ASTContext.cpp revision 11f22a35b7f08a8d017f6ab26e440edffc930f96 
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/Basic/Builtins.h"
33#include "clang/Basic/SourceManager.h"
34#include "clang/Basic/TargetInfo.h"
35#include "llvm/ADT/SmallString.h"
36#include "llvm/ADT/StringExtras.h"
37#include "llvm/Support/Capacity.h"
38#include "llvm/Support/MathExtras.h"
39#include "llvm/Support/raw_ostream.h"
40#include <map>
41
42using namespace clang;
43
44unsigned ASTContext::NumImplicitDefaultConstructors;
45unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
46unsigned ASTContext::NumImplicitCopyConstructors;
47unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
48unsigned ASTContext::NumImplicitMoveConstructors;
49unsigned ASTContext::NumImplicitMoveConstructorsDeclared;
50unsigned ASTContext::NumImplicitCopyAssignmentOperators;
51unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
52unsigned ASTContext::NumImplicitMoveAssignmentOperators;
53unsigned ASTContext::NumImplicitMoveAssignmentOperatorsDeclared;
54unsigned ASTContext::NumImplicitDestructors;
55unsigned ASTContext::NumImplicitDestructorsDeclared;
56
57enum FloatingRank {
58  HalfRank, FloatRank, DoubleRank, LongDoubleRank
59};
60
61RawComment *ASTContext::getRawCommentForDeclNoCache(const Decl *D) const {
62  if (!CommentsLoaded && ExternalSource) {
63    ExternalSource->ReadComments();
64    CommentsLoaded = true;
65  }
66
67  assert(D);
68
69  // User can not attach documentation to implicit declarations.
70  if (D->isImplicit())
71    return NULL;
72
73  // User can not attach documentation to implicit instantiations.
74  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
75    if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
76      return NULL;
77  }
78
79  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
80    if (VD->isStaticDataMember() &&
81        VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
82      return NULL;
83  }
84
85  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(D)) {
86    if (CRD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
87      return NULL;
88  }
89
90  if (const ClassTemplateSpecializationDecl *CTSD =
91          dyn_cast<ClassTemplateSpecializationDecl>(D)) {
92    TemplateSpecializationKind TSK = CTSD->getSpecializationKind();
93    if (TSK == TSK_ImplicitInstantiation ||
94        TSK == TSK_Undeclared)
95      return NULL;
96  }
97
98  if (const EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
99    if (ED->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
100      return NULL;
101  }
102  if (const TagDecl *TD = dyn_cast<TagDecl>(D)) {
103    // When tag declaration (but not definition!) is part of the
104    // decl-specifier-seq of some other declaration, it doesn't get comment
105    if (TD->isEmbeddedInDeclarator() && !TD->isCompleteDefinition())
106      return NULL;
107  }
108  // TODO: handle comments for function parameters properly.
109  if (isa<ParmVarDecl>(D))
110    return NULL;
111
112  // TODO: we could look up template parameter documentation in the template
113  // documentation.
114  if (isa<TemplateTypeParmDecl>(D) ||
115      isa<NonTypeTemplateParmDecl>(D) ||
116      isa<TemplateTemplateParmDecl>(D))
117    return NULL;
118
119  ArrayRef<RawComment *> RawComments = Comments.getComments();
120
121  // If there are no comments anywhere, we won't find anything.
122  if (RawComments.empty())
123    return NULL;
124
125  // Find declaration location.
126  // For Objective-C declarations we generally don't expect to have multiple
127  // declarators, thus use declaration starting location as the "declaration
128  // location".
129  // For all other declarations multiple declarators are used quite frequently,
130  // so we use the location of the identifier as the "declaration location".
131  SourceLocation DeclLoc;
132  if (isa<ObjCMethodDecl>(D) || isa<ObjCContainerDecl>(D) ||
133      isa<ObjCPropertyDecl>(D) ||
134      isa<RedeclarableTemplateDecl>(D) ||
135      isa<ClassTemplateSpecializationDecl>(D))
136    DeclLoc = D->getLocStart();
137  else {
138    DeclLoc = D->getLocation();
139    // If location of the typedef name is in a macro, it is because being
140    // declared via a macro. Try using declaration's starting location
141    // as the "declaration location".
142    if (DeclLoc.isMacroID() && isa<TypedefDecl>(D))
143      DeclLoc = D->getLocStart();
144  }
145
146  // If the declaration doesn't map directly to a location in a file, we
147  // can't find the comment.
148  if (DeclLoc.isInvalid() || !DeclLoc.isFileID())
149    return NULL;
150
151  // Find the comment that occurs just after this declaration.
152  ArrayRef<RawComment *>::iterator Comment;
153  {
154    // When searching for comments during parsing, the comment we are looking
155    // for is usually among the last two comments we parsed -- check them
156    // first.
157    RawComment CommentAtDeclLoc(
158        SourceMgr, SourceRange(DeclLoc), false,
159        LangOpts.CommentOpts.ParseAllComments);
160    BeforeThanCompare<RawComment> Compare(SourceMgr);
161    ArrayRef<RawComment *>::iterator MaybeBeforeDecl = RawComments.end() - 1;
162    bool Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
163    if (!Found && RawComments.size() >= 2) {
164      MaybeBeforeDecl--;
165      Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
166    }
167
168    if (Found) {
169      Comment = MaybeBeforeDecl + 1;
170      assert(Comment == std::lower_bound(RawComments.begin(), RawComments.end(),
171                                         &CommentAtDeclLoc, Compare));
172    } else {
173      // Slow path.
174      Comment = std::lower_bound(RawComments.begin(), RawComments.end(),
175                                 &CommentAtDeclLoc, Compare);
176    }
177  }
178
179  // Decompose the location for the declaration and find the beginning of the
180  // file buffer.
181  std::pair<FileID, unsigned> DeclLocDecomp = SourceMgr.getDecomposedLoc(DeclLoc);
182
183  // First check whether we have a trailing comment.
184  if (Comment != RawComments.end() &&
185      (*Comment)->isDocumentation() && (*Comment)->isTrailingComment() &&
186      (isa<FieldDecl>(D) || isa<EnumConstantDecl>(D) || isa<VarDecl>(D) ||
187       isa<ObjCMethodDecl>(D) || isa<ObjCPropertyDecl>(D))) {
188    std::pair<FileID, unsigned> CommentBeginDecomp
189      = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getBegin());
190    // Check that Doxygen trailing comment comes after the declaration, starts
191    // on the same line and in the same file as the declaration.
192    if (DeclLocDecomp.first == CommentBeginDecomp.first &&
193        SourceMgr.getLineNumber(DeclLocDecomp.first, DeclLocDecomp.second)
194          == SourceMgr.getLineNumber(CommentBeginDecomp.first,
195                                     CommentBeginDecomp.second)) {
196      return *Comment;
197    }
198  }
199
200  // The comment just after the declaration was not a trailing comment.
201  // Let's look at the previous comment.
202  if (Comment == RawComments.begin())
203    return NULL;
204  --Comment;
205
206  // Check that we actually have a non-member Doxygen comment.
207  if (!(*Comment)->isDocumentation() || (*Comment)->isTrailingComment())
208    return NULL;
209
210  // Decompose the end of the comment.
211  std::pair<FileID, unsigned> CommentEndDecomp
212    = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getEnd());
213
214  // If the comment and the declaration aren't in the same file, then they
215  // aren't related.
216  if (DeclLocDecomp.first != CommentEndDecomp.first)
217    return NULL;
218
219  // Get the corresponding buffer.
220  bool Invalid = false;
221  const char *Buffer = SourceMgr.getBufferData(DeclLocDecomp.first,
222                                               &Invalid).data();
223  if (Invalid)
224    return NULL;
225
226  // Extract text between the comment and declaration.
227  StringRef Text(Buffer + CommentEndDecomp.second,
228                 DeclLocDecomp.second - CommentEndDecomp.second);
229
230  // There should be no other declarations or preprocessor directives between
231  // comment and declaration.
232  if (Text.find_first_of(";{}#@") != StringRef::npos)
233    return NULL;
234
235  return *Comment;
236}
237
238namespace {
239/// If we have a 'templated' declaration for a template, adjust 'D' to
240/// refer to the actual template.
241/// If we have an implicit instantiation, adjust 'D' to refer to template.
242const Decl *adjustDeclToTemplate(const Decl *D) {
243  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
244    // Is this function declaration part of a function template?
245    if (const FunctionTemplateDecl *FTD = FD->getDescribedFunctionTemplate())
246      return FTD;
247
248    // Nothing to do if function is not an implicit instantiation.
249    if (FD->getTemplateSpecializationKind() != TSK_ImplicitInstantiation)
250      return D;
251
252    // Function is an implicit instantiation of a function template?
253    if (const FunctionTemplateDecl *FTD = FD->getPrimaryTemplate())
254      return FTD;
255
256    // Function is instantiated from a member definition of a class template?
257    if (const FunctionDecl *MemberDecl =
258            FD->getInstantiatedFromMemberFunction())
259      return MemberDecl;
260
261    return D;
262  }
263  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
264    // Static data member is instantiated from a member definition of a class
265    // template?
266    if (VD->isStaticDataMember())
267      if (const VarDecl *MemberDecl = VD->getInstantiatedFromStaticDataMember())
268        return MemberDecl;
269
270    return D;
271  }
272  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(D)) {
273    // Is this class declaration part of a class template?
274    if (const ClassTemplateDecl *CTD = CRD->getDescribedClassTemplate())
275      return CTD;
276
277    // Class is an implicit instantiation of a class template or partial
278    // specialization?
279    if (const ClassTemplateSpecializationDecl *CTSD =
280            dyn_cast<ClassTemplateSpecializationDecl>(CRD)) {
281      if (CTSD->getSpecializationKind() != TSK_ImplicitInstantiation)
282        return D;
283      llvm::PointerUnion<ClassTemplateDecl *,
284                         ClassTemplatePartialSpecializationDecl *>
285          PU = CTSD->getSpecializedTemplateOrPartial();
286      return PU.is<ClassTemplateDecl*>() ?
287          static_cast<const Decl*>(PU.get<ClassTemplateDecl *>()) :
288          static_cast<const Decl*>(
289              PU.get<ClassTemplatePartialSpecializationDecl *>());
290    }
291
292    // Class is instantiated from a member definition of a class template?
293    if (const MemberSpecializationInfo *Info =
294                   CRD->getMemberSpecializationInfo())
295      return Info->getInstantiatedFrom();
296
297    return D;
298  }
299  if (const EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
300    // Enum is instantiated from a member definition of a class template?
301    if (const EnumDecl *MemberDecl = ED->getInstantiatedFromMemberEnum())
302      return MemberDecl;
303
304    return D;
305  }
306  // FIXME: Adjust alias templates?
307  return D;
308}
309} // unnamed namespace
310
311const RawComment *ASTContext::getRawCommentForAnyRedecl(
312                                                const Decl *D,
313                                                const Decl **OriginalDecl) const {
314  D = adjustDeclToTemplate(D);
315
316  // Check whether we have cached a comment for this declaration already.
317  {
318    llvm::DenseMap<const Decl *, RawCommentAndCacheFlags>::iterator Pos =
319        RedeclComments.find(D);
320    if (Pos != RedeclComments.end()) {
321      const RawCommentAndCacheFlags &Raw = Pos->second;
322      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
323        if (OriginalDecl)
324          *OriginalDecl = Raw.getOriginalDecl();
325        return Raw.getRaw();
326      }
327    }
328  }
329
330  // Search for comments attached to declarations in the redeclaration chain.
331  const RawComment *RC = NULL;
332  const Decl *OriginalDeclForRC = NULL;
333  for (Decl::redecl_iterator I = D->redecls_begin(),
334                             E = D->redecls_end();
335       I != E; ++I) {
336    llvm::DenseMap<const Decl *, RawCommentAndCacheFlags>::iterator Pos =
337        RedeclComments.find(*I);
338    if (Pos != RedeclComments.end()) {
339      const RawCommentAndCacheFlags &Raw = Pos->second;
340      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
341        RC = Raw.getRaw();
342        OriginalDeclForRC = Raw.getOriginalDecl();
343        break;
344      }
345    } else {
346      RC = getRawCommentForDeclNoCache(*I);
347      OriginalDeclForRC = *I;
348      RawCommentAndCacheFlags Raw;
349      if (RC) {
350        Raw.setRaw(RC);
351        Raw.setKind(RawCommentAndCacheFlags::FromDecl);
352      } else
353        Raw.setKind(RawCommentAndCacheFlags::NoCommentInDecl);
354      Raw.setOriginalDecl(*I);
355      RedeclComments[*I] = Raw;
356      if (RC)
357        break;
358    }
359  }
360
361  // If we found a comment, it should be a documentation comment.
362  assert(!RC || RC->isDocumentation());
363
364  if (OriginalDecl)
365    *OriginalDecl = OriginalDeclForRC;
366
367  // Update cache for every declaration in the redeclaration chain.
368  RawCommentAndCacheFlags Raw;
369  Raw.setRaw(RC);
370  Raw.setKind(RawCommentAndCacheFlags::FromRedecl);
371  Raw.setOriginalDecl(OriginalDeclForRC);
372
373  for (Decl::redecl_iterator I = D->redecls_begin(),
374                             E = D->redecls_end();
375       I != E; ++I) {
376    RawCommentAndCacheFlags &R = RedeclComments[*I];
377    if (R.getKind() == RawCommentAndCacheFlags::NoCommentInDecl)
378      R = Raw;
379  }
380
381  return RC;
382}
383
384static void addRedeclaredMethods(const ObjCMethodDecl *ObjCMethod,
385                   SmallVectorImpl<const NamedDecl *> &Redeclared) {
386  const DeclContext *DC = ObjCMethod->getDeclContext();
387  if (const ObjCImplDecl *IMD = dyn_cast<ObjCImplDecl>(DC)) {
388    const ObjCInterfaceDecl *ID = IMD->getClassInterface();
389    if (!ID)
390      return;
391    // Add redeclared method here.
392    for (ObjCInterfaceDecl::known_extensions_iterator
393           Ext = ID->known_extensions_begin(),
394           ExtEnd = ID->known_extensions_end();
395         Ext != ExtEnd; ++Ext) {
396      if (ObjCMethodDecl *RedeclaredMethod =
397            Ext->getMethod(ObjCMethod->getSelector(),
398                                  ObjCMethod->isInstanceMethod()))
399        Redeclared.push_back(RedeclaredMethod);
400    }
401  }
402}
403
404comments::FullComment *ASTContext::cloneFullComment(comments::FullComment *FC,
405                                                    const Decl *D) const {
406  comments::DeclInfo *ThisDeclInfo = new (*this) comments::DeclInfo;
407  ThisDeclInfo->CommentDecl = D;
408  ThisDeclInfo->IsFilled = false;
409  ThisDeclInfo->fill();
410  ThisDeclInfo->CommentDecl = FC->getDecl();
411  comments::FullComment *CFC =
412    new (*this) comments::FullComment(FC->getBlocks(),
413                                      ThisDeclInfo);
414  return CFC;
415
416}
417
418comments::FullComment *ASTContext::getLocalCommentForDeclUncached(const Decl *D) const {
419  const RawComment *RC = getRawCommentForDeclNoCache(D);
420  return RC ? RC->parse(*this, 0, D) : 0;
421}
422
423comments::FullComment *ASTContext::getCommentForDecl(
424                                              const Decl *D,
425                                              const Preprocessor *PP) const {
426  if (D->isInvalidDecl())
427    return NULL;
428  D = adjustDeclToTemplate(D);
429
430  const Decl *Canonical = D->getCanonicalDecl();
431  llvm::DenseMap<const Decl *, comments::FullComment *>::iterator Pos =
432      ParsedComments.find(Canonical);
433
434  if (Pos != ParsedComments.end()) {
435    if (Canonical != D) {
436      comments::FullComment *FC = Pos->second;
437      comments::FullComment *CFC = cloneFullComment(FC, D);
438      return CFC;
439    }
440    return Pos->second;
441  }
442
443  const Decl *OriginalDecl;
444
445  const RawComment *RC = getRawCommentForAnyRedecl(D, &OriginalDecl);
446  if (!RC) {
447    if (isa<ObjCMethodDecl>(D) || isa<FunctionDecl>(D)) {
448      SmallVector<const NamedDecl*, 8> Overridden;
449      const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D);
450      if (OMD && OMD->isPropertyAccessor())
451        if (const ObjCPropertyDecl *PDecl = OMD->findPropertyDecl())
452          if (comments::FullComment *FC = getCommentForDecl(PDecl, PP))
453            return cloneFullComment(FC, D);
454      if (OMD)
455        addRedeclaredMethods(OMD, Overridden);
456      getOverriddenMethods(dyn_cast<NamedDecl>(D), Overridden);
457      for (unsigned i = 0, e = Overridden.size(); i < e; i++)
458        if (comments::FullComment *FC = getCommentForDecl(Overridden[i], PP))
459          return cloneFullComment(FC, D);
460    }
461    else if (const TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(D)) {
462      // Attach any tag type's documentation to its typedef if latter
463      // does not have one of its own.
464      QualType QT = TD->getUnderlyingType();
465      if (const TagType *TT = QT->getAs<TagType>())
466        if (const Decl *TD = TT->getDecl())
467          if (comments::FullComment *FC = getCommentForDecl(TD, PP))
468            return cloneFullComment(FC, D);
469    }
470    else if (const ObjCInterfaceDecl *IC = dyn_cast<ObjCInterfaceDecl>(D)) {
471      while (IC->getSuperClass()) {
472        IC = IC->getSuperClass();
473        if (comments::FullComment *FC = getCommentForDecl(IC, PP))
474          return cloneFullComment(FC, D);
475      }
476    }
477    else if (const ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(D)) {
478      if (const ObjCInterfaceDecl *IC = CD->getClassInterface())
479        if (comments::FullComment *FC = getCommentForDecl(IC, PP))
480          return cloneFullComment(FC, D);
481    }
482    else if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D)) {
483      if (!(RD = RD->getDefinition()))
484        return NULL;
485      // Check non-virtual bases.
486      for (CXXRecordDecl::base_class_const_iterator I =
487           RD->bases_begin(), E = RD->bases_end(); I != E; ++I) {
488        if (I->isVirtual() || (I->getAccessSpecifier() != AS_public))
489          continue;
490        QualType Ty = I->getType();
491        if (Ty.isNull())
492          continue;
493        if (const CXXRecordDecl *NonVirtualBase = Ty->getAsCXXRecordDecl()) {
494          if (!(NonVirtualBase= NonVirtualBase->getDefinition()))
495            continue;
496
497          if (comments::FullComment *FC = getCommentForDecl((NonVirtualBase), PP))
498            return cloneFullComment(FC, D);
499        }
500      }
501      // Check virtual bases.
502      for (CXXRecordDecl::base_class_const_iterator I =
503           RD->vbases_begin(), E = RD->vbases_end(); I != E; ++I) {
504        if (I->getAccessSpecifier() != AS_public)
505          continue;
506        QualType Ty = I->getType();
507        if (Ty.isNull())
508          continue;
509        if (const CXXRecordDecl *VirtualBase = Ty->getAsCXXRecordDecl()) {
510          if (!(VirtualBase= VirtualBase->getDefinition()))
511            continue;
512          if (comments::FullComment *FC = getCommentForDecl((VirtualBase), PP))
513            return cloneFullComment(FC, D);
514        }
515      }
516    }
517    return NULL;
518  }
519
520  // If the RawComment was attached to other redeclaration of this Decl, we
521  // should parse the comment in context of that other Decl.  This is important
522  // because comments can contain references to parameter names which can be
523  // different across redeclarations.
524  if (D != OriginalDecl)
525    return getCommentForDecl(OriginalDecl, PP);
526
527  comments::FullComment *FC = RC->parse(*this, PP, D);
528  ParsedComments[Canonical] = FC;
529  return FC;
530}
531
532void
533ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
534                                               TemplateTemplateParmDecl *Parm) {
535  ID.AddInteger(Parm->getDepth());
536  ID.AddInteger(Parm->getPosition());
537  ID.AddBoolean(Parm->isParameterPack());
538
539  TemplateParameterList *Params = Parm->getTemplateParameters();
540  ID.AddInteger(Params->size());
541  for (TemplateParameterList::const_iterator P = Params->begin(),
542                                          PEnd = Params->end();
543       P != PEnd; ++P) {
544    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
545      ID.AddInteger(0);
546      ID.AddBoolean(TTP->isParameterPack());
547      continue;
548    }
549
550    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
551      ID.AddInteger(1);
552      ID.AddBoolean(NTTP->isParameterPack());
553      ID.AddPointer(NTTP->getType().getCanonicalType().getAsOpaquePtr());
554      if (NTTP->isExpandedParameterPack()) {
555        ID.AddBoolean(true);
556        ID.AddInteger(NTTP->getNumExpansionTypes());
557        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
558          QualType T = NTTP->getExpansionType(I);
559          ID.AddPointer(T.getCanonicalType().getAsOpaquePtr());
560        }
561      } else
562        ID.AddBoolean(false);
563      continue;
564    }
565
566    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
567    ID.AddInteger(2);
568    Profile(ID, TTP);
569  }
570}
571
572TemplateTemplateParmDecl *
573ASTContext::getCanonicalTemplateTemplateParmDecl(
574                                          TemplateTemplateParmDecl *TTP) const {
575  // Check if we already have a canonical template template parameter.
