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/DeclContextInternals.h"
23#include "clang/AST/DeclObjC.h"
24#include "clang/AST/DeclTemplate.h"
25#include "clang/AST/Expr.h"
26#include "clang/AST/ExprCXX.h"
27#include "clang/AST/ExternalASTSource.h"
28#include "clang/AST/Mangle.h"
29#include "clang/AST/MangleNumberingContext.h"
30#include "clang/AST/RecordLayout.h"
31#include "clang/AST/RecursiveASTVisitor.h"
32#include "clang/AST/TypeLoc.h"
33#include "clang/AST/VTableBuilder.h"
34#include "clang/Basic/Builtins.h"
35#include "clang/Basic/SourceManager.h"
36#include "clang/Basic/TargetInfo.h"
37#include "llvm/ADT/SmallString.h"
38#include "llvm/ADT/StringExtras.h"
39#include "llvm/ADT/Triple.h"
40#include "llvm/Support/Capacity.h"
41#include "llvm/Support/MathExtras.h"
42#include "llvm/Support/raw_ostream.h"
43#include <map>
44
45using namespace clang;
46
47unsigned ASTContext::NumImplicitDefaultConstructors;
48unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
49unsigned ASTContext::NumImplicitCopyConstructors;
50unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
51unsigned ASTContext::NumImplicitMoveConstructors;
52unsigned ASTContext::NumImplicitMoveConstructorsDeclared;
53unsigned ASTContext::NumImplicitCopyAssignmentOperators;
54unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
55unsigned ASTContext::NumImplicitMoveAssignmentOperators;
56unsigned ASTContext::NumImplicitMoveAssignmentOperatorsDeclared;
57unsigned ASTContext::NumImplicitDestructors;
58unsigned ASTContext::NumImplicitDestructorsDeclared;
59
60enum FloatingRank {
61  HalfRank, FloatRank, DoubleRank, LongDoubleRank
62};
63
64RawComment *ASTContext::getRawCommentForDeclNoCache(const Decl *D) const {
65  if (!CommentsLoaded && ExternalSource) {
66    ExternalSource->ReadComments();
67
68#ifndef NDEBUG
69    ArrayRef<RawComment *> RawComments = Comments.getComments();
70    assert(std::is_sorted(RawComments.begin(), RawComments.end(),
71                          BeforeThanCompare<RawComment>(SourceMgr)));
72#endif
73
74    CommentsLoaded = true;
75  }
76
77  assert(D);
78
79  // User can not attach documentation to implicit declarations.
80  if (D->isImplicit())
81    return nullptr;
82
83  // User can not attach documentation to implicit instantiations.
84  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
85    if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
86      return nullptr;
87  }
88
89  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
90    if (VD->isStaticDataMember() &&
91        VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
92      return nullptr;
93  }
94
95  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(D)) {
96    if (CRD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
97      return nullptr;
98  }
99
100  if (const ClassTemplateSpecializationDecl *CTSD =
101          dyn_cast<ClassTemplateSpecializationDecl>(D)) {
102    TemplateSpecializationKind TSK = CTSD->getSpecializationKind();
103    if (TSK == TSK_ImplicitInstantiation ||
104        TSK == TSK_Undeclared)
105      return nullptr;
106  }
107
108  if (const EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
109    if (ED->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
110      return nullptr;
111  }
112  if (const TagDecl *TD = dyn_cast<TagDecl>(D)) {
113    // When tag declaration (but not definition!) is part of the
114    // decl-specifier-seq of some other declaration, it doesn't get comment
115    if (TD->isEmbeddedInDeclarator() && !TD->isCompleteDefinition())
116      return nullptr;
117  }
118  // TODO: handle comments for function parameters properly.
119  if (isa<ParmVarDecl>(D))
120    return nullptr;
121
122  // TODO: we could look up template parameter documentation in the template
123  // documentation.
124  if (isa<TemplateTypeParmDecl>(D) ||
125      isa<NonTypeTemplateParmDecl>(D) ||
126      isa<TemplateTemplateParmDecl>(D))
127    return nullptr;
128
129  ArrayRef<RawComment *> RawComments = Comments.getComments();
130
131  // If there are no comments anywhere, we won't find anything.
132  if (RawComments.empty())
133    return nullptr;
134
135  // Find declaration location.
136  // For Objective-C declarations we generally don't expect to have multiple
137  // declarators, thus use declaration starting location as the "declaration
138  // location".
139  // For all other declarations multiple declarators are used quite frequently,
140  // so we use the location of the identifier as the "declaration location".
141  SourceLocation DeclLoc;
142  if (isa<ObjCMethodDecl>(D) || isa<ObjCContainerDecl>(D) ||
143      isa<ObjCPropertyDecl>(D) ||
144      isa<RedeclarableTemplateDecl>(D) ||
145      isa<ClassTemplateSpecializationDecl>(D))
146    DeclLoc = D->getLocStart();
147  else {
148    DeclLoc = D->getLocation();
149    if (DeclLoc.isMacroID()) {
150      if (isa<TypedefDecl>(D)) {
151        // If location of the typedef name is in a macro, it is because being
152        // declared via a macro. Try using declaration's starting location as
153        // the "declaration location".
154        DeclLoc = D->getLocStart();
155      } else if (const TagDecl *TD = dyn_cast<TagDecl>(D)) {
156        // If location of the tag decl is inside a macro, but the spelling of
157        // the tag name comes from a macro argument, it looks like a special
158        // macro like NS_ENUM is being used to define the tag decl.  In that
159        // case, adjust the source location to the expansion loc so that we can
160        // attach the comment to the tag decl.
161        if (SourceMgr.isMacroArgExpansion(DeclLoc) &&
162            TD->isCompleteDefinition())
163          DeclLoc = SourceMgr.getExpansionLoc(DeclLoc);
164      }
165    }
166  }
167
168  // If the declaration doesn't map directly to a location in a file, we
169  // can't find the comment.
170  if (DeclLoc.isInvalid() || !DeclLoc.isFileID())
171    return nullptr;
172
173  // Find the comment that occurs just after this declaration.
174  ArrayRef<RawComment *>::iterator Comment;
175  {
176    // When searching for comments during parsing, the comment we are looking
177    // for is usually among the last two comments we parsed -- check them
178    // first.
179    RawComment CommentAtDeclLoc(
180        SourceMgr, SourceRange(DeclLoc), false,
181        LangOpts.CommentOpts.ParseAllComments);
182    BeforeThanCompare<RawComment> Compare(SourceMgr);
183    ArrayRef<RawComment *>::iterator MaybeBeforeDecl = RawComments.end() - 1;
184    bool Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
185    if (!Found && RawComments.size() >= 2) {
186      MaybeBeforeDecl--;
187      Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
188    }
189
190    if (Found) {
191      Comment = MaybeBeforeDecl + 1;
192      assert(Comment == std::lower_bound(RawComments.begin(), RawComments.end(),
193                                         &CommentAtDeclLoc, Compare));
194    } else {
195      // Slow path.
196      Comment = std::lower_bound(RawComments.begin(), RawComments.end(),
197                                 &CommentAtDeclLoc, Compare);
198    }
199  }
200
201  // Decompose the location for the declaration and find the beginning of the
202  // file buffer.
203  std::pair<FileID, unsigned> DeclLocDecomp = SourceMgr.getDecomposedLoc(DeclLoc);
204
205  // First check whether we have a trailing comment.
206  if (Comment != RawComments.end() &&
207      (*Comment)->isDocumentation() && (*Comment)->isTrailingComment() &&
208      (isa<FieldDecl>(D) || isa<EnumConstantDecl>(D) || isa<VarDecl>(D) ||
209       isa<ObjCMethodDecl>(D) || isa<ObjCPropertyDecl>(D))) {
210    std::pair<FileID, unsigned> CommentBeginDecomp
211      = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getBegin());
212    // Check that Doxygen trailing comment comes after the declaration, starts
213    // on the same line and in the same file as the declaration.
214    if (DeclLocDecomp.first == CommentBeginDecomp.first &&
215        SourceMgr.getLineNumber(DeclLocDecomp.first, DeclLocDecomp.second)
216          == SourceMgr.getLineNumber(CommentBeginDecomp.first,
217                                     CommentBeginDecomp.second)) {
218      return *Comment;
219    }
220  }
221
222  // The comment just after the declaration was not a trailing comment.
223  // Let's look at the previous comment.
224  if (Comment == RawComments.begin())
225    return nullptr;
226  --Comment;
227
228  // Check that we actually have a non-member Doxygen comment.
229  if (!(*Comment)->isDocumentation() || (*Comment)->isTrailingComment())
230    return nullptr;
231
232  // Decompose the end of the comment.
233  std::pair<FileID, unsigned> CommentEndDecomp
234    = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getEnd());
235
236  // If the comment and the declaration aren't in the same file, then they
237  // aren't related.
238  if (DeclLocDecomp.first != CommentEndDecomp.first)
239    return nullptr;
240
241  // Get the corresponding buffer.
242  bool Invalid = false;
243  const char *Buffer = SourceMgr.getBufferData(DeclLocDecomp.first,
244                                               &Invalid).data();
245  if (Invalid)
246    return nullptr;
247
248  // Extract text between the comment and declaration.
249  StringRef Text(Buffer + CommentEndDecomp.second,
250                 DeclLocDecomp.second - CommentEndDecomp.second);
251
252  // There should be no other declarations or preprocessor directives between
253  // comment and declaration.
254  if (Text.find_first_of(";{}#@") != StringRef::npos)
255    return nullptr;
256
257  return *Comment;
258}
259
260namespace {
261/// If we have a 'templated' declaration for a template, adjust 'D' to
262/// refer to the actual template.
263/// If we have an implicit instantiation, adjust 'D' to refer to template.
264const Decl *adjustDeclToTemplate(const Decl *D) {
265  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
266    // Is this function declaration part of a function template?
267    if (const FunctionTemplateDecl *FTD = FD->getDescribedFunctionTemplate())
268      return FTD;
269
270    // Nothing to do if function is not an implicit instantiation.
271    if (FD->getTemplateSpecializationKind() != TSK_ImplicitInstantiation)
272      return D;
273
274    // Function is an implicit instantiation of a function template?
275    if (const FunctionTemplateDecl *FTD = FD->getPrimaryTemplate())
276      return FTD;
277
278    // Function is instantiated from a member definition of a class template?
279    if (const FunctionDecl *MemberDecl =
280            FD->getInstantiatedFromMemberFunction())
281      return MemberDecl;
282
283    return D;
284  }
285  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
286    // Static data member is instantiated from a member definition of a class
287    // template?
288    if (VD->isStaticDataMember())
289      if (const VarDecl *MemberDecl = VD->getInstantiatedFromStaticDataMember())
290        return MemberDecl;
291
292    return D;
293  }
294  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(D)) {
295    // Is this class declaration part of a class template?
296    if (const ClassTemplateDecl *CTD = CRD->getDescribedClassTemplate())
297      return CTD;
298
299    // Class is an implicit instantiation of a class template or partial
300    // specialization?
301    if (const ClassTemplateSpecializationDecl *CTSD =
302            dyn_cast<ClassTemplateSpecializationDecl>(CRD)) {
303      if (CTSD->getSpecializationKind() != TSK_ImplicitInstantiation)
304        return D;
305      llvm::PointerUnion<ClassTemplateDecl *,
306                         ClassTemplatePartialSpecializationDecl *>
307          PU = CTSD->getSpecializedTemplateOrPartial();
308      return PU.is<ClassTemplateDecl*>() ?
309          static_cast<const Decl*>(PU.get<ClassTemplateDecl *>()) :
310          static_cast<const Decl*>(
311              PU.get<ClassTemplatePartialSpecializationDecl *>());
312    }
313
314    // Class is instantiated from a member definition of a class template?
315    if (const MemberSpecializationInfo *Info =
316                   CRD->getMemberSpecializationInfo())
317      return Info->getInstantiatedFrom();
318
319    return D;
320  }
321  if (const EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
322    // Enum is instantiated from a member definition of a class template?
323    if (const EnumDecl *MemberDecl = ED->getInstantiatedFromMemberEnum())
324      return MemberDecl;
325
326    return D;
327  }
328  // FIXME: Adjust alias templates?
329  return D;
330}
331} // anonymous namespace
332
333const RawComment *ASTContext::getRawCommentForAnyRedecl(
334                                                const Decl *D,
335                                                const Decl **OriginalDecl) const {
336  D = adjustDeclToTemplate(D);
337
338  // Check whether we have cached a comment for this declaration already.
339  {
340    llvm::DenseMap<const Decl *, RawCommentAndCacheFlags>::iterator Pos =
341        RedeclComments.find(D);
342    if (Pos != RedeclComments.end()) {
343      const RawCommentAndCacheFlags &Raw = Pos->second;
344      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
345        if (OriginalDecl)
346          *OriginalDecl = Raw.getOriginalDecl();
347        return Raw.getRaw();
348      }
349    }
350  }
351
352  // Search for comments attached to declarations in the redeclaration chain.
353  const RawComment *RC = nullptr;
354  const Decl *OriginalDeclForRC = nullptr;
355  for (auto I : D->redecls()) {
356    llvm::DenseMap<const Decl *, RawCommentAndCacheFlags>::iterator Pos =
357        RedeclComments.find(I);
358    if (Pos != RedeclComments.end()) {
359      const RawCommentAndCacheFlags &Raw = Pos->second;
360      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
361        RC = Raw.getRaw();
362        OriginalDeclForRC = Raw.getOriginalDecl();
363        break;
364      }
365    } else {
366      RC = getRawCommentForDeclNoCache(I);
367      OriginalDeclForRC = I;
368      RawCommentAndCacheFlags Raw;
369      if (RC) {
370        // Call order swapped to work around ICE in VS2015 RTM (Release Win32)
371        // https://connect.microsoft.com/VisualStudio/feedback/details/1741530
372        Raw.setKind(RawCommentAndCacheFlags::FromDecl);
373        Raw.setRaw(RC);
374      } else
375        Raw.setKind(RawCommentAndCacheFlags::NoCommentInDecl);
376      Raw.setOriginalDecl(I);
377      RedeclComments[I] = Raw;
378      if (RC)
379        break;
380    }
381  }
382
383  // If we found a comment, it should be a documentation comment.
384  assert(!RC || RC->isDocumentation());
385
386  if (OriginalDecl)
387    *OriginalDecl = OriginalDeclForRC;
388
389  // Update cache for every declaration in the redeclaration chain.
390  RawCommentAndCacheFlags Raw;
391  Raw.setRaw(RC);
392  Raw.setKind(RawCommentAndCacheFlags::FromRedecl);
393  Raw.setOriginalDecl(OriginalDeclForRC);
394
395  for (auto I : D->redecls()) {
396    RawCommentAndCacheFlags &R = RedeclComments[I];
397    if (R.getKind() == RawCommentAndCacheFlags::NoCommentInDecl)
398      R = Raw;
399  }
400
401  return RC;
402}
403
404static void addRedeclaredMethods(const ObjCMethodDecl *ObjCMethod,
405                   SmallVectorImpl<const NamedDecl *> &Redeclared) {
406  const DeclContext *DC = ObjCMethod->getDeclContext();
407  if (const ObjCImplDecl *IMD = dyn_cast<ObjCImplDecl>(DC)) {
408    const ObjCInterfaceDecl *ID = IMD->getClassInterface();
409    if (!ID)
410      return;
411    // Add redeclared method here.
412    for (const auto *Ext : ID->known_extensions()) {
413      if (ObjCMethodDecl *RedeclaredMethod =
414            Ext->getMethod(ObjCMethod->getSelector(),
415                                  ObjCMethod->isInstanceMethod()))
416        Redeclared.push_back(RedeclaredMethod);
417    }
418  }
419}
420
421comments::FullComment *ASTContext::cloneFullComment(comments::FullComment *FC,
422                                                    const Decl *D) const {
423  comments::DeclInfo *ThisDeclInfo = new (*this) comments::DeclInfo;
424  ThisDeclInfo->CommentDecl = D;
425  ThisDeclInfo->IsFilled = false;
426  ThisDeclInfo->fill();
427  ThisDeclInfo->CommentDecl = FC->getDecl();
428  if (!ThisDeclInfo->TemplateParameters)
429    ThisDeclInfo->TemplateParameters = FC->getDeclInfo()->TemplateParameters;
430  comments::FullComment *CFC =
431    new (*this) comments::FullComment(FC->getBlocks(),
432                                      ThisDeclInfo);
433  return CFC;
434}
435
436comments::FullComment *ASTContext::getLocalCommentForDeclUncached(const Decl *D) const {
437  const RawComment *RC = getRawCommentForDeclNoCache(D);
438  return RC ? RC->parse(*this, nullptr, D) : nullptr;
439}
440
441comments::FullComment *ASTContext::getCommentForDecl(
442                                              const Decl *D,
443                                              const Preprocessor *PP) const {
444  if (D->isInvalidDecl())
445    return nullptr;
446  D = adjustDeclToTemplate(D);
447
448  const Decl *Canonical = D->getCanonicalDecl();
449  llvm::DenseMap<const Decl *, comments::FullComment *>::iterator Pos =
450      ParsedComments.find(Canonical);
451
452  if (Pos != ParsedComments.end()) {
453    if (Canonical != D) {
454      comments::FullComment *FC = Pos->second;
455      comments::FullComment *CFC = cloneFullComment(FC, D);
456      return CFC;
457    }
458    return Pos->second;
459  }
460
461  const Decl *OriginalDecl;
462
463  const RawComment *RC = getRawCommentForAnyRedecl(D, &OriginalDecl);
464  if (!RC) {
465    if (isa<ObjCMethodDecl>(D) || isa<FunctionDecl>(D)) {
466      SmallVector<const NamedDecl*, 8> Overridden;
467      const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D);
468      if (OMD && OMD->isPropertyAccessor())
469        if (const ObjCPropertyDecl *PDecl = OMD->findPropertyDecl())
470          if (comments::FullComment *FC = getCommentForDecl(PDecl, PP))
471            return cloneFullComment(FC, D);
472      if (OMD)
473        addRedeclaredMethods(OMD, Overridden);
474      getOverriddenMethods(dyn_cast<NamedDecl>(D), Overridden);
475      for (unsigned i = 0, e = Overridden.size(); i < e; i++)
476        if (comments::FullComment *FC = getCommentForDecl(Overridden[i], PP))
477          return cloneFullComment(FC, D);
478    }
479    else if (const TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(D)) {
480      // Attach any tag type's documentation to its typedef if latter
481      // does not have one of its own.
482      QualType QT = TD->getUnderlyingType();
483      if (const TagType *TT = QT->getAs<TagType>())
484        if (const Decl *TD = TT->getDecl())
485          if (comments::FullComment *FC = getCommentForDecl(TD, PP))
486            return cloneFullComment(FC, D);
487    }
488    else if (const ObjCInterfaceDecl *IC = dyn_cast<ObjCInterfaceDecl>(D)) {
489      while (IC->getSuperClass()) {
490        IC = IC->getSuperClass();
491        if (comments::FullComment *FC = getCommentForDecl(IC, PP))
492          return cloneFullComment(FC, D);
493      }
494    }
495    else if (const ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(D)) {
496      if (const ObjCInterfaceDecl *IC = CD->getClassInterface())
497        if (comments::FullComment *FC = getCommentForDecl(IC, PP))
498          return cloneFullComment(FC, D);
499    }
500    else if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D)) {
501      if (!(RD = RD->getDefinition()))
502        return nullptr;
503      // Check non-virtual bases.
504      for (const auto &I : RD->bases()) {
505        if (I.isVirtual() || (I.getAccessSpecifier() != AS_public))
506          continue;
507        QualType Ty = I.getType();
508        if (Ty.isNull())
509          continue;
510        if (const CXXRecordDecl *NonVirtualBase = Ty->getAsCXXRecordDecl()) {
511          if (!(NonVirtualBase= NonVirtualBase->getDefinition()))
512            continue;
513
514          if (comments::FullComment *FC = getCommentForDecl((NonVirtualBase), PP))
515            return cloneFullComment(FC, D);
516        }
517      }
518      // Check virtual bases.
519      for (const auto &I : RD->vbases()) {
520        if (I.getAccessSpecifier() != AS_public)
521          continue;
522        QualType Ty = I.getType();
523        if (Ty.isNull())
524          continue;
525        if (const CXXRecordDecl *VirtualBase = Ty->getAsCXXRecordDecl()) {
526          if (!(VirtualBase= VirtualBase->getDefinition()))
527            continue;
528          if (comments::FullComment *FC = getCommentForDecl((VirtualBase), PP))
529            return cloneFullComment(FC, D);
530        }
531      }
532    }
533    return nullptr;
534  }
535
536  // If the RawComment was attached to other redeclaration of this Decl, we
537  // should parse the comment in context of that other Decl.  This is important
538  // because comments can contain references to parameter names which can be
539  // different across redeclarations.
540  if (D != OriginalDecl)
541    return getCommentForDecl(OriginalDecl, PP);
542
543  comments::FullComment *FC = RC->parse(*this, PP, D);
544  ParsedComments[Canonical] = FC;
545  return FC;
546}
547
548void
549ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
550                                               TemplateTemplateParmDecl *Parm) {
551  ID.AddInteger(Parm->getDepth());
552  ID.AddInteger(Parm->getPosition());
553  ID.AddBoolean(Parm->isParameterPack());
554
555  TemplateParameterList *Params = Parm->getTemplateParameters();
556  ID.AddInteger(Params->size());
557  for (TemplateParameterList::const_iterator P = Params->begin(),
558                                          PEnd = Params->end();
559       P != PEnd; ++P) {
560    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
561      ID.AddInteger(0);
562      ID.AddBoolean(TTP->isParameterPack());
563      continue;
564    }
565
566    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
567      ID.AddInteger(1);
568      ID.AddBoolean(NTTP->isParameterPack());
569      ID.AddPointer(NTTP->getType().getCanonicalType().getAsOpaquePtr());
570      if (NTTP->isExpandedParameterPack()) {
571        ID.AddBoolean(true);
572        ID.AddInteger(NTTP->getNumExpansionTypes());
573        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
574          QualType T = NTTP->getExpansionType(I);
575          ID.AddPointer(T.getCanonicalType().getAsOpaquePtr());
576        }
577      } else
578        ID.AddBoolean(false);
579      continue;
580    }
581
582    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
583    ID.AddInteger(2);
584    Profile(ID, TTP);
585  }
586}
587
588TemplateTemplateParmDecl *
589ASTContext::getCanonicalTemplateTemplateParmDecl(
590                                          TemplateTemplateParmDecl *TTP) const {
591  // Check if we already have a canonical template template parameter.
592  llvm::FoldingSetNodeID ID;
593  CanonicalTemplateTemplateParm::Profile(ID, TTP);
594  void *InsertPos = nullptr;
595  CanonicalTemplateTemplateParm *Canonical
596    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
597  if (Canonical)
598    return Canonical->getParam();
599
600  // Build a canonical template parameter list.
601  TemplateParameterList *Params = TTP->getTemplateParameters();
602  SmallVector<NamedDecl *, 4> CanonParams;
603  CanonParams.reserve(Params->size());
604  for (TemplateParameterList::const_iterator P = Params->begin(),
605                                          PEnd = Params->end();
606       P != PEnd; ++P) {
607    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
608      CanonParams.push_back(
609                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
610                                               SourceLocation(),
611                                               SourceLocation(),
612                                               TTP->getDepth(),
613                                               TTP->getIndex(), nullptr, false,
614                                               TTP->isParameterPack()));
615    else if (NonTypeTemplateParmDecl *NTTP
616             = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
617      QualType T = getCanonicalType(NTTP->getType());
618      TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
619      NonTypeTemplateParmDecl *Param;
620      if (NTTP->isExpandedParameterPack()) {
621        SmallVector<QualType, 2> ExpandedTypes;
622        SmallVector<TypeSourceInfo *, 2> ExpandedTInfos;
623        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
624          ExpandedTypes.push_back(getCanonicalType(NTTP->getExpansionType(I)));
625          ExpandedTInfos.push_back(
626                                getTrivialTypeSourceInfo(ExpandedTypes.back()));
627        }
628
629        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
630                                                SourceLocation(),
631                                                SourceLocation(),
632                                                NTTP->getDepth(),
633                                                NTTP->getPosition(), nullptr,
634                                                T,
635                                                TInfo,
636                                                ExpandedTypes.data(),
637                                                ExpandedTypes.size(),
638                                                ExpandedTInfos.data());
639      } else {
640        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
641                                                SourceLocation(),
642                                                SourceLocation(),
643                                                NTTP->getDepth(),
644                                                NTTP->getPosition(), nullptr,
645                                                T,
646                                                NTTP->isParameterPack(),
647                                                TInfo);
648      }
649      CanonParams.push_back(Param);
650
651    } else
652      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
653                                           cast<TemplateTemplateParmDecl>(*P)));
654  }
655
656  TemplateTemplateParmDecl *CanonTTP
657    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
658                                       SourceLocation(), TTP->getDepth(),
659                                       TTP->getPosition(),
660                                       TTP->isParameterPack(),
661                                       nullptr,
662                         TemplateParameterList::Create(*this, SourceLocation(),
663                                                       SourceLocation(),
664                                                       CanonParams,
665                                                       SourceLocation()));
666
667  // Get the new insert position for the node we care about.
668  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
669  assert(!Canonical && "Shouldn't be in the map!");
670  (void)Canonical;
671
672  // Create the canonical template template parameter entry.
673  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
674  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
675  return CanonTTP;
676}
677
678CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
679  if (!LangOpts.CPlusPlus) return nullptr;
680
681  switch (T.getCXXABI().getKind()) {
682  case TargetCXXABI::GenericARM: // Same as Itanium at this level
683  case TargetCXXABI::iOS:
684  case TargetCXXABI::iOS64:
685  case TargetCXXABI::WatchOS:
686  case TargetCXXABI::GenericAArch64:
687  case TargetCXXABI::GenericMIPS:
688  case TargetCXXABI::GenericItanium:
689  case TargetCXXABI::WebAssembly:
690    return CreateItaniumCXXABI(*this);
691  case TargetCXXABI::Microsoft:
692    return CreateMicrosoftCXXABI(*this);
693  }
694  llvm_unreachable("Invalid CXXABI type!");
695}
696
697static const LangAS::Map *getAddressSpaceMap(const TargetInfo &T,
698                                             const LangOptions &LOpts) {
699  if (LOpts.FakeAddressSpaceMap) {
700    // The fake address space map must have a distinct entry for each
701    // language-specific address space.
702    static const unsigned FakeAddrSpaceMap[] = {
703      1, // opencl_global
704      2, // opencl_local
705      3, // opencl_constant
706      4, // opencl_generic
707      5, // cuda_device
708      6, // cuda_constant
709      7  // cuda_shared
710    };
711    return &FakeAddrSpaceMap;
712  } else {
713    return &T.getAddressSpaceMap();
714  }
715}
716
717static bool isAddrSpaceMapManglingEnabled(const TargetInfo &TI,
718                                          const LangOptions &LangOpts) {
719  switch (LangOpts.getAddressSpaceMapMangling()) {
720  case LangOptions::ASMM_Target:
721    return TI.useAddressSpaceMapMangling();
722  case LangOptions::ASMM_On:
723    return true;
724  case LangOptions::ASMM_Off:
725    return false;
726  }
727  llvm_unreachable("getAddressSpaceMapMangling() doesn't cover anything.");
728}
729
730ASTContext::ASTContext(LangOptions &LOpts, SourceManager &SM,
731                       IdentifierTable &idents, SelectorTable &sels,
732                       Builtin::Context &builtins)
733    : FunctionProtoTypes(this_()), TemplateSpecializationTypes(this_()),
734      DependentTemplateSpecializationTypes(this_()),
735      SubstTemplateTemplateParmPacks(this_()),
736      GlobalNestedNameSpecifier(nullptr), Int128Decl(nullptr),
737      UInt128Decl(nullptr), Float128StubDecl(nullptr),
738      BuiltinVaListDecl(nullptr), BuiltinMSVaListDecl(nullptr),
739      ObjCIdDecl(nullptr), ObjCSelDecl(nullptr), ObjCClassDecl(nullptr),
740      ObjCProtocolClassDecl(nullptr), BOOLDecl(nullptr),
741      CFConstantStringTypeDecl(nullptr), ObjCInstanceTypeDecl(nullptr),
742      FILEDecl(nullptr), jmp_bufDecl(nullptr), sigjmp_bufDecl(nullptr),
743      ucontext_tDecl(nullptr), BlockDescriptorType(nullptr),
744      BlockDescriptorExtendedType(nullptr), cudaConfigureCallDecl(nullptr),
745      FirstLocalImport(), LastLocalImport(), ExternCContext(nullptr),
746      MakeIntegerSeqDecl(nullptr), SourceMgr(SM), LangOpts(LOpts),
747      SanitizerBL(new SanitizerBlacklist(LangOpts.SanitizerBlacklistFiles, SM)),
748      AddrSpaceMap(nullptr), Target(nullptr), AuxTarget(nullptr),
749      PrintingPolicy(LOpts), Idents(idents), Selectors(sels),
750      BuiltinInfo(builtins), DeclarationNames(*this), ExternalSource(nullptr),
751      Listener(nullptr), Comments(SM), CommentsLoaded(false),
752      CommentCommandTraits(BumpAlloc, LOpts.CommentOpts), LastSDM(nullptr, 0) {
753  TUDecl = TranslationUnitDecl::Create(*this);
754}
755
756ASTContext::~ASTContext() {
757  ReleaseParentMapEntries();
758
759  // Release the DenseMaps associated with DeclContext objects.
760  // FIXME: Is this the ideal solution?
761  ReleaseDeclContextMaps();
762
763  // Call all of the deallocation functions on all of their targets.
764  for (auto &Pair : Deallocations)
765    (Pair.first)(Pair.second);
766
767  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
768  // because they can contain DenseMaps.
769  for (llvm::DenseMap<const ObjCContainerDecl*,
770       const ASTRecordLayout*>::iterator
771       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
772    // Increment in loop to prevent using deallocated memory.
773    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
774      R->Destroy(*this);
775
776  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
777       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
778    // Increment in loop to prevent using deallocated memory.
779    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
780      R->Destroy(*this);
781  }
782
783  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
784                                                    AEnd = DeclAttrs.end();
785       A != AEnd; ++A)
786    A->second->~AttrVec();
787
788  for (std::pair<const MaterializeTemporaryExpr *, APValue *> &MTVPair :
789       MaterializedTemporaryValues)
790    MTVPair.second->~APValue();
791
792  llvm::DeleteContainerSeconds(MangleNumberingContexts);
793}
794
795void ASTContext::ReleaseParentMapEntries() {
796  if (!PointerParents) return;
797  for (const auto &Entry : *PointerParents) {
798    if (Entry.second.is<ast_type_traits::DynTypedNode *>()) {
799      delete Entry.second.get<ast_type_traits::DynTypedNode *>();
800    } else if (Entry.second.is<ParentVector *>()) {
801      delete Entry.second.get<ParentVector *>();
802    }
803  }
804  for (const auto &Entry : *OtherParents) {
805    if (Entry.second.is<ast_type_traits::DynTypedNode *>()) {
806      delete Entry.second.get<ast_type_traits::DynTypedNode *>();
807    } else if (Entry.second.is<ParentVector *>()) {
808      delete Entry.second.get<ParentVector *>();
809    }
810  }
811}
812
813void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
814  Deallocations.push_back({Callback, Data});
815}
816
817void
818ASTContext::setExternalSource(IntrusiveRefCntPtr<ExternalASTSource> Source) {
819  ExternalSource = Source;
820}
821
822void ASTContext::PrintStats() const {
823  llvm::errs() << "\n*** AST Context Stats:\n";
824  llvm::errs() << "  " << Types.size() << " types total.\n";
825
826  unsigned counts[] = {
827#define TYPE(Name, Parent) 0,
828#define ABSTRACT_TYPE(Name, Parent)
829#include "clang/AST/TypeNodes.def"
830    0 // Extra
831  };
832
833  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
834    Type *T = Types[i];
835    counts[(unsigned)T->getTypeClass()]++;
836  }
837
838  unsigned Idx = 0;
839  unsigned TotalBytes = 0;
840#define TYPE(Name, Parent)                                              \
841  if (counts[Idx])                                                      \
842    llvm::errs() << "    " << counts[Idx] << " " << #Name               \
843                 << " types\n";                                         \
844  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
845  ++Idx;
846#define ABSTRACT_TYPE(Name, Parent)
847#include "clang/AST/TypeNodes.def"
848
849  llvm::errs() << "Total bytes = " << TotalBytes << "\n";
850
851  // Implicit special member functions.
852  llvm::errs() << NumImplicitDefaultConstructorsDeclared << "/"
853               << NumImplicitDefaultConstructors
854               << " implicit default constructors created\n";
855  llvm::errs() << NumImplicitCopyConstructorsDeclared << "/"
856               << NumImplicitCopyConstructors
857               << " implicit copy constructors created\n";
858  if (getLangOpts().CPlusPlus)
859    llvm::errs() << NumImplicitMoveConstructorsDeclared << "/"
860                 << NumImplicitMoveConstructors
861                 << " implicit move constructors created\n";
862  llvm::errs() << NumImplicitCopyAssignmentOperatorsDeclared << "/"
863               << NumImplicitCopyAssignmentOperators
864               << " implicit copy assignment operators created\n";
865  if (getLangOpts().CPlusPlus)
866    llvm::errs() << NumImplicitMoveAssignmentOperatorsDeclared << "/"
867                 << NumImplicitMoveAssignmentOperators
868                 << " implicit move assignment operators created\n";
869  llvm::errs() << NumImplicitDestructorsDeclared << "/"
870               << NumImplicitDestructors
871               << " implicit destructors created\n";
872
873  if (ExternalSource) {
874    llvm::errs() << "\n";
875    ExternalSource->PrintStats();
876  }
877
878  BumpAlloc.PrintStats();
879}
880
881void ASTContext::mergeDefinitionIntoModule(NamedDecl *ND, Module *M,
882                                           bool NotifyListeners) {
883  if (NotifyListeners)
884    if (auto *Listener = getASTMutationListener())
885      Listener->RedefinedHiddenDefinition(ND, M);
886
887  if (getLangOpts().ModulesLocalVisibility)
888    MergedDefModules[ND].push_back(M);
889  else
890    ND->setHidden(false);
891}
892
893void ASTContext::deduplicateMergedDefinitonsFor(NamedDecl *ND) {
894  auto It = MergedDefModules.find(ND);
895  if (It == MergedDefModules.end())
896    return;
897
898  auto &Merged = It->second;
899  llvm::DenseSet<Module*> Found;
900  for (Module *&M : Merged)
901    if (!Found.insert(M).second)
902      M = nullptr;
903  Merged.erase(std::remove(Merged.begin(), Merged.end(), nullptr), Merged.end());
904}
905
906ExternCContextDecl *ASTContext::getExternCContextDecl() const {
907  if (!ExternCContext)
908    ExternCContext = ExternCContextDecl::Create(*this, getTranslationUnitDecl());
909
910  return ExternCContext;
911}
912
913BuiltinTemplateDecl *
914ASTContext::buildBuiltinTemplateDecl(BuiltinTemplateKind BTK,
915                                     const IdentifierInfo *II) const {
916  auto *BuiltinTemplate = BuiltinTemplateDecl::Create(*this, TUDecl, II, BTK);
917  BuiltinTemplate->setImplicit();
918  TUDecl->addDecl(BuiltinTemplate);
919
920  return BuiltinTemplate;
921}
922
923BuiltinTemplateDecl *
924ASTContext::getMakeIntegerSeqDecl() const {
925  if (!MakeIntegerSeqDecl)
926    MakeIntegerSeqDecl = buildBuiltinTemplateDecl(BTK__make_integer_seq,
927                                                  getMakeIntegerSeqName());
928  return MakeIntegerSeqDecl;
929}
930
931RecordDecl *ASTContext::buildImplicitRecord(StringRef Name,
932                                            RecordDecl::TagKind TK) const {
933  SourceLocation Loc;
934  RecordDecl *NewDecl;
935  if (getLangOpts().CPlusPlus)
936    NewDecl = CXXRecordDecl::Create(*this, TK, getTranslationUnitDecl(), Loc,
937                                    Loc, &Idents.get(Name));
938  else
939    NewDecl = RecordDecl::Create(*this, TK, getTranslationUnitDecl(), Loc, Loc,
940                                 &Idents.get(Name));
941  NewDecl->setImplicit();
942  NewDecl->addAttr(TypeVisibilityAttr::CreateImplicit(
943      const_cast<ASTContext &>(*this), TypeVisibilityAttr::Default));
944  return NewDecl;
945}
946
947TypedefDecl *ASTContext::buildImplicitTypedef(QualType T,
948                                              StringRef Name) const {
949  TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
950  TypedefDecl *NewDecl = TypedefDecl::Create(
951      const_cast<ASTContext &>(*this), getTranslationUnitDecl(),
952      SourceLocation(), SourceLocation(), &Idents.get(Name), TInfo);
953  NewDecl->setImplicit();
954  return NewDecl;
955}
956
957TypedefDecl *ASTContext::getInt128Decl() const {
958  if (!Int128Decl)
959    Int128Decl = buildImplicitTypedef(Int128Ty, "__int128_t");
960  return Int128Decl;
961}
962
963TypedefDecl *ASTContext::getUInt128Decl() const {
964  if (!UInt128Decl)
965    UInt128Decl = buildImplicitTypedef(UnsignedInt128Ty, "__uint128_t");
966  return UInt128Decl;
967}
968
969TypeDecl *ASTContext::getFloat128StubType() const {
970  assert(LangOpts.CPlusPlus && "should only be called for c++");
971  if (!Float128StubDecl)
972    Float128StubDecl = buildImplicitRecord("__float128");
973
974  return Float128StubDecl;
975}
976
977void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
978  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
979  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
980  Types.push_back(Ty);
981}
982
983void ASTContext::InitBuiltinTypes(const TargetInfo &Target,
984                                  const TargetInfo *AuxTarget) {
985  assert((!this->Target || this->Target == &Target) &&
986         "Incorrect target reinitialization");
987  assert(VoidTy.isNull() && "Context reinitialized?");
988
989  this->Target = &Target;
990  this->AuxTarget = AuxTarget;
991
992  ABI.reset(createCXXABI(Target));
993  AddrSpaceMap = getAddressSpaceMap(Target, LangOpts);
994  AddrSpaceMapMangling = isAddrSpaceMapManglingEnabled(Target, LangOpts);
995
996  // C99 6.2.5p19.
997  InitBuiltinType(VoidTy,              BuiltinType::Void);
998
999  // C99 6.2.5p2.
1000  InitBuiltinType(BoolTy,              BuiltinType::Bool);
1001  // C99 6.2.5p3.
1002  if (LangOpts.CharIsSigned)
1003    InitBuiltinType(CharTy,            BuiltinType::Char_S);
1004  else
1005    InitBuiltinType(CharTy,            BuiltinType::Char_U);
1006  // C99 6.2.5p4.
1007  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
1008  InitBuiltinType(ShortTy,             BuiltinType::Short);
1009  InitBuiltinType(IntTy,               BuiltinType::Int);
1010  InitBuiltinType(LongTy,              BuiltinType::Long);
1011  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
1012
1013  // C99 6.2.5p6.
1014  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
1015  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
1016  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
1017  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
1018  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
1019
1020  // C99 6.2.5p10.
1021  InitBuiltinType(FloatTy,             BuiltinType::Float);
1022  InitBuiltinType(DoubleTy,            BuiltinType::Double);
1023  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
1024
1025  // GNU extension, 128-bit integers.
1026  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
1027  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
1028
1029  // C++ 3.9.1p5
1030  if (TargetInfo::isTypeSigned(Target.getWCharType()))
1031    InitBuiltinType(WCharTy,           BuiltinType::WChar_S);
1032  else  // -fshort-wchar makes wchar_t be unsigned.
1033    InitBuiltinType(WCharTy,           BuiltinType::WChar_U);
1034  if (LangOpts.CPlusPlus && LangOpts.WChar)
1035    WideCharTy = WCharTy;
1036  else {
1037    // C99 (or C++ using -fno-wchar).
1038    WideCharTy = getFromTargetType(Target.getWCharType());
1039  }
1040
1041  WIntTy = getFromTargetType(Target.getWIntType());
1042
1043  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
1044    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
1045  else // C99
1046    Char16Ty = getFromTargetType(Target.getChar16Type());
1047
1048  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
1049    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
1050  else // C99
1051    Char32Ty = getFromTargetType(Target.getChar32Type());
1052
1053  // Placeholder type for type-dependent expressions whose type is
1054  // completely unknown. No code should ever check a type against
1055  // DependentTy and users should never see it; however, it is here to
1056  // help diagnose failures to properly check for type-dependent
1057  // expressions.
1058  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
1059
1060  // Placeholder type for functions.
1061  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
1062
1063  // Placeholder type for bound members.
1064  InitBuiltinType(BoundMemberTy,       BuiltinType::BoundMember);
1065
1066  // Placeholder type for pseudo-objects.
1067  InitBuiltinType(PseudoObjectTy,      BuiltinType::PseudoObject);
1068
1069  // "any" type; useful for debugger-like clients.
1070  InitBuiltinType(UnknownAnyTy,        BuiltinType::UnknownAny);
1071
1072  // Placeholder type for unbridged ARC casts.
1073  InitBuiltinType(ARCUnbridgedCastTy,  BuiltinType::ARCUnbridgedCast);
1074
1075  // Placeholder type for builtin functions.
1076  InitBuiltinType(BuiltinFnTy,  BuiltinType::BuiltinFn);
1077
1078  // Placeholder type for OMP array sections.
1079  if (LangOpts.OpenMP)
1080    InitBuiltinType(OMPArraySectionTy, BuiltinType::OMPArraySection);
1081
1082  // C99 6.2.5p11.
1083  FloatComplexTy      = getComplexType(FloatTy);
1084  DoubleComplexTy     = getComplexType(DoubleTy);
1085  LongDoubleComplexTy = getComplexType(LongDoubleTy);
1086
1087  // Builtin types for 'id', 'Class', and 'SEL'.
