
3443    new (*this, TypeAlignment) UnaryTransformType (BaseType, UnderlyingType,
3444                                                   Kind,
3445                                 UnderlyingType->isDependentType() ?
3446                                 QualType() : getCanonicalType(UnderlyingType));
3447  Types.push_back(Ty);
3448  return QualType(Ty, 0);
3449}
3450
3451/// getAutoType - We only unique auto types after they've been deduced.
3452QualType ASTContext::getAutoType(QualType DeducedType) const {
3453  void *InsertPos = 0;
3454  if (!DeducedType.isNull()) {
3455    // Look in the folding set for an existing type.
3456    llvm::FoldingSetNodeID ID;
3457    AutoType::Profile(ID, DeducedType);
3458    if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
3459      return QualType(AT, 0);
3460  }
3461
3462  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType);
3463  Types.push_back(AT);
3464  if (InsertPos)
3465    AutoTypes.InsertNode(AT, InsertPos);
3466  return QualType(AT, 0);
3467}
3468
3469/// getAtomicType - Return the uniqued reference to the atomic type for
3470/// the given value type.
3471QualType ASTContext::getAtomicType(QualType T) const {
3472  // Unique pointers, to guarantee there is only one pointer of a particular
3473  // structure.
3474  llvm::FoldingSetNodeID ID;
3475  AtomicType::Profile(ID, T);
3476
3477  void *InsertPos = 0;
3478  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
3479    return QualType(AT, 0);
3480
3481  // If the atomic value type isn't canonical, this won't be a canonical type
3482  // either, so fill in the canonical type field.
3483  QualType Canonical;
3484  if (!T.isCanonical()) {
3485    Canonical = getAtomicType(getCanonicalType(T));
3486
3487    // Get the new insert position for the node we care about.
3488    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
3489    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
3490  }
3491  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
3492  Types.push_back(New);
3493  AtomicTypes.InsertNode(New, InsertPos);
3494  return QualType(New, 0);
3495}
3496
3497/// getAutoDeductType - Get type pattern for deducing against 'auto'.
3498QualType ASTContext::getAutoDeductType() const {
3499  if (AutoDeductTy.isNull())
3500    AutoDeductTy = getAutoType(QualType());
3501  assert(!AutoDeductTy.isNull() && "can't build 'auto' pattern");
3502  return AutoDeductTy;
3503}
3504
3505/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
3506QualType ASTContext::getAutoRRefDeductType() const {
3507  if (AutoRRefDeductTy.isNull())
3508    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
3509  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
3510  return AutoRRefDeductTy;
3511}
3512
3513/// getTagDeclType - Return the unique reference to the type for the
3514/// specified TagDecl (struct/union/class/enum) decl.
3515QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
3516  assert (Decl);
3517  // FIXME: What is the design on getTagDeclType when it requires casting
3518  // away const?  mutable?
3519  return getTypeDeclType(const_cast<TagDecl*>(Decl));
3520}
3521
3522/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
3523/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
3524/// needs to agree with the definition in <stddef.h>.
3525CanQualType ASTContext::getSizeType() const {
3526  return getFromTargetType(Target->getSizeType());
3527}
3528
3529/// getIntMaxType - Return the unique type for "intmax_t" (C99 7.18.1.5).
3530CanQualType ASTContext::getIntMaxType() const {
3531  return getFromTargetType(Target->getIntMaxType());
3532}
3533
3534/// getUIntMaxType - Return the unique type for "uintmax_t" (C99 7.18.1.5).
3535CanQualType ASTContext::getUIntMaxType() const {
3536  return getFromTargetType(Target->getUIntMaxType());
3537}
3538
3539/// getSignedWCharType - Return the type of "signed wchar_t".
3540/// Used when in C++, as a GCC extension.
3541QualType ASTContext::getSignedWCharType() const {
3542  // FIXME: derive from "Target" ?
3543  return WCharTy;
3544}
3545
3546/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
3547/// Used when in C++, as a GCC extension.
3548QualType ASTContext::getUnsignedWCharType() const {
3549  // FIXME: derive from "Target" ?
3550  return UnsignedIntTy;
3551}
3552
3553/// getPointerDiffType - Return the unique type for "ptrdiff_t" (C99 7.17)
3554/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
3555QualType ASTContext::getPointerDiffType() const {
3556  return getFromTargetType(Target->getPtrDiffType(0));
3557}
3558
3559/// \brief Return the unique type for "pid_t" defined in
3560/// <sys/types.h>. We need this to compute the correct type for vfork().
3561QualType ASTContext::getProcessIDType() const {
3562  return getFromTargetType(Target->getProcessIDType());
3563}
3564
3565//===----------------------------------------------------------------------===//
3566//                              Type Operators
3567//===----------------------------------------------------------------------===//
3568
3569CanQualType ASTContext::getCanonicalParamType(QualType T) const {
3570  // Push qualifiers into arrays, and then discard any remaining
3571  // qualifiers.
3572  T = getCanonicalType(T);
3573  T = getVariableArrayDecayedType(T);
3574  const Type *Ty = T.getTypePtr();
3575  QualType Result;
3576  if (isa<ArrayType>(Ty)) {
3577    Result = getArrayDecayedType(QualType(Ty,0));
3578  } else if (isa<FunctionType>(Ty)) {
3579    Result = getPointerType(QualType(Ty, 0));
3580  } else {
3581    Result = QualType(Ty, 0);
3582  }
3583
3584  return CanQualType::CreateUnsafe(Result);
3585}
3586
3587QualType ASTContext::getUnqualifiedArrayType(QualType type,
3588                                             Qualifiers &quals) {
3589  SplitQualType splitType = type.getSplitUnqualifiedType();
3590
3591  // FIXME: getSplitUnqualifiedType() actually walks all the way to
3592  // the unqualified desugared type and then drops it on the floor.
3593  // We then have to strip that sugar back off with
3594  // getUnqualifiedDesugaredType(), which is silly.
3595  const ArrayType *AT =
3596    dyn_cast<ArrayType>(splitType.Ty->getUnqualifiedDesugaredType());
3597
3598  // If we don't have an array, just use the results in splitType.
3599  if (!AT) {
3600    quals = splitType.Quals;
3601    return QualType(splitType.Ty, 0);
3602  }
3603
3604  // Otherwise, recurse on the array's element type.
3605  QualType elementType = AT->getElementType();
3606  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
3607
3608  // If that didn't change the element type, AT has no qualifiers, so we
3609  // can just use the results in splitType.
3610  if (elementType == unqualElementType) {
3611    assert(quals.empty()); // from the recursive call
3612    quals = splitType.Quals;
3613    return QualType(splitType.Ty, 0);
3614  }
3615
3616  // Otherwise, add in the qualifiers from the outermost type, then
3617  // build the type back up.
3618  quals.addConsistentQualifiers(splitType.Quals);
3619
3620  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
3621    return getConstantArrayType(unqualElementType, CAT->getSize(),
3622                                CAT->getSizeModifier(), 0);
3623  }
3624
3625  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
3626    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
3627  }
3628
3629  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
3630    return getVariableArrayType(unqualElementType,
3631                                VAT->getSizeExpr(),
3632                                VAT->getSizeModifier(),
3633                                VAT->getIndexTypeCVRQualifiers(),
3634                                VAT->getBracketsRange());
3635  }
3636
3637  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
3638  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
3639                                    DSAT->getSizeModifier(), 0,
3640                                    SourceRange());
3641}
3642
3643/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
3644/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
3645/// they point to and return true. If T1 and T2 aren't pointer types
3646/// or pointer-to-member types, or if they are not similar at this
3647/// level, returns false and leaves T1 and T2 unchanged. Top-level
3648/// qualifiers on T1 and T2 are ignored. This function will typically
3649/// be called in a loop that successively "unwraps" pointer and
3650/// pointer-to-member types to compare them at each level.
3651bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
3652  const PointerType *T1PtrType = T1->getAs<PointerType>(),
3653                    *T2PtrType = T2->getAs<PointerType>();
3654  if (T1PtrType && T2PtrType) {
3655    T1 = T1PtrType->getPointeeType();
3656    T2 = T2PtrType->getPointeeType();
3657    return true;
3658  }
3659
3660  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
3661                          *T2MPType = T2->getAs<MemberPointerType>();
3662  if (T1MPType && T2MPType &&
3663      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
3664                             QualType(T2MPType->getClass(), 0))) {
3665    T1 = T1MPType->getPointeeType();
3666    T2 = T2MPType->getPointeeType();
3667    return true;
3668  }
3669
3670  if (getLangOpts().ObjC1) {
3671    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
3672                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
3673    if (T1OPType && T2OPType) {
3674      T1 = T1OPType->getPointeeType();
3675      T2 = T2OPType->getPointeeType();
3676      return true;
3677    }
3678  }
3679
3680  // FIXME: Block pointers, too?
3681
3682  return false;
3683}
3684
3685DeclarationNameInfo
3686ASTContext::getNameForTemplate(TemplateName Name,
3687                               SourceLocation NameLoc) const {
3688  switch (Name.getKind()) {
3689  case TemplateName::QualifiedTemplate:
3690  case TemplateName::Template:
3691    // DNInfo work in progress: CHECKME: what about DNLoc?
3692    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
3693                               NameLoc);
3694
3695  case TemplateName::OverloadedTemplate: {
3696    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
3697    // DNInfo work in progress: CHECKME: what about DNLoc?
3698    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
3699  }
3700
3701  case TemplateName::DependentTemplate: {
3702    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3703    DeclarationName DName;
3704    if (DTN->isIdentifier()) {
3705      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
3706      return DeclarationNameInfo(DName, NameLoc);
3707    } else {
3708      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
3709      // DNInfo work in progress: FIXME: source locations?
3710      DeclarationNameLoc DNLoc;
3711      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
3712      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
3713      return DeclarationNameInfo(DName, NameLoc, DNLoc);
3714    }
3715  }
3716
3717  case TemplateName::SubstTemplateTemplateParm: {
3718    SubstTemplateTemplateParmStorage *subst
3719      = Name.getAsSubstTemplateTemplateParm();
3720    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
3721                               NameLoc);
3722  }
3723
3724  case TemplateName::SubstTemplateTemplateParmPack: {
3725    SubstTemplateTemplateParmPackStorage *subst
3726      = Name.getAsSubstTemplateTemplateParmPack();
3727    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
3728                               NameLoc);
3729  }
3730  }
3731
3732  llvm_unreachable("bad template name kind!");
3733}
3734
3735TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
3736  switch (Name.getKind()) {
3737  case TemplateName::QualifiedTemplate:
3738  case TemplateName::Template: {
3739    TemplateDecl *Template = Name.getAsTemplateDecl();
3740    if (TemplateTemplateParmDecl *TTP
3741          = dyn_cast<TemplateTemplateParmDecl>(Template))
3742      Template = getCanonicalTemplateTemplateParmDecl(TTP);
3743
3744    // The canonical template name is the canonical template declaration.
3745    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
3746  }
3747
3748  case TemplateName::OverloadedTemplate:
3749    llvm_unreachable("cannot canonicalize overloaded template");
3750
3751  case TemplateName::DependentTemplate: {
3752    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3753    assert(DTN && "Non-dependent template names must refer to template decls.");
3754    return DTN->CanonicalTemplateName;
3755  }
3756
3757  case TemplateName::SubstTemplateTemplateParm: {
3758    SubstTemplateTemplateParmStorage *subst
3759      = Name.getAsSubstTemplateTemplateParm();
3760    return getCanonicalTemplateName(subst->getReplacement());
3761  }
3762
3763  case TemplateName::SubstTemplateTemplateParmPack: {
3764    SubstTemplateTemplateParmPackStorage *subst
3765                                  = Name.getAsSubstTemplateTemplateParmPack();
3766    TemplateTemplateParmDecl *canonParameter
3767      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
3768    TemplateArgument canonArgPack
3769      = getCanonicalTemplateArgument(subst->getArgumentPack());
3770    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
3771  }
3772  }
3773
3774  llvm_unreachable("bad template name!");
3775}
3776
3777bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
3778  X = getCanonicalTemplateName(X);
3779  Y = getCanonicalTemplateName(Y);
3780  return X.getAsVoidPointer() == Y.getAsVoidPointer();
3781}
3782
3783TemplateArgument
3784ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
3785  switch (Arg.getKind()) {
3786    case TemplateArgument::Null:
3787      return Arg;
3788
3789    case TemplateArgument::Expression:
3790      return Arg;
3791
3792    case TemplateArgument::Declaration: {
3793      ValueDecl *D = cast<ValueDecl>(Arg.getAsDecl()->getCanonicalDecl());
3794      return TemplateArgument(D, Arg.isDeclForReferenceParam());
3795    }
3796
3797    case TemplateArgument::NullPtr:
3798      return TemplateArgument(getCanonicalType(Arg.getNullPtrType()),
3799                              /*isNullPtr*/true);
3800
3801    case TemplateArgument::Template:
3802      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
3803
3804    case TemplateArgument::TemplateExpansion:
3805      return TemplateArgument(getCanonicalTemplateName(
3806                                         Arg.getAsTemplateOrTemplatePattern()),
3807                              Arg.getNumTemplateExpansions());
3808
3809    case TemplateArgument::Integral:
3810      return TemplateArgument(Arg, getCanonicalType(Arg.getIntegralType()));
3811
3812    case TemplateArgument::Type:
3813      return TemplateArgument(getCanonicalType(Arg.getAsType()));
3814
3815    case TemplateArgument::Pack: {
3816      if (Arg.pack_size() == 0)
3817        return Arg;
3818
3819      TemplateArgument *CanonArgs
3820        = new (*this) TemplateArgument[Arg.pack_size()];
3821      unsigned Idx = 0;
3822      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
3823                                        AEnd = Arg.pack_end();
3824           A != AEnd; (void)++A, ++Idx)
3825        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
3826
3827      return TemplateArgument(CanonArgs, Arg.pack_size());
3828    }
3829  }
3830
3831  // Silence GCC warning
3832  llvm_unreachable("Unhandled template argument kind");
3833}
3834
3835NestedNameSpecifier *
3836ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
3837  if (!NNS)
3838    return 0;
3839
3840  switch (NNS->getKind()) {
3841  case NestedNameSpecifier::Identifier:
3842    // Canonicalize the prefix but keep the identifier the same.
3843    return NestedNameSpecifier::Create(*this,
3844                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
3845                                       NNS->getAsIdentifier());
3846
3847  case NestedNameSpecifier::Namespace:
3848    // A namespace is canonical; build a nested-name-specifier with
3849    // this namespace and no prefix.
3850    return NestedNameSpecifier::Create(*this, 0,
3851                                 NNS->getAsNamespace()->getOriginalNamespace());
3852
3853  case NestedNameSpecifier::NamespaceAlias:
3854    // A namespace is canonical; build a nested-name-specifier with
3855    // this namespace and no prefix.
3856    return NestedNameSpecifier::Create(*this, 0,
3857                                    NNS->getAsNamespaceAlias()->getNamespace()
3858                                                      ->getOriginalNamespace());
3859
3860  case NestedNameSpecifier::TypeSpec:
3861  case NestedNameSpecifier::TypeSpecWithTemplate: {
3862    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
3863
3864    // If we have some kind of dependent-named type (e.g., "typename T::type"),
3865    // break it apart into its prefix and identifier, then reconsititute those
3866    // as the canonical nested-name-specifier. This is required to canonicalize
3867    // a dependent nested-name-specifier involving typedefs of dependent-name
3868    // types, e.g.,
3869    //   typedef typename T::type T1;
3870    //   typedef typename T1::type T2;
3871    if (const DependentNameType *DNT = T->getAs<DependentNameType>())
3872      return NestedNameSpecifier::Create(*this, DNT->getQualifier(),
3873                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
3874
3875    // Otherwise, just canonicalize the type, and force it to be a TypeSpec.
3876    // FIXME: Why are TypeSpec and TypeSpecWithTemplate distinct in the
3877    // first place?
3878    return NestedNameSpecifier::Create(*this, 0, false,
3879                                       const_cast<Type*>(T.getTypePtr()));
3880  }
3881
3882  case NestedNameSpecifier::Global:
3883    // The global specifier is canonical and unique.
3884    return NNS;
3885  }
3886
3887  llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
3888}
3889
3890
3891const ArrayType *ASTContext::getAsArrayType(QualType T) const {
3892  // Handle the non-qualified case efficiently.
3893  if (!T.hasLocalQualifiers()) {
3894    // Handle the common positive case fast.
3895    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
3896      return AT;
3897  }
3898
3899  // Handle the common negative case fast.
3900  if (!isa<ArrayType>(T.getCanonicalType()))
3901    return 0;
3902
3903  // Apply any qualifiers from the array type to the element type.  This
3904  // implements C99 6.7.3p8: "If the specification of an array type includes
3905  // any type qualifiers, the element type is so qualified, not the array type."
3906
3907  // If we get here, we either have type qualifiers on the type, or we have
3908  // sugar such as a typedef in the way.  If we have type qualifiers on the type
3909  // we must propagate them down into the element type.
3910
3911  SplitQualType split = T.getSplitDesugaredType();
3912  Qualifiers qs = split.Quals;
3913
3914  // If we have a simple case, just return now.
3915  const ArrayType *ATy = dyn_cast<ArrayType>(split.Ty);
3916  if (ATy == 0 || qs.empty())
3917    return ATy;
3918
3919  // Otherwise, we have an array and we have qualifiers on it.  Push the
3920  // qualifiers into the array element type and return a new array type.
3921  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
3922
3923  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
3924    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
3925                                                CAT->getSizeModifier(),
3926                                           CAT->getIndexTypeCVRQualifiers()));
3927  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
3928    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
3929                                                  IAT->getSizeModifier(),
3930                                           IAT->getIndexTypeCVRQualifiers()));
3931
3932  if (const DependentSizedArrayType *DSAT
3933        = dyn_cast<DependentSizedArrayType>(ATy))
3934    return cast<ArrayType>(
3935                     getDependentSizedArrayType(NewEltTy,
3936                                                DSAT->getSizeExpr(),
3937                                                DSAT->getSizeModifier(),
3938                                              DSAT->getIndexTypeCVRQualifiers(),
3939                                                DSAT->getBracketsRange()));
3940
3941  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
3942  return cast<ArrayType>(getVariableArrayType(NewEltTy,
3943                                              VAT->getSizeExpr(),
3944                                              VAT->getSizeModifier(),
3945                                              VAT->getIndexTypeCVRQualifiers(),
3946                                              VAT->getBracketsRange()));
3947}
3948
3949QualType ASTContext::getAdjustedParameterType(QualType T) const {
3950  // C99 6.7.5.3p7:
3951  //   A declaration of a parameter as "array of type" shall be
3952  //   adjusted to "qualified pointer to type", where the type
3953  //   qualifiers (if any) are those specified within the [ and ] of
3954  //   the array type derivation.
