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, Float128Rank
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,
637                                                ExpandedTInfos);
638      } else {
639        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
640                                                SourceLocation(),
641                                                SourceLocation(),
642                                                NTTP->getDepth(),
643                                                NTTP->getPosition(), nullptr,
644                                                T,
645                                                NTTP->isParameterPack(),
646                                                TInfo);
647      }
648      CanonParams.push_back(Param);
649
650    } else
651      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
652                                           cast<TemplateTemplateParmDecl>(*P)));
653  }
654
655  TemplateTemplateParmDecl *CanonTTP
656    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
657                                       SourceLocation(), TTP->getDepth(),
658                                       TTP->getPosition(),
659                                       TTP->isParameterPack(),
660                                       nullptr,
661                         TemplateParameterList::Create(*this, SourceLocation(),
662                                                       SourceLocation(),
663                                                       CanonParams,
664                                                       SourceLocation()));
665
666  // Get the new insert position for the node we care about.
667  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
668  assert(!Canonical && "Shouldn't be in the map!");
669  (void)Canonical;
670
671  // Create the canonical template template parameter entry.
672  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
673  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
674  return CanonTTP;
675}
676
677CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
678  if (!LangOpts.CPlusPlus) return nullptr;
679
680  switch (T.getCXXABI().getKind()) {
681  case TargetCXXABI::GenericARM: // Same as Itanium at this level
682  case TargetCXXABI::iOS:
683  case TargetCXXABI::iOS64:
684  case TargetCXXABI::WatchOS:
685  case TargetCXXABI::GenericAArch64:
686  case TargetCXXABI::GenericMIPS:
687  case TargetCXXABI::GenericItanium:
688  case TargetCXXABI::WebAssembly:
689    return CreateItaniumCXXABI(*this);
690  case TargetCXXABI::Microsoft:
691    return CreateMicrosoftCXXABI(*this);
692  }
693  llvm_unreachable("Invalid CXXABI type!");
694}
695
696static const LangAS::Map *getAddressSpaceMap(const TargetInfo &T,
697                                             const LangOptions &LOpts) {
698  if (LOpts.FakeAddressSpaceMap) {
699    // The fake address space map must have a distinct entry for each
700    // language-specific address space.
701    static const unsigned FakeAddrSpaceMap[] = {
702      1, // opencl_global
703      2, // opencl_local
704      3, // opencl_constant
705      4, // opencl_generic
706      5, // cuda_device
707      6, // cuda_constant
708      7  // cuda_shared
709    };
710    return &FakeAddrSpaceMap;
711  } else {
712    return &T.getAddressSpaceMap();
713  }
714}
715
716static bool isAddrSpaceMapManglingEnabled(const TargetInfo &TI,
717                                          const LangOptions &LangOpts) {
718  switch (LangOpts.getAddressSpaceMapMangling()) {
719  case LangOptions::ASMM_Target:
720    return TI.useAddressSpaceMapMangling();
721  case LangOptions::ASMM_On:
722    return true;
723  case LangOptions::ASMM_Off:
724    return false;
725  }
726  llvm_unreachable("getAddressSpaceMapMangling() doesn't cover anything.");
727}
728
729ASTContext::ASTContext(LangOptions &LOpts, SourceManager &SM,
730                       IdentifierTable &idents, SelectorTable &sels,
731                       Builtin::Context &builtins)
732    : FunctionProtoTypes(this_()), TemplateSpecializationTypes(this_()),
733      DependentTemplateSpecializationTypes(this_()),
734      SubstTemplateTemplateParmPacks(this_()),
735      GlobalNestedNameSpecifier(nullptr), Int128Decl(nullptr),
736      UInt128Decl(nullptr), BuiltinVaListDecl(nullptr),
737      BuiltinMSVaListDecl(nullptr), ObjCIdDecl(nullptr), ObjCSelDecl(nullptr),
738      ObjCClassDecl(nullptr), ObjCProtocolClassDecl(nullptr), BOOLDecl(nullptr),
739      CFConstantStringTagDecl(nullptr), CFConstantStringTypeDecl(nullptr),
740      ObjCInstanceTypeDecl(nullptr), FILEDecl(nullptr), jmp_bufDecl(nullptr),
741      sigjmp_bufDecl(nullptr), ucontext_tDecl(nullptr),
742      BlockDescriptorType(nullptr), BlockDescriptorExtendedType(nullptr),
743      cudaConfigureCallDecl(nullptr), FirstLocalImport(), LastLocalImport(),
744      ExternCContext(nullptr), MakeIntegerSeqDecl(nullptr),
745      TypePackElementDecl(nullptr), SourceMgr(SM), LangOpts(LOpts),
746      SanitizerBL(new SanitizerBlacklist(LangOpts.SanitizerBlacklistFiles, SM)),
747      AddrSpaceMap(nullptr), Target(nullptr), AuxTarget(nullptr),
748      PrintingPolicy(LOpts), Idents(idents), Selectors(sels),
749      BuiltinInfo(builtins), DeclarationNames(*this), ExternalSource(nullptr),
750      Listener(nullptr), Comments(SM), CommentsLoaded(false),
751      CommentCommandTraits(BumpAlloc, LOpts.CommentOpts), LastSDM(nullptr, 0) {
752  TUDecl = TranslationUnitDecl::Create(*this);
753}
754
755ASTContext::~ASTContext() {
756  ReleaseParentMapEntries();
757
758  // Release the DenseMaps associated with DeclContext objects.
759  // FIXME: Is this the ideal solution?
760  ReleaseDeclContextMaps();
761
762  // Call all of the deallocation functions on all of their targets.
763  for (auto &Pair : Deallocations)
764    (Pair.first)(Pair.second);
765
766  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
767  // because they can contain DenseMaps.
768  for (llvm::DenseMap<const ObjCContainerDecl*,
769       const ASTRecordLayout*>::iterator
770       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
771    // Increment in loop to prevent using deallocated memory.
772    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
773      R->Destroy(*this);
774
775  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
776       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
777    // Increment in loop to prevent using deallocated memory.
778    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
779      R->Destroy(*this);
780  }
781
782  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
783                                                    AEnd = DeclAttrs.end();
784       A != AEnd; ++A)
785    A->second->~AttrVec();
786
787  for (std::pair<const MaterializeTemporaryExpr *, APValue *> &MTVPair :
788       MaterializedTemporaryValues)
789    MTVPair.second->~APValue();
790
791  llvm::DeleteContainerSeconds(MangleNumberingContexts);
792}
793
794void ASTContext::ReleaseParentMapEntries() {
795  if (!PointerParents) return;
796  for (const auto &Entry : *PointerParents) {
797    if (Entry.second.is<ast_type_traits::DynTypedNode *>()) {
798      delete Entry.second.get<ast_type_traits::DynTypedNode *>();
799    } else if (Entry.second.is<ParentVector *>()) {
800      delete Entry.second.get<ParentVector *>();
801    }
802  }
803  for (const auto &Entry : *OtherParents) {
804    if (Entry.second.is<ast_type_traits::DynTypedNode *>()) {
805      delete Entry.second.get<ast_type_traits::DynTypedNode *>();
806    } else if (Entry.second.is<ParentVector *>()) {
807      delete Entry.second.get<ParentVector *>();
808    }
809  }
810}
811
812void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
813  Deallocations.push_back({Callback, Data});
814}
815
816void
817ASTContext::setExternalSource(IntrusiveRefCntPtr<ExternalASTSource> Source) {
818  ExternalSource = std::move(Source);
819}
820
821void ASTContext::PrintStats() const {
822  llvm::errs() << "\n*** AST Context Stats:\n";
823  llvm::errs() << "  " << Types.size() << " types total.\n";
824
825  unsigned counts[] = {
826#define TYPE(Name, Parent) 0,
827#define ABSTRACT_TYPE(Name, Parent)
828#include "clang/AST/TypeNodes.def"
829    0 // Extra
830  };
831
832  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
833    Type *T = Types[i];
834    counts[(unsigned)T->getTypeClass()]++;
835  }
836
837  unsigned Idx = 0;
838  unsigned TotalBytes = 0;
839#define TYPE(Name, Parent)                                              \
840  if (counts[Idx])                                                      \
841    llvm::errs() << "    " << counts[Idx] << " " << #Name               \
842                 << " types\n";                                         \
843  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
844  ++Idx;
845#define ABSTRACT_TYPE(Name, Parent)
846#include "clang/AST/TypeNodes.def"
847
848  llvm::errs() << "Total bytes = " << TotalBytes << "\n";
849
850  // Implicit special member functions.
851  llvm::errs() << NumImplicitDefaultConstructorsDeclared << "/"
852               << NumImplicitDefaultConstructors
853               << " implicit default constructors created\n";
854  llvm::errs() << NumImplicitCopyConstructorsDeclared << "/"
855               << NumImplicitCopyConstructors
856               << " implicit copy constructors created\n";
857  if (getLangOpts().CPlusPlus)
858    llvm::errs() << NumImplicitMoveConstructorsDeclared << "/"
859                 << NumImplicitMoveConstructors
860                 << " implicit move constructors created\n";
861  llvm::errs() << NumImplicitCopyAssignmentOperatorsDeclared << "/"
862               << NumImplicitCopyAssignmentOperators
863               << " implicit copy assignment operators created\n";
864  if (getLangOpts().CPlusPlus)
865    llvm::errs() << NumImplicitMoveAssignmentOperatorsDeclared << "/"
866                 << NumImplicitMoveAssignmentOperators
867                 << " implicit move assignment operators created\n";
868  llvm::errs() << NumImplicitDestructorsDeclared << "/"
869               << NumImplicitDestructors
870               << " implicit destructors created\n";
871
872  if (ExternalSource) {
873    llvm::errs() << "\n";
874    ExternalSource->PrintStats();
875  }
876
877  BumpAlloc.PrintStats();
878}
879
880void ASTContext::mergeDefinitionIntoModule(NamedDecl *ND, Module *M,
881                                           bool NotifyListeners) {
882  if (NotifyListeners)
883    if (auto *Listener = getASTMutationListener())
884      Listener->RedefinedHiddenDefinition(ND, M);
885
886  if (getLangOpts().ModulesLocalVisibility)
887    MergedDefModules[ND].push_back(M);
888  else
889    ND->setHidden(false);
890}
891
892void ASTContext::deduplicateMergedDefinitonsFor(NamedDecl *ND) {
893  auto It = MergedDefModules.find(ND);
894  if (It == MergedDefModules.end())
895    return;
896
897  auto &Merged = It->second;
898  llvm::DenseSet<Module*> Found;
899  for (Module *&M : Merged)
900    if (!Found.insert(M).second)
901      M = nullptr;
902  Merged.erase(std::remove(Merged.begin(), Merged.end(), nullptr), Merged.end());
903}
904
905ExternCContextDecl *ASTContext::getExternCContextDecl() const {
906  if (!ExternCContext)
907    ExternCContext = ExternCContextDecl::Create(*this, getTranslationUnitDecl());
908
909  return ExternCContext;
910}
911
912BuiltinTemplateDecl *
913ASTContext::buildBuiltinTemplateDecl(BuiltinTemplateKind BTK,
914                                     const IdentifierInfo *II) const {
915  auto *BuiltinTemplate = BuiltinTemplateDecl::Create(*this, TUDecl, II, BTK);
916  BuiltinTemplate->setImplicit();
917  TUDecl->addDecl(BuiltinTemplate);
918
919  return BuiltinTemplate;
920}
921
922BuiltinTemplateDecl *
923ASTContext::getMakeIntegerSeqDecl() const {
924  if (!MakeIntegerSeqDecl)
925    MakeIntegerSeqDecl = buildBuiltinTemplateDecl(BTK__make_integer_seq,
926                                                  getMakeIntegerSeqName());
927  return MakeIntegerSeqDecl;
928}
929
930BuiltinTemplateDecl *
931ASTContext::getTypePackElementDecl() const {
932  if (!TypePackElementDecl)
933    TypePackElementDecl = buildBuiltinTemplateDecl(BTK__type_pack_element,
934                                                   getTypePackElementName());
935  return TypePackElementDecl;
936}
937
938RecordDecl *ASTContext::buildImplicitRecord(StringRef Name,
939                                            RecordDecl::TagKind TK) const {
940  SourceLocation Loc;
941  RecordDecl *NewDecl;
942  if (getLangOpts().CPlusPlus)
943    NewDecl = CXXRecordDecl::Create(*this, TK, getTranslationUnitDecl(), Loc,
944                                    Loc, &Idents.get(Name));
945  else
946    NewDecl = RecordDecl::Create(*this, TK, getTranslationUnitDecl(), Loc, Loc,
947                                 &Idents.get(Name));
948  NewDecl->setImplicit();
949  NewDecl->addAttr(TypeVisibilityAttr::CreateImplicit(
950      const_cast<ASTContext &>(*this), TypeVisibilityAttr::Default));
951  return NewDecl;
952}
953
954TypedefDecl *ASTContext::buildImplicitTypedef(QualType T,
955                                              StringRef Name) const {
956  TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
957  TypedefDecl *NewDecl = TypedefDecl::Create(
958      const_cast<ASTContext &>(*this), getTranslationUnitDecl(),
959      SourceLocation(), SourceLocation(), &Idents.get(Name), TInfo);
960  NewDecl->setImplicit();
961  return NewDecl;
962}
963
964TypedefDecl *ASTContext::getInt128Decl() const {
965  if (!Int128Decl)
966    Int128Decl = buildImplicitTypedef(Int128Ty, "__int128_t");
967  return Int128Decl;
968}
969
970TypedefDecl *ASTContext::getUInt128Decl() const {
971  if (!UInt128Decl)
972    UInt128Decl = buildImplicitTypedef(UnsignedInt128Ty, "__uint128_t");
973  return UInt128Decl;
974}
975
976void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
977  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
978  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
979  Types.push_back(Ty);
980}
981
982void ASTContext::InitBuiltinTypes(const TargetInfo &Target,
983                                  const TargetInfo *AuxTarget) {
984  assert((!this->Target || this->Target == &Target) &&
985         "Incorrect target reinitialization");
986  assert(VoidTy.isNull() && "Context reinitialized?");
987
988  this->Target = &Target;
989  this->AuxTarget = AuxTarget;
990
991  ABI.reset(createCXXABI(Target));
992  AddrSpaceMap = getAddressSpaceMap(Target, LangOpts);
993  AddrSpaceMapMangling = isAddrSpaceMapManglingEnabled(Target, LangOpts);
994
995  // C99 6.2.5p19.
996  InitBuiltinType(VoidTy,              BuiltinType::Void);
997
998  // C99 6.2.5p2.
999  InitBuiltinType(BoolTy,              BuiltinType::Bool);
1000  // C99 6.2.5p3.
1001  if (LangOpts.CharIsSigned)
1002    InitBuiltinType(CharTy,            BuiltinType::Char_S);
1003  else
1004    InitBuiltinType(CharTy,            BuiltinType::Char_U);
1005  // C99 6.2.5p4.
1006  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
1007  InitBuiltinType(ShortTy,             BuiltinType::Short);
1008  InitBuiltinType(IntTy,               BuiltinType::Int);
1009  InitBuiltinType(LongTy,              BuiltinType::Long);
1010  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
1011
1012  // C99 6.2.5p6.
1013  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
1014  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
1015  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
1016  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
1017  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
1018
1019  // C99 6.2.5p10.
1020  InitBuiltinType(FloatTy,             BuiltinType::Float);
1021  InitBuiltinType(DoubleTy,            BuiltinType::Double);
1022  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
1023
1024  // GNU extension, __float128 for IEEE quadruple precision
1025  InitBuiltinType(Float128Ty,          BuiltinType::Float128);
1026
1027  // GNU extension, 128-bit integers.
1028  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
1029  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
1030
1031  // C++ 3.9.1p5
1032  if (TargetInfo::isTypeSigned(Target.getWCharType()))
1033    InitBuiltinType(WCharTy,           BuiltinType::WChar_S);
1034  else  // -fshort-wchar makes wchar_t be unsigned.
1035    InitBuiltinType(WCharTy,           BuiltinType::WChar_U);
1036  if (LangOpts.CPlusPlus && LangOpts.WChar)
1037    WideCharTy = WCharTy;
1038  else {
1039    // C99 (or C++ using -fno-wchar).
1040    WideCharTy = getFromTargetType(Target.getWCharType());
1041  }
1042
1043  WIntTy = getFromTargetType(Target.getWIntType());
1044
1045  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
1046    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
1047  else // C99
1048    Char16Ty = getFromTargetType(Target.getChar16Type());
1049
1050  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
1051    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
1052  else // C99
1053    Char32Ty = getFromTargetType(Target.getChar32Type());
1054
1055  // Placeholder type for type-dependent expressions whose type is
1056  // completely unknown. No code should ever check a type against
1057  // DependentTy and users should never see it; however, it is here to
1058  // help diagnose failures to properly check for type-dependent
1059  // expressions.
1060  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
1061
1062  // Placeholder type for functions.
1063  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
1064
1065  // Placeholder type for bound members.
1066  InitBuiltinType(BoundMemberTy,       BuiltinType::BoundMember);
1067
1068  // Placeholder type for pseudo-objects.
1069  InitBuiltinType(PseudoObjectTy,      BuiltinType::PseudoObject);
1070
1071  // "any" type; useful for debugger-like clients.
1072  InitBuiltinType(UnknownAnyTy,        BuiltinType::UnknownAny);
1073
1074  // Placeholder type for unbridged ARC casts.
1075  InitBuiltinType(ARCUnbridgedCastTy,  BuiltinType::ARCUnbridgedCast);
1076
1077  // Placeholder type for builtin functions.
1078  InitBuiltinType(BuiltinFnTy,  BuiltinType::BuiltinFn);
1079
1080  // Placeholder type for OMP array sections.
1081  if (LangOpts.OpenMP)
1082    InitBuiltinType(OMPArraySectionTy, BuiltinType::OMPArraySection);
1083
1084  // C99 6.2.5p11.
1085  FloatComplexTy      = getComplexType(FloatTy);
1086  DoubleComplexTy     = getComplexType(DoubleTy);
1087  LongDoubleComplexTy = getComplexType(LongDoubleTy);
1088  Float128ComplexTy   = getComplexType(Float128Ty);
1089
1090  // Builtin types for 'id', 'Class', and 'SEL'.
1091  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
1092  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
1093  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
1094
1095  if (LangOpts.OpenCL) {
1096#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
1097    InitBuiltinType(SingletonId, BuiltinType::Id);
1098#include "clang/Basic/OpenCLImageTypes.def"
1099
1100    InitBuiltinType(OCLSamplerTy, BuiltinType::OCLSampler);
1101    InitBuiltinType(OCLEventTy, BuiltinType::OCLEvent);
1102    InitBuiltinType(OCLClkEventTy, BuiltinType::OCLClkEvent);
1103    InitBuiltinType(OCLQueueTy, BuiltinType::OCLQueue);
1104    InitBuiltinType(OCLNDRangeTy, BuiltinType::OCLNDRange);
1105    InitBuiltinType(OCLReserveIDTy, BuiltinType::OCLReserveID);
1106  }
1107
1108  // Builtin type for __objc_yes and __objc_no
1109  ObjCBuiltinBoolTy = (Target.useSignedCharForObjCBool() ?
1110                       SignedCharTy : BoolTy);
1111
1112  ObjCConstantStringType = QualType();
1113
1114  ObjCSuperType = QualType();
1115
1116  // void * type
1117  VoidPtrTy = getPointerType(VoidTy);
1118
1119  // nullptr type (C++0x 2.14.7)
1120  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
1121
1122  // half type (OpenCL 6.1.1.1) / ARM NEON __fp16
1123  InitBuiltinType(HalfTy, BuiltinType::Half);
1124
1125  // Builtin type used to help define __builtin_va_list.
1126  VaListTagDecl = nullptr;
1127}
1128
1129DiagnosticsEngine &ASTContext::getDiagnostics() const {
1130  return SourceMgr.getDiagnostics();
1131}
1132
1133AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
1134  AttrVec *&Result = DeclAttrs[D];
1135  if (!Result) {
1136    void *Mem = Allocate(sizeof(AttrVec));
1137    Result = new (Mem) AttrVec;
1138  }
1139
1140  return *Result;
1141}
1142
1143/// \brief Erase the attributes corresponding to the given declaration.
1144void ASTContext::eraseDeclAttrs(const Decl *D) {
1145  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
1146  if (Pos != DeclAttrs.end()) {
1147    Pos->second->~AttrVec();
1148    DeclAttrs.erase(Pos);
1149  }
1150}
1151
1152// FIXME: Remove ?
1153MemberSpecializationInfo *
1154ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
1155  assert(Var->isStaticDataMember() && "Not a static data member");
1156  return getTemplateOrSpecializationInfo(Var)
1157      .dyn_cast<MemberSpecializationInfo *>();
1158}
1159
1160ASTContext::TemplateOrSpecializationInfo
1161ASTContext::getTemplateOrSpecializationInfo(const VarDecl *Var) {
1162  llvm::DenseMap<const VarDecl *, TemplateOrSpecializationInfo>::iterator Pos =
1163      TemplateOrInstantiation.find(Var);
1164  if (Pos == TemplateOrInstantiation.end())
1165    return TemplateOrSpecializationInfo();
1166
1167  return Pos->second;
1168}
1169
1170void
1171ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
1172                                                TemplateSpecializationKind TSK,
1173                                          SourceLocation PointOfInstantiation) {
1174  assert(Inst->isStaticDataMember() && "Not a static data member");
1175  assert(Tmpl->isStaticDataMember() && "Not a static data member");
1176  setTemplateOrSpecializationInfo(Inst, new (*this) MemberSpecializationInfo(
1177                                            Tmpl, TSK, PointOfInstantiation));
1178}
1179
1180void
1181ASTContext::setTemplateOrSpecializationInfo(VarDecl *Inst,
1182                                            TemplateOrSpecializationInfo TSI) {
1183  assert(!TemplateOrInstantiation[Inst] &&
1184         "Already noted what the variable was instantiated from");
1185  TemplateOrInstantiation[Inst] = TSI;
1186}
1187
1188FunctionDecl *ASTContext::getClassScopeSpecializationPattern(
1189                                                     const FunctionDecl *FD){
1190  assert(FD && "Specialization is 0");
1191  llvm::DenseMap<const FunctionDecl*, FunctionDecl *>::const_iterator Pos
1192    = ClassScopeSpecializationPattern.find(FD);
1193  if (Pos == ClassScopeSpecializationPattern.end())
1194    return nullptr;
1195
1196  return Pos->second;
1197}
1198
1199void ASTContext::setClassScopeSpecializationPattern(FunctionDecl *FD,
1200                                        FunctionDecl *Pattern) {
1201  assert(FD && "Specialization is 0");
1202  assert(Pattern && "Class scope specialization pattern is 0");
1203  ClassScopeSpecializationPattern[FD] = Pattern;
1204}
1205
1206NamedDecl *
1207ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
1208  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
1209    = InstantiatedFromUsingDecl.find(UUD);
1210  if (Pos == InstantiatedFromUsingDecl.end())
1211    return nullptr;
1212
1213  return Pos->second;
1214}
1215
1216void
1217ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
1218  assert((isa<UsingDecl>(Pattern) ||
1219          isa<UnresolvedUsingValueDecl>(Pattern) ||
1220          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
1221         "pattern decl is not a using decl");
1222  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
1223  InstantiatedFromUsingDecl[Inst] = Pattern;
1224}
1225
1226UsingShadowDecl *
1227ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
1228  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
1229    = InstantiatedFromUsingShadowDecl.find(Inst);
1230  if (Pos == InstantiatedFromUsingShadowDecl.end())
1231    return nullptr;
1232
1233  return Pos->second;
1234}
1235
1236void
1237ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
1238                                               UsingShadowDecl *Pattern) {
1239  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
1240  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
1241}
1242
1243FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
1244  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
1245    = InstantiatedFromUnnamedFieldDecl.find(Field);
1246  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
1247    return nullptr;
1248
1249  return Pos->second;
1250}
1251
1252void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
1253                                                     FieldDecl *Tmpl) {
1254  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
1255  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
1256  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
1257         "Already noted what unnamed field was instantiated from");
1258
1259  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
1260}
1261
1262ASTContext::overridden_cxx_method_iterator
1263ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
1264  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos =
1265      OverriddenMethods.find(Method->getCanonicalDecl());
1266  if (Pos == OverriddenMethods.end())
1267    return nullptr;
1268  return Pos->second.begin();
1269}
1270
1271ASTContext::overridden_cxx_method_iterator
1272ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
1273  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos =
1274      OverriddenMethods.find(Method->getCanonicalDecl());
1275  if (Pos == OverriddenMethods.end())
1276    return nullptr;
1277  return Pos->second.end();
1278}
1279
1280unsigned
1281ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
1282  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos =
1283      OverriddenMethods.find(Method->getCanonicalDecl());
1284  if (Pos == OverriddenMethods.end())
1285    return 0;
1286  return Pos->second.size();
1287}
1288
1289ASTContext::overridden_method_range
1290ASTContext::overridden_methods(const CXXMethodDecl *Method) const {
1291  return overridden_method_range(overridden_methods_begin(Method),
1292                                 overridden_methods_end(Method));
1293}
1294
1295void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
1296                                     const CXXMethodDecl *Overridden) {
1297  assert(Method->isCanonicalDecl() && Overridden->isCanonicalDecl());
1298  OverriddenMethods[Method].push_back(Overridden);
1299}
1300
1301void ASTContext::getOverriddenMethods(
1302                      const NamedDecl *D,
1303                      SmallVectorImpl<const NamedDecl *> &Overridden) const {
1304  assert(D);
1305
1306  if (const CXXMethodDecl *CXXMethod = dyn_cast<CXXMethodDecl>(D)) {
1307    Overridden.append(overridden_methods_begin(CXXMethod),
1308                      overridden_methods_end(CXXMethod));
1309    return;
1310  }
1311
1312  const ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(D);
1313  if (!Method)
1314    return;
1315
1316  SmallVector<const ObjCMethodDecl *, 8> OverDecls;
1317  Method->getOverriddenMethods(OverDecls);
1318  Overridden.append(OverDecls.begin(), OverDecls.end());
1319}
1320
1321void ASTContext::addedLocalImportDecl(ImportDecl *Import) {
1322  assert(!Import->NextLocalImport && "Import declaration already in the chain");
1323  assert(!Import->isFromASTFile() && "Non-local import declaration");
1324  if (!FirstLocalImport) {
1325    FirstLocalImport = Import;
1326    LastLocalImport = Import;
1327    return;
1328  }
1329
1330  LastLocalImport->NextLocalImport = Import;
1331  LastLocalImport = Import;
1332}
1333
1334//===----------------------------------------------------------------------===//
1335//                         Type Sizing and Analysis
1336//===----------------------------------------------------------------------===//
1337
1338/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
1339/// scalar floating point type.
1340const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
1341  const BuiltinType *BT = T->getAs<BuiltinType>();
1342  assert(BT && "Not a floating point type!");
1343  switch (BT->getKind()) {
1344  default: llvm_unreachable("Not a floating point type!");
1345  case BuiltinType::Half:       return Target->getHalfFormat();
1346  case BuiltinType::Float:      return Target->getFloatFormat();
1347  case BuiltinType::Double:     return Target->getDoubleFormat();
1348  case BuiltinType::LongDouble: return Target->getLongDoubleFormat();
1349  case BuiltinType::Float128:   return Target->getFloat128Format();
1350  }
1351}
1352
1353CharUnits ASTContext::getDeclAlign(const Decl *D, bool ForAlignof) const {
1354  unsigned Align = Target->getCharWidth();
1355
1356  bool UseAlignAttrOnly = false;
1357  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
1358    Align = AlignFromAttr;
1359
1360    // __attribute__((aligned)) can increase or decrease alignment
1361    // *except* on a struct or struct member, where it only increases
1362    // alignment unless 'packed' is also specified.
1363    //
1364    // It is an error for alignas to decrease alignment, so we can
1365    // ignore that possibility;  Sema should diagnose it.
1366    if (isa<FieldDecl>(D)) {
1367      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
1368        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1369    } else {
1370      UseAlignAttrOnly = true;
1371    }
1372  }
1373  else if (isa<FieldDecl>(D))
1374      UseAlignAttrOnly =
1375        D->hasAttr<PackedAttr>() ||
1376        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1377
1378  // If we're using the align attribute only, just ignore everything
1379  // else about the declaration and its type.
1380  if (UseAlignAttrOnly) {
1381    // do nothing
1382
1383  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
1384    QualType T = VD->getType();
1385    if (const ReferenceType *RT = T->getAs<ReferenceType>()) {
1386      if (ForAlignof)
1387        T = RT->getPointeeType();
1388      else
1389        T = getPointerType(RT->getPointeeType());
1390    }
1391    QualType BaseT = getBaseElementType(T);
1392    if (!BaseT->isIncompleteType() && !T->isFunctionType()) {
1393      // Adjust alignments of declarations with array type by the
1394      // large-array alignment on the target.
1395      if (const ArrayType *arrayType = getAsArrayType(T)) {
1396        unsigned MinWidth = Target->getLargeArrayMinWidth();
1397        if (!ForAlignof && MinWidth) {
1398          if (isa<VariableArrayType>(arrayType))
1399            Align = std::max(Align, Target->getLargeArrayAlign());
1400          else if (isa<ConstantArrayType>(arrayType) &&
1401                   MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
1402            Align = std::max(Align, Target->getLargeArrayAlign());
1403        }
1404      }
1405      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
1406      if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1407        if (VD->hasGlobalStorage() && !ForAlignof)
1408          Align = std::max(Align, getTargetInfo().getMinGlobalAlign());
1409      }
1410    }
1411
1412    // Fields can be subject to extra alignment constraints, like if
1413    // the field is packed, the struct is packed, or the struct has a
1414    // a max-field-alignment constraint (#pragma pack).  So calculate
1415    // the actual alignment of the field within the struct, and then
1416    // (as we're expected to) constrain that by the alignment of the type.
1417    if (const FieldDecl *Field = dyn_cast<FieldDecl>(VD)) {
1418      const RecordDecl *Parent = Field->getParent();
1419      // We can only produce a sensible answer if the record is valid.
1420      if (!Parent->isInvalidDecl()) {
1421        const ASTRecordLayout &Layout = getASTRecordLayout(Parent);
1422
1423        // Start with the record's overall alignment.
1424        unsigned FieldAlign = toBits(Layout.getAlignment());
1425
1426        // Use the GCD of that and the offset within the record.
1427        uint64_t Offset = Layout.getFieldOffset(Field->getFieldIndex());
1428        if (Offset > 0) {
1429          // Alignment is always a power of 2, so the GCD will be a power of 2,
1430          // which means we get to do this crazy thing instead of Euclid's.
1431          uint64_t LowBitOfOffset = Offset & (~Offset + 1);
1432          if (LowBitOfOffset < FieldAlign)
1433            FieldAlign = static_cast<unsigned>(LowBitOfOffset);
1434        }
1435
1436        Align = std::min(Align, FieldAlign);
1437      }
1438    }
1439  }
1440
1441  return toCharUnitsFromBits(Align);
1442}
1443
1444// getTypeInfoDataSizeInChars - Return the size of a type, in
1445// chars. If the type is a record, its data size is returned.  This is
1446// the size of the memcpy that's performed when assigning this type
1447// using a trivial copy/move assignment operator.
1448std::pair<CharUnits, CharUnits>
1449ASTContext::getTypeInfoDataSizeInChars(QualType T) const {
1450  std::pair<CharUnits, CharUnits> sizeAndAlign = getTypeInfoInChars(T);
1451
1452  // In C++, objects can sometimes be allocated into the tail padding
1453  // of a base-class subobject.  We decide whether that's possible
1454  // during class layout, so here we can just trust the layout results.
1455  if (getLangOpts().CPlusPlus) {
1456    if (const RecordType *RT = T->getAs<RecordType>()) {
1457      const ASTRecordLayout &layout = getASTRecordLayout(RT->getDecl());
1458      sizeAndAlign.first = layout.getDataSize();
1459    }
1460  }
1461
1462  return sizeAndAlign;
1463}
1464
1465/// getConstantArrayInfoInChars - Performing the computation in CharUnits
1466/// instead of in bits prevents overflowing the uint64_t for some large arrays.
1467std::pair<CharUnits, CharUnits>
1468static getConstantArrayInfoInChars(const ASTContext &Context,
1469                                   const ConstantArrayType *CAT) {
1470  std::pair<CharUnits, CharUnits> EltInfo =
1471      Context.getTypeInfoInChars(CAT->getElementType());
1472  uint64_t Size = CAT->getSize().getZExtValue();
1473  assert((Size == 0 || static_cast<uint64_t>(EltInfo.first.getQuantity()) <=
1474              (uint64_t)(-1)/Size) &&
1475         "Overflow in array type char size evaluation");
1476  uint64_t Width = EltInfo.first.getQuantity() * Size;
1477  unsigned Align = EltInfo.second.getQuantity();
1478  if (!Context.getTargetInfo().getCXXABI().isMicrosoft() ||
1479      Context.getTargetInfo().getPointerWidth(0) == 64)
1480    Width = llvm::alignTo(Width, Align);
1481  return std::make_pair(CharUnits::fromQuantity(Width),
1482                        CharUnits::fromQuantity(Align));
1483}
1484
1485std::pair<CharUnits, CharUnits>
1486ASTContext::getTypeInfoInChars(const Type *T) const {
1487  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(T))
1488    return getConstantArrayInfoInChars(*this, CAT);
1489  TypeInfo Info = getTypeInfo(T);
1490  return std::make_pair(toCharUnitsFromBits(Info.Width),
1491                        toCharUnitsFromBits(Info.Align));
1492}
1493
1494std::pair<CharUnits, CharUnits>
1495ASTContext::getTypeInfoInChars(QualType T) const {
1496  return getTypeInfoInChars(T.getTypePtr());
1497}
1498
1499bool ASTContext::isAlignmentRequired(const Type *T) const {
1500  return getTypeInfo(T).AlignIsRequired;
1501}
1502
1503bool ASTContext::isAlignmentRequired(QualType T) const {
1504  return isAlignmentRequired(T.getTypePtr());
1505}
1506
1507TypeInfo ASTContext::getTypeInfo(const Type *T) const {
1508  TypeInfoMap::iterator I = MemoizedTypeInfo.find(T);
1509  if (I != MemoizedTypeInfo.end())
1510    return I->second;
1511
1512  // This call can invalidate MemoizedTypeInfo[T], so we need a second lookup.
1513  TypeInfo TI = getTypeInfoImpl(T);
1514  MemoizedTypeInfo[T] = TI;
1515  return TI;
1516}
1517
1518/// getTypeInfoImpl - Return the size of the specified type, in bits.  This
1519/// method does not work on incomplete types.
1520///
1521/// FIXME: Pointers into different addr spaces could have different sizes and
1522/// alignment requirements: getPointerInfo should take an AddrSpace, this
1523/// should take a QualType, &c.
1524TypeInfo ASTContext::getTypeInfoImpl(const Type *T) const {
1525  uint64_t Width = 0;
1526  unsigned Align = 8;
1527  bool AlignIsRequired = false;
1528  switch (T->getTypeClass()) {
1529#define TYPE(Class, Base)
1530#define ABSTRACT_TYPE(Class, Base)
1531#define NON_CANONICAL_TYPE(Class, Base)
1532#define DEPENDENT_TYPE(Class, Base) case Type::Class:
1533#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base)                       \
1534  case Type::Class:                                                            \
1535  assert(!T->isDependentType() && "should not see dependent types here");      \
1536  return getTypeInfo(cast<Class##Type>(T)->desugar().getTypePtr());
1537#include "clang/AST/TypeNodes.def"
1538    llvm_unreachable("Should not see dependent types");
1539
1540  case Type::FunctionNoProto:
1541  case Type::FunctionProto:
1542    // GCC extension: alignof(function) = 32 bits
1543    Width = 0;
1544    Align = 32;
1545    break;
1546
1547  case Type::IncompleteArray:
1548  case Type::VariableArray:
1549    Width = 0;
1550    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
1551    break;
1552
1553  case Type::ConstantArray: {
1554    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
1555
1556    TypeInfo EltInfo = getTypeInfo(CAT->getElementType());
1557    uint64_t Size = CAT->getSize().getZExtValue();
1558    assert((Size == 0 || EltInfo.Width <= (uint64_t)(-1) / Size) &&
1559           "Overflow in array type bit size evaluation");
1560    Width = EltInfo.Width * Size;
1561    Align = EltInfo.Align;
1562    if (!getTargetInfo().getCXXABI().isMicrosoft() ||
1563        getTargetInfo().getPointerWidth(0) == 64)
1564      Width = llvm::alignTo(Width, Align);
1565    break;
1566  }
1567  case Type::ExtVector:
1568  case Type::Vector: {
1569    const VectorType *VT = cast<VectorType>(T);
1570    TypeInfo EltInfo = getTypeInfo(VT->getElementType());
1571    Width = EltInfo.Width * VT->getNumElements();
1572    Align = Width;
1573    // If the alignment is not a power of 2, round up to the next power of 2.
1574    // This happens for non-power-of-2 length vectors.
1575    if (Align & (Align-1)) {
1576      Align = llvm::NextPowerOf2(Align);
1577      Width = llvm::alignTo(Width, Align);
1578    }
1579    // Adjust the alignment based on the target max.
1580    uint64_t TargetVectorAlign = Target->getMaxVectorAlign();
1581    if (TargetVectorAlign && TargetVectorAlign < Align)
1582      Align = TargetVectorAlign;
1583    break;
1584  }
1585
1586  case Type::Builtin:
1587    switch (cast<BuiltinType>(T)->getKind()) {
1588    default: llvm_unreachable("Unknown builtin type!");
1589    case BuiltinType::Void:
1590      // GCC extension: alignof(void) = 8 bits.