1088  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
1089  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
1090  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
1091
1092  if (LangOpts.OpenCL) {
1093    InitBuiltinType(OCLImage1dTy, BuiltinType::OCLImage1d);
1094    InitBuiltinType(OCLImage1dArrayTy, BuiltinType::OCLImage1dArray);
1095    InitBuiltinType(OCLImage1dBufferTy, BuiltinType::OCLImage1dBuffer);
1096    InitBuiltinType(OCLImage2dTy, BuiltinType::OCLImage2d);
1097    InitBuiltinType(OCLImage2dArrayTy, BuiltinType::OCLImage2dArray);
1098    InitBuiltinType(OCLImage2dDepthTy, BuiltinType::OCLImage2dDepth);
1099    InitBuiltinType(OCLImage2dArrayDepthTy, BuiltinType::OCLImage2dArrayDepth);
1100    InitBuiltinType(OCLImage2dMSAATy, BuiltinType::OCLImage2dMSAA);
1101    InitBuiltinType(OCLImage2dArrayMSAATy, BuiltinType::OCLImage2dArrayMSAA);
1102    InitBuiltinType(OCLImage2dMSAADepthTy, BuiltinType::OCLImage2dMSAADepth);
1103    InitBuiltinType(OCLImage2dArrayMSAADepthTy,
1104                    BuiltinType::OCLImage2dArrayMSAADepth);
1105    InitBuiltinType(OCLImage3dTy, BuiltinType::OCLImage3d);
1106
1107    InitBuiltinType(OCLSamplerTy, BuiltinType::OCLSampler);
1108    InitBuiltinType(OCLEventTy, BuiltinType::OCLEvent);
1109    InitBuiltinType(OCLClkEventTy, BuiltinType::OCLClkEvent);
1110    InitBuiltinType(OCLQueueTy, BuiltinType::OCLQueue);
1111    InitBuiltinType(OCLNDRangeTy, BuiltinType::OCLNDRange);
1112    InitBuiltinType(OCLReserveIDTy, BuiltinType::OCLReserveID);
1113  }
1114
1115  // Builtin type for __objc_yes and __objc_no
1116  ObjCBuiltinBoolTy = (Target.useSignedCharForObjCBool() ?
1117                       SignedCharTy : BoolTy);
1118
1119  ObjCConstantStringType = QualType();
1120
1121  ObjCSuperType = QualType();
1122
1123  // void * type
1124  VoidPtrTy = getPointerType(VoidTy);
1125
1126  // nullptr type (C++0x 2.14.7)
1127  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
1128
1129  // half type (OpenCL 6.1.1.1) / ARM NEON __fp16
1130  InitBuiltinType(HalfTy, BuiltinType::Half);
1131
1132  // Builtin type used to help define __builtin_va_list.
1133  VaListTagDecl = nullptr;
1134}
1135
1136DiagnosticsEngine &ASTContext::getDiagnostics() const {
1137  return SourceMgr.getDiagnostics();
1138}
1139
1140AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
1141  AttrVec *&Result = DeclAttrs[D];
1142  if (!Result) {
1143    void *Mem = Allocate(sizeof(AttrVec));
1144    Result = new (Mem) AttrVec;
1145  }
1146
1147  return *Result;
1148}
1149
1150/// \brief Erase the attributes corresponding to the given declaration.
1151void ASTContext::eraseDeclAttrs(const Decl *D) {
1152  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
1153  if (Pos != DeclAttrs.end()) {
1154    Pos->second->~AttrVec();
1155    DeclAttrs.erase(Pos);
1156  }
1157}
1158
1159// FIXME: Remove ?
1160MemberSpecializationInfo *
1161ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
1162  assert(Var->isStaticDataMember() && "Not a static data member");
1163  return getTemplateOrSpecializationInfo(Var)
1164      .dyn_cast<MemberSpecializationInfo *>();
1165}
1166
1167ASTContext::TemplateOrSpecializationInfo
1168ASTContext::getTemplateOrSpecializationInfo(const VarDecl *Var) {
1169  llvm::DenseMap<const VarDecl *, TemplateOrSpecializationInfo>::iterator Pos =
1170      TemplateOrInstantiation.find(Var);
1171  if (Pos == TemplateOrInstantiation.end())
1172    return TemplateOrSpecializationInfo();
1173
1174  return Pos->second;
1175}
1176
1177void
1178ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
1179                                                TemplateSpecializationKind TSK,
1180                                          SourceLocation PointOfInstantiation) {
1181  assert(Inst->isStaticDataMember() && "Not a static data member");
1182  assert(Tmpl->isStaticDataMember() && "Not a static data member");
1183  setTemplateOrSpecializationInfo(Inst, new (*this) MemberSpecializationInfo(
1184                                            Tmpl, TSK, PointOfInstantiation));
1185}
1186
1187void
1188ASTContext::setTemplateOrSpecializationInfo(VarDecl *Inst,
1189                                            TemplateOrSpecializationInfo TSI) {
1190  assert(!TemplateOrInstantiation[Inst] &&
1191         "Already noted what the variable was instantiated from");
1192  TemplateOrInstantiation[Inst] = TSI;
1193}
1194
1195FunctionDecl *ASTContext::getClassScopeSpecializationPattern(
1196                                                     const FunctionDecl *FD){
1197  assert(FD && "Specialization is 0");
1198  llvm::DenseMap<const FunctionDecl*, FunctionDecl *>::const_iterator Pos
1199    = ClassScopeSpecializationPattern.find(FD);
1200  if (Pos == ClassScopeSpecializationPattern.end())
1201    return nullptr;
1202
1203  return Pos->second;
1204}
1205
1206void ASTContext::setClassScopeSpecializationPattern(FunctionDecl *FD,
1207                                        FunctionDecl *Pattern) {
1208  assert(FD && "Specialization is 0");
1209  assert(Pattern && "Class scope specialization pattern is 0");
1210  ClassScopeSpecializationPattern[FD] = Pattern;
1211}
1212
1213NamedDecl *
1214ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
1215  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
1216    = InstantiatedFromUsingDecl.find(UUD);
1217  if (Pos == InstantiatedFromUsingDecl.end())
1218    return nullptr;
1219
1220  return Pos->second;
1221}
1222
1223void
1224ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
1225  assert((isa<UsingDecl>(Pattern) ||
1226          isa<UnresolvedUsingValueDecl>(Pattern) ||
1227          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
1228         "pattern decl is not a using decl");
1229  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
1230  InstantiatedFromUsingDecl[Inst] = Pattern;
1231}
1232
1233UsingShadowDecl *
1234ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
1235  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
1236    = InstantiatedFromUsingShadowDecl.find(Inst);
1237  if (Pos == InstantiatedFromUsingShadowDecl.end())
1238    return nullptr;
1239
1240  return Pos->second;
1241}
1242
1243void
1244ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
1245                                               UsingShadowDecl *Pattern) {
1246  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
1247  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
1248}
1249
1250FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
1251  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
1252    = InstantiatedFromUnnamedFieldDecl.find(Field);
1253  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
1254    return nullptr;
1255
1256  return Pos->second;
1257}
1258
1259void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
1260                                                     FieldDecl *Tmpl) {
1261  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
1262  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
1263  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
1264         "Already noted what unnamed field was instantiated from");
1265
1266  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
1267}
1268
1269ASTContext::overridden_cxx_method_iterator
1270ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
1271  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1272    = OverriddenMethods.find(Method->getCanonicalDecl());
1273  if (Pos == OverriddenMethods.end())
1274    return nullptr;
1275
1276  return Pos->second.begin();
1277}
1278
1279ASTContext::overridden_cxx_method_iterator
1280ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
1281  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1282    = OverriddenMethods.find(Method->getCanonicalDecl());
1283  if (Pos == OverriddenMethods.end())
1284    return nullptr;
1285
1286  return Pos->second.end();
1287}
1288
1289unsigned
1290ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
1291  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1292    = OverriddenMethods.find(Method->getCanonicalDecl());
1293  if (Pos == OverriddenMethods.end())
1294    return 0;
1295
1296  return Pos->second.size();
1297}
1298
1299void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
1300                                     const CXXMethodDecl *Overridden) {
1301  assert(Method->isCanonicalDecl() && Overridden->isCanonicalDecl());
1302  OverriddenMethods[Method].push_back(Overridden);
1303}
1304
1305void ASTContext::getOverriddenMethods(
1306                      const NamedDecl *D,
1307                      SmallVectorImpl<const NamedDecl *> &Overridden) const {
1308  assert(D);
1309
1310  if (const CXXMethodDecl *CXXMethod = dyn_cast<CXXMethodDecl>(D)) {
1311    Overridden.append(overridden_methods_begin(CXXMethod),
1312                      overridden_methods_end(CXXMethod));
1313    return;
1314  }
1315
1316  const ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(D);
1317  if (!Method)
1318    return;
1319
1320  SmallVector<const ObjCMethodDecl *, 8> OverDecls;
1321  Method->getOverriddenMethods(OverDecls);
1322  Overridden.append(OverDecls.begin(), OverDecls.end());
1323}
1324
1325void ASTContext::addedLocalImportDecl(ImportDecl *Import) {
1326  assert(!Import->NextLocalImport && "Import declaration already in the chain");
1327  assert(!Import->isFromASTFile() && "Non-local import declaration");
1328  if (!FirstLocalImport) {
1329    FirstLocalImport = Import;
1330    LastLocalImport = Import;
1331    return;
1332  }
1333
1334  LastLocalImport->NextLocalImport = Import;
1335  LastLocalImport = Import;
1336}
1337
1338//===----------------------------------------------------------------------===//
1339//                         Type Sizing and Analysis
1340//===----------------------------------------------------------------------===//
1341
1342/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
1343/// scalar floating point type.
1344const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
1345  const BuiltinType *BT = T->getAs<BuiltinType>();
1346  assert(BT && "Not a floating point type!");
1347  switch (BT->getKind()) {
1348  default: llvm_unreachable("Not a floating point type!");
1349  case BuiltinType::Half:       return Target->getHalfFormat();
1350  case BuiltinType::Float:      return Target->getFloatFormat();
1351  case BuiltinType::Double:     return Target->getDoubleFormat();
1352  case BuiltinType::LongDouble: return Target->getLongDoubleFormat();
1353  }
1354}
1355
1356CharUnits ASTContext::getDeclAlign(const Decl *D, bool ForAlignof) const {
1357  unsigned Align = Target->getCharWidth();
1358
1359  bool UseAlignAttrOnly = false;
1360  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
1361    Align = AlignFromAttr;
1362
1363    // __attribute__((aligned)) can increase or decrease alignment
1364    // *except* on a struct or struct member, where it only increases
1365    // alignment unless 'packed' is also specified.
1366    //
1367    // It is an error for alignas to decrease alignment, so we can
1368    // ignore that possibility;  Sema should diagnose it.
1369    if (isa<FieldDecl>(D)) {
1370      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
1371        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1372    } else {
1373      UseAlignAttrOnly = true;
1374    }
1375  }
1376  else if (isa<FieldDecl>(D))
1377      UseAlignAttrOnly =
1378        D->hasAttr<PackedAttr>() ||
1379        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1380
1381  // If we're using the align attribute only, just ignore everything
1382  // else about the declaration and its type.
1383  if (UseAlignAttrOnly) {
1384    // do nothing
1385
1386  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
1387    QualType T = VD->getType();
1388    if (const ReferenceType *RT = T->getAs<ReferenceType>()) {
1389      if (ForAlignof)
1390        T = RT->getPointeeType();
1391      else
1392        T = getPointerType(RT->getPointeeType());
1393    }
1394    QualType BaseT = getBaseElementType(T);
1395    if (!BaseT->isIncompleteType() && !T->isFunctionType()) {
1396      // Adjust alignments of declarations with array type by the
1397      // large-array alignment on the target.
1398      if (const ArrayType *arrayType = getAsArrayType(T)) {
1399        unsigned MinWidth = Target->getLargeArrayMinWidth();
1400        if (!ForAlignof && MinWidth) {
1401          if (isa<VariableArrayType>(arrayType))
1402            Align = std::max(Align, Target->getLargeArrayAlign());
1403          else if (isa<ConstantArrayType>(arrayType) &&
1404                   MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
1405            Align = std::max(Align, Target->getLargeArrayAlign());
1406        }
1407      }
1408      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
1409      if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1410        if (VD->hasGlobalStorage() && !ForAlignof)
1411          Align = std::max(Align, getTargetInfo().getMinGlobalAlign());
1412      }
1413    }
1414
1415    // Fields can be subject to extra alignment constraints, like if
1416    // the field is packed, the struct is packed, or the struct has a
1417    // a max-field-alignment constraint (#pragma pack).  So calculate
1418    // the actual alignment of the field within the struct, and then
1419    // (as we're expected to) constrain that by the alignment of the type.
1420    if (const FieldDecl *Field = dyn_cast<FieldDecl>(VD)) {
1421      const RecordDecl *Parent = Field->getParent();
1422      // We can only produce a sensible answer if the record is valid.
1423      if (!Parent->isInvalidDecl()) {
1424        const ASTRecordLayout &Layout = getASTRecordLayout(Parent);
1425
1426        // Start with the record's overall alignment.
1427        unsigned FieldAlign = toBits(Layout.getAlignment());
1428
1429        // Use the GCD of that and the offset within the record.
1430        uint64_t Offset = Layout.getFieldOffset(Field->getFieldIndex());
1431        if (Offset > 0) {
1432          // Alignment is always a power of 2, so the GCD will be a power of 2,
1433          // which means we get to do this crazy thing instead of Euclid's.
1434          uint64_t LowBitOfOffset = Offset & (~Offset + 1);
1435          if (LowBitOfOffset < FieldAlign)
1436            FieldAlign = static_cast<unsigned>(LowBitOfOffset);
1437        }
1438
1439        Align = std::min(Align, FieldAlign);
1440      }
1441    }
1442  }
1443
1444  return toCharUnitsFromBits(Align);
1445}
1446
1447// getTypeInfoDataSizeInChars - Return the size of a type, in
1448// chars. If the type is a record, its data size is returned.  This is
1449// the size of the memcpy that's performed when assigning this type
1450// using a trivial copy/move assignment operator.
1451std::pair<CharUnits, CharUnits>
1452ASTContext::getTypeInfoDataSizeInChars(QualType T) const {
1453  std::pair<CharUnits, CharUnits> sizeAndAlign = getTypeInfoInChars(T);
1454
1455  // In C++, objects can sometimes be allocated into the tail padding
1456  // of a base-class subobject.  We decide whether that's possible
1457  // during class layout, so here we can just trust the layout results.
1458  if (getLangOpts().CPlusPlus) {
1459    if (const RecordType *RT = T->getAs<RecordType>()) {
1460      const ASTRecordLayout &layout = getASTRecordLayout(RT->getDecl());
1461      sizeAndAlign.first = layout.getDataSize();
1462    }
1463  }
1464
1465  return sizeAndAlign;
1466}
1467
1468/// getConstantArrayInfoInChars - Performing the computation in CharUnits
1469/// instead of in bits prevents overflowing the uint64_t for some large arrays.
1470std::pair<CharUnits, CharUnits>
1471static getConstantArrayInfoInChars(const ASTContext &Context,
1472                                   const ConstantArrayType *CAT) {
1473  std::pair<CharUnits, CharUnits> EltInfo =
1474      Context.getTypeInfoInChars(CAT->getElementType());
1475  uint64_t Size = CAT->getSize().getZExtValue();
1476  assert((Size == 0 || static_cast<uint64_t>(EltInfo.first.getQuantity()) <=
1477              (uint64_t)(-1)/Size) &&
1478         "Overflow in array type char size evaluation");
1479  uint64_t Width = EltInfo.first.getQuantity() * Size;
1480  unsigned Align = EltInfo.second.getQuantity();
1481  if (!Context.getTargetInfo().getCXXABI().isMicrosoft() ||
1482      Context.getTargetInfo().getPointerWidth(0) == 64)
1483    Width = llvm::RoundUpToAlignment(Width, Align);
1484  return std::make_pair(CharUnits::fromQuantity(Width),
1485                        CharUnits::fromQuantity(Align));
1486}
1487
1488std::pair<CharUnits, CharUnits>
1489ASTContext::getTypeInfoInChars(const Type *T) const {
1490  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(T))
1491    return getConstantArrayInfoInChars(*this, CAT);
1492  TypeInfo Info = getTypeInfo(T);
1493  return std::make_pair(toCharUnitsFromBits(Info.Width),
1494                        toCharUnitsFromBits(Info.Align));
1495}
1496
1497std::pair<CharUnits, CharUnits>
1498ASTContext::getTypeInfoInChars(QualType T) const {
1499  return getTypeInfoInChars(T.getTypePtr());
1500}
1501
1502bool ASTContext::isAlignmentRequired(const Type *T) const {
1503  return getTypeInfo(T).AlignIsRequired;
1504}
1505
1506bool ASTContext::isAlignmentRequired(QualType T) const {
1507  return isAlignmentRequired(T.getTypePtr());
1508}
1509
1510TypeInfo ASTContext::getTypeInfo(const Type *T) const {
1511  TypeInfoMap::iterator I = MemoizedTypeInfo.find(T);
1512  if (I != MemoizedTypeInfo.end())
1513    return I->second;
1514
1515  // This call can invalidate MemoizedTypeInfo[T], so we need a second lookup.
1516  TypeInfo TI = getTypeInfoImpl(T);
1517  MemoizedTypeInfo[T] = TI;
1518  return TI;
1519}
1520
1521/// getTypeInfoImpl - Return the size of the specified type, in bits.  This
1522/// method does not work on incomplete types.
1523///
1524/// FIXME: Pointers into different addr spaces could have different sizes and
1525/// alignment requirements: getPointerInfo should take an AddrSpace, this
1526/// should take a QualType, &c.
1527TypeInfo ASTContext::getTypeInfoImpl(const Type *T) const {
1528  uint64_t Width = 0;
1529  unsigned Align = 8;
1530  bool AlignIsRequired = false;
1531  switch (T->getTypeClass()) {
1532#define TYPE(Class, Base)
1533#define ABSTRACT_TYPE(Class, Base)
1534#define NON_CANONICAL_TYPE(Class, Base)
1535#define DEPENDENT_TYPE(Class, Base) case Type::Class:
1536#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base)                       \
1537  case Type::Class:                                                            \
1538  assert(!T->isDependentType() && "should not see dependent types here");      \
1539  return getTypeInfo(cast<Class##Type>(T)->desugar().getTypePtr());
1540#include "clang/AST/TypeNodes.def"
1541    llvm_unreachable("Should not see dependent types");
1542
1543  case Type::FunctionNoProto:
1544  case Type::FunctionProto:
1545    // GCC extension: alignof(function) = 32 bits
1546    Width = 0;
1547    Align = 32;
1548    break;
1549
1550  case Type::IncompleteArray:
1551  case Type::VariableArray:
1552    Width = 0;
1553    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
1554    break;
1555
1556  case Type::ConstantArray: {
1557    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
1558
1559    TypeInfo EltInfo = getTypeInfo(CAT->getElementType());
1560    uint64_t Size = CAT->getSize().getZExtValue();
1561    assert((Size == 0 || EltInfo.Width <= (uint64_t)(-1) / Size) &&
1562           "Overflow in array type bit size evaluation");
1563    Width = EltInfo.Width * Size;
1564    Align = EltInfo.Align;
1565    if (!getTargetInfo().getCXXABI().isMicrosoft() ||
1566        getTargetInfo().getPointerWidth(0) == 64)
1567      Width = llvm::RoundUpToAlignment(Width, Align);
1568    break;
1569  }
1570  case Type::ExtVector:
1571  case Type::Vector: {
1572    const VectorType *VT = cast<VectorType>(T);
1573    TypeInfo EltInfo = getTypeInfo(VT->getElementType());
1574    Width = EltInfo.Width * VT->getNumElements();
1575    Align = Width;
1576    // If the alignment is not a power of 2, round up to the next power of 2.
1577    // This happens for non-power-of-2 length vectors.
1578    if (Align & (Align-1)) {
1579      Align = llvm::NextPowerOf2(Align);
1580      Width = llvm::RoundUpToAlignment(Width, Align);
1581    }
1582    // Adjust the alignment based on the target max.
1583    uint64_t TargetVectorAlign = Target->getMaxVectorAlign();
1584    if (TargetVectorAlign && TargetVectorAlign < Align)
1585      Align = TargetVectorAlign;
1586    break;
1587  }
1588
1589  case Type::Builtin:
1590    switch (cast<BuiltinType>(T)->getKind()) {
1591    default: llvm_unreachable("Unknown builtin type!");
1592    case BuiltinType::Void:
1593      // GCC extension: alignof(void) = 8 bits.
1594      Width = 0;
1595      Align = 8;
1596      break;
1597
1598    case BuiltinType::Bool:
1599      Width = Target->getBoolWidth();
1600      Align = Target->getBoolAlign();
1601      break;
1602    case BuiltinType::Char_S:
1603    case BuiltinType::Char_U:
1604    case BuiltinType::UChar:
1605    case BuiltinType::SChar:
1606      Width = Target->getCharWidth();
1607      Align = Target->getCharAlign();
1608      break;
1609    case BuiltinType::WChar_S:
1610    case BuiltinType::WChar_U:
1611      Width = Target->getWCharWidth();
1612      Align = Target->getWCharAlign();
1613      break;
1614    case BuiltinType::Char16:
1615      Width = Target->getChar16Width();
1616      Align = Target->getChar16Align();
1617      break;
1618    case BuiltinType::Char32:
1619      Width = Target->getChar32Width();
1620      Align = Target->getChar32Align();
1621      break;
1622    case BuiltinType::UShort:
1623    case BuiltinType::Short:
1624      Width = Target->getShortWidth();
1625      Align = Target->getShortAlign();
1626      break;
1627    case BuiltinType::UInt:
1628    case BuiltinType::Int:
1629      Width = Target->getIntWidth();
1630      Align = Target->getIntAlign();
1631      break;
1632    case BuiltinType::ULong:
1633    case BuiltinType::Long:
1634      Width = Target->getLongWidth();
1635      Align = Target->getLongAlign();
1636      break;
1637    case BuiltinType::ULongLong:
1638    case BuiltinType::LongLong:
1639      Width = Target->getLongLongWidth();
1640      Align = Target->getLongLongAlign();
1641      break;
1642    case BuiltinType::Int128:
1643    case BuiltinType::UInt128:
1644      Width = 128;
1645      Align = 128; // int128_t is 128-bit aligned on all targets.
1646      break;
1647    case BuiltinType::Half:
1648      Width = Target->getHalfWidth();
1649      Align = Target->getHalfAlign();
1650      break;
1651    case BuiltinType::Float:
1652      Width = Target->getFloatWidth();
1653      Align = Target->getFloatAlign();
1654      break;
1655    case BuiltinType::Double:
1656      Width = Target->getDoubleWidth();
1657      Align = Target->getDoubleAlign();
1658      break;
1659    case BuiltinType::LongDouble:
1660      Width = Target->getLongDoubleWidth();
1661      Align = Target->getLongDoubleAlign();
1662      break;
1663    case BuiltinType::NullPtr:
1664      Width = Target->getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
1665      Align = Target->getPointerAlign(0); //   == sizeof(void*)
1666      break;
1667    case BuiltinType::ObjCId:
1668    case BuiltinType::ObjCClass:
1669    case BuiltinType::ObjCSel:
1670      Width = Target->getPointerWidth(0);
1671      Align = Target->getPointerAlign(0);
1672      break;
1673    case BuiltinType::OCLSampler:
1674      // Samplers are modeled as integers.
1675      Width = Target->getIntWidth();
1676      Align = Target->getIntAlign();
1677      break;
1678    case BuiltinType::OCLEvent:
1679    case BuiltinType::OCLClkEvent:
1680    case BuiltinType::OCLQueue:
1681    case BuiltinType::OCLNDRange:
1682    case BuiltinType::OCLReserveID:
1683    case BuiltinType::OCLImage1d:
1684    case BuiltinType::OCLImage1dArray:
1685    case BuiltinType::OCLImage1dBuffer:
1686    case BuiltinType::OCLImage2d:
1687    case BuiltinType::OCLImage2dArray:
1688    case BuiltinType::OCLImage2dDepth:
1689    case BuiltinType::OCLImage2dArrayDepth:
1690    case BuiltinType::OCLImage2dMSAA:
1691    case BuiltinType::OCLImage2dArrayMSAA:
1692    case BuiltinType::OCLImage2dMSAADepth:
1693    case BuiltinType::OCLImage2dArrayMSAADepth:
1694    case BuiltinType::OCLImage3d:
1695      // Currently these types are pointers to opaque types.
1696      Width = Target->getPointerWidth(0);
1697      Align = Target->getPointerAlign(0);
1698      break;
1699    }
1700    break;
1701  case Type::ObjCObjectPointer:
1702    Width = Target->getPointerWidth(0);
1703    Align = Target->getPointerAlign(0);
1704    break;
1705  case Type::BlockPointer: {
1706    unsigned AS = getTargetAddressSpace(
1707        cast<BlockPointerType>(T)->getPointeeType());
1708    Width = Target->getPointerWidth(AS);
1709    Align = Target->getPointerAlign(AS);
1710    break;
1711  }
1712  case Type::LValueReference:
1713  case Type::RValueReference: {
1714    // alignof and sizeof should never enter this code path here, so we go
1715    // the pointer route.
1716    unsigned AS = getTargetAddressSpace(
1717        cast<ReferenceType>(T)->getPointeeType());
1718    Width = Target->getPointerWidth(AS);
1719    Align = Target->getPointerAlign(AS);
1720    break;
1721  }
1722  case Type::Pointer: {
1723    unsigned AS = getTargetAddressSpace(cast<PointerType>(T)->getPointeeType());
1724    Width = Target->getPointerWidth(AS);
1725    Align = Target->getPointerAlign(AS);
1726    break;
1727  }
1728  case Type::MemberPointer: {
1729    const MemberPointerType *MPT = cast<MemberPointerType>(T);
1730    std::tie(Width, Align) = ABI->getMemberPointerWidthAndAlign(MPT);
1731    break;
1732  }
1733  case Type::Complex: {
1734    // Complex types have the same alignment as their elements, but twice the
1735    // size.
1736    TypeInfo EltInfo = getTypeInfo(cast<ComplexType>(T)->getElementType());
1737    Width = EltInfo.Width * 2;
1738    Align = EltInfo.Align;
1739    break;
1740  }
1741  case Type::ObjCObject:
1742    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
1743  case Type::Adjusted:
1744  case Type::Decayed:
1745    return getTypeInfo(cast<AdjustedType>(T)->getAdjustedType().getTypePtr());
1746  case Type::ObjCInterface: {
1747    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
1748    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
1749    Width = toBits(Layout.getSize());
1750    Align = toBits(Layout.getAlignment());
1751    break;
1752  }
1753  case Type::Record:
1754  case Type::Enum: {
1755    const TagType *TT = cast<TagType>(T);
1756
1757    if (TT->getDecl()->isInvalidDecl()) {
1758      Width = 8;
1759      Align = 8;
1760      break;
1761    }
1762
1763    if (const EnumType *ET = dyn_cast<EnumType>(TT)) {
1764      const EnumDecl *ED = ET->getDecl();
1765      TypeInfo Info =
1766          getTypeInfo(ED->getIntegerType()->getUnqualifiedDesugaredType());
1767      if (unsigned AttrAlign = ED->getMaxAlignment()) {
1768        Info.Align = AttrAlign;
1769        Info.AlignIsRequired = true;
1770      }
1771      return Info;
1772    }
1773
1774    const RecordType *RT = cast<RecordType>(TT);
1775    const RecordDecl *RD = RT->getDecl();
1776    const ASTRecordLayout &Layout = getASTRecordLayout(RD);
1777    Width = toBits(Layout.getSize());
1778    Align = toBits(Layout.getAlignment());
1779    AlignIsRequired = RD->hasAttr<AlignedAttr>();
1780    break;
1781  }
1782
1783  case Type::SubstTemplateTypeParm:
1784    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
1785                       getReplacementType().getTypePtr());
1786
1787  case Type::Auto: {
1788    const AutoType *A = cast<AutoType>(T);
1789    assert(!A->getDeducedType().isNull() &&
1790           "cannot request the size of an undeduced or dependent auto type");
1791    return getTypeInfo(A->getDeducedType().getTypePtr());
1792  }
1793
1794  case Type::Paren:
1795    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
1796
1797  case Type::Typedef: {
1798    const TypedefNameDecl *Typedef = cast<TypedefType>(T)->getDecl();
1799    TypeInfo Info = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
1800    // If the typedef has an aligned attribute on it, it overrides any computed
1801    // alignment we have.  This violates the GCC documentation (which says that
1802    // attribute(aligned) can only round up) but matches its implementation.
1803    if (unsigned AttrAlign = Typedef->getMaxAlignment()) {
1804      Align = AttrAlign;
1805      AlignIsRequired = true;
1806    } else {
1807      Align = Info.Align;
1808      AlignIsRequired = Info.AlignIsRequired;
1809    }
1810    Width = Info.Width;
1811    break;
1812  }
1813
1814  case Type::Elaborated:
1815    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
1816
1817  case Type::Attributed:
1818    return getTypeInfo(
1819                  cast<AttributedType>(T)->getEquivalentType().getTypePtr());
1820
1821  case Type::Atomic: {
1822    // Start with the base type information.
1823    TypeInfo Info = getTypeInfo(cast<AtomicType>(T)->getValueType());
1824    Width = Info.Width;
1825    Align = Info.Align;
1826
1827    // If the size of the type doesn't exceed the platform's max
1828    // atomic promotion width, make the size and alignment more
1829    // favorable to atomic operations:
1830    if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth()) {
1831      // Round the size up to a power of 2.
1832      if (!llvm::isPowerOf2_64(Width))
1833        Width = llvm::NextPowerOf2(Width);
1834
1835      // Set the alignment equal to the size.
1836      Align = static_cast<unsigned>(Width);
1837    }
1838  }
1839  break;
1840
1841  case Type::Pipe: {
1842    TypeInfo Info = getTypeInfo(cast<PipeType>(T)->getElementType());
1843    Width = Info.Width;
1844    Align = Info.Align;
1845  }
1846
1847  }
1848
1849  assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
1850  return TypeInfo(Width, Align, AlignIsRequired);
1851}
1852
1853unsigned ASTContext::getOpenMPDefaultSimdAlign(QualType T) const {
1854  unsigned SimdAlign = getTargetInfo().getSimdDefaultAlign();
1855  // Target ppc64 with QPX: simd default alignment for pointer to double is 32.
1856  if ((getTargetInfo().getTriple().getArch() == llvm::Triple::ppc64 ||
1857       getTargetInfo().getTriple().getArch() == llvm::Triple::ppc64le) &&
1858      getTargetInfo().getABI() == "elfv1-qpx" &&
1859      T->isSpecificBuiltinType(BuiltinType::Double))
1860    SimdAlign = 256;
1861  return SimdAlign;
1862}
1863
1864/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1865CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1866  return CharUnits::fromQuantity(BitSize / getCharWidth());
1867}
1868
1869/// toBits - Convert a size in characters to a size in characters.
1870int64_t ASTContext::toBits(CharUnits CharSize) const {
1871  return CharSize.getQuantity() * getCharWidth();
1872}
1873
1874/// getTypeSizeInChars - Return the size of the specified type, in characters.
1875/// This method does not work on incomplete types.
1876CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1877  return getTypeInfoInChars(T).first;
1878}
1879CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1880  return getTypeInfoInChars(T).first;
1881}
1882
1883/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1884/// characters. This method does not work on incomplete types.
1885CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1886  return toCharUnitsFromBits(getTypeAlign(T));
1887}
1888CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1889  return toCharUnitsFromBits(getTypeAlign(T));
1890}
1891
1892/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1893/// type for the current target in bits.  This can be different than the ABI
1894/// alignment in cases where it is beneficial for performance to overalign
1895/// a data type.
1896unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1897  TypeInfo TI = getTypeInfo(T);
1898  unsigned ABIAlign = TI.Align;
1899
1900  T = T->getBaseElementTypeUnsafe();
1901
1902  // The preferred alignment of member pointers is that of a pointer.
1903  if (T->isMemberPointerType())
1904    return getPreferredTypeAlign(getPointerDiffType().getTypePtr());
1905
1906  if (Target->getTriple().getArch() == llvm::Triple::xcore)
1907    return ABIAlign;  // Never overalign on XCore.
1908
1909  // Double and long long should be naturally aligned if possible.
1910  if (const ComplexType *CT = T->getAs<ComplexType>())
1911    T = CT->getElementType().getTypePtr();
1912  if (const EnumType *ET = T->getAs<EnumType>())
1913    T = ET->getDecl()->getIntegerType().getTypePtr();
1914  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1915      T->isSpecificBuiltinType(BuiltinType::LongLong) ||
1916      T->isSpecificBuiltinType(BuiltinType::ULongLong))
1917    // Don't increase the alignment if an alignment attribute was specified on a
1918    // typedef declaration.
1919    if (!TI.AlignIsRequired)
1920      return std::max(ABIAlign, (unsigned)getTypeSize(T));
1921
1922  return ABIAlign;
1923}
1924
1925/// getTargetDefaultAlignForAttributeAligned - Return the default alignment
1926/// for __attribute__((aligned)) on this target, to be used if no alignment
1927/// value is specified.
1928unsigned ASTContext::getTargetDefaultAlignForAttributeAligned() const {
1929  return getTargetInfo().getDefaultAlignForAttributeAligned();
1930}
1931
1932/// getAlignOfGlobalVar - Return the alignment in bits that should be given
1933/// to a global variable of the specified type.
1934unsigned ASTContext::getAlignOfGlobalVar(QualType T) const {
1935  return std::max(getTypeAlign(T), getTargetInfo().getMinGlobalAlign());
1936}
1937
1938/// getAlignOfGlobalVarInChars - Return the alignment in characters that
1939/// should be given to a global variable of the specified type.
1940CharUnits ASTContext::getAlignOfGlobalVarInChars(QualType T) const {
1941  return toCharUnitsFromBits(getAlignOfGlobalVar(T));
1942}
1943
1944CharUnits ASTContext::getOffsetOfBaseWithVBPtr(const CXXRecordDecl *RD) const {
1945  CharUnits Offset = CharUnits::Zero();
1946  const ASTRecordLayout *Layout = &getASTRecordLayout(RD);
1947  while (const CXXRecordDecl *Base = Layout->getBaseSharingVBPtr()) {
1948    Offset += Layout->getBaseClassOffset(Base);
1949    Layout = &getASTRecordLayout(Base);
1950  }
1951  return Offset;
1952}
1953
1954/// DeepCollectObjCIvars -
1955/// This routine first collects all declared, but not synthesized, ivars in
1956/// super class and then collects all ivars, including those synthesized for
1957/// current class. This routine is used for implementation of current class
1958/// when all ivars, declared and synthesized are known.
1959///
1960void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1961                                      bool leafClass,
1962                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1963  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1964    DeepCollectObjCIvars(SuperClass, false, Ivars);
1965  if (!leafClass) {
1966    for (const auto *I : OI->ivars())
1967      Ivars.push_back(I);
1968  } else {
1969    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1970    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1971         Iv= Iv->getNextIvar())
1972      Ivars.push_back(Iv);
1973  }
1974}
1975
1976/// CollectInheritedProtocols - Collect all protocols in current class and
1977/// those inherited by it.
1978void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1979                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1980  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1981    // We can use protocol_iterator here instead of
1982    // all_referenced_protocol_iterator since we are walking all categories.
1983    for (auto *Proto : OI->all_referenced_protocols()) {
1984      CollectInheritedProtocols(Proto, Protocols);
1985    }
1986
1987    // Categories of this Interface.
1988    for (const auto *Cat : OI->visible_categories())
1989      CollectInheritedProtocols(Cat, Protocols);
1990
1991    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1992      while (SD) {
1993        CollectInheritedProtocols(SD, Protocols);
1994        SD = SD->getSuperClass();
1995      }
1996  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1997    for (auto *Proto : OC->protocols()) {
1998      CollectInheritedProtocols(Proto, Protocols);
1999    }
2000  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
2001    // Insert the protocol.
2002    if (!Protocols.insert(
2003          const_cast<ObjCProtocolDecl *>(OP->getCanonicalDecl())).second)
2004      return;
2005
2006    for (auto *Proto : OP->protocols())
2007      CollectInheritedProtocols(Proto, Protocols);
2008  }
2009}
2010
2011unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
2012  unsigned count = 0;
2013  // Count ivars declared in class extension.
2014  for (const auto *Ext : OI->known_extensions())
2015    count += Ext->ivar_size();
2016
2017  // Count ivar defined in this class's implementation.  This
2018  // includes synthesized ivars.
2019  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
2020    count += ImplDecl->ivar_size();
2021
2022  return count;
2023}
2024
2025bool ASTContext::isSentinelNullExpr(const Expr *E) {
2026  if (!E)
2027    return false;
2028
2029  // nullptr_t is always treated as null.
2030  if (E->getType()->isNullPtrType()) return true;
2031
2032  if (E->getType()->isAnyPointerType() &&
2033      E->IgnoreParenCasts()->isNullPointerConstant(*this,
2034                                                Expr::NPC_ValueDependentIsNull))
2035    return true;
2036
2037  // Unfortunately, __null has type 'int'.
2038  if (isa<GNUNullExpr>(E)) return true;
2039
2040  return false;
2041}
2042
2043/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
2044ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
2045  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
2046    I = ObjCImpls.find(D);
2047  if (I != ObjCImpls.end())
2048    return cast<ObjCImplementationDecl>(I->second);
2049  return nullptr;
2050}
2051/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
2052ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
2053  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
2054    I = ObjCImpls.find(D);
2055  if (I != ObjCImpls.end())
2056    return cast<ObjCCategoryImplDecl>(I->second);
2057  return nullptr;
2058}
2059
2060/// \brief Set the implementation of ObjCInterfaceDecl.
2061void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
2062                           ObjCImplementationDecl *ImplD) {
2063  assert(IFaceD && ImplD && "Passed null params");
2064  ObjCImpls[IFaceD] = ImplD;
2065}
2066/// \brief Set the implementation of ObjCCategoryDecl.
2067void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
2068                           ObjCCategoryImplDecl *ImplD) {
2069  assert(CatD && ImplD && "Passed null params");
2070  ObjCImpls[CatD] = ImplD;
2071}
2072
2073const ObjCMethodDecl *
2074ASTContext::getObjCMethodRedeclaration(const ObjCMethodDecl *MD) const {
2075  return ObjCMethodRedecls.lookup(MD);
2076}
2077
2078void ASTContext::setObjCMethodRedeclaration(const ObjCMethodDecl *MD,
2079                                            const ObjCMethodDecl *Redecl) {
2080  assert(!getObjCMethodRedeclaration(MD) && "MD already has a redeclaration");
2081  ObjCMethodRedecls[MD] = Redecl;
2082}
2083
2084const ObjCInterfaceDecl *ASTContext::getObjContainingInterface(
2085                                              const NamedDecl *ND) const {
2086  if (const ObjCInterfaceDecl *ID =
2087          dyn_cast<ObjCInterfaceDecl>(ND->getDeclContext()))
2088    return ID;
2089  if (const ObjCCategoryDecl *CD =
2090          dyn_cast<ObjCCategoryDecl>(ND->getDeclContext()))
2091    return CD->getClassInterface();
2092  if (const ObjCImplDecl *IMD =
2093          dyn_cast<ObjCImplDecl>(ND->getDeclContext()))
2094    return IMD->getClassInterface();
2095
2096  return nullptr;
2097}
2098
2099/// \brief Get the copy initialization expression of VarDecl,or NULL if
2100/// none exists.
2101Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
2102  assert(VD && "Passed null params");
2103  assert(VD->hasAttr<BlocksAttr>() &&
2104         "getBlockVarCopyInits - not __block var");
2105  llvm::DenseMap<const VarDecl*, Expr*>::iterator
2106    I = BlockVarCopyInits.find(VD);
2107  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : nullptr;
2108}
2109
2110/// \brief Set the copy inialization expression of a block var decl.
2111void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
2112  assert(VD && Init && "Passed null params");
2113  assert(VD->hasAttr<BlocksAttr>() &&
2114         "setBlockVarCopyInits - not __block var");
2115  BlockVarCopyInits[VD] = Init;
2116}
2117
2118TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
2119                                                 unsigned DataSize) const {
2120  if (!DataSize)
2121    DataSize = TypeLoc::getFullDataSizeForType(T);
2122  else
2123    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
2124           "incorrect data size provided to CreateTypeSourceInfo!");
2125
2126  TypeSourceInfo *TInfo =
2127    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
2128  new (TInfo) TypeSourceInfo(T);
2129  return TInfo;
2130}
2131
2132TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
2133                                                     SourceLocation L) const {
2134  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
2135  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
2136  return DI;
2137}
2138
2139const ASTRecordLayout &
2140ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
2141  return getObjCLayout(D, nullptr);
2142}
2143
2144const ASTRecordLayout &
2145ASTContext::getASTObjCImplementationLayout(
2146                                        const ObjCImplementationDecl *D) const {
2147  return getObjCLayout(D->getClassInterface(), D);
2148}
2149
2150//===----------------------------------------------------------------------===//
2151//                   Type creation/memoization methods
2152//===----------------------------------------------------------------------===//
2153
2154QualType
2155ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
2156  unsigned fastQuals = quals.getFastQualifiers();
2157  quals.removeFastQualifiers();
2158
2159  // Check if we've already instantiated this type.
2160  llvm::FoldingSetNodeID ID;
2161  ExtQuals::Profile(ID, baseType, quals);
2162  void *insertPos = nullptr;
2163  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
2164    assert(eq->getQualifiers() == quals);
2165    return QualType(eq, fastQuals);
2166  }
2167
2168  // If the base type is not canonical, make the appropriate canonical type.