576  llvm::FoldingSetNodeID ID;
577  CanonicalTemplateTemplateParm::Profile(ID, TTP);
578  void *InsertPos = 0;
579  CanonicalTemplateTemplateParm *Canonical
580    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
581  if (Canonical)
582    return Canonical->getParam();
583
584  // Build a canonical template parameter list.
585  TemplateParameterList *Params = TTP->getTemplateParameters();
586  SmallVector<NamedDecl *, 4> CanonParams;
587  CanonParams.reserve(Params->size());
588  for (TemplateParameterList::const_iterator P = Params->begin(),
589                                          PEnd = Params->end();
590       P != PEnd; ++P) {
591    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
592      CanonParams.push_back(
593                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
594                                               SourceLocation(),
595                                               SourceLocation(),
596                                               TTP->getDepth(),
597                                               TTP->getIndex(), 0, false,
598                                               TTP->isParameterPack()));
599    else if (NonTypeTemplateParmDecl *NTTP
600             = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
601      QualType T = getCanonicalType(NTTP->getType());
602      TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
603      NonTypeTemplateParmDecl *Param;
604      if (NTTP->isExpandedParameterPack()) {
605        SmallVector<QualType, 2> ExpandedTypes;
606        SmallVector<TypeSourceInfo *, 2> ExpandedTInfos;
607        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
608          ExpandedTypes.push_back(getCanonicalType(NTTP->getExpansionType(I)));
609          ExpandedTInfos.push_back(
610                                getTrivialTypeSourceInfo(ExpandedTypes.back()));
611        }
612
613        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
614                                                SourceLocation(),
615                                                SourceLocation(),
616                                                NTTP->getDepth(),
617                                                NTTP->getPosition(), 0,
618                                                T,
619                                                TInfo,
620                                                ExpandedTypes.data(),
621                                                ExpandedTypes.size(),
622                                                ExpandedTInfos.data());
623      } else {
624        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
625                                                SourceLocation(),
626                                                SourceLocation(),
627                                                NTTP->getDepth(),
628                                                NTTP->getPosition(), 0,
629                                                T,
630                                                NTTP->isParameterPack(),
631                                                TInfo);
632      }
633      CanonParams.push_back(Param);
634
635    } else
636      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
637                                           cast<TemplateTemplateParmDecl>(*P)));
638  }
639
640  TemplateTemplateParmDecl *CanonTTP
641    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
642                                       SourceLocation(), TTP->getDepth(),
643                                       TTP->getPosition(),
644                                       TTP->isParameterPack(),
645                                       0,
646                         TemplateParameterList::Create(*this, SourceLocation(),
647                                                       SourceLocation(),
648                                                       CanonParams.data(),
649                                                       CanonParams.size(),
650                                                       SourceLocation()));
651
652  // Get the new insert position for the node we care about.
653  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
654  assert(Canonical == 0 && "Shouldn't be in the map!");
655  (void)Canonical;
656
657  // Create the canonical template template parameter entry.
658  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
659  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
660  return CanonTTP;
661}
662
663CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
664  if (!LangOpts.CPlusPlus) return 0;
665
666  switch (T.getCXXABI().getKind()) {
667  case TargetCXXABI::GenericARM:
668  case TargetCXXABI::iOS:
669    return CreateARMCXXABI(*this);
670  case TargetCXXABI::GenericAArch64: // Same as Itanium at this level
671  case TargetCXXABI::GenericItanium:
672    return CreateItaniumCXXABI(*this);
673  case TargetCXXABI::Microsoft:
674    return CreateMicrosoftCXXABI(*this);
675  }
676  llvm_unreachable("Invalid CXXABI type!");
677}
678
679static const LangAS::Map *getAddressSpaceMap(const TargetInfo &T,
680                                             const LangOptions &LOpts) {
681  if (LOpts.FakeAddressSpaceMap) {
682    // The fake address space map must have a distinct entry for each
683    // language-specific address space.
684    static const unsigned FakeAddrSpaceMap[] = {
685      1, // opencl_global
686      2, // opencl_local
687      3, // opencl_constant
688      4, // cuda_device
689      5, // cuda_constant
690      6  // cuda_shared
691    };
692    return &FakeAddrSpaceMap;
693  } else {
694    return &T.getAddressSpaceMap();
695  }
696}
697
698static bool isAddrSpaceMapManglingEnabled(const TargetInfo &TI,
699                                          const LangOptions &LangOpts) {
700  switch (LangOpts.getAddressSpaceMapMangling()) {
701  case LangOptions::ASMM_Target:
702    return TI.useAddressSpaceMapMangling();
703  case LangOptions::ASMM_On:
704    return true;
705  case LangOptions::ASMM_Off:
706    return false;
707  }
708  llvm_unreachable("getAddressSpaceMapMangling() doesn't cover anything.");
709}
710
711ASTContext::ASTContext(LangOptions& LOpts, SourceManager &SM,
712                       const TargetInfo *t,
713                       IdentifierTable &idents, SelectorTable &sels,
714                       Builtin::Context &builtins,
715                       unsigned size_reserve,
716                       bool DelayInitialization)
717  : FunctionProtoTypes(this_()),
718    TemplateSpecializationTypes(this_()),
719    DependentTemplateSpecializationTypes(this_()),
720    SubstTemplateTemplateParmPacks(this_()),
721    GlobalNestedNameSpecifier(0),
722    Int128Decl(0), UInt128Decl(0), Float128StubDecl(0),
723    BuiltinVaListDecl(0),
724    ObjCIdDecl(0), ObjCSelDecl(0), ObjCClassDecl(0), ObjCProtocolClassDecl(0),
725    BOOLDecl(0),
726    CFConstantStringTypeDecl(0), ObjCInstanceTypeDecl(0),
727    FILEDecl(0),
728    jmp_bufDecl(0), sigjmp_bufDecl(0), ucontext_tDecl(0),
729    BlockDescriptorType(0), BlockDescriptorExtendedType(0),
730    cudaConfigureCallDecl(0),
731    NullTypeSourceInfo(QualType()),
732    FirstLocalImport(), LastLocalImport(),
733    SourceMgr(SM), LangOpts(LOpts),
734    AddrSpaceMap(0), Target(t), PrintingPolicy(LOpts),
735    Idents(idents), Selectors(sels),
736    BuiltinInfo(builtins),
737    DeclarationNames(*this),
738    ExternalSource(0), Listener(0),
739    Comments(SM), CommentsLoaded(false),
740    CommentCommandTraits(BumpAlloc, LOpts.CommentOpts),
741    LastSDM(0, 0)
742{
743  if (size_reserve > 0) Types.reserve(size_reserve);
744  TUDecl = TranslationUnitDecl::Create(*this);
745
746  if (!DelayInitialization) {
747    assert(t && "No target supplied for ASTContext initialization");
748    InitBuiltinTypes(*t);
749  }
750}
751
752ASTContext::~ASTContext() {
753  // Release the DenseMaps associated with DeclContext objects.
754  // FIXME: Is this the ideal solution?
755  ReleaseDeclContextMaps();
756
757  // Call all of the deallocation functions on all of their targets.
758  for (DeallocationMap::const_iterator I = Deallocations.begin(),
759           E = Deallocations.end(); I != E; ++I)
760    for (unsigned J = 0, N = I->second.size(); J != N; ++J)
761      (I->first)((I->second)[J]);
762
763  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
764  // because they can contain DenseMaps.
765  for (llvm::DenseMap<const ObjCContainerDecl*,
766       const ASTRecordLayout*>::iterator
767       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
768    // Increment in loop to prevent using deallocated memory.
769    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
770      R->Destroy(*this);
771
772  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
773       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
774    // Increment in loop to prevent using deallocated memory.
775    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
776      R->Destroy(*this);
777  }
778
779  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
780                                                    AEnd = DeclAttrs.end();
781       A != AEnd; ++A)
782    A->second->~AttrVec();
783
784  for (llvm::DenseMap<const DeclContext *, MangleNumberingContext *>::iterator
785           I = MangleNumberingContexts.begin(),
786           E = MangleNumberingContexts.end();
787       I != E; ++I)
788    delete I->second;
789}
790
791void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
792  Deallocations[Callback].push_back(Data);
793}
794
795void
796ASTContext::setExternalSource(OwningPtr<ExternalASTSource> &Source) {
797  ExternalSource.reset(Source.take());
798}
799
800void ASTContext::PrintStats() const {
801  llvm::errs() << "\n*** AST Context Stats:\n";
802  llvm::errs() << "  " << Types.size() << " types total.\n";
803
804  unsigned counts[] = {
805#define TYPE(Name, Parent) 0,
806#define ABSTRACT_TYPE(Name, Parent)
807#include "clang/AST/TypeNodes.def"
808    0 // Extra
809  };
810
811  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
812    Type *T = Types[i];
813    counts[(unsigned)T->getTypeClass()]++;
814  }
815
816  unsigned Idx = 0;
817  unsigned TotalBytes = 0;
818#define TYPE(Name, Parent)                                              \
819  if (counts[Idx])                                                      \
820    llvm::errs() << "    " << counts[Idx] << " " << #Name               \
821                 << " types\n";                                         \
822  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
823  ++Idx;
824#define ABSTRACT_TYPE(Name, Parent)
825#include "clang/AST/TypeNodes.def"
826
827  llvm::errs() << "Total bytes = " << TotalBytes << "\n";
828
829  // Implicit special member functions.
830  llvm::errs() << NumImplicitDefaultConstructorsDeclared << "/"
831               << NumImplicitDefaultConstructors
832               << " implicit default constructors created\n";
833  llvm::errs() << NumImplicitCopyConstructorsDeclared << "/"
834               << NumImplicitCopyConstructors
835               << " implicit copy constructors created\n";
836  if (getLangOpts().CPlusPlus)
837    llvm::errs() << NumImplicitMoveConstructorsDeclared << "/"
838                 << NumImplicitMoveConstructors
839                 << " implicit move constructors created\n";
840  llvm::errs() << NumImplicitCopyAssignmentOperatorsDeclared << "/"
841               << NumImplicitCopyAssignmentOperators
842               << " implicit copy assignment operators created\n";
843  if (getLangOpts().CPlusPlus)
844    llvm::errs() << NumImplicitMoveAssignmentOperatorsDeclared << "/"
845                 << NumImplicitMoveAssignmentOperators
846                 << " implicit move assignment operators created\n";
847  llvm::errs() << NumImplicitDestructorsDeclared << "/"
848               << NumImplicitDestructors
849               << " implicit destructors created\n";
850
851  if (ExternalSource.get()) {
852    llvm::errs() << "\n";
853    ExternalSource->PrintStats();
854  }
855
856  BumpAlloc.PrintStats();
857}
858
859TypedefDecl *ASTContext::getInt128Decl() const {
860  if (!Int128Decl) {
861    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(Int128Ty);
862    Int128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
863                                     getTranslationUnitDecl(),
864                                     SourceLocation(),
865                                     SourceLocation(),
866                                     &Idents.get("__int128_t"),
867                                     TInfo);
868  }
869
870  return Int128Decl;
871}
872
873TypedefDecl *ASTContext::getUInt128Decl() const {
874  if (!UInt128Decl) {
875    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(UnsignedInt128Ty);
876    UInt128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
877                                     getTranslationUnitDecl(),
878                                     SourceLocation(),
879                                     SourceLocation(),
880                                     &Idents.get("__uint128_t"),
881                                     TInfo);
882  }
883
884  return UInt128Decl;
885}
886
887TypeDecl *ASTContext::getFloat128StubType() const {
888  assert(LangOpts.CPlusPlus && "should only be called for c++");
889  if (!Float128StubDecl) {
890    Float128StubDecl = CXXRecordDecl::Create(const_cast<ASTContext &>(*this),
891                                             TTK_Struct,
892                                             getTranslationUnitDecl(),
893                                             SourceLocation(),
894                                             SourceLocation(),
895                                             &Idents.get("__float128"));
896  }
897
898  return Float128StubDecl;
899}
900
901void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
902  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
903  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
904  Types.push_back(Ty);
905}
906
907void ASTContext::InitBuiltinTypes(const TargetInfo &Target) {
908  assert((!this->Target || this->Target == &Target) &&
909         "Incorrect target reinitialization");
910  assert(VoidTy.isNull() && "Context reinitialized?");
911
912  this->Target = &Target;
913
914  ABI.reset(createCXXABI(Target));
915  AddrSpaceMap = getAddressSpaceMap(Target, LangOpts);
916  AddrSpaceMapMangling = isAddrSpaceMapManglingEnabled(Target, LangOpts);
917
918  // C99 6.2.5p19.
919  InitBuiltinType(VoidTy,              BuiltinType::Void);
920
921  // C99 6.2.5p2.
922  InitBuiltinType(BoolTy,              BuiltinType::Bool);
923  // C99 6.2.5p3.
924  if (LangOpts.CharIsSigned)
925    InitBuiltinType(CharTy,            BuiltinType::Char_S);
926  else
927    InitBuiltinType(CharTy,            BuiltinType::Char_U);
928  // C99 6.2.5p4.
929  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
930  InitBuiltinType(ShortTy,             BuiltinType::Short);
931  InitBuiltinType(IntTy,               BuiltinType::Int);
932  InitBuiltinType(LongTy,              BuiltinType::Long);
933  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
934
935  // C99 6.2.5p6.
936  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
937  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
938  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
939  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
940  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
941
942  // C99 6.2.5p10.
943  InitBuiltinType(FloatTy,             BuiltinType::Float);
944  InitBuiltinType(DoubleTy,            BuiltinType::Double);
945  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
946
947  // GNU extension, 128-bit integers.
948  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
949  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
950
951  // C++ 3.9.1p5
952  if (TargetInfo::isTypeSigned(Target.getWCharType()))
953    InitBuiltinType(WCharTy,           BuiltinType::WChar_S);
954  else  // -fshort-wchar makes wchar_t be unsigned.
955    InitBuiltinType(WCharTy,           BuiltinType::WChar_U);
956  if (LangOpts.CPlusPlus && LangOpts.WChar)
957    WideCharTy = WCharTy;
958  else {
959    // C99 (or C++ using -fno-wchar).
960    WideCharTy = getFromTargetType(Target.getWCharType());
961  }
962
963  WIntTy = getFromTargetType(Target.getWIntType());
964
965  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
966    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
967  else // C99
968    Char16Ty = getFromTargetType(Target.getChar16Type());
969
970  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
971    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
972  else // C99
973    Char32Ty = getFromTargetType(Target.getChar32Type());
974
975  // Placeholder type for type-dependent expressions whose type is
976  // completely unknown. No code should ever check a type against
977  // DependentTy and users should never see it; however, it is here to
978  // help diagnose failures to properly check for type-dependent
979  // expressions.
980  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
981
982  // Placeholder type for functions.
983  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
984
985  // Placeholder type for bound members.
986  InitBuiltinType(BoundMemberTy,       BuiltinType::BoundMember);
987
988  // Placeholder type for pseudo-objects.
989  InitBuiltinType(PseudoObjectTy,      BuiltinType::PseudoObject);
990
991  // "any" type; useful for debugger-like clients.
992  InitBuiltinType(UnknownAnyTy,        BuiltinType::UnknownAny);
993
994  // Placeholder type for unbridged ARC casts.
995  InitBuiltinType(ARCUnbridgedCastTy,  BuiltinType::ARCUnbridgedCast);
996
997  // Placeholder type for builtin functions.
998  InitBuiltinType(BuiltinFnTy,  BuiltinType::BuiltinFn);
999
1000  // C99 6.2.5p11.
1001  FloatComplexTy      = getComplexType(FloatTy);
1002  DoubleComplexTy     = getComplexType(DoubleTy);
1003  LongDoubleComplexTy = getComplexType(LongDoubleTy);
1004
1005  // Builtin types for 'id', 'Class', and 'SEL'.
1006  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
1007  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
1008  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
1009
1010  if (LangOpts.OpenCL) {
1011    InitBuiltinType(OCLImage1dTy, BuiltinType::OCLImage1d);
1012    InitBuiltinType(OCLImage1dArrayTy, BuiltinType::OCLImage1dArray);
1013    InitBuiltinType(OCLImage1dBufferTy, BuiltinType::OCLImage1dBuffer);
1014    InitBuiltinType(OCLImage2dTy, BuiltinType::OCLImage2d);
1015    InitBuiltinType(OCLImage2dArrayTy, BuiltinType::OCLImage2dArray);
1016    InitBuiltinType(OCLImage3dTy, BuiltinType::OCLImage3d);
1017
1018    InitBuiltinType(OCLSamplerTy, BuiltinType::OCLSampler);
1019    InitBuiltinType(OCLEventTy, BuiltinType::OCLEvent);
1020  }
1021
1022  // Builtin type for __objc_yes and __objc_no
1023  ObjCBuiltinBoolTy = (Target.useSignedCharForObjCBool() ?
1024                       SignedCharTy : BoolTy);
1025
1026  ObjCConstantStringType = QualType();
1027
1028  ObjCSuperType = QualType();
1029
1030  // void * type
1031  VoidPtrTy = getPointerType(VoidTy);
1032
1033  // nullptr type (C++0x 2.14.7)
1034  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
1035
1036  // half type (OpenCL 6.1.1.1) / ARM NEON __fp16
1037  InitBuiltinType(HalfTy, BuiltinType::Half);
1038
1039  // Builtin type used to help define __builtin_va_list.
1040  VaListTagTy = QualType();
1041}
1042
1043DiagnosticsEngine &ASTContext::getDiagnostics() const {
1044  return SourceMgr.getDiagnostics();
1045}
1046
1047AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
1048  AttrVec *&Result = DeclAttrs[D];
1049  if (!Result) {
1050    void *Mem = Allocate(sizeof(AttrVec));
1051    Result = new (Mem) AttrVec;
1052  }
1053
1054  return *Result;
1055}
1056
1057/// \brief Erase the attributes corresponding to the given declaration.
1058void ASTContext::eraseDeclAttrs(const Decl *D) {
1059  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
1060  if (Pos != DeclAttrs.end()) {
1061    Pos->second->~AttrVec();
1062    DeclAttrs.erase(Pos);
1063  }
1064}
1065
1066// FIXME: Remove ?
1067MemberSpecializationInfo *
1068ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
1069  assert(Var->isStaticDataMember() && "Not a static data member");
1070  return getTemplateOrSpecializationInfo(Var)
1071      .dyn_cast<MemberSpecializationInfo *>();
1072}
1073
1074ASTContext::TemplateOrSpecializationInfo
1075ASTContext::getTemplateOrSpecializationInfo(const VarDecl *Var) {
1076  llvm::DenseMap<const VarDecl *, TemplateOrSpecializationInfo>::iterator Pos =
1077      TemplateOrInstantiation.find(Var);
1078  if (Pos == TemplateOrInstantiation.end())
1079    return TemplateOrSpecializationInfo();
1080
1081  return Pos->second;
1082}
1083
1084void
1085ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
1086                                                TemplateSpecializationKind TSK,
1087                                          SourceLocation PointOfInstantiation) {
1088  assert(Inst->isStaticDataMember() && "Not a static data member");
1089  assert(Tmpl->isStaticDataMember() && "Not a static data member");
1090  setTemplateOrSpecializationInfo(Inst, new (*this) MemberSpecializationInfo(
1091                                            Tmpl, TSK, PointOfInstantiation));
1092}
1093
1094void
1095ASTContext::setTemplateOrSpecializationInfo(VarDecl *Inst,
1096                                            TemplateOrSpecializationInfo TSI) {
1097  assert(!TemplateOrInstantiation[Inst] &&
1098         "Already noted what the variable was instantiated from");
1099  TemplateOrInstantiation[Inst] = TSI;
1100}
1101
1102FunctionDecl *ASTContext::getClassScopeSpecializationPattern(
1103                                                     const FunctionDecl *FD){
1104  assert(FD && "Specialization is 0");
1105  llvm::DenseMap<const FunctionDecl*, FunctionDecl *>::const_iterator Pos
1106    = ClassScopeSpecializationPattern.find(FD);
1107  if (Pos == ClassScopeSpecializationPattern.end())
1108    return 0;
1109
1110  return Pos->second;
1111}
1112
1113void ASTContext::setClassScopeSpecializationPattern(FunctionDecl *FD,
1114                                        FunctionDecl *Pattern) {
1115  assert(FD && "Specialization is 0");
1116  assert(Pattern && "Class scope specialization pattern is 0");
1117  ClassScopeSpecializationPattern[FD] = Pattern;
1118}
1119
1120NamedDecl *
1121ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
1122  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
1123    = InstantiatedFromUsingDecl.find(UUD);
1124  if (Pos == InstantiatedFromUsingDecl.end())
1125    return 0;
1126
1127  return Pos->second;
1128}
1129
1130void
1131ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
1132  assert((isa<UsingDecl>(Pattern) ||
1133          isa<UnresolvedUsingValueDecl>(Pattern) ||
1134          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
1135         "pattern decl is not a using decl");
1136  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
1137  InstantiatedFromUsingDecl[Inst] = Pattern;
1138}
1139
1140UsingShadowDecl *
1141ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
1142  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
1143    = InstantiatedFromUsingShadowDecl.find(Inst);
1144  if (Pos == InstantiatedFromUsingShadowDecl.end())
1145    return 0;
1146
1147  return Pos->second;
1148}
1149
1150void
1151ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
1152                                               UsingShadowDecl *Pattern) {
1153  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
1154  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
1155}
1156
1157FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
1158  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
1159    = InstantiatedFromUnnamedFieldDecl.find(Field);
1160  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
1161    return 0;
1162
1163  return Pos->second;
1164}
1165
1166void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
1167                                                     FieldDecl *Tmpl) {
1168  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
1169  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
1170  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
1171         "Already noted what unnamed field was instantiated from");
1172
1173  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
1174}
1175
1176ASTContext::overridden_cxx_method_iterator
1177ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
1178  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1179    = OverriddenMethods.find(Method->getCanonicalDecl());
1180  if (Pos == OverriddenMethods.end())
1181    return 0;
1182
1183  return Pos->second.begin();
1184}
1185
1186ASTContext::overridden_cxx_method_iterator
1187ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
1188  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1189    = OverriddenMethods.find(Method->getCanonicalDecl());
1190  if (Pos == OverriddenMethods.end())
1191    return 0;
1192
1193  return Pos->second.end();
1194}
1195
1196unsigned
1197ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
1198  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1199    = OverriddenMethods.find(Method->getCanonicalDecl());
1200  if (Pos == OverriddenMethods.end())
1201    return 0;
1202
1203  return Pos->second.size();
1204}
1205
1206void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
1207                                     const CXXMethodDecl *Overridden) {
1208  assert(Method->isCanonicalDecl() && Overridden->isCanonicalDecl());
1209  OverriddenMethods[Method].push_back(Overridden);
1210}
1211
1212void ASTContext::getOverriddenMethods(
1213                      const NamedDecl *D,
1214                      SmallVectorImpl<const NamedDecl *> &Overridden) const {
1215  assert(D);
1216
1217  if (const CXXMethodDecl *CXXMethod = dyn_cast<CXXMethodDecl>(D)) {
1218    Overridden.append(overridden_methods_begin(CXXMethod),
1219                      overridden_methods_end(CXXMethod));
1220    return;
1221  }
1222
1223  const ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(D);
1224  if (!Method)
1225    return;
1226
1227  SmallVector<const ObjCMethodDecl *, 8> OverDecls;
1228  Method->getOverriddenMethods(OverDecls);
1229  Overridden.append(OverDecls.begin(), OverDecls.end());
1230}
1231
1232void ASTContext::addedLocalImportDecl(ImportDecl *Import) {
1233  assert(!Import->NextLocalImport && "Import declaration already in the chain");
1234  assert(!Import->isFromASTFile() && "Non-local import declaration");
1235  if (!FirstLocalImport) {
1236    FirstLocalImport = Import;
1237    LastLocalImport = Import;
1238    return;
1239  }
1240
1241  LastLocalImport->NextLocalImport = Import;
1242  LastLocalImport = Import;
1243}
1244
1245//===----------------------------------------------------------------------===//
1246//                         Type Sizing and Analysis
1247//===----------------------------------------------------------------------===//
1248
1249/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
1250/// scalar floating point type.
