1//===--- ASTContext.cpp - Context to hold long-lived AST nodes ------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements the ASTContext interface.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/AST/ASTContext.h"
15#include "CXXABI.h"
16#include "clang/AST/ASTMutationListener.h"
17#include "clang/AST/Attr.h"
18#include "clang/AST/CharUnits.h"
19#include "clang/AST/Comment.h"
20#include "clang/AST/CommentCommandTraits.h"
21#include "clang/AST/DeclCXX.h"
22#include "clang/AST/DeclObjC.h"
23#include "clang/AST/DeclTemplate.h"
24#include "clang/AST/Expr.h"
25#include "clang/AST/ExprCXX.h"
26#include "clang/AST/ExternalASTSource.h"
27#include "clang/AST/Mangle.h"
28#include "clang/AST/MangleNumberingContext.h"
29#include "clang/AST/RecordLayout.h"
30#include "clang/AST/RecursiveASTVisitor.h"
31#include "clang/AST/TypeLoc.h"
32#include "clang/AST/VTableBuilder.h"
33#include "clang/Basic/Builtins.h"
34#include "clang/Basic/SourceManager.h"
35#include "clang/Basic/TargetInfo.h"
36#include "llvm/ADT/SmallString.h"
37#include "llvm/ADT/StringExtras.h"
38#include "llvm/ADT/Triple.h"
39#include "llvm/Support/Capacity.h"
40#include "llvm/Support/MathExtras.h"
41#include "llvm/Support/raw_ostream.h"
42#include <map>
43
44using namespace clang;
45
46unsigned ASTContext::NumImplicitDefaultConstructors;
47unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
48unsigned ASTContext::NumImplicitCopyConstructors;
49unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
50unsigned ASTContext::NumImplicitMoveConstructors;
51unsigned ASTContext::NumImplicitMoveConstructorsDeclared;
52unsigned ASTContext::NumImplicitCopyAssignmentOperators;
53unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
54unsigned ASTContext::NumImplicitMoveAssignmentOperators;
55unsigned ASTContext::NumImplicitMoveAssignmentOperatorsDeclared;
56unsigned ASTContext::NumImplicitDestructors;
57unsigned ASTContext::NumImplicitDestructorsDeclared;
58
59enum FloatingRank {
60  HalfRank, FloatRank, DoubleRank, LongDoubleRank
61};
62
63RawComment *ASTContext::getRawCommentForDeclNoCache(const Decl *D) const {
64  if (!CommentsLoaded && ExternalSource) {
65    ExternalSource->ReadComments();
66
67#ifndef NDEBUG
68    ArrayRef<RawComment *> RawComments = Comments.getComments();
69    assert(std::is_sorted(RawComments.begin(), RawComments.end(),
70                          BeforeThanCompare<RawComment>(SourceMgr)));
71#endif
72
73    CommentsLoaded = true;
74  }
75
76  assert(D);
77
78  // User can not attach documentation to implicit declarations.
79  if (D->isImplicit())
80    return nullptr;
81
82  // User can not attach documentation to implicit instantiations.
83  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
84    if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
85      return nullptr;
86  }
87
88  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
89    if (VD->isStaticDataMember() &&
90        VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
91      return nullptr;
92  }
93
94  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(D)) {
95    if (CRD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
96      return nullptr;
97  }
98
99  if (const ClassTemplateSpecializationDecl *CTSD =
100          dyn_cast<ClassTemplateSpecializationDecl>(D)) {
101    TemplateSpecializationKind TSK = CTSD->getSpecializationKind();
102    if (TSK == TSK_ImplicitInstantiation ||
103        TSK == TSK_Undeclared)
104      return nullptr;
105  }
106
107  if (const EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
108    if (ED->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
109      return nullptr;
110  }
111  if (const TagDecl *TD = dyn_cast<TagDecl>(D)) {
112    // When tag declaration (but not definition!) is part of the
113    // decl-specifier-seq of some other declaration, it doesn't get comment
114    if (TD->isEmbeddedInDeclarator() && !TD->isCompleteDefinition())
115      return nullptr;
116  }
117  // TODO: handle comments for function parameters properly.
118  if (isa<ParmVarDecl>(D))
119    return nullptr;
120
121  // TODO: we could look up template parameter documentation in the template
122  // documentation.
123  if (isa<TemplateTypeParmDecl>(D) ||
124      isa<NonTypeTemplateParmDecl>(D) ||
125      isa<TemplateTemplateParmDecl>(D))
126    return nullptr;
127
128  ArrayRef<RawComment *> RawComments = Comments.getComments();
129
130  // If there are no comments anywhere, we won't find anything.
131  if (RawComments.empty())
132    return nullptr;
133
134  // Find declaration location.
135  // For Objective-C declarations we generally don't expect to have multiple
136  // declarators, thus use declaration starting location as the "declaration
137  // location".
138  // For all other declarations multiple declarators are used quite frequently,
139  // so we use the location of the identifier as the "declaration location".
140  SourceLocation DeclLoc;
141  if (isa<ObjCMethodDecl>(D) || isa<ObjCContainerDecl>(D) ||
142      isa<ObjCPropertyDecl>(D) ||
143      isa<RedeclarableTemplateDecl>(D) ||
144      isa<ClassTemplateSpecializationDecl>(D))
145    DeclLoc = D->getLocStart();
146  else {
147    DeclLoc = D->getLocation();
148    if (DeclLoc.isMacroID()) {
149      if (isa<TypedefDecl>(D)) {
150        // If location of the typedef name is in a macro, it is because being
151        // declared via a macro. Try using declaration's starting location as
152        // the "declaration location".
153        DeclLoc = D->getLocStart();
154      } else if (const TagDecl *TD = dyn_cast<TagDecl>(D)) {
155        // If location of the tag decl is inside a macro, but the spelling of
156        // the tag name comes from a macro argument, it looks like a special
157        // macro like NS_ENUM is being used to define the tag decl.  In that
158        // case, adjust the source location to the expansion loc so that we can
159        // attach the comment to the tag decl.
160        if (SourceMgr.isMacroArgExpansion(DeclLoc) &&
161            TD->isCompleteDefinition())
162          DeclLoc = SourceMgr.getExpansionLoc(DeclLoc);
163      }
164    }
165  }
166
167  // If the declaration doesn't map directly to a location in a file, we
168  // can't find the comment.
169  if (DeclLoc.isInvalid() || !DeclLoc.isFileID())
170    return nullptr;
171
172  // Find the comment that occurs just after this declaration.
173  ArrayRef<RawComment *>::iterator Comment;
174  {
175    // When searching for comments during parsing, the comment we are looking
176    // for is usually among the last two comments we parsed -- check them
177    // first.
178    RawComment CommentAtDeclLoc(
179        SourceMgr, SourceRange(DeclLoc), false,
180        LangOpts.CommentOpts.ParseAllComments);
181    BeforeThanCompare<RawComment> Compare(SourceMgr);
182    ArrayRef<RawComment *>::iterator MaybeBeforeDecl = RawComments.end() - 1;
183    bool Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
184    if (!Found && RawComments.size() >= 2) {
185      MaybeBeforeDecl--;
186      Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
187    }
188
189    if (Found) {
190      Comment = MaybeBeforeDecl + 1;
191      assert(Comment == std::lower_bound(RawComments.begin(), RawComments.end(),
192                                         &CommentAtDeclLoc, Compare));
193    } else {
194      // Slow path.
195      Comment = std::lower_bound(RawComments.begin(), RawComments.end(),
196                                 &CommentAtDeclLoc, Compare);
197    }
198  }
199
200  // Decompose the location for the declaration and find the beginning of the
201  // file buffer.
202  std::pair<FileID, unsigned> DeclLocDecomp = SourceMgr.getDecomposedLoc(DeclLoc);
203
204  // First check whether we have a trailing comment.
205  if (Comment != RawComments.end() &&
206      (*Comment)->isDocumentation() && (*Comment)->isTrailingComment() &&
207      (isa<FieldDecl>(D) || isa<EnumConstantDecl>(D) || isa<VarDecl>(D) ||
208       isa<ObjCMethodDecl>(D) || isa<ObjCPropertyDecl>(D))) {
209    std::pair<FileID, unsigned> CommentBeginDecomp
210      = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getBegin());
211    // Check that Doxygen trailing comment comes after the declaration, starts
212    // on the same line and in the same file as the declaration.
213    if (DeclLocDecomp.first == CommentBeginDecomp.first &&
214        SourceMgr.getLineNumber(DeclLocDecomp.first, DeclLocDecomp.second)
215          == SourceMgr.getLineNumber(CommentBeginDecomp.first,
216                                     CommentBeginDecomp.second)) {
217      return *Comment;
218    }
219  }
220
221  // The comment just after the declaration was not a trailing comment.
222  // Let's look at the previous comment.
223  if (Comment == RawComments.begin())
224    return nullptr;
225  --Comment;
226
227  // Check that we actually have a non-member Doxygen comment.
228  if (!(*Comment)->isDocumentation() || (*Comment)->isTrailingComment())
229    return nullptr;
230
231  // Decompose the end of the comment.
232  std::pair<FileID, unsigned> CommentEndDecomp
233    = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getEnd());
234
235  // If the comment and the declaration aren't in the same file, then they
236  // aren't related.
237  if (DeclLocDecomp.first != CommentEndDecomp.first)
238    return nullptr;
239
240  // Get the corresponding buffer.
241  bool Invalid = false;
242  const char *Buffer = SourceMgr.getBufferData(DeclLocDecomp.first,
243                                               &Invalid).data();
244  if (Invalid)
245    return nullptr;
246
247  // Extract text between the comment and declaration.
248  StringRef Text(Buffer + CommentEndDecomp.second,
249                 DeclLocDecomp.second - CommentEndDecomp.second);
250
251  // There should be no other declarations or preprocessor directives between
252  // comment and declaration.
253  if (Text.find_first_of(";{}#@") != StringRef::npos)
254    return nullptr;
255
256  return *Comment;
257}
258
259namespace {
260/// If we have a 'templated' declaration for a template, adjust 'D' to
261/// refer to the actual template.
262/// If we have an implicit instantiation, adjust 'D' to refer to template.
263const Decl *adjustDeclToTemplate(const Decl *D) {
264  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
265    // Is this function declaration part of a function template?
266    if (const FunctionTemplateDecl *FTD = FD->getDescribedFunctionTemplate())
267      return FTD;
268
269    // Nothing to do if function is not an implicit instantiation.
270    if (FD->getTemplateSpecializationKind() != TSK_ImplicitInstantiation)
271      return D;
272
273    // Function is an implicit instantiation of a function template?
274    if (const FunctionTemplateDecl *FTD = FD->getPrimaryTemplate())
275      return FTD;
276
277    // Function is instantiated from a member definition of a class template?
278    if (const FunctionDecl *MemberDecl =
279            FD->getInstantiatedFromMemberFunction())
280      return MemberDecl;
281
282    return D;
283  }
284  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
285    // Static data member is instantiated from a member definition of a class
286    // template?
287    if (VD->isStaticDataMember())
288      if (const VarDecl *MemberDecl = VD->getInstantiatedFromStaticDataMember())
289        return MemberDecl;
290
291    return D;
292  }
293  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(D)) {
294    // Is this class declaration part of a class template?
295    if (const ClassTemplateDecl *CTD = CRD->getDescribedClassTemplate())
296      return CTD;
297
298    // Class is an implicit instantiation of a class template or partial
299    // specialization?
300    if (const ClassTemplateSpecializationDecl *CTSD =
301            dyn_cast<ClassTemplateSpecializationDecl>(CRD)) {
302      if (CTSD->getSpecializationKind() != TSK_ImplicitInstantiation)
303        return D;
304      llvm::PointerUnion<ClassTemplateDecl *,
305                         ClassTemplatePartialSpecializationDecl *>
306          PU = CTSD->getSpecializedTemplateOrPartial();
307      return PU.is<ClassTemplateDecl*>() ?
308          static_cast<const Decl*>(PU.get<ClassTemplateDecl *>()) :
309          static_cast<const Decl*>(
310              PU.get<ClassTemplatePartialSpecializationDecl *>());
311    }
312
313    // Class is instantiated from a member definition of a class template?
314    if (const MemberSpecializationInfo *Info =
315                   CRD->getMemberSpecializationInfo())
316      return Info->getInstantiatedFrom();
317
318    return D;
319  }
320  if (const EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
321    // Enum is instantiated from a member definition of a class template?
322    if (const EnumDecl *MemberDecl = ED->getInstantiatedFromMemberEnum())
323      return MemberDecl;
324
325    return D;
326  }
327  // FIXME: Adjust alias templates?
328  return D;
329}
330} // unnamed namespace
331
332const RawComment *ASTContext::getRawCommentForAnyRedecl(
333                                                const Decl *D,
334                                                const Decl **OriginalDecl) const {
335  D = adjustDeclToTemplate(D);
336
337  // Check whether we have cached a comment for this declaration already.
338  {
339    llvm::DenseMap<const Decl *, RawCommentAndCacheFlags>::iterator Pos =
340        RedeclComments.find(D);
341    if (Pos != RedeclComments.end()) {
342      const RawCommentAndCacheFlags &Raw = Pos->second;
343      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
344        if (OriginalDecl)
345          *OriginalDecl = Raw.getOriginalDecl();
346        return Raw.getRaw();
347      }
348    }
349  }
350
351  // Search for comments attached to declarations in the redeclaration chain.
352  const RawComment *RC = nullptr;
353  const Decl *OriginalDeclForRC = nullptr;
354  for (auto I : D->redecls()) {
355    llvm::DenseMap<const Decl *, RawCommentAndCacheFlags>::iterator Pos =
356        RedeclComments.find(I);
357    if (Pos != RedeclComments.end()) {
358      const RawCommentAndCacheFlags &Raw = Pos->second;
359      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
360        RC = Raw.getRaw();
361        OriginalDeclForRC = Raw.getOriginalDecl();
362        break;
363      }
364    } else {
365      RC = getRawCommentForDeclNoCache(I);
366      OriginalDeclForRC = I;
367      RawCommentAndCacheFlags Raw;
368      if (RC) {
369        Raw.setRaw(RC);
370        Raw.setKind(RawCommentAndCacheFlags::FromDecl);
371      } else
372        Raw.setKind(RawCommentAndCacheFlags::NoCommentInDecl);
373      Raw.setOriginalDecl(I);
374      RedeclComments[I] = Raw;
375      if (RC)
376        break;
377    }
378  }
379
380  // If we found a comment, it should be a documentation comment.
381  assert(!RC || RC->isDocumentation());
382
383  if (OriginalDecl)
384    *OriginalDecl = OriginalDeclForRC;
385
386  // Update cache for every declaration in the redeclaration chain.
387  RawCommentAndCacheFlags Raw;
388  Raw.setRaw(RC);
389  Raw.setKind(RawCommentAndCacheFlags::FromRedecl);
390  Raw.setOriginalDecl(OriginalDeclForRC);
391
392  for (auto I : D->redecls()) {
393    RawCommentAndCacheFlags &R = RedeclComments[I];
394    if (R.getKind() == RawCommentAndCacheFlags::NoCommentInDecl)
395      R = Raw;
396  }
397
398  return RC;
399}
400
401static void addRedeclaredMethods(const ObjCMethodDecl *ObjCMethod,
402                   SmallVectorImpl<const NamedDecl *> &Redeclared) {
403  const DeclContext *DC = ObjCMethod->getDeclContext();
404  if (const ObjCImplDecl *IMD = dyn_cast<ObjCImplDecl>(DC)) {
405    const ObjCInterfaceDecl *ID = IMD->getClassInterface();
406    if (!ID)
407      return;
408    // Add redeclared method here.
409    for (const auto *Ext : ID->known_extensions()) {
410      if (ObjCMethodDecl *RedeclaredMethod =
411            Ext->getMethod(ObjCMethod->getSelector(),
412                                  ObjCMethod->isInstanceMethod()))
413        Redeclared.push_back(RedeclaredMethod);
414    }
415  }
416}
417
418comments::FullComment *ASTContext::cloneFullComment(comments::FullComment *FC,
419                                                    const Decl *D) const {
420  comments::DeclInfo *ThisDeclInfo = new (*this) comments::DeclInfo;
421  ThisDeclInfo->CommentDecl = D;
422  ThisDeclInfo->IsFilled = false;
423  ThisDeclInfo->fill();
424  ThisDeclInfo->CommentDecl = FC->getDecl();
425  if (!ThisDeclInfo->TemplateParameters)
426    ThisDeclInfo->TemplateParameters = FC->getDeclInfo()->TemplateParameters;
427  comments::FullComment *CFC =
428    new (*this) comments::FullComment(FC->getBlocks(),
429                                      ThisDeclInfo);
430  return CFC;
431
432}
433
434comments::FullComment *ASTContext::getLocalCommentForDeclUncached(const Decl *D) const {
435  const RawComment *RC = getRawCommentForDeclNoCache(D);
436  return RC ? RC->parse(*this, nullptr, D) : nullptr;
437}
438
439comments::FullComment *ASTContext::getCommentForDecl(
440                                              const Decl *D,
441                                              const Preprocessor *PP) const {
442  if (D->isInvalidDecl())
443    return nullptr;
444  D = adjustDeclToTemplate(D);
445
446  const Decl *Canonical = D->getCanonicalDecl();
447  llvm::DenseMap<const Decl *, comments::FullComment *>::iterator Pos =
448      ParsedComments.find(Canonical);
449
450  if (Pos != ParsedComments.end()) {
451    if (Canonical != D) {
452      comments::FullComment *FC = Pos->second;
453      comments::FullComment *CFC = cloneFullComment(FC, D);
454      return CFC;
455    }
456    return Pos->second;
457  }
458
459  const Decl *OriginalDecl;
460
461  const RawComment *RC = getRawCommentForAnyRedecl(D, &OriginalDecl);
462  if (!RC) {
463    if (isa<ObjCMethodDecl>(D) || isa<FunctionDecl>(D)) {
464      SmallVector<const NamedDecl*, 8> Overridden;
465      const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D);
466      if (OMD && OMD->isPropertyAccessor())
467        if (const ObjCPropertyDecl *PDecl = OMD->findPropertyDecl())
468          if (comments::FullComment *FC = getCommentForDecl(PDecl, PP))
469            return cloneFullComment(FC, D);
470      if (OMD)
471        addRedeclaredMethods(OMD, Overridden);
472      getOverriddenMethods(dyn_cast<NamedDecl>(D), Overridden);
473      for (unsigned i = 0, e = Overridden.size(); i < e; i++)
474        if (comments::FullComment *FC = getCommentForDecl(Overridden[i], PP))
475          return cloneFullComment(FC, D);
476    }
477    else if (const TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(D)) {
478      // Attach any tag type's documentation to its typedef if latter
479      // does not have one of its own.
480      QualType QT = TD->getUnderlyingType();
481      if (const TagType *TT = QT->getAs<TagType>())
482        if (const Decl *TD = TT->getDecl())
483          if (comments::FullComment *FC = getCommentForDecl(TD, PP))
484            return cloneFullComment(FC, D);
485    }
486    else if (const ObjCInterfaceDecl *IC = dyn_cast<ObjCInterfaceDecl>(D)) {
487      while (IC->getSuperClass()) {
488        IC = IC->getSuperClass();
489        if (comments::FullComment *FC = getCommentForDecl(IC, PP))
490          return cloneFullComment(FC, D);
491      }
492    }
493    else if (const ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(D)) {
494      if (const ObjCInterfaceDecl *IC = CD->getClassInterface())
495        if (comments::FullComment *FC = getCommentForDecl(IC, PP))
496          return cloneFullComment(FC, D);
497    }
498    else if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D)) {
499      if (!(RD = RD->getDefinition()))
500        return nullptr;
501      // Check non-virtual bases.
502      for (const auto &I : RD->bases()) {
503        if (I.isVirtual() || (I.getAccessSpecifier() != AS_public))
504          continue;
505        QualType Ty = I.getType();
506        if (Ty.isNull())
507          continue;
508        if (const CXXRecordDecl *NonVirtualBase = Ty->getAsCXXRecordDecl()) {
509          if (!(NonVirtualBase= NonVirtualBase->getDefinition()))
510            continue;
511
512          if (comments::FullComment *FC = getCommentForDecl((NonVirtualBase), PP))
513            return cloneFullComment(FC, D);
514        }
515      }
516      // Check virtual bases.
517      for (const auto &I : RD->vbases()) {
518        if (I.getAccessSpecifier() != AS_public)
519          continue;
520        QualType Ty = I.getType();
521        if (Ty.isNull())
522          continue;
523        if (const CXXRecordDecl *VirtualBase = Ty->getAsCXXRecordDecl()) {
524          if (!(VirtualBase= VirtualBase->getDefinition()))
525            continue;
526          if (comments::FullComment *FC = getCommentForDecl((VirtualBase), PP))
527            return cloneFullComment(FC, D);
528        }
529      }
530    }
531    return nullptr;
532  }
533
534  // If the RawComment was attached to other redeclaration of this Decl, we
535  // should parse the comment in context of that other Decl.  This is important
536  // because comments can contain references to parameter names which can be
537  // different across redeclarations.
538  if (D != OriginalDecl)
539    return getCommentForDecl(OriginalDecl, PP);
540
541  comments::FullComment *FC = RC->parse(*this, PP, D);
542  ParsedComments[Canonical] = FC;
543  return FC;
544}
545
546void
547ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
548                                               TemplateTemplateParmDecl *Parm) {
549  ID.AddInteger(Parm->getDepth());
550  ID.AddInteger(Parm->getPosition());
551  ID.AddBoolean(Parm->isParameterPack());
552
553  TemplateParameterList *Params = Parm->getTemplateParameters();
554  ID.AddInteger(Params->size());
555  for (TemplateParameterList::const_iterator P = Params->begin(),
556                                          PEnd = Params->end();
557       P != PEnd; ++P) {
558    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
559      ID.AddInteger(0);
560      ID.AddBoolean(TTP->isParameterPack());
561      continue;
562    }
563
564    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
565      ID.AddInteger(1);
566      ID.AddBoolean(NTTP->isParameterPack());
567      ID.AddPointer(NTTP->getType().getCanonicalType().getAsOpaquePtr());
568      if (NTTP->isExpandedParameterPack()) {
569        ID.AddBoolean(true);
570        ID.AddInteger(NTTP->getNumExpansionTypes());
571        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
572          QualType T = NTTP->getExpansionType(I);
573          ID.AddPointer(T.getCanonicalType().getAsOpaquePtr());
574        }
575      } else
576        ID.AddBoolean(false);
577      continue;
578    }
579
580    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
581    ID.AddInteger(2);
582    Profile(ID, TTP);
583  }
584}
585
586TemplateTemplateParmDecl *
587ASTContext::getCanonicalTemplateTemplateParmDecl(
588                                          TemplateTemplateParmDecl *TTP) const {
589  // Check if we already have a canonical template template parameter.
590  llvm::FoldingSetNodeID ID;
591  CanonicalTemplateTemplateParm::Profile(ID, TTP);
592  void *InsertPos = nullptr;
593  CanonicalTemplateTemplateParm *Canonical
594    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
595  if (Canonical)
596    return Canonical->getParam();
597
598  // Build a canonical template parameter list.
599  TemplateParameterList *Params = TTP->getTemplateParameters();
600  SmallVector<NamedDecl *, 4> CanonParams;
601  CanonParams.reserve(Params->size());
602  for (TemplateParameterList::const_iterator P = Params->begin(),
603                                          PEnd = Params->end();
604       P != PEnd; ++P) {
605    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
606      CanonParams.push_back(
607                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
608                                               SourceLocation(),
609                                               SourceLocation(),
610                                               TTP->getDepth(),
611                                               TTP->getIndex(), nullptr, false,
612                                               TTP->isParameterPack()));
613    else if (NonTypeTemplateParmDecl *NTTP
614             = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
615      QualType T = getCanonicalType(NTTP->getType());
616      TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
617      NonTypeTemplateParmDecl *Param;
618      if (NTTP->isExpandedParameterPack()) {
619        SmallVector<QualType, 2> ExpandedTypes;
620        SmallVector<TypeSourceInfo *, 2> ExpandedTInfos;
621        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
622          ExpandedTypes.push_back(getCanonicalType(NTTP->getExpansionType(I)));
623          ExpandedTInfos.push_back(
624                                getTrivialTypeSourceInfo(ExpandedTypes.back()));
625        }
626
627        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
628                                                SourceLocation(),
629                                                SourceLocation(),
630                                                NTTP->getDepth(),
631                                                NTTP->getPosition(), nullptr,
632                                                T,
633                                                TInfo,
634                                                ExpandedTypes.data(),
635                                                ExpandedTypes.size(),
636                                                ExpandedTInfos.data());
637      } else {
638        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
639                                                SourceLocation(),
640                                                SourceLocation(),
641                                                NTTP->getDepth(),
642                                                NTTP->getPosition(), nullptr,
643                                                T,
644                                                NTTP->isParameterPack(),
645                                                TInfo);
646      }
647      CanonParams.push_back(Param);
648
649    } else
650      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
651                                           cast<TemplateTemplateParmDecl>(*P)));
652  }
653
654  TemplateTemplateParmDecl *CanonTTP
655    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
656                                       SourceLocation(), TTP->getDepth(),
657                                       TTP->getPosition(),
658                                       TTP->isParameterPack(),
659                                       nullptr,
660                         TemplateParameterList::Create(*this, SourceLocation(),
661                                                       SourceLocation(),
662                                                       CanonParams.data(),
663                                                       CanonParams.size(),
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::GenericAArch64:
685  case TargetCXXABI::GenericMIPS:
686  case TargetCXXABI::GenericItanium:
687    return CreateItaniumCXXABI(*this);
688  case TargetCXXABI::Microsoft:
689    return CreateMicrosoftCXXABI(*this);
690  }
691  llvm_unreachable("Invalid CXXABI type!");
692}
693
694static const LangAS::Map *getAddressSpaceMap(const TargetInfo &T,
695                                             const LangOptions &LOpts) {
696  if (LOpts.FakeAddressSpaceMap) {
697    // The fake address space map must have a distinct entry for each
698    // language-specific address space.
699    static const unsigned FakeAddrSpaceMap[] = {
700      1, // opencl_global
701      2, // opencl_local
702      3, // opencl_constant
703      4, // opencl_generic
704      5, // cuda_device
705      6, // cuda_constant
706      7  // cuda_shared
707    };
708    return &FakeAddrSpaceMap;
709  } else {
710    return &T.getAddressSpaceMap();
711  }
712}
713
714static bool isAddrSpaceMapManglingEnabled(const TargetInfo &TI,
715                                          const LangOptions &LangOpts) {
716  switch (LangOpts.getAddressSpaceMapMangling()) {
717  case LangOptions::ASMM_Target:
718    return TI.useAddressSpaceMapMangling();
719  case LangOptions::ASMM_On:
720    return true;
721  case LangOptions::ASMM_Off:
722    return false;
723  }
724  llvm_unreachable("getAddressSpaceMapMangling() doesn't cover anything.");
725}
726
727ASTContext::ASTContext(LangOptions &LOpts, SourceManager &SM,
728                       IdentifierTable &idents, SelectorTable &sels,
729                       Builtin::Context &builtins)
730    : FunctionProtoTypes(this_()), TemplateSpecializationTypes(this_()),
731      DependentTemplateSpecializationTypes(this_()),
732      SubstTemplateTemplateParmPacks(this_()),
733      GlobalNestedNameSpecifier(nullptr), Int128Decl(nullptr),
734      UInt128Decl(nullptr), Float128StubDecl(nullptr),
735      BuiltinVaListDecl(nullptr), ObjCIdDecl(nullptr), ObjCSelDecl(nullptr),
736      ObjCClassDecl(nullptr), ObjCProtocolClassDecl(nullptr), BOOLDecl(nullptr),
737      CFConstantStringTypeDecl(nullptr), ObjCInstanceTypeDecl(nullptr),
738      FILEDecl(nullptr), jmp_bufDecl(nullptr), sigjmp_bufDecl(nullptr),
739      ucontext_tDecl(nullptr), BlockDescriptorType(nullptr),
740      BlockDescriptorExtendedType(nullptr), cudaConfigureCallDecl(nullptr),
741      FirstLocalImport(), LastLocalImport(), ExternCContext(nullptr),
742      SourceMgr(SM), LangOpts(LOpts),
743      SanitizerBL(new SanitizerBlacklist(LangOpts.SanitizerBlacklistFiles, SM)),
744      AddrSpaceMap(nullptr), Target(nullptr), PrintingPolicy(LOpts),
745      Idents(idents), Selectors(sels), BuiltinInfo(builtins),
746      DeclarationNames(*this), ExternalSource(nullptr), Listener(nullptr),
747      Comments(SM), CommentsLoaded(false),
748      CommentCommandTraits(BumpAlloc, LOpts.CommentOpts), LastSDM(nullptr, 0) {
749  TUDecl = TranslationUnitDecl::Create(*this);
750}
751
752ASTContext::~ASTContext() {
753  ReleaseParentMapEntries();
754
755  // Release the DenseMaps associated with DeclContext objects.
756  // FIXME: Is this the ideal solution?
757  ReleaseDeclContextMaps();
758
759  // Call all of the deallocation functions on all of their targets.
760  for (DeallocationMap::const_iterator I = Deallocations.begin(),
761           E = Deallocations.end(); I != E; ++I)
762    for (unsigned J = 0, N = I->second.size(); J != N; ++J)
763      (I->first)((I->second)[J]);
764
765  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
766  // because they can contain DenseMaps.
767  for (llvm::DenseMap<const ObjCContainerDecl*,
768       const ASTRecordLayout*>::iterator
769       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
770    // Increment in loop to prevent using deallocated memory.
771    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
772      R->Destroy(*this);
773
774  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
775       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
776    // Increment in loop to prevent using deallocated memory.
777    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
778      R->Destroy(*this);
779  }
780
781  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
782                                                    AEnd = DeclAttrs.end();
783       A != AEnd; ++A)
784    A->second->~AttrVec();
785
786  llvm::DeleteContainerSeconds(MangleNumberingContexts);
787}
788
789void ASTContext::ReleaseParentMapEntries() {
790  if (!AllParents) return;
791  for (const auto &Entry : *AllParents) {
792    if (Entry.second.is<ast_type_traits::DynTypedNode *>()) {
793      delete Entry.second.get<ast_type_traits::DynTypedNode *>();
794    } else {
795      assert(Entry.second.is<ParentVector *>());
796      delete Entry.second.get<ParentVector *>();
797    }
798  }
799}
800
801void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
802  Deallocations[Callback].push_back(Data);
803}
804
805void
806ASTContext::setExternalSource(IntrusiveRefCntPtr<ExternalASTSource> Source) {
807  ExternalSource = Source;
808}
809
810void ASTContext::PrintStats() const {
811  llvm::errs() << "\n*** AST Context Stats:\n";
812  llvm::errs() << "  " << Types.size() << " types total.\n";
813
814  unsigned counts[] = {
815#define TYPE(Name, Parent) 0,
816#define ABSTRACT_TYPE(Name, Parent)
817#include "clang/AST/TypeNodes.def"
818    0 // Extra
819  };
820
821  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
822    Type *T = Types[i];
823    counts[(unsigned)T->getTypeClass()]++;
824  }
825
826  unsigned Idx = 0;
827  unsigned TotalBytes = 0;
828#define TYPE(Name, Parent)                                              \
829  if (counts[Idx])                                                      \
830    llvm::errs() << "    " << counts[Idx] << " " << #Name               \
831                 << " types\n";                                         \
832  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
833  ++Idx;
834#define ABSTRACT_TYPE(Name, Parent)
835#include "clang/AST/TypeNodes.def"
836
837  llvm::errs() << "Total bytes = " << TotalBytes << "\n";
838
839  // Implicit special member functions.
840  llvm::errs() << NumImplicitDefaultConstructorsDeclared << "/"
841               << NumImplicitDefaultConstructors
842               << " implicit default constructors created\n";
843  llvm::errs() << NumImplicitCopyConstructorsDeclared << "/"
844               << NumImplicitCopyConstructors
845               << " implicit copy constructors created\n";
846  if (getLangOpts().CPlusPlus)
847    llvm::errs() << NumImplicitMoveConstructorsDeclared << "/"
848                 << NumImplicitMoveConstructors
849                 << " implicit move constructors created\n";
850  llvm::errs() << NumImplicitCopyAssignmentOperatorsDeclared << "/"
851               << NumImplicitCopyAssignmentOperators
852               << " implicit copy assignment operators created\n";
853  if (getLangOpts().CPlusPlus)
854    llvm::errs() << NumImplicitMoveAssignmentOperatorsDeclared << "/"
855                 << NumImplicitMoveAssignmentOperators
856                 << " implicit move assignment operators created\n";
857  llvm::errs() << NumImplicitDestructorsDeclared << "/"
858               << NumImplicitDestructors
859               << " implicit destructors created\n";
860
861  if (ExternalSource) {
862    llvm::errs() << "\n";
863    ExternalSource->PrintStats();
864  }
865
866  BumpAlloc.PrintStats();
867}
868
869ExternCContextDecl *ASTContext::getExternCContextDecl() const {
870  if (!ExternCContext)
871    ExternCContext = ExternCContextDecl::Create(*this, getTranslationUnitDecl());
872
873  return ExternCContext;
874}
875
876RecordDecl *ASTContext::buildImplicitRecord(StringRef Name,
877                                            RecordDecl::TagKind TK) const {
878  SourceLocation Loc;
879  RecordDecl *NewDecl;
880  if (getLangOpts().CPlusPlus)
881    NewDecl = CXXRecordDecl::Create(*this, TK, getTranslationUnitDecl(), Loc,
882                                    Loc, &Idents.get(Name));
883  else
884    NewDecl = RecordDecl::Create(*this, TK, getTranslationUnitDecl(), Loc, Loc,
885                                 &Idents.get(Name));
886  NewDecl->setImplicit();
887  NewDecl->addAttr(TypeVisibilityAttr::CreateImplicit(
888      const_cast<ASTContext &>(*this), TypeVisibilityAttr::Default));
889  return NewDecl;
890}
891
892TypedefDecl *ASTContext::buildImplicitTypedef(QualType T,
893                                              StringRef Name) const {
894  TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
895  TypedefDecl *NewDecl = TypedefDecl::Create(
896      const_cast<ASTContext &>(*this), getTranslationUnitDecl(),
897      SourceLocation(), SourceLocation(), &Idents.get(Name), TInfo);
898  NewDecl->setImplicit();
899  return NewDecl;
900}
901
902TypedefDecl *ASTContext::getInt128Decl() const {
903  if (!Int128Decl)
904    Int128Decl = buildImplicitTypedef(Int128Ty, "__int128_t");
905  return Int128Decl;
906}
907
908TypedefDecl *ASTContext::getUInt128Decl() const {
909  if (!UInt128Decl)
910    UInt128Decl = buildImplicitTypedef(UnsignedInt128Ty, "__uint128_t");
911  return UInt128Decl;
912}
913
914TypeDecl *ASTContext::getFloat128StubType() const {
915  assert(LangOpts.CPlusPlus && "should only be called for c++");
916  if (!Float128StubDecl)
917    Float128StubDecl = buildImplicitRecord("__float128");
918
919  return Float128StubDecl;
920}
921
922void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
923  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
924  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
925  Types.push_back(Ty);
926}
927
928void ASTContext::InitBuiltinTypes(const TargetInfo &Target) {
929  assert((!this->Target || this->Target == &Target) &&
930         "Incorrect target reinitialization");
931  assert(VoidTy.isNull() && "Context reinitialized?");
932
933  this->Target = &Target;
934
935  ABI.reset(createCXXABI(Target));
936  AddrSpaceMap = getAddressSpaceMap(Target, LangOpts);
937  AddrSpaceMapMangling = isAddrSpaceMapManglingEnabled(Target, LangOpts);
938
939  // C99 6.2.5p19.
940  InitBuiltinType(VoidTy,              BuiltinType::Void);
941
942  // C99 6.2.5p2.
943  InitBuiltinType(BoolTy,              BuiltinType::Bool);
944  // C99 6.2.5p3.
945  if (LangOpts.CharIsSigned)
946    InitBuiltinType(CharTy,            BuiltinType::Char_S);
947  else
948    InitBuiltinType(CharTy,            BuiltinType::Char_U);
949  // C99 6.2.5p4.
950  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
951  InitBuiltinType(ShortTy,             BuiltinType::Short);
952  InitBuiltinType(IntTy,               BuiltinType::Int);
953  InitBuiltinType(LongTy,              BuiltinType::Long);
954  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
955
956  // C99 6.2.5p6.
957  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
958  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
959  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
960  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
961  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
962
963  // C99 6.2.5p10.
964  InitBuiltinType(FloatTy,             BuiltinType::Float);
965  InitBuiltinType(DoubleTy,            BuiltinType::Double);
966  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
967
968  // GNU extension, 128-bit integers.
969  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
970  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
971
972  // C++ 3.9.1p5
973  if (TargetInfo::isTypeSigned(Target.getWCharType()))
974    InitBuiltinType(WCharTy,           BuiltinType::WChar_S);
975  else  // -fshort-wchar makes wchar_t be unsigned.
976    InitBuiltinType(WCharTy,           BuiltinType::WChar_U);
977  if (LangOpts.CPlusPlus && LangOpts.WChar)
978    WideCharTy = WCharTy;
979  else {
980    // C99 (or C++ using -fno-wchar).
981    WideCharTy = getFromTargetType(Target.getWCharType());
982  }
983
984  WIntTy = getFromTargetType(Target.getWIntType());
985
986  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
987    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
988  else // C99
989    Char16Ty = getFromTargetType(Target.getChar16Type());
990
991  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
992    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
993  else // C99
994    Char32Ty = getFromTargetType(Target.getChar32Type());
995
996  // Placeholder type for type-dependent expressions whose type is
997  // completely unknown. No code should ever check a type against
998  // DependentTy and users should never see it; however, it is here to
999  // help diagnose failures to properly check for type-dependent
1000  // expressions.
1001  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
1002
1003  // Placeholder type for functions.
1004  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
1005
1006  // Placeholder type for bound members.
1007  InitBuiltinType(BoundMemberTy,       BuiltinType::BoundMember);
1008
1009  // Placeholder type for pseudo-objects.
1010  InitBuiltinType(PseudoObjectTy,      BuiltinType::PseudoObject);
1011
1012  // "any" type; useful for debugger-like clients.
1013  InitBuiltinType(UnknownAnyTy,        BuiltinType::UnknownAny);
1014
1015  // Placeholder type for unbridged ARC casts.
1016  InitBuiltinType(ARCUnbridgedCastTy,  BuiltinType::ARCUnbridgedCast);
1017
1018  // Placeholder type for builtin functions.