3955  if (T->isArrayType())
3956    return getArrayDecayedType(T);
3957
3958  // C99 6.7.5.3p8:
3959  //   A declaration of a parameter as "function returning type"
3960  //   shall be adjusted to "pointer to function returning type", as
3961  //   in 6.3.2.1.
3962  if (T->isFunctionType())
3963    return getPointerType(T);
3964
3965  return T;
3966}
3967
3968QualType ASTContext::getSignatureParameterType(QualType T) const {
3969  T = getVariableArrayDecayedType(T);
3970  T = getAdjustedParameterType(T);
3971  return T.getUnqualifiedType();
3972}
3973
3974/// getArrayDecayedType - Return the properly qualified result of decaying the
3975/// specified array type to a pointer.  This operation is non-trivial when
3976/// handling typedefs etc.  The canonical type of "T" must be an array type,
3977/// this returns a pointer to a properly qualified element of the array.
3978///
3979/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
3980QualType ASTContext::getArrayDecayedType(QualType Ty) const {
3981  // Get the element type with 'getAsArrayType' so that we don't lose any
3982  // typedefs in the element type of the array.  This also handles propagation
3983  // of type qualifiers from the array type into the element type if present
3984  // (C99 6.7.3p8).
3985  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
3986  assert(PrettyArrayType && "Not an array type!");
3987
3988  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
3989
3990  // int x[restrict 4] ->  int *restrict
3991  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
3992}
3993
3994QualType ASTContext::getBaseElementType(const ArrayType *array) const {
3995  return getBaseElementType(array->getElementType());
3996}
3997
3998QualType ASTContext::getBaseElementType(QualType type) const {
3999  Qualifiers qs;
4000  while (true) {
4001    SplitQualType split = type.getSplitDesugaredType();
4002    const ArrayType *array = split.Ty->getAsArrayTypeUnsafe();
4003    if (!array) break;
4004
4005    type = array->getElementType();
4006    qs.addConsistentQualifiers(split.Quals);
4007  }
4008
4009  return getQualifiedType(type, qs);
4010}
4011
4012/// getConstantArrayElementCount - Returns number of constant array elements.
4013uint64_t
4014ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
4015  uint64_t ElementCount = 1;
4016  do {
4017    ElementCount *= CA->getSize().getZExtValue();
4018    CA = dyn_cast_or_null<ConstantArrayType>(
4019      CA->getElementType()->getAsArrayTypeUnsafe());
4020  } while (CA);
4021  return ElementCount;
4022}
4023
4024/// getFloatingRank - Return a relative rank for floating point types.
4025/// This routine will assert if passed a built-in type that isn't a float.
4026static FloatingRank getFloatingRank(QualType T) {
4027  if (const ComplexType *CT = T->getAs<ComplexType>())
4028    return getFloatingRank(CT->getElementType());
4029
4030  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
4031  switch (T->getAs<BuiltinType>()->getKind()) {
4032  default: llvm_unreachable("getFloatingRank(): not a floating type");
4033  case BuiltinType::Half:       return HalfRank;
4034  case BuiltinType::Float:      return FloatRank;
4035  case BuiltinType::Double:     return DoubleRank;
4036  case BuiltinType::LongDouble: return LongDoubleRank;
4037  }
4038}
4039
4040/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
4041/// point or a complex type (based on typeDomain/typeSize).
4042/// 'typeDomain' is a real floating point or complex type.
4043/// 'typeSize' is a real floating point or complex type.
4044QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
4045                                                       QualType Domain) const {
4046  FloatingRank EltRank = getFloatingRank(Size);
4047  if (Domain->isComplexType()) {
4048    switch (EltRank) {
4049    case HalfRank: llvm_unreachable("Complex half is not supported");
4050    case FloatRank:      return FloatComplexTy;
4051    case DoubleRank:     return DoubleComplexTy;
4052    case LongDoubleRank: return LongDoubleComplexTy;
4053    }
4054  }
4055
4056  assert(Domain->isRealFloatingType() && "Unknown domain!");
4057  switch (EltRank) {
4058  case HalfRank: llvm_unreachable("Half ranks are not valid here");
4059  case FloatRank:      return FloatTy;
4060  case DoubleRank:     return DoubleTy;
4061  case LongDoubleRank: return LongDoubleTy;
4062  }
4063  llvm_unreachable("getFloatingRank(): illegal value for rank");
4064}
4065
4066/// getFloatingTypeOrder - Compare the rank of the two specified floating
4067/// point types, ignoring the domain of the type (i.e. 'double' ==
4068/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
4069/// LHS < RHS, return -1.
4070int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
4071  FloatingRank LHSR = getFloatingRank(LHS);
4072  FloatingRank RHSR = getFloatingRank(RHS);
4073
4074  if (LHSR == RHSR)
4075    return 0;
4076  if (LHSR > RHSR)
4077    return 1;
4078  return -1;
4079}
4080
4081/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
4082/// routine will assert if passed a built-in type that isn't an integer or enum,
4083/// or if it is not canonicalized.
4084unsigned ASTContext::getIntegerRank(const Type *T) const {
4085  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
4086
4087  switch (cast<BuiltinType>(T)->getKind()) {
4088  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
4089  case BuiltinType::Bool:
4090    return 1 + (getIntWidth(BoolTy) << 3);
4091  case BuiltinType::Char_S:
4092  case BuiltinType::Char_U:
4093  case BuiltinType::SChar:
4094  case BuiltinType::UChar:
4095    return 2 + (getIntWidth(CharTy) << 3);
4096  case BuiltinType::Short:
4097  case BuiltinType::UShort:
4098    return 3 + (getIntWidth(ShortTy) << 3);
4099  case BuiltinType::Int:
4100  case BuiltinType::UInt:
4101    return 4 + (getIntWidth(IntTy) << 3);
4102  case BuiltinType::Long:
4103  case BuiltinType::ULong:
4104    return 5 + (getIntWidth(LongTy) << 3);
4105  case BuiltinType::LongLong:
4106  case BuiltinType::ULongLong:
4107    return 6 + (getIntWidth(LongLongTy) << 3);
4108  case BuiltinType::Int128:
4109  case BuiltinType::UInt128:
4110    return 7 + (getIntWidth(Int128Ty) << 3);
4111  }
4112}
4113
4114/// \brief Whether this is a promotable bitfield reference according
4115/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
4116///
4117/// \returns the type this bit-field will promote to, or NULL if no
4118/// promotion occurs.
4119QualType ASTContext::isPromotableBitField(Expr *E) const {
4120  if (E->isTypeDependent() || E->isValueDependent())
4121    return QualType();
4122
4123  FieldDecl *Field = E->getBitField();
4124  if (!Field)
4125    return QualType();
4126
4127  QualType FT = Field->getType();
4128
4129  uint64_t BitWidth = Field->getBitWidthValue(*this);
4130  uint64_t IntSize = getTypeSize(IntTy);
4131  // GCC extension compatibility: if the bit-field size is less than or equal
4132  // to the size of int, it gets promoted no matter what its type is.
4133  // For instance, unsigned long bf : 4 gets promoted to signed int.
4134  if (BitWidth < IntSize)
4135    return IntTy;
4136
4137  if (BitWidth == IntSize)
4138    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
4139
4140  // Types bigger than int are not subject to promotions, and therefore act
4141  // like the base type.
4142  // FIXME: This doesn't quite match what gcc does, but what gcc does here
4143  // is ridiculous.
4144  return QualType();
4145}
4146
4147/// getPromotedIntegerType - Returns the type that Promotable will
4148/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
4149/// integer type.
4150QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
4151  assert(!Promotable.isNull());
4152  assert(Promotable->isPromotableIntegerType());
4153  if (const EnumType *ET = Promotable->getAs<EnumType>())
4154    return ET->getDecl()->getPromotionType();
4155
4156  if (const BuiltinType *BT = Promotable->getAs<BuiltinType>()) {
4157    // C++ [conv.prom]: A prvalue of type char16_t, char32_t, or wchar_t
4158    // (3.9.1) can be converted to a prvalue of the first of the following
4159    // types that can represent all the values of its underlying type:
4160    // int, unsigned int, long int, unsigned long int, long long int, or
4161    // unsigned long long int [...]
4162    // FIXME: Is there some better way to compute this?
4163    if (BT->getKind() == BuiltinType::WChar_S ||
4164        BT->getKind() == BuiltinType::WChar_U ||
4165        BT->getKind() == BuiltinType::Char16 ||
4166        BT->getKind() == BuiltinType::Char32) {
4167      bool FromIsSigned = BT->getKind() == BuiltinType::WChar_S;
4168      uint64_t FromSize = getTypeSize(BT);
4169      QualType PromoteTypes[] = { IntTy, UnsignedIntTy, LongTy, UnsignedLongTy,
4170                                  LongLongTy, UnsignedLongLongTy };
4171      for (size_t Idx = 0; Idx < llvm::array_lengthof(PromoteTypes); ++Idx) {
4172        uint64_t ToSize = getTypeSize(PromoteTypes[Idx]);
4173        if (FromSize < ToSize ||
4174            (FromSize == ToSize &&
4175             FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType()))
4176          return PromoteTypes[Idx];
4177      }
4178      llvm_unreachable("char type should fit into long long");
4179    }
4180  }
4181
4182  // At this point, we should have a signed or unsigned integer type.
4183  if (Promotable->isSignedIntegerType())
4184    return IntTy;
4185  uint64_t PromotableSize = getIntWidth(Promotable);
4186  uint64_t IntSize = getIntWidth(IntTy);
4187  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
4188  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
4189}
4190
4191/// \brief Recurses in pointer/array types until it finds an objc retainable
4192/// type and returns its ownership.
4193Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
4194  while (!T.isNull()) {
4195    if (T.getObjCLifetime() != Qualifiers::OCL_None)
4196      return T.getObjCLifetime();
4197    if (T->isArrayType())
4198      T = getBaseElementType(T);
4199    else if (const PointerType *PT = T->getAs<PointerType>())
4200      T = PT->getPointeeType();
4201    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4202      T = RT->getPointeeType();
4203    else
4204      break;
4205  }
4206
4207  return Qualifiers::OCL_None;
4208}
4209
4210/// getIntegerTypeOrder - Returns the highest ranked integer type:
4211/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
4212/// LHS < RHS, return -1.
4213int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
4214  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
4215  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
4216  if (LHSC == RHSC) return 0;
4217
4218  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
4219  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
4220
4221  unsigned LHSRank = getIntegerRank(LHSC);
4222  unsigned RHSRank = getIntegerRank(RHSC);
4223
4224  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
4225    if (LHSRank == RHSRank) return 0;
4226    return LHSRank > RHSRank ? 1 : -1;
4227  }
4228
4229  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
4230  if (LHSUnsigned) {
4231    // If the unsigned [LHS] type is larger, return it.
4232    if (LHSRank >= RHSRank)
4233      return 1;
4234
4235    // If the signed type can represent all values of the unsigned type, it
4236    // wins.  Because we are dealing with 2's complement and types that are
4237    // powers of two larger than each other, this is always safe.
4238    return -1;
4239  }
4240
4241  // If the unsigned [RHS] type is larger, return it.
4242  if (RHSRank >= LHSRank)
4243    return -1;
4244
4245  // If the signed type can represent all values of the unsigned type, it
4246  // wins.  Because we are dealing with 2's complement and types that are
4247  // powers of two larger than each other, this is always safe.
4248  return 1;
4249}
4250
4251static RecordDecl *
4252CreateRecordDecl(const ASTContext &Ctx, RecordDecl::TagKind TK,
4253                 DeclContext *DC, IdentifierInfo *Id) {
4254  SourceLocation Loc;
4255  if (Ctx.getLangOpts().CPlusPlus)
4256    return CXXRecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
4257  else
4258    return RecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
4259}
4260
4261// getCFConstantStringType - Return the type used for constant CFStrings.
4262QualType ASTContext::getCFConstantStringType() const {
4263  if (!CFConstantStringTypeDecl) {
4264    CFConstantStringTypeDecl =
4265      CreateRecordDecl(*this, TTK_Struct, TUDecl,
4266                       &Idents.get("NSConstantString"));
4267    CFConstantStringTypeDecl->startDefinition();
4268
4269    QualType FieldTypes[4];
4270
4271    // const int *isa;
4272    FieldTypes[0] = getPointerType(IntTy.withConst());
4273    // int flags;
4274    FieldTypes[1] = IntTy;
4275    // const char *str;
4276    FieldTypes[2] = getPointerType(CharTy.withConst());
4277    // long length;
4278    FieldTypes[3] = LongTy;
4279
4280    // Create fields
4281    for (unsigned i = 0; i < 4; ++i) {
4282      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
4283                                           SourceLocation(),
4284                                           SourceLocation(), 0,
4285                                           FieldTypes[i], /*TInfo=*/0,
4286                                           /*BitWidth=*/0,
4287                                           /*Mutable=*/false,
4288                                           ICIS_NoInit);
4289      Field->setAccess(AS_public);
4290      CFConstantStringTypeDecl->addDecl(Field);
4291    }
4292
4293    CFConstantStringTypeDecl->completeDefinition();
4294  }
4295
4296  return getTagDeclType(CFConstantStringTypeDecl);
4297}
4298
4299QualType ASTContext::getObjCSuperType() const {
4300  if (ObjCSuperType.isNull()) {
4301    RecordDecl *ObjCSuperTypeDecl  =
4302      CreateRecordDecl(*this, TTK_Struct, TUDecl, &Idents.get("objc_super"));
4303    TUDecl->addDecl(ObjCSuperTypeDecl);
4304    ObjCSuperType = getTagDeclType(ObjCSuperTypeDecl);
4305  }
4306  return ObjCSuperType;
4307}
4308
4309void ASTContext::setCFConstantStringType(QualType T) {
4310  const RecordType *Rec = T->getAs<RecordType>();
4311  assert(Rec && "Invalid CFConstantStringType");
4312  CFConstantStringTypeDecl = Rec->getDecl();
4313}
4314
4315QualType ASTContext::getBlockDescriptorType() const {
4316  if (BlockDescriptorType)
4317    return getTagDeclType(BlockDescriptorType);
4318
4319  RecordDecl *T;
4320  // FIXME: Needs the FlagAppleBlock bit.
4321  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
4322                       &Idents.get("__block_descriptor"));
4323  T->startDefinition();
4324
4325  QualType FieldTypes[] = {
4326    UnsignedLongTy,
4327    UnsignedLongTy,
4328  };
4329
4330  const char *FieldNames[] = {
4331    "reserved",
4332    "Size"
4333  };
4334
4335  for (size_t i = 0; i < 2; ++i) {
4336    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
4337                                         SourceLocation(),
4338                                         &Idents.get(FieldNames[i]),
4339                                         FieldTypes[i], /*TInfo=*/0,
4340                                         /*BitWidth=*/0,
4341                                         /*Mutable=*/false,
4342                                         ICIS_NoInit);
4343    Field->setAccess(AS_public);
4344    T->addDecl(Field);
4345  }
4346
4347  T->completeDefinition();
4348
4349  BlockDescriptorType = T;
4350
4351  return getTagDeclType(BlockDescriptorType);
4352}
4353
4354QualType ASTContext::getBlockDescriptorExtendedType() const {
4355  if (BlockDescriptorExtendedType)
4356    return getTagDeclType(BlockDescriptorExtendedType);
4357
4358  RecordDecl *T;
4359  // FIXME: Needs the FlagAppleBlock bit.
4360  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
4361                       &Idents.get("__block_descriptor_withcopydispose"));
4362  T->startDefinition();
4363
4364  QualType FieldTypes[] = {
4365    UnsignedLongTy,
4366    UnsignedLongTy,
4367    getPointerType(VoidPtrTy),
4368    getPointerType(VoidPtrTy)
4369  };
4370
4371  const char *FieldNames[] = {
4372    "reserved",
4373    "Size",
4374    "CopyFuncPtr",
4375    "DestroyFuncPtr"
4376  };
4377
4378  for (size_t i = 0; i < 4; ++i) {
4379    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
4380                                         SourceLocation(),
4381                                         &Idents.get(FieldNames[i]),
4382                                         FieldTypes[i], /*TInfo=*/0,
4383                                         /*BitWidth=*/0,
4384                                         /*Mutable=*/false,
4385                                         ICIS_NoInit);
4386    Field->setAccess(AS_public);
4387    T->addDecl(Field);
4388  }
4389
4390  T->completeDefinition();
4391
4392  BlockDescriptorExtendedType = T;
4393
4394  return getTagDeclType(BlockDescriptorExtendedType);
4395}
4396
4397/// BlockRequiresCopying - Returns true if byref variable "D" of type "Ty"
4398/// requires copy/dispose. Note that this must match the logic
4399/// in buildByrefHelpers.
4400bool ASTContext::BlockRequiresCopying(QualType Ty,
4401                                      const VarDecl *D) {
4402  if (const CXXRecordDecl *record = Ty->getAsCXXRecordDecl()) {
4403    const Expr *copyExpr = getBlockVarCopyInits(D);
4404    if (!copyExpr && record->hasTrivialDestructor()) return false;
4405
4406    return true;
4407  }
4408
4409  if (!Ty->isObjCRetainableType()) return false;
4410
4411  Qualifiers qs = Ty.getQualifiers();
4412
4413  // If we have lifetime, that dominates.
4414  if (Qualifiers::ObjCLifetime lifetime = qs.getObjCLifetime()) {
4415    assert(getLangOpts().ObjCAutoRefCount);
4416
4417    switch (lifetime) {
4418      case Qualifiers::OCL_None: llvm_unreachable("impossible");
4419
4420      // These are just bits as far as the runtime is concerned.
4421      case Qualifiers::OCL_ExplicitNone:
4422      case Qualifiers::OCL_Autoreleasing:
4423        return false;
4424
4425      // Tell the runtime that this is ARC __weak, called by the
4426      // byref routines.
4427      case Qualifiers::OCL_Weak:
4428      // ARC __strong __block variables need to be retained.