1251const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
1252  const BuiltinType *BT = T->getAs<BuiltinType>();
1253  assert(BT && "Not a floating point type!");
1254  switch (BT->getKind()) {
1255  default: llvm_unreachable("Not a floating point type!");
1256  case BuiltinType::Half:       return Target->getHalfFormat();
1257  case BuiltinType::Float:      return Target->getFloatFormat();
1258  case BuiltinType::Double:     return Target->getDoubleFormat();
1259  case BuiltinType::LongDouble: return Target->getLongDoubleFormat();
1260  }
1261}
1262
1263CharUnits ASTContext::getDeclAlign(const Decl *D, bool ForAlignof) const {
1264  unsigned Align = Target->getCharWidth();
1265
1266  bool UseAlignAttrOnly = false;
1267  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
1268    Align = AlignFromAttr;
1269
1270    // __attribute__((aligned)) can increase or decrease alignment
1271    // *except* on a struct or struct member, where it only increases
1272    // alignment unless 'packed' is also specified.
1273    //
1274    // It is an error for alignas to decrease alignment, so we can
1275    // ignore that possibility;  Sema should diagnose it.
1276    if (isa<FieldDecl>(D)) {
1277      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
1278        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1279    } else {
1280      UseAlignAttrOnly = true;
1281    }
1282  }
1283  else if (isa<FieldDecl>(D))
1284      UseAlignAttrOnly =
1285        D->hasAttr<PackedAttr>() ||
1286        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1287
1288  // If we're using the align attribute only, just ignore everything
1289  // else about the declaration and its type.
1290  if (UseAlignAttrOnly) {
1291    // do nothing
1292
1293  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
1294    QualType T = VD->getType();
1295    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
1296      if (ForAlignof)
1297        T = RT->getPointeeType();
1298      else
1299        T = getPointerType(RT->getPointeeType());
1300    }
1301    if (!T->isIncompleteType() && !T->isFunctionType()) {
1302      // Adjust alignments of declarations with array type by the
1303      // large-array alignment on the target.
1304      if (const ArrayType *arrayType = getAsArrayType(T)) {
1305        unsigned MinWidth = Target->getLargeArrayMinWidth();
1306        if (!ForAlignof && MinWidth) {
1307          if (isa<VariableArrayType>(arrayType))
1308            Align = std::max(Align, Target->getLargeArrayAlign());
1309          else if (isa<ConstantArrayType>(arrayType) &&
1310                   MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
1311            Align = std::max(Align, Target->getLargeArrayAlign());
1312        }
1313
1314        // Walk through any array types while we're at it.
1315        T = getBaseElementType(arrayType);
1316      }
1317      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
1318      if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1319        if (VD->hasGlobalStorage())
1320          Align = std::max(Align, getTargetInfo().getMinGlobalAlign());
1321      }
1322    }
1323
1324    // Fields can be subject to extra alignment constraints, like if
1325    // the field is packed, the struct is packed, or the struct has a
1326    // a max-field-alignment constraint (#pragma pack).  So calculate
1327    // the actual alignment of the field within the struct, and then
1328    // (as we're expected to) constrain that by the alignment of the type.
1329    if (const FieldDecl *Field = dyn_cast<FieldDecl>(VD)) {
1330      const RecordDecl *Parent = Field->getParent();
1331      // We can only produce a sensible answer if the record is valid.
1332      if (!Parent->isInvalidDecl()) {
1333        const ASTRecordLayout &Layout = getASTRecordLayout(Parent);
1334
1335        // Start with the record's overall alignment.
1336        unsigned FieldAlign = toBits(Layout.getAlignment());
1337
1338        // Use the GCD of that and the offset within the record.
1339        uint64_t Offset = Layout.getFieldOffset(Field->getFieldIndex());
1340        if (Offset > 0) {
1341          // Alignment is always a power of 2, so the GCD will be a power of 2,
1342          // which means we get to do this crazy thing instead of Euclid's.
1343          uint64_t LowBitOfOffset = Offset & (~Offset + 1);
1344          if (LowBitOfOffset < FieldAlign)
1345            FieldAlign = static_cast<unsigned>(LowBitOfOffset);
1346        }
1347
1348        Align = std::min(Align, FieldAlign);
1349      }
1350    }
1351  }
1352
1353  return toCharUnitsFromBits(Align);
1354}
1355
1356// getTypeInfoDataSizeInChars - Return the size of a type, in
1357// chars. If the type is a record, its data size is returned.  This is
1358// the size of the memcpy that's performed when assigning this type
1359// using a trivial copy/move assignment operator.
1360std::pair<CharUnits, CharUnits>
1361ASTContext::getTypeInfoDataSizeInChars(QualType T) const {
1362  std::pair<CharUnits, CharUnits> sizeAndAlign = getTypeInfoInChars(T);
1363
1364  // In C++, objects can sometimes be allocated into the tail padding
1365  // of a base-class subobject.  We decide whether that's possible
1366  // during class layout, so here we can just trust the layout results.
1367  if (getLangOpts().CPlusPlus) {
1368    if (const RecordType *RT = T->getAs<RecordType>()) {
1369      const ASTRecordLayout &layout = getASTRecordLayout(RT->getDecl());
1370      sizeAndAlign.first = layout.getDataSize();
1371    }
1372  }
1373
1374  return sizeAndAlign;
1375}
1376
1377/// getConstantArrayInfoInChars - Performing the computation in CharUnits
1378/// instead of in bits prevents overflowing the uint64_t for some large arrays.
1379std::pair<CharUnits, CharUnits>
1380static getConstantArrayInfoInChars(const ASTContext &Context,
1381                                   const ConstantArrayType *CAT) {
1382  std::pair<CharUnits, CharUnits> EltInfo =
1383      Context.getTypeInfoInChars(CAT->getElementType());
1384  uint64_t Size = CAT->getSize().getZExtValue();
1385  assert((Size == 0 || static_cast<uint64_t>(EltInfo.first.getQuantity()) <=
1386              (uint64_t)(-1)/Size) &&
1387         "Overflow in array type char size evaluation");
1388  uint64_t Width = EltInfo.first.getQuantity() * Size;
1389  unsigned Align = EltInfo.second.getQuantity();
1390  Width = llvm::RoundUpToAlignment(Width, Align);
1391  return std::make_pair(CharUnits::fromQuantity(Width),
1392                        CharUnits::fromQuantity(Align));
1393}
1394
1395std::pair<CharUnits, CharUnits>
1396ASTContext::getTypeInfoInChars(const Type *T) const {
1397  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(T))
1398    return getConstantArrayInfoInChars(*this, CAT);
1399  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
1400  return std::make_pair(toCharUnitsFromBits(Info.first),
1401                        toCharUnitsFromBits(Info.second));
1402}
1403
1404std::pair<CharUnits, CharUnits>
1405ASTContext::getTypeInfoInChars(QualType T) const {
1406  return getTypeInfoInChars(T.getTypePtr());
1407}
1408
1409std::pair<uint64_t, unsigned> ASTContext::getTypeInfo(const Type *T) const {
1410  TypeInfoMap::iterator it = MemoizedTypeInfo.find(T);
1411  if (it != MemoizedTypeInfo.end())
1412    return it->second;
1413
1414  std::pair<uint64_t, unsigned> Info = getTypeInfoImpl(T);
1415  MemoizedTypeInfo.insert(std::make_pair(T, Info));
1416  return Info;
1417}
1418
1419/// getTypeInfoImpl - Return the size of the specified type, in bits.  This
1420/// method does not work on incomplete types.
1421///
1422/// FIXME: Pointers into different addr spaces could have different sizes and
1423/// alignment requirements: getPointerInfo should take an AddrSpace, this
1424/// should take a QualType, &c.
1425std::pair<uint64_t, unsigned>
1426ASTContext::getTypeInfoImpl(const Type *T) const {
1427  uint64_t Width=0;
1428  unsigned Align=8;
1429  switch (T->getTypeClass()) {
1430#define TYPE(Class, Base)
1431#define ABSTRACT_TYPE(Class, Base)
1432#define NON_CANONICAL_TYPE(Class, Base)
1433#define DEPENDENT_TYPE(Class, Base) case Type::Class:
1434#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base)                       \
1435  case Type::Class:                                                            \
1436  assert(!T->isDependentType() && "should not see dependent types here");      \
1437  return getTypeInfo(cast<Class##Type>(T)->desugar().getTypePtr());
1438#include "clang/AST/TypeNodes.def"
1439    llvm_unreachable("Should not see dependent types");
1440
1441  case Type::FunctionNoProto:
1442  case Type::FunctionProto:
1443    // GCC extension: alignof(function) = 32 bits
1444    Width = 0;
1445    Align = 32;
1446    break;
1447
1448  case Type::IncompleteArray:
1449  case Type::VariableArray:
1450    Width = 0;
1451    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
1452    break;
1453
1454  case Type::ConstantArray: {
1455    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
1456
1457    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
1458    uint64_t Size = CAT->getSize().getZExtValue();
1459    assert((Size == 0 || EltInfo.first <= (uint64_t)(-1)/Size) &&
1460           "Overflow in array type bit size evaluation");
1461    Width = EltInfo.first*Size;
1462    Align = EltInfo.second;
1463    Width = llvm::RoundUpToAlignment(Width, Align);
1464    break;
1465  }
1466  case Type::ExtVector:
1467  case Type::Vector: {
1468    const VectorType *VT = cast<VectorType>(T);
1469    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
1470    Width = EltInfo.first*VT->getNumElements();
1471    Align = Width;
1472    // If the alignment is not a power of 2, round up to the next power of 2.
1473    // This happens for non-power-of-2 length vectors.
1474    if (Align & (Align-1)) {
1475      Align = llvm::NextPowerOf2(Align);
1476      Width = llvm::RoundUpToAlignment(Width, Align);
1477    }
1478    // Adjust the alignment based on the target max.
1479    uint64_t TargetVectorAlign = Target->getMaxVectorAlign();
1480    if (TargetVectorAlign && TargetVectorAlign < Align)
1481      Align = TargetVectorAlign;
1482    break;
1483  }
1484
1485  case Type::Builtin:
1486    switch (cast<BuiltinType>(T)->getKind()) {
1487    default: llvm_unreachable("Unknown builtin type!");
1488    case BuiltinType::Void:
1489      // GCC extension: alignof(void) = 8 bits.
1490      Width = 0;
1491      Align = 8;
1492      break;
1493
1494    case BuiltinType::Bool:
1495      Width = Target->getBoolWidth();
1496      Align = Target->getBoolAlign();
1497      break;
1498    case BuiltinType::Char_S:
1499    case BuiltinType::Char_U:
1500    case BuiltinType::UChar:
1501    case BuiltinType::SChar:
1502      Width = Target->getCharWidth();
1503      Align = Target->getCharAlign();
1504      break;
1505    case BuiltinType::WChar_S:
1506    case BuiltinType::WChar_U:
1507      Width = Target->getWCharWidth();
1508      Align = Target->getWCharAlign();
1509      break;
1510    case BuiltinType::Char16:
1511      Width = Target->getChar16Width();
1512      Align = Target->getChar16Align();
1513      break;
1514    case BuiltinType::Char32:
1515      Width = Target->getChar32Width();
1516      Align = Target->getChar32Align();
1517      break;
1518    case BuiltinType::UShort:
1519    case BuiltinType::Short:
1520      Width = Target->getShortWidth();
1521      Align = Target->getShortAlign();
1522      break;
1523    case BuiltinType::UInt:
1524    case BuiltinType::Int:
1525      Width = Target->getIntWidth();
1526      Align = Target->getIntAlign();
1527      break;
1528    case BuiltinType::ULong:
1529    case BuiltinType::Long:
1530      Width = Target->getLongWidth();
1531      Align = Target->getLongAlign();
1532      break;
1533    case BuiltinType::ULongLong:
1534    case BuiltinType::LongLong:
1535      Width = Target->getLongLongWidth();
1536      Align = Target->getLongLongAlign();
1537      break;
1538    case BuiltinType::Int128:
1539    case BuiltinType::UInt128:
1540      Width = 128;
1541      Align = 128; // int128_t is 128-bit aligned on all targets.
1542      break;
1543    case BuiltinType::Half:
1544      Width = Target->getHalfWidth();
1545      Align = Target->getHalfAlign();
1546      break;
1547    case BuiltinType::Float:
1548      Width = Target->getFloatWidth();
1549      Align = Target->getFloatAlign();
1550      break;
1551    case BuiltinType::Double:
1552      Width = Target->getDoubleWidth();
1553      Align = Target->getDoubleAlign();
1554      break;
1555    case BuiltinType::LongDouble:
1556      Width = Target->getLongDoubleWidth();
1557      Align = Target->getLongDoubleAlign();
1558      break;
1559    case BuiltinType::NullPtr:
1560      Width = Target->getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
1561      Align = Target->getPointerAlign(0); //   == sizeof(void*)
1562      break;
1563    case BuiltinType::ObjCId:
1564    case BuiltinType::ObjCClass:
1565    case BuiltinType::ObjCSel:
1566      Width = Target->getPointerWidth(0);
1567      Align = Target->getPointerAlign(0);
1568      break;
1569    case BuiltinType::OCLSampler:
1570      // Samplers are modeled as integers.
1571      Width = Target->getIntWidth();
1572      Align = Target->getIntAlign();
1573      break;
1574    case BuiltinType::OCLEvent:
1575    case BuiltinType::OCLImage1d:
1576    case BuiltinType::OCLImage1dArray:
1577    case BuiltinType::OCLImage1dBuffer:
1578    case BuiltinType::OCLImage2d:
1579    case BuiltinType::OCLImage2dArray:
1580    case BuiltinType::OCLImage3d:
1581      // Currently these types are pointers to opaque types.
1582      Width = Target->getPointerWidth(0);
1583      Align = Target->getPointerAlign(0);
1584      break;
1585    }
1586    break;
1587  case Type::ObjCObjectPointer:
1588    Width = Target->getPointerWidth(0);
1589    Align = Target->getPointerAlign(0);
1590    break;
1591  case Type::BlockPointer: {
1592    unsigned AS = getTargetAddressSpace(
1593        cast<BlockPointerType>(T)->getPointeeType());
1594    Width = Target->getPointerWidth(AS);
1595    Align = Target->getPointerAlign(AS);
1596    break;
1597  }
1598  case Type::LValueReference:
1599  case Type::RValueReference: {
1600    // alignof and sizeof should never enter this code path here, so we go
1601    // the pointer route.
1602    unsigned AS = getTargetAddressSpace(
1603        cast<ReferenceType>(T)->getPointeeType());
1604    Width = Target->getPointerWidth(AS);
1605    Align = Target->getPointerAlign(AS);
1606    break;
1607  }
1608  case Type::Pointer: {
1609    unsigned AS = getTargetAddressSpace(cast<PointerType>(T)->getPointeeType());
1610    Width = Target->getPointerWidth(AS);
1611    Align = Target->getPointerAlign(AS);
1612    break;
1613  }
1614  case Type::MemberPointer: {
1615    const MemberPointerType *MPT = cast<MemberPointerType>(T);
1616    llvm::tie(Width, Align) = ABI->getMemberPointerWidthAndAlign(MPT);
1617    break;
1618  }
1619  case Type::Complex: {
1620    // Complex types have the same alignment as their elements, but twice the
1621    // size.
1622    std::pair<uint64_t, unsigned> EltInfo =
1623      getTypeInfo(cast<ComplexType>(T)->getElementType());
1624    Width = EltInfo.first*2;
1625    Align = EltInfo.second;
1626    break;
1627  }
1628  case Type::ObjCObject:
1629    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
1630  case Type::Decayed:
1631    return getTypeInfo(cast<DecayedType>(T)->getDecayedType().getTypePtr());
1632  case Type::ObjCInterface: {
1633    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
1634    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
1635    Width = toBits(Layout.getSize());
1636    Align = toBits(Layout.getAlignment());
1637    break;
1638  }
1639  case Type::Record:
1640  case Type::Enum: {
1641    const TagType *TT = cast<TagType>(T);
1642
1643    if (TT->getDecl()->isInvalidDecl()) {
1644      Width = 8;
1645      Align = 8;
1646      break;
1647    }
1648
1649    if (const EnumType *ET = dyn_cast<EnumType>(TT))
1650      return getTypeInfo(ET->getDecl()->getIntegerType());
1651
1652    const RecordType *RT = cast<RecordType>(TT);
1653    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
1654    Width = toBits(Layout.getSize());
1655    Align = toBits(Layout.getAlignment());
1656    break;
1657  }
1658
1659  case Type::SubstTemplateTypeParm:
1660    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
1661                       getReplacementType().getTypePtr());
1662
1663  case Type::Auto: {
1664    const AutoType *A = cast<AutoType>(T);
1665    assert(!A->getDeducedType().isNull() &&
1666           "cannot request the size of an undeduced or dependent auto type");
1667    return getTypeInfo(A->getDeducedType().getTypePtr());
1668  }
1669
1670  case Type::Paren:
1671    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
1672
1673  case Type::Typedef: {
1674    const TypedefNameDecl *Typedef = cast<TypedefType>(T)->getDecl();
1675    std::pair<uint64_t, unsigned> Info
1676      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
1677    // If the typedef has an aligned attribute on it, it overrides any computed
1678    // alignment we have.  This violates the GCC documentation (which says that
1679    // attribute(aligned) can only round up) but matches its implementation.
1680    if (unsigned AttrAlign = Typedef->getMaxAlignment())
1681      Align = AttrAlign;
1682    else
1683      Align = Info.second;
1684    Width = Info.first;
1685    break;
1686  }
1687
1688  case Type::Elaborated:
1689    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
1690
1691  case Type::Attributed:
1692    return getTypeInfo(
1693                  cast<AttributedType>(T)->getEquivalentType().getTypePtr());
1694
1695  case Type::Atomic: {
1696    // Start with the base type information.
1697    std::pair<uint64_t, unsigned> Info
1698      = getTypeInfo(cast<AtomicType>(T)->getValueType());
1699    Width = Info.first;
1700    Align = Info.second;
1701
1702    // If the size of the type doesn't exceed the platform's max
1703    // atomic promotion width, make the size and alignment more
1704    // favorable to atomic operations:
1705    if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth()) {
1706      // Round the size up to a power of 2.
1707      if (!llvm::isPowerOf2_64(Width))
1708        Width = llvm::NextPowerOf2(Width);
1709
1710      // Set the alignment equal to the size.
1711      Align = static_cast<unsigned>(Width);
1712    }
1713  }
1714
1715  }
1716
1717  assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
1718  return std::make_pair(Width, Align);
1719}
1720
1721/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1722CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1723  return CharUnits::fromQuantity(BitSize / getCharWidth());
1724}
1725
1726/// toBits - Convert a size in characters to a size in characters.