1019  InitBuiltinType(BuiltinFnTy,  BuiltinType::BuiltinFn);
1020
1021  // C99 6.2.5p11.
1022  FloatComplexTy      = getComplexType(FloatTy);
1023  DoubleComplexTy     = getComplexType(DoubleTy);
1024  LongDoubleComplexTy = getComplexType(LongDoubleTy);
1025
1026  // Builtin types for 'id', 'Class', and 'SEL'.
1027  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
1028  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
1029  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
1030
1031  if (LangOpts.OpenCL) {
1032    InitBuiltinType(OCLImage1dTy, BuiltinType::OCLImage1d);
1033    InitBuiltinType(OCLImage1dArrayTy, BuiltinType::OCLImage1dArray);
1034    InitBuiltinType(OCLImage1dBufferTy, BuiltinType::OCLImage1dBuffer);
1035    InitBuiltinType(OCLImage2dTy, BuiltinType::OCLImage2d);
1036    InitBuiltinType(OCLImage2dArrayTy, BuiltinType::OCLImage2dArray);
1037    InitBuiltinType(OCLImage3dTy, BuiltinType::OCLImage3d);
1038
1039    InitBuiltinType(OCLSamplerTy, BuiltinType::OCLSampler);
1040    InitBuiltinType(OCLEventTy, BuiltinType::OCLEvent);
1041  }
1042
1043  // Builtin type for __objc_yes and __objc_no
1044  ObjCBuiltinBoolTy = (Target.useSignedCharForObjCBool() ?
1045                       SignedCharTy : BoolTy);
1046
1047  ObjCConstantStringType = QualType();
1048
1049  ObjCSuperType = QualType();
1050
1051  // void * type
1052  VoidPtrTy = getPointerType(VoidTy);
1053
1054  // nullptr type (C++0x 2.14.7)
1055  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
1056
1057  // half type (OpenCL 6.1.1.1) / ARM NEON __fp16
1058  InitBuiltinType(HalfTy, BuiltinType::Half);
1059
1060  // Builtin type used to help define __builtin_va_list.
1061  VaListTagTy = QualType();
1062}
1063
1064DiagnosticsEngine &ASTContext::getDiagnostics() const {
1065  return SourceMgr.getDiagnostics();
1066}
1067
1068AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
1069  AttrVec *&Result = DeclAttrs[D];
1070  if (!Result) {
1071    void *Mem = Allocate(sizeof(AttrVec));
1072    Result = new (Mem) AttrVec;
1073  }
1074
1075  return *Result;
1076}
1077
1078/// \brief Erase the attributes corresponding to the given declaration.
1079void ASTContext::eraseDeclAttrs(const Decl *D) {
1080  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
1081  if (Pos != DeclAttrs.end()) {
1082    Pos->second->~AttrVec();
1083    DeclAttrs.erase(Pos);
1084  }
1085}
1086
1087// FIXME: Remove ?
1088MemberSpecializationInfo *
1089ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
1090  assert(Var->isStaticDataMember() && "Not a static data member");
1091  return getTemplateOrSpecializationInfo(Var)
1092      .dyn_cast<MemberSpecializationInfo *>();
1093}
1094
1095ASTContext::TemplateOrSpecializationInfo
1096ASTContext::getTemplateOrSpecializationInfo(const VarDecl *Var) {
1097  llvm::DenseMap<const VarDecl *, TemplateOrSpecializationInfo>::iterator Pos =
1098      TemplateOrInstantiation.find(Var);
1099  if (Pos == TemplateOrInstantiation.end())
1100    return TemplateOrSpecializationInfo();
1101
1102  return Pos->second;
1103}
1104
1105void
1106ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
1107                                                TemplateSpecializationKind TSK,
1108                                          SourceLocation PointOfInstantiation) {
1109  assert(Inst->isStaticDataMember() && "Not a static data member");
1110  assert(Tmpl->isStaticDataMember() && "Not a static data member");
1111  setTemplateOrSpecializationInfo(Inst, new (*this) MemberSpecializationInfo(
1112                                            Tmpl, TSK, PointOfInstantiation));
1113}
1114
1115void
1116ASTContext::setTemplateOrSpecializationInfo(VarDecl *Inst,
1117                                            TemplateOrSpecializationInfo TSI) {
1118  assert(!TemplateOrInstantiation[Inst] &&
1119         "Already noted what the variable was instantiated from");
1120  TemplateOrInstantiation[Inst] = TSI;
1121}
1122
1123FunctionDecl *ASTContext::getClassScopeSpecializationPattern(
1124                                                     const FunctionDecl *FD){
1125  assert(FD && "Specialization is 0");
1126  llvm::DenseMap<const FunctionDecl*, FunctionDecl *>::const_iterator Pos
1127    = ClassScopeSpecializationPattern.find(FD);
1128  if (Pos == ClassScopeSpecializationPattern.end())
1129    return nullptr;
1130
1131  return Pos->second;
1132}
1133
1134void ASTContext::setClassScopeSpecializationPattern(FunctionDecl *FD,
1135                                        FunctionDecl *Pattern) {
1136  assert(FD && "Specialization is 0");
1137  assert(Pattern && "Class scope specialization pattern is 0");
1138  ClassScopeSpecializationPattern[FD] = Pattern;
1139}
1140
1141NamedDecl *
1142ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
1143  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
1144    = InstantiatedFromUsingDecl.find(UUD);
1145  if (Pos == InstantiatedFromUsingDecl.end())
1146    return nullptr;
1147
1148  return Pos->second;
1149}
1150
1151void
1152ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
1153  assert((isa<UsingDecl>(Pattern) ||
1154          isa<UnresolvedUsingValueDecl>(Pattern) ||
1155          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
1156         "pattern decl is not a using decl");
1157  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
1158  InstantiatedFromUsingDecl[Inst] = Pattern;
1159}
1160
1161UsingShadowDecl *
1162ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
1163  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
1164    = InstantiatedFromUsingShadowDecl.find(Inst);
1165  if (Pos == InstantiatedFromUsingShadowDecl.end())
1166    return nullptr;
1167
1168  return Pos->second;
1169}
1170
1171void
1172ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
1173                                               UsingShadowDecl *Pattern) {
1174  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
1175  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
1176}
1177
1178FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
1179  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
1180    = InstantiatedFromUnnamedFieldDecl.find(Field);
1181  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
1182    return nullptr;
1183
1184  return Pos->second;
1185}
1186
1187void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
1188                                                     FieldDecl *Tmpl) {
1189  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
1190  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
1191  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
1192         "Already noted what unnamed field was instantiated from");
1193
1194  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
1195}
1196
1197ASTContext::overridden_cxx_method_iterator
1198ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
1199  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1200    = OverriddenMethods.find(Method->getCanonicalDecl());
1201  if (Pos == OverriddenMethods.end())
1202    return nullptr;
1203
1204  return Pos->second.begin();
1205}
1206
1207ASTContext::overridden_cxx_method_iterator
1208ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
1209  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1210    = OverriddenMethods.find(Method->getCanonicalDecl());
1211  if (Pos == OverriddenMethods.end())
1212    return nullptr;
1213
1214  return Pos->second.end();
1215}
1216
1217unsigned
1218ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
1219  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1220    = OverriddenMethods.find(Method->getCanonicalDecl());
1221  if (Pos == OverriddenMethods.end())
1222    return 0;
1223
1224  return Pos->second.size();
1225}
1226
1227void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
1228                                     const CXXMethodDecl *Overridden) {
1229  assert(Method->isCanonicalDecl() && Overridden->isCanonicalDecl());
1230  OverriddenMethods[Method].push_back(Overridden);
1231}
1232
1233void ASTContext::getOverriddenMethods(
1234                      const NamedDecl *D,
1235                      SmallVectorImpl<const NamedDecl *> &Overridden) const {
1236  assert(D);
1237
1238  if (const CXXMethodDecl *CXXMethod = dyn_cast<CXXMethodDecl>(D)) {
1239    Overridden.append(overridden_methods_begin(CXXMethod),
1240                      overridden_methods_end(CXXMethod));
1241    return;
1242  }
1243
1244  const ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(D);
1245  if (!Method)
1246    return;
1247
1248  SmallVector<const ObjCMethodDecl *, 8> OverDecls;
1249  Method->getOverriddenMethods(OverDecls);
1250  Overridden.append(OverDecls.begin(), OverDecls.end());
1251}
1252
1253void ASTContext::addedLocalImportDecl(ImportDecl *Import) {
1254  assert(!Import->NextLocalImport && "Import declaration already in the chain");
1255  assert(!Import->isFromASTFile() && "Non-local import declaration");
1256  if (!FirstLocalImport) {
1257    FirstLocalImport = Import;
1258    LastLocalImport = Import;
1259    return;
1260  }
1261
1262  LastLocalImport->NextLocalImport = Import;
1263  LastLocalImport = Import;
1264}
1265
1266//===----------------------------------------------------------------------===//
1267//                         Type Sizing and Analysis
1268//===----------------------------------------------------------------------===//
1269
1270/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
1271/// scalar floating point type.
1272const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
1273  const BuiltinType *BT = T->getAs<BuiltinType>();
1274  assert(BT && "Not a floating point type!");
1275  switch (BT->getKind()) {
1276  default: llvm_unreachable("Not a floating point type!");
1277  case BuiltinType::Half:       return Target->getHalfFormat();
1278  case BuiltinType::Float:      return Target->getFloatFormat();
1279  case BuiltinType::Double:     return Target->getDoubleFormat();
1280  case BuiltinType::LongDouble: return Target->getLongDoubleFormat();
1281  }
1282}
1283
1284CharUnits ASTContext::getDeclAlign(const Decl *D, bool ForAlignof) const {
1285  unsigned Align = Target->getCharWidth();
1286
1287  bool UseAlignAttrOnly = false;
1288  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
1289    Align = AlignFromAttr;
1290
1291    // __attribute__((aligned)) can increase or decrease alignment
1292    // *except* on a struct or struct member, where it only increases
1293    // alignment unless 'packed' is also specified.
1294    //
1295    // It is an error for alignas to decrease alignment, so we can
1296    // ignore that possibility;  Sema should diagnose it.
1297    if (isa<FieldDecl>(D)) {
1298      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
1299        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1300    } else {
1301      UseAlignAttrOnly = true;
1302    }
1303  }
1304  else if (isa<FieldDecl>(D))
1305      UseAlignAttrOnly =
1306        D->hasAttr<PackedAttr>() ||
1307        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1308
1309  // If we're using the align attribute only, just ignore everything
1310  // else about the declaration and its type.
1311  if (UseAlignAttrOnly) {
1312    // do nothing
1313
1314  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
1315    QualType T = VD->getType();
1316    if (const ReferenceType *RT = T->getAs<ReferenceType>()) {
1317      if (ForAlignof)
1318        T = RT->getPointeeType();
1319      else
1320        T = getPointerType(RT->getPointeeType());
1321    }
1322    QualType BaseT = getBaseElementType(T);
1323    if (!BaseT->isIncompleteType() && !T->isFunctionType()) {
1324      // Adjust alignments of declarations with array type by the
1325      // large-array alignment on the target.
1326      if (const ArrayType *arrayType = getAsArrayType(T)) {
1327        unsigned MinWidth = Target->getLargeArrayMinWidth();
1328        if (!ForAlignof && MinWidth) {
1329          if (isa<VariableArrayType>(arrayType))
1330            Align = std::max(Align, Target->getLargeArrayAlign());
1331          else if (isa<ConstantArrayType>(arrayType) &&
1332                   MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
1333            Align = std::max(Align, Target->getLargeArrayAlign());
1334        }
1335      }
1336      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
1337      if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1338        if (VD->hasGlobalStorage())
1339          Align = std::max(Align, getTargetInfo().getMinGlobalAlign());
1340      }
1341    }
1342
1343    // Fields can be subject to extra alignment constraints, like if
1344    // the field is packed, the struct is packed, or the struct has a
1345    // a max-field-alignment constraint (#pragma pack).  So calculate
1346    // the actual alignment of the field within the struct, and then
1347    // (as we're expected to) constrain that by the alignment of the type.
1348    if (const FieldDecl *Field = dyn_cast<FieldDecl>(VD)) {
1349      const RecordDecl *Parent = Field->getParent();
1350      // We can only produce a sensible answer if the record is valid.
1351      if (!Parent->isInvalidDecl()) {
1352        const ASTRecordLayout &Layout = getASTRecordLayout(Parent);
1353
1354        // Start with the record's overall alignment.
1355        unsigned FieldAlign = toBits(Layout.getAlignment());
1356
1357        // Use the GCD of that and the offset within the record.
1358        uint64_t Offset = Layout.getFieldOffset(Field->getFieldIndex());
1359        if (Offset > 0) {
1360          // Alignment is always a power of 2, so the GCD will be a power of 2,
1361          // which means we get to do this crazy thing instead of Euclid's.
1362          uint64_t LowBitOfOffset = Offset & (~Offset + 1);
1363          if (LowBitOfOffset < FieldAlign)
1364            FieldAlign = static_cast<unsigned>(LowBitOfOffset);
1365        }
1366
1367        Align = std::min(Align, FieldAlign);
1368      }
1369    }
1370  }
1371
1372  return toCharUnitsFromBits(Align);
1373}
1374
1375// getTypeInfoDataSizeInChars - Return the size of a type, in
1376// chars. If the type is a record, its data size is returned.  This is
1377// the size of the memcpy that's performed when assigning this type
1378// using a trivial copy/move assignment operator.
1379std::pair<CharUnits, CharUnits>
1380ASTContext::getTypeInfoDataSizeInChars(QualType T) const {
1381  std::pair<CharUnits, CharUnits> sizeAndAlign = getTypeInfoInChars(T);
1382
1383  // In C++, objects can sometimes be allocated into the tail padding
1384  // of a base-class subobject.  We decide whether that's possible
1385  // during class layout, so here we can just trust the layout results.
1386  if (getLangOpts().CPlusPlus) {
1387    if (const RecordType *RT = T->getAs<RecordType>()) {
1388      const ASTRecordLayout &layout = getASTRecordLayout(RT->getDecl());
1389      sizeAndAlign.first = layout.getDataSize();
1390    }
1391  }
1392
1393  return sizeAndAlign;
1394}
1395
1396/// getConstantArrayInfoInChars - Performing the computation in CharUnits
1397/// instead of in bits prevents overflowing the uint64_t for some large arrays.
1398std::pair<CharUnits, CharUnits>
1399static getConstantArrayInfoInChars(const ASTContext &Context,
1400                                   const ConstantArrayType *CAT) {
1401  std::pair<CharUnits, CharUnits> EltInfo =
1402      Context.getTypeInfoInChars(CAT->getElementType());
1403  uint64_t Size = CAT->getSize().getZExtValue();
1404  assert((Size == 0 || static_cast<uint64_t>(EltInfo.first.getQuantity()) <=
1405              (uint64_t)(-1)/Size) &&
1406         "Overflow in array type char size evaluation");
1407  uint64_t Width = EltInfo.first.getQuantity() * Size;
1408  unsigned Align = EltInfo.second.getQuantity();
1409  if (!Context.getTargetInfo().getCXXABI().isMicrosoft() ||
1410      Context.getTargetInfo().getPointerWidth(0) == 64)
1411    Width = llvm::RoundUpToAlignment(Width, Align);
1412  return std::make_pair(CharUnits::fromQuantity(Width),
1413                        CharUnits::fromQuantity(Align));
1414}
1415
1416std::pair<CharUnits, CharUnits>
1417ASTContext::getTypeInfoInChars(const Type *T) const {
1418  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(T))
1419    return getConstantArrayInfoInChars(*this, CAT);
1420  TypeInfo Info = getTypeInfo(T);
1421  return std::make_pair(toCharUnitsFromBits(Info.Width),
1422                        toCharUnitsFromBits(Info.Align));
1423}
1424
1425std::pair<CharUnits, CharUnits>
1426ASTContext::getTypeInfoInChars(QualType T) const {
1427  return getTypeInfoInChars(T.getTypePtr());
1428}
1429
1430bool ASTContext::isAlignmentRequired(const Type *T) const {
1431  return getTypeInfo(T).AlignIsRequired;
1432}
1433
1434bool ASTContext::isAlignmentRequired(QualType T) const {
1435  return isAlignmentRequired(T.getTypePtr());
1436}
1437
1438TypeInfo ASTContext::getTypeInfo(const Type *T) const {
1439  TypeInfoMap::iterator I = MemoizedTypeInfo.find(T);
1440  if (I != MemoizedTypeInfo.end())
1441    return I->second;
1442
1443  // This call can invalidate MemoizedTypeInfo[T], so we need a second lookup.
1444  TypeInfo TI = getTypeInfoImpl(T);
1445  MemoizedTypeInfo[T] = TI;
1446  return TI;
1447}
1448
1449/// getTypeInfoImpl - Return the size of the specified type, in bits.  This
1450/// method does not work on incomplete types.
1451///
1452/// FIXME: Pointers into different addr spaces could have different sizes and
1453/// alignment requirements: getPointerInfo should take an AddrSpace, this
1454/// should take a QualType, &c.
1455TypeInfo ASTContext::getTypeInfoImpl(const Type *T) const {
1456  uint64_t Width = 0;
1457  unsigned Align = 8;
1458  bool AlignIsRequired = false;
1459  switch (T->getTypeClass()) {
1460#define TYPE(Class, Base)
1461#define ABSTRACT_TYPE(Class, Base)
1462#define NON_CANONICAL_TYPE(Class, Base)
1463#define DEPENDENT_TYPE(Class, Base) case Type::Class:
1464#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base)                       \
1465  case Type::Class:                                                            \
1466  assert(!T->isDependentType() && "should not see dependent types here");      \
1467  return getTypeInfo(cast<Class##Type>(T)->desugar().getTypePtr());
1468#include "clang/AST/TypeNodes.def"
1469    llvm_unreachable("Should not see dependent types");
1470
1471  case Type::FunctionNoProto:
1472  case Type::FunctionProto:
1473    // GCC extension: alignof(function) = 32 bits
1474    Width = 0;
1475    Align = 32;
1476    break;
1477
1478  case Type::IncompleteArray:
1479  case Type::VariableArray:
1480    Width = 0;
1481    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
1482    break;
1483
1484  case Type::ConstantArray: {
1485    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
1486
1487    TypeInfo EltInfo = getTypeInfo(CAT->getElementType());
1488    uint64_t Size = CAT->getSize().getZExtValue();
1489    assert((Size == 0 || EltInfo.Width <= (uint64_t)(-1) / Size) &&
1490           "Overflow in array type bit size evaluation");
1491    Width = EltInfo.Width * Size;
1492    Align = EltInfo.Align;
1493    if (!getTargetInfo().getCXXABI().isMicrosoft() ||
1494        getTargetInfo().getPointerWidth(0) == 64)
1495      Width = llvm::RoundUpToAlignment(Width, Align);
1496    break;
1497  }
1498  case Type::ExtVector:
1499  case Type::Vector: {
1500    const VectorType *VT = cast<VectorType>(T);
1501    TypeInfo EltInfo = getTypeInfo(VT->getElementType());
1502    Width = EltInfo.Width * VT->getNumElements();
1503    Align = Width;
1504    // If the alignment is not a power of 2, round up to the next power of 2.
1505    // This happens for non-power-of-2 length vectors.
1506    if (Align & (Align-1)) {
1507      Align = llvm::NextPowerOf2(Align);
1508      Width = llvm::RoundUpToAlignment(Width, Align);
1509    }
1510    // Adjust the alignment based on the target max.
1511    uint64_t TargetVectorAlign = Target->getMaxVectorAlign();
1512    if (TargetVectorAlign && TargetVectorAlign < Align)
1513      Align = TargetVectorAlign;
1514    break;
1515  }
1516
1517  case Type::Builtin:
1518    switch (cast<BuiltinType>(T)->getKind()) {
1519    default: llvm_unreachable("Unknown builtin type!");
1520    case BuiltinType::Void:
1521      // GCC extension: alignof(void) = 8 bits.
1522      Width = 0;
1523      Align = 8;
1524      break;
1525
1526    case BuiltinType::Bool:
1527      Width = Target->getBoolWidth();
1528      Align = Target->getBoolAlign();
1529      break;
1530    case BuiltinType::Char_S:
1531    case BuiltinType::Char_U:
1532    case BuiltinType::UChar:
1533    case BuiltinType::SChar:
1534      Width = Target->getCharWidth();
1535      Align = Target->getCharAlign();
1536      break;
1537    case BuiltinType::WChar_S:
1538    case BuiltinType::WChar_U:
1539      Width = Target->getWCharWidth();
1540      Align = Target->getWCharAlign();
1541      break;
1542    case BuiltinType::Char16:
1543      Width = Target->getChar16Width();
1544      Align = Target->getChar16Align();
1545      break;
1546    case BuiltinType::Char32:
1547      Width = Target->getChar32Width();
1548      Align = Target->getChar32Align();
1549      break;
1550    case BuiltinType::UShort:
1551    case BuiltinType::Short:
1552      Width = Target->getShortWidth();
1553      Align = Target->getShortAlign();
1554      break;
1555    case BuiltinType::UInt:
1556    case BuiltinType::Int:
1557      Width = Target->getIntWidth();
1558      Align = Target->getIntAlign();
1559      break;
1560    case BuiltinType::ULong:
1561    case BuiltinType::Long:
1562      Width = Target->getLongWidth();
1563      Align = Target->getLongAlign();
1564      break;
1565    case BuiltinType::ULongLong:
1566    case BuiltinType::LongLong:
1567      Width = Target->getLongLongWidth();
1568      Align = Target->getLongLongAlign();
1569      break;
1570    case BuiltinType::Int128:
1571    case BuiltinType::UInt128:
1572      Width = 128;
1573      Align = 128; // int128_t is 128-bit aligned on all targets.
1574      break;
1575    case BuiltinType::Half:
1576      Width = Target->getHalfWidth();
1577      Align = Target->getHalfAlign();
1578      break;
1579    case BuiltinType::Float:
1580      Width = Target->getFloatWidth();
1581      Align = Target->getFloatAlign();
1582      break;
1583    case BuiltinType::Double:
1584      Width = Target->getDoubleWidth();
1585      Align = Target->getDoubleAlign();
1586      break;
1587    case BuiltinType::LongDouble:
1588      Width = Target->getLongDoubleWidth();
1589      Align = Target->getLongDoubleAlign();
1590      break;
1591    case BuiltinType::NullPtr:
1592      Width = Target->getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
1593      Align = Target->getPointerAlign(0); //   == sizeof(void*)
1594      break;
1595    case BuiltinType::ObjCId:
1596    case BuiltinType::ObjCClass:
1597    case BuiltinType::ObjCSel:
1598      Width = Target->getPointerWidth(0);
1599      Align = Target->getPointerAlign(0);
1600      break;
1601    case BuiltinType::OCLSampler:
1602      // Samplers are modeled as integers.
1603      Width = Target->getIntWidth();
1604      Align = Target->getIntAlign();
1605      break;
1606    case BuiltinType::OCLEvent:
1607    case BuiltinType::OCLImage1d:
1608    case BuiltinType::OCLImage1dArray:
1609    case BuiltinType::OCLImage1dBuffer:
1610    case BuiltinType::OCLImage2d:
1611    case BuiltinType::OCLImage2dArray:
1612    case BuiltinType::OCLImage3d:
1613      // Currently these types are pointers to opaque types.
1614      Width = Target->getPointerWidth(0);
1615      Align = Target->getPointerAlign(0);
1616      break;
1617    }
1618    break;
1619  case Type::ObjCObjectPointer:
1620    Width = Target->getPointerWidth(0);
1621    Align = Target->getPointerAlign(0);
1622    break;
1623  case Type::BlockPointer: {
1624    unsigned AS = getTargetAddressSpace(
1625        cast<BlockPointerType>(T)->getPointeeType());
1626    Width = Target->getPointerWidth(AS);
1627    Align = Target->getPointerAlign(AS);
1628    break;
1629  }
1630  case Type::LValueReference:
1631  case Type::RValueReference: {
1632    // alignof and sizeof should never enter this code path here, so we go
1633    // the pointer route.
1634    unsigned AS = getTargetAddressSpace(
1635        cast<ReferenceType>(T)->getPointeeType());
1636    Width = Target->getPointerWidth(AS);
1637    Align = Target->getPointerAlign(AS);
1638    break;
1639  }
1640  case Type::Pointer: {
1641    unsigned AS = getTargetAddressSpace(cast<PointerType>(T)->getPointeeType());
1642    Width = Target->getPointerWidth(AS);
1643    Align = Target->getPointerAlign(AS);
1644    break;
1645  }
1646  case Type::MemberPointer: {
1647    const MemberPointerType *MPT = cast<MemberPointerType>(T);
1648    std::tie(Width, Align) = ABI->getMemberPointerWidthAndAlign(MPT);
1649    break;
1650  }
1651  case Type::Complex: {
1652    // Complex types have the same alignment as their elements, but twice the
1653    // size.
1654    TypeInfo EltInfo = getTypeInfo(cast<ComplexType>(T)->getElementType());
1655    Width = EltInfo.Width * 2;
1656    Align = EltInfo.Align;
1657    break;
1658  }
1659  case Type::ObjCObject:
1660    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
1661  case Type::Adjusted:
1662  case Type::Decayed:
1663    return getTypeInfo(cast<AdjustedType>(T)->getAdjustedType().getTypePtr());
1664  case Type::ObjCInterface: {
1665    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
1666    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
1667    Width = toBits(Layout.getSize());
1668    Align = toBits(Layout.getAlignment());
1669    break;
1670  }
1671  case Type::Record:
1672  case Type::Enum: {
1673    const TagType *TT = cast<TagType>(T);
1674
1675    if (TT->getDecl()->isInvalidDecl()) {
1676      Width = 8;
1677      Align = 8;
1678      break;
1679    }
1680
1681    if (const EnumType *ET = dyn_cast<EnumType>(TT)) {
1682      const EnumDecl *ED = ET->getDecl();
1683      TypeInfo Info =
1684          getTypeInfo(ED->getIntegerType()->getUnqualifiedDesugaredType());
1685      if (unsigned AttrAlign = ED->getMaxAlignment()) {
1686        Info.Align = AttrAlign;
1687        Info.AlignIsRequired = true;
1688      }
1689      return Info;
1690    }
1691
1692    const RecordType *RT = cast<RecordType>(TT);
1693    const RecordDecl *RD = RT->getDecl();
1694    const ASTRecordLayout &Layout = getASTRecordLayout(RD);
1695    Width = toBits(Layout.getSize());
1696    Align = toBits(Layout.getAlignment());
1697    AlignIsRequired = RD->hasAttr<AlignedAttr>();
1698    break;
1699  }
1700
1701  case Type::SubstTemplateTypeParm:
1702    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
1703                       getReplacementType().getTypePtr());
1704
1705  case Type::Auto: {
1706    const AutoType *A = cast<AutoType>(T);
1707    assert(!A->getDeducedType().isNull() &&
1708           "cannot request the size of an undeduced or dependent auto type");
1709    return getTypeInfo(A->getDeducedType().getTypePtr());
1710  }
1711
1712  case Type::Paren:
1713    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
1714
1715  case Type::Typedef: {
1716    const TypedefNameDecl *Typedef = cast<TypedefType>(T)->getDecl();
1717    TypeInfo Info = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
1718    // If the typedef has an aligned attribute on it, it overrides any computed
1719    // alignment we have.  This violates the GCC documentation (which says that
1720    // attribute(aligned) can only round up) but matches its implementation.
1721    if (unsigned AttrAlign = Typedef->getMaxAlignment()) {
1722      Align = AttrAlign;
1723      AlignIsRequired = true;
1724    } else {
1725      Align = Info.Align;
1726      AlignIsRequired = Info.AlignIsRequired;
1727    }
1728    Width = Info.Width;
1729    break;
1730  }
1731
1732  case Type::Elaborated:
1733    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
1734
1735  case Type::Attributed:
1736    return getTypeInfo(
1737                  cast<AttributedType>(T)->getEquivalentType().getTypePtr());
1738
1739  case Type::Atomic: {
1740    // Start with the base type information.
1741    TypeInfo Info = getTypeInfo(cast<AtomicType>(T)->getValueType());
1742    Width = Info.Width;
1743    Align = Info.Align;
1744
1745    // If the size of the type doesn't exceed the platform's max
1746    // atomic promotion width, make the size and alignment more
1747    // favorable to atomic operations:
1748    if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth()) {
1749      // Round the size up to a power of 2.
1750      if (!llvm::isPowerOf2_64(Width))
1751        Width = llvm::NextPowerOf2(Width);
1752
1753      // Set the alignment equal to the size.
1754      Align = static_cast<unsigned>(Width);
1755    }
1756  }
1757
1758  }
1759
1760  assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
1761  return TypeInfo(Width, Align, AlignIsRequired);
1762}
1763
1764/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1765CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1766  return CharUnits::fromQuantity(BitSize / getCharWidth());
1767}
1768
1769/// toBits - Convert a size in characters to a size in characters.
1770int64_t ASTContext::toBits(CharUnits CharSize) const {
1771  return CharSize.getQuantity() * getCharWidth();
1772}
1773
1774/// getTypeSizeInChars - Return the size of the specified type, in characters.
1775/// This method does not work on incomplete types.
1776CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1777  return getTypeInfoInChars(T).first;
1778}
1779CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1780  return getTypeInfoInChars(T).first;
1781}
1782
1783/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1784/// characters. This method does not work on incomplete types.
1785CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1786  return toCharUnitsFromBits(getTypeAlign(T));
1787}
1788CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1789  return toCharUnitsFromBits(getTypeAlign(T));
1790}
1791
1792/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1793/// type for the current target in bits.  This can be different than the ABI
1794/// alignment in cases where it is beneficial for performance to overalign
1795/// a data type.
1796unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1797  TypeInfo TI = getTypeInfo(T);
1798  unsigned ABIAlign = TI.Align;
1799
1800  if (Target->getTriple().getArch() == llvm::Triple::xcore)
1801    return ABIAlign;  // Never overalign on XCore.
1802
1803  // Double and long long should be naturally aligned if possible.
1804  T = T->getBaseElementTypeUnsafe();
1805  if (const ComplexType *CT = T->getAs<ComplexType>())
1806    T = CT->getElementType().getTypePtr();
1807  if (const EnumType *ET = T->getAs<EnumType>())
1808    T = ET->getDecl()->getIntegerType().getTypePtr();
1809  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1810      T->isSpecificBuiltinType(BuiltinType::LongLong) ||
1811      T->isSpecificBuiltinType(BuiltinType::ULongLong))
1812    // Don't increase the alignment if an alignment attribute was specified on a
1813    // typedef declaration.
1814    if (!TI.AlignIsRequired)
1815      return std::max(ABIAlign, (unsigned)getTypeSize(T));
1816
1817  return ABIAlign;
1818}
1819
1820/// getAlignOfGlobalVar - Return the alignment in bits that should be given
1821/// to a global variable of the specified type.
1822unsigned ASTContext::getAlignOfGlobalVar(QualType T) const {
1823  return std::max(getTypeAlign(T), getTargetInfo().getMinGlobalAlign());
1824}
1825
1826/// getAlignOfGlobalVarInChars - Return the alignment in characters that
1827/// should be given to a global variable of the specified type.
1828CharUnits ASTContext::getAlignOfGlobalVarInChars(QualType T) const {
1829  return toCharUnitsFromBits(getAlignOfGlobalVar(T));
1830}
1831
1832/// DeepCollectObjCIvars -
1833/// This routine first collects all declared, but not synthesized, ivars in
1834/// super class and then collects all ivars, including those synthesized for
1835/// current class. This routine is used for implementation of current class
1836/// when all ivars, declared and synthesized are known.
1837///
1838void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1839                                      bool leafClass,
1840                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1841  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1842    DeepCollectObjCIvars(SuperClass, false, Ivars);
1843  if (!leafClass) {
1844    for (const auto *I : OI->ivars())
1845      Ivars.push_back(I);
1846  } else {
1847    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1848    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1849         Iv= Iv->getNextIvar())
1850      Ivars.push_back(Iv);
1851  }
1852}
1853
1854/// CollectInheritedProtocols - Collect all protocols in current class and
1855/// those inherited by it.
1856void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1857                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1858  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1859    // We can use protocol_iterator here instead of
1860    // all_referenced_protocol_iterator since we are walking all categories.
1861    for (auto *Proto : OI->all_referenced_protocols()) {
1862      Protocols.insert(Proto->getCanonicalDecl());
1863      for (auto *P : Proto->protocols()) {
1864        Protocols.insert(P->getCanonicalDecl());
1865        CollectInheritedProtocols(P, Protocols);
1866      }
1867    }
1868
1869    // Categories of this Interface.
1870    for (const auto *Cat : OI->visible_categories())
1871      CollectInheritedProtocols(Cat, Protocols);
1872
1873    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1874      while (SD) {
1875        CollectInheritedProtocols(SD, Protocols);
1876        SD = SD->getSuperClass();
1877      }
1878  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1879    for (auto *Proto : OC->protocols()) {
1880      Protocols.insert(Proto->getCanonicalDecl());
1881      for (const auto *P : Proto->protocols())
1882        CollectInheritedProtocols(P, Protocols);
1883    }
1884  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
1885    for (auto *Proto : OP->protocols()) {
1886      Protocols.insert(Proto->getCanonicalDecl());
1887      for (const auto *P : Proto->protocols())
1888        CollectInheritedProtocols(P, Protocols);
1889    }
1890  }
1891}
1892
1893unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
1894  unsigned count = 0;
1895  // Count ivars declared in class extension.
1896  for (const auto *Ext : OI->known_extensions())
1897    count += Ext->ivar_size();
1898
1899  // Count ivar defined in this class's implementation.  This
1900  // includes synthesized ivars.
1901  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
1902    count += ImplDecl->ivar_size();
1903
1904  return count;
1905}
1906
1907bool ASTContext::isSentinelNullExpr(const Expr *E) {
1908  if (!E)
1909    return false;
1910
1911  // nullptr_t is always treated as null.
1912  if (E->getType()->isNullPtrType()) return true;
1913
1914  if (E->getType()->isAnyPointerType() &&
1915      E->IgnoreParenCasts()->isNullPointerConstant(*this,
1916                                                Expr::NPC_ValueDependentIsNull))
1917    return true;
1918
1919  // Unfortunately, __null has type 'int'.
1920  if (isa<GNUNullExpr>(E)) return true;
1921
1922  return false;
1923}
1924
1925/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
1926ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
1927  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1928    I = ObjCImpls.find(D);
1929  if (I != ObjCImpls.end())
1930    return cast<ObjCImplementationDecl>(I->second);
1931  return nullptr;
1932}
1933/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
1934ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
1935  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1936    I = ObjCImpls.find(D);
1937  if (I != ObjCImpls.end())
1938    return cast<ObjCCategoryImplDecl>(I->second);
1939  return nullptr;
1940}
1941
1942/// \brief Set the implementation of ObjCInterfaceDecl.
1943void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1944                           ObjCImplementationDecl *ImplD) {
1945  assert(IFaceD && ImplD && "Passed null params");
1946  ObjCImpls[IFaceD] = ImplD;
1947}
1948/// \brief Set the implementation of ObjCCategoryDecl.
1949void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1950                           ObjCCategoryImplDecl *ImplD) {
1951  assert(CatD && ImplD && "Passed null params");
1952  ObjCImpls[CatD] = ImplD;
1953}
1954
1955const ObjCInterfaceDecl *ASTContext::getObjContainingInterface(
1956                                              const NamedDecl *ND) const {
1957  if (const ObjCInterfaceDecl *ID =
1958          dyn_cast<ObjCInterfaceDecl>(ND->getDeclContext()))
1959    return ID;
1960  if (const ObjCCategoryDecl *CD =
1961          dyn_cast<ObjCCategoryDecl>(ND->getDeclContext()))
1962    return CD->getClassInterface();
1963  if (const ObjCImplDecl *IMD =
1964          dyn_cast<ObjCImplDecl>(ND->getDeclContext()))
1965    return IMD->getClassInterface();
1966
1967  return nullptr;
1968}
1969
1970/// \brief Get the copy initialization expression of VarDecl,or NULL if
1971/// none exists.
1972Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
1973  assert(VD && "Passed null params");
1974  assert(VD->hasAttr<BlocksAttr>() &&
1975         "getBlockVarCopyInits - not __block var");
1976  llvm::DenseMap<const VarDecl*, Expr*>::iterator
1977    I = BlockVarCopyInits.find(VD);
1978  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : nullptr;
1979}
1980
1981/// \brief Set the copy inialization expression of a block var decl.
1982void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
1983  assert(VD && Init && "Passed null params");
1984  assert(VD->hasAttr<BlocksAttr>() &&
1985         "setBlockVarCopyInits - not __block var");
1986  BlockVarCopyInits[VD] = Init;
1987}
1988
1989TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1990                                                 unsigned DataSize) const {
1991  if (!DataSize)
1992    DataSize = TypeLoc::getFullDataSizeForType(T);
1993  else
1994    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1995           "incorrect data size provided to CreateTypeSourceInfo!");
1996
1997  TypeSourceInfo *TInfo =
1998    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1999  new (TInfo) TypeSourceInfo(T);
2000  return TInfo;
2001}
2002
2003TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
2004                                                     SourceLocation L) const {
2005  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
2006  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
2007  return DI;
2008}
2009
2010const ASTRecordLayout &
2011ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
2012  return getObjCLayout(D, nullptr);
2013}
2014
2015const ASTRecordLayout &
2016ASTContext::getASTObjCImplementationLayout(
2017                                        const ObjCImplementationDecl *D) const {
2018  return getObjCLayout(D->getClassInterface(), D);
2019}
2020
2021//===----------------------------------------------------------------------===//
2022//                   Type creation/memoization methods
2023//===----------------------------------------------------------------------===//
2024
2025QualType
2026ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
2027  unsigned fastQuals = quals.getFastQualifiers();
2028  quals.removeFastQualifiers();
2029
2030  // Check if we've already instantiated this type.
2031  llvm::FoldingSetNodeID ID;
2032  ExtQuals::Profile(ID, baseType, quals);
2033  void *insertPos = nullptr;
2034  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
2035    assert(eq->getQualifiers() == quals);
2036    return QualType(eq, fastQuals);
2037  }
2038
2039  // If the base type is not canonical, make the appropriate canonical type.
2040  QualType canon;
2041  if (!baseType->isCanonicalUnqualified()) {
2042    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
2043    canonSplit.Quals.addConsistentQualifiers(quals);
2044    canon = getExtQualType(canonSplit.Ty, canonSplit.Quals);
2045
2046    // Re-find the insert position.