4429      case Qualifiers::OCL_Strong:
4430        return true;
4431    }
4432    llvm_unreachable("fell out of lifetime switch!");
4433  }
4434  return (Ty->isBlockPointerType() || isObjCNSObjectType(Ty) ||
4435          Ty->isObjCObjectPointerType());
4436}
4437
4438bool ASTContext::getByrefLifetime(QualType Ty,
4439                              Qualifiers::ObjCLifetime &LifeTime,
4440                              bool &HasByrefExtendedLayout) const {
4441
4442  if (!getLangOpts().ObjC1 ||
4443      getLangOpts().getGC() != LangOptions::NonGC)
4444    return false;
4445
4446  HasByrefExtendedLayout = false;
4447  if (Ty->isRecordType()) {
4448    HasByrefExtendedLayout = true;
4449    LifeTime = Qualifiers::OCL_None;
4450  }
4451  else if (getLangOpts().ObjCAutoRefCount)
4452    LifeTime = Ty.getObjCLifetime();
4453  // MRR.
4454  else if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4455    LifeTime = Qualifiers::OCL_ExplicitNone;
4456  else
4457    LifeTime = Qualifiers::OCL_None;
4458  return true;
4459}
4460
4461TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
4462  if (!ObjCInstanceTypeDecl)
4463    ObjCInstanceTypeDecl = TypedefDecl::Create(*this,
4464                                               getTranslationUnitDecl(),
4465                                               SourceLocation(),
4466                                               SourceLocation(),
4467                                               &Idents.get("instancetype"),
4468                                     getTrivialTypeSourceInfo(getObjCIdType()));
4469  return ObjCInstanceTypeDecl;
4470}
4471
4472// This returns true if a type has been typedefed to BOOL:
4473// typedef <type> BOOL;
4474static bool isTypeTypedefedAsBOOL(QualType T) {
4475  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
4476    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
4477      return II->isStr("BOOL");
4478
4479  return false;
4480}
4481
4482/// getObjCEncodingTypeSize returns size of type for objective-c encoding
4483/// purpose.
4484CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
4485  if (!type->isIncompleteArrayType() && type->isIncompleteType())
4486    return CharUnits::Zero();
4487
4488  CharUnits sz = getTypeSizeInChars(type);
4489
4490  // Make all integer and enum types at least as large as an int
4491  if (sz.isPositive() && type->isIntegralOrEnumerationType())
4492    sz = std::max(sz, getTypeSizeInChars(IntTy));
4493  // Treat arrays as pointers, since that's how they're passed in.
4494  else if (type->isArrayType())
4495    sz = getTypeSizeInChars(VoidPtrTy);
4496  return sz;
4497}
4498
4499static inline
4500std::string charUnitsToString(const CharUnits &CU) {
4501  return llvm::itostr(CU.getQuantity());
4502}
4503
4504/// getObjCEncodingForBlock - Return the encoded type for this block
4505/// declaration.
4506std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
4507  std::string S;
4508
4509  const BlockDecl *Decl = Expr->getBlockDecl();
4510  QualType BlockTy =
4511      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
4512  // Encode result type.
4513  if (getLangOpts().EncodeExtendedBlockSig)
4514    getObjCEncodingForMethodParameter(Decl::OBJC_TQ_None,
4515                            BlockTy->getAs<FunctionType>()->getResultType(),
4516                            S, true /*Extended*/);
4517  else
4518    getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(),
4519                           S);
4520  // Compute size of all parameters.
4521  // Start with computing size of a pointer in number of bytes.
4522  // FIXME: There might(should) be a better way of doing this computation!
4523  SourceLocation Loc;
4524  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4525  CharUnits ParmOffset = PtrSize;
4526  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
4527       E = Decl->param_end(); PI != E; ++PI) {
4528    QualType PType = (*PI)->getType();
4529    CharUnits sz = getObjCEncodingTypeSize(PType);
4530    if (sz.isZero())
4531      continue;
4532    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
4533    ParmOffset += sz;
4534  }
4535  // Size of the argument frame
4536  S += charUnitsToString(ParmOffset);
4537  // Block pointer and offset.
4538  S += "@?0";
4539
4540  // Argument types.
4541  ParmOffset = PtrSize;
4542  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
4543       Decl->param_end(); PI != E; ++PI) {
4544    ParmVarDecl *PVDecl = *PI;
4545    QualType PType = PVDecl->getOriginalType();
4546    if (const ArrayType *AT =
4547          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4548      // Use array's original type only if it has known number of
4549      // elements.
4550      if (!isa<ConstantArrayType>(AT))
4551        PType = PVDecl->getType();
4552    } else if (PType->isFunctionType())
4553      PType = PVDecl->getType();
4554    if (getLangOpts().EncodeExtendedBlockSig)
4555      getObjCEncodingForMethodParameter(Decl::OBJC_TQ_None, PType,
4556                                      S, true /*Extended*/);
4557    else
4558      getObjCEncodingForType(PType, S);
4559    S += charUnitsToString(ParmOffset);
4560    ParmOffset += getObjCEncodingTypeSize(PType);
4561  }
4562
4563  return S;
4564}
4565
4566bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
4567                                                std::string& S) {
4568  // Encode result type.
4569  getObjCEncodingForType(Decl->getResultType(), S);
4570  CharUnits ParmOffset;
4571  // Compute size of all parameters.
4572  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4573       E = Decl->param_end(); PI != E; ++PI) {
4574    QualType PType = (*PI)->getType();
4575    CharUnits sz = getObjCEncodingTypeSize(PType);
4576    if (sz.isZero())
4577      continue;
4578
4579    assert (sz.isPositive() &&
4580        "getObjCEncodingForFunctionDecl - Incomplete param type");
4581    ParmOffset += sz;
4582  }
4583  S += charUnitsToString(ParmOffset);
4584  ParmOffset = CharUnits::Zero();
4585
4586  // Argument types.
4587  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4588       E = Decl->param_end(); PI != E; ++PI) {
4589    ParmVarDecl *PVDecl = *PI;
4590    QualType PType = PVDecl->getOriginalType();
4591    if (const ArrayType *AT =
4592          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4593      // Use array's original type only if it has known number of
4594      // elements.
4595      if (!isa<ConstantArrayType>(AT))
4596        PType = PVDecl->getType();
4597    } else if (PType->isFunctionType())
4598      PType = PVDecl->getType();
4599    getObjCEncodingForType(PType, S);
4600    S += charUnitsToString(ParmOffset);
4601    ParmOffset += getObjCEncodingTypeSize(PType);
4602  }
4603
4604  return false;
4605}
4606
4607/// getObjCEncodingForMethodParameter - Return the encoded type for a single
4608/// method parameter or return type. If Extended, include class names and
4609/// block object types.
4610void ASTContext::getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
4611                                                   QualType T, std::string& S,
4612                                                   bool Extended) const {
4613  // Encode type qualifer, 'in', 'inout', etc. for the parameter.
4614  getObjCEncodingForTypeQualifier(QT, S);
4615  // Encode parameter type.
4616  getObjCEncodingForTypeImpl(T, S, true, true, 0,
4617                             true     /*OutermostType*/,
4618                             false    /*EncodingProperty*/,
4619                             false    /*StructField*/,
4620                             Extended /*EncodeBlockParameters*/,
4621                             Extended /*EncodeClassNames*/);
4622}
4623
4624/// getObjCEncodingForMethodDecl - Return the encoded type for this method
4625/// declaration.
4626bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
4627                                              std::string& S,
4628                                              bool Extended) const {
4629  // FIXME: This is not very efficient.
4630  // Encode return type.
4631  getObjCEncodingForMethodParameter(Decl->getObjCDeclQualifier(),
4632                                    Decl->getResultType(), S, Extended);
4633  // Compute size of all parameters.
4634  // Start with computing size of a pointer in number of bytes.
4635  // FIXME: There might(should) be a better way of doing this computation!
4636  SourceLocation Loc;
4637  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4638  // The first two arguments (self and _cmd) are pointers; account for
4639  // their size.
4640  CharUnits ParmOffset = 2 * PtrSize;
4641  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4642       E = Decl->sel_param_end(); PI != E; ++PI) {
4643    QualType PType = (*PI)->getType();
4644    CharUnits sz = getObjCEncodingTypeSize(PType);
4645    if (sz.isZero())
4646      continue;
4647
4648    assert (sz.isPositive() &&
4649        "getObjCEncodingForMethodDecl - Incomplete param type");
4650    ParmOffset += sz;
4651  }
4652  S += charUnitsToString(ParmOffset);
4653  S += "@0:";
4654  S += charUnitsToString(PtrSize);
4655
4656  // Argument types.
4657  ParmOffset = 2 * PtrSize;
4658  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4659       E = Decl->sel_param_end(); PI != E; ++PI) {
4660    const ParmVarDecl *PVDecl = *PI;
4661    QualType PType = PVDecl->getOriginalType();
4662    if (const ArrayType *AT =
4663          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4664      // Use array's original type only if it has known number of
4665      // elements.
4666      if (!isa<ConstantArrayType>(AT))
4667        PType = PVDecl->getType();
4668    } else if (PType->isFunctionType())
4669      PType = PVDecl->getType();
4670    getObjCEncodingForMethodParameter(PVDecl->getObjCDeclQualifier(),
4671                                      PType, S, Extended);
4672    S += charUnitsToString(ParmOffset);
4673    ParmOffset += getObjCEncodingTypeSize(PType);
4674  }
4675
4676  return false;
4677}
4678
4679/// getObjCEncodingForPropertyDecl - Return the encoded type for this
4680/// property declaration. If non-NULL, Container must be either an
4681/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
4682/// NULL when getting encodings for protocol properties.
4683/// Property attributes are stored as a comma-delimited C string. The simple
4684/// attributes readonly and bycopy are encoded as single characters. The
4685/// parametrized attributes, getter=name, setter=name, and ivar=name, are
4686/// encoded as single characters, followed by an identifier. Property types
4687/// are also encoded as a parametrized attribute. The characters used to encode
4688/// these attributes are defined by the following enumeration:
4689/// @code
4690/// enum PropertyAttributes {
4691/// kPropertyReadOnly = 'R',   // property is read-only.
4692/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
4693/// kPropertyByref = '&',  // property is a reference to the value last assigned
4694/// kPropertyDynamic = 'D',    // property is dynamic
4695/// kPropertyGetter = 'G',     // followed by getter selector name
4696/// kPropertySetter = 'S',     // followed by setter selector name
4697/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
4698/// kPropertyType = 'T'              // followed by old-style type encoding.
4699/// kPropertyWeak = 'W'              // 'weak' property
4700/// kPropertyStrong = 'P'            // property GC'able
4701/// kPropertyNonAtomic = 'N'         // property non-atomic
4702/// };
4703/// @endcode
4704void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
4705                                                const Decl *Container,
4706                                                std::string& S) const {
4707  // Collect information from the property implementation decl(s).
4708  bool Dynamic = false;
4709  ObjCPropertyImplDecl *SynthesizePID = 0;
4710
4711  // FIXME: Duplicated code due to poor abstraction.
4712  if (Container) {
4713    if (const ObjCCategoryImplDecl *CID =
4714        dyn_cast<ObjCCategoryImplDecl>(Container)) {
4715      for (ObjCCategoryImplDecl::propimpl_iterator
4716             i = CID->propimpl_begin(), e = CID->propimpl_end();
4717           i != e; ++i) {
4718        ObjCPropertyImplDecl *PID = *i;
4719        if (PID->getPropertyDecl() == PD) {
4720          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4721            Dynamic = true;
4722          } else {
4723            SynthesizePID = PID;
4724          }
4725        }
4726      }
4727    } else {
4728      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
4729      for (ObjCCategoryImplDecl::propimpl_iterator
4730             i = OID->propimpl_begin(), e = OID->propimpl_end();
4731           i != e; ++i) {
4732        ObjCPropertyImplDecl *PID = *i;
4733        if (PID->getPropertyDecl() == PD) {
4734          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4735            Dynamic = true;
4736          } else {
4737            SynthesizePID = PID;
4738          }
4739        }
4740      }
4741    }
4742  }
4743
4744  // FIXME: This is not very efficient.
4745  S = "T";
4746
4747  // Encode result type.
4748  // GCC has some special rules regarding encoding of properties which
4749  // closely resembles encoding of ivars.
4750  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
4751                             true /* outermost type */,
4752                             true /* encoding for property */);
4753
4754  if (PD->isReadOnly()) {
4755    S += ",R";
4756  } else {
4757    switch (PD->getSetterKind()) {
4758    case ObjCPropertyDecl::Assign: break;
4759    case ObjCPropertyDecl::Copy:   S += ",C"; break;
4760    case ObjCPropertyDecl::Retain: S += ",&"; break;
4761    case ObjCPropertyDecl::Weak:   S += ",W"; break;
4762    }
4763  }
4764
4765  // It really isn't clear at all what this means, since properties
4766  // are "dynamic by default".
4767  if (Dynamic)
4768    S += ",D";
4769
4770  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
4771    S += ",N";
4772
4773  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
4774    S += ",G";
4775    S += PD->getGetterName().getAsString();
4776  }
4777
4778  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
4779    S += ",S";
4780    S += PD->getSetterName().getAsString();
4781  }
4782
4783  if (SynthesizePID) {
4784    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
4785    S += ",V";
4786    S += OID->getNameAsString();
4787  }
4788
4789  // FIXME: OBJCGC: weak & strong
4790}
4791
4792/// getLegacyIntegralTypeEncoding -
4793/// Another legacy compatibility encoding: 32-bit longs are encoded as
4794/// 'l' or 'L' , but not always.  For typedefs, we need to use
4795/// 'i' or 'I' instead if encoding a struct field, or a pointer!
4796///
4797void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
4798  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
4799    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
4800      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
4801        PointeeTy = UnsignedIntTy;
4802      else
4803        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
4804          PointeeTy = IntTy;
4805    }
4806  }
4807}
4808
4809void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
4810                                        const FieldDecl *Field) const {
4811  // We follow the behavior of gcc, expanding structures which are
4812  // directly pointed to, and expanding embedded structures. Note that
4813  // these rules are sufficient to prevent recursive encoding of the
4814  // same type.
4815  getObjCEncodingForTypeImpl(T, S, true, true, Field,
4816                             true /* outermost type */);
4817}
4818
4819static char getObjCEncodingForPrimitiveKind(const ASTContext *C,
4820                                            BuiltinType::Kind kind) {
4821    switch (kind) {
4822    case BuiltinType::Void:       return 'v';
4823    case BuiltinType::Bool:       return 'B';
4824    case BuiltinType::Char_U:
4825    case BuiltinType::UChar:      return 'C';
4826    case BuiltinType::Char16:
4827    case BuiltinType::UShort:     return 'S';
4828    case BuiltinType::Char32:
4829    case BuiltinType::UInt:       return 'I';
4830    case BuiltinType::ULong:
4831        return C->getTargetInfo().getLongWidth() == 32 ? 'L' : 'Q';
4832    case BuiltinType::UInt128:    return 'T';
4833    case BuiltinType::ULongLong:  return 'Q';
4834    case BuiltinType::Char_S:
4835    case BuiltinType::SChar:      return 'c';
4836    case BuiltinType::Short:      return 's';
4837    case BuiltinType::WChar_S:
4838    case BuiltinType::WChar_U:
4839    case BuiltinType::Int:        return 'i';
4840    case BuiltinType::Long:
4841      return C->getTargetInfo().getLongWidth() == 32 ? 'l' : 'q';
4842    case BuiltinType::LongLong:   return 'q';
4843    case BuiltinType::Int128:     return 't';
4844    case BuiltinType::Float:      return 'f';
4845    case BuiltinType::Double:     return 'd';
4846    case BuiltinType::LongDouble: return 'D';
4847    case BuiltinType::NullPtr:    return '*'; // like char*
4848
4849    case BuiltinType::Half:
4850      // FIXME: potentially need @encodes for these!
4851      return ' ';
4852
4853    case BuiltinType::ObjCId:
4854    case BuiltinType::ObjCClass:
4855    case BuiltinType::ObjCSel:
4856      llvm_unreachable("@encoding ObjC primitive type");
4857
4858    // OpenCL and placeholder types don't need @encodings.
4859    case BuiltinType::OCLImage1d:
4860    case BuiltinType::OCLImage1dArray:
4861    case BuiltinType::OCLImage1dBuffer:
4862    case BuiltinType::OCLImage2d:
4863    case BuiltinType::OCLImage2dArray:
4864    case BuiltinType::OCLImage3d:
4865    case BuiltinType::Dependent:
4866#define BUILTIN_TYPE(KIND, ID)
4867#define PLACEHOLDER_TYPE(KIND, ID) \
4868    case BuiltinType::KIND:
4869#include "clang/AST/BuiltinTypes.def"
4870      llvm_unreachable("invalid builtin type for @encode");
4871    }
4872}
4873
4874static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
4875  EnumDecl *Enum = ET->getDecl();
4876
4877  // The encoding of an non-fixed enum type is always 'i', regardless of size.
4878  if (!Enum->isFixed())
4879    return 'i';
4880
4881  // The encoding of a fixed enum type matches its fixed underlying type.
4882  const BuiltinType *BT = Enum->getIntegerType()->castAs<BuiltinType>();
4883  return getObjCEncodingForPrimitiveKind(C, BT->getKind());
4884}
4885
4886static void EncodeBitField(const ASTContext *Ctx, std::string& S,
4887                           QualType T, const FieldDecl *FD) {
4888  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
4889  S += 'b';
4890  // The NeXT runtime encodes bit fields as b followed by the number of bits.
4891  // The GNU runtime requires more information; bitfields are encoded as b,
4892  // then the offset (in bits) of the first element, then the type of the
4893  // bitfield, then the size in bits.  For example, in this structure:
4894  //
4895  // struct
4896  // {
4897  //    int integer;
4898  //    int flags:2;
4899  // };
4900  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
4901  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
4902  // information is not especially sensible, but we're stuck with it for
4903  // compatibility with GCC, although providing it breaks anything that
4904  // actually uses runtime introspection and wants to work on both runtimes...
4905  if (Ctx->getLangOpts().ObjCRuntime.isGNUFamily()) {
4906    const RecordDecl *RD = FD->getParent();
4907    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
4908    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
4909    if (const EnumType *ET = T->getAs<EnumType>())
4910      S += ObjCEncodingForEnumType(Ctx, ET);
4911    else {
4912      const BuiltinType *BT = T->castAs<BuiltinType>();
4913      S += getObjCEncodingForPrimitiveKind(Ctx, BT->getKind());
4914    }
4915  }
4916  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
4917}
4918
4919// FIXME: Use SmallString for accumulating string.