1591      Width = 0;
1592      Align = 8;
1593      break;
1594
1595    case BuiltinType::Bool:
1596      Width = Target->getBoolWidth();
1597      Align = Target->getBoolAlign();
1598      break;
1599    case BuiltinType::Char_S:
1600    case BuiltinType::Char_U:
1601    case BuiltinType::UChar:
1602    case BuiltinType::SChar:
1603      Width = Target->getCharWidth();
1604      Align = Target->getCharAlign();
1605      break;
1606    case BuiltinType::WChar_S:
1607    case BuiltinType::WChar_U:
1608      Width = Target->getWCharWidth();
1609      Align = Target->getWCharAlign();
1610      break;
1611    case BuiltinType::Char16:
1612      Width = Target->getChar16Width();
1613      Align = Target->getChar16Align();
1614      break;
1615    case BuiltinType::Char32:
1616      Width = Target->getChar32Width();
1617      Align = Target->getChar32Align();
1618      break;
1619    case BuiltinType::UShort:
1620    case BuiltinType::Short:
1621      Width = Target->getShortWidth();
1622      Align = Target->getShortAlign();
1623      break;
1624    case BuiltinType::UInt:
1625    case BuiltinType::Int:
1626      Width = Target->getIntWidth();
1627      Align = Target->getIntAlign();
1628      break;
1629    case BuiltinType::ULong:
1630    case BuiltinType::Long:
1631      Width = Target->getLongWidth();
1632      Align = Target->getLongAlign();
1633      break;
1634    case BuiltinType::ULongLong:
1635    case BuiltinType::LongLong:
1636      Width = Target->getLongLongWidth();
1637      Align = Target->getLongLongAlign();
1638      break;
1639    case BuiltinType::Int128:
1640    case BuiltinType::UInt128:
1641      Width = 128;
1642      Align = 128; // int128_t is 128-bit aligned on all targets.
1643      break;
1644    case BuiltinType::Half:
1645      Width = Target->getHalfWidth();
1646      Align = Target->getHalfAlign();
1647      break;
1648    case BuiltinType::Float:
1649      Width = Target->getFloatWidth();
1650      Align = Target->getFloatAlign();
1651      break;
1652    case BuiltinType::Double:
1653      Width = Target->getDoubleWidth();
1654      Align = Target->getDoubleAlign();
1655      break;
1656    case BuiltinType::LongDouble:
1657      Width = Target->getLongDoubleWidth();
1658      Align = Target->getLongDoubleAlign();
1659      break;
1660    case BuiltinType::Float128:
1661      Width = Target->getFloat128Width();
1662      Align = Target->getFloat128Align();
1663      break;
1664    case BuiltinType::NullPtr:
1665      Width = Target->getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
1666      Align = Target->getPointerAlign(0); //   == sizeof(void*)
1667      break;
1668    case BuiltinType::ObjCId:
1669    case BuiltinType::ObjCClass:
1670    case BuiltinType::ObjCSel:
1671      Width = Target->getPointerWidth(0);
1672      Align = Target->getPointerAlign(0);
1673      break;
1674    case BuiltinType::OCLSampler:
1675      // Samplers are modeled as integers.
1676      Width = Target->getIntWidth();
1677      Align = Target->getIntAlign();
1678      break;
1679    case BuiltinType::OCLEvent:
1680    case BuiltinType::OCLClkEvent:
1681    case BuiltinType::OCLQueue:
1682    case BuiltinType::OCLNDRange:
1683    case BuiltinType::OCLReserveID:
1684#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
1685    case BuiltinType::Id:
1686#include "clang/Basic/OpenCLImageTypes.def"
1687
1688      // Currently these types are pointers to opaque types.
1689      Width = Target->getPointerWidth(0);
1690      Align = Target->getPointerAlign(0);
1691      break;
1692    }
1693    break;
1694  case Type::ObjCObjectPointer:
1695    Width = Target->getPointerWidth(0);
1696    Align = Target->getPointerAlign(0);
1697    break;
1698  case Type::BlockPointer: {
1699    unsigned AS = getTargetAddressSpace(
1700        cast<BlockPointerType>(T)->getPointeeType());
1701    Width = Target->getPointerWidth(AS);
1702    Align = Target->getPointerAlign(AS);
1703    break;
1704  }
1705  case Type::LValueReference:
1706  case Type::RValueReference: {
1707    // alignof and sizeof should never enter this code path here, so we go
1708    // the pointer route.
1709    unsigned AS = getTargetAddressSpace(
1710        cast<ReferenceType>(T)->getPointeeType());
1711    Width = Target->getPointerWidth(AS);
1712    Align = Target->getPointerAlign(AS);
1713    break;
1714  }
1715  case Type::Pointer: {
1716    unsigned AS = getTargetAddressSpace(cast<PointerType>(T)->getPointeeType());
1717    Width = Target->getPointerWidth(AS);
1718    Align = Target->getPointerAlign(AS);
1719    break;
1720  }
1721  case Type::MemberPointer: {
1722    const MemberPointerType *MPT = cast<MemberPointerType>(T);
1723    std::tie(Width, Align) = ABI->getMemberPointerWidthAndAlign(MPT);
1724    break;
1725  }
1726  case Type::Complex: {
1727    // Complex types have the same alignment as their elements, but twice the
1728    // size.
1729    TypeInfo EltInfo = getTypeInfo(cast<ComplexType>(T)->getElementType());
1730    Width = EltInfo.Width * 2;
1731    Align = EltInfo.Align;
1732    break;
1733  }
1734  case Type::ObjCObject:
1735    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
1736  case Type::Adjusted:
1737  case Type::Decayed:
1738    return getTypeInfo(cast<AdjustedType>(T)->getAdjustedType().getTypePtr());
1739  case Type::ObjCInterface: {
1740    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
1741    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
1742    Width = toBits(Layout.getSize());
1743    Align = toBits(Layout.getAlignment());
1744    break;
1745  }
1746  case Type::Record:
1747  case Type::Enum: {
1748    const TagType *TT = cast<TagType>(T);
1749
1750    if (TT->getDecl()->isInvalidDecl()) {
1751      Width = 8;
1752      Align = 8;
1753      break;
1754    }
1755
1756    if (const EnumType *ET = dyn_cast<EnumType>(TT)) {
1757      const EnumDecl *ED = ET->getDecl();
1758      TypeInfo Info =
1759          getTypeInfo(ED->getIntegerType()->getUnqualifiedDesugaredType());
1760      if (unsigned AttrAlign = ED->getMaxAlignment()) {
1761        Info.Align = AttrAlign;
1762        Info.AlignIsRequired = true;
1763      }
1764      return Info;
1765    }
1766
1767    const RecordType *RT = cast<RecordType>(TT);
1768    const RecordDecl *RD = RT->getDecl();
1769    const ASTRecordLayout &Layout = getASTRecordLayout(RD);
1770    Width = toBits(Layout.getSize());
1771    Align = toBits(Layout.getAlignment());
1772    AlignIsRequired = RD->hasAttr<AlignedAttr>();
1773    break;
1774  }
1775
1776  case Type::SubstTemplateTypeParm:
1777    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
1778                       getReplacementType().getTypePtr());
1779
1780  case Type::Auto: {
1781    const AutoType *A = cast<AutoType>(T);
1782    assert(!A->getDeducedType().isNull() &&
1783           "cannot request the size of an undeduced or dependent auto type");
1784    return getTypeInfo(A->getDeducedType().getTypePtr());
1785  }
1786
1787  case Type::Paren:
1788    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
1789
1790  case Type::Typedef: {
1791    const TypedefNameDecl *Typedef = cast<TypedefType>(T)->getDecl();
1792    TypeInfo Info = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
1793    // If the typedef has an aligned attribute on it, it overrides any computed
1794    // alignment we have.  This violates the GCC documentation (which says that
1795    // attribute(aligned) can only round up) but matches its implementation.
1796    if (unsigned AttrAlign = Typedef->getMaxAlignment()) {
1797      Align = AttrAlign;
1798      AlignIsRequired = true;
1799    } else {
1800      Align = Info.Align;
1801      AlignIsRequired = Info.AlignIsRequired;
1802    }
1803    Width = Info.Width;
1804    break;
1805  }
1806
1807  case Type::Elaborated:
1808    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
1809
1810  case Type::Attributed:
1811    return getTypeInfo(
1812                  cast<AttributedType>(T)->getEquivalentType().getTypePtr());
1813
1814  case Type::Atomic: {
1815    // Start with the base type information.
1816    TypeInfo Info = getTypeInfo(cast<AtomicType>(T)->getValueType());
1817    Width = Info.Width;
1818    Align = Info.Align;
1819
1820    // If the size of the type doesn't exceed the platform's max
1821    // atomic promotion width, make the size and alignment more
1822    // favorable to atomic operations:
1823    if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth()) {
1824      // Round the size up to a power of 2.
1825      if (!llvm::isPowerOf2_64(Width))
1826        Width = llvm::NextPowerOf2(Width);
1827
1828      // Set the alignment equal to the size.
1829      Align = static_cast<unsigned>(Width);
1830    }
1831  }
1832  break;
1833
1834  case Type::Pipe: {
1835    TypeInfo Info = getTypeInfo(cast<PipeType>(T)->getElementType());
1836    Width = Info.Width;
1837    Align = Info.Align;
1838  }
1839
1840  }
1841
1842  assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
1843  return TypeInfo(Width, Align, AlignIsRequired);
1844}
1845
1846unsigned ASTContext::getOpenMPDefaultSimdAlign(QualType T) const {
1847  unsigned SimdAlign = getTargetInfo().getSimdDefaultAlign();
1848  // Target ppc64 with QPX: simd default alignment for pointer to double is 32.
1849  if ((getTargetInfo().getTriple().getArch() == llvm::Triple::ppc64 ||
1850       getTargetInfo().getTriple().getArch() == llvm::Triple::ppc64le) &&
1851      getTargetInfo().getABI() == "elfv1-qpx" &&
1852      T->isSpecificBuiltinType(BuiltinType::Double))
1853    SimdAlign = 256;
1854  return SimdAlign;
1855}
1856
1857/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1858CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1859  return CharUnits::fromQuantity(BitSize / getCharWidth());
1860}
1861
1862/// toBits - Convert a size in characters to a size in characters.
1863int64_t ASTContext::toBits(CharUnits CharSize) const {
1864  return CharSize.getQuantity() * getCharWidth();
1865}
1866
1867/// getTypeSizeInChars - Return the size of the specified type, in characters.
1868/// This method does not work on incomplete types.
1869CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1870  return getTypeInfoInChars(T).first;
1871}
1872CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1873  return getTypeInfoInChars(T).first;
1874}
1875
1876/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1877/// characters. This method does not work on incomplete types.
1878CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1879  return toCharUnitsFromBits(getTypeAlign(T));
1880}
1881CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1882  return toCharUnitsFromBits(getTypeAlign(T));
1883}
1884
1885/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1886/// type for the current target in bits.  This can be different than the ABI
1887/// alignment in cases where it is beneficial for performance to overalign
1888/// a data type.
1889unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1890  TypeInfo TI = getTypeInfo(T);
1891  unsigned ABIAlign = TI.Align;
1892
1893  T = T->getBaseElementTypeUnsafe();
1894
1895  // The preferred alignment of member pointers is that of a pointer.
1896  if (T->isMemberPointerType())
1897    return getPreferredTypeAlign(getPointerDiffType().getTypePtr());
1898
1899  if (!Target->allowsLargerPreferedTypeAlignment())
1900    return ABIAlign;
1901
1902  // Double and long long should be naturally aligned if possible.
1903  if (const ComplexType *CT = T->getAs<ComplexType>())
1904    T = CT->getElementType().getTypePtr();
1905  if (const EnumType *ET = T->getAs<EnumType>())
1906    T = ET->getDecl()->getIntegerType().getTypePtr();
1907  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1908      T->isSpecificBuiltinType(BuiltinType::LongLong) ||
1909      T->isSpecificBuiltinType(BuiltinType::ULongLong))
1910    // Don't increase the alignment if an alignment attribute was specified on a
1911    // typedef declaration.
1912    if (!TI.AlignIsRequired)
1913      return std::max(ABIAlign, (unsigned)getTypeSize(T));
1914
1915  return ABIAlign;
1916}
1917
1918/// getTargetDefaultAlignForAttributeAligned - Return the default alignment
1919/// for __attribute__((aligned)) on this target, to be used if no alignment
1920/// value is specified.
1921unsigned ASTContext::getTargetDefaultAlignForAttributeAligned() const {
1922  return getTargetInfo().getDefaultAlignForAttributeAligned();
1923}
1924
1925/// getAlignOfGlobalVar - Return the alignment in bits that should be given
1926/// to a global variable of the specified type.
1927unsigned ASTContext::getAlignOfGlobalVar(QualType T) const {
1928  return std::max(getTypeAlign(T), getTargetInfo().getMinGlobalAlign());
1929}
1930
1931/// getAlignOfGlobalVarInChars - Return the alignment in characters that
1932/// should be given to a global variable of the specified type.
1933CharUnits ASTContext::getAlignOfGlobalVarInChars(QualType T) const {
1934  return toCharUnitsFromBits(getAlignOfGlobalVar(T));
1935}
1936
1937CharUnits ASTContext::getOffsetOfBaseWithVBPtr(const CXXRecordDecl *RD) const {
1938  CharUnits Offset = CharUnits::Zero();
1939  const ASTRecordLayout *Layout = &getASTRecordLayout(RD);
1940  while (const CXXRecordDecl *Base = Layout->getBaseSharingVBPtr()) {
1941    Offset += Layout->getBaseClassOffset(Base);
1942    Layout = &getASTRecordLayout(Base);
1943  }
1944  return Offset;
1945}
1946
1947/// DeepCollectObjCIvars -
1948/// This routine first collects all declared, but not synthesized, ivars in
1949/// super class and then collects all ivars, including those synthesized for
1950/// current class. This routine is used for implementation of current class
1951/// when all ivars, declared and synthesized are known.
1952///
1953void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1954                                      bool leafClass,
1955                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1956  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1957    DeepCollectObjCIvars(SuperClass, false, Ivars);
1958  if (!leafClass) {
1959    for (const auto *I : OI->ivars())
1960      Ivars.push_back(I);
1961  } else {
1962    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1963    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1964         Iv= Iv->getNextIvar())
1965      Ivars.push_back(Iv);
1966  }
1967}
1968
1969/// CollectInheritedProtocols - Collect all protocols in current class and
1970/// those inherited by it.
1971void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1972                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1973  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1974    // We can use protocol_iterator here instead of
1975    // all_referenced_protocol_iterator since we are walking all categories.
1976    for (auto *Proto : OI->all_referenced_protocols()) {
1977      CollectInheritedProtocols(Proto, Protocols);
1978    }
1979
1980    // Categories of this Interface.
1981    for (const auto *Cat : OI->visible_categories())
1982      CollectInheritedProtocols(Cat, Protocols);
1983
1984    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1985      while (SD) {
1986        CollectInheritedProtocols(SD, Protocols);
1987        SD = SD->getSuperClass();
1988      }
1989  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1990    for (auto *Proto : OC->protocols()) {
1991      CollectInheritedProtocols(Proto, Protocols);
1992    }
1993  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
1994    // Insert the protocol.
1995    if (!Protocols.insert(
1996          const_cast<ObjCProtocolDecl *>(OP->getCanonicalDecl())).second)
1997      return;
1998
1999    for (auto *Proto : OP->protocols())
2000      CollectInheritedProtocols(Proto, Protocols);
2001  }
2002}
2003
2004unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
2005  unsigned count = 0;
2006  // Count ivars declared in class extension.
2007  for (const auto *Ext : OI->known_extensions())
2008    count += Ext->ivar_size();
2009
2010  // Count ivar defined in this class's implementation.  This
2011  // includes synthesized ivars.
2012  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
2013    count += ImplDecl->ivar_size();
2014
2015  return count;
2016}
2017
2018bool ASTContext::isSentinelNullExpr(const Expr *E) {
2019  if (!E)
2020    return false;
2021
2022  // nullptr_t is always treated as null.
2023  if (E->getType()->isNullPtrType()) return true;
2024
2025  if (E->getType()->isAnyPointerType() &&
2026      E->IgnoreParenCasts()->isNullPointerConstant(*this,
2027                                                Expr::NPC_ValueDependentIsNull))
2028    return true;
2029
2030  // Unfortunately, __null has type 'int'.
2031  if (isa<GNUNullExpr>(E)) return true;
2032
2033  return false;
2034}
2035
2036/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
2037ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
2038  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
2039    I = ObjCImpls.find(D);
2040  if (I != ObjCImpls.end())
2041    return cast<ObjCImplementationDecl>(I->second);
2042  return nullptr;
2043}
2044/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
2045ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
2046  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
2047    I = ObjCImpls.find(D);
2048  if (I != ObjCImpls.end())
2049    return cast<ObjCCategoryImplDecl>(I->second);
2050  return nullptr;
2051}
2052
2053/// \brief Set the implementation of ObjCInterfaceDecl.
2054void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
2055                           ObjCImplementationDecl *ImplD) {
2056  assert(IFaceD && ImplD && "Passed null params");
2057  ObjCImpls[IFaceD] = ImplD;
2058}
2059/// \brief Set the implementation of ObjCCategoryDecl.
2060void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
2061                           ObjCCategoryImplDecl *ImplD) {
2062  assert(CatD && ImplD && "Passed null params");
2063  ObjCImpls[CatD] = ImplD;
2064}
2065
2066const ObjCMethodDecl *
2067ASTContext::getObjCMethodRedeclaration(const ObjCMethodDecl *MD) const {
2068  return ObjCMethodRedecls.lookup(MD);
2069}
2070
2071void ASTContext::setObjCMethodRedeclaration(const ObjCMethodDecl *MD,
2072                                            const ObjCMethodDecl *Redecl) {
2073  assert(!getObjCMethodRedeclaration(MD) && "MD already has a redeclaration");
2074  ObjCMethodRedecls[MD] = Redecl;
2075}
2076
2077const ObjCInterfaceDecl *ASTContext::getObjContainingInterface(
2078                                              const NamedDecl *ND) const {
2079  if (const ObjCInterfaceDecl *ID =
2080          dyn_cast<ObjCInterfaceDecl>(ND->getDeclContext()))
2081    return ID;
2082  if (const ObjCCategoryDecl *CD =
2083          dyn_cast<ObjCCategoryDecl>(ND->getDeclContext()))
2084    return CD->getClassInterface();
2085  if (const ObjCImplDecl *IMD =
2086          dyn_cast<ObjCImplDecl>(ND->getDeclContext()))
2087    return IMD->getClassInterface();
2088
2089  return nullptr;
2090}
2091
2092/// \brief Get the copy initialization expression of VarDecl,or NULL if
2093/// none exists.
2094Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
2095  assert(VD && "Passed null params");
2096  assert(VD->hasAttr<BlocksAttr>() &&
2097         "getBlockVarCopyInits - not __block var");
2098  llvm::DenseMap<const VarDecl*, Expr*>::iterator
2099    I = BlockVarCopyInits.find(VD);
2100  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : nullptr;
2101}
2102
2103/// \brief Set the copy inialization expression of a block var decl.
2104void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
2105  assert(VD && Init && "Passed null params");
2106  assert(VD->hasAttr<BlocksAttr>() &&
2107         "setBlockVarCopyInits - not __block var");
2108  BlockVarCopyInits[VD] = Init;
2109}
2110
2111TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
2112                                                 unsigned DataSize) const {
2113  if (!DataSize)
2114    DataSize = TypeLoc::getFullDataSizeForType(T);
2115  else
2116    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
2117           "incorrect data size provided to CreateTypeSourceInfo!");
2118
2119  TypeSourceInfo *TInfo =
2120    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
2121  new (TInfo) TypeSourceInfo(T);
2122  return TInfo;
2123}
2124
2125TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
2126                                                     SourceLocation L) const {
2127  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
2128  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
2129  return DI;
2130}
2131
2132const ASTRecordLayout &
2133ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
2134  return getObjCLayout(D, nullptr);
2135}
2136
2137const ASTRecordLayout &
2138ASTContext::getASTObjCImplementationLayout(
2139                                        const ObjCImplementationDecl *D) const {
2140  return getObjCLayout(D->getClassInterface(), D);
2141}
2142
2143//===----------------------------------------------------------------------===//
2144//                   Type creation/memoization methods
2145//===----------------------------------------------------------------------===//
2146
2147QualType
2148ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
2149  unsigned fastQuals = quals.getFastQualifiers();
2150  quals.removeFastQualifiers();
2151
2152  // Check if we've already instantiated this type.
2153  llvm::FoldingSetNodeID ID;
2154  ExtQuals::Profile(ID, baseType, quals);
2155  void *insertPos = nullptr;
2156  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
2157    assert(eq->getQualifiers() == quals);
2158    return QualType(eq, fastQuals);
2159  }
2160
2161  // If the base type is not canonical, make the appropriate canonical type.
2162  QualType canon;
2163  if (!baseType->isCanonicalUnqualified()) {
2164    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
2165    canonSplit.Quals.addConsistentQualifiers(quals);
2166    canon = getExtQualType(canonSplit.Ty, canonSplit.Quals);
2167
2168    // Re-find the insert position.
2169    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
2170  }
2171
2172  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
2173  ExtQualNodes.InsertNode(eq, insertPos);
2174  return QualType(eq, fastQuals);
2175}
2176
2177QualType
2178ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
2179  QualType CanT = getCanonicalType(T);
2180  if (CanT.getAddressSpace() == AddressSpace)
2181    return T;
2182
2183  // If we are composing extended qualifiers together, merge together
2184  // into one ExtQuals node.
2185  QualifierCollector Quals;
2186  const Type *TypeNode = Quals.strip(T);
2187
2188  // If this type already has an address space specified, it cannot get
2189  // another one.
2190  assert(!Quals.hasAddressSpace() &&
2191         "Type cannot be in multiple addr spaces!");
2192  Quals.addAddressSpace(AddressSpace);
2193
2194  return getExtQualType(TypeNode, Quals);
2195}
2196
2197QualType ASTContext::getObjCGCQualType(QualType T,
2198                                       Qualifiers::GC GCAttr) const {
2199  QualType CanT = getCanonicalType(T);
2200  if (CanT.getObjCGCAttr() == GCAttr)
2201    return T;
2202
2203  if (const PointerType *ptr = T->getAs<PointerType>()) {
2204    QualType Pointee = ptr->getPointeeType();
2205    if (Pointee->isAnyPointerType()) {
2206      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
2207      return getPointerType(ResultType);
2208    }
2209  }
2210
2211  // If we are composing extended qualifiers together, merge together
2212  // into one ExtQuals node.
2213  QualifierCollector Quals;
2214  const Type *TypeNode = Quals.strip(T);
2215
2216  // If this type already has an ObjCGC specified, it cannot get
2217  // another one.
2218  assert(!Quals.hasObjCGCAttr() &&
2219         "Type cannot have multiple ObjCGCs!");
2220  Quals.addObjCGCAttr(GCAttr);
2221
2222  return getExtQualType(TypeNode, Quals);
2223}
2224
2225const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
2226                                                   FunctionType::ExtInfo Info) {
2227  if (T->getExtInfo() == Info)
2228    return T;
2229
2230  QualType Result;
2231  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
2232    Result = getFunctionNoProtoType(FNPT->getReturnType(), Info);
2233  } else {
2234    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
2235    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
2236    EPI.ExtInfo = Info;
2237    Result = getFunctionType(FPT->getReturnType(), FPT->getParamTypes(), EPI);
2238  }
2239
2240  return cast<FunctionType>(Result.getTypePtr());
2241}
2242
2243void ASTContext::adjustDeducedFunctionResultType(FunctionDecl *FD,
2244                                                 QualType ResultType) {
2245  FD = FD->getMostRecentDecl();
2246  while (true) {
2247    const FunctionProtoType *FPT = FD->getType()->castAs<FunctionProtoType>();
2248    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
2249    FD->setType(getFunctionType(ResultType, FPT->getParamTypes(), EPI));
2250    if (FunctionDecl *Next = FD->getPreviousDecl())
2251      FD = Next;
2252    else
2253      break;
2254  }
2255  if (ASTMutationListener *L = getASTMutationListener())
2256    L->DeducedReturnType(FD, ResultType);
2257}
2258
2259/// Get a function type and produce the equivalent function type with the
2260/// specified exception specification. Type sugar that can be present on a
2261/// declaration of a function with an exception specification is permitted
2262/// and preserved. Other type sugar (for instance, typedefs) is not.
2263static QualType getFunctionTypeWithExceptionSpec(
2264    ASTContext &Context, QualType Orig,
2265    const FunctionProtoType::ExceptionSpecInfo &ESI) {
2266  // Might have some parens.
2267  if (auto *PT = dyn_cast<ParenType>(Orig))
2268    return Context.getParenType(
2269        getFunctionTypeWithExceptionSpec(Context, PT->getInnerType(), ESI));
2270
2271  // Might have a calling-convention attribute.
2272  if (auto *AT = dyn_cast<AttributedType>(Orig))
2273    return Context.getAttributedType(
2274        AT->getAttrKind(),
2275        getFunctionTypeWithExceptionSpec(Context, AT->getModifiedType(), ESI),
2276        getFunctionTypeWithExceptionSpec(Context, AT->getEquivalentType(),
2277                                         ESI));
2278
2279  // Anything else must be a function type. Rebuild it with the new exception
2280  // specification.
2281  const FunctionProtoType *Proto = cast<FunctionProtoType>(Orig);
2282  return Context.getFunctionType(
2283      Proto->getReturnType(), Proto->getParamTypes(),
2284      Proto->getExtProtoInfo().withExceptionSpec(ESI));
2285}
2286
2287void ASTContext::adjustExceptionSpec(
2288    FunctionDecl *FD, const FunctionProtoType::ExceptionSpecInfo &ESI,
2289    bool AsWritten) {
2290  // Update the type.
2291  QualType Updated =
2292      getFunctionTypeWithExceptionSpec(*this, FD->getType(), ESI);
2293  FD->setType(Updated);
2294
2295  if (!AsWritten)
2296    return;
2297
2298  // Update the type in the type source information too.
2299  if (TypeSourceInfo *TSInfo = FD->getTypeSourceInfo()) {
2300    // If the type and the type-as-written differ, we may need to update
2301    // the type-as-written too.
2302    if (TSInfo->getType() != FD->getType())
2303      Updated = getFunctionTypeWithExceptionSpec(*this, TSInfo->getType(), ESI);
2304
2305    // FIXME: When we get proper type location information for exceptions,
2306    // we'll also have to rebuild the TypeSourceInfo. For now, we just patch
2307    // up the TypeSourceInfo;
2308    assert(TypeLoc::getFullDataSizeForType(Updated) ==
2309               TypeLoc::getFullDataSizeForType(TSInfo->getType()) &&
2310           "TypeLoc size mismatch from updating exception specification");
2311    TSInfo->overrideType(Updated);
2312  }
2313}
2314
2315/// getComplexType - Return the uniqued reference to the type for a complex
2316/// number with the specified element type.
2317QualType ASTContext::getComplexType(QualType T) const {
2318  // Unique pointers, to guarantee there is only one pointer of a particular
2319  // structure.
2320  llvm::FoldingSetNodeID ID;
2321  ComplexType::Profile(ID, T);
2322
2323  void *InsertPos = nullptr;
2324  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
2325    return QualType(CT, 0);
2326
2327  // If the pointee type isn't canonical, this won't be a canonical type either,
2328  // so fill in the canonical type field.
2329  QualType Canonical;
2330  if (!T.isCanonical()) {
2331    Canonical = getComplexType(getCanonicalType(T));
2332
2333    // Get the new insert position for the node we care about.
2334    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
2335    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2336  }
2337  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
2338  Types.push_back(New);
2339  ComplexTypes.InsertNode(New, InsertPos);
2340  return QualType(New, 0);
2341}
2342
2343/// getPointerType - Return the uniqued reference to the type for a pointer to
2344/// the specified type.
2345QualType ASTContext::getPointerType(QualType T) const {
2346  // Unique pointers, to guarantee there is only one pointer of a particular
2347  // structure.
2348  llvm::FoldingSetNodeID ID;
2349  PointerType::Profile(ID, T);
2350
2351  void *InsertPos = nullptr;
2352  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2353    return QualType(PT, 0);
2354
2355  // If the pointee type isn't canonical, this won't be a canonical type either,
2356  // so fill in the canonical type field.
2357  QualType Canonical;
2358  if (!T.isCanonical()) {
2359    Canonical = getPointerType(getCanonicalType(T));
2360
2361    // Get the new insert position for the node we care about.
2362    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2363    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2364  }
2365  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
2366  Types.push_back(New);
2367  PointerTypes.InsertNode(New, InsertPos);
2368  return QualType(New, 0);
2369}
2370
2371QualType ASTContext::getAdjustedType(QualType Orig, QualType New) const {
2372  llvm::FoldingSetNodeID ID;
2373  AdjustedType::Profile(ID, Orig, New);
2374  void *InsertPos = nullptr;
2375  AdjustedType *AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
2376  if (AT)
2377    return QualType(AT, 0);
2378
2379  QualType Canonical = getCanonicalType(New);
2380
2381  // Get the new insert position for the node we care about.
2382  AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
2383  assert(!AT && "Shouldn't be in the map!");
2384
2385  AT = new (*this, TypeAlignment)
2386      AdjustedType(Type::Adjusted, Orig, New, Canonical);
2387  Types.push_back(AT);
2388  AdjustedTypes.InsertNode(AT, InsertPos);
2389  return QualType(AT, 0);
2390}
2391
2392QualType ASTContext::getDecayedType(QualType T) const {
2393  assert((T->isArrayType() || T->isFunctionType()) && "T does not decay");
2394
2395  QualType Decayed;
2396
2397  // C99 6.7.5.3p7:
2398  //   A declaration of a parameter as "array of type" shall be
2399  //   adjusted to "qualified pointer to type", where the type
2400  //   qualifiers (if any) are those specified within the [ and ] of
2401  //   the array type derivation.
2402  if (T->isArrayType())
2403    Decayed = getArrayDecayedType(T);
2404
2405  // C99 6.7.5.3p8:
2406  //   A declaration of a parameter as "function returning type"
2407  //   shall be adjusted to "pointer to function returning type", as
2408  //   in 6.3.2.1.
2409  if (T->isFunctionType())
2410    Decayed = getPointerType(T);
2411
2412  llvm::FoldingSetNodeID ID;
2413  AdjustedType::Profile(ID, T, Decayed);
2414  void *InsertPos = nullptr;
2415  AdjustedType *AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
2416  if (AT)
2417    return QualType(AT, 0);
2418
2419  QualType Canonical = getCanonicalType(Decayed);
2420
2421  // Get the new insert position for the node we care about.
2422  AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
2423  assert(!AT && "Shouldn't be in the map!");
2424
2425  AT = new (*this, TypeAlignment) DecayedType(T, Decayed, Canonical);
2426  Types.push_back(AT);
2427  AdjustedTypes.InsertNode(AT, InsertPos);
2428  return QualType(AT, 0);
2429}
2430
2431/// getBlockPointerType - Return the uniqued reference to the type for
2432/// a pointer to the specified block.
2433QualType ASTContext::getBlockPointerType(QualType T) const {
2434  assert(T->isFunctionType() && "block of function types only");
2435  // Unique pointers, to guarantee there is only one block of a particular
2436  // structure.
2437  llvm::FoldingSetNodeID ID;
2438  BlockPointerType::Profile(ID, T);
2439
2440  void *InsertPos = nullptr;
2441  if (BlockPointerType *PT =
2442        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2443    return QualType(PT, 0);
2444
2445  // If the block pointee type isn't canonical, this won't be a canonical
2446  // type either so fill in the canonical type field.
2447  QualType Canonical;
2448  if (!T.isCanonical()) {
2449    Canonical = getBlockPointerType(getCanonicalType(T));
2450
2451    // Get the new insert position for the node we care about.
2452    BlockPointerType *NewIP =
2453      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2454    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2455  }
2456  BlockPointerType *New
2457    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
2458  Types.push_back(New);
2459  BlockPointerTypes.InsertNode(New, InsertPos);
2460  return QualType(New, 0);
2461}
2462
2463/// getLValueReferenceType - Return the uniqued reference to the type for an
2464/// lvalue reference to the specified type.
2465QualType
2466ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
2467  assert(getCanonicalType(T) != OverloadTy &&
2468         "Unresolved overloaded function type");
2469
2470  // Unique pointers, to guarantee there is only one pointer of a particular
2471  // structure.
2472  llvm::FoldingSetNodeID ID;
2473  ReferenceType::Profile(ID, T, SpelledAsLValue);
2474
2475  void *InsertPos = nullptr;
2476  if (LValueReferenceType *RT =
2477        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
2478    return QualType(RT, 0);
2479
2480  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
2481
2482  // If the referencee type isn't canonical, this won't be a canonical type
2483  // either, so fill in the canonical type field.
2484  QualType Canonical;
2485  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
2486    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
2487    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
2488
2489    // Get the new insert position for the node we care about.
2490    LValueReferenceType *NewIP =
2491      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
2492    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2493  }
2494
2495  LValueReferenceType *New
2496    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
2497                                                     SpelledAsLValue);
2498  Types.push_back(New);
2499  LValueReferenceTypes.InsertNode(New, InsertPos);
2500
2501  return QualType(New, 0);
2502}
2503
2504/// getRValueReferenceType - Return the uniqued reference to the type for an
2505/// rvalue reference to the specified type.
2506QualType ASTContext::getRValueReferenceType(QualType T) const {
2507  // Unique pointers, to guarantee there is only one pointer of a particular
2508  // structure.
2509  llvm::FoldingSetNodeID ID;
2510  ReferenceType::Profile(ID, T, false);
2511
2512  void *InsertPos = nullptr;
2513  if (RValueReferenceType *RT =
2514        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
2515    return QualType(RT, 0);
2516
2517  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
2518
2519  // If the referencee type isn't canonical, this won't be a canonical type
2520  // either, so fill in the canonical type field.
2521  QualType Canonical;
2522  if (InnerRef || !T.isCanonical()) {
2523    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
2524    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
2525
2526    // Get the new insert position for the node we care about.
2527    RValueReferenceType *NewIP =
2528      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
2529    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2530  }
2531
2532  RValueReferenceType *New
2533    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
2534  Types.push_back(New);
2535  RValueReferenceTypes.InsertNode(New, InsertPos);
2536  return QualType(New, 0);
2537}
2538
2539/// getMemberPointerType - Return the uniqued reference to the type for a
2540/// member pointer to the specified type, in the specified class.
2541QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
2542  // Unique pointers, to guarantee there is only one pointer of a particular
2543  // structure.
2544  llvm::FoldingSetNodeID ID;
2545  MemberPointerType::Profile(ID, T, Cls);
2546
2547  void *InsertPos = nullptr;
2548  if (MemberPointerType *PT =
2549      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2550    return QualType(PT, 0);
2551
2552  // If the pointee or class type isn't canonical, this won't be a canonical
2553  // type either, so fill in the canonical type field.
2554  QualType Canonical;
2555  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
2556    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
2557
2558    // Get the new insert position for the node we care about.
2559    MemberPointerType *NewIP =
2560      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2561    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2562  }
2563  MemberPointerType *New
2564    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
2565  Types.push_back(New);
2566  MemberPointerTypes.InsertNode(New, InsertPos);
2567  return QualType(New, 0);
2568}
2569
2570/// getConstantArrayType - Return the unique reference to the type for an
2571/// array of the specified element type.
2572QualType ASTContext::getConstantArrayType(QualType EltTy,
2573                                          const llvm::APInt &ArySizeIn,
2574                                          ArrayType::ArraySizeModifier ASM,
2575                                          unsigned IndexTypeQuals) const {
2576  assert((EltTy->isDependentType() ||
2577          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
2578         "Constant array of VLAs is illegal!");
2579
2580  // Convert the array size into a canonical width matching the pointer size for
2581  // the target.
2582  llvm::APInt ArySize(ArySizeIn);
2583  ArySize =
2584    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
2585
2586  llvm::FoldingSetNodeID ID;
2587  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
2588
2589  void *InsertPos = nullptr;
2590  if (ConstantArrayType *ATP =
2591      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
2592    return QualType(ATP, 0);
2593
2594  // If the element type isn't canonical or has qualifiers, this won't
2595  // be a canonical type either, so fill in the canonical type field.
2596  QualType Canon;
2597  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2598    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2599    Canon = getConstantArrayType(QualType(canonSplit.Ty, 0), ArySize,
2600                                 ASM, IndexTypeQuals);
2601    Canon = getQualifiedType(Canon, canonSplit.Quals);
2602
2603    // Get the new insert position for the node we care about.
2604    ConstantArrayType *NewIP =
2605      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
2606    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2607  }
2608
2609  ConstantArrayType *New = new(*this,TypeAlignment)
2610    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
2611  ConstantArrayTypes.InsertNode(New, InsertPos);
2612  Types.push_back(New);
2613  return QualType(New, 0);
2614}
2615
2616/// getVariableArrayDecayedType - Turns the given type, which may be
2617/// variably-modified, into the corresponding type with all the known
2618/// sizes replaced with [*].
2619QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
2620  // Vastly most common case.
2621  if (!type->isVariablyModifiedType()) return type;
2622
2623  QualType result;
2624
2625  SplitQualType split = type.getSplitDesugaredType();
2626  const Type *ty = split.Ty;
2627  switch (ty->getTypeClass()) {
2628#define TYPE(Class, Base)
2629#define ABSTRACT_TYPE(Class, Base)
2630#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
2631#include "clang/AST/TypeNodes.def"
2632    llvm_unreachable("didn't desugar past all non-canonical types?");
2633
2634  // These types should never be variably-modified.
2635  case Type::Builtin:
2636  case Type::Complex:
2637  case Type::Vector:
2638  case Type::ExtVector:
2639  case Type::DependentSizedExtVector:
2640  case Type::ObjCObject:
2641  case Type::ObjCInterface:
2642  case Type::ObjCObjectPointer:
2643  case Type::Record:
2644  case Type::Enum:
2645  case Type::UnresolvedUsing:
2646  case Type::TypeOfExpr:
2647  case Type::TypeOf:
2648  case Type::Decltype:
2649  case Type::UnaryTransform:
2650  case Type::DependentName:
2651  case Type::InjectedClassName:
2652  case Type::TemplateSpecialization:
2653  case Type::DependentTemplateSpecialization:
2654  case Type::TemplateTypeParm:
2655  case Type::SubstTemplateTypeParmPack:
2656  case Type::Auto:
2657  case Type::PackExpansion:
2658    llvm_unreachable("type should never be variably-modified");
2659
2660  // These types can be variably-modified but should never need to
2661  // further decay.
2662  case Type::FunctionNoProto:
2663  case Type::FunctionProto:
2664  case Type::BlockPointer:
2665  case Type::MemberPointer:
2666  case Type::Pipe:
2667    return type;
2668
2669  // These types can be variably-modified.  All these modifications
2670  // preserve structure except as noted by comments.