2169  QualType canon;
2170  if (!baseType->isCanonicalUnqualified()) {
2171    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
2172    canonSplit.Quals.addConsistentQualifiers(quals);
2173    canon = getExtQualType(canonSplit.Ty, canonSplit.Quals);
2174
2175    // Re-find the insert position.
2176    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
2177  }
2178
2179  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
2180  ExtQualNodes.InsertNode(eq, insertPos);
2181  return QualType(eq, fastQuals);
2182}
2183
2184QualType
2185ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
2186  QualType CanT = getCanonicalType(T);
2187  if (CanT.getAddressSpace() == AddressSpace)
2188    return T;
2189
2190  // If we are composing extended qualifiers together, merge together
2191  // into one ExtQuals node.
2192  QualifierCollector Quals;
2193  const Type *TypeNode = Quals.strip(T);
2194
2195  // If this type already has an address space specified, it cannot get
2196  // another one.
2197  assert(!Quals.hasAddressSpace() &&
2198         "Type cannot be in multiple addr spaces!");
2199  Quals.addAddressSpace(AddressSpace);
2200
2201  return getExtQualType(TypeNode, Quals);
2202}
2203
2204QualType ASTContext::getObjCGCQualType(QualType T,
2205                                       Qualifiers::GC GCAttr) const {
2206  QualType CanT = getCanonicalType(T);
2207  if (CanT.getObjCGCAttr() == GCAttr)
2208    return T;
2209
2210  if (const PointerType *ptr = T->getAs<PointerType>()) {
2211    QualType Pointee = ptr->getPointeeType();
2212    if (Pointee->isAnyPointerType()) {
2213      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
2214      return getPointerType(ResultType);
2215    }
2216  }
2217
2218  // If we are composing extended qualifiers together, merge together
2219  // into one ExtQuals node.
2220  QualifierCollector Quals;
2221  const Type *TypeNode = Quals.strip(T);
2222
2223  // If this type already has an ObjCGC specified, it cannot get
2224  // another one.
2225  assert(!Quals.hasObjCGCAttr() &&
2226         "Type cannot have multiple ObjCGCs!");
2227  Quals.addObjCGCAttr(GCAttr);
2228
2229  return getExtQualType(TypeNode, Quals);
2230}
2231
2232const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
2233                                                   FunctionType::ExtInfo Info) {
2234  if (T->getExtInfo() == Info)
2235    return T;
2236
2237  QualType Result;
2238  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
2239    Result = getFunctionNoProtoType(FNPT->getReturnType(), Info);
2240  } else {
2241    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
2242    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
2243    EPI.ExtInfo = Info;
2244    Result = getFunctionType(FPT->getReturnType(), FPT->getParamTypes(), EPI);
2245  }
2246
2247  return cast<FunctionType>(Result.getTypePtr());
2248}
2249
2250void ASTContext::adjustDeducedFunctionResultType(FunctionDecl *FD,
2251                                                 QualType ResultType) {
2252  FD = FD->getMostRecentDecl();
2253  while (true) {
2254    const FunctionProtoType *FPT = FD->getType()->castAs<FunctionProtoType>();
2255    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
2256    FD->setType(getFunctionType(ResultType, FPT->getParamTypes(), EPI));
2257    if (FunctionDecl *Next = FD->getPreviousDecl())
2258      FD = Next;
2259    else
2260      break;
2261  }
2262  if (ASTMutationListener *L = getASTMutationListener())
2263    L->DeducedReturnType(FD, ResultType);
2264}
2265
2266/// Get a function type and produce the equivalent function type with the
2267/// specified exception specification. Type sugar that can be present on a
2268/// declaration of a function with an exception specification is permitted
2269/// and preserved. Other type sugar (for instance, typedefs) is not.
2270static QualType getFunctionTypeWithExceptionSpec(
2271    ASTContext &Context, QualType Orig,
2272    const FunctionProtoType::ExceptionSpecInfo &ESI) {
2273  // Might have some parens.
2274  if (auto *PT = dyn_cast<ParenType>(Orig))
2275    return Context.getParenType(
2276        getFunctionTypeWithExceptionSpec(Context, PT->getInnerType(), ESI));
2277
2278  // Might have a calling-convention attribute.
2279  if (auto *AT = dyn_cast<AttributedType>(Orig))
2280    return Context.getAttributedType(
2281        AT->getAttrKind(),
2282        getFunctionTypeWithExceptionSpec(Context, AT->getModifiedType(), ESI),
2283        getFunctionTypeWithExceptionSpec(Context, AT->getEquivalentType(),
2284                                         ESI));
2285
2286  // Anything else must be a function type. Rebuild it with the new exception
2287  // specification.
2288  const FunctionProtoType *Proto = cast<FunctionProtoType>(Orig);
2289  return Context.getFunctionType(
2290      Proto->getReturnType(), Proto->getParamTypes(),
2291      Proto->getExtProtoInfo().withExceptionSpec(ESI));
2292}
2293
2294void ASTContext::adjustExceptionSpec(
2295    FunctionDecl *FD, const FunctionProtoType::ExceptionSpecInfo &ESI,
2296    bool AsWritten) {
2297  // Update the type.
2298  QualType Updated =
2299      getFunctionTypeWithExceptionSpec(*this, FD->getType(), ESI);
2300  FD->setType(Updated);
2301
2302  if (!AsWritten)
2303    return;
2304
2305  // Update the type in the type source information too.
2306  if (TypeSourceInfo *TSInfo = FD->getTypeSourceInfo()) {
2307    // If the type and the type-as-written differ, we may need to update
2308    // the type-as-written too.
2309    if (TSInfo->getType() != FD->getType())
2310      Updated = getFunctionTypeWithExceptionSpec(*this, TSInfo->getType(), ESI);
2311
2312    // FIXME: When we get proper type location information for exceptions,
2313    // we'll also have to rebuild the TypeSourceInfo. For now, we just patch
2314    // up the TypeSourceInfo;
2315    assert(TypeLoc::getFullDataSizeForType(Updated) ==
2316               TypeLoc::getFullDataSizeForType(TSInfo->getType()) &&
2317           "TypeLoc size mismatch from updating exception specification");
2318    TSInfo->overrideType(Updated);
2319  }
2320}
2321
2322/// getComplexType - Return the uniqued reference to the type for a complex
2323/// number with the specified element type.
2324QualType ASTContext::getComplexType(QualType T) const {
2325  // Unique pointers, to guarantee there is only one pointer of a particular
2326  // structure.
2327  llvm::FoldingSetNodeID ID;
2328  ComplexType::Profile(ID, T);
2329
2330  void *InsertPos = nullptr;
2331  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
2332    return QualType(CT, 0);
2333
2334  // If the pointee type isn't canonical, this won't be a canonical type either,
2335  // so fill in the canonical type field.
2336  QualType Canonical;
2337  if (!T.isCanonical()) {
2338    Canonical = getComplexType(getCanonicalType(T));
2339
2340    // Get the new insert position for the node we care about.
2341    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
2342    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2343  }
2344  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
2345  Types.push_back(New);
2346  ComplexTypes.InsertNode(New, InsertPos);
2347  return QualType(New, 0);
2348}
2349
2350/// getPointerType - Return the uniqued reference to the type for a pointer to
2351/// the specified type.
2352QualType ASTContext::getPointerType(QualType T) const {
2353  // Unique pointers, to guarantee there is only one pointer of a particular
2354  // structure.
2355  llvm::FoldingSetNodeID ID;
2356  PointerType::Profile(ID, T);
2357
2358  void *InsertPos = nullptr;
2359  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2360    return QualType(PT, 0);
2361
2362  // If the pointee type isn't canonical, this won't be a canonical type either,
2363  // so fill in the canonical type field.
2364  QualType Canonical;
2365  if (!T.isCanonical()) {
2366    Canonical = getPointerType(getCanonicalType(T));
2367
2368    // Get the new insert position for the node we care about.
2369    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2370    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2371  }
2372  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
2373  Types.push_back(New);
2374  PointerTypes.InsertNode(New, InsertPos);
2375  return QualType(New, 0);
2376}
2377
2378QualType ASTContext::getAdjustedType(QualType Orig, QualType New) const {
2379  llvm::FoldingSetNodeID ID;
2380  AdjustedType::Profile(ID, Orig, New);
2381  void *InsertPos = nullptr;
2382  AdjustedType *AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
2383  if (AT)
2384    return QualType(AT, 0);
2385
2386  QualType Canonical = getCanonicalType(New);
2387
2388  // Get the new insert position for the node we care about.
2389  AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
2390  assert(!AT && "Shouldn't be in the map!");
2391
2392  AT = new (*this, TypeAlignment)
2393      AdjustedType(Type::Adjusted, Orig, New, Canonical);
2394  Types.push_back(AT);
2395  AdjustedTypes.InsertNode(AT, InsertPos);
2396  return QualType(AT, 0);
2397}
2398
2399QualType ASTContext::getDecayedType(QualType T) const {
2400  assert((T->isArrayType() || T->isFunctionType()) && "T does not decay");
2401
2402  QualType Decayed;
2403
2404  // C99 6.7.5.3p7:
2405  //   A declaration of a parameter as "array of type" shall be
2406  //   adjusted to "qualified pointer to type", where the type
2407  //   qualifiers (if any) are those specified within the [ and ] of
2408  //   the array type derivation.
2409  if (T->isArrayType())
2410    Decayed = getArrayDecayedType(T);
2411
2412  // C99 6.7.5.3p8:
2413  //   A declaration of a parameter as "function returning type"
2414  //   shall be adjusted to "pointer to function returning type", as
2415  //   in 6.3.2.1.
2416  if (T->isFunctionType())
2417    Decayed = getPointerType(T);
2418
2419  llvm::FoldingSetNodeID ID;
2420  AdjustedType::Profile(ID, T, Decayed);
2421  void *InsertPos = nullptr;
2422  AdjustedType *AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
2423  if (AT)
2424    return QualType(AT, 0);
2425
2426  QualType Canonical = getCanonicalType(Decayed);
2427
2428  // Get the new insert position for the node we care about.
2429  AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
2430  assert(!AT && "Shouldn't be in the map!");
2431
2432  AT = new (*this, TypeAlignment) DecayedType(T, Decayed, Canonical);
2433  Types.push_back(AT);
2434  AdjustedTypes.InsertNode(AT, InsertPos);
2435  return QualType(AT, 0);
2436}
2437
2438/// getBlockPointerType - Return the uniqued reference to the type for
2439/// a pointer to the specified block.
2440QualType ASTContext::getBlockPointerType(QualType T) const {
2441  assert(T->isFunctionType() && "block of function types only");
2442  // Unique pointers, to guarantee there is only one block of a particular
2443  // structure.
2444  llvm::FoldingSetNodeID ID;
2445  BlockPointerType::Profile(ID, T);
2446
2447  void *InsertPos = nullptr;
2448  if (BlockPointerType *PT =
2449        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2450    return QualType(PT, 0);
2451
2452  // If the block pointee type isn't canonical, this won't be a canonical
2453  // type either so fill in the canonical type field.
2454  QualType Canonical;
2455  if (!T.isCanonical()) {
2456    Canonical = getBlockPointerType(getCanonicalType(T));
2457
2458    // Get the new insert position for the node we care about.
2459    BlockPointerType *NewIP =
2460      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2461    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2462  }
2463  BlockPointerType *New
2464    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
2465  Types.push_back(New);
2466  BlockPointerTypes.InsertNode(New, InsertPos);
2467  return QualType(New, 0);
2468}
2469
2470/// getLValueReferenceType - Return the uniqued reference to the type for an
2471/// lvalue reference to the specified type.
2472QualType
2473ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
2474  assert(getCanonicalType(T) != OverloadTy &&
2475         "Unresolved overloaded function type");
2476
2477  // Unique pointers, to guarantee there is only one pointer of a particular
2478  // structure.
2479  llvm::FoldingSetNodeID ID;
2480  ReferenceType::Profile(ID, T, SpelledAsLValue);
2481
2482  void *InsertPos = nullptr;
2483  if (LValueReferenceType *RT =
2484        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
2485    return QualType(RT, 0);
2486
2487  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
2488
2489  // If the referencee type isn't canonical, this won't be a canonical type
2490  // either, so fill in the canonical type field.
2491  QualType Canonical;
2492  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
2493    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
2494    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
2495
2496    // Get the new insert position for the node we care about.
2497    LValueReferenceType *NewIP =
2498      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
2499    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2500  }
2501
2502  LValueReferenceType *New
2503    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
2504                                                     SpelledAsLValue);
2505  Types.push_back(New);
2506  LValueReferenceTypes.InsertNode(New, InsertPos);
2507
2508  return QualType(New, 0);
2509}
2510
2511/// getRValueReferenceType - Return the uniqued reference to the type for an
2512/// rvalue reference to the specified type.
2513QualType ASTContext::getRValueReferenceType(QualType T) const {
2514  // Unique pointers, to guarantee there is only one pointer of a particular
2515  // structure.
2516  llvm::FoldingSetNodeID ID;
2517  ReferenceType::Profile(ID, T, false);
2518
2519  void *InsertPos = nullptr;
2520  if (RValueReferenceType *RT =
2521        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
2522    return QualType(RT, 0);
2523
2524  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
2525
2526  // If the referencee type isn't canonical, this won't be a canonical type
2527  // either, so fill in the canonical type field.
2528  QualType Canonical;
2529  if (InnerRef || !T.isCanonical()) {
2530    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
2531    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
2532
2533    // Get the new insert position for the node we care about.
2534    RValueReferenceType *NewIP =
2535      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
2536    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2537  }
2538
2539  RValueReferenceType *New
2540    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
2541  Types.push_back(New);
2542  RValueReferenceTypes.InsertNode(New, InsertPos);
2543  return QualType(New, 0);
2544}
2545
2546/// getMemberPointerType - Return the uniqued reference to the type for a
2547/// member pointer to the specified type, in the specified class.
2548QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
2549  // Unique pointers, to guarantee there is only one pointer of a particular
2550  // structure.
2551  llvm::FoldingSetNodeID ID;
2552  MemberPointerType::Profile(ID, T, Cls);
2553
2554  void *InsertPos = nullptr;
2555  if (MemberPointerType *PT =
2556      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2557    return QualType(PT, 0);
2558
2559  // If the pointee or class type isn't canonical, this won't be a canonical
2560  // type either, so fill in the canonical type field.
2561  QualType Canonical;
2562  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
2563    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
2564
2565    // Get the new insert position for the node we care about.
2566    MemberPointerType *NewIP =
2567      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2568    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2569  }
2570  MemberPointerType *New
2571    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
2572  Types.push_back(New);
2573  MemberPointerTypes.InsertNode(New, InsertPos);
2574  return QualType(New, 0);
2575}
2576
2577/// getConstantArrayType - Return the unique reference to the type for an
2578/// array of the specified element type.
2579QualType ASTContext::getConstantArrayType(QualType EltTy,
2580                                          const llvm::APInt &ArySizeIn,
2581                                          ArrayType::ArraySizeModifier ASM,
2582                                          unsigned IndexTypeQuals) const {
2583  assert((EltTy->isDependentType() ||
2584          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
2585         "Constant array of VLAs is illegal!");
2586
2587  // Convert the array size into a canonical width matching the pointer size for
2588  // the target.
2589  llvm::APInt ArySize(ArySizeIn);
2590  ArySize =
2591    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
2592
2593  llvm::FoldingSetNodeID ID;
2594  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
2595
2596  void *InsertPos = nullptr;
2597  if (ConstantArrayType *ATP =
2598      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
2599    return QualType(ATP, 0);
2600
2601  // If the element type isn't canonical or has qualifiers, this won't
2602  // be a canonical type either, so fill in the canonical type field.
2603  QualType Canon;
2604  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2605    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2606    Canon = getConstantArrayType(QualType(canonSplit.Ty, 0), ArySize,
2607                                 ASM, IndexTypeQuals);
2608    Canon = getQualifiedType(Canon, canonSplit.Quals);
2609
2610    // Get the new insert position for the node we care about.
2611    ConstantArrayType *NewIP =
2612      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
2613    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2614  }
2615
2616  ConstantArrayType *New = new(*this,TypeAlignment)
2617    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
2618  ConstantArrayTypes.InsertNode(New, InsertPos);
2619  Types.push_back(New);
2620  return QualType(New, 0);
2621}
2622
2623/// getVariableArrayDecayedType - Turns the given type, which may be
2624/// variably-modified, into the corresponding type with all the known
2625/// sizes replaced with [*].
2626QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
2627  // Vastly most common case.
2628  if (!type->isVariablyModifiedType()) return type;
2629
2630  QualType result;
2631
2632  SplitQualType split = type.getSplitDesugaredType();
2633  const Type *ty = split.Ty;
2634  switch (ty->getTypeClass()) {
2635#define TYPE(Class, Base)
2636#define ABSTRACT_TYPE(Class, Base)
2637#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
2638#include "clang/AST/TypeNodes.def"
2639    llvm_unreachable("didn't desugar past all non-canonical types?");
2640
2641  // These types should never be variably-modified.
2642  case Type::Builtin:
2643  case Type::Complex:
2644  case Type::Vector:
2645  case Type::ExtVector:
2646  case Type::DependentSizedExtVector:
2647  case Type::ObjCObject:
2648  case Type::ObjCInterface:
2649  case Type::ObjCObjectPointer:
2650  case Type::Record:
2651  case Type::Enum:
2652  case Type::UnresolvedUsing:
2653  case Type::TypeOfExpr:
2654  case Type::TypeOf:
2655  case Type::Decltype:
2656  case Type::UnaryTransform:
2657  case Type::DependentName:
2658  case Type::InjectedClassName:
2659  case Type::TemplateSpecialization:
2660  case Type::DependentTemplateSpecialization:
2661  case Type::TemplateTypeParm:
2662  case Type::SubstTemplateTypeParmPack:
2663  case Type::Auto:
2664  case Type::PackExpansion:
2665    llvm_unreachable("type should never be variably-modified");
2666
2667  // These types can be variably-modified but should never need to
2668  // further decay.
2669  case Type::FunctionNoProto:
2670  case Type::FunctionProto:
2671  case Type::BlockPointer:
2672  case Type::MemberPointer:
2673  case Type::Pipe:
2674    return type;
2675
2676  // These types can be variably-modified.  All these modifications
2677  // preserve structure except as noted by comments.
2678  // TODO: if we ever care about optimizing VLAs, there are no-op
2679  // optimizations available here.
2680  case Type::Pointer:
2681    result = getPointerType(getVariableArrayDecayedType(
2682                              cast<PointerType>(ty)->getPointeeType()));
2683    break;
2684
2685  case Type::LValueReference: {
2686    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
2687    result = getLValueReferenceType(
2688                 getVariableArrayDecayedType(lv->getPointeeType()),
2689                                    lv->isSpelledAsLValue());
2690    break;
2691  }
2692
2693  case Type::RValueReference: {
2694    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
2695    result = getRValueReferenceType(
2696                 getVariableArrayDecayedType(lv->getPointeeType()));
2697    break;
2698  }
2699
2700  case Type::Atomic: {
2701    const AtomicType *at = cast<AtomicType>(ty);
2702    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
2703    break;
2704  }
2705
2706  case Type::ConstantArray: {
2707    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
2708    result = getConstantArrayType(
2709                 getVariableArrayDecayedType(cat->getElementType()),
2710                                  cat->getSize(),
2711                                  cat->getSizeModifier(),
2712                                  cat->getIndexTypeCVRQualifiers());
2713    break;
2714  }
2715
2716  case Type::DependentSizedArray: {
2717    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
2718    result = getDependentSizedArrayType(
2719                 getVariableArrayDecayedType(dat->getElementType()),
2720                                        dat->getSizeExpr(),
2721                                        dat->getSizeModifier(),
2722                                        dat->getIndexTypeCVRQualifiers(),
2723                                        dat->getBracketsRange());
2724    break;
2725  }
2726
2727  // Turn incomplete types into [*] types.
2728  case Type::IncompleteArray: {
2729    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
2730    result = getVariableArrayType(
2731                 getVariableArrayDecayedType(iat->getElementType()),
2732                                  /*size*/ nullptr,
2733                                  ArrayType::Normal,
2734                                  iat->getIndexTypeCVRQualifiers(),
2735                                  SourceRange());
2736    break;
2737  }
2738
2739  // Turn VLA types into [*] types.
2740  case Type::VariableArray: {
2741    const VariableArrayType *vat = cast<VariableArrayType>(ty);
2742    result = getVariableArrayType(
2743                 getVariableArrayDecayedType(vat->getElementType()),
2744                                  /*size*/ nullptr,
2745                                  ArrayType::Star,
2746                                  vat->getIndexTypeCVRQualifiers(),
2747                                  vat->getBracketsRange());
2748    break;
2749  }
2750  }
2751
2752  // Apply the top-level qualifiers from the original.
2753  return getQualifiedType(result, split.Quals);
2754}
2755
2756/// getVariableArrayType - Returns a non-unique reference to the type for a
2757/// variable array of the specified element type.
2758QualType ASTContext::getVariableArrayType(QualType EltTy,
2759                                          Expr *NumElts,
2760                                          ArrayType::ArraySizeModifier ASM,
2761                                          unsigned IndexTypeQuals,
2762                                          SourceRange Brackets) const {
2763  // Since we don't unique expressions, it isn't possible to unique VLA's
2764  // that have an expression provided for their size.
2765  QualType Canon;
2766
2767  // Be sure to pull qualifiers off the element type.
2768  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2769    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2770    Canon = getVariableArrayType(QualType(canonSplit.Ty, 0), NumElts, ASM,
2771                                 IndexTypeQuals, Brackets);
2772    Canon = getQualifiedType(Canon, canonSplit.Quals);
2773  }
2774
2775  VariableArrayType *New = new(*this, TypeAlignment)
2776    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
2777
2778  VariableArrayTypes.push_back(New);
2779  Types.push_back(New);
2780  return QualType(New, 0);
2781}
2782
2783/// getDependentSizedArrayType - Returns a non-unique reference to
2784/// the type for a dependently-sized array of the specified element
2785/// type.
2786QualType ASTContext::getDependentSizedArrayType(QualType elementType,
2787                                                Expr *numElements,
2788                                                ArrayType::ArraySizeModifier ASM,
2789                                                unsigned elementTypeQuals,
2790                                                SourceRange brackets) const {
2791  assert((!numElements || numElements->isTypeDependent() ||
2792          numElements->isValueDependent()) &&
2793         "Size must be type- or value-dependent!");
2794
2795  // Dependently-sized array types that do not have a specified number
2796  // of elements will have their sizes deduced from a dependent
2797  // initializer.  We do no canonicalization here at all, which is okay
2798  // because they can't be used in most locations.
2799  if (!numElements) {
2800    DependentSizedArrayType *newType
2801      = new (*this, TypeAlignment)
2802          DependentSizedArrayType(*this, elementType, QualType(),
2803                                  numElements, ASM, elementTypeQuals,
2804                                  brackets);
2805    Types.push_back(newType);
2806    return QualType(newType, 0);
2807  }
2808
2809  // Otherwise, we actually build a new type every time, but we
2810  // also build a canonical type.
2811
2812  SplitQualType canonElementType = getCanonicalType(elementType).split();
2813
2814  void *insertPos = nullptr;
2815  llvm::FoldingSetNodeID ID;
2816  DependentSizedArrayType::Profile(ID, *this,
2817                                   QualType(canonElementType.Ty, 0),
2818                                   ASM, elementTypeQuals, numElements);
2819
2820  // Look for an existing type with these properties.
2821  DependentSizedArrayType *canonTy =
2822    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2823
2824  // If we don't have one, build one.
2825  if (!canonTy) {
2826    canonTy = new (*this, TypeAlignment)
2827      DependentSizedArrayType(*this, QualType(canonElementType.Ty, 0),
2828                              QualType(), numElements, ASM, elementTypeQuals,
2829                              brackets);
2830    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
2831    Types.push_back(canonTy);
2832  }
2833
2834  // Apply qualifiers from the element type to the array.
2835  QualType canon = getQualifiedType(QualType(canonTy,0),
2836                                    canonElementType.Quals);
2837
2838  // If we didn't need extra canonicalization for the element type or the size
2839  // expression, then just use that as our result.
2840  if (QualType(canonElementType.Ty, 0) == elementType &&
2841      canonTy->getSizeExpr() == numElements)
2842    return canon;
2843
2844  // Otherwise, we need to build a type which follows the spelling
2845  // of the element type.
2846  DependentSizedArrayType *sugaredType
2847    = new (*this, TypeAlignment)
2848        DependentSizedArrayType(*this, elementType, canon, numElements,
2849                                ASM, elementTypeQuals, brackets);
2850  Types.push_back(sugaredType);
2851  return QualType(sugaredType, 0);
2852}
2853
2854QualType ASTContext::getIncompleteArrayType(QualType elementType,
2855                                            ArrayType::ArraySizeModifier ASM,
2856                                            unsigned elementTypeQuals) const {
2857  llvm::FoldingSetNodeID ID;
2858  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
2859
2860  void *insertPos = nullptr;
2861  if (IncompleteArrayType *iat =
2862       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
2863    return QualType(iat, 0);
2864
2865  // If the element type isn't canonical, this won't be a canonical type
2866  // either, so fill in the canonical type field.  We also have to pull
2867  // qualifiers off the element type.
2868  QualType canon;
2869
2870  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
2871    SplitQualType canonSplit = getCanonicalType(elementType).split();
2872    canon = getIncompleteArrayType(QualType(canonSplit.Ty, 0),
2873                                   ASM, elementTypeQuals);
2874    canon = getQualifiedType(canon, canonSplit.Quals);
2875
2876    // Get the new insert position for the node we care about.
2877    IncompleteArrayType *existing =
2878      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2879    assert(!existing && "Shouldn't be in the map!"); (void) existing;
2880  }
2881
2882  IncompleteArrayType *newType = new (*this, TypeAlignment)
2883    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
2884
2885  IncompleteArrayTypes.InsertNode(newType, insertPos);
2886  Types.push_back(newType);
2887  return QualType(newType, 0);
2888}
2889
2890/// getVectorType - Return the unique reference to a vector type of
2891/// the specified element type and size. VectorType must be a built-in type.
2892QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
2893                                   VectorType::VectorKind VecKind) const {
2894  assert(vecType->isBuiltinType());
2895
2896  // Check if we've already instantiated a vector of this type.
2897  llvm::FoldingSetNodeID ID;
2898  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
2899
2900  void *InsertPos = nullptr;
2901  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2902    return QualType(VTP, 0);
2903
2904  // If the element type isn't canonical, this won't be a canonical type either,
2905  // so fill in the canonical type field.
2906  QualType Canonical;
2907  if (!vecType.isCanonical()) {
2908    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
2909
2910    // Get the new insert position for the node we care about.
2911    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2912    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2913  }
2914  VectorType *New = new (*this, TypeAlignment)
2915    VectorType(vecType, NumElts, Canonical, VecKind);
2916  VectorTypes.InsertNode(New, InsertPos);
2917  Types.push_back(New);
2918  return QualType(New, 0);
2919}
2920
2921/// getExtVectorType - Return the unique reference to an extended vector type of
2922/// the specified element type and size. VectorType must be a built-in type.
2923QualType
2924ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
2925  assert(vecType->isBuiltinType() || vecType->isDependentType());
2926
2927  // Check if we've already instantiated a vector of this type.
2928  llvm::FoldingSetNodeID ID;
2929  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
2930                      VectorType::GenericVector);
2931  void *InsertPos = nullptr;
2932  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2933    return QualType(VTP, 0);
2934
2935  // If the element type isn't canonical, this won't be a canonical type either,
2936  // so fill in the canonical type field.
2937  QualType Canonical;
2938  if (!vecType.isCanonical()) {
2939    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
2940
2941    // Get the new insert position for the node we care about.
2942    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2943    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2944  }
2945  ExtVectorType *New = new (*this, TypeAlignment)
2946    ExtVectorType(vecType, NumElts, Canonical);
2947  VectorTypes.InsertNode(New, InsertPos);
2948  Types.push_back(New);
2949  return QualType(New, 0);
2950}
2951
2952QualType
2953ASTContext::getDependentSizedExtVectorType(QualType vecType,
2954                                           Expr *SizeExpr,
2955                                           SourceLocation AttrLoc) const {
2956  llvm::FoldingSetNodeID ID;
2957  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
2958                                       SizeExpr);
2959
2960  void *InsertPos = nullptr;
2961  DependentSizedExtVectorType *Canon
2962    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2963  DependentSizedExtVectorType *New;
2964  if (Canon) {
2965    // We already have a canonical version of this array type; use it as
2966    // the canonical type for a newly-built type.
2967    New = new (*this, TypeAlignment)
2968      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
2969                                  SizeExpr, AttrLoc);
2970  } else {
2971    QualType CanonVecTy = getCanonicalType(vecType);
2972    if (CanonVecTy == vecType) {
2973      New = new (*this, TypeAlignment)
2974        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
2975                                    AttrLoc);
2976
2977      DependentSizedExtVectorType *CanonCheck
2978        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2979      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
2980      (void)CanonCheck;
2981      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
2982    } else {
2983      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
2984                                                      SourceLocation());
2985      New = new (*this, TypeAlignment)
2986        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2987    }
2988  }
2989
2990  Types.push_back(New);
2991  return QualType(New, 0);
2992}
2993
2994/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
2995///
2996QualType
2997ASTContext::getFunctionNoProtoType(QualType ResultTy,
2998                                   const FunctionType::ExtInfo &Info) const {
2999  const CallingConv CallConv = Info.getCC();
3000
3001  // Unique functions, to guarantee there is only one function of a particular
3002  // structure.
3003  llvm::FoldingSetNodeID ID;
3004  FunctionNoProtoType::Profile(ID, ResultTy, Info);
3005
3006  void *InsertPos = nullptr;
3007  if (FunctionNoProtoType *FT =
3008        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
3009    return QualType(FT, 0);
3010
3011  QualType Canonical;
3012  if (!ResultTy.isCanonical()) {
3013    Canonical = getFunctionNoProtoType(getCanonicalType(ResultTy), Info);
3014
3015    // Get the new insert position for the node we care about.
3016    FunctionNoProtoType *NewIP =
3017      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
3018    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
3019  }
3020
3021  FunctionProtoType::ExtInfo newInfo = Info.withCallingConv(CallConv);
3022  FunctionNoProtoType *New = new (*this, TypeAlignment)
3023    FunctionNoProtoType(ResultTy, Canonical, newInfo);
3024  Types.push_back(New);
3025  FunctionNoProtoTypes.InsertNode(New, InsertPos);
3026  return QualType(New, 0);
3027}
3028
3029/// \brief Determine whether \p T is canonical as the result type of a function.
3030static bool isCanonicalResultType(QualType T) {
3031  return T.isCanonical() &&
3032         (T.getObjCLifetime() == Qualifiers::OCL_None ||
3033          T.getObjCLifetime() == Qualifiers::OCL_ExplicitNone);
3034}
3035
3036CanQualType
3037ASTContext::getCanonicalFunctionResultType(QualType ResultType) const {
3038  CanQualType CanResultType = getCanonicalType(ResultType);
3039
3040  // Canonical result types do not have ARC lifetime qualifiers.
3041  if (CanResultType.getQualifiers().hasObjCLifetime()) {
3042    Qualifiers Qs = CanResultType.getQualifiers();
3043    Qs.removeObjCLifetime();
3044    return CanQualType::CreateUnsafe(
3045             getQualifiedType(CanResultType.getUnqualifiedType(), Qs));
3046  }
3047
3048  return CanResultType;
3049}
3050
3051QualType
3052ASTContext::getFunctionType(QualType ResultTy, ArrayRef<QualType> ArgArray,
3053                            const FunctionProtoType::ExtProtoInfo &EPI) const {
3054  size_t NumArgs = ArgArray.size();
3055
3056  // Unique functions, to guarantee there is only one function of a particular
3057  // structure.
3058  llvm::FoldingSetNodeID ID;
3059  FunctionProtoType::Profile(ID, ResultTy, ArgArray.begin(), NumArgs, EPI,
3060                             *this);
3061
3062  void *InsertPos = nullptr;
3063  if (FunctionProtoType *FTP =
3064        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
3065    return QualType(FTP, 0);
3066
3067  // Determine whether the type being created is already canonical or not.
3068  bool isCanonical =
3069    EPI.ExceptionSpec.Type == EST_None && isCanonicalResultType(ResultTy) &&
3070    !EPI.HasTrailingReturn;
3071  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
3072    if (!ArgArray[i].isCanonicalAsParam())
3073      isCanonical = false;
3074
3075  // If this type isn't canonical, get the canonical version of it.
3076  // The exception spec is not part of the canonical type.
3077  QualType Canonical;
3078  if (!isCanonical) {
3079    SmallVector<QualType, 16> CanonicalArgs;
3080    CanonicalArgs.reserve(NumArgs);
3081    for (unsigned i = 0; i != NumArgs; ++i)
3082      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
3083
3084    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
3085    CanonicalEPI.HasTrailingReturn = false;
3086    CanonicalEPI.ExceptionSpec = FunctionProtoType::ExceptionSpecInfo();
3087
3088    // Adjust the canonical function result type.
3089    CanQualType CanResultTy = getCanonicalFunctionResultType(ResultTy);
3090    Canonical = getFunctionType(CanResultTy, CanonicalArgs, CanonicalEPI);
3091
3092    // Get the new insert position for the node we care about.
3093    FunctionProtoType *NewIP =
3094      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
3095    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
3096  }
3097
3098  // FunctionProtoType objects are allocated with extra bytes after
3099  // them for three variable size arrays at the end:
3100  //  - parameter types
3101  //  - exception types
3102  //  - consumed-arguments flags
3103  // Instead of the exception types, there could be a noexcept
3104  // expression, or information used to resolve the exception
3105  // specification.
3106  size_t Size = sizeof(FunctionProtoType) +
3107                NumArgs * sizeof(QualType);
3108  if (EPI.ExceptionSpec.Type == EST_Dynamic) {
3109    Size += EPI.ExceptionSpec.Exceptions.size() * sizeof(QualType);
3110  } else if (EPI.ExceptionSpec.Type == EST_ComputedNoexcept) {
3111    Size += sizeof(Expr*);
3112  } else if (EPI.ExceptionSpec.Type == EST_Uninstantiated) {
3113    Size += 2 * sizeof(FunctionDecl*);
3114  } else if (EPI.ExceptionSpec.Type == EST_Unevaluated) {
3115    Size += sizeof(FunctionDecl*);
3116  }
3117  if (EPI.ConsumedParameters)
3118    Size += NumArgs * sizeof(bool);
3119
3120  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
3121  FunctionProtoType::ExtProtoInfo newEPI = EPI;
3122  new (FTP) FunctionProtoType(ResultTy, ArgArray, Canonical, newEPI);
3123  Types.push_back(FTP);
3124  FunctionProtoTypes.InsertNode(FTP, InsertPos);
3125  return QualType(FTP, 0);
3126}
3127
3128/// Return pipe type for the specified type.
3129QualType ASTContext::getPipeType(QualType T) const {
3130  llvm::FoldingSetNodeID ID;
3131  PipeType::Profile(ID, T);
3132
3133  void *InsertPos = 0;
3134  if (PipeType *PT = PipeTypes.FindNodeOrInsertPos(ID, InsertPos))
3135    return QualType(PT, 0);
3136
3137  // If the pipe element type isn't canonical, this won't be a canonical type
3138  // either, so fill in the canonical type field.
3139  QualType Canonical;
3140  if (!T.isCanonical()) {
3141    Canonical = getPipeType(getCanonicalType(T));
3142
3143    // Get the new insert position for the node we care about.
3144    PipeType *NewIP = PipeTypes.FindNodeOrInsertPos(ID, InsertPos);
3145    assert(!NewIP && "Shouldn't be in the map!");
3146    (void)NewIP;
3147  }
3148  PipeType *New = new (*this, TypeAlignment) PipeType(T, Canonical);
3149  Types.push_back(New);
3150  PipeTypes.InsertNode(New, InsertPos);
3151  return QualType(New, 0);
3152}
3153
3154#ifndef NDEBUG
3155static bool NeedsInjectedClassNameType(const RecordDecl *D) {
3156  if (!isa<CXXRecordDecl>(D)) return false;
3157  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
3158  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
3159    return true;
3160  if (RD->getDescribedClassTemplate() &&
3161      !isa<ClassTemplateSpecializationDecl>(RD))
3162    return true;
3163  return false;
3164}
3165#endif
3166
3167/// getInjectedClassNameType - Return the unique reference to the
3168/// injected class name type for the specified templated declaration.
3169QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
3170                                              QualType TST) const {
3171  assert(NeedsInjectedClassNameType(Decl));
3172  if (Decl->TypeForDecl) {
3173    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
3174  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDecl()) {
3175    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
3176    Decl->TypeForDecl = PrevDecl->TypeForDecl;
3177    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
3178  } else {
3179    Type *newType =
3180      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
3181    Decl->TypeForDecl = newType;
3182    Types.push_back(newType);
3183  }
3184  return QualType(Decl->TypeForDecl, 0);
3185}
3186
3187/// getTypeDeclType - Return the unique reference to the type for the
3188/// specified type declaration.
3189QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) const {
3190  assert(Decl && "Passed null for Decl param");
3191  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
3192
3193  if (const TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Decl))
3194    return getTypedefType(Typedef);
3195
3196  assert(!isa<TemplateTypeParmDecl>(Decl) &&
3197         "Template type parameter types are always available.");
3198
3199  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
3200    assert(Record->isFirstDecl() && "struct/union has previous declaration");
3201    assert(!NeedsInjectedClassNameType(Record));
3202    return getRecordType(Record);
3203  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
3204    assert(Enum->isFirstDecl() && "enum has previous declaration");
3205    return getEnumType(Enum);
3206  } else if (const UnresolvedUsingTypenameDecl *Using =
3207               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
3208    Type *newType = new (*this, TypeAlignment) UnresolvedUsingType(Using);
3209    Decl->TypeForDecl = newType;
3210    Types.push_back(newType);
3211  } else
3212    llvm_unreachable("TypeDecl without a type?");
3213
3214  return QualType(Decl->TypeForDecl, 0);
3215}
3216
3217/// getTypedefType - Return the unique reference to the type for the
3218/// specified typedef name decl.
3219QualType
3220ASTContext::getTypedefType(const TypedefNameDecl *Decl,
3221                           QualType Canonical) const {
3222  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
3223
3224  if (Canonical.isNull())
3225    Canonical = getCanonicalType(Decl->getUnderlyingType());
3226  TypedefType *newType = new(*this, TypeAlignment)
3227    TypedefType(Type::Typedef, Decl, Canonical);
3228  Decl->TypeForDecl = newType;
3229  Types.push_back(newType);
3230  return QualType(newType, 0);
3231}
3232
3233QualType ASTContext::getRecordType(const RecordDecl *Decl) const {
3234  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
3235
3236  if (const RecordDecl *PrevDecl = Decl->getPreviousDecl())
3237    if (PrevDecl->TypeForDecl)
3238      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
3239
3240  RecordType *newType = new (*this, TypeAlignment) RecordType(Decl);
3241  Decl->TypeForDecl = newType;
3242  Types.push_back(newType);
3243  return QualType(newType, 0);
3244}
3245
3246QualType ASTContext::getEnumType(const EnumDecl *Decl) const {
3247  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
3248
3249  if (const EnumDecl *PrevDecl = Decl->getPreviousDecl())
3250    if (PrevDecl->TypeForDecl)
3251      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
3252
3253  EnumType *newType = new (*this, TypeAlignment) EnumType(Decl);
3254  Decl->TypeForDecl = newType;
3255  Types.push_back(newType);
3256  return QualType(newType, 0);
3257}
3258
3259QualType ASTContext::getAttributedType(AttributedType::Kind attrKind,
3260                                       QualType modifiedType,
3261                                       QualType equivalentType) {
3262  llvm::FoldingSetNodeID id;
3263  AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
3264
3265  void *insertPos = nullptr;
3266  AttributedType *type = AttributedTypes.FindNodeOrInsertPos(id, insertPos);
3267  if (type) return QualType(type, 0);
3268
3269  QualType canon = getCanonicalType(equivalentType);
3270  type = new (*this, TypeAlignment)
3271           AttributedType(canon, attrKind, modifiedType, equivalentType);
3272
3273  Types.push_back(type);
3274  AttributedTypes.InsertNode(type, insertPos);
3275
3276  return QualType(type, 0);
3277}
3278
3279/// \brief Retrieve a substitution-result type.
3280QualType
3281ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
3282                                         QualType Replacement) const {
3283  assert(Replacement.isCanonical()
3284         && "replacement types must always be canonical");
3285
3286  llvm::FoldingSetNodeID ID;
3287  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
3288  void *InsertPos = nullptr;
3289  SubstTemplateTypeParmType *SubstParm
3290    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
3291
3292  if (!SubstParm) {
3293    SubstParm = new (*this, TypeAlignment)
3294      SubstTemplateTypeParmType(Parm, Replacement);
3295    Types.push_back(SubstParm);
3296    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
3297  }
3298
3299  return QualType(SubstParm, 0);
3300}
3301
3302/// \brief Retrieve a
3303QualType ASTContext::getSubstTemplateTypeParmPackType(
3304                                          const TemplateTypeParmType *Parm,
3305                                              const TemplateArgument &ArgPack) {
3306#ifndef NDEBUG
3307  for (const auto &P : ArgPack.pack_elements()) {
3308    assert(P.getKind() == TemplateArgument::Type &&"Pack contains a non-type");
3309    assert(P.getAsType().isCanonical() && "Pack contains non-canonical type");
3310  }
3311#endif
3312
3313  llvm::FoldingSetNodeID ID;
3314  SubstTemplateTypeParmPackType::Profile(ID, Parm, ArgPack);
3315  void *InsertPos = nullptr;
3316  if (SubstTemplateTypeParmPackType *SubstParm
3317        = SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos))
3318    return QualType(SubstParm, 0);
3319
3320  QualType Canon;
3321  if (!Parm->isCanonicalUnqualified()) {
3322    Canon = getCanonicalType(QualType(Parm, 0));
3323    Canon = getSubstTemplateTypeParmPackType(cast<TemplateTypeParmType>(Canon),
3324                                             ArgPack);
3325    SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos);
3326  }
3327
3328  SubstTemplateTypeParmPackType *SubstParm
3329    = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
3330                                                               ArgPack);
3331  Types.push_back(SubstParm);
3332  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
3333  return QualType(SubstParm, 0);
3334}
3335
3336/// \brief Retrieve the template type parameter type for a template
3337/// parameter or parameter pack with the given depth, index, and (optionally)
3338/// name.