4920void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
4921                                            bool ExpandPointedToStructures,
4922                                            bool ExpandStructures,
4923                                            const FieldDecl *FD,
4924                                            bool OutermostType,
4925                                            bool EncodingProperty,
4926                                            bool StructField,
4927                                            bool EncodeBlockParameters,
4928                                            bool EncodeClassNames) const {
4929  CanQualType CT = getCanonicalType(T);
4930  switch (CT->getTypeClass()) {
4931  case Type::Builtin:
4932  case Type::Enum:
4933    if (FD && FD->isBitField())
4934      return EncodeBitField(this, S, T, FD);
4935    if (const BuiltinType *BT = dyn_cast<BuiltinType>(CT))
4936      S += getObjCEncodingForPrimitiveKind(this, BT->getKind());
4937    else
4938      S += ObjCEncodingForEnumType(this, cast<EnumType>(CT));
4939    return;
4940
4941  case Type::Complex: {
4942    const ComplexType *CT = T->castAs<ComplexType>();
4943    S += 'j';
4944    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
4945                               false);
4946    return;
4947  }
4948
4949  case Type::Atomic: {
4950    const AtomicType *AT = T->castAs<AtomicType>();
4951    S += 'A';
4952    getObjCEncodingForTypeImpl(AT->getValueType(), S, false, false, 0,
4953                               false, false);
4954    return;
4955  }
4956
4957  // encoding for pointer or reference types.
4958  case Type::Pointer:
4959  case Type::LValueReference:
4960  case Type::RValueReference: {
4961    QualType PointeeTy;
4962    if (isa<PointerType>(CT)) {
4963      const PointerType *PT = T->castAs<PointerType>();
4964      if (PT->isObjCSelType()) {
4965        S += ':';
4966        return;
4967      }
4968      PointeeTy = PT->getPointeeType();
4969    } else {
4970      PointeeTy = T->castAs<ReferenceType>()->getPointeeType();
4971    }
4972
4973    bool isReadOnly = false;
4974    // For historical/compatibility reasons, the read-only qualifier of the
4975    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
4976    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
4977    // Also, do not emit the 'r' for anything but the outermost type!
4978    if (isa<TypedefType>(T.getTypePtr())) {
4979      if (OutermostType && T.isConstQualified()) {
4980        isReadOnly = true;
4981        S += 'r';
4982      }
4983    } else if (OutermostType) {
4984      QualType P = PointeeTy;
4985      while (P->getAs<PointerType>())
4986        P = P->getAs<PointerType>()->getPointeeType();
4987      if (P.isConstQualified()) {
4988        isReadOnly = true;
4989        S += 'r';
4990      }
4991    }
4992    if (isReadOnly) {
4993      // Another legacy compatibility encoding. Some ObjC qualifier and type
4994      // combinations need to be rearranged.
4995      // Rewrite "in const" from "nr" to "rn"
4996      if (StringRef(S).endswith("nr"))
4997        S.replace(S.end()-2, S.end(), "rn");
4998    }
4999
5000    if (PointeeTy->isCharType()) {
5001      // char pointer types should be encoded as '*' unless it is a
5002      // type that has been typedef'd to 'BOOL'.
5003      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
5004        S += '*';
5005        return;
5006      }
5007    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
5008      // GCC binary compat: Need to convert "struct objc_class *" to "#".
5009      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
5010        S += '#';
5011        return;
5012      }
5013      // GCC binary compat: Need to convert "struct objc_object *" to "@".
5014      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
5015        S += '@';
5016        return;
5017      }
5018      // fall through...
5019    }
5020    S += '^';
5021    getLegacyIntegralTypeEncoding(PointeeTy);
5022
5023    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
5024                               NULL);
5025    return;
5026  }
5027
5028  case Type::ConstantArray:
5029  case Type::IncompleteArray:
5030  case Type::VariableArray: {
5031    const ArrayType *AT = cast<ArrayType>(CT);
5032
5033    if (isa<IncompleteArrayType>(AT) && !StructField) {
5034      // Incomplete arrays are encoded as a pointer to the array element.
5035      S += '^';
5036
5037      getObjCEncodingForTypeImpl(AT->getElementType(), S,
5038                                 false, ExpandStructures, FD);
5039    } else {
5040      S += '[';
5041
5042      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
5043        if (getTypeSize(CAT->getElementType()) == 0)
5044          S += '0';
5045        else
5046          S += llvm::utostr(CAT->getSize().getZExtValue());
5047      } else {
5048        //Variable length arrays are encoded as a regular array with 0 elements.
5049        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
5050               "Unknown array type!");
5051        S += '0';
5052      }
5053
5054      getObjCEncodingForTypeImpl(AT->getElementType(), S,
5055                                 false, ExpandStructures, FD);
5056      S += ']';
5057    }
5058    return;
5059  }
5060
5061  case Type::FunctionNoProto:
5062  case Type::FunctionProto:
5063    S += '?';
5064    return;
5065
5066  case Type::Record: {
5067    RecordDecl *RDecl = cast<RecordType>(CT)->getDecl();
5068    S += RDecl->isUnion() ? '(' : '{';
5069    // Anonymous structures print as '?'
5070    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
5071      S += II->getName();
5072      if (ClassTemplateSpecializationDecl *Spec
5073          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
5074        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
5075        std::string TemplateArgsStr
5076          = TemplateSpecializationType::PrintTemplateArgumentList(
5077                                            TemplateArgs.data(),
5078                                            TemplateArgs.size(),
5079                                            (*this).getPrintingPolicy());
5080
5081        S += TemplateArgsStr;
5082      }
5083    } else {
5084      S += '?';
5085    }
5086    if (ExpandStructures) {
5087      S += '=';
5088      if (!RDecl->isUnion()) {
5089        getObjCEncodingForStructureImpl(RDecl, S, FD);
5090      } else {
5091        for (RecordDecl::field_iterator Field = RDecl->field_begin(),
5092                                     FieldEnd = RDecl->field_end();
5093             Field != FieldEnd; ++Field) {
5094          if (FD) {
5095            S += '"';
5096            S += Field->getNameAsString();
5097            S += '"';
5098          }
5099
5100          // Special case bit-fields.
5101          if (Field->isBitField()) {
5102            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
5103                                       *Field);
5104          } else {
5105            QualType qt = Field->getType();
5106            getLegacyIntegralTypeEncoding(qt);
5107            getObjCEncodingForTypeImpl(qt, S, false, true,
5108                                       FD, /*OutermostType*/false,
5109                                       /*EncodingProperty*/false,
5110                                       /*StructField*/true);
5111          }
5112        }
5113      }
5114    }
5115    S += RDecl->isUnion() ? ')' : '}';
5116    return;
5117  }
5118
5119  case Type::BlockPointer: {
5120    const BlockPointerType *BT = T->castAs<BlockPointerType>();
5121    S += "@?"; // Unlike a pointer-to-function, which is "^?".
5122    if (EncodeBlockParameters) {
5123      const FunctionType *FT = BT->getPointeeType()->castAs<FunctionType>();
5124
5125      S += '<';
5126      // Block return type
5127      getObjCEncodingForTypeImpl(FT->getResultType(), S,
5128                                 ExpandPointedToStructures, ExpandStructures,
5129                                 FD,
5130                                 false /* OutermostType */,
5131                                 EncodingProperty,
5132                                 false /* StructField */,
5133                                 EncodeBlockParameters,
5134                                 EncodeClassNames);
5135      // Block self
5136      S += "@?";
5137      // Block parameters
5138      if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT)) {
5139        for (FunctionProtoType::arg_type_iterator I = FPT->arg_type_begin(),
5140               E = FPT->arg_type_end(); I && (I != E); ++I) {
5141          getObjCEncodingForTypeImpl(*I, S,
5142                                     ExpandPointedToStructures,
5143                                     ExpandStructures,
5144                                     FD,
5145                                     false /* OutermostType */,
5146                                     EncodingProperty,
5147                                     false /* StructField */,
5148                                     EncodeBlockParameters,
5149                                     EncodeClassNames);
5150        }
5151      }
5152      S += '>';
5153    }
5154    return;
5155  }
5156
5157  case Type::ObjCObject:
5158  case Type::ObjCInterface: {
5159    // Ignore protocol qualifiers when mangling at this level.
5160    T = T->castAs<ObjCObjectType>()->getBaseType();
5161
5162    // The assumption seems to be that this assert will succeed
5163    // because nested levels will have filtered out 'id' and 'Class'.
5164    const ObjCInterfaceType *OIT = T->castAs<ObjCInterfaceType>();
5165    // @encode(class_name)
5166    ObjCInterfaceDecl *OI = OIT->getDecl();
5167    S += '{';
5168    const IdentifierInfo *II = OI->getIdentifier();
5169    S += II->getName();
5170    S += '=';
5171    SmallVector<const ObjCIvarDecl*, 32> Ivars;
5172    DeepCollectObjCIvars(OI, true, Ivars);
5173    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
5174      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
5175      if (Field->isBitField())
5176        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
5177      else
5178        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD);
5179    }
5180    S += '}';
5181    return;
5182  }
5183
5184  case Type::ObjCObjectPointer: {
5185    const ObjCObjectPointerType *OPT = T->castAs<ObjCObjectPointerType>();
5186    if (OPT->isObjCIdType()) {
5187      S += '@';
5188      return;
5189    }
5190
5191    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
5192      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
5193      // Since this is a binary compatibility issue, need to consult with runtime
5194      // folks. Fortunately, this is a *very* obsure construct.
5195      S += '#';
5196      return;
5197    }
5198
5199    if (OPT->isObjCQualifiedIdType()) {
5200      getObjCEncodingForTypeImpl(getObjCIdType(), S,
5201                                 ExpandPointedToStructures,
5202                                 ExpandStructures, FD);
5203      if (FD || EncodingProperty || EncodeClassNames) {
5204        // Note that we do extended encoding of protocol qualifer list
5205        // Only when doing ivar or property encoding.
5206        S += '"';
5207        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
5208             E = OPT->qual_end(); I != E; ++I) {
5209          S += '<';
5210          S += (*I)->getNameAsString();
5211          S += '>';
5212        }
5213        S += '"';
5214      }
5215      return;
5216    }
5217
5218    QualType PointeeTy = OPT->getPointeeType();
5219    if (!EncodingProperty &&
5220        isa<TypedefType>(PointeeTy.getTypePtr())) {
5221      // Another historical/compatibility reason.
5222      // We encode the underlying type which comes out as
5223      // {...};
5224      S += '^';
5225      getObjCEncodingForTypeImpl(PointeeTy, S,
5226                                 false, ExpandPointedToStructures,
5227                                 NULL);
5228      return;
5229    }
5230
5231    S += '@';
5232    if (OPT->getInterfaceDecl() &&
5233        (FD || EncodingProperty || EncodeClassNames)) {
5234      S += '"';
5235      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
5236      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
5237           E = OPT->qual_end(); I != E; ++I) {
5238        S += '<';
5239        S += (*I)->getNameAsString();
5240        S += '>';
5241      }
5242      S += '"';
5243    }
5244    return;
5245  }
5246
5247  // gcc just blithely ignores member pointers.
5248  // FIXME: we shoul do better than that.  'M' is available.
5249  case Type::MemberPointer:
5250    return;
5251
5252  case Type::Vector:
5253  case Type::ExtVector:
5254    // This matches gcc's encoding, even though technically it is
5255    // insufficient.
5256    // FIXME. We should do a better job than gcc.
5257    return;
5258
5259#define ABSTRACT_TYPE(KIND, BASE)
5260#define TYPE(KIND, BASE)
5261#define DEPENDENT_TYPE(KIND, BASE) \
5262  case Type::KIND:
5263#define NON_CANONICAL_TYPE(KIND, BASE) \
5264  case Type::KIND:
5265#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(KIND, BASE) \
5266  case Type::KIND:
5267#include "clang/AST/TypeNodes.def"
5268    llvm_unreachable("@encode for dependent type!");
5269  }
5270  llvm_unreachable("bad type kind!");
5271}
5272
5273void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
5274                                                 std::string &S,
5275                                                 const FieldDecl *FD,
5276                                                 bool includeVBases) const {
5277  assert(RDecl && "Expected non-null RecordDecl");
5278  assert(!RDecl->isUnion() && "Should not be called for unions");
5279  if (!RDecl->getDefinition())
5280    return;
5281
5282  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
5283  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
5284  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
5285
5286  if (CXXRec) {
5287    for (CXXRecordDecl::base_class_iterator
5288           BI = CXXRec->bases_begin(),
5289           BE = CXXRec->bases_end(); BI != BE; ++BI) {
5290      if (!BI->isVirtual()) {
5291        CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
5292        if (base->isEmpty())
5293          continue;
5294        uint64_t offs = toBits(layout.getBaseClassOffset(base));
5295        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5296                                  std::make_pair(offs, base));
5297      }
5298    }
5299  }
5300
5301  unsigned i = 0;
5302  for (RecordDecl::field_iterator Field = RDecl->field_begin(),
5303                               FieldEnd = RDecl->field_end();
5304       Field != FieldEnd; ++Field, ++i) {
5305    uint64_t offs = layout.getFieldOffset(i);
5306    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5307                              std::make_pair(offs, *Field));
5308  }
5309
5310  if (CXXRec && includeVBases) {
5311    for (CXXRecordDecl::base_class_iterator
5312           BI = CXXRec->vbases_begin(),
5313           BE = CXXRec->vbases_end(); BI != BE; ++BI) {
5314      CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
5315      if (base->isEmpty())
5316        continue;
5317      uint64_t offs = toBits(layout.getVBaseClassOffset(base));
5318      if (FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
5319        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
5320                                  std::make_pair(offs, base));
5321    }
5322  }
5323
5324  CharUnits size;
5325  if (CXXRec) {
5326    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
5327  } else {
5328    size = layout.getSize();
5329  }
5330
5331  uint64_t CurOffs = 0;
5332  std::multimap<uint64_t, NamedDecl *>::iterator
5333    CurLayObj = FieldOrBaseOffsets.begin();
5334
5335  if (CXXRec && CXXRec->isDynamicClass() &&
5336      (CurLayObj == FieldOrBaseOffsets.end() || CurLayObj->first != 0)) {
5337    if (FD) {
5338      S += "\"_vptr$";
5339      std::string recname = CXXRec->getNameAsString();
5340      if (recname.empty()) recname = "?";
5341      S += recname;
5342      S += '"';
5343    }
5344    S += "^^?";
5345    CurOffs += getTypeSize(VoidPtrTy);
5346  }
5347
5348  if (!RDecl->hasFlexibleArrayMember()) {
5349    // Mark the end of the structure.
5350    uint64_t offs = toBits(size);
5351    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5352                              std::make_pair(offs, (NamedDecl*)0));
5353  }
5354
5355  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
5356    assert(CurOffs <= CurLayObj->first);
5357
5358    if (CurOffs < CurLayObj->first) {
5359      uint64_t padding = CurLayObj->first - CurOffs;
5360      // FIXME: There doesn't seem to be a way to indicate in the encoding that
5361      // packing/alignment of members is different that normal, in which case
5362      // the encoding will be out-of-sync with the real layout.
5363      // If the runtime switches to just consider the size of types without
5364      // taking into account alignment, we could make padding explicit in the
5365      // encoding (e.g. using arrays of chars). The encoding strings would be
5366      // longer then though.
5367      CurOffs += padding;
5368    }
5369
5370    NamedDecl *dcl = CurLayObj->second;
5371    if (dcl == 0)
5372      break; // reached end of structure.
5373
5374    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
5375      // We expand the bases without their virtual bases since those are going
5376      // in the initial structure. Note that this differs from gcc which
5377      // expands virtual bases each time one is encountered in the hierarchy,
5378      // making the encoding type bigger than it really is.