1727int64_t ASTContext::toBits(CharUnits CharSize) const {
1728  return CharSize.getQuantity() * getCharWidth();
1729}
1730
1731/// getTypeSizeInChars - Return the size of the specified type, in characters.
1732/// This method does not work on incomplete types.
1733CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1734  return getTypeInfoInChars(T).first;
1735}
1736CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1737  return getTypeInfoInChars(T).first;
1738}
1739
1740/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1741/// characters. This method does not work on incomplete types.
1742CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1743  return toCharUnitsFromBits(getTypeAlign(T));
1744}
1745CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1746  return toCharUnitsFromBits(getTypeAlign(T));
1747}
1748
1749/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1750/// type for the current target in bits.  This can be different than the ABI
1751/// alignment in cases where it is beneficial for performance to overalign
1752/// a data type.
1753unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1754  unsigned ABIAlign = getTypeAlign(T);
1755
1756  // Double and long long should be naturally aligned if possible.
1757  if (const ComplexType* CT = T->getAs<ComplexType>())
1758    T = CT->getElementType().getTypePtr();
1759  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1760      T->isSpecificBuiltinType(BuiltinType::LongLong) ||
1761      T->isSpecificBuiltinType(BuiltinType::ULongLong))
1762    return std::max(ABIAlign, (unsigned)getTypeSize(T));
1763
1764  return ABIAlign;
1765}
1766
1767/// getAlignOfGlobalVar - Return the alignment in bits that should be given
1768/// to a global variable of the specified type.
1769unsigned ASTContext::getAlignOfGlobalVar(QualType T) const {
1770  return std::max(getTypeAlign(T), getTargetInfo().getMinGlobalAlign());
1771}
1772
1773/// getAlignOfGlobalVarInChars - Return the alignment in characters that
1774/// should be given to a global variable of the specified type.
1775CharUnits ASTContext::getAlignOfGlobalVarInChars(QualType T) const {
1776  return toCharUnitsFromBits(getAlignOfGlobalVar(T));
1777}
1778
1779/// DeepCollectObjCIvars -
1780/// This routine first collects all declared, but not synthesized, ivars in
1781/// super class and then collects all ivars, including those synthesized for
1782/// current class. This routine is used for implementation of current class
1783/// when all ivars, declared and synthesized are known.
1784///
1785void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1786                                      bool leafClass,
1787                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1788  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1789    DeepCollectObjCIvars(SuperClass, false, Ivars);
1790  if (!leafClass) {
1791    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
1792         E = OI->ivar_end(); I != E; ++I)
1793      Ivars.push_back(*I);
1794  } else {
1795    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1796    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1797         Iv= Iv->getNextIvar())
1798      Ivars.push_back(Iv);
1799  }
1800}
1801
1802/// CollectInheritedProtocols - Collect all protocols in current class and
1803/// those inherited by it.
1804void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1805                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1806  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1807    // We can use protocol_iterator here instead of
1808    // all_referenced_protocol_iterator since we are walking all categories.
1809    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
1810         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
1811      ObjCProtocolDecl *Proto = (*P);
1812      Protocols.insert(Proto->getCanonicalDecl());
1813      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1814           PE = Proto->protocol_end(); P != PE; ++P) {
1815        Protocols.insert((*P)->getCanonicalDecl());
1816        CollectInheritedProtocols(*P, Protocols);
1817      }
1818    }
1819
1820    // Categories of this Interface.
1821    for (ObjCInterfaceDecl::visible_categories_iterator
1822           Cat = OI->visible_categories_begin(),
1823           CatEnd = OI->visible_categories_end();
1824         Cat != CatEnd; ++Cat) {
1825      CollectInheritedProtocols(*Cat, Protocols);
1826    }
1827
1828    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1829      while (SD) {
1830        CollectInheritedProtocols(SD, Protocols);
1831        SD = SD->getSuperClass();
1832      }
1833  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1834    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
1835         PE = OC->protocol_end(); P != PE; ++P) {
1836      ObjCProtocolDecl *Proto = (*P);
1837      Protocols.insert(Proto->getCanonicalDecl());
1838      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1839           PE = Proto->protocol_end(); P != PE; ++P)
1840        CollectInheritedProtocols(*P, Protocols);
1841    }
1842  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
1843    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
1844         PE = OP->protocol_end(); P != PE; ++P) {
1845      ObjCProtocolDecl *Proto = (*P);
1846      Protocols.insert(Proto->getCanonicalDecl());
1847      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1848           PE = Proto->protocol_end(); P != PE; ++P)
1849        CollectInheritedProtocols(*P, Protocols);
1850    }
1851  }
1852}
1853
1854unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
1855  unsigned count = 0;
1856  // Count ivars declared in class extension.
1857  for (ObjCInterfaceDecl::known_extensions_iterator
1858         Ext = OI->known_extensions_begin(),
1859         ExtEnd = OI->known_extensions_end();
1860       Ext != ExtEnd; ++Ext) {
1861    count += Ext->ivar_size();
1862  }
1863
1864  // Count ivar defined in this class's implementation.  This
1865  // includes synthesized ivars.
1866  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
1867    count += ImplDecl->ivar_size();
1868
1869  return count;
1870}
1871
1872bool ASTContext::isSentinelNullExpr(const Expr *E) {
1873  if (!E)
1874    return false;
1875
1876  // nullptr_t is always treated as null.
1877  if (E->getType()->isNullPtrType()) return true;
1878
1879  if (E->getType()->isAnyPointerType() &&
1880      E->IgnoreParenCasts()->isNullPointerConstant(*this,
1881                                                Expr::NPC_ValueDependentIsNull))
1882    return true;
1883
1884  // Unfortunately, __null has type 'int'.
1885  if (isa<GNUNullExpr>(E)) return true;
1886
1887  return false;
1888}
1889
1890/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
1891ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
1892  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1893    I = ObjCImpls.find(D);
1894  if (I != ObjCImpls.end())
1895    return cast<ObjCImplementationDecl>(I->second);
1896  return 0;
1897}
1898/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
1899ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
1900  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1901    I = ObjCImpls.find(D);
1902  if (I != ObjCImpls.end())
1903    return cast<ObjCCategoryImplDecl>(I->second);
1904  return 0;
1905}
1906
1907/// \brief Set the implementation of ObjCInterfaceDecl.
1908void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1909                           ObjCImplementationDecl *ImplD) {
1910  assert(IFaceD && ImplD && "Passed null params");
1911  ObjCImpls[IFaceD] = ImplD;
1912}
1913/// \brief Set the implementation of ObjCCategoryDecl.
1914void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1915                           ObjCCategoryImplDecl *ImplD) {
1916  assert(CatD && ImplD && "Passed null params");
1917  ObjCImpls[CatD] = ImplD;
1918}
1919
1920const ObjCInterfaceDecl *ASTContext::getObjContainingInterface(
1921                                              const NamedDecl *ND) const {
1922  if (const ObjCInterfaceDecl *ID =
1923          dyn_cast<ObjCInterfaceDecl>(ND->getDeclContext()))
1924    return ID;
1925  if (const ObjCCategoryDecl *CD =
1926          dyn_cast<ObjCCategoryDecl>(ND->getDeclContext()))
1927    return CD->getClassInterface();
1928  if (const ObjCImplDecl *IMD =
1929          dyn_cast<ObjCImplDecl>(ND->getDeclContext()))
1930    return IMD->getClassInterface();
1931
1932  return 0;
1933}
1934
1935/// \brief Get the copy initialization expression of VarDecl,or NULL if
1936/// none exists.
1937Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
1938  assert(VD && "Passed null params");
1939  assert(VD->hasAttr<BlocksAttr>() &&
1940         "getBlockVarCopyInits - not __block var");
1941  llvm::DenseMap<const VarDecl*, Expr*>::iterator
1942    I = BlockVarCopyInits.find(VD);
1943  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : 0;
1944}
1945
1946/// \brief Set the copy inialization expression of a block var decl.
1947void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
1948  assert(VD && Init && "Passed null params");
1949  assert(VD->hasAttr<BlocksAttr>() &&
1950         "setBlockVarCopyInits - not __block var");
1951  BlockVarCopyInits[VD] = Init;
1952}
1953
1954TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1955                                                 unsigned DataSize) const {
1956  if (!DataSize)
1957    DataSize = TypeLoc::getFullDataSizeForType(T);
1958  else
1959    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1960           "incorrect data size provided to CreateTypeSourceInfo!");
1961
1962  TypeSourceInfo *TInfo =
1963    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1964  new (TInfo) TypeSourceInfo(T);
1965  return TInfo;
1966}
1967
1968TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1969                                                     SourceLocation L) const {
1970  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1971  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
1972  return DI;
1973}
1974
1975const ASTRecordLayout &
1976ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
1977  return getObjCLayout(D, 0);
1978}
1979
1980const ASTRecordLayout &
1981ASTContext::getASTObjCImplementationLayout(
1982                                        const ObjCImplementationDecl *D) const {
1983  return getObjCLayout(D->getClassInterface(), D);
1984}
1985
1986//===----------------------------------------------------------------------===//
1987//                   Type creation/memoization methods
1988//===----------------------------------------------------------------------===//
1989
1990QualType
1991ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
1992  unsigned fastQuals = quals.getFastQualifiers();
1993  quals.removeFastQualifiers();
1994
1995  // Check if we've already instantiated this type.
1996  llvm::FoldingSetNodeID ID;
1997  ExtQuals::Profile(ID, baseType, quals);
1998  void *insertPos = 0;
1999  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
2000    assert(eq->getQualifiers() == quals);
2001    return QualType(eq, fastQuals);
2002  }
2003
2004  // If the base type is not canonical, make the appropriate canonical type.
2005  QualType canon;
2006  if (!baseType->isCanonicalUnqualified()) {
2007    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
2008    canonSplit.Quals.addConsistentQualifiers(quals);
2009    canon = getExtQualType(canonSplit.Ty, canonSplit.Quals);
2010
2011    // Re-find the insert position.
2012    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
2013  }
2014
2015  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
2016  ExtQualNodes.InsertNode(eq, insertPos);
2017  return QualType(eq, fastQuals);
2018}
2019
2020QualType
2021ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
2022  QualType CanT = getCanonicalType(T);
2023  if (CanT.getAddressSpace() == AddressSpace)
2024    return T;
2025
2026  // If we are composing extended qualifiers together, merge together
2027  // into one ExtQuals node.
2028  QualifierCollector Quals;
2029  const Type *TypeNode = Quals.strip(T);
2030
2031  // If this type already has an address space specified, it cannot get
2032  // another one.
2033  assert(!Quals.hasAddressSpace() &&
2034         "Type cannot be in multiple addr spaces!");
2035  Quals.addAddressSpace(AddressSpace);
2036
2037  return getExtQualType(TypeNode, Quals);
2038}
2039
2040QualType ASTContext::getObjCGCQualType(QualType T,
2041                                       Qualifiers::GC GCAttr) const {
2042  QualType CanT = getCanonicalType(T);
2043  if (CanT.getObjCGCAttr() == GCAttr)
2044    return T;
2045
2046  if (const PointerType *ptr = T->getAs<PointerType>()) {
2047    QualType Pointee = ptr->getPointeeType();
2048    if (Pointee->isAnyPointerType()) {
2049      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
2050      return getPointerType(ResultType);
2051    }
2052  }
2053
2054  // If we are composing extended qualifiers together, merge together
2055  // into one ExtQuals node.
2056  QualifierCollector Quals;
2057  const Type *TypeNode = Quals.strip(T);
2058
2059  // If this type already has an ObjCGC specified, it cannot get
2060  // another one.
2061  assert(!Quals.hasObjCGCAttr() &&
2062         "Type cannot have multiple ObjCGCs!");
2063  Quals.addObjCGCAttr(GCAttr);
2064
2065  return getExtQualType(TypeNode, Quals);
2066}
2067
2068const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
2069                                                   FunctionType::ExtInfo Info) {
2070  if (T->getExtInfo() == Info)
2071    return T;
2072
2073  QualType Result;
2074  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
2075    Result = getFunctionNoProtoType(FNPT->getResultType(), Info);
2076  } else {
2077    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
2078    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
2079    EPI.ExtInfo = Info;
2080    Result = getFunctionType(FPT->getResultType(), FPT->getArgTypes(), EPI);
2081  }
2082
2083  return cast<FunctionType>(Result.getTypePtr());
2084}
2085
2086void ASTContext::adjustDeducedFunctionResultType(FunctionDecl *FD,
2087                                                 QualType ResultType) {
2088  FD = FD->getMostRecentDecl();
2089  while (true) {
2090    const FunctionProtoType *FPT = FD->getType()->castAs<FunctionProtoType>();
2091    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
2092    FD->setType(getFunctionType(ResultType, FPT->getArgTypes(), EPI));
2093    if (FunctionDecl *Next = FD->getPreviousDecl())
2094      FD = Next;
2095    else
2096      break;
2097  }
2098  if (ASTMutationListener *L = getASTMutationListener())
2099    L->DeducedReturnType(FD, ResultType);
2100}
2101
2102/// getComplexType - Return the uniqued reference to the type for a complex
2103/// number with the specified element type.
2104QualType ASTContext::getComplexType(QualType T) const {
2105  // Unique pointers, to guarantee there is only one pointer of a particular
2106  // structure.
2107  llvm::FoldingSetNodeID ID;
2108  ComplexType::Profile(ID, T);
2109
2110  void *InsertPos = 0;
2111  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
2112    return QualType(CT, 0);
2113
2114  // If the pointee type isn't canonical, this won't be a canonical type either,
2115  // so fill in the canonical type field.
2116  QualType Canonical;
2117  if (!T.isCanonical()) {
2118    Canonical = getComplexType(getCanonicalType(T));
2119
2120    // Get the new insert position for the node we care about.
2121    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
2122    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2123  }
2124  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
2125  Types.push_back(New);
2126  ComplexTypes.InsertNode(New, InsertPos);
2127  return QualType(New, 0);
2128}
2129
2130/// getPointerType - Return the uniqued reference to the type for a pointer to
2131/// the specified type.
2132QualType ASTContext::getPointerType(QualType T) const {
2133  // Unique pointers, to guarantee there is only one pointer of a particular
2134  // structure.
2135  llvm::FoldingSetNodeID ID;
2136  PointerType::Profile(ID, T);
2137
2138  void *InsertPos = 0;
2139  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2140    return QualType(PT, 0);
2141
2142  // If the pointee type isn't canonical, this won't be a canonical type either,
2143  // so fill in the canonical type field.
2144  QualType Canonical;
2145  if (!T.isCanonical()) {
2146    Canonical = getPointerType(getCanonicalType(T));
2147
2148    // Get the new insert position for the node we care about.
2149    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2150    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2151  }
2152  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
2153  Types.push_back(New);
2154  PointerTypes.InsertNode(New, InsertPos);
2155  return QualType(New, 0);
2156}
2157
2158QualType ASTContext::getDecayedType(QualType T) const {
2159  assert((T->isArrayType() || T->isFunctionType()) && "T does not decay");
2160
2161  llvm::FoldingSetNodeID ID;
2162  DecayedType::Profile(ID, T);
2163  void *InsertPos = 0;
2164  if (DecayedType *DT = DecayedTypes.FindNodeOrInsertPos(ID, InsertPos))
2165    return QualType(DT, 0);
2166
2167  QualType Decayed;
2168
2169  // C99 6.7.5.3p7:
2170  //   A declaration of a parameter as "array of type" shall be
2171  //   adjusted to "qualified pointer to type", where the type
2172  //   qualifiers (if any) are those specified within the [ and ] of
2173  //   the array type derivation.
2174  if (T->isArrayType())
2175    Decayed = getArrayDecayedType(T);
2176
2177  // C99 6.7.5.3p8:
2178  //   A declaration of a parameter as "function returning type"
2179  //   shall be adjusted to "pointer to function returning type", as
2180  //   in 6.3.2.1.
2181  if (T->isFunctionType())
2182    Decayed = getPointerType(T);
2183
2184  QualType Canonical = getCanonicalType(Decayed);
2185
2186  // Get the new insert position for the node we care about.
2187  DecayedType *NewIP = DecayedTypes.FindNodeOrInsertPos(ID, InsertPos);
2188  assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2189
2190  DecayedType *New =
2191      new (*this, TypeAlignment) DecayedType(T, Decayed, Canonical);
2192  Types.push_back(New);
2193  DecayedTypes.InsertNode(New, InsertPos);
2194  return QualType(New, 0);
2195}
2196
2197/// getBlockPointerType - Return the uniqued reference to the type for
2198/// a pointer to the specified block.
2199QualType ASTContext::getBlockPointerType(QualType T) const {
2200  assert(T->isFunctionType() && "block of function types only");
2201  // Unique pointers, to guarantee there is only one block of a particular
2202  // structure.
2203  llvm::FoldingSetNodeID ID;
2204  BlockPointerType::Profile(ID, T);
2205
2206  void *InsertPos = 0;
2207  if (BlockPointerType *PT =
2208        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2209    return QualType(PT, 0);
2210
2211  // If the block pointee type isn't canonical, this won't be a canonical
2212  // type either so fill in the canonical type field.
2213  QualType Canonical;
2214  if (!T.isCanonical()) {
2215    Canonical = getBlockPointerType(getCanonicalType(T));
2216
2217    // Get the new insert position for the node we care about.
2218    BlockPointerType *NewIP =
2219      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2220    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2221  }
2222  BlockPointerType *New
2223    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
2224  Types.push_back(New);
2225  BlockPointerTypes.InsertNode(New, InsertPos);
2226  return QualType(New, 0);
2227}
2228
2229/// getLValueReferenceType - Return the uniqued reference to the type for an
2230/// lvalue reference to the specified type.
2231QualType
2232ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
2233  assert(getCanonicalType(T) != OverloadTy &&
2234         "Unresolved overloaded function type");
2235
2236  // Unique pointers, to guarantee there is only one pointer of a particular
2237  // structure.
2238  llvm::FoldingSetNodeID ID;
2239  ReferenceType::Profile(ID, T, SpelledAsLValue);
2240
2241  void *InsertPos = 0;
2242  if (LValueReferenceType *RT =
2243        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
2244    return QualType(RT, 0);
2245
2246  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
2247
2248  // If the referencee type isn't canonical, this won't be a canonical type
2249  // either, so fill in the canonical type field.
2250  QualType Canonical;
2251  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
2252    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
2253    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
2254
2255    // Get the new insert position for the node we care about.
2256    LValueReferenceType *NewIP =
2257      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
2258    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2259  }
2260
2261  LValueReferenceType *New
2262    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
2263                                                     SpelledAsLValue);
2264  Types.push_back(New);
2265  LValueReferenceTypes.InsertNode(New, InsertPos);
2266
2267  return QualType(New, 0);
2268}
2269
2270/// getRValueReferenceType - Return the uniqued reference to the type for an
2271/// rvalue reference to the specified type.
2272QualType ASTContext::getRValueReferenceType(QualType T) const {
2273  // Unique pointers, to guarantee there is only one pointer of a particular
2274  // structure.
2275  llvm::FoldingSetNodeID ID;
2276  ReferenceType::Profile(ID, T, false);
2277
2278  void *InsertPos = 0;
2279  if (RValueReferenceType *RT =
2280        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
2281    return QualType(RT, 0);
2282
2283  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
2284
2285  // If the referencee type isn't canonical, this won't be a canonical type
2286  // either, so fill in the canonical type field.
2287  QualType Canonical;
2288  if (InnerRef || !T.isCanonical()) {
2289    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
2290    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
2291
2292    // Get the new insert position for the node we care about.
2293    RValueReferenceType *NewIP =
2294      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
2295    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2296  }
2297
2298  RValueReferenceType *New
2299    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
2300  Types.push_back(New);
2301  RValueReferenceTypes.InsertNode(New, InsertPos);
2302  return QualType(New, 0);
2303}
2304
2305/// getMemberPointerType - Return the uniqued reference to the type for a
2306/// member pointer to the specified type, in the specified class.
2307QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
2308  // Unique pointers, to guarantee there is only one pointer of a particular
2309  // structure.
2310  llvm::FoldingSetNodeID ID;
2311  MemberPointerType::Profile(ID, T, Cls);
2312
2313  void *InsertPos = 0;
2314  if (MemberPointerType *PT =
2315      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2316    return QualType(PT, 0);
2317
2318  // If the pointee or class type isn't canonical, this won't be a canonical
2319  // type either, so fill in the canonical type field.
2320  QualType Canonical;
2321  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
2322    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
2323
2324    // Get the new insert position for the node we care about.
2325    MemberPointerType *NewIP =
2326      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2327    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2328  }
2329  MemberPointerType *New
2330    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
2331  Types.push_back(New);
2332  MemberPointerTypes.InsertNode(New, InsertPos);
2333  return QualType(New, 0);
2334}
2335
2336/// getConstantArrayType - Return the unique reference to the type for an
2337/// array of the specified element type.
2338QualType ASTContext::getConstantArrayType(QualType EltTy,
2339                                          const llvm::APInt &ArySizeIn,
2340                                          ArrayType::ArraySizeModifier ASM,
2341                                          unsigned IndexTypeQuals) const {
2342  assert((EltTy->isDependentType() ||
2343          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
2344         "Constant array of VLAs is illegal!");
2345
2346  // Convert the array size into a canonical width matching the pointer size for
2347  // the target.