2671  // TODO: if we ever care about optimizing VLAs, there are no-op
2672  // optimizations available here.
2673  case Type::Pointer:
2674    result = getPointerType(getVariableArrayDecayedType(
2675                              cast<PointerType>(ty)->getPointeeType()));
2676    break;
2677
2678  case Type::LValueReference: {
2679    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
2680    result = getLValueReferenceType(
2681                 getVariableArrayDecayedType(lv->getPointeeType()),
2682                                    lv->isSpelledAsLValue());
2683    break;
2684  }
2685
2686  case Type::RValueReference: {
2687    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
2688    result = getRValueReferenceType(
2689                 getVariableArrayDecayedType(lv->getPointeeType()));
2690    break;
2691  }
2692
2693  case Type::Atomic: {
2694    const AtomicType *at = cast<AtomicType>(ty);
2695    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
2696    break;
2697  }
2698
2699  case Type::ConstantArray: {
2700    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
2701    result = getConstantArrayType(
2702                 getVariableArrayDecayedType(cat->getElementType()),
2703                                  cat->getSize(),
2704                                  cat->getSizeModifier(),
2705                                  cat->getIndexTypeCVRQualifiers());
2706    break;
2707  }
2708
2709  case Type::DependentSizedArray: {
2710    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
2711    result = getDependentSizedArrayType(
2712                 getVariableArrayDecayedType(dat->getElementType()),
2713                                        dat->getSizeExpr(),
2714                                        dat->getSizeModifier(),
2715                                        dat->getIndexTypeCVRQualifiers(),
2716                                        dat->getBracketsRange());
2717    break;
2718  }
2719
2720  // Turn incomplete types into [*] types.
2721  case Type::IncompleteArray: {
2722    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
2723    result = getVariableArrayType(
2724                 getVariableArrayDecayedType(iat->getElementType()),
2725                                  /*size*/ nullptr,
2726                                  ArrayType::Normal,
2727                                  iat->getIndexTypeCVRQualifiers(),
2728                                  SourceRange());
2729    break;
2730  }
2731
2732  // Turn VLA types into [*] types.
2733  case Type::VariableArray: {
2734    const VariableArrayType *vat = cast<VariableArrayType>(ty);
2735    result = getVariableArrayType(
2736                 getVariableArrayDecayedType(vat->getElementType()),
2737                                  /*size*/ nullptr,
2738                                  ArrayType::Star,
2739                                  vat->getIndexTypeCVRQualifiers(),
2740                                  vat->getBracketsRange());
2741    break;
2742  }
2743  }
2744
2745  // Apply the top-level qualifiers from the original.
2746  return getQualifiedType(result, split.Quals);
2747}
2748
2749/// getVariableArrayType - Returns a non-unique reference to the type for a
2750/// variable array of the specified element type.
2751QualType ASTContext::getVariableArrayType(QualType EltTy,
2752                                          Expr *NumElts,
2753                                          ArrayType::ArraySizeModifier ASM,
2754                                          unsigned IndexTypeQuals,
2755                                          SourceRange Brackets) const {
2756  // Since we don't unique expressions, it isn't possible to unique VLA's
2757  // that have an expression provided for their size.
2758  QualType Canon;
2759
2760  // Be sure to pull qualifiers off the element type.
2761  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2762    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2763    Canon = getVariableArrayType(QualType(canonSplit.Ty, 0), NumElts, ASM,
2764                                 IndexTypeQuals, Brackets);
2765    Canon = getQualifiedType(Canon, canonSplit.Quals);
2766  }
2767
2768  VariableArrayType *New = new(*this, TypeAlignment)
2769    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
2770
2771  VariableArrayTypes.push_back(New);
2772  Types.push_back(New);
2773  return QualType(New, 0);
2774}
2775
2776/// getDependentSizedArrayType - Returns a non-unique reference to
2777/// the type for a dependently-sized array of the specified element
2778/// type.
2779QualType ASTContext::getDependentSizedArrayType(QualType elementType,
2780                                                Expr *numElements,
2781                                                ArrayType::ArraySizeModifier ASM,
2782                                                unsigned elementTypeQuals,
2783                                                SourceRange brackets) const {
2784  assert((!numElements || numElements->isTypeDependent() ||
2785          numElements->isValueDependent()) &&
2786         "Size must be type- or value-dependent!");
2787
2788  // Dependently-sized array types that do not have a specified number
2789  // of elements will have their sizes deduced from a dependent
2790  // initializer.  We do no canonicalization here at all, which is okay
2791  // because they can't be used in most locations.
2792  if (!numElements) {
2793    DependentSizedArrayType *newType
2794      = new (*this, TypeAlignment)
2795          DependentSizedArrayType(*this, elementType, QualType(),
2796                                  numElements, ASM, elementTypeQuals,
2797                                  brackets);
2798    Types.push_back(newType);
2799    return QualType(newType, 0);
2800  }
2801
2802  // Otherwise, we actually build a new type every time, but we
2803  // also build a canonical type.
2804
2805  SplitQualType canonElementType = getCanonicalType(elementType).split();
2806
2807  void *insertPos = nullptr;
2808  llvm::FoldingSetNodeID ID;
2809  DependentSizedArrayType::Profile(ID, *this,
2810                                   QualType(canonElementType.Ty, 0),
2811                                   ASM, elementTypeQuals, numElements);
2812
2813  // Look for an existing type with these properties.
2814  DependentSizedArrayType *canonTy =
2815    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2816
2817  // If we don't have one, build one.
2818  if (!canonTy) {
2819    canonTy = new (*this, TypeAlignment)
2820      DependentSizedArrayType(*this, QualType(canonElementType.Ty, 0),
2821                              QualType(), numElements, ASM, elementTypeQuals,
2822                              brackets);
2823    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
2824    Types.push_back(canonTy);
2825  }
2826
2827  // Apply qualifiers from the element type to the array.
2828  QualType canon = getQualifiedType(QualType(canonTy,0),
2829                                    canonElementType.Quals);
2830
2831  // If we didn't need extra canonicalization for the element type or the size
2832  // expression, then just use that as our result.
2833  if (QualType(canonElementType.Ty, 0) == elementType &&
2834      canonTy->getSizeExpr() == numElements)
2835    return canon;
2836
2837  // Otherwise, we need to build a type which follows the spelling
2838  // of the element type.
2839  DependentSizedArrayType *sugaredType
2840    = new (*this, TypeAlignment)
2841        DependentSizedArrayType(*this, elementType, canon, numElements,
2842                                ASM, elementTypeQuals, brackets);
2843  Types.push_back(sugaredType);
2844  return QualType(sugaredType, 0);
2845}
2846
2847QualType ASTContext::getIncompleteArrayType(QualType elementType,
2848                                            ArrayType::ArraySizeModifier ASM,
2849                                            unsigned elementTypeQuals) const {
2850  llvm::FoldingSetNodeID ID;
2851  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
2852
2853  void *insertPos = nullptr;
2854  if (IncompleteArrayType *iat =
2855       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
2856    return QualType(iat, 0);
2857
2858  // If the element type isn't canonical, this won't be a canonical type
2859  // either, so fill in the canonical type field.  We also have to pull
2860  // qualifiers off the element type.
2861  QualType canon;
2862
2863  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
2864    SplitQualType canonSplit = getCanonicalType(elementType).split();
2865    canon = getIncompleteArrayType(QualType(canonSplit.Ty, 0),
2866                                   ASM, elementTypeQuals);
2867    canon = getQualifiedType(canon, canonSplit.Quals);
2868
2869    // Get the new insert position for the node we care about.
2870    IncompleteArrayType *existing =
2871      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2872    assert(!existing && "Shouldn't be in the map!"); (void) existing;
2873  }
2874
2875  IncompleteArrayType *newType = new (*this, TypeAlignment)
2876    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
2877
2878  IncompleteArrayTypes.InsertNode(newType, insertPos);
2879  Types.push_back(newType);
2880  return QualType(newType, 0);
2881}
2882
2883/// getVectorType - Return the unique reference to a vector type of
2884/// the specified element type and size. VectorType must be a built-in type.
2885QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
2886                                   VectorType::VectorKind VecKind) const {
2887  assert(vecType->isBuiltinType());
2888
2889  // Check if we've already instantiated a vector of this type.
2890  llvm::FoldingSetNodeID ID;
2891  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
2892
2893  void *InsertPos = nullptr;
2894  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2895    return QualType(VTP, 0);
2896
2897  // If the element type isn't canonical, this won't be a canonical type either,
2898  // so fill in the canonical type field.
2899  QualType Canonical;
2900  if (!vecType.isCanonical()) {
2901    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
2902
2903    // Get the new insert position for the node we care about.
2904    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2905    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2906  }
2907  VectorType *New = new (*this, TypeAlignment)
2908    VectorType(vecType, NumElts, Canonical, VecKind);
2909  VectorTypes.InsertNode(New, InsertPos);
2910  Types.push_back(New);
2911  return QualType(New, 0);
2912}
2913
2914/// getExtVectorType - Return the unique reference to an extended vector type of
2915/// the specified element type and size. VectorType must be a built-in type.
2916QualType
2917ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
2918  assert(vecType->isBuiltinType() || vecType->isDependentType());
2919
2920  // Check if we've already instantiated a vector of this type.
2921  llvm::FoldingSetNodeID ID;
2922  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
2923                      VectorType::GenericVector);
2924  void *InsertPos = nullptr;
2925  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2926    return QualType(VTP, 0);
2927
2928  // If the element type isn't canonical, this won't be a canonical type either,
2929  // so fill in the canonical type field.
2930  QualType Canonical;
2931  if (!vecType.isCanonical()) {
2932    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
2933
2934    // Get the new insert position for the node we care about.
2935    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2936    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2937  }
2938  ExtVectorType *New = new (*this, TypeAlignment)
2939    ExtVectorType(vecType, NumElts, Canonical);
2940  VectorTypes.InsertNode(New, InsertPos);
2941  Types.push_back(New);
2942  return QualType(New, 0);
2943}
2944
2945QualType
2946ASTContext::getDependentSizedExtVectorType(QualType vecType,
2947                                           Expr *SizeExpr,
2948                                           SourceLocation AttrLoc) const {
2949  llvm::FoldingSetNodeID ID;
2950  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
2951                                       SizeExpr);
2952
2953  void *InsertPos = nullptr;
2954  DependentSizedExtVectorType *Canon
2955    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2956  DependentSizedExtVectorType *New;
2957  if (Canon) {
2958    // We already have a canonical version of this array type; use it as
2959    // the canonical type for a newly-built type.
2960    New = new (*this, TypeAlignment)
2961      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
2962                                  SizeExpr, AttrLoc);
2963  } else {
2964    QualType CanonVecTy = getCanonicalType(vecType);
2965    if (CanonVecTy == vecType) {
2966      New = new (*this, TypeAlignment)
2967        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
2968                                    AttrLoc);
2969
2970      DependentSizedExtVectorType *CanonCheck
2971        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2972      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
2973      (void)CanonCheck;
2974      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
2975    } else {
2976      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
2977                                                      SourceLocation());
2978      New = new (*this, TypeAlignment)
2979        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2980    }
2981  }
2982
2983  Types.push_back(New);
2984  return QualType(New, 0);
2985}
2986
2987/// \brief Determine whether \p T is canonical as the result type of a function.
2988static bool isCanonicalResultType(QualType T) {
2989  return T.isCanonical() &&
2990         (T.getObjCLifetime() == Qualifiers::OCL_None ||
2991          T.getObjCLifetime() == Qualifiers::OCL_ExplicitNone);
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  // Unique functions, to guarantee there is only one function of a particular
3000  // structure.
3001  llvm::FoldingSetNodeID ID;
3002  FunctionNoProtoType::Profile(ID, ResultTy, Info);
3003
3004  void *InsertPos = nullptr;
3005  if (FunctionNoProtoType *FT =
3006        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
3007    return QualType(FT, 0);
3008
3009  QualType Canonical;
3010  if (!isCanonicalResultType(ResultTy)) {
3011    Canonical =
3012      getFunctionNoProtoType(getCanonicalFunctionResultType(ResultTy), Info);
3013
3014    // Get the new insert position for the node we care about.
3015    FunctionNoProtoType *NewIP =
3016      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
3017    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
3018  }
3019
3020  FunctionNoProtoType *New = new (*this, TypeAlignment)
3021    FunctionNoProtoType(ResultTy, Canonical, Info);
3022  Types.push_back(New);
3023  FunctionNoProtoTypes.InsertNode(New, InsertPos);
3024  return QualType(New, 0);
3025}
3026
3027CanQualType
3028ASTContext::getCanonicalFunctionResultType(QualType ResultType) const {
3029  CanQualType CanResultType = getCanonicalType(ResultType);
3030
3031  // Canonical result types do not have ARC lifetime qualifiers.
3032  if (CanResultType.getQualifiers().hasObjCLifetime()) {
3033    Qualifiers Qs = CanResultType.getQualifiers();
3034    Qs.removeObjCLifetime();
3035    return CanQualType::CreateUnsafe(
3036             getQualifiedType(CanResultType.getUnqualifiedType(), Qs));
3037  }
3038
3039  return CanResultType;
3040}
3041
3042QualType
3043ASTContext::getFunctionType(QualType ResultTy, ArrayRef<QualType> ArgArray,
3044                            const FunctionProtoType::ExtProtoInfo &EPI) const {
3045  size_t NumArgs = ArgArray.size();
3046
3047  // Unique functions, to guarantee there is only one function of a particular
3048  // structure.
3049  llvm::FoldingSetNodeID ID;
3050  FunctionProtoType::Profile(ID, ResultTy, ArgArray.begin(), NumArgs, EPI,
3051                             *this);
3052
3053  void *InsertPos = nullptr;
3054  if (FunctionProtoType *FTP =
3055        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
3056    return QualType(FTP, 0);
3057
3058  // Determine whether the type being created is already canonical or not.
3059  bool isCanonical =
3060    EPI.ExceptionSpec.Type == EST_None && isCanonicalResultType(ResultTy) &&
3061    !EPI.HasTrailingReturn;
3062  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
3063    if (!ArgArray[i].isCanonicalAsParam())
3064      isCanonical = false;
3065
3066  // If this type isn't canonical, get the canonical version of it.
3067  // The exception spec is not part of the canonical type.
3068  QualType Canonical;
3069  if (!isCanonical) {
3070    SmallVector<QualType, 16> CanonicalArgs;
3071    CanonicalArgs.reserve(NumArgs);
3072    for (unsigned i = 0; i != NumArgs; ++i)
3073      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
3074
3075    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
3076    CanonicalEPI.HasTrailingReturn = false;
3077    CanonicalEPI.ExceptionSpec = FunctionProtoType::ExceptionSpecInfo();
3078
3079    // Adjust the canonical function result type.
3080    CanQualType CanResultTy = getCanonicalFunctionResultType(ResultTy);
3081    Canonical = getFunctionType(CanResultTy, CanonicalArgs, CanonicalEPI);
3082
3083    // Get the new insert position for the node we care about.
3084    FunctionProtoType *NewIP =
3085      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
3086    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
3087  }
3088
3089  // FunctionProtoType objects are allocated with extra bytes after
3090  // them for three variable size arrays at the end:
3091  //  - parameter types
3092  //  - exception types
3093  //  - extended parameter information
3094  // Instead of the exception types, there could be a noexcept
3095  // expression, or information used to resolve the exception
3096  // specification.
3097  size_t Size = sizeof(FunctionProtoType) +
3098                NumArgs * sizeof(QualType);
3099
3100  if (EPI.ExceptionSpec.Type == EST_Dynamic) {
3101    Size += EPI.ExceptionSpec.Exceptions.size() * sizeof(QualType);
3102  } else if (EPI.ExceptionSpec.Type == EST_ComputedNoexcept) {
3103    Size += sizeof(Expr*);
3104  } else if (EPI.ExceptionSpec.Type == EST_Uninstantiated) {
3105    Size += 2 * sizeof(FunctionDecl*);
3106  } else if (EPI.ExceptionSpec.Type == EST_Unevaluated) {
3107    Size += sizeof(FunctionDecl*);
3108  }
3109
3110  // Put the ExtParameterInfos last.  If all were equal, it would make
3111  // more sense to put these before the exception specification, because
3112  // it's much easier to skip past them compared to the elaborate switch
3113  // required to skip the exception specification.  However, all is not
3114  // equal; ExtParameterInfos are used to model very uncommon features,
3115  // and it's better not to burden the more common paths.
3116  if (EPI.ExtParameterInfos) {
3117    Size += NumArgs * sizeof(FunctionProtoType::ExtParameterInfo);
3118  }
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  SmallVector<TemplateArgument, 4> ArgVec;
3398  ArgVec.reserve(Args.size());
3399  for (const TemplateArgumentLoc &Arg : Args.arguments())
3400    ArgVec.push_back(Arg.getArgument());
3401
3402  return getTemplateSpecializationType(Template, ArgVec, Underlying);
3403}
3404
3405#ifndef NDEBUG
3406static bool hasAnyPackExpansions(ArrayRef<TemplateArgument> Args) {
3407  for (const TemplateArgument &Arg : Args)
3408    if (Arg.isPackExpansion())
3409      return true;
3410
3411  return true;
3412}
3413#endif
3414
3415QualType
3416ASTContext::getTemplateSpecializationType(TemplateName Template,
3417                                          ArrayRef<TemplateArgument> Args,
3418                                          QualType Underlying) const {
3419  assert(!Template.getAsDependentTemplateName() &&
3420         "No dependent template names here!");
3421  // Look through qualified template names.
3422  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
3423    Template = TemplateName(QTN->getTemplateDecl());
3424
3425  bool IsTypeAlias =
3426    Template.getAsTemplateDecl() &&
3427    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
3428  QualType CanonType;
3429  if (!Underlying.isNull())
3430    CanonType = getCanonicalType(Underlying);
3431  else {
3432    // We can get here with an alias template when the specialization contains
3433    // a pack expansion that does not match up with a parameter pack.
3434    assert((!IsTypeAlias || hasAnyPackExpansions(Args)) &&
3435           "Caller must compute aliased type");
3436    IsTypeAlias = false;
3437    CanonType = getCanonicalTemplateSpecializationType(Template, Args);
3438  }
3439
3440  // Allocate the (non-canonical) template specialization type, but don't
3441  // try to unique it: these types typically have location information that
3442  // we don't unique and don't want to lose.
3443  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
3444                       sizeof(TemplateArgument) * Args.size() +
3445                       (IsTypeAlias? sizeof(QualType) : 0),
3446                       TypeAlignment);
3447  TemplateSpecializationType *Spec
3448    = new (Mem) TemplateSpecializationType(Template, Args, CanonType,
3449                                         IsTypeAlias ? Underlying : QualType());
3450
3451  Types.push_back(Spec);
3452  return QualType(Spec, 0);
3453}
3454
3455QualType ASTContext::getCanonicalTemplateSpecializationType(
3456    TemplateName Template, ArrayRef<TemplateArgument> Args) const {
3457  assert(!Template.getAsDependentTemplateName() &&
3458         "No dependent template names here!");
3459
3460  // Look through qualified template names.
3461  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
3462    Template = TemplateName(QTN->getTemplateDecl());
3463
3464  // Build the canonical template specialization type.
3465  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
3466  SmallVector<TemplateArgument, 4> CanonArgs;
3467  unsigned NumArgs = Args.size();
3468  CanonArgs.reserve(NumArgs);
3469  for (const TemplateArgument &Arg : Args)
3470    CanonArgs.push_back(getCanonicalTemplateArgument(Arg));
3471
3472  // Determine whether this canonical template specialization type already
3473  // exists.
3474  llvm::FoldingSetNodeID ID;
3475  TemplateSpecializationType::Profile(ID, CanonTemplate,
3476                                      CanonArgs, *this);
3477
3478  void *InsertPos = nullptr;
3479  TemplateSpecializationType *Spec
3480    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3481
3482  if (!Spec) {
3483    // Allocate a new canonical template specialization type.
3484    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
3485                          sizeof(TemplateArgument) * NumArgs),
3486                         TypeAlignment);
3487    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
3488                                                CanonArgs,
3489                                                QualType(), QualType());
3490    Types.push_back(Spec);
3491    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
3492  }
3493
3494  assert(Spec->isDependentType() &&
3495         "Non-dependent template-id type must have a canonical type");
3496  return QualType(Spec, 0);
3497}
3498
3499QualType
3500ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
3501                              NestedNameSpecifier *NNS,
3502                              QualType NamedType) const {
3503  llvm::FoldingSetNodeID ID;
3504  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
3505
3506  void *InsertPos = nullptr;
3507  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
3508  if (T)
3509    return QualType(T, 0);
3510
3511  QualType Canon = NamedType;
3512  if (!Canon.isCanonical()) {
3513    Canon = getCanonicalType(NamedType);
3514    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
3515    assert(!CheckT && "Elaborated canonical type broken");
3516    (void)CheckT;
3517  }
3518
3519  T = new (*this, TypeAlignment) ElaboratedType(Keyword, NNS, NamedType, Canon);
3520  Types.push_back(T);
3521  ElaboratedTypes.InsertNode(T, InsertPos);
3522  return QualType(T, 0);
3523}
3524
3525QualType
3526ASTContext::getParenType(QualType InnerType) const {
3527  llvm::FoldingSetNodeID ID;
3528  ParenType::Profile(ID, InnerType);
3529
3530  void *InsertPos = nullptr;
3531  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
3532  if (T)
3533    return QualType(T, 0);
3534
3535  QualType Canon = InnerType;
3536  if (!Canon.isCanonical()) {
3537    Canon = getCanonicalType(InnerType);
3538    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
3539    assert(!CheckT && "Paren canonical type broken");
3540    (void)CheckT;
3541  }
3542
3543  T = new (*this, TypeAlignment) ParenType(InnerType, Canon);
3544  Types.push_back(T);
3545  ParenTypes.InsertNode(T, InsertPos);
3546  return QualType(T, 0);
3547}
3548
3549QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
3550                                          NestedNameSpecifier *NNS,
3551                                          const IdentifierInfo *Name,
3552                                          QualType Canon) const {
3553  if (Canon.isNull()) {
3554    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
3555    ElaboratedTypeKeyword CanonKeyword = Keyword;
3556    if (Keyword == ETK_None)
3557      CanonKeyword = ETK_Typename;
3558
3559    if (CanonNNS != NNS || CanonKeyword != Keyword)
3560      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
3561  }
3562
3563  llvm::FoldingSetNodeID ID;
3564  DependentNameType::Profile(ID, Keyword, NNS, Name);
3565
3566  void *InsertPos = nullptr;
3567  DependentNameType *T
3568    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
3569  if (T)
3570    return QualType(T, 0);
3571
3572  T = new (*this, TypeAlignment) DependentNameType(Keyword, NNS, Name, Canon);
3573  Types.push_back(T);
3574  DependentNameTypes.InsertNode(T, InsertPos);
3575  return QualType(T, 0);
3576}
3577
3578QualType
3579ASTContext::getDependentTemplateSpecializationType(
3580                                 ElaboratedTypeKeyword Keyword,
3581                                 NestedNameSpecifier *NNS,
3582                                 const IdentifierInfo *Name,
3583                                 const TemplateArgumentListInfo &Args) const {
3584  // TODO: avoid this copy
3585  SmallVector<TemplateArgument, 16> ArgCopy;
3586  for (unsigned I = 0, E = Args.size(); I != E; ++I)
3587    ArgCopy.push_back(Args[I].getArgument());
3588  return getDependentTemplateSpecializationType(Keyword, NNS, Name, ArgCopy);
3589}
3590
3591QualType
3592ASTContext::getDependentTemplateSpecializationType(
3593                                 ElaboratedTypeKeyword Keyword,
3594                                 NestedNameSpecifier *NNS,
3595                                 const IdentifierInfo *Name,
3596                                 ArrayRef<TemplateArgument> Args) const {
3597  assert((!NNS || NNS->isDependent()) &&
3598         "nested-name-specifier must be dependent");
3599
3600  llvm::FoldingSetNodeID ID;
3601  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
3602                                               Name, Args);
3603
3604  void *InsertPos = nullptr;
3605  DependentTemplateSpecializationType *T
3606    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3607  if (T)
3608    return QualType(T, 0);
3609
3610  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
3611
3612  ElaboratedTypeKeyword CanonKeyword = Keyword;
3613  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
3614
3615  bool AnyNonCanonArgs = false;
3616  unsigned NumArgs = Args.size();
3617  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
3618  for (unsigned I = 0; I != NumArgs; ++I) {
3619    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
3620    if (!CanonArgs[I].structurallyEquals(Args[I]))
3621      AnyNonCanonArgs = true;
3622  }
3623
3624  QualType Canon;
3625  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
3626    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
3627                                                   Name,
3628                                                   CanonArgs);
3629
3630    // Find the insert position again.
3631    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3632  }
3633
3634  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
3635                        sizeof(TemplateArgument) * NumArgs),
3636                       TypeAlignment);
3637  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
3638                                                    Name, Args, Canon);
3639  Types.push_back(T);
3640  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
3641  return QualType(T, 0);
3642}
3643
3644QualType ASTContext::getPackExpansionType(QualType Pattern,
3645                                          Optional<unsigned> NumExpansions) {
3646  llvm::FoldingSetNodeID ID;
3647  PackExpansionType::Profile(ID, Pattern, NumExpansions);
3648
3649  assert(Pattern->containsUnexpandedParameterPack() &&
3650         "Pack expansions must expand one or more parameter packs");
3651  void *InsertPos = nullptr;
3652  PackExpansionType *T
3653    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3654  if (T)
3655    return QualType(T, 0);
3656
3657  QualType Canon;
3658  if (!Pattern.isCanonical()) {
3659    Canon = getCanonicalType(Pattern);
3660    // The canonical type might not contain an unexpanded parameter pack, if it
3661    // contains an alias template specialization which ignores one of its
3662    // parameters.
3663    if (Canon->containsUnexpandedParameterPack()) {
3664      Canon = getPackExpansionType(Canon, NumExpansions);
3665
3666      // Find the insert position again, in case we inserted an element into
3667      // PackExpansionTypes and invalidated our insert position.
3668      PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3669    }
3670  }
3671
3672  T = new (*this, TypeAlignment)
3673      PackExpansionType(Pattern, Canon, NumExpansions);
3674  Types.push_back(T);
3675  PackExpansionTypes.InsertNode(T, InsertPos);
3676  return QualType(T, 0);
3677}
3678
3679/// CmpProtocolNames - Comparison predicate for sorting protocols
3680/// alphabetically.
3681static int CmpProtocolNames(ObjCProtocolDecl *const *LHS,
3682                            ObjCProtocolDecl *const *RHS) {
3683  return DeclarationName::compare((*LHS)->getDeclName(), (*RHS)->getDeclName());
3684}
3685
3686static bool areSortedAndUniqued(ArrayRef<ObjCProtocolDecl *> Protocols) {
3687  if (Protocols.empty()) return true;
3688
3689  if (Protocols[0]->getCanonicalDecl() != Protocols[0])
3690    return false;
3691
3692  for (unsigned i = 1; i != Protocols.size(); ++i)
3693    if (CmpProtocolNames(&Protocols[i - 1], &Protocols[i]) >= 0 ||
3694        Protocols[i]->getCanonicalDecl() != Protocols[i])
3695      return false;
3696  return true;
3697}
3698
3699static void
3700SortAndUniqueProtocols(SmallVectorImpl<ObjCProtocolDecl *> &Protocols) {
3701  // Sort protocols, keyed by name.
3702  llvm::array_pod_sort(Protocols.begin(), Protocols.end(), CmpProtocolNames);
3703
3704  // Canonicalize.
3705  for (ObjCProtocolDecl *&P : Protocols)
3706    P = P->getCanonicalDecl();
3707
3708  // Remove duplicates.
3709  auto ProtocolsEnd = std::unique(Protocols.begin(), Protocols.end());
3710  Protocols.erase(ProtocolsEnd, Protocols.end());
3711}
3712
3713QualType ASTContext::getObjCObjectType(QualType BaseType,
3714                                       ObjCProtocolDecl * const *Protocols,
3715                                       unsigned NumProtocols) const {
3716  return getObjCObjectType(BaseType, { },
3717                           llvm::makeArrayRef(Protocols, NumProtocols),
3718                           /*isKindOf=*/false);
3719}
3720
3721QualType ASTContext::getObjCObjectType(
3722           QualType baseType,
3723           ArrayRef<QualType> typeArgs,
3724           ArrayRef<ObjCProtocolDecl *> protocols,
3725           bool isKindOf) const {
3726  // If the base type is an interface and there aren't any protocols or
3727  // type arguments to add, then the interface type will do just fine.
3728  if (typeArgs.empty() && protocols.empty() && !isKindOf &&
3729      isa<ObjCInterfaceType>(baseType))
3730    return baseType;
3731
3732  // Look in the folding set for an existing type.
3733  llvm::FoldingSetNodeID ID;
3734  ObjCObjectTypeImpl::Profile(ID, baseType, typeArgs, protocols, isKindOf);
3735  void *InsertPos = nullptr;
3736  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
3737    return QualType(QT, 0);
3738
3739  // Determine the type arguments to be used for canonicalization,
3740  // which may be explicitly specified here or written on the base
3741  // type.
3742  ArrayRef<QualType> effectiveTypeArgs = typeArgs;
3743  if (effectiveTypeArgs.empty()) {
3744    if (auto baseObject = baseType->getAs<ObjCObjectType>())
3745      effectiveTypeArgs = baseObject->getTypeArgs();
3746  }
3747
3748  // Build the canonical type, which has the canonical base type and a
3749  // sorted-and-uniqued list of protocols and the type arguments
3750  // canonicalized.
3751  QualType canonical;
3752  bool typeArgsAreCanonical = std::all_of(effectiveTypeArgs.begin(),
3753                                          effectiveTypeArgs.end(),
3754                                          [&](QualType type) {
3755                                            return type.isCanonical();
3756                                          });
3757  bool protocolsSorted = areSortedAndUniqued(protocols);
3758  if (!typeArgsAreCanonical || !protocolsSorted || !baseType.isCanonical()) {
3759    // Determine the canonical type arguments.
3760    ArrayRef<QualType> canonTypeArgs;
3761    SmallVector<QualType, 4> canonTypeArgsVec;
3762    if (!typeArgsAreCanonical) {
3763      canonTypeArgsVec.reserve(effectiveTypeArgs.size());
3764      for (auto typeArg : effectiveTypeArgs)
3765        canonTypeArgsVec.push_back(getCanonicalType(typeArg));
3766      canonTypeArgs = canonTypeArgsVec;
3767    } else {
3768      canonTypeArgs = effectiveTypeArgs;
3769    }
3770
3771    ArrayRef<ObjCProtocolDecl *> canonProtocols;
3772    SmallVector<ObjCProtocolDecl*, 8> canonProtocolsVec;
3773    if (!protocolsSorted) {
3774      canonProtocolsVec.append(protocols.begin(), protocols.end());
3775      SortAndUniqueProtocols(canonProtocolsVec);
3776      canonProtocols = canonProtocolsVec;
3777    } else {
3778      canonProtocols = protocols;
3779    }
3780
3781    canonical = getObjCObjectType(getCanonicalType(baseType), canonTypeArgs,
3782                                  canonProtocols, isKindOf);
3783
3784    // Regenerate InsertPos.
3785    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
3786  }
3787
3788  unsigned size = sizeof(ObjCObjectTypeImpl);
3789  size += typeArgs.size() * sizeof(QualType);
3790  size += protocols.size() * sizeof(ObjCProtocolDecl *);
3791  void *mem = Allocate(size, TypeAlignment);
3792  ObjCObjectTypeImpl *T =
3793    new (mem) ObjCObjectTypeImpl(canonical, baseType, typeArgs, protocols,
3794                                 isKindOf);
3795
3796  Types.push_back(T);
3797  ObjCObjectTypes.InsertNode(T, InsertPos);
3798  return QualType(T, 0);
3799}
3800
3801/// ObjCObjectAdoptsQTypeProtocols - Checks that protocols in IC's
3802/// protocol list adopt all protocols in QT's qualified-id protocol
3803/// list.
3804bool ASTContext::ObjCObjectAdoptsQTypeProtocols(QualType QT,
3805                                                ObjCInterfaceDecl *IC) {
3806  if (!QT->isObjCQualifiedIdType())
3807    return false;
3808
3809  if (const ObjCObjectPointerType *OPT = QT->getAs<ObjCObjectPointerType>()) {
3810    // If both the right and left sides have qualifiers.
3811    for (auto *Proto : OPT->quals()) {
3812      if (!IC->ClassImplementsProtocol(Proto, false))
3813        return false;
3814    }
3815    return true;
3816  }
3817  return false;
3818}
3819
3820/// QIdProtocolsAdoptObjCObjectProtocols - Checks that protocols in
3821/// QT's qualified-id protocol list adopt all protocols in IDecl's list
3822/// of protocols.
3823bool ASTContext::QIdProtocolsAdoptObjCObjectProtocols(QualType QT,
3824                                                ObjCInterfaceDecl *IDecl) {
3825  if (!QT->isObjCQualifiedIdType())
3826    return false;
3827  const ObjCObjectPointerType *OPT = QT->getAs<ObjCObjectPointerType>();
3828  if (!OPT)
3829    return false;
3830  if (!IDecl->hasDefinition())
3831    return false;
3832  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocols;
3833  CollectInheritedProtocols(IDecl, InheritedProtocols);
3834  if (InheritedProtocols.empty())
3835    return false;
3836  // Check that if every protocol in list of id<plist> conforms to a protcol
3837  // of IDecl's, then bridge casting is ok.
3838  bool Conforms = false;
3839  for (auto *Proto : OPT->quals()) {
3840    Conforms = false;
3841    for (auto *PI : InheritedProtocols) {
3842      if (ProtocolCompatibleWithProtocol(Proto, PI)) {
3843        Conforms = true;
3844        break;
3845      }
3846    }
3847    if (!Conforms)
3848      break;
3849  }
3850  if (Conforms)
3851    return true;
3852
3853  for (auto *PI : InheritedProtocols) {
3854    // If both the right and left sides have qualifiers.
3855    bool Adopts = false;
3856    for (auto *Proto : OPT->quals()) {
3857      // return 'true' if 'PI' is in the inheritance hierarchy of Proto
3858      if ((Adopts = ProtocolCompatibleWithProtocol(PI, Proto)))
3859        break;
3860    }
3861    if (!Adopts)
3862      return false;
3863  }
3864  return true;
3865}
3866
3867/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
3868/// the given object type.
3869QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
3870  llvm::FoldingSetNodeID ID;
3871  ObjCObjectPointerType::Profile(ID, ObjectT);
3872
3873  void *InsertPos = nullptr;
3874  if (ObjCObjectPointerType *QT =
3875              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
3876    return QualType(QT, 0);
3877
3878  // Find the canonical object type.
3879  QualType Canonical;
3880  if (!ObjectT.isCanonical()) {
3881    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
3882
3883    // Regenerate InsertPos.
3884    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
3885  }
3886
3887  // No match.
3888  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
3889  ObjCObjectPointerType *QType =
3890    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
3891
3892  Types.push_back(QType);
3893  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
3894  return QualType(QType, 0);
3895}
3896
3897/// getObjCInterfaceType - Return the unique reference to the type for the
3898/// specified ObjC interface decl. The list of protocols is optional.
3899QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
3900                                          ObjCInterfaceDecl *PrevDecl) const {
3901  if (Decl->TypeForDecl)
3902    return QualType(Decl->TypeForDecl, 0);
3903
3904  if (PrevDecl) {
3905    assert(PrevDecl->TypeForDecl && "previous decl has no TypeForDecl");
3906    Decl->TypeForDecl = PrevDecl->TypeForDecl;
3907    return QualType(PrevDecl->TypeForDecl, 0);
3908  }
3909
3910  // Prefer the definition, if there is one.
3911  if (const ObjCInterfaceDecl *Def = Decl->getDefinition())
3912    Decl = Def;
3913
3914  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
3915  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
3916  Decl->TypeForDecl = T;
3917  Types.push_back(T);
3918  return QualType(T, 0);
3919}
3920
3921/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
3922/// TypeOfExprType AST's (since expression's are never shared). For example,
3923/// multiple declarations that refer to "typeof(x)" all contain different
3924/// DeclRefExpr's. This doesn't effect the type checker, since it operates
3925/// on canonical type's (which are always unique).
3926QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
3927  TypeOfExprType *toe;
3928  if (tofExpr->isTypeDependent()) {
3929    llvm::FoldingSetNodeID ID;
3930    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
3931
3932    void *InsertPos = nullptr;
3933    DependentTypeOfExprType *Canon
3934      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
3935    if (Canon) {
3936      // We already have a "canonical" version of an identical, dependent
3937      // typeof(expr) type. Use that as our canonical type.
3938      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
3939                                          QualType((TypeOfExprType*)Canon, 0));
3940    } else {
3941      // Build a new, canonical typeof(expr) type.
3942      Canon
3943        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
3944      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
3945      toe = Canon;
3946    }
3947  } else {
3948    QualType Canonical = getCanonicalType(tofExpr->getType());
3949    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
3950  }
3951  Types.push_back(toe);
3952  return QualType(toe, 0);
3953}
3954
3955/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
3956/// TypeOfType nodes. The only motivation to unique these nodes would be
3957/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
3958/// an issue. This doesn't affect the type checker, since it operates
3959/// on canonical types (which are always unique).
3960QualType ASTContext::getTypeOfType(QualType tofType) const {
3961  QualType Canonical = getCanonicalType(tofType);
3962  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
3963  Types.push_back(tot);
3964  return QualType(tot, 0);
3965}
3966
3967/// \brief Unlike many "get<Type>" functions, we don't unique DecltypeType
3968/// nodes. This would never be helpful, since each such type has its own
3969/// expression, and would not give a significant memory saving, since there
3970/// is an Expr tree under each such type.
3971QualType ASTContext::getDecltypeType(Expr *e, QualType UnderlyingType) const {
3972  DecltypeType *dt;
3973
3974  // C++11 [temp.type]p2:
3975  //   If an expression e involves a template parameter, decltype(e) denotes a
3976  //   unique dependent type. Two such decltype-specifiers refer to the same
3977  //   type only if their expressions are equivalent (14.5.6.1).