5379      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false);
5380      assert(!base->isEmpty());
5381      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
5382    } else {
5383      FieldDecl *field = cast<FieldDecl>(dcl);
5384      if (FD) {
5385        S += '"';
5386        S += field->getNameAsString();
5387        S += '"';
5388      }
5389
5390      if (field->isBitField()) {
5391        EncodeBitField(this, S, field->getType(), field);
5392        CurOffs += field->getBitWidthValue(*this);
5393      } else {
5394        QualType qt = field->getType();
5395        getLegacyIntegralTypeEncoding(qt);
5396        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
5397                                   /*OutermostType*/false,
5398                                   /*EncodingProperty*/false,
5399                                   /*StructField*/true);
5400        CurOffs += getTypeSize(field->getType());
5401      }
5402    }
5403  }
5404}
5405
5406void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
5407                                                 std::string& S) const {
5408  if (QT & Decl::OBJC_TQ_In)
5409    S += 'n';
5410  if (QT & Decl::OBJC_TQ_Inout)
5411    S += 'N';
5412  if (QT & Decl::OBJC_TQ_Out)
5413    S += 'o';
5414  if (QT & Decl::OBJC_TQ_Bycopy)
5415    S += 'O';
5416  if (QT & Decl::OBJC_TQ_Byref)
5417    S += 'R';
5418  if (QT & Decl::OBJC_TQ_Oneway)
5419    S += 'V';
5420}
5421
5422TypedefDecl *ASTContext::getObjCIdDecl() const {
5423  if (!ObjCIdDecl) {
5424    QualType T = getObjCObjectType(ObjCBuiltinIdTy, 0, 0);
5425    T = getObjCObjectPointerType(T);
5426    TypeSourceInfo *IdInfo = getTrivialTypeSourceInfo(T);
5427    ObjCIdDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
5428                                     getTranslationUnitDecl(),
5429                                     SourceLocation(), SourceLocation(),
5430                                     &Idents.get("id"), IdInfo);
5431  }
5432
5433  return ObjCIdDecl;
5434}
5435
5436TypedefDecl *ASTContext::getObjCSelDecl() const {
5437  if (!ObjCSelDecl) {
5438    QualType SelT = getPointerType(ObjCBuiltinSelTy);
5439    TypeSourceInfo *SelInfo = getTrivialTypeSourceInfo(SelT);
5440    ObjCSelDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
5441                                      getTranslationUnitDecl(),
5442                                      SourceLocation(), SourceLocation(),
5443                                      &Idents.get("SEL"), SelInfo);
5444  }
5445  return ObjCSelDecl;
5446}
5447
5448TypedefDecl *ASTContext::getObjCClassDecl() const {
5449  if (!ObjCClassDecl) {
5450    QualType T = getObjCObjectType(ObjCBuiltinClassTy, 0, 0);
5451    T = getObjCObjectPointerType(T);
5452    TypeSourceInfo *ClassInfo = getTrivialTypeSourceInfo(T);
5453    ObjCClassDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
5454                                        getTranslationUnitDecl(),
5455                                        SourceLocation(), SourceLocation(),
5456                                        &Idents.get("Class"), ClassInfo);
5457  }
5458
5459  return ObjCClassDecl;
5460}
5461
5462ObjCInterfaceDecl *ASTContext::getObjCProtocolDecl() const {
5463  if (!ObjCProtocolClassDecl) {
5464    ObjCProtocolClassDecl
5465      = ObjCInterfaceDecl::Create(*this, getTranslationUnitDecl(),
5466                                  SourceLocation(),
5467                                  &Idents.get("Protocol"),
5468                                  /*PrevDecl=*/0,
5469                                  SourceLocation(), true);
5470  }
5471
5472  return ObjCProtocolClassDecl;
5473}
5474
5475//===----------------------------------------------------------------------===//
5476// __builtin_va_list Construction Functions
5477//===----------------------------------------------------------------------===//
5478
5479static TypedefDecl *CreateCharPtrBuiltinVaListDecl(const ASTContext *Context) {
5480  // typedef char* __builtin_va_list;
5481  QualType CharPtrType = Context->getPointerType(Context->CharTy);
5482  TypeSourceInfo *TInfo
5483    = Context->getTrivialTypeSourceInfo(CharPtrType);
5484
5485  TypedefDecl *VaListTypeDecl
5486    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5487                          Context->getTranslationUnitDecl(),
5488                          SourceLocation(), SourceLocation(),
5489                          &Context->Idents.get("__builtin_va_list"),
5490                          TInfo);
5491  return VaListTypeDecl;
5492}
5493
5494static TypedefDecl *CreateVoidPtrBuiltinVaListDecl(const ASTContext *Context) {
5495  // typedef void* __builtin_va_list;
5496  QualType VoidPtrType = Context->getPointerType(Context->VoidTy);
5497  TypeSourceInfo *TInfo
5498    = Context->getTrivialTypeSourceInfo(VoidPtrType);
5499
5500  TypedefDecl *VaListTypeDecl
5501    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5502                          Context->getTranslationUnitDecl(),
5503                          SourceLocation(), SourceLocation(),
5504                          &Context->Idents.get("__builtin_va_list"),
5505                          TInfo);
5506  return VaListTypeDecl;
5507}
5508
5509static TypedefDecl *CreatePowerABIBuiltinVaListDecl(const ASTContext *Context) {
5510  // typedef struct __va_list_tag {
5511  RecordDecl *VaListTagDecl;
5512
5513  VaListTagDecl = CreateRecordDecl(*Context, TTK_Struct,
5514                                   Context->getTranslationUnitDecl(),
5515                                   &Context->Idents.get("__va_list_tag"));
5516  VaListTagDecl->startDefinition();
5517
5518  const size_t NumFields = 5;
5519  QualType FieldTypes[NumFields];
5520  const char *FieldNames[NumFields];
5521
5522  //   unsigned char gpr;
5523  FieldTypes[0] = Context->UnsignedCharTy;
5524  FieldNames[0] = "gpr";
5525
5526  //   unsigned char fpr;
5527  FieldTypes[1] = Context->UnsignedCharTy;
5528  FieldNames[1] = "fpr";
5529
5530  //   unsigned short reserved;
5531  FieldTypes[2] = Context->UnsignedShortTy;
5532  FieldNames[2] = "reserved";
5533
5534  //   void* overflow_arg_area;
5535  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
5536  FieldNames[3] = "overflow_arg_area";
5537
5538  //   void* reg_save_area;
5539  FieldTypes[4] = Context->getPointerType(Context->VoidTy);
5540  FieldNames[4] = "reg_save_area";
5541
5542  // Create fields
5543  for (unsigned i = 0; i < NumFields; ++i) {
5544    FieldDecl *Field = FieldDecl::Create(*Context, VaListTagDecl,
5545                                         SourceLocation(),
5546                                         SourceLocation(),
5547                                         &Context->Idents.get(FieldNames[i]),
5548                                         FieldTypes[i], /*TInfo=*/0,
5549                                         /*BitWidth=*/0,
5550                                         /*Mutable=*/false,
5551                                         ICIS_NoInit);
5552    Field->setAccess(AS_public);
5553    VaListTagDecl->addDecl(Field);
5554  }
5555  VaListTagDecl->completeDefinition();
5556  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
5557  Context->VaListTagTy = VaListTagType;
5558
5559  // } __va_list_tag;
5560  TypedefDecl *VaListTagTypedefDecl
5561    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5562                          Context->getTranslationUnitDecl(),
5563                          SourceLocation(), SourceLocation(),
5564                          &Context->Idents.get("__va_list_tag"),
5565                          Context->getTrivialTypeSourceInfo(VaListTagType));
5566  QualType VaListTagTypedefType =
5567    Context->getTypedefType(VaListTagTypedefDecl);
5568
5569  // typedef __va_list_tag __builtin_va_list[1];
5570  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
5571  QualType VaListTagArrayType
5572    = Context->getConstantArrayType(VaListTagTypedefType,
5573                                    Size, ArrayType::Normal, 0);
5574  TypeSourceInfo *TInfo
5575    = Context->getTrivialTypeSourceInfo(VaListTagArrayType);
5576  TypedefDecl *VaListTypedefDecl
5577    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5578                          Context->getTranslationUnitDecl(),
5579                          SourceLocation(), SourceLocation(),
5580                          &Context->Idents.get("__builtin_va_list"),
5581                          TInfo);
5582
5583  return VaListTypedefDecl;
5584}
5585
5586static TypedefDecl *
5587CreateX86_64ABIBuiltinVaListDecl(const ASTContext *Context) {
5588  // typedef struct __va_list_tag {
5589  RecordDecl *VaListTagDecl;
5590  VaListTagDecl = CreateRecordDecl(*Context, TTK_Struct,
5591                                   Context->getTranslationUnitDecl(),
5592                                   &Context->Idents.get("__va_list_tag"));
5593  VaListTagDecl->startDefinition();
5594
5595  const size_t NumFields = 4;
5596  QualType FieldTypes[NumFields];
5597  const char *FieldNames[NumFields];
5598
5599  //   unsigned gp_offset;
5600  FieldTypes[0] = Context->UnsignedIntTy;
5601  FieldNames[0] = "gp_offset";
5602
5603  //   unsigned fp_offset;
5604  FieldTypes[1] = Context->UnsignedIntTy;
5605  FieldNames[1] = "fp_offset";
5606
5607  //   void* overflow_arg_area;
5608  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
5609  FieldNames[2] = "overflow_arg_area";
5610
5611  //   void* reg_save_area;
5612  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
5613  FieldNames[3] = "reg_save_area";
5614
5615  // Create fields
5616  for (unsigned i = 0; i < NumFields; ++i) {
5617    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
5618                                         VaListTagDecl,
5619                                         SourceLocation(),
5620                                         SourceLocation(),
5621                                         &Context->Idents.get(FieldNames[i]),
5622                                         FieldTypes[i], /*TInfo=*/0,
5623                                         /*BitWidth=*/0,
5624                                         /*Mutable=*/false,
5625                                         ICIS_NoInit);
5626    Field->setAccess(AS_public);
5627    VaListTagDecl->addDecl(Field);
5628  }
5629  VaListTagDecl->completeDefinition();
5630  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
5631  Context->VaListTagTy = VaListTagType;
5632
5633  // } __va_list_tag;
5634  TypedefDecl *VaListTagTypedefDecl
5635    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5636                          Context->getTranslationUnitDecl(),
5637                          SourceLocation(), SourceLocation(),
5638                          &Context->Idents.get("__va_list_tag"),
5639                          Context->getTrivialTypeSourceInfo(VaListTagType));
5640  QualType VaListTagTypedefType =
5641    Context->getTypedefType(VaListTagTypedefDecl);
5642
5643  // typedef __va_list_tag __builtin_va_list[1];
5644  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
5645  QualType VaListTagArrayType
5646    = Context->getConstantArrayType(VaListTagTypedefType,
5647                                      Size, ArrayType::Normal,0);
5648  TypeSourceInfo *TInfo
5649    = Context->getTrivialTypeSourceInfo(VaListTagArrayType);
5650  TypedefDecl *VaListTypedefDecl
5651    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5652                          Context->getTranslationUnitDecl(),
5653                          SourceLocation(), SourceLocation(),
5654                          &Context->Idents.get("__builtin_va_list"),
5655                          TInfo);
5656
5657  return VaListTypedefDecl;
5658}
5659
5660static TypedefDecl *CreatePNaClABIBuiltinVaListDecl(const ASTContext *Context) {
5661  // typedef int __builtin_va_list[4];
5662  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 4);
5663  QualType IntArrayType
5664    = Context->getConstantArrayType(Context->IntTy,
5665				    Size, ArrayType::Normal, 0);
5666  TypedefDecl *VaListTypedefDecl
5667    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5668                          Context->getTranslationUnitDecl(),
5669                          SourceLocation(), SourceLocation(),
5670                          &Context->Idents.get("__builtin_va_list"),
5671                          Context->getTrivialTypeSourceInfo(IntArrayType));
5672
5673  return VaListTypedefDecl;
5674}
5675
5676static TypedefDecl *
5677CreateAAPCSABIBuiltinVaListDecl(const ASTContext *Context) {
5678  RecordDecl *VaListDecl;
5679  if (Context->getLangOpts().CPlusPlus) {
5680    // namespace std { struct __va_list {
5681    NamespaceDecl *NS;
5682    NS = NamespaceDecl::Create(const_cast<ASTContext &>(*Context),
5683                               Context->getTranslationUnitDecl(),
5684                               /*Inline*/false, SourceLocation(),
5685                               SourceLocation(), &Context->Idents.get("std"),
5686                               /*PrevDecl*/0);
5687
5688    VaListDecl = CXXRecordDecl::Create(*Context, TTK_Struct,
5689                                       Context->getTranslationUnitDecl(),
5690                                       SourceLocation(), SourceLocation(),
5691                                       &Context->Idents.get("__va_list"));
5692
5693    VaListDecl->setDeclContext(NS);
5694
5695  } else {
5696    // struct __va_list {
5697    VaListDecl = CreateRecordDecl(*Context, TTK_Struct,
5698                                  Context->getTranslationUnitDecl(),
5699                                  &Context->Idents.get("__va_list"));
5700  }
5701
5702  VaListDecl->startDefinition();
5703
5704  // void * __ap;
5705  FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
5706                                       VaListDecl,
5707                                       SourceLocation(),
5708                                       SourceLocation(),
5709                                       &Context->Idents.get("__ap"),
5710                                       Context->getPointerType(Context->VoidTy),
5711                                       /*TInfo=*/0,
5712                                       /*BitWidth=*/0,
5713                                       /*Mutable=*/false,
5714                                       ICIS_NoInit);
5715  Field->setAccess(AS_public);
5716  VaListDecl->addDecl(Field);
5717
5718  // };
5719  VaListDecl->completeDefinition();
5720
5721  // typedef struct __va_list __builtin_va_list;
5722  TypeSourceInfo *TInfo
5723    = Context->getTrivialTypeSourceInfo(Context->getRecordType(VaListDecl));
5724
5725  TypedefDecl *VaListTypeDecl
5726    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5727                          Context->getTranslationUnitDecl(),
5728                          SourceLocation(), SourceLocation(),
5729                          &Context->Idents.get("__builtin_va_list"),
5730                          TInfo);
5731
5732  return VaListTypeDecl;
5733}
5734
5735static TypedefDecl *CreateVaListDecl(const ASTContext *Context,
5736                                     TargetInfo::BuiltinVaListKind Kind) {
5737  switch (Kind) {
5738  case TargetInfo::CharPtrBuiltinVaList:
5739    return CreateCharPtrBuiltinVaListDecl(Context);
5740  case TargetInfo::VoidPtrBuiltinVaList:
5741    return CreateVoidPtrBuiltinVaListDecl(Context);
5742  case TargetInfo::PowerABIBuiltinVaList:
5743    return CreatePowerABIBuiltinVaListDecl(Context);
5744  case TargetInfo::X86_64ABIBuiltinVaList:
5745    return CreateX86_64ABIBuiltinVaListDecl(Context);
5746  case TargetInfo::PNaClABIBuiltinVaList:
5747    return CreatePNaClABIBuiltinVaListDecl(Context);
5748  case TargetInfo::AAPCSABIBuiltinVaList:
5749    return CreateAAPCSABIBuiltinVaListDecl(Context);
5750  }
5751
5752  llvm_unreachable("Unhandled __builtin_va_list type kind");
5753}
5754
5755TypedefDecl *ASTContext::getBuiltinVaListDecl() const {
5756  if (!BuiltinVaListDecl)
5757    BuiltinVaListDecl = CreateVaListDecl(this, Target->getBuiltinVaListKind());
5758
5759  return BuiltinVaListDecl;
5760}
5761
5762QualType ASTContext::getVaListTagType() const {
5763  // Force the creation of VaListTagTy by building the __builtin_va_list
5764  // declaration.
5765  if (VaListTagTy.isNull())
5766    (void) getBuiltinVaListDecl();
5767
5768  return VaListTagTy;
5769}
5770
5771void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
5772  assert(ObjCConstantStringType.isNull() &&
5773         "'NSConstantString' type already set!");
5774
5775  ObjCConstantStringType = getObjCInterfaceType(Decl);
5776}
5777
5778/// \brief Retrieve the template name that corresponds to a non-empty
5779/// lookup.
5780TemplateName
5781ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
5782                                      UnresolvedSetIterator End) const {
5783  unsigned size = End - Begin;
5784  assert(size > 1 && "set is not overloaded!");
5785
5786  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
5787                          size * sizeof(FunctionTemplateDecl*));
5788  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
5789
5790  NamedDecl **Storage = OT->getStorage();
5791  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
5792    NamedDecl *D = *I;
5793    assert(isa<FunctionTemplateDecl>(D) ||
5794           (isa<UsingShadowDecl>(D) &&
5795            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
5796    *Storage++ = D;
5797  }
5798
5799  return TemplateName(OT);
5800}
5801
5802/// \brief Retrieve the template name that represents a qualified
5803/// template name such as \c std::vector.
5804TemplateName
5805ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
5806                                     bool TemplateKeyword,
5807                                     TemplateDecl *Template) const {
5808  assert(NNS && "Missing nested-name-specifier in qualified template name");
5809
5810  // FIXME: Canonicalization?
5811  llvm::FoldingSetNodeID ID;
5812  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
5813
5814  void *InsertPos = 0;
5815  QualifiedTemplateName *QTN =
5816    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5817  if (!QTN) {
5818    QTN = new (*this, llvm::alignOf<QualifiedTemplateName>())
5819        QualifiedTemplateName(NNS, TemplateKeyword, Template);
5820    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
5821  }
5822
5823  return TemplateName(QTN);
5824}
5825
5826/// \brief Retrieve the template name that represents a dependent
5827/// template name such as \c MetaFun::template apply.
5828TemplateName
5829ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
5830                                     const IdentifierInfo *Name) const {
5831  assert((!NNS || NNS->isDependent()) &&
5832         "Nested name specifier must be dependent");
5833
5834  llvm::FoldingSetNodeID ID;
5835  DependentTemplateName::Profile(ID, NNS, Name);
5836
5837  void *InsertPos = 0;
5838  DependentTemplateName *QTN =
5839    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5840
5841  if (QTN)
5842    return TemplateName(QTN);
5843
5844  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
5845  if (CanonNNS == NNS) {
5846    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
5847        DependentTemplateName(NNS, Name);
5848  } else {
5849    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
5850    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
5851        DependentTemplateName(NNS, Name, Canon);
5852    DependentTemplateName *CheckQTN =
5853      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5854    assert(!CheckQTN && "Dependent type name canonicalization broken");
5855    (void)CheckQTN;
5856  }
5857
5858  DependentTemplateNames.InsertNode(QTN, InsertPos);
5859  return TemplateName(QTN);
5860}
5861
5862/// \brief Retrieve the template name that represents a dependent
5863/// template name such as \c MetaFun::template operator+.
5864TemplateName
5865ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
5866                                     OverloadedOperatorKind Operator) const {
5867  assert((!NNS || NNS->isDependent()) &&
5868         "Nested name specifier must be dependent");
5869
5870  llvm::FoldingSetNodeID ID;
5871  DependentTemplateName::Profile(ID, NNS, Operator);
5872
5873  void *InsertPos = 0;
5874  DependentTemplateName *QTN
5875    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5876
5877  if (QTN)
5878    return TemplateName(QTN);
5879
5880  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
5881  if (CanonNNS == NNS) {
5882    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
5883        DependentTemplateName(NNS, Operator);
5884  } else {
5885    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
5886    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
5887        DependentTemplateName(NNS, Operator, Canon);
5888
5889    DependentTemplateName *CheckQTN
5890      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
5891    assert(!CheckQTN && "Dependent template name canonicalization broken");
5892    (void)CheckQTN;
5893  }
5894
5895  DependentTemplateNames.InsertNode(QTN, InsertPos);
5896  return TemplateName(QTN);
5897}
5898
5899TemplateName
5900ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
5901                                         TemplateName replacement) const {
5902  llvm::FoldingSetNodeID ID;
5903  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
5904
5905  void *insertPos = 0;
5906  SubstTemplateTemplateParmStorage *subst
5907    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
5908
5909  if (!subst) {
5910    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
5911    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
5912  }
5913
5914  return TemplateName(subst);
5915}
5916
5917TemplateName
5918ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
5919                                       const TemplateArgument &ArgPack) const {
5920  ASTContext &Self = const_cast<ASTContext &>(*this);
5921  llvm::FoldingSetNodeID ID;
5922  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
5923
5924  void *InsertPos = 0;
5925  SubstTemplateTemplateParmPackStorage *Subst
5926    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
5927
5928  if (!Subst) {
5929    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
5930                                                           ArgPack.pack_size(),
5931                                                         ArgPack.pack_begin());
5932    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
5933  }
5934
5935  return TemplateName(Subst);
5936}
5937
5938/// getFromTargetType - Given one of the integer types provided by
5939/// TargetInfo, produce the corresponding type. The unsigned @p Type
5940/// is actually a value of type @c TargetInfo::IntType.
5941CanQualType ASTContext::getFromTargetType(unsigned Type) const {
5942  switch (Type) {
5943  case TargetInfo::NoInt: return CanQualType();
5944  case TargetInfo::SignedShort: return ShortTy;
5945  case TargetInfo::UnsignedShort: return UnsignedShortTy;
5946  case TargetInfo::SignedInt: return IntTy;
5947  case TargetInfo::UnsignedInt: return UnsignedIntTy;
5948  case TargetInfo::SignedLong: return LongTy;
5949  case TargetInfo::UnsignedLong: return UnsignedLongTy;
5950  case TargetInfo::SignedLongLong: return LongLongTy;
5951  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
5952  }
5953
5954  llvm_unreachable("Unhandled TargetInfo::IntType value");
5955}
5956
5957//===----------------------------------------------------------------------===//
5958//                        Type Predicates.
5959//===----------------------------------------------------------------------===//
5960
5961/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
5962/// garbage collection attribute.