2348  llvm::APInt ArySize(ArySizeIn);
2349  ArySize =
2350    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
2351
2352  llvm::FoldingSetNodeID ID;
2353  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
2354
2355  void *InsertPos = 0;
2356  if (ConstantArrayType *ATP =
2357      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
2358    return QualType(ATP, 0);
2359
2360  // If the element type isn't canonical or has qualifiers, this won't
2361  // be a canonical type either, so fill in the canonical type field.
2362  QualType Canon;
2363  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2364    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2365    Canon = getConstantArrayType(QualType(canonSplit.Ty, 0), ArySize,
2366                                 ASM, IndexTypeQuals);
2367    Canon = getQualifiedType(Canon, canonSplit.Quals);
2368
2369    // Get the new insert position for the node we care about.
2370    ConstantArrayType *NewIP =
2371      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
2372    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2373  }
2374
2375  ConstantArrayType *New = new(*this,TypeAlignment)
2376    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
2377  ConstantArrayTypes.InsertNode(New, InsertPos);
2378  Types.push_back(New);
2379  return QualType(New, 0);
2380}
2381
2382/// getVariableArrayDecayedType - Turns the given type, which may be
2383/// variably-modified, into the corresponding type with all the known
2384/// sizes replaced with [*].
2385QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
2386  // Vastly most common case.
2387  if (!type->isVariablyModifiedType()) return type;
2388
2389  QualType result;
2390
2391  SplitQualType split = type.getSplitDesugaredType();
2392  const Type *ty = split.Ty;
2393  switch (ty->getTypeClass()) {
2394#define TYPE(Class, Base)
2395#define ABSTRACT_TYPE(Class, Base)
2396#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
2397#include "clang/AST/TypeNodes.def"
2398    llvm_unreachable("didn't desugar past all non-canonical types?");
2399
2400  // These types should never be variably-modified.
2401  case Type::Builtin:
2402  case Type::Complex:
2403  case Type::Vector:
2404  case Type::ExtVector:
2405  case Type::DependentSizedExtVector:
2406  case Type::ObjCObject:
2407  case Type::ObjCInterface:
2408  case Type::ObjCObjectPointer:
2409  case Type::Record:
2410  case Type::Enum:
2411  case Type::UnresolvedUsing:
2412  case Type::TypeOfExpr:
2413  case Type::TypeOf:
2414  case Type::Decltype:
2415  case Type::UnaryTransform:
2416  case Type::DependentName:
2417  case Type::InjectedClassName:
2418  case Type::TemplateSpecialization:
2419  case Type::DependentTemplateSpecialization:
2420  case Type::TemplateTypeParm:
2421  case Type::SubstTemplateTypeParmPack:
2422  case Type::Auto:
2423  case Type::PackExpansion:
2424    llvm_unreachable("type should never be variably-modified");
2425
2426  // These types can be variably-modified but should never need to
2427  // further decay.
2428  case Type::FunctionNoProto:
2429  case Type::FunctionProto:
2430  case Type::BlockPointer:
2431  case Type::MemberPointer:
2432    return type;
2433
2434  // These types can be variably-modified.  All these modifications
2435  // preserve structure except as noted by comments.
2436  // TODO: if we ever care about optimizing VLAs, there are no-op
2437  // optimizations available here.
2438  case Type::Pointer:
2439    result = getPointerType(getVariableArrayDecayedType(
2440                              cast<PointerType>(ty)->getPointeeType()));
2441    break;
2442
2443  case Type::LValueReference: {
2444    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
2445    result = getLValueReferenceType(
2446                 getVariableArrayDecayedType(lv->getPointeeType()),
2447                                    lv->isSpelledAsLValue());
2448    break;
2449  }
2450
2451  case Type::RValueReference: {
2452    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
2453    result = getRValueReferenceType(
2454                 getVariableArrayDecayedType(lv->getPointeeType()));
2455    break;
2456  }
2457
2458  case Type::Atomic: {
2459    const AtomicType *at = cast<AtomicType>(ty);
2460    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
2461    break;
2462  }
2463
2464  case Type::ConstantArray: {
2465    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
2466    result = getConstantArrayType(
2467                 getVariableArrayDecayedType(cat->getElementType()),
2468                                  cat->getSize(),
2469                                  cat->getSizeModifier(),
2470                                  cat->getIndexTypeCVRQualifiers());
2471    break;
2472  }
2473
2474  case Type::DependentSizedArray: {
2475    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
2476    result = getDependentSizedArrayType(
2477                 getVariableArrayDecayedType(dat->getElementType()),
2478                                        dat->getSizeExpr(),
2479                                        dat->getSizeModifier(),
2480                                        dat->getIndexTypeCVRQualifiers(),
2481                                        dat->getBracketsRange());
2482    break;
2483  }
2484
2485  // Turn incomplete types into [*] types.
2486  case Type::IncompleteArray: {
2487    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
2488    result = getVariableArrayType(
2489                 getVariableArrayDecayedType(iat->getElementType()),
2490                                  /*size*/ 0,
2491                                  ArrayType::Normal,
2492                                  iat->getIndexTypeCVRQualifiers(),
2493                                  SourceRange());
2494    break;
2495  }
2496
2497  // Turn VLA types into [*] types.
2498  case Type::VariableArray: {
2499    const VariableArrayType *vat = cast<VariableArrayType>(ty);
2500    result = getVariableArrayType(
2501                 getVariableArrayDecayedType(vat->getElementType()),
2502                                  /*size*/ 0,
2503                                  ArrayType::Star,
2504                                  vat->getIndexTypeCVRQualifiers(),
2505                                  vat->getBracketsRange());
2506    break;
2507  }
2508  }
2509
2510  // Apply the top-level qualifiers from the original.
2511  return getQualifiedType(result, split.Quals);
2512}
2513
2514/// getVariableArrayType - Returns a non-unique reference to the type for a
2515/// variable array of the specified element type.
2516QualType ASTContext::getVariableArrayType(QualType EltTy,
2517                                          Expr *NumElts,
2518                                          ArrayType::ArraySizeModifier ASM,
2519                                          unsigned IndexTypeQuals,
2520                                          SourceRange Brackets) const {
2521  // Since we don't unique expressions, it isn't possible to unique VLA's
2522  // that have an expression provided for their size.
2523  QualType Canon;
2524
2525  // Be sure to pull qualifiers off the element type.
2526  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2527    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2528    Canon = getVariableArrayType(QualType(canonSplit.Ty, 0), NumElts, ASM,
2529                                 IndexTypeQuals, Brackets);
2530    Canon = getQualifiedType(Canon, canonSplit.Quals);
2531  }
2532
2533  VariableArrayType *New = new(*this, TypeAlignment)
2534    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
2535
2536  VariableArrayTypes.push_back(New);
2537  Types.push_back(New);
2538  return QualType(New, 0);
2539}
2540
2541/// getDependentSizedArrayType - Returns a non-unique reference to
2542/// the type for a dependently-sized array of the specified element
2543/// type.
2544QualType ASTContext::getDependentSizedArrayType(QualType elementType,
2545                                                Expr *numElements,
2546                                                ArrayType::ArraySizeModifier ASM,
2547                                                unsigned elementTypeQuals,
2548                                                SourceRange brackets) const {
2549  assert((!numElements || numElements->isTypeDependent() ||
2550          numElements->isValueDependent()) &&
2551         "Size must be type- or value-dependent!");
2552
2553  // Dependently-sized array types that do not have a specified number
2554  // of elements will have their sizes deduced from a dependent
2555  // initializer.  We do no canonicalization here at all, which is okay
2556  // because they can't be used in most locations.
2557  if (!numElements) {
2558    DependentSizedArrayType *newType
2559      = new (*this, TypeAlignment)
2560          DependentSizedArrayType(*this, elementType, QualType(),
2561                                  numElements, ASM, elementTypeQuals,
2562                                  brackets);
2563    Types.push_back(newType);
2564    return QualType(newType, 0);
2565  }
2566
2567  // Otherwise, we actually build a new type every time, but we
2568  // also build a canonical type.
2569
2570  SplitQualType canonElementType = getCanonicalType(elementType).split();
2571
2572  void *insertPos = 0;
2573  llvm::FoldingSetNodeID ID;
2574  DependentSizedArrayType::Profile(ID, *this,
2575                                   QualType(canonElementType.Ty, 0),
2576                                   ASM, elementTypeQuals, numElements);
2577
2578  // Look for an existing type with these properties.
2579  DependentSizedArrayType *canonTy =
2580    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2581
2582  // If we don't have one, build one.
2583  if (!canonTy) {
2584    canonTy = new (*this, TypeAlignment)
2585      DependentSizedArrayType(*this, QualType(canonElementType.Ty, 0),
2586                              QualType(), numElements, ASM, elementTypeQuals,
2587                              brackets);
2588    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
2589    Types.push_back(canonTy);
2590  }
2591
2592  // Apply qualifiers from the element type to the array.
2593  QualType canon = getQualifiedType(QualType(canonTy,0),
2594                                    canonElementType.Quals);
2595
2596  // If we didn't need extra canonicalization for the element type,
2597  // then just use that as our result.
2598  if (QualType(canonElementType.Ty, 0) == elementType)
2599    return canon;
2600
2601  // Otherwise, we need to build a type which follows the spelling
2602  // of the element type.
2603  DependentSizedArrayType *sugaredType
2604    = new (*this, TypeAlignment)
2605        DependentSizedArrayType(*this, elementType, canon, numElements,
2606                                ASM, elementTypeQuals, brackets);
2607  Types.push_back(sugaredType);
2608  return QualType(sugaredType, 0);
2609}
2610
2611QualType ASTContext::getIncompleteArrayType(QualType elementType,
2612                                            ArrayType::ArraySizeModifier ASM,
2613                                            unsigned elementTypeQuals) const {
2614  llvm::FoldingSetNodeID ID;
2615  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
2616
2617  void *insertPos = 0;
2618  if (IncompleteArrayType *iat =
2619       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
2620    return QualType(iat, 0);
2621
2622  // If the element type isn't canonical, this won't be a canonical type
2623  // either, so fill in the canonical type field.  We also have to pull
2624  // qualifiers off the element type.
2625  QualType canon;
2626
2627  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
2628    SplitQualType canonSplit = getCanonicalType(elementType).split();
2629    canon = getIncompleteArrayType(QualType(canonSplit.Ty, 0),
2630                                   ASM, elementTypeQuals);
2631    canon = getQualifiedType(canon, canonSplit.Quals);
2632
2633    // Get the new insert position for the node we care about.
2634    IncompleteArrayType *existing =
2635      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2636    assert(!existing && "Shouldn't be in the map!"); (void) existing;
2637  }
2638
2639  IncompleteArrayType *newType = new (*this, TypeAlignment)
2640    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
2641
2642  IncompleteArrayTypes.InsertNode(newType, insertPos);
2643  Types.push_back(newType);
2644  return QualType(newType, 0);
2645}
2646
2647/// getVectorType - Return the unique reference to a vector type of
2648/// the specified element type and size. VectorType must be a built-in type.
2649QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
2650                                   VectorType::VectorKind VecKind) const {
2651  assert(vecType->isBuiltinType());
2652
2653  // Check if we've already instantiated a vector of this type.
2654  llvm::FoldingSetNodeID ID;
2655  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
2656
2657  void *InsertPos = 0;
2658  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2659    return QualType(VTP, 0);
2660
2661  // If the element type isn't canonical, this won't be a canonical type either,
2662  // so fill in the canonical type field.
2663  QualType Canonical;
2664  if (!vecType.isCanonical()) {
2665    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
2666
2667    // Get the new insert position for the node we care about.
2668    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2669    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2670  }
2671  VectorType *New = new (*this, TypeAlignment)
2672    VectorType(vecType, NumElts, Canonical, VecKind);
2673  VectorTypes.InsertNode(New, InsertPos);
2674  Types.push_back(New);
2675  return QualType(New, 0);
2676}
2677
2678/// getExtVectorType - Return the unique reference to an extended vector type of
2679/// the specified element type and size. VectorType must be a built-in type.
2680QualType
2681ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
2682  assert(vecType->isBuiltinType() || vecType->isDependentType());
2683
2684  // Check if we've already instantiated a vector of this type.
2685  llvm::FoldingSetNodeID ID;
2686  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
2687                      VectorType::GenericVector);
2688  void *InsertPos = 0;
2689  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2690    return QualType(VTP, 0);
2691
2692  // If the element type isn't canonical, this won't be a canonical type either,
2693  // so fill in the canonical type field.
2694  QualType Canonical;
2695  if (!vecType.isCanonical()) {
2696    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
2697
2698    // Get the new insert position for the node we care about.
2699    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2700    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2701  }
2702  ExtVectorType *New = new (*this, TypeAlignment)
2703    ExtVectorType(vecType, NumElts, Canonical);
2704  VectorTypes.InsertNode(New, InsertPos);
2705  Types.push_back(New);
2706  return QualType(New, 0);
2707}
2708
2709QualType
2710ASTContext::getDependentSizedExtVectorType(QualType vecType,
2711                                           Expr *SizeExpr,
2712                                           SourceLocation AttrLoc) const {
2713  llvm::FoldingSetNodeID ID;
2714  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
2715                                       SizeExpr);
2716
2717  void *InsertPos = 0;
2718  DependentSizedExtVectorType *Canon
2719    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2720  DependentSizedExtVectorType *New;
2721  if (Canon) {
2722    // We already have a canonical version of this array type; use it as
2723    // the canonical type for a newly-built type.
2724    New = new (*this, TypeAlignment)
2725      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
2726                                  SizeExpr, AttrLoc);
2727  } else {
2728    QualType CanonVecTy = getCanonicalType(vecType);
2729    if (CanonVecTy == vecType) {
2730      New = new (*this, TypeAlignment)
2731        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
2732                                    AttrLoc);
2733
2734      DependentSizedExtVectorType *CanonCheck
2735        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2736      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
2737      (void)CanonCheck;
2738      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
2739    } else {
2740      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
2741                                                      SourceLocation());
2742      New = new (*this, TypeAlignment)
2743        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2744    }
2745  }
2746
2747  Types.push_back(New);
2748  return QualType(New, 0);
2749}
2750
2751/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
2752///
2753QualType
2754ASTContext::getFunctionNoProtoType(QualType ResultTy,
2755                                   const FunctionType::ExtInfo &Info) const {
2756  const CallingConv CallConv = Info.getCC();
2757
2758  // Unique functions, to guarantee there is only one function of a particular
2759  // structure.
2760  llvm::FoldingSetNodeID ID;
2761  FunctionNoProtoType::Profile(ID, ResultTy, Info);
2762
2763  void *InsertPos = 0;
2764  if (FunctionNoProtoType *FT =
2765        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2766    return QualType(FT, 0);
2767
2768  QualType Canonical;
2769  if (!ResultTy.isCanonical()) {
2770    Canonical = getFunctionNoProtoType(getCanonicalType(ResultTy), Info);
2771
2772    // Get the new insert position for the node we care about.
2773    FunctionNoProtoType *NewIP =
2774      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2775    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2776  }
2777
2778  FunctionProtoType::ExtInfo newInfo = Info.withCallingConv(CallConv);
2779  FunctionNoProtoType *New = new (*this, TypeAlignment)
2780    FunctionNoProtoType(ResultTy, Canonical, newInfo);
2781  Types.push_back(New);
2782  FunctionNoProtoTypes.InsertNode(New, InsertPos);
2783  return QualType(New, 0);
2784}
2785
2786/// \brief Determine whether \p T is canonical as the result type of a function.
2787static bool isCanonicalResultType(QualType T) {
2788  return T.isCanonical() &&
2789         (T.getObjCLifetime() == Qualifiers::OCL_None ||
2790          T.getObjCLifetime() == Qualifiers::OCL_ExplicitNone);
2791}
2792
2793/// getFunctionType - Return a normal function type with a typed argument
2794/// list.  isVariadic indicates whether the argument list includes '...'.
2795QualType
2796ASTContext::getFunctionType(QualType ResultTy, ArrayRef<QualType> ArgArray,
2797                            const FunctionProtoType::ExtProtoInfo &EPI) const {
2798  size_t NumArgs = ArgArray.size();
2799
2800  // Unique functions, to guarantee there is only one function of a particular
2801  // structure.
2802  llvm::FoldingSetNodeID ID;
2803  FunctionProtoType::Profile(ID, ResultTy, ArgArray.begin(), NumArgs, EPI,
2804                             *this);
2805
2806  void *InsertPos = 0;
2807  if (FunctionProtoType *FTP =
2808        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2809    return QualType(FTP, 0);
2810
2811  // Determine whether the type being created is already canonical or not.
2812  bool isCanonical =
2813    EPI.ExceptionSpecType == EST_None && isCanonicalResultType(ResultTy) &&
2814    !EPI.HasTrailingReturn;
2815  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
2816    if (!ArgArray[i].isCanonicalAsParam())
2817      isCanonical = false;
2818
2819  // If this type isn't canonical, get the canonical version of it.
2820  // The exception spec is not part of the canonical type.
2821  QualType Canonical;
2822  if (!isCanonical) {
2823    SmallVector<QualType, 16> CanonicalArgs;
2824    CanonicalArgs.reserve(NumArgs);
2825    for (unsigned i = 0; i != NumArgs; ++i)
2826      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
2827
2828    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
2829    CanonicalEPI.HasTrailingReturn = false;
2830    CanonicalEPI.ExceptionSpecType = EST_None;
2831    CanonicalEPI.NumExceptions = 0;
2832
2833    // Result types do not have ARC lifetime qualifiers.
2834    QualType CanResultTy = getCanonicalType(ResultTy);
2835    if (ResultTy.getQualifiers().hasObjCLifetime()) {
2836      Qualifiers Qs = CanResultTy.getQualifiers();
2837      Qs.removeObjCLifetime();
2838      CanResultTy = getQualifiedType(CanResultTy.getUnqualifiedType(), Qs);
2839    }
2840
2841    Canonical = getFunctionType(CanResultTy, CanonicalArgs, CanonicalEPI);
2842
2843    // Get the new insert position for the node we care about.
2844    FunctionProtoType *NewIP =
2845      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2846    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2847  }
2848
2849  // FunctionProtoType objects are allocated with extra bytes after
2850  // them for three variable size arrays at the end:
2851  //  - parameter types
2852  //  - exception types
2853  //  - consumed-arguments flags
2854  // Instead of the exception types, there could be a noexcept
2855  // expression, or information used to resolve the exception
2856  // specification.
2857  size_t Size = sizeof(FunctionProtoType) +
2858                NumArgs * sizeof(QualType);
2859  if (EPI.ExceptionSpecType == EST_Dynamic) {
2860    Size += EPI.NumExceptions * sizeof(QualType);
2861  } else if (EPI.ExceptionSpecType == EST_ComputedNoexcept) {
2862    Size += sizeof(Expr*);
2863  } else if (EPI.ExceptionSpecType == EST_Uninstantiated) {
2864    Size += 2 * sizeof(FunctionDecl*);
2865  } else if (EPI.ExceptionSpecType == EST_Unevaluated) {
2866    Size += sizeof(FunctionDecl*);
2867  }
2868  if (EPI.ConsumedArguments)
2869    Size += NumArgs * sizeof(bool);
2870
2871  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
2872  FunctionProtoType::ExtProtoInfo newEPI = EPI;
2873  new (FTP) FunctionProtoType(ResultTy, ArgArray, Canonical, newEPI);
2874  Types.push_back(FTP);
2875  FunctionProtoTypes.InsertNode(FTP, InsertPos);
2876  return QualType(FTP, 0);
2877}
2878
2879#ifndef NDEBUG
2880static bool NeedsInjectedClassNameType(const RecordDecl *D) {
2881  if (!isa<CXXRecordDecl>(D)) return false;
2882  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
2883  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
2884    return true;
2885  if (RD->getDescribedClassTemplate() &&
2886      !isa<ClassTemplateSpecializationDecl>(RD))
2887    return true;
2888  return false;
2889}
2890#endif
2891
2892/// getInjectedClassNameType - Return the unique reference to the
2893/// injected class name type for the specified templated declaration.
2894QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
2895                                              QualType TST) const {
2896  assert(NeedsInjectedClassNameType(Decl));
2897  if (Decl->TypeForDecl) {
2898    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2899  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDecl()) {
2900    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
2901    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2902    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2903  } else {
2904    Type *newType =
2905      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
2906    Decl->TypeForDecl = newType;
2907    Types.push_back(newType);
2908  }
2909  return QualType(Decl->TypeForDecl, 0);
2910}
2911
2912/// getTypeDeclType - Return the unique reference to the type for the
2913/// specified type declaration.
2914QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) const {
2915  assert(Decl && "Passed null for Decl param");
2916  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
2917
2918  if (const TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Decl))
2919    return getTypedefType(Typedef);
2920
2921  assert(!isa<TemplateTypeParmDecl>(Decl) &&
2922         "Template type parameter types are always available.");
2923
2924  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
2925    assert(!Record->getPreviousDecl() &&
2926           "struct/union has previous declaration");
2927    assert(!NeedsInjectedClassNameType(Record));
2928    return getRecordType(Record);
2929  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
2930    assert(!Enum->getPreviousDecl() &&
2931           "enum has previous declaration");
2932    return getEnumType(Enum);
2933  } else if (const UnresolvedUsingTypenameDecl *Using =
2934               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
2935    Type *newType = new (*this, TypeAlignment) UnresolvedUsingType(Using);
2936    Decl->TypeForDecl = newType;
2937    Types.push_back(newType);
2938  } else
2939    llvm_unreachable("TypeDecl without a type?");
2940
2941  return QualType(Decl->TypeForDecl, 0);
2942}
2943
2944/// getTypedefType - Return the unique reference to the type for the
2945/// specified typedef name decl.