2047    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
2048  }
2049
2050  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
2051  ExtQualNodes.InsertNode(eq, insertPos);
2052  return QualType(eq, fastQuals);
2053}
2054
2055QualType
2056ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
2057  QualType CanT = getCanonicalType(T);
2058  if (CanT.getAddressSpace() == AddressSpace)
2059    return T;
2060
2061  // If we are composing extended qualifiers together, merge together
2062  // into one ExtQuals node.
2063  QualifierCollector Quals;
2064  const Type *TypeNode = Quals.strip(T);
2065
2066  // If this type already has an address space specified, it cannot get
2067  // another one.
2068  assert(!Quals.hasAddressSpace() &&
2069         "Type cannot be in multiple addr spaces!");
2070  Quals.addAddressSpace(AddressSpace);
2071
2072  return getExtQualType(TypeNode, Quals);
2073}
2074
2075QualType ASTContext::getObjCGCQualType(QualType T,
2076                                       Qualifiers::GC GCAttr) const {
2077  QualType CanT = getCanonicalType(T);
2078  if (CanT.getObjCGCAttr() == GCAttr)
2079    return T;
2080
2081  if (const PointerType *ptr = T->getAs<PointerType>()) {
2082    QualType Pointee = ptr->getPointeeType();
2083    if (Pointee->isAnyPointerType()) {
2084      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
2085      return getPointerType(ResultType);
2086    }
2087  }
2088
2089  // If we are composing extended qualifiers together, merge together
2090  // into one ExtQuals node.
2091  QualifierCollector Quals;
2092  const Type *TypeNode = Quals.strip(T);
2093
2094  // If this type already has an ObjCGC specified, it cannot get
2095  // another one.
2096  assert(!Quals.hasObjCGCAttr() &&
2097         "Type cannot have multiple ObjCGCs!");
2098  Quals.addObjCGCAttr(GCAttr);
2099
2100  return getExtQualType(TypeNode, Quals);
2101}
2102
2103const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
2104                                                   FunctionType::ExtInfo Info) {
2105  if (T->getExtInfo() == Info)
2106    return T;
2107
2108  QualType Result;
2109  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
2110    Result = getFunctionNoProtoType(FNPT->getReturnType(), Info);
2111  } else {
2112    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
2113    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
2114    EPI.ExtInfo = Info;
2115    Result = getFunctionType(FPT->getReturnType(), FPT->getParamTypes(), EPI);
2116  }
2117
2118  return cast<FunctionType>(Result.getTypePtr());
2119}
2120
2121void ASTContext::adjustDeducedFunctionResultType(FunctionDecl *FD,
2122                                                 QualType ResultType) {
2123  FD = FD->getMostRecentDecl();
2124  while (true) {
2125    const FunctionProtoType *FPT = FD->getType()->castAs<FunctionProtoType>();
2126    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
2127    FD->setType(getFunctionType(ResultType, FPT->getParamTypes(), EPI));
2128    if (FunctionDecl *Next = FD->getPreviousDecl())
2129      FD = Next;
2130    else
2131      break;
2132  }
2133  if (ASTMutationListener *L = getASTMutationListener())
2134    L->DeducedReturnType(FD, ResultType);
2135}
2136
2137/// Get a function type and produce the equivalent function type with the
2138/// specified exception specification. Type sugar that can be present on a
2139/// declaration of a function with an exception specification is permitted
2140/// and preserved. Other type sugar (for instance, typedefs) is not.
2141static QualType getFunctionTypeWithExceptionSpec(
2142    ASTContext &Context, QualType Orig,
2143    const FunctionProtoType::ExceptionSpecInfo &ESI) {
2144  // Might have some parens.
2145  if (auto *PT = dyn_cast<ParenType>(Orig))
2146    return Context.getParenType(
2147        getFunctionTypeWithExceptionSpec(Context, PT->getInnerType(), ESI));
2148
2149  // Might have a calling-convention attribute.
2150  if (auto *AT = dyn_cast<AttributedType>(Orig))
2151    return Context.getAttributedType(
2152        AT->getAttrKind(),
2153        getFunctionTypeWithExceptionSpec(Context, AT->getModifiedType(), ESI),
2154        getFunctionTypeWithExceptionSpec(Context, AT->getEquivalentType(),
2155                                         ESI));
2156
2157  // Anything else must be a function type. Rebuild it with the new exception
2158  // specification.
2159  const FunctionProtoType *Proto = cast<FunctionProtoType>(Orig);
2160  return Context.getFunctionType(
2161      Proto->getReturnType(), Proto->getParamTypes(),
2162      Proto->getExtProtoInfo().withExceptionSpec(ESI));
2163}
2164
2165void ASTContext::adjustExceptionSpec(
2166    FunctionDecl *FD, const FunctionProtoType::ExceptionSpecInfo &ESI,
2167    bool AsWritten) {
2168  // Update the type.
2169  QualType Updated =
2170      getFunctionTypeWithExceptionSpec(*this, FD->getType(), ESI);
2171  FD->setType(Updated);
2172
2173  if (!AsWritten)
2174    return;
2175
2176  // Update the type in the type source information too.
2177  if (TypeSourceInfo *TSInfo = FD->getTypeSourceInfo()) {
2178    // If the type and the type-as-written differ, we may need to update
2179    // the type-as-written too.
2180    if (TSInfo->getType() != FD->getType())
2181      Updated = getFunctionTypeWithExceptionSpec(*this, TSInfo->getType(), ESI);
2182
2183    // FIXME: When we get proper type location information for exceptions,
2184    // we'll also have to rebuild the TypeSourceInfo. For now, we just patch
2185    // up the TypeSourceInfo;
2186    assert(TypeLoc::getFullDataSizeForType(Updated) ==
2187               TypeLoc::getFullDataSizeForType(TSInfo->getType()) &&
2188           "TypeLoc size mismatch from updating exception specification");
2189    TSInfo->overrideType(Updated);
2190  }
2191}
2192
2193/// getComplexType - Return the uniqued reference to the type for a complex
2194/// number with the specified element type.
2195QualType ASTContext::getComplexType(QualType T) const {
2196  // Unique pointers, to guarantee there is only one pointer of a particular
2197  // structure.
2198  llvm::FoldingSetNodeID ID;
2199  ComplexType::Profile(ID, T);
2200
2201  void *InsertPos = nullptr;
2202  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
2203    return QualType(CT, 0);
2204
2205  // If the pointee type isn't canonical, this won't be a canonical type either,
2206  // so fill in the canonical type field.
2207  QualType Canonical;
2208  if (!T.isCanonical()) {
2209    Canonical = getComplexType(getCanonicalType(T));
2210
2211    // Get the new insert position for the node we care about.
2212    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
2213    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2214  }
2215  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
2216  Types.push_back(New);
2217  ComplexTypes.InsertNode(New, InsertPos);
2218  return QualType(New, 0);
2219}
2220
2221/// getPointerType - Return the uniqued reference to the type for a pointer to
2222/// the specified type.
2223QualType ASTContext::getPointerType(QualType T) const {
2224  // Unique pointers, to guarantee there is only one pointer of a particular
2225  // structure.
2226  llvm::FoldingSetNodeID ID;
2227  PointerType::Profile(ID, T);
2228
2229  void *InsertPos = nullptr;
2230  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2231    return QualType(PT, 0);
2232
2233  // If the pointee type isn't canonical, this won't be a canonical type either,
2234  // so fill in the canonical type field.
2235  QualType Canonical;
2236  if (!T.isCanonical()) {
2237    Canonical = getPointerType(getCanonicalType(T));
2238
2239    // Get the new insert position for the node we care about.
2240    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2241    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2242  }
2243  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
2244  Types.push_back(New);
2245  PointerTypes.InsertNode(New, InsertPos);
2246  return QualType(New, 0);
2247}
2248
2249QualType ASTContext::getAdjustedType(QualType Orig, QualType New) const {
2250  llvm::FoldingSetNodeID ID;
2251  AdjustedType::Profile(ID, Orig, New);
2252  void *InsertPos = nullptr;
2253  AdjustedType *AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
2254  if (AT)
2255    return QualType(AT, 0);
2256
2257  QualType Canonical = getCanonicalType(New);
2258
2259  // Get the new insert position for the node we care about.
2260  AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
2261  assert(!AT && "Shouldn't be in the map!");
2262
2263  AT = new (*this, TypeAlignment)
2264      AdjustedType(Type::Adjusted, Orig, New, Canonical);
2265  Types.push_back(AT);
2266  AdjustedTypes.InsertNode(AT, InsertPos);
2267  return QualType(AT, 0);
2268}
2269
2270QualType ASTContext::getDecayedType(QualType T) const {
2271  assert((T->isArrayType() || T->isFunctionType()) && "T does not decay");
2272
2273  QualType Decayed;
2274
2275  // C99 6.7.5.3p7:
2276  //   A declaration of a parameter as "array of type" shall be
2277  //   adjusted to "qualified pointer to type", where the type
2278  //   qualifiers (if any) are those specified within the [ and ] of
2279  //   the array type derivation.
2280  if (T->isArrayType())
2281    Decayed = getArrayDecayedType(T);
2282
2283  // C99 6.7.5.3p8:
2284  //   A declaration of a parameter as "function returning type"
2285  //   shall be adjusted to "pointer to function returning type", as
2286  //   in 6.3.2.1.
2287  if (T->isFunctionType())
2288    Decayed = getPointerType(T);
2289
2290  llvm::FoldingSetNodeID ID;
2291  AdjustedType::Profile(ID, T, Decayed);
2292  void *InsertPos = nullptr;
2293  AdjustedType *AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
2294  if (AT)
2295    return QualType(AT, 0);
2296
2297  QualType Canonical = getCanonicalType(Decayed);
2298
2299  // Get the new insert position for the node we care about.
2300  AT = AdjustedTypes.FindNodeOrInsertPos(ID, InsertPos);
2301  assert(!AT && "Shouldn't be in the map!");
2302
2303  AT = new (*this, TypeAlignment) DecayedType(T, Decayed, Canonical);
2304  Types.push_back(AT);
2305  AdjustedTypes.InsertNode(AT, InsertPos);
2306  return QualType(AT, 0);
2307}
2308
2309/// getBlockPointerType - Return the uniqued reference to the type for
2310/// a pointer to the specified block.
2311QualType ASTContext::getBlockPointerType(QualType T) const {
2312  assert(T->isFunctionType() && "block of function types only");
2313  // Unique pointers, to guarantee there is only one block of a particular
2314  // structure.
2315  llvm::FoldingSetNodeID ID;
2316  BlockPointerType::Profile(ID, T);
2317
2318  void *InsertPos = nullptr;
2319  if (BlockPointerType *PT =
2320        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2321    return QualType(PT, 0);
2322
2323  // If the block pointee type isn't canonical, this won't be a canonical
2324  // type either so fill in the canonical type field.
2325  QualType Canonical;
2326  if (!T.isCanonical()) {
2327    Canonical = getBlockPointerType(getCanonicalType(T));
2328
2329    // Get the new insert position for the node we care about.
2330    BlockPointerType *NewIP =
2331      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2332    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2333  }
2334  BlockPointerType *New
2335    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
2336  Types.push_back(New);
2337  BlockPointerTypes.InsertNode(New, InsertPos);
2338  return QualType(New, 0);
2339}
2340
2341/// getLValueReferenceType - Return the uniqued reference to the type for an
2342/// lvalue reference to the specified type.
2343QualType
2344ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
2345  assert(getCanonicalType(T) != OverloadTy &&
2346         "Unresolved overloaded function type");
2347
2348  // Unique pointers, to guarantee there is only one pointer of a particular
2349  // structure.
2350  llvm::FoldingSetNodeID ID;
2351  ReferenceType::Profile(ID, T, SpelledAsLValue);
2352
2353  void *InsertPos = nullptr;
2354  if (LValueReferenceType *RT =
2355        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
2356    return QualType(RT, 0);
2357
2358  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
2359
2360  // If the referencee type isn't canonical, this won't be a canonical type
2361  // either, so fill in the canonical type field.
2362  QualType Canonical;
2363  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
2364    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
2365    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
2366
2367    // Get the new insert position for the node we care about.
2368    LValueReferenceType *NewIP =
2369      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
2370    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2371  }
2372
2373  LValueReferenceType *New
2374    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
2375                                                     SpelledAsLValue);
2376  Types.push_back(New);
2377  LValueReferenceTypes.InsertNode(New, InsertPos);
2378
2379  return QualType(New, 0);
2380}
2381
2382/// getRValueReferenceType - Return the uniqued reference to the type for an
2383/// rvalue reference to the specified type.
2384QualType ASTContext::getRValueReferenceType(QualType T) const {
2385  // Unique pointers, to guarantee there is only one pointer of a particular
2386  // structure.
2387  llvm::FoldingSetNodeID ID;
2388  ReferenceType::Profile(ID, T, false);
2389
2390  void *InsertPos = nullptr;
2391  if (RValueReferenceType *RT =
2392        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
2393    return QualType(RT, 0);
2394
2395  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
2396
2397  // If the referencee type isn't canonical, this won't be a canonical type
2398  // either, so fill in the canonical type field.
2399  QualType Canonical;
2400  if (InnerRef || !T.isCanonical()) {
2401    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
2402    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
2403
2404    // Get the new insert position for the node we care about.
2405    RValueReferenceType *NewIP =
2406      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
2407    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2408  }
2409
2410  RValueReferenceType *New
2411    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
2412  Types.push_back(New);
2413  RValueReferenceTypes.InsertNode(New, InsertPos);
2414  return QualType(New, 0);
2415}
2416
2417/// getMemberPointerType - Return the uniqued reference to the type for a
2418/// member pointer to the specified type, in the specified class.
2419QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
2420  // Unique pointers, to guarantee there is only one pointer of a particular
2421  // structure.
2422  llvm::FoldingSetNodeID ID;
2423  MemberPointerType::Profile(ID, T, Cls);
2424
2425  void *InsertPos = nullptr;
2426  if (MemberPointerType *PT =
2427      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2428    return QualType(PT, 0);
2429
2430  // If the pointee or class type isn't canonical, this won't be a canonical
2431  // type either, so fill in the canonical type field.
2432  QualType Canonical;
2433  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
2434    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
2435
2436    // Get the new insert position for the node we care about.
2437    MemberPointerType *NewIP =
2438      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2439    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2440  }
2441  MemberPointerType *New
2442    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
2443  Types.push_back(New);
2444  MemberPointerTypes.InsertNode(New, InsertPos);
2445  return QualType(New, 0);
2446}
2447
2448/// getConstantArrayType - Return the unique reference to the type for an
2449/// array of the specified element type.
2450QualType ASTContext::getConstantArrayType(QualType EltTy,
2451                                          const llvm::APInt &ArySizeIn,
2452                                          ArrayType::ArraySizeModifier ASM,
2453                                          unsigned IndexTypeQuals) const {
2454  assert((EltTy->isDependentType() ||
2455          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
2456         "Constant array of VLAs is illegal!");
2457
2458  // Convert the array size into a canonical width matching the pointer size for
2459  // the target.
2460  llvm::APInt ArySize(ArySizeIn);
2461  ArySize =
2462    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
2463
2464  llvm::FoldingSetNodeID ID;
2465  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
2466
2467  void *InsertPos = nullptr;
2468  if (ConstantArrayType *ATP =
2469      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
2470    return QualType(ATP, 0);
2471
2472  // If the element type isn't canonical or has qualifiers, this won't
2473  // be a canonical type either, so fill in the canonical type field.
2474  QualType Canon;
2475  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2476    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2477    Canon = getConstantArrayType(QualType(canonSplit.Ty, 0), ArySize,
2478                                 ASM, IndexTypeQuals);
2479    Canon = getQualifiedType(Canon, canonSplit.Quals);
2480
2481    // Get the new insert position for the node we care about.
2482    ConstantArrayType *NewIP =
2483      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
2484    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2485  }
2486
2487  ConstantArrayType *New = new(*this,TypeAlignment)
2488    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
2489  ConstantArrayTypes.InsertNode(New, InsertPos);
2490  Types.push_back(New);
2491  return QualType(New, 0);
2492}
2493
2494/// getVariableArrayDecayedType - Turns the given type, which may be
2495/// variably-modified, into the corresponding type with all the known
2496/// sizes replaced with [*].
2497QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
2498  // Vastly most common case.
2499  if (!type->isVariablyModifiedType()) return type;
2500
2501  QualType result;
2502
2503  SplitQualType split = type.getSplitDesugaredType();
2504  const Type *ty = split.Ty;
2505  switch (ty->getTypeClass()) {
2506#define TYPE(Class, Base)
2507#define ABSTRACT_TYPE(Class, Base)
2508#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
2509#include "clang/AST/TypeNodes.def"
2510    llvm_unreachable("didn't desugar past all non-canonical types?");
2511
2512  // These types should never be variably-modified.
2513  case Type::Builtin:
2514  case Type::Complex:
2515  case Type::Vector:
2516  case Type::ExtVector:
2517  case Type::DependentSizedExtVector:
2518  case Type::ObjCObject:
2519  case Type::ObjCInterface:
2520  case Type::ObjCObjectPointer:
2521  case Type::Record:
2522  case Type::Enum:
2523  case Type::UnresolvedUsing:
2524  case Type::TypeOfExpr:
2525  case Type::TypeOf:
2526  case Type::Decltype:
2527  case Type::UnaryTransform:
2528  case Type::DependentName:
2529  case Type::InjectedClassName:
2530  case Type::TemplateSpecialization:
2531  case Type::DependentTemplateSpecialization:
2532  case Type::TemplateTypeParm:
2533  case Type::SubstTemplateTypeParmPack:
2534  case Type::Auto:
2535  case Type::PackExpansion:
2536    llvm_unreachable("type should never be variably-modified");
2537
2538  // These types can be variably-modified but should never need to
2539  // further decay.
2540  case Type::FunctionNoProto:
2541  case Type::FunctionProto:
2542  case Type::BlockPointer:
2543  case Type::MemberPointer:
2544    return type;
2545
2546  // These types can be variably-modified.  All these modifications
2547  // preserve structure except as noted by comments.
2548  // TODO: if we ever care about optimizing VLAs, there are no-op
2549  // optimizations available here.
2550  case Type::Pointer:
2551    result = getPointerType(getVariableArrayDecayedType(
2552                              cast<PointerType>(ty)->getPointeeType()));
2553    break;
2554
2555  case Type::LValueReference: {
2556    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
2557    result = getLValueReferenceType(
2558                 getVariableArrayDecayedType(lv->getPointeeType()),
2559                                    lv->isSpelledAsLValue());
2560    break;
2561  }
2562
2563  case Type::RValueReference: {
2564    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
2565    result = getRValueReferenceType(
2566                 getVariableArrayDecayedType(lv->getPointeeType()));
2567    break;
2568  }
2569
2570  case Type::Atomic: {
2571    const AtomicType *at = cast<AtomicType>(ty);
2572    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
2573    break;
2574  }
2575
2576  case Type::ConstantArray: {
2577    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
2578    result = getConstantArrayType(
2579                 getVariableArrayDecayedType(cat->getElementType()),
2580                                  cat->getSize(),
2581                                  cat->getSizeModifier(),
2582                                  cat->getIndexTypeCVRQualifiers());
2583    break;
2584  }
2585
2586  case Type::DependentSizedArray: {
2587    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
2588    result = getDependentSizedArrayType(
2589                 getVariableArrayDecayedType(dat->getElementType()),
2590                                        dat->getSizeExpr(),
2591                                        dat->getSizeModifier(),
2592                                        dat->getIndexTypeCVRQualifiers(),
2593                                        dat->getBracketsRange());
2594    break;
2595  }
2596
2597  // Turn incomplete types into [*] types.
2598  case Type::IncompleteArray: {
2599    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
2600    result = getVariableArrayType(
2601                 getVariableArrayDecayedType(iat->getElementType()),
2602                                  /*size*/ nullptr,
2603                                  ArrayType::Normal,
2604                                  iat->getIndexTypeCVRQualifiers(),
2605                                  SourceRange());
2606    break;
2607  }
2608
2609  // Turn VLA types into [*] types.
2610  case Type::VariableArray: {
2611    const VariableArrayType *vat = cast<VariableArrayType>(ty);
2612    result = getVariableArrayType(
2613                 getVariableArrayDecayedType(vat->getElementType()),
2614                                  /*size*/ nullptr,
2615                                  ArrayType::Star,
2616                                  vat->getIndexTypeCVRQualifiers(),
2617                                  vat->getBracketsRange());
2618    break;
2619  }
2620  }
2621
2622  // Apply the top-level qualifiers from the original.
2623  return getQualifiedType(result, split.Quals);
2624}
2625
2626/// getVariableArrayType - Returns a non-unique reference to the type for a
2627/// variable array of the specified element type.
2628QualType ASTContext::getVariableArrayType(QualType EltTy,
2629                                          Expr *NumElts,
2630                                          ArrayType::ArraySizeModifier ASM,
2631                                          unsigned IndexTypeQuals,
2632                                          SourceRange Brackets) const {
2633  // Since we don't unique expressions, it isn't possible to unique VLA's
2634  // that have an expression provided for their size.
2635  QualType Canon;
2636
2637  // Be sure to pull qualifiers off the element type.
2638  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2639    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2640    Canon = getVariableArrayType(QualType(canonSplit.Ty, 0), NumElts, ASM,
2641                                 IndexTypeQuals, Brackets);
2642    Canon = getQualifiedType(Canon, canonSplit.Quals);
2643  }
2644
2645  VariableArrayType *New = new(*this, TypeAlignment)
2646    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
2647
2648  VariableArrayTypes.push_back(New);
2649  Types.push_back(New);
2650  return QualType(New, 0);
2651}
2652
2653/// getDependentSizedArrayType - Returns a non-unique reference to
2654/// the type for a dependently-sized array of the specified element
2655/// type.
2656QualType ASTContext::getDependentSizedArrayType(QualType elementType,
2657                                                Expr *numElements,
2658                                                ArrayType::ArraySizeModifier ASM,
2659                                                unsigned elementTypeQuals,
2660                                                SourceRange brackets) const {
2661  assert((!numElements || numElements->isTypeDependent() ||
2662          numElements->isValueDependent()) &&
2663         "Size must be type- or value-dependent!");
2664
2665  // Dependently-sized array types that do not have a specified number
2666  // of elements will have their sizes deduced from a dependent
2667  // initializer.  We do no canonicalization here at all, which is okay
2668  // because they can't be used in most locations.
2669  if (!numElements) {
2670    DependentSizedArrayType *newType
2671      = new (*this, TypeAlignment)
2672          DependentSizedArrayType(*this, elementType, QualType(),
2673                                  numElements, ASM, elementTypeQuals,
2674                                  brackets);
2675    Types.push_back(newType);
2676    return QualType(newType, 0);
2677  }
2678
2679  // Otherwise, we actually build a new type every time, but we
2680  // also build a canonical type.
2681
2682  SplitQualType canonElementType = getCanonicalType(elementType).split();
2683
2684  void *insertPos = nullptr;
2685  llvm::FoldingSetNodeID ID;
2686  DependentSizedArrayType::Profile(ID, *this,
2687                                   QualType(canonElementType.Ty, 0),
2688                                   ASM, elementTypeQuals, numElements);
2689
2690  // Look for an existing type with these properties.
2691  DependentSizedArrayType *canonTy =
2692    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2693
2694  // If we don't have one, build one.
2695  if (!canonTy) {
2696    canonTy = new (*this, TypeAlignment)
2697      DependentSizedArrayType(*this, QualType(canonElementType.Ty, 0),
2698                              QualType(), numElements, ASM, elementTypeQuals,
2699                              brackets);
2700    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
2701    Types.push_back(canonTy);
2702  }
2703
2704  // Apply qualifiers from the element type to the array.
2705  QualType canon = getQualifiedType(QualType(canonTy,0),
2706                                    canonElementType.Quals);
2707
2708  // If we didn't need extra canonicalization for the element type,
2709  // then just use that as our result.
2710  if (QualType(canonElementType.Ty, 0) == elementType)
2711    return canon;
2712
2713  // Otherwise, we need to build a type which follows the spelling
2714  // of the element type.
2715  DependentSizedArrayType *sugaredType
2716    = new (*this, TypeAlignment)
2717        DependentSizedArrayType(*this, elementType, canon, numElements,
2718                                ASM, elementTypeQuals, brackets);
2719  Types.push_back(sugaredType);
2720  return QualType(sugaredType, 0);
2721}
2722
2723QualType ASTContext::getIncompleteArrayType(QualType elementType,
2724                                            ArrayType::ArraySizeModifier ASM,
2725                                            unsigned elementTypeQuals) const {
2726  llvm::FoldingSetNodeID ID;
2727  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
2728
2729  void *insertPos = nullptr;
2730  if (IncompleteArrayType *iat =
2731       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
2732    return QualType(iat, 0);
2733
2734  // If the element type isn't canonical, this won't be a canonical type
2735  // either, so fill in the canonical type field.  We also have to pull
2736  // qualifiers off the element type.
2737  QualType canon;
2738
2739  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
2740    SplitQualType canonSplit = getCanonicalType(elementType).split();
2741    canon = getIncompleteArrayType(QualType(canonSplit.Ty, 0),
2742                                   ASM, elementTypeQuals);
2743    canon = getQualifiedType(canon, canonSplit.Quals);
2744
2745    // Get the new insert position for the node we care about.
2746    IncompleteArrayType *existing =
2747      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2748    assert(!existing && "Shouldn't be in the map!"); (void) existing;
2749  }
2750
2751  IncompleteArrayType *newType = new (*this, TypeAlignment)
2752    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
2753
2754  IncompleteArrayTypes.InsertNode(newType, insertPos);
2755  Types.push_back(newType);
2756  return QualType(newType, 0);
2757}
2758
2759/// getVectorType - Return the unique reference to a vector type of
2760/// the specified element type and size. VectorType must be a built-in type.
2761QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
2762                                   VectorType::VectorKind VecKind) const {
2763  assert(vecType->isBuiltinType());
2764
2765  // Check if we've already instantiated a vector of this type.
2766  llvm::FoldingSetNodeID ID;
2767  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
2768
2769  void *InsertPos = nullptr;
2770  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2771    return QualType(VTP, 0);
2772
2773  // If the element type isn't canonical, this won't be a canonical type either,
2774  // so fill in the canonical type field.
2775  QualType Canonical;
2776  if (!vecType.isCanonical()) {
2777    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
2778
2779    // Get the new insert position for the node we care about.
2780    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2781    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2782  }
2783  VectorType *New = new (*this, TypeAlignment)
2784    VectorType(vecType, NumElts, Canonical, VecKind);
2785  VectorTypes.InsertNode(New, InsertPos);
2786  Types.push_back(New);
2787  return QualType(New, 0);
2788}
2789
2790/// getExtVectorType - Return the unique reference to an extended vector type of
2791/// the specified element type and size. VectorType must be a built-in type.
2792QualType
2793ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
2794  assert(vecType->isBuiltinType() || vecType->isDependentType());
2795
2796  // Check if we've already instantiated a vector of this type.
2797  llvm::FoldingSetNodeID ID;
2798  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
2799                      VectorType::GenericVector);
2800  void *InsertPos = nullptr;
2801  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2802    return QualType(VTP, 0);
2803
2804  // If the element type isn't canonical, this won't be a canonical type either,
2805  // so fill in the canonical type field.
2806  QualType Canonical;
2807  if (!vecType.isCanonical()) {
2808    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
2809
2810    // Get the new insert position for the node we care about.
2811    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2812    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2813  }
2814  ExtVectorType *New = new (*this, TypeAlignment)
2815    ExtVectorType(vecType, NumElts, Canonical);
2816  VectorTypes.InsertNode(New, InsertPos);
2817  Types.push_back(New);
2818  return QualType(New, 0);
2819}
2820
2821QualType
2822ASTContext::getDependentSizedExtVectorType(QualType vecType,
2823                                           Expr *SizeExpr,
2824                                           SourceLocation AttrLoc) const {
2825  llvm::FoldingSetNodeID ID;
2826  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
2827                                       SizeExpr);
2828
2829  void *InsertPos = nullptr;
2830  DependentSizedExtVectorType *Canon
2831    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2832  DependentSizedExtVectorType *New;
2833  if (Canon) {
2834    // We already have a canonical version of this array type; use it as
2835    // the canonical type for a newly-built type.
2836    New = new (*this, TypeAlignment)
2837      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
2838                                  SizeExpr, AttrLoc);
2839  } else {
2840    QualType CanonVecTy = getCanonicalType(vecType);
2841    if (CanonVecTy == vecType) {
2842      New = new (*this, TypeAlignment)
2843        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
2844                                    AttrLoc);
2845
2846      DependentSizedExtVectorType *CanonCheck
2847        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2848      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
2849      (void)CanonCheck;
2850      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
2851    } else {
2852      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
2853                                                      SourceLocation());
2854      New = new (*this, TypeAlignment)
2855        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2856    }
2857  }
2858
2859  Types.push_back(New);
2860  return QualType(New, 0);
2861}
2862
2863/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
2864///
2865QualType
2866ASTContext::getFunctionNoProtoType(QualType ResultTy,
2867                                   const FunctionType::ExtInfo &Info) const {
2868  const CallingConv CallConv = Info.getCC();
2869
2870  // Unique functions, to guarantee there is only one function of a particular
2871  // structure.
2872  llvm::FoldingSetNodeID ID;
2873  FunctionNoProtoType::Profile(ID, ResultTy, Info);
2874
2875  void *InsertPos = nullptr;
2876  if (FunctionNoProtoType *FT =
2877        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2878    return QualType(FT, 0);
2879
2880  QualType Canonical;
2881  if (!ResultTy.isCanonical()) {
2882    Canonical = getFunctionNoProtoType(getCanonicalType(ResultTy), Info);
2883
2884    // Get the new insert position for the node we care about.
2885    FunctionNoProtoType *NewIP =
2886      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2887    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2888  }
2889
2890  FunctionProtoType::ExtInfo newInfo = Info.withCallingConv(CallConv);
2891  FunctionNoProtoType *New = new (*this, TypeAlignment)
2892    FunctionNoProtoType(ResultTy, Canonical, newInfo);
2893  Types.push_back(New);
2894  FunctionNoProtoTypes.InsertNode(New, InsertPos);
2895  return QualType(New, 0);
2896}
2897
2898/// \brief Determine whether \p T is canonical as the result type of a function.
2899static bool isCanonicalResultType(QualType T) {
2900  return T.isCanonical() &&
2901         (T.getObjCLifetime() == Qualifiers::OCL_None ||
2902          T.getObjCLifetime() == Qualifiers::OCL_ExplicitNone);
2903}
2904
2905QualType
2906ASTContext::getFunctionType(QualType ResultTy, ArrayRef<QualType> ArgArray,
2907                            const FunctionProtoType::ExtProtoInfo &EPI) const {
2908  size_t NumArgs = ArgArray.size();
2909
2910  // Unique functions, to guarantee there is only one function of a particular
2911  // structure.
2912  llvm::FoldingSetNodeID ID;
2913  FunctionProtoType::Profile(ID, ResultTy, ArgArray.begin(), NumArgs, EPI,
2914                             *this);
2915
2916  void *InsertPos = nullptr;
2917  if (FunctionProtoType *FTP =
2918        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2919    return QualType(FTP, 0);
2920
2921  // Determine whether the type being created is already canonical or not.
2922  bool isCanonical =
2923    EPI.ExceptionSpec.Type == EST_None && isCanonicalResultType(ResultTy) &&
2924    !EPI.HasTrailingReturn;
2925  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
2926    if (!ArgArray[i].isCanonicalAsParam())
2927      isCanonical = false;
2928
2929  // If this type isn't canonical, get the canonical version of it.
2930  // The exception spec is not part of the canonical type.
2931  QualType Canonical;
2932  if (!isCanonical) {
2933    SmallVector<QualType, 16> CanonicalArgs;
2934    CanonicalArgs.reserve(NumArgs);
2935    for (unsigned i = 0; i != NumArgs; ++i)
2936      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
2937
2938    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
2939    CanonicalEPI.HasTrailingReturn = false;
2940    CanonicalEPI.ExceptionSpec = FunctionProtoType::ExceptionSpecInfo();
2941
2942    // Result types do not have ARC lifetime qualifiers.
2943    QualType CanResultTy = getCanonicalType(ResultTy);
2944    if (ResultTy.getQualifiers().hasObjCLifetime()) {
2945      Qualifiers Qs = CanResultTy.getQualifiers();
2946      Qs.removeObjCLifetime();
2947      CanResultTy = getQualifiedType(CanResultTy.getUnqualifiedType(), Qs);
2948    }
2949
2950    Canonical = getFunctionType(CanResultTy, CanonicalArgs, CanonicalEPI);
2951
2952    // Get the new insert position for the node we care about.
2953    FunctionProtoType *NewIP =
2954      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2955    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
2956  }
2957
2958  // FunctionProtoType objects are allocated with extra bytes after
2959  // them for three variable size arrays at the end:
2960  //  - parameter types
2961  //  - exception types
2962  //  - consumed-arguments flags
2963  // Instead of the exception types, there could be a noexcept
2964  // expression, or information used to resolve the exception
2965  // specification.
2966  size_t Size = sizeof(FunctionProtoType) +
2967                NumArgs * sizeof(QualType);
2968  if (EPI.ExceptionSpec.Type == EST_Dynamic) {
2969    Size += EPI.ExceptionSpec.Exceptions.size() * sizeof(QualType);
2970  } else if (EPI.ExceptionSpec.Type == EST_ComputedNoexcept) {
2971    Size += sizeof(Expr*);
2972  } else if (EPI.ExceptionSpec.Type == EST_Uninstantiated) {
2973    Size += 2 * sizeof(FunctionDecl*);
2974  } else if (EPI.ExceptionSpec.Type == EST_Unevaluated) {
2975    Size += sizeof(FunctionDecl*);
2976  }
2977  if (EPI.ConsumedParameters)
2978    Size += NumArgs * sizeof(bool);
2979
2980  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
2981  FunctionProtoType::ExtProtoInfo newEPI = EPI;
2982  new (FTP) FunctionProtoType(ResultTy, ArgArray, Canonical, newEPI);
2983  Types.push_back(FTP);
2984  FunctionProtoTypes.InsertNode(FTP, InsertPos);
2985  return QualType(FTP, 0);
2986}
2987
2988#ifndef NDEBUG
2989static bool NeedsInjectedClassNameType(const RecordDecl *D) {
2990  if (!isa<CXXRecordDecl>(D)) return false;
2991  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
2992  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
2993    return true;
2994  if (RD->getDescribedClassTemplate() &&
2995      !isa<ClassTemplateSpecializationDecl>(RD))
2996    return true;
2997  return false;
2998}
2999#endif
3000
3001/// getInjectedClassNameType - Return the unique reference to the
3002/// injected class name type for the specified templated declaration.
3003QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
3004                                              QualType TST) const {
3005  assert(NeedsInjectedClassNameType(Decl));
3006  if (Decl->TypeForDecl) {
3007    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
3008  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDecl()) {
3009    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
3010    Decl->TypeForDecl = PrevDecl->TypeForDecl;
3011    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
3012  } else {
3013    Type *newType =
3014      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
3015    Decl->TypeForDecl = newType;
3016    Types.push_back(newType);
3017  }
3018  return QualType(Decl->TypeForDecl, 0);
3019}
3020
3021/// getTypeDeclType - Return the unique reference to the type for the
3022/// specified type declaration.
3023QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) const {
3024  assert(Decl && "Passed null for Decl param");
3025  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
3026
3027  if (const TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Decl))
3028    return getTypedefType(Typedef);
3029
3030  assert(!isa<TemplateTypeParmDecl>(Decl) &&
3031         "Template type parameter types are always available.");
3032
3033  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
3034    assert(Record->isFirstDecl() && "struct/union has previous declaration");
3035    assert(!NeedsInjectedClassNameType(Record));
3036    return getRecordType(Record);
3037  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
3038    assert(Enum->isFirstDecl() && "enum has previous declaration");
3039    return getEnumType(Enum);
3040  } else if (const UnresolvedUsingTypenameDecl *Using =
3041               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
3042    Type *newType = new (*this, TypeAlignment) UnresolvedUsingType(Using);
3043    Decl->TypeForDecl = newType;
3044    Types.push_back(newType);
3045  } else
3046    llvm_unreachable("TypeDecl without a type?");
3047
3048  return QualType(Decl->TypeForDecl, 0);
3049}
3050
3051/// getTypedefType - Return the unique reference to the type for the
3052/// specified typedef name decl.
3053QualType
3054ASTContext::getTypedefType(const TypedefNameDecl *Decl,
3055                           QualType Canonical) const {
3056  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
3057
3058  if (Canonical.isNull())
3059    Canonical = getCanonicalType(Decl->getUnderlyingType());
3060  TypedefType *newType = new(*this, TypeAlignment)
3061    TypedefType(Type::Typedef, Decl, Canonical);
3062  Decl->TypeForDecl = newType;
3063  Types.push_back(newType);
3064  return QualType(newType, 0);
3065}
3066
3067QualType ASTContext::getRecordType(const RecordDecl *Decl) const {
3068  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
3069
3070  if (const RecordDecl *PrevDecl = Decl->getPreviousDecl())
3071    if (PrevDecl->TypeForDecl)
3072      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
3073
3074  RecordType *newType = new (*this, TypeAlignment) RecordType(Decl);
3075  Decl->TypeForDecl = newType;
3076  Types.push_back(newType);
3077  return QualType(newType, 0);
3078}
3079
3080QualType ASTContext::getEnumType(const EnumDecl *Decl) const {
3081  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
3082
3083  if (const EnumDecl *PrevDecl = Decl->getPreviousDecl())
3084    if (PrevDecl->TypeForDecl)
3085      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
3086
3087  EnumType *newType = new (*this, TypeAlignment) EnumType(Decl);
3088  Decl->TypeForDecl = newType;
3089  Types.push_back(newType);
3090  return QualType(newType, 0);
3091}
3092
3093QualType ASTContext::getAttributedType(AttributedType::Kind attrKind,
3094                                       QualType modifiedType,
3095                                       QualType equivalentType) {
3096  llvm::FoldingSetNodeID id;
3097  AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
3098
3099  void *insertPos = nullptr;
3100  AttributedType *type = AttributedTypes.FindNodeOrInsertPos(id, insertPos);
3101  if (type) return QualType(type, 0);
3102
3103  QualType canon = getCanonicalType(equivalentType);
3104  type = new (*this, TypeAlignment)
3105           AttributedType(canon, attrKind, modifiedType, equivalentType);
3106
3107  Types.push_back(type);
3108  AttributedTypes.InsertNode(type, insertPos);
3109
3110  return QualType(type, 0);
3111}
3112
3113
3114/// \brief Retrieve a substitution-result type.