3339QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
3340                                             bool ParameterPack,
3341                                             TemplateTypeParmDecl *TTPDecl) const {
3342  llvm::FoldingSetNodeID ID;
3343  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, TTPDecl);
3344  void *InsertPos = nullptr;
3345  TemplateTypeParmType *TypeParm
3346    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
3347
3348  if (TypeParm)
3349    return QualType(TypeParm, 0);
3350
3351  if (TTPDecl) {
3352    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
3353    TypeParm = new (*this, TypeAlignment) TemplateTypeParmType(TTPDecl, Canon);
3354
3355    TemplateTypeParmType *TypeCheck
3356      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
3357    assert(!TypeCheck && "Template type parameter canonical type broken");
3358    (void)TypeCheck;
3359  } else
3360    TypeParm = new (*this, TypeAlignment)
3361      TemplateTypeParmType(Depth, Index, ParameterPack);
3362
3363  Types.push_back(TypeParm);
3364  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
3365
3366  return QualType(TypeParm, 0);
3367}
3368
3369TypeSourceInfo *
3370ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
3371                                              SourceLocation NameLoc,
3372                                        const TemplateArgumentListInfo &Args,
3373                                              QualType Underlying) const {
3374  assert(!Name.getAsDependentTemplateName() &&
3375         "No dependent template names here!");
3376  QualType TST = getTemplateSpecializationType(Name, Args, Underlying);
3377
3378  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
3379  TemplateSpecializationTypeLoc TL =
3380      DI->getTypeLoc().castAs<TemplateSpecializationTypeLoc>();
3381  TL.setTemplateKeywordLoc(SourceLocation());
3382  TL.setTemplateNameLoc(NameLoc);
3383  TL.setLAngleLoc(Args.getLAngleLoc());
3384  TL.setRAngleLoc(Args.getRAngleLoc());
3385  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
3386    TL.setArgLocInfo(i, Args[i].getLocInfo());
3387  return DI;
3388}
3389
3390QualType
3391ASTContext::getTemplateSpecializationType(TemplateName Template,
3392                                          const TemplateArgumentListInfo &Args,
3393                                          QualType Underlying) const {
3394  assert(!Template.getAsDependentTemplateName() &&
3395         "No dependent template names here!");
3396
3397  unsigned NumArgs = Args.size();
3398
3399  SmallVector<TemplateArgument, 4> ArgVec;
3400  ArgVec.reserve(NumArgs);
3401  for (unsigned i = 0; i != NumArgs; ++i)
3402    ArgVec.push_back(Args[i].getArgument());
3403
3404  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
3405                                       Underlying);
3406}
3407
3408#ifndef NDEBUG
3409static bool hasAnyPackExpansions(const TemplateArgument *Args,
3410                                 unsigned NumArgs) {
3411  for (unsigned I = 0; I != NumArgs; ++I)
3412    if (Args[I].isPackExpansion())
3413      return true;
3414
3415  return true;
3416}
3417#endif
3418
3419QualType
3420ASTContext::getTemplateSpecializationType(TemplateName Template,
3421                                          const TemplateArgument *Args,
3422                                          unsigned NumArgs,
3423                                          QualType Underlying) const {
3424  assert(!Template.getAsDependentTemplateName() &&
3425         "No dependent template names here!");
3426  // Look through qualified template names.
3427  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
3428    Template = TemplateName(QTN->getTemplateDecl());
3429
3430  bool IsTypeAlias =
3431    Template.getAsTemplateDecl() &&
3432    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
3433  QualType CanonType;
3434  if (!Underlying.isNull())
3435    CanonType = getCanonicalType(Underlying);
3436  else {
3437    // We can get here with an alias template when the specialization contains
3438    // a pack expansion that does not match up with a parameter pack.
3439    assert((!IsTypeAlias || hasAnyPackExpansions(Args, NumArgs)) &&
3440           "Caller must compute aliased type");
3441    IsTypeAlias = false;
3442    CanonType = getCanonicalTemplateSpecializationType(Template, Args,
3443                                                       NumArgs);
3444  }
3445
3446  // Allocate the (non-canonical) template specialization type, but don't
3447  // try to unique it: these types typically have location information that
3448  // we don't unique and don't want to lose.
3449  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
3450                       sizeof(TemplateArgument) * NumArgs +
3451                       (IsTypeAlias? sizeof(QualType) : 0),
3452                       TypeAlignment);
3453  TemplateSpecializationType *Spec
3454    = new (Mem) TemplateSpecializationType(Template, Args, NumArgs, CanonType,
3455                                         IsTypeAlias ? Underlying : QualType());
3456
3457  Types.push_back(Spec);
3458  return QualType(Spec, 0);
3459}
3460
3461QualType
3462ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
3463                                                   const TemplateArgument *Args,
3464                                                   unsigned NumArgs) const {
3465  assert(!Template.getAsDependentTemplateName() &&
3466         "No dependent template names here!");
3467
3468  // Look through qualified template names.
3469  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
3470    Template = TemplateName(QTN->getTemplateDecl());
3471
3472  // Build the canonical template specialization type.
3473  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
3474  SmallVector<TemplateArgument, 4> CanonArgs;
3475  CanonArgs.reserve(NumArgs);
3476  for (unsigned I = 0; I != NumArgs; ++I)
3477    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
3478
3479  // Determine whether this canonical template specialization type already
3480  // exists.
3481  llvm::FoldingSetNodeID ID;
3482  TemplateSpecializationType::Profile(ID, CanonTemplate,
3483                                      CanonArgs.data(), NumArgs, *this);
3484
3485  void *InsertPos = nullptr;
3486  TemplateSpecializationType *Spec
3487    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3488
3489  if (!Spec) {
3490    // Allocate a new canonical template specialization type.
3491    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
3492                          sizeof(TemplateArgument) * NumArgs),
3493                         TypeAlignment);
3494    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
3495                                                CanonArgs.data(), NumArgs,
3496                                                QualType(), QualType());
3497    Types.push_back(Spec);
3498    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
3499  }
3500
3501  assert(Spec->isDependentType() &&
3502         "Non-dependent template-id type must have a canonical type");
3503  return QualType(Spec, 0);
3504}
3505
3506QualType
3507ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
3508                              NestedNameSpecifier *NNS,
3509                              QualType NamedType) const {
3510  llvm::FoldingSetNodeID ID;
3511  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
3512
3513  void *InsertPos = nullptr;
3514  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
3515  if (T)
3516    return QualType(T, 0);
3517
3518  QualType Canon = NamedType;
3519  if (!Canon.isCanonical()) {
3520    Canon = getCanonicalType(NamedType);
3521    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
3522    assert(!CheckT && "Elaborated canonical type broken");
3523    (void)CheckT;
3524  }
3525
3526  T = new (*this, TypeAlignment) ElaboratedType(Keyword, NNS, NamedType, Canon);
3527  Types.push_back(T);
3528  ElaboratedTypes.InsertNode(T, InsertPos);
3529  return QualType(T, 0);
3530}
3531
3532QualType
3533ASTContext::getParenType(QualType InnerType) const {
3534  llvm::FoldingSetNodeID ID;
3535  ParenType::Profile(ID, InnerType);
3536
3537  void *InsertPos = nullptr;
3538  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
3539  if (T)
3540    return QualType(T, 0);
3541
3542  QualType Canon = InnerType;
3543  if (!Canon.isCanonical()) {
3544    Canon = getCanonicalType(InnerType);
3545    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
3546    assert(!CheckT && "Paren canonical type broken");
3547    (void)CheckT;
3548  }
3549
3550  T = new (*this, TypeAlignment) ParenType(InnerType, Canon);
3551  Types.push_back(T);
3552  ParenTypes.InsertNode(T, InsertPos);
3553  return QualType(T, 0);
3554}
3555
3556QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
3557                                          NestedNameSpecifier *NNS,
3558                                          const IdentifierInfo *Name,
3559                                          QualType Canon) const {
3560  if (Canon.isNull()) {
3561    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
3562    ElaboratedTypeKeyword CanonKeyword = Keyword;
3563    if (Keyword == ETK_None)
3564      CanonKeyword = ETK_Typename;
3565
3566    if (CanonNNS != NNS || CanonKeyword != Keyword)
3567      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
3568  }
3569
3570  llvm::FoldingSetNodeID ID;
3571  DependentNameType::Profile(ID, Keyword, NNS, Name);
3572
3573  void *InsertPos = nullptr;
3574  DependentNameType *T
3575    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
3576  if (T)
3577    return QualType(T, 0);
3578
3579  T = new (*this, TypeAlignment) DependentNameType(Keyword, NNS, Name, Canon);
3580  Types.push_back(T);
3581  DependentNameTypes.InsertNode(T, InsertPos);
3582  return QualType(T, 0);
3583}
3584
3585QualType
3586ASTContext::getDependentTemplateSpecializationType(
3587                                 ElaboratedTypeKeyword Keyword,
3588                                 NestedNameSpecifier *NNS,
3589                                 const IdentifierInfo *Name,
3590                                 const TemplateArgumentListInfo &Args) const {
3591  // TODO: avoid this copy
3592  SmallVector<TemplateArgument, 16> ArgCopy;
3593  for (unsigned I = 0, E = Args.size(); I != E; ++I)
3594    ArgCopy.push_back(Args[I].getArgument());
3595  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
3596                                                ArgCopy.size(),
3597                                                ArgCopy.data());
3598}
3599
3600QualType
3601ASTContext::getDependentTemplateSpecializationType(
3602                                 ElaboratedTypeKeyword Keyword,
3603                                 NestedNameSpecifier *NNS,
3604                                 const IdentifierInfo *Name,
3605                                 unsigned NumArgs,
3606                                 const TemplateArgument *Args) const {
3607  assert((!NNS || NNS->isDependent()) &&
3608         "nested-name-specifier must be dependent");
3609
3610  llvm::FoldingSetNodeID ID;
3611  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
3612                                               Name, NumArgs, Args);
3613
3614  void *InsertPos = nullptr;
3615  DependentTemplateSpecializationType *T
3616    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3617  if (T)
3618    return QualType(T, 0);
3619
3620  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
3621
3622  ElaboratedTypeKeyword CanonKeyword = Keyword;
3623  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
3624
3625  bool AnyNonCanonArgs = false;
3626  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
3627  for (unsigned I = 0; I != NumArgs; ++I) {
3628    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
3629    if (!CanonArgs[I].structurallyEquals(Args[I]))
3630      AnyNonCanonArgs = true;
3631  }
3632
3633  QualType Canon;
3634  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
3635    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
3636                                                   Name, NumArgs,
3637                                                   CanonArgs.data());
3638
3639    // Find the insert position again.
3640    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3641  }
3642
3643  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
3644                        sizeof(TemplateArgument) * NumArgs),
3645                       TypeAlignment);
3646  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
3647                                                    Name, NumArgs, Args, Canon);
3648  Types.push_back(T);
3649  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
3650  return QualType(T, 0);
3651}
3652
3653QualType ASTContext::getPackExpansionType(QualType Pattern,
3654                                          Optional<unsigned> NumExpansions) {
3655  llvm::FoldingSetNodeID ID;
3656  PackExpansionType::Profile(ID, Pattern, NumExpansions);
3657
3658  assert(Pattern->containsUnexpandedParameterPack() &&
3659         "Pack expansions must expand one or more parameter packs");
3660  void *InsertPos = nullptr;
3661  PackExpansionType *T
3662    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3663  if (T)
3664    return QualType(T, 0);
3665
3666  QualType Canon;
3667  if (!Pattern.isCanonical()) {
3668    Canon = getCanonicalType(Pattern);
3669    // The canonical type might not contain an unexpanded parameter pack, if it
3670    // contains an alias template specialization which ignores one of its
3671    // parameters.
3672    if (Canon->containsUnexpandedParameterPack()) {
3673      Canon = getPackExpansionType(Canon, NumExpansions);
3674
3675      // Find the insert position again, in case we inserted an element into
3676      // PackExpansionTypes and invalidated our insert position.
3677      PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3678    }
3679  }
3680
3681  T = new (*this, TypeAlignment)
3682      PackExpansionType(Pattern, Canon, NumExpansions);
3683  Types.push_back(T);
3684  PackExpansionTypes.InsertNode(T, InsertPos);
3685  return QualType(T, 0);
3686}
3687
3688/// CmpProtocolNames - Comparison predicate for sorting protocols
3689/// alphabetically.
3690static int CmpProtocolNames(ObjCProtocolDecl *const *LHS,
3691                            ObjCProtocolDecl *const *RHS) {
3692  return DeclarationName::compare((*LHS)->getDeclName(), (*RHS)->getDeclName());
3693}
3694
3695static bool areSortedAndUniqued(ArrayRef<ObjCProtocolDecl *> Protocols) {
3696  if (Protocols.empty()) return true;
3697
3698  if (Protocols[0]->getCanonicalDecl() != Protocols[0])
3699    return false;
3700
3701  for (unsigned i = 1; i != Protocols.size(); ++i)
3702    if (CmpProtocolNames(&Protocols[i - 1], &Protocols[i]) >= 0 ||
3703        Protocols[i]->getCanonicalDecl() != Protocols[i])
3704      return false;
3705  return true;
3706}
3707
3708static void
3709SortAndUniqueProtocols(SmallVectorImpl<ObjCProtocolDecl *> &Protocols) {
3710  // Sort protocols, keyed by name.
3711  llvm::array_pod_sort(Protocols.begin(), Protocols.end(), CmpProtocolNames);
3712
3713  // Canonicalize.
3714  for (ObjCProtocolDecl *&P : Protocols)
3715    P = P->getCanonicalDecl();
3716
3717  // Remove duplicates.
3718  auto ProtocolsEnd = std::unique(Protocols.begin(), Protocols.end());
3719  Protocols.erase(ProtocolsEnd, Protocols.end());
3720}
3721
3722QualType ASTContext::getObjCObjectType(QualType BaseType,
3723                                       ObjCProtocolDecl * const *Protocols,
3724                                       unsigned NumProtocols) const {
3725  return getObjCObjectType(BaseType, { },
3726                           llvm::makeArrayRef(Protocols, NumProtocols),
3727                           /*isKindOf=*/false);
3728}
3729
3730QualType ASTContext::getObjCObjectType(
3731           QualType baseType,
3732           ArrayRef<QualType> typeArgs,
3733           ArrayRef<ObjCProtocolDecl *> protocols,
3734           bool isKindOf) const {
3735  // If the base type is an interface and there aren't any protocols or
3736  // type arguments to add, then the interface type will do just fine.
3737  if (typeArgs.empty() && protocols.empty() && !isKindOf &&
3738      isa<ObjCInterfaceType>(baseType))
3739    return baseType;
3740
3741  // Look in the folding set for an existing type.
3742  llvm::FoldingSetNodeID ID;
3743  ObjCObjectTypeImpl::Profile(ID, baseType, typeArgs, protocols, isKindOf);
3744  void *InsertPos = nullptr;
3745  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
3746    return QualType(QT, 0);
3747
3748  // Determine the type arguments to be used for canonicalization,
3749  // which may be explicitly specified here or written on the base
3750  // type.
3751  ArrayRef<QualType> effectiveTypeArgs = typeArgs;
3752  if (effectiveTypeArgs.empty()) {
3753    if (auto baseObject = baseType->getAs<ObjCObjectType>())
3754      effectiveTypeArgs = baseObject->getTypeArgs();
3755  }
3756
3757  // Build the canonical type, which has the canonical base type and a
3758  // sorted-and-uniqued list of protocols and the type arguments
3759  // canonicalized.
3760  QualType canonical;
3761  bool typeArgsAreCanonical = std::all_of(effectiveTypeArgs.begin(),
3762                                          effectiveTypeArgs.end(),
3763                                          [&](QualType type) {
3764                                            return type.isCanonical();
3765                                          });
3766  bool protocolsSorted = areSortedAndUniqued(protocols);
3767  if (!typeArgsAreCanonical || !protocolsSorted || !baseType.isCanonical()) {
3768    // Determine the canonical type arguments.
3769    ArrayRef<QualType> canonTypeArgs;
3770    SmallVector<QualType, 4> canonTypeArgsVec;
3771    if (!typeArgsAreCanonical) {
3772      canonTypeArgsVec.reserve(effectiveTypeArgs.size());
3773      for (auto typeArg : effectiveTypeArgs)
3774        canonTypeArgsVec.push_back(getCanonicalType(typeArg));
3775      canonTypeArgs = canonTypeArgsVec;
3776    } else {
3777      canonTypeArgs = effectiveTypeArgs;
3778    }
3779
3780    ArrayRef<ObjCProtocolDecl *> canonProtocols;
3781    SmallVector<ObjCProtocolDecl*, 8> canonProtocolsVec;
3782    if (!protocolsSorted) {
3783      canonProtocolsVec.append(protocols.begin(), protocols.end());
3784      SortAndUniqueProtocols(canonProtocolsVec);
3785      canonProtocols = canonProtocolsVec;
3786    } else {
3787      canonProtocols = protocols;
3788    }
3789
3790    canonical = getObjCObjectType(getCanonicalType(baseType), canonTypeArgs,
3791                                  canonProtocols, isKindOf);
3792
3793    // Regenerate InsertPos.
3794    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
3795  }
3796
3797  unsigned size = sizeof(ObjCObjectTypeImpl);
3798  size += typeArgs.size() * sizeof(QualType);
3799  size += protocols.size() * sizeof(ObjCProtocolDecl *);
3800  void *mem = Allocate(size, TypeAlignment);
3801  ObjCObjectTypeImpl *T =
3802    new (mem) ObjCObjectTypeImpl(canonical, baseType, typeArgs, protocols,
3803                                 isKindOf);
3804
3805  Types.push_back(T);
3806  ObjCObjectTypes.InsertNode(T, InsertPos);
3807  return QualType(T, 0);
3808}
3809
3810/// ObjCObjectAdoptsQTypeProtocols - Checks that protocols in IC's
3811/// protocol list adopt all protocols in QT's qualified-id protocol
3812/// list.
3813bool ASTContext::ObjCObjectAdoptsQTypeProtocols(QualType QT,
3814                                                ObjCInterfaceDecl *IC) {
3815  if (!QT->isObjCQualifiedIdType())
3816    return false;
3817
3818  if (const ObjCObjectPointerType *OPT = QT->getAs<ObjCObjectPointerType>()) {
3819    // If both the right and left sides have qualifiers.
3820    for (auto *Proto : OPT->quals()) {
3821      if (!IC->ClassImplementsProtocol(Proto, false))
3822        return false;
3823    }
3824    return true;
3825  }
3826  return false;
3827}
3828
3829/// QIdProtocolsAdoptObjCObjectProtocols - Checks that protocols in
3830/// QT's qualified-id protocol list adopt all protocols in IDecl's list
3831/// of protocols.
3832bool ASTContext::QIdProtocolsAdoptObjCObjectProtocols(QualType QT,
3833                                                ObjCInterfaceDecl *IDecl) {
3834  if (!QT->isObjCQualifiedIdType())
3835    return false;
3836  const ObjCObjectPointerType *OPT = QT->getAs<ObjCObjectPointerType>();
3837  if (!OPT)
3838    return false;
3839  if (!IDecl->hasDefinition())
3840    return false;
3841  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocols;
3842  CollectInheritedProtocols(IDecl, InheritedProtocols);
3843  if (InheritedProtocols.empty())
3844    return false;
3845  // Check that if every protocol in list of id<plist> conforms to a protcol
3846  // of IDecl's, then bridge casting is ok.
3847  bool Conforms = false;
3848  for (auto *Proto : OPT->quals()) {
3849    Conforms = false;
3850    for (auto *PI : InheritedProtocols) {
3851      if (ProtocolCompatibleWithProtocol(Proto, PI)) {
3852        Conforms = true;
3853        break;
3854      }
3855    }
3856    if (!Conforms)
3857      break;
3858  }
3859  if (Conforms)
3860    return true;
3861
3862  for (auto *PI : InheritedProtocols) {
3863    // If both the right and left sides have qualifiers.
3864    bool Adopts = false;
3865    for (auto *Proto : OPT->quals()) {
3866      // return 'true' if 'PI' is in the inheritance hierarchy of Proto
3867      if ((Adopts = ProtocolCompatibleWithProtocol(PI, Proto)))
3868        break;
3869    }
3870    if (!Adopts)
3871      return false;
3872  }
3873  return true;
3874}
3875
3876/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
3877/// the given object type.
3878QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
3879  llvm::FoldingSetNodeID ID;
3880  ObjCObjectPointerType::Profile(ID, ObjectT);
3881
3882  void *InsertPos = nullptr;
3883  if (ObjCObjectPointerType *QT =
3884              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
3885    return QualType(QT, 0);
3886
3887  // Find the canonical object type.
3888  QualType Canonical;
3889  if (!ObjectT.isCanonical()) {
3890    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
3891
3892    // Regenerate InsertPos.
3893    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
3894  }
3895
3896  // No match.
3897  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
3898  ObjCObjectPointerType *QType =
3899    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
3900
3901  Types.push_back(QType);
3902  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
3903  return QualType(QType, 0);
3904}
3905
3906/// getObjCInterfaceType - Return the unique reference to the type for the
3907/// specified ObjC interface decl. The list of protocols is optional.
3908QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
3909                                          ObjCInterfaceDecl *PrevDecl) const {
3910  if (Decl->TypeForDecl)
3911    return QualType(Decl->TypeForDecl, 0);
3912
3913  if (PrevDecl) {
3914    assert(PrevDecl->TypeForDecl && "previous decl has no TypeForDecl");
3915    Decl->TypeForDecl = PrevDecl->TypeForDecl;
3916    return QualType(PrevDecl->TypeForDecl, 0);
3917  }
3918
3919  // Prefer the definition, if there is one.
3920  if (const ObjCInterfaceDecl *Def = Decl->getDefinition())
3921    Decl = Def;
3922
3923  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
3924  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
3925  Decl->TypeForDecl = T;
3926  Types.push_back(T);
3927  return QualType(T, 0);
3928}
3929
3930/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
3931/// TypeOfExprType AST's (since expression's are never shared). For example,
3932/// multiple declarations that refer to "typeof(x)" all contain different
3933/// DeclRefExpr's. This doesn't effect the type checker, since it operates
3934/// on canonical type's (which are always unique).
3935QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
3936  TypeOfExprType *toe;
3937  if (tofExpr->isTypeDependent()) {
3938    llvm::FoldingSetNodeID ID;
3939    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
3940
3941    void *InsertPos = nullptr;
3942    DependentTypeOfExprType *Canon
3943      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
3944    if (Canon) {
3945      // We already have a "canonical" version of an identical, dependent
3946      // typeof(expr) type. Use that as our canonical type.
3947      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
3948                                          QualType((TypeOfExprType*)Canon, 0));
3949    } else {
3950      // Build a new, canonical typeof(expr) type.
3951      Canon
3952        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
3953      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
3954      toe = Canon;
3955    }
3956  } else {
3957    QualType Canonical = getCanonicalType(tofExpr->getType());
3958    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
3959  }
3960  Types.push_back(toe);
3961  return QualType(toe, 0);
3962}
3963
3964/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
3965/// TypeOfType nodes. The only motivation to unique these nodes would be
3966/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
3967/// an issue. This doesn't affect the type checker, since it operates
3968/// on canonical types (which are always unique).
3969QualType ASTContext::getTypeOfType(QualType tofType) const {
3970  QualType Canonical = getCanonicalType(tofType);
3971  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
3972  Types.push_back(tot);
3973  return QualType(tot, 0);
3974}
3975
3976/// \brief Unlike many "get<Type>" functions, we don't unique DecltypeType
3977/// nodes. This would never be helpful, since each such type has its own
3978/// expression, and would not give a significant memory saving, since there
3979/// is an Expr tree under each such type.
3980QualType ASTContext::getDecltypeType(Expr *e, QualType UnderlyingType) const {
3981  DecltypeType *dt;
3982
3983  // C++11 [temp.type]p2:
3984  //   If an expression e involves a template parameter, decltype(e) denotes a
3985  //   unique dependent type. Two such decltype-specifiers refer to the same
3986  //   type only if their expressions are equivalent (14.5.6.1).
3987  if (e->isInstantiationDependent()) {
3988    llvm::FoldingSetNodeID ID;
3989    DependentDecltypeType::Profile(ID, *this, e);
3990
3991    void *InsertPos = nullptr;
3992    DependentDecltypeType *Canon
3993      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
3994    if (!Canon) {
3995      // Build a new, canonical typeof(expr) type.
3996      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
3997      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
3998    }
3999    dt = new (*this, TypeAlignment)
4000        DecltypeType(e, UnderlyingType, QualType((DecltypeType *)Canon, 0));
4001  } else {
4002    dt = new (*this, TypeAlignment)
4003        DecltypeType(e, UnderlyingType, getCanonicalType(UnderlyingType));
4004  }
4005  Types.push_back(dt);
4006  return QualType(dt, 0);
4007}
4008
4009/// getUnaryTransformationType - We don't unique these, since the memory
4010/// savings are minimal and these are rare.
4011QualType ASTContext::getUnaryTransformType(QualType BaseType,
4012                                           QualType UnderlyingType,
4013                                           UnaryTransformType::UTTKind Kind)
4014    const {
4015  UnaryTransformType *Ty =
4016    new (*this, TypeAlignment) UnaryTransformType (BaseType, UnderlyingType,
4017                                                   Kind,
4018                                 UnderlyingType->isDependentType() ?
4019                                 QualType() : getCanonicalType(UnderlyingType));
4020  Types.push_back(Ty);
4021  return QualType(Ty, 0);
4022}
4023
4024/// getAutoType - Return the uniqued reference to the 'auto' type which has been
4025/// deduced to the given type, or to the canonical undeduced 'auto' type, or the
4026/// canonical deduced-but-dependent 'auto' type.
4027QualType ASTContext::getAutoType(QualType DeducedType, AutoTypeKeyword Keyword,
4028                                 bool IsDependent) const {
4029  if (DeducedType.isNull() && Keyword == AutoTypeKeyword::Auto && !IsDependent)
4030    return getAutoDeductType();
4031
4032  // Look in the folding set for an existing type.
4033  void *InsertPos = nullptr;
4034  llvm::FoldingSetNodeID ID;
4035  AutoType::Profile(ID, DeducedType, Keyword, IsDependent);
4036  if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
4037    return QualType(AT, 0);
4038
4039  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType,
4040                                                     Keyword,
4041                                                     IsDependent);
4042  Types.push_back(AT);
4043  if (InsertPos)
4044    AutoTypes.InsertNode(AT, InsertPos);
4045  return QualType(AT, 0);
4046}
4047
4048/// getAtomicType - Return the uniqued reference to the atomic type for
4049/// the given value type.
4050QualType ASTContext::getAtomicType(QualType T) const {
4051  // Unique pointers, to guarantee there is only one pointer of a particular
4052  // structure.
4053  llvm::FoldingSetNodeID ID;
4054  AtomicType::Profile(ID, T);
4055
4056  void *InsertPos = nullptr;
4057  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
4058    return QualType(AT, 0);
4059
4060  // If the atomic value type isn't canonical, this won't be a canonical type
4061  // either, so fill in the canonical type field.
4062  QualType Canonical;
4063  if (!T.isCanonical()) {
4064    Canonical = getAtomicType(getCanonicalType(T));
4065
4066    // Get the new insert position for the node we care about.
4067    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
4068    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
4069  }
4070  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
4071  Types.push_back(New);
4072  AtomicTypes.InsertNode(New, InsertPos);
4073  return QualType(New, 0);
4074}
4075
4076/// getAutoDeductType - Get type pattern for deducing against 'auto'.
4077QualType ASTContext::getAutoDeductType() const {
4078  if (AutoDeductTy.isNull())
4079    AutoDeductTy = QualType(
4080      new (*this, TypeAlignment) AutoType(QualType(), AutoTypeKeyword::Auto,
4081                                          /*dependent*/false),
4082      0);
4083  return AutoDeductTy;
4084}
4085
4086/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
4087QualType ASTContext::getAutoRRefDeductType() const {
4088  if (AutoRRefDeductTy.isNull())
4089    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
4090  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
4091  return AutoRRefDeductTy;
4092}
4093
4094/// getTagDeclType - Return the unique reference to the type for the
4095/// specified TagDecl (struct/union/class/enum) decl.
4096QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
4097  assert (Decl);
4098  // FIXME: What is the design on getTagDeclType when it requires casting
4099  // away const?  mutable?
4100  return getTypeDeclType(const_cast<TagDecl*>(Decl));
4101}
4102
4103/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
4104/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
4105/// needs to agree with the definition in <stddef.h>.
4106CanQualType ASTContext::getSizeType() const {
4107  return getFromTargetType(Target->getSizeType());
4108}
4109
4110/// getIntMaxType - Return the unique type for "intmax_t" (C99 7.18.1.5).
4111CanQualType ASTContext::getIntMaxType() const {
4112  return getFromTargetType(Target->getIntMaxType());
4113}
4114
4115/// getUIntMaxType - Return the unique type for "uintmax_t" (C99 7.18.1.5).
4116CanQualType ASTContext::getUIntMaxType() const {
4117  return getFromTargetType(Target->getUIntMaxType());
4118}
4119
4120/// getSignedWCharType - Return the type of "signed wchar_t".
4121/// Used when in C++, as a GCC extension.
4122QualType ASTContext::getSignedWCharType() const {
4123  // FIXME: derive from "Target" ?
4124  return WCharTy;
4125}
4126
4127/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
4128/// Used when in C++, as a GCC extension.
4129QualType ASTContext::getUnsignedWCharType() const {
4130  // FIXME: derive from "Target" ?
4131  return UnsignedIntTy;
4132}
4133
4134QualType ASTContext::getIntPtrType() const {
4135  return getFromTargetType(Target->getIntPtrType());
4136}
4137
4138QualType ASTContext::getUIntPtrType() const {
4139  return getCorrespondingUnsignedType(getIntPtrType());
4140}
4141
4142/// getPointerDiffType - Return the unique type for "ptrdiff_t" (C99 7.17)
4143/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
4144QualType ASTContext::getPointerDiffType() const {
4145  return getFromTargetType(Target->getPtrDiffType(0));
4146}
4147
4148/// \brief Return the unique type for "pid_t" defined in
4149/// <sys/types.h>. We need this to compute the correct type for vfork().
4150QualType ASTContext::getProcessIDType() const {
4151  return getFromTargetType(Target->getProcessIDType());
4152}
4153
4154//===----------------------------------------------------------------------===//
4155//                              Type Operators
4156//===----------------------------------------------------------------------===//
4157
4158CanQualType ASTContext::getCanonicalParamType(QualType T) const {
4159  // Push qualifiers into arrays, and then discard any remaining
4160  // qualifiers.
4161  T = getCanonicalType(T);
4162  T = getVariableArrayDecayedType(T);
4163  const Type *Ty = T.getTypePtr();
4164  QualType Result;
4165  if (isa<ArrayType>(Ty)) {
4166    Result = getArrayDecayedType(QualType(Ty,0));
4167  } else if (isa<FunctionType>(Ty)) {
4168    Result = getPointerType(QualType(Ty, 0));
4169  } else {
4170    Result = QualType(Ty, 0);
4171  }
4172
4173  return CanQualType::CreateUnsafe(Result);
4174}
4175
4176QualType ASTContext::getUnqualifiedArrayType(QualType type,
4177                                             Qualifiers &quals) {
4178  SplitQualType splitType = type.getSplitUnqualifiedType();
4179
4180  // FIXME: getSplitUnqualifiedType() actually walks all the way to
4181  // the unqualified desugared type and then drops it on the floor.
4182  // We then have to strip that sugar back off with
4183  // getUnqualifiedDesugaredType(), which is silly.
4184  const ArrayType *AT =
4185    dyn_cast<ArrayType>(splitType.Ty->getUnqualifiedDesugaredType());
4186
4187  // If we don't have an array, just use the results in splitType.
4188  if (!AT) {
4189    quals = splitType.Quals;
4190    return QualType(splitType.Ty, 0);
4191  }
4192
4193  // Otherwise, recurse on the array's element type.
4194  QualType elementType = AT->getElementType();
4195  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
4196
4197  // If that didn't change the element type, AT has no qualifiers, so we
4198  // can just use the results in splitType.
4199  if (elementType == unqualElementType) {
4200    assert(quals.empty()); // from the recursive call
4201    quals = splitType.Quals;
4202    return QualType(splitType.Ty, 0);
4203  }
4204
4205  // Otherwise, add in the qualifiers from the outermost type, then
4206  // build the type back up.
4207  quals.addConsistentQualifiers(splitType.Quals);
4208
4209  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
4210    return getConstantArrayType(unqualElementType, CAT->getSize(),
4211                                CAT->getSizeModifier(), 0);
4212  }
4213
4214  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
4215    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
4216  }
4217
4218  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
4219    return getVariableArrayType(unqualElementType,
4220                                VAT->getSizeExpr(),
4221                                VAT->getSizeModifier(),
4222                                VAT->getIndexTypeCVRQualifiers(),
4223                                VAT->getBracketsRange());
4224  }
4225
4226  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
4227  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
4228                                    DSAT->getSizeModifier(), 0,
4229                                    SourceRange());
4230}
4231
4232/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
4233/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
4234/// they point to and return true. If T1 and T2 aren't pointer types
4235/// or pointer-to-member types, or if they are not similar at this
4236/// level, returns false and leaves T1 and T2 unchanged. Top-level
4237/// qualifiers on T1 and T2 are ignored. This function will typically
4238/// be called in a loop that successively "unwraps" pointer and
4239/// pointer-to-member types to compare them at each level.
4240bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
4241  const PointerType *T1PtrType = T1->getAs<PointerType>(),
4242                    *T2PtrType = T2->getAs<PointerType>();
4243  if (T1PtrType && T2PtrType) {
4244    T1 = T1PtrType->getPointeeType();
4245    T2 = T2PtrType->getPointeeType();
4246    return true;
4247  }
4248
4249  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
4250                          *T2MPType = T2->getAs<MemberPointerType>();
4251  if (T1MPType && T2MPType &&
4252      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
4253                             QualType(T2MPType->getClass(), 0))) {
4254    T1 = T1MPType->getPointeeType();
4255    T2 = T2MPType->getPointeeType();
4256    return true;
4257  }
4258
4259  if (getLangOpts().ObjC1) {
4260    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
4261                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
4262    if (T1OPType && T2OPType) {
4263      T1 = T1OPType->getPointeeType();
4264      T2 = T2OPType->getPointeeType();
4265      return true;
4266    }
4267  }
4268
4269  // FIXME: Block pointers, too?
4270
4271  return false;
4272}
4273
4274DeclarationNameInfo
4275ASTContext::getNameForTemplate(TemplateName Name,
4276                               SourceLocation NameLoc) const {
4277  switch (Name.getKind()) {
4278  case TemplateName::QualifiedTemplate:
4279  case TemplateName::Template:
4280    // DNInfo work in progress: CHECKME: what about DNLoc?
4281    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
4282                               NameLoc);
4283
4284  case TemplateName::OverloadedTemplate: {
4285    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
4286    // DNInfo work in progress: CHECKME: what about DNLoc?
4287    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
4288  }
4289
4290  case TemplateName::DependentTemplate: {
4291    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
4292    DeclarationName DName;
4293    if (DTN->isIdentifier()) {
4294      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
4295      return DeclarationNameInfo(DName, NameLoc);
4296    } else {
4297      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
4298      // DNInfo work in progress: FIXME: source locations?
4299      DeclarationNameLoc DNLoc;
4300      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
4301      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
4302      return DeclarationNameInfo(DName, NameLoc, DNLoc);
4303    }
4304  }
4305
4306  case TemplateName::SubstTemplateTemplateParm: {
4307    SubstTemplateTemplateParmStorage *subst
4308      = Name.getAsSubstTemplateTemplateParm();
4309    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
4310                               NameLoc);
4311  }
4312
4313  case TemplateName::SubstTemplateTemplateParmPack: {
4314    SubstTemplateTemplateParmPackStorage *subst
4315      = Name.getAsSubstTemplateTemplateParmPack();
4316    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
4317                               NameLoc);
4318  }
4319  }
4320
4321  llvm_unreachable("bad template name kind!");
4322}
4323
4324TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
4325  switch (Name.getKind()) {
4326  case TemplateName::QualifiedTemplate:
4327  case TemplateName::Template: {
4328    TemplateDecl *Template = Name.getAsTemplateDecl();
4329    if (TemplateTemplateParmDecl *TTP
4330          = dyn_cast<TemplateTemplateParmDecl>(Template))
4331      Template = getCanonicalTemplateTemplateParmDecl(TTP);
4332
4333    // The canonical template name is the canonical template declaration.
4334    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
4335  }
4336
4337  case TemplateName::OverloadedTemplate:
4338    llvm_unreachable("cannot canonicalize overloaded template");
4339
4340  case TemplateName::DependentTemplate: {
4341    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
4342    assert(DTN && "Non-dependent template names must refer to template decls.");
4343    return DTN->CanonicalTemplateName;
4344  }
4345
4346  case TemplateName::SubstTemplateTemplateParm: {
4347    SubstTemplateTemplateParmStorage *subst
4348      = Name.getAsSubstTemplateTemplateParm();
4349    return getCanonicalTemplateName(subst->getReplacement());
4350  }
4351
4352  case TemplateName::SubstTemplateTemplateParmPack: {
4353    SubstTemplateTemplateParmPackStorage *subst
4354                                  = Name.getAsSubstTemplateTemplateParmPack();
4355    TemplateTemplateParmDecl *canonParameter
4356      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
4357    TemplateArgument canonArgPack
4358      = getCanonicalTemplateArgument(subst->getArgumentPack());
4359    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
4360  }
4361  }
4362
4363  llvm_unreachable("bad template name!");
4364}
4365
4366bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
4367  X = getCanonicalTemplateName(X);
4368  Y = getCanonicalTemplateName(Y);
4369  return X.getAsVoidPointer() == Y.getAsVoidPointer();
4370}
4371
4372TemplateArgument
4373ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
4374  switch (Arg.getKind()) {
4375    case TemplateArgument::Null:
4376      return Arg;
4377
4378    case TemplateArgument::Expression:
4379      return Arg;
4380
4381    case TemplateArgument::Declaration: {
4382      ValueDecl *D = cast<ValueDecl>(Arg.getAsDecl()->getCanonicalDecl());
4383      return TemplateArgument(D, Arg.getParamTypeForDecl());
4384    }
4385
4386    case TemplateArgument::NullPtr:
4387      return TemplateArgument(getCanonicalType(Arg.getNullPtrType()),
4388                              /*isNullPtr*/true);
4389
4390    case TemplateArgument::Template:
4391      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
4392
4393    case TemplateArgument::TemplateExpansion:
4394      return TemplateArgument(getCanonicalTemplateName(
4395                                         Arg.getAsTemplateOrTemplatePattern()),
4396                              Arg.getNumTemplateExpansions());
4397
4398    case TemplateArgument::Integral:
4399      return TemplateArgument(Arg, getCanonicalType(Arg.getIntegralType()));
4400
4401    case TemplateArgument::Type:
4402      return TemplateArgument(getCanonicalType(Arg.getAsType()));
4403
4404    case TemplateArgument::Pack: {
4405      if (Arg.pack_size() == 0)
4406        return Arg;
4407
4408      TemplateArgument *CanonArgs
4409        = new (*this) TemplateArgument[Arg.pack_size()];
4410      unsigned Idx = 0;
4411      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
4412                                        AEnd = Arg.pack_end();
4413           A != AEnd; (void)++A, ++Idx)
4414        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
4415
4416      return TemplateArgument(llvm::makeArrayRef(CanonArgs, Arg.pack_size()));
4417    }
4418  }
4419
4420  // Silence GCC warning
4421  llvm_unreachable("Unhandled template argument kind");
4422}
4423
4424NestedNameSpecifier *
4425ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
4426  if (!NNS)
4427    return nullptr;
4428
4429  switch (NNS->getKind()) {
4430  case NestedNameSpecifier::Identifier:
4431    // Canonicalize the prefix but keep the identifier the same.
4432    return NestedNameSpecifier::Create(*this,
4433                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
4434                                       NNS->getAsIdentifier());
4435
4436  case NestedNameSpecifier::Namespace:
4437    // A namespace is canonical; build a nested-name-specifier with
4438    // this namespace and no prefix.
4439    return NestedNameSpecifier::Create(*this, nullptr,
4440                                 NNS->getAsNamespace()->getOriginalNamespace());
4441
4442  case NestedNameSpecifier::NamespaceAlias:
4443    // A namespace is canonical; build a nested-name-specifier with
4444    // this namespace and no prefix.
4445    return NestedNameSpecifier::Create(*this, nullptr,
4446                                    NNS->getAsNamespaceAlias()->getNamespace()
4447                                                      ->getOriginalNamespace());
4448
4449  case NestedNameSpecifier::TypeSpec:
4450  case NestedNameSpecifier::TypeSpecWithTemplate: {
4451    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
4452
4453    // If we have some kind of dependent-named type (e.g., "typename T::type"),
4454    // break it apart into its prefix and identifier, then reconsititute those
4455    // as the canonical nested-name-specifier. This is required to canonicalize
4456    // a dependent nested-name-specifier involving typedefs of dependent-name
4457    // types, e.g.,
4458    //   typedef typename T::type T1;
4459    //   typedef typename T1::type T2;
4460    if (const DependentNameType *DNT = T->getAs<DependentNameType>())
4461      return NestedNameSpecifier::Create(*this, DNT->getQualifier(),
4462                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
4463
4464    // Otherwise, just canonicalize the type, and force it to be a TypeSpec.