2946QualType
2947ASTContext::getTypedefType(const TypedefNameDecl *Decl,
2948                           QualType Canonical) const {
2949  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2950
2951  if (Canonical.isNull())
2952    Canonical = getCanonicalType(Decl->getUnderlyingType());
2953  TypedefType *newType = new(*this, TypeAlignment)
2954    TypedefType(Type::Typedef, Decl, Canonical);
2955  Decl->TypeForDecl = newType;
2956  Types.push_back(newType);
2957  return QualType(newType, 0);
2958}
2959
2960QualType ASTContext::getRecordType(const RecordDecl *Decl) const {
2961  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2962
2963  if (const RecordDecl *PrevDecl = Decl->getPreviousDecl())
2964    if (PrevDecl->TypeForDecl)
2965      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2966
2967  RecordType *newType = new (*this, TypeAlignment) RecordType(Decl);
2968  Decl->TypeForDecl = newType;
2969  Types.push_back(newType);
2970  return QualType(newType, 0);
2971}
2972
2973QualType ASTContext::getEnumType(const EnumDecl *Decl) const {
2974  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2975
2976  if (const EnumDecl *PrevDecl = Decl->getPreviousDecl())
2977    if (PrevDecl->TypeForDecl)
2978      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2979
2980  EnumType *newType = new (*this, TypeAlignment) EnumType(Decl);
2981  Decl->TypeForDecl = newType;
2982  Types.push_back(newType);
2983  return QualType(newType, 0);
2984}
2985
2986QualType ASTContext::getAttributedType(AttributedType::Kind attrKind,
2987                                       QualType modifiedType,
2988                                       QualType equivalentType) {
2989  llvm::FoldingSetNodeID id;
2990  AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
2991
2992  void *insertPos = 0;
2993  AttributedType *type = AttributedTypes.FindNodeOrInsertPos(id, insertPos);
2994  if (type) return QualType(type, 0);
2995
2996  QualType canon = getCanonicalType(equivalentType);
2997  type = new (*this, TypeAlignment)
2998           AttributedType(canon, attrKind, modifiedType, equivalentType);
2999
3000  Types.push_back(type);
3001  AttributedTypes.InsertNode(type, insertPos);
3002
3003  return QualType(type, 0);
3004}
3005
3006
3007/// \brief Retrieve a substitution-result type.
3008QualType
3009ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
3010                                         QualType Replacement) const {
3011  assert(Replacement.isCanonical()
3012         && "replacement types must always be canonical");
3013
3014  llvm::FoldingSetNodeID ID;
3015  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
3016  void *InsertPos = 0;
3017  SubstTemplateTypeParmType *SubstParm
3018    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
3019
3020  if (!SubstParm) {
3021    SubstParm = new (*this, TypeAlignment)
3022      SubstTemplateTypeParmType(Parm, Replacement);
3023    Types.push_back(SubstParm);
3024    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
3025  }
3026
3027  return QualType(SubstParm, 0);
3028}
3029
3030/// \brief Retrieve a
3031QualType ASTContext::getSubstTemplateTypeParmPackType(
3032                                          const TemplateTypeParmType *Parm,
3033                                              const TemplateArgument &ArgPack) {
3034#ifndef NDEBUG
3035  for (TemplateArgument::pack_iterator P = ArgPack.pack_begin(),
3036                                    PEnd = ArgPack.pack_end();
3037       P != PEnd; ++P) {
3038    assert(P->getKind() == TemplateArgument::Type &&"Pack contains a non-type");
3039    assert(P->getAsType().isCanonical() && "Pack contains non-canonical type");
3040  }
3041#endif
3042
3043  llvm::FoldingSetNodeID ID;
3044  SubstTemplateTypeParmPackType::Profile(ID, Parm, ArgPack);
3045  void *InsertPos = 0;
3046  if (SubstTemplateTypeParmPackType *SubstParm
3047        = SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos))
3048    return QualType(SubstParm, 0);
3049
3050  QualType Canon;
3051  if (!Parm->isCanonicalUnqualified()) {
3052    Canon = getCanonicalType(QualType(Parm, 0));
3053    Canon = getSubstTemplateTypeParmPackType(cast<TemplateTypeParmType>(Canon),
3054                                             ArgPack);
3055    SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos);
3056  }
3057
3058  SubstTemplateTypeParmPackType *SubstParm
3059    = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
3060                                                               ArgPack);
3061  Types.push_back(SubstParm);
3062  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
3063  return QualType(SubstParm, 0);
3064}
3065
3066/// \brief Retrieve the template type parameter type for a template
3067/// parameter or parameter pack with the given depth, index, and (optionally)
3068/// name.
3069QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
3070                                             bool ParameterPack,
3071                                             TemplateTypeParmDecl *TTPDecl) const {
3072  llvm::FoldingSetNodeID ID;
3073  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, TTPDecl);
3074  void *InsertPos = 0;
3075  TemplateTypeParmType *TypeParm
3076    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
3077
3078  if (TypeParm)
3079    return QualType(TypeParm, 0);
3080
3081  if (TTPDecl) {
3082    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
3083    TypeParm = new (*this, TypeAlignment) TemplateTypeParmType(TTPDecl, Canon);
3084
3085    TemplateTypeParmType *TypeCheck
3086      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
3087    assert(!TypeCheck && "Template type parameter canonical type broken");
3088    (void)TypeCheck;
3089  } else
3090    TypeParm = new (*this, TypeAlignment)
3091      TemplateTypeParmType(Depth, Index, ParameterPack);
3092
3093  Types.push_back(TypeParm);
3094  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
3095
3096  return QualType(TypeParm, 0);
3097}
3098
3099TypeSourceInfo *
3100ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
3101                                              SourceLocation NameLoc,
3102                                        const TemplateArgumentListInfo &Args,
3103                                              QualType Underlying) const {
3104  assert(!Name.getAsDependentTemplateName() &&
3105         "No dependent template names here!");
3106  QualType TST = getTemplateSpecializationType(Name, Args, Underlying);
3107
3108  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
3109  TemplateSpecializationTypeLoc TL =
3110      DI->getTypeLoc().castAs<TemplateSpecializationTypeLoc>();
3111  TL.setTemplateKeywordLoc(SourceLocation());
3112  TL.setTemplateNameLoc(NameLoc);
3113  TL.setLAngleLoc(Args.getLAngleLoc());
3114  TL.setRAngleLoc(Args.getRAngleLoc());
3115  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
3116    TL.setArgLocInfo(i, Args[i].getLocInfo());
3117  return DI;
3118}
3119
3120QualType
3121ASTContext::getTemplateSpecializationType(TemplateName Template,
3122                                          const TemplateArgumentListInfo &Args,
3123                                          QualType Underlying) const {
3124  assert(!Template.getAsDependentTemplateName() &&
3125         "No dependent template names here!");
3126
3127  unsigned NumArgs = Args.size();
3128
3129  SmallVector<TemplateArgument, 4> ArgVec;
3130  ArgVec.reserve(NumArgs);
3131  for (unsigned i = 0; i != NumArgs; ++i)
3132    ArgVec.push_back(Args[i].getArgument());
3133
3134  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
3135                                       Underlying);
3136}
3137
3138#ifndef NDEBUG
3139static bool hasAnyPackExpansions(const TemplateArgument *Args,
3140                                 unsigned NumArgs) {
3141  for (unsigned I = 0; I != NumArgs; ++I)
3142    if (Args[I].isPackExpansion())
3143      return true;
3144
3145  return true;
3146}
3147#endif
3148
3149QualType
3150ASTContext::getTemplateSpecializationType(TemplateName Template,
3151                                          const TemplateArgument *Args,
3152                                          unsigned NumArgs,
3153                                          QualType Underlying) const {
3154  assert(!Template.getAsDependentTemplateName() &&
3155         "No dependent template names here!");
3156  // Look through qualified template names.
3157  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
3158    Template = TemplateName(QTN->getTemplateDecl());
3159
3160  bool IsTypeAlias =
3161    Template.getAsTemplateDecl() &&
3162    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
3163  QualType CanonType;
3164  if (!Underlying.isNull())
3165    CanonType = getCanonicalType(Underlying);
3166  else {
3167    // We can get here with an alias template when the specialization contains
3168    // a pack expansion that does not match up with a parameter pack.
3169    assert((!IsTypeAlias || hasAnyPackExpansions(Args, NumArgs)) &&
3170           "Caller must compute aliased type");
3171    IsTypeAlias = false;
3172    CanonType = getCanonicalTemplateSpecializationType(Template, Args,
3173                                                       NumArgs);
3174  }
3175
3176  // Allocate the (non-canonical) template specialization type, but don't
3177  // try to unique it: these types typically have location information that
3178  // we don't unique and don't want to lose.
3179  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
3180                       sizeof(TemplateArgument) * NumArgs +
3181                       (IsTypeAlias? sizeof(QualType) : 0),
3182                       TypeAlignment);
3183  TemplateSpecializationType *Spec
3184    = new (Mem) TemplateSpecializationType(Template, Args, NumArgs, CanonType,
3185                                         IsTypeAlias ? Underlying : QualType());
3186
3187  Types.push_back(Spec);
3188  return QualType(Spec, 0);
3189}
3190
3191QualType
3192ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
3193                                                   const TemplateArgument *Args,
3194                                                   unsigned NumArgs) const {
3195  assert(!Template.getAsDependentTemplateName() &&
3196         "No dependent template names here!");
3197
3198  // Look through qualified template names.
3199  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
3200    Template = TemplateName(QTN->getTemplateDecl());
3201
3202  // Build the canonical template specialization type.
3203  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
3204  SmallVector<TemplateArgument, 4> CanonArgs;
3205  CanonArgs.reserve(NumArgs);
3206  for (unsigned I = 0; I != NumArgs; ++I)
3207    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
3208
3209  // Determine whether this canonical template specialization type already
3210  // exists.
3211  llvm::FoldingSetNodeID ID;
3212  TemplateSpecializationType::Profile(ID, CanonTemplate,
3213                                      CanonArgs.data(), NumArgs, *this);
3214
3215  void *InsertPos = 0;
3216  TemplateSpecializationType *Spec
3217    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3218
3219  if (!Spec) {
3220    // Allocate a new canonical template specialization type.
3221    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
3222                          sizeof(TemplateArgument) * NumArgs),
3223                         TypeAlignment);
3224    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
3225                                                CanonArgs.data(), NumArgs,
3226                                                QualType(), QualType());
3227    Types.push_back(Spec);
3228    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
3229  }
3230
3231  assert(Spec->isDependentType() &&
3232         "Non-dependent template-id type must have a canonical type");
3233  return QualType(Spec, 0);
3234}
3235
3236QualType
3237ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
3238                              NestedNameSpecifier *NNS,
3239                              QualType NamedType) const {
3240  llvm::FoldingSetNodeID ID;
3241  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
3242
3243  void *InsertPos = 0;
3244  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
3245  if (T)
3246    return QualType(T, 0);
3247
3248  QualType Canon = NamedType;
3249  if (!Canon.isCanonical()) {
3250    Canon = getCanonicalType(NamedType);
3251    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
3252    assert(!CheckT && "Elaborated canonical type broken");
3253    (void)CheckT;
3254  }
3255
3256  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
3257  Types.push_back(T);
3258  ElaboratedTypes.InsertNode(T, InsertPos);
3259  return QualType(T, 0);
3260}
3261
3262QualType
3263ASTContext::getParenType(QualType InnerType) const {
3264  llvm::FoldingSetNodeID ID;
3265  ParenType::Profile(ID, InnerType);
3266
3267  void *InsertPos = 0;
3268  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
3269  if (T)
3270    return QualType(T, 0);
3271
3272  QualType Canon = InnerType;
3273  if (!Canon.isCanonical()) {
3274    Canon = getCanonicalType(InnerType);
3275    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
3276    assert(!CheckT && "Paren canonical type broken");
3277    (void)CheckT;
3278  }
3279
3280  T = new (*this) ParenType(InnerType, Canon);
3281  Types.push_back(T);
3282  ParenTypes.InsertNode(T, InsertPos);
3283  return QualType(T, 0);
3284}
3285
3286QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
3287                                          NestedNameSpecifier *NNS,
3288                                          const IdentifierInfo *Name,
3289                                          QualType Canon) const {
3290  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
3291
3292  if (Canon.isNull()) {
3293    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
3294    ElaboratedTypeKeyword CanonKeyword = Keyword;
3295    if (Keyword == ETK_None)
3296      CanonKeyword = ETK_Typename;
3297
3298    if (CanonNNS != NNS || CanonKeyword != Keyword)
3299      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
3300  }
3301
3302  llvm::FoldingSetNodeID ID;
3303  DependentNameType::Profile(ID, Keyword, NNS, Name);
3304
3305  void *InsertPos = 0;
3306  DependentNameType *T
3307    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
3308  if (T)
3309    return QualType(T, 0);
3310
3311  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
3312  Types.push_back(T);
3313  DependentNameTypes.InsertNode(T, InsertPos);
3314  return QualType(T, 0);
3315}
3316
3317QualType
3318ASTContext::getDependentTemplateSpecializationType(
3319                                 ElaboratedTypeKeyword Keyword,
3320                                 NestedNameSpecifier *NNS,
3321                                 const IdentifierInfo *Name,
3322                                 const TemplateArgumentListInfo &Args) const {
3323  // TODO: avoid this copy
3324  SmallVector<TemplateArgument, 16> ArgCopy;
3325  for (unsigned I = 0, E = Args.size(); I != E; ++I)
3326    ArgCopy.push_back(Args[I].getArgument());
3327  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
3328                                                ArgCopy.size(),
3329                                                ArgCopy.data());
3330}
3331
3332QualType
3333ASTContext::getDependentTemplateSpecializationType(
3334                                 ElaboratedTypeKeyword Keyword,
3335                                 NestedNameSpecifier *NNS,
3336                                 const IdentifierInfo *Name,
3337                                 unsigned NumArgs,
3338                                 const TemplateArgument *Args) const {
3339  assert((!NNS || NNS->isDependent()) &&
3340         "nested-name-specifier must be dependent");
3341
3342  llvm::FoldingSetNodeID ID;
3343  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
3344                                               Name, NumArgs, Args);
3345
3346  void *InsertPos = 0;
3347  DependentTemplateSpecializationType *T
3348    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3349  if (T)
3350    return QualType(T, 0);
3351
3352  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
3353
3354  ElaboratedTypeKeyword CanonKeyword = Keyword;
3355  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
3356
3357  bool AnyNonCanonArgs = false;
3358  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
3359  for (unsigned I = 0; I != NumArgs; ++I) {
3360    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
3361    if (!CanonArgs[I].structurallyEquals(Args[I]))
3362      AnyNonCanonArgs = true;
3363  }
3364
3365  QualType Canon;
3366  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
3367    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
3368                                                   Name, NumArgs,
3369                                                   CanonArgs.data());
3370
3371    // Find the insert position again.
3372    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3373  }
3374
3375  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
3376                        sizeof(TemplateArgument) * NumArgs),
3377                       TypeAlignment);
3378  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
3379                                                    Name, NumArgs, Args, Canon);
3380  Types.push_back(T);
3381  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
3382  return QualType(T, 0);
3383}
3384
3385QualType ASTContext::getPackExpansionType(QualType Pattern,
3386                                          Optional<unsigned> NumExpansions) {
3387  llvm::FoldingSetNodeID ID;
3388  PackExpansionType::Profile(ID, Pattern, NumExpansions);
3389
3390  assert(Pattern->containsUnexpandedParameterPack() &&
3391         "Pack expansions must expand one or more parameter packs");
3392  void *InsertPos = 0;
3393  PackExpansionType *T
3394    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3395  if (T)
3396    return QualType(T, 0);
3397
3398  QualType Canon;
3399  if (!Pattern.isCanonical()) {
3400    Canon = getCanonicalType(Pattern);
3401    // The canonical type might not contain an unexpanded parameter pack, if it
3402    // contains an alias template specialization which ignores one of its
3403    // parameters.
3404    if (Canon->containsUnexpandedParameterPack()) {
3405      Canon = getPackExpansionType(getCanonicalType(Pattern), NumExpansions);
3406
3407      // Find the insert position again, in case we inserted an element into
3408      // PackExpansionTypes and invalidated our insert position.
3409      PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3410    }
3411  }
3412
3413  T = new (*this) PackExpansionType(Pattern, Canon, NumExpansions);
3414  Types.push_back(T);
3415  PackExpansionTypes.InsertNode(T, InsertPos);
3416  return QualType(T, 0);
3417}
3418
3419/// CmpProtocolNames - Comparison predicate for sorting protocols
3420/// alphabetically.
3421static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
3422                            const ObjCProtocolDecl *RHS) {
3423  return LHS->getDeclName() < RHS->getDeclName();
3424}
3425
3426static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
3427                                unsigned NumProtocols) {
3428  if (NumProtocols == 0) return true;
3429
3430  if (Protocols[0]->getCanonicalDecl() != Protocols[0])
3431    return false;
3432
3433  for (unsigned i = 1; i != NumProtocols; ++i)
3434    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]) ||
3435        Protocols[i]->getCanonicalDecl() != Protocols[i])
3436      return false;
3437  return true;
3438}
3439
3440static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
3441                                   unsigned &NumProtocols) {
3442  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
3443
3444  // Sort protocols, keyed by name.
3445  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
3446
3447  // Canonicalize.
3448  for (unsigned I = 0, N = NumProtocols; I != N; ++I)
3449    Protocols[I] = Protocols[I]->getCanonicalDecl();
3450
3451  // Remove duplicates.
3452  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
3453  NumProtocols = ProtocolsEnd-Protocols;
3454}
3455
3456QualType ASTContext::getObjCObjectType(QualType BaseType,
3457                                       ObjCProtocolDecl * const *Protocols,
3458                                       unsigned NumProtocols) const {
3459  // If the base type is an interface and there aren't any protocols
3460  // to add, then the interface type will do just fine.
3461  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
3462    return BaseType;
3463
3464  // Look in the folding set for an existing type.
3465  llvm::FoldingSetNodeID ID;
3466  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
3467  void *InsertPos = 0;
3468  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
3469    return QualType(QT, 0);
3470
3471  // Build the canonical type, which has the canonical base type and
3472  // a sorted-and-uniqued list of protocols.
3473  QualType Canonical;
3474  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
3475  if (!ProtocolsSorted || !BaseType.isCanonical()) {
3476    if (!ProtocolsSorted) {
3477      SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
3478                                                     Protocols + NumProtocols);
3479      unsigned UniqueCount = NumProtocols;
3480
3481      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
3482      Canonical = getObjCObjectType(getCanonicalType(BaseType),
3483                                    &Sorted[0], UniqueCount);
3484    } else {
3485      Canonical = getObjCObjectType(getCanonicalType(BaseType),
3486                                    Protocols, NumProtocols);
3487    }
3488
3489    // Regenerate InsertPos.
3490    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
3491  }
3492
3493  unsigned Size = sizeof(ObjCObjectTypeImpl);
3494  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
3495  void *Mem = Allocate(Size, TypeAlignment);
3496  ObjCObjectTypeImpl *T =
3497    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
3498
3499  Types.push_back(T);
3500  ObjCObjectTypes.InsertNode(T, InsertPos);
3501  return QualType(T, 0);
3502}
3503
3504/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
3505/// the given object type.
3506QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
3507  llvm::FoldingSetNodeID ID;
3508  ObjCObjectPointerType::Profile(ID, ObjectT);
3509
3510  void *InsertPos = 0;
3511  if (ObjCObjectPointerType *QT =
3512              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
3513    return QualType(QT, 0);
3514
3515  // Find the canonical object type.
3516  QualType Canonical;
3517  if (!ObjectT.isCanonical()) {
3518    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
3519
3520    // Regenerate InsertPos.
3521    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
3522  }
3523
3524  // No match.
3525  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
3526  ObjCObjectPointerType *QType =
3527    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
3528
3529  Types.push_back(QType);
3530  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
3531  return QualType(QType, 0);
3532}
3533
3534/// getObjCInterfaceType - Return the unique reference to the type for the
3535/// specified ObjC interface decl. The list of protocols is optional.
3536QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
3537                                          ObjCInterfaceDecl *PrevDecl) const {
3538  if (Decl->TypeForDecl)
3539    return QualType(Decl->TypeForDecl, 0);
3540
3541  if (PrevDecl) {
3542    assert(PrevDecl->TypeForDecl && "previous decl has no TypeForDecl");
3543    Decl->TypeForDecl = PrevDecl->TypeForDecl;
3544    return QualType(PrevDecl->TypeForDecl, 0);
3545  }
3546
3547  // Prefer the definition, if there is one.
3548  if (const ObjCInterfaceDecl *Def = Decl->getDefinition())
3549    Decl = Def;
3550
3551  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
3552  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
3553  Decl->TypeForDecl = T;
3554  Types.push_back(T);
3555  return QualType(T, 0);
3556}
3557
3558/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
3559/// TypeOfExprType AST's (since expression's are never shared). For example,
3560/// multiple declarations that refer to "typeof(x)" all contain different
3561/// DeclRefExpr's. This doesn't effect the type checker, since it operates
3562/// on canonical type's (which are always unique).