3978  if (e->isInstantiationDependent()) {
3979    llvm::FoldingSetNodeID ID;
3980    DependentDecltypeType::Profile(ID, *this, e);
3981
3982    void *InsertPos = nullptr;
3983    DependentDecltypeType *Canon
3984      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
3985    if (!Canon) {
3986      // Build a new, canonical typeof(expr) type.
3987      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
3988      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
3989    }
3990    dt = new (*this, TypeAlignment)
3991        DecltypeType(e, UnderlyingType, QualType((DecltypeType *)Canon, 0));
3992  } else {
3993    dt = new (*this, TypeAlignment)
3994        DecltypeType(e, UnderlyingType, getCanonicalType(UnderlyingType));
3995  }
3996  Types.push_back(dt);
3997  return QualType(dt, 0);
3998}
3999
4000/// getUnaryTransformationType - We don't unique these, since the memory
4001/// savings are minimal and these are rare.
4002QualType ASTContext::getUnaryTransformType(QualType BaseType,
4003                                           QualType UnderlyingType,
4004                                           UnaryTransformType::UTTKind Kind)
4005    const {
4006  UnaryTransformType *ut = nullptr;
4007
4008  if (BaseType->isDependentType()) {
4009    // Look in the folding set for an existing type.
4010    llvm::FoldingSetNodeID ID;
4011    DependentUnaryTransformType::Profile(ID, getCanonicalType(BaseType), Kind);
4012
4013    void *InsertPos = nullptr;
4014    DependentUnaryTransformType *Canon
4015      = DependentUnaryTransformTypes.FindNodeOrInsertPos(ID, InsertPos);
4016
4017    if (!Canon) {
4018      // Build a new, canonical __underlying_type(type) type.
4019      Canon = new (*this, TypeAlignment)
4020             DependentUnaryTransformType(*this, getCanonicalType(BaseType),
4021                                         Kind);
4022      DependentUnaryTransformTypes.InsertNode(Canon, InsertPos);
4023    }
4024    ut = new (*this, TypeAlignment) UnaryTransformType (BaseType,
4025                                                        QualType(), Kind,
4026                                                        QualType(Canon, 0));
4027  } else {
4028    QualType CanonType = getCanonicalType(UnderlyingType);
4029    ut = new (*this, TypeAlignment) UnaryTransformType (BaseType,
4030                                                        UnderlyingType, Kind,
4031                                                        CanonType);
4032  }
4033  Types.push_back(ut);
4034  return QualType(ut, 0);
4035}
4036
4037/// getAutoType - Return the uniqued reference to the 'auto' type which has been
4038/// deduced to the given type, or to the canonical undeduced 'auto' type, or the
4039/// canonical deduced-but-dependent 'auto' type.
4040QualType ASTContext::getAutoType(QualType DeducedType, AutoTypeKeyword Keyword,
4041                                 bool IsDependent) const {
4042  if (DeducedType.isNull() && Keyword == AutoTypeKeyword::Auto && !IsDependent)
4043    return getAutoDeductType();
4044
4045  // Look in the folding set for an existing type.
4046  void *InsertPos = nullptr;
4047  llvm::FoldingSetNodeID ID;
4048  AutoType::Profile(ID, DeducedType, Keyword, IsDependent);
4049  if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
4050    return QualType(AT, 0);
4051
4052  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType,
4053                                                     Keyword,
4054                                                     IsDependent);
4055  Types.push_back(AT);
4056  if (InsertPos)
4057    AutoTypes.InsertNode(AT, InsertPos);
4058  return QualType(AT, 0);
4059}
4060
4061/// getAtomicType - Return the uniqued reference to the atomic type for
4062/// the given value type.
4063QualType ASTContext::getAtomicType(QualType T) const {
4064  // Unique pointers, to guarantee there is only one pointer of a particular
4065  // structure.
4066  llvm::FoldingSetNodeID ID;
4067  AtomicType::Profile(ID, T);
4068
4069  void *InsertPos = nullptr;
4070  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
4071    return QualType(AT, 0);
4072
4073  // If the atomic value type isn't canonical, this won't be a canonical type
4074  // either, so fill in the canonical type field.
4075  QualType Canonical;
4076  if (!T.isCanonical()) {
4077    Canonical = getAtomicType(getCanonicalType(T));
4078
4079    // Get the new insert position for the node we care about.
4080    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
4081    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
4082  }
4083  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
4084  Types.push_back(New);
4085  AtomicTypes.InsertNode(New, InsertPos);
4086  return QualType(New, 0);
4087}
4088
4089/// getAutoDeductType - Get type pattern for deducing against 'auto'.
4090QualType ASTContext::getAutoDeductType() const {
4091  if (AutoDeductTy.isNull())
4092    AutoDeductTy = QualType(
4093      new (*this, TypeAlignment) AutoType(QualType(), AutoTypeKeyword::Auto,
4094                                          /*dependent*/false),
4095      0);
4096  return AutoDeductTy;
4097}
4098
4099/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
4100QualType ASTContext::getAutoRRefDeductType() const {
4101  if (AutoRRefDeductTy.isNull())
4102    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
4103  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
4104  return AutoRRefDeductTy;
4105}
4106
4107/// getTagDeclType - Return the unique reference to the type for the
4108/// specified TagDecl (struct/union/class/enum) decl.
4109QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
4110  assert (Decl);
4111  // FIXME: What is the design on getTagDeclType when it requires casting
4112  // away const?  mutable?
4113  return getTypeDeclType(const_cast<TagDecl*>(Decl));
4114}
4115
4116/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
4117/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
4118/// needs to agree with the definition in <stddef.h>.
4119CanQualType ASTContext::getSizeType() const {
4120  return getFromTargetType(Target->getSizeType());
4121}
4122
4123/// getIntMaxType - Return the unique type for "intmax_t" (C99 7.18.1.5).
4124CanQualType ASTContext::getIntMaxType() const {
4125  return getFromTargetType(Target->getIntMaxType());
4126}
4127
4128/// getUIntMaxType - Return the unique type for "uintmax_t" (C99 7.18.1.5).
4129CanQualType ASTContext::getUIntMaxType() const {
4130  return getFromTargetType(Target->getUIntMaxType());
4131}
4132
4133/// getSignedWCharType - Return the type of "signed wchar_t".
4134/// Used when in C++, as a GCC extension.
4135QualType ASTContext::getSignedWCharType() const {
4136  // FIXME: derive from "Target" ?
4137  return WCharTy;
4138}
4139
4140/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
4141/// Used when in C++, as a GCC extension.
4142QualType ASTContext::getUnsignedWCharType() const {
4143  // FIXME: derive from "Target" ?
4144  return UnsignedIntTy;
4145}
4146
4147QualType ASTContext::getIntPtrType() const {
4148  return getFromTargetType(Target->getIntPtrType());
4149}
4150
4151QualType ASTContext::getUIntPtrType() const {
4152  return getCorrespondingUnsignedType(getIntPtrType());
4153}
4154
4155/// getPointerDiffType - Return the unique type for "ptrdiff_t" (C99 7.17)
4156/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
4157QualType ASTContext::getPointerDiffType() const {
4158  return getFromTargetType(Target->getPtrDiffType(0));
4159}
4160
4161/// \brief Return the unique type for "pid_t" defined in
4162/// <sys/types.h>. We need this to compute the correct type for vfork().
4163QualType ASTContext::getProcessIDType() const {
4164  return getFromTargetType(Target->getProcessIDType());
4165}
4166
4167//===----------------------------------------------------------------------===//
4168//                              Type Operators
4169//===----------------------------------------------------------------------===//
4170
4171CanQualType ASTContext::getCanonicalParamType(QualType T) const {
4172  // Push qualifiers into arrays, and then discard any remaining
4173  // qualifiers.
4174  T = getCanonicalType(T);
4175  T = getVariableArrayDecayedType(T);
4176  const Type *Ty = T.getTypePtr();
4177  QualType Result;
4178  if (isa<ArrayType>(Ty)) {
4179    Result = getArrayDecayedType(QualType(Ty,0));
4180  } else if (isa<FunctionType>(Ty)) {
4181    Result = getPointerType(QualType(Ty, 0));
4182  } else {
4183    Result = QualType(Ty, 0);
4184  }
4185
4186  return CanQualType::CreateUnsafe(Result);
4187}
4188
4189QualType ASTContext::getUnqualifiedArrayType(QualType type,
4190                                             Qualifiers &quals) {
4191  SplitQualType splitType = type.getSplitUnqualifiedType();
4192
4193  // FIXME: getSplitUnqualifiedType() actually walks all the way to
4194  // the unqualified desugared type and then drops it on the floor.
4195  // We then have to strip that sugar back off with
4196  // getUnqualifiedDesugaredType(), which is silly.
4197  const ArrayType *AT =
4198    dyn_cast<ArrayType>(splitType.Ty->getUnqualifiedDesugaredType());
4199
4200  // If we don't have an array, just use the results in splitType.
4201  if (!AT) {
4202    quals = splitType.Quals;
4203    return QualType(splitType.Ty, 0);
4204  }
4205
4206  // Otherwise, recurse on the array's element type.
4207  QualType elementType = AT->getElementType();
4208  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
4209
4210  // If that didn't change the element type, AT has no qualifiers, so we
4211  // can just use the results in splitType.
4212  if (elementType == unqualElementType) {
4213    assert(quals.empty()); // from the recursive call
4214    quals = splitType.Quals;
4215    return QualType(splitType.Ty, 0);
4216  }
4217
4218  // Otherwise, add in the qualifiers from the outermost type, then
4219  // build the type back up.
4220  quals.addConsistentQualifiers(splitType.Quals);
4221
4222  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
4223    return getConstantArrayType(unqualElementType, CAT->getSize(),
4224                                CAT->getSizeModifier(), 0);
4225  }
4226
4227  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
4228    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
4229  }
4230
4231  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
4232    return getVariableArrayType(unqualElementType,
4233                                VAT->getSizeExpr(),
4234                                VAT->getSizeModifier(),
4235                                VAT->getIndexTypeCVRQualifiers(),
4236                                VAT->getBracketsRange());
4237  }
4238
4239  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
4240  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
4241                                    DSAT->getSizeModifier(), 0,
4242                                    SourceRange());
4243}
4244
4245/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
4246/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
4247/// they point to and return true. If T1 and T2 aren't pointer types
4248/// or pointer-to-member types, or if they are not similar at this
4249/// level, returns false and leaves T1 and T2 unchanged. Top-level
4250/// qualifiers on T1 and T2 are ignored. This function will typically
4251/// be called in a loop that successively "unwraps" pointer and
4252/// pointer-to-member types to compare them at each level.
4253bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
4254  const PointerType *T1PtrType = T1->getAs<PointerType>(),
4255                    *T2PtrType = T2->getAs<PointerType>();
4256  if (T1PtrType && T2PtrType) {
4257    T1 = T1PtrType->getPointeeType();
4258    T2 = T2PtrType->getPointeeType();
4259    return true;
4260  }
4261
4262  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
4263                          *T2MPType = T2->getAs<MemberPointerType>();
4264  if (T1MPType && T2MPType &&
4265      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
4266                             QualType(T2MPType->getClass(), 0))) {
4267    T1 = T1MPType->getPointeeType();
4268    T2 = T2MPType->getPointeeType();
4269    return true;
4270  }
4271
4272  if (getLangOpts().ObjC1) {
4273    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
4274                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
4275    if (T1OPType && T2OPType) {
4276      T1 = T1OPType->getPointeeType();
4277      T2 = T2OPType->getPointeeType();
4278      return true;
4279    }
4280  }
4281
4282  // FIXME: Block pointers, too?
4283
4284  return false;
4285}
4286
4287DeclarationNameInfo
4288ASTContext::getNameForTemplate(TemplateName Name,
4289                               SourceLocation NameLoc) const {
4290  switch (Name.getKind()) {
4291  case TemplateName::QualifiedTemplate:
4292  case TemplateName::Template:
4293    // DNInfo work in progress: CHECKME: what about DNLoc?
4294    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
4295                               NameLoc);
4296
4297  case TemplateName::OverloadedTemplate: {
4298    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
4299    // DNInfo work in progress: CHECKME: what about DNLoc?
4300    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
4301  }
4302
4303  case TemplateName::DependentTemplate: {
4304    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
4305    DeclarationName DName;
4306    if (DTN->isIdentifier()) {
4307      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
4308      return DeclarationNameInfo(DName, NameLoc);
4309    } else {
4310      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
4311      // DNInfo work in progress: FIXME: source locations?
4312      DeclarationNameLoc DNLoc;
4313      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
4314      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
4315      return DeclarationNameInfo(DName, NameLoc, DNLoc);
4316    }
4317  }
4318
4319  case TemplateName::SubstTemplateTemplateParm: {
4320    SubstTemplateTemplateParmStorage *subst
4321      = Name.getAsSubstTemplateTemplateParm();
4322    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
4323                               NameLoc);
4324  }
4325
4326  case TemplateName::SubstTemplateTemplateParmPack: {
4327    SubstTemplateTemplateParmPackStorage *subst
4328      = Name.getAsSubstTemplateTemplateParmPack();
4329    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
4330                               NameLoc);
4331  }
4332  }
4333
4334  llvm_unreachable("bad template name kind!");
4335}
4336
4337TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
4338  switch (Name.getKind()) {
4339  case TemplateName::QualifiedTemplate:
4340  case TemplateName::Template: {
4341    TemplateDecl *Template = Name.getAsTemplateDecl();
4342    if (TemplateTemplateParmDecl *TTP
4343          = dyn_cast<TemplateTemplateParmDecl>(Template))
4344      Template = getCanonicalTemplateTemplateParmDecl(TTP);
4345
4346    // The canonical template name is the canonical template declaration.
4347    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
4348  }
4349
4350  case TemplateName::OverloadedTemplate:
4351    llvm_unreachable("cannot canonicalize overloaded template");
4352
4353  case TemplateName::DependentTemplate: {
4354    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
4355    assert(DTN && "Non-dependent template names must refer to template decls.");
4356    return DTN->CanonicalTemplateName;
4357  }
4358
4359  case TemplateName::SubstTemplateTemplateParm: {
4360    SubstTemplateTemplateParmStorage *subst
4361      = Name.getAsSubstTemplateTemplateParm();
4362    return getCanonicalTemplateName(subst->getReplacement());
4363  }
4364
4365  case TemplateName::SubstTemplateTemplateParmPack: {
4366    SubstTemplateTemplateParmPackStorage *subst
4367                                  = Name.getAsSubstTemplateTemplateParmPack();
4368    TemplateTemplateParmDecl *canonParameter
4369      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
4370    TemplateArgument canonArgPack
4371      = getCanonicalTemplateArgument(subst->getArgumentPack());
4372    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
4373  }
4374  }
4375
4376  llvm_unreachable("bad template name!");
4377}
4378
4379bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
4380  X = getCanonicalTemplateName(X);
4381  Y = getCanonicalTemplateName(Y);
4382  return X.getAsVoidPointer() == Y.getAsVoidPointer();
4383}
4384
4385TemplateArgument
4386ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
4387  switch (Arg.getKind()) {
4388    case TemplateArgument::Null:
4389      return Arg;
4390
4391    case TemplateArgument::Expression:
4392      return Arg;
4393
4394    case TemplateArgument::Declaration: {
4395      ValueDecl *D = cast<ValueDecl>(Arg.getAsDecl()->getCanonicalDecl());
4396      return TemplateArgument(D, Arg.getParamTypeForDecl());
4397    }
4398
4399    case TemplateArgument::NullPtr:
4400      return TemplateArgument(getCanonicalType(Arg.getNullPtrType()),
4401                              /*isNullPtr*/true);
4402
4403    case TemplateArgument::Template:
4404      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
4405
4406    case TemplateArgument::TemplateExpansion:
4407      return TemplateArgument(getCanonicalTemplateName(
4408                                         Arg.getAsTemplateOrTemplatePattern()),
4409                              Arg.getNumTemplateExpansions());
4410
4411    case TemplateArgument::Integral:
4412      return TemplateArgument(Arg, getCanonicalType(Arg.getIntegralType()));
4413
4414    case TemplateArgument::Type:
4415      return TemplateArgument(getCanonicalType(Arg.getAsType()));
4416
4417    case TemplateArgument::Pack: {
4418      if (Arg.pack_size() == 0)
4419        return Arg;
4420
4421      TemplateArgument *CanonArgs
4422        = new (*this) TemplateArgument[Arg.pack_size()];
4423      unsigned Idx = 0;
4424      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
4425                                        AEnd = Arg.pack_end();
4426           A != AEnd; (void)++A, ++Idx)
4427        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
4428
4429      return TemplateArgument(llvm::makeArrayRef(CanonArgs, Arg.pack_size()));
4430    }
4431  }
4432
4433  // Silence GCC warning
4434  llvm_unreachable("Unhandled template argument kind");
4435}
4436
4437NestedNameSpecifier *
4438ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
4439  if (!NNS)
4440    return nullptr;
4441
4442  switch (NNS->getKind()) {
4443  case NestedNameSpecifier::Identifier:
4444    // Canonicalize the prefix but keep the identifier the same.
4445    return NestedNameSpecifier::Create(*this,
4446                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
4447                                       NNS->getAsIdentifier());
4448
4449  case NestedNameSpecifier::Namespace:
4450    // A namespace is canonical; build a nested-name-specifier with
4451    // this namespace and no prefix.
4452    return NestedNameSpecifier::Create(*this, nullptr,
4453                                 NNS->getAsNamespace()->getOriginalNamespace());
4454
4455  case NestedNameSpecifier::NamespaceAlias:
4456    // A namespace is canonical; build a nested-name-specifier with
4457    // this namespace and no prefix.
4458    return NestedNameSpecifier::Create(*this, nullptr,
4459                                    NNS->getAsNamespaceAlias()->getNamespace()
4460                                                      ->getOriginalNamespace());
4461
4462  case NestedNameSpecifier::TypeSpec:
4463  case NestedNameSpecifier::TypeSpecWithTemplate: {
4464    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
4465
4466    // If we have some kind of dependent-named type (e.g., "typename T::type"),
4467    // break it apart into its prefix and identifier, then reconsititute those
4468    // as the canonical nested-name-specifier. This is required to canonicalize
4469    // a dependent nested-name-specifier involving typedefs of dependent-name
4470    // types, e.g.,
4471    //   typedef typename T::type T1;
4472    //   typedef typename T1::type T2;
4473    if (const DependentNameType *DNT = T->getAs<DependentNameType>())
4474      return NestedNameSpecifier::Create(*this, DNT->getQualifier(),
4475                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
4476
4477    // Otherwise, just canonicalize the type, and force it to be a TypeSpec.
4478    // FIXME: Why are TypeSpec and TypeSpecWithTemplate distinct in the
4479    // first place?
4480    return NestedNameSpecifier::Create(*this, nullptr, false,
4481                                       const_cast<Type *>(T.getTypePtr()));
4482  }
4483
4484  case NestedNameSpecifier::Global:
4485  case NestedNameSpecifier::Super:
4486    // The global specifier and __super specifer are canonical and unique.
4487    return NNS;
4488  }
4489
4490  llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
4491}
4492
4493const ArrayType *ASTContext::getAsArrayType(QualType T) const {
4494  // Handle the non-qualified case efficiently.
4495  if (!T.hasLocalQualifiers()) {
4496    // Handle the common positive case fast.
4497    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
4498      return AT;
4499  }
4500
4501  // Handle the common negative case fast.
4502  if (!isa<ArrayType>(T.getCanonicalType()))
4503    return nullptr;
4504
4505  // Apply any qualifiers from the array type to the element type.  This
4506  // implements C99 6.7.3p8: "If the specification of an array type includes
4507  // any type qualifiers, the element type is so qualified, not the array type."
4508
4509  // If we get here, we either have type qualifiers on the type, or we have
4510  // sugar such as a typedef in the way.  If we have type qualifiers on the type
4511  // we must propagate them down into the element type.
4512
4513  SplitQualType split = T.getSplitDesugaredType();
4514  Qualifiers qs = split.Quals;
4515
4516  // If we have a simple case, just return now.
4517  const ArrayType *ATy = dyn_cast<ArrayType>(split.Ty);
4518  if (!ATy || qs.empty())
4519    return ATy;
4520
4521  // Otherwise, we have an array and we have qualifiers on it.  Push the
4522  // qualifiers into the array element type and return a new array type.
4523  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
4524
4525  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
4526    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
4527                                                CAT->getSizeModifier(),
4528                                           CAT->getIndexTypeCVRQualifiers()));
4529  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
4530    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
4531                                                  IAT->getSizeModifier(),
4532                                           IAT->getIndexTypeCVRQualifiers()));
4533
4534  if (const DependentSizedArrayType *DSAT
4535        = dyn_cast<DependentSizedArrayType>(ATy))
4536    return cast<ArrayType>(
4537                     getDependentSizedArrayType(NewEltTy,
4538                                                DSAT->getSizeExpr(),
4539                                                DSAT->getSizeModifier(),
4540                                              DSAT->getIndexTypeCVRQualifiers(),
4541                                                DSAT->getBracketsRange()));
4542
4543  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
4544  return cast<ArrayType>(getVariableArrayType(NewEltTy,
4545                                              VAT->getSizeExpr(),
4546                                              VAT->getSizeModifier(),
4547                                              VAT->getIndexTypeCVRQualifiers(),
4548                                              VAT->getBracketsRange()));
4549}
4550
4551QualType ASTContext::getAdjustedParameterType(QualType T) const {
4552  if (T->isArrayType() || T->isFunctionType())
4553    return getDecayedType(T);
4554  return T;
4555}
4556
4557QualType ASTContext::getSignatureParameterType(QualType T) const {
4558  T = getVariableArrayDecayedType(T);
4559  T = getAdjustedParameterType(T);
4560  return T.getUnqualifiedType();
4561}
4562
4563QualType ASTContext::getExceptionObjectType(QualType T) const {
4564  // C++ [except.throw]p3:
4565  //   A throw-expression initializes a temporary object, called the exception
4566  //   object, the type of which is determined by removing any top-level
4567  //   cv-qualifiers from the static type of the operand of throw and adjusting
4568  //   the type from "array of T" or "function returning T" to "pointer to T"
4569  //   or "pointer to function returning T", [...]
4570  T = getVariableArrayDecayedType(T);
4571  if (T->isArrayType() || T->isFunctionType())
4572    T = getDecayedType(T);
4573  return T.getUnqualifiedType();
4574}
4575
4576/// getArrayDecayedType - Return the properly qualified result of decaying the
4577/// specified array type to a pointer.  This operation is non-trivial when
4578/// handling typedefs etc.  The canonical type of "T" must be an array type,
4579/// this returns a pointer to a properly qualified element of the array.
4580///
4581/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
4582QualType ASTContext::getArrayDecayedType(QualType Ty) const {
4583  // Get the element type with 'getAsArrayType' so that we don't lose any
4584  // typedefs in the element type of the array.  This also handles propagation
4585  // of type qualifiers from the array type into the element type if present
4586  // (C99 6.7.3p8).
4587  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
4588  assert(PrettyArrayType && "Not an array type!");
4589
4590  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
4591
4592  // int x[restrict 4] ->  int *restrict
4593  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
4594}
4595
4596QualType ASTContext::getBaseElementType(const ArrayType *array) const {
4597  return getBaseElementType(array->getElementType());
4598}
4599
4600QualType ASTContext::getBaseElementType(QualType type) const {
4601  Qualifiers qs;
4602  while (true) {
4603    SplitQualType split = type.getSplitDesugaredType();
4604    const ArrayType *array = split.Ty->getAsArrayTypeUnsafe();
4605    if (!array) break;
4606
4607    type = array->getElementType();
4608    qs.addConsistentQualifiers(split.Quals);
4609  }
4610
4611  return getQualifiedType(type, qs);
4612}
4613
4614/// getConstantArrayElementCount - Returns number of constant array elements.
4615uint64_t
4616ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
4617  uint64_t ElementCount = 1;
4618  do {
4619    ElementCount *= CA->getSize().getZExtValue();
4620    CA = dyn_cast_or_null<ConstantArrayType>(
4621      CA->getElementType()->getAsArrayTypeUnsafe());
4622  } while (CA);
4623  return ElementCount;
4624}
4625
4626/// getFloatingRank - Return a relative rank for floating point types.
4627/// This routine will assert if passed a built-in type that isn't a float.
4628static FloatingRank getFloatingRank(QualType T) {
4629  if (const ComplexType *CT = T->getAs<ComplexType>())
4630    return getFloatingRank(CT->getElementType());
4631
4632  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
4633  switch (T->getAs<BuiltinType>()->getKind()) {
4634  default: llvm_unreachable("getFloatingRank(): not a floating type");
4635  case BuiltinType::Half:       return HalfRank;
4636  case BuiltinType::Float:      return FloatRank;
4637  case BuiltinType::Double:     return DoubleRank;
4638  case BuiltinType::LongDouble: return LongDoubleRank;
4639  case BuiltinType::Float128:   return Float128Rank;
4640  }
4641}
4642
4643/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
4644/// point or a complex type (based on typeDomain/typeSize).
4645/// 'typeDomain' is a real floating point or complex type.
4646/// 'typeSize' is a real floating point or complex type.
4647QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
4648                                                       QualType Domain) const {
4649  FloatingRank EltRank = getFloatingRank(Size);
4650  if (Domain->isComplexType()) {
4651    switch (EltRank) {
4652    case HalfRank: llvm_unreachable("Complex half is not supported");
4653    case FloatRank:      return FloatComplexTy;
4654    case DoubleRank:     return DoubleComplexTy;
4655    case LongDoubleRank: return LongDoubleComplexTy;
4656    case Float128Rank:   return Float128ComplexTy;
4657    }
4658  }
4659
4660  assert(Domain->isRealFloatingType() && "Unknown domain!");
4661  switch (EltRank) {
4662  case HalfRank:       return HalfTy;
4663  case FloatRank:      return FloatTy;
4664  case DoubleRank:     return DoubleTy;
4665  case LongDoubleRank: return LongDoubleTy;
4666  case Float128Rank:   return Float128Ty;
4667  }
4668  llvm_unreachable("getFloatingRank(): illegal value for rank");
4669}
4670
4671/// getFloatingTypeOrder - Compare the rank of the two specified floating
4672/// point types, ignoring the domain of the type (i.e. 'double' ==
4673/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
4674/// LHS < RHS, return -1.
4675int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
4676  FloatingRank LHSR = getFloatingRank(LHS);
4677  FloatingRank RHSR = getFloatingRank(RHS);
4678
4679  if (LHSR == RHSR)
4680    return 0;
4681  if (LHSR > RHSR)
4682    return 1;
4683  return -1;
4684}
4685
4686/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
4687/// routine will assert if passed a built-in type that isn't an integer or enum,
4688/// or if it is not canonicalized.
4689unsigned ASTContext::getIntegerRank(const Type *T) const {
4690  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
4691
4692  switch (cast<BuiltinType>(T)->getKind()) {
4693  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
4694  case BuiltinType::Bool:
4695    return 1 + (getIntWidth(BoolTy) << 3);
4696  case BuiltinType::Char_S:
4697  case BuiltinType::Char_U:
4698  case BuiltinType::SChar:
4699  case BuiltinType::UChar:
4700    return 2 + (getIntWidth(CharTy) << 3);
4701  case BuiltinType::Short:
4702  case BuiltinType::UShort:
4703    return 3 + (getIntWidth(ShortTy) << 3);
4704  case BuiltinType::Int:
4705  case BuiltinType::UInt:
4706    return 4 + (getIntWidth(IntTy) << 3);
4707  case BuiltinType::Long:
4708  case BuiltinType::ULong:
4709    return 5 + (getIntWidth(LongTy) << 3);
4710  case BuiltinType::LongLong:
4711  case BuiltinType::ULongLong:
4712    return 6 + (getIntWidth(LongLongTy) << 3);
4713  case BuiltinType::Int128:
4714  case BuiltinType::UInt128:
4715    return 7 + (getIntWidth(Int128Ty) << 3);
4716  }
4717}
4718
4719/// \brief Whether this is a promotable bitfield reference according
4720/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
4721///
4722/// \returns the type this bit-field will promote to, or NULL if no
4723/// promotion occurs.
4724QualType ASTContext::isPromotableBitField(Expr *E) const {
4725  if (E->isTypeDependent() || E->isValueDependent())
4726    return QualType();
4727
4728  // FIXME: We should not do this unless E->refersToBitField() is true. This
4729  // matters in C where getSourceBitField() will find bit-fields for various
4730  // cases where the source expression is not a bit-field designator.
4731
4732  FieldDecl *Field = E->getSourceBitField(); // FIXME: conditional bit-fields?
4733  if (!Field)
4734    return QualType();
4735
4736  QualType FT = Field->getType();
4737
4738  uint64_t BitWidth = Field->getBitWidthValue(*this);
4739  uint64_t IntSize = getTypeSize(IntTy);
4740  // C++ [conv.prom]p5:
4741  //   A prvalue for an integral bit-field can be converted to a prvalue of type
4742  //   int if int can represent all the values of the bit-field; otherwise, it
4743  //   can be converted to unsigned int if unsigned int can represent all the
4744  //   values of the bit-field. If the bit-field is larger yet, no integral
4745  //   promotion applies to it.
4746  // C11 6.3.1.1/2:
4747  //   [For a bit-field of type _Bool, int, signed int, or unsigned int:]
4748  //   If an int can represent all values of the original type (as restricted by
4749  //   the width, for a bit-field), the value is converted to an int; otherwise,
4750  //   it is converted to an unsigned int.
4751  //
4752  // FIXME: C does not permit promotion of a 'long : 3' bitfield to int.
4753  //        We perform that promotion here to match GCC and C++.
4754  if (BitWidth < IntSize)
4755    return IntTy;
4756
4757  if (BitWidth == IntSize)
4758    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
4759
4760  // Types bigger than int are not subject to promotions, and therefore act
4761  // like the base type. GCC has some weird bugs in this area that we
4762  // deliberately do not follow (GCC follows a pre-standard resolution to
4763  // C's DR315 which treats bit-width as being part of the type, and this leaks
4764  // into their semantics in some cases).
4765  return QualType();
4766}
4767
4768/// getPromotedIntegerType - Returns the type that Promotable will
4769/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
4770/// integer type.
4771QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
4772  assert(!Promotable.isNull());
4773  assert(Promotable->isPromotableIntegerType());
4774  if (const EnumType *ET = Promotable->getAs<EnumType>())
4775    return ET->getDecl()->getPromotionType();
4776
4777  if (const BuiltinType *BT = Promotable->getAs<BuiltinType>()) {
4778    // C++ [conv.prom]: A prvalue of type char16_t, char32_t, or wchar_t
4779    // (3.9.1) can be converted to a prvalue of the first of the following
4780    // types that can represent all the values of its underlying type:
4781    // int, unsigned int, long int, unsigned long int, long long int, or
4782    // unsigned long long int [...]
4783    // FIXME: Is there some better way to compute this?
4784    if (BT->getKind() == BuiltinType::WChar_S ||
4785        BT->getKind() == BuiltinType::WChar_U ||
4786        BT->getKind() == BuiltinType::Char16 ||
4787        BT->getKind() == BuiltinType::Char32) {
4788      bool FromIsSigned = BT->getKind() == BuiltinType::WChar_S;
4789      uint64_t FromSize = getTypeSize(BT);
4790      QualType PromoteTypes[] = { IntTy, UnsignedIntTy, LongTy, UnsignedLongTy,
4791                                  LongLongTy, UnsignedLongLongTy };
4792      for (size_t Idx = 0; Idx < llvm::array_lengthof(PromoteTypes); ++Idx) {
4793        uint64_t ToSize = getTypeSize(PromoteTypes[Idx]);
4794        if (FromSize < ToSize ||
4795            (FromSize == ToSize &&
4796             FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType()))
4797          return PromoteTypes[Idx];
4798      }
4799      llvm_unreachable("char type should fit into long long");
4800    }
4801  }
4802
4803  // At this point, we should have a signed or unsigned integer type.
4804  if (Promotable->isSignedIntegerType())
4805    return IntTy;
4806  uint64_t PromotableSize = getIntWidth(Promotable);
4807  uint64_t IntSize = getIntWidth(IntTy);
4808  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
4809  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
4810}
4811
4812/// \brief Recurses in pointer/array types until it finds an objc retainable
4813/// type and returns its ownership.
4814Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
4815  while (!T.isNull()) {
4816    if (T.getObjCLifetime() != Qualifiers::OCL_None)
4817      return T.getObjCLifetime();
4818    if (T->isArrayType())
4819      T = getBaseElementType(T);
4820    else if (const PointerType *PT = T->getAs<PointerType>())
4821      T = PT->getPointeeType();
4822    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4823      T = RT->getPointeeType();
4824    else
4825      break;
4826  }
4827
4828  return Qualifiers::OCL_None;
4829}
4830
4831static const Type *getIntegerTypeForEnum(const EnumType *ET) {
4832  // Incomplete enum types are not treated as integer types.
4833  // FIXME: In C++, enum types are never integer types.
4834  if (ET->getDecl()->isComplete() && !ET->getDecl()->isScoped())
4835    return ET->getDecl()->getIntegerType().getTypePtr();
4836  return nullptr;
4837}
4838
4839/// getIntegerTypeOrder - Returns the highest ranked integer type:
4840/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
4841/// LHS < RHS, return -1.
4842int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
4843  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
4844  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
4845
4846  // Unwrap enums to their underlying type.
4847  if (const EnumType *ET = dyn_cast<EnumType>(LHSC))
4848    LHSC = getIntegerTypeForEnum(ET);
4849  if (const EnumType *ET = dyn_cast<EnumType>(RHSC))
4850    RHSC = getIntegerTypeForEnum(ET);
4851
4852  if (LHSC == RHSC) return 0;
4853
4854  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
4855  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
4856
4857  unsigned LHSRank = getIntegerRank(LHSC);
4858  unsigned RHSRank = getIntegerRank(RHSC);
4859
4860  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
4861    if (LHSRank == RHSRank) return 0;
4862    return LHSRank > RHSRank ? 1 : -1;
4863  }
4864
4865  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
4866  if (LHSUnsigned) {
4867    // If the unsigned [LHS] type is larger, return it.
4868    if (LHSRank >= RHSRank)
4869      return 1;
4870
4871    // If the signed type can represent all values of the unsigned type, it
4872    // wins.  Because we are dealing with 2's complement and types that are
4873    // powers of two larger than each other, this is always safe.
4874    return -1;
4875  }
4876
4877  // If the unsigned [RHS] type is larger, return it.
4878  if (RHSRank >= LHSRank)
4879    return -1;
4880
4881  // If the signed type can represent all values of the unsigned type, it
4882  // wins.  Because we are dealing with 2's complement and types that are
4883  // powers of two larger than each other, this is always safe.
4884  return 1;
4885}
4886
4887TypedefDecl *ASTContext::getCFConstantStringDecl() const {
4888  if (!CFConstantStringTypeDecl) {
4889    assert(!CFConstantStringTagDecl &&
4890           "tag and typedef should be initialized together");
4891    CFConstantStringTagDecl = buildImplicitRecord("__NSConstantString_tag");
4892    CFConstantStringTagDecl->startDefinition();
4893
4894    QualType FieldTypes[4];
4895    const char *FieldNames[4];
4896
4897    // const int *isa;
4898    FieldTypes[0] = getPointerType(IntTy.withConst());
4899    FieldNames[0] = "isa";
4900    // int flags;
4901    FieldTypes[1] = IntTy;
4902    FieldNames[1] = "flags";
4903    // const char *str;
4904    FieldTypes[2] = getPointerType(CharTy.withConst());
4905    FieldNames[2] = "str";
4906    // long length;
4907    FieldTypes[3] = LongTy;
4908    FieldNames[3] = "length";
4909
4910    // Create fields
4911    for (unsigned i = 0; i < 4; ++i) {
4912      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTagDecl,
4913                                           SourceLocation(),
4914                                           SourceLocation(),
4915                                           &Idents.get(FieldNames[i]),
4916                                           FieldTypes[i], /*TInfo=*/nullptr,
4917                                           /*BitWidth=*/nullptr,
4918                                           /*Mutable=*/false,
4919                                           ICIS_NoInit);
4920      Field->setAccess(AS_public);
4921      CFConstantStringTagDecl->addDecl(Field);
4922    }
4923
4924    CFConstantStringTagDecl->completeDefinition();
4925    // This type is designed to be compatible with NSConstantString, but cannot
4926    // use the same name, since NSConstantString is an interface.
4927    auto tagType = getTagDeclType(CFConstantStringTagDecl);
4928    CFConstantStringTypeDecl =
4929        buildImplicitTypedef(tagType, "__NSConstantString");
4930  }
4931
4932  return CFConstantStringTypeDecl;
4933}
4934
4935RecordDecl *ASTContext::getCFConstantStringTagDecl() const {
4936  if (!CFConstantStringTagDecl)
4937    getCFConstantStringDecl(); // Build the tag and the typedef.
4938  return CFConstantStringTagDecl;
4939}
4940
4941// getCFConstantStringType - Return the type used for constant CFStrings.
4942QualType ASTContext::getCFConstantStringType() const {
4943  return getTypedefType(getCFConstantStringDecl());
4944}
4945
4946QualType ASTContext::getObjCSuperType() const {
4947  if (ObjCSuperType.isNull()) {
4948    RecordDecl *ObjCSuperTypeDecl = buildImplicitRecord("objc_super");
4949    TUDecl->addDecl(ObjCSuperTypeDecl);
4950    ObjCSuperType = getTagDeclType(ObjCSuperTypeDecl);
4951  }
4952  return ObjCSuperType;
4953}
4954
4955void ASTContext::setCFConstantStringType(QualType T) {
4956  const TypedefType *TD = T->getAs<TypedefType>();
4957  assert(TD && "Invalid CFConstantStringType");
4958  CFConstantStringTypeDecl = cast<TypedefDecl>(TD->getDecl());
4959  auto TagType =
4960      CFConstantStringTypeDecl->getUnderlyingType()->getAs<RecordType>();
4961  assert(TagType && "Invalid CFConstantStringType");
4962  CFConstantStringTagDecl = TagType->getDecl();
4963}
4964
4965QualType ASTContext::getBlockDescriptorType() const {
4966  if (BlockDescriptorType)
4967    return getTagDeclType(BlockDescriptorType);
4968
4969  RecordDecl *RD;
4970  // FIXME: Needs the FlagAppleBlock bit.