3115QualType
3116ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
3117                                         QualType Replacement) const {
3118  assert(Replacement.isCanonical()
3119         && "replacement types must always be canonical");
3120
3121  llvm::FoldingSetNodeID ID;
3122  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
3123  void *InsertPos = nullptr;
3124  SubstTemplateTypeParmType *SubstParm
3125    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
3126
3127  if (!SubstParm) {
3128    SubstParm = new (*this, TypeAlignment)
3129      SubstTemplateTypeParmType(Parm, Replacement);
3130    Types.push_back(SubstParm);
3131    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
3132  }
3133
3134  return QualType(SubstParm, 0);
3135}
3136
3137/// \brief Retrieve a
3138QualType ASTContext::getSubstTemplateTypeParmPackType(
3139                                          const TemplateTypeParmType *Parm,
3140                                              const TemplateArgument &ArgPack) {
3141#ifndef NDEBUG
3142  for (const auto &P : ArgPack.pack_elements()) {
3143    assert(P.getKind() == TemplateArgument::Type &&"Pack contains a non-type");
3144    assert(P.getAsType().isCanonical() && "Pack contains non-canonical type");
3145  }
3146#endif
3147
3148  llvm::FoldingSetNodeID ID;
3149  SubstTemplateTypeParmPackType::Profile(ID, Parm, ArgPack);
3150  void *InsertPos = nullptr;
3151  if (SubstTemplateTypeParmPackType *SubstParm
3152        = SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos))
3153    return QualType(SubstParm, 0);
3154
3155  QualType Canon;
3156  if (!Parm->isCanonicalUnqualified()) {
3157    Canon = getCanonicalType(QualType(Parm, 0));
3158    Canon = getSubstTemplateTypeParmPackType(cast<TemplateTypeParmType>(Canon),
3159                                             ArgPack);
3160    SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos);
3161  }
3162
3163  SubstTemplateTypeParmPackType *SubstParm
3164    = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
3165                                                               ArgPack);
3166  Types.push_back(SubstParm);
3167  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
3168  return QualType(SubstParm, 0);
3169}
3170
3171/// \brief Retrieve the template type parameter type for a template
3172/// parameter or parameter pack with the given depth, index, and (optionally)
3173/// name.
3174QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
3175                                             bool ParameterPack,
3176                                             TemplateTypeParmDecl *TTPDecl) const {
3177  llvm::FoldingSetNodeID ID;
3178  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, TTPDecl);
3179  void *InsertPos = nullptr;
3180  TemplateTypeParmType *TypeParm
3181    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
3182
3183  if (TypeParm)
3184    return QualType(TypeParm, 0);
3185
3186  if (TTPDecl) {
3187    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
3188    TypeParm = new (*this, TypeAlignment) TemplateTypeParmType(TTPDecl, Canon);
3189
3190    TemplateTypeParmType *TypeCheck
3191      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
3192    assert(!TypeCheck && "Template type parameter canonical type broken");
3193    (void)TypeCheck;
3194  } else
3195    TypeParm = new (*this, TypeAlignment)
3196      TemplateTypeParmType(Depth, Index, ParameterPack);
3197
3198  Types.push_back(TypeParm);
3199  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
3200
3201  return QualType(TypeParm, 0);
3202}
3203
3204TypeSourceInfo *
3205ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
3206                                              SourceLocation NameLoc,
3207                                        const TemplateArgumentListInfo &Args,
3208                                              QualType Underlying) const {
3209  assert(!Name.getAsDependentTemplateName() &&
3210         "No dependent template names here!");
3211  QualType TST = getTemplateSpecializationType(Name, Args, Underlying);
3212
3213  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
3214  TemplateSpecializationTypeLoc TL =
3215      DI->getTypeLoc().castAs<TemplateSpecializationTypeLoc>();
3216  TL.setTemplateKeywordLoc(SourceLocation());
3217  TL.setTemplateNameLoc(NameLoc);
3218  TL.setLAngleLoc(Args.getLAngleLoc());
3219  TL.setRAngleLoc(Args.getRAngleLoc());
3220  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
3221    TL.setArgLocInfo(i, Args[i].getLocInfo());
3222  return DI;
3223}
3224
3225QualType
3226ASTContext::getTemplateSpecializationType(TemplateName Template,
3227                                          const TemplateArgumentListInfo &Args,
3228                                          QualType Underlying) const {
3229  assert(!Template.getAsDependentTemplateName() &&
3230         "No dependent template names here!");
3231
3232  unsigned NumArgs = Args.size();
3233
3234  SmallVector<TemplateArgument, 4> ArgVec;
3235  ArgVec.reserve(NumArgs);
3236  for (unsigned i = 0; i != NumArgs; ++i)
3237    ArgVec.push_back(Args[i].getArgument());
3238
3239  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
3240                                       Underlying);
3241}
3242
3243#ifndef NDEBUG
3244static bool hasAnyPackExpansions(const TemplateArgument *Args,
3245                                 unsigned NumArgs) {
3246  for (unsigned I = 0; I != NumArgs; ++I)
3247    if (Args[I].isPackExpansion())
3248      return true;
3249
3250  return true;
3251}
3252#endif
3253
3254QualType
3255ASTContext::getTemplateSpecializationType(TemplateName Template,
3256                                          const TemplateArgument *Args,
3257                                          unsigned NumArgs,
3258                                          QualType Underlying) const {
3259  assert(!Template.getAsDependentTemplateName() &&
3260         "No dependent template names here!");
3261  // Look through qualified template names.
3262  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
3263    Template = TemplateName(QTN->getTemplateDecl());
3264
3265  bool IsTypeAlias =
3266    Template.getAsTemplateDecl() &&
3267    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
3268  QualType CanonType;
3269  if (!Underlying.isNull())
3270    CanonType = getCanonicalType(Underlying);
3271  else {
3272    // We can get here with an alias template when the specialization contains
3273    // a pack expansion that does not match up with a parameter pack.
3274    assert((!IsTypeAlias || hasAnyPackExpansions(Args, NumArgs)) &&
3275           "Caller must compute aliased type");
3276    IsTypeAlias = false;
3277    CanonType = getCanonicalTemplateSpecializationType(Template, Args,
3278                                                       NumArgs);
3279  }
3280
3281  // Allocate the (non-canonical) template specialization type, but don't
3282  // try to unique it: these types typically have location information that
3283  // we don't unique and don't want to lose.
3284  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
3285                       sizeof(TemplateArgument) * NumArgs +
3286                       (IsTypeAlias? sizeof(QualType) : 0),
3287                       TypeAlignment);
3288  TemplateSpecializationType *Spec
3289    = new (Mem) TemplateSpecializationType(Template, Args, NumArgs, CanonType,
3290                                         IsTypeAlias ? Underlying : QualType());
3291
3292  Types.push_back(Spec);
3293  return QualType(Spec, 0);
3294}
3295
3296QualType
3297ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
3298                                                   const TemplateArgument *Args,
3299                                                   unsigned NumArgs) const {
3300  assert(!Template.getAsDependentTemplateName() &&
3301         "No dependent template names here!");
3302
3303  // Look through qualified template names.
3304  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
3305    Template = TemplateName(QTN->getTemplateDecl());
3306
3307  // Build the canonical template specialization type.
3308  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
3309  SmallVector<TemplateArgument, 4> CanonArgs;
3310  CanonArgs.reserve(NumArgs);
3311  for (unsigned I = 0; I != NumArgs; ++I)
3312    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
3313
3314  // Determine whether this canonical template specialization type already
3315  // exists.
3316  llvm::FoldingSetNodeID ID;
3317  TemplateSpecializationType::Profile(ID, CanonTemplate,
3318                                      CanonArgs.data(), NumArgs, *this);
3319
3320  void *InsertPos = nullptr;
3321  TemplateSpecializationType *Spec
3322    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3323
3324  if (!Spec) {
3325    // Allocate a new canonical template specialization type.
3326    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
3327                          sizeof(TemplateArgument) * NumArgs),
3328                         TypeAlignment);
3329    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
3330                                                CanonArgs.data(), NumArgs,
3331                                                QualType(), QualType());
3332    Types.push_back(Spec);
3333    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
3334  }
3335
3336  assert(Spec->isDependentType() &&
3337         "Non-dependent template-id type must have a canonical type");
3338  return QualType(Spec, 0);
3339}
3340
3341QualType
3342ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
3343                              NestedNameSpecifier *NNS,
3344                              QualType NamedType) const {
3345  llvm::FoldingSetNodeID ID;
3346  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
3347
3348  void *InsertPos = nullptr;
3349  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
3350  if (T)
3351    return QualType(T, 0);
3352
3353  QualType Canon = NamedType;
3354  if (!Canon.isCanonical()) {
3355    Canon = getCanonicalType(NamedType);
3356    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
3357    assert(!CheckT && "Elaborated canonical type broken");
3358    (void)CheckT;
3359  }
3360
3361  T = new (*this, TypeAlignment) ElaboratedType(Keyword, NNS, NamedType, Canon);
3362  Types.push_back(T);
3363  ElaboratedTypes.InsertNode(T, InsertPos);
3364  return QualType(T, 0);
3365}
3366
3367QualType
3368ASTContext::getParenType(QualType InnerType) const {
3369  llvm::FoldingSetNodeID ID;
3370  ParenType::Profile(ID, InnerType);
3371
3372  void *InsertPos = nullptr;
3373  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
3374  if (T)
3375    return QualType(T, 0);
3376
3377  QualType Canon = InnerType;
3378  if (!Canon.isCanonical()) {
3379    Canon = getCanonicalType(InnerType);
3380    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
3381    assert(!CheckT && "Paren canonical type broken");
3382    (void)CheckT;
3383  }
3384
3385  T = new (*this, TypeAlignment) ParenType(InnerType, Canon);
3386  Types.push_back(T);
3387  ParenTypes.InsertNode(T, InsertPos);
3388  return QualType(T, 0);
3389}
3390
3391QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
3392                                          NestedNameSpecifier *NNS,
3393                                          const IdentifierInfo *Name,
3394                                          QualType Canon) const {
3395  if (Canon.isNull()) {
3396    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
3397    ElaboratedTypeKeyword CanonKeyword = Keyword;
3398    if (Keyword == ETK_None)
3399      CanonKeyword = ETK_Typename;
3400
3401    if (CanonNNS != NNS || CanonKeyword != Keyword)
3402      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
3403  }
3404
3405  llvm::FoldingSetNodeID ID;
3406  DependentNameType::Profile(ID, Keyword, NNS, Name);
3407
3408  void *InsertPos = nullptr;
3409  DependentNameType *T
3410    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
3411  if (T)
3412    return QualType(T, 0);
3413
3414  T = new (*this, TypeAlignment) DependentNameType(Keyword, NNS, Name, Canon);
3415  Types.push_back(T);
3416  DependentNameTypes.InsertNode(T, InsertPos);
3417  return QualType(T, 0);
3418}
3419
3420QualType
3421ASTContext::getDependentTemplateSpecializationType(
3422                                 ElaboratedTypeKeyword Keyword,
3423                                 NestedNameSpecifier *NNS,
3424                                 const IdentifierInfo *Name,
3425                                 const TemplateArgumentListInfo &Args) const {
3426  // TODO: avoid this copy
3427  SmallVector<TemplateArgument, 16> ArgCopy;
3428  for (unsigned I = 0, E = Args.size(); I != E; ++I)
3429    ArgCopy.push_back(Args[I].getArgument());
3430  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
3431                                                ArgCopy.size(),
3432                                                ArgCopy.data());
3433}
3434
3435QualType
3436ASTContext::getDependentTemplateSpecializationType(
3437                                 ElaboratedTypeKeyword Keyword,
3438                                 NestedNameSpecifier *NNS,
3439                                 const IdentifierInfo *Name,
3440                                 unsigned NumArgs,
3441                                 const TemplateArgument *Args) const {
3442  assert((!NNS || NNS->isDependent()) &&
3443         "nested-name-specifier must be dependent");
3444
3445  llvm::FoldingSetNodeID ID;
3446  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
3447                                               Name, NumArgs, Args);
3448
3449  void *InsertPos = nullptr;
3450  DependentTemplateSpecializationType *T
3451    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3452  if (T)
3453    return QualType(T, 0);
3454
3455  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
3456
3457  ElaboratedTypeKeyword CanonKeyword = Keyword;
3458  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
3459
3460  bool AnyNonCanonArgs = false;
3461  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
3462  for (unsigned I = 0; I != NumArgs; ++I) {
3463    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
3464    if (!CanonArgs[I].structurallyEquals(Args[I]))
3465      AnyNonCanonArgs = true;
3466  }
3467
3468  QualType Canon;
3469  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
3470    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
3471                                                   Name, NumArgs,
3472                                                   CanonArgs.data());
3473
3474    // Find the insert position again.
3475    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3476  }
3477
3478  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
3479                        sizeof(TemplateArgument) * NumArgs),
3480                       TypeAlignment);
3481  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
3482                                                    Name, NumArgs, Args, Canon);
3483  Types.push_back(T);
3484  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
3485  return QualType(T, 0);
3486}
3487
3488QualType ASTContext::getPackExpansionType(QualType Pattern,
3489                                          Optional<unsigned> NumExpansions) {
3490  llvm::FoldingSetNodeID ID;
3491  PackExpansionType::Profile(ID, Pattern, NumExpansions);
3492
3493  assert(Pattern->containsUnexpandedParameterPack() &&
3494         "Pack expansions must expand one or more parameter packs");
3495  void *InsertPos = nullptr;
3496  PackExpansionType *T
3497    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3498  if (T)
3499    return QualType(T, 0);
3500
3501  QualType Canon;
3502  if (!Pattern.isCanonical()) {
3503    Canon = getCanonicalType(Pattern);
3504    // The canonical type might not contain an unexpanded parameter pack, if it
3505    // contains an alias template specialization which ignores one of its
3506    // parameters.
3507    if (Canon->containsUnexpandedParameterPack()) {
3508      Canon = getPackExpansionType(Canon, NumExpansions);
3509
3510      // Find the insert position again, in case we inserted an element into
3511      // PackExpansionTypes and invalidated our insert position.
3512      PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3513    }
3514  }
3515
3516  T = new (*this, TypeAlignment)
3517      PackExpansionType(Pattern, Canon, NumExpansions);
3518  Types.push_back(T);
3519  PackExpansionTypes.InsertNode(T, InsertPos);
3520  return QualType(T, 0);
3521}
3522
3523/// CmpProtocolNames - Comparison predicate for sorting protocols
3524/// alphabetically.
3525static int CmpProtocolNames(ObjCProtocolDecl *const *LHS,
3526                            ObjCProtocolDecl *const *RHS) {
3527  return DeclarationName::compare((*LHS)->getDeclName(), (*RHS)->getDeclName());
3528}
3529
3530static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
3531                                unsigned NumProtocols) {
3532  if (NumProtocols == 0) return true;
3533
3534  if (Protocols[0]->getCanonicalDecl() != Protocols[0])
3535    return false;
3536
3537  for (unsigned i = 1; i != NumProtocols; ++i)
3538    if (CmpProtocolNames(&Protocols[i - 1], &Protocols[i]) >= 0 ||
3539        Protocols[i]->getCanonicalDecl() != Protocols[i])
3540      return false;
3541  return true;
3542}
3543
3544static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
3545                                   unsigned &NumProtocols) {
3546  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
3547
3548  // Sort protocols, keyed by name.
3549  llvm::array_pod_sort(Protocols, ProtocolsEnd, CmpProtocolNames);
3550
3551  // Canonicalize.
3552  for (unsigned I = 0, N = NumProtocols; I != N; ++I)
3553    Protocols[I] = Protocols[I]->getCanonicalDecl();
3554
3555  // Remove duplicates.
3556  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
3557  NumProtocols = ProtocolsEnd-Protocols;
3558}
3559
3560QualType ASTContext::getObjCObjectType(QualType BaseType,
3561                                       ObjCProtocolDecl * const *Protocols,
3562                                       unsigned NumProtocols) const {
3563  // If the base type is an interface and there aren't any protocols
3564  // to add, then the interface type will do just fine.
3565  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
3566    return BaseType;
3567
3568  // Look in the folding set for an existing type.
3569  llvm::FoldingSetNodeID ID;
3570  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
3571  void *InsertPos = nullptr;
3572  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
3573    return QualType(QT, 0);
3574
3575  // Build the canonical type, which has the canonical base type and
3576  // a sorted-and-uniqued list of protocols.
3577  QualType Canonical;
3578  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
3579  if (!ProtocolsSorted || !BaseType.isCanonical()) {
3580    if (!ProtocolsSorted) {
3581      SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
3582                                                     Protocols + NumProtocols);
3583      unsigned UniqueCount = NumProtocols;
3584
3585      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
3586      Canonical = getObjCObjectType(getCanonicalType(BaseType),
3587                                    &Sorted[0], UniqueCount);
3588    } else {
3589      Canonical = getObjCObjectType(getCanonicalType(BaseType),
3590                                    Protocols, NumProtocols);
3591    }
3592
3593    // Regenerate InsertPos.
3594    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
3595  }
3596
3597  unsigned Size = sizeof(ObjCObjectTypeImpl);
3598  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
3599  void *Mem = Allocate(Size, TypeAlignment);
3600  ObjCObjectTypeImpl *T =
3601    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
3602
3603  Types.push_back(T);
3604  ObjCObjectTypes.InsertNode(T, InsertPos);
3605  return QualType(T, 0);
3606}
3607
3608/// ObjCObjectAdoptsQTypeProtocols - Checks that protocols in IC's
3609/// protocol list adopt all protocols in QT's qualified-id protocol
3610/// list.
3611bool ASTContext::ObjCObjectAdoptsQTypeProtocols(QualType QT,
3612                                                ObjCInterfaceDecl *IC) {
3613  if (!QT->isObjCQualifiedIdType())
3614    return false;
3615
3616  if (const ObjCObjectPointerType *OPT = QT->getAs<ObjCObjectPointerType>()) {
3617    // If both the right and left sides have qualifiers.
3618    for (auto *Proto : OPT->quals()) {
3619      if (!IC->ClassImplementsProtocol(Proto, false))
3620        return false;
3621    }
3622    return true;
3623  }
3624  return false;
3625}
3626
3627/// QIdProtocolsAdoptObjCObjectProtocols - Checks that protocols in
3628/// QT's qualified-id protocol list adopt all protocols in IDecl's list
3629/// of protocols.
3630bool ASTContext::QIdProtocolsAdoptObjCObjectProtocols(QualType QT,
3631                                                ObjCInterfaceDecl *IDecl) {
3632  if (!QT->isObjCQualifiedIdType())
3633    return false;
3634  const ObjCObjectPointerType *OPT = QT->getAs<ObjCObjectPointerType>();
3635  if (!OPT)
3636    return false;
3637  if (!IDecl->hasDefinition())
3638    return false;
3639  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocols;
3640  CollectInheritedProtocols(IDecl, InheritedProtocols);
3641  if (InheritedProtocols.empty())
3642    return false;
3643  // Check that if every protocol in list of id<plist> conforms to a protcol
3644  // of IDecl's, then bridge casting is ok.
3645  bool Conforms = false;
3646  for (auto *Proto : OPT->quals()) {
3647    Conforms = false;
3648    for (auto *PI : InheritedProtocols) {
3649      if (ProtocolCompatibleWithProtocol(Proto, PI)) {
3650        Conforms = true;
3651        break;
3652      }
3653    }
3654    if (!Conforms)
3655      break;
3656  }
3657  if (Conforms)
3658    return true;
3659
3660  for (auto *PI : InheritedProtocols) {
3661    // If both the right and left sides have qualifiers.
3662    bool Adopts = false;
3663    for (auto *Proto : OPT->quals()) {
3664      // return 'true' if 'PI' is in the inheritance hierarchy of Proto
3665      if ((Adopts = ProtocolCompatibleWithProtocol(PI, Proto)))
3666        break;
3667    }
3668    if (!Adopts)
3669      return false;
3670  }
3671  return true;
3672}
3673
3674/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
3675/// the given object type.
3676QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
3677  llvm::FoldingSetNodeID ID;
3678  ObjCObjectPointerType::Profile(ID, ObjectT);
3679
3680  void *InsertPos = nullptr;
3681  if (ObjCObjectPointerType *QT =
3682              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
3683    return QualType(QT, 0);
3684
3685  // Find the canonical object type.
3686  QualType Canonical;
3687  if (!ObjectT.isCanonical()) {
3688    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
3689
3690    // Regenerate InsertPos.
3691    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
3692  }
3693
3694  // No match.
3695  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
3696  ObjCObjectPointerType *QType =
3697    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
3698
3699  Types.push_back(QType);
3700  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
3701  return QualType(QType, 0);
3702}
3703
3704/// getObjCInterfaceType - Return the unique reference to the type for the
3705/// specified ObjC interface decl. The list of protocols is optional.
3706QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
3707                                          ObjCInterfaceDecl *PrevDecl) const {
3708  if (Decl->TypeForDecl)
3709    return QualType(Decl->TypeForDecl, 0);
3710
3711  if (PrevDecl) {
3712    assert(PrevDecl->TypeForDecl && "previous decl has no TypeForDecl");
3713    Decl->TypeForDecl = PrevDecl->TypeForDecl;
3714    return QualType(PrevDecl->TypeForDecl, 0);
3715  }
3716
3717  // Prefer the definition, if there is one.
3718  if (const ObjCInterfaceDecl *Def = Decl->getDefinition())
3719    Decl = Def;
3720
3721  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
3722  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
3723  Decl->TypeForDecl = T;
3724  Types.push_back(T);
3725  return QualType(T, 0);
3726}
3727
3728/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
3729/// TypeOfExprType AST's (since expression's are never shared). For example,
3730/// multiple declarations that refer to "typeof(x)" all contain different
3731/// DeclRefExpr's. This doesn't effect the type checker, since it operates
3732/// on canonical type's (which are always unique).
3733QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
3734  TypeOfExprType *toe;
3735  if (tofExpr->isTypeDependent()) {
3736    llvm::FoldingSetNodeID ID;
3737    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
3738
3739    void *InsertPos = nullptr;
3740    DependentTypeOfExprType *Canon
3741      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
3742    if (Canon) {
3743      // We already have a "canonical" version of an identical, dependent
3744      // typeof(expr) type. Use that as our canonical type.
3745      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
3746                                          QualType((TypeOfExprType*)Canon, 0));
3747    } else {
3748      // Build a new, canonical typeof(expr) type.
3749      Canon
3750        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
3751      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
3752      toe = Canon;
3753    }
3754  } else {
3755    QualType Canonical = getCanonicalType(tofExpr->getType());
3756    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
3757  }
3758  Types.push_back(toe);
3759  return QualType(toe, 0);
3760}
3761
3762/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
3763/// TypeOfType nodes. The only motivation to unique these nodes would be
3764/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
3765/// an issue. This doesn't affect the type checker, since it operates
3766/// on canonical types (which are always unique).
3767QualType ASTContext::getTypeOfType(QualType tofType) const {
3768  QualType Canonical = getCanonicalType(tofType);
3769  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
3770  Types.push_back(tot);
3771  return QualType(tot, 0);
3772}
3773
3774
3775/// \brief Unlike many "get<Type>" functions, we don't unique DecltypeType
3776/// nodes. This would never be helpful, since each such type has its own
3777/// expression, and would not give a significant memory saving, since there
3778/// is an Expr tree under each such type.
3779QualType ASTContext::getDecltypeType(Expr *e, QualType UnderlyingType) const {
3780  DecltypeType *dt;
3781
3782  // C++11 [temp.type]p2:
3783  //   If an expression e involves a template parameter, decltype(e) denotes a
3784  //   unique dependent type. Two such decltype-specifiers refer to the same
3785  //   type only if their expressions are equivalent (14.5.6.1).
3786  if (e->isInstantiationDependent()) {
3787    llvm::FoldingSetNodeID ID;
3788    DependentDecltypeType::Profile(ID, *this, e);
3789
3790    void *InsertPos = nullptr;
3791    DependentDecltypeType *Canon
3792      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
3793    if (!Canon) {
3794      // Build a new, canonical typeof(expr) type.
3795      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
3796      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
3797    }
3798    dt = new (*this, TypeAlignment)
3799        DecltypeType(e, UnderlyingType, QualType((DecltypeType *)Canon, 0));
3800  } else {
3801    dt = new (*this, TypeAlignment)
3802        DecltypeType(e, UnderlyingType, getCanonicalType(UnderlyingType));
3803  }
3804  Types.push_back(dt);
3805  return QualType(dt, 0);
3806}
3807
3808/// getUnaryTransformationType - We don't unique these, since the memory
3809/// savings are minimal and these are rare.
3810QualType ASTContext::getUnaryTransformType(QualType BaseType,
3811                                           QualType UnderlyingType,
3812                                           UnaryTransformType::UTTKind Kind)
3813    const {
3814  UnaryTransformType *Ty =
3815    new (*this, TypeAlignment) UnaryTransformType (BaseType, UnderlyingType,
3816                                                   Kind,
3817                                 UnderlyingType->isDependentType() ?
3818                                 QualType() : getCanonicalType(UnderlyingType));
3819  Types.push_back(Ty);
3820  return QualType(Ty, 0);
3821}
3822
3823/// getAutoType - Return the uniqued reference to the 'auto' type which has been
3824/// deduced to the given type, or to the canonical undeduced 'auto' type, or the
3825/// canonical deduced-but-dependent 'auto' type.
3826QualType ASTContext::getAutoType(QualType DeducedType, bool IsDecltypeAuto,
3827                                 bool IsDependent) const {
3828  if (DeducedType.isNull() && !IsDecltypeAuto && !IsDependent)
3829    return getAutoDeductType();
3830
3831  // Look in the folding set for an existing type.
3832  void *InsertPos = nullptr;
3833  llvm::FoldingSetNodeID ID;
3834  AutoType::Profile(ID, DeducedType, IsDecltypeAuto, IsDependent);
3835  if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
3836    return QualType(AT, 0);
3837
3838  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType,
3839                                                     IsDecltypeAuto,
3840                                                     IsDependent);
3841  Types.push_back(AT);
3842  if (InsertPos)
3843    AutoTypes.InsertNode(AT, InsertPos);
3844  return QualType(AT, 0);
3845}
3846
3847/// getAtomicType - Return the uniqued reference to the atomic type for
3848/// the given value type.
3849QualType ASTContext::getAtomicType(QualType T) const {
3850  // Unique pointers, to guarantee there is only one pointer of a particular
3851  // structure.
3852  llvm::FoldingSetNodeID ID;
3853  AtomicType::Profile(ID, T);
3854
3855  void *InsertPos = nullptr;
3856  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
3857    return QualType(AT, 0);
3858
3859  // If the atomic value type isn't canonical, this won't be a canonical type
3860  // either, so fill in the canonical type field.
3861  QualType Canonical;
3862  if (!T.isCanonical()) {
3863    Canonical = getAtomicType(getCanonicalType(T));
3864
3865    // Get the new insert position for the node we care about.
3866    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
3867    assert(!NewIP && "Shouldn't be in the map!"); (void)NewIP;
3868  }
3869  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
3870  Types.push_back(New);
3871  AtomicTypes.InsertNode(New, InsertPos);
3872  return QualType(New, 0);
3873}
3874
3875/// getAutoDeductType - Get type pattern for deducing against 'auto'.
3876QualType ASTContext::getAutoDeductType() const {
3877  if (AutoDeductTy.isNull())
3878    AutoDeductTy = QualType(
3879      new (*this, TypeAlignment) AutoType(QualType(), /*decltype(auto)*/false,
3880                                          /*dependent*/false),
3881      0);
3882  return AutoDeductTy;
3883}
3884
3885/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
3886QualType ASTContext::getAutoRRefDeductType() const {
3887  if (AutoRRefDeductTy.isNull())
3888    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
3889  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
3890  return AutoRRefDeductTy;
3891}
3892
3893/// getTagDeclType - Return the unique reference to the type for the
3894/// specified TagDecl (struct/union/class/enum) decl.
3895QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
3896  assert (Decl);
3897  // FIXME: What is the design on getTagDeclType when it requires casting
3898  // away const?  mutable?
3899  return getTypeDeclType(const_cast<TagDecl*>(Decl));
3900}
3901
3902/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
3903/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
3904/// needs to agree with the definition in <stddef.h>.
3905CanQualType ASTContext::getSizeType() const {
3906  return getFromTargetType(Target->getSizeType());
3907}
3908
3909/// getIntMaxType - Return the unique type for "intmax_t" (C99 7.18.1.5).
3910CanQualType ASTContext::getIntMaxType() const {
3911  return getFromTargetType(Target->getIntMaxType());
3912}
3913
3914/// getUIntMaxType - Return the unique type for "uintmax_t" (C99 7.18.1.5).
3915CanQualType ASTContext::getUIntMaxType() const {
3916  return getFromTargetType(Target->getUIntMaxType());
3917}
3918
3919/// getSignedWCharType - Return the type of "signed wchar_t".
3920/// Used when in C++, as a GCC extension.
3921QualType ASTContext::getSignedWCharType() const {
3922  // FIXME: derive from "Target" ?
3923  return WCharTy;
3924}
3925
3926/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
3927/// Used when in C++, as a GCC extension.
3928QualType ASTContext::getUnsignedWCharType() const {
3929  // FIXME: derive from "Target" ?
3930  return UnsignedIntTy;
3931}
3932
3933QualType ASTContext::getIntPtrType() const {
3934  return getFromTargetType(Target->getIntPtrType());
3935}
3936
3937QualType ASTContext::getUIntPtrType() const {
3938  return getCorrespondingUnsignedType(getIntPtrType());
3939}
3940
3941/// getPointerDiffType - Return the unique type for "ptrdiff_t" (C99 7.17)
3942/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
3943QualType ASTContext::getPointerDiffType() const {
3944  return getFromTargetType(Target->getPtrDiffType(0));
3945}
3946
3947/// \brief Return the unique type for "pid_t" defined in
3948/// <sys/types.h>. We need this to compute the correct type for vfork().
3949QualType ASTContext::getProcessIDType() const {
3950  return getFromTargetType(Target->getProcessIDType());
3951}
3952
3953//===----------------------------------------------------------------------===//
3954//                              Type Operators
3955//===----------------------------------------------------------------------===//
3956
3957CanQualType ASTContext::getCanonicalParamType(QualType T) const {
3958  // Push qualifiers into arrays, and then discard any remaining
3959  // qualifiers.
3960  T = getCanonicalType(T);
3961  T = getVariableArrayDecayedType(T);
3962  const Type *Ty = T.getTypePtr();
3963  QualType Result;
3964  if (isa<ArrayType>(Ty)) {
3965    Result = getArrayDecayedType(QualType(Ty,0));
3966  } else if (isa<FunctionType>(Ty)) {
3967    Result = getPointerType(QualType(Ty, 0));
3968  } else {
3969    Result = QualType(Ty, 0);
3970  }
3971
3972  return CanQualType::CreateUnsafe(Result);
3973}
3974
3975QualType ASTContext::getUnqualifiedArrayType(QualType type,
3976                                             Qualifiers &quals) {
3977  SplitQualType splitType = type.getSplitUnqualifiedType();
3978
3979  // FIXME: getSplitUnqualifiedType() actually walks all the way to
3980  // the unqualified desugared type and then drops it on the floor.
3981  // We then have to strip that sugar back off with
3982  // getUnqualifiedDesugaredType(), which is silly.
3983  const ArrayType *AT =
3984    dyn_cast<ArrayType>(splitType.Ty->getUnqualifiedDesugaredType());
3985
3986  // If we don't have an array, just use the results in splitType.
3987  if (!AT) {
3988    quals = splitType.Quals;
3989    return QualType(splitType.Ty, 0);
3990  }
3991
3992  // Otherwise, recurse on the array's element type.
3993  QualType elementType = AT->getElementType();
3994  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
3995
3996  // If that didn't change the element type, AT has no qualifiers, so we
3997  // can just use the results in splitType.
3998  if (elementType == unqualElementType) {
3999    assert(quals.empty()); // from the recursive call
4000    quals = splitType.Quals;
4001    return QualType(splitType.Ty, 0);
4002  }
4003
4004  // Otherwise, add in the qualifiers from the outermost type, then
4005  // build the type back up.
4006  quals.addConsistentQualifiers(splitType.Quals);
4007
4008  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
4009    return getConstantArrayType(unqualElementType, CAT->getSize(),
4010                                CAT->getSizeModifier(), 0);
4011  }
4012
4013  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
4014    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
4015  }
4016
4017  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
4018    return getVariableArrayType(unqualElementType,
4019                                VAT->getSizeExpr(),
4020                                VAT->getSizeModifier(),
4021                                VAT->getIndexTypeCVRQualifiers(),
4022                                VAT->getBracketsRange());
4023  }
4024
4025  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
4026  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
4027                                    DSAT->getSizeModifier(), 0,
4028                                    SourceRange());
4029}
4030
4031/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
4032/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
4033/// they point to and return true. If T1 and T2 aren't pointer types
4034/// or pointer-to-member types, or if they are not similar at this
4035/// level, returns false and leaves T1 and T2 unchanged. Top-level
4036/// qualifiers on T1 and T2 are ignored. This function will typically
4037/// be called in a loop that successively "unwraps" pointer and
4038/// pointer-to-member types to compare them at each level.
4039bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
4040  const PointerType *T1PtrType = T1->getAs<PointerType>(),
4041                    *T2PtrType = T2->getAs<PointerType>();
4042  if (T1PtrType && T2PtrType) {
4043    T1 = T1PtrType->getPointeeType();
4044    T2 = T2PtrType->getPointeeType();
4045    return true;
4046  }
4047
4048  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
4049                          *T2MPType = T2->getAs<MemberPointerType>();
4050  if (T1MPType && T2MPType &&
4051      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
4052                             QualType(T2MPType->getClass(), 0))) {
4053    T1 = T1MPType->getPointeeType();
4054    T2 = T2MPType->getPointeeType();
4055    return true;
4056  }
4057
4058  if (getLangOpts().ObjC1) {
4059    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
4060                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
4061    if (T1OPType && T2OPType) {
4062      T1 = T1OPType->getPointeeType();
4063      T2 = T2OPType->getPointeeType();
4064      return true;
4065    }
4066  }
4067
4068  // FIXME: Block pointers, too?
4069
4070  return false;
4071}
4072
4073DeclarationNameInfo
4074ASTContext::getNameForTemplate(TemplateName Name,
4075                               SourceLocation NameLoc) const {
4076  switch (Name.getKind()) {
4077  case TemplateName::QualifiedTemplate:
4078  case TemplateName::Template:
4079    // DNInfo work in progress: CHECKME: what about DNLoc?
4080    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
4081                               NameLoc);
4082
4083  case TemplateName::OverloadedTemplate: {
4084    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
4085    // DNInfo work in progress: CHECKME: what about DNLoc?
4086    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
4087  }
4088
4089  case TemplateName::DependentTemplate: {
4090    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
4091    DeclarationName DName;
4092    if (DTN->isIdentifier()) {
4093      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
4094      return DeclarationNameInfo(DName, NameLoc);
4095    } else {
4096      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
4097      // DNInfo work in progress: FIXME: source locations?
4098      DeclarationNameLoc DNLoc;
4099      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
4100      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
4101      return DeclarationNameInfo(DName, NameLoc, DNLoc);
4102    }
4103  }
4104
4105  case TemplateName::SubstTemplateTemplateParm: {
4106    SubstTemplateTemplateParmStorage *subst
4107      = Name.getAsSubstTemplateTemplateParm();
4108    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
4109                               NameLoc);
4110  }
4111
4112  case TemplateName::SubstTemplateTemplateParmPack: {
4113    SubstTemplateTemplateParmPackStorage *subst
4114      = Name.getAsSubstTemplateTemplateParmPack();
4115    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
4116                               NameLoc);
4117  }
4118  }
4119
4120  llvm_unreachable("bad template name kind!");
4121}
4122
4123TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
4124  switch (Name.getKind()) {
4125  case TemplateName::QualifiedTemplate:
4126  case TemplateName::Template: {
4127    TemplateDecl *Template = Name.getAsTemplateDecl();
4128    if (TemplateTemplateParmDecl *TTP
4129          = dyn_cast<TemplateTemplateParmDecl>(Template))
4130      Template = getCanonicalTemplateTemplateParmDecl(TTP);
4131
4132    // The canonical template name is the canonical template declaration.
4133    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
4134  }
4135
4136  case TemplateName::OverloadedTemplate:
4137    llvm_unreachable("cannot canonicalize overloaded template");
4138
4139  case TemplateName::DependentTemplate: {
4140    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
4141    assert(DTN && "Non-dependent template names must refer to template decls.");
4142    return DTN->CanonicalTemplateName;
4143  }
4144
4145  case TemplateName::SubstTemplateTemplateParm: {
4146    SubstTemplateTemplateParmStorage *subst
4147      = Name.getAsSubstTemplateTemplateParm();
4148    return getCanonicalTemplateName(subst->getReplacement());
4149  }
4150
4151  case TemplateName::SubstTemplateTemplateParmPack: {
4152    SubstTemplateTemplateParmPackStorage *subst
4153                                  = Name.getAsSubstTemplateTemplateParmPack();
4154    TemplateTemplateParmDecl *canonParameter
4155      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
4156    TemplateArgument canonArgPack
4157      = getCanonicalTemplateArgument(subst->getArgumentPack());
4158    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
4159  }
4160  }
4161
4162  llvm_unreachable("bad template name!");
4163}
4164
4165bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
4166  X = getCanonicalTemplateName(X);
4167  Y = getCanonicalTemplateName(Y);
4168  return X.getAsVoidPointer() == Y.getAsVoidPointer();
4169}
4170
4171TemplateArgument
4172ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
4173  switch (Arg.getKind()) {
4174    case TemplateArgument::Null:
4175      return Arg;
4176
4177    case TemplateArgument::Expression:
4178      return Arg;
4179
4180    case TemplateArgument::Declaration: {
4181      ValueDecl *D = cast<ValueDecl>(Arg.getAsDecl()->getCanonicalDecl());
4182      return TemplateArgument(D, Arg.getParamTypeForDecl());
4183    }
4184
4185    case TemplateArgument::NullPtr:
4186      return TemplateArgument(getCanonicalType(Arg.getNullPtrType()),
4187                              /*isNullPtr*/true);
4188
4189    case TemplateArgument::Template:
4190      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
4191
4192    case TemplateArgument::TemplateExpansion:
4193      return TemplateArgument(getCanonicalTemplateName(
4194                                         Arg.getAsTemplateOrTemplatePattern()),
4195                              Arg.getNumTemplateExpansions());
4196
4197    case TemplateArgument::Integral:
4198      return TemplateArgument(Arg, getCanonicalType(Arg.getIntegralType()));
4199
4200    case TemplateArgument::Type:
4201      return TemplateArgument(getCanonicalType(Arg.getAsType()));
4202
4203    case TemplateArgument::Pack: {
4204      if (Arg.pack_size() == 0)
4205        return Arg;
4206
4207      TemplateArgument *CanonArgs
4208        = new (*this) TemplateArgument[Arg.pack_size()];
4209      unsigned Idx = 0;
4210      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
4211                                        AEnd = Arg.pack_end();
4212           A != AEnd; (void)++A, ++Idx)
4213        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
4214
4215      return TemplateArgument(CanonArgs, Arg.pack_size());
4216    }
4217  }
4218
4219  // Silence GCC warning
4220  llvm_unreachable("Unhandled template argument kind");
4221}
4222
4223NestedNameSpecifier *
4224ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
4225  if (!NNS)
4226    return nullptr;
4227
4228  switch (NNS->getKind()) {
4229  case NestedNameSpecifier::Identifier:
4230    // Canonicalize the prefix but keep the identifier the same.