3563QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
3564  TypeOfExprType *toe;
3565  if (tofExpr->isTypeDependent()) {
3566    llvm::FoldingSetNodeID ID;
3567    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
3568
3569    void *InsertPos = 0;
3570    DependentTypeOfExprType *Canon
3571      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
3572    if (Canon) {
3573      // We already have a "canonical" version of an identical, dependent
3574      // typeof(expr) type. Use that as our canonical type.
3575      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
3576                                          QualType((TypeOfExprType*)Canon, 0));
3577    } else {
3578      // Build a new, canonical typeof(expr) type.
3579      Canon
3580        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
3581      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
3582      toe = Canon;
3583    }
3584  } else {
3585    QualType Canonical = getCanonicalType(tofExpr->getType());
3586    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
3587  }
3588  Types.push_back(toe);
3589  return QualType(toe, 0);
3590}
3591
3592/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
3593/// TypeOfType AST's. The only motivation to unique these nodes would be
3594/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
3595/// an issue. This doesn't effect the type checker, since it operates
3596/// on canonical type's (which are always unique).
3597QualType ASTContext::getTypeOfType(QualType tofType) const {
3598  QualType Canonical = getCanonicalType(tofType);
3599  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
3600  Types.push_back(tot);
3601  return QualType(tot, 0);
3602}
3603
3604
3605/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
3606/// DecltypeType AST's. The only motivation to unique these nodes would be
3607/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
3608/// an issue. This doesn't effect the type checker, since it operates
3609/// on canonical types (which are always unique).
3610QualType ASTContext::getDecltypeType(Expr *e, QualType UnderlyingType) const {
3611  DecltypeType *dt;
3612
3613  // C++0x [temp.type]p2:
3614  //   If an expression e involves a template parameter, decltype(e) denotes a
3615  //   unique dependent type. Two such decltype-specifiers refer to the same
3616  //   type only if their expressions are equivalent (14.5.6.1).
3617  if (e->isInstantiationDependent()) {
3618    llvm::FoldingSetNodeID ID;
3619    DependentDecltypeType::Profile(ID, *this, e);
3620
3621    void *InsertPos = 0;
3622    DependentDecltypeType *Canon
3623      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
3624    if (Canon) {
3625      // We already have a "canonical" version of an equivalent, dependent
3626      // decltype type. Use that as our canonical type.
3627      dt = new (*this, TypeAlignment) DecltypeType(e, UnderlyingType,
3628                                       QualType((DecltypeType*)Canon, 0));
3629    } else {
3630      // Build a new, canonical typeof(expr) type.
3631      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
3632      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
3633      dt = Canon;
3634    }
3635  } else {
3636    dt = new (*this, TypeAlignment) DecltypeType(e, UnderlyingType,
3637                                      getCanonicalType(UnderlyingType));
3638  }
3639  Types.push_back(dt);
3640  return QualType(dt, 0);
3641}
3642
3643/// getUnaryTransformationType - We don't unique these, since the memory
3644/// savings are minimal and these are rare.
3645QualType ASTContext::getUnaryTransformType(QualType BaseType,
3646                                           QualType UnderlyingType,
3647                                           UnaryTransformType::UTTKind Kind)
3648    const {
3649  UnaryTransformType *Ty =
3650    new (*this, TypeAlignment) UnaryTransformType (BaseType, UnderlyingType,
3651                                                   Kind,
3652                                 UnderlyingType->isDependentType() ?
3653                                 QualType() : getCanonicalType(UnderlyingType));
3654  Types.push_back(Ty);
3655  return QualType(Ty, 0);
3656}
3657
3658/// getAutoType - Return the uniqued reference to the 'auto' type which has been
3659/// deduced to the given type, or to the canonical undeduced 'auto' type, or the
3660/// canonical deduced-but-dependent 'auto' type.
3661QualType ASTContext::getAutoType(QualType DeducedType, bool IsDecltypeAuto,
3662                                 bool IsDependent) const {
3663  if (DeducedType.isNull() && !IsDecltypeAuto && !IsDependent)
3664    return getAutoDeductType();
3665
3666  // Look in the folding set for an existing type.
3667  void *InsertPos = 0;
3668  llvm::FoldingSetNodeID ID;
3669  AutoType::Profile(ID, DeducedType, IsDecltypeAuto, IsDependent);
3670  if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
3671    return QualType(AT, 0);
3672
3673  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType,
3674                                                     IsDecltypeAuto,
3675                                                     IsDependent);
3676  Types.push_back(AT);
3677  if (InsertPos)
3678    AutoTypes.InsertNode(AT, InsertPos);
3679  return QualType(AT, 0);
3680}
3681
3682/// getAtomicType - Return the uniqued reference to the atomic type for
3683/// the given value type.
3684QualType ASTContext::getAtomicType(QualType T) const {
3685  // Unique pointers, to guarantee there is only one pointer of a particular
3686  // structure.
3687  llvm::FoldingSetNodeID ID;
3688  AtomicType::Profile(ID, T);
3689
3690  void *InsertPos = 0;
3691  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
3692    return QualType(AT, 0);
3693
3694  // If the atomic value type isn't canonical, this won't be a canonical type
3695  // either, so fill in the canonical type field.
3696  QualType Canonical;
3697  if (!T.isCanonical()) {
3698    Canonical = getAtomicType(getCanonicalType(T));
3699
3700    // Get the new insert position for the node we care about.
3701    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
3702    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
3703  }
3704  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
3705  Types.push_back(New);
3706  AtomicTypes.InsertNode(New, InsertPos);
3707  return QualType(New, 0);
3708}
3709
3710/// getAutoDeductType - Get type pattern for deducing against 'auto'.
3711QualType ASTContext::getAutoDeductType() const {
3712  if (AutoDeductTy.isNull())
3713    AutoDeductTy = QualType(
3714      new (*this, TypeAlignment) AutoType(QualType(), /*decltype(auto)*/false,
3715                                          /*dependent*/false),
3716      0);
3717  return AutoDeductTy;
3718}
3719
3720/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
3721QualType ASTContext::getAutoRRefDeductType() const {
3722  if (AutoRRefDeductTy.isNull())
3723    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
3724  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
3725  return AutoRRefDeductTy;
3726}
3727
3728/// getTagDeclType - Return the unique reference to the type for the
3729/// specified TagDecl (struct/union/class/enum) decl.
3730QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
3731  assert (Decl);
3732  // FIXME: What is the design on getTagDeclType when it requires casting
3733  // away const?  mutable?
3734  return getTypeDeclType(const_cast<TagDecl*>(Decl));
3735}
3736
3737/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
3738/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
3739/// needs to agree with the definition in <stddef.h>.
3740CanQualType ASTContext::getSizeType() const {
3741  return getFromTargetType(Target->getSizeType());
3742}
3743
3744/// getIntMaxType - Return the unique type for "intmax_t" (C99 7.18.1.5).
3745CanQualType ASTContext::getIntMaxType() const {
3746  return getFromTargetType(Target->getIntMaxType());
3747}
3748
3749/// getUIntMaxType - Return the unique type for "uintmax_t" (C99 7.18.1.5).
3750CanQualType ASTContext::getUIntMaxType() const {
3751  return getFromTargetType(Target->getUIntMaxType());
3752}
3753
3754/// getSignedWCharType - Return the type of "signed wchar_t".
3755/// Used when in C++, as a GCC extension.
3756QualType ASTContext::getSignedWCharType() const {
3757  // FIXME: derive from "Target" ?
3758  return WCharTy;
3759}
3760
3761/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
3762/// Used when in C++, as a GCC extension.
3763QualType ASTContext::getUnsignedWCharType() const {
3764  // FIXME: derive from "Target" ?
3765  return UnsignedIntTy;
3766}
3767
3768QualType ASTContext::getIntPtrType() const {
3769  return getFromTargetType(Target->getIntPtrType());
3770}
3771
3772QualType ASTContext::getUIntPtrType() const {
3773  return getCorrespondingUnsignedType(getIntPtrType());
3774}
3775
3776/// getPointerDiffType - Return the unique type for "ptrdiff_t" (C99 7.17)
3777/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
3778QualType ASTContext::getPointerDiffType() const {
3779  return getFromTargetType(Target->getPtrDiffType(0));
3780}
3781
3782/// \brief Return the unique type for "pid_t" defined in
3783/// <sys/types.h>. We need this to compute the correct type for vfork().
3784QualType ASTContext::getProcessIDType() const {
3785  return getFromTargetType(Target->getProcessIDType());
3786}
3787
3788//===----------------------------------------------------------------------===//
3789//                              Type Operators
3790//===----------------------------------------------------------------------===//
3791
3792CanQualType ASTContext::getCanonicalParamType(QualType T) const {
3793  // Push qualifiers into arrays, and then discard any remaining
3794  // qualifiers.
3795  T = getCanonicalType(T);
3796  T = getVariableArrayDecayedType(T);
3797  const Type *Ty = T.getTypePtr();
3798  QualType Result;
3799  if (isa<ArrayType>(Ty)) {
3800    Result = getArrayDecayedType(QualType(Ty,0));
3801  } else if (isa<FunctionType>(Ty)) {
3802    Result = getPointerType(QualType(Ty, 0));
3803  } else {
3804    Result = QualType(Ty, 0);
3805  }
3806
3807  return CanQualType::CreateUnsafe(Result);
3808}
3809
3810QualType ASTContext::getUnqualifiedArrayType(QualType type,
3811                                             Qualifiers &quals) {
3812  SplitQualType splitType = type.getSplitUnqualifiedType();
3813
3814  // FIXME: getSplitUnqualifiedType() actually walks all the way to
3815  // the unqualified desugared type and then drops it on the floor.
3816  // We then have to strip that sugar back off with
3817  // getUnqualifiedDesugaredType(), which is silly.
3818  const ArrayType *AT =
3819    dyn_cast<ArrayType>(splitType.Ty->getUnqualifiedDesugaredType());
3820
3821  // If we don't have an array, just use the results in splitType.
3822  if (!AT) {
3823    quals = splitType.Quals;
3824    return QualType(splitType.Ty, 0);
3825  }
3826
3827  // Otherwise, recurse on the array's element type.
3828  QualType elementType = AT->getElementType();
3829  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
3830
3831  // If that didn't change the element type, AT has no qualifiers, so we
3832  // can just use the results in splitType.
3833  if (elementType == unqualElementType) {
3834    assert(quals.empty()); // from the recursive call
3835    quals = splitType.Quals;
3836    return QualType(splitType.Ty, 0);
3837  }
3838
3839  // Otherwise, add in the qualifiers from the outermost type, then
3840  // build the type back up.
3841  quals.addConsistentQualifiers(splitType.Quals);
3842
3843  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
3844    return getConstantArrayType(unqualElementType, CAT->getSize(),
3845                                CAT->getSizeModifier(), 0);
3846  }
3847
3848  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
3849    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
3850  }
3851
3852  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
3853    return getVariableArrayType(unqualElementType,
3854                                VAT->getSizeExpr(),
3855                                VAT->getSizeModifier(),
3856                                VAT->getIndexTypeCVRQualifiers(),
3857                                VAT->getBracketsRange());
3858  }
3859
3860  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
3861  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
3862                                    DSAT->getSizeModifier(), 0,
3863                                    SourceRange());
3864}
3865
3866/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
3867/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
3868/// they point to and return true. If T1 and T2 aren't pointer types
3869/// or pointer-to-member types, or if they are not similar at this
3870/// level, returns false and leaves T1 and T2 unchanged. Top-level
3871/// qualifiers on T1 and T2 are ignored. This function will typically
3872/// be called in a loop that successively "unwraps" pointer and
3873/// pointer-to-member types to compare them at each level.
3874bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
3875  const PointerType *T1PtrType = T1->getAs<PointerType>(),
3876                    *T2PtrType = T2->getAs<PointerType>();
3877  if (T1PtrType && T2PtrType) {
3878    T1 = T1PtrType->getPointeeType();
3879    T2 = T2PtrType->getPointeeType();
3880    return true;
3881  }
3882
3883  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
3884                          *T2MPType = T2->getAs<MemberPointerType>();
3885  if (T1MPType && T2MPType &&
3886      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
3887                             QualType(T2MPType->getClass(), 0))) {
3888    T1 = T1MPType->getPointeeType();
3889    T2 = T2MPType->getPointeeType();
3890    return true;
3891  }
3892
3893  if (getLangOpts().ObjC1) {
3894    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
3895                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
3896    if (T1OPType && T2OPType) {
3897      T1 = T1OPType->getPointeeType();
3898      T2 = T2OPType->getPointeeType();
3899      return true;
3900    }
3901  }
3902
3903  // FIXME: Block pointers, too?
3904
3905  return false;
3906}
3907
3908DeclarationNameInfo
3909ASTContext::getNameForTemplate(TemplateName Name,
3910                               SourceLocation NameLoc) const {
3911  switch (Name.getKind()) {
3912  case TemplateName::QualifiedTemplate:
3913  case TemplateName::Template:
3914    // DNInfo work in progress: CHECKME: what about DNLoc?
3915    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
3916                               NameLoc);
3917
3918  case TemplateName::OverloadedTemplate: {
3919    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
3920    // DNInfo work in progress: CHECKME: what about DNLoc?
3921    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
3922  }
3923
3924  case TemplateName::DependentTemplate: {
3925    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3926    DeclarationName DName;
3927    if (DTN->isIdentifier()) {
3928      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
3929      return DeclarationNameInfo(DName, NameLoc);
3930    } else {
3931      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
3932      // DNInfo work in progress: FIXME: source locations?
3933      DeclarationNameLoc DNLoc;
3934      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
3935      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
3936      return DeclarationNameInfo(DName, NameLoc, DNLoc);
3937    }
3938  }
3939
3940  case TemplateName::SubstTemplateTemplateParm: {
3941    SubstTemplateTemplateParmStorage *subst
3942      = Name.getAsSubstTemplateTemplateParm();
3943    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
3944                               NameLoc);
3945  }
3946
3947  case TemplateName::SubstTemplateTemplateParmPack: {
3948    SubstTemplateTemplateParmPackStorage *subst
3949      = Name.getAsSubstTemplateTemplateParmPack();
3950    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
3951                               NameLoc);
3952  }
3953  }
3954
3955  llvm_unreachable("bad template name kind!");
3956}
3957
3958TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
3959  switch (Name.getKind()) {
3960  case TemplateName::QualifiedTemplate:
3961  case TemplateName::Template: {
3962    TemplateDecl *Template = Name.getAsTemplateDecl();
3963    if (TemplateTemplateParmDecl *TTP
3964          = dyn_cast<TemplateTemplateParmDecl>(Template))
3965      Template = getCanonicalTemplateTemplateParmDecl(TTP);
3966
3967    // The canonical template name is the canonical template declaration.
3968    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
3969  }
3970
3971  case TemplateName::OverloadedTemplate:
3972    llvm_unreachable("cannot canonicalize overloaded template");
3973
3974  case TemplateName::DependentTemplate: {
3975    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3976    assert(DTN && "Non-dependent template names must refer to template decls.");
3977    return DTN->CanonicalTemplateName;
3978  }
3979
3980  case TemplateName::SubstTemplateTemplateParm: {
3981    SubstTemplateTemplateParmStorage *subst
3982      = Name.getAsSubstTemplateTemplateParm();
3983    return getCanonicalTemplateName(subst->getReplacement());
3984  }
3985
3986  case TemplateName::SubstTemplateTemplateParmPack: {
3987    SubstTemplateTemplateParmPackStorage *subst
3988                                  = Name.getAsSubstTemplateTemplateParmPack();
3989    TemplateTemplateParmDecl *canonParameter
3990      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
3991    TemplateArgument canonArgPack
3992      = getCanonicalTemplateArgument(subst->getArgumentPack());
3993    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
3994  }
3995  }
3996
3997  llvm_unreachable("bad template name!");
3998}
3999
4000bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
4001  X = getCanonicalTemplateName(X);
4002  Y = getCanonicalTemplateName(Y);
4003  return X.getAsVoidPointer() == Y.getAsVoidPointer();
4004}
4005
4006TemplateArgument
4007ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
4008  switch (Arg.getKind()) {
4009    case TemplateArgument::Null:
4010      return Arg;
4011
4012    case TemplateArgument::Expression:
4013      return Arg;
4014
4015    case TemplateArgument::Declaration: {
4016      ValueDecl *D = cast<ValueDecl>(Arg.getAsDecl()->getCanonicalDecl());
4017      return TemplateArgument(D, Arg.isDeclForReferenceParam());
4018    }
4019
4020    case TemplateArgument::NullPtr:
4021      return TemplateArgument(getCanonicalType(Arg.getNullPtrType()),
4022                              /*isNullPtr*/true);
4023
4024    case TemplateArgument::Template:
4025      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
4026
4027    case TemplateArgument::TemplateExpansion:
4028      return TemplateArgument(getCanonicalTemplateName(
4029                                         Arg.getAsTemplateOrTemplatePattern()),
4030                              Arg.getNumTemplateExpansions());
4031
4032    case TemplateArgument::Integral:
4033      return TemplateArgument(Arg, getCanonicalType(Arg.getIntegralType()));
4034
4035    case TemplateArgument::Type:
4036      return TemplateArgument(getCanonicalType(Arg.getAsType()));
4037
4038    case TemplateArgument::Pack: {
4039      if (Arg.pack_size() == 0)
4040        return Arg;
4041
4042      TemplateArgument *CanonArgs
4043        = new (*this) TemplateArgument[Arg.pack_size()];
4044      unsigned Idx = 0;
4045      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
4046                                        AEnd = Arg.pack_end();
4047           A != AEnd; (void)++A, ++Idx)
4048        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
4049
4050      return TemplateArgument(CanonArgs, Arg.pack_size());
4051    }
4052  }
4053
4054  // Silence GCC warning
4055  llvm_unreachable("Unhandled template argument kind");
4056}
4057
4058NestedNameSpecifier *
4059ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
4060  if (!NNS)
4061    return 0;
4062
4063  switch (NNS->getKind()) {
4064  case NestedNameSpecifier::Identifier:
4065    // Canonicalize the prefix but keep the identifier the same.
4066    return NestedNameSpecifier::Create(*this,
4067                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
4068                                       NNS->getAsIdentifier());
4069
4070  case NestedNameSpecifier::Namespace:
4071    // A namespace is canonical; build a nested-name-specifier with
4072    // this namespace and no prefix.
4073    return NestedNameSpecifier::Create(*this, 0,
4074                                 NNS->getAsNamespace()->getOriginalNamespace());
4075
4076  case NestedNameSpecifier::NamespaceAlias:
4077    // A namespace is canonical; build a nested-name-specifier with
4078    // this namespace and no prefix.
4079    return NestedNameSpecifier::Create(*this, 0,
4080                                    NNS->getAsNamespaceAlias()->getNamespace()
4081                                                      ->getOriginalNamespace());
4082
4083  case NestedNameSpecifier::TypeSpec:
4084  case NestedNameSpecifier::TypeSpecWithTemplate: {
4085    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
4086
4087    // If we have some kind of dependent-named type (e.g., "typename T::type"),
4088    // break it apart into its prefix and identifier, then reconsititute those
4089    // as the canonical nested-name-specifier. This is required to canonicalize
4090    // a dependent nested-name-specifier involving typedefs of dependent-name
4091    // types, e.g.,
4092    //   typedef typename T::type T1;
4093    //   typedef typename T1::type T2;
4094    if (const DependentNameType *DNT = T->getAs<DependentNameType>())
4095      return NestedNameSpecifier::Create(*this, DNT->getQualifier(),
4096                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
4097
4098    // Otherwise, just canonicalize the type, and force it to be a TypeSpec.
4099    // FIXME: Why are TypeSpec and TypeSpecWithTemplate distinct in the
4100    // first place?
4101    return NestedNameSpecifier::Create(*this, 0, false,
4102                                       const_cast<Type*>(T.getTypePtr()));
4103  }
4104
4105  case NestedNameSpecifier::Global:
4106    // The global specifier is canonical and unique.
4107    return NNS;
4108  }
4109
4110  llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
4111}
4112
4113
4114const ArrayType *ASTContext::getAsArrayType(QualType T) const {
4115  // Handle the non-qualified case efficiently.
4116  if (!T.hasLocalQualifiers()) {
4117    // Handle the common positive case fast.
4118    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
4119      return AT;
4120  }
4121
4122  // Handle the common negative case fast.
4123  if (!isa<ArrayType>(T.getCanonicalType()))
4124    return 0;
4125
4126  // Apply any qualifiers from the array type to the element type.  This
4127  // implements C99 6.7.3p8: "If the specification of an array type includes
4128  // any type qualifiers, the element type is so qualified, not the array type."
4129
4130  // If we get here, we either have type qualifiers on the type, or we have
4131  // sugar such as a typedef in the way.  If we have type qualifiers on the type
4132  // we must propagate them down into the element type.
4133
4134  SplitQualType split = T.getSplitDesugaredType();
4135  Qualifiers qs = split.Quals;
4136
4137  // If we have a simple case, just return now.
4138  const ArrayType *ATy = dyn_cast<ArrayType>(split.Ty);
4139  if (ATy == 0 || qs.empty())
4140    return ATy;
4141
4142  // Otherwise, we have an array and we have qualifiers on it.  Push the
4143  // qualifiers into the array element type and return a new array type.