4971  RD = buildImplicitRecord("__block_descriptor");
4972  RD->startDefinition();
4973
4974  QualType FieldTypes[] = {
4975    UnsignedLongTy,
4976    UnsignedLongTy,
4977  };
4978
4979  static const char *const FieldNames[] = {
4980    "reserved",
4981    "Size"
4982  };
4983
4984  for (size_t i = 0; i < 2; ++i) {
4985    FieldDecl *Field = FieldDecl::Create(
4986        *this, RD, SourceLocation(), SourceLocation(),
4987        &Idents.get(FieldNames[i]), FieldTypes[i], /*TInfo=*/nullptr,
4988        /*BitWidth=*/nullptr, /*Mutable=*/false, ICIS_NoInit);
4989    Field->setAccess(AS_public);
4990    RD->addDecl(Field);
4991  }
4992
4993  RD->completeDefinition();
4994
4995  BlockDescriptorType = RD;
4996
4997  return getTagDeclType(BlockDescriptorType);
4998}
4999
5000QualType ASTContext::getBlockDescriptorExtendedType() const {
5001  if (BlockDescriptorExtendedType)
5002    return getTagDeclType(BlockDescriptorExtendedType);
5003
5004  RecordDecl *RD;
5005  // FIXME: Needs the FlagAppleBlock bit.
5006  RD = buildImplicitRecord("__block_descriptor_withcopydispose");
5007  RD->startDefinition();
5008
5009  QualType FieldTypes[] = {
5010    UnsignedLongTy,
5011    UnsignedLongTy,
5012    getPointerType(VoidPtrTy),
5013    getPointerType(VoidPtrTy)
5014  };
5015
5016  static const char *const FieldNames[] = {
5017    "reserved",
5018    "Size",
5019    "CopyFuncPtr",
5020    "DestroyFuncPtr"
5021  };
5022
5023  for (size_t i = 0; i < 4; ++i) {
5024    FieldDecl *Field = FieldDecl::Create(
5025        *this, RD, SourceLocation(), SourceLocation(),
5026        &Idents.get(FieldNames[i]), FieldTypes[i], /*TInfo=*/nullptr,
5027        /*BitWidth=*/nullptr,
5028        /*Mutable=*/false, ICIS_NoInit);
5029    Field->setAccess(AS_public);
5030    RD->addDecl(Field);
5031  }
5032
5033  RD->completeDefinition();
5034
5035  BlockDescriptorExtendedType = RD;
5036  return getTagDeclType(BlockDescriptorExtendedType);
5037}
5038
5039/// BlockRequiresCopying - Returns true if byref variable "D" of type "Ty"
5040/// requires copy/dispose. Note that this must match the logic
5041/// in buildByrefHelpers.
5042bool ASTContext::BlockRequiresCopying(QualType Ty,
5043                                      const VarDecl *D) {
5044  if (const CXXRecordDecl *record = Ty->getAsCXXRecordDecl()) {
5045    const Expr *copyExpr = getBlockVarCopyInits(D);
5046    if (!copyExpr && record->hasTrivialDestructor()) return false;
5047
5048    return true;
5049  }
5050
5051  if (!Ty->isObjCRetainableType()) return false;
5052
5053  Qualifiers qs = Ty.getQualifiers();
5054
5055  // If we have lifetime, that dominates.
5056  if (Qualifiers::ObjCLifetime lifetime = qs.getObjCLifetime()) {
5057    switch (lifetime) {
5058      case Qualifiers::OCL_None: llvm_unreachable("impossible");
5059
5060      // These are just bits as far as the runtime is concerned.
5061      case Qualifiers::OCL_ExplicitNone:
5062      case Qualifiers::OCL_Autoreleasing:
5063        return false;
5064
5065      // Tell the runtime that this is ARC __weak, called by the
5066      // byref routines.
5067      case Qualifiers::OCL_Weak:
5068      // ARC __strong __block variables need to be retained.
5069      case Qualifiers::OCL_Strong:
5070        return true;
5071    }
5072    llvm_unreachable("fell out of lifetime switch!");
5073  }
5074  return (Ty->isBlockPointerType() || isObjCNSObjectType(Ty) ||
5075          Ty->isObjCObjectPointerType());
5076}
5077
5078bool ASTContext::getByrefLifetime(QualType Ty,
5079                              Qualifiers::ObjCLifetime &LifeTime,
5080                              bool &HasByrefExtendedLayout) const {
5081
5082  if (!getLangOpts().ObjC1 ||
5083      getLangOpts().getGC() != LangOptions::NonGC)
5084    return false;
5085
5086  HasByrefExtendedLayout = false;
5087  if (Ty->isRecordType()) {
5088    HasByrefExtendedLayout = true;
5089    LifeTime = Qualifiers::OCL_None;
5090  } else if ((LifeTime = Ty.getObjCLifetime())) {
5091    // Honor the ARC qualifiers.
5092  } else if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType()) {
5093    // The MRR rule.
5094    LifeTime = Qualifiers::OCL_ExplicitNone;
5095  } else {
5096    LifeTime = Qualifiers::OCL_None;
5097  }
5098  return true;
5099}
5100
5101TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
5102  if (!ObjCInstanceTypeDecl)
5103    ObjCInstanceTypeDecl =
5104        buildImplicitTypedef(getObjCIdType(), "instancetype");
5105  return ObjCInstanceTypeDecl;
5106}
5107
5108// This returns true if a type has been typedefed to BOOL:
5109// typedef <type> BOOL;
5110static bool isTypeTypedefedAsBOOL(QualType T) {
5111  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
5112    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
5113      return II->isStr("BOOL");
5114
5115  return false;
5116}
5117
5118/// getObjCEncodingTypeSize returns size of type for objective-c encoding
5119/// purpose.
5120CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
5121  if (!type->isIncompleteArrayType() && type->isIncompleteType())
5122    return CharUnits::Zero();
5123
5124  CharUnits sz = getTypeSizeInChars(type);
5125
5126  // Make all integer and enum types at least as large as an int
5127  if (sz.isPositive() && type->isIntegralOrEnumerationType())
5128    sz = std::max(sz, getTypeSizeInChars(IntTy));
5129  // Treat arrays as pointers, since that's how they're passed in.
5130  else if (type->isArrayType())
5131    sz = getTypeSizeInChars(VoidPtrTy);
5132  return sz;
5133}
5134
5135bool ASTContext::isMSStaticDataMemberInlineDefinition(const VarDecl *VD) const {
5136  return getTargetInfo().getCXXABI().isMicrosoft() &&
5137         VD->isStaticDataMember() &&
5138         VD->getType()->isIntegralOrEnumerationType() &&
5139         !VD->getFirstDecl()->isOutOfLine() && VD->getFirstDecl()->hasInit();
5140}
5141
5142ASTContext::InlineVariableDefinitionKind
5143ASTContext::getInlineVariableDefinitionKind(const VarDecl *VD) const {
5144  if (!VD->isInline())
5145    return InlineVariableDefinitionKind::None;
5146
5147  // In almost all cases, it's a weak definition.
5148  auto *First = VD->getFirstDecl();
5149  if (!First->isConstexpr() || First->isInlineSpecified() ||
5150      !VD->isStaticDataMember())
5151    return InlineVariableDefinitionKind::Weak;
5152
5153  // If there's a file-context declaration in this translation unit, it's a
5154  // non-discardable definition.
5155  for (auto *D : VD->redecls())
5156    if (D->getLexicalDeclContext()->isFileContext())
5157      return InlineVariableDefinitionKind::Strong;
5158
5159  // If we've not seen one yet, we don't know.
5160  return InlineVariableDefinitionKind::WeakUnknown;
5161}
5162
5163static inline
5164std::string charUnitsToString(const CharUnits &CU) {
5165  return llvm::itostr(CU.getQuantity());
5166}
5167
5168/// getObjCEncodingForBlock - Return the encoded type for this block
5169/// declaration.
5170std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
5171  std::string S;
5172
5173  const BlockDecl *Decl = Expr->getBlockDecl();
5174  QualType BlockTy =
5175      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
5176  // Encode result type.
5177  if (getLangOpts().EncodeExtendedBlockSig)
5178    getObjCEncodingForMethodParameter(
5179        Decl::OBJC_TQ_None, BlockTy->getAs<FunctionType>()->getReturnType(), S,
5180        true /*Extended*/);
5181  else
5182    getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getReturnType(), S);
5183  // Compute size of all parameters.
5184  // Start with computing size of a pointer in number of bytes.
5185  // FIXME: There might(should) be a better way of doing this computation!
5186  SourceLocation Loc;
5187  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
5188  CharUnits ParmOffset = PtrSize;
5189  for (auto PI : Decl->parameters()) {
5190    QualType PType = PI->getType();
5191    CharUnits sz = getObjCEncodingTypeSize(PType);
5192    if (sz.isZero())
5193      continue;
5194    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
5195    ParmOffset += sz;
5196  }
5197  // Size of the argument frame
5198  S += charUnitsToString(ParmOffset);
5199  // Block pointer and offset.
5200  S += "@?0";
5201
5202  // Argument types.
5203  ParmOffset = PtrSize;
5204  for (auto PVDecl : Decl->parameters()) {
5205    QualType PType = PVDecl->getOriginalType();
5206    if (const ArrayType *AT =
5207          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
5208      // Use array's original type only if it has known number of
5209      // elements.
5210      if (!isa<ConstantArrayType>(AT))
5211        PType = PVDecl->getType();
5212    } else if (PType->isFunctionType())
5213      PType = PVDecl->getType();
5214    if (getLangOpts().EncodeExtendedBlockSig)
5215      getObjCEncodingForMethodParameter(Decl::OBJC_TQ_None, PType,
5216                                      S, true /*Extended*/);
5217    else
5218      getObjCEncodingForType(PType, S);
5219    S += charUnitsToString(ParmOffset);
5220    ParmOffset += getObjCEncodingTypeSize(PType);
5221  }
5222
5223  return S;
5224}
5225
5226bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
5227                                                std::string& S) {
5228  // Encode result type.
5229  getObjCEncodingForType(Decl->getReturnType(), S);
5230  CharUnits ParmOffset;
5231  // Compute size of all parameters.
5232  for (auto PI : Decl->parameters()) {
5233    QualType PType = PI->getType();
5234    CharUnits sz = getObjCEncodingTypeSize(PType);
5235    if (sz.isZero())
5236      continue;
5237
5238    assert (sz.isPositive() &&
5239        "getObjCEncodingForFunctionDecl - Incomplete param type");
5240    ParmOffset += sz;
5241  }
5242  S += charUnitsToString(ParmOffset);
5243  ParmOffset = CharUnits::Zero();
5244
5245  // Argument types.
5246  for (auto PVDecl : Decl->parameters()) {
5247    QualType PType = PVDecl->getOriginalType();
5248    if (const ArrayType *AT =
5249          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
5250      // Use array's original type only if it has known number of
5251      // elements.
5252      if (!isa<ConstantArrayType>(AT))
5253        PType = PVDecl->getType();
5254    } else if (PType->isFunctionType())
5255      PType = PVDecl->getType();
5256    getObjCEncodingForType(PType, S);
5257    S += charUnitsToString(ParmOffset);
5258    ParmOffset += getObjCEncodingTypeSize(PType);
5259  }
5260
5261  return false;
5262}
5263
5264/// getObjCEncodingForMethodParameter - Return the encoded type for a single
5265/// method parameter or return type. If Extended, include class names and
5266/// block object types.
5267void ASTContext::getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
5268                                                   QualType T, std::string& S,
5269                                                   bool Extended) const {
5270  // Encode type qualifer, 'in', 'inout', etc. for the parameter.
5271  getObjCEncodingForTypeQualifier(QT, S);
5272  // Encode parameter type.
5273  getObjCEncodingForTypeImpl(T, S, true, true, nullptr,
5274                             true     /*OutermostType*/,
5275                             false    /*EncodingProperty*/,
5276                             false    /*StructField*/,
5277                             Extended /*EncodeBlockParameters*/,
5278                             Extended /*EncodeClassNames*/);
5279}
5280
5281/// getObjCEncodingForMethodDecl - Return the encoded type for this method
5282/// declaration.
5283bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
5284                                              std::string& S,
5285                                              bool Extended) const {
5286  // FIXME: This is not very efficient.
5287  // Encode return type.
5288  getObjCEncodingForMethodParameter(Decl->getObjCDeclQualifier(),
5289                                    Decl->getReturnType(), S, Extended);
5290  // Compute size of all parameters.
5291  // Start with computing size of a pointer in number of bytes.
5292  // FIXME: There might(should) be a better way of doing this computation!
5293  SourceLocation Loc;
5294  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
5295  // The first two arguments (self and _cmd) are pointers; account for
5296  // their size.
5297  CharUnits ParmOffset = 2 * PtrSize;
5298  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
5299       E = Decl->sel_param_end(); PI != E; ++PI) {
5300    QualType PType = (*PI)->getType();
5301    CharUnits sz = getObjCEncodingTypeSize(PType);
5302    if (sz.isZero())
5303      continue;
5304
5305    assert (sz.isPositive() &&
5306        "getObjCEncodingForMethodDecl - Incomplete param type");
5307    ParmOffset += sz;
5308  }
5309  S += charUnitsToString(ParmOffset);
5310  S += "@0:";
5311  S += charUnitsToString(PtrSize);
5312
5313  // Argument types.
5314  ParmOffset = 2 * PtrSize;
5315  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
5316       E = Decl->sel_param_end(); PI != E; ++PI) {
5317    const ParmVarDecl *PVDecl = *PI;
5318    QualType PType = PVDecl->getOriginalType();
5319    if (const ArrayType *AT =
5320          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
5321      // Use array's original type only if it has known number of
5322      // elements.
5323      if (!isa<ConstantArrayType>(AT))
5324        PType = PVDecl->getType();
5325    } else if (PType->isFunctionType())
5326      PType = PVDecl->getType();
5327    getObjCEncodingForMethodParameter(PVDecl->getObjCDeclQualifier(),
5328                                      PType, S, Extended);
5329    S += charUnitsToString(ParmOffset);
5330    ParmOffset += getObjCEncodingTypeSize(PType);
5331  }
5332
5333  return false;
5334}
5335
5336ObjCPropertyImplDecl *
5337ASTContext::getObjCPropertyImplDeclForPropertyDecl(
5338                                      const ObjCPropertyDecl *PD,
5339                                      const Decl *Container) const {
5340  if (!Container)
5341    return nullptr;
5342  if (const ObjCCategoryImplDecl *CID =
5343      dyn_cast<ObjCCategoryImplDecl>(Container)) {
5344    for (auto *PID : CID->property_impls())
5345      if (PID->getPropertyDecl() == PD)
5346        return PID;
5347  } else {
5348    const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
5349    for (auto *PID : OID->property_impls())
5350      if (PID->getPropertyDecl() == PD)
5351        return PID;
5352  }
5353  return nullptr;
5354}
5355
5356/// getObjCEncodingForPropertyDecl - Return the encoded type for this
5357/// property declaration. If non-NULL, Container must be either an
5358/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
5359/// NULL when getting encodings for protocol properties.
5360/// Property attributes are stored as a comma-delimited C string. The simple
5361/// attributes readonly and bycopy are encoded as single characters. The
5362/// parametrized attributes, getter=name, setter=name, and ivar=name, are
5363/// encoded as single characters, followed by an identifier. Property types
5364/// are also encoded as a parametrized attribute. The characters used to encode
5365/// these attributes are defined by the following enumeration:
5366/// @code
5367/// enum PropertyAttributes {
5368/// kPropertyReadOnly = 'R',   // property is read-only.
5369/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
5370/// kPropertyByref = '&',  // property is a reference to the value last assigned
5371/// kPropertyDynamic = 'D',    // property is dynamic
5372/// kPropertyGetter = 'G',     // followed by getter selector name
5373/// kPropertySetter = 'S',     // followed by setter selector name
5374/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
5375/// kPropertyType = 'T'              // followed by old-style type encoding.
5376/// kPropertyWeak = 'W'              // 'weak' property
5377/// kPropertyStrong = 'P'            // property GC'able
5378/// kPropertyNonAtomic = 'N'         // property non-atomic
5379/// };
5380/// @endcode
5381void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
5382                                                const Decl *Container,
5383                                                std::string& S) const {
5384  // Collect information from the property implementation decl(s).
5385  bool Dynamic = false;
5386  ObjCPropertyImplDecl *SynthesizePID = nullptr;
5387
5388  if (ObjCPropertyImplDecl *PropertyImpDecl =
5389      getObjCPropertyImplDeclForPropertyDecl(PD, Container)) {
5390    if (PropertyImpDecl->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
5391      Dynamic = true;
5392    else
5393      SynthesizePID = PropertyImpDecl;
5394  }
5395
5396  // FIXME: This is not very efficient.
5397  S = "T";
5398
5399  // Encode result type.
5400  // GCC has some special rules regarding encoding of properties which
5401  // closely resembles encoding of ivars.
5402  getObjCEncodingForPropertyType(PD->getType(), S);
5403
5404  if (PD->isReadOnly()) {
5405    S += ",R";
5406    if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_copy)
5407      S += ",C";
5408    if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_retain)
5409      S += ",&";
5410    if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_weak)
5411      S += ",W";
5412  } else {
5413    switch (PD->getSetterKind()) {
5414    case ObjCPropertyDecl::Assign: break;
5415    case ObjCPropertyDecl::Copy:   S += ",C"; break;
5416    case ObjCPropertyDecl::Retain: S += ",&"; break;
5417    case ObjCPropertyDecl::Weak:   S += ",W"; break;
5418    }
5419  }
5420
5421  // It really isn't clear at all what this means, since properties
5422  // are "dynamic by default".
5423  if (Dynamic)
5424    S += ",D";
5425
5426  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
5427    S += ",N";
5428
5429  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
5430    S += ",G";
5431    S += PD->getGetterName().getAsString();
5432  }
5433
5434  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
5435    S += ",S";
5436    S += PD->getSetterName().getAsString();
5437  }
5438
5439  if (SynthesizePID) {
5440    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
5441    S += ",V";
5442    S += OID->getNameAsString();
5443  }
5444
5445  // FIXME: OBJCGC: weak & strong
5446}
5447
5448/// getLegacyIntegralTypeEncoding -
5449/// Another legacy compatibility encoding: 32-bit longs are encoded as
5450/// 'l' or 'L' , but not always.  For typedefs, we need to use
5451/// 'i' or 'I' instead if encoding a struct field, or a pointer!
5452///
5453void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
5454  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
5455    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
5456      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
5457        PointeeTy = UnsignedIntTy;
5458      else
5459        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
5460          PointeeTy = IntTy;
5461    }
5462  }
5463}
5464
5465void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
5466                                        const FieldDecl *Field,
5467                                        QualType *NotEncodedT) const {
5468  // We follow the behavior of gcc, expanding structures which are
5469  // directly pointed to, and expanding embedded structures. Note that
5470  // these rules are sufficient to prevent recursive encoding of the
5471  // same type.
5472  getObjCEncodingForTypeImpl(T, S, true, true, Field,
5473                             true /* outermost type */, false, false,
5474                             false, false, false, NotEncodedT);
5475}
5476
5477void ASTContext::getObjCEncodingForPropertyType(QualType T,
5478                                                std::string& S) const {
5479  // Encode result type.
5480  // GCC has some special rules regarding encoding of properties which
5481  // closely resembles encoding of ivars.
5482  getObjCEncodingForTypeImpl(T, S, true, true, nullptr,
5483                             true /* outermost type */,
5484                             true /* encoding property */);
5485}
5486
5487static char getObjCEncodingForPrimitiveKind(const ASTContext *C,
5488                                            BuiltinType::Kind kind) {
5489    switch (kind) {
5490    case BuiltinType::Void:       return 'v';
5491    case BuiltinType::Bool:       return 'B';
5492    case BuiltinType::Char_U:
5493    case BuiltinType::UChar:      return 'C';
5494    case BuiltinType::Char16:
5495    case BuiltinType::UShort:     return 'S';
5496    case BuiltinType::Char32:
5497    case BuiltinType::UInt:       return 'I';
5498    case BuiltinType::ULong:
5499        return C->getTargetInfo().getLongWidth() == 32 ? 'L' : 'Q';
5500    case BuiltinType::UInt128:    return 'T';
5501    case BuiltinType::ULongLong:  return 'Q';
5502    case BuiltinType::Char_S:
5503    case BuiltinType::SChar:      return 'c';
5504    case BuiltinType::Short:      return 's';
5505    case BuiltinType::WChar_S:
5506    case BuiltinType::WChar_U:
5507    case BuiltinType::Int:        return 'i';
5508    case BuiltinType::Long:
5509      return C->getTargetInfo().getLongWidth() == 32 ? 'l' : 'q';
5510    case BuiltinType::LongLong:   return 'q';
5511    case BuiltinType::Int128:     return 't';
5512    case BuiltinType::Float:      return 'f';
5513    case BuiltinType::Double:     return 'd';
5514    case BuiltinType::LongDouble: return 'D';
5515    case BuiltinType::NullPtr:    return '*'; // like char*
5516
5517    case BuiltinType::Float128:
5518    case BuiltinType::Half:
5519      // FIXME: potentially need @encodes for these!
5520      return ' ';
5521
5522    case BuiltinType::ObjCId:
5523    case BuiltinType::ObjCClass:
5524    case BuiltinType::ObjCSel:
5525      llvm_unreachable("@encoding ObjC primitive type");
5526
5527    // OpenCL and placeholder types don't need @encodings.
5528#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
5529    case BuiltinType::Id:
5530#include "clang/Basic/OpenCLImageTypes.def"
5531    case BuiltinType::OCLEvent:
5532    case BuiltinType::OCLClkEvent:
5533    case BuiltinType::OCLQueue:
5534    case BuiltinType::OCLNDRange:
5535    case BuiltinType::OCLReserveID:
5536    case BuiltinType::OCLSampler:
5537    case BuiltinType::Dependent:
5538#define BUILTIN_TYPE(KIND, ID)
5539#define PLACEHOLDER_TYPE(KIND, ID) \
5540    case BuiltinType::KIND:
5541#include "clang/AST/BuiltinTypes.def"
5542      llvm_unreachable("invalid builtin type for @encode");
5543    }
5544    llvm_unreachable("invalid BuiltinType::Kind value");
5545}
5546
5547static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
5548  EnumDecl *Enum = ET->getDecl();
5549
5550  // The encoding of an non-fixed enum type is always 'i', regardless of size.
5551  if (!Enum->isFixed())
5552    return 'i';
5553
5554  // The encoding of a fixed enum type matches its fixed underlying type.
5555  const BuiltinType *BT = Enum->getIntegerType()->castAs<BuiltinType>();
5556  return getObjCEncodingForPrimitiveKind(C, BT->getKind());
5557}
5558
5559static void EncodeBitField(const ASTContext *Ctx, std::string& S,
5560                           QualType T, const FieldDecl *FD) {
5561  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
5562  S += 'b';
5563  // The NeXT runtime encodes bit fields as b followed by the number of bits.
5564  // The GNU runtime requires more information; bitfields are encoded as b,
5565  // then the offset (in bits) of the first element, then the type of the
5566  // bitfield, then the size in bits.  For example, in this structure:
5567  //
5568  // struct
5569  // {
5570  //    int integer;
5571  //    int flags:2;
5572  // };
5573  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
5574  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
5575  // information is not especially sensible, but we're stuck with it for
5576  // compatibility with GCC, although providing it breaks anything that
5577  // actually uses runtime introspection and wants to work on both runtimes...
5578  if (Ctx->getLangOpts().ObjCRuntime.isGNUFamily()) {
5579    const RecordDecl *RD = FD->getParent();
5580    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
5581    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
5582    if (const EnumType *ET = T->getAs<EnumType>())
5583      S += ObjCEncodingForEnumType(Ctx, ET);
5584    else {
5585      const BuiltinType *BT = T->castAs<BuiltinType>();
5586      S += getObjCEncodingForPrimitiveKind(Ctx, BT->getKind());
5587    }
5588  }
5589  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
5590}
5591
5592// FIXME: Use SmallString for accumulating string.
5593void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
5594                                            bool ExpandPointedToStructures,
5595                                            bool ExpandStructures,
5596                                            const FieldDecl *FD,
5597                                            bool OutermostType,
5598                                            bool EncodingProperty,
5599                                            bool StructField,
5600                                            bool EncodeBlockParameters,
5601                                            bool EncodeClassNames,
5602                                            bool EncodePointerToObjCTypedef,
5603                                            QualType *NotEncodedT) const {
5604  CanQualType CT = getCanonicalType(T);
5605  switch (CT->getTypeClass()) {
5606  case Type::Builtin:
5607  case Type::Enum:
5608    if (FD && FD->isBitField())
5609      return EncodeBitField(this, S, T, FD);
5610    if (const BuiltinType *BT = dyn_cast<BuiltinType>(CT))
5611      S += getObjCEncodingForPrimitiveKind(this, BT->getKind());
5612    else
5613      S += ObjCEncodingForEnumType(this, cast<EnumType>(CT));
5614    return;
5615
5616  case Type::Complex: {
5617    const ComplexType *CT = T->castAs<ComplexType>();
5618    S += 'j';
5619    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, nullptr);
5620    return;
5621  }
5622
5623  case Type::Atomic: {
5624    const AtomicType *AT = T->castAs<AtomicType>();
5625    S += 'A';
5626    getObjCEncodingForTypeImpl(AT->getValueType(), S, false, false, nullptr);
5627    return;
5628  }
5629
5630  // encoding for pointer or reference types.
5631  case Type::Pointer:
5632  case Type::LValueReference:
5633  case Type::RValueReference: {
5634    QualType PointeeTy;
5635    if (isa<PointerType>(CT)) {
5636      const PointerType *PT = T->castAs<PointerType>();
5637      if (PT->isObjCSelType()) {
5638        S += ':';
5639        return;
5640      }
5641      PointeeTy = PT->getPointeeType();
5642    } else {
5643      PointeeTy = T->castAs<ReferenceType>()->getPointeeType();
5644    }
5645
5646    bool isReadOnly = false;
5647    // For historical/compatibility reasons, the read-only qualifier of the
5648    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
5649    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
5650    // Also, do not emit the 'r' for anything but the outermost type!
5651    if (isa<TypedefType>(T.getTypePtr())) {
5652      if (OutermostType && T.isConstQualified()) {
5653        isReadOnly = true;
5654        S += 'r';
5655      }
5656    } else if (OutermostType) {
5657      QualType P = PointeeTy;
5658      while (P->getAs<PointerType>())
5659        P = P->getAs<PointerType>()->getPointeeType();
5660      if (P.isConstQualified()) {
5661        isReadOnly = true;
5662        S += 'r';
5663      }
5664    }
5665    if (isReadOnly) {
5666      // Another legacy compatibility encoding. Some ObjC qualifier and type
5667      // combinations need to be rearranged.
5668      // Rewrite "in const" from "nr" to "rn"
5669      if (StringRef(S).endswith("nr"))
5670        S.replace(S.end()-2, S.end(), "rn");
5671    }
5672
5673    if (PointeeTy->isCharType()) {
5674      // char pointer types should be encoded as '*' unless it is a
5675      // type that has been typedef'd to 'BOOL'.
5676      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
5677        S += '*';
5678        return;
5679      }
5680    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
5681      // GCC binary compat: Need to convert "struct objc_class *" to "#".
5682      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
5683        S += '#';
5684        return;
5685      }
5686      // GCC binary compat: Need to convert "struct objc_object *" to "@".
5687      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
5688        S += '@';
5689        return;
5690      }
5691      // fall through...
5692    }
5693    S += '^';
5694    getLegacyIntegralTypeEncoding(PointeeTy);
5695
5696    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
5697                               nullptr, false, false, false, false, false, false,
5698                               NotEncodedT);
5699    return;
5700  }
5701
5702  case Type::ConstantArray:
5703  case Type::IncompleteArray:
5704  case Type::VariableArray: {
5705    const ArrayType *AT = cast<ArrayType>(CT);
5706
5707    if (isa<IncompleteArrayType>(AT) && !StructField) {
5708      // Incomplete arrays are encoded as a pointer to the array element.
5709      S += '^';
5710
5711      getObjCEncodingForTypeImpl(AT->getElementType(), S,
5712                                 false, ExpandStructures, FD);
5713    } else {
5714      S += '[';
5715
5716      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
5717        S += llvm::utostr(CAT->getSize().getZExtValue());
5718      else {
5719        //Variable length arrays are encoded as a regular array with 0 elements.
5720        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
5721               "Unknown array type!");
5722        S += '0';
5723      }
5724
5725      getObjCEncodingForTypeImpl(AT->getElementType(), S,
5726                                 false, ExpandStructures, FD,
5727                                 false, false, false, false, false, false,
5728                                 NotEncodedT);
5729      S += ']';
5730    }
5731    return;
5732  }
5733
5734  case Type::FunctionNoProto:
5735  case Type::FunctionProto:
5736    S += '?';
5737    return;
5738
5739  case Type::Record: {
5740    RecordDecl *RDecl = cast<RecordType>(CT)->getDecl();
5741    S += RDecl->isUnion() ? '(' : '{';
5742    // Anonymous structures print as '?'
5743    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
5744      S += II->getName();
5745      if (ClassTemplateSpecializationDecl *Spec
5746          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
5747        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
5748        llvm::raw_string_ostream OS(S);
5749        TemplateSpecializationType::PrintTemplateArgumentList(OS,
5750                                            TemplateArgs.asArray(),
5751                                            (*this).getPrintingPolicy());
5752      }
5753    } else {
5754      S += '?';
5755    }
5756    if (ExpandStructures) {
5757      S += '=';
5758      if (!RDecl->isUnion()) {
5759        getObjCEncodingForStructureImpl(RDecl, S, FD, true, NotEncodedT);
5760      } else {
5761        for (const auto *Field : RDecl->fields()) {
5762          if (FD) {
5763            S += '"';
5764            S += Field->getNameAsString();
5765            S += '"';
5766          }
5767
5768          // Special case bit-fields.
5769          if (Field->isBitField()) {
5770            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
5771                                       Field);
5772          } else {
5773            QualType qt = Field->getType();
5774            getLegacyIntegralTypeEncoding(qt);
5775            getObjCEncodingForTypeImpl(qt, S, false, true,
5776                                       FD, /*OutermostType*/false,
5777                                       /*EncodingProperty*/false,
5778                                       /*StructField*/true,
5779                                       false, false, false, NotEncodedT);
5780          }
5781        }
5782      }
5783    }
5784    S += RDecl->isUnion() ? ')' : '}';
5785    return;
5786  }
5787
5788  case Type::BlockPointer: {
5789    const BlockPointerType *BT = T->castAs<BlockPointerType>();
5790    S += "@?"; // Unlike a pointer-to-function, which is "^?".
5791    if (EncodeBlockParameters) {
5792      const FunctionType *FT = BT->getPointeeType()->castAs<FunctionType>();
5793
5794      S += '<';
5795      // Block return type
5796      getObjCEncodingForTypeImpl(
5797          FT->getReturnType(), S, ExpandPointedToStructures, ExpandStructures,
5798          FD, false /* OutermostType */, EncodingProperty,
5799          false /* StructField */, EncodeBlockParameters, EncodeClassNames, false,
5800                                 NotEncodedT);
5801      // Block self
5802      S += "@?";
5803      // Block parameters
5804      if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT)) {
5805        for (const auto &I : FPT->param_types())
5806          getObjCEncodingForTypeImpl(
5807              I, S, ExpandPointedToStructures, ExpandStructures, FD,
5808              false /* OutermostType */, EncodingProperty,
5809              false /* StructField */, EncodeBlockParameters, EncodeClassNames,
5810                                     false, NotEncodedT);
5811      }
5812      S += '>';
5813    }
5814    return;
5815  }
5816
5817  case Type::ObjCObject: {
5818    // hack to match legacy encoding of *id and *Class
5819    QualType Ty = getObjCObjectPointerType(CT);
5820    if (Ty->isObjCIdType()) {
5821      S += "{objc_object=}";
5822      return;
5823    }
5824    else if (Ty->isObjCClassType()) {
5825      S += "{objc_class=}";
5826      return;
5827    }
5828  }
5829
5830  case Type::ObjCInterface: {
5831    // Ignore protocol qualifiers when mangling at this level.
5832    // @encode(class_name)
5833    ObjCInterfaceDecl *OI = T->castAs<ObjCObjectType>()->getInterface();
5834    S += '{';
5835    S += OI->getObjCRuntimeNameAsString();
5836    S += '=';
5837    SmallVector<const ObjCIvarDecl*, 32> Ivars;
5838    DeepCollectObjCIvars(OI, true, Ivars);
5839    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
5840      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
5841      if (Field->isBitField())
5842        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
5843      else
5844        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD,
5845                                   false, false, false, false, false,
5846                                   EncodePointerToObjCTypedef,
5847                                   NotEncodedT);
5848    }
5849    S += '}';
5850    return;
5851  }
5852
5853  case Type::ObjCObjectPointer: {
5854    const ObjCObjectPointerType *OPT = T->castAs<ObjCObjectPointerType>();
5855    if (OPT->isObjCIdType()) {
5856      S += '@';
5857      return;
5858    }
5859
5860    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
5861      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
5862      // Since this is a binary compatibility issue, need to consult with runtime
5863      // folks. Fortunately, this is a *very* obsure construct.
5864      S += '#';
5865      return;
5866    }
5867
5868    if (OPT->isObjCQualifiedIdType()) {
5869      getObjCEncodingForTypeImpl(getObjCIdType(), S,
5870                                 ExpandPointedToStructures,
5871                                 ExpandStructures, FD);
5872      if (FD || EncodingProperty || EncodeClassNames) {
5873        // Note that we do extended encoding of protocol qualifer list
5874        // Only when doing ivar or property encoding.
5875        S += '"';
5876        for (const auto *I : OPT->quals()) {
5877          S += '<';
5878          S += I->getObjCRuntimeNameAsString();
5879          S += '>';
5880        }
5881        S += '"';
5882      }
5883      return;
5884    }
5885
5886    QualType PointeeTy = OPT->getPointeeType();
5887    if (!EncodingProperty &&
5888        isa<TypedefType>(PointeeTy.getTypePtr()) &&
5889        !EncodePointerToObjCTypedef) {
5890      // Another historical/compatibility reason.
5891      // We encode the underlying type which comes out as
5892      // {...};
5893      S += '^';
5894      if (FD && OPT->getInterfaceDecl()) {
5895        // Prevent recursive encoding of fields in some rare cases.
5896        ObjCInterfaceDecl *OI = OPT->getInterfaceDecl();
5897        SmallVector<const ObjCIvarDecl*, 32> Ivars;
5898        DeepCollectObjCIvars(OI, true, Ivars);
5899        for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
5900          if (cast<FieldDecl>(Ivars[i]) == FD) {
5901            S += '{';
5902            S += OI->getObjCRuntimeNameAsString();
5903            S += '}';
5904            return;
5905          }
5906        }
5907      }
5908      getObjCEncodingForTypeImpl(PointeeTy, S,
5909                                 false, ExpandPointedToStructures,
5910                                 nullptr,
5911                                 false, false, false, false, false,
5912                                 /*EncodePointerToObjCTypedef*/true);
5913      return;
5914    }
5915
5916    S += '@';
5917    if (OPT->getInterfaceDecl() &&
5918        (FD || EncodingProperty || EncodeClassNames)) {
5919      S += '"';
5920      S += OPT->getInterfaceDecl()->getObjCRuntimeNameAsString();
5921      for (const auto *I : OPT->quals()) {
5922        S += '<';
5923        S += I->getObjCRuntimeNameAsString();
5924        S += '>';
5925      }
5926      S += '"';
5927    }
5928    return;
5929  }
5930
5931  // gcc just blithely ignores member pointers.
5932  // FIXME: we shoul do better than that.  'M' is available.
5933  case Type::MemberPointer:
5934  // This matches gcc's encoding, even though technically it is insufficient.
5935  //FIXME. We should do a better job than gcc.
5936  case Type::Vector:
5937  case Type::ExtVector:
5938  // Until we have a coherent encoding of these three types, issue warning.
5939    { if (NotEncodedT)
5940        *NotEncodedT = T;
5941      return;
5942    }
5943
5944  // We could see an undeduced auto type here during error recovery.
5945  // Just ignore it.
5946  case Type::Auto:
5947    return;
5948
5949  case Type::Pipe:
5950#define ABSTRACT_TYPE(KIND, BASE)
5951#define TYPE(KIND, BASE)
5952#define DEPENDENT_TYPE(KIND, BASE) \
5953  case Type::KIND:
5954#define NON_CANONICAL_TYPE(KIND, BASE) \
5955  case Type::KIND:
5956#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(KIND, BASE) \
5957  case Type::KIND:
5958#include "clang/AST/TypeNodes.def"
5959    llvm_unreachable("@encode for dependent type!");
5960  }
5961  llvm_unreachable("bad type kind!");
5962}
5963
5964void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
5965                                                 std::string &S,
5966                                                 const FieldDecl *FD,
5967                                                 bool includeVBases,
5968                                                 QualType *NotEncodedT) const {
5969  assert(RDecl && "Expected non-null RecordDecl");
5970  assert(!RDecl->isUnion() && "Should not be called for unions");
5971  if (!RDecl->getDefinition() || RDecl->getDefinition()->isInvalidDecl())
5972    return;
5973
5974  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
5975  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
5976  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
5977
5978  if (CXXRec) {
5979    for (const auto &BI : CXXRec->bases()) {
5980      if (!BI.isVirtual()) {
5981        CXXRecordDecl *base = BI.getType()->getAsCXXRecordDecl();
5982        if (base->isEmpty())
5983          continue;
5984        uint64_t offs = toBits(layout.getBaseClassOffset(base));
5985        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5986                                  std::make_pair(offs, base));
5987      }
5988    }
5989  }
5990
5991  unsigned i = 0;
5992  for (auto *Field : RDecl->fields()) {
5993    uint64_t offs = layout.getFieldOffset(i);
5994    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5995                              std::make_pair(offs, Field));
5996    ++i;
5997  }
5998
5999  if (CXXRec && includeVBases) {
6000    for (const auto &BI : CXXRec->vbases()) {
6001      CXXRecordDecl *base = BI.getType()->getAsCXXRecordDecl();
6002      if (base->isEmpty())
6003        continue;
6004      uint64_t offs = toBits(layout.getVBaseClassOffset(base));
6005      if (offs >= uint64_t(toBits(layout.getNonVirtualSize())) &&
6006          FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
6007        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
6008                                  std::make_pair(offs, base));
6009    }
6010  }
6011
6012  CharUnits size;
6013  if (CXXRec) {
6014    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
6015  } else {
6016    size = layout.getSize();
6017  }
6018
6019#ifndef NDEBUG
6020  uint64_t CurOffs = 0;
6021#endif
6022  std::multimap<uint64_t, NamedDecl *>::iterator
6023    CurLayObj = FieldOrBaseOffsets.begin();
6024
6025  if (CXXRec && CXXRec->isDynamicClass() &&
6026      (CurLayObj == FieldOrBaseOffsets.end() || CurLayObj->first != 0)) {
6027    if (FD) {
6028      S += "\"_vptr$";
6029      std::string recname = CXXRec->getNameAsString();
6030      if (recname.empty()) recname = "?";
6031      S += recname;
6032      S += '"';
6033    }
6034    S += "^^?";
6035#ifndef NDEBUG
6036    CurOffs += getTypeSize(VoidPtrTy);
6037#endif
6038  }
6039
6040  if (!RDecl->hasFlexibleArrayMember()) {
6041    // Mark the end of the structure.