4231    return NestedNameSpecifier::Create(*this,
4232                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
4233                                       NNS->getAsIdentifier());
4234
4235  case NestedNameSpecifier::Namespace:
4236    // A namespace is canonical; build a nested-name-specifier with
4237    // this namespace and no prefix.
4238    return NestedNameSpecifier::Create(*this, nullptr,
4239                                 NNS->getAsNamespace()->getOriginalNamespace());
4240
4241  case NestedNameSpecifier::NamespaceAlias:
4242    // A namespace is canonical; build a nested-name-specifier with
4243    // this namespace and no prefix.
4244    return NestedNameSpecifier::Create(*this, nullptr,
4245                                    NNS->getAsNamespaceAlias()->getNamespace()
4246                                                      ->getOriginalNamespace());
4247
4248  case NestedNameSpecifier::TypeSpec:
4249  case NestedNameSpecifier::TypeSpecWithTemplate: {
4250    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
4251
4252    // If we have some kind of dependent-named type (e.g., "typename T::type"),
4253    // break it apart into its prefix and identifier, then reconsititute those
4254    // as the canonical nested-name-specifier. This is required to canonicalize
4255    // a dependent nested-name-specifier involving typedefs of dependent-name
4256    // types, e.g.,
4257    //   typedef typename T::type T1;
4258    //   typedef typename T1::type T2;
4259    if (const DependentNameType *DNT = T->getAs<DependentNameType>())
4260      return NestedNameSpecifier::Create(*this, DNT->getQualifier(),
4261                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
4262
4263    // Otherwise, just canonicalize the type, and force it to be a TypeSpec.
4264    // FIXME: Why are TypeSpec and TypeSpecWithTemplate distinct in the
4265    // first place?
4266    return NestedNameSpecifier::Create(*this, nullptr, false,
4267                                       const_cast<Type *>(T.getTypePtr()));
4268  }
4269
4270  case NestedNameSpecifier::Global:
4271  case NestedNameSpecifier::Super:
4272    // The global specifier and __super specifer are canonical and unique.
4273    return NNS;
4274  }
4275
4276  llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
4277}
4278
4279
4280const ArrayType *ASTContext::getAsArrayType(QualType T) const {
4281  // Handle the non-qualified case efficiently.
4282  if (!T.hasLocalQualifiers()) {
4283    // Handle the common positive case fast.
4284    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
4285      return AT;
4286  }
4287
4288  // Handle the common negative case fast.
4289  if (!isa<ArrayType>(T.getCanonicalType()))
4290    return nullptr;
4291
4292  // Apply any qualifiers from the array type to the element type.  This
4293  // implements C99 6.7.3p8: "If the specification of an array type includes
4294  // any type qualifiers, the element type is so qualified, not the array type."
4295
4296  // If we get here, we either have type qualifiers on the type, or we have
4297  // sugar such as a typedef in the way.  If we have type qualifiers on the type
4298  // we must propagate them down into the element type.
4299
4300  SplitQualType split = T.getSplitDesugaredType();
4301  Qualifiers qs = split.Quals;
4302
4303  // If we have a simple case, just return now.
4304  const ArrayType *ATy = dyn_cast<ArrayType>(split.Ty);
4305  if (!ATy || qs.empty())
4306    return ATy;
4307
4308  // Otherwise, we have an array and we have qualifiers on it.  Push the
4309  // qualifiers into the array element type and return a new array type.
4310  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
4311
4312  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
4313    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
4314                                                CAT->getSizeModifier(),
4315                                           CAT->getIndexTypeCVRQualifiers()));
4316  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
4317    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
4318                                                  IAT->getSizeModifier(),
4319                                           IAT->getIndexTypeCVRQualifiers()));
4320
4321  if (const DependentSizedArrayType *DSAT
4322        = dyn_cast<DependentSizedArrayType>(ATy))
4323    return cast<ArrayType>(
4324                     getDependentSizedArrayType(NewEltTy,
4325                                                DSAT->getSizeExpr(),
4326                                                DSAT->getSizeModifier(),
4327                                              DSAT->getIndexTypeCVRQualifiers(),
4328                                                DSAT->getBracketsRange()));
4329
4330  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
4331  return cast<ArrayType>(getVariableArrayType(NewEltTy,
4332                                              VAT->getSizeExpr(),
4333                                              VAT->getSizeModifier(),
4334                                              VAT->getIndexTypeCVRQualifiers(),
4335                                              VAT->getBracketsRange()));
4336}
4337
4338QualType ASTContext::getAdjustedParameterType(QualType T) const {
4339  if (T->isArrayType() || T->isFunctionType())
4340    return getDecayedType(T);
4341  return T;
4342}
4343
4344QualType ASTContext::getSignatureParameterType(QualType T) const {
4345  T = getVariableArrayDecayedType(T);
4346  T = getAdjustedParameterType(T);
4347  return T.getUnqualifiedType();
4348}
4349
4350QualType ASTContext::getExceptionObjectType(QualType T) const {
4351  // C++ [except.throw]p3:
4352  //   A throw-expression initializes a temporary object, called the exception
4353  //   object, the type of which is determined by removing any top-level
4354  //   cv-qualifiers from the static type of the operand of throw and adjusting
4355  //   the type from "array of T" or "function returning T" to "pointer to T"
4356  //   or "pointer to function returning T", [...]
4357  T = getVariableArrayDecayedType(T);
4358  if (T->isArrayType() || T->isFunctionType())
4359    T = getDecayedType(T);
4360  return T.getUnqualifiedType();
4361}
4362
4363/// getArrayDecayedType - Return the properly qualified result of decaying the
4364/// specified array type to a pointer.  This operation is non-trivial when
4365/// handling typedefs etc.  The canonical type of "T" must be an array type,
4366/// this returns a pointer to a properly qualified element of the array.
4367///
4368/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
4369QualType ASTContext::getArrayDecayedType(QualType Ty) const {
4370  // Get the element type with 'getAsArrayType' so that we don't lose any
4371  // typedefs in the element type of the array.  This also handles propagation
4372  // of type qualifiers from the array type into the element type if present
4373  // (C99 6.7.3p8).
4374  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
4375  assert(PrettyArrayType && "Not an array type!");
4376
4377  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
4378
4379  // int x[restrict 4] ->  int *restrict
4380  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
4381}
4382
4383QualType ASTContext::getBaseElementType(const ArrayType *array) const {
4384  return getBaseElementType(array->getElementType());
4385}
4386
4387QualType ASTContext::getBaseElementType(QualType type) const {
4388  Qualifiers qs;
4389  while (true) {
4390    SplitQualType split = type.getSplitDesugaredType();
4391    const ArrayType *array = split.Ty->getAsArrayTypeUnsafe();
4392    if (!array) break;
4393
4394    type = array->getElementType();
4395    qs.addConsistentQualifiers(split.Quals);
4396  }
4397
4398  return getQualifiedType(type, qs);
4399}
4400
4401/// getConstantArrayElementCount - Returns number of constant array elements.
4402uint64_t
4403ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
4404  uint64_t ElementCount = 1;
4405  do {
4406    ElementCount *= CA->getSize().getZExtValue();
4407    CA = dyn_cast_or_null<ConstantArrayType>(
4408      CA->getElementType()->getAsArrayTypeUnsafe());
4409  } while (CA);
4410  return ElementCount;
4411}
4412
4413/// getFloatingRank - Return a relative rank for floating point types.
4414/// This routine will assert if passed a built-in type that isn't a float.
4415static FloatingRank getFloatingRank(QualType T) {
4416  if (const ComplexType *CT = T->getAs<ComplexType>())
4417    return getFloatingRank(CT->getElementType());
4418
4419  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
4420  switch (T->getAs<BuiltinType>()->getKind()) {
4421  default: llvm_unreachable("getFloatingRank(): not a floating type");
4422  case BuiltinType::Half:       return HalfRank;
4423  case BuiltinType::Float:      return FloatRank;
4424  case BuiltinType::Double:     return DoubleRank;
4425  case BuiltinType::LongDouble: return LongDoubleRank;
4426  }
4427}
4428
4429/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
4430/// point or a complex type (based on typeDomain/typeSize).
4431/// 'typeDomain' is a real floating point or complex type.
4432/// 'typeSize' is a real floating point or complex type.
4433QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
4434                                                       QualType Domain) const {
4435  FloatingRank EltRank = getFloatingRank(Size);
4436  if (Domain->isComplexType()) {
4437    switch (EltRank) {
4438    case HalfRank: llvm_unreachable("Complex half is not supported");
4439    case FloatRank:      return FloatComplexTy;
4440    case DoubleRank:     return DoubleComplexTy;
4441    case LongDoubleRank: return LongDoubleComplexTy;
4442    }
4443  }
4444
4445  assert(Domain->isRealFloatingType() && "Unknown domain!");
4446  switch (EltRank) {
4447  case HalfRank:       return HalfTy;
4448  case FloatRank:      return FloatTy;
4449  case DoubleRank:     return DoubleTy;
4450  case LongDoubleRank: return LongDoubleTy;
4451  }
4452  llvm_unreachable("getFloatingRank(): illegal value for rank");
4453}
4454
4455/// getFloatingTypeOrder - Compare the rank of the two specified floating
4456/// point types, ignoring the domain of the type (i.e. 'double' ==
4457/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
4458/// LHS < RHS, return -1.
4459int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
4460  FloatingRank LHSR = getFloatingRank(LHS);
4461  FloatingRank RHSR = getFloatingRank(RHS);
4462
4463  if (LHSR == RHSR)
4464    return 0;
4465  if (LHSR > RHSR)
4466    return 1;
4467  return -1;
4468}
4469
4470/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
4471/// routine will assert if passed a built-in type that isn't an integer or enum,
4472/// or if it is not canonicalized.
4473unsigned ASTContext::getIntegerRank(const Type *T) const {
4474  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
4475
4476  switch (cast<BuiltinType>(T)->getKind()) {
4477  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
4478  case BuiltinType::Bool:
4479    return 1 + (getIntWidth(BoolTy) << 3);
4480  case BuiltinType::Char_S:
4481  case BuiltinType::Char_U:
4482  case BuiltinType::SChar:
4483  case BuiltinType::UChar:
4484    return 2 + (getIntWidth(CharTy) << 3);
4485  case BuiltinType::Short:
4486  case BuiltinType::UShort:
4487    return 3 + (getIntWidth(ShortTy) << 3);
4488  case BuiltinType::Int:
4489  case BuiltinType::UInt:
4490    return 4 + (getIntWidth(IntTy) << 3);
4491  case BuiltinType::Long:
4492  case BuiltinType::ULong:
4493    return 5 + (getIntWidth(LongTy) << 3);
4494  case BuiltinType::LongLong:
4495  case BuiltinType::ULongLong:
4496    return 6 + (getIntWidth(LongLongTy) << 3);
4497  case BuiltinType::Int128:
4498  case BuiltinType::UInt128:
4499    return 7 + (getIntWidth(Int128Ty) << 3);
4500  }
4501}
4502
4503/// \brief Whether this is a promotable bitfield reference according
4504/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
4505///
4506/// \returns the type this bit-field will promote to, or NULL if no
4507/// promotion occurs.
4508QualType ASTContext::isPromotableBitField(Expr *E) const {
4509  if (E->isTypeDependent() || E->isValueDependent())
4510    return QualType();
4511
4512  // FIXME: We should not do this unless E->refersToBitField() is true. This
4513  // matters in C where getSourceBitField() will find bit-fields for various
4514  // cases where the source expression is not a bit-field designator.
4515
4516  FieldDecl *Field = E->getSourceBitField(); // FIXME: conditional bit-fields?
4517  if (!Field)
4518    return QualType();
4519
4520  QualType FT = Field->getType();
4521
4522  uint64_t BitWidth = Field->getBitWidthValue(*this);
4523  uint64_t IntSize = getTypeSize(IntTy);
4524  // C++ [conv.prom]p5:
4525  //   A prvalue for an integral bit-field can be converted to a prvalue of type
4526  //   int if int can represent all the values of the bit-field; otherwise, it
4527  //   can be converted to unsigned int if unsigned int can represent all the
4528  //   values of the bit-field. If the bit-field is larger yet, no integral
4529  //   promotion applies to it.
4530  // C11 6.3.1.1/2:
4531  //   [For a bit-field of type _Bool, int, signed int, or unsigned int:]
4532  //   If an int can represent all values of the original type (as restricted by
4533  //   the width, for a bit-field), the value is converted to an int; otherwise,
4534  //   it is converted to an unsigned int.
4535  //
4536  // FIXME: C does not permit promotion of a 'long : 3' bitfield to int.
4537  //        We perform that promotion here to match GCC and C++.
4538  if (BitWidth < IntSize)
4539    return IntTy;
4540
4541  if (BitWidth == IntSize)
4542    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
4543
4544  // Types bigger than int are not subject to promotions, and therefore act
4545  // like the base type. GCC has some weird bugs in this area that we
4546  // deliberately do not follow (GCC follows a pre-standard resolution to
4547  // C's DR315 which treats bit-width as being part of the type, and this leaks
4548  // into their semantics in some cases).
4549  return QualType();
4550}
4551
4552/// getPromotedIntegerType - Returns the type that Promotable will
4553/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
4554/// integer type.
4555QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
4556  assert(!Promotable.isNull());
4557  assert(Promotable->isPromotableIntegerType());
4558  if (const EnumType *ET = Promotable->getAs<EnumType>())
4559    return ET->getDecl()->getPromotionType();
4560
4561  if (const BuiltinType *BT = Promotable->getAs<BuiltinType>()) {
4562    // C++ [conv.prom]: A prvalue of type char16_t, char32_t, or wchar_t
4563    // (3.9.1) can be converted to a prvalue of the first of the following
4564    // types that can represent all the values of its underlying type:
4565    // int, unsigned int, long int, unsigned long int, long long int, or
4566    // unsigned long long int [...]
4567    // FIXME: Is there some better way to compute this?
4568    if (BT->getKind() == BuiltinType::WChar_S ||
4569        BT->getKind() == BuiltinType::WChar_U ||
4570        BT->getKind() == BuiltinType::Char16 ||
4571        BT->getKind() == BuiltinType::Char32) {
4572      bool FromIsSigned = BT->getKind() == BuiltinType::WChar_S;
4573      uint64_t FromSize = getTypeSize(BT);
4574      QualType PromoteTypes[] = { IntTy, UnsignedIntTy, LongTy, UnsignedLongTy,
4575                                  LongLongTy, UnsignedLongLongTy };
4576      for (size_t Idx = 0; Idx < llvm::array_lengthof(PromoteTypes); ++Idx) {
4577        uint64_t ToSize = getTypeSize(PromoteTypes[Idx]);
4578        if (FromSize < ToSize ||
4579            (FromSize == ToSize &&
4580             FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType()))
4581          return PromoteTypes[Idx];
4582      }
4583      llvm_unreachable("char type should fit into long long");
4584    }
4585  }
4586
4587  // At this point, we should have a signed or unsigned integer type.
4588  if (Promotable->isSignedIntegerType())
4589    return IntTy;
4590  uint64_t PromotableSize = getIntWidth(Promotable);
4591  uint64_t IntSize = getIntWidth(IntTy);
4592  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
4593  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
4594}
4595
4596/// \brief Recurses in pointer/array types until it finds an objc retainable
4597/// type and returns its ownership.
4598Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
4599  while (!T.isNull()) {
4600    if (T.getObjCLifetime() != Qualifiers::OCL_None)
4601      return T.getObjCLifetime();
4602    if (T->isArrayType())
4603      T = getBaseElementType(T);
4604    else if (const PointerType *PT = T->getAs<PointerType>())
4605      T = PT->getPointeeType();
4606    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4607      T = RT->getPointeeType();
4608    else
4609      break;
4610  }
4611
4612  return Qualifiers::OCL_None;
4613}
4614
4615static const Type *getIntegerTypeForEnum(const EnumType *ET) {
4616  // Incomplete enum types are not treated as integer types.
4617  // FIXME: In C++, enum types are never integer types.
4618  if (ET->getDecl()->isComplete() && !ET->getDecl()->isScoped())
4619    return ET->getDecl()->getIntegerType().getTypePtr();
4620  return nullptr;
4621}
4622
4623/// getIntegerTypeOrder - Returns the highest ranked integer type:
4624/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
4625/// LHS < RHS, return -1.
4626int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
4627  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
4628  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
4629
4630  // Unwrap enums to their underlying type.
4631  if (const EnumType *ET = dyn_cast<EnumType>(LHSC))
4632    LHSC = getIntegerTypeForEnum(ET);
4633  if (const EnumType *ET = dyn_cast<EnumType>(RHSC))
4634    RHSC = getIntegerTypeForEnum(ET);
4635
4636  if (LHSC == RHSC) return 0;
4637
4638  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
4639  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
4640
4641  unsigned LHSRank = getIntegerRank(LHSC);
4642  unsigned RHSRank = getIntegerRank(RHSC);
4643
4644  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
4645    if (LHSRank == RHSRank) return 0;
4646    return LHSRank > RHSRank ? 1 : -1;
4647  }
4648
4649  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
4650  if (LHSUnsigned) {
4651    // If the unsigned [LHS] type is larger, return it.
4652    if (LHSRank >= RHSRank)
4653      return 1;
4654
4655    // If the signed type can represent all values of the unsigned type, it
4656    // wins.  Because we are dealing with 2's complement and types that are
4657    // powers of two larger than each other, this is always safe.
4658    return -1;
4659  }
4660
4661  // If the unsigned [RHS] type is larger, return it.
4662  if (RHSRank >= LHSRank)
4663    return -1;
4664
4665  // If the signed type can represent all values of the unsigned type, it
4666  // wins.  Because we are dealing with 2's complement and types that are
4667  // powers of two larger than each other, this is always safe.
4668  return 1;
4669}
4670
4671// getCFConstantStringType - Return the type used for constant CFStrings.
4672QualType ASTContext::getCFConstantStringType() const {
4673  if (!CFConstantStringTypeDecl) {
4674    CFConstantStringTypeDecl = buildImplicitRecord("NSConstantString");
4675    CFConstantStringTypeDecl->startDefinition();
4676
4677    QualType FieldTypes[4];
4678
4679    // const int *isa;
4680    FieldTypes[0] = getPointerType(IntTy.withConst());
4681    // int flags;
4682    FieldTypes[1] = IntTy;
4683    // const char *str;
4684    FieldTypes[2] = getPointerType(CharTy.withConst());
4685    // long length;
4686    FieldTypes[3] = LongTy;
4687
4688    // Create fields
4689    for (unsigned i = 0; i < 4; ++i) {
4690      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
4691                                           SourceLocation(),
4692                                           SourceLocation(), nullptr,
4693                                           FieldTypes[i], /*TInfo=*/nullptr,
4694                                           /*BitWidth=*/nullptr,
4695                                           /*Mutable=*/false,
4696                                           ICIS_NoInit);
4697      Field->setAccess(AS_public);
4698      CFConstantStringTypeDecl->addDecl(Field);
4699    }
4700
4701    CFConstantStringTypeDecl->completeDefinition();
4702  }
4703
4704  return getTagDeclType(CFConstantStringTypeDecl);
4705}
4706
4707QualType ASTContext::getObjCSuperType() const {
4708  if (ObjCSuperType.isNull()) {
4709    RecordDecl *ObjCSuperTypeDecl = buildImplicitRecord("objc_super");
4710    TUDecl->addDecl(ObjCSuperTypeDecl);
4711    ObjCSuperType = getTagDeclType(ObjCSuperTypeDecl);
4712  }
4713  return ObjCSuperType;
4714}
4715
4716void ASTContext::setCFConstantStringType(QualType T) {
4717  const RecordType *Rec = T->getAs<RecordType>();
4718  assert(Rec && "Invalid CFConstantStringType");
4719  CFConstantStringTypeDecl = Rec->getDecl();
4720}
4721
4722QualType ASTContext::getBlockDescriptorType() const {
4723  if (BlockDescriptorType)
4724    return getTagDeclType(BlockDescriptorType);
4725
4726  RecordDecl *RD;
4727  // FIXME: Needs the FlagAppleBlock bit.
4728  RD = buildImplicitRecord("__block_descriptor");
4729  RD->startDefinition();
4730
4731  QualType FieldTypes[] = {
4732    UnsignedLongTy,
4733    UnsignedLongTy,
4734  };
4735
4736  static const char *const FieldNames[] = {
4737    "reserved",
4738    "Size"
4739  };
4740
4741  for (size_t i = 0; i < 2; ++i) {
4742    FieldDecl *Field = FieldDecl::Create(
4743        *this, RD, SourceLocation(), SourceLocation(),
4744        &Idents.get(FieldNames[i]), FieldTypes[i], /*TInfo=*/nullptr,
4745        /*BitWidth=*/nullptr, /*Mutable=*/false, ICIS_NoInit);
4746    Field->setAccess(AS_public);
4747    RD->addDecl(Field);
4748  }
4749
4750  RD->completeDefinition();
4751
4752  BlockDescriptorType = RD;
4753
4754  return getTagDeclType(BlockDescriptorType);
4755}
4756
4757QualType ASTContext::getBlockDescriptorExtendedType() const {
4758  if (BlockDescriptorExtendedType)
4759    return getTagDeclType(BlockDescriptorExtendedType);
4760
4761  RecordDecl *RD;
4762  // FIXME: Needs the FlagAppleBlock bit.
4763  RD = buildImplicitRecord("__block_descriptor_withcopydispose");
4764  RD->startDefinition();
4765
4766  QualType FieldTypes[] = {
4767    UnsignedLongTy,
4768    UnsignedLongTy,
4769    getPointerType(VoidPtrTy),
4770    getPointerType(VoidPtrTy)
4771  };
4772
4773  static const char *const FieldNames[] = {
4774    "reserved",
4775    "Size",
4776    "CopyFuncPtr",
4777    "DestroyFuncPtr"
4778  };
4779
4780  for (size_t i = 0; i < 4; ++i) {
4781    FieldDecl *Field = FieldDecl::Create(
4782        *this, RD, SourceLocation(), SourceLocation(),
4783        &Idents.get(FieldNames[i]), FieldTypes[i], /*TInfo=*/nullptr,
4784        /*BitWidth=*/nullptr,
4785        /*Mutable=*/false, ICIS_NoInit);
4786    Field->setAccess(AS_public);
4787    RD->addDecl(Field);
4788  }
4789
4790  RD->completeDefinition();
4791
4792  BlockDescriptorExtendedType = RD;
4793  return getTagDeclType(BlockDescriptorExtendedType);
4794}
4795
4796/// BlockRequiresCopying - Returns true if byref variable "D" of type "Ty"
4797/// requires copy/dispose. Note that this must match the logic
4798/// in buildByrefHelpers.
4799bool ASTContext::BlockRequiresCopying(QualType Ty,
4800                                      const VarDecl *D) {
4801  if (const CXXRecordDecl *record = Ty->getAsCXXRecordDecl()) {
4802    const Expr *copyExpr = getBlockVarCopyInits(D);
4803    if (!copyExpr && record->hasTrivialDestructor()) return false;
4804
4805    return true;
4806  }
4807
4808  if (!Ty->isObjCRetainableType()) return false;
4809
4810  Qualifiers qs = Ty.getQualifiers();
4811
4812  // If we have lifetime, that dominates.
4813  if (Qualifiers::ObjCLifetime lifetime = qs.getObjCLifetime()) {
4814    assert(getLangOpts().ObjCAutoRefCount);
4815
4816    switch (lifetime) {
4817      case Qualifiers::OCL_None: llvm_unreachable("impossible");
4818
4819      // These are just bits as far as the runtime is concerned.
4820      case Qualifiers::OCL_ExplicitNone:
4821      case Qualifiers::OCL_Autoreleasing:
4822        return false;
4823
4824      // Tell the runtime that this is ARC __weak, called by the
4825      // byref routines.
4826      case Qualifiers::OCL_Weak:
4827      // ARC __strong __block variables need to be retained.
4828      case Qualifiers::OCL_Strong:
4829        return true;
4830    }
4831    llvm_unreachable("fell out of lifetime switch!");
4832  }
4833  return (Ty->isBlockPointerType() || isObjCNSObjectType(Ty) ||
4834          Ty->isObjCObjectPointerType());
4835}
4836
4837bool ASTContext::getByrefLifetime(QualType Ty,
4838                              Qualifiers::ObjCLifetime &LifeTime,
4839                              bool &HasByrefExtendedLayout) const {
4840
4841  if (!getLangOpts().ObjC1 ||
4842      getLangOpts().getGC() != LangOptions::NonGC)
4843    return false;
4844
4845  HasByrefExtendedLayout = false;
4846  if (Ty->isRecordType()) {
4847    HasByrefExtendedLayout = true;
4848    LifeTime = Qualifiers::OCL_None;
4849  }
4850  else if (getLangOpts().ObjCAutoRefCount)
4851    LifeTime = Ty.getObjCLifetime();
4852  // MRR.
4853  else if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4854    LifeTime = Qualifiers::OCL_ExplicitNone;
4855  else
4856    LifeTime = Qualifiers::OCL_None;
4857  return true;
4858}
4859
4860TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
4861  if (!ObjCInstanceTypeDecl)
4862    ObjCInstanceTypeDecl =
4863        buildImplicitTypedef(getObjCIdType(), "instancetype");
4864  return ObjCInstanceTypeDecl;
4865}
4866
4867// This returns true if a type has been typedefed to BOOL:
4868// typedef <type> BOOL;
4869static bool isTypeTypedefedAsBOOL(QualType T) {
4870  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
4871    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
4872      return II->isStr("BOOL");
4873
4874  return false;
4875}
4876
4877/// getObjCEncodingTypeSize returns size of type for objective-c encoding
4878/// purpose.
4879CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
4880  if (!type->isIncompleteArrayType() && type->isIncompleteType())
4881    return CharUnits::Zero();
4882
4883  CharUnits sz = getTypeSizeInChars(type);
4884
4885  // Make all integer and enum types at least as large as an int
4886  if (sz.isPositive() && type->isIntegralOrEnumerationType())
4887    sz = std::max(sz, getTypeSizeInChars(IntTy));
4888  // Treat arrays as pointers, since that's how they're passed in.
4889  else if (type->isArrayType())
4890    sz = getTypeSizeInChars(VoidPtrTy);
4891  return sz;
4892}
4893
4894bool ASTContext::isMSStaticDataMemberInlineDefinition(const VarDecl *VD) const {
4895  return getLangOpts().MSVCCompat && VD->isStaticDataMember() &&
4896         VD->getType()->isIntegralOrEnumerationType() &&
4897         !VD->getFirstDecl()->isOutOfLine() && VD->getFirstDecl()->hasInit();
4898}
4899
4900static inline
4901std::string charUnitsToString(const CharUnits &CU) {
4902  return llvm::itostr(CU.getQuantity());
4903}
4904
4905/// getObjCEncodingForBlock - Return the encoded type for this block
4906/// declaration.
4907std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
4908  std::string S;
4909
4910  const BlockDecl *Decl = Expr->getBlockDecl();
4911  QualType BlockTy =
4912      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
4913  // Encode result type.
4914  if (getLangOpts().EncodeExtendedBlockSig)
4915    getObjCEncodingForMethodParameter(
4916        Decl::OBJC_TQ_None, BlockTy->getAs<FunctionType>()->getReturnType(), S,
4917        true /*Extended*/);
4918  else
4919    getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getReturnType(), S);
4920  // Compute size of all parameters.
4921  // Start with computing size of a pointer in number of bytes.
4922  // FIXME: There might(should) be a better way of doing this computation!
4923  SourceLocation Loc;
4924  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4925  CharUnits ParmOffset = PtrSize;
4926  for (auto PI : Decl->params()) {
4927    QualType PType = PI->getType();
4928    CharUnits sz = getObjCEncodingTypeSize(PType);
4929    if (sz.isZero())
4930      continue;
4931    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
4932    ParmOffset += sz;
4933  }
4934  // Size of the argument frame
4935  S += charUnitsToString(ParmOffset);
4936  // Block pointer and offset.
4937  S += "@?0";
4938
4939  // Argument types.
4940  ParmOffset = PtrSize;
4941  for (auto PVDecl : Decl->params()) {
4942    QualType PType = PVDecl->getOriginalType();
4943    if (const ArrayType *AT =
4944          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4945      // Use array's original type only if it has known number of
4946      // elements.
4947      if (!isa<ConstantArrayType>(AT))
4948        PType = PVDecl->getType();
4949    } else if (PType->isFunctionType())
4950      PType = PVDecl->getType();
4951    if (getLangOpts().EncodeExtendedBlockSig)
4952      getObjCEncodingForMethodParameter(Decl::OBJC_TQ_None, PType,
4953                                      S, true /*Extended*/);
4954    else
4955      getObjCEncodingForType(PType, S);
4956    S += charUnitsToString(ParmOffset);
4957    ParmOffset += getObjCEncodingTypeSize(PType);
4958  }
4959
4960  return S;
4961}
4962
4963bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
4964                                                std::string& S) {
4965  // Encode result type.
4966  getObjCEncodingForType(Decl->getReturnType(), S);
4967  CharUnits ParmOffset;
4968  // Compute size of all parameters.
4969  for (auto PI : Decl->params()) {
4970    QualType PType = PI->getType();
4971    CharUnits sz = getObjCEncodingTypeSize(PType);
4972    if (sz.isZero())
4973      continue;
4974
4975    assert (sz.isPositive() &&
4976        "getObjCEncodingForFunctionDecl - Incomplete param type");
4977    ParmOffset += sz;
4978  }
4979  S += charUnitsToString(ParmOffset);
4980  ParmOffset = CharUnits::Zero();
4981
4982  // Argument types.
4983  for (auto PVDecl : Decl->params()) {
4984    QualType PType = PVDecl->getOriginalType();
4985    if (const ArrayType *AT =
4986          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4987      // Use array's original type only if it has known number of
4988      // elements.
4989      if (!isa<ConstantArrayType>(AT))
4990        PType = PVDecl->getType();
4991    } else if (PType->isFunctionType())
4992      PType = PVDecl->getType();
4993    getObjCEncodingForType(PType, S);
4994    S += charUnitsToString(ParmOffset);
4995    ParmOffset += getObjCEncodingTypeSize(PType);
4996  }
4997
4998  return false;
4999}
5000
5001/// getObjCEncodingForMethodParameter - Return the encoded type for a single
5002/// method parameter or return type. If Extended, include class names and
5003/// block object types.
5004void ASTContext::getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
5005                                                   QualType T, std::string& S,
5006                                                   bool Extended) const {
5007  // Encode type qualifer, 'in', 'inout', etc. for the parameter.
5008  getObjCEncodingForTypeQualifier(QT, S);
5009  // Encode parameter type.
5010  getObjCEncodingForTypeImpl(T, S, true, true, nullptr,
5011                             true     /*OutermostType*/,
5012                             false    /*EncodingProperty*/,
5013                             false    /*StructField*/,
5014                             Extended /*EncodeBlockParameters*/,
5015                             Extended /*EncodeClassNames*/);
5016}
5017
5018/// getObjCEncodingForMethodDecl - Return the encoded type for this method
5019/// declaration.
5020bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
5021                                              std::string& S,
5022                                              bool Extended) const {
5023  // FIXME: This is not very efficient.
5024  // Encode return type.
5025  getObjCEncodingForMethodParameter(Decl->getObjCDeclQualifier(),
5026                                    Decl->getReturnType(), S, Extended);
5027  // Compute size of all parameters.
5028  // Start with computing size of a pointer in number of bytes.
5029  // FIXME: There might(should) be a better way of doing this computation!
5030  SourceLocation Loc;
5031  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
5032  // The first two arguments (self and _cmd) are pointers; account for
5033  // their size.
5034  CharUnits ParmOffset = 2 * PtrSize;
5035  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
5036       E = Decl->sel_param_end(); PI != E; ++PI) {
5037    QualType PType = (*PI)->getType();
5038    CharUnits sz = getObjCEncodingTypeSize(PType);
5039    if (sz.isZero())
5040      continue;
5041
5042    assert (sz.isPositive() &&
5043        "getObjCEncodingForMethodDecl - Incomplete param type");
5044    ParmOffset += sz;
5045  }
5046  S += charUnitsToString(ParmOffset);
5047  S += "@0:";
5048  S += charUnitsToString(PtrSize);
5049
5050  // Argument types.
5051  ParmOffset = 2 * PtrSize;
5052  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
5053       E = Decl->sel_param_end(); PI != E; ++PI) {
5054    const ParmVarDecl *PVDecl = *PI;
5055    QualType PType = PVDecl->getOriginalType();
5056    if (const ArrayType *AT =
5057          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
5058      // Use array's original type only if it has known number of
5059      // elements.
5060      if (!isa<ConstantArrayType>(AT))
5061        PType = PVDecl->getType();
5062    } else if (PType->isFunctionType())
5063      PType = PVDecl->getType();
5064    getObjCEncodingForMethodParameter(PVDecl->getObjCDeclQualifier(),
5065                                      PType, S, Extended);
5066    S += charUnitsToString(ParmOffset);
5067    ParmOffset += getObjCEncodingTypeSize(PType);
5068  }
5069
5070  return false;
5071}
5072
5073ObjCPropertyImplDecl *
5074ASTContext::getObjCPropertyImplDeclForPropertyDecl(
5075                                      const ObjCPropertyDecl *PD,
5076                                      const Decl *Container) const {
5077  if (!Container)
5078    return nullptr;
5079  if (const ObjCCategoryImplDecl *CID =
5080      dyn_cast<ObjCCategoryImplDecl>(Container)) {
5081    for (auto *PID : CID->property_impls())
5082      if (PID->getPropertyDecl() == PD)
5083        return PID;
5084  } else {
5085    const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
5086    for (auto *PID : OID->property_impls())
5087      if (PID->getPropertyDecl() == PD)
5088        return PID;
5089  }
5090  return nullptr;
5091}
5092
5093/// getObjCEncodingForPropertyDecl - Return the encoded type for this
5094/// property declaration. If non-NULL, Container must be either an
5095/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
5096/// NULL when getting encodings for protocol properties.
5097/// Property attributes are stored as a comma-delimited C string. The simple
5098/// attributes readonly and bycopy are encoded as single characters. The
5099/// parametrized attributes, getter=name, setter=name, and ivar=name, are
5100/// encoded as single characters, followed by an identifier. Property types
5101/// are also encoded as a parametrized attribute. The characters used to encode
5102/// these attributes are defined by the following enumeration:
5103/// @code
5104/// enum PropertyAttributes {
5105/// kPropertyReadOnly = 'R',   // property is read-only.
5106/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
5107/// kPropertyByref = '&',  // property is a reference to the value last assigned
5108/// kPropertyDynamic = 'D',    // property is dynamic
5109/// kPropertyGetter = 'G',     // followed by getter selector name
5110/// kPropertySetter = 'S',     // followed by setter selector name
5111/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
5112/// kPropertyType = 'T'              // followed by old-style type encoding.
5113/// kPropertyWeak = 'W'              // 'weak' property
5114/// kPropertyStrong = 'P'            // property GC'able
5115/// kPropertyNonAtomic = 'N'         // property non-atomic
5116/// };
5117/// @endcode
5118void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
5119                                                const Decl *Container,
5120                                                std::string& S) const {
5121  // Collect information from the property implementation decl(s).
5122  bool Dynamic = false;
5123  ObjCPropertyImplDecl *SynthesizePID = nullptr;
5124
5125  if (ObjCPropertyImplDecl *PropertyImpDecl =
5126      getObjCPropertyImplDeclForPropertyDecl(PD, Container)) {
5127    if (PropertyImpDecl->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
5128      Dynamic = true;
5129    else
5130      SynthesizePID = PropertyImpDecl;
5131  }
5132
5133  // FIXME: This is not very efficient.
5134  S = "T";
5135
5136  // Encode result type.
5137  // GCC has some special rules regarding encoding of properties which
5138  // closely resembles encoding of ivars.
5139  getObjCEncodingForPropertyType(PD->getType(), S);
5140
5141  if (PD->isReadOnly()) {
5142    S += ",R";
5143    if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_copy)
5144      S += ",C";
5145    if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_retain)
5146      S += ",&";
5147    if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_weak)
5148      S += ",W";
5149  } else {
5150    switch (PD->getSetterKind()) {
5151    case ObjCPropertyDecl::Assign: break;
5152    case ObjCPropertyDecl::Copy:   S += ",C"; break;
5153    case ObjCPropertyDecl::Retain: S += ",&"; break;
5154    case ObjCPropertyDecl::Weak:   S += ",W"; break;
5155    }
5156  }
5157
5158  // It really isn't clear at all what this means, since properties
5159  // are "dynamic by default".
5160  if (Dynamic)
5161    S += ",D";
5162
5163  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
5164    S += ",N";
5165
5166  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
5167    S += ",G";
5168    S += PD->getGetterName().getAsString();
5169  }
5170
5171  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
5172    S += ",S";
5173    S += PD->getSetterName().getAsString();
5174  }
5175
5176  if (SynthesizePID) {
5177    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
5178    S += ",V";
5179    S += OID->getNameAsString();
5180  }
5181
5182  // FIXME: OBJCGC: weak & strong
5183}
5184
5185/// getLegacyIntegralTypeEncoding -
5186/// Another legacy compatibility encoding: 32-bit longs are encoded as
5187/// 'l' or 'L' , but not always.  For typedefs, we need to use
5188/// 'i' or 'I' instead if encoding a struct field, or a pointer!
5189///
5190void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
5191  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
5192    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
5193      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
5194        PointeeTy = UnsignedIntTy;
5195      else
5196        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
5197          PointeeTy = IntTy;
5198    }
5199  }
5200}
5201
5202void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
5203                                        const FieldDecl *Field,
5204                                        QualType *NotEncodedT) const {
5205  // We follow the behavior of gcc, expanding structures which are
5206  // directly pointed to, and expanding embedded structures. Note that
5207  // these rules are sufficient to prevent recursive encoding of the
5208  // same type.