4465    // FIXME: Why are TypeSpec and TypeSpecWithTemplate distinct in the
4466    // first place?
4467    return NestedNameSpecifier::Create(*this, nullptr, false,
4468                                       const_cast<Type *>(T.getTypePtr()));
4469  }
4470
4471  case NestedNameSpecifier::Global:
4472  case NestedNameSpecifier::Super:
4473    // The global specifier and __super specifer are canonical and unique.
4474    return NNS;
4475  }
4476
4477  llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
4478}
4479
4480const ArrayType *ASTContext::getAsArrayType(QualType T) const {
4481  // Handle the non-qualified case efficiently.
4482  if (!T.hasLocalQualifiers()) {
4483    // Handle the common positive case fast.
4484    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
4485      return AT;
4486  }
4487
4488  // Handle the common negative case fast.
4489  if (!isa<ArrayType>(T.getCanonicalType()))
4490    return nullptr;
4491
4492  // Apply any qualifiers from the array type to the element type.  This
4493  // implements C99 6.7.3p8: "If the specification of an array type includes
4494  // any type qualifiers, the element type is so qualified, not the array type."
4495
4496  // If we get here, we either have type qualifiers on the type, or we have
4497  // sugar such as a typedef in the way.  If we have type qualifiers on the type
4498  // we must propagate them down into the element type.
4499
4500  SplitQualType split = T.getSplitDesugaredType();
4501  Qualifiers qs = split.Quals;
4502
4503  // If we have a simple case, just return now.
4504  const ArrayType *ATy = dyn_cast<ArrayType>(split.Ty);
4505  if (!ATy || qs.empty())
4506    return ATy;
4507
4508  // Otherwise, we have an array and we have qualifiers on it.  Push the
4509  // qualifiers into the array element type and return a new array type.
4510  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
4511
4512  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
4513    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
4514                                                CAT->getSizeModifier(),
4515                                           CAT->getIndexTypeCVRQualifiers()));
4516  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
4517    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
4518                                                  IAT->getSizeModifier(),
4519                                           IAT->getIndexTypeCVRQualifiers()));
4520
4521  if (const DependentSizedArrayType *DSAT
4522        = dyn_cast<DependentSizedArrayType>(ATy))
4523    return cast<ArrayType>(
4524                     getDependentSizedArrayType(NewEltTy,
4525                                                DSAT->getSizeExpr(),
4526                                                DSAT->getSizeModifier(),
4527                                              DSAT->getIndexTypeCVRQualifiers(),
4528                                                DSAT->getBracketsRange()));
4529
4530  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
4531  return cast<ArrayType>(getVariableArrayType(NewEltTy,
4532                                              VAT->getSizeExpr(),
4533                                              VAT->getSizeModifier(),
4534                                              VAT->getIndexTypeCVRQualifiers(),
4535                                              VAT->getBracketsRange()));
4536}
4537
4538QualType ASTContext::getAdjustedParameterType(QualType T) const {
4539  if (T->isArrayType() || T->isFunctionType())
4540    return getDecayedType(T);
4541  return T;
4542}
4543
4544QualType ASTContext::getSignatureParameterType(QualType T) const {
4545  T = getVariableArrayDecayedType(T);
4546  T = getAdjustedParameterType(T);
4547  return T.getUnqualifiedType();
4548}
4549
4550QualType ASTContext::getExceptionObjectType(QualType T) const {
4551  // C++ [except.throw]p3:
4552  //   A throw-expression initializes a temporary object, called the exception
4553  //   object, the type of which is determined by removing any top-level
4554  //   cv-qualifiers from the static type of the operand of throw and adjusting
4555  //   the type from "array of T" or "function returning T" to "pointer to T"
4556  //   or "pointer to function returning T", [...]
4557  T = getVariableArrayDecayedType(T);
4558  if (T->isArrayType() || T->isFunctionType())
4559    T = getDecayedType(T);
4560  return T.getUnqualifiedType();
4561}
4562
4563/// getArrayDecayedType - Return the properly qualified result of decaying the
4564/// specified array type to a pointer.  This operation is non-trivial when
4565/// handling typedefs etc.  The canonical type of "T" must be an array type,
4566/// this returns a pointer to a properly qualified element of the array.
4567///
4568/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
4569QualType ASTContext::getArrayDecayedType(QualType Ty) const {
4570  // Get the element type with 'getAsArrayType' so that we don't lose any
4571  // typedefs in the element type of the array.  This also handles propagation
4572  // of type qualifiers from the array type into the element type if present
4573  // (C99 6.7.3p8).
4574  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
4575  assert(PrettyArrayType && "Not an array type!");
4576
4577  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
4578
4579  // int x[restrict 4] ->  int *restrict
4580  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
4581}
4582
4583QualType ASTContext::getBaseElementType(const ArrayType *array) const {
4584  return getBaseElementType(array->getElementType());
4585}
4586
4587QualType ASTContext::getBaseElementType(QualType type) const {
4588  Qualifiers qs;
4589  while (true) {
4590    SplitQualType split = type.getSplitDesugaredType();
4591    const ArrayType *array = split.Ty->getAsArrayTypeUnsafe();
4592    if (!array) break;
4593
4594    type = array->getElementType();
4595    qs.addConsistentQualifiers(split.Quals);
4596  }
4597
4598  return getQualifiedType(type, qs);
4599}
4600
4601/// getConstantArrayElementCount - Returns number of constant array elements.
4602uint64_t
4603ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
4604  uint64_t ElementCount = 1;
4605  do {
4606    ElementCount *= CA->getSize().getZExtValue();
4607    CA = dyn_cast_or_null<ConstantArrayType>(
4608      CA->getElementType()->getAsArrayTypeUnsafe());
4609  } while (CA);
4610  return ElementCount;
4611}
4612
4613/// getFloatingRank - Return a relative rank for floating point types.
4614/// This routine will assert if passed a built-in type that isn't a float.
4615static FloatingRank getFloatingRank(QualType T) {
4616  if (const ComplexType *CT = T->getAs<ComplexType>())
4617    return getFloatingRank(CT->getElementType());
4618
4619  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
4620  switch (T->getAs<BuiltinType>()->getKind()) {
4621  default: llvm_unreachable("getFloatingRank(): not a floating type");
4622  case BuiltinType::Half:       return HalfRank;
4623  case BuiltinType::Float:      return FloatRank;
4624  case BuiltinType::Double:     return DoubleRank;
4625  case BuiltinType::LongDouble: return LongDoubleRank;
4626  }
4627}
4628
4629/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
4630/// point or a complex type (based on typeDomain/typeSize).
4631/// 'typeDomain' is a real floating point or complex type.
4632/// 'typeSize' is a real floating point or complex type.
4633QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
4634                                                       QualType Domain) const {
4635  FloatingRank EltRank = getFloatingRank(Size);
4636  if (Domain->isComplexType()) {
4637    switch (EltRank) {
4638    case HalfRank: llvm_unreachable("Complex half is not supported");
4639    case FloatRank:      return FloatComplexTy;
4640    case DoubleRank:     return DoubleComplexTy;
4641    case LongDoubleRank: return LongDoubleComplexTy;
4642    }
4643  }
4644
4645  assert(Domain->isRealFloatingType() && "Unknown domain!");
4646  switch (EltRank) {
4647  case HalfRank:       return HalfTy;
4648  case FloatRank:      return FloatTy;
4649  case DoubleRank:     return DoubleTy;
4650  case LongDoubleRank: return LongDoubleTy;
4651  }
4652  llvm_unreachable("getFloatingRank(): illegal value for rank");
4653}
4654
4655/// getFloatingTypeOrder - Compare the rank of the two specified floating
4656/// point types, ignoring the domain of the type (i.e. 'double' ==
4657/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
4658/// LHS < RHS, return -1.
4659int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
4660  FloatingRank LHSR = getFloatingRank(LHS);
4661  FloatingRank RHSR = getFloatingRank(RHS);
4662
4663  if (LHSR == RHSR)
4664    return 0;
4665  if (LHSR > RHSR)
4666    return 1;
4667  return -1;
4668}
4669
4670/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
4671/// routine will assert if passed a built-in type that isn't an integer or enum,
4672/// or if it is not canonicalized.
4673unsigned ASTContext::getIntegerRank(const Type *T) const {
4674  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
4675
4676  switch (cast<BuiltinType>(T)->getKind()) {
4677  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
4678  case BuiltinType::Bool:
4679    return 1 + (getIntWidth(BoolTy) << 3);
4680  case BuiltinType::Char_S:
4681  case BuiltinType::Char_U:
4682  case BuiltinType::SChar:
4683  case BuiltinType::UChar:
4684    return 2 + (getIntWidth(CharTy) << 3);
4685  case BuiltinType::Short:
4686  case BuiltinType::UShort:
4687    return 3 + (getIntWidth(ShortTy) << 3);
4688  case BuiltinType::Int:
4689  case BuiltinType::UInt:
4690    return 4 + (getIntWidth(IntTy) << 3);
4691  case BuiltinType::Long:
4692  case BuiltinType::ULong:
4693    return 5 + (getIntWidth(LongTy) << 3);
4694  case BuiltinType::LongLong:
4695  case BuiltinType::ULongLong:
4696    return 6 + (getIntWidth(LongLongTy) << 3);
4697  case BuiltinType::Int128:
4698  case BuiltinType::UInt128:
4699    return 7 + (getIntWidth(Int128Ty) << 3);
4700  }
4701}
4702
4703/// \brief Whether this is a promotable bitfield reference according
4704/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
4705///
4706/// \returns the type this bit-field will promote to, or NULL if no
4707/// promotion occurs.
4708QualType ASTContext::isPromotableBitField(Expr *E) const {
4709  if (E->isTypeDependent() || E->isValueDependent())
4710    return QualType();
4711
4712  // FIXME: We should not do this unless E->refersToBitField() is true. This
4713  // matters in C where getSourceBitField() will find bit-fields for various
4714  // cases where the source expression is not a bit-field designator.
4715
4716  FieldDecl *Field = E->getSourceBitField(); // FIXME: conditional bit-fields?
4717  if (!Field)
4718    return QualType();
4719
4720  QualType FT = Field->getType();
4721
4722  uint64_t BitWidth = Field->getBitWidthValue(*this);
4723  uint64_t IntSize = getTypeSize(IntTy);
4724  // C++ [conv.prom]p5:
4725  //   A prvalue for an integral bit-field can be converted to a prvalue of type
4726  //   int if int can represent all the values of the bit-field; otherwise, it
4727  //   can be converted to unsigned int if unsigned int can represent all the
4728  //   values of the bit-field. If the bit-field is larger yet, no integral
4729  //   promotion applies to it.
4730  // C11 6.3.1.1/2:
4731  //   [For a bit-field of type _Bool, int, signed int, or unsigned int:]
4732  //   If an int can represent all values of the original type (as restricted by
4733  //   the width, for a bit-field), the value is converted to an int; otherwise,
4734  //   it is converted to an unsigned int.
4735  //
4736  // FIXME: C does not permit promotion of a 'long : 3' bitfield to int.
4737  //        We perform that promotion here to match GCC and C++.
4738  if (BitWidth < IntSize)
4739    return IntTy;
4740
4741  if (BitWidth == IntSize)
4742    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
4743
4744  // Types bigger than int are not subject to promotions, and therefore act
4745  // like the base type. GCC has some weird bugs in this area that we
4746  // deliberately do not follow (GCC follows a pre-standard resolution to
4747  // C's DR315 which treats bit-width as being part of the type, and this leaks
4748  // into their semantics in some cases).
4749  return QualType();
4750}
4751
4752/// getPromotedIntegerType - Returns the type that Promotable will
4753/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
4754/// integer type.
4755QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
4756  assert(!Promotable.isNull());
4757  assert(Promotable->isPromotableIntegerType());
4758  if (const EnumType *ET = Promotable->getAs<EnumType>())
4759    return ET->getDecl()->getPromotionType();
4760
4761  if (const BuiltinType *BT = Promotable->getAs<BuiltinType>()) {
4762    // C++ [conv.prom]: A prvalue of type char16_t, char32_t, or wchar_t
4763    // (3.9.1) can be converted to a prvalue of the first of the following
4764    // types that can represent all the values of its underlying type:
4765    // int, unsigned int, long int, unsigned long int, long long int, or
4766    // unsigned long long int [...]
4767    // FIXME: Is there some better way to compute this?
4768    if (BT->getKind() == BuiltinType::WChar_S ||
4769        BT->getKind() == BuiltinType::WChar_U ||
4770        BT->getKind() == BuiltinType::Char16 ||
4771        BT->getKind() == BuiltinType::Char32) {
4772      bool FromIsSigned = BT->getKind() == BuiltinType::WChar_S;
4773      uint64_t FromSize = getTypeSize(BT);
4774      QualType PromoteTypes[] = { IntTy, UnsignedIntTy, LongTy, UnsignedLongTy,
4775                                  LongLongTy, UnsignedLongLongTy };
4776      for (size_t Idx = 0; Idx < llvm::array_lengthof(PromoteTypes); ++Idx) {
4777        uint64_t ToSize = getTypeSize(PromoteTypes[Idx]);
4778        if (FromSize < ToSize ||
4779            (FromSize == ToSize &&
4780             FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType()))
4781          return PromoteTypes[Idx];
4782      }
4783      llvm_unreachable("char type should fit into long long");
4784    }
4785  }
4786
4787  // At this point, we should have a signed or unsigned integer type.
4788  if (Promotable->isSignedIntegerType())
4789    return IntTy;
4790  uint64_t PromotableSize = getIntWidth(Promotable);
4791  uint64_t IntSize = getIntWidth(IntTy);
4792  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
4793  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
4794}
4795
4796/// \brief Recurses in pointer/array types until it finds an objc retainable
4797/// type and returns its ownership.
4798Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
4799  while (!T.isNull()) {
4800    if (T.getObjCLifetime() != Qualifiers::OCL_None)
4801      return T.getObjCLifetime();
4802    if (T->isArrayType())
4803      T = getBaseElementType(T);
4804    else if (const PointerType *PT = T->getAs<PointerType>())
4805      T = PT->getPointeeType();
4806    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4807      T = RT->getPointeeType();
4808    else
4809      break;
4810  }
4811
4812  return Qualifiers::OCL_None;
4813}
4814
4815static const Type *getIntegerTypeForEnum(const EnumType *ET) {
4816  // Incomplete enum types are not treated as integer types.
4817  // FIXME: In C++, enum types are never integer types.
4818  if (ET->getDecl()->isComplete() && !ET->getDecl()->isScoped())
4819    return ET->getDecl()->getIntegerType().getTypePtr();
4820  return nullptr;
4821}
4822
4823/// getIntegerTypeOrder - Returns the highest ranked integer type:
4824/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
4825/// LHS < RHS, return -1.
4826int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
4827  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
4828  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
4829
4830  // Unwrap enums to their underlying type.
4831  if (const EnumType *ET = dyn_cast<EnumType>(LHSC))
4832    LHSC = getIntegerTypeForEnum(ET);
4833  if (const EnumType *ET = dyn_cast<EnumType>(RHSC))
4834    RHSC = getIntegerTypeForEnum(ET);
4835
4836  if (LHSC == RHSC) return 0;
4837
4838  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
4839  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
4840
4841  unsigned LHSRank = getIntegerRank(LHSC);
4842  unsigned RHSRank = getIntegerRank(RHSC);
4843
4844  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
4845    if (LHSRank == RHSRank) return 0;
4846    return LHSRank > RHSRank ? 1 : -1;
4847  }
4848
4849  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
4850  if (LHSUnsigned) {
4851    // If the unsigned [LHS] type is larger, return it.
4852    if (LHSRank >= RHSRank)
4853      return 1;
4854
4855    // If the signed type can represent all values of the unsigned type, it
4856    // wins.  Because we are dealing with 2's complement and types that are
4857    // powers of two larger than each other, this is always safe.
4858    return -1;
4859  }
4860
4861  // If the unsigned [RHS] type is larger, return it.
4862  if (RHSRank >= LHSRank)
4863    return -1;
4864
4865  // If the signed type can represent all values of the unsigned type, it
4866  // wins.  Because we are dealing with 2's complement and types that are
4867  // powers of two larger than each other, this is always safe.
4868  return 1;
4869}
4870
4871// getCFConstantStringType - Return the type used for constant CFStrings.
4872QualType ASTContext::getCFConstantStringType() const {
4873  if (!CFConstantStringTypeDecl) {
4874    CFConstantStringTypeDecl = buildImplicitRecord("NSConstantString");
4875    CFConstantStringTypeDecl->startDefinition();
4876
4877    QualType FieldTypes[4];
4878
4879    // const int *isa;
4880    FieldTypes[0] = getPointerType(IntTy.withConst());
4881    // int flags;
4882    FieldTypes[1] = IntTy;
4883    // const char *str;
4884    FieldTypes[2] = getPointerType(CharTy.withConst());
4885    // long length;
4886    FieldTypes[3] = LongTy;
4887
4888    // Create fields
4889    for (unsigned i = 0; i < 4; ++i) {
4890      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
4891                                           SourceLocation(),
4892                                           SourceLocation(), nullptr,
4893                                           FieldTypes[i], /*TInfo=*/nullptr,
4894                                           /*BitWidth=*/nullptr,
4895                                           /*Mutable=*/false,
4896                                           ICIS_NoInit);
4897      Field->setAccess(AS_public);
4898      CFConstantStringTypeDecl->addDecl(Field);
4899    }
4900
4901    CFConstantStringTypeDecl->completeDefinition();
4902  }
4903
4904  return getTagDeclType(CFConstantStringTypeDecl);
4905}
4906
4907QualType ASTContext::getObjCSuperType() const {
4908  if (ObjCSuperType.isNull()) {
4909    RecordDecl *ObjCSuperTypeDecl = buildImplicitRecord("objc_super");
4910    TUDecl->addDecl(ObjCSuperTypeDecl);
4911    ObjCSuperType = getTagDeclType(ObjCSuperTypeDecl);
4912  }
4913  return ObjCSuperType;
4914}
4915
4916void ASTContext::setCFConstantStringType(QualType T) {
4917  const RecordType *Rec = T->getAs<RecordType>();
4918  assert(Rec && "Invalid CFConstantStringType");
4919  CFConstantStringTypeDecl = Rec->getDecl();
4920}
4921
4922QualType ASTContext::getBlockDescriptorType() const {
4923  if (BlockDescriptorType)
4924    return getTagDeclType(BlockDescriptorType);
4925
4926  RecordDecl *RD;
4927  // FIXME: Needs the FlagAppleBlock bit.
4928  RD = buildImplicitRecord("__block_descriptor");
4929  RD->startDefinition();
4930
4931  QualType FieldTypes[] = {
4932    UnsignedLongTy,
4933    UnsignedLongTy,
4934  };
4935
4936  static const char *const FieldNames[] = {
4937    "reserved",
4938    "Size"
4939  };
4940
4941  for (size_t i = 0; i < 2; ++i) {
4942    FieldDecl *Field = FieldDecl::Create(
4943        *this, RD, SourceLocation(), SourceLocation(),
4944        &Idents.get(FieldNames[i]), FieldTypes[i], /*TInfo=*/nullptr,
4945        /*BitWidth=*/nullptr, /*Mutable=*/false, ICIS_NoInit);
4946    Field->setAccess(AS_public);
4947    RD->addDecl(Field);
4948  }
4949
4950  RD->completeDefinition();
4951
4952  BlockDescriptorType = RD;
4953
4954  return getTagDeclType(BlockDescriptorType);
4955}
4956
4957QualType ASTContext::getBlockDescriptorExtendedType() const {
4958  if (BlockDescriptorExtendedType)
4959    return getTagDeclType(BlockDescriptorExtendedType);
4960
4961  RecordDecl *RD;
4962  // FIXME: Needs the FlagAppleBlock bit.
4963  RD = buildImplicitRecord("__block_descriptor_withcopydispose");
4964  RD->startDefinition();
4965
4966  QualType FieldTypes[] = {
4967    UnsignedLongTy,
4968    UnsignedLongTy,
4969    getPointerType(VoidPtrTy),
4970    getPointerType(VoidPtrTy)
4971  };
4972
4973  static const char *const FieldNames[] = {
4974    "reserved",
4975    "Size",
4976    "CopyFuncPtr",
4977    "DestroyFuncPtr"
4978  };
4979
4980  for (size_t i = 0; i < 4; ++i) {
4981    FieldDecl *Field = FieldDecl::Create(
4982        *this, RD, SourceLocation(), SourceLocation(),
4983        &Idents.get(FieldNames[i]), FieldTypes[i], /*TInfo=*/nullptr,
4984        /*BitWidth=*/nullptr,
4985        /*Mutable=*/false, ICIS_NoInit);
4986    Field->setAccess(AS_public);
4987    RD->addDecl(Field);
4988  }
4989
4990  RD->completeDefinition();
4991
4992  BlockDescriptorExtendedType = RD;
4993  return getTagDeclType(BlockDescriptorExtendedType);
4994}
4995
4996/// BlockRequiresCopying - Returns true if byref variable "D" of type "Ty"
4997/// requires copy/dispose. Note that this must match the logic
4998/// in buildByrefHelpers.
4999bool ASTContext::BlockRequiresCopying(QualType Ty,
5000                                      const VarDecl *D) {
5001  if (const CXXRecordDecl *record = Ty->getAsCXXRecordDecl()) {
5002    const Expr *copyExpr = getBlockVarCopyInits(D);
5003    if (!copyExpr && record->hasTrivialDestructor()) return false;
5004
5005    return true;
5006  }
5007
5008  if (!Ty->isObjCRetainableType()) return false;
5009
5010  Qualifiers qs = Ty.getQualifiers();
5011
5012  // If we have lifetime, that dominates.
5013  if (Qualifiers::ObjCLifetime lifetime = qs.getObjCLifetime()) {
5014    switch (lifetime) {
5015      case Qualifiers::OCL_None: llvm_unreachable("impossible");
5016
5017      // These are just bits as far as the runtime is concerned.
5018      case Qualifiers::OCL_ExplicitNone:
5019      case Qualifiers::OCL_Autoreleasing:
5020        return false;
5021
5022      // Tell the runtime that this is ARC __weak, called by the
5023      // byref routines.
5024      case Qualifiers::OCL_Weak:
5025      // ARC __strong __block variables need to be retained.
5026      case Qualifiers::OCL_Strong:
5027        return true;
5028    }
5029    llvm_unreachable("fell out of lifetime switch!");
5030  }
5031  return (Ty->isBlockPointerType() || isObjCNSObjectType(Ty) ||
5032          Ty->isObjCObjectPointerType());
5033}
5034
5035bool ASTContext::getByrefLifetime(QualType Ty,
5036                              Qualifiers::ObjCLifetime &LifeTime,
5037                              bool &HasByrefExtendedLayout) const {
5038
5039  if (!getLangOpts().ObjC1 ||
5040      getLangOpts().getGC() != LangOptions::NonGC)
5041    return false;
5042
5043  HasByrefExtendedLayout = false;
5044  if (Ty->isRecordType()) {
5045    HasByrefExtendedLayout = true;
5046    LifeTime = Qualifiers::OCL_None;
5047  } else if ((LifeTime = Ty.getObjCLifetime())) {
5048    // Honor the ARC qualifiers.
5049  } else if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType()) {
5050    // The MRR rule.
5051    LifeTime = Qualifiers::OCL_ExplicitNone;
5052  } else {
5053    LifeTime = Qualifiers::OCL_None;
5054  }
5055  return true;
5056}
5057
5058TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
5059  if (!ObjCInstanceTypeDecl)
5060    ObjCInstanceTypeDecl =
5061        buildImplicitTypedef(getObjCIdType(), "instancetype");
5062  return ObjCInstanceTypeDecl;
5063}
5064
5065// This returns true if a type has been typedefed to BOOL:
5066// typedef <type> BOOL;
5067static bool isTypeTypedefedAsBOOL(QualType T) {
5068  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
5069    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
5070      return II->isStr("BOOL");
5071
5072  return false;
5073}
5074
5075/// getObjCEncodingTypeSize returns size of type for objective-c encoding
5076/// purpose.
5077CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
5078  if (!type->isIncompleteArrayType() && type->isIncompleteType())
5079    return CharUnits::Zero();
5080
5081  CharUnits sz = getTypeSizeInChars(type);
5082
5083  // Make all integer and enum types at least as large as an int
5084  if (sz.isPositive() && type->isIntegralOrEnumerationType())
5085    sz = std::max(sz, getTypeSizeInChars(IntTy));
5086  // Treat arrays as pointers, since that's how they're passed in.
5087  else if (type->isArrayType())
5088    sz = getTypeSizeInChars(VoidPtrTy);
5089  return sz;
5090}
5091
5092bool ASTContext::isMSStaticDataMemberInlineDefinition(const VarDecl *VD) const {
5093  return getTargetInfo().getCXXABI().isMicrosoft() &&
5094         VD->isStaticDataMember() &&
5095         VD->getType()->isIntegralOrEnumerationType() &&
5096         !VD->getFirstDecl()->isOutOfLine() && VD->getFirstDecl()->hasInit();
5097}
5098
5099static inline
5100std::string charUnitsToString(const CharUnits &CU) {
5101  return llvm::itostr(CU.getQuantity());
5102}
5103
5104/// getObjCEncodingForBlock - Return the encoded type for this block
5105/// declaration.
5106std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
5107  std::string S;
5108
5109  const BlockDecl *Decl = Expr->getBlockDecl();
5110  QualType BlockTy =
5111      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
5112  // Encode result type.
5113  if (getLangOpts().EncodeExtendedBlockSig)
5114    getObjCEncodingForMethodParameter(
5115        Decl::OBJC_TQ_None, BlockTy->getAs<FunctionType>()->getReturnType(), S,
5116        true /*Extended*/);
5117  else
5118    getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getReturnType(), S);
5119  // Compute size of all parameters.
5120  // Start with computing size of a pointer in number of bytes.
5121  // FIXME: There might(should) be a better way of doing this computation!
5122  SourceLocation Loc;
5123  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
5124  CharUnits ParmOffset = PtrSize;
5125  for (auto PI : Decl->params()) {
5126    QualType PType = PI->getType();
5127    CharUnits sz = getObjCEncodingTypeSize(PType);
5128    if (sz.isZero())
5129      continue;
5130    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
5131    ParmOffset += sz;
5132  }
5133  // Size of the argument frame
5134  S += charUnitsToString(ParmOffset);
5135  // Block pointer and offset.
5136  S += "@?0";
5137
5138  // Argument types.
5139  ParmOffset = PtrSize;
5140  for (auto PVDecl : Decl->params()) {
5141    QualType PType = PVDecl->getOriginalType();
5142    if (const ArrayType *AT =
5143          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
5144      // Use array's original type only if it has known number of
5145      // elements.
5146      if (!isa<ConstantArrayType>(AT))
5147        PType = PVDecl->getType();
5148    } else if (PType->isFunctionType())
5149      PType = PVDecl->getType();
5150    if (getLangOpts().EncodeExtendedBlockSig)
5151      getObjCEncodingForMethodParameter(Decl::OBJC_TQ_None, PType,
5152                                      S, true /*Extended*/);
5153    else
5154      getObjCEncodingForType(PType, S);
5155    S += charUnitsToString(ParmOffset);
5156    ParmOffset += getObjCEncodingTypeSize(PType);
5157  }
5158
5159  return S;
5160}
5161
5162bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
5163                                                std::string& S) {
5164  // Encode result type.
5165  getObjCEncodingForType(Decl->getReturnType(), S);
5166  CharUnits ParmOffset;
5167  // Compute size of all parameters.
5168  for (auto PI : Decl->params()) {
5169    QualType PType = PI->getType();
5170    CharUnits sz = getObjCEncodingTypeSize(PType);
5171    if (sz.isZero())
5172      continue;
5173
5174    assert (sz.isPositive() &&
5175        "getObjCEncodingForFunctionDecl - Incomplete param type");
5176    ParmOffset += sz;
5177  }
5178  S += charUnitsToString(ParmOffset);
5179  ParmOffset = CharUnits::Zero();
5180
5181  // Argument types.
5182  for (auto PVDecl : Decl->params()) {
5183    QualType PType = PVDecl->getOriginalType();
5184    if (const ArrayType *AT =
5185          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
5186      // Use array's original type only if it has known number of
5187      // elements.
5188      if (!isa<ConstantArrayType>(AT))
5189        PType = PVDecl->getType();
5190    } else if (PType->isFunctionType())
5191      PType = PVDecl->getType();
5192    getObjCEncodingForType(PType, S);
5193    S += charUnitsToString(ParmOffset);
5194    ParmOffset += getObjCEncodingTypeSize(PType);
5195  }
5196
5197  return false;
5198}
5199
5200/// getObjCEncodingForMethodParameter - Return the encoded type for a single
5201/// method parameter or return type. If Extended, include class names and
5202/// block object types.
5203void ASTContext::getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
5204                                                   QualType T, std::string& S,
5205                                                   bool Extended) const {
5206  // Encode type qualifer, 'in', 'inout', etc. for the parameter.
5207  getObjCEncodingForTypeQualifier(QT, S);
5208  // Encode parameter type.
5209  getObjCEncodingForTypeImpl(T, S, true, true, nullptr,
5210                             true     /*OutermostType*/,
5211                             false    /*EncodingProperty*/,
5212                             false    /*StructField*/,
5213                             Extended /*EncodeBlockParameters*/,
5214                             Extended /*EncodeClassNames*/);
5215}
5216
5217/// getObjCEncodingForMethodDecl - Return the encoded type for this method
5218/// declaration.
5219bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
5220                                              std::string& S,
5221                                              bool Extended) const {
5222  // FIXME: This is not very efficient.
5223  // Encode return type.
5224  getObjCEncodingForMethodParameter(Decl->getObjCDeclQualifier(),
5225                                    Decl->getReturnType(), S, Extended);
5226  // Compute size of all parameters.
5227  // Start with computing size of a pointer in number of bytes.
5228  // FIXME: There might(should) be a better way of doing this computation!
5229  SourceLocation Loc;
5230  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
5231  // The first two arguments (self and _cmd) are pointers; account for
5232  // their size.
5233  CharUnits ParmOffset = 2 * PtrSize;
5234  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
5235       E = Decl->sel_param_end(); PI != E; ++PI) {
5236    QualType PType = (*PI)->getType();
5237    CharUnits sz = getObjCEncodingTypeSize(PType);
5238    if (sz.isZero())
5239      continue;
5240
5241    assert (sz.isPositive() &&
5242        "getObjCEncodingForMethodDecl - Incomplete param type");
5243    ParmOffset += sz;
5244  }
5245  S += charUnitsToString(ParmOffset);
5246  S += "@0:";
5247  S += charUnitsToString(PtrSize);
5248
5249  // Argument types.
5250  ParmOffset = 2 * PtrSize;
5251  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
5252       E = Decl->sel_param_end(); PI != E; ++PI) {
5253    const ParmVarDecl *PVDecl = *PI;
5254    QualType PType = PVDecl->getOriginalType();
5255    if (const ArrayType *AT =
5256          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
5257      // Use array's original type only if it has known number of
5258      // elements.
5259      if (!isa<ConstantArrayType>(AT))
5260        PType = PVDecl->getType();
5261    } else if (PType->isFunctionType())
5262      PType = PVDecl->getType();
5263    getObjCEncodingForMethodParameter(PVDecl->getObjCDeclQualifier(),
5264                                      PType, S, Extended);
5265    S += charUnitsToString(ParmOffset);
5266    ParmOffset += getObjCEncodingTypeSize(PType);
5267  }
5268
5269  return false;
5270}
5271
5272ObjCPropertyImplDecl *
5273ASTContext::getObjCPropertyImplDeclForPropertyDecl(
5274                                      const ObjCPropertyDecl *PD,
5275                                      const Decl *Container) const {
5276  if (!Container)
5277    return nullptr;
5278  if (const ObjCCategoryImplDecl *CID =
5279      dyn_cast<ObjCCategoryImplDecl>(Container)) {
5280    for (auto *PID : CID->property_impls())
5281      if (PID->getPropertyDecl() == PD)
5282        return PID;
5283  } else {
5284    const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
5285    for (auto *PID : OID->property_impls())
5286      if (PID->getPropertyDecl() == PD)
5287        return PID;
5288  }
5289  return nullptr;
5290}
5291
5292/// getObjCEncodingForPropertyDecl - Return the encoded type for this
5293/// property declaration. If non-NULL, Container must be either an
5294/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
5295/// NULL when getting encodings for protocol properties.
5296/// Property attributes are stored as a comma-delimited C string. The simple
5297/// attributes readonly and bycopy are encoded as single characters. The
5298/// parametrized attributes, getter=name, setter=name, and ivar=name, are
5299/// encoded as single characters, followed by an identifier. Property types
5300/// are also encoded as a parametrized attribute. The characters used to encode
5301/// these attributes are defined by the following enumeration:
5302/// @code
5303/// enum PropertyAttributes {
5304/// kPropertyReadOnly = 'R',   // property is read-only.
5305/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
5306/// kPropertyByref = '&',  // property is a reference to the value last assigned
5307/// kPropertyDynamic = 'D',    // property is dynamic
5308/// kPropertyGetter = 'G',     // followed by getter selector name
5309/// kPropertySetter = 'S',     // followed by setter selector name
5310/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
5311/// kPropertyType = 'T'              // followed by old-style type encoding.
5312/// kPropertyWeak = 'W'              // 'weak' property
5313/// kPropertyStrong = 'P'            // property GC'able
5314/// kPropertyNonAtomic = 'N'         // property non-atomic
5315/// };
5316/// @endcode
5317void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
5318                                                const Decl *Container,
5319                                                std::string& S) const {
5320  // Collect information from the property implementation decl(s).
5321  bool Dynamic = false;
5322  ObjCPropertyImplDecl *SynthesizePID = nullptr;
5323
5324  if (ObjCPropertyImplDecl *PropertyImpDecl =
5325      getObjCPropertyImplDeclForPropertyDecl(PD, Container)) {
5326    if (PropertyImpDecl->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
5327      Dynamic = true;
5328    else
5329      SynthesizePID = PropertyImpDecl;
5330  }
5331
5332  // FIXME: This is not very efficient.
5333  S = "T";
5334
5335  // Encode result type.
5336  // GCC has some special rules regarding encoding of properties which
5337  // closely resembles encoding of ivars.
5338  getObjCEncodingForPropertyType(PD->getType(), S);
5339
5340  if (PD->isReadOnly()) {
5341    S += ",R";
5342    if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_copy)
5343      S += ",C";
5344    if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_retain)
5345      S += ",&";
5346    if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_weak)
5347      S += ",W";
5348  } else {
5349    switch (PD->getSetterKind()) {
5350    case ObjCPropertyDecl::Assign: break;
5351    case ObjCPropertyDecl::Copy:   S += ",C"; break;
5352    case ObjCPropertyDecl::Retain: S += ",&"; break;
5353    case ObjCPropertyDecl::Weak:   S += ",W"; break;
5354    }
5355  }
5356
5357  // It really isn't clear at all what this means, since properties
5358  // are "dynamic by default".
5359  if (Dynamic)
5360    S += ",D";
5361
5362  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
5363    S += ",N";
5364
5365  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
5366    S += ",G";
5367    S += PD->getGetterName().getAsString();
5368  }
5369
5370  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
5371    S += ",S";
5372    S += PD->getSetterName().getAsString();
5373  }
5374
5375  if (SynthesizePID) {
5376    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
5377    S += ",V";
5378    S += OID->getNameAsString();
5379  }
5380
5381  // FIXME: OBJCGC: weak & strong
5382}
5383
5384/// getLegacyIntegralTypeEncoding -
5385/// Another legacy compatibility encoding: 32-bit longs are encoded as
5386/// 'l' or 'L' , but not always.  For typedefs, we need to use
5387/// 'i' or 'I' instead if encoding a struct field, or a pointer!
5388///
5389void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
5390  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
5391    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
5392      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
5393        PointeeTy = UnsignedIntTy;
5394      else
5395        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
5396          PointeeTy = IntTy;
5397    }
5398  }
5399}
5400
5401void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
5402                                        const FieldDecl *Field,
5403                                        QualType *NotEncodedT) const {
5404  // We follow the behavior of gcc, expanding structures which are
5405  // directly pointed to, and expanding embedded structures. Note that
5406  // these rules are sufficient to prevent recursive encoding of the
5407  // same type.
5408  getObjCEncodingForTypeImpl(T, S, true, true, Field,
5409                             true /* outermost type */, false, false,
5410                             false, false, false, NotEncodedT);
5411}
5412
5413void ASTContext::getObjCEncodingForPropertyType(QualType T,
5414                                                std::string& S) const {
5415  // Encode result type.
5416  // GCC has some special rules regarding encoding of properties which
5417  // closely resembles encoding of ivars.
5418  getObjCEncodingForTypeImpl(T, S, true, true, nullptr,
5419                             true /* outermost type */,
5420                             true /* encoding property */);
5421}
5422
5423static char getObjCEncodingForPrimitiveKind(const ASTContext *C,
5424                                            BuiltinType::Kind kind) {
5425    switch (kind) {
5426    case BuiltinType::Void:       return 'v';
5427    case BuiltinType::Bool:       return 'B';
5428    case BuiltinType::Char_U:
5429    case BuiltinType::UChar:      return 'C';
5430    case BuiltinType::Char16:
5431    case BuiltinType::UShort:     return 'S';
5432    case BuiltinType::Char32:
5433    case BuiltinType::UInt:       return 'I';
5434    case BuiltinType::ULong:
5435        return C->getTargetInfo().getLongWidth() == 32 ? 'L' : 'Q';
5436    case BuiltinType::UInt128:    return 'T';
5437    case BuiltinType::ULongLong:  return 'Q';
5438    case BuiltinType::Char_S:
5439    case BuiltinType::SChar:      return 'c';
5440    case BuiltinType::Short:      return 's';
5441    case BuiltinType::WChar_S:
5442    case BuiltinType::WChar_U:
5443    case BuiltinType::Int:        return 'i';
5444    case BuiltinType::Long:
5445      return C->getTargetInfo().getLongWidth() == 32 ? 'l' : 'q';
5446    case BuiltinType::LongLong:   return 'q';
5447    case BuiltinType::Int128:     return 't';
5448    case BuiltinType::Float:      return 'f';
5449    case BuiltinType::Double:     return 'd';
5450    case BuiltinType::LongDouble: return 'D';
5451    case BuiltinType::NullPtr:    return '*'; // like char*
5452
5453    case BuiltinType::Half:
5454      // FIXME: potentially need @encodes for these!
5455      return ' ';
5456
5457    case BuiltinType::ObjCId:
5458    case BuiltinType::ObjCClass:
5459    case BuiltinType::ObjCSel:
5460      llvm_unreachable("@encoding ObjC primitive type");
5461
5462    // OpenCL and placeholder types don't need @encodings.
5463    case BuiltinType::OCLImage1d:
5464    case BuiltinType::OCLImage1dArray:
5465    case BuiltinType::OCLImage1dBuffer:
5466    case BuiltinType::OCLImage2d:
5467    case BuiltinType::OCLImage2dArray:
5468    case BuiltinType::OCLImage2dDepth:
5469    case BuiltinType::OCLImage2dArrayDepth:
5470    case BuiltinType::OCLImage2dMSAA:
5471    case BuiltinType::OCLImage2dArrayMSAA:
5472    case BuiltinType::OCLImage2dMSAADepth:
5473    case BuiltinType::OCLImage2dArrayMSAADepth:
5474    case BuiltinType::OCLImage3d:
5475    case BuiltinType::OCLEvent:
5476    case BuiltinType::OCLClkEvent:
5477    case BuiltinType::OCLQueue:
5478    case BuiltinType::OCLNDRange:
5479    case BuiltinType::OCLReserveID:
5480    case BuiltinType::OCLSampler:
5481    case BuiltinType::Dependent:
5482#define BUILTIN_TYPE(KIND, ID)
5483#define PLACEHOLDER_TYPE(KIND, ID) \
5484    case BuiltinType::KIND:
5485#include "clang/AST/BuiltinTypes.def"
5486      llvm_unreachable("invalid builtin type for @encode");
5487    }
5488    llvm_unreachable("invalid BuiltinType::Kind value");
5489}
5490
5491static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
5492  EnumDecl *Enum = ET->getDecl();
5493
5494  // The encoding of an non-fixed enum type is always 'i', regardless of size.
5495  if (!Enum->isFixed())
5496    return 'i';
5497
5498  // The encoding of a fixed enum type matches its fixed underlying type.
5499  const BuiltinType *BT = Enum->getIntegerType()->castAs<BuiltinType>();
5500  return getObjCEncodingForPrimitiveKind(C, BT->getKind());
5501}
5502
5503static void EncodeBitField(const ASTContext *Ctx, std::string& S,
5504                           QualType T, const FieldDecl *FD) {
5505  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
5506  S += 'b';
5507  // The NeXT runtime encodes bit fields as b followed by the number of bits.
5508  // The GNU runtime requires more information; bitfields are encoded as b,
5509  // then the offset (in bits) of the first element, then the type of the
5510  // bitfield, then the size in bits.  For example, in this structure:
5511  //
5512  // struct
5513  // {
5514  //    int integer;
5515  //    int flags:2;
5516  // };
5517  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
5518  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
5519  // information is not especially sensible, but we're stuck with it for
5520  // compatibility with GCC, although providing it breaks anything that
5521  // actually uses runtime introspection and wants to work on both runtimes...
5522  if (Ctx->getLangOpts().ObjCRuntime.isGNUFamily()) {
5523    const RecordDecl *RD = FD->getParent();
5524    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
5525    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
5526    if (const EnumType *ET = T->getAs<EnumType>())
5527      S += ObjCEncodingForEnumType(Ctx, ET);
5528    else {
5529      const BuiltinType *BT = T->castAs<BuiltinType>();
5530      S += getObjCEncodingForPrimitiveKind(Ctx, BT->getKind());
5531    }
5532  }
5533  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
5534}
5535
5536// FIXME: Use SmallString for accumulating string.