5963///
5964Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
5965  if (getLangOpts().getGC() == LangOptions::NonGC)
5966    return Qualifiers::GCNone;
5967
5968  assert(getLangOpts().ObjC1);
5969  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
5970
5971  // Default behaviour under objective-C's gc is for ObjC pointers
5972  // (or pointers to them) be treated as though they were declared
5973  // as __strong.
5974  if (GCAttrs == Qualifiers::GCNone) {
5975    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
5976      return Qualifiers::Strong;
5977    else if (Ty->isPointerType())
5978      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
5979  } else {
5980    // It's not valid to set GC attributes on anything that isn't a
5981    // pointer.
5982#ifndef NDEBUG
5983    QualType CT = Ty->getCanonicalTypeInternal();
5984    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
5985      CT = AT->getElementType();
5986    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
5987#endif
5988  }
5989  return GCAttrs;
5990}
5991
5992//===----------------------------------------------------------------------===//
5993//                        Type Compatibility Testing
5994//===----------------------------------------------------------------------===//
5995
5996/// areCompatVectorTypes - Return true if the two specified vector types are
5997/// compatible.
5998static bool areCompatVectorTypes(const VectorType *LHS,
5999                                 const VectorType *RHS) {
6000  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
6001  return LHS->getElementType() == RHS->getElementType() &&
6002         LHS->getNumElements() == RHS->getNumElements();
6003}
6004
6005bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
6006                                          QualType SecondVec) {
6007  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
6008  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
6009
6010  if (hasSameUnqualifiedType(FirstVec, SecondVec))
6011    return true;
6012
6013  // Treat Neon vector types and most AltiVec vector types as if they are the
6014  // equivalent GCC vector types.
6015  const VectorType *First = FirstVec->getAs<VectorType>();
6016  const VectorType *Second = SecondVec->getAs<VectorType>();
6017  if (First->getNumElements() == Second->getNumElements() &&
6018      hasSameType(First->getElementType(), Second->getElementType()) &&
6019      First->getVectorKind() != VectorType::AltiVecPixel &&
6020      First->getVectorKind() != VectorType::AltiVecBool &&
6021      Second->getVectorKind() != VectorType::AltiVecPixel &&
6022      Second->getVectorKind() != VectorType::AltiVecBool)
6023    return true;
6024
6025  return false;
6026}
6027
6028//===----------------------------------------------------------------------===//
6029// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
6030//===----------------------------------------------------------------------===//
6031
6032/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
6033/// inheritance hierarchy of 'rProto'.
6034bool
6035ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
6036                                           ObjCProtocolDecl *rProto) const {
6037  if (declaresSameEntity(lProto, rProto))
6038    return true;
6039  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
6040       E = rProto->protocol_end(); PI != E; ++PI)
6041    if (ProtocolCompatibleWithProtocol(lProto, *PI))
6042      return true;
6043  return false;
6044}
6045
6046/// QualifiedIdConformsQualifiedId - compare id<pr,...> with id<pr1,...>
6047/// return true if lhs's protocols conform to rhs's protocol; false
6048/// otherwise.
6049bool ASTContext::QualifiedIdConformsQualifiedId(QualType lhs, QualType rhs) {
6050  if (lhs->isObjCQualifiedIdType() && rhs->isObjCQualifiedIdType())
6051    return ObjCQualifiedIdTypesAreCompatible(lhs, rhs, false);
6052  return false;
6053}
6054
6055/// ObjCQualifiedClassTypesAreCompatible - compare  Class<pr,...> and
6056/// Class<pr1, ...>.
6057bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
6058                                                      QualType rhs) {
6059  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
6060  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
6061  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
6062
6063  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
6064       E = lhsQID->qual_end(); I != E; ++I) {
6065    bool match = false;
6066    ObjCProtocolDecl *lhsProto = *I;
6067    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
6068         E = rhsOPT->qual_end(); J != E; ++J) {
6069      ObjCProtocolDecl *rhsProto = *J;
6070      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
6071        match = true;
6072        break;
6073      }
6074    }
6075    if (!match)
6076      return false;
6077  }
6078  return true;
6079}
6080
6081/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
6082/// ObjCQualifiedIDType.
6083bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
6084                                                   bool compare) {
6085  // Allow id<P..> and an 'id' or void* type in all cases.
6086  if (lhs->isVoidPointerType() ||
6087      lhs->isObjCIdType() || lhs->isObjCClassType())
6088    return true;
6089  else if (rhs->isVoidPointerType() ||
6090           rhs->isObjCIdType() || rhs->isObjCClassType())
6091    return true;
6092
6093  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
6094    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
6095
6096    if (!rhsOPT) return false;
6097
6098    if (rhsOPT->qual_empty()) {
6099      // If the RHS is a unqualified interface pointer "NSString*",
6100      // make sure we check the class hierarchy.
6101      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
6102        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
6103             E = lhsQID->qual_end(); I != E; ++I) {
6104          // when comparing an id<P> on lhs with a static type on rhs,
6105          // see if static class implements all of id's protocols, directly or
6106          // through its super class and categories.
6107          if (!rhsID->ClassImplementsProtocol(*I, true))
6108            return false;
6109        }
6110      }
6111      // If there are no qualifiers and no interface, we have an 'id'.
6112      return true;
6113    }
6114    // Both the right and left sides have qualifiers.
6115    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
6116         E = lhsQID->qual_end(); I != E; ++I) {
6117      ObjCProtocolDecl *lhsProto = *I;
6118      bool match = false;
6119
6120      // when comparing an id<P> on lhs with a static type on rhs,
6121      // see if static class implements all of id's protocols, directly or
6122      // through its super class and categories.
6123      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
6124           E = rhsOPT->qual_end(); J != E; ++J) {
6125        ObjCProtocolDecl *rhsProto = *J;
6126        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6127            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6128          match = true;
6129          break;
6130        }
6131      }
6132      // If the RHS is a qualified interface pointer "NSString<P>*",
6133      // make sure we check the class hierarchy.
6134      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
6135        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
6136             E = lhsQID->qual_end(); I != E; ++I) {
6137          // when comparing an id<P> on lhs with a static type on rhs,
6138          // see if static class implements all of id's protocols, directly or
6139          // through its super class and categories.
6140          if (rhsID->ClassImplementsProtocol(*I, true)) {
6141            match = true;
6142            break;
6143          }
6144        }
6145      }
6146      if (!match)
6147        return false;
6148    }
6149
6150    return true;
6151  }
6152
6153  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
6154  assert(rhsQID && "One of the LHS/RHS should be id<x>");
6155
6156  if (const ObjCObjectPointerType *lhsOPT =
6157        lhs->getAsObjCInterfacePointerType()) {
6158    // If both the right and left sides have qualifiers.
6159    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
6160         E = lhsOPT->qual_end(); I != E; ++I) {
6161      ObjCProtocolDecl *lhsProto = *I;
6162      bool match = false;
6163
6164      // when comparing an id<P> on rhs with a static type on lhs,
6165      // see if static class implements all of id's protocols, directly or
6166      // through its super class and categories.
6167      // First, lhs protocols in the qualifier list must be found, direct
6168      // or indirect in rhs's qualifier list or it is a mismatch.
6169      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
6170           E = rhsQID->qual_end(); J != E; ++J) {
6171        ObjCProtocolDecl *rhsProto = *J;
6172        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6173            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6174          match = true;
6175          break;
6176        }
6177      }
6178      if (!match)
6179        return false;
6180    }
6181
6182    // Static class's protocols, or its super class or category protocols
6183    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
6184    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
6185      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
6186      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
6187      // This is rather dubious but matches gcc's behavior. If lhs has
6188      // no type qualifier and its class has no static protocol(s)
6189      // assume that it is mismatch.
6190      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
6191        return false;
6192      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
6193           LHSInheritedProtocols.begin(),
6194           E = LHSInheritedProtocols.end(); I != E; ++I) {
6195        bool match = false;
6196        ObjCProtocolDecl *lhsProto = (*I);
6197        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
6198             E = rhsQID->qual_end(); J != E; ++J) {
6199          ObjCProtocolDecl *rhsProto = *J;
6200          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6201              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6202            match = true;
6203            break;
6204          }
6205        }
6206        if (!match)
6207          return false;
6208      }
6209    }
6210    return true;
6211  }
6212  return false;
6213}
6214
6215/// canAssignObjCInterfaces - Return true if the two interface types are
6216/// compatible for assignment from RHS to LHS.  This handles validation of any
6217/// protocol qualifiers on the LHS or RHS.
6218///
6219bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
6220                                         const ObjCObjectPointerType *RHSOPT) {
6221  const ObjCObjectType* LHS = LHSOPT->getObjectType();
6222  const ObjCObjectType* RHS = RHSOPT->getObjectType();
6223
6224  // If either type represents the built-in 'id' or 'Class' types, return true.
6225  if (LHS->isObjCUnqualifiedIdOrClass() ||
6226      RHS->isObjCUnqualifiedIdOrClass())
6227    return true;
6228
6229  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
6230    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
6231                                             QualType(RHSOPT,0),
6232                                             false);
6233
6234  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
6235    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
6236                                                QualType(RHSOPT,0));
6237
6238  // If we have 2 user-defined types, fall into that path.
6239  if (LHS->getInterface() && RHS->getInterface())
6240    return canAssignObjCInterfaces(LHS, RHS);
6241
6242  return false;
6243}
6244
6245/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
6246/// for providing type-safety for objective-c pointers used to pass/return
6247/// arguments in block literals. When passed as arguments, passing 'A*' where
6248/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
6249/// not OK. For the return type, the opposite is not OK.
6250bool ASTContext::canAssignObjCInterfacesInBlockPointer(
6251                                         const ObjCObjectPointerType *LHSOPT,
6252                                         const ObjCObjectPointerType *RHSOPT,
6253                                         bool BlockReturnType) {
6254  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
6255    return true;
6256
6257  if (LHSOPT->isObjCBuiltinType()) {
6258    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
6259  }
6260
6261  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
6262    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
6263                                             QualType(RHSOPT,0),
6264                                             false);
6265
6266  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
6267  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
6268  if (LHS && RHS)  { // We have 2 user-defined types.
6269    if (LHS != RHS) {
6270      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
6271        return BlockReturnType;
6272      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
6273        return !BlockReturnType;
6274    }
6275    else
6276      return true;
6277  }
6278  return false;
6279}
6280
6281/// getIntersectionOfProtocols - This routine finds the intersection of set
6282/// of protocols inherited from two distinct objective-c pointer objects.
6283/// It is used to build composite qualifier list of the composite type of
6284/// the conditional expression involving two objective-c pointer objects.
6285static
6286void getIntersectionOfProtocols(ASTContext &Context,
6287                                const ObjCObjectPointerType *LHSOPT,
6288                                const ObjCObjectPointerType *RHSOPT,
6289      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
6290
6291  const ObjCObjectType* LHS = LHSOPT->getObjectType();
6292  const ObjCObjectType* RHS = RHSOPT->getObjectType();
6293  assert(LHS->getInterface() && "LHS must have an interface base");
6294  assert(RHS->getInterface() && "RHS must have an interface base");
6295
6296  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
6297  unsigned LHSNumProtocols = LHS->getNumProtocols();
6298  if (LHSNumProtocols > 0)
6299    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
6300  else {
6301    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
6302    Context.CollectInheritedProtocols(LHS->getInterface(),
6303                                      LHSInheritedProtocols);
6304    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
6305                                LHSInheritedProtocols.end());
6306  }
6307
6308  unsigned RHSNumProtocols = RHS->getNumProtocols();
6309  if (RHSNumProtocols > 0) {
6310    ObjCProtocolDecl **RHSProtocols =
6311      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
6312    for (unsigned i = 0; i < RHSNumProtocols; ++i)
6313      if (InheritedProtocolSet.count(RHSProtocols[i]))
6314        IntersectionOfProtocols.push_back(RHSProtocols[i]);
6315  } else {
6316    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
6317    Context.CollectInheritedProtocols(RHS->getInterface(),
6318                                      RHSInheritedProtocols);
6319    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
6320         RHSInheritedProtocols.begin(),
6321         E = RHSInheritedProtocols.end(); I != E; ++I)
6322      if (InheritedProtocolSet.count((*I)))
6323        IntersectionOfProtocols.push_back((*I));
6324  }
6325}
6326
6327/// areCommonBaseCompatible - Returns common base class of the two classes if
6328/// one found. Note that this is O'2 algorithm. But it will be called as the
6329/// last type comparison in a ?-exp of ObjC pointer types before a
6330/// warning is issued. So, its invokation is extremely rare.
6331QualType ASTContext::areCommonBaseCompatible(
6332                                          const ObjCObjectPointerType *Lptr,
6333                                          const ObjCObjectPointerType *Rptr) {
6334  const ObjCObjectType *LHS = Lptr->getObjectType();
6335  const ObjCObjectType *RHS = Rptr->getObjectType();
6336  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
6337  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
6338  if (!LDecl || !RDecl || (declaresSameEntity(LDecl, RDecl)))
6339    return QualType();
6340
6341  do {
6342    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
6343    if (canAssignObjCInterfaces(LHS, RHS)) {
6344      SmallVector<ObjCProtocolDecl *, 8> Protocols;
6345      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
6346
6347      QualType Result = QualType(LHS, 0);
6348      if (!Protocols.empty())
6349        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
6350      Result = getObjCObjectPointerType(Result);
6351      return Result;
6352    }
6353  } while ((LDecl = LDecl->getSuperClass()));
6354
6355  return QualType();
6356}
6357
6358bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
6359                                         const ObjCObjectType *RHS) {
6360  assert(LHS->getInterface() && "LHS is not an interface type");
6361  assert(RHS->getInterface() && "RHS is not an interface type");
6362
6363  // Verify that the base decls are compatible: the RHS must be a subclass of
6364  // the LHS.
6365  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
6366    return false;
6367
6368  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
6369  // protocol qualified at all, then we are good.
6370  if (LHS->getNumProtocols() == 0)
6371    return true;
6372
6373  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't,
6374  // more detailed analysis is required.
6375  if (RHS->getNumProtocols() == 0) {
6376    // OK, if LHS is a superclass of RHS *and*
6377    // this superclass is assignment compatible with LHS.
6378    // false otherwise.
6379    bool IsSuperClass =
6380      LHS->getInterface()->isSuperClassOf(RHS->getInterface());
6381    if (IsSuperClass) {
6382      // OK if conversion of LHS to SuperClass results in narrowing of types
6383      // ; i.e., SuperClass may implement at least one of the protocols
6384      // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
6385      // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
6386      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
6387      CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
6388      // If super class has no protocols, it is not a match.
6389      if (SuperClassInheritedProtocols.empty())
6390        return false;
6391
6392      for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
6393           LHSPE = LHS->qual_end();
6394           LHSPI != LHSPE; LHSPI++) {
6395        bool SuperImplementsProtocol = false;
6396        ObjCProtocolDecl *LHSProto = (*LHSPI);
6397
6398        for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
6399             SuperClassInheritedProtocols.begin(),
6400             E = SuperClassInheritedProtocols.end(); I != E; ++I) {
6401          ObjCProtocolDecl *SuperClassProto = (*I);
6402          if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
6403            SuperImplementsProtocol = true;
6404            break;
6405          }
6406        }
6407        if (!SuperImplementsProtocol)
6408          return false;
6409      }
6410      return true;
6411    }
6412    return false;
6413  }
6414
6415  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
6416                                     LHSPE = LHS->qual_end();
6417       LHSPI != LHSPE; LHSPI++) {
6418    bool RHSImplementsProtocol = false;
6419
6420    // If the RHS doesn't implement the protocol on the left, the types
6421    // are incompatible.
6422    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
6423                                       RHSPE = RHS->qual_end();
6424         RHSPI != RHSPE; RHSPI++) {
6425      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
6426        RHSImplementsProtocol = true;
6427        break;
6428      }
6429    }
6430    // FIXME: For better diagnostics, consider passing back the protocol name.
6431    if (!RHSImplementsProtocol)
6432      return false;
6433  }
6434  // The RHS implements all protocols listed on the LHS.
6435  return true;
6436}
6437
6438bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
6439  // get the "pointed to" types
6440  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
6441  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
6442
6443  if (!LHSOPT || !RHSOPT)
6444    return false;
6445
6446  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
6447         canAssignObjCInterfaces(RHSOPT, LHSOPT);
6448}
6449
6450bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
6451  return canAssignObjCInterfaces(
6452                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
6453                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
6454}
6455
6456/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
6457/// both shall have the identically qualified version of a compatible type.
6458/// C99 6.2.7p1: Two types have compatible types if their types are the
6459/// same. See 6.7.[2,3,5] for additional rules.
6460bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
6461                                    bool CompareUnqualified) {
6462  if (getLangOpts().CPlusPlus)
6463    return hasSameType(LHS, RHS);
6464
6465  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
6466}
6467
6468bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
6469  return typesAreCompatible(LHS, RHS);
6470}
6471
6472bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
6473  return !mergeTypes(LHS, RHS, true).isNull();
6474}
6475
6476/// mergeTransparentUnionType - if T is a transparent union type and a member
6477/// of T is compatible with SubType, return the merged type, else return
6478/// QualType()
6479QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
6480                                               bool OfBlockPointer,
6481                                               bool Unqualified) {
6482  if (const RecordType *UT = T->getAsUnionType()) {
6483    RecordDecl *UD = UT->getDecl();
6484    if (UD->hasAttr<TransparentUnionAttr>()) {
6485      for (RecordDecl::field_iterator it = UD->field_begin(),
6486           itend = UD->field_end(); it != itend; ++it) {
6487        QualType ET = it->getType().getUnqualifiedType();
6488        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
6489        if (!MT.isNull())
6490          return MT;
6491      }
6492    }
6493  }
6494
6495  return QualType();
6496}
6497
6498/// mergeFunctionArgumentTypes - merge two types which appear as function
6499/// argument types
6500QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
6501                                                bool OfBlockPointer,
6502                                                bool Unqualified) {
6503  // GNU extension: two types are compatible if they appear as a function
6504  // argument, one of the types is a transparent union type and the other
6505  // type is compatible with a union member
6506  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
6507                                              Unqualified);
6508  if (!lmerge.isNull())
6509    return lmerge;
6510
6511  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
6512                                              Unqualified);
6513  if (!rmerge.isNull())
6514    return rmerge;
6515
6516  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
6517}
6518
6519QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
6520                                        bool OfBlockPointer,
6521                                        bool Unqualified) {
6522  const FunctionType *lbase = lhs->getAs<FunctionType>();
6523  const FunctionType *rbase = rhs->getAs<FunctionType>();
6524  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
6525  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
6526  bool allLTypes = true;
6527  bool allRTypes = true;
6528
6529  // Check return type
6530  QualType retType;
6531  if (OfBlockPointer) {
6532    QualType RHS = rbase->getResultType();
6533    QualType LHS = lbase->getResultType();
6534    bool UnqualifiedResult = Unqualified;
6535    if (!UnqualifiedResult)
6536      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
6537    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
6538  }
6539  else
6540    retType = mergeTypes(lbase->getResultType(), rbase->getResultType(), false,
6541                         Unqualified);
6542  if (retType.isNull()) return QualType();
6543
6544  if (Unqualified)
6545    retType = retType.getUnqualifiedType();
6546
6547  CanQualType LRetType = getCanonicalType(lbase->getResultType());
6548  CanQualType RRetType = getCanonicalType(rbase->getResultType());
6549  if (Unqualified) {
6550    LRetType = LRetType.getUnqualifiedType();
6551    RRetType = RRetType.getUnqualifiedType();
6552  }
6553
6554  if (getCanonicalType(retType) != LRetType)
6555    allLTypes = false;
6556  if (getCanonicalType(retType) != RRetType)
6557    allRTypes = false;
6558
6559  // FIXME: double check this
6560  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
6561  //                           rbase->getRegParmAttr() != 0 &&
6562  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
6563  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
6564  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
6565
6566  // Compatible functions must have compatible calling conventions
6567  if (!isSameCallConv(lbaseInfo.getCC(), rbaseInfo.getCC()))
6568    return QualType();
6569
6570  // Regparm is part of the calling convention.