5209  getObjCEncodingForTypeImpl(T, S, true, true, Field,
5210                             true /* outermost type */, false, false,
5211                             false, false, false, NotEncodedT);
5212}
5213
5214void ASTContext::getObjCEncodingForPropertyType(QualType T,
5215                                                std::string& S) const {
5216  // Encode result type.
5217  // GCC has some special rules regarding encoding of properties which
5218  // closely resembles encoding of ivars.
5219  getObjCEncodingForTypeImpl(T, S, true, true, nullptr,
5220                             true /* outermost type */,
5221                             true /* encoding property */);
5222}
5223
5224static char getObjCEncodingForPrimitiveKind(const ASTContext *C,
5225                                            BuiltinType::Kind kind) {
5226    switch (kind) {
5227    case BuiltinType::Void:       return 'v';
5228    case BuiltinType::Bool:       return 'B';
5229    case BuiltinType::Char_U:
5230    case BuiltinType::UChar:      return 'C';
5231    case BuiltinType::Char16:
5232    case BuiltinType::UShort:     return 'S';
5233    case BuiltinType::Char32:
5234    case BuiltinType::UInt:       return 'I';
5235    case BuiltinType::ULong:
5236        return C->getTargetInfo().getLongWidth() == 32 ? 'L' : 'Q';
5237    case BuiltinType::UInt128:    return 'T';
5238    case BuiltinType::ULongLong:  return 'Q';
5239    case BuiltinType::Char_S:
5240    case BuiltinType::SChar:      return 'c';
5241    case BuiltinType::Short:      return 's';
5242    case BuiltinType::WChar_S:
5243    case BuiltinType::WChar_U:
5244    case BuiltinType::Int:        return 'i';
5245    case BuiltinType::Long:
5246      return C->getTargetInfo().getLongWidth() == 32 ? 'l' : 'q';
5247    case BuiltinType::LongLong:   return 'q';
5248    case BuiltinType::Int128:     return 't';
5249    case BuiltinType::Float:      return 'f';
5250    case BuiltinType::Double:     return 'd';
5251    case BuiltinType::LongDouble: return 'D';
5252    case BuiltinType::NullPtr:    return '*'; // like char*
5253
5254    case BuiltinType::Half:
5255      // FIXME: potentially need @encodes for these!
5256      return ' ';
5257
5258    case BuiltinType::ObjCId:
5259    case BuiltinType::ObjCClass:
5260    case BuiltinType::ObjCSel:
5261      llvm_unreachable("@encoding ObjC primitive type");
5262
5263    // OpenCL and placeholder types don't need @encodings.
5264    case BuiltinType::OCLImage1d:
5265    case BuiltinType::OCLImage1dArray:
5266    case BuiltinType::OCLImage1dBuffer:
5267    case BuiltinType::OCLImage2d:
5268    case BuiltinType::OCLImage2dArray:
5269    case BuiltinType::OCLImage3d:
5270    case BuiltinType::OCLEvent:
5271    case BuiltinType::OCLSampler:
5272    case BuiltinType::Dependent:
5273#define BUILTIN_TYPE(KIND, ID)
5274#define PLACEHOLDER_TYPE(KIND, ID) \
5275    case BuiltinType::KIND:
5276#include "clang/AST/BuiltinTypes.def"
5277      llvm_unreachable("invalid builtin type for @encode");
5278    }
5279    llvm_unreachable("invalid BuiltinType::Kind value");
5280}
5281
5282static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
5283  EnumDecl *Enum = ET->getDecl();
5284
5285  // The encoding of an non-fixed enum type is always 'i', regardless of size.
5286  if (!Enum->isFixed())
5287    return 'i';
5288
5289  // The encoding of a fixed enum type matches its fixed underlying type.
5290  const BuiltinType *BT = Enum->getIntegerType()->castAs<BuiltinType>();
5291  return getObjCEncodingForPrimitiveKind(C, BT->getKind());
5292}
5293
5294static void EncodeBitField(const ASTContext *Ctx, std::string& S,
5295                           QualType T, const FieldDecl *FD) {
5296  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
5297  S += 'b';
5298  // The NeXT runtime encodes bit fields as b followed by the number of bits.
5299  // The GNU runtime requires more information; bitfields are encoded as b,
5300  // then the offset (in bits) of the first element, then the type of the
5301  // bitfield, then the size in bits.  For example, in this structure:
5302  //
5303  // struct
5304  // {
5305  //    int integer;
5306  //    int flags:2;
5307  // };
5308  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
5309  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
5310  // information is not especially sensible, but we're stuck with it for
5311  // compatibility with GCC, although providing it breaks anything that
5312  // actually uses runtime introspection and wants to work on both runtimes...
5313  if (Ctx->getLangOpts().ObjCRuntime.isGNUFamily()) {
5314    const RecordDecl *RD = FD->getParent();
5315    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
5316    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
5317    if (const EnumType *ET = T->getAs<EnumType>())
5318      S += ObjCEncodingForEnumType(Ctx, ET);
5319    else {
5320      const BuiltinType *BT = T->castAs<BuiltinType>();
5321      S += getObjCEncodingForPrimitiveKind(Ctx, BT->getKind());
5322    }
5323  }
5324  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
5325}
5326
5327// FIXME: Use SmallString for accumulating string.
5328void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
5329                                            bool ExpandPointedToStructures,
5330                                            bool ExpandStructures,
5331                                            const FieldDecl *FD,
5332                                            bool OutermostType,
5333                                            bool EncodingProperty,
5334                                            bool StructField,
5335                                            bool EncodeBlockParameters,
5336                                            bool EncodeClassNames,
5337                                            bool EncodePointerToObjCTypedef,
5338                                            QualType *NotEncodedT) const {
5339  CanQualType CT = getCanonicalType(T);
5340  switch (CT->getTypeClass()) {
5341  case Type::Builtin:
5342  case Type::Enum:
5343    if (FD && FD->isBitField())
5344      return EncodeBitField(this, S, T, FD);
5345    if (const BuiltinType *BT = dyn_cast<BuiltinType>(CT))
5346      S += getObjCEncodingForPrimitiveKind(this, BT->getKind());
5347    else
5348      S += ObjCEncodingForEnumType(this, cast<EnumType>(CT));
5349    return;
5350
5351  case Type::Complex: {
5352    const ComplexType *CT = T->castAs<ComplexType>();
5353    S += 'j';
5354    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, nullptr);
5355    return;
5356  }
5357
5358  case Type::Atomic: {
5359    const AtomicType *AT = T->castAs<AtomicType>();
5360    S += 'A';
5361    getObjCEncodingForTypeImpl(AT->getValueType(), S, false, false, nullptr);
5362    return;
5363  }
5364
5365  // encoding for pointer or reference types.
5366  case Type::Pointer:
5367  case Type::LValueReference:
5368  case Type::RValueReference: {
5369    QualType PointeeTy;
5370    if (isa<PointerType>(CT)) {
5371      const PointerType *PT = T->castAs<PointerType>();
5372      if (PT->isObjCSelType()) {
5373        S += ':';
5374        return;
5375      }
5376      PointeeTy = PT->getPointeeType();
5377    } else {
5378      PointeeTy = T->castAs<ReferenceType>()->getPointeeType();
5379    }
5380
5381    bool isReadOnly = false;
5382    // For historical/compatibility reasons, the read-only qualifier of the
5383    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
5384    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
5385    // Also, do not emit the 'r' for anything but the outermost type!
5386    if (isa<TypedefType>(T.getTypePtr())) {
5387      if (OutermostType && T.isConstQualified()) {
5388        isReadOnly = true;
5389        S += 'r';
5390      }
5391    } else if (OutermostType) {
5392      QualType P = PointeeTy;
5393      while (P->getAs<PointerType>())
5394        P = P->getAs<PointerType>()->getPointeeType();
5395      if (P.isConstQualified()) {
5396        isReadOnly = true;
5397        S += 'r';
5398      }
5399    }
5400    if (isReadOnly) {
5401      // Another legacy compatibility encoding. Some ObjC qualifier and type
5402      // combinations need to be rearranged.
5403      // Rewrite "in const" from "nr" to "rn"
5404      if (StringRef(S).endswith("nr"))
5405        S.replace(S.end()-2, S.end(), "rn");
5406    }
5407
5408    if (PointeeTy->isCharType()) {
5409      // char pointer types should be encoded as '*' unless it is a
5410      // type that has been typedef'd to 'BOOL'.
5411      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
5412        S += '*';
5413        return;
5414      }
5415    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
5416      // GCC binary compat: Need to convert "struct objc_class *" to "#".
5417      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
5418        S += '#';
5419        return;
5420      }
5421      // GCC binary compat: Need to convert "struct objc_object *" to "@".
5422      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
5423        S += '@';
5424        return;
5425      }
5426      // fall through...
5427    }
5428    S += '^';
5429    getLegacyIntegralTypeEncoding(PointeeTy);
5430
5431    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
5432                               nullptr, false, false, false, false, false, false,
5433                               NotEncodedT);
5434    return;
5435  }
5436
5437  case Type::ConstantArray:
5438  case Type::IncompleteArray:
5439  case Type::VariableArray: {
5440    const ArrayType *AT = cast<ArrayType>(CT);
5441
5442    if (isa<IncompleteArrayType>(AT) && !StructField) {
5443      // Incomplete arrays are encoded as a pointer to the array element.
5444      S += '^';
5445
5446      getObjCEncodingForTypeImpl(AT->getElementType(), S,
5447                                 false, ExpandStructures, FD);
5448    } else {
5449      S += '[';
5450
5451      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
5452        S += llvm::utostr(CAT->getSize().getZExtValue());
5453      else {
5454        //Variable length arrays are encoded as a regular array with 0 elements.
5455        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
5456               "Unknown array type!");
5457        S += '0';
5458      }
5459
5460      getObjCEncodingForTypeImpl(AT->getElementType(), S,
5461                                 false, ExpandStructures, FD,
5462                                 false, false, false, false, false, false,
5463                                 NotEncodedT);
5464      S += ']';
5465    }
5466    return;
5467  }
5468
5469  case Type::FunctionNoProto:
5470  case Type::FunctionProto:
5471    S += '?';
5472    return;
5473
5474  case Type::Record: {
5475    RecordDecl *RDecl = cast<RecordType>(CT)->getDecl();
5476    S += RDecl->isUnion() ? '(' : '{';
5477    // Anonymous structures print as '?'
5478    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
5479      S += II->getName();
5480      if (ClassTemplateSpecializationDecl *Spec
5481          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
5482        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
5483        llvm::raw_string_ostream OS(S);
5484        TemplateSpecializationType::PrintTemplateArgumentList(OS,
5485                                            TemplateArgs.data(),
5486                                            TemplateArgs.size(),
5487                                            (*this).getPrintingPolicy());
5488      }
5489    } else {
5490      S += '?';
5491    }
5492    if (ExpandStructures) {
5493      S += '=';
5494      if (!RDecl->isUnion()) {
5495        getObjCEncodingForStructureImpl(RDecl, S, FD, true, NotEncodedT);
5496      } else {
5497        for (const auto *Field : RDecl->fields()) {
5498          if (FD) {
5499            S += '"';
5500            S += Field->getNameAsString();
5501            S += '"';
5502          }
5503
5504          // Special case bit-fields.
5505          if (Field->isBitField()) {
5506            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
5507                                       Field);
5508          } else {
5509            QualType qt = Field->getType();
5510            getLegacyIntegralTypeEncoding(qt);
5511            getObjCEncodingForTypeImpl(qt, S, false, true,
5512                                       FD, /*OutermostType*/false,
5513                                       /*EncodingProperty*/false,
5514                                       /*StructField*/true,
5515                                       false, false, false, NotEncodedT);
5516          }
5517        }
5518      }
5519    }
5520    S += RDecl->isUnion() ? ')' : '}';
5521    return;
5522  }
5523
5524  case Type::BlockPointer: {
5525    const BlockPointerType *BT = T->castAs<BlockPointerType>();
5526    S += "@?"; // Unlike a pointer-to-function, which is "^?".
5527    if (EncodeBlockParameters) {
5528      const FunctionType *FT = BT->getPointeeType()->castAs<FunctionType>();
5529
5530      S += '<';
5531      // Block return type
5532      getObjCEncodingForTypeImpl(
5533          FT->getReturnType(), S, ExpandPointedToStructures, ExpandStructures,
5534          FD, false /* OutermostType */, EncodingProperty,
5535          false /* StructField */, EncodeBlockParameters, EncodeClassNames, false,
5536                                 NotEncodedT);
5537      // Block self
5538      S += "@?";
5539      // Block parameters
5540      if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT)) {
5541        for (const auto &I : FPT->param_types())
5542          getObjCEncodingForTypeImpl(
5543              I, S, ExpandPointedToStructures, ExpandStructures, FD,
5544              false /* OutermostType */, EncodingProperty,
5545              false /* StructField */, EncodeBlockParameters, EncodeClassNames,
5546                                     false, NotEncodedT);
5547      }
5548      S += '>';
5549    }
5550    return;
5551  }
5552
5553  case Type::ObjCObject: {
5554    // hack to match legacy encoding of *id and *Class
5555    QualType Ty = getObjCObjectPointerType(CT);
5556    if (Ty->isObjCIdType()) {
5557      S += "{objc_object=}";
5558      return;
5559    }
5560    else if (Ty->isObjCClassType()) {
5561      S += "{objc_class=}";
5562      return;
5563    }
5564  }
5565
5566  case Type::ObjCInterface: {
5567    // Ignore protocol qualifiers when mangling at this level.
5568    T = T->castAs<ObjCObjectType>()->getBaseType();
5569
5570    // The assumption seems to be that this assert will succeed
5571    // because nested levels will have filtered out 'id' and 'Class'.
5572    const ObjCInterfaceType *OIT = T->castAs<ObjCInterfaceType>();
5573    // @encode(class_name)
5574    ObjCInterfaceDecl *OI = OIT->getDecl();
5575    S += '{';
5576    const IdentifierInfo *II = OI->getIdentifier();
5577    S += II->getName();
5578    S += '=';
5579    SmallVector<const ObjCIvarDecl*, 32> Ivars;
5580    DeepCollectObjCIvars(OI, true, Ivars);
5581    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
5582      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
5583      if (Field->isBitField())
5584        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
5585      else
5586        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD,
5587                                   false, false, false, false, false,
5588                                   EncodePointerToObjCTypedef,
5589                                   NotEncodedT);
5590    }
5591    S += '}';
5592    return;
5593  }
5594
5595  case Type::ObjCObjectPointer: {
5596    const ObjCObjectPointerType *OPT = T->castAs<ObjCObjectPointerType>();
5597    if (OPT->isObjCIdType()) {
5598      S += '@';
5599      return;
5600    }
5601
5602    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
5603      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
5604      // Since this is a binary compatibility issue, need to consult with runtime
5605      // folks. Fortunately, this is a *very* obsure construct.
5606      S += '#';
5607      return;
5608    }
5609
5610    if (OPT->isObjCQualifiedIdType()) {
5611      getObjCEncodingForTypeImpl(getObjCIdType(), S,
5612                                 ExpandPointedToStructures,
5613                                 ExpandStructures, FD);
5614      if (FD || EncodingProperty || EncodeClassNames) {
5615        // Note that we do extended encoding of protocol qualifer list
5616        // Only when doing ivar or property encoding.
5617        S += '"';
5618        for (const auto *I : OPT->quals()) {
5619          S += '<';
5620          S += I->getNameAsString();
5621          S += '>';
5622        }
5623        S += '"';
5624      }
5625      return;
5626    }
5627
5628    QualType PointeeTy = OPT->getPointeeType();
5629    if (!EncodingProperty &&
5630        isa<TypedefType>(PointeeTy.getTypePtr()) &&
5631        !EncodePointerToObjCTypedef) {
5632      // Another historical/compatibility reason.
5633      // We encode the underlying type which comes out as
5634      // {...};
5635      S += '^';
5636      if (FD && OPT->getInterfaceDecl()) {
5637        // Prevent recursive encoding of fields in some rare cases.
5638        ObjCInterfaceDecl *OI = OPT->getInterfaceDecl();
5639        SmallVector<const ObjCIvarDecl*, 32> Ivars;
5640        DeepCollectObjCIvars(OI, true, Ivars);
5641        for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
5642          if (cast<FieldDecl>(Ivars[i]) == FD) {
5643            S += '{';
5644            S += OI->getIdentifier()->getName();
5645            S += '}';
5646            return;
5647          }
5648        }
5649      }
5650      getObjCEncodingForTypeImpl(PointeeTy, S,
5651                                 false, ExpandPointedToStructures,
5652                                 nullptr,
5653                                 false, false, false, false, false,
5654                                 /*EncodePointerToObjCTypedef*/true);
5655      return;
5656    }
5657
5658    S += '@';
5659    if (OPT->getInterfaceDecl() &&
5660        (FD || EncodingProperty || EncodeClassNames)) {
5661      S += '"';
5662      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
5663      for (const auto *I : OPT->quals()) {
5664        S += '<';
5665        S += I->getNameAsString();
5666        S += '>';
5667      }
5668      S += '"';
5669    }
5670    return;
5671  }
5672
5673  // gcc just blithely ignores member pointers.
5674  // FIXME: we shoul do better than that.  'M' is available.
5675  case Type::MemberPointer:
5676  // This matches gcc's encoding, even though technically it is insufficient.
5677  //FIXME. We should do a better job than gcc.
5678  case Type::Vector:
5679  case Type::ExtVector:
5680  // Until we have a coherent encoding of these three types, issue warning.
5681    { if (NotEncodedT)
5682        *NotEncodedT = T;
5683      return;
5684    }
5685
5686  // We could see an undeduced auto type here during error recovery.
5687  // Just ignore it.
5688  case Type::Auto:
5689    return;
5690
5691
5692#define ABSTRACT_TYPE(KIND, BASE)
5693#define TYPE(KIND, BASE)
5694#define DEPENDENT_TYPE(KIND, BASE) \
5695  case Type::KIND:
5696#define NON_CANONICAL_TYPE(KIND, BASE) \
5697  case Type::KIND:
5698#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(KIND, BASE) \
5699  case Type::KIND:
5700#include "clang/AST/TypeNodes.def"
5701    llvm_unreachable("@encode for dependent type!");
5702  }
5703  llvm_unreachable("bad type kind!");
5704}
5705
5706void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
5707                                                 std::string &S,
5708                                                 const FieldDecl *FD,
5709                                                 bool includeVBases,
5710                                                 QualType *NotEncodedT) const {
5711  assert(RDecl && "Expected non-null RecordDecl");
5712  assert(!RDecl->isUnion() && "Should not be called for unions");
5713  if (!RDecl->getDefinition())
5714    return;
5715
5716  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
5717  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
5718  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
5719
5720  if (CXXRec) {
5721    for (const auto &BI : CXXRec->bases()) {
5722      if (!BI.isVirtual()) {
5723        CXXRecordDecl *base = BI.getType()->getAsCXXRecordDecl();
5724        if (base->isEmpty())
5725          continue;
5726        uint64_t offs = toBits(layout.getBaseClassOffset(base));
5727        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5728                                  std::make_pair(offs, base));
5729      }
5730    }
5731  }
5732
5733  unsigned i = 0;
5734  for (auto *Field : RDecl->fields()) {
5735    uint64_t offs = layout.getFieldOffset(i);
5736    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5737                              std::make_pair(offs, Field));
5738    ++i;
5739  }
5740
5741  if (CXXRec && includeVBases) {
5742    for (const auto &BI : CXXRec->vbases()) {
5743      CXXRecordDecl *base = BI.getType()->getAsCXXRecordDecl();
5744      if (base->isEmpty())
5745        continue;
5746      uint64_t offs = toBits(layout.getVBaseClassOffset(base));
5747      if (offs >= uint64_t(toBits(layout.getNonVirtualSize())) &&
5748          FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
5749        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
5750                                  std::make_pair(offs, base));
5751    }
5752  }
5753
5754  CharUnits size;
5755  if (CXXRec) {
5756    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
5757  } else {
5758    size = layout.getSize();
5759  }
5760
5761#ifndef NDEBUG
5762  uint64_t CurOffs = 0;
5763#endif
5764  std::multimap<uint64_t, NamedDecl *>::iterator
5765    CurLayObj = FieldOrBaseOffsets.begin();
5766
5767  if (CXXRec && CXXRec->isDynamicClass() &&
5768      (CurLayObj == FieldOrBaseOffsets.end() || CurLayObj->first != 0)) {
5769    if (FD) {
5770      S += "\"_vptr$";
5771      std::string recname = CXXRec->getNameAsString();
5772      if (recname.empty()) recname = "?";
5773      S += recname;
5774      S += '"';
5775    }
5776    S += "^^?";
5777#ifndef NDEBUG
5778    CurOffs += getTypeSize(VoidPtrTy);
5779#endif
5780  }
5781
5782  if (!RDecl->hasFlexibleArrayMember()) {
5783    // Mark the end of the structure.
5784    uint64_t offs = toBits(size);
5785    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5786                              std::make_pair(offs, nullptr));
5787  }
5788
5789  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
5790#ifndef NDEBUG
5791    assert(CurOffs <= CurLayObj->first);
5792    if (CurOffs < CurLayObj->first) {
5793      uint64_t padding = CurLayObj->first - CurOffs;
5794      // FIXME: There doesn't seem to be a way to indicate in the encoding that
5795      // packing/alignment of members is different that normal, in which case
5796      // the encoding will be out-of-sync with the real layout.
5797      // If the runtime switches to just consider the size of types without
5798      // taking into account alignment, we could make padding explicit in the
5799      // encoding (e.g. using arrays of chars). The encoding strings would be
5800      // longer then though.
5801      CurOffs += padding;
5802    }
5803#endif
5804
5805    NamedDecl *dcl = CurLayObj->second;
5806    if (!dcl)
5807      break; // reached end of structure.
5808
5809    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
5810      // We expand the bases without their virtual bases since those are going
5811      // in the initial structure. Note that this differs from gcc which
5812      // expands virtual bases each time one is encountered in the hierarchy,
5813      // making the encoding type bigger than it really is.
5814      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false,
5815                                      NotEncodedT);
5816      assert(!base->isEmpty());
5817#ifndef NDEBUG
5818      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
5819#endif
5820    } else {
5821      FieldDecl *field = cast<FieldDecl>(dcl);
5822      if (FD) {
5823        S += '"';
5824        S += field->getNameAsString();
5825        S += '"';
5826      }
5827
5828      if (field->isBitField()) {
5829        EncodeBitField(this, S, field->getType(), field);
5830#ifndef NDEBUG
5831        CurOffs += field->getBitWidthValue(*this);
5832#endif
5833      } else {
5834        QualType qt = field->getType();
5835        getLegacyIntegralTypeEncoding(qt);
5836        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
5837                                   /*OutermostType*/false,
5838                                   /*EncodingProperty*/false,
5839                                   /*StructField*/true,
5840                                   false, false, false, NotEncodedT);
5841#ifndef NDEBUG
5842        CurOffs += getTypeSize(field->getType());
5843#endif
5844      }
5845    }
5846  }
5847}
5848
5849void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
5850                                                 std::string& S) const {
5851  if (QT & Decl::OBJC_TQ_In)
5852    S += 'n';
5853  if (QT & Decl::OBJC_TQ_Inout)
5854    S += 'N';
5855  if (QT & Decl::OBJC_TQ_Out)
5856    S += 'o';
5857  if (QT & Decl::OBJC_TQ_Bycopy)
5858    S += 'O';
5859  if (QT & Decl::OBJC_TQ_Byref)
5860    S += 'R';
5861  if (QT & Decl::OBJC_TQ_Oneway)
5862    S += 'V';
5863}
5864
5865TypedefDecl *ASTContext::getObjCIdDecl() const {
5866  if (!ObjCIdDecl) {
5867    QualType T = getObjCObjectType(ObjCBuiltinIdTy, nullptr, 0);
5868    T = getObjCObjectPointerType(T);
5869    ObjCIdDecl = buildImplicitTypedef(T, "id");
5870  }
5871  return ObjCIdDecl;
5872}
5873
5874TypedefDecl *ASTContext::getObjCSelDecl() const {
5875  if (!ObjCSelDecl) {
5876    QualType T = getPointerType(ObjCBuiltinSelTy);
5877    ObjCSelDecl = buildImplicitTypedef(T, "SEL");
5878  }
5879  return ObjCSelDecl;
5880}
5881
5882TypedefDecl *ASTContext::getObjCClassDecl() const {
5883  if (!ObjCClassDecl) {
5884    QualType T = getObjCObjectType(ObjCBuiltinClassTy, nullptr, 0);
5885    T = getObjCObjectPointerType(T);
5886    ObjCClassDecl = buildImplicitTypedef(T, "Class");
5887  }
5888  return ObjCClassDecl;
5889}
5890
5891ObjCInterfaceDecl *ASTContext::getObjCProtocolDecl() const {
5892  if (!ObjCProtocolClassDecl) {
5893    ObjCProtocolClassDecl
5894      = ObjCInterfaceDecl::Create(*this, getTranslationUnitDecl(),
5895                                  SourceLocation(),
5896                                  &Idents.get("Protocol"),
5897                                  /*PrevDecl=*/nullptr,
5898                                  SourceLocation(), true);
5899  }
5900
5901  return ObjCProtocolClassDecl;
5902}
5903
5904//===----------------------------------------------------------------------===//
5905// __builtin_va_list Construction Functions
5906//===----------------------------------------------------------------------===//
5907
5908static TypedefDecl *CreateCharPtrBuiltinVaListDecl(const ASTContext *Context) {
5909  // typedef char* __builtin_va_list;
5910  QualType T = Context->getPointerType(Context->CharTy);
5911  return Context->buildImplicitTypedef(T, "__builtin_va_list");
5912}
5913
5914static TypedefDecl *CreateVoidPtrBuiltinVaListDecl(const ASTContext *Context) {
5915  // typedef void* __builtin_va_list;
5916  QualType T = Context->getPointerType(Context->VoidTy);
5917  return Context->buildImplicitTypedef(T, "__builtin_va_list");
5918}
5919
5920static TypedefDecl *
5921CreateAArch64ABIBuiltinVaListDecl(const ASTContext *Context) {
5922  // struct __va_list
5923  RecordDecl *VaListTagDecl = Context->buildImplicitRecord("__va_list");
5924  if (Context->getLangOpts().CPlusPlus) {
5925    // namespace std { struct __va_list {
5926    NamespaceDecl *NS;
5927    NS = NamespaceDecl::Create(const_cast<ASTContext &>(*Context),
5928                               Context->getTranslationUnitDecl(),
5929                               /*Inline*/ false, SourceLocation(),
5930                               SourceLocation(), &Context->Idents.get("std"),
5931                               /*PrevDecl*/ nullptr);
5932    NS->setImplicit();
5933    VaListTagDecl->setDeclContext(NS);
5934  }
5935
5936  VaListTagDecl->startDefinition();
5937
5938  const size_t NumFields = 5;
5939  QualType FieldTypes[NumFields];
5940  const char *FieldNames[NumFields];
5941
5942  // void *__stack;
5943  FieldTypes[0] = Context->getPointerType(Context->VoidTy);
5944  FieldNames[0] = "__stack";
5945
5946  // void *__gr_top;
5947  FieldTypes[1] = Context->getPointerType(Context->VoidTy);
5948  FieldNames[1] = "__gr_top";
5949
5950  // void *__vr_top;
5951  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
5952  FieldNames[2] = "__vr_top";
5953
5954  // int __gr_offs;
5955  FieldTypes[3] = Context->IntTy;
5956  FieldNames[3] = "__gr_offs";
5957
5958  // int __vr_offs;
5959  FieldTypes[4] = Context->IntTy;
5960  FieldNames[4] = "__vr_offs";
5961
5962  // Create fields
5963  for (unsigned i = 0; i < NumFields; ++i) {
5964    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
5965                                         VaListTagDecl,
5966                                         SourceLocation(),
5967                                         SourceLocation(),
5968                                         &Context->Idents.get(FieldNames[i]),
5969                                         FieldTypes[i], /*TInfo=*/nullptr,
5970                                         /*BitWidth=*/nullptr,
5971                                         /*Mutable=*/false,
5972                                         ICIS_NoInit);
5973    Field->setAccess(AS_public);
5974    VaListTagDecl->addDecl(Field);
5975  }
5976  VaListTagDecl->completeDefinition();
5977  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
5978  Context->VaListTagTy = VaListTagType;
5979
5980  // } __builtin_va_list;
5981  return Context->buildImplicitTypedef(VaListTagType, "__builtin_va_list");
5982}
5983
5984static TypedefDecl *CreatePowerABIBuiltinVaListDecl(const ASTContext *Context) {
5985  // typedef struct __va_list_tag {
5986  RecordDecl *VaListTagDecl;
5987
5988  VaListTagDecl = Context->buildImplicitRecord("__va_list_tag");
5989  VaListTagDecl->startDefinition();
5990
5991  const size_t NumFields = 5;
5992  QualType FieldTypes[NumFields];
5993  const char *FieldNames[NumFields];
5994
5995  //   unsigned char gpr;
5996  FieldTypes[0] = Context->UnsignedCharTy;
5997  FieldNames[0] = "gpr";
5998
5999  //   unsigned char fpr;
6000  FieldTypes[1] = Context->UnsignedCharTy;
6001  FieldNames[1] = "fpr";
6002
6003  //   unsigned short reserved;
6004  FieldTypes[2] = Context->UnsignedShortTy;
6005  FieldNames[2] = "reserved";
6006
6007  //   void* overflow_arg_area;
6008  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
6009  FieldNames[3] = "overflow_arg_area";
6010
6011  //   void* reg_save_area;
6012  FieldTypes[4] = Context->getPointerType(Context->VoidTy);
6013  FieldNames[4] = "reg_save_area";
6014
6015  // Create fields
6016  for (unsigned i = 0; i < NumFields; ++i) {
6017    FieldDecl *Field = FieldDecl::Create(*Context, VaListTagDecl,
6018                                         SourceLocation(),
6019                                         SourceLocation(),
6020                                         &Context->Idents.get(FieldNames[i]),
6021                                         FieldTypes[i], /*TInfo=*/nullptr,
6022                                         /*BitWidth=*/nullptr,
6023                                         /*Mutable=*/false,
6024                                         ICIS_NoInit);
6025    Field->setAccess(AS_public);
6026    VaListTagDecl->addDecl(Field);
6027  }
6028  VaListTagDecl->completeDefinition();
6029  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
6030  Context->VaListTagTy = VaListTagType;
6031
6032  // } __va_list_tag;
6033  TypedefDecl *VaListTagTypedefDecl =
6034      Context->buildImplicitTypedef(VaListTagType, "__va_list_tag");
6035
6036  QualType VaListTagTypedefType =
6037    Context->getTypedefType(VaListTagTypedefDecl);
6038
6039  // typedef __va_list_tag __builtin_va_list[1];
6040  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
6041  QualType VaListTagArrayType
6042    = Context->getConstantArrayType(VaListTagTypedefType,
6043                                    Size, ArrayType::Normal, 0);
6044  return Context->buildImplicitTypedef(VaListTagArrayType, "__builtin_va_list");
6045}
6046
6047static TypedefDecl *
6048CreateX86_64ABIBuiltinVaListDecl(const ASTContext *Context) {
6049  // typedef struct __va_list_tag {
6050  RecordDecl *VaListTagDecl;
6051  VaListTagDecl = Context->buildImplicitRecord("__va_list_tag");
6052  VaListTagDecl->startDefinition();
6053
6054  const size_t NumFields = 4;
6055  QualType FieldTypes[NumFields];
6056  const char *FieldNames[NumFields];
6057
6058  //   unsigned gp_offset;
6059  FieldTypes[0] = Context->UnsignedIntTy;
6060  FieldNames[0] = "gp_offset";
6061
6062  //   unsigned fp_offset;
6063  FieldTypes[1] = Context->UnsignedIntTy;
6064  FieldNames[1] = "fp_offset";
6065
6066  //   void* overflow_arg_area;
6067  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
6068  FieldNames[2] = "overflow_arg_area";
6069
6070  //   void* reg_save_area;
6071  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
6072  FieldNames[3] = "reg_save_area";
6073
6074  // Create fields
6075  for (unsigned i = 0; i < NumFields; ++i) {
6076    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6077                                         VaListTagDecl,
6078                                         SourceLocation(),
6079                                         SourceLocation(),
6080                                         &Context->Idents.get(FieldNames[i]),
6081                                         FieldTypes[i], /*TInfo=*/nullptr,
6082                                         /*BitWidth=*/nullptr,
6083                                         /*Mutable=*/false,
6084                                         ICIS_NoInit);
6085    Field->setAccess(AS_public);
6086    VaListTagDecl->addDecl(Field);
6087  }
6088  VaListTagDecl->completeDefinition();
6089  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
6090  Context->VaListTagTy = VaListTagType;
6091
6092  // } __va_list_tag;
6093  TypedefDecl *VaListTagTypedefDecl =
6094      Context->buildImplicitTypedef(VaListTagType, "__va_list_tag");
6095
6096  QualType VaListTagTypedefType =
6097    Context->getTypedefType(VaListTagTypedefDecl);
6098
6099  // typedef __va_list_tag __builtin_va_list[1];
6100  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
6101  QualType VaListTagArrayType
6102    = Context->getConstantArrayType(VaListTagTypedefType,
6103                                      Size, ArrayType::Normal,0);
6104  return Context->buildImplicitTypedef(VaListTagArrayType, "__builtin_va_list");
6105}
6106
6107static TypedefDecl *CreatePNaClABIBuiltinVaListDecl(const ASTContext *Context) {
6108  // typedef int __builtin_va_list[4];
6109  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 4);
6110  QualType IntArrayType
6111    = Context->getConstantArrayType(Context->IntTy,
6112				    Size, ArrayType::Normal, 0);
6113  return Context->buildImplicitTypedef(IntArrayType, "__builtin_va_list");
6114}
6115
6116static TypedefDecl *
6117CreateAAPCSABIBuiltinVaListDecl(const ASTContext *Context) {
6118  // struct __va_list
6119  RecordDecl *VaListDecl = Context->buildImplicitRecord("__va_list");
6120  if (Context->getLangOpts().CPlusPlus) {
6121    // namespace std { struct __va_list {
6122    NamespaceDecl *NS;
6123    NS = NamespaceDecl::Create(const_cast<ASTContext &>(*Context),
6124                               Context->getTranslationUnitDecl(),
6125                               /*Inline*/false, SourceLocation(),
6126                               SourceLocation(), &Context->Idents.get("std"),
6127                               /*PrevDecl*/ nullptr);
6128    NS->setImplicit();
6129    VaListDecl->setDeclContext(NS);
6130  }
6131
6132  VaListDecl->startDefinition();
6133
6134  // void * __ap;
6135  FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6136                                       VaListDecl,
6137                                       SourceLocation(),
6138                                       SourceLocation(),
6139                                       &Context->Idents.get("__ap"),
6140                                       Context->getPointerType(Context->VoidTy),
6141                                       /*TInfo=*/nullptr,
6142                                       /*BitWidth=*/nullptr,
6143                                       /*Mutable=*/false,
6144                                       ICIS_NoInit);
6145  Field->setAccess(AS_public);
6146  VaListDecl->addDecl(Field);
6147
6148  // };
6149  VaListDecl->completeDefinition();
6150
6151  // typedef struct __va_list __builtin_va_list;
6152  QualType T = Context->getRecordType(VaListDecl);
6153  return Context->buildImplicitTypedef(T, "__builtin_va_list");
6154}
6155
6156static TypedefDecl *
6157CreateSystemZBuiltinVaListDecl(const ASTContext *Context) {
6158  // typedef struct __va_list_tag {
6159  RecordDecl *VaListTagDecl;
6160  VaListTagDecl = Context->buildImplicitRecord("__va_list_tag");
6161  VaListTagDecl->startDefinition();
6162
6163  const size_t NumFields = 4;
6164  QualType FieldTypes[NumFields];
6165  const char *FieldNames[NumFields];
6166
6167  //   long __gpr;
6168  FieldTypes[0] = Context->LongTy;
6169  FieldNames[0] = "__gpr";
6170
6171  //   long __fpr;
6172  FieldTypes[1] = Context->LongTy;
6173  FieldNames[1] = "__fpr";
6174
6175  //   void *__overflow_arg_area;
6176  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
6177  FieldNames[2] = "__overflow_arg_area";
6178
6179  //   void *__reg_save_area;
6180  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
6181  FieldNames[3] = "__reg_save_area";
6182
6183  // Create fields
6184  for (unsigned i = 0; i < NumFields; ++i) {
6185    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6186                                         VaListTagDecl,
6187                                         SourceLocation(),
6188                                         SourceLocation(),
6189                                         &Context->Idents.get(FieldNames[i]),
6190                                         FieldTypes[i], /*TInfo=*/nullptr,
6191                                         /*BitWidth=*/nullptr,
6192                                         /*Mutable=*/false,
6193                                         ICIS_NoInit);
6194    Field->setAccess(AS_public);
6195    VaListTagDecl->addDecl(Field);
6196  }
6197  VaListTagDecl->completeDefinition();
6198  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
6199  Context->VaListTagTy = VaListTagType;
6200
6201  // } __va_list_tag;
6202  TypedefDecl *VaListTagTypedefDecl =
6203      Context->buildImplicitTypedef(VaListTagType, "__va_list_tag");
6204  QualType VaListTagTypedefType =
6205    Context->getTypedefType(VaListTagTypedefDecl);
6206
6207  // typedef __va_list_tag __builtin_va_list[1];
6208  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
6209  QualType VaListTagArrayType
6210    = Context->getConstantArrayType(VaListTagTypedefType,
6211                                      Size, ArrayType::Normal,0);
6212
6213  return Context->buildImplicitTypedef(VaListTagArrayType, "__builtin_va_list");
6214}
6215
6216static TypedefDecl *CreateVaListDecl(const ASTContext *Context,
6217                                     TargetInfo::BuiltinVaListKind Kind) {
6218  switch (Kind) {
6219  case TargetInfo::CharPtrBuiltinVaList:
6220    return CreateCharPtrBuiltinVaListDecl(Context);
6221  case TargetInfo::VoidPtrBuiltinVaList:
6222    return CreateVoidPtrBuiltinVaListDecl(Context);
6223  case TargetInfo::AArch64ABIBuiltinVaList:
6224    return CreateAArch64ABIBuiltinVaListDecl(Context);
6225  case TargetInfo::PowerABIBuiltinVaList:
6226    return CreatePowerABIBuiltinVaListDecl(Context);
6227  case TargetInfo::X86_64ABIBuiltinVaList:
6228    return CreateX86_64ABIBuiltinVaListDecl(Context);
6229  case TargetInfo::PNaClABIBuiltinVaList:
6230    return CreatePNaClABIBuiltinVaListDecl(Context);
6231  case TargetInfo::AAPCSABIBuiltinVaList:
6232    return CreateAAPCSABIBuiltinVaListDecl(Context);
6233  case TargetInfo::SystemZBuiltinVaList:
6234    return CreateSystemZBuiltinVaListDecl(Context);
6235  }
6236
6237  llvm_unreachable("Unhandled __builtin_va_list type kind");
6238}
6239
6240TypedefDecl *ASTContext::getBuiltinVaListDecl() const {
6241  if (!BuiltinVaListDecl) {
6242    BuiltinVaListDecl = CreateVaListDecl(this, Target->getBuiltinVaListKind());
6243    assert(BuiltinVaListDecl->isImplicit());
6244  }
6245
6246  return BuiltinVaListDecl;
6247}
6248
6249QualType ASTContext::getVaListTagType() const {
6250  // Force the creation of VaListTagTy by building the __builtin_va_list
6251  // declaration.