5537void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
5538                                            bool ExpandPointedToStructures,
5539                                            bool ExpandStructures,
5540                                            const FieldDecl *FD,
5541                                            bool OutermostType,
5542                                            bool EncodingProperty,
5543                                            bool StructField,
5544                                            bool EncodeBlockParameters,
5545                                            bool EncodeClassNames,
5546                                            bool EncodePointerToObjCTypedef,
5547                                            QualType *NotEncodedT) const {
5548  CanQualType CT = getCanonicalType(T);
5549  switch (CT->getTypeClass()) {
5550  case Type::Builtin:
5551  case Type::Enum:
5552    if (FD && FD->isBitField())
5553      return EncodeBitField(this, S, T, FD);
5554    if (const BuiltinType *BT = dyn_cast<BuiltinType>(CT))
5555      S += getObjCEncodingForPrimitiveKind(this, BT->getKind());
5556    else
5557      S += ObjCEncodingForEnumType(this, cast<EnumType>(CT));
5558    return;
5559
5560  case Type::Complex: {
5561    const ComplexType *CT = T->castAs<ComplexType>();
5562    S += 'j';
5563    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, nullptr);
5564    return;
5565  }
5566
5567  case Type::Atomic: {
5568    const AtomicType *AT = T->castAs<AtomicType>();
5569    S += 'A';
5570    getObjCEncodingForTypeImpl(AT->getValueType(), S, false, false, nullptr);
5571    return;
5572  }
5573
5574  // encoding for pointer or reference types.
5575  case Type::Pointer:
5576  case Type::LValueReference:
5577  case Type::RValueReference: {
5578    QualType PointeeTy;
5579    if (isa<PointerType>(CT)) {
5580      const PointerType *PT = T->castAs<PointerType>();
5581      if (PT->isObjCSelType()) {
5582        S += ':';
5583        return;
5584      }
5585      PointeeTy = PT->getPointeeType();
5586    } else {
5587      PointeeTy = T->castAs<ReferenceType>()->getPointeeType();
5588    }
5589
5590    bool isReadOnly = false;
5591    // For historical/compatibility reasons, the read-only qualifier of the
5592    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
5593    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
5594    // Also, do not emit the 'r' for anything but the outermost type!
5595    if (isa<TypedefType>(T.getTypePtr())) {
5596      if (OutermostType && T.isConstQualified()) {
5597        isReadOnly = true;
5598        S += 'r';
5599      }
5600    } else if (OutermostType) {
5601      QualType P = PointeeTy;
5602      while (P->getAs<PointerType>())
5603        P = P->getAs<PointerType>()->getPointeeType();
5604      if (P.isConstQualified()) {
5605        isReadOnly = true;
5606        S += 'r';
5607      }
5608    }
5609    if (isReadOnly) {
5610      // Another legacy compatibility encoding. Some ObjC qualifier and type
5611      // combinations need to be rearranged.
5612      // Rewrite "in const" from "nr" to "rn"
5613      if (StringRef(S).endswith("nr"))
5614        S.replace(S.end()-2, S.end(), "rn");
5615    }
5616
5617    if (PointeeTy->isCharType()) {
5618      // char pointer types should be encoded as '*' unless it is a
5619      // type that has been typedef'd to 'BOOL'.
5620      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
5621        S += '*';
5622        return;
5623      }
5624    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
5625      // GCC binary compat: Need to convert "struct objc_class *" to "#".
5626      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
5627        S += '#';
5628        return;
5629      }
5630      // GCC binary compat: Need to convert "struct objc_object *" to "@".
5631      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
5632        S += '@';
5633        return;
5634      }
5635      // fall through...
5636    }
5637    S += '^';
5638    getLegacyIntegralTypeEncoding(PointeeTy);
5639
5640    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
5641                               nullptr, false, false, false, false, false, false,
5642                               NotEncodedT);
5643    return;
5644  }
5645
5646  case Type::ConstantArray:
5647  case Type::IncompleteArray:
5648  case Type::VariableArray: {
5649    const ArrayType *AT = cast<ArrayType>(CT);
5650
5651    if (isa<IncompleteArrayType>(AT) && !StructField) {
5652      // Incomplete arrays are encoded as a pointer to the array element.
5653      S += '^';
5654
5655      getObjCEncodingForTypeImpl(AT->getElementType(), S,
5656                                 false, ExpandStructures, FD);
5657    } else {
5658      S += '[';
5659
5660      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
5661        S += llvm::utostr(CAT->getSize().getZExtValue());
5662      else {
5663        //Variable length arrays are encoded as a regular array with 0 elements.
5664        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
5665               "Unknown array type!");
5666        S += '0';
5667      }
5668
5669      getObjCEncodingForTypeImpl(AT->getElementType(), S,
5670                                 false, ExpandStructures, FD,
5671                                 false, false, false, false, false, false,
5672                                 NotEncodedT);
5673      S += ']';
5674    }
5675    return;
5676  }
5677
5678  case Type::FunctionNoProto:
5679  case Type::FunctionProto:
5680    S += '?';
5681    return;
5682
5683  case Type::Record: {
5684    RecordDecl *RDecl = cast<RecordType>(CT)->getDecl();
5685    S += RDecl->isUnion() ? '(' : '{';
5686    // Anonymous structures print as '?'
5687    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
5688      S += II->getName();
5689      if (ClassTemplateSpecializationDecl *Spec
5690          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
5691        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
5692        llvm::raw_string_ostream OS(S);
5693        TemplateSpecializationType::PrintTemplateArgumentList(OS,
5694                                            TemplateArgs.data(),
5695                                            TemplateArgs.size(),
5696                                            (*this).getPrintingPolicy());
5697      }
5698    } else {
5699      S += '?';
5700    }
5701    if (ExpandStructures) {
5702      S += '=';
5703      if (!RDecl->isUnion()) {
5704        getObjCEncodingForStructureImpl(RDecl, S, FD, true, NotEncodedT);
5705      } else {
5706        for (const auto *Field : RDecl->fields()) {
5707          if (FD) {
5708            S += '"';
5709            S += Field->getNameAsString();
5710            S += '"';
5711          }
5712
5713          // Special case bit-fields.
5714          if (Field->isBitField()) {
5715            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
5716                                       Field);
5717          } else {
5718            QualType qt = Field->getType();
5719            getLegacyIntegralTypeEncoding(qt);
5720            getObjCEncodingForTypeImpl(qt, S, false, true,
5721                                       FD, /*OutermostType*/false,
5722                                       /*EncodingProperty*/false,
5723                                       /*StructField*/true,
5724                                       false, false, false, NotEncodedT);
5725          }
5726        }
5727      }
5728    }
5729    S += RDecl->isUnion() ? ')' : '}';
5730    return;
5731  }
5732
5733  case Type::BlockPointer: {
5734    const BlockPointerType *BT = T->castAs<BlockPointerType>();
5735    S += "@?"; // Unlike a pointer-to-function, which is "^?".
5736    if (EncodeBlockParameters) {
5737      const FunctionType *FT = BT->getPointeeType()->castAs<FunctionType>();
5738
5739      S += '<';
5740      // Block return type
5741      getObjCEncodingForTypeImpl(
5742          FT->getReturnType(), S, ExpandPointedToStructures, ExpandStructures,
5743          FD, false /* OutermostType */, EncodingProperty,
5744          false /* StructField */, EncodeBlockParameters, EncodeClassNames, false,
5745                                 NotEncodedT);
5746      // Block self
5747      S += "@?";
5748      // Block parameters
5749      if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT)) {
5750        for (const auto &I : FPT->param_types())
5751          getObjCEncodingForTypeImpl(
5752              I, S, ExpandPointedToStructures, ExpandStructures, FD,
5753              false /* OutermostType */, EncodingProperty,
5754              false /* StructField */, EncodeBlockParameters, EncodeClassNames,
5755                                     false, NotEncodedT);
5756      }
5757      S += '>';
5758    }
5759    return;
5760  }
5761
5762  case Type::ObjCObject: {
5763    // hack to match legacy encoding of *id and *Class
5764    QualType Ty = getObjCObjectPointerType(CT);
5765    if (Ty->isObjCIdType()) {
5766      S += "{objc_object=}";
5767      return;
5768    }
5769    else if (Ty->isObjCClassType()) {
5770      S += "{objc_class=}";
5771      return;
5772    }
5773  }
5774
5775  case Type::ObjCInterface: {
5776    // Ignore protocol qualifiers when mangling at this level.
5777    // @encode(class_name)
5778    ObjCInterfaceDecl *OI = T->castAs<ObjCObjectType>()->getInterface();
5779    S += '{';
5780    S += OI->getObjCRuntimeNameAsString();
5781    S += '=';
5782    SmallVector<const ObjCIvarDecl*, 32> Ivars;
5783    DeepCollectObjCIvars(OI, true, Ivars);
5784    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
5785      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
5786      if (Field->isBitField())
5787        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
5788      else
5789        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD,
5790                                   false, false, false, false, false,
5791                                   EncodePointerToObjCTypedef,
5792                                   NotEncodedT);
5793    }
5794    S += '}';
5795    return;
5796  }
5797
5798  case Type::ObjCObjectPointer: {
5799    const ObjCObjectPointerType *OPT = T->castAs<ObjCObjectPointerType>();
5800    if (OPT->isObjCIdType()) {
5801      S += '@';
5802      return;
5803    }
5804
5805    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
5806      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
5807      // Since this is a binary compatibility issue, need to consult with runtime
5808      // folks. Fortunately, this is a *very* obsure construct.
5809      S += '#';
5810      return;
5811    }
5812
5813    if (OPT->isObjCQualifiedIdType()) {
5814      getObjCEncodingForTypeImpl(getObjCIdType(), S,
5815                                 ExpandPointedToStructures,
5816                                 ExpandStructures, FD);
5817      if (FD || EncodingProperty || EncodeClassNames) {
5818        // Note that we do extended encoding of protocol qualifer list
5819        // Only when doing ivar or property encoding.
5820        S += '"';
5821        for (const auto *I : OPT->quals()) {
5822          S += '<';
5823          S += I->getObjCRuntimeNameAsString();
5824          S += '>';
5825        }
5826        S += '"';
5827      }
5828      return;
5829    }
5830
5831    QualType PointeeTy = OPT->getPointeeType();
5832    if (!EncodingProperty &&
5833        isa<TypedefType>(PointeeTy.getTypePtr()) &&
5834        !EncodePointerToObjCTypedef) {
5835      // Another historical/compatibility reason.
5836      // We encode the underlying type which comes out as
5837      // {...};
5838      S += '^';
5839      if (FD && OPT->getInterfaceDecl()) {
5840        // Prevent recursive encoding of fields in some rare cases.
5841        ObjCInterfaceDecl *OI = OPT->getInterfaceDecl();
5842        SmallVector<const ObjCIvarDecl*, 32> Ivars;
5843        DeepCollectObjCIvars(OI, true, Ivars);
5844        for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
5845          if (cast<FieldDecl>(Ivars[i]) == FD) {
5846            S += '{';
5847            S += OI->getObjCRuntimeNameAsString();
5848            S += '}';
5849            return;
5850          }
5851        }
5852      }
5853      getObjCEncodingForTypeImpl(PointeeTy, S,
5854                                 false, ExpandPointedToStructures,
5855                                 nullptr,
5856                                 false, false, false, false, false,
5857                                 /*EncodePointerToObjCTypedef*/true);
5858      return;
5859    }
5860
5861    S += '@';
5862    if (OPT->getInterfaceDecl() &&
5863        (FD || EncodingProperty || EncodeClassNames)) {
5864      S += '"';
5865      S += OPT->getInterfaceDecl()->getObjCRuntimeNameAsString();
5866      for (const auto *I : OPT->quals()) {
5867        S += '<';
5868        S += I->getObjCRuntimeNameAsString();
5869        S += '>';
5870      }
5871      S += '"';
5872    }
5873    return;
5874  }
5875
5876  // gcc just blithely ignores member pointers.
5877  // FIXME: we shoul do better than that.  'M' is available.
5878  case Type::MemberPointer:
5879  // This matches gcc's encoding, even though technically it is insufficient.
5880  //FIXME. We should do a better job than gcc.
5881  case Type::Vector:
5882  case Type::ExtVector:
5883  // Until we have a coherent encoding of these three types, issue warning.
5884    { if (NotEncodedT)
5885        *NotEncodedT = T;
5886      return;
5887    }
5888
5889  // We could see an undeduced auto type here during error recovery.
5890  // Just ignore it.
5891  case Type::Auto:
5892    return;
5893
5894  case Type::Pipe:
5895#define ABSTRACT_TYPE(KIND, BASE)
5896#define TYPE(KIND, BASE)
5897#define DEPENDENT_TYPE(KIND, BASE) \
5898  case Type::KIND:
5899#define NON_CANONICAL_TYPE(KIND, BASE) \
5900  case Type::KIND:
5901#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(KIND, BASE) \
5902  case Type::KIND:
5903#include "clang/AST/TypeNodes.def"
5904    llvm_unreachable("@encode for dependent type!");
5905  }
5906  llvm_unreachable("bad type kind!");
5907}
5908
5909void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
5910                                                 std::string &S,
5911                                                 const FieldDecl *FD,
5912                                                 bool includeVBases,
5913                                                 QualType *NotEncodedT) const {
5914  assert(RDecl && "Expected non-null RecordDecl");
5915  assert(!RDecl->isUnion() && "Should not be called for unions");
5916  if (!RDecl->getDefinition())
5917    return;
5918
5919  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
5920  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
5921  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
5922
5923  if (CXXRec) {
5924    for (const auto &BI : CXXRec->bases()) {
5925      if (!BI.isVirtual()) {
5926        CXXRecordDecl *base = BI.getType()->getAsCXXRecordDecl();
5927        if (base->isEmpty())
5928          continue;
5929        uint64_t offs = toBits(layout.getBaseClassOffset(base));
5930        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5931                                  std::make_pair(offs, base));
5932      }
5933    }
5934  }
5935
5936  unsigned i = 0;
5937  for (auto *Field : RDecl->fields()) {
5938    uint64_t offs = layout.getFieldOffset(i);
5939    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5940                              std::make_pair(offs, Field));
5941    ++i;
5942  }
5943
5944  if (CXXRec && includeVBases) {
5945    for (const auto &BI : CXXRec->vbases()) {
5946      CXXRecordDecl *base = BI.getType()->getAsCXXRecordDecl();
5947      if (base->isEmpty())
5948        continue;
5949      uint64_t offs = toBits(layout.getVBaseClassOffset(base));
5950      if (offs >= uint64_t(toBits(layout.getNonVirtualSize())) &&
5951          FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
5952        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
5953                                  std::make_pair(offs, base));
5954    }
5955  }
5956
5957  CharUnits size;
5958  if (CXXRec) {
5959    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
5960  } else {
5961    size = layout.getSize();
5962  }
5963
5964#ifndef NDEBUG
5965  uint64_t CurOffs = 0;
5966#endif
5967  std::multimap<uint64_t, NamedDecl *>::iterator
5968    CurLayObj = FieldOrBaseOffsets.begin();
5969
5970  if (CXXRec && CXXRec->isDynamicClass() &&
5971      (CurLayObj == FieldOrBaseOffsets.end() || CurLayObj->first != 0)) {
5972    if (FD) {
5973      S += "\"_vptr$";
5974      std::string recname = CXXRec->getNameAsString();
5975      if (recname.empty()) recname = "?";
5976      S += recname;
5977      S += '"';
5978    }
5979    S += "^^?";
5980#ifndef NDEBUG
5981    CurOffs += getTypeSize(VoidPtrTy);
5982#endif
5983  }
5984
5985  if (!RDecl->hasFlexibleArrayMember()) {
5986    // Mark the end of the structure.
5987    uint64_t offs = toBits(size);
5988    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5989                              std::make_pair(offs, nullptr));
5990  }
5991
5992  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
5993#ifndef NDEBUG
5994    assert(CurOffs <= CurLayObj->first);
5995    if (CurOffs < CurLayObj->first) {
5996      uint64_t padding = CurLayObj->first - CurOffs;
5997      // FIXME: There doesn't seem to be a way to indicate in the encoding that
5998      // packing/alignment of members is different that normal, in which case
5999      // the encoding will be out-of-sync with the real layout.
6000      // If the runtime switches to just consider the size of types without
6001      // taking into account alignment, we could make padding explicit in the
6002      // encoding (e.g. using arrays of chars). The encoding strings would be
6003      // longer then though.
6004      CurOffs += padding;
6005    }
6006#endif
6007
6008    NamedDecl *dcl = CurLayObj->second;
6009    if (!dcl)
6010      break; // reached end of structure.
6011
6012    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
6013      // We expand the bases without their virtual bases since those are going
6014      // in the initial structure. Note that this differs from gcc which
6015      // expands virtual bases each time one is encountered in the hierarchy,
6016      // making the encoding type bigger than it really is.
6017      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false,
6018                                      NotEncodedT);
6019      assert(!base->isEmpty());
6020#ifndef NDEBUG
6021      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
6022#endif
6023    } else {
6024      FieldDecl *field = cast<FieldDecl>(dcl);
6025      if (FD) {
6026        S += '"';
6027        S += field->getNameAsString();
6028        S += '"';
6029      }
6030
6031      if (field->isBitField()) {
6032        EncodeBitField(this, S, field->getType(), field);
6033#ifndef NDEBUG
6034        CurOffs += field->getBitWidthValue(*this);
6035#endif
6036      } else {
6037        QualType qt = field->getType();
6038        getLegacyIntegralTypeEncoding(qt);
6039        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
6040                                   /*OutermostType*/false,
6041                                   /*EncodingProperty*/false,
6042                                   /*StructField*/true,
6043                                   false, false, false, NotEncodedT);
6044#ifndef NDEBUG
6045        CurOffs += getTypeSize(field->getType());
6046#endif
6047      }
6048    }
6049  }
6050}
6051
6052void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
6053                                                 std::string& S) const {
6054  if (QT & Decl::OBJC_TQ_In)
6055    S += 'n';
6056  if (QT & Decl::OBJC_TQ_Inout)
6057    S += 'N';
6058  if (QT & Decl::OBJC_TQ_Out)
6059    S += 'o';
6060  if (QT & Decl::OBJC_TQ_Bycopy)
6061    S += 'O';
6062  if (QT & Decl::OBJC_TQ_Byref)
6063    S += 'R';
6064  if (QT & Decl::OBJC_TQ_Oneway)
6065    S += 'V';
6066}
6067
6068TypedefDecl *ASTContext::getObjCIdDecl() const {
6069  if (!ObjCIdDecl) {
6070    QualType T = getObjCObjectType(ObjCBuiltinIdTy, { }, { });
6071    T = getObjCObjectPointerType(T);
6072    ObjCIdDecl = buildImplicitTypedef(T, "id");
6073  }
6074  return ObjCIdDecl;
6075}
6076
6077TypedefDecl *ASTContext::getObjCSelDecl() const {
6078  if (!ObjCSelDecl) {
6079    QualType T = getPointerType(ObjCBuiltinSelTy);
6080    ObjCSelDecl = buildImplicitTypedef(T, "SEL");
6081  }
6082  return ObjCSelDecl;
6083}
6084
6085TypedefDecl *ASTContext::getObjCClassDecl() const {
6086  if (!ObjCClassDecl) {
6087    QualType T = getObjCObjectType(ObjCBuiltinClassTy, { }, { });
6088    T = getObjCObjectPointerType(T);
6089    ObjCClassDecl = buildImplicitTypedef(T, "Class");
6090  }
6091  return ObjCClassDecl;
6092}
6093
6094ObjCInterfaceDecl *ASTContext::getObjCProtocolDecl() const {
6095  if (!ObjCProtocolClassDecl) {
6096    ObjCProtocolClassDecl
6097      = ObjCInterfaceDecl::Create(*this, getTranslationUnitDecl(),
6098                                  SourceLocation(),
6099                                  &Idents.get("Protocol"),
6100                                  /*typeParamList=*/nullptr,
6101                                  /*PrevDecl=*/nullptr,
6102                                  SourceLocation(), true);
6103  }
6104
6105  return ObjCProtocolClassDecl;
6106}
6107
6108//===----------------------------------------------------------------------===//
6109// __builtin_va_list Construction Functions
6110//===----------------------------------------------------------------------===//
6111
6112static TypedefDecl *CreateCharPtrNamedVaListDecl(const ASTContext *Context,
6113                                                 StringRef Name) {
6114  // typedef char* __builtin[_ms]_va_list;
6115  QualType T = Context->getPointerType(Context->CharTy);
6116  return Context->buildImplicitTypedef(T, Name);
6117}
6118
6119static TypedefDecl *CreateMSVaListDecl(const ASTContext *Context) {
6120  return CreateCharPtrNamedVaListDecl(Context, "__builtin_ms_va_list");
6121}
6122
6123static TypedefDecl *CreateCharPtrBuiltinVaListDecl(const ASTContext *Context) {
6124  return CreateCharPtrNamedVaListDecl(Context, "__builtin_va_list");
6125}
6126
6127static TypedefDecl *CreateVoidPtrBuiltinVaListDecl(const ASTContext *Context) {
6128  // typedef void* __builtin_va_list;
6129  QualType T = Context->getPointerType(Context->VoidTy);
6130  return Context->buildImplicitTypedef(T, "__builtin_va_list");
6131}
6132
6133static TypedefDecl *
6134CreateAArch64ABIBuiltinVaListDecl(const ASTContext *Context) {
6135  // struct __va_list
6136  RecordDecl *VaListTagDecl = Context->buildImplicitRecord("__va_list");
6137  if (Context->getLangOpts().CPlusPlus) {
6138    // namespace std { struct __va_list {
6139    NamespaceDecl *NS;
6140    NS = NamespaceDecl::Create(const_cast<ASTContext &>(*Context),
6141                               Context->getTranslationUnitDecl(),
6142                               /*Inline*/ false, SourceLocation(),
6143                               SourceLocation(), &Context->Idents.get("std"),
6144                               /*PrevDecl*/ nullptr);
6145    NS->setImplicit();
6146    VaListTagDecl->setDeclContext(NS);
6147  }
6148
6149  VaListTagDecl->startDefinition();
6150
6151  const size_t NumFields = 5;
6152  QualType FieldTypes[NumFields];
6153  const char *FieldNames[NumFields];
6154
6155  // void *__stack;
6156  FieldTypes[0] = Context->getPointerType(Context->VoidTy);
6157  FieldNames[0] = "__stack";
6158
6159  // void *__gr_top;
6160  FieldTypes[1] = Context->getPointerType(Context->VoidTy);
6161  FieldNames[1] = "__gr_top";
6162
6163  // void *__vr_top;
6164  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
6165  FieldNames[2] = "__vr_top";
6166
6167  // int __gr_offs;
6168  FieldTypes[3] = Context->IntTy;
6169  FieldNames[3] = "__gr_offs";
6170
6171  // int __vr_offs;
6172  FieldTypes[4] = Context->IntTy;
6173  FieldNames[4] = "__vr_offs";
6174
6175  // Create fields
6176  for (unsigned i = 0; i < NumFields; ++i) {
6177    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6178                                         VaListTagDecl,
6179                                         SourceLocation(),
6180                                         SourceLocation(),
6181                                         &Context->Idents.get(FieldNames[i]),
6182                                         FieldTypes[i], /*TInfo=*/nullptr,
6183                                         /*BitWidth=*/nullptr,
6184                                         /*Mutable=*/false,
6185                                         ICIS_NoInit);
6186    Field->setAccess(AS_public);
6187    VaListTagDecl->addDecl(Field);
6188  }
6189  VaListTagDecl->completeDefinition();
6190  Context->VaListTagDecl = VaListTagDecl;
6191  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
6192
6193  // } __builtin_va_list;
6194  return Context->buildImplicitTypedef(VaListTagType, "__builtin_va_list");
6195}
6196
6197static TypedefDecl *CreatePowerABIBuiltinVaListDecl(const ASTContext *Context) {
6198  // typedef struct __va_list_tag {
6199  RecordDecl *VaListTagDecl;
6200
6201  VaListTagDecl = Context->buildImplicitRecord("__va_list_tag");
6202  VaListTagDecl->startDefinition();
6203
6204  const size_t NumFields = 5;
6205  QualType FieldTypes[NumFields];
6206  const char *FieldNames[NumFields];
6207
6208  //   unsigned char gpr;
6209  FieldTypes[0] = Context->UnsignedCharTy;
6210  FieldNames[0] = "gpr";
6211
6212  //   unsigned char fpr;
6213  FieldTypes[1] = Context->UnsignedCharTy;
6214  FieldNames[1] = "fpr";
6215
6216  //   unsigned short reserved;
6217  FieldTypes[2] = Context->UnsignedShortTy;
6218  FieldNames[2] = "reserved";
6219
6220  //   void* overflow_arg_area;
6221  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
6222  FieldNames[3] = "overflow_arg_area";
6223
6224  //   void* reg_save_area;
6225  FieldTypes[4] = Context->getPointerType(Context->VoidTy);
6226  FieldNames[4] = "reg_save_area";
6227
6228  // Create fields
6229  for (unsigned i = 0; i < NumFields; ++i) {
6230    FieldDecl *Field = FieldDecl::Create(*Context, VaListTagDecl,
6231                                         SourceLocation(),
6232                                         SourceLocation(),
6233                                         &Context->Idents.get(FieldNames[i]),
6234                                         FieldTypes[i], /*TInfo=*/nullptr,
6235                                         /*BitWidth=*/nullptr,
6236                                         /*Mutable=*/false,
6237                                         ICIS_NoInit);
6238    Field->setAccess(AS_public);
6239    VaListTagDecl->addDecl(Field);
6240  }
6241  VaListTagDecl->completeDefinition();
6242  Context->VaListTagDecl = VaListTagDecl;
6243  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
6244
6245  // } __va_list_tag;
6246  TypedefDecl *VaListTagTypedefDecl =
6247      Context->buildImplicitTypedef(VaListTagType, "__va_list_tag");
6248
6249  QualType VaListTagTypedefType =
6250    Context->getTypedefType(VaListTagTypedefDecl);
6251
6252  // typedef __va_list_tag __builtin_va_list[1];
6253  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
6254  QualType VaListTagArrayType
6255    = Context->getConstantArrayType(VaListTagTypedefType,
6256                                    Size, ArrayType::Normal, 0);
6257  return Context->buildImplicitTypedef(VaListTagArrayType, "__builtin_va_list");
6258}
6259
6260static TypedefDecl *
6261CreateX86_64ABIBuiltinVaListDecl(const ASTContext *Context) {
6262  // struct __va_list_tag {
6263  RecordDecl *VaListTagDecl;
6264  VaListTagDecl = Context->buildImplicitRecord("__va_list_tag");
6265  VaListTagDecl->startDefinition();
6266
6267  const size_t NumFields = 4;
6268  QualType FieldTypes[NumFields];
6269  const char *FieldNames[NumFields];
6270
6271  //   unsigned gp_offset;
6272  FieldTypes[0] = Context->UnsignedIntTy;
6273  FieldNames[0] = "gp_offset";
6274
6275  //   unsigned fp_offset;
6276  FieldTypes[1] = Context->UnsignedIntTy;
6277  FieldNames[1] = "fp_offset";
6278
6279  //   void* overflow_arg_area;
6280  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
6281  FieldNames[2] = "overflow_arg_area";
6282
6283  //   void* reg_save_area;
6284  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
6285  FieldNames[3] = "reg_save_area";
6286
6287  // Create fields
6288  for (unsigned i = 0; i < NumFields; ++i) {
6289    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6290                                         VaListTagDecl,
6291                                         SourceLocation(),
6292                                         SourceLocation(),
6293                                         &Context->Idents.get(FieldNames[i]),
6294                                         FieldTypes[i], /*TInfo=*/nullptr,
6295                                         /*BitWidth=*/nullptr,
6296                                         /*Mutable=*/false,
6297                                         ICIS_NoInit);
6298    Field->setAccess(AS_public);
6299    VaListTagDecl->addDecl(Field);
6300  }
6301  VaListTagDecl->completeDefinition();
6302  Context->VaListTagDecl = VaListTagDecl;
6303  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
6304
6305  // };
6306
6307  // typedef struct __va_list_tag __builtin_va_list[1];
6308  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
6309  QualType VaListTagArrayType =
6310      Context->getConstantArrayType(VaListTagType, Size, ArrayType::Normal, 0);
6311  return Context->buildImplicitTypedef(VaListTagArrayType, "__builtin_va_list");
6312}
6313
6314static TypedefDecl *CreatePNaClABIBuiltinVaListDecl(const ASTContext *Context) {
6315  // typedef int __builtin_va_list[4];
6316  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 4);
6317  QualType IntArrayType
6318    = Context->getConstantArrayType(Context->IntTy,
6319				    Size, ArrayType::Normal, 0);
6320  return Context->buildImplicitTypedef(IntArrayType, "__builtin_va_list");
6321}
6322
6323static TypedefDecl *
6324CreateAAPCSABIBuiltinVaListDecl(const ASTContext *Context) {
6325  // struct __va_list
6326  RecordDecl *VaListDecl = Context->buildImplicitRecord("__va_list");
6327  if (Context->getLangOpts().CPlusPlus) {
6328    // namespace std { struct __va_list {
6329    NamespaceDecl *NS;
6330    NS = NamespaceDecl::Create(const_cast<ASTContext &>(*Context),
6331                               Context->getTranslationUnitDecl(),
6332                               /*Inline*/false, SourceLocation(),
6333                               SourceLocation(), &Context->Idents.get("std"),
6334                               /*PrevDecl*/ nullptr);
6335    NS->setImplicit();
6336    VaListDecl->setDeclContext(NS);
6337  }
6338
6339  VaListDecl->startDefinition();
6340
6341  // void * __ap;
6342  FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6343                                       VaListDecl,
6344                                       SourceLocation(),
6345                                       SourceLocation(),
6346                                       &Context->Idents.get("__ap"),
6347                                       Context->getPointerType(Context->VoidTy),
6348                                       /*TInfo=*/nullptr,
6349                                       /*BitWidth=*/nullptr,
6350                                       /*Mutable=*/false,
6351                                       ICIS_NoInit);
6352  Field->setAccess(AS_public);
6353  VaListDecl->addDecl(Field);
6354
6355  // };
6356  VaListDecl->completeDefinition();
6357
6358  // typedef struct __va_list __builtin_va_list;
6359  QualType T = Context->getRecordType(VaListDecl);
6360  return Context->buildImplicitTypedef(T, "__builtin_va_list");
6361}
6362
6363static TypedefDecl *
6364CreateSystemZBuiltinVaListDecl(const ASTContext *Context) {
6365  // struct __va_list_tag {
6366  RecordDecl *VaListTagDecl;
6367  VaListTagDecl = Context->buildImplicitRecord("__va_list_tag");
6368  VaListTagDecl->startDefinition();
6369
6370  const size_t NumFields = 4;
6371  QualType FieldTypes[NumFields];
6372  const char *FieldNames[NumFields];
6373
6374  //   long __gpr;
6375  FieldTypes[0] = Context->LongTy;
6376  FieldNames[0] = "__gpr";
6377
6378  //   long __fpr;
6379  FieldTypes[1] = Context->LongTy;
6380  FieldNames[1] = "__fpr";
6381
6382  //   void *__overflow_arg_area;
6383  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
6384  FieldNames[2] = "__overflow_arg_area";
6385
6386  //   void *__reg_save_area;
6387  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
6388  FieldNames[3] = "__reg_save_area";
6389
6390  // Create fields
6391  for (unsigned i = 0; i < NumFields; ++i) {
6392    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6393                                         VaListTagDecl,
6394                                         SourceLocation(),
6395                                         SourceLocation(),
6396                                         &Context->Idents.get(FieldNames[i]),
6397                                         FieldTypes[i], /*TInfo=*/nullptr,
6398                                         /*BitWidth=*/nullptr,
6399                                         /*Mutable=*/false,
6400                                         ICIS_NoInit);
6401    Field->setAccess(AS_public);
6402    VaListTagDecl->addDecl(Field);
6403  }
6404  VaListTagDecl->completeDefinition();
6405  Context->VaListTagDecl = VaListTagDecl;
6406  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
6407
6408  // };
6409
6410  // typedef __va_list_tag __builtin_va_list[1];
6411  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
6412  QualType VaListTagArrayType =
6413      Context->getConstantArrayType(VaListTagType, Size, ArrayType::Normal, 0);
6414
6415  return Context->buildImplicitTypedef(VaListTagArrayType, "__builtin_va_list");
6416}
6417
6418static TypedefDecl *CreateVaListDecl(const ASTContext *Context,
6419                                     TargetInfo::BuiltinVaListKind Kind) {
6420  switch (Kind) {
6421  case TargetInfo::CharPtrBuiltinVaList:
6422    return CreateCharPtrBuiltinVaListDecl(Context);
6423  case TargetInfo::VoidPtrBuiltinVaList:
6424    return CreateVoidPtrBuiltinVaListDecl(Context);
6425  case TargetInfo::AArch64ABIBuiltinVaList:
6426    return CreateAArch64ABIBuiltinVaListDecl(Context);
6427  case TargetInfo::PowerABIBuiltinVaList:
6428    return CreatePowerABIBuiltinVaListDecl(Context);
6429  case TargetInfo::X86_64ABIBuiltinVaList:
6430    return CreateX86_64ABIBuiltinVaListDecl(Context);
6431  case TargetInfo::PNaClABIBuiltinVaList:
6432    return CreatePNaClABIBuiltinVaListDecl(Context);
6433  case TargetInfo::AAPCSABIBuiltinVaList:
6434    return CreateAAPCSABIBuiltinVaListDecl(Context);
6435  case TargetInfo::SystemZBuiltinVaList:
6436    return CreateSystemZBuiltinVaListDecl(Context);
6437  }
6438
6439  llvm_unreachable("Unhandled __builtin_va_list type kind");
6440}
6441
6442TypedefDecl *ASTContext::getBuiltinVaListDecl() const {
6443  if (!BuiltinVaListDecl) {
6444    BuiltinVaListDecl = CreateVaListDecl(this, Target->getBuiltinVaListKind());
6445    assert(BuiltinVaListDecl->isImplicit());
6446  }
6447
6448  return BuiltinVaListDecl;
6449}
6450
6451Decl *ASTContext::getVaListTagDecl() const {
6452  // Force the creation of VaListTagDecl by building the __builtin_va_list
6453  // declaration.
6454  if (!VaListTagDecl)
6455    (void)getBuiltinVaListDecl();
6456
6457  return VaListTagDecl;
6458}
6459
6460TypedefDecl *ASTContext::getBuiltinMSVaListDecl() const {
6461  if (!BuiltinMSVaListDecl)
6462    BuiltinMSVaListDecl = CreateMSVaListDecl(this);
6463
6464  return BuiltinMSVaListDecl;
6465}
6466
6467void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
6468  assert(ObjCConstantStringType.isNull() &&
6469         "'NSConstantString' type already set!");
6470
6471  ObjCConstantStringType = getObjCInterfaceType(Decl);
6472}
6473
6474/// \brief Retrieve the template name that corresponds to a non-empty
6475/// lookup.
6476TemplateName
6477ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
6478                                      UnresolvedSetIterator End) const {
6479  unsigned size = End - Begin;
6480  assert(size > 1 && "set is not overloaded!");
6481
6482  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
6483                          size * sizeof(FunctionTemplateDecl*));
6484  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
6485
6486  NamedDecl **Storage = OT->getStorage();
6487  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
6488    NamedDecl *D = *I;
6489    assert(isa<FunctionTemplateDecl>(D) ||
6490           (isa<UsingShadowDecl>(D) &&
6491            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
6492    *Storage++ = D;
6493  }
6494
6495  return TemplateName(OT);
6496}
6497
6498/// \brief Retrieve the template name that represents a qualified
6499/// template name such as \c std::vector.
6500TemplateName
6501ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
6502                                     bool TemplateKeyword,
6503                                     TemplateDecl *Template) const {
6504  assert(NNS && "Missing nested-name-specifier in qualified template name");
6505
6506  // FIXME: Canonicalization?
6507  llvm::FoldingSetNodeID ID;
6508  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
6509
6510  void *InsertPos = nullptr;
6511  QualifiedTemplateName *QTN =
6512    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6513  if (!QTN) {
6514    QTN = new (*this, llvm::alignOf<QualifiedTemplateName>())
6515        QualifiedTemplateName(NNS, TemplateKeyword, Template);
6516    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
6517  }
6518
6519  return TemplateName(QTN);
6520}
6521
6522/// \brief Retrieve the template name that represents a dependent
6523/// template name such as \c MetaFun::template apply.
6524TemplateName
6525ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
6526                                     const IdentifierInfo *Name) const {
6527  assert((!NNS || NNS->isDependent()) &&
6528         "Nested name specifier must be dependent");
6529
6530  llvm::FoldingSetNodeID ID;
6531  DependentTemplateName::Profile(ID, NNS, Name);
6532
6533  void *InsertPos = nullptr;
6534  DependentTemplateName *QTN =
6535    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6536
6537  if (QTN)
6538    return TemplateName(QTN);
6539
6540  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
6541  if (CanonNNS == NNS) {
6542    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6543        DependentTemplateName(NNS, Name);
6544  } else {
6545    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
6546    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6547        DependentTemplateName(NNS, Name, Canon);
6548    DependentTemplateName *CheckQTN =
6549      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6550    assert(!CheckQTN && "Dependent type name canonicalization broken");
6551    (void)CheckQTN;
6552  }
6553
6554  DependentTemplateNames.InsertNode(QTN, InsertPos);
6555  return TemplateName(QTN);
6556}
6557
6558/// \brief Retrieve the template name that represents a dependent
6559/// template name such as \c MetaFun::template operator+.
6560TemplateName
6561ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
6562                                     OverloadedOperatorKind Operator) const {
6563  assert((!NNS || NNS->isDependent()) &&
6564         "Nested name specifier must be dependent");
6565
6566  llvm::FoldingSetNodeID ID;
6567  DependentTemplateName::Profile(ID, NNS, Operator);
6568
6569  void *InsertPos = nullptr;
6570  DependentTemplateName *QTN
6571    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6572
6573  if (QTN)
6574    return TemplateName(QTN);
6575
6576  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
6577  if (CanonNNS == NNS) {
6578    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6579        DependentTemplateName(NNS, Operator);
6580  } else {
6581    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
6582    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6583        DependentTemplateName(NNS, Operator, Canon);
6584
6585    DependentTemplateName *CheckQTN
6586      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6587    assert(!CheckQTN && "Dependent template name canonicalization broken");
6588    (void)CheckQTN;
6589  }
6590
6591  DependentTemplateNames.InsertNode(QTN, InsertPos);
6592  return TemplateName(QTN);
6593}
6594
6595TemplateName
6596ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
6597                                         TemplateName replacement) const {
6598  llvm::FoldingSetNodeID ID;
6599  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
6600
6601  void *insertPos = nullptr;
6602  SubstTemplateTemplateParmStorage *subst
6603    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
6604
6605  if (!subst) {
6606    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
6607    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
6608  }
6609
6610  return TemplateName(subst);
6611}
6612
6613TemplateName
6614ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
6615                                       const TemplateArgument &ArgPack) const {
6616  ASTContext &Self = const_cast<ASTContext &>(*this);
6617  llvm::FoldingSetNodeID ID;
6618  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
6619
6620  void *InsertPos = nullptr;
6621  SubstTemplateTemplateParmPackStorage *Subst
6622    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
6623
6624  if (!Subst) {
6625    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
6626                                                           ArgPack.pack_size(),
6627                                                         ArgPack.pack_begin());
6628    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
6629  }
6630
6631  return TemplateName(Subst);
6632}
6633
6634/// getFromTargetType - Given one of the integer types provided by
6635/// TargetInfo, produce the corresponding type. The unsigned @p Type
6636/// is actually a value of type @c TargetInfo::IntType.
6637CanQualType ASTContext::getFromTargetType(unsigned Type) const {
6638  switch (Type) {
6639  case TargetInfo::NoInt: return CanQualType();
6640  case TargetInfo::SignedChar: return SignedCharTy;
6641  case TargetInfo::UnsignedChar: return UnsignedCharTy;
6642  case TargetInfo::SignedShort: return ShortTy;
6643  case TargetInfo::UnsignedShort: return UnsignedShortTy;
6644  case TargetInfo::SignedInt: return IntTy;
6645  case TargetInfo::UnsignedInt: return UnsignedIntTy;
6646  case TargetInfo::SignedLong: return LongTy;
6647  case TargetInfo::UnsignedLong: return UnsignedLongTy;
6648  case TargetInfo::SignedLongLong: return LongLongTy;
6649  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
6650  }
6651
6652  llvm_unreachable("Unhandled TargetInfo::IntType value");
6653}
6654
6655//===----------------------------------------------------------------------===//
6656//                        Type Predicates.
6657//===----------------------------------------------------------------------===//
6658
6659/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
6660/// garbage collection attribute.
6661///
6662Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
6663  if (getLangOpts().getGC() == LangOptions::NonGC)
6664    return Qualifiers::GCNone;
6665
6666  assert(getLangOpts().ObjC1);
6667  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
6668
6669  // Default behaviour under objective-C's gc is for ObjC pointers
6670  // (or pointers to them) be treated as though they were declared
6671  // as __strong.
6672  if (GCAttrs == Qualifiers::GCNone) {
6673    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
6674      return Qualifiers::Strong;
6675    else if (Ty->isPointerType())
6676      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
6677  } else {
6678    // It's not valid to set GC attributes on anything that isn't a
6679    // pointer.
6680#ifndef NDEBUG
6681    QualType CT = Ty->getCanonicalTypeInternal();
6682    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
6683      CT = AT->getElementType();
6684    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
6685#endif
6686  }
6687  return GCAttrs;
6688}
6689
6690//===----------------------------------------------------------------------===//
6691//                        Type Compatibility Testing
6692//===----------------------------------------------------------------------===//
6693
6694/// areCompatVectorTypes - Return true if the two specified vector types are
6695/// compatible.