6042    uint64_t offs = toBits(size);
6043    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
6044                              std::make_pair(offs, nullptr));
6045  }
6046
6047  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
6048#ifndef NDEBUG
6049    assert(CurOffs <= CurLayObj->first);
6050    if (CurOffs < CurLayObj->first) {
6051      uint64_t padding = CurLayObj->first - CurOffs;
6052      // FIXME: There doesn't seem to be a way to indicate in the encoding that
6053      // packing/alignment of members is different that normal, in which case
6054      // the encoding will be out-of-sync with the real layout.
6055      // If the runtime switches to just consider the size of types without
6056      // taking into account alignment, we could make padding explicit in the
6057      // encoding (e.g. using arrays of chars). The encoding strings would be
6058      // longer then though.
6059      CurOffs += padding;
6060    }
6061#endif
6062
6063    NamedDecl *dcl = CurLayObj->second;
6064    if (!dcl)
6065      break; // reached end of structure.
6066
6067    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
6068      // We expand the bases without their virtual bases since those are going
6069      // in the initial structure. Note that this differs from gcc which
6070      // expands virtual bases each time one is encountered in the hierarchy,
6071      // making the encoding type bigger than it really is.
6072      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false,
6073                                      NotEncodedT);
6074      assert(!base->isEmpty());
6075#ifndef NDEBUG
6076      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
6077#endif
6078    } else {
6079      FieldDecl *field = cast<FieldDecl>(dcl);
6080      if (FD) {
6081        S += '"';
6082        S += field->getNameAsString();
6083        S += '"';
6084      }
6085
6086      if (field->isBitField()) {
6087        EncodeBitField(this, S, field->getType(), field);
6088#ifndef NDEBUG
6089        CurOffs += field->getBitWidthValue(*this);
6090#endif
6091      } else {
6092        QualType qt = field->getType();
6093        getLegacyIntegralTypeEncoding(qt);
6094        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
6095                                   /*OutermostType*/false,
6096                                   /*EncodingProperty*/false,
6097                                   /*StructField*/true,
6098                                   false, false, false, NotEncodedT);
6099#ifndef NDEBUG
6100        CurOffs += getTypeSize(field->getType());
6101#endif
6102      }
6103    }
6104  }
6105}
6106
6107void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
6108                                                 std::string& S) const {
6109  if (QT & Decl::OBJC_TQ_In)
6110    S += 'n';
6111  if (QT & Decl::OBJC_TQ_Inout)
6112    S += 'N';
6113  if (QT & Decl::OBJC_TQ_Out)
6114    S += 'o';
6115  if (QT & Decl::OBJC_TQ_Bycopy)
6116    S += 'O';
6117  if (QT & Decl::OBJC_TQ_Byref)
6118    S += 'R';
6119  if (QT & Decl::OBJC_TQ_Oneway)
6120    S += 'V';
6121}
6122
6123TypedefDecl *ASTContext::getObjCIdDecl() const {
6124  if (!ObjCIdDecl) {
6125    QualType T = getObjCObjectType(ObjCBuiltinIdTy, { }, { });
6126    T = getObjCObjectPointerType(T);
6127    ObjCIdDecl = buildImplicitTypedef(T, "id");
6128  }
6129  return ObjCIdDecl;
6130}
6131
6132TypedefDecl *ASTContext::getObjCSelDecl() const {
6133  if (!ObjCSelDecl) {
6134    QualType T = getPointerType(ObjCBuiltinSelTy);
6135    ObjCSelDecl = buildImplicitTypedef(T, "SEL");
6136  }
6137  return ObjCSelDecl;
6138}
6139
6140TypedefDecl *ASTContext::getObjCClassDecl() const {
6141  if (!ObjCClassDecl) {
6142    QualType T = getObjCObjectType(ObjCBuiltinClassTy, { }, { });
6143    T = getObjCObjectPointerType(T);
6144    ObjCClassDecl = buildImplicitTypedef(T, "Class");
6145  }
6146  return ObjCClassDecl;
6147}
6148
6149ObjCInterfaceDecl *ASTContext::getObjCProtocolDecl() const {
6150  if (!ObjCProtocolClassDecl) {
6151    ObjCProtocolClassDecl
6152      = ObjCInterfaceDecl::Create(*this, getTranslationUnitDecl(),
6153                                  SourceLocation(),
6154                                  &Idents.get("Protocol"),
6155                                  /*typeParamList=*/nullptr,
6156                                  /*PrevDecl=*/nullptr,
6157                                  SourceLocation(), true);
6158  }
6159
6160  return ObjCProtocolClassDecl;
6161}
6162
6163//===----------------------------------------------------------------------===//
6164// __builtin_va_list Construction Functions
6165//===----------------------------------------------------------------------===//
6166
6167static TypedefDecl *CreateCharPtrNamedVaListDecl(const ASTContext *Context,
6168                                                 StringRef Name) {
6169  // typedef char* __builtin[_ms]_va_list;
6170  QualType T = Context->getPointerType(Context->CharTy);
6171  return Context->buildImplicitTypedef(T, Name);
6172}
6173
6174static TypedefDecl *CreateMSVaListDecl(const ASTContext *Context) {
6175  return CreateCharPtrNamedVaListDecl(Context, "__builtin_ms_va_list");
6176}
6177
6178static TypedefDecl *CreateCharPtrBuiltinVaListDecl(const ASTContext *Context) {
6179  return CreateCharPtrNamedVaListDecl(Context, "__builtin_va_list");
6180}
6181
6182static TypedefDecl *CreateVoidPtrBuiltinVaListDecl(const ASTContext *Context) {
6183  // typedef void* __builtin_va_list;
6184  QualType T = Context->getPointerType(Context->VoidTy);
6185  return Context->buildImplicitTypedef(T, "__builtin_va_list");
6186}
6187
6188static TypedefDecl *
6189CreateAArch64ABIBuiltinVaListDecl(const ASTContext *Context) {
6190  // struct __va_list
6191  RecordDecl *VaListTagDecl = Context->buildImplicitRecord("__va_list");
6192  if (Context->getLangOpts().CPlusPlus) {
6193    // namespace std { struct __va_list {
6194    NamespaceDecl *NS;
6195    NS = NamespaceDecl::Create(const_cast<ASTContext &>(*Context),
6196                               Context->getTranslationUnitDecl(),
6197                               /*Inline*/ false, SourceLocation(),
6198                               SourceLocation(), &Context->Idents.get("std"),
6199                               /*PrevDecl*/ nullptr);
6200    NS->setImplicit();
6201    VaListTagDecl->setDeclContext(NS);
6202  }
6203
6204  VaListTagDecl->startDefinition();
6205
6206  const size_t NumFields = 5;
6207  QualType FieldTypes[NumFields];
6208  const char *FieldNames[NumFields];
6209
6210  // void *__stack;
6211  FieldTypes[0] = Context->getPointerType(Context->VoidTy);
6212  FieldNames[0] = "__stack";
6213
6214  // void *__gr_top;
6215  FieldTypes[1] = Context->getPointerType(Context->VoidTy);
6216  FieldNames[1] = "__gr_top";
6217
6218  // void *__vr_top;
6219  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
6220  FieldNames[2] = "__vr_top";
6221
6222  // int __gr_offs;
6223  FieldTypes[3] = Context->IntTy;
6224  FieldNames[3] = "__gr_offs";
6225
6226  // int __vr_offs;
6227  FieldTypes[4] = Context->IntTy;
6228  FieldNames[4] = "__vr_offs";
6229
6230  // Create fields
6231  for (unsigned i = 0; i < NumFields; ++i) {
6232    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6233                                         VaListTagDecl,
6234                                         SourceLocation(),
6235                                         SourceLocation(),
6236                                         &Context->Idents.get(FieldNames[i]),
6237                                         FieldTypes[i], /*TInfo=*/nullptr,
6238                                         /*BitWidth=*/nullptr,
6239                                         /*Mutable=*/false,
6240                                         ICIS_NoInit);
6241    Field->setAccess(AS_public);
6242    VaListTagDecl->addDecl(Field);
6243  }
6244  VaListTagDecl->completeDefinition();
6245  Context->VaListTagDecl = VaListTagDecl;
6246  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
6247
6248  // } __builtin_va_list;
6249  return Context->buildImplicitTypedef(VaListTagType, "__builtin_va_list");
6250}
6251
6252static TypedefDecl *CreatePowerABIBuiltinVaListDecl(const ASTContext *Context) {
6253  // typedef struct __va_list_tag {
6254  RecordDecl *VaListTagDecl;
6255
6256  VaListTagDecl = Context->buildImplicitRecord("__va_list_tag");
6257  VaListTagDecl->startDefinition();
6258
6259  const size_t NumFields = 5;
6260  QualType FieldTypes[NumFields];
6261  const char *FieldNames[NumFields];
6262
6263  //   unsigned char gpr;
6264  FieldTypes[0] = Context->UnsignedCharTy;
6265  FieldNames[0] = "gpr";
6266
6267  //   unsigned char fpr;
6268  FieldTypes[1] = Context->UnsignedCharTy;
6269  FieldNames[1] = "fpr";
6270
6271  //   unsigned short reserved;
6272  FieldTypes[2] = Context->UnsignedShortTy;
6273  FieldNames[2] = "reserved";
6274
6275  //   void* overflow_arg_area;
6276  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
6277  FieldNames[3] = "overflow_arg_area";
6278
6279  //   void* reg_save_area;
6280  FieldTypes[4] = Context->getPointerType(Context->VoidTy);
6281  FieldNames[4] = "reg_save_area";
6282
6283  // Create fields
6284  for (unsigned i = 0; i < NumFields; ++i) {
6285    FieldDecl *Field = FieldDecl::Create(*Context, VaListTagDecl,
6286                                         SourceLocation(),
6287                                         SourceLocation(),
6288                                         &Context->Idents.get(FieldNames[i]),
6289                                         FieldTypes[i], /*TInfo=*/nullptr,
6290                                         /*BitWidth=*/nullptr,
6291                                         /*Mutable=*/false,
6292                                         ICIS_NoInit);
6293    Field->setAccess(AS_public);
6294    VaListTagDecl->addDecl(Field);
6295  }
6296  VaListTagDecl->completeDefinition();
6297  Context->VaListTagDecl = VaListTagDecl;
6298  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
6299
6300  // } __va_list_tag;
6301  TypedefDecl *VaListTagTypedefDecl =
6302      Context->buildImplicitTypedef(VaListTagType, "__va_list_tag");
6303
6304  QualType VaListTagTypedefType =
6305    Context->getTypedefType(VaListTagTypedefDecl);
6306
6307  // typedef __va_list_tag __builtin_va_list[1];
6308  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
6309  QualType VaListTagArrayType
6310    = Context->getConstantArrayType(VaListTagTypedefType,
6311                                    Size, ArrayType::Normal, 0);
6312  return Context->buildImplicitTypedef(VaListTagArrayType, "__builtin_va_list");
6313}
6314
6315static TypedefDecl *
6316CreateX86_64ABIBuiltinVaListDecl(const ASTContext *Context) {
6317  // struct __va_list_tag {
6318  RecordDecl *VaListTagDecl;
6319  VaListTagDecl = Context->buildImplicitRecord("__va_list_tag");
6320  VaListTagDecl->startDefinition();
6321
6322  const size_t NumFields = 4;
6323  QualType FieldTypes[NumFields];
6324  const char *FieldNames[NumFields];
6325
6326  //   unsigned gp_offset;
6327  FieldTypes[0] = Context->UnsignedIntTy;
6328  FieldNames[0] = "gp_offset";
6329
6330  //   unsigned fp_offset;
6331  FieldTypes[1] = Context->UnsignedIntTy;
6332  FieldNames[1] = "fp_offset";
6333
6334  //   void* overflow_arg_area;
6335  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
6336  FieldNames[2] = "overflow_arg_area";
6337
6338  //   void* reg_save_area;
6339  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
6340  FieldNames[3] = "reg_save_area";
6341
6342  // Create fields
6343  for (unsigned i = 0; i < NumFields; ++i) {
6344    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6345                                         VaListTagDecl,
6346                                         SourceLocation(),
6347                                         SourceLocation(),
6348                                         &Context->Idents.get(FieldNames[i]),
6349                                         FieldTypes[i], /*TInfo=*/nullptr,
6350                                         /*BitWidth=*/nullptr,
6351                                         /*Mutable=*/false,
6352                                         ICIS_NoInit);
6353    Field->setAccess(AS_public);
6354    VaListTagDecl->addDecl(Field);
6355  }
6356  VaListTagDecl->completeDefinition();
6357  Context->VaListTagDecl = VaListTagDecl;
6358  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
6359
6360  // };
6361
6362  // typedef struct __va_list_tag __builtin_va_list[1];
6363  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
6364  QualType VaListTagArrayType =
6365      Context->getConstantArrayType(VaListTagType, Size, ArrayType::Normal, 0);
6366  return Context->buildImplicitTypedef(VaListTagArrayType, "__builtin_va_list");
6367}
6368
6369static TypedefDecl *CreatePNaClABIBuiltinVaListDecl(const ASTContext *Context) {
6370  // typedef int __builtin_va_list[4];
6371  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 4);
6372  QualType IntArrayType
6373    = Context->getConstantArrayType(Context->IntTy,
6374				    Size, ArrayType::Normal, 0);
6375  return Context->buildImplicitTypedef(IntArrayType, "__builtin_va_list");
6376}
6377
6378static TypedefDecl *
6379CreateAAPCSABIBuiltinVaListDecl(const ASTContext *Context) {
6380  // struct __va_list
6381  RecordDecl *VaListDecl = Context->buildImplicitRecord("__va_list");
6382  if (Context->getLangOpts().CPlusPlus) {
6383    // namespace std { struct __va_list {
6384    NamespaceDecl *NS;
6385    NS = NamespaceDecl::Create(const_cast<ASTContext &>(*Context),
6386                               Context->getTranslationUnitDecl(),
6387                               /*Inline*/false, SourceLocation(),
6388                               SourceLocation(), &Context->Idents.get("std"),
6389                               /*PrevDecl*/ nullptr);
6390    NS->setImplicit();
6391    VaListDecl->setDeclContext(NS);
6392  }
6393
6394  VaListDecl->startDefinition();
6395
6396  // void * __ap;
6397  FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6398                                       VaListDecl,
6399                                       SourceLocation(),
6400                                       SourceLocation(),
6401                                       &Context->Idents.get("__ap"),
6402                                       Context->getPointerType(Context->VoidTy),
6403                                       /*TInfo=*/nullptr,
6404                                       /*BitWidth=*/nullptr,
6405                                       /*Mutable=*/false,
6406                                       ICIS_NoInit);
6407  Field->setAccess(AS_public);
6408  VaListDecl->addDecl(Field);
6409
6410  // };
6411  VaListDecl->completeDefinition();
6412  Context->VaListTagDecl = VaListDecl;
6413
6414  // typedef struct __va_list __builtin_va_list;
6415  QualType T = Context->getRecordType(VaListDecl);
6416  return Context->buildImplicitTypedef(T, "__builtin_va_list");
6417}
6418
6419static TypedefDecl *
6420CreateSystemZBuiltinVaListDecl(const ASTContext *Context) {
6421  // struct __va_list_tag {
6422  RecordDecl *VaListTagDecl;
6423  VaListTagDecl = Context->buildImplicitRecord("__va_list_tag");
6424  VaListTagDecl->startDefinition();
6425
6426  const size_t NumFields = 4;
6427  QualType FieldTypes[NumFields];
6428  const char *FieldNames[NumFields];
6429
6430  //   long __gpr;
6431  FieldTypes[0] = Context->LongTy;
6432  FieldNames[0] = "__gpr";
6433
6434  //   long __fpr;
6435  FieldTypes[1] = Context->LongTy;
6436  FieldNames[1] = "__fpr";
6437
6438  //   void *__overflow_arg_area;
6439  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
6440  FieldNames[2] = "__overflow_arg_area";
6441
6442  //   void *__reg_save_area;
6443  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
6444  FieldNames[3] = "__reg_save_area";
6445
6446  // Create fields
6447  for (unsigned i = 0; i < NumFields; ++i) {
6448    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6449                                         VaListTagDecl,
6450                                         SourceLocation(),
6451                                         SourceLocation(),
6452                                         &Context->Idents.get(FieldNames[i]),
6453                                         FieldTypes[i], /*TInfo=*/nullptr,
6454                                         /*BitWidth=*/nullptr,
6455                                         /*Mutable=*/false,
6456                                         ICIS_NoInit);
6457    Field->setAccess(AS_public);
6458    VaListTagDecl->addDecl(Field);
6459  }
6460  VaListTagDecl->completeDefinition();
6461  Context->VaListTagDecl = VaListTagDecl;
6462  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
6463
6464  // };
6465
6466  // typedef __va_list_tag __builtin_va_list[1];
6467  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
6468  QualType VaListTagArrayType =
6469      Context->getConstantArrayType(VaListTagType, Size, ArrayType::Normal, 0);
6470
6471  return Context->buildImplicitTypedef(VaListTagArrayType, "__builtin_va_list");
6472}
6473
6474static TypedefDecl *CreateVaListDecl(const ASTContext *Context,
6475                                     TargetInfo::BuiltinVaListKind Kind) {
6476  switch (Kind) {
6477  case TargetInfo::CharPtrBuiltinVaList:
6478    return CreateCharPtrBuiltinVaListDecl(Context);
6479  case TargetInfo::VoidPtrBuiltinVaList:
6480    return CreateVoidPtrBuiltinVaListDecl(Context);
6481  case TargetInfo::AArch64ABIBuiltinVaList:
6482    return CreateAArch64ABIBuiltinVaListDecl(Context);
6483  case TargetInfo::PowerABIBuiltinVaList:
6484    return CreatePowerABIBuiltinVaListDecl(Context);
6485  case TargetInfo::X86_64ABIBuiltinVaList:
6486    return CreateX86_64ABIBuiltinVaListDecl(Context);
6487  case TargetInfo::PNaClABIBuiltinVaList:
6488    return CreatePNaClABIBuiltinVaListDecl(Context);
6489  case TargetInfo::AAPCSABIBuiltinVaList:
6490    return CreateAAPCSABIBuiltinVaListDecl(Context);
6491  case TargetInfo::SystemZBuiltinVaList:
6492    return CreateSystemZBuiltinVaListDecl(Context);
6493  }
6494
6495  llvm_unreachable("Unhandled __builtin_va_list type kind");
6496}
6497
6498TypedefDecl *ASTContext::getBuiltinVaListDecl() const {
6499  if (!BuiltinVaListDecl) {
6500    BuiltinVaListDecl = CreateVaListDecl(this, Target->getBuiltinVaListKind());
6501    assert(BuiltinVaListDecl->isImplicit());
6502  }
6503
6504  return BuiltinVaListDecl;
6505}
6506
6507Decl *ASTContext::getVaListTagDecl() const {
6508  // Force the creation of VaListTagDecl by building the __builtin_va_list
6509  // declaration.
6510  if (!VaListTagDecl)
6511    (void)getBuiltinVaListDecl();
6512
6513  return VaListTagDecl;
6514}
6515
6516TypedefDecl *ASTContext::getBuiltinMSVaListDecl() const {
6517  if (!BuiltinMSVaListDecl)
6518    BuiltinMSVaListDecl = CreateMSVaListDecl(this);
6519
6520  return BuiltinMSVaListDecl;
6521}
6522
6523void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
6524  assert(ObjCConstantStringType.isNull() &&
6525         "'NSConstantString' type already set!");
6526
6527  ObjCConstantStringType = getObjCInterfaceType(Decl);
6528}
6529
6530/// \brief Retrieve the template name that corresponds to a non-empty
6531/// lookup.
6532TemplateName
6533ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
6534                                      UnresolvedSetIterator End) const {
6535  unsigned size = End - Begin;
6536  assert(size > 1 && "set is not overloaded!");
6537
6538  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
6539                          size * sizeof(FunctionTemplateDecl*));
6540  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
6541
6542  NamedDecl **Storage = OT->getStorage();
6543  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
6544    NamedDecl *D = *I;
6545    assert(isa<FunctionTemplateDecl>(D) ||
6546           (isa<UsingShadowDecl>(D) &&
6547            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
6548    *Storage++ = D;
6549  }
6550
6551  return TemplateName(OT);
6552}
6553
6554/// \brief Retrieve the template name that represents a qualified
6555/// template name such as \c std::vector.
6556TemplateName
6557ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
6558                                     bool TemplateKeyword,
6559                                     TemplateDecl *Template) const {
6560  assert(NNS && "Missing nested-name-specifier in qualified template name");
6561
6562  // FIXME: Canonicalization?
6563  llvm::FoldingSetNodeID ID;
6564  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
6565
6566  void *InsertPos = nullptr;
6567  QualifiedTemplateName *QTN =
6568    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6569  if (!QTN) {
6570    QTN = new (*this, llvm::alignOf<QualifiedTemplateName>())
6571        QualifiedTemplateName(NNS, TemplateKeyword, Template);
6572    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
6573  }
6574
6575  return TemplateName(QTN);
6576}
6577
6578/// \brief Retrieve the template name that represents a dependent
6579/// template name such as \c MetaFun::template apply.
6580TemplateName
6581ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
6582                                     const IdentifierInfo *Name) const {
6583  assert((!NNS || NNS->isDependent()) &&
6584         "Nested name specifier must be dependent");
6585
6586  llvm::FoldingSetNodeID ID;
6587  DependentTemplateName::Profile(ID, NNS, Name);
6588
6589  void *InsertPos = nullptr;
6590  DependentTemplateName *QTN =
6591    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6592
6593  if (QTN)
6594    return TemplateName(QTN);
6595
6596  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
6597  if (CanonNNS == NNS) {
6598    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6599        DependentTemplateName(NNS, Name);
6600  } else {
6601    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
6602    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6603        DependentTemplateName(NNS, Name, Canon);
6604    DependentTemplateName *CheckQTN =
6605      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6606    assert(!CheckQTN && "Dependent type name canonicalization broken");
6607    (void)CheckQTN;
6608  }
6609
6610  DependentTemplateNames.InsertNode(QTN, InsertPos);
6611  return TemplateName(QTN);
6612}
6613
6614/// \brief Retrieve the template name that represents a dependent
6615/// template name such as \c MetaFun::template operator+.
6616TemplateName
6617ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
6618                                     OverloadedOperatorKind Operator) const {
6619  assert((!NNS || NNS->isDependent()) &&
6620         "Nested name specifier must be dependent");
6621
6622  llvm::FoldingSetNodeID ID;
6623  DependentTemplateName::Profile(ID, NNS, Operator);
6624
6625  void *InsertPos = nullptr;
6626  DependentTemplateName *QTN
6627    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6628
6629  if (QTN)
6630    return TemplateName(QTN);
6631
6632  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
6633  if (CanonNNS == NNS) {
6634    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6635        DependentTemplateName(NNS, Operator);
6636  } else {
6637    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
6638    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6639        DependentTemplateName(NNS, Operator, Canon);
6640
6641    DependentTemplateName *CheckQTN
6642      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6643    assert(!CheckQTN && "Dependent template name canonicalization broken");
6644    (void)CheckQTN;
6645  }
6646
6647  DependentTemplateNames.InsertNode(QTN, InsertPos);
6648  return TemplateName(QTN);
6649}
6650
6651TemplateName
6652ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
6653                                         TemplateName replacement) const {
6654  llvm::FoldingSetNodeID ID;
6655  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
6656
6657  void *insertPos = nullptr;
6658  SubstTemplateTemplateParmStorage *subst
6659    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
6660
6661  if (!subst) {
6662    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
6663    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
6664  }
6665
6666  return TemplateName(subst);
6667}
6668
6669TemplateName
6670ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
6671                                       const TemplateArgument &ArgPack) const {
6672  ASTContext &Self = const_cast<ASTContext &>(*this);
6673  llvm::FoldingSetNodeID ID;
6674  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
6675
6676  void *InsertPos = nullptr;
6677  SubstTemplateTemplateParmPackStorage *Subst
6678    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
6679
6680  if (!Subst) {
6681    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
6682                                                           ArgPack.pack_size(),
6683                                                         ArgPack.pack_begin());
6684    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
6685  }
6686
6687  return TemplateName(Subst);
6688}
6689
6690/// getFromTargetType - Given one of the integer types provided by
6691/// TargetInfo, produce the corresponding type. The unsigned @p Type
6692/// is actually a value of type @c TargetInfo::IntType.
6693CanQualType ASTContext::getFromTargetType(unsigned Type) const {
6694  switch (Type) {
6695  case TargetInfo::NoInt: return CanQualType();
6696  case TargetInfo::SignedChar: return SignedCharTy;
6697  case TargetInfo::UnsignedChar: return UnsignedCharTy;
6698  case TargetInfo::SignedShort: return ShortTy;
6699  case TargetInfo::UnsignedShort: return UnsignedShortTy;
6700  case TargetInfo::SignedInt: return IntTy;
6701  case TargetInfo::UnsignedInt: return UnsignedIntTy;
6702  case TargetInfo::SignedLong: return LongTy;
6703  case TargetInfo::UnsignedLong: return UnsignedLongTy;
6704  case TargetInfo::SignedLongLong: return LongLongTy;
6705  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
6706  }
6707
6708  llvm_unreachable("Unhandled TargetInfo::IntType value");
6709}
6710
6711//===----------------------------------------------------------------------===//
6712//                        Type Predicates.
6713//===----------------------------------------------------------------------===//
6714
6715/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
6716/// garbage collection attribute.
6717///
6718Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
6719  if (getLangOpts().getGC() == LangOptions::NonGC)
6720    return Qualifiers::GCNone;
6721
6722  assert(getLangOpts().ObjC1);
6723  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
6724
6725  // Default behaviour under objective-C's gc is for ObjC pointers
6726  // (or pointers to them) be treated as though they were declared
6727  // as __strong.
6728  if (GCAttrs == Qualifiers::GCNone) {
6729    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
6730      return Qualifiers::Strong;
6731    else if (Ty->isPointerType())
6732      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
6733  } else {
6734    // It's not valid to set GC attributes on anything that isn't a
6735    // pointer.
6736#ifndef NDEBUG
6737    QualType CT = Ty->getCanonicalTypeInternal();
6738    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
6739      CT = AT->getElementType();
6740    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
6741#endif
6742  }
6743  return GCAttrs;
6744}
6745
6746//===----------------------------------------------------------------------===//
6747//                        Type Compatibility Testing
6748//===----------------------------------------------------------------------===//
6749
6750/// areCompatVectorTypes - Return true if the two specified vector types are
6751/// compatible.
6752static bool areCompatVectorTypes(const VectorType *LHS,
6753                                 const VectorType *RHS) {
6754  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
6755  return LHS->getElementType() == RHS->getElementType() &&
6756         LHS->getNumElements() == RHS->getNumElements();
6757}
6758
6759bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
6760                                          QualType SecondVec) {
6761  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
6762  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
6763
6764  if (hasSameUnqualifiedType(FirstVec, SecondVec))
6765    return true;
6766
6767  // Treat Neon vector types and most AltiVec vector types as if they are the
6768  // equivalent GCC vector types.
6769  const VectorType *First = FirstVec->getAs<VectorType>();
6770  const VectorType *Second = SecondVec->getAs<VectorType>();
6771  if (First->getNumElements() == Second->getNumElements() &&
6772      hasSameType(First->getElementType(), Second->getElementType()) &&
6773      First->getVectorKind() != VectorType::AltiVecPixel &&
6774      First->getVectorKind() != VectorType::AltiVecBool &&
6775      Second->getVectorKind() != VectorType::AltiVecPixel &&
6776      Second->getVectorKind() != VectorType::AltiVecBool)
6777    return true;
6778
6779  return false;
6780}
6781
6782//===----------------------------------------------------------------------===//
6783// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
6784//===----------------------------------------------------------------------===//
6785
6786/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
6787/// inheritance hierarchy of 'rProto'.
6788bool
6789ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
6790                                           ObjCProtocolDecl *rProto) const {
6791  if (declaresSameEntity(lProto, rProto))
6792    return true;
6793  for (auto *PI : rProto->protocols())
6794    if (ProtocolCompatibleWithProtocol(lProto, PI))
6795      return true;
6796  return false;
6797}
6798
6799/// ObjCQualifiedClassTypesAreCompatible - compare  Class<pr,...> and
6800/// Class<pr1, ...>.
6801bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
6802                                                      QualType rhs) {
6803  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
6804  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
6805  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
6806
6807  for (auto *lhsProto : lhsQID->quals()) {
6808    bool match = false;
6809    for (auto *rhsProto : rhsOPT->quals()) {
6810      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
6811        match = true;
6812        break;
6813      }
6814    }
6815    if (!match)
6816      return false;
6817  }
6818  return true;
6819}
6820
6821/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
6822/// ObjCQualifiedIDType.
6823bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
6824                                                   bool compare) {
6825  // Allow id<P..> and an 'id' or void* type in all cases.
6826  if (lhs->isVoidPointerType() ||
6827      lhs->isObjCIdType() || lhs->isObjCClassType())
6828    return true;
6829  else if (rhs->isVoidPointerType() ||
6830           rhs->isObjCIdType() || rhs->isObjCClassType())
6831    return true;
6832
6833  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
6834    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
6835
6836    if (!rhsOPT) return false;
6837
6838    if (rhsOPT->qual_empty()) {
6839      // If the RHS is a unqualified interface pointer "NSString*",
6840      // make sure we check the class hierarchy.
6841      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
6842        for (auto *I : lhsQID->quals()) {
6843          // when comparing an id<P> on lhs with a static type on rhs,
6844          // see if static class implements all of id's protocols, directly or
6845          // through its super class and categories.
6846          if (!rhsID->ClassImplementsProtocol(I, true))
6847            return false;
6848        }
6849      }
6850      // If there are no qualifiers and no interface, we have an 'id'.
6851      return true;
6852    }
6853    // Both the right and left sides have qualifiers.
6854    for (auto *lhsProto : lhsQID->quals()) {
6855      bool match = false;
6856
6857      // when comparing an id<P> on lhs with a static type on rhs,
6858      // see if static class implements all of id's protocols, directly or
6859      // through its super class and categories.
6860      for (auto *rhsProto : rhsOPT->quals()) {
6861        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6862            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6863          match = true;
6864          break;
6865        }
6866      }
6867      // If the RHS is a qualified interface pointer "NSString<P>*",
6868      // make sure we check the class hierarchy.
6869      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
6870        for (auto *I : lhsQID->quals()) {
6871          // when comparing an id<P> on lhs with a static type on rhs,
6872          // see if static class implements all of id's protocols, directly or
6873          // through its super class and categories.
6874          if (rhsID->ClassImplementsProtocol(I, true)) {
6875            match = true;
6876            break;
6877          }
6878        }
6879      }
6880      if (!match)
6881        return false;
6882    }
6883
6884    return true;
6885  }
6886
6887  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
6888  assert(rhsQID && "One of the LHS/RHS should be id<x>");
6889
6890  if (const ObjCObjectPointerType *lhsOPT =
6891        lhs->getAsObjCInterfacePointerType()) {
6892    // If both the right and left sides have qualifiers.
6893    for (auto *lhsProto : lhsOPT->quals()) {
6894      bool match = false;
6895
6896      // when comparing an id<P> on rhs with a static type on lhs,
6897      // see if static class implements all of id's protocols, directly or
6898      // through its super class and categories.
6899      // First, lhs protocols in the qualifier list must be found, direct
6900      // or indirect in rhs's qualifier list or it is a mismatch.
6901      for (auto *rhsProto : rhsQID->quals()) {
6902        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6903            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6904          match = true;
6905          break;
6906        }
6907      }
6908      if (!match)
6909        return false;
6910    }
6911
6912    // Static class's protocols, or its super class or category protocols
6913    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
6914    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
6915      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
6916      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
6917      // This is rather dubious but matches gcc's behavior. If lhs has
6918      // no type qualifier and its class has no static protocol(s)
6919      // assume that it is mismatch.
6920      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
6921        return false;
6922      for (auto *lhsProto : LHSInheritedProtocols) {
6923        bool match = false;
6924        for (auto *rhsProto : rhsQID->quals()) {
6925          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6926              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6927            match = true;
6928            break;
6929          }
6930        }
6931        if (!match)
6932          return false;
6933      }
6934    }
6935    return true;
6936  }
6937  return false;
6938}
6939
6940/// canAssignObjCInterfaces - Return true if the two interface types are
6941/// compatible for assignment from RHS to LHS.  This handles validation of any
6942/// protocol qualifiers on the LHS or RHS.
6943///
6944bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
6945                                         const ObjCObjectPointerType *RHSOPT) {
6946  const ObjCObjectType* LHS = LHSOPT->getObjectType();
6947  const ObjCObjectType* RHS = RHSOPT->getObjectType();
6948
6949  // If either type represents the built-in 'id' or 'Class' types, return true.
6950  if (LHS->isObjCUnqualifiedIdOrClass() ||
6951      RHS->isObjCUnqualifiedIdOrClass())
6952    return true;
6953
6954  // Function object that propagates a successful result or handles
6955  // __kindof types.
6956  auto finish = [&](bool succeeded) -> bool {
6957    if (succeeded)
6958      return true;
6959
6960    if (!RHS->isKindOfType())
6961      return false;
6962
6963    // Strip off __kindof and protocol qualifiers, then check whether
6964    // we can assign the other way.
6965    return canAssignObjCInterfaces(RHSOPT->stripObjCKindOfTypeAndQuals(*this),
6966                                   LHSOPT->stripObjCKindOfTypeAndQuals(*this));
6967  };
6968
6969  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId()) {
6970    return finish(ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
6971                                                    QualType(RHSOPT,0),
6972                                                    false));
6973  }
6974
6975  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass()) {
6976    return finish(ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
6977                                                       QualType(RHSOPT,0)));
6978  }
6979
6980  // If we have 2 user-defined types, fall into that path.
6981  if (LHS->getInterface() && RHS->getInterface()) {
6982    return finish(canAssignObjCInterfaces(LHS, RHS));
6983  }
6984
6985  return false;
6986}
6987
6988/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
6989/// for providing type-safety for objective-c pointers used to pass/return
6990/// arguments in block literals. When passed as arguments, passing 'A*' where
6991/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
6992/// not OK. For the return type, the opposite is not OK.
6993bool ASTContext::canAssignObjCInterfacesInBlockPointer(
6994                                         const ObjCObjectPointerType *LHSOPT,
6995                                         const ObjCObjectPointerType *RHSOPT,
6996                                         bool BlockReturnType) {
6997
6998  // Function object that propagates a successful result or handles
6999  // __kindof types.
7000  auto finish = [&](bool succeeded) -> bool {
7001    if (succeeded)
7002      return true;
7003
7004    const ObjCObjectPointerType *Expected = BlockReturnType ? RHSOPT : LHSOPT;
7005    if (!Expected->isKindOfType())
7006      return false;
7007
7008    // Strip off __kindof and protocol qualifiers, then check whether
7009    // we can assign the other way.
7010    return canAssignObjCInterfacesInBlockPointer(
7011             RHSOPT->stripObjCKindOfTypeAndQuals(*this),
7012             LHSOPT->stripObjCKindOfTypeAndQuals(*this),
7013             BlockReturnType);
7014  };
7015
7016  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
7017    return true;
7018
7019  if (LHSOPT->isObjCBuiltinType()) {
7020    return finish(RHSOPT->isObjCBuiltinType() ||
7021                  RHSOPT->isObjCQualifiedIdType());
7022  }
7023
7024  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
7025    return finish(ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
7026                                                    QualType(RHSOPT,0),
7027                                                    false));
7028
7029  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
7030  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
7031  if (LHS && RHS)  { // We have 2 user-defined types.
7032    if (LHS != RHS) {
7033      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
7034        return finish(BlockReturnType);
7035      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
7036        return finish(!BlockReturnType);
7037    }
7038    else
7039      return true;
7040  }
7041  return false;
7042}
7043
7044/// Comparison routine for Objective-C protocols to be used with
7045/// llvm::array_pod_sort.
7046static int compareObjCProtocolsByName(ObjCProtocolDecl * const *lhs,
7047                                      ObjCProtocolDecl * const *rhs) {
7048  return (*lhs)->getName().compare((*rhs)->getName());
7049
7050}
7051
7052/// getIntersectionOfProtocols - This routine finds the intersection of set
7053/// of protocols inherited from two distinct objective-c pointer objects with
7054/// the given common base.
7055/// It is used to build composite qualifier list of the composite type of
7056/// the conditional expression involving two objective-c pointer objects.
7057static
7058void getIntersectionOfProtocols(ASTContext &Context,
7059                                const ObjCInterfaceDecl *CommonBase,
7060                                const ObjCObjectPointerType *LHSOPT,
7061                                const ObjCObjectPointerType *RHSOPT,
7062      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionSet) {
7063
7064  const ObjCObjectType* LHS = LHSOPT->getObjectType();
7065  const ObjCObjectType* RHS = RHSOPT->getObjectType();
7066  assert(LHS->getInterface() && "LHS must have an interface base");
7067  assert(RHS->getInterface() && "RHS must have an interface base");
7068
7069  // Add all of the protocols for the LHS.