6571  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
6572    return QualType();
6573  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
6574    return QualType();
6575
6576  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
6577    return QualType();
6578
6579  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
6580  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
6581
6582  if (lbaseInfo.getNoReturn() != NoReturn)
6583    allLTypes = false;
6584  if (rbaseInfo.getNoReturn() != NoReturn)
6585    allRTypes = false;
6586
6587  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
6588
6589  if (lproto && rproto) { // two C99 style function prototypes
6590    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
6591           "C++ shouldn't be here");
6592    unsigned lproto_nargs = lproto->getNumArgs();
6593    unsigned rproto_nargs = rproto->getNumArgs();
6594
6595    // Compatible functions must have the same number of arguments
6596    if (lproto_nargs != rproto_nargs)
6597      return QualType();
6598
6599    // Variadic and non-variadic functions aren't compatible
6600    if (lproto->isVariadic() != rproto->isVariadic())
6601      return QualType();
6602
6603    if (lproto->getTypeQuals() != rproto->getTypeQuals())
6604      return QualType();
6605
6606    if (LangOpts.ObjCAutoRefCount &&
6607        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
6608      return QualType();
6609
6610    // Check argument compatibility
6611    SmallVector<QualType, 10> types;
6612    for (unsigned i = 0; i < lproto_nargs; i++) {
6613      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
6614      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
6615      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
6616                                                    OfBlockPointer,
6617                                                    Unqualified);
6618      if (argtype.isNull()) return QualType();
6619
6620      if (Unqualified)
6621        argtype = argtype.getUnqualifiedType();
6622
6623      types.push_back(argtype);
6624      if (Unqualified) {
6625        largtype = largtype.getUnqualifiedType();
6626        rargtype = rargtype.getUnqualifiedType();
6627      }
6628
6629      if (getCanonicalType(argtype) != getCanonicalType(largtype))
6630        allLTypes = false;
6631      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
6632        allRTypes = false;
6633    }
6634
6635    if (allLTypes) return lhs;
6636    if (allRTypes) return rhs;
6637
6638    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
6639    EPI.ExtInfo = einfo;
6640    return getFunctionType(retType, types.begin(), types.size(), EPI);
6641  }
6642
6643  if (lproto) allRTypes = false;
6644  if (rproto) allLTypes = false;
6645
6646  const FunctionProtoType *proto = lproto ? lproto : rproto;
6647  if (proto) {
6648    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
6649    if (proto->isVariadic()) return QualType();
6650    // Check that the types are compatible with the types that
6651    // would result from default argument promotions (C99 6.7.5.3p15).
6652    // The only types actually affected are promotable integer
6653    // types and floats, which would be passed as a different
6654    // type depending on whether the prototype is visible.
6655    unsigned proto_nargs = proto->getNumArgs();
6656    for (unsigned i = 0; i < proto_nargs; ++i) {
6657      QualType argTy = proto->getArgType(i);
6658
6659      // Look at the converted type of enum types, since that is the type used
6660      // to pass enum values.
6661      if (const EnumType *Enum = argTy->getAs<EnumType>()) {
6662        argTy = Enum->getDecl()->getIntegerType();
6663        if (argTy.isNull())
6664          return QualType();
6665      }
6666
6667      if (argTy->isPromotableIntegerType() ||
6668          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
6669        return QualType();
6670    }
6671
6672    if (allLTypes) return lhs;
6673    if (allRTypes) return rhs;
6674
6675    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
6676    EPI.ExtInfo = einfo;
6677    return getFunctionType(retType, proto->arg_type_begin(),
6678                           proto->getNumArgs(), EPI);
6679  }
6680
6681  if (allLTypes) return lhs;
6682  if (allRTypes) return rhs;
6683  return getFunctionNoProtoType(retType, einfo);
6684}
6685
6686QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
6687                                bool OfBlockPointer,
6688                                bool Unqualified, bool BlockReturnType) {
6689  // C++ [expr]: If an expression initially has the type "reference to T", the
6690  // type is adjusted to "T" prior to any further analysis, the expression
6691  // designates the object or function denoted by the reference, and the
6692  // expression is an lvalue unless the reference is an rvalue reference and
6693  // the expression is a function call (possibly inside parentheses).
6694  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
6695  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
6696
6697  if (Unqualified) {
6698    LHS = LHS.getUnqualifiedType();
6699    RHS = RHS.getUnqualifiedType();
6700  }
6701
6702  QualType LHSCan = getCanonicalType(LHS),
6703           RHSCan = getCanonicalType(RHS);
6704
6705  // If two types are identical, they are compatible.
6706  if (LHSCan == RHSCan)
6707    return LHS;
6708
6709  // If the qualifiers are different, the types aren't compatible... mostly.
6710  Qualifiers LQuals = LHSCan.getLocalQualifiers();
6711  Qualifiers RQuals = RHSCan.getLocalQualifiers();
6712  if (LQuals != RQuals) {
6713    // If any of these qualifiers are different, we have a type
6714    // mismatch.
6715    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
6716        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
6717        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
6718      return QualType();
6719
6720    // Exactly one GC qualifier difference is allowed: __strong is
6721    // okay if the other type has no GC qualifier but is an Objective
6722    // C object pointer (i.e. implicitly strong by default).  We fix
6723    // this by pretending that the unqualified type was actually
6724    // qualified __strong.
6725    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
6726    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
6727    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
6728
6729    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
6730      return QualType();
6731
6732    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
6733      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
6734    }
6735    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
6736      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
6737    }
6738    return QualType();
6739  }
6740
6741  // Okay, qualifiers are equal.
6742
6743  Type::TypeClass LHSClass = LHSCan->getTypeClass();
6744  Type::TypeClass RHSClass = RHSCan->getTypeClass();
6745
6746  // We want to consider the two function types to be the same for these
6747  // comparisons, just force one to the other.
6748  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
6749  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
6750
6751  // Same as above for arrays
6752  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
6753    LHSClass = Type::ConstantArray;
6754  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
6755    RHSClass = Type::ConstantArray;
6756
6757  // ObjCInterfaces are just specialized ObjCObjects.
6758  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
6759  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
6760
6761  // Canonicalize ExtVector -> Vector.
6762  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
6763  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
6764
6765  // If the canonical type classes don't match.
6766  if (LHSClass != RHSClass) {
6767    // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
6768    // a signed integer type, or an unsigned integer type.
6769    // Compatibility is based on the underlying type, not the promotion
6770    // type.
6771    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
6772      QualType TINT = ETy->getDecl()->getIntegerType();
6773      if (!TINT.isNull() && hasSameType(TINT, RHSCan.getUnqualifiedType()))
6774        return RHS;
6775    }
6776    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
6777      QualType TINT = ETy->getDecl()->getIntegerType();
6778      if (!TINT.isNull() && hasSameType(TINT, LHSCan.getUnqualifiedType()))
6779        return LHS;
6780    }
6781    // allow block pointer type to match an 'id' type.
6782    if (OfBlockPointer && !BlockReturnType) {
6783       if (LHS->isObjCIdType() && RHS->isBlockPointerType())
6784         return LHS;
6785      if (RHS->isObjCIdType() && LHS->isBlockPointerType())
6786        return RHS;
6787    }
6788
6789    return QualType();
6790  }
6791
6792  // The canonical type classes match.
6793  switch (LHSClass) {
6794#define TYPE(Class, Base)
6795#define ABSTRACT_TYPE(Class, Base)
6796#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
6797#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
6798#define DEPENDENT_TYPE(Class, Base) case Type::Class:
6799#include "clang/AST/TypeNodes.def"
6800    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
6801
6802  case Type::LValueReference:
6803  case Type::RValueReference:
6804  case Type::MemberPointer:
6805    llvm_unreachable("C++ should never be in mergeTypes");
6806
6807  case Type::ObjCInterface:
6808  case Type::IncompleteArray:
6809  case Type::VariableArray:
6810  case Type::FunctionProto:
6811  case Type::ExtVector:
6812    llvm_unreachable("Types are eliminated above");
6813
6814  case Type::Pointer:
6815  {
6816    // Merge two pointer types, while trying to preserve typedef info
6817    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
6818    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
6819    if (Unqualified) {
6820      LHSPointee = LHSPointee.getUnqualifiedType();
6821      RHSPointee = RHSPointee.getUnqualifiedType();
6822    }
6823    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
6824                                     Unqualified);
6825    if (ResultType.isNull()) return QualType();
6826    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
6827      return LHS;
6828    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
6829      return RHS;
6830    return getPointerType(ResultType);
6831  }
6832  case Type::BlockPointer:
6833  {
6834    // Merge two block pointer types, while trying to preserve typedef info
6835    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
6836    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
6837    if (Unqualified) {
6838      LHSPointee = LHSPointee.getUnqualifiedType();
6839      RHSPointee = RHSPointee.getUnqualifiedType();
6840    }
6841    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
6842                                     Unqualified);
6843    if (ResultType.isNull()) return QualType();
6844    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
6845      return LHS;
6846    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
6847      return RHS;
6848    return getBlockPointerType(ResultType);
6849  }
6850  case Type::Atomic:
6851  {
6852    // Merge two pointer types, while trying to preserve typedef info
6853    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
6854    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
6855    if (Unqualified) {
6856      LHSValue = LHSValue.getUnqualifiedType();
6857      RHSValue = RHSValue.getUnqualifiedType();
6858    }
6859    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
6860                                     Unqualified);
6861    if (ResultType.isNull()) return QualType();
6862    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
6863      return LHS;
6864    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
6865      return RHS;
6866    return getAtomicType(ResultType);
6867  }
6868  case Type::ConstantArray:
6869  {
6870    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
6871    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
6872    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
6873      return QualType();
6874
6875    QualType LHSElem = getAsArrayType(LHS)->getElementType();
6876    QualType RHSElem = getAsArrayType(RHS)->getElementType();
6877    if (Unqualified) {
6878      LHSElem = LHSElem.getUnqualifiedType();
6879      RHSElem = RHSElem.getUnqualifiedType();
6880    }
6881
6882    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
6883    if (ResultType.isNull()) return QualType();
6884    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
6885      return LHS;
6886    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
6887      return RHS;
6888    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
6889                                          ArrayType::ArraySizeModifier(), 0);
6890    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
6891                                          ArrayType::ArraySizeModifier(), 0);
6892    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
6893    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
6894    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
6895      return LHS;
6896    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
6897      return RHS;
6898    if (LVAT) {
6899      // FIXME: This isn't correct! But tricky to implement because
6900      // the array's size has to be the size of LHS, but the type
6901      // has to be different.
6902      return LHS;
6903    }
6904    if (RVAT) {
6905      // FIXME: This isn't correct! But tricky to implement because
6906      // the array's size has to be the size of RHS, but the type
6907      // has to be different.
6908      return RHS;
6909    }
6910    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
6911    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
6912    return getIncompleteArrayType(ResultType,
6913                                  ArrayType::ArraySizeModifier(), 0);
6914  }
6915  case Type::FunctionNoProto:
6916    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
6917  case Type::Record:
6918  case Type::Enum:
6919    return QualType();
6920  case Type::Builtin:
6921    // Only exactly equal builtin types are compatible, which is tested above.
6922    return QualType();
6923  case Type::Complex:
6924    // Distinct complex types are incompatible.
6925    return QualType();
6926  case Type::Vector:
6927    // FIXME: The merged type should be an ExtVector!
6928    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
6929                             RHSCan->getAs<VectorType>()))
6930      return LHS;
6931    return QualType();
6932  case Type::ObjCObject: {
6933    // Check if the types are assignment compatible.
6934    // FIXME: This should be type compatibility, e.g. whether
6935    // "LHS x; RHS x;" at global scope is legal.
6936    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
6937    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
6938    if (canAssignObjCInterfaces(LHSIface, RHSIface))
6939      return LHS;
6940
6941    return QualType();
6942  }
6943  case Type::ObjCObjectPointer: {
6944    if (OfBlockPointer) {
6945      if (canAssignObjCInterfacesInBlockPointer(
6946                                          LHS->getAs<ObjCObjectPointerType>(),
6947                                          RHS->getAs<ObjCObjectPointerType>(),
6948                                          BlockReturnType))
6949        return LHS;
6950      return QualType();
6951    }
6952    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
6953                                RHS->getAs<ObjCObjectPointerType>()))
6954      return LHS;
6955
6956    return QualType();
6957  }
6958  }
6959
6960  llvm_unreachable("Invalid Type::Class!");
6961}
6962
6963bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
6964                   const FunctionProtoType *FromFunctionType,
6965                   const FunctionProtoType *ToFunctionType) {
6966  if (FromFunctionType->hasAnyConsumedArgs() !=
6967      ToFunctionType->hasAnyConsumedArgs())
6968    return false;
6969  FunctionProtoType::ExtProtoInfo FromEPI =
6970    FromFunctionType->getExtProtoInfo();
6971  FunctionProtoType::ExtProtoInfo ToEPI =
6972    ToFunctionType->getExtProtoInfo();
6973  if (FromEPI.ConsumedArguments && ToEPI.ConsumedArguments)
6974    for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs();
6975         ArgIdx != NumArgs; ++ArgIdx)  {
6976      if (FromEPI.ConsumedArguments[ArgIdx] !=
6977          ToEPI.ConsumedArguments[ArgIdx])
6978        return false;
6979    }
6980  return true;
6981}
6982
6983/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
6984/// 'RHS' attributes and returns the merged version; including for function
6985/// return types.
6986QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
6987  QualType LHSCan = getCanonicalType(LHS),
6988  RHSCan = getCanonicalType(RHS);
6989  // If two types are identical, they are compatible.
6990  if (LHSCan == RHSCan)
6991    return LHS;
6992  if (RHSCan->isFunctionType()) {
6993    if (!LHSCan->isFunctionType())
6994      return QualType();
6995    QualType OldReturnType =
6996      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
6997    QualType NewReturnType =
6998      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
6999    QualType ResReturnType =
7000      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
7001    if (ResReturnType.isNull())
7002      return QualType();
7003    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
7004      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
7005      // In either case, use OldReturnType to build the new function type.
7006      const FunctionType *F = LHS->getAs<FunctionType>();
7007      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
7008        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
7009        EPI.ExtInfo = getFunctionExtInfo(LHS);
7010        QualType ResultType
7011          = getFunctionType(OldReturnType, FPT->arg_type_begin(),
7012                            FPT->getNumArgs(), EPI);
7013        return ResultType;
7014      }
7015    }
7016    return QualType();
7017  }
7018
7019  // If the qualifiers are different, the types can still be merged.
7020  Qualifiers LQuals = LHSCan.getLocalQualifiers();
7021  Qualifiers RQuals = RHSCan.getLocalQualifiers();
7022  if (LQuals != RQuals) {
7023    // If any of these qualifiers are different, we have a type mismatch.
7024    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
7025        LQuals.getAddressSpace() != RQuals.getAddressSpace())
7026      return QualType();
7027
7028    // Exactly one GC qualifier difference is allowed: __strong is
7029    // okay if the other type has no GC qualifier but is an Objective
7030    // C object pointer (i.e. implicitly strong by default).  We fix
7031    // this by pretending that the unqualified type was actually
7032    // qualified __strong.
7033    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
7034    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
7035    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
7036
7037    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
7038      return QualType();
7039
7040    if (GC_L == Qualifiers::Strong)
7041      return LHS;
7042    if (GC_R == Qualifiers::Strong)
7043      return RHS;
7044    return QualType();
7045  }
7046
7047  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
7048    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
7049    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
7050    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
7051    if (ResQT == LHSBaseQT)
7052      return LHS;
7053    if (ResQT == RHSBaseQT)
7054      return RHS;
7055  }
7056  return QualType();
7057}
7058
7059//===----------------------------------------------------------------------===//
7060//                         Integer Predicates
7061//===----------------------------------------------------------------------===//
7062
7063unsigned ASTContext::getIntWidth(QualType T) const {
7064  if (const EnumType *ET = dyn_cast<EnumType>(T))
7065    T = ET->getDecl()->getIntegerType();
7066  if (T->isBooleanType())
7067    return 1;
7068  // For builtin types, just use the standard type sizing method
7069  return (unsigned)getTypeSize(T);
7070}
7071
7072QualType ASTContext::getCorrespondingUnsignedType(QualType T) const {
7073  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
7074
7075  // Turn <4 x signed int> -> <4 x unsigned int>
7076  if (const VectorType *VTy = T->getAs<VectorType>())
7077    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
7078                         VTy->getNumElements(), VTy->getVectorKind());
7079
7080  // For enums, we return the unsigned version of the base type.