6252  if (VaListTagTy.isNull())
6253    (void) getBuiltinVaListDecl();
6254
6255  return VaListTagTy;
6256}
6257
6258void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
6259  assert(ObjCConstantStringType.isNull() &&
6260         "'NSConstantString' type already set!");
6261
6262  ObjCConstantStringType = getObjCInterfaceType(Decl);
6263}
6264
6265/// \brief Retrieve the template name that corresponds to a non-empty
6266/// lookup.
6267TemplateName
6268ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
6269                                      UnresolvedSetIterator End) const {
6270  unsigned size = End - Begin;
6271  assert(size > 1 && "set is not overloaded!");
6272
6273  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
6274                          size * sizeof(FunctionTemplateDecl*));
6275  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
6276
6277  NamedDecl **Storage = OT->getStorage();
6278  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
6279    NamedDecl *D = *I;
6280    assert(isa<FunctionTemplateDecl>(D) ||
6281           (isa<UsingShadowDecl>(D) &&
6282            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
6283    *Storage++ = D;
6284  }
6285
6286  return TemplateName(OT);
6287}
6288
6289/// \brief Retrieve the template name that represents a qualified
6290/// template name such as \c std::vector.
6291TemplateName
6292ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
6293                                     bool TemplateKeyword,
6294                                     TemplateDecl *Template) const {
6295  assert(NNS && "Missing nested-name-specifier in qualified template name");
6296
6297  // FIXME: Canonicalization?
6298  llvm::FoldingSetNodeID ID;
6299  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
6300
6301  void *InsertPos = nullptr;
6302  QualifiedTemplateName *QTN =
6303    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6304  if (!QTN) {
6305    QTN = new (*this, llvm::alignOf<QualifiedTemplateName>())
6306        QualifiedTemplateName(NNS, TemplateKeyword, Template);
6307    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
6308  }
6309
6310  return TemplateName(QTN);
6311}
6312
6313/// \brief Retrieve the template name that represents a dependent
6314/// template name such as \c MetaFun::template apply.
6315TemplateName
6316ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
6317                                     const IdentifierInfo *Name) const {
6318  assert((!NNS || NNS->isDependent()) &&
6319         "Nested name specifier must be dependent");
6320
6321  llvm::FoldingSetNodeID ID;
6322  DependentTemplateName::Profile(ID, NNS, Name);
6323
6324  void *InsertPos = nullptr;
6325  DependentTemplateName *QTN =
6326    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6327
6328  if (QTN)
6329    return TemplateName(QTN);
6330
6331  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
6332  if (CanonNNS == NNS) {
6333    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6334        DependentTemplateName(NNS, Name);
6335  } else {
6336    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
6337    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6338        DependentTemplateName(NNS, Name, Canon);
6339    DependentTemplateName *CheckQTN =
6340      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6341    assert(!CheckQTN && "Dependent type name canonicalization broken");
6342    (void)CheckQTN;
6343  }
6344
6345  DependentTemplateNames.InsertNode(QTN, InsertPos);
6346  return TemplateName(QTN);
6347}
6348
6349/// \brief Retrieve the template name that represents a dependent
6350/// template name such as \c MetaFun::template operator+.
6351TemplateName
6352ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
6353                                     OverloadedOperatorKind Operator) const {
6354  assert((!NNS || NNS->isDependent()) &&
6355         "Nested name specifier must be dependent");
6356
6357  llvm::FoldingSetNodeID ID;
6358  DependentTemplateName::Profile(ID, NNS, Operator);
6359
6360  void *InsertPos = nullptr;
6361  DependentTemplateName *QTN
6362    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6363
6364  if (QTN)
6365    return TemplateName(QTN);
6366
6367  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
6368  if (CanonNNS == NNS) {
6369    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6370        DependentTemplateName(NNS, Operator);
6371  } else {
6372    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
6373    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6374        DependentTemplateName(NNS, Operator, Canon);
6375
6376    DependentTemplateName *CheckQTN
6377      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6378    assert(!CheckQTN && "Dependent template name canonicalization broken");
6379    (void)CheckQTN;
6380  }
6381
6382  DependentTemplateNames.InsertNode(QTN, InsertPos);
6383  return TemplateName(QTN);
6384}
6385
6386TemplateName
6387ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
6388                                         TemplateName replacement) const {
6389  llvm::FoldingSetNodeID ID;
6390  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
6391
6392  void *insertPos = nullptr;
6393  SubstTemplateTemplateParmStorage *subst
6394    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
6395
6396  if (!subst) {
6397    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
6398    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
6399  }
6400
6401  return TemplateName(subst);
6402}
6403
6404TemplateName
6405ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
6406                                       const TemplateArgument &ArgPack) const {
6407  ASTContext &Self = const_cast<ASTContext &>(*this);
6408  llvm::FoldingSetNodeID ID;
6409  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
6410
6411  void *InsertPos = nullptr;
6412  SubstTemplateTemplateParmPackStorage *Subst
6413    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
6414
6415  if (!Subst) {
6416    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
6417                                                           ArgPack.pack_size(),
6418                                                         ArgPack.pack_begin());
6419    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
6420  }
6421
6422  return TemplateName(Subst);
6423}
6424
6425/// getFromTargetType - Given one of the integer types provided by
6426/// TargetInfo, produce the corresponding type. The unsigned @p Type
6427/// is actually a value of type @c TargetInfo::IntType.
6428CanQualType ASTContext::getFromTargetType(unsigned Type) const {
6429  switch (Type) {
6430  case TargetInfo::NoInt: return CanQualType();
6431  case TargetInfo::SignedChar: return SignedCharTy;
6432  case TargetInfo::UnsignedChar: return UnsignedCharTy;
6433  case TargetInfo::SignedShort: return ShortTy;
6434  case TargetInfo::UnsignedShort: return UnsignedShortTy;
6435  case TargetInfo::SignedInt: return IntTy;
6436  case TargetInfo::UnsignedInt: return UnsignedIntTy;
6437  case TargetInfo::SignedLong: return LongTy;
6438  case TargetInfo::UnsignedLong: return UnsignedLongTy;
6439  case TargetInfo::SignedLongLong: return LongLongTy;
6440  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
6441  }
6442
6443  llvm_unreachable("Unhandled TargetInfo::IntType value");
6444}
6445
6446//===----------------------------------------------------------------------===//
6447//                        Type Predicates.
6448//===----------------------------------------------------------------------===//
6449
6450/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
6451/// garbage collection attribute.
6452///
6453Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
6454  if (getLangOpts().getGC() == LangOptions::NonGC)
6455    return Qualifiers::GCNone;
6456
6457  assert(getLangOpts().ObjC1);
6458  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
6459
6460  // Default behaviour under objective-C's gc is for ObjC pointers
6461  // (or pointers to them) be treated as though they were declared
6462  // as __strong.
6463  if (GCAttrs == Qualifiers::GCNone) {
6464    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
6465      return Qualifiers::Strong;
6466    else if (Ty->isPointerType())
6467      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
6468  } else {
6469    // It's not valid to set GC attributes on anything that isn't a
6470    // pointer.
6471#ifndef NDEBUG
6472    QualType CT = Ty->getCanonicalTypeInternal();
6473    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
6474      CT = AT->getElementType();
6475    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
6476#endif
6477  }
6478  return GCAttrs;
6479}
6480
6481//===----------------------------------------------------------------------===//
6482//                        Type Compatibility Testing
6483//===----------------------------------------------------------------------===//
6484
6485/// areCompatVectorTypes - Return true if the two specified vector types are
6486/// compatible.
6487static bool areCompatVectorTypes(const VectorType *LHS,
6488                                 const VectorType *RHS) {
6489  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
6490  return LHS->getElementType() == RHS->getElementType() &&
6491         LHS->getNumElements() == RHS->getNumElements();
6492}
6493
6494bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
6495                                          QualType SecondVec) {
6496  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
6497  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
6498
6499  if (hasSameUnqualifiedType(FirstVec, SecondVec))
6500    return true;
6501
6502  // Treat Neon vector types and most AltiVec vector types as if they are the
6503  // equivalent GCC vector types.
6504  const VectorType *First = FirstVec->getAs<VectorType>();
6505  const VectorType *Second = SecondVec->getAs<VectorType>();
6506  if (First->getNumElements() == Second->getNumElements() &&
6507      hasSameType(First->getElementType(), Second->getElementType()) &&
6508      First->getVectorKind() != VectorType::AltiVecPixel &&
6509      First->getVectorKind() != VectorType::AltiVecBool &&
6510      Second->getVectorKind() != VectorType::AltiVecPixel &&
6511      Second->getVectorKind() != VectorType::AltiVecBool)
6512    return true;
6513
6514  return false;
6515}
6516
6517//===----------------------------------------------------------------------===//
6518// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
6519//===----------------------------------------------------------------------===//
6520
6521/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
6522/// inheritance hierarchy of 'rProto'.
6523bool
6524ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
6525                                           ObjCProtocolDecl *rProto) const {
6526  if (declaresSameEntity(lProto, rProto))
6527    return true;
6528  for (auto *PI : rProto->protocols())
6529    if (ProtocolCompatibleWithProtocol(lProto, PI))
6530      return true;
6531  return false;
6532}
6533
6534/// ObjCQualifiedClassTypesAreCompatible - compare  Class<pr,...> and
6535/// Class<pr1, ...>.
6536bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
6537                                                      QualType rhs) {
6538  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
6539  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
6540  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
6541
6542  for (auto *lhsProto : lhsQID->quals()) {
6543    bool match = false;
6544    for (auto *rhsProto : rhsOPT->quals()) {
6545      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
6546        match = true;
6547        break;
6548      }
6549    }
6550    if (!match)
6551      return false;
6552  }
6553  return true;
6554}
6555
6556/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
6557/// ObjCQualifiedIDType.
6558bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
6559                                                   bool compare) {
6560  // Allow id<P..> and an 'id' or void* type in all cases.
6561  if (lhs->isVoidPointerType() ||
6562      lhs->isObjCIdType() || lhs->isObjCClassType())
6563    return true;
6564  else if (rhs->isVoidPointerType() ||
6565           rhs->isObjCIdType() || rhs->isObjCClassType())
6566    return true;
6567
6568  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
6569    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
6570
6571    if (!rhsOPT) return false;
6572
6573    if (rhsOPT->qual_empty()) {
6574      // If the RHS is a unqualified interface pointer "NSString*",
6575      // make sure we check the class hierarchy.
6576      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
6577        for (auto *I : lhsQID->quals()) {
6578          // when comparing an id<P> on lhs with a static type on rhs,
6579          // see if static class implements all of id's protocols, directly or
6580          // through its super class and categories.
6581          if (!rhsID->ClassImplementsProtocol(I, true))
6582            return false;
6583        }
6584      }
6585      // If there are no qualifiers and no interface, we have an 'id'.
6586      return true;
6587    }
6588    // Both the right and left sides have qualifiers.
6589    for (auto *lhsProto : lhsQID->quals()) {
6590      bool match = false;
6591
6592      // when comparing an id<P> on lhs with a static type on rhs,
6593      // see if static class implements all of id's protocols, directly or
6594      // through its super class and categories.
6595      for (auto *rhsProto : rhsOPT->quals()) {
6596        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6597            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6598          match = true;
6599          break;
6600        }
6601      }
6602      // If the RHS is a qualified interface pointer "NSString<P>*",
6603      // make sure we check the class hierarchy.
6604      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
6605        for (auto *I : lhsQID->quals()) {
6606          // when comparing an id<P> on lhs with a static type on rhs,
6607          // see if static class implements all of id's protocols, directly or
6608          // through its super class and categories.
6609          if (rhsID->ClassImplementsProtocol(I, true)) {
6610            match = true;
6611            break;
6612          }
6613        }
6614      }
6615      if (!match)
6616        return false;
6617    }
6618
6619    return true;
6620  }
6621
6622  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
6623  assert(rhsQID && "One of the LHS/RHS should be id<x>");
6624
6625  if (const ObjCObjectPointerType *lhsOPT =
6626        lhs->getAsObjCInterfacePointerType()) {
6627    // If both the right and left sides have qualifiers.
6628    for (auto *lhsProto : lhsOPT->quals()) {
6629      bool match = false;
6630
6631      // when comparing an id<P> on rhs with a static type on lhs,
6632      // see if static class implements all of id's protocols, directly or
6633      // through its super class and categories.
6634      // First, lhs protocols in the qualifier list must be found, direct
6635      // or indirect in rhs's qualifier list or it is a mismatch.
6636      for (auto *rhsProto : rhsQID->quals()) {
6637        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6638            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6639          match = true;
6640          break;
6641        }
6642      }
6643      if (!match)
6644        return false;
6645    }
6646
6647    // Static class's protocols, or its super class or category protocols
6648    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
6649    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
6650      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
6651      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
6652      // This is rather dubious but matches gcc's behavior. If lhs has
6653      // no type qualifier and its class has no static protocol(s)
6654      // assume that it is mismatch.
6655      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
6656        return false;
6657      for (auto *lhsProto : LHSInheritedProtocols) {
6658        bool match = false;
6659        for (auto *rhsProto : rhsQID->quals()) {
6660          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6661              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6662            match = true;
6663            break;
6664          }
6665        }
6666        if (!match)
6667          return false;
6668      }
6669    }
6670    return true;
6671  }
6672  return false;
6673}
6674
6675/// canAssignObjCInterfaces - Return true if the two interface types are
6676/// compatible for assignment from RHS to LHS.  This handles validation of any
6677/// protocol qualifiers on the LHS or RHS.
6678///
6679bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
6680                                         const ObjCObjectPointerType *RHSOPT) {
6681  const ObjCObjectType* LHS = LHSOPT->getObjectType();
6682  const ObjCObjectType* RHS = RHSOPT->getObjectType();
6683
6684  // If either type represents the built-in 'id' or 'Class' types, return true.
6685  if (LHS->isObjCUnqualifiedIdOrClass() ||
6686      RHS->isObjCUnqualifiedIdOrClass())
6687    return true;
6688
6689  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
6690    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
6691                                             QualType(RHSOPT,0),
6692                                             false);
6693
6694  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
6695    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
6696                                                QualType(RHSOPT,0));
6697
6698  // If we have 2 user-defined types, fall into that path.
6699  if (LHS->getInterface() && RHS->getInterface())
6700    return canAssignObjCInterfaces(LHS, RHS);
6701
6702  return false;
6703}
6704
6705/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
6706/// for providing type-safety for objective-c pointers used to pass/return
6707/// arguments in block literals. When passed as arguments, passing 'A*' where
6708/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
6709/// not OK. For the return type, the opposite is not OK.
6710bool ASTContext::canAssignObjCInterfacesInBlockPointer(
6711                                         const ObjCObjectPointerType *LHSOPT,
6712                                         const ObjCObjectPointerType *RHSOPT,
6713                                         bool BlockReturnType) {
6714  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
6715    return true;
6716
6717  if (LHSOPT->isObjCBuiltinType()) {
6718    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
6719  }
6720
6721  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
6722    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
6723                                             QualType(RHSOPT,0),
6724                                             false);
6725
6726  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
6727  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
6728  if (LHS && RHS)  { // We have 2 user-defined types.
6729    if (LHS != RHS) {
6730      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
6731        return BlockReturnType;
6732      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
6733        return !BlockReturnType;
6734    }
6735    else
6736      return true;
6737  }
6738  return false;
6739}
6740
6741/// getIntersectionOfProtocols - This routine finds the intersection of set
6742/// of protocols inherited from two distinct objective-c pointer objects.
6743/// It is used to build composite qualifier list of the composite type of
6744/// the conditional expression involving two objective-c pointer objects.
6745static
6746void getIntersectionOfProtocols(ASTContext &Context,
6747                                const ObjCObjectPointerType *LHSOPT,
6748                                const ObjCObjectPointerType *RHSOPT,
6749      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
6750
6751  const ObjCObjectType* LHS = LHSOPT->getObjectType();
6752  const ObjCObjectType* RHS = RHSOPT->getObjectType();
6753  assert(LHS->getInterface() && "LHS must have an interface base");
6754  assert(RHS->getInterface() && "RHS must have an interface base");
6755
6756  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
6757  unsigned LHSNumProtocols = LHS->getNumProtocols();
6758  if (LHSNumProtocols > 0)
6759    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
6760  else {
6761    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
6762    Context.CollectInheritedProtocols(LHS->getInterface(),
6763                                      LHSInheritedProtocols);
6764    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
6765                                LHSInheritedProtocols.end());
6766  }
6767
6768  unsigned RHSNumProtocols = RHS->getNumProtocols();
6769  if (RHSNumProtocols > 0) {
6770    ObjCProtocolDecl **RHSProtocols =
6771      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
6772    for (unsigned i = 0; i < RHSNumProtocols; ++i)
6773      if (InheritedProtocolSet.count(RHSProtocols[i]))
6774        IntersectionOfProtocols.push_back(RHSProtocols[i]);
6775  } else {
6776    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
6777    Context.CollectInheritedProtocols(RHS->getInterface(),
6778                                      RHSInheritedProtocols);
6779    for (ObjCProtocolDecl *ProtDecl : RHSInheritedProtocols)
6780      if (InheritedProtocolSet.count(ProtDecl))
6781        IntersectionOfProtocols.push_back(ProtDecl);
6782  }
6783}
6784
6785/// areCommonBaseCompatible - Returns common base class of the two classes if
6786/// one found. Note that this is O'2 algorithm. But it will be called as the
6787/// last type comparison in a ?-exp of ObjC pointer types before a
6788/// warning is issued. So, its invokation is extremely rare.
6789QualType ASTContext::areCommonBaseCompatible(
6790                                          const ObjCObjectPointerType *Lptr,
6791                                          const ObjCObjectPointerType *Rptr) {
6792  const ObjCObjectType *LHS = Lptr->getObjectType();
6793  const ObjCObjectType *RHS = Rptr->getObjectType();
6794  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
6795  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
6796  if (!LDecl || !RDecl || (declaresSameEntity(LDecl, RDecl)))
6797    return QualType();
6798
6799  do {
6800    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
6801    if (canAssignObjCInterfaces(LHS, RHS)) {
6802      SmallVector<ObjCProtocolDecl *, 8> Protocols;
6803      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
6804
6805      QualType Result = QualType(LHS, 0);
6806      if (!Protocols.empty())
6807        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
6808      Result = getObjCObjectPointerType(Result);
6809      return Result;
6810    }
6811  } while ((LDecl = LDecl->getSuperClass()));
6812
6813  return QualType();
6814}
6815
6816bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
6817                                         const ObjCObjectType *RHS) {
6818  assert(LHS->getInterface() && "LHS is not an interface type");
6819  assert(RHS->getInterface() && "RHS is not an interface type");
6820
6821  // Verify that the base decls are compatible: the RHS must be a subclass of
6822  // the LHS.
6823  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
6824    return false;
6825
6826  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
6827  // protocol qualified at all, then we are good.
6828  if (LHS->getNumProtocols() == 0)
6829    return true;
6830
6831  // Okay, we know the LHS has protocol qualifiers. But RHS may or may not.
6832  // More detailed analysis is required.
6833  // OK, if LHS is same or a superclass of RHS *and*
6834  // this LHS, or as RHS's super class is assignment compatible with LHS.
6835  bool IsSuperClass =
6836    LHS->getInterface()->isSuperClassOf(RHS->getInterface());
6837  if (IsSuperClass) {
6838    // OK if conversion of LHS to SuperClass results in narrowing of types
6839    // ; i.e., SuperClass may implement at least one of the protocols
6840    // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
6841    // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
6842    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
6843    CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
6844    // Also, if RHS has explicit quelifiers, include them for comparing with LHS's
6845    // qualifiers.
6846    for (auto *RHSPI : RHS->quals())
6847      SuperClassInheritedProtocols.insert(RHSPI->getCanonicalDecl());
6848    // If there is no protocols associated with RHS, it is not a match.
6849    if (SuperClassInheritedProtocols.empty())
6850      return false;
6851
6852    for (const auto *LHSProto : LHS->quals()) {
6853      bool SuperImplementsProtocol = false;
6854      for (auto *SuperClassProto : SuperClassInheritedProtocols)
6855        if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
6856          SuperImplementsProtocol = true;
6857          break;
6858        }
6859      if (!SuperImplementsProtocol)
6860        return false;
6861    }
6862    return true;
6863  }
6864  return false;
6865}
6866
6867bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
6868  // get the "pointed to" types
6869  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
6870  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
6871
6872  if (!LHSOPT || !RHSOPT)
6873    return false;
6874
6875  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
6876         canAssignObjCInterfaces(RHSOPT, LHSOPT);
6877}
6878
6879bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
6880  return canAssignObjCInterfaces(
6881                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
6882                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
6883}
6884
6885/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
6886/// both shall have the identically qualified version of a compatible type.
6887/// C99 6.2.7p1: Two types have compatible types if their types are the
6888/// same. See 6.7.[2,3,5] for additional rules.
6889bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
6890                                    bool CompareUnqualified) {
6891  if (getLangOpts().CPlusPlus)
6892    return hasSameType(LHS, RHS);
6893
6894  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
6895}
6896
6897bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
6898  return typesAreCompatible(LHS, RHS);
6899}
6900
6901bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
6902  return !mergeTypes(LHS, RHS, true).isNull();
6903}
6904
6905/// mergeTransparentUnionType - if T is a transparent union type and a member
6906/// of T is compatible with SubType, return the merged type, else return
6907/// QualType()
6908QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
6909                                               bool OfBlockPointer,
6910                                               bool Unqualified) {
6911  if (const RecordType *UT = T->getAsUnionType()) {
6912    RecordDecl *UD = UT->getDecl();
6913    if (UD->hasAttr<TransparentUnionAttr>()) {
6914      for (const auto *I : UD->fields()) {
6915        QualType ET = I->getType().getUnqualifiedType();
6916        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
6917        if (!MT.isNull())
6918          return MT;
6919      }
6920    }
6921  }
6922
6923  return QualType();
6924}
6925
6926/// mergeFunctionParameterTypes - merge two types which appear as function
6927/// parameter types
6928QualType ASTContext::mergeFunctionParameterTypes(QualType lhs, QualType rhs,
6929                                                 bool OfBlockPointer,
6930                                                 bool Unqualified) {
6931  // GNU extension: two types are compatible if they appear as a function
6932  // argument, one of the types is a transparent union type and the other
6933  // type is compatible with a union member
6934  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
6935                                              Unqualified);
6936  if (!lmerge.isNull())
6937    return lmerge;
6938
6939  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
6940                                              Unqualified);
6941  if (!rmerge.isNull())
6942    return rmerge;
6943
6944  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
6945}
6946
6947QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
6948                                        bool OfBlockPointer,
6949                                        bool Unqualified) {
6950  const FunctionType *lbase = lhs->getAs<FunctionType>();
6951  const FunctionType *rbase = rhs->getAs<FunctionType>();
6952  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
6953  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
6954  bool allLTypes = true;
6955  bool allRTypes = true;
6956
6957  // Check return type
6958  QualType retType;
6959  if (OfBlockPointer) {
6960    QualType RHS = rbase->getReturnType();
6961    QualType LHS = lbase->getReturnType();
6962    bool UnqualifiedResult = Unqualified;
6963    if (!UnqualifiedResult)
6964      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
6965    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
6966  }
6967  else
6968    retType = mergeTypes(lbase->getReturnType(), rbase->getReturnType(), false,
6969                         Unqualified);
6970  if (retType.isNull()) return QualType();
6971
6972  if (Unqualified)
6973    retType = retType.getUnqualifiedType();
6974
6975  CanQualType LRetType = getCanonicalType(lbase->getReturnType());
6976  CanQualType RRetType = getCanonicalType(rbase->getReturnType());
6977  if (Unqualified) {
6978    LRetType = LRetType.getUnqualifiedType();
6979    RRetType = RRetType.getUnqualifiedType();
6980  }
6981
6982  if (getCanonicalType(retType) != LRetType)
6983    allLTypes = false;
6984  if (getCanonicalType(retType) != RRetType)
6985    allRTypes = false;
6986
6987  // FIXME: double check this
6988  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
6989  //                           rbase->getRegParmAttr() != 0 &&
6990  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
6991  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
6992  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
6993
6994  // Compatible functions must have compatible calling conventions
6995  if (lbaseInfo.getCC() != rbaseInfo.getCC())
6996    return QualType();
6997
6998  // Regparm is part of the calling convention.
6999  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
7000    return QualType();
7001  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
7002    return QualType();
7003
7004  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
7005    return QualType();
7006
7007  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
7008  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
7009
7010  if (lbaseInfo.getNoReturn() != NoReturn)
7011    allLTypes = false;
7012  if (rbaseInfo.getNoReturn() != NoReturn)
7013    allRTypes = false;
7014
7015  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
7016
7017  if (lproto && rproto) { // two C99 style function prototypes
7018    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
7019           "C++ shouldn't be here");
7020    // Compatible functions must have the same number of parameters
7021    if (lproto->getNumParams() != rproto->getNumParams())
7022      return QualType();
7023
7024    // Variadic and non-variadic functions aren't compatible
7025    if (lproto->isVariadic() != rproto->isVariadic())
7026      return QualType();
7027
7028    if (lproto->getTypeQuals() != rproto->getTypeQuals())
7029      return QualType();
7030
7031    if (LangOpts.ObjCAutoRefCount &&
7032        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
7033      return QualType();
7034
7035    // Check parameter type compatibility
7036    SmallVector<QualType, 10> types;
7037    for (unsigned i = 0, n = lproto->getNumParams(); i < n; i++) {
7038      QualType lParamType = lproto->getParamType(i).getUnqualifiedType();
7039      QualType rParamType = rproto->getParamType(i).getUnqualifiedType();
7040      QualType paramType = mergeFunctionParameterTypes(
7041          lParamType, rParamType, OfBlockPointer, Unqualified);
7042      if (paramType.isNull())
7043        return QualType();
7044
7045      if (Unqualified)
7046        paramType = paramType.getUnqualifiedType();
7047
7048      types.push_back(paramType);
7049      if (Unqualified) {
7050        lParamType = lParamType.getUnqualifiedType();
7051        rParamType = rParamType.getUnqualifiedType();
7052      }
7053
7054      if (getCanonicalType(paramType) != getCanonicalType(lParamType))
7055        allLTypes = false;
7056      if (getCanonicalType(paramType) != getCanonicalType(rParamType))
7057        allRTypes = false;
7058    }
7059
7060    if (allLTypes) return lhs;
7061    if (allRTypes) return rhs;
7062
7063    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
7064    EPI.ExtInfo = einfo;
7065    return getFunctionType(retType, types, EPI);
7066  }
7067
7068  if (lproto) allRTypes = false;
7069  if (rproto) allLTypes = false;
7070
7071  const FunctionProtoType *proto = lproto ? lproto : rproto;
7072  if (proto) {
7073    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
7074    if (proto->isVariadic()) return QualType();
7075    // Check that the types are compatible with the types that
7076    // would result from default argument promotions (C99 6.7.5.3p15).
7077    // The only types actually affected are promotable integer
7078    // types and floats, which would be passed as a different
7079    // type depending on whether the prototype is visible.
7080    for (unsigned i = 0, n = proto->getNumParams(); i < n; ++i) {
7081      QualType paramTy = proto->getParamType(i);
7082
7083      // Look at the converted type of enum types, since that is the type used
7084      // to pass enum values.
7085      if (const EnumType *Enum = paramTy->getAs<EnumType>()) {
7086        paramTy = Enum->getDecl()->getIntegerType();
7087        if (paramTy.isNull())
7088          return QualType();
7089      }
7090
7091      if (paramTy->isPromotableIntegerType() ||
7092          getCanonicalType(paramTy).getUnqualifiedType() == FloatTy)
7093        return QualType();
7094    }
7095
7096    if (allLTypes) return lhs;
7097    if (allRTypes) return rhs;
7098
7099    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
7100    EPI.ExtInfo = einfo;
7101    return getFunctionType(retType, proto->getParamTypes(), EPI);
7102  }
7103
7104  if (allLTypes) return lhs;
7105  if (allRTypes) return rhs;
7106  return getFunctionNoProtoType(retType, einfo);
7107}
7108
7109/// Given that we have an enum type and a non-enum type, try to merge them.
7110static QualType mergeEnumWithInteger(ASTContext &Context, const EnumType *ET,
7111                                     QualType other, bool isBlockReturnType) {
7112  // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
7113  // a signed integer type, or an unsigned integer type.
7114  // Compatibility is based on the underlying type, not the promotion
7115  // type.
7116  QualType underlyingType = ET->getDecl()->getIntegerType();
7117  if (underlyingType.isNull()) return QualType();
7118  if (Context.hasSameType(underlyingType, other))
7119    return other;
7120
7121  // In block return types, we're more permissive and accept any
7122  // integral type of the same size.
7123  if (isBlockReturnType && other->isIntegerType() &&
7124      Context.getTypeSize(underlyingType) == Context.getTypeSize(other))
7125    return other;
7126
7127  return QualType();
7128}
7129
7130QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
7131                                bool OfBlockPointer,
7132                                bool Unqualified, bool BlockReturnType) {
7133  // C++ [expr]: If an expression initially has the type "reference to T", the
7134  // type is adjusted to "T" prior to any further analysis, the expression
7135  // designates the object or function denoted by the reference, and the
7136  // expression is an lvalue unless the reference is an rvalue reference and
7137  // the expression is a function call (possibly inside parentheses).
7138  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
7139  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
7140
7141  if (Unqualified) {
7142    LHS = LHS.getUnqualifiedType();
7143    RHS = RHS.getUnqualifiedType();
7144  }
7145
7146  QualType LHSCan = getCanonicalType(LHS),
7147           RHSCan = getCanonicalType(RHS);
7148
7149  // If two types are identical, they are compatible.
7150  if (LHSCan == RHSCan)
7151    return LHS;
7152
7153  // If the qualifiers are different, the types aren't compatible... mostly.
7154  Qualifiers LQuals = LHSCan.getLocalQualifiers();
7155  Qualifiers RQuals = RHSCan.getLocalQualifiers();
7156  if (LQuals != RQuals) {
7157    // If any of these qualifiers are different, we have a type
7158    // mismatch.
7159    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
7160        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
7161        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
7162      return QualType();
7163
7164    // Exactly one GC qualifier difference is allowed: __strong is
7165    // okay if the other type has no GC qualifier but is an Objective
7166    // C object pointer (i.e. implicitly strong by default).  We fix
7167    // this by pretending that the unqualified type was actually
7168    // qualified __strong.
7169    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
7170    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
7171    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
7172
7173    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
7174      return QualType();
7175
7176    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
7177      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
7178    }
7179    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
7180      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
7181    }
7182    return QualType();
7183  }
7184
7185  // Okay, qualifiers are equal.
7186
7187  Type::TypeClass LHSClass = LHSCan->getTypeClass();
7188  Type::TypeClass RHSClass = RHSCan->getTypeClass();
7189
7190  // We want to consider the two function types to be the same for these
7191  // comparisons, just force one to the other.
7192  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
7193  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
7194
7195  // Same as above for arrays
7196  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
7197    LHSClass = Type::ConstantArray;
7198  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
7199    RHSClass = Type::ConstantArray;
7200
7201  // ObjCInterfaces are just specialized ObjCObjects.
7202  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
7203  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
7204
7205  // Canonicalize ExtVector -> Vector.
7206  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
7207  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
7208
7209  // If the canonical type classes don't match.
7210  if (LHSClass != RHSClass) {
7211    // Note that we only have special rules for turning block enum
7212    // returns into block int returns, not vice-versa.
7213    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
7214      return mergeEnumWithInteger(*this, ETy, RHS, false);
7215    }
7216    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
7217      return mergeEnumWithInteger(*this, ETy, LHS, BlockReturnType);
7218    }
7219    // allow block pointer type to match an 'id' type.
7220    if (OfBlockPointer && !BlockReturnType) {
7221       if (LHS->isObjCIdType() && RHS->isBlockPointerType())
7222         return LHS;
7223      if (RHS->isObjCIdType() && LHS->isBlockPointerType())
7224        return RHS;
7225    }
7226
7227    return QualType();
7228  }
7229
7230  // The canonical type classes match.
7231  switch (LHSClass) {
7232#define TYPE(Class, Base)
7233#define ABSTRACT_TYPE(Class, Base)
7234#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
7235#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
7236#define DEPENDENT_TYPE(Class, Base) case Type::Class:
7237#include "clang/AST/TypeNodes.def"
7238    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
7239
7240  case Type::Auto:
7241  case Type::LValueReference:
7242  case Type::RValueReference:
7243  case Type::MemberPointer:
7244    llvm_unreachable("C++ should never be in mergeTypes");
7245
7246  case Type::ObjCInterface:
7247  case Type::IncompleteArray:
7248  case Type::VariableArray:
7249  case Type::FunctionProto:
7250  case Type::ExtVector:
7251    llvm_unreachable("Types are eliminated above");
7252
7253  case Type::Pointer:
7254  {
7255    // Merge two pointer types, while trying to preserve typedef info
7256    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
7257    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
7258    if (Unqualified) {
7259      LHSPointee = LHSPointee.getUnqualifiedType();
7260      RHSPointee = RHSPointee.getUnqualifiedType();
7261    }
7262    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
7263                                     Unqualified);
7264    if (ResultType.isNull()) return QualType();
7265    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
7266      return LHS;
7267    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
7268      return RHS;
7269    return getPointerType(ResultType);
7270  }
7271  case Type::BlockPointer:
7272  {
7273    // Merge two block pointer types, while trying to preserve typedef info
7274    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
7275    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
7276    if (Unqualified) {
7277      LHSPointee = LHSPointee.getUnqualifiedType();
7278      RHSPointee = RHSPointee.getUnqualifiedType();
7279    }
7280    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
7281                                     Unqualified);
7282    if (ResultType.isNull()) return QualType();
7283    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
7284      return LHS;
7285    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
7286      return RHS;
7287    return getBlockPointerType(ResultType);
7288  }
7289  case Type::Atomic:
7290  {
7291    // Merge two pointer types, while trying to preserve typedef info
7292    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
7293    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
7294    if (Unqualified) {
7295      LHSValue = LHSValue.getUnqualifiedType();
7296      RHSValue = RHSValue.getUnqualifiedType();
7297    }
7298    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
7299                                     Unqualified);
7300    if (ResultType.isNull()) return QualType();
7301    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
7302      return LHS;
7303    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
7304      return RHS;
7305    return getAtomicType(ResultType);
7306  }
7307  case Type::ConstantArray:
7308  {
7309    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
7310    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
7311    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
7312      return QualType();
7313
7314    QualType LHSElem = getAsArrayType(LHS)->getElementType();
7315    QualType RHSElem = getAsArrayType(RHS)->getElementType();
7316    if (Unqualified) {
7317      LHSElem = LHSElem.getUnqualifiedType();
7318      RHSElem = RHSElem.getUnqualifiedType();
7319    }
7320
7321    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
7322    if (ResultType.isNull()) return QualType();
7323    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
7324      return LHS;
7325    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
7326      return RHS;
7327    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
7328                                          ArrayType::ArraySizeModifier(), 0);
7329    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
7330                                          ArrayType::ArraySizeModifier(), 0);
7331    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
7332    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
7333    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
7334      return LHS;
7335    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
7336      return RHS;
7337    if (LVAT) {
7338      // FIXME: This isn't correct! But tricky to implement because
7339      // the array's size has to be the size of LHS, but the type
7340      // has to be different.
7341      return LHS;
7342    }
7343    if (RVAT) {
7344      // FIXME: This isn't correct! But tricky to implement because
7345      // the array's size has to be the size of RHS, but the type
7346      // has to be different.
7347      return RHS;
7348    }
7349    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
7350    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
7351    return getIncompleteArrayType(ResultType,
7352                                  ArrayType::ArraySizeModifier(), 0);
7353  }
7354  case Type::FunctionNoProto:
7355    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
7356  case Type::Record:
7357  case Type::Enum:
7358    return QualType();
7359  case Type::Builtin:
7360    // Only exactly equal builtin types are compatible, which is tested above.
7361    return QualType();
7362  case Type::Complex:
7363    // Distinct complex types are incompatible.
7364    return QualType();
7365  case Type::Vector:
7366    // FIXME: The merged type should be an ExtVector!
7367    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
7368                             RHSCan->getAs<VectorType>()))
7369      return LHS;
7370    return QualType();
7371  case Type::ObjCObject: {
7372    // Check if the types are assignment compatible.
7373    // FIXME: This should be type compatibility, e.g. whether
7374    // "LHS x; RHS x;" at global scope is legal.
7375    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
7376    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
7377    if (canAssignObjCInterfaces(LHSIface, RHSIface))
7378      return LHS;
7379
7380    return QualType();
7381  }
7382  case Type::ObjCObjectPointer: {
7383    if (OfBlockPointer) {
7384      if (canAssignObjCInterfacesInBlockPointer(
7385                                          LHS->getAs<ObjCObjectPointerType>(),
7386                                          RHS->getAs<ObjCObjectPointerType>(),
7387                                          BlockReturnType))
7388        return LHS;
7389      return QualType();
7390    }
7391    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
7392                                RHS->getAs<ObjCObjectPointerType>()))
7393      return LHS;
7394
7395    return QualType();
7396  }
7397  }
7398
7399  llvm_unreachable("Invalid Type::Class!");
7400}
7401
7402bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
7403                   const FunctionProtoType *FromFunctionType,
7404                   const FunctionProtoType *ToFunctionType) {
7405  if (FromFunctionType->hasAnyConsumedParams() !=
7406      ToFunctionType->hasAnyConsumedParams())
7407    return false;
7408  FunctionProtoType::ExtProtoInfo FromEPI =
7409    FromFunctionType->getExtProtoInfo();
7410  FunctionProtoType::ExtProtoInfo ToEPI =
7411    ToFunctionType->getExtProtoInfo();
7412  if (FromEPI.ConsumedParameters && ToEPI.ConsumedParameters)
7413    for (unsigned i = 0, n = FromFunctionType->getNumParams(); i != n; ++i) {
7414      if (FromEPI.ConsumedParameters[i] != ToEPI.ConsumedParameters[i])
7415        return false;
7416    }
7417  return true;
7418}
7419
7420/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
7421/// 'RHS' attributes and returns the merged version; including for function
7422/// return types.