6696static bool areCompatVectorTypes(const VectorType *LHS,
6697                                 const VectorType *RHS) {
6698  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
6699  return LHS->getElementType() == RHS->getElementType() &&
6700         LHS->getNumElements() == RHS->getNumElements();
6701}
6702
6703bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
6704                                          QualType SecondVec) {
6705  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
6706  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
6707
6708  if (hasSameUnqualifiedType(FirstVec, SecondVec))
6709    return true;
6710
6711  // Treat Neon vector types and most AltiVec vector types as if they are the
6712  // equivalent GCC vector types.
6713  const VectorType *First = FirstVec->getAs<VectorType>();
6714  const VectorType *Second = SecondVec->getAs<VectorType>();
6715  if (First->getNumElements() == Second->getNumElements() &&
6716      hasSameType(First->getElementType(), Second->getElementType()) &&
6717      First->getVectorKind() != VectorType::AltiVecPixel &&
6718      First->getVectorKind() != VectorType::AltiVecBool &&
6719      Second->getVectorKind() != VectorType::AltiVecPixel &&
6720      Second->getVectorKind() != VectorType::AltiVecBool)
6721    return true;
6722
6723  return false;
6724}
6725
6726//===----------------------------------------------------------------------===//
6727// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
6728//===----------------------------------------------------------------------===//
6729
6730/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
6731/// inheritance hierarchy of 'rProto'.
6732bool
6733ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
6734                                           ObjCProtocolDecl *rProto) const {
6735  if (declaresSameEntity(lProto, rProto))
6736    return true;
6737  for (auto *PI : rProto->protocols())
6738    if (ProtocolCompatibleWithProtocol(lProto, PI))
6739      return true;
6740  return false;
6741}
6742
6743/// ObjCQualifiedClassTypesAreCompatible - compare  Class<pr,...> and
6744/// Class<pr1, ...>.
6745bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
6746                                                      QualType rhs) {
6747  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
6748  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
6749  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
6750
6751  for (auto *lhsProto : lhsQID->quals()) {
6752    bool match = false;
6753    for (auto *rhsProto : rhsOPT->quals()) {
6754      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
6755        match = true;
6756        break;
6757      }
6758    }
6759    if (!match)
6760      return false;
6761  }
6762  return true;
6763}
6764
6765/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
6766/// ObjCQualifiedIDType.
6767bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
6768                                                   bool compare) {
6769  // Allow id<P..> and an 'id' or void* type in all cases.
6770  if (lhs->isVoidPointerType() ||
6771      lhs->isObjCIdType() || lhs->isObjCClassType())
6772    return true;
6773  else if (rhs->isVoidPointerType() ||
6774           rhs->isObjCIdType() || rhs->isObjCClassType())
6775    return true;
6776
6777  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
6778    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
6779
6780    if (!rhsOPT) return false;
6781
6782    if (rhsOPT->qual_empty()) {
6783      // If the RHS is a unqualified interface pointer "NSString*",
6784      // make sure we check the class hierarchy.
6785      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
6786        for (auto *I : lhsQID->quals()) {
6787          // when comparing an id<P> on lhs with a static type on rhs,
6788          // see if static class implements all of id's protocols, directly or
6789          // through its super class and categories.
6790          if (!rhsID->ClassImplementsProtocol(I, true))
6791            return false;
6792        }
6793      }
6794      // If there are no qualifiers and no interface, we have an 'id'.
6795      return true;
6796    }
6797    // Both the right and left sides have qualifiers.
6798    for (auto *lhsProto : lhsQID->quals()) {
6799      bool match = false;
6800
6801      // when comparing an id<P> on lhs with a static type on rhs,
6802      // see if static class implements all of id's protocols, directly or
6803      // through its super class and categories.
6804      for (auto *rhsProto : rhsOPT->quals()) {
6805        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6806            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6807          match = true;
6808          break;
6809        }
6810      }
6811      // If the RHS is a qualified interface pointer "NSString<P>*",
6812      // make sure we check the class hierarchy.
6813      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
6814        for (auto *I : lhsQID->quals()) {
6815          // when comparing an id<P> on lhs with a static type on rhs,
6816          // see if static class implements all of id's protocols, directly or
6817          // through its super class and categories.
6818          if (rhsID->ClassImplementsProtocol(I, true)) {
6819            match = true;
6820            break;
6821          }
6822        }
6823      }
6824      if (!match)
6825        return false;
6826    }
6827
6828    return true;
6829  }
6830
6831  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
6832  assert(rhsQID && "One of the LHS/RHS should be id<x>");
6833
6834  if (const ObjCObjectPointerType *lhsOPT =
6835        lhs->getAsObjCInterfacePointerType()) {
6836    // If both the right and left sides have qualifiers.
6837    for (auto *lhsProto : lhsOPT->quals()) {
6838      bool match = false;
6839
6840      // when comparing an id<P> on rhs with a static type on lhs,
6841      // see if static class implements all of id's protocols, directly or
6842      // through its super class and categories.
6843      // First, lhs protocols in the qualifier list must be found, direct
6844      // or indirect in rhs's qualifier list or it is a mismatch.
6845      for (auto *rhsProto : rhsQID->quals()) {
6846        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6847            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6848          match = true;
6849          break;
6850        }
6851      }
6852      if (!match)
6853        return false;
6854    }
6855
6856    // Static class's protocols, or its super class or category protocols
6857    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
6858    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
6859      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
6860      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
6861      // This is rather dubious but matches gcc's behavior. If lhs has
6862      // no type qualifier and its class has no static protocol(s)
6863      // assume that it is mismatch.
6864      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
6865        return false;
6866      for (auto *lhsProto : LHSInheritedProtocols) {
6867        bool match = false;
6868        for (auto *rhsProto : rhsQID->quals()) {
6869          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6870              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6871            match = true;
6872            break;
6873          }
6874        }
6875        if (!match)
6876          return false;
6877      }
6878    }
6879    return true;
6880  }
6881  return false;
6882}
6883
6884/// canAssignObjCInterfaces - Return true if the two interface types are
6885/// compatible for assignment from RHS to LHS.  This handles validation of any
6886/// protocol qualifiers on the LHS or RHS.
6887///
6888bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
6889                                         const ObjCObjectPointerType *RHSOPT) {
6890  const ObjCObjectType* LHS = LHSOPT->getObjectType();
6891  const ObjCObjectType* RHS = RHSOPT->getObjectType();
6892
6893  // If either type represents the built-in 'id' or 'Class' types, return true.
6894  if (LHS->isObjCUnqualifiedIdOrClass() ||
6895      RHS->isObjCUnqualifiedIdOrClass())
6896    return true;
6897
6898  // Function object that propagates a successful result or handles
6899  // __kindof types.
6900  auto finish = [&](bool succeeded) -> bool {
6901    if (succeeded)
6902      return true;
6903
6904    if (!RHS->isKindOfType())
6905      return false;
6906
6907    // Strip off __kindof and protocol qualifiers, then check whether
6908    // we can assign the other way.
6909    return canAssignObjCInterfaces(RHSOPT->stripObjCKindOfTypeAndQuals(*this),
6910                                   LHSOPT->stripObjCKindOfTypeAndQuals(*this));
6911  };
6912
6913  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId()) {
6914    return finish(ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
6915                                                    QualType(RHSOPT,0),
6916                                                    false));
6917  }
6918
6919  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass()) {
6920    return finish(ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
6921                                                       QualType(RHSOPT,0)));
6922  }
6923
6924  // If we have 2 user-defined types, fall into that path.
6925  if (LHS->getInterface() && RHS->getInterface()) {
6926    return finish(canAssignObjCInterfaces(LHS, RHS));
6927  }
6928
6929  return false;
6930}
6931
6932/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
6933/// for providing type-safety for objective-c pointers used to pass/return
6934/// arguments in block literals. When passed as arguments, passing 'A*' where
6935/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
6936/// not OK. For the return type, the opposite is not OK.
6937bool ASTContext::canAssignObjCInterfacesInBlockPointer(
6938                                         const ObjCObjectPointerType *LHSOPT,
6939                                         const ObjCObjectPointerType *RHSOPT,
6940                                         bool BlockReturnType) {
6941
6942  // Function object that propagates a successful result or handles
6943  // __kindof types.
6944  auto finish = [&](bool succeeded) -> bool {
6945    if (succeeded)
6946      return true;
6947
6948    const ObjCObjectPointerType *Expected = BlockReturnType ? RHSOPT : LHSOPT;
6949    if (!Expected->isKindOfType())
6950      return false;
6951
6952    // Strip off __kindof and protocol qualifiers, then check whether
6953    // we can assign the other way.
6954    return canAssignObjCInterfacesInBlockPointer(
6955             RHSOPT->stripObjCKindOfTypeAndQuals(*this),
6956             LHSOPT->stripObjCKindOfTypeAndQuals(*this),
6957             BlockReturnType);
6958  };
6959
6960  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
6961    return true;
6962
6963  if (LHSOPT->isObjCBuiltinType()) {
6964    return finish(RHSOPT->isObjCBuiltinType() ||
6965                  RHSOPT->isObjCQualifiedIdType());
6966  }
6967
6968  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
6969    return finish(ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
6970                                                    QualType(RHSOPT,0),
6971                                                    false));
6972
6973  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
6974  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
6975  if (LHS && RHS)  { // We have 2 user-defined types.
6976    if (LHS != RHS) {
6977      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
6978        return finish(BlockReturnType);
6979      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
6980        return finish(!BlockReturnType);
6981    }
6982    else
6983      return true;
6984  }
6985  return false;
6986}
6987
6988/// Comparison routine for Objective-C protocols to be used with
6989/// llvm::array_pod_sort.
6990static int compareObjCProtocolsByName(ObjCProtocolDecl * const *lhs,
6991                                      ObjCProtocolDecl * const *rhs) {
6992  return (*lhs)->getName().compare((*rhs)->getName());
6993
6994}
6995
6996/// getIntersectionOfProtocols - This routine finds the intersection of set
6997/// of protocols inherited from two distinct objective-c pointer objects with
6998/// the given common base.
6999/// It is used to build composite qualifier list of the composite type of
7000/// the conditional expression involving two objective-c pointer objects.
7001static
7002void getIntersectionOfProtocols(ASTContext &Context,
7003                                const ObjCInterfaceDecl *CommonBase,
7004                                const ObjCObjectPointerType *LHSOPT,
7005                                const ObjCObjectPointerType *RHSOPT,
7006      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionSet) {
7007
7008  const ObjCObjectType* LHS = LHSOPT->getObjectType();
7009  const ObjCObjectType* RHS = RHSOPT->getObjectType();
7010  assert(LHS->getInterface() && "LHS must have an interface base");
7011  assert(RHS->getInterface() && "RHS must have an interface base");
7012
7013  // Add all of the protocols for the LHS.
7014  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSProtocolSet;
7015
7016  // Start with the protocol qualifiers.
7017  for (auto proto : LHS->quals()) {
7018    Context.CollectInheritedProtocols(proto, LHSProtocolSet);
7019  }
7020
7021  // Also add the protocols associated with the LHS interface.
7022  Context.CollectInheritedProtocols(LHS->getInterface(), LHSProtocolSet);
7023
7024  // Add all of the protocls for the RHS.
7025  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSProtocolSet;
7026
7027  // Start with the protocol qualifiers.
7028  for (auto proto : RHS->quals()) {
7029    Context.CollectInheritedProtocols(proto, RHSProtocolSet);
7030  }
7031
7032  // Also add the protocols associated with the RHS interface.
7033  Context.CollectInheritedProtocols(RHS->getInterface(), RHSProtocolSet);
7034
7035  // Compute the intersection of the collected protocol sets.
7036  for (auto proto : LHSProtocolSet) {
7037    if (RHSProtocolSet.count(proto))
7038      IntersectionSet.push_back(proto);
7039  }
7040
7041  // Compute the set of protocols that is implied by either the common type or
7042  // the protocols within the intersection.
7043  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> ImpliedProtocols;
7044  Context.CollectInheritedProtocols(CommonBase, ImpliedProtocols);
7045
7046  // Remove any implied protocols from the list of inherited protocols.
7047  if (!ImpliedProtocols.empty()) {
7048    IntersectionSet.erase(
7049      std::remove_if(IntersectionSet.begin(),
7050                     IntersectionSet.end(),
7051                     [&](ObjCProtocolDecl *proto) -> bool {
7052                       return ImpliedProtocols.count(proto) > 0;
7053                     }),
7054      IntersectionSet.end());
7055  }
7056
7057  // Sort the remaining protocols by name.
7058  llvm::array_pod_sort(IntersectionSet.begin(), IntersectionSet.end(),
7059                       compareObjCProtocolsByName);
7060}
7061
7062/// Determine whether the first type is a subtype of the second.
7063static bool canAssignObjCObjectTypes(ASTContext &ctx, QualType lhs,
7064                                     QualType rhs) {
7065  // Common case: two object pointers.
7066  const ObjCObjectPointerType *lhsOPT = lhs->getAs<ObjCObjectPointerType>();
7067  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
7068  if (lhsOPT && rhsOPT)
7069    return ctx.canAssignObjCInterfaces(lhsOPT, rhsOPT);
7070
7071  // Two block pointers.
7072  const BlockPointerType *lhsBlock = lhs->getAs<BlockPointerType>();
7073  const BlockPointerType *rhsBlock = rhs->getAs<BlockPointerType>();
7074  if (lhsBlock && rhsBlock)
7075    return ctx.typesAreBlockPointerCompatible(lhs, rhs);
7076
7077  // If either is an unqualified 'id' and the other is a block, it's
7078  // acceptable.
7079  if ((lhsOPT && lhsOPT->isObjCIdType() && rhsBlock) ||
7080      (rhsOPT && rhsOPT->isObjCIdType() && lhsBlock))
7081    return true;
7082
7083  return false;
7084}
7085
7086// Check that the given Objective-C type argument lists are equivalent.
7087static bool sameObjCTypeArgs(ASTContext &ctx,
7088                             const ObjCInterfaceDecl *iface,
7089                             ArrayRef<QualType> lhsArgs,
7090                             ArrayRef<QualType> rhsArgs,
7091                             bool stripKindOf) {
7092  if (lhsArgs.size() != rhsArgs.size())
7093    return false;
7094
7095  ObjCTypeParamList *typeParams = iface->getTypeParamList();
7096  for (unsigned i = 0, n = lhsArgs.size(); i != n; ++i) {
7097    if (ctx.hasSameType(lhsArgs[i], rhsArgs[i]))
7098      continue;
7099
7100    switch (typeParams->begin()[i]->getVariance()) {
7101    case ObjCTypeParamVariance::Invariant:
7102      if (!stripKindOf ||
7103          !ctx.hasSameType(lhsArgs[i].stripObjCKindOfType(ctx),
7104                           rhsArgs[i].stripObjCKindOfType(ctx))) {
7105        return false;
7106      }
7107      break;
7108
7109    case ObjCTypeParamVariance::Covariant:
7110      if (!canAssignObjCObjectTypes(ctx, lhsArgs[i], rhsArgs[i]))
7111        return false;
7112      break;
7113
7114    case ObjCTypeParamVariance::Contravariant:
7115      if (!canAssignObjCObjectTypes(ctx, rhsArgs[i], lhsArgs[i]))
7116        return false;
7117      break;
7118    }
7119  }
7120
7121  return true;
7122}
7123
7124QualType ASTContext::areCommonBaseCompatible(
7125           const ObjCObjectPointerType *Lptr,
7126           const ObjCObjectPointerType *Rptr) {
7127  const ObjCObjectType *LHS = Lptr->getObjectType();
7128  const ObjCObjectType *RHS = Rptr->getObjectType();
7129  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
7130  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
7131
7132  if (!LDecl || !RDecl)
7133    return QualType();
7134
7135  // Follow the left-hand side up the class hierarchy until we either hit a
7136  // root or find the RHS. Record the ancestors in case we don't find it.
7137  llvm::SmallDenseMap<const ObjCInterfaceDecl *, const ObjCObjectType *, 4>
7138    LHSAncestors;
7139  while (true) {
7140    // Record this ancestor. We'll need this if the common type isn't in the
7141    // path from the LHS to the root.
7142    LHSAncestors[LHS->getInterface()->getCanonicalDecl()] = LHS;
7143
7144    if (declaresSameEntity(LHS->getInterface(), RDecl)) {
7145      // Get the type arguments.
7146      ArrayRef<QualType> LHSTypeArgs = LHS->getTypeArgsAsWritten();
7147      bool anyChanges = false;
7148      if (LHS->isSpecialized() && RHS->isSpecialized()) {
7149        // Both have type arguments, compare them.
7150        if (!sameObjCTypeArgs(*this, LHS->getInterface(),
7151                              LHS->getTypeArgs(), RHS->getTypeArgs(),
7152                              /*stripKindOf=*/true))
7153          return QualType();
7154      } else if (LHS->isSpecialized() != RHS->isSpecialized()) {
7155        // If only one has type arguments, the result will not have type
7156        // arguments.
7157        LHSTypeArgs = { };
7158        anyChanges = true;
7159      }
7160
7161      // Compute the intersection of protocols.
7162      SmallVector<ObjCProtocolDecl *, 8> Protocols;
7163      getIntersectionOfProtocols(*this, LHS->getInterface(), Lptr, Rptr,
7164                                 Protocols);
7165      if (!Protocols.empty())
7166        anyChanges = true;
7167
7168      // If anything in the LHS will have changed, build a new result type.
7169      if (anyChanges) {
7170        QualType Result = getObjCInterfaceType(LHS->getInterface());
7171        Result = getObjCObjectType(Result, LHSTypeArgs, Protocols,
7172                                   LHS->isKindOfType());
7173        return getObjCObjectPointerType(Result);
7174      }
7175
7176      return getObjCObjectPointerType(QualType(LHS, 0));
7177    }
7178
7179    // Find the superclass.
7180    QualType LHSSuperType = LHS->getSuperClassType();
7181    if (LHSSuperType.isNull())
7182      break;
7183
7184    LHS = LHSSuperType->castAs<ObjCObjectType>();
7185  }
7186
7187  // We didn't find anything by following the LHS to its root; now check
7188  // the RHS against the cached set of ancestors.
7189  while (true) {
7190    auto KnownLHS = LHSAncestors.find(RHS->getInterface()->getCanonicalDecl());
7191    if (KnownLHS != LHSAncestors.end()) {
7192      LHS = KnownLHS->second;
7193
7194      // Get the type arguments.
7195      ArrayRef<QualType> RHSTypeArgs = RHS->getTypeArgsAsWritten();
7196      bool anyChanges = false;
7197      if (LHS->isSpecialized() && RHS->isSpecialized()) {
7198        // Both have type arguments, compare them.
7199        if (!sameObjCTypeArgs(*this, LHS->getInterface(),
7200                              LHS->getTypeArgs(), RHS->getTypeArgs(),
7201                              /*stripKindOf=*/true))
7202          return QualType();
7203      } else if (LHS->isSpecialized() != RHS->isSpecialized()) {
7204        // If only one has type arguments, the result will not have type
7205        // arguments.
7206        RHSTypeArgs = { };
7207        anyChanges = true;
7208      }
7209
7210      // Compute the intersection of protocols.
7211      SmallVector<ObjCProtocolDecl *, 8> Protocols;
7212      getIntersectionOfProtocols(*this, RHS->getInterface(), Lptr, Rptr,
7213                                 Protocols);
7214      if (!Protocols.empty())
7215        anyChanges = true;
7216
7217      if (anyChanges) {
7218        QualType Result = getObjCInterfaceType(RHS->getInterface());
7219        Result = getObjCObjectType(Result, RHSTypeArgs, Protocols,
7220                                   RHS->isKindOfType());
7221        return getObjCObjectPointerType(Result);
7222      }
7223
7224      return getObjCObjectPointerType(QualType(RHS, 0));
7225    }
7226
7227    // Find the superclass of the RHS.
7228    QualType RHSSuperType = RHS->getSuperClassType();
7229    if (RHSSuperType.isNull())
7230      break;
7231
7232    RHS = RHSSuperType->castAs<ObjCObjectType>();
7233  }
7234
7235  return QualType();
7236}
7237
7238bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
7239                                         const ObjCObjectType *RHS) {
7240  assert(LHS->getInterface() && "LHS is not an interface type");
7241  assert(RHS->getInterface() && "RHS is not an interface type");
7242
7243  // Verify that the base decls are compatible: the RHS must be a subclass of
7244  // the LHS.
7245  ObjCInterfaceDecl *LHSInterface = LHS->getInterface();
7246  bool IsSuperClass = LHSInterface->isSuperClassOf(RHS->getInterface());
7247  if (!IsSuperClass)
7248    return false;
7249
7250  // If the LHS has protocol qualifiers, determine whether all of them are
7251  // satisfied by the RHS (i.e., the RHS has a superset of the protocols in the
7252  // LHS).
7253  if (LHS->getNumProtocols() > 0) {
7254    // OK if conversion of LHS to SuperClass results in narrowing of types
7255    // ; i.e., SuperClass may implement at least one of the protocols
7256    // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
7257    // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
7258    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
7259    CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
7260    // Also, if RHS has explicit quelifiers, include them for comparing with LHS's
7261    // qualifiers.
7262    for (auto *RHSPI : RHS->quals())
7263      CollectInheritedProtocols(RHSPI, SuperClassInheritedProtocols);
7264    // If there is no protocols associated with RHS, it is not a match.
7265    if (SuperClassInheritedProtocols.empty())
7266      return false;
7267
7268    for (const auto *LHSProto : LHS->quals()) {
7269      bool SuperImplementsProtocol = false;
7270      for (auto *SuperClassProto : SuperClassInheritedProtocols)
7271        if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
7272          SuperImplementsProtocol = true;
7273          break;
7274        }
7275      if (!SuperImplementsProtocol)
7276        return false;
7277    }
7278  }
7279
7280  // If the LHS is specialized, we may need to check type arguments.
7281  if (LHS->isSpecialized()) {
7282    // Follow the superclass chain until we've matched the LHS class in the
7283    // hierarchy. This substitutes type arguments through.
7284    const ObjCObjectType *RHSSuper = RHS;
7285    while (!declaresSameEntity(RHSSuper->getInterface(), LHSInterface))
7286      RHSSuper = RHSSuper->getSuperClassType()->castAs<ObjCObjectType>();
7287
7288    // If the RHS is specializd, compare type arguments.
7289    if (RHSSuper->isSpecialized() &&
7290        !sameObjCTypeArgs(*this, LHS->getInterface(),
7291                          LHS->getTypeArgs(), RHSSuper->getTypeArgs(),
7292                          /*stripKindOf=*/true)) {
7293      return false;
7294    }
7295  }
7296
7297  return true;
7298}
7299
7300bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
7301  // get the "pointed to" types
7302  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
7303  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
7304
7305  if (!LHSOPT || !RHSOPT)
7306    return false;
7307
7308  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
7309         canAssignObjCInterfaces(RHSOPT, LHSOPT);
7310}
7311
7312bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
7313  return canAssignObjCInterfaces(
7314                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
7315                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
7316}
7317
7318/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
7319/// both shall have the identically qualified version of a compatible type.
7320/// C99 6.2.7p1: Two types have compatible types if their types are the
7321/// same. See 6.7.[2,3,5] for additional rules.
7322bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
7323                                    bool CompareUnqualified) {
7324  if (getLangOpts().CPlusPlus)
7325    return hasSameType(LHS, RHS);
7326
7327  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
7328}
7329
7330bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
7331  return typesAreCompatible(LHS, RHS);
7332}
7333
7334bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
7335  return !mergeTypes(LHS, RHS, true).isNull();
7336}
7337
7338/// mergeTransparentUnionType - if T is a transparent union type and a member
7339/// of T is compatible with SubType, return the merged type, else return
7340/// QualType()
7341QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
7342                                               bool OfBlockPointer,
7343                                               bool Unqualified) {
7344  if (const RecordType *UT = T->getAsUnionType()) {
7345    RecordDecl *UD = UT->getDecl();
7346    if (UD->hasAttr<TransparentUnionAttr>()) {
7347      for (const auto *I : UD->fields()) {
7348        QualType ET = I->getType().getUnqualifiedType();
7349        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
7350        if (!MT.isNull())
7351          return MT;
7352      }
7353    }
7354  }
7355
7356  return QualType();
7357}
7358
7359/// mergeFunctionParameterTypes - merge two types which appear as function
7360/// parameter types
7361QualType ASTContext::mergeFunctionParameterTypes(QualType lhs, QualType rhs,
7362                                                 bool OfBlockPointer,
7363                                                 bool Unqualified) {
7364  // GNU extension: two types are compatible if they appear as a function
7365  // argument, one of the types is a transparent union type and the other
7366  // type is compatible with a union member
7367  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
7368                                              Unqualified);
7369  if (!lmerge.isNull())
7370    return lmerge;
7371
7372  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
7373                                              Unqualified);
7374  if (!rmerge.isNull())
7375    return rmerge;
7376
7377  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
7378}
7379
7380QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
7381                                        bool OfBlockPointer,
7382                                        bool Unqualified) {
7383  const FunctionType *lbase = lhs->getAs<FunctionType>();
7384  const FunctionType *rbase = rhs->getAs<FunctionType>();
7385  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
7386  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
7387  bool allLTypes = true;
7388  bool allRTypes = true;
7389
7390  // Check return type
7391  QualType retType;
7392  if (OfBlockPointer) {
7393    QualType RHS = rbase->getReturnType();
7394    QualType LHS = lbase->getReturnType();
7395    bool UnqualifiedResult = Unqualified;
7396    if (!UnqualifiedResult)
7397      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
7398    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
7399  }
7400  else
7401    retType = mergeTypes(lbase->getReturnType(), rbase->getReturnType(), false,
7402                         Unqualified);
7403  if (retType.isNull()) return QualType();
7404
7405  if (Unqualified)
7406    retType = retType.getUnqualifiedType();
7407
7408  CanQualType LRetType = getCanonicalType(lbase->getReturnType());
7409  CanQualType RRetType = getCanonicalType(rbase->getReturnType());
7410  if (Unqualified) {
7411    LRetType = LRetType.getUnqualifiedType();
7412    RRetType = RRetType.getUnqualifiedType();
7413  }
7414
7415  if (getCanonicalType(retType) != LRetType)
7416    allLTypes = false;
7417  if (getCanonicalType(retType) != RRetType)
7418    allRTypes = false;
7419
7420  // FIXME: double check this
7421  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
7422  //                           rbase->getRegParmAttr() != 0 &&
7423  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
7424  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
7425  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
7426
7427  // Compatible functions must have compatible calling conventions
7428  if (lbaseInfo.getCC() != rbaseInfo.getCC())
7429    return QualType();
7430
7431  // Regparm is part of the calling convention.
7432  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
7433    return QualType();
7434  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
7435    return QualType();
7436
7437  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
7438    return QualType();
7439
7440  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
7441  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
7442
7443  if (lbaseInfo.getNoReturn() != NoReturn)
7444    allLTypes = false;
7445  if (rbaseInfo.getNoReturn() != NoReturn)
7446    allRTypes = false;
7447
7448  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
7449
7450  if (lproto && rproto) { // two C99 style function prototypes
7451    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
7452           "C++ shouldn't be here");
7453    // Compatible functions must have the same number of parameters
7454    if (lproto->getNumParams() != rproto->getNumParams())
7455      return QualType();
7456
7457    // Variadic and non-variadic functions aren't compatible
7458    if (lproto->isVariadic() != rproto->isVariadic())
7459      return QualType();
7460
7461    if (lproto->getTypeQuals() != rproto->getTypeQuals())
7462      return QualType();
7463
7464    if (LangOpts.ObjCAutoRefCount &&
7465        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
7466      return QualType();
7467
7468    // Check parameter type compatibility
7469    SmallVector<QualType, 10> types;
7470    for (unsigned i = 0, n = lproto->getNumParams(); i < n; i++) {
7471      QualType lParamType = lproto->getParamType(i).getUnqualifiedType();
7472      QualType rParamType = rproto->getParamType(i).getUnqualifiedType();
7473      QualType paramType = mergeFunctionParameterTypes(
7474          lParamType, rParamType, OfBlockPointer, Unqualified);
7475      if (paramType.isNull())
7476        return QualType();
7477
7478      if (Unqualified)
7479        paramType = paramType.getUnqualifiedType();
7480
7481      types.push_back(paramType);
7482      if (Unqualified) {
7483        lParamType = lParamType.getUnqualifiedType();
7484        rParamType = rParamType.getUnqualifiedType();
7485      }
7486
7487      if (getCanonicalType(paramType) != getCanonicalType(lParamType))
7488        allLTypes = false;
7489      if (getCanonicalType(paramType) != getCanonicalType(rParamType))
7490        allRTypes = false;
7491    }
7492
7493    if (allLTypes) return lhs;
7494    if (allRTypes) return rhs;
7495
7496    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
7497    EPI.ExtInfo = einfo;
7498    return getFunctionType(retType, types, EPI);
7499  }
7500
7501  if (lproto) allRTypes = false;
7502  if (rproto) allLTypes = false;
7503
7504  const FunctionProtoType *proto = lproto ? lproto : rproto;
7505  if (proto) {
7506    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
7507    if (proto->isVariadic()) return QualType();
7508    // Check that the types are compatible with the types that
7509    // would result from default argument promotions (C99 6.7.5.3p15).
7510    // The only types actually affected are promotable integer
7511    // types and floats, which would be passed as a different
7512    // type depending on whether the prototype is visible.
7513    for (unsigned i = 0, n = proto->getNumParams(); i < n; ++i) {
7514      QualType paramTy = proto->getParamType(i);
7515
7516      // Look at the converted type of enum types, since that is the type used
7517      // to pass enum values.
7518      if (const EnumType *Enum = paramTy->getAs<EnumType>()) {
7519        paramTy = Enum->getDecl()->getIntegerType();
7520        if (paramTy.isNull())
7521          return QualType();
7522      }
7523
7524      if (paramTy->isPromotableIntegerType() ||
7525          getCanonicalType(paramTy).getUnqualifiedType() == FloatTy)
7526        return QualType();
7527    }
7528
7529    if (allLTypes) return lhs;
7530    if (allRTypes) return rhs;
7531
7532    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
7533    EPI.ExtInfo = einfo;
7534    return getFunctionType(retType, proto->getParamTypes(), EPI);
7535  }
7536
7537  if (allLTypes) return lhs;
7538  if (allRTypes) return rhs;
7539  return getFunctionNoProtoType(retType, einfo);
7540}
7541
7542/// Given that we have an enum type and a non-enum type, try to merge them.
7543static QualType mergeEnumWithInteger(ASTContext &Context, const EnumType *ET,
7544                                     QualType other, bool isBlockReturnType) {
7545  // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
7546  // a signed integer type, or an unsigned integer type.
7547  // Compatibility is based on the underlying type, not the promotion
7548  // type.
7549  QualType underlyingType = ET->getDecl()->getIntegerType();
7550  if (underlyingType.isNull()) return QualType();
7551  if (Context.hasSameType(underlyingType, other))
7552    return other;
7553
7554  // In block return types, we're more permissive and accept any
7555  // integral type of the same size.
7556  if (isBlockReturnType && other->isIntegerType() &&
7557      Context.getTypeSize(underlyingType) == Context.getTypeSize(other))
7558    return other;
7559
7560  return QualType();
7561}
7562
7563QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
7564                                bool OfBlockPointer,
7565                                bool Unqualified, bool BlockReturnType) {
7566  // C++ [expr]: If an expression initially has the type "reference to T", the
7567  // type is adjusted to "T" prior to any further analysis, the expression
7568  // designates the object or function denoted by the reference, and the
7569  // expression is an lvalue unless the reference is an rvalue reference and
7570  // the expression is a function call (possibly inside parentheses).
7571  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
7572  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
7573
7574  if (Unqualified) {
7575    LHS = LHS.getUnqualifiedType();
7576    RHS = RHS.getUnqualifiedType();
7577  }
7578
7579  QualType LHSCan = getCanonicalType(LHS),
7580           RHSCan = getCanonicalType(RHS);
7581
7582  // If two types are identical, they are compatible.
7583  if (LHSCan == RHSCan)
7584    return LHS;
7585
7586  // If the qualifiers are different, the types aren't compatible... mostly.
7587  Qualifiers LQuals = LHSCan.getLocalQualifiers();
7588  Qualifiers RQuals = RHSCan.getLocalQualifiers();
7589  if (LQuals != RQuals) {
7590    // If any of these qualifiers are different, we have a type
7591    // mismatch.
7592    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
7593        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
7594        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
7595      return QualType();
7596
7597    // Exactly one GC qualifier difference is allowed: __strong is
7598    // okay if the other type has no GC qualifier but is an Objective
7599    // C object pointer (i.e. implicitly strong by default).  We fix
7600    // this by pretending that the unqualified type was actually
7601    // qualified __strong.
7602    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
7603    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
7604    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
7605
7606    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
7607      return QualType();
7608
7609    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
7610      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
7611    }
7612    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
7613      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
7614    }
7615    return QualType();
7616  }
7617
7618  // Okay, qualifiers are equal.
7619
7620  Type::TypeClass LHSClass = LHSCan->getTypeClass();
7621  Type::TypeClass RHSClass = RHSCan->getTypeClass();
7622
7623  // We want to consider the two function types to be the same for these
7624  // comparisons, just force one to the other.
7625  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
7626  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
7627
7628  // Same as above for arrays
7629  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
7630    LHSClass = Type::ConstantArray;
7631  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
7632    RHSClass = Type::ConstantArray;
7633
7634  // ObjCInterfaces are just specialized ObjCObjects.
7635  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
7636  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
7637
7638  // Canonicalize ExtVector -> Vector.
7639  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
7640  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
7641
7642  // If the canonical type classes don't match.
7643  if (LHSClass != RHSClass) {
7644    // Note that we only have special rules for turning block enum
7645    // returns into block int returns, not vice-versa.
7646    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
7647      return mergeEnumWithInteger(*this, ETy, RHS, false);
7648    }
7649    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
7650      return mergeEnumWithInteger(*this, ETy, LHS, BlockReturnType);
7651    }
7652    // allow block pointer type to match an 'id' type.
7653    if (OfBlockPointer && !BlockReturnType) {
7654       if (LHS->isObjCIdType() && RHS->isBlockPointerType())
7655         return LHS;
7656      if (RHS->isObjCIdType() && LHS->isBlockPointerType())
7657        return RHS;
7658    }
7659
7660    return QualType();
7661  }
7662
7663  // The canonical type classes match.
7664  switch (LHSClass) {
7665#define TYPE(Class, Base)
7666#define ABSTRACT_TYPE(Class, Base)
7667#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
7668#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
7669#define DEPENDENT_TYPE(Class, Base) case Type::Class:
7670#include "clang/AST/TypeNodes.def"
7671    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
7672
7673  case Type::Auto:
7674  case Type::LValueReference:
7675  case Type::RValueReference:
7676  case Type::MemberPointer:
7677    llvm_unreachable("C++ should never be in mergeTypes");
7678
7679  case Type::ObjCInterface:
7680  case Type::IncompleteArray:
7681  case Type::VariableArray:
7682  case Type::FunctionProto:
7683  case Type::ExtVector:
7684    llvm_unreachable("Types are eliminated above");
7685
7686  case Type::Pointer:
7687  {
7688    // Merge two pointer types, while trying to preserve typedef info
7689    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
7690    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
7691    if (Unqualified) {
7692      LHSPointee = LHSPointee.getUnqualifiedType();
7693      RHSPointee = RHSPointee.getUnqualifiedType();
7694    }
7695    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
7696                                     Unqualified);
7697    if (ResultType.isNull()) return QualType();
7698    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
7699      return LHS;
7700    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
7701      return RHS;
7702    return getPointerType(ResultType);
7703  }
7704  case Type::BlockPointer:
7705  {
7706    // Merge two block pointer types, while trying to preserve typedef info
7707    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
7708    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
7709    if (Unqualified) {
7710      LHSPointee = LHSPointee.getUnqualifiedType();
7711      RHSPointee = RHSPointee.getUnqualifiedType();
7712    }
7713    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
7714                                     Unqualified);
7715    if (ResultType.isNull()) return QualType();
7716    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
7717      return LHS;
7718    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
7719      return RHS;
7720    return getBlockPointerType(ResultType);
7721  }
7722  case Type::Atomic:
7723  {
7724    // Merge two pointer types, while trying to preserve typedef info
7725    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
7726    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
7727    if (Unqualified) {
7728      LHSValue = LHSValue.getUnqualifiedType();
7729      RHSValue = RHSValue.getUnqualifiedType();
7730    }
7731    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
7732                                     Unqualified);
7733    if (ResultType.isNull()) return QualType();
7734    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
7735      return LHS;
7736    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
7737      return RHS;
7738    return getAtomicType(ResultType);
7739  }
7740  case Type::ConstantArray:
7741  {
7742    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
7743    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
7744    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
7745      return QualType();
7746
7747    QualType LHSElem = getAsArrayType(LHS)->getElementType();
7748    QualType RHSElem = getAsArrayType(RHS)->getElementType();
7749    if (Unqualified) {
7750      LHSElem = LHSElem.getUnqualifiedType();
7751      RHSElem = RHSElem.getUnqualifiedType();
7752    }
7753
7754    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
7755    if (ResultType.isNull()) return QualType();
7756    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
7757      return LHS;
7758    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
7759      return RHS;
7760    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
7761                                          ArrayType::ArraySizeModifier(), 0);
7762    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
7763                                          ArrayType::ArraySizeModifier(), 0);
7764    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
7765    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
7766    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
7767      return LHS;
7768    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
7769      return RHS;
7770    if (LVAT) {
7771      // FIXME: This isn't correct! But tricky to implement because
7772      // the array's size has to be the size of LHS, but the type
7773      // has to be different.
7774      return LHS;
7775    }
7776    if (RVAT) {
7777      // FIXME: This isn't correct! But tricky to implement because
7778      // the array's size has to be the size of RHS, but the type
7779      // has to be different.
7780      return RHS;
7781    }
7782    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
7783    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
7784    return getIncompleteArrayType(ResultType,
7785                                  ArrayType::ArraySizeModifier(), 0);
7786  }
7787  case Type::FunctionNoProto:
7788    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
7789  case Type::Record:
7790  case Type::Enum:
7791    return QualType();
7792  case Type::Builtin:
7793    // Only exactly equal builtin types are compatible, which is tested above.
7794    return QualType();
7795  case Type::Complex:
7796    // Distinct complex types are incompatible.
7797    return QualType();
7798  case Type::Vector:
7799    // FIXME: The merged type should be an ExtVector!
7800    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
7801                             RHSCan->getAs<VectorType>()))
7802      return LHS;
7803    return QualType();
7804  case Type::ObjCObject: {
7805    // Check if the types are assignment compatible.
7806    // FIXME: This should be type compatibility, e.g. whether
7807    // "LHS x; RHS x;" at global scope is legal.
7808    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
7809    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
7810    if (canAssignObjCInterfaces(LHSIface, RHSIface))
7811      return LHS;
7812
7813    return QualType();
7814  }
7815  case Type::ObjCObjectPointer: {
7816    if (OfBlockPointer) {
7817      if (canAssignObjCInterfacesInBlockPointer(
7818                                          LHS->getAs<ObjCObjectPointerType>(),
7819                                          RHS->getAs<ObjCObjectPointerType>(),
7820                                          BlockReturnType))
7821        return LHS;
7822      return QualType();
7823    }
7824    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
7825                                RHS->getAs<ObjCObjectPointerType>()))
7826      return LHS;
7827
7828    return QualType();
7829  }
7830  case Type::Pipe:
7831  {
7832    // Merge two pointer types, while trying to preserve typedef info
7833    QualType LHSValue = LHS->getAs<PipeType>()->getElementType();
7834    QualType RHSValue = RHS->getAs<PipeType>()->getElementType();
7835    if (Unqualified) {
7836      LHSValue = LHSValue.getUnqualifiedType();
7837      RHSValue = RHSValue.getUnqualifiedType();
7838    }
7839    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
7840                                     Unqualified);
7841    if (ResultType.isNull()) return QualType();
7842    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
7843      return LHS;
7844    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
7845      return RHS;
7846    return getPipeType(ResultType);
7847  }
7848  }
7849
7850  llvm_unreachable("Invalid Type::Class!");
7851}
7852
7853bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
7854                   const FunctionProtoType *FromFunctionType,
7855                   const FunctionProtoType *ToFunctionType) {
7856  if (FromFunctionType->hasAnyConsumedParams() !=
7857      ToFunctionType->hasAnyConsumedParams())
7858    return false;
7859  FunctionProtoType::ExtProtoInfo FromEPI =
7860    FromFunctionType->getExtProtoInfo();
7861  FunctionProtoType::ExtProtoInfo ToEPI =
7862    ToFunctionType->getExtProtoInfo();
7863  if (FromEPI.ConsumedParameters && ToEPI.ConsumedParameters)
7864    for (unsigned i = 0, n = FromFunctionType->getNumParams(); i != n; ++i) {
7865      if (FromEPI.ConsumedParameters[i] != ToEPI.ConsumedParameters[i])
7866        return false;
7867    }
7868  return true;
7869}
7870
7871void ASTContext::ResetObjCLayout(const ObjCContainerDecl *CD) {
7872  ObjCLayouts[CD] = nullptr;
7873}
7874
7875/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
7876/// 'RHS' attributes and returns the merged version; including for function
7877/// return types.
7878QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
7879  QualType LHSCan = getCanonicalType(LHS),
7880  RHSCan = getCanonicalType(RHS);
7881  // If two types are identical, they are compatible.
7882  if (LHSCan == RHSCan)
7883    return LHS;
7884  if (RHSCan->isFunctionType()) {
7885    if (!LHSCan->isFunctionType())
7886      return QualType();
7887    QualType OldReturnType =
7888        cast<FunctionType>(RHSCan.getTypePtr())->getReturnType();
7889    QualType NewReturnType =
7890        cast<FunctionType>(LHSCan.getTypePtr())->getReturnType();
7891    QualType ResReturnType =
7892      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
7893    if (ResReturnType.isNull())
7894      return QualType();
7895    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
7896      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
7897      // In either case, use OldReturnType to build the new function type.