7081  if (const EnumType *ETy = T->getAs<EnumType>())
7082    T = ETy->getDecl()->getIntegerType();
7083
7084  const BuiltinType *BTy = T->getAs<BuiltinType>();
7085  assert(BTy && "Unexpected signed integer type");
7086  switch (BTy->getKind()) {
7087  case BuiltinType::Char_S:
7088  case BuiltinType::SChar:
7089    return UnsignedCharTy;
7090  case BuiltinType::Short:
7091    return UnsignedShortTy;
7092  case BuiltinType::Int:
7093    return UnsignedIntTy;
7094  case BuiltinType::Long:
7095    return UnsignedLongTy;
7096  case BuiltinType::LongLong:
7097    return UnsignedLongLongTy;
7098  case BuiltinType::Int128:
7099    return UnsignedInt128Ty;
7100  default:
7101    llvm_unreachable("Unexpected signed integer type");
7102  }
7103}
7104
7105ASTMutationListener::~ASTMutationListener() { }
7106
7107
7108//===----------------------------------------------------------------------===//
7109//                          Builtin Type Computation
7110//===----------------------------------------------------------------------===//
7111
7112/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
7113/// pointer over the consumed characters.  This returns the resultant type.  If
7114/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
7115/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
7116/// a vector of "i*".
7117///
7118/// RequiresICE is filled in on return to indicate whether the value is required
7119/// to be an Integer Constant Expression.
7120static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
7121                                  ASTContext::GetBuiltinTypeError &Error,
7122                                  bool &RequiresICE,
7123                                  bool AllowTypeModifiers) {
7124  // Modifiers.
7125  int HowLong = 0;
7126  bool Signed = false, Unsigned = false;
7127  RequiresICE = false;
7128
7129  // Read the prefixed modifiers first.
7130  bool Done = false;
7131  while (!Done) {
7132    switch (*Str++) {
7133    default: Done = true; --Str; break;
7134    case 'I':
7135      RequiresICE = true;
7136      break;
7137    case 'S':
7138      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
7139      assert(!Signed && "Can't use 'S' modifier multiple times!");
7140      Signed = true;
7141      break;
7142    case 'U':
7143      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
7144      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
7145      Unsigned = true;
7146      break;
7147    case 'L':
7148      assert(HowLong <= 2 && "Can't have LLLL modifier");
7149      ++HowLong;
7150      break;
7151    }
7152  }
7153
7154  QualType Type;
7155
7156  // Read the base type.
7157  switch (*Str++) {
7158  default: llvm_unreachable("Unknown builtin type letter!");
7159  case 'v':
7160    assert(HowLong == 0 && !Signed && !Unsigned &&
7161           "Bad modifiers used with 'v'!");
7162    Type = Context.VoidTy;
7163    break;
7164  case 'f':
7165    assert(HowLong == 0 && !Signed && !Unsigned &&
7166           "Bad modifiers used with 'f'!");
7167    Type = Context.FloatTy;
7168    break;
7169  case 'd':
7170    assert(HowLong < 2 && !Signed && !Unsigned &&
7171           "Bad modifiers used with 'd'!");
7172    if (HowLong)
7173      Type = Context.LongDoubleTy;
7174    else
7175      Type = Context.DoubleTy;
7176    break;
7177  case 's':
7178    assert(HowLong == 0 && "Bad modifiers used with 's'!");
7179    if (Unsigned)
7180      Type = Context.UnsignedShortTy;
7181    else
7182      Type = Context.ShortTy;
7183    break;
7184  case 'i':
7185    if (HowLong == 3)
7186      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
7187    else if (HowLong == 2)
7188      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
7189    else if (HowLong == 1)
7190      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
7191    else
7192      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
7193    break;
7194  case 'c':
7195    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
7196    if (Signed)
7197      Type = Context.SignedCharTy;
7198    else if (Unsigned)
7199      Type = Context.UnsignedCharTy;
7200    else
7201      Type = Context.CharTy;
7202    break;
7203  case 'b': // boolean
7204    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
7205    Type = Context.BoolTy;
7206    break;
7207  case 'z':  // size_t.
7208    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
7209    Type = Context.getSizeType();
7210    break;
7211  case 'F':
7212    Type = Context.getCFConstantStringType();
7213    break;
7214  case 'G':
7215    Type = Context.getObjCIdType();
7216    break;
7217  case 'H':
7218    Type = Context.getObjCSelType();
7219    break;
7220  case 'M':
7221    Type = Context.getObjCSuperType();
7222    break;
7223  case 'a':
7224    Type = Context.getBuiltinVaListType();
7225    assert(!Type.isNull() && "builtin va list type not initialized!");
7226    break;
7227  case 'A':
7228    // This is a "reference" to a va_list; however, what exactly
7229    // this means depends on how va_list is defined. There are two
7230    // different kinds of va_list: ones passed by value, and ones
7231    // passed by reference.  An example of a by-value va_list is
7232    // x86, where va_list is a char*. An example of by-ref va_list
7233    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
7234    // we want this argument to be a char*&; for x86-64, we want
7235    // it to be a __va_list_tag*.
7236    Type = Context.getBuiltinVaListType();
7237    assert(!Type.isNull() && "builtin va list type not initialized!");
7238    if (Type->isArrayType())
7239      Type = Context.getArrayDecayedType(Type);
7240    else
7241      Type = Context.getLValueReferenceType(Type);
7242    break;
7243  case 'V': {
7244    char *End;
7245    unsigned NumElements = strtoul(Str, &End, 10);
7246    assert(End != Str && "Missing vector size");
7247    Str = End;
7248
7249    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
7250                                             RequiresICE, false);
7251    assert(!RequiresICE && "Can't require vector ICE");
7252
7253    // TODO: No way to make AltiVec vectors in builtins yet.
7254    Type = Context.getVectorType(ElementType, NumElements,
7255                                 VectorType::GenericVector);
7256    break;
7257  }
7258  case 'E': {
7259    char *End;
7260
7261    unsigned NumElements = strtoul(Str, &End, 10);
7262    assert(End != Str && "Missing vector size");
7263
7264    Str = End;
7265
7266    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
7267                                             false);
7268    Type = Context.getExtVectorType(ElementType, NumElements);
7269    break;
7270  }
7271  case 'X': {
7272    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
7273                                             false);
7274    assert(!RequiresICE && "Can't require complex ICE");
7275    Type = Context.getComplexType(ElementType);
7276    break;
7277  }
7278  case 'Y' : {
7279    Type = Context.getPointerDiffType();
7280    break;
7281  }
7282  case 'P':
7283    Type = Context.getFILEType();
7284    if (Type.isNull()) {
7285      Error = ASTContext::GE_Missing_stdio;
7286      return QualType();
7287    }
7288    break;
7289  case 'J':
7290    if (Signed)
7291      Type = Context.getsigjmp_bufType();
7292    else
7293      Type = Context.getjmp_bufType();
7294
7295    if (Type.isNull()) {
7296      Error = ASTContext::GE_Missing_setjmp;
7297      return QualType();
7298    }
7299    break;
7300  case 'K':
7301    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'K'!");
7302    Type = Context.getucontext_tType();
7303
7304    if (Type.isNull()) {
7305      Error = ASTContext::GE_Missing_ucontext;
7306      return QualType();
7307    }
7308    break;
7309  case 'p':
7310    Type = Context.getProcessIDType();
7311    break;
7312  }
7313
7314  // If there are modifiers and if we're allowed to parse them, go for it.
7315  Done = !AllowTypeModifiers;
7316  while (!Done) {
7317    switch (char c = *Str++) {
7318    default: Done = true; --Str; break;
7319    case '*':
7320    case '&': {
7321      // Both pointers and references can have their pointee types
7322      // qualified with an address space.
7323      char *End;
7324      unsigned AddrSpace = strtoul(Str, &End, 10);
7325      if (End != Str && AddrSpace != 0) {
7326        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
7327        Str = End;
7328      }
7329      if (c == '*')
7330        Type = Context.getPointerType(Type);
7331      else
7332        Type = Context.getLValueReferenceType(Type);
7333      break;
7334    }
7335    // FIXME: There's no way to have a built-in with an rvalue ref arg.
7336    case 'C':
7337      Type = Type.withConst();
7338      break;
7339    case 'D':
7340      Type = Context.getVolatileType(Type);
7341      break;
7342    case 'R':
7343      Type = Type.withRestrict();
7344      break;
7345    }
7346  }
7347
7348  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
7349         "Integer constant 'I' type must be an integer");
7350
7351  return Type;
7352}
7353
7354/// GetBuiltinType - Return the type for the specified builtin.
7355QualType ASTContext::GetBuiltinType(unsigned Id,
7356                                    GetBuiltinTypeError &Error,
7357                                    unsigned *IntegerConstantArgs) const {
7358  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
7359
7360  SmallVector<QualType, 8> ArgTypes;
7361
7362  bool RequiresICE = false;
7363  Error = GE_None;
7364  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
7365                                       RequiresICE, true);
7366  if (Error != GE_None)
7367    return QualType();
7368
7369  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
7370
7371  while (TypeStr[0] && TypeStr[0] != '.') {
7372    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
7373    if (Error != GE_None)
7374      return QualType();
7375
7376    // If this argument is required to be an IntegerConstantExpression and the
7377    // caller cares, fill in the bitmask we return.
7378    if (RequiresICE && IntegerConstantArgs)
7379      *IntegerConstantArgs |= 1 << ArgTypes.size();
7380
7381    // Do array -> pointer decay.  The builtin should use the decayed type.
7382    if (Ty->isArrayType())
7383      Ty = getArrayDecayedType(Ty);
7384
7385    ArgTypes.push_back(Ty);
7386  }
7387
7388  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
7389         "'.' should only occur at end of builtin type list!");
7390
7391  FunctionType::ExtInfo EI;
7392  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
7393
7394  bool Variadic = (TypeStr[0] == '.');
7395
7396  // We really shouldn't be making a no-proto type here, especially in C++.
7397  if (ArgTypes.empty() && Variadic)
7398    return getFunctionNoProtoType(ResType, EI);
7399
7400  FunctionProtoType::ExtProtoInfo EPI;
7401  EPI.ExtInfo = EI;
7402  EPI.Variadic = Variadic;
7403
7404  return getFunctionType(ResType, ArgTypes.data(), ArgTypes.size(), EPI);
7405}
7406
7407GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
7408  GVALinkage External = GVA_StrongExternal;
7409
7410  Linkage L = FD->getLinkage();
7411  switch (L) {
7412  case NoLinkage:
7413  case InternalLinkage:
7414  case UniqueExternalLinkage:
7415    return GVA_Internal;
7416
7417  case ExternalLinkage:
7418    switch (FD->getTemplateSpecializationKind()) {
7419    case TSK_Undeclared:
7420    case TSK_ExplicitSpecialization:
7421      External = GVA_StrongExternal;
7422      break;
7423
7424    case TSK_ExplicitInstantiationDefinition:
7425      return GVA_ExplicitTemplateInstantiation;
7426
7427    case TSK_ExplicitInstantiationDeclaration:
7428    case TSK_ImplicitInstantiation:
7429      External = GVA_TemplateInstantiation;
7430      break;
7431    }
7432  }
7433
7434  if (!FD->isInlined())
7435    return External;
7436
7437  if (!getLangOpts().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
7438    // GNU or C99 inline semantics. Determine whether this symbol should be
7439    // externally visible.
7440    if (FD->isInlineDefinitionExternallyVisible())
7441      return External;
7442
7443    // C99 inline semantics, where the symbol is not externally visible.
7444    return GVA_C99Inline;
7445  }
7446
7447  // C++0x [temp.explicit]p9:
7448  //   [ Note: The intent is that an inline function that is the subject of
7449  //   an explicit instantiation declaration will still be implicitly
7450  //   instantiated when used so that the body can be considered for
7451  //   inlining, but that no out-of-line copy of the inline function would be
7452  //   generated in the translation unit. -- end note ]
7453  if (FD->getTemplateSpecializationKind()
7454                                       == TSK_ExplicitInstantiationDeclaration)
7455    return GVA_C99Inline;
7456
7457  return GVA_CXXInline;
7458}
7459
7460GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
7461  // If this is a static data member, compute the kind of template
7462  // specialization. Otherwise, this variable is not part of a
7463  // template.
7464  TemplateSpecializationKind TSK = TSK_Undeclared;
7465  if (VD->isStaticDataMember())
7466    TSK = VD->getTemplateSpecializationKind();
7467
7468  Linkage L = VD->getLinkage();
7469  assert (!(L == ExternalLinkage && getLangOpts().CPlusPlus &&
7470            VD->getType()->getLinkage() == UniqueExternalLinkage));
7471
7472  switch (L) {
7473  case NoLinkage:
7474  case InternalLinkage:
7475  case UniqueExternalLinkage:
7476    return GVA_Internal;
7477
7478  case ExternalLinkage:
7479    switch (TSK) {
7480    case TSK_Undeclared:
7481    case TSK_ExplicitSpecialization:
7482      return GVA_StrongExternal;
7483
7484    case TSK_ExplicitInstantiationDeclaration:
7485      llvm_unreachable("Variable should not be instantiated");
7486      // Fall through to treat this like any other instantiation.
7487
7488    case TSK_ExplicitInstantiationDefinition:
7489      return GVA_ExplicitTemplateInstantiation;
7490
7491    case TSK_ImplicitInstantiation:
7492      return GVA_TemplateInstantiation;
7493    }
7494  }
7495
7496  llvm_unreachable("Invalid Linkage!");
7497}
7498
7499bool ASTContext::DeclMustBeEmitted(const Decl *D) {
7500  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
7501    if (!VD->isFileVarDecl())
7502      return false;
7503  } else if (!isa<FunctionDecl>(D))
7504    return false;
7505
7506  // Weak references don't produce any output by themselves.
7507  if (D->hasAttr<WeakRefAttr>())
7508    return false;
7509
7510  // Aliases and used decls are required.
7511  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
7512    return true;
7513
7514  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
7515    // Forward declarations aren't required.
7516    if (!FD->doesThisDeclarationHaveABody())
7517      return FD->doesDeclarationForceExternallyVisibleDefinition();
7518
7519    // Constructors and destructors are required.
7520    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
7521      return true;
7522
7523    // The key function for a class is required.
7524    if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
7525      const CXXRecordDecl *RD = MD->getParent();
7526      if (MD->isOutOfLine() && RD->isDynamicClass()) {
7527        const CXXMethodDecl *KeyFunc = getKeyFunction(RD);
7528        if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
7529          return true;
7530      }
7531    }
7532
7533    GVALinkage Linkage = GetGVALinkageForFunction(FD);
7534
7535    // static, static inline, always_inline, and extern inline functions can
7536    // always be deferred.  Normal inline functions can be deferred in C99/C++.
7537    // Implicit template instantiations can also be deferred in C++.
7538    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
7539        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
7540      return false;
7541    return true;
7542  }
7543
7544  const VarDecl *VD = cast<VarDecl>(D);
7545  assert(VD->isFileVarDecl() && "Expected file scoped var");
7546
7547  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
7548    return false;
7549
7550  // Variables that can be needed in other TUs are required.
7551  GVALinkage L = GetGVALinkageForVariable(VD);
7552  if (L != GVA_Internal && L != GVA_TemplateInstantiation)
7553    return true;
7554
7555  // Variables that have destruction with side-effects are required.
7556  if (VD->getType().isDestructedType())
7557    return true;
7558
7559  // Variables that have initialization with side-effects are required.
7560  if (VD->getInit() && VD->getInit()->HasSideEffects(*this))
7561    return true;
7562
7563  return false;
7564}
7565
7566CallingConv ASTContext::getDefaultCXXMethodCallConv(bool isVariadic) {
7567  // Pass through to the C++ ABI object
7568  return ABI->getDefaultMethodCallConv(isVariadic);
7569}
7570
7571CallingConv ASTContext::getCanonicalCallConv(CallingConv CC) const {
7572  if (CC == CC_C && !LangOpts.MRTD && getTargetInfo().getCXXABI() != CXXABI_Microsoft)
7573    return CC_Default;
7574  return CC;
7575}
7576
7577bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
7578  // Pass through to the C++ ABI object
7579  return ABI->isNearlyEmpty(RD);
7580}
7581
7582MangleContext *ASTContext::createMangleContext() {
7583  switch (Target->getCXXABI()) {
7584  case CXXABI_ARM:
7585  case CXXABI_Itanium:
7586    return createItaniumMangleContext(*this, getDiagnostics());
7587  case CXXABI_Microsoft:
7588    return createMicrosoftMangleContext(*this, getDiagnostics());
7589  }
7590  llvm_unreachable("Unsupported ABI");
7591}
7592
7593CXXABI::~CXXABI() {}
7594
7595size_t ASTContext::getSideTableAllocatedMemory() const {
7596  return ASTRecordLayouts.getMemorySize()
7597    + llvm::capacity_in_bytes(ObjCLayouts)
7598    + llvm::capacity_in_bytes(KeyFunctions)
7599    + llvm::capacity_in_bytes(ObjCImpls)
7600    + llvm::capacity_in_bytes(BlockVarCopyInits)
7601    + llvm::capacity_in_bytes(DeclAttrs)
7602    + llvm::capacity_in_bytes(InstantiatedFromStaticDataMember)
7603    + llvm::capacity_in_bytes(InstantiatedFromUsingDecl)
7604    + llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl)
7605    + llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl)
7606    + llvm::capacity_in_bytes(OverriddenMethods)
7607    + llvm::capacity_in_bytes(Types)
7608    + llvm::capacity_in_bytes(VariableArrayTypes)
7609    + llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
7610}
7611
7612void ASTContext::addUnnamedTag(const TagDecl *Tag) {
7613  // FIXME: This mangling should be applied to function local classes too
7614  if (!Tag->getName().empty() || Tag->getTypedefNameForAnonDecl() ||
7615      !isa<CXXRecordDecl>(Tag->getParent()) || Tag->getLinkage() != ExternalLinkage)
7616    return;
7617
7618  std::pair<llvm::DenseMap<const DeclContext *, unsigned>::iterator, bool> P =
7619    UnnamedMangleContexts.insert(std::make_pair(Tag->getParent(), 0));
7620  UnnamedMangleNumbers.insert(std::make_pair(Tag, P.first->second++));
7621}
7622
7623int ASTContext::getUnnamedTagManglingNumber(const TagDecl *Tag) const {
7624  llvm::DenseMap<const TagDecl *, unsigned>::const_iterator I =
7625    UnnamedMangleNumbers.find(Tag);
7626  return I != UnnamedMangleNumbers.end() ? I->second : -1;
7627}
7628
7629unsigned ASTContext::getLambdaManglingNumber(CXXMethodDecl *CallOperator) {
7630  CXXRecordDecl *Lambda = CallOperator->getParent();
7631  return LambdaMangleContexts[Lambda->getDeclContext()]
7632           .getManglingNumber(CallOperator);
7633}
7634
7635
7636void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
7637  ParamIndices[D] = index;
7638}
7639
7640unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
7641  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
7642  assert(I != ParamIndices.end() &&
7643         "ParmIndices lacks entry set by ParmVarDecl");
7644  return I->second;
7645}
7646