7070  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSProtocolSet;
7071
7072  // Start with the protocol qualifiers.
7073  for (auto proto : LHS->quals()) {
7074    Context.CollectInheritedProtocols(proto, LHSProtocolSet);
7075  }
7076
7077  // Also add the protocols associated with the LHS interface.
7078  Context.CollectInheritedProtocols(LHS->getInterface(), LHSProtocolSet);
7079
7080  // Add all of the protocls for the RHS.
7081  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSProtocolSet;
7082
7083  // Start with the protocol qualifiers.
7084  for (auto proto : RHS->quals()) {
7085    Context.CollectInheritedProtocols(proto, RHSProtocolSet);
7086  }
7087
7088  // Also add the protocols associated with the RHS interface.
7089  Context.CollectInheritedProtocols(RHS->getInterface(), RHSProtocolSet);
7090
7091  // Compute the intersection of the collected protocol sets.
7092  for (auto proto : LHSProtocolSet) {
7093    if (RHSProtocolSet.count(proto))
7094      IntersectionSet.push_back(proto);
7095  }
7096
7097  // Compute the set of protocols that is implied by either the common type or
7098  // the protocols within the intersection.
7099  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> ImpliedProtocols;
7100  Context.CollectInheritedProtocols(CommonBase, ImpliedProtocols);
7101
7102  // Remove any implied protocols from the list of inherited protocols.
7103  if (!ImpliedProtocols.empty()) {
7104    IntersectionSet.erase(
7105      std::remove_if(IntersectionSet.begin(),
7106                     IntersectionSet.end(),
7107                     [&](ObjCProtocolDecl *proto) -> bool {
7108                       return ImpliedProtocols.count(proto) > 0;
7109                     }),
7110      IntersectionSet.end());
7111  }
7112
7113  // Sort the remaining protocols by name.
7114  llvm::array_pod_sort(IntersectionSet.begin(), IntersectionSet.end(),
7115                       compareObjCProtocolsByName);
7116}
7117
7118/// Determine whether the first type is a subtype of the second.
7119static bool canAssignObjCObjectTypes(ASTContext &ctx, QualType lhs,
7120                                     QualType rhs) {
7121  // Common case: two object pointers.
7122  const ObjCObjectPointerType *lhsOPT = lhs->getAs<ObjCObjectPointerType>();
7123  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
7124  if (lhsOPT && rhsOPT)
7125    return ctx.canAssignObjCInterfaces(lhsOPT, rhsOPT);
7126
7127  // Two block pointers.
7128  const BlockPointerType *lhsBlock = lhs->getAs<BlockPointerType>();
7129  const BlockPointerType *rhsBlock = rhs->getAs<BlockPointerType>();
7130  if (lhsBlock && rhsBlock)
7131    return ctx.typesAreBlockPointerCompatible(lhs, rhs);
7132
7133  // If either is an unqualified 'id' and the other is a block, it's
7134  // acceptable.
7135  if ((lhsOPT && lhsOPT->isObjCIdType() && rhsBlock) ||
7136      (rhsOPT && rhsOPT->isObjCIdType() && lhsBlock))
7137    return true;
7138
7139  return false;
7140}
7141
7142// Check that the given Objective-C type argument lists are equivalent.
7143static bool sameObjCTypeArgs(ASTContext &ctx,
7144                             const ObjCInterfaceDecl *iface,
7145                             ArrayRef<QualType> lhsArgs,
7146                             ArrayRef<QualType> rhsArgs,
7147                             bool stripKindOf) {
7148  if (lhsArgs.size() != rhsArgs.size())
7149    return false;
7150
7151  ObjCTypeParamList *typeParams = iface->getTypeParamList();
7152  for (unsigned i = 0, n = lhsArgs.size(); i != n; ++i) {
7153    if (ctx.hasSameType(lhsArgs[i], rhsArgs[i]))
7154      continue;
7155
7156    switch (typeParams->begin()[i]->getVariance()) {
7157    case ObjCTypeParamVariance::Invariant:
7158      if (!stripKindOf ||
7159          !ctx.hasSameType(lhsArgs[i].stripObjCKindOfType(ctx),
7160                           rhsArgs[i].stripObjCKindOfType(ctx))) {
7161        return false;
7162      }
7163      break;
7164
7165    case ObjCTypeParamVariance::Covariant:
7166      if (!canAssignObjCObjectTypes(ctx, lhsArgs[i], rhsArgs[i]))
7167        return false;
7168      break;
7169
7170    case ObjCTypeParamVariance::Contravariant:
7171      if (!canAssignObjCObjectTypes(ctx, rhsArgs[i], lhsArgs[i]))
7172        return false;
7173      break;
7174    }
7175  }
7176
7177  return true;
7178}
7179
7180QualType ASTContext::areCommonBaseCompatible(
7181           const ObjCObjectPointerType *Lptr,
7182           const ObjCObjectPointerType *Rptr) {
7183  const ObjCObjectType *LHS = Lptr->getObjectType();
7184  const ObjCObjectType *RHS = Rptr->getObjectType();
7185  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
7186  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
7187
7188  if (!LDecl || !RDecl)
7189    return QualType();
7190
7191  // When either LHS or RHS is a kindof type, we should return a kindof type.
7192  // For example, for common base of kindof(ASub1) and kindof(ASub2), we return
7193  // kindof(A).
7194  bool anyKindOf = LHS->isKindOfType() || RHS->isKindOfType();
7195
7196  // Follow the left-hand side up the class hierarchy until we either hit a
7197  // root or find the RHS. Record the ancestors in case we don't find it.
7198  llvm::SmallDenseMap<const ObjCInterfaceDecl *, const ObjCObjectType *, 4>
7199    LHSAncestors;
7200  while (true) {
7201    // Record this ancestor. We'll need this if the common type isn't in the
7202    // path from the LHS to the root.
7203    LHSAncestors[LHS->getInterface()->getCanonicalDecl()] = LHS;
7204
7205    if (declaresSameEntity(LHS->getInterface(), RDecl)) {
7206      // Get the type arguments.
7207      ArrayRef<QualType> LHSTypeArgs = LHS->getTypeArgsAsWritten();
7208      bool anyChanges = false;
7209      if (LHS->isSpecialized() && RHS->isSpecialized()) {
7210        // Both have type arguments, compare them.
7211        if (!sameObjCTypeArgs(*this, LHS->getInterface(),
7212                              LHS->getTypeArgs(), RHS->getTypeArgs(),
7213                              /*stripKindOf=*/true))
7214          return QualType();
7215      } else if (LHS->isSpecialized() != RHS->isSpecialized()) {
7216        // If only one has type arguments, the result will not have type
7217        // arguments.
7218        LHSTypeArgs = { };
7219        anyChanges = true;
7220      }
7221
7222      // Compute the intersection of protocols.
7223      SmallVector<ObjCProtocolDecl *, 8> Protocols;
7224      getIntersectionOfProtocols(*this, LHS->getInterface(), Lptr, Rptr,
7225                                 Protocols);
7226      if (!Protocols.empty())
7227        anyChanges = true;
7228
7229      // If anything in the LHS will have changed, build a new result type.
7230      // If we need to return a kindof type but LHS is not a kindof type, we
7231      // build a new result type.
7232      if (anyChanges || LHS->isKindOfType() != anyKindOf) {
7233        QualType Result = getObjCInterfaceType(LHS->getInterface());
7234        Result = getObjCObjectType(Result, LHSTypeArgs, Protocols,
7235                                   anyKindOf || LHS->isKindOfType());
7236        return getObjCObjectPointerType(Result);
7237      }
7238
7239      return getObjCObjectPointerType(QualType(LHS, 0));
7240    }
7241
7242    // Find the superclass.
7243    QualType LHSSuperType = LHS->getSuperClassType();
7244    if (LHSSuperType.isNull())
7245      break;
7246
7247    LHS = LHSSuperType->castAs<ObjCObjectType>();
7248  }
7249
7250  // We didn't find anything by following the LHS to its root; now check
7251  // the RHS against the cached set of ancestors.
7252  while (true) {
7253    auto KnownLHS = LHSAncestors.find(RHS->getInterface()->getCanonicalDecl());
7254    if (KnownLHS != LHSAncestors.end()) {
7255      LHS = KnownLHS->second;
7256
7257      // Get the type arguments.
7258      ArrayRef<QualType> RHSTypeArgs = RHS->getTypeArgsAsWritten();
7259      bool anyChanges = false;
7260      if (LHS->isSpecialized() && RHS->isSpecialized()) {
7261        // Both have type arguments, compare them.
7262        if (!sameObjCTypeArgs(*this, LHS->getInterface(),
7263                              LHS->getTypeArgs(), RHS->getTypeArgs(),
7264                              /*stripKindOf=*/true))
7265          return QualType();
7266      } else if (LHS->isSpecialized() != RHS->isSpecialized()) {
7267        // If only one has type arguments, the result will not have type
7268        // arguments.
7269        RHSTypeArgs = { };
7270        anyChanges = true;
7271      }
7272
7273      // Compute the intersection of protocols.
7274      SmallVector<ObjCProtocolDecl *, 8> Protocols;
7275      getIntersectionOfProtocols(*this, RHS->getInterface(), Lptr, Rptr,
7276                                 Protocols);
7277      if (!Protocols.empty())
7278        anyChanges = true;
7279
7280      // If we need to return a kindof type but RHS is not a kindof type, we
7281      // build a new result type.
7282      if (anyChanges || RHS->isKindOfType() != anyKindOf) {
7283        QualType Result = getObjCInterfaceType(RHS->getInterface());
7284        Result = getObjCObjectType(Result, RHSTypeArgs, Protocols,
7285                                   anyKindOf || RHS->isKindOfType());
7286        return getObjCObjectPointerType(Result);
7287      }
7288
7289      return getObjCObjectPointerType(QualType(RHS, 0));
7290    }
7291
7292    // Find the superclass of the RHS.
7293    QualType RHSSuperType = RHS->getSuperClassType();
7294    if (RHSSuperType.isNull())
7295      break;
7296
7297    RHS = RHSSuperType->castAs<ObjCObjectType>();
7298  }
7299
7300  return QualType();
7301}
7302
7303bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
7304                                         const ObjCObjectType *RHS) {
7305  assert(LHS->getInterface() && "LHS is not an interface type");
7306  assert(RHS->getInterface() && "RHS is not an interface type");
7307
7308  // Verify that the base decls are compatible: the RHS must be a subclass of
7309  // the LHS.
7310  ObjCInterfaceDecl *LHSInterface = LHS->getInterface();
7311  bool IsSuperClass = LHSInterface->isSuperClassOf(RHS->getInterface());
7312  if (!IsSuperClass)
7313    return false;
7314
7315  // If the LHS has protocol qualifiers, determine whether all of them are
7316  // satisfied by the RHS (i.e., the RHS has a superset of the protocols in the
7317  // LHS).
7318  if (LHS->getNumProtocols() > 0) {
7319    // OK if conversion of LHS to SuperClass results in narrowing of types
7320    // ; i.e., SuperClass may implement at least one of the protocols
7321    // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
7322    // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
7323    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
7324    CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
7325    // Also, if RHS has explicit quelifiers, include them for comparing with LHS's
7326    // qualifiers.
7327    for (auto *RHSPI : RHS->quals())
7328      CollectInheritedProtocols(RHSPI, SuperClassInheritedProtocols);
7329    // If there is no protocols associated with RHS, it is not a match.
7330    if (SuperClassInheritedProtocols.empty())
7331      return false;
7332
7333    for (const auto *LHSProto : LHS->quals()) {
7334      bool SuperImplementsProtocol = false;
7335      for (auto *SuperClassProto : SuperClassInheritedProtocols)
7336        if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
7337          SuperImplementsProtocol = true;
7338          break;
7339        }
7340      if (!SuperImplementsProtocol)
7341        return false;
7342    }
7343  }
7344
7345  // If the LHS is specialized, we may need to check type arguments.
7346  if (LHS->isSpecialized()) {
7347    // Follow the superclass chain until we've matched the LHS class in the
7348    // hierarchy. This substitutes type arguments through.
7349    const ObjCObjectType *RHSSuper = RHS;
7350    while (!declaresSameEntity(RHSSuper->getInterface(), LHSInterface))
7351      RHSSuper = RHSSuper->getSuperClassType()->castAs<ObjCObjectType>();
7352
7353    // If the RHS is specializd, compare type arguments.
7354    if (RHSSuper->isSpecialized() &&
7355        !sameObjCTypeArgs(*this, LHS->getInterface(),
7356                          LHS->getTypeArgs(), RHSSuper->getTypeArgs(),
7357                          /*stripKindOf=*/true)) {
7358      return false;
7359    }
7360  }
7361
7362  return true;
7363}
7364
7365bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
7366  // get the "pointed to" types
7367  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
7368  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
7369
7370  if (!LHSOPT || !RHSOPT)
7371    return false;
7372
7373  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
7374         canAssignObjCInterfaces(RHSOPT, LHSOPT);
7375}
7376
7377bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
7378  return canAssignObjCInterfaces(
7379                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
7380                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
7381}
7382
7383/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
7384/// both shall have the identically qualified version of a compatible type.
7385/// C99 6.2.7p1: Two types have compatible types if their types are the
7386/// same. See 6.7.[2,3,5] for additional rules.
7387bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
7388                                    bool CompareUnqualified) {
7389  if (getLangOpts().CPlusPlus)
7390    return hasSameType(LHS, RHS);
7391
7392  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
7393}
7394
7395bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
7396  return typesAreCompatible(LHS, RHS);
7397}
7398
7399bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
7400  return !mergeTypes(LHS, RHS, true).isNull();
7401}
7402
7403/// mergeTransparentUnionType - if T is a transparent union type and a member
7404/// of T is compatible with SubType, return the merged type, else return
7405/// QualType()
7406QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
7407                                               bool OfBlockPointer,
7408                                               bool Unqualified) {
7409  if (const RecordType *UT = T->getAsUnionType()) {
7410    RecordDecl *UD = UT->getDecl();
7411    if (UD->hasAttr<TransparentUnionAttr>()) {
7412      for (const auto *I : UD->fields()) {
7413        QualType ET = I->getType().getUnqualifiedType();
7414        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
7415        if (!MT.isNull())
7416          return MT;
7417      }
7418    }
7419  }
7420
7421  return QualType();
7422}
7423
7424/// mergeFunctionParameterTypes - merge two types which appear as function
7425/// parameter types
7426QualType ASTContext::mergeFunctionParameterTypes(QualType lhs, QualType rhs,
7427                                                 bool OfBlockPointer,
7428                                                 bool Unqualified) {
7429  // GNU extension: two types are compatible if they appear as a function
7430  // argument, one of the types is a transparent union type and the other
7431  // type is compatible with a union member
7432  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
7433                                              Unqualified);
7434  if (!lmerge.isNull())
7435    return lmerge;
7436
7437  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
7438                                              Unqualified);
7439  if (!rmerge.isNull())
7440    return rmerge;
7441
7442  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
7443}
7444
7445QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
7446                                        bool OfBlockPointer,
7447                                        bool Unqualified) {
7448  const FunctionType *lbase = lhs->getAs<FunctionType>();
7449  const FunctionType *rbase = rhs->getAs<FunctionType>();
7450  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
7451  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
7452  bool allLTypes = true;
7453  bool allRTypes = true;
7454
7455  // Check return type
7456  QualType retType;
7457  if (OfBlockPointer) {
7458    QualType RHS = rbase->getReturnType();
7459    QualType LHS = lbase->getReturnType();
7460    bool UnqualifiedResult = Unqualified;
7461    if (!UnqualifiedResult)
7462      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
7463    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
7464  }
7465  else
7466    retType = mergeTypes(lbase->getReturnType(), rbase->getReturnType(), false,
7467                         Unqualified);
7468  if (retType.isNull()) return QualType();
7469
7470  if (Unqualified)
7471    retType = retType.getUnqualifiedType();
7472
7473  CanQualType LRetType = getCanonicalType(lbase->getReturnType());
7474  CanQualType RRetType = getCanonicalType(rbase->getReturnType());
7475  if (Unqualified) {
7476    LRetType = LRetType.getUnqualifiedType();
7477    RRetType = RRetType.getUnqualifiedType();
7478  }
7479
7480  if (getCanonicalType(retType) != LRetType)
7481    allLTypes = false;
7482  if (getCanonicalType(retType) != RRetType)
7483    allRTypes = false;
7484
7485  // FIXME: double check this
7486  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
7487  //                           rbase->getRegParmAttr() != 0 &&
7488  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
7489  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
7490  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
7491
7492  // Compatible functions must have compatible calling conventions
7493  if (lbaseInfo.getCC() != rbaseInfo.getCC())
7494    return QualType();
7495
7496  // Regparm is part of the calling convention.
7497  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
7498    return QualType();
7499  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
7500    return QualType();
7501
7502  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
7503    return QualType();
7504
7505  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
7506  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
7507
7508  if (lbaseInfo.getNoReturn() != NoReturn)
7509    allLTypes = false;
7510  if (rbaseInfo.getNoReturn() != NoReturn)
7511    allRTypes = false;
7512
7513  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
7514
7515  if (lproto && rproto) { // two C99 style function prototypes
7516    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
7517           "C++ shouldn't be here");
7518    // Compatible functions must have the same number of parameters
7519    if (lproto->getNumParams() != rproto->getNumParams())
7520      return QualType();
7521
7522    // Variadic and non-variadic functions aren't compatible
7523    if (lproto->isVariadic() != rproto->isVariadic())
7524      return QualType();
7525
7526    if (lproto->getTypeQuals() != rproto->getTypeQuals())
7527      return QualType();
7528
7529    if (!doFunctionTypesMatchOnExtParameterInfos(rproto, lproto))
7530      return QualType();
7531
7532    // Check parameter type compatibility
7533    SmallVector<QualType, 10> types;
7534    for (unsigned i = 0, n = lproto->getNumParams(); i < n; i++) {
7535      QualType lParamType = lproto->getParamType(i).getUnqualifiedType();
7536      QualType rParamType = rproto->getParamType(i).getUnqualifiedType();
7537      QualType paramType = mergeFunctionParameterTypes(
7538          lParamType, rParamType, OfBlockPointer, Unqualified);
7539      if (paramType.isNull())
7540        return QualType();
7541
7542      if (Unqualified)
7543        paramType = paramType.getUnqualifiedType();
7544
7545      types.push_back(paramType);
7546      if (Unqualified) {
7547        lParamType = lParamType.getUnqualifiedType();
7548        rParamType = rParamType.getUnqualifiedType();
7549      }
7550
7551      if (getCanonicalType(paramType) != getCanonicalType(lParamType))
7552        allLTypes = false;
7553      if (getCanonicalType(paramType) != getCanonicalType(rParamType))
7554        allRTypes = false;
7555    }
7556
7557    if (allLTypes) return lhs;
7558    if (allRTypes) return rhs;
7559
7560    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
7561    EPI.ExtInfo = einfo;
7562    return getFunctionType(retType, types, EPI);
7563  }
7564
7565  if (lproto) allRTypes = false;
7566  if (rproto) allLTypes = false;
7567
7568  const FunctionProtoType *proto = lproto ? lproto : rproto;
7569  if (proto) {
7570    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
7571    if (proto->isVariadic()) return QualType();
7572    // Check that the types are compatible with the types that
7573    // would result from default argument promotions (C99 6.7.5.3p15).
7574    // The only types actually affected are promotable integer
7575    // types and floats, which would be passed as a different
7576    // type depending on whether the prototype is visible.
7577    for (unsigned i = 0, n = proto->getNumParams(); i < n; ++i) {
7578      QualType paramTy = proto->getParamType(i);
7579
7580      // Look at the converted type of enum types, since that is the type used
7581      // to pass enum values.
7582      if (const EnumType *Enum = paramTy->getAs<EnumType>()) {
7583        paramTy = Enum->getDecl()->getIntegerType();
7584        if (paramTy.isNull())
7585          return QualType();
7586      }
7587
7588      if (paramTy->isPromotableIntegerType() ||
7589          getCanonicalType(paramTy).getUnqualifiedType() == FloatTy)
7590        return QualType();
7591    }
7592
7593    if (allLTypes) return lhs;
7594    if (allRTypes) return rhs;
7595
7596    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
7597    EPI.ExtInfo = einfo;
7598    return getFunctionType(retType, proto->getParamTypes(), EPI);
7599  }
7600
7601  if (allLTypes) return lhs;
7602  if (allRTypes) return rhs;
7603  return getFunctionNoProtoType(retType, einfo);
7604}
7605
7606/// Given that we have an enum type and a non-enum type, try to merge them.
7607static QualType mergeEnumWithInteger(ASTContext &Context, const EnumType *ET,
7608                                     QualType other, bool isBlockReturnType) {
7609  // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
7610  // a signed integer type, or an unsigned integer type.
7611  // Compatibility is based on the underlying type, not the promotion
7612  // type.
7613  QualType underlyingType = ET->getDecl()->getIntegerType();
7614  if (underlyingType.isNull()) return QualType();
7615  if (Context.hasSameType(underlyingType, other))
7616    return other;
7617
7618  // In block return types, we're more permissive and accept any
7619  // integral type of the same size.
7620  if (isBlockReturnType && other->isIntegerType() &&
7621      Context.getTypeSize(underlyingType) == Context.getTypeSize(other))
7622    return other;
7623
7624  return QualType();
7625}
7626
7627QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
7628                                bool OfBlockPointer,
7629                                bool Unqualified, bool BlockReturnType) {
7630  // C++ [expr]: If an expression initially has the type "reference to T", the
7631  // type is adjusted to "T" prior to any further analysis, the expression
7632  // designates the object or function denoted by the reference, and the
7633  // expression is an lvalue unless the reference is an rvalue reference and
7634  // the expression is a function call (possibly inside parentheses).
7635  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
7636  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
7637
7638  if (Unqualified) {
7639    LHS = LHS.getUnqualifiedType();
7640    RHS = RHS.getUnqualifiedType();
7641  }
7642
7643  QualType LHSCan = getCanonicalType(LHS),
7644           RHSCan = getCanonicalType(RHS);
7645
7646  // If two types are identical, they are compatible.
7647  if (LHSCan == RHSCan)
7648    return LHS;
7649
7650  // If the qualifiers are different, the types aren't compatible... mostly.
7651  Qualifiers LQuals = LHSCan.getLocalQualifiers();
7652  Qualifiers RQuals = RHSCan.getLocalQualifiers();
7653  if (LQuals != RQuals) {
7654    if (getLangOpts().OpenCL) {
7655      if (LHSCan.getUnqualifiedType() != RHSCan.getUnqualifiedType() ||
7656          LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers())
7657        return QualType();
7658      if (LQuals.isAddressSpaceSupersetOf(RQuals))
7659        return LHS;
7660      if (RQuals.isAddressSpaceSupersetOf(LQuals))
7661        return RHS;
7662    }
7663    // If any of these qualifiers are different, we have a type
7664    // mismatch.
7665    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
7666        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
7667        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
7668      return QualType();
7669
7670    // Exactly one GC qualifier difference is allowed: __strong is
7671    // okay if the other type has no GC qualifier but is an Objective
7672    // C object pointer (i.e. implicitly strong by default).  We fix
7673    // this by pretending that the unqualified type was actually
7674    // qualified __strong.
7675    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
7676    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
7677    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
7678
7679    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
7680      return QualType();
7681
7682    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
7683      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
7684    }
7685    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
7686      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
7687    }
7688    return QualType();
7689  }
7690
7691  // Okay, qualifiers are equal.
7692
7693  Type::TypeClass LHSClass = LHSCan->getTypeClass();
7694  Type::TypeClass RHSClass = RHSCan->getTypeClass();
7695
7696  // We want to consider the two function types to be the same for these
7697  // comparisons, just force one to the other.
7698  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
7699  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
7700
7701  // Same as above for arrays
7702  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
7703    LHSClass = Type::ConstantArray;
7704  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
7705    RHSClass = Type::ConstantArray;
7706
7707  // ObjCInterfaces are just specialized ObjCObjects.
7708  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
7709  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
7710
7711  // Canonicalize ExtVector -> Vector.
7712  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
7713  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
7714
7715  // If the canonical type classes don't match.
7716  if (LHSClass != RHSClass) {
7717    // Note that we only have special rules for turning block enum
7718    // returns into block int returns, not vice-versa.
7719    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
7720      return mergeEnumWithInteger(*this, ETy, RHS, false);
7721    }
7722    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
7723      return mergeEnumWithInteger(*this, ETy, LHS, BlockReturnType);
7724    }
7725    // allow block pointer type to match an 'id' type.
7726    if (OfBlockPointer && !BlockReturnType) {
7727       if (LHS->isObjCIdType() && RHS->isBlockPointerType())
7728         return LHS;
7729      if (RHS->isObjCIdType() && LHS->isBlockPointerType())
7730        return RHS;
7731    }
7732
7733    return QualType();
7734  }
7735
7736  // The canonical type classes match.
7737  switch (LHSClass) {
7738#define TYPE(Class, Base)
7739#define ABSTRACT_TYPE(Class, Base)
7740#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
7741#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
7742#define DEPENDENT_TYPE(Class, Base) case Type::Class:
7743#include "clang/AST/TypeNodes.def"
7744    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
7745
7746  case Type::Auto:
7747  case Type::LValueReference:
7748  case Type::RValueReference:
7749  case Type::MemberPointer:
7750    llvm_unreachable("C++ should never be in mergeTypes");
7751
7752  case Type::ObjCInterface:
7753  case Type::IncompleteArray:
7754  case Type::VariableArray:
7755  case Type::FunctionProto:
7756  case Type::ExtVector:
7757    llvm_unreachable("Types are eliminated above");
7758
7759  case Type::Pointer:
7760  {
7761    // Merge two pointer types, while trying to preserve typedef info
7762    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
7763    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
7764    if (Unqualified) {
7765      LHSPointee = LHSPointee.getUnqualifiedType();
7766      RHSPointee = RHSPointee.getUnqualifiedType();
7767    }
7768    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
7769                                     Unqualified);
7770    if (ResultType.isNull()) return QualType();
7771    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
7772      return LHS;
7773    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
7774      return RHS;
7775    return getPointerType(ResultType);
7776  }
7777  case Type::BlockPointer:
7778  {
7779    // Merge two block pointer types, while trying to preserve typedef info
7780    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
7781    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
7782    if (Unqualified) {
7783      LHSPointee = LHSPointee.getUnqualifiedType();
7784      RHSPointee = RHSPointee.getUnqualifiedType();
7785    }
7786    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
7787                                     Unqualified);
7788    if (ResultType.isNull()) return QualType();
7789    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
7790      return LHS;
7791    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
7792      return RHS;
7793    return getBlockPointerType(ResultType);
7794  }
7795  case Type::Atomic:
7796  {
7797    // Merge two pointer types, while trying to preserve typedef info
7798    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
7799    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
7800    if (Unqualified) {
7801      LHSValue = LHSValue.getUnqualifiedType();
7802      RHSValue = RHSValue.getUnqualifiedType();
7803    }
7804    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
7805                                     Unqualified);
7806    if (ResultType.isNull()) return QualType();
7807    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
7808      return LHS;
7809    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
7810      return RHS;
7811    return getAtomicType(ResultType);
7812  }
7813  case Type::ConstantArray:
7814  {
7815    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
7816    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
7817    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
7818      return QualType();
7819
7820    QualType LHSElem = getAsArrayType(LHS)->getElementType();
7821    QualType RHSElem = getAsArrayType(RHS)->getElementType();
7822    if (Unqualified) {
7823      LHSElem = LHSElem.getUnqualifiedType();
7824      RHSElem = RHSElem.getUnqualifiedType();
7825    }
7826
7827    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
7828    if (ResultType.isNull()) return QualType();
7829    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
7830      return LHS;
7831    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
7832      return RHS;
7833    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
7834                                          ArrayType::ArraySizeModifier(), 0);
7835    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
7836                                          ArrayType::ArraySizeModifier(), 0);
7837    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
7838    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
7839    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
7840      return LHS;
7841    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
7842      return RHS;
7843    if (LVAT) {
7844      // FIXME: This isn't correct! But tricky to implement because
7845      // the array's size has to be the size of LHS, but the type
7846      // has to be different.
7847      return LHS;
7848    }
7849    if (RVAT) {
7850      // FIXME: This isn't correct! But tricky to implement because
7851      // the array's size has to be the size of RHS, but the type
7852      // has to be different.
7853      return RHS;
7854    }
7855    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
7856    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
7857    return getIncompleteArrayType(ResultType,
7858                                  ArrayType::ArraySizeModifier(), 0);
7859  }
7860  case Type::FunctionNoProto:
7861    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
7862  case Type::Record:
7863  case Type::Enum:
7864    return QualType();
7865  case Type::Builtin:
7866    // Only exactly equal builtin types are compatible, which is tested above.
7867    return QualType();
7868  case Type::Complex:
7869    // Distinct complex types are incompatible.
7870    return QualType();
7871  case Type::Vector:
7872    // FIXME: The merged type should be an ExtVector!
7873    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
7874                             RHSCan->getAs<VectorType>()))
7875      return LHS;
7876    return QualType();
7877  case Type::ObjCObject: {
7878    // Check if the types are assignment compatible.
7879    // FIXME: This should be type compatibility, e.g. whether
7880    // "LHS x; RHS x;" at global scope is legal.
7881    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
7882    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
7883    if (canAssignObjCInterfaces(LHSIface, RHSIface))
7884      return LHS;
7885
7886    return QualType();
7887  }
7888  case Type::ObjCObjectPointer: {
7889    if (OfBlockPointer) {
7890      if (canAssignObjCInterfacesInBlockPointer(
7891                                          LHS->getAs<ObjCObjectPointerType>(),
7892                                          RHS->getAs<ObjCObjectPointerType>(),
7893                                          BlockReturnType))
7894        return LHS;
7895      return QualType();
7896    }
7897    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
7898                                RHS->getAs<ObjCObjectPointerType>()))
7899      return LHS;
7900
7901    return QualType();
7902  }
7903  case Type::Pipe:
7904  {
7905    // Merge two pointer types, while trying to preserve typedef info
7906    QualType LHSValue = LHS->getAs<PipeType>()->getElementType();
7907    QualType RHSValue = RHS->getAs<PipeType>()->getElementType();
7908    if (Unqualified) {
7909      LHSValue = LHSValue.getUnqualifiedType();
7910      RHSValue = RHSValue.getUnqualifiedType();
7911    }
7912    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
7913                                     Unqualified);
7914    if (ResultType.isNull()) return QualType();
7915    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
7916      return LHS;
7917    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
7918      return RHS;
7919    return getPipeType(ResultType);
7920  }
7921  }
7922
7923  llvm_unreachable("Invalid Type::Class!");
7924}
7925
7926bool ASTContext::doFunctionTypesMatchOnExtParameterInfos(
7927                   const FunctionProtoType *firstFnType,
7928                   const FunctionProtoType *secondFnType) {
7929  // Fast path: if the first type doesn't have ext parameter infos,
7930  // we match if and only if they second type also doesn't have them.
7931  if (!firstFnType->hasExtParameterInfos())
7932    return !secondFnType->hasExtParameterInfos();
7933
7934  // Otherwise, we can only match if the second type has them.
7935  if (!secondFnType->hasExtParameterInfos())
7936    return false;
7937
7938  auto firstEPI = firstFnType->getExtParameterInfos();
7939  auto secondEPI = secondFnType->getExtParameterInfos();
7940  assert(firstEPI.size() == secondEPI.size());
7941
7942  for (size_t i = 0, n = firstEPI.size(); i != n; ++i) {
7943    if (firstEPI[i] != secondEPI[i])
7944      return false;
7945  }
7946  return true;
7947}
7948
7949void ASTContext::ResetObjCLayout(const ObjCContainerDecl *CD) {
7950  ObjCLayouts[CD] = nullptr;
7951}
7952
7953/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
7954/// 'RHS' attributes and returns the merged version; including for function
7955/// return types.
7956QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
7957  QualType LHSCan = getCanonicalType(LHS),
7958  RHSCan = getCanonicalType(RHS);
7959  // If two types are identical, they are compatible.
7960  if (LHSCan == RHSCan)
7961    return LHS;
7962  if (RHSCan->isFunctionType()) {
7963    if (!LHSCan->isFunctionType())
7964      return QualType();
7965    QualType OldReturnType =
7966        cast<FunctionType>(RHSCan.getTypePtr())->getReturnType();
7967    QualType NewReturnType =
7968        cast<FunctionType>(LHSCan.getTypePtr())->getReturnType();
7969    QualType ResReturnType =
7970      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
7971    if (ResReturnType.isNull())
7972      return QualType();
7973    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
7974      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
7975      // In either case, use OldReturnType to build the new function type.
7976      const FunctionType *F = LHS->getAs<FunctionType>();
7977      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
7978        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
7979        EPI.ExtInfo = getFunctionExtInfo(LHS);
7980        QualType ResultType =
7981            getFunctionType(OldReturnType, FPT->getParamTypes(), EPI);
7982        return ResultType;
7983      }
7984    }
7985    return QualType();
7986  }
7987
7988  // If the qualifiers are different, the types can still be merged.
7989  Qualifiers LQuals = LHSCan.getLocalQualifiers();
7990  Qualifiers RQuals = RHSCan.getLocalQualifiers();
7991  if (LQuals != RQuals) {
7992    // If any of these qualifiers are different, we have a type mismatch.
7993    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
7994        LQuals.getAddressSpace() != RQuals.getAddressSpace())
7995      return QualType();
7996
7997    // Exactly one GC qualifier difference is allowed: __strong is
7998    // okay if the other type has no GC qualifier but is an Objective
7999    // C object pointer (i.e. implicitly strong by default).  We fix
8000    // this by pretending that the unqualified type was actually
8001    // qualified __strong.
8002    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
8003    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
8004    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
8005
8006    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
8007      return QualType();
8008
8009    if (GC_L == Qualifiers::Strong)
8010      return LHS;
8011    if (GC_R == Qualifiers::Strong)
8012      return RHS;
8013    return QualType();
8014  }
8015
8016  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
8017    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
8018    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
8019    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
8020    if (ResQT == LHSBaseQT)
8021      return LHS;
8022    if (ResQT == RHSBaseQT)
8023      return RHS;
8024  }
8025  return QualType();
8026}
8027
8028//===----------------------------------------------------------------------===//
8029//                         Integer Predicates
8030//===----------------------------------------------------------------------===//
8031
8032unsigned ASTContext::getIntWidth(QualType T) const {
8033  if (const EnumType *ET = T->getAs<EnumType>())
8034    T = ET->getDecl()->getIntegerType();
8035  if (T->isBooleanType())
8036    return 1;
8037  // For builtin types, just use the standard type sizing method
8038  return (unsigned)getTypeSize(T);
8039}
8040
8041QualType ASTContext::getCorrespondingUnsignedType(QualType T) const {
8042  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
8043
8044  // Turn <4 x signed int> -> <4 x unsigned int>
8045  if (const VectorType *VTy = T->getAs<VectorType>())
8046    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
8047                         VTy->getNumElements(), VTy->getVectorKind());
8048
8049  // For enums, we return the unsigned version of the base type.
8050  if (const EnumType *ETy = T->getAs<EnumType>())
8051    T = ETy->getDecl()->getIntegerType();
8052
8053  const BuiltinType *BTy = T->getAs<BuiltinType>();
8054  assert(BTy && "Unexpected signed integer type");
8055  switch (BTy->getKind()) {
8056  case BuiltinType::Char_S:
8057  case BuiltinType::SChar:
8058    return UnsignedCharTy;
8059  case BuiltinType::Short:
8060    return UnsignedShortTy;
8061  case BuiltinType::Int:
8062    return UnsignedIntTy;
8063  case BuiltinType::Long:
8064    return UnsignedLongTy;
8065  case BuiltinType::LongLong:
8066    return UnsignedLongLongTy;
8067  case BuiltinType::Int128:
8068    return UnsignedInt128Ty;
8069  default:
8070    llvm_unreachable("Unexpected signed integer type");
8071  }
8072}
8073
8074ASTMutationListener::~ASTMutationListener() { }
8075
8076void ASTMutationListener::DeducedReturnType(const FunctionDecl *FD,
8077                                            QualType ReturnType) {}
8078
8079//===----------------------------------------------------------------------===//
8080//                          Builtin Type Computation
8081//===----------------------------------------------------------------------===//
8082
8083/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
8084/// pointer over the consumed characters.  This returns the resultant type.  If
8085/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
8086/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
8087/// a vector of "i*".
8088///
8089/// RequiresICE is filled in on return to indicate whether the value is required
8090/// to be an Integer Constant Expression.
8091static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
8092                                  ASTContext::GetBuiltinTypeError &Error,
8093                                  bool &RequiresICE,
8094                                  bool AllowTypeModifiers) {
8095  // Modifiers.
8096  int HowLong = 0;
8097  bool Signed = false, Unsigned = false;
8098  RequiresICE = false;
8099
8100  // Read the prefixed modifiers first.
8101  bool Done = false;
8102  while (!Done) {
8103    switch (*Str++) {
8104    default: Done = true; --Str; break;
8105    case 'I':
8106      RequiresICE = true;
8107      break;
8108    case 'S':
8109      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
8110      assert(!Signed && "Can't use 'S' modifier multiple times!");
8111      Signed = true;
8112      break;
8113    case 'U':
8114      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
8115      assert(!Unsigned && "Can't use 'U' modifier multiple times!");
8116      Unsigned = true;
8117      break;
8118    case 'L':
8119      assert(HowLong <= 2 && "Can't have LLLL modifier");
8120      ++HowLong;
8121      break;
8122    case 'W':
8123      // This modifier represents int64 type.
8124      assert(HowLong == 0 && "Can't use both 'L' and 'W' modifiers!");
8125      switch (Context.getTargetInfo().getInt64Type()) {
8126      default:
8127        llvm_unreachable("Unexpected integer type");
8128      case TargetInfo::SignedLong:
8129        HowLong = 1;
8130        break;
8131      case TargetInfo::SignedLongLong:
8132        HowLong = 2;
8133        break;
8134      }
8135    }
8136  }
8137
8138  QualType Type;
8139
8140  // Read the base type.