7898      const FunctionType *F = LHS->getAs<FunctionType>();
7899      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
7900        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
7901        EPI.ExtInfo = getFunctionExtInfo(LHS);
7902        QualType ResultType =
7903            getFunctionType(OldReturnType, FPT->getParamTypes(), EPI);
7904        return ResultType;
7905      }
7906    }
7907    return QualType();
7908  }
7909
7910  // If the qualifiers are different, the types can still be merged.
7911  Qualifiers LQuals = LHSCan.getLocalQualifiers();
7912  Qualifiers RQuals = RHSCan.getLocalQualifiers();
7913  if (LQuals != RQuals) {
7914    // If any of these qualifiers are different, we have a type mismatch.
7915    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
7916        LQuals.getAddressSpace() != RQuals.getAddressSpace())
7917      return QualType();
7918
7919    // Exactly one GC qualifier difference is allowed: __strong is
7920    // okay if the other type has no GC qualifier but is an Objective
7921    // C object pointer (i.e. implicitly strong by default).  We fix
7922    // this by pretending that the unqualified type was actually
7923    // qualified __strong.
7924    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
7925    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
7926    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
7927
7928    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
7929      return QualType();
7930
7931    if (GC_L == Qualifiers::Strong)
7932      return LHS;
7933    if (GC_R == Qualifiers::Strong)
7934      return RHS;
7935    return QualType();
7936  }
7937
7938  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
7939    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
7940    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
7941    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
7942    if (ResQT == LHSBaseQT)
7943      return LHS;
7944    if (ResQT == RHSBaseQT)
7945      return RHS;
7946  }
7947  return QualType();
7948}
7949
7950//===----------------------------------------------------------------------===//
7951//                         Integer Predicates
7952//===----------------------------------------------------------------------===//
7953
7954unsigned ASTContext::getIntWidth(QualType T) const {
7955  if (const EnumType *ET = T->getAs<EnumType>())
7956    T = ET->getDecl()->getIntegerType();
7957  if (T->isBooleanType())
7958    return 1;
7959  // For builtin types, just use the standard type sizing method
7960  return (unsigned)getTypeSize(T);
7961}
7962
7963QualType ASTContext::getCorrespondingUnsignedType(QualType T) const {
7964  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
7965
7966  // Turn <4 x signed int> -> <4 x unsigned int>
7967  if (const VectorType *VTy = T->getAs<VectorType>())
7968    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
7969                         VTy->getNumElements(), VTy->getVectorKind());
7970
7971  // For enums, we return the unsigned version of the base type.
7972  if (const EnumType *ETy = T->getAs<EnumType>())
7973    T = ETy->getDecl()->getIntegerType();
7974
7975  const BuiltinType *BTy = T->getAs<BuiltinType>();
7976  assert(BTy && "Unexpected signed integer type");
7977  switch (BTy->getKind()) {
7978  case BuiltinType::Char_S:
7979  case BuiltinType::SChar:
7980    return UnsignedCharTy;
7981  case BuiltinType::Short:
7982    return UnsignedShortTy;
7983  case BuiltinType::Int:
7984    return UnsignedIntTy;
7985  case BuiltinType::Long:
7986    return UnsignedLongTy;
7987  case BuiltinType::LongLong:
7988    return UnsignedLongLongTy;
7989  case BuiltinType::Int128:
7990    return UnsignedInt128Ty;
7991  default:
7992    llvm_unreachable("Unexpected signed integer type");
7993  }
7994}
7995
7996ASTMutationListener::~ASTMutationListener() { }
7997
7998void ASTMutationListener::DeducedReturnType(const FunctionDecl *FD,
7999                                            QualType ReturnType) {}
8000
8001//===----------------------------------------------------------------------===//
8002//                          Builtin Type Computation
8003//===----------------------------------------------------------------------===//
8004
8005/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
8006/// pointer over the consumed characters.  This returns the resultant type.  If
8007/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
8008/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
8009/// a vector of "i*".
8010///
8011/// RequiresICE is filled in on return to indicate whether the value is required
8012/// to be an Integer Constant Expression.
8013static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
8014                                  ASTContext::GetBuiltinTypeError &Error,
8015                                  bool &RequiresICE,
8016                                  bool AllowTypeModifiers) {
8017  // Modifiers.
8018  int HowLong = 0;
8019  bool Signed = false, Unsigned = false;
8020  RequiresICE = false;
8021
8022  // Read the prefixed modifiers first.
8023  bool Done = false;
8024  while (!Done) {
8025    switch (*Str++) {
8026    default: Done = true; --Str; break;
8027    case 'I':
8028      RequiresICE = true;
8029      break;
8030    case 'S':
8031      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
8032      assert(!Signed && "Can't use 'S' modifier multiple times!");
8033      Signed = true;
8034      break;
8035    case 'U':
8036      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
8037      assert(!Unsigned && "Can't use 'U' modifier multiple times!");
8038      Unsigned = true;
8039      break;
8040    case 'L':
8041      assert(HowLong <= 2 && "Can't have LLLL modifier");
8042      ++HowLong;
8043      break;
8044    case 'W':
8045      // This modifier represents int64 type.
8046      assert(HowLong == 0 && "Can't use both 'L' and 'W' modifiers!");
8047      switch (Context.getTargetInfo().getInt64Type()) {
8048      default:
8049        llvm_unreachable("Unexpected integer type");
8050      case TargetInfo::SignedLong:
8051        HowLong = 1;
8052        break;
8053      case TargetInfo::SignedLongLong:
8054        HowLong = 2;
8055        break;
8056      }
8057    }
8058  }
8059
8060  QualType Type;
8061
8062  // Read the base type.
8063  switch (*Str++) {
8064  default: llvm_unreachable("Unknown builtin type letter!");
8065  case 'v':
8066    assert(HowLong == 0 && !Signed && !Unsigned &&
8067           "Bad modifiers used with 'v'!");
8068    Type = Context.VoidTy;
8069    break;
8070  case 'h':
8071    assert(HowLong == 0 && !Signed && !Unsigned &&
8072           "Bad modifiers used with 'h'!");
8073    Type = Context.HalfTy;
8074    break;
8075  case 'f':
8076    assert(HowLong == 0 && !Signed && !Unsigned &&
8077           "Bad modifiers used with 'f'!");
8078    Type = Context.FloatTy;
8079    break;
8080  case 'd':
8081    assert(HowLong < 2 && !Signed && !Unsigned &&
8082           "Bad modifiers used with 'd'!");
8083    if (HowLong)
8084      Type = Context.LongDoubleTy;
8085    else
8086      Type = Context.DoubleTy;
8087    break;
8088  case 's':
8089    assert(HowLong == 0 && "Bad modifiers used with 's'!");
8090    if (Unsigned)
8091      Type = Context.UnsignedShortTy;
8092    else
8093      Type = Context.ShortTy;
8094    break;
8095  case 'i':
8096    if (HowLong == 3)
8097      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
8098    else if (HowLong == 2)
8099      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
8100    else if (HowLong == 1)
8101      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
8102    else
8103      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
8104    break;
8105  case 'c':
8106    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
8107    if (Signed)
8108      Type = Context.SignedCharTy;
8109    else if (Unsigned)
8110      Type = Context.UnsignedCharTy;
8111    else
8112      Type = Context.CharTy;
8113    break;
8114  case 'b': // boolean
8115    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
8116    Type = Context.BoolTy;
8117    break;
8118  case 'z':  // size_t.
8119    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
8120    Type = Context.getSizeType();
8121    break;
8122  case 'F':
8123    Type = Context.getCFConstantStringType();
8124    break;
8125  case 'G':
8126    Type = Context.getObjCIdType();
8127    break;
8128  case 'H':
8129    Type = Context.getObjCSelType();
8130    break;
8131  case 'M':
8132    Type = Context.getObjCSuperType();
8133    break;
8134  case 'a':
8135    Type = Context.getBuiltinVaListType();
8136    assert(!Type.isNull() && "builtin va list type not initialized!");
8137    break;
8138  case 'A':
8139    // This is a "reference" to a va_list; however, what exactly
8140    // this means depends on how va_list is defined. There are two
8141    // different kinds of va_list: ones passed by value, and ones
8142    // passed by reference.  An example of a by-value va_list is
8143    // x86, where va_list is a char*. An example of by-ref va_list
8144    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
8145    // we want this argument to be a char*&; for x86-64, we want
8146    // it to be a __va_list_tag*.
8147    Type = Context.getBuiltinVaListType();
8148    assert(!Type.isNull() && "builtin va list type not initialized!");
8149    if (Type->isArrayType())
8150      Type = Context.getArrayDecayedType(Type);
8151    else
8152      Type = Context.getLValueReferenceType(Type);
8153    break;
8154  case 'V': {
8155    char *End;
8156    unsigned NumElements = strtoul(Str, &End, 10);
8157    assert(End != Str && "Missing vector size");
8158    Str = End;
8159
8160    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
8161                                             RequiresICE, false);
8162    assert(!RequiresICE && "Can't require vector ICE");
8163
8164    // TODO: No way to make AltiVec vectors in builtins yet.
8165    Type = Context.getVectorType(ElementType, NumElements,
8166                                 VectorType::GenericVector);
8167    break;
8168  }
8169  case 'E': {
8170    char *End;
8171
8172    unsigned NumElements = strtoul(Str, &End, 10);
8173    assert(End != Str && "Missing vector size");
8174
8175    Str = End;
8176
8177    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
8178                                             false);
8179    Type = Context.getExtVectorType(ElementType, NumElements);
8180    break;
8181  }
8182  case 'X': {
8183    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
8184                                             false);
8185    assert(!RequiresICE && "Can't require complex ICE");
8186    Type = Context.getComplexType(ElementType);
8187    break;
8188  }
8189  case 'Y' : {
8190    Type = Context.getPointerDiffType();
8191    break;
8192  }
8193  case 'P':
8194    Type = Context.getFILEType();
8195    if (Type.isNull()) {
8196      Error = ASTContext::GE_Missing_stdio;
8197      return QualType();
8198    }
8199    break;
8200  case 'J':
8201    if (Signed)
8202      Type = Context.getsigjmp_bufType();
8203    else
8204      Type = Context.getjmp_bufType();
8205
8206    if (Type.isNull()) {
8207      Error = ASTContext::GE_Missing_setjmp;
8208      return QualType();
8209    }
8210    break;
8211  case 'K':
8212    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'K'!");
8213    Type = Context.getucontext_tType();
8214
8215    if (Type.isNull()) {
8216      Error = ASTContext::GE_Missing_ucontext;
8217      return QualType();
8218    }
8219    break;
8220  case 'p':
8221    Type = Context.getProcessIDType();
8222    break;
8223  }
8224
8225  // If there are modifiers and if we're allowed to parse them, go for it.
8226  Done = !AllowTypeModifiers;
8227  while (!Done) {
8228    switch (char c = *Str++) {
8229    default: Done = true; --Str; break;
8230    case '*':
8231    case '&': {
8232      // Both pointers and references can have their pointee types
8233      // qualified with an address space.
8234      char *End;
8235      unsigned AddrSpace = strtoul(Str, &End, 10);
8236      if (End != Str && AddrSpace != 0) {
8237        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
8238        Str = End;
8239      }
8240      if (c == '*')
8241        Type = Context.getPointerType(Type);
8242      else
8243        Type = Context.getLValueReferenceType(Type);
8244      break;
8245    }
8246    // FIXME: There's no way to have a built-in with an rvalue ref arg.
8247    case 'C':
8248      Type = Type.withConst();
8249      break;
8250    case 'D':
8251      Type = Context.getVolatileType(Type);
8252      break;
8253    case 'R':
8254      Type = Type.withRestrict();
8255      break;
8256    }
8257  }
8258
8259  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
8260         "Integer constant 'I' type must be an integer");
8261
8262  return Type;
8263}
8264
8265/// GetBuiltinType - Return the type for the specified builtin.
8266QualType ASTContext::GetBuiltinType(unsigned Id,
8267                                    GetBuiltinTypeError &Error,
8268                                    unsigned *IntegerConstantArgs) const {
8269  const char *TypeStr = BuiltinInfo.getTypeString(Id);
8270
8271  SmallVector<QualType, 8> ArgTypes;
8272
8273  bool RequiresICE = false;
8274  Error = GE_None;
8275  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
8276                                       RequiresICE, true);
8277  if (Error != GE_None)
8278    return QualType();
8279
8280  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
8281
8282  while (TypeStr[0] && TypeStr[0] != '.') {
8283    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
8284    if (Error != GE_None)
8285      return QualType();
8286
8287    // If this argument is required to be an IntegerConstantExpression and the
8288    // caller cares, fill in the bitmask we return.
8289    if (RequiresICE && IntegerConstantArgs)
8290      *IntegerConstantArgs |= 1 << ArgTypes.size();
8291
8292    // Do array -> pointer decay.  The builtin should use the decayed type.
8293    if (Ty->isArrayType())
8294      Ty = getArrayDecayedType(Ty);
8295
8296    ArgTypes.push_back(Ty);
8297  }
8298
8299  if (Id == Builtin::BI__GetExceptionInfo)
8300    return QualType();
8301
8302  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
8303         "'.' should only occur at end of builtin type list!");
8304
8305  FunctionType::ExtInfo EI(CC_C);
8306  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
8307
8308  bool Variadic = (TypeStr[0] == '.');
8309
8310  // We really shouldn't be making a no-proto type here, especially in C++.
8311  if (ArgTypes.empty() && Variadic)
8312    return getFunctionNoProtoType(ResType, EI);
8313
8314  FunctionProtoType::ExtProtoInfo EPI;
8315  EPI.ExtInfo = EI;
8316  EPI.Variadic = Variadic;
8317
8318  return getFunctionType(ResType, ArgTypes, EPI);
8319}
8320
8321static GVALinkage basicGVALinkageForFunction(const ASTContext &Context,
8322                                             const FunctionDecl *FD) {
8323  if (!FD->isExternallyVisible())
8324    return GVA_Internal;
8325
8326  GVALinkage External = GVA_StrongExternal;
8327  switch (FD->getTemplateSpecializationKind()) {
8328  case TSK_Undeclared:
8329  case TSK_ExplicitSpecialization:
8330    External = GVA_StrongExternal;
8331    break;
8332
8333  case TSK_ExplicitInstantiationDefinition:
8334    return GVA_StrongODR;
8335
8336  // C++11 [temp.explicit]p10:
8337  //   [ Note: The intent is that an inline function that is the subject of
8338  //   an explicit instantiation declaration will still be implicitly
8339  //   instantiated when used so that the body can be considered for
8340  //   inlining, but that no out-of-line copy of the inline function would be
8341  //   generated in the translation unit. -- end note ]
8342  case TSK_ExplicitInstantiationDeclaration:
8343    return GVA_AvailableExternally;
8344
8345  case TSK_ImplicitInstantiation:
8346    External = GVA_DiscardableODR;
8347    break;
8348  }
8349
8350  if (!FD->isInlined())
8351    return External;
8352
8353  if ((!Context.getLangOpts().CPlusPlus &&
8354       !Context.getTargetInfo().getCXXABI().isMicrosoft() &&
8355       !FD->hasAttr<DLLExportAttr>()) ||
8356      FD->hasAttr<GNUInlineAttr>()) {
8357    // FIXME: This doesn't match gcc's behavior for dllexport inline functions.
8358
8359    // GNU or C99 inline semantics. Determine whether this symbol should be
8360    // externally visible.
8361    if (FD->isInlineDefinitionExternallyVisible())
8362      return External;
8363
8364    // C99 inline semantics, where the symbol is not externally visible.
8365    return GVA_AvailableExternally;
8366  }
8367
8368  // Functions specified with extern and inline in -fms-compatibility mode
8369  // forcibly get emitted.  While the body of the function cannot be later
8370  // replaced, the function definition cannot be discarded.
8371  if (FD->isMSExternInline())
8372    return GVA_StrongODR;
8373
8374  return GVA_DiscardableODR;
8375}
8376
8377static GVALinkage adjustGVALinkageForAttributes(GVALinkage L, const Decl *D) {
8378  // See http://msdn.microsoft.com/en-us/library/xa0d9ste.aspx
8379  // dllexport/dllimport on inline functions.
8380  if (D->hasAttr<DLLImportAttr>()) {
8381    if (L == GVA_DiscardableODR || L == GVA_StrongODR)
8382      return GVA_AvailableExternally;
8383  } else if (D->hasAttr<DLLExportAttr>() || D->hasAttr<CUDAGlobalAttr>()) {
8384    if (L == GVA_DiscardableODR)
8385      return GVA_StrongODR;
8386  }
8387  return L;
8388}
8389
8390GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) const {
8391  return adjustGVALinkageForAttributes(basicGVALinkageForFunction(*this, FD),
8392                                       FD);
8393}
8394
8395static GVALinkage basicGVALinkageForVariable(const ASTContext &Context,
8396                                             const VarDecl *VD) {
8397  if (!VD->isExternallyVisible())
8398    return GVA_Internal;
8399
8400  if (VD->isStaticLocal()) {
8401    GVALinkage StaticLocalLinkage = GVA_DiscardableODR;
8402    const DeclContext *LexicalContext = VD->getParentFunctionOrMethod();
8403    while (LexicalContext && !isa<FunctionDecl>(LexicalContext))
8404      LexicalContext = LexicalContext->getLexicalParent();
8405
8406    // Let the static local variable inherit its linkage from the nearest
8407    // enclosing function.
8408    if (LexicalContext)
8409      StaticLocalLinkage =
8410          Context.GetGVALinkageForFunction(cast<FunctionDecl>(LexicalContext));
8411
8412    // GVA_StrongODR function linkage is stronger than what we need,
8413    // downgrade to GVA_DiscardableODR.
8414    // This allows us to discard the variable if we never end up needing it.
8415    return StaticLocalLinkage == GVA_StrongODR ? GVA_DiscardableODR
8416                                               : StaticLocalLinkage;
8417  }
8418
8419  // MSVC treats in-class initialized static data members as definitions.
8420  // By giving them non-strong linkage, out-of-line definitions won't
8421  // cause link errors.
8422  if (Context.isMSStaticDataMemberInlineDefinition(VD))
8423    return GVA_DiscardableODR;
8424
8425  switch (VD->getTemplateSpecializationKind()) {
8426  case TSK_Undeclared:
8427    return GVA_StrongExternal;
8428
8429  case TSK_ExplicitSpecialization:
8430    return Context.getTargetInfo().getCXXABI().isMicrosoft() &&
8431                   VD->isStaticDataMember()
8432               ? GVA_StrongODR
8433               : GVA_StrongExternal;
8434
8435  case TSK_ExplicitInstantiationDefinition:
8436    return GVA_StrongODR;
8437
8438  case TSK_ExplicitInstantiationDeclaration:
8439    return GVA_AvailableExternally;
8440
8441  case TSK_ImplicitInstantiation:
8442    return GVA_DiscardableODR;
8443  }
8444
8445  llvm_unreachable("Invalid Linkage!");
8446}
8447
8448GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
8449  return adjustGVALinkageForAttributes(basicGVALinkageForVariable(*this, VD),
8450                                       VD);
8451}
8452
8453bool ASTContext::DeclMustBeEmitted(const Decl *D) {
8454  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
8455    if (!VD->isFileVarDecl())
8456      return false;
8457    // Global named register variables (GNU extension) are never emitted.
8458    if (VD->getStorageClass() == SC_Register)
8459      return false;
8460    if (VD->getDescribedVarTemplate() ||
8461        isa<VarTemplatePartialSpecializationDecl>(VD))
8462      return false;
8463  } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
8464    // We never need to emit an uninstantiated function template.
8465    if (FD->getTemplatedKind() == FunctionDecl::TK_FunctionTemplate)
8466      return false;
8467  } else if (isa<OMPThreadPrivateDecl>(D))
8468    return true;
8469  else
8470    return false;
8471
8472  // If this is a member of a class template, we do not need to emit it.
8473  if (D->getDeclContext()->isDependentContext())
8474    return false;
8475
8476  // Weak references don't produce any output by themselves.
8477  if (D->hasAttr<WeakRefAttr>())
8478    return false;
8479
8480  // Aliases and used decls are required.
8481  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
8482    return true;
8483
8484  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
8485    // Forward declarations aren't required.
8486    if (!FD->doesThisDeclarationHaveABody())
8487      return FD->doesDeclarationForceExternallyVisibleDefinition();
8488
8489    // Constructors and destructors are required.
8490    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
8491      return true;
8492
8493    // The key function for a class is required.  This rule only comes
8494    // into play when inline functions can be key functions, though.
8495    if (getTargetInfo().getCXXABI().canKeyFunctionBeInline()) {
8496      if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
8497        const CXXRecordDecl *RD = MD->getParent();
8498        if (MD->isOutOfLine() && RD->isDynamicClass()) {
8499          const CXXMethodDecl *KeyFunc = getCurrentKeyFunction(RD);
8500          if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
8501            return true;
8502        }
8503      }
8504    }
8505
8506    GVALinkage Linkage = GetGVALinkageForFunction(FD);
8507
8508    // static, static inline, always_inline, and extern inline functions can
8509    // always be deferred.  Normal inline functions can be deferred in C99/C++.
8510    // Implicit template instantiations can also be deferred in C++.
8511    if (Linkage == GVA_Internal || Linkage == GVA_AvailableExternally ||
8512        Linkage == GVA_DiscardableODR)
8513      return false;
8514    return true;
8515  }
8516
8517  const VarDecl *VD = cast<VarDecl>(D);
8518  assert(VD->isFileVarDecl() && "Expected file scoped var");
8519
8520  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly &&
8521      !isMSStaticDataMemberInlineDefinition(VD))
8522    return false;
8523
8524  // Variables that can be needed in other TUs are required.
8525  GVALinkage L = GetGVALinkageForVariable(VD);
8526  if (L != GVA_Internal && L != GVA_AvailableExternally &&
8527      L != GVA_DiscardableODR)
8528    return true;
8529
8530  // Variables that have destruction with side-effects are required.
8531  if (VD->getType().isDestructedType())
8532    return true;
8533
8534  // Variables that have initialization with side-effects are required.
8535  if (VD->getInit() && VD->getInit()->HasSideEffects(*this) &&
8536      !VD->evaluateValue())
8537    return true;
8538
8539  return false;
8540}
8541
8542CallingConv ASTContext::getDefaultCallingConvention(bool IsVariadic,
8543                                                    bool IsCXXMethod) const {
8544  // Pass through to the C++ ABI object
8545  if (IsCXXMethod)
8546    return ABI->getDefaultMethodCallConv(IsVariadic);
8547
8548  if (LangOpts.MRTD && !IsVariadic) return CC_X86StdCall;
8549
8550  return Target->getDefaultCallingConv(TargetInfo::CCMT_Unknown);
8551}
8552
8553bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
8554  // Pass through to the C++ ABI object
8555  return ABI->isNearlyEmpty(RD);
8556}
8557
8558VTableContextBase *ASTContext::getVTableContext() {
8559  if (!VTContext.get()) {
8560    if (Target->getCXXABI().isMicrosoft())
8561      VTContext.reset(new MicrosoftVTableContext(*this));
8562    else
8563      VTContext.reset(new ItaniumVTableContext(*this));
8564  }
8565  return VTContext.get();
8566}
8567
8568MangleContext *ASTContext::createMangleContext() {
8569  switch (Target->getCXXABI().getKind()) {
8570  case TargetCXXABI::GenericAArch64:
8571  case TargetCXXABI::GenericItanium:
8572  case TargetCXXABI::GenericARM:
8573  case TargetCXXABI::GenericMIPS:
8574  case TargetCXXABI::iOS:
8575  case TargetCXXABI::iOS64:
8576  case TargetCXXABI::WebAssembly:
8577  case TargetCXXABI::WatchOS:
8578    return ItaniumMangleContext::create(*this, getDiagnostics());
8579  case TargetCXXABI::Microsoft:
8580    return MicrosoftMangleContext::create(*this, getDiagnostics());
8581  }
8582  llvm_unreachable("Unsupported ABI");
8583}
8584
8585CXXABI::~CXXABI() {}
8586
8587size_t ASTContext::getSideTableAllocatedMemory() const {
8588  return ASTRecordLayouts.getMemorySize() +
8589         llvm::capacity_in_bytes(ObjCLayouts) +
8590         llvm::capacity_in_bytes(KeyFunctions) +
8591         llvm::capacity_in_bytes(ObjCImpls) +
8592         llvm::capacity_in_bytes(BlockVarCopyInits) +
8593         llvm::capacity_in_bytes(DeclAttrs) +
8594         llvm::capacity_in_bytes(TemplateOrInstantiation) +
8595         llvm::capacity_in_bytes(InstantiatedFromUsingDecl) +
8596         llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl) +
8597         llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl) +
8598         llvm::capacity_in_bytes(OverriddenMethods) +
8599         llvm::capacity_in_bytes(Types) +
8600         llvm::capacity_in_bytes(VariableArrayTypes) +
8601         llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
8602}
8603
8604/// getIntTypeForBitwidth -
8605/// sets integer QualTy according to specified details:
8606/// bitwidth, signed/unsigned.
8607/// Returns empty type if there is no appropriate target types.
8608QualType ASTContext::getIntTypeForBitwidth(unsigned DestWidth,
8609                                           unsigned Signed) const {
8610  TargetInfo::IntType Ty = getTargetInfo().getIntTypeByWidth(DestWidth, Signed);
8611  CanQualType QualTy = getFromTargetType(Ty);
8612  if (!QualTy && DestWidth == 128)
8613    return Signed ? Int128Ty : UnsignedInt128Ty;
8614  return QualTy;
8615}
8616
8617/// getRealTypeForBitwidth -
8618/// sets floating point QualTy according to specified bitwidth.
8619/// Returns empty type if there is no appropriate target types.
8620QualType ASTContext::getRealTypeForBitwidth(unsigned DestWidth) const {
8621  TargetInfo::RealType Ty = getTargetInfo().getRealTypeByWidth(DestWidth);
8622  switch (Ty) {
8623  case TargetInfo::Float:
8624    return FloatTy;
8625  case TargetInfo::Double:
8626    return DoubleTy;
8627  case TargetInfo::LongDouble:
8628    return LongDoubleTy;
8629  case TargetInfo::NoFloat:
8630    return QualType();
8631  }
8632
8633  llvm_unreachable("Unhandled TargetInfo::RealType value");
8634}
8635
8636void ASTContext::setManglingNumber(const NamedDecl *ND, unsigned Number) {
8637  if (Number > 1)
8638    MangleNumbers[ND] = Number;
8639}
8640
8641unsigned ASTContext::getManglingNumber(const NamedDecl *ND) const {
8642  llvm::DenseMap<const NamedDecl *, unsigned>::const_iterator I =
8643    MangleNumbers.find(ND);
8644  return I != MangleNumbers.end() ? I->second : 1;
8645}
8646
8647void ASTContext::setStaticLocalNumber(const VarDecl *VD, unsigned Number) {
8648  if (Number > 1)
8649    StaticLocalNumbers[VD] = Number;
8650}
8651
8652unsigned ASTContext::getStaticLocalNumber(const VarDecl *VD) const {
8653  llvm::DenseMap<const VarDecl *, unsigned>::const_iterator I =
8654      StaticLocalNumbers.find(VD);
8655  return I != StaticLocalNumbers.end() ? I->second : 1;
8656}
8657
8658MangleNumberingContext &
8659ASTContext::getManglingNumberContext(const DeclContext *DC) {
8660  assert(LangOpts.CPlusPlus);  // We don't need mangling numbers for plain C.
8661  MangleNumberingContext *&MCtx = MangleNumberingContexts[DC];
8662  if (!MCtx)
8663    MCtx = createMangleNumberingContext();
8664  return *MCtx;
8665}
8666
8667MangleNumberingContext *ASTContext::createMangleNumberingContext() const {
8668  return ABI->createMangleNumberingContext();
8669}
8670
8671const CXXConstructorDecl *
8672ASTContext::getCopyConstructorForExceptionObject(CXXRecordDecl *RD) {
8673  return ABI->getCopyConstructorForExceptionObject(
8674      cast<CXXRecordDecl>(RD->getFirstDecl()));
8675}
8676
8677void ASTContext::addCopyConstructorForExceptionObject(CXXRecordDecl *RD,
8678                                                      CXXConstructorDecl *CD) {
8679  return ABI->addCopyConstructorForExceptionObject(
8680      cast<CXXRecordDecl>(RD->getFirstDecl()),
8681      cast<CXXConstructorDecl>(CD->getFirstDecl()));
8682}
8683
8684void ASTContext::addDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
8685                                                 unsigned ParmIdx, Expr *DAE) {
8686  ABI->addDefaultArgExprForConstructor(
8687      cast<CXXConstructorDecl>(CD->getFirstDecl()), ParmIdx, DAE);
8688}
8689
8690Expr *ASTContext::getDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
8691                                                  unsigned ParmIdx) {
8692  return ABI->getDefaultArgExprForConstructor(
8693      cast<CXXConstructorDecl>(CD->getFirstDecl()), ParmIdx);
8694}
8695
8696void ASTContext::addTypedefNameForUnnamedTagDecl(TagDecl *TD,
8697                                                 TypedefNameDecl *DD) {
8698  return ABI->addTypedefNameForUnnamedTagDecl(TD, DD);
8699}
8700
8701TypedefNameDecl *
8702ASTContext::getTypedefNameForUnnamedTagDecl(const TagDecl *TD) {
8703  return ABI->getTypedefNameForUnnamedTagDecl(TD);
8704}
8705
8706void ASTContext::addDeclaratorForUnnamedTagDecl(TagDecl *TD,
8707                                                DeclaratorDecl *DD) {
8708  return ABI->addDeclaratorForUnnamedTagDecl(TD, DD);
8709}
8710
8711DeclaratorDecl *ASTContext::getDeclaratorForUnnamedTagDecl(const TagDecl *TD) {
8712  return ABI->getDeclaratorForUnnamedTagDecl(TD);
8713}
8714
8715void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
8716  ParamIndices[D] = index;
8717}
8718
8719unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
8720  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
8721  assert(I != ParamIndices.end() &&
8722         "ParmIndices lacks entry set by ParmVarDecl");
8723  return I->second;
8724}
8725
8726APValue *
8727ASTContext::getMaterializedTemporaryValue(const MaterializeTemporaryExpr *E,
8728                                          bool MayCreate) {
8729  assert(E && E->getStorageDuration() == SD_Static &&
8730         "don't need to cache the computed value for this temporary");
8731  if (MayCreate) {
8732    APValue *&MTVI = MaterializedTemporaryValues[E];
8733    if (!MTVI)
8734      MTVI = new (*this) APValue;
8735    return MTVI;
8736  }
8737
8738  return MaterializedTemporaryValues.lookup(E);
8739}
8740
8741bool ASTContext::AtomicUsesUnsupportedLibcall(const AtomicExpr *E) const {
8742  const llvm::Triple &T = getTargetInfo().getTriple();
8743  if (!T.isOSDarwin())
8744    return false;
8745
8746  if (!(T.isiOS() && T.isOSVersionLT(7)) &&
8747      !(T.isMacOSX() && T.isOSVersionLT(10, 9)))
8748    return false;
8749
8750  QualType AtomicTy = E->getPtr()->getType()->getPointeeType();
8751  CharUnits sizeChars = getTypeSizeInChars(AtomicTy);
8752  uint64_t Size = sizeChars.getQuantity();
8753  CharUnits alignChars = getTypeAlignInChars(AtomicTy);
8754  unsigned Align = alignChars.getQuantity();
8755  unsigned MaxInlineWidthInBits = getTargetInfo().getMaxAtomicInlineWidth();
8756  return (Size != Align || toBits(sizeChars) > MaxInlineWidthInBits);
8757}
8758
8759namespace {
8760
8761ast_type_traits::DynTypedNode getSingleDynTypedNodeFromParentMap(
8762    ASTContext::ParentMapPointers::mapped_type U) {
8763  if (const auto *D = U.dyn_cast<const Decl *>())
8764    return ast_type_traits::DynTypedNode::create(*D);
8765  if (const auto *S = U.dyn_cast<const Stmt *>())
8766    return ast_type_traits::DynTypedNode::create(*S);
8767  return *U.get<ast_type_traits::DynTypedNode *>();
8768}
8769
8770/// Template specializations to abstract away from pointers and TypeLocs.
8771/// @{
8772template <typename T>
8773ast_type_traits::DynTypedNode createDynTypedNode(const T &Node) {
8774  return ast_type_traits::DynTypedNode::create(*Node);
8775}
8776template <>
8777ast_type_traits::DynTypedNode createDynTypedNode(const TypeLoc &Node) {
8778  return ast_type_traits::DynTypedNode::create(Node);
8779}
8780template <>
8781ast_type_traits::DynTypedNode
8782createDynTypedNode(const NestedNameSpecifierLoc &Node) {
8783  return ast_type_traits::DynTypedNode::create(Node);
8784}
8785/// @}
8786
8787  /// \brief A \c RecursiveASTVisitor that builds a map from nodes to their
8788  /// parents as defined by the \c RecursiveASTVisitor.
8789  ///
8790  /// Note that the relationship described here is purely in terms of AST
8791  /// traversal - there are other relationships (for example declaration context)
8792  /// in the AST that are better modeled by special matchers.
8793  ///
8794  /// FIXME: Currently only builds up the map using \c Stmt and \c Decl nodes.
8795  class ParentMapASTVisitor : public RecursiveASTVisitor<ParentMapASTVisitor> {
8796  public:
8797    /// \brief Builds and returns the translation unit's parent map.
8798    ///
8799    ///  The caller takes ownership of the returned \c ParentMap.
8800    static std::pair<ASTContext::ParentMapPointers *,
8801                     ASTContext::ParentMapOtherNodes *>
8802    buildMap(TranslationUnitDecl &TU) {
8803      ParentMapASTVisitor Visitor(new ASTContext::ParentMapPointers,
8804                                  new ASTContext::ParentMapOtherNodes);
8805      Visitor.TraverseDecl(&TU);
8806      return std::make_pair(Visitor.Parents, Visitor.OtherParents);
8807    }
8808
8809  private:
8810    typedef RecursiveASTVisitor<ParentMapASTVisitor> VisitorBase;
8811
8812    ParentMapASTVisitor(ASTContext::ParentMapPointers *Parents,
8813                        ASTContext::ParentMapOtherNodes *OtherParents)
8814        : Parents(Parents), OtherParents(OtherParents) {}
8815
8816    bool shouldVisitTemplateInstantiations() const {
8817      return true;
8818    }
8819    bool shouldVisitImplicitCode() const {
8820      return true;
8821    }
8822
8823    template <typename T, typename MapNodeTy, typename BaseTraverseFn,
8824              typename MapTy>
8825    bool TraverseNode(T Node, MapNodeTy MapNode,
8826                      BaseTraverseFn BaseTraverse, MapTy *Parents) {
8827      if (!Node)
8828        return true;
8829      if (ParentStack.size() > 0) {
8830        // FIXME: Currently we add the same parent multiple times, but only
8831        // when no memoization data is available for the type.
8832        // For example when we visit all subexpressions of template
8833        // instantiations; this is suboptimal, but benign: the only way to
8834        // visit those is with hasAncestor / hasParent, and those do not create
8835        // new matches.
8836        // The plan is to enable DynTypedNode to be storable in a map or hash
8837        // map. The main problem there is to implement hash functions /
8838        // comparison operators for all types that DynTypedNode supports that
8839        // do not have pointer identity.
8840        auto &NodeOrVector = (*Parents)[MapNode];
8841        if (NodeOrVector.isNull()) {
8842          if (const auto *D = ParentStack.back().get<Decl>())
8843            NodeOrVector = D;
8844          else if (const auto *S = ParentStack.back().get<Stmt>())
8845            NodeOrVector = S;
8846          else
8847            NodeOrVector =
8848                new ast_type_traits::DynTypedNode(ParentStack.back());
8849        } else {
8850          if (!NodeOrVector.template is<ASTContext::ParentVector *>()) {
8851            auto *Vector = new ASTContext::ParentVector(
8852                1, getSingleDynTypedNodeFromParentMap(NodeOrVector));
8853            if (auto *Node =
8854                    NodeOrVector
8855                        .template dyn_cast<ast_type_traits::DynTypedNode *>())
8856              delete Node;
8857            NodeOrVector = Vector;
8858          }
8859
8860          auto *Vector =
8861              NodeOrVector.template get<ASTContext::ParentVector *>();
8862          // Skip duplicates for types that have memoization data.
8863          // We must check that the type has memoization data before calling
8864          // std::find() because DynTypedNode::operator== can't compare all
8865          // types.
8866          bool Found = ParentStack.back().getMemoizationData() &&
8867                       std::find(Vector->begin(), Vector->end(),
8868                                 ParentStack.back()) != Vector->end();
8869          if (!Found)
8870            Vector->push_back(ParentStack.back());
8871        }
8872      }
8873      ParentStack.push_back(createDynTypedNode(Node));
8874      bool Result = BaseTraverse();
8875      ParentStack.pop_back();
8876      return Result;
8877    }
8878
8879    bool TraverseDecl(Decl *DeclNode) {
8880      return TraverseNode(DeclNode, DeclNode,
8881                          [&] { return VisitorBase::TraverseDecl(DeclNode); },
8882                          Parents);
8883    }
8884
8885    bool TraverseStmt(Stmt *StmtNode) {
8886      return TraverseNode(StmtNode, StmtNode,
8887                          [&] { return VisitorBase::TraverseStmt(StmtNode); },
8888                          Parents);
8889    }
8890
8891    bool TraverseTypeLoc(TypeLoc TypeLocNode) {
8892      return TraverseNode(
8893          TypeLocNode, ast_type_traits::DynTypedNode::create(TypeLocNode),
8894          [&] { return VisitorBase::TraverseTypeLoc(TypeLocNode); },
8895          OtherParents);
8896    }
8897
8898    bool TraverseNestedNameSpecifierLoc(NestedNameSpecifierLoc NNSLocNode) {
8899      return TraverseNode(
8900          NNSLocNode, ast_type_traits::DynTypedNode::create(NNSLocNode),
8901          [&] {
8902            return VisitorBase::TraverseNestedNameSpecifierLoc(NNSLocNode);
8903          },
8904          OtherParents);
8905    }
8906
8907    ASTContext::ParentMapPointers *Parents;
8908    ASTContext::ParentMapOtherNodes *OtherParents;
8909    llvm::SmallVector<ast_type_traits::DynTypedNode, 16> ParentStack;
8910
8911    friend class RecursiveASTVisitor<ParentMapASTVisitor>;
8912  };
8913
8914} // anonymous namespace
8915
8916template <typename NodeTy, typename MapTy>
8917static ASTContext::DynTypedNodeList getDynNodeFromMap(const NodeTy &Node,
8918                                                      const MapTy &Map) {
8919  auto I = Map.find(Node);
8920  if (I == Map.end()) {
8921    return llvm::ArrayRef<ast_type_traits::DynTypedNode>();
8922  }
8923  if (auto *V = I->second.template dyn_cast<ASTContext::ParentVector *>()) {
8924    return llvm::makeArrayRef(*V);
8925  }
8926  return getSingleDynTypedNodeFromParentMap(I->second);
8927}
8928
8929ASTContext::DynTypedNodeList
8930ASTContext::getParents(const ast_type_traits::DynTypedNode &Node) {
8931  if (!PointerParents) {
8932    // We always need to run over the whole translation unit, as
8933    // hasAncestor can escape any subtree.
8934    auto Maps = ParentMapASTVisitor::buildMap(*getTranslationUnitDecl());
8935    PointerParents.reset(Maps.first);
8936    OtherParents.reset(Maps.second);
8937  }
8938  if (Node.getNodeKind().hasPointerIdentity())
8939    return getDynNodeFromMap(Node.getMemoizationData(), *PointerParents);
8940  return getDynNodeFromMap(Node, *OtherParents);
8941}
8942
8943bool
8944ASTContext::ObjCMethodsAreEqual(const ObjCMethodDecl *MethodDecl,
8945                                const ObjCMethodDecl *MethodImpl) {
8946  // No point trying to match an unavailable/deprecated mothod.
8947  if (MethodDecl->hasAttr<UnavailableAttr>()
8948      || MethodDecl->hasAttr<DeprecatedAttr>())
8949    return false;
8950  if (MethodDecl->getObjCDeclQualifier() !=
8951      MethodImpl->getObjCDeclQualifier())
8952    return false;
8953  if (!hasSameType(MethodDecl->getReturnType(), MethodImpl->getReturnType()))
8954    return false;
8955
8956  if (MethodDecl->param_size() != MethodImpl->param_size())
8957    return false;
8958
8959  for (ObjCMethodDecl::param_const_iterator IM = MethodImpl->param_begin(),
8960       IF = MethodDecl->param_begin(), EM = MethodImpl->param_end(),
8961       EF = MethodDecl->param_end();
8962       IM != EM && IF != EF; ++IM, ++IF) {
8963    const ParmVarDecl *DeclVar = (*IF);
8964    const ParmVarDecl *ImplVar = (*IM);
8965    if (ImplVar->getObjCDeclQualifier() != DeclVar->getObjCDeclQualifier())
8966      return false;
8967    if (!hasSameType(DeclVar->getType(), ImplVar->getType()))
8968      return false;
8969  }
8970  return (MethodDecl->isVariadic() == MethodImpl->isVariadic());
8971
8972}
8973
8974// Explicitly instantiate this in case a Redeclarable<T> is used from a TU that
8975// doesn't include ASTContext.h
8976template
8977clang::LazyGenerationalUpdatePtr<
8978    const Decl *, Decl *, &ExternalASTSource::CompleteRedeclChain>::ValueType
8979clang::LazyGenerationalUpdatePtr<
8980    const Decl *, Decl *, &ExternalASTSource::CompleteRedeclChain>::makeValue(
8981        const clang::ASTContext &Ctx, Decl *Value);
8982