7423QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
7424  QualType LHSCan = getCanonicalType(LHS),
7425  RHSCan = getCanonicalType(RHS);
7426  // If two types are identical, they are compatible.
7427  if (LHSCan == RHSCan)
7428    return LHS;
7429  if (RHSCan->isFunctionType()) {
7430    if (!LHSCan->isFunctionType())
7431      return QualType();
7432    QualType OldReturnType =
7433        cast<FunctionType>(RHSCan.getTypePtr())->getReturnType();
7434    QualType NewReturnType =
7435        cast<FunctionType>(LHSCan.getTypePtr())->getReturnType();
7436    QualType ResReturnType =
7437      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
7438    if (ResReturnType.isNull())
7439      return QualType();
7440    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
7441      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
7442      // In either case, use OldReturnType to build the new function type.
7443      const FunctionType *F = LHS->getAs<FunctionType>();
7444      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
7445        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
7446        EPI.ExtInfo = getFunctionExtInfo(LHS);
7447        QualType ResultType =
7448            getFunctionType(OldReturnType, FPT->getParamTypes(), EPI);
7449        return ResultType;
7450      }
7451    }
7452    return QualType();
7453  }
7454
7455  // If the qualifiers are different, the types can still be merged.
7456  Qualifiers LQuals = LHSCan.getLocalQualifiers();
7457  Qualifiers RQuals = RHSCan.getLocalQualifiers();
7458  if (LQuals != RQuals) {
7459    // If any of these qualifiers are different, we have a type mismatch.
7460    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
7461        LQuals.getAddressSpace() != RQuals.getAddressSpace())
7462      return QualType();
7463
7464    // Exactly one GC qualifier difference is allowed: __strong is
7465    // okay if the other type has no GC qualifier but is an Objective
7466    // C object pointer (i.e. implicitly strong by default).  We fix
7467    // this by pretending that the unqualified type was actually
7468    // qualified __strong.
7469    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
7470    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
7471    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
7472
7473    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
7474      return QualType();
7475
7476    if (GC_L == Qualifiers::Strong)
7477      return LHS;
7478    if (GC_R == Qualifiers::Strong)
7479      return RHS;
7480    return QualType();
7481  }
7482
7483  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
7484    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
7485    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
7486    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
7487    if (ResQT == LHSBaseQT)
7488      return LHS;
7489    if (ResQT == RHSBaseQT)
7490      return RHS;
7491  }
7492  return QualType();
7493}
7494
7495//===----------------------------------------------------------------------===//
7496//                         Integer Predicates
7497//===----------------------------------------------------------------------===//
7498
7499unsigned ASTContext::getIntWidth(QualType T) const {
7500  if (const EnumType *ET = T->getAs<EnumType>())
7501    T = ET->getDecl()->getIntegerType();
7502  if (T->isBooleanType())
7503    return 1;
7504  // For builtin types, just use the standard type sizing method
7505  return (unsigned)getTypeSize(T);
7506}
7507
7508QualType ASTContext::getCorrespondingUnsignedType(QualType T) const {
7509  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
7510
7511  // Turn <4 x signed int> -> <4 x unsigned int>
7512  if (const VectorType *VTy = T->getAs<VectorType>())
7513    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
7514                         VTy->getNumElements(), VTy->getVectorKind());
7515
7516  // For enums, we return the unsigned version of the base type.
7517  if (const EnumType *ETy = T->getAs<EnumType>())
7518    T = ETy->getDecl()->getIntegerType();
7519
7520  const BuiltinType *BTy = T->getAs<BuiltinType>();
7521  assert(BTy && "Unexpected signed integer type");
7522  switch (BTy->getKind()) {
7523  case BuiltinType::Char_S:
7524  case BuiltinType::SChar:
7525    return UnsignedCharTy;
7526  case BuiltinType::Short:
7527    return UnsignedShortTy;
7528  case BuiltinType::Int:
7529    return UnsignedIntTy;
7530  case BuiltinType::Long:
7531    return UnsignedLongTy;
7532  case BuiltinType::LongLong:
7533    return UnsignedLongLongTy;
7534  case BuiltinType::Int128:
7535    return UnsignedInt128Ty;
7536  default:
7537    llvm_unreachable("Unexpected signed integer type");
7538  }
7539}
7540
7541ASTMutationListener::~ASTMutationListener() { }
7542
7543void ASTMutationListener::DeducedReturnType(const FunctionDecl *FD,
7544                                            QualType ReturnType) {}
7545
7546//===----------------------------------------------------------------------===//
7547//                          Builtin Type Computation
7548//===----------------------------------------------------------------------===//
7549
7550/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
7551/// pointer over the consumed characters.  This returns the resultant type.  If
7552/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
7553/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
7554/// a vector of "i*".
7555///
7556/// RequiresICE is filled in on return to indicate whether the value is required
7557/// to be an Integer Constant Expression.
7558static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
7559                                  ASTContext::GetBuiltinTypeError &Error,
7560                                  bool &RequiresICE,
7561                                  bool AllowTypeModifiers) {
7562  // Modifiers.
7563  int HowLong = 0;
7564  bool Signed = false, Unsigned = false;
7565  RequiresICE = false;
7566
7567  // Read the prefixed modifiers first.
7568  bool Done = false;
7569  while (!Done) {
7570    switch (*Str++) {
7571    default: Done = true; --Str; break;
7572    case 'I':
7573      RequiresICE = true;
7574      break;
7575    case 'S':
7576      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
7577      assert(!Signed && "Can't use 'S' modifier multiple times!");
7578      Signed = true;
7579      break;
7580    case 'U':
7581      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
7582      assert(!Unsigned && "Can't use 'U' modifier multiple times!");
7583      Unsigned = true;
7584      break;
7585    case 'L':
7586      assert(HowLong <= 2 && "Can't have LLLL modifier");
7587      ++HowLong;
7588      break;
7589    case 'W':
7590      // This modifier represents int64 type.
7591      assert(HowLong == 0 && "Can't use both 'L' and 'W' modifiers!");
7592      switch (Context.getTargetInfo().getInt64Type()) {
7593      default:
7594        llvm_unreachable("Unexpected integer type");
7595      case TargetInfo::SignedLong:
7596        HowLong = 1;
7597        break;
7598      case TargetInfo::SignedLongLong:
7599        HowLong = 2;
7600        break;
7601      }
7602    }
7603  }
7604
7605  QualType Type;
7606
7607  // Read the base type.
7608  switch (*Str++) {
7609  default: llvm_unreachable("Unknown builtin type letter!");
7610  case 'v':
7611    assert(HowLong == 0 && !Signed && !Unsigned &&
7612           "Bad modifiers used with 'v'!");
7613    Type = Context.VoidTy;
7614    break;
7615  case 'h':
7616    assert(HowLong == 0 && !Signed && !Unsigned &&
7617           "Bad modifiers used with 'h'!");
7618    Type = Context.HalfTy;
7619    break;
7620  case 'f':
7621    assert(HowLong == 0 && !Signed && !Unsigned &&
7622           "Bad modifiers used with 'f'!");
7623    Type = Context.FloatTy;
7624    break;
7625  case 'd':
7626    assert(HowLong < 2 && !Signed && !Unsigned &&
7627           "Bad modifiers used with 'd'!");
7628    if (HowLong)
7629      Type = Context.LongDoubleTy;
7630    else
7631      Type = Context.DoubleTy;
7632    break;
7633  case 's':
7634    assert(HowLong == 0 && "Bad modifiers used with 's'!");
7635    if (Unsigned)
7636      Type = Context.UnsignedShortTy;
7637    else
7638      Type = Context.ShortTy;
7639    break;
7640  case 'i':
7641    if (HowLong == 3)
7642      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
7643    else if (HowLong == 2)
7644      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
7645    else if (HowLong == 1)
7646      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
7647    else
7648      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
7649    break;
7650  case 'c':
7651    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
7652    if (Signed)
7653      Type = Context.SignedCharTy;
7654    else if (Unsigned)
7655      Type = Context.UnsignedCharTy;
7656    else
7657      Type = Context.CharTy;
7658    break;
7659  case 'b': // boolean
7660    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
7661    Type = Context.BoolTy;
7662    break;
7663  case 'z':  // size_t.
7664    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
7665    Type = Context.getSizeType();
7666    break;
7667  case 'F':
7668    Type = Context.getCFConstantStringType();
7669    break;
7670  case 'G':
7671    Type = Context.getObjCIdType();
7672    break;
7673  case 'H':
7674    Type = Context.getObjCSelType();
7675    break;
7676  case 'M':
7677    Type = Context.getObjCSuperType();
7678    break;
7679  case 'a':
7680    Type = Context.getBuiltinVaListType();
7681    assert(!Type.isNull() && "builtin va list type not initialized!");
7682    break;
7683  case 'A':
7684    // This is a "reference" to a va_list; however, what exactly
7685    // this means depends on how va_list is defined. There are two
7686    // different kinds of va_list: ones passed by value, and ones
7687    // passed by reference.  An example of a by-value va_list is
7688    // x86, where va_list is a char*. An example of by-ref va_list
7689    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
7690    // we want this argument to be a char*&; for x86-64, we want
7691    // it to be a __va_list_tag*.
7692    Type = Context.getBuiltinVaListType();
7693    assert(!Type.isNull() && "builtin va list type not initialized!");
7694    if (Type->isArrayType())
7695      Type = Context.getArrayDecayedType(Type);
7696    else
7697      Type = Context.getLValueReferenceType(Type);
7698    break;
7699  case 'V': {
7700    char *End;
7701    unsigned NumElements = strtoul(Str, &End, 10);
7702    assert(End != Str && "Missing vector size");
7703    Str = End;
7704
7705    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
7706                                             RequiresICE, false);
7707    assert(!RequiresICE && "Can't require vector ICE");
7708
7709    // TODO: No way to make AltiVec vectors in builtins yet.
7710    Type = Context.getVectorType(ElementType, NumElements,
7711                                 VectorType::GenericVector);
7712    break;
7713  }
7714  case 'E': {
7715    char *End;
7716
7717    unsigned NumElements = strtoul(Str, &End, 10);
7718    assert(End != Str && "Missing vector size");
7719
7720    Str = End;
7721
7722    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
7723                                             false);
7724    Type = Context.getExtVectorType(ElementType, NumElements);
7725    break;
7726  }
7727  case 'X': {
7728    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
7729                                             false);
7730    assert(!RequiresICE && "Can't require complex ICE");
7731    Type = Context.getComplexType(ElementType);
7732    break;
7733  }
7734  case 'Y' : {
7735    Type = Context.getPointerDiffType();
7736    break;
7737  }
7738  case 'P':
7739    Type = Context.getFILEType();
7740    if (Type.isNull()) {
7741      Error = ASTContext::GE_Missing_stdio;
7742      return QualType();
7743    }
7744    break;
7745  case 'J':
7746    if (Signed)
7747      Type = Context.getsigjmp_bufType();
7748    else
7749      Type = Context.getjmp_bufType();
7750
7751    if (Type.isNull()) {
7752      Error = ASTContext::GE_Missing_setjmp;
7753      return QualType();
7754    }
7755    break;
7756  case 'K':
7757    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'K'!");
7758    Type = Context.getucontext_tType();
7759
7760    if (Type.isNull()) {
7761      Error = ASTContext::GE_Missing_ucontext;
7762      return QualType();
7763    }
7764    break;
7765  case 'p':
7766    Type = Context.getProcessIDType();
7767    break;
7768  }
7769
7770  // If there are modifiers and if we're allowed to parse them, go for it.
7771  Done = !AllowTypeModifiers;
7772  while (!Done) {
7773    switch (char c = *Str++) {
7774    default: Done = true; --Str; break;
7775    case '*':
7776    case '&': {
7777      // Both pointers and references can have their pointee types
7778      // qualified with an address space.
7779      char *End;
7780      unsigned AddrSpace = strtoul(Str, &End, 10);
7781      if (End != Str && AddrSpace != 0) {
7782        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
7783        Str = End;
7784      }
7785      if (c == '*')
7786        Type = Context.getPointerType(Type);
7787      else
7788        Type = Context.getLValueReferenceType(Type);
7789      break;
7790    }
7791    // FIXME: There's no way to have a built-in with an rvalue ref arg.
7792    case 'C':
7793      Type = Type.withConst();
7794      break;
7795    case 'D':
7796      Type = Context.getVolatileType(Type);
7797      break;
7798    case 'R':
7799      Type = Type.withRestrict();
7800      break;
7801    }
7802  }
7803
7804  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
7805         "Integer constant 'I' type must be an integer");
7806
7807  return Type;
7808}
7809
7810/// GetBuiltinType - Return the type for the specified builtin.
7811QualType ASTContext::GetBuiltinType(unsigned Id,
7812                                    GetBuiltinTypeError &Error,
7813                                    unsigned *IntegerConstantArgs) const {
7814  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
7815
7816  SmallVector<QualType, 8> ArgTypes;
7817
7818  bool RequiresICE = false;
7819  Error = GE_None;
7820  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
7821                                       RequiresICE, true);
7822  if (Error != GE_None)
7823    return QualType();
7824
7825  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
7826
7827  while (TypeStr[0] && TypeStr[0] != '.') {
7828    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
7829    if (Error != GE_None)
7830      return QualType();
7831
7832    // If this argument is required to be an IntegerConstantExpression and the
7833    // caller cares, fill in the bitmask we return.
7834    if (RequiresICE && IntegerConstantArgs)
7835      *IntegerConstantArgs |= 1 << ArgTypes.size();
7836
7837    // Do array -> pointer decay.  The builtin should use the decayed type.
7838    if (Ty->isArrayType())
7839      Ty = getArrayDecayedType(Ty);
7840
7841    ArgTypes.push_back(Ty);
7842  }
7843
7844  if (Id == Builtin::BI__GetExceptionInfo)
7845    return QualType();
7846
7847  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
7848         "'.' should only occur at end of builtin type list!");
7849
7850  FunctionType::ExtInfo EI(CC_C);
7851  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
7852
7853  bool Variadic = (TypeStr[0] == '.');
7854
7855  // We really shouldn't be making a no-proto type here, especially in C++.
7856  if (ArgTypes.empty() && Variadic)
7857    return getFunctionNoProtoType(ResType, EI);
7858
7859  FunctionProtoType::ExtProtoInfo EPI;
7860  EPI.ExtInfo = EI;
7861  EPI.Variadic = Variadic;
7862
7863  return getFunctionType(ResType, ArgTypes, EPI);
7864}
7865
7866static GVALinkage basicGVALinkageForFunction(const ASTContext &Context,
7867                                             const FunctionDecl *FD) {
7868  if (!FD->isExternallyVisible())
7869    return GVA_Internal;
7870
7871  GVALinkage External = GVA_StrongExternal;
7872  switch (FD->getTemplateSpecializationKind()) {
7873  case TSK_Undeclared:
7874  case TSK_ExplicitSpecialization:
7875    External = GVA_StrongExternal;
7876    break;
7877
7878  case TSK_ExplicitInstantiationDefinition:
7879    return GVA_StrongODR;
7880
7881  // C++11 [temp.explicit]p10:
7882  //   [ Note: The intent is that an inline function that is the subject of
7883  //   an explicit instantiation declaration will still be implicitly
7884  //   instantiated when used so that the body can be considered for
7885  //   inlining, but that no out-of-line copy of the inline function would be
7886  //   generated in the translation unit. -- end note ]
7887  case TSK_ExplicitInstantiationDeclaration:
7888    return GVA_AvailableExternally;
7889
7890  case TSK_ImplicitInstantiation:
7891    External = GVA_DiscardableODR;
7892    break;
7893  }
7894
7895  if (!FD->isInlined())
7896    return External;
7897
7898  if ((!Context.getLangOpts().CPlusPlus && !Context.getLangOpts().MSVCCompat &&
7899       !FD->hasAttr<DLLExportAttr>()) ||
7900      FD->hasAttr<GNUInlineAttr>()) {
7901    // FIXME: This doesn't match gcc's behavior for dllexport inline functions.
7902
7903    // GNU or C99 inline semantics. Determine whether this symbol should be
7904    // externally visible.
7905    if (FD->isInlineDefinitionExternallyVisible())
7906      return External;
7907
7908    // C99 inline semantics, where the symbol is not externally visible.
7909    return GVA_AvailableExternally;
7910  }
7911
7912  // Functions specified with extern and inline in -fms-compatibility mode
7913  // forcibly get emitted.  While the body of the function cannot be later
7914  // replaced, the function definition cannot be discarded.
7915  if (FD->isMSExternInline())
7916    return GVA_StrongODR;
7917
7918  return GVA_DiscardableODR;
7919}
7920
7921static GVALinkage adjustGVALinkageForDLLAttribute(GVALinkage L, const Decl *D) {
7922  // See http://msdn.microsoft.com/en-us/library/xa0d9ste.aspx
7923  // dllexport/dllimport on inline functions.
7924  if (D->hasAttr<DLLImportAttr>()) {
7925    if (L == GVA_DiscardableODR || L == GVA_StrongODR)
7926      return GVA_AvailableExternally;
7927  } else if (D->hasAttr<DLLExportAttr>()) {
7928    if (L == GVA_DiscardableODR)
7929      return GVA_StrongODR;
7930  }
7931  return L;
7932}
7933
7934GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) const {
7935  return adjustGVALinkageForDLLAttribute(basicGVALinkageForFunction(*this, FD),
7936                                         FD);
7937}
7938
7939static GVALinkage basicGVALinkageForVariable(const ASTContext &Context,
7940                                             const VarDecl *VD) {
7941  if (!VD->isExternallyVisible())
7942    return GVA_Internal;
7943
7944  if (VD->isStaticLocal()) {
7945    GVALinkage StaticLocalLinkage = GVA_DiscardableODR;
7946    const DeclContext *LexicalContext = VD->getParentFunctionOrMethod();
7947    while (LexicalContext && !isa<FunctionDecl>(LexicalContext))
7948      LexicalContext = LexicalContext->getLexicalParent();
7949
7950    // Let the static local variable inherit its linkage from the nearest
7951    // enclosing function.
7952    if (LexicalContext)
7953      StaticLocalLinkage =
7954          Context.GetGVALinkageForFunction(cast<FunctionDecl>(LexicalContext));
7955
7956    // GVA_StrongODR function linkage is stronger than what we need,
7957    // downgrade to GVA_DiscardableODR.
7958    // This allows us to discard the variable if we never end up needing it.
7959    return StaticLocalLinkage == GVA_StrongODR ? GVA_DiscardableODR
7960                                               : StaticLocalLinkage;
7961  }
7962
7963  // MSVC treats in-class initialized static data members as definitions.
7964  // By giving them non-strong linkage, out-of-line definitions won't
7965  // cause link errors.
7966  if (Context.isMSStaticDataMemberInlineDefinition(VD))
7967    return GVA_DiscardableODR;
7968
7969  switch (VD->getTemplateSpecializationKind()) {
7970  case TSK_Undeclared:
7971  case TSK_ExplicitSpecialization:
7972    return GVA_StrongExternal;
7973
7974  case TSK_ExplicitInstantiationDefinition:
7975    return GVA_StrongODR;
7976
7977  case TSK_ExplicitInstantiationDeclaration:
7978    return GVA_AvailableExternally;
7979
7980  case TSK_ImplicitInstantiation:
7981    return GVA_DiscardableODR;
7982  }
7983
7984  llvm_unreachable("Invalid Linkage!");
7985}
7986
7987GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
7988  return adjustGVALinkageForDLLAttribute(basicGVALinkageForVariable(*this, VD),
7989                                         VD);
7990}
7991
7992bool ASTContext::DeclMustBeEmitted(const Decl *D) {
7993  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
7994    if (!VD->isFileVarDecl())
7995      return false;
7996    // Global named register variables (GNU extension) are never emitted.
7997    if (VD->getStorageClass() == SC_Register)
7998      return false;
7999  } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
8000    // We never need to emit an uninstantiated function template.
8001    if (FD->getTemplatedKind() == FunctionDecl::TK_FunctionTemplate)
8002      return false;
8003  } else if (isa<OMPThreadPrivateDecl>(D))
8004    return true;
8005  else
8006    return false;
8007
8008  // If this is a member of a class template, we do not need to emit it.
8009  if (D->getDeclContext()->isDependentContext())
8010    return false;
8011
8012  // Weak references don't produce any output by themselves.
8013  if (D->hasAttr<WeakRefAttr>())
8014    return false;
8015
8016  // Aliases and used decls are required.
8017  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
8018    return true;
8019
8020  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
8021    // Forward declarations aren't required.
8022    if (!FD->doesThisDeclarationHaveABody())
8023      return FD->doesDeclarationForceExternallyVisibleDefinition();
8024
8025    // Constructors and destructors are required.
8026    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
8027      return true;
8028
8029    // The key function for a class is required.  This rule only comes
8030    // into play when inline functions can be key functions, though.
8031    if (getTargetInfo().getCXXABI().canKeyFunctionBeInline()) {
8032      if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
8033        const CXXRecordDecl *RD = MD->getParent();
8034        if (MD->isOutOfLine() && RD->isDynamicClass()) {
8035          const CXXMethodDecl *KeyFunc = getCurrentKeyFunction(RD);
8036          if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
8037            return true;
8038        }
8039      }
8040    }
8041
8042    GVALinkage Linkage = GetGVALinkageForFunction(FD);
8043
8044    // static, static inline, always_inline, and extern inline functions can
8045    // always be deferred.  Normal inline functions can be deferred in C99/C++.
8046    // Implicit template instantiations can also be deferred in C++.
8047    if (Linkage == GVA_Internal || Linkage == GVA_AvailableExternally ||
8048        Linkage == GVA_DiscardableODR)
8049      return false;
8050    return true;
8051  }
8052
8053  const VarDecl *VD = cast<VarDecl>(D);
8054  assert(VD->isFileVarDecl() && "Expected file scoped var");
8055
8056  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly &&
8057      !isMSStaticDataMemberInlineDefinition(VD))
8058    return false;
8059
8060  // Variables that can be needed in other TUs are required.
8061  GVALinkage L = GetGVALinkageForVariable(VD);
8062  if (L != GVA_Internal && L != GVA_AvailableExternally &&
8063      L != GVA_DiscardableODR)
8064    return true;
8065
8066  // Variables that have destruction with side-effects are required.
8067  if (VD->getType().isDestructedType())
8068    return true;
8069
8070  // Variables that have initialization with side-effects are required.
8071  if (VD->getInit() && VD->getInit()->HasSideEffects(*this))
8072    return true;
8073
8074  return false;
8075}
8076
8077CallingConv ASTContext::getDefaultCallingConvention(bool IsVariadic,
8078                                                    bool IsCXXMethod) const {
8079  // Pass through to the C++ ABI object
8080  if (IsCXXMethod)
8081    return ABI->getDefaultMethodCallConv(IsVariadic);
8082
8083  if (LangOpts.MRTD && !IsVariadic) return CC_X86StdCall;
8084
8085  return Target->getDefaultCallingConv(TargetInfo::CCMT_Unknown);
8086}
8087
8088bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
8089  // Pass through to the C++ ABI object
8090  return ABI->isNearlyEmpty(RD);
8091}
8092
8093VTableContextBase *ASTContext::getVTableContext() {
8094  if (!VTContext.get()) {
8095    if (Target->getCXXABI().isMicrosoft())
8096      VTContext.reset(new MicrosoftVTableContext(*this));
8097    else
8098      VTContext.reset(new ItaniumVTableContext(*this));
8099  }
8100  return VTContext.get();
8101}
8102
8103MangleContext *ASTContext::createMangleContext() {
8104  switch (Target->getCXXABI().getKind()) {
8105  case TargetCXXABI::GenericAArch64:
8106  case TargetCXXABI::GenericItanium:
8107  case TargetCXXABI::GenericARM:
8108  case TargetCXXABI::GenericMIPS:
8109  case TargetCXXABI::iOS:
8110  case TargetCXXABI::iOS64:
8111    return ItaniumMangleContext::create(*this, getDiagnostics());
8112  case TargetCXXABI::Microsoft:
8113    return MicrosoftMangleContext::create(*this, getDiagnostics());
8114  }
8115  llvm_unreachable("Unsupported ABI");
8116}
8117
8118CXXABI::~CXXABI() {}
8119
8120size_t ASTContext::getSideTableAllocatedMemory() const {
8121  return ASTRecordLayouts.getMemorySize() +
8122         llvm::capacity_in_bytes(ObjCLayouts) +
8123         llvm::capacity_in_bytes(KeyFunctions) +
8124         llvm::capacity_in_bytes(ObjCImpls) +
8125         llvm::capacity_in_bytes(BlockVarCopyInits) +
8126         llvm::capacity_in_bytes(DeclAttrs) +
8127         llvm::capacity_in_bytes(TemplateOrInstantiation) +
8128         llvm::capacity_in_bytes(InstantiatedFromUsingDecl) +
8129         llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl) +
8130         llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl) +
8131         llvm::capacity_in_bytes(OverriddenMethods) +
8132         llvm::capacity_in_bytes(Types) +
8133         llvm::capacity_in_bytes(VariableArrayTypes) +
8134         llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
8135}
8136
8137/// getIntTypeForBitwidth -
8138/// sets integer QualTy according to specified details:
8139/// bitwidth, signed/unsigned.
8140/// Returns empty type if there is no appropriate target types.
8141QualType ASTContext::getIntTypeForBitwidth(unsigned DestWidth,
8142                                           unsigned Signed) const {
8143  TargetInfo::IntType Ty = getTargetInfo().getIntTypeByWidth(DestWidth, Signed);
8144  CanQualType QualTy = getFromTargetType(Ty);
8145  if (!QualTy && DestWidth == 128)
8146    return Signed ? Int128Ty : UnsignedInt128Ty;
8147  return QualTy;
8148}
8149
8150/// getRealTypeForBitwidth -
8151/// sets floating point QualTy according to specified bitwidth.
8152/// Returns empty type if there is no appropriate target types.
8153QualType ASTContext::getRealTypeForBitwidth(unsigned DestWidth) const {
8154  TargetInfo::RealType Ty = getTargetInfo().getRealTypeByWidth(DestWidth);
8155  switch (Ty) {
8156  case TargetInfo::Float:
8157    return FloatTy;
8158  case TargetInfo::Double:
8159    return DoubleTy;
8160  case TargetInfo::LongDouble:
8161    return LongDoubleTy;
8162  case TargetInfo::NoFloat:
8163    return QualType();
8164  }
8165
8166  llvm_unreachable("Unhandled TargetInfo::RealType value");
8167}
8168
8169void ASTContext::setManglingNumber(const NamedDecl *ND, unsigned Number) {
8170  if (Number > 1)
8171    MangleNumbers[ND] = Number;
8172}
8173
8174unsigned ASTContext::getManglingNumber(const NamedDecl *ND) const {
8175  llvm::DenseMap<const NamedDecl *, unsigned>::const_iterator I =
8176    MangleNumbers.find(ND);
8177  return I != MangleNumbers.end() ? I->second : 1;
8178}
8179
8180void ASTContext::setStaticLocalNumber(const VarDecl *VD, unsigned Number) {
8181  if (Number > 1)
8182    StaticLocalNumbers[VD] = Number;
8183}
8184
8185unsigned ASTContext::getStaticLocalNumber(const VarDecl *VD) const {
8186  llvm::DenseMap<const VarDecl *, unsigned>::const_iterator I =
8187      StaticLocalNumbers.find(VD);
8188  return I != StaticLocalNumbers.end() ? I->second : 1;
8189}
8190
8191MangleNumberingContext &
8192ASTContext::getManglingNumberContext(const DeclContext *DC) {
8193  assert(LangOpts.CPlusPlus);  // We don't need mangling numbers for plain C.
8194  MangleNumberingContext *&MCtx = MangleNumberingContexts[DC];
8195  if (!MCtx)
8196    MCtx = createMangleNumberingContext();
8197  return *MCtx;
8198}
8199
8200MangleNumberingContext *ASTContext::createMangleNumberingContext() const {
8201  return ABI->createMangleNumberingContext();
8202}
8203
8204const CXXConstructorDecl *
8205ASTContext::getCopyConstructorForExceptionObject(CXXRecordDecl *RD) {
8206  return ABI->getCopyConstructorForExceptionObject(
8207      cast<CXXRecordDecl>(RD->getFirstDecl()));
8208}
8209
8210void ASTContext::addCopyConstructorForExceptionObject(CXXRecordDecl *RD,
8211                                                      CXXConstructorDecl *CD) {
8212  return ABI->addCopyConstructorForExceptionObject(
8213      cast<CXXRecordDecl>(RD->getFirstDecl()),
8214      cast<CXXConstructorDecl>(CD->getFirstDecl()));
8215}
8216
8217void ASTContext::addDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
8218                                                 unsigned ParmIdx, Expr *DAE) {
8219  ABI->addDefaultArgExprForConstructor(
8220      cast<CXXConstructorDecl>(CD->getFirstDecl()), ParmIdx, DAE);
8221}
8222
8223Expr *ASTContext::getDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
8224                                                  unsigned ParmIdx) {
8225  return ABI->getDefaultArgExprForConstructor(
8226      cast<CXXConstructorDecl>(CD->getFirstDecl()), ParmIdx);
8227}
8228
8229void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
8230  ParamIndices[D] = index;
8231}
8232
8233unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
8234  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
8235  assert(I != ParamIndices.end() &&
8236         "ParmIndices lacks entry set by ParmVarDecl");
8237  return I->second;
8238}
8239
8240APValue *
8241ASTContext::getMaterializedTemporaryValue(const MaterializeTemporaryExpr *E,
8242                                          bool MayCreate) {
8243  assert(E && E->getStorageDuration() == SD_Static &&
8244         "don't need to cache the computed value for this temporary");
8245  if (MayCreate)
8246    return &MaterializedTemporaryValues[E];
8247
8248  llvm::DenseMap<const MaterializeTemporaryExpr *, APValue>::iterator I =
8249      MaterializedTemporaryValues.find(E);
8250  return I == MaterializedTemporaryValues.end() ? nullptr : &I->second;
8251}
8252
8253bool ASTContext::AtomicUsesUnsupportedLibcall(const AtomicExpr *E) const {
8254  const llvm::Triple &T = getTargetInfo().getTriple();
8255  if (!T.isOSDarwin())
8256    return false;
8257
8258  if (!(T.isiOS() && T.isOSVersionLT(7)) &&
8259      !(T.isMacOSX() && T.isOSVersionLT(10, 9)))
8260    return false;
8261
8262  QualType AtomicTy = E->getPtr()->getType()->getPointeeType();
8263  CharUnits sizeChars = getTypeSizeInChars(AtomicTy);
8264  uint64_t Size = sizeChars.getQuantity();
8265  CharUnits alignChars = getTypeAlignInChars(AtomicTy);
8266  unsigned Align = alignChars.getQuantity();
8267  unsigned MaxInlineWidthInBits = getTargetInfo().getMaxAtomicInlineWidth();
8268  return (Size != Align || toBits(sizeChars) > MaxInlineWidthInBits);
8269}
8270
8271namespace {
8272
8273  /// \brief A \c RecursiveASTVisitor that builds a map from nodes to their
8274  /// parents as defined by the \c RecursiveASTVisitor.
8275  ///
8276  /// Note that the relationship described here is purely in terms of AST
8277  /// traversal - there are other relationships (for example declaration context)
8278  /// in the AST that are better modeled by special matchers.
8279  ///
8280  /// FIXME: Currently only builds up the map using \c Stmt and \c Decl nodes.
8281  class ParentMapASTVisitor : public RecursiveASTVisitor<ParentMapASTVisitor> {
8282
8283  public:
8284    /// \brief Builds and returns the translation unit's parent map.
8285    ///
8286    ///  The caller takes ownership of the returned \c ParentMap.
8287    static ASTContext::ParentMap *buildMap(TranslationUnitDecl &TU) {
8288      ParentMapASTVisitor Visitor(new ASTContext::ParentMap);
8289      Visitor.TraverseDecl(&TU);
8290      return Visitor.Parents;
8291    }
8292
8293  private:
8294    typedef RecursiveASTVisitor<ParentMapASTVisitor> VisitorBase;
8295
8296    ParentMapASTVisitor(ASTContext::ParentMap *Parents) : Parents(Parents) {
8297    }
8298
8299    bool shouldVisitTemplateInstantiations() const {
8300      return true;
8301    }
8302    bool shouldVisitImplicitCode() const {
8303      return true;
8304    }
8305    // Disables data recursion. We intercept Traverse* methods in the RAV, which
8306    // are not triggered during data recursion.
8307    bool shouldUseDataRecursionFor(clang::Stmt *S) const {
8308      return false;
8309    }
8310
8311    template <typename T>
8312    bool TraverseNode(T *Node, bool(VisitorBase:: *traverse) (T *)) {
8313      if (!Node)
8314        return true;
8315      if (ParentStack.size() > 0) {
8316        // FIXME: Currently we add the same parent multiple times, but only
8317        // when no memoization data is available for the type.
8318        // For example when we visit all subexpressions of template
8319        // instantiations; this is suboptimal, but benign: the only way to
8320        // visit those is with hasAncestor / hasParent, and those do not create
8321        // new matches.
8322        // The plan is to enable DynTypedNode to be storable in a map or hash
8323        // map. The main problem there is to implement hash functions /
8324        // comparison operators for all types that DynTypedNode supports that
8325        // do not have pointer identity.
8326        auto &NodeOrVector = (*Parents)[Node];
8327        if (NodeOrVector.isNull()) {
8328          NodeOrVector = new ast_type_traits::DynTypedNode(ParentStack.back());
8329        } else {
8330          if (NodeOrVector.template is<ast_type_traits::DynTypedNode *>()) {
8331            auto *Node =
8332                NodeOrVector.template get<ast_type_traits::DynTypedNode *>();
8333            auto *Vector = new ASTContext::ParentVector(1, *Node);
8334            NodeOrVector = Vector;
8335            delete Node;
8336          }
8337          assert(NodeOrVector.template is<ASTContext::ParentVector *>());
8338
8339          auto *Vector =
8340              NodeOrVector.template get<ASTContext::ParentVector *>();
8341          // Skip duplicates for types that have memoization data.
8342          // We must check that the type has memoization data before calling
8343          // std::find() because DynTypedNode::operator== can't compare all
8344          // types.
8345          bool Found = ParentStack.back().getMemoizationData() &&
8346                       std::find(Vector->begin(), Vector->end(),
8347                                 ParentStack.back()) != Vector->end();
8348          if (!Found)
8349            Vector->push_back(ParentStack.back());
8350        }
8351      }
8352      ParentStack.push_back(ast_type_traits::DynTypedNode::create(*Node));
8353      bool Result = (this ->* traverse) (Node);
8354      ParentStack.pop_back();
8355      return Result;
8356    }
8357
8358    bool TraverseDecl(Decl *DeclNode) {
8359      return TraverseNode(DeclNode, &VisitorBase::TraverseDecl);
8360    }
8361
8362    bool TraverseStmt(Stmt *StmtNode) {
8363      return TraverseNode(StmtNode, &VisitorBase::TraverseStmt);
8364    }
8365
8366    ASTContext::ParentMap *Parents;
8367    llvm::SmallVector<ast_type_traits::DynTypedNode, 16> ParentStack;
8368
8369    friend class RecursiveASTVisitor<ParentMapASTVisitor>;
8370  };
8371
8372} // end namespace
8373
8374ArrayRef<ast_type_traits::DynTypedNode>
8375ASTContext::getParents(const ast_type_traits::DynTypedNode &Node) {
8376  assert(Node.getMemoizationData() &&
8377         "Invariant broken: only nodes that support memoization may be "
8378         "used in the parent map.");
8379  if (!AllParents) {
8380    // We always need to run over the whole translation unit, as
8381    // hasAncestor can escape any subtree.
8382    AllParents.reset(
8383        ParentMapASTVisitor::buildMap(*getTranslationUnitDecl()));
8384  }
8385  ParentMap::const_iterator I = AllParents->find(Node.getMemoizationData());
8386  if (I == AllParents->end()) {
8387    return None;
8388  }
8389  if (auto *N = I->second.dyn_cast<ast_type_traits::DynTypedNode *>()) {
8390    return llvm::makeArrayRef(N, 1);
8391  }
8392  return *I->second.get<ParentVector *>();
8393}
8394
8395bool
8396ASTContext::ObjCMethodsAreEqual(const ObjCMethodDecl *MethodDecl,
8397                                const ObjCMethodDecl *MethodImpl) {
8398  // No point trying to match an unavailable/deprecated mothod.
8399  if (MethodDecl->hasAttr<UnavailableAttr>()
8400      || MethodDecl->hasAttr<DeprecatedAttr>())
8401    return false;
8402  if (MethodDecl->getObjCDeclQualifier() !=
8403      MethodImpl->getObjCDeclQualifier())
8404    return false;
8405  if (!hasSameType(MethodDecl->getReturnType(), MethodImpl->getReturnType()))
8406    return false;
8407
8408  if (MethodDecl->param_size() != MethodImpl->param_size())
8409    return false;
8410
8411  for (ObjCMethodDecl::param_const_iterator IM = MethodImpl->param_begin(),
8412       IF = MethodDecl->param_begin(), EM = MethodImpl->param_end(),
8413       EF = MethodDecl->param_end();
8414       IM != EM && IF != EF; ++IM, ++IF) {
8415    const ParmVarDecl *DeclVar = (*IF);
8416    const ParmVarDecl *ImplVar = (*IM);
8417    if (ImplVar->getObjCDeclQualifier() != DeclVar->getObjCDeclQualifier())
8418      return false;
8419    if (!hasSameType(DeclVar->getType(), ImplVar->getType()))
8420      return false;
8421  }
8422  return (MethodDecl->isVariadic() == MethodImpl->isVariadic());
8423
8424}
8425
8426// Explicitly instantiate this in case a Redeclarable<T> is used from a TU that
8427// doesn't include ASTContext.h
8428template
8429clang::LazyGenerationalUpdatePtr<
8430    const Decl *, Decl *, &ExternalASTSource::CompleteRedeclChain>::ValueType
8431clang::LazyGenerationalUpdatePtr<
8432    const Decl *, Decl *, &ExternalASTSource::CompleteRedeclChain>::makeValue(
8433        const clang::ASTContext &Ctx, Decl *Value);
8434