8141  switch (*Str++) {
8142  default: llvm_unreachable("Unknown builtin type letter!");
8143  case 'v':
8144    assert(HowLong == 0 && !Signed && !Unsigned &&
8145           "Bad modifiers used with 'v'!");
8146    Type = Context.VoidTy;
8147    break;
8148  case 'h':
8149    assert(HowLong == 0 && !Signed && !Unsigned &&
8150           "Bad modifiers used with 'h'!");
8151    Type = Context.HalfTy;
8152    break;
8153  case 'f':
8154    assert(HowLong == 0 && !Signed && !Unsigned &&
8155           "Bad modifiers used with 'f'!");
8156    Type = Context.FloatTy;
8157    break;
8158  case 'd':
8159    assert(HowLong < 2 && !Signed && !Unsigned &&
8160           "Bad modifiers used with 'd'!");
8161    if (HowLong)
8162      Type = Context.LongDoubleTy;
8163    else
8164      Type = Context.DoubleTy;
8165    break;
8166  case 's':
8167    assert(HowLong == 0 && "Bad modifiers used with 's'!");
8168    if (Unsigned)
8169      Type = Context.UnsignedShortTy;
8170    else
8171      Type = Context.ShortTy;
8172    break;
8173  case 'i':
8174    if (HowLong == 3)
8175      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
8176    else if (HowLong == 2)
8177      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
8178    else if (HowLong == 1)
8179      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
8180    else
8181      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
8182    break;
8183  case 'c':
8184    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
8185    if (Signed)
8186      Type = Context.SignedCharTy;
8187    else if (Unsigned)
8188      Type = Context.UnsignedCharTy;
8189    else
8190      Type = Context.CharTy;
8191    break;
8192  case 'b': // boolean
8193    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
8194    Type = Context.BoolTy;
8195    break;
8196  case 'z':  // size_t.
8197    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
8198    Type = Context.getSizeType();
8199    break;
8200  case 'F':
8201    Type = Context.getCFConstantStringType();
8202    break;
8203  case 'G':
8204    Type = Context.getObjCIdType();
8205    break;
8206  case 'H':
8207    Type = Context.getObjCSelType();
8208    break;
8209  case 'M':
8210    Type = Context.getObjCSuperType();
8211    break;
8212  case 'a':
8213    Type = Context.getBuiltinVaListType();
8214    assert(!Type.isNull() && "builtin va list type not initialized!");
8215    break;
8216  case 'A':
8217    // This is a "reference" to a va_list; however, what exactly
8218    // this means depends on how va_list is defined. There are two
8219    // different kinds of va_list: ones passed by value, and ones
8220    // passed by reference.  An example of a by-value va_list is
8221    // x86, where va_list is a char*. An example of by-ref va_list
8222    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
8223    // we want this argument to be a char*&; for x86-64, we want
8224    // it to be a __va_list_tag*.
8225    Type = Context.getBuiltinVaListType();
8226    assert(!Type.isNull() && "builtin va list type not initialized!");
8227    if (Type->isArrayType())
8228      Type = Context.getArrayDecayedType(Type);
8229    else
8230      Type = Context.getLValueReferenceType(Type);
8231    break;
8232  case 'V': {
8233    char *End;
8234    unsigned NumElements = strtoul(Str, &End, 10);
8235    assert(End != Str && "Missing vector size");
8236    Str = End;
8237
8238    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
8239                                             RequiresICE, false);
8240    assert(!RequiresICE && "Can't require vector ICE");
8241
8242    // TODO: No way to make AltiVec vectors in builtins yet.
8243    Type = Context.getVectorType(ElementType, NumElements,
8244                                 VectorType::GenericVector);
8245    break;
8246  }
8247  case 'E': {
8248    char *End;
8249
8250    unsigned NumElements = strtoul(Str, &End, 10);
8251    assert(End != Str && "Missing vector size");
8252
8253    Str = End;
8254
8255    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
8256                                             false);
8257    Type = Context.getExtVectorType(ElementType, NumElements);
8258    break;
8259  }
8260  case 'X': {
8261    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
8262                                             false);
8263    assert(!RequiresICE && "Can't require complex ICE");
8264    Type = Context.getComplexType(ElementType);
8265    break;
8266  }
8267  case 'Y' : {
8268    Type = Context.getPointerDiffType();
8269    break;
8270  }
8271  case 'P':
8272    Type = Context.getFILEType();
8273    if (Type.isNull()) {
8274      Error = ASTContext::GE_Missing_stdio;
8275      return QualType();
8276    }
8277    break;
8278  case 'J':
8279    if (Signed)
8280      Type = Context.getsigjmp_bufType();
8281    else
8282      Type = Context.getjmp_bufType();
8283
8284    if (Type.isNull()) {
8285      Error = ASTContext::GE_Missing_setjmp;
8286      return QualType();
8287    }
8288    break;
8289  case 'K':
8290    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'K'!");
8291    Type = Context.getucontext_tType();
8292
8293    if (Type.isNull()) {
8294      Error = ASTContext::GE_Missing_ucontext;
8295      return QualType();
8296    }
8297    break;
8298  case 'p':
8299    Type = Context.getProcessIDType();
8300    break;
8301  }
8302
8303  // If there are modifiers and if we're allowed to parse them, go for it.
8304  Done = !AllowTypeModifiers;
8305  while (!Done) {
8306    switch (char c = *Str++) {
8307    default: Done = true; --Str; break;
8308    case '*':
8309    case '&': {
8310      // Both pointers and references can have their pointee types
8311      // qualified with an address space.
8312      char *End;
8313      unsigned AddrSpace = strtoul(Str, &End, 10);
8314      if (End != Str && AddrSpace != 0) {
8315        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
8316        Str = End;
8317      }
8318      if (c == '*')
8319        Type = Context.getPointerType(Type);
8320      else
8321        Type = Context.getLValueReferenceType(Type);
8322      break;
8323    }
8324    // FIXME: There's no way to have a built-in with an rvalue ref arg.
8325    case 'C':
8326      Type = Type.withConst();
8327      break;
8328    case 'D':
8329      Type = Context.getVolatileType(Type);
8330      break;
8331    case 'R':
8332      Type = Type.withRestrict();
8333      break;
8334    }
8335  }
8336
8337  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
8338         "Integer constant 'I' type must be an integer");
8339
8340  return Type;
8341}
8342
8343/// GetBuiltinType - Return the type for the specified builtin.
8344QualType ASTContext::GetBuiltinType(unsigned Id,
8345                                    GetBuiltinTypeError &Error,
8346                                    unsigned *IntegerConstantArgs) const {
8347  const char *TypeStr = BuiltinInfo.getTypeString(Id);
8348
8349  SmallVector<QualType, 8> ArgTypes;
8350
8351  bool RequiresICE = false;
8352  Error = GE_None;
8353  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
8354                                       RequiresICE, true);
8355  if (Error != GE_None)
8356    return QualType();
8357
8358  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
8359
8360  while (TypeStr[0] && TypeStr[0] != '.') {
8361    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
8362    if (Error != GE_None)
8363      return QualType();
8364
8365    // If this argument is required to be an IntegerConstantExpression and the
8366    // caller cares, fill in the bitmask we return.
8367    if (RequiresICE && IntegerConstantArgs)
8368      *IntegerConstantArgs |= 1 << ArgTypes.size();
8369
8370    // Do array -> pointer decay.  The builtin should use the decayed type.
8371    if (Ty->isArrayType())
8372      Ty = getArrayDecayedType(Ty);
8373
8374    ArgTypes.push_back(Ty);
8375  }
8376
8377  if (Id == Builtin::BI__GetExceptionInfo)
8378    return QualType();
8379
8380  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
8381         "'.' should only occur at end of builtin type list!");
8382
8383  FunctionType::ExtInfo EI(CC_C);
8384  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
8385
8386  bool Variadic = (TypeStr[0] == '.');
8387
8388  // We really shouldn't be making a no-proto type here, especially in C++.
8389  if (ArgTypes.empty() && Variadic)
8390    return getFunctionNoProtoType(ResType, EI);
8391
8392  FunctionProtoType::ExtProtoInfo EPI;
8393  EPI.ExtInfo = EI;
8394  EPI.Variadic = Variadic;
8395
8396  return getFunctionType(ResType, ArgTypes, EPI);
8397}
8398
8399static GVALinkage basicGVALinkageForFunction(const ASTContext &Context,
8400                                             const FunctionDecl *FD) {
8401  if (!FD->isExternallyVisible())
8402    return GVA_Internal;
8403
8404  GVALinkage External = GVA_StrongExternal;
8405  switch (FD->getTemplateSpecializationKind()) {
8406  case TSK_Undeclared:
8407  case TSK_ExplicitSpecialization:
8408    External = GVA_StrongExternal;
8409    break;
8410
8411  case TSK_ExplicitInstantiationDefinition:
8412    return GVA_StrongODR;
8413
8414  // C++11 [temp.explicit]p10:
8415  //   [ Note: The intent is that an inline function that is the subject of
8416  //   an explicit instantiation declaration will still be implicitly
8417  //   instantiated when used so that the body can be considered for
8418  //   inlining, but that no out-of-line copy of the inline function would be
8419  //   generated in the translation unit. -- end note ]
8420  case TSK_ExplicitInstantiationDeclaration:
8421    return GVA_AvailableExternally;
8422
8423  case TSK_ImplicitInstantiation:
8424    External = GVA_DiscardableODR;
8425    break;
8426  }
8427
8428  if (!FD->isInlined())
8429    return External;
8430
8431  if ((!Context.getLangOpts().CPlusPlus &&
8432       !Context.getTargetInfo().getCXXABI().isMicrosoft() &&
8433       !FD->hasAttr<DLLExportAttr>()) ||
8434      FD->hasAttr<GNUInlineAttr>()) {
8435    // FIXME: This doesn't match gcc's behavior for dllexport inline functions.
8436
8437    // GNU or C99 inline semantics. Determine whether this symbol should be
8438    // externally visible.
8439    if (FD->isInlineDefinitionExternallyVisible())
8440      return External;
8441
8442    // C99 inline semantics, where the symbol is not externally visible.
8443    return GVA_AvailableExternally;
8444  }
8445
8446  // Functions specified with extern and inline in -fms-compatibility mode
8447  // forcibly get emitted.  While the body of the function cannot be later
8448  // replaced, the function definition cannot be discarded.
8449  if (FD->isMSExternInline())
8450    return GVA_StrongODR;
8451
8452  return GVA_DiscardableODR;
8453}
8454
8455static GVALinkage adjustGVALinkageForAttributes(const ASTContext &Context,
8456                                                GVALinkage L, const Decl *D) {
8457  // See http://msdn.microsoft.com/en-us/library/xa0d9ste.aspx
8458  // dllexport/dllimport on inline functions.
8459  if (D->hasAttr<DLLImportAttr>()) {
8460    if (L == GVA_DiscardableODR || L == GVA_StrongODR)
8461      return GVA_AvailableExternally;
8462  } else if (D->hasAttr<DLLExportAttr>()) {
8463    if (L == GVA_DiscardableODR)
8464      return GVA_StrongODR;
8465  } else if (Context.getLangOpts().CUDA && Context.getLangOpts().CUDAIsDevice &&
8466             D->hasAttr<CUDAGlobalAttr>()) {
8467    // Device-side functions with __global__ attribute must always be
8468    // visible externally so they can be launched from host.
8469    if (L == GVA_DiscardableODR || L == GVA_Internal)
8470      return GVA_StrongODR;
8471  }
8472  return L;
8473}
8474
8475GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) const {
8476  return adjustGVALinkageForAttributes(
8477      *this, basicGVALinkageForFunction(*this, FD), FD);
8478}
8479
8480static GVALinkage basicGVALinkageForVariable(const ASTContext &Context,
8481                                             const VarDecl *VD) {
8482  if (!VD->isExternallyVisible())
8483    return GVA_Internal;
8484
8485  if (VD->isStaticLocal()) {
8486    GVALinkage StaticLocalLinkage = GVA_DiscardableODR;
8487    const DeclContext *LexicalContext = VD->getParentFunctionOrMethod();
8488    while (LexicalContext && !isa<FunctionDecl>(LexicalContext))
8489      LexicalContext = LexicalContext->getLexicalParent();
8490
8491    // Let the static local variable inherit its linkage from the nearest
8492    // enclosing function.
8493    if (LexicalContext)
8494      StaticLocalLinkage =
8495          Context.GetGVALinkageForFunction(cast<FunctionDecl>(LexicalContext));
8496
8497    // GVA_StrongODR function linkage is stronger than what we need,
8498    // downgrade to GVA_DiscardableODR.
8499    // This allows us to discard the variable if we never end up needing it.
8500    return StaticLocalLinkage == GVA_StrongODR ? GVA_DiscardableODR
8501                                               : StaticLocalLinkage;
8502  }
8503
8504  // MSVC treats in-class initialized static data members as definitions.
8505  // By giving them non-strong linkage, out-of-line definitions won't
8506  // cause link errors.
8507  if (Context.isMSStaticDataMemberInlineDefinition(VD))
8508    return GVA_DiscardableODR;
8509
8510  // Most non-template variables have strong linkage; inline variables are
8511  // linkonce_odr or (occasionally, for compatibility) weak_odr.
8512  GVALinkage StrongLinkage;
8513  switch (Context.getInlineVariableDefinitionKind(VD)) {
8514  case ASTContext::InlineVariableDefinitionKind::None:
8515    StrongLinkage = GVA_StrongExternal;
8516    break;
8517  case ASTContext::InlineVariableDefinitionKind::Weak:
8518  case ASTContext::InlineVariableDefinitionKind::WeakUnknown:
8519    StrongLinkage = GVA_DiscardableODR;
8520    break;
8521  case ASTContext::InlineVariableDefinitionKind::Strong:
8522    StrongLinkage = GVA_StrongODR;
8523    break;
8524  }
8525
8526  switch (VD->getTemplateSpecializationKind()) {
8527  case TSK_Undeclared:
8528    return StrongLinkage;
8529
8530  case TSK_ExplicitSpecialization:
8531    return Context.getTargetInfo().getCXXABI().isMicrosoft() &&
8532                   VD->isStaticDataMember()
8533               ? GVA_StrongODR
8534               : StrongLinkage;
8535
8536  case TSK_ExplicitInstantiationDefinition:
8537    return GVA_StrongODR;
8538
8539  case TSK_ExplicitInstantiationDeclaration:
8540    return GVA_AvailableExternally;
8541
8542  case TSK_ImplicitInstantiation:
8543    return GVA_DiscardableODR;
8544  }
8545
8546  llvm_unreachable("Invalid Linkage!");
8547}
8548
8549GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
8550  return adjustGVALinkageForAttributes(
8551      *this, basicGVALinkageForVariable(*this, VD), VD);
8552}
8553
8554bool ASTContext::DeclMustBeEmitted(const Decl *D) {
8555  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
8556    if (!VD->isFileVarDecl())
8557      return false;
8558    // Global named register variables (GNU extension) are never emitted.
8559    if (VD->getStorageClass() == SC_Register)
8560      return false;
8561    if (VD->getDescribedVarTemplate() ||
8562        isa<VarTemplatePartialSpecializationDecl>(VD))
8563      return false;
8564  } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
8565    // We never need to emit an uninstantiated function template.
8566    if (FD->getTemplatedKind() == FunctionDecl::TK_FunctionTemplate)
8567      return false;
8568  } else if (isa<PragmaCommentDecl>(D))
8569    return true;
8570  else if (isa<OMPThreadPrivateDecl>(D) ||
8571           D->hasAttr<OMPDeclareTargetDeclAttr>())
8572    return true;
8573  else if (isa<PragmaDetectMismatchDecl>(D))
8574    return true;
8575  else if (isa<OMPThreadPrivateDecl>(D))
8576    return !D->getDeclContext()->isDependentContext();
8577  else if (isa<OMPDeclareReductionDecl>(D))
8578    return !D->getDeclContext()->isDependentContext();
8579  else
8580    return false;
8581
8582  // If this is a member of a class template, we do not need to emit it.
8583  if (D->getDeclContext()->isDependentContext())
8584    return false;
8585
8586  // Weak references don't produce any output by themselves.
8587  if (D->hasAttr<WeakRefAttr>())
8588    return false;
8589
8590  // Aliases and used decls are required.
8591  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
8592    return true;
8593
8594  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
8595    // Forward declarations aren't required.
8596    if (!FD->doesThisDeclarationHaveABody())
8597      return FD->doesDeclarationForceExternallyVisibleDefinition();
8598
8599    // Constructors and destructors are required.
8600    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
8601      return true;
8602
8603    // The key function for a class is required.  This rule only comes
8604    // into play when inline functions can be key functions, though.
8605    if (getTargetInfo().getCXXABI().canKeyFunctionBeInline()) {
8606      if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
8607        const CXXRecordDecl *RD = MD->getParent();
8608        if (MD->isOutOfLine() && RD->isDynamicClass()) {
8609          const CXXMethodDecl *KeyFunc = getCurrentKeyFunction(RD);
8610          if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
8611            return true;
8612        }
8613      }
8614    }
8615
8616    GVALinkage Linkage = GetGVALinkageForFunction(FD);
8617
8618    // static, static inline, always_inline, and extern inline functions can
8619    // always be deferred.  Normal inline functions can be deferred in C99/C++.
8620    // Implicit template instantiations can also be deferred in C++.
8621    if (Linkage == GVA_Internal || Linkage == GVA_AvailableExternally ||
8622        Linkage == GVA_DiscardableODR)
8623      return false;
8624    return true;
8625  }
8626
8627  const VarDecl *VD = cast<VarDecl>(D);
8628  assert(VD->isFileVarDecl() && "Expected file scoped var");
8629
8630  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly &&
8631      !isMSStaticDataMemberInlineDefinition(VD))
8632    return false;
8633
8634  // Variables that can be needed in other TUs are required.
8635  GVALinkage L = GetGVALinkageForVariable(VD);
8636  if (L != GVA_Internal && L != GVA_AvailableExternally &&
8637      L != GVA_DiscardableODR)
8638    return true;
8639
8640  // Variables that have destruction with side-effects are required.
8641  if (VD->getType().isDestructedType())
8642    return true;
8643
8644  // Variables that have initialization with side-effects are required.
8645  if (VD->getInit() && VD->getInit()->HasSideEffects(*this) &&
8646      !VD->evaluateValue())
8647    return true;
8648
8649  return false;
8650}
8651
8652CallingConv ASTContext::getDefaultCallingConvention(bool IsVariadic,
8653                                                    bool IsCXXMethod) const {
8654  // Pass through to the C++ ABI object
8655  if (IsCXXMethod)
8656    return ABI->getDefaultMethodCallConv(IsVariadic);
8657
8658  switch (LangOpts.getDefaultCallingConv()) {
8659  case LangOptions::DCC_None:
8660    break;
8661  case LangOptions::DCC_CDecl:
8662    return CC_C;
8663  case LangOptions::DCC_FastCall:
8664    if (getTargetInfo().hasFeature("sse2"))
8665      return CC_X86FastCall;
8666    break;
8667  case LangOptions::DCC_StdCall:
8668    if (!IsVariadic)
8669      return CC_X86StdCall;
8670    break;
8671  case LangOptions::DCC_VectorCall:
8672    // __vectorcall cannot be applied to variadic functions.
8673    if (!IsVariadic)
8674      return CC_X86VectorCall;
8675    break;
8676  }
8677  return Target->getDefaultCallingConv(TargetInfo::CCMT_Unknown);
8678}
8679
8680bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
8681  // Pass through to the C++ ABI object
8682  return ABI->isNearlyEmpty(RD);
8683}
8684
8685VTableContextBase *ASTContext::getVTableContext() {
8686  if (!VTContext.get()) {
8687    if (Target->getCXXABI().isMicrosoft())
8688      VTContext.reset(new MicrosoftVTableContext(*this));
8689    else
8690      VTContext.reset(new ItaniumVTableContext(*this));
8691  }
8692  return VTContext.get();
8693}
8694
8695MangleContext *ASTContext::createMangleContext() {
8696  switch (Target->getCXXABI().getKind()) {
8697  case TargetCXXABI::GenericAArch64:
8698  case TargetCXXABI::GenericItanium:
8699  case TargetCXXABI::GenericARM:
8700  case TargetCXXABI::GenericMIPS:
8701  case TargetCXXABI::iOS:
8702  case TargetCXXABI::iOS64:
8703  case TargetCXXABI::WebAssembly:
8704  case TargetCXXABI::WatchOS:
8705    return ItaniumMangleContext::create(*this, getDiagnostics());
8706  case TargetCXXABI::Microsoft:
8707    return MicrosoftMangleContext::create(*this, getDiagnostics());
8708  }
8709  llvm_unreachable("Unsupported ABI");
8710}
8711
8712CXXABI::~CXXABI() {}
8713
8714size_t ASTContext::getSideTableAllocatedMemory() const {
8715  return ASTRecordLayouts.getMemorySize() +
8716         llvm::capacity_in_bytes(ObjCLayouts) +
8717         llvm::capacity_in_bytes(KeyFunctions) +
8718         llvm::capacity_in_bytes(ObjCImpls) +
8719         llvm::capacity_in_bytes(BlockVarCopyInits) +
8720         llvm::capacity_in_bytes(DeclAttrs) +
8721         llvm::capacity_in_bytes(TemplateOrInstantiation) +
8722         llvm::capacity_in_bytes(InstantiatedFromUsingDecl) +
8723         llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl) +
8724         llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl) +
8725         llvm::capacity_in_bytes(OverriddenMethods) +
8726         llvm::capacity_in_bytes(Types) +
8727         llvm::capacity_in_bytes(VariableArrayTypes) +
8728         llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
8729}
8730
8731/// getIntTypeForBitwidth -
8732/// sets integer QualTy according to specified details:
8733/// bitwidth, signed/unsigned.
8734/// Returns empty type if there is no appropriate target types.
8735QualType ASTContext::getIntTypeForBitwidth(unsigned DestWidth,
8736                                           unsigned Signed) const {
8737  TargetInfo::IntType Ty = getTargetInfo().getIntTypeByWidth(DestWidth, Signed);
8738  CanQualType QualTy = getFromTargetType(Ty);
8739  if (!QualTy && DestWidth == 128)
8740    return Signed ? Int128Ty : UnsignedInt128Ty;
8741  return QualTy;
8742}
8743
8744/// getRealTypeForBitwidth -
8745/// sets floating point QualTy according to specified bitwidth.
8746/// Returns empty type if there is no appropriate target types.
8747QualType ASTContext::getRealTypeForBitwidth(unsigned DestWidth) const {
8748  TargetInfo::RealType Ty = getTargetInfo().getRealTypeByWidth(DestWidth);
8749  switch (Ty) {
8750  case TargetInfo::Float:
8751    return FloatTy;
8752  case TargetInfo::Double:
8753    return DoubleTy;
8754  case TargetInfo::LongDouble:
8755    return LongDoubleTy;
8756  case TargetInfo::Float128:
8757    return Float128Ty;
8758  case TargetInfo::NoFloat:
8759    return QualType();
8760  }
8761
8762  llvm_unreachable("Unhandled TargetInfo::RealType value");
8763}
8764
8765void ASTContext::setManglingNumber(const NamedDecl *ND, unsigned Number) {
8766  if (Number > 1)
8767    MangleNumbers[ND] = Number;
8768}
8769
8770unsigned ASTContext::getManglingNumber(const NamedDecl *ND) const {
8771  auto I = MangleNumbers.find(ND);
8772  return I != MangleNumbers.end() ? I->second : 1;
8773}
8774
8775void ASTContext::setStaticLocalNumber(const VarDecl *VD, unsigned Number) {
8776  if (Number > 1)
8777    StaticLocalNumbers[VD] = Number;
8778}
8779
8780unsigned ASTContext::getStaticLocalNumber(const VarDecl *VD) const {
8781  auto I = StaticLocalNumbers.find(VD);
8782  return I != StaticLocalNumbers.end() ? I->second : 1;
8783}
8784
8785MangleNumberingContext &
8786ASTContext::getManglingNumberContext(const DeclContext *DC) {
8787  assert(LangOpts.CPlusPlus);  // We don't need mangling numbers for plain C.
8788  MangleNumberingContext *&MCtx = MangleNumberingContexts[DC];
8789  if (!MCtx)
8790    MCtx = createMangleNumberingContext();
8791  return *MCtx;
8792}
8793
8794MangleNumberingContext *ASTContext::createMangleNumberingContext() const {
8795  return ABI->createMangleNumberingContext();
8796}
8797
8798const CXXConstructorDecl *
8799ASTContext::getCopyConstructorForExceptionObject(CXXRecordDecl *RD) {
8800  return ABI->getCopyConstructorForExceptionObject(
8801      cast<CXXRecordDecl>(RD->getFirstDecl()));
8802}
8803
8804void ASTContext::addCopyConstructorForExceptionObject(CXXRecordDecl *RD,
8805                                                      CXXConstructorDecl *CD) {
8806  return ABI->addCopyConstructorForExceptionObject(
8807      cast<CXXRecordDecl>(RD->getFirstDecl()),
8808      cast<CXXConstructorDecl>(CD->getFirstDecl()));
8809}
8810
8811void ASTContext::addDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
8812                                                 unsigned ParmIdx, Expr *DAE) {
8813  ABI->addDefaultArgExprForConstructor(
8814      cast<CXXConstructorDecl>(CD->getFirstDecl()), ParmIdx, DAE);
8815}
8816
8817Expr *ASTContext::getDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
8818                                                  unsigned ParmIdx) {
8819  return ABI->getDefaultArgExprForConstructor(
8820      cast<CXXConstructorDecl>(CD->getFirstDecl()), ParmIdx);
8821}
8822
8823void ASTContext::addTypedefNameForUnnamedTagDecl(TagDecl *TD,
8824                                                 TypedefNameDecl *DD) {
8825  return ABI->addTypedefNameForUnnamedTagDecl(TD, DD);
8826}
8827
8828TypedefNameDecl *
8829ASTContext::getTypedefNameForUnnamedTagDecl(const TagDecl *TD) {
8830  return ABI->getTypedefNameForUnnamedTagDecl(TD);
8831}
8832
8833void ASTContext::addDeclaratorForUnnamedTagDecl(TagDecl *TD,
8834                                                DeclaratorDecl *DD) {
8835  return ABI->addDeclaratorForUnnamedTagDecl(TD, DD);
8836}
8837
8838DeclaratorDecl *ASTContext::getDeclaratorForUnnamedTagDecl(const TagDecl *TD) {
8839  return ABI->getDeclaratorForUnnamedTagDecl(TD);
8840}
8841
8842void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
8843  ParamIndices[D] = index;
8844}
8845
8846unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
8847  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
8848  assert(I != ParamIndices.end() &&
8849         "ParmIndices lacks entry set by ParmVarDecl");
8850  return I->second;
8851}
8852
8853APValue *
8854ASTContext::getMaterializedTemporaryValue(const MaterializeTemporaryExpr *E,
8855                                          bool MayCreate) {
8856  assert(E && E->getStorageDuration() == SD_Static &&
8857         "don't need to cache the computed value for this temporary");
8858  if (MayCreate) {
8859    APValue *&MTVI = MaterializedTemporaryValues[E];
8860    if (!MTVI)
8861      MTVI = new (*this) APValue;
8862    return MTVI;
8863  }
8864
8865  return MaterializedTemporaryValues.lookup(E);
8866}
8867
8868bool ASTContext::AtomicUsesUnsupportedLibcall(const AtomicExpr *E) const {
8869  const llvm::Triple &T = getTargetInfo().getTriple();
8870  if (!T.isOSDarwin())
8871    return false;
8872
8873  if (!(T.isiOS() && T.isOSVersionLT(7)) &&
8874      !(T.isMacOSX() && T.isOSVersionLT(10, 9)))
8875    return false;
8876
8877  QualType AtomicTy = E->getPtr()->getType()->getPointeeType();
8878  CharUnits sizeChars = getTypeSizeInChars(AtomicTy);
8879  uint64_t Size = sizeChars.getQuantity();
8880  CharUnits alignChars = getTypeAlignInChars(AtomicTy);
8881  unsigned Align = alignChars.getQuantity();
8882  unsigned MaxInlineWidthInBits = getTargetInfo().getMaxAtomicInlineWidth();
8883  return (Size != Align || toBits(sizeChars) > MaxInlineWidthInBits);
8884}
8885
8886namespace {
8887
8888ast_type_traits::DynTypedNode getSingleDynTypedNodeFromParentMap(
8889    ASTContext::ParentMapPointers::mapped_type U) {
8890  if (const auto *D = U.dyn_cast<const Decl *>())
8891    return ast_type_traits::DynTypedNode::create(*D);
8892  if (const auto *S = U.dyn_cast<const Stmt *>())
8893    return ast_type_traits::DynTypedNode::create(*S);
8894  return *U.get<ast_type_traits::DynTypedNode *>();
8895}
8896
8897/// Template specializations to abstract away from pointers and TypeLocs.
8898/// @{
8899template <typename T>
8900ast_type_traits::DynTypedNode createDynTypedNode(const T &Node) {
8901  return ast_type_traits::DynTypedNode::create(*Node);
8902}
8903template <>
8904ast_type_traits::DynTypedNode createDynTypedNode(const TypeLoc &Node) {
8905  return ast_type_traits::DynTypedNode::create(Node);
8906}
8907template <>
8908ast_type_traits::DynTypedNode
8909createDynTypedNode(const NestedNameSpecifierLoc &Node) {
8910  return ast_type_traits::DynTypedNode::create(Node);
8911}
8912/// @}
8913
8914  /// \brief A \c RecursiveASTVisitor that builds a map from nodes to their
8915  /// parents as defined by the \c RecursiveASTVisitor.
8916  ///
8917  /// Note that the relationship described here is purely in terms of AST
8918  /// traversal - there are other relationships (for example declaration context)
8919  /// in the AST that are better modeled by special matchers.
8920  ///
8921  /// FIXME: Currently only builds up the map using \c Stmt and \c Decl nodes.
8922  class ParentMapASTVisitor : public RecursiveASTVisitor<ParentMapASTVisitor> {
8923  public:
8924    /// \brief Builds and returns the translation unit's parent map.
8925    ///
8926    ///  The caller takes ownership of the returned \c ParentMap.
8927    static std::pair<ASTContext::ParentMapPointers *,
8928                     ASTContext::ParentMapOtherNodes *>
8929    buildMap(TranslationUnitDecl &TU) {
8930      ParentMapASTVisitor Visitor(new ASTContext::ParentMapPointers,
8931                                  new ASTContext::ParentMapOtherNodes);
8932      Visitor.TraverseDecl(&TU);
8933      return std::make_pair(Visitor.Parents, Visitor.OtherParents);
8934    }
8935
8936  private:
8937    typedef RecursiveASTVisitor<ParentMapASTVisitor> VisitorBase;
8938
8939    ParentMapASTVisitor(ASTContext::ParentMapPointers *Parents,
8940                        ASTContext::ParentMapOtherNodes *OtherParents)
8941        : Parents(Parents), OtherParents(OtherParents) {}
8942
8943    bool shouldVisitTemplateInstantiations() const {
8944      return true;
8945    }
8946    bool shouldVisitImplicitCode() const {
8947      return true;
8948    }
8949
8950    template <typename T, typename MapNodeTy, typename BaseTraverseFn,
8951              typename MapTy>
8952    bool TraverseNode(T Node, MapNodeTy MapNode,
8953                      BaseTraverseFn BaseTraverse, MapTy *Parents) {
8954      if (!Node)
8955        return true;
8956      if (ParentStack.size() > 0) {
8957        // FIXME: Currently we add the same parent multiple times, but only
8958        // when no memoization data is available for the type.
8959        // For example when we visit all subexpressions of template
8960        // instantiations; this is suboptimal, but benign: the only way to
8961        // visit those is with hasAncestor / hasParent, and those do not create
8962        // new matches.
8963        // The plan is to enable DynTypedNode to be storable in a map or hash
8964        // map. The main problem there is to implement hash functions /
8965        // comparison operators for all types that DynTypedNode supports that
8966        // do not have pointer identity.
8967        auto &NodeOrVector = (*Parents)[MapNode];
8968        if (NodeOrVector.isNull()) {
8969          if (const auto *D = ParentStack.back().get<Decl>())
8970            NodeOrVector = D;
8971          else if (const auto *S = ParentStack.back().get<Stmt>())
8972            NodeOrVector = S;
8973          else
8974            NodeOrVector =
8975                new ast_type_traits::DynTypedNode(ParentStack.back());
8976        } else {
8977          if (!NodeOrVector.template is<ASTContext::ParentVector *>()) {
8978            auto *Vector = new ASTContext::ParentVector(
8979                1, getSingleDynTypedNodeFromParentMap(NodeOrVector));
8980            if (auto *Node =
8981                    NodeOrVector
8982                        .template dyn_cast<ast_type_traits::DynTypedNode *>())
8983              delete Node;
8984            NodeOrVector = Vector;
8985          }
8986
8987          auto *Vector =
8988              NodeOrVector.template get<ASTContext::ParentVector *>();
8989          // Skip duplicates for types that have memoization data.
8990          // We must check that the type has memoization data before calling
8991          // std::find() because DynTypedNode::operator== can't compare all
8992          // types.
8993          bool Found = ParentStack.back().getMemoizationData() &&
8994                       std::find(Vector->begin(), Vector->end(),
8995                                 ParentStack.back()) != Vector->end();
8996          if (!Found)
8997            Vector->push_back(ParentStack.back());
8998        }
8999      }
9000      ParentStack.push_back(createDynTypedNode(Node));
9001      bool Result = BaseTraverse();
9002      ParentStack.pop_back();
9003      return Result;
9004    }
9005
9006    bool TraverseDecl(Decl *DeclNode) {
9007      return TraverseNode(DeclNode, DeclNode,
9008                          [&] { return VisitorBase::TraverseDecl(DeclNode); },
9009                          Parents);
9010    }
9011
9012    bool TraverseStmt(Stmt *StmtNode) {
9013      return TraverseNode(StmtNode, StmtNode,
9014                          [&] { return VisitorBase::TraverseStmt(StmtNode); },
9015                          Parents);
9016    }
9017
9018    bool TraverseTypeLoc(TypeLoc TypeLocNode) {
9019      return TraverseNode(
9020          TypeLocNode, ast_type_traits::DynTypedNode::create(TypeLocNode),
9021          [&] { return VisitorBase::TraverseTypeLoc(TypeLocNode); },
9022          OtherParents);
9023    }
9024
9025    bool TraverseNestedNameSpecifierLoc(NestedNameSpecifierLoc NNSLocNode) {
9026      return TraverseNode(
9027          NNSLocNode, ast_type_traits::DynTypedNode::create(NNSLocNode),
9028          [&] {
9029            return VisitorBase::TraverseNestedNameSpecifierLoc(NNSLocNode);
9030          },
9031          OtherParents);
9032    }
9033
9034    ASTContext::ParentMapPointers *Parents;
9035    ASTContext::ParentMapOtherNodes *OtherParents;
9036    llvm::SmallVector<ast_type_traits::DynTypedNode, 16> ParentStack;
9037
9038    friend class RecursiveASTVisitor<ParentMapASTVisitor>;
9039  };
9040
9041} // anonymous namespace
9042
9043template <typename NodeTy, typename MapTy>
9044static ASTContext::DynTypedNodeList getDynNodeFromMap(const NodeTy &Node,
9045                                                      const MapTy &Map) {
9046  auto I = Map.find(Node);
9047  if (I == Map.end()) {
9048    return llvm::ArrayRef<ast_type_traits::DynTypedNode>();
9049  }
9050  if (auto *V = I->second.template dyn_cast<ASTContext::ParentVector *>()) {
9051    return llvm::makeArrayRef(*V);
9052  }
9053  return getSingleDynTypedNodeFromParentMap(I->second);
9054}
9055
9056ASTContext::DynTypedNodeList
9057ASTContext::getParents(const ast_type_traits::DynTypedNode &Node) {
9058  if (!PointerParents) {
9059    // We always need to run over the whole translation unit, as
9060    // hasAncestor can escape any subtree.
9061    auto Maps = ParentMapASTVisitor::buildMap(*getTranslationUnitDecl());
9062    PointerParents.reset(Maps.first);
9063    OtherParents.reset(Maps.second);
9064  }
9065  if (Node.getNodeKind().hasPointerIdentity())
9066    return getDynNodeFromMap(Node.getMemoizationData(), *PointerParents);
9067  return getDynNodeFromMap(Node, *OtherParents);
9068}
9069
9070bool
9071ASTContext::ObjCMethodsAreEqual(const ObjCMethodDecl *MethodDecl,
9072                                const ObjCMethodDecl *MethodImpl) {
9073  // No point trying to match an unavailable/deprecated mothod.
9074  if (MethodDecl->hasAttr<UnavailableAttr>()
9075      || MethodDecl->hasAttr<DeprecatedAttr>())
9076    return false;
9077  if (MethodDecl->getObjCDeclQualifier() !=
9078      MethodImpl->getObjCDeclQualifier())
9079    return false;
9080  if (!hasSameType(MethodDecl->getReturnType(), MethodImpl->getReturnType()))
9081    return false;
9082
9083  if (MethodDecl->param_size() != MethodImpl->param_size())
9084    return false;
9085
9086  for (ObjCMethodDecl::param_const_iterator IM = MethodImpl->param_begin(),
9087       IF = MethodDecl->param_begin(), EM = MethodImpl->param_end(),
9088       EF = MethodDecl->param_end();
9089       IM != EM && IF != EF; ++IM, ++IF) {
9090    const ParmVarDecl *DeclVar = (*IF);
9091    const ParmVarDecl *ImplVar = (*IM);
9092    if (ImplVar->getObjCDeclQualifier() != DeclVar->getObjCDeclQualifier())
9093      return false;
9094    if (!hasSameType(DeclVar->getType(), ImplVar->getType()))
9095      return false;
9096  }
9097  return (MethodDecl->isVariadic() == MethodImpl->isVariadic());
9098
9099}
9100
9101// Explicitly instantiate this in case a Redeclarable<T> is used from a TU that
9102// doesn't include ASTContext.h
9103template
9104clang::LazyGenerationalUpdatePtr<
9105    const Decl *, Decl *, &ExternalASTSource::CompleteRedeclChain>::ValueType
9106clang::LazyGenerationalUpdatePtr<
9107    const Decl *, Decl *, &ExternalASTSource::CompleteRedeclChain>::makeValue(
9108        const clang::ASTContext &Ctx, Decl *Value);
9109