4144  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
4145
4146  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
4147    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
4148                                                CAT->getSizeModifier(),
4149                                           CAT->getIndexTypeCVRQualifiers()));
4150  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
4151    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
4152                                                  IAT->getSizeModifier(),
4153                                           IAT->getIndexTypeCVRQualifiers()));
4154
4155  if (const DependentSizedArrayType *DSAT
4156        = dyn_cast<DependentSizedArrayType>(ATy))
4157    return cast<ArrayType>(
4158                     getDependentSizedArrayType(NewEltTy,
4159                                                DSAT->getSizeExpr(),
4160                                                DSAT->getSizeModifier(),
4161                                              DSAT->getIndexTypeCVRQualifiers(),
4162                                                DSAT->getBracketsRange()));
4163
4164  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
4165  return cast<ArrayType>(getVariableArrayType(NewEltTy,
4166                                              VAT->getSizeExpr(),
4167                                              VAT->getSizeModifier(),
4168                                              VAT->getIndexTypeCVRQualifiers(),
4169                                              VAT->getBracketsRange()));
4170}
4171
4172QualType ASTContext::getAdjustedParameterType(QualType T) const {
4173  if (T->isArrayType() || T->isFunctionType())
4174    return getDecayedType(T);
4175  return T;
4176}
4177
4178QualType ASTContext::getSignatureParameterType(QualType T) const {
4179  T = getVariableArrayDecayedType(T);
4180  T = getAdjustedParameterType(T);
4181  return T.getUnqualifiedType();
4182}
4183
4184/// getArrayDecayedType - Return the properly qualified result of decaying the
4185/// specified array type to a pointer.  This operation is non-trivial when
4186/// handling typedefs etc.  The canonical type of "T" must be an array type,
4187/// this returns a pointer to a properly qualified element of the array.
4188///
4189/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
4190QualType ASTContext::getArrayDecayedType(QualType Ty) const {
4191  // Get the element type with 'getAsArrayType' so that we don't lose any
4192  // typedefs in the element type of the array.  This also handles propagation
4193  // of type qualifiers from the array type into the element type if present
4194  // (C99 6.7.3p8).
4195  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
4196  assert(PrettyArrayType && "Not an array type!");
4197
4198  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
4199
4200  // int x[restrict 4] ->  int *restrict
4201  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
4202}
4203
4204QualType ASTContext::getBaseElementType(const ArrayType *array) const {
4205  return getBaseElementType(array->getElementType());
4206}
4207
4208QualType ASTContext::getBaseElementType(QualType type) const {
4209  Qualifiers qs;
4210  while (true) {
4211    SplitQualType split = type.getSplitDesugaredType();
4212    const ArrayType *array = split.Ty->getAsArrayTypeUnsafe();
4213    if (!array) break;
4214
4215    type = array->getElementType();
4216    qs.addConsistentQualifiers(split.Quals);
4217  }
4218
4219  return getQualifiedType(type, qs);
4220}
4221
4222/// getConstantArrayElementCount - Returns number of constant array elements.
4223uint64_t
4224ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
4225  uint64_t ElementCount = 1;
4226  do {
4227    ElementCount *= CA->getSize().getZExtValue();
4228    CA = dyn_cast_or_null<ConstantArrayType>(
4229      CA->getElementType()->getAsArrayTypeUnsafe());
4230  } while (CA);
4231  return ElementCount;
4232}
4233
4234/// getFloatingRank - Return a relative rank for floating point types.
4235/// This routine will assert if passed a built-in type that isn't a float.
4236static FloatingRank getFloatingRank(QualType T) {
4237  if (const ComplexType *CT = T->getAs<ComplexType>())
4238    return getFloatingRank(CT->getElementType());
4239
4240  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
4241  switch (T->getAs<BuiltinType>()->getKind()) {
4242  default: llvm_unreachable("getFloatingRank(): not a floating type");
4243  case BuiltinType::Half:       return HalfRank;
4244  case BuiltinType::Float:      return FloatRank;
4245  case BuiltinType::Double:     return DoubleRank;
4246  case BuiltinType::LongDouble: return LongDoubleRank;
4247  }
4248}
4249
4250/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
4251/// point or a complex type (based on typeDomain/typeSize).
4252/// 'typeDomain' is a real floating point or complex type.
4253/// 'typeSize' is a real floating point or complex type.
4254QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
4255                                                       QualType Domain) const {
4256  FloatingRank EltRank = getFloatingRank(Size);
4257  if (Domain->isComplexType()) {
4258    switch (EltRank) {
4259    case HalfRank: llvm_unreachable("Complex half is not supported");
4260    case FloatRank:      return FloatComplexTy;
4261    case DoubleRank:     return DoubleComplexTy;
4262    case LongDoubleRank: return LongDoubleComplexTy;
4263    }
4264  }
4265
4266  assert(Domain->isRealFloatingType() && "Unknown domain!");
4267  switch (EltRank) {
4268  case HalfRank:       return HalfTy;
4269  case FloatRank:      return FloatTy;
4270  case DoubleRank:     return DoubleTy;
4271  case LongDoubleRank: return LongDoubleTy;
4272  }
4273  llvm_unreachable("getFloatingRank(): illegal value for rank");
4274}
4275
4276/// getFloatingTypeOrder - Compare the rank of the two specified floating
4277/// point types, ignoring the domain of the type (i.e. 'double' ==
4278/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
4279/// LHS < RHS, return -1.
4280int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
4281  FloatingRank LHSR = getFloatingRank(LHS);
4282  FloatingRank RHSR = getFloatingRank(RHS);
4283
4284  if (LHSR == RHSR)
4285    return 0;
4286  if (LHSR > RHSR)
4287    return 1;
4288  return -1;
4289}
4290
4291/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
4292/// routine will assert if passed a built-in type that isn't an integer or enum,
4293/// or if it is not canonicalized.
4294unsigned ASTContext::getIntegerRank(const Type *T) const {
4295  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
4296
4297  switch (cast<BuiltinType>(T)->getKind()) {
4298  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
4299  case BuiltinType::Bool:
4300    return 1 + (getIntWidth(BoolTy) << 3);
4301  case BuiltinType::Char_S:
4302  case BuiltinType::Char_U:
4303  case BuiltinType::SChar:
4304  case BuiltinType::UChar:
4305    return 2 + (getIntWidth(CharTy) << 3);
4306  case BuiltinType::Short:
4307  case BuiltinType::UShort:
4308    return 3 + (getIntWidth(ShortTy) << 3);
4309  case BuiltinType::Int:
4310  case BuiltinType::UInt:
4311    return 4 + (getIntWidth(IntTy) << 3);
4312  case BuiltinType::Long:
4313  case BuiltinType::ULong:
4314    return 5 + (getIntWidth(LongTy) << 3);
4315  case BuiltinType::LongLong:
4316  case BuiltinType::ULongLong:
4317    return 6 + (getIntWidth(LongLongTy) << 3);
4318  case BuiltinType::Int128:
4319  case BuiltinType::UInt128:
4320    return 7 + (getIntWidth(Int128Ty) << 3);
4321  }
4322}
4323
4324/// \brief Whether this is a promotable bitfield reference according
4325/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
4326///
4327/// \returns the type this bit-field will promote to, or NULL if no
4328/// promotion occurs.
4329QualType ASTContext::isPromotableBitField(Expr *E) const {
4330  if (E->isTypeDependent() || E->isValueDependent())
4331    return QualType();
4332
4333  FieldDecl *Field = E->getSourceBitField(); // FIXME: conditional bit-fields?
4334  if (!Field)
4335    return QualType();
4336
4337  QualType FT = Field->getType();
4338
4339  uint64_t BitWidth = Field->getBitWidthValue(*this);
4340  uint64_t IntSize = getTypeSize(IntTy);
4341  // GCC extension compatibility: if the bit-field size is less than or equal
4342  // to the size of int, it gets promoted no matter what its type is.
4343  // For instance, unsigned long bf : 4 gets promoted to signed int.
4344  if (BitWidth < IntSize)
4345    return IntTy;
4346
4347  if (BitWidth == IntSize)
4348    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
4349
4350  // Types bigger than int are not subject to promotions, and therefore act
4351  // like the base type.
4352  // FIXME: This doesn't quite match what gcc does, but what gcc does here
4353  // is ridiculous.
4354  return QualType();
4355}
4356
4357/// getPromotedIntegerType - Returns the type that Promotable will
4358/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
4359/// integer type.
4360QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
4361  assert(!Promotable.isNull());
4362  assert(Promotable->isPromotableIntegerType());
4363  if (const EnumType *ET = Promotable->getAs<EnumType>())
4364    return ET->getDecl()->getPromotionType();
4365
4366  if (const BuiltinType *BT = Promotable->getAs<BuiltinType>()) {
4367    // C++ [conv.prom]: A prvalue of type char16_t, char32_t, or wchar_t
4368    // (3.9.1) can be converted to a prvalue of the first of the following
4369    // types that can represent all the values of its underlying type:
4370    // int, unsigned int, long int, unsigned long int, long long int, or
4371    // unsigned long long int [...]
4372    // FIXME: Is there some better way to compute this?
4373    if (BT->getKind() == BuiltinType::WChar_S ||
4374        BT->getKind() == BuiltinType::WChar_U ||
4375        BT->getKind() == BuiltinType::Char16 ||
4376        BT->getKind() == BuiltinType::Char32) {
4377      bool FromIsSigned = BT->getKind() == BuiltinType::WChar_S;
4378      uint64_t FromSize = getTypeSize(BT);
4379      QualType PromoteTypes[] = { IntTy, UnsignedIntTy, LongTy, UnsignedLongTy,
4380                                  LongLongTy, UnsignedLongLongTy };
4381      for (size_t Idx = 0; Idx < llvm::array_lengthof(PromoteTypes); ++Idx) {
4382        uint64_t ToSize = getTypeSize(PromoteTypes[Idx]);
4383        if (FromSize < ToSize ||
4384            (FromSize == ToSize &&
4385             FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType()))
4386          return PromoteTypes[Idx];
4387      }
4388      llvm_unreachable("char type should fit into long long");
4389    }
4390  }
4391
4392  // At this point, we should have a signed or unsigned integer type.
4393  if (Promotable->isSignedIntegerType())
4394    return IntTy;
4395  uint64_t PromotableSize = getIntWidth(Promotable);
4396  uint64_t IntSize = getIntWidth(IntTy);
4397  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
4398  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
4399}
4400
4401/// \brief Recurses in pointer/array types until it finds an objc retainable
4402/// type and returns its ownership.
4403Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
4404  while (!T.isNull()) {
4405    if (T.getObjCLifetime() != Qualifiers::OCL_None)
4406      return T.getObjCLifetime();
4407    if (T->isArrayType())
4408      T = getBaseElementType(T);
4409    else if (const PointerType *PT = T->getAs<PointerType>())
4410      T = PT->getPointeeType();
4411    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4412      T = RT->getPointeeType();
4413    else
4414      break;
4415  }
4416
4417  return Qualifiers::OCL_None;
4418}
4419
4420/// getIntegerTypeOrder - Returns the highest ranked integer type:
4421/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
4422/// LHS < RHS, return -1.
4423int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
4424  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
4425  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
4426  if (LHSC == RHSC) return 0;
4427
4428  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
4429  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
4430
4431  unsigned LHSRank = getIntegerRank(LHSC);
4432  unsigned RHSRank = getIntegerRank(RHSC);
4433
4434  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
4435    if (LHSRank == RHSRank) return 0;
4436    return LHSRank > RHSRank ? 1 : -1;
4437  }
4438
4439  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
4440  if (LHSUnsigned) {
4441    // If the unsigned [LHS] type is larger, return it.
4442    if (LHSRank >= RHSRank)
4443      return 1;
4444
4445    // If the signed type can represent all values of the unsigned type, it
4446    // wins.  Because we are dealing with 2's complement and types that are
4447    // powers of two larger than each other, this is always safe.
4448    return -1;
4449  }
4450
4451  // If the unsigned [RHS] type is larger, return it.
4452  if (RHSRank >= LHSRank)
4453    return -1;
4454
4455  // If the signed type can represent all values of the unsigned type, it
4456  // wins.  Because we are dealing with 2's complement and types that are
4457  // powers of two larger than each other, this is always safe.
4458  return 1;
4459}
4460
4461static RecordDecl *
4462CreateRecordDecl(const ASTContext &Ctx, RecordDecl::TagKind TK,
4463                 DeclContext *DC, IdentifierInfo *Id) {
4464  SourceLocation Loc;
4465  if (Ctx.getLangOpts().CPlusPlus)
4466    return CXXRecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
4467  else
4468    return RecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
4469}
4470
4471// getCFConstantStringType - Return the type used for constant CFStrings.
4472QualType ASTContext::getCFConstantStringType() const {
4473  if (!CFConstantStringTypeDecl) {
4474    CFConstantStringTypeDecl =
4475      CreateRecordDecl(*this, TTK_Struct, TUDecl,
4476                       &Idents.get("NSConstantString"));
4477    CFConstantStringTypeDecl->startDefinition();
4478
4479    QualType FieldTypes[4];
4480
4481    // const int *isa;
4482    FieldTypes[0] = getPointerType(IntTy.withConst());
4483    // int flags;
4484    FieldTypes[1] = IntTy;
4485    // const char *str;
4486    FieldTypes[2] = getPointerType(CharTy.withConst());
4487    // long length;
4488    FieldTypes[3] = LongTy;
4489
4490    // Create fields
4491    for (unsigned i = 0; i < 4; ++i) {
4492      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
4493                                           SourceLocation(),
4494                                           SourceLocation(), 0,
4495                                           FieldTypes[i], /*TInfo=*/0,
4496                                           /*BitWidth=*/0,
4497                                           /*Mutable=*/false,
4498                                           ICIS_NoInit);
4499      Field->setAccess(AS_public);
4500      CFConstantStringTypeDecl->addDecl(Field);
4501    }
4502
4503    CFConstantStringTypeDecl->completeDefinition();
4504  }
4505
4506  return getTagDeclType(CFConstantStringTypeDecl);
4507}
4508
4509QualType ASTContext::getObjCSuperType() const {
4510  if (ObjCSuperType.isNull()) {
4511    RecordDecl *ObjCSuperTypeDecl  =
4512      CreateRecordDecl(*this, TTK_Struct, TUDecl, &Idents.get("objc_super"));
4513    TUDecl->addDecl(ObjCSuperTypeDecl);
4514    ObjCSuperType = getTagDeclType(ObjCSuperTypeDecl);
4515  }
4516  return ObjCSuperType;
4517}
4518
4519void ASTContext::setCFConstantStringType(QualType T) {
4520  const RecordType *Rec = T->getAs<RecordType>();
4521  assert(Rec && "Invalid CFConstantStringType");
4522  CFConstantStringTypeDecl = Rec->getDecl();
4523}
4524
4525QualType ASTContext::getBlockDescriptorType() const {
4526  if (BlockDescriptorType)
4527    return getTagDeclType(BlockDescriptorType);
4528
4529  RecordDecl *T;
4530  // FIXME: Needs the FlagAppleBlock bit.
4531  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
4532                       &Idents.get("__block_descriptor"));
4533  T->startDefinition();
4534
4535  QualType FieldTypes[] = {
4536    UnsignedLongTy,
4537    UnsignedLongTy,
4538  };
4539
4540  static const char *const FieldNames[] = {
4541    "reserved",
4542    "Size"
4543  };
4544
4545  for (size_t i = 0; i < 2; ++i) {
4546    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
4547                                         SourceLocation(),
4548                                         &Idents.get(FieldNames[i]),
4549                                         FieldTypes[i], /*TInfo=*/0,
4550                                         /*BitWidth=*/0,
4551                                         /*Mutable=*/false,
4552                                         ICIS_NoInit);
4553    Field->setAccess(AS_public);
4554    T->addDecl(Field);
4555  }
4556
4557  T->completeDefinition();
4558
4559  BlockDescriptorType = T;
4560
4561  return getTagDeclType(BlockDescriptorType);
4562}
4563
4564QualType ASTContext::getBlockDescriptorExtendedType() const {
4565  if (BlockDescriptorExtendedType)
4566    return getTagDeclType(BlockDescriptorExtendedType);
4567
4568  RecordDecl *T;
4569  // FIXME: Needs the FlagAppleBlock bit.
4570  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
4571                       &Idents.get("__block_descriptor_withcopydispose"));
4572  T->startDefinition();
4573
4574  QualType FieldTypes[] = {
4575    UnsignedLongTy,
4576    UnsignedLongTy,
4577    getPointerType(VoidPtrTy),
4578    getPointerType(VoidPtrTy)
4579  };
4580
4581  static const char *const FieldNames[] = {
4582    "reserved",
4583    "Size",
4584    "CopyFuncPtr",
4585    "DestroyFuncPtr"
4586  };
4587
4588  for (size_t i = 0; i < 4; ++i) {
4589    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
4590                                         SourceLocation(),
4591                                         &Idents.get(FieldNames[i]),
4592                                         FieldTypes[i], /*TInfo=*/0,
4593                                         /*BitWidth=*/0,
4594                                         /*Mutable=*/false,
4595                                         ICIS_NoInit);
4596    Field->setAccess(AS_public);
4597    T->addDecl(Field);
4598  }
4599
4600  T->completeDefinition();
4601
4602  BlockDescriptorExtendedType = T;
4603
4604  return getTagDeclType(BlockDescriptorExtendedType);
4605}
4606
4607/// BlockRequiresCopying - Returns true if byref variable "D" of type "Ty"
4608/// requires copy/dispose. Note that this must match the logic
4609/// in buildByrefHelpers.
4610bool ASTContext::BlockRequiresCopying(QualType Ty,
4611                                      const VarDecl *D) {
4612  if (const CXXRecordDecl *record = Ty->getAsCXXRecordDecl()) {
4613    const Expr *copyExpr = getBlockVarCopyInits(D);
4614    if (!copyExpr && record->hasTrivialDestructor()) return false;
4615
4616    return true;
4617  }
4618
4619  if (!Ty->isObjCRetainableType()) return false;
4620
4621  Qualifiers qs = Ty.getQualifiers();
4622
4623  // If we have lifetime, that dominates.
4624  if (Qualifiers::ObjCLifetime lifetime = qs.getObjCLifetime()) {
4625    assert(getLangOpts().ObjCAutoRefCount);
4626
4627    switch (lifetime) {
4628      case Qualifiers::OCL_None: llvm_unreachable("impossible");
4629
4630      // These are just bits as far as the runtime is concerned.
4631      case Qualifiers::OCL_ExplicitNone:
4632      case Qualifiers::OCL_Autoreleasing:
4633        return false;
4634
4635      // Tell the runtime that this is ARC __weak, called by the
4636      // byref routines.
4637      case Qualifiers::OCL_Weak:
4638      // ARC __strong __block variables need to be retained.
4639      case Qualifiers::OCL_Strong:
4640        return true;
4641    }
4642    llvm_unreachable("fell out of lifetime switch!");
4643  }
4644  return (Ty->isBlockPointerType() || isObjCNSObjectType(Ty) ||
4645          Ty->isObjCObjectPointerType());
4646}
4647
4648bool ASTContext::getByrefLifetime(QualType Ty,
4649                              Qualifiers::ObjCLifetime &LifeTime,
4650                              bool &HasByrefExtendedLayout) const {
4651
4652  if (!getLangOpts().ObjC1 ||
4653      getLangOpts().getGC() != LangOptions::NonGC)
4654    return false;
4655
4656  HasByrefExtendedLayout = false;
4657  if (Ty->isRecordType()) {
4658    HasByrefExtendedLayout = true;
4659    LifeTime = Qualifiers::OCL_None;
4660  }
4661  else if (getLangOpts().ObjCAutoRefCount)
4662    LifeTime = Ty.getObjCLifetime();
4663  // MRR.
4664  else if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4665    LifeTime = Qualifiers::OCL_ExplicitNone;
4666  else
4667    LifeTime = Qualifiers::OCL_None;
4668  return true;
4669}
4670
4671TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
4672  if (!ObjCInstanceTypeDecl)
4673    ObjCInstanceTypeDecl = TypedefDecl::Create(*this,
4674                                               getTranslationUnitDecl(),
4675                                               SourceLocation(),
4676                                               SourceLocation(),
4677                                               &Idents.get("instancetype"),
4678                                     getTrivialTypeSourceInfo(getObjCIdType()));
4679  return ObjCInstanceTypeDecl;
4680}
4681
4682// This returns true if a type has been typedefed to BOOL:
4683// typedef <type> BOOL;
4684static bool isTypeTypedefedAsBOOL(QualType T) {
4685  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
4686    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
4687      return II->isStr("BOOL");
4688
4689  return false;
4690}
4691
4692/// getObjCEncodingTypeSize returns size of type for objective-c encoding
4693/// purpose.
4694CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
4695  if (!type->isIncompleteArrayType() && type->isIncompleteType())
4696    return CharUnits::Zero();
4697
4698  CharUnits sz = getTypeSizeInChars(type);
4699
4700  // Make all integer and enum types at least as large as an int
4701  if (sz.isPositive() && type->isIntegralOrEnumerationType())
4702    sz = std::max(sz, getTypeSizeInChars(IntTy));
4703  // Treat arrays as pointers, since that's how they're passed in.
4704  else if (type->isArrayType())
4705    sz = getTypeSizeInChars(VoidPtrTy);
4706  return sz;
4707}
4708
4709static inline
4710std::string charUnitsToString(const CharUnits &CU) {
4711  return llvm::itostr(CU.getQuantity());
4712}
4713
4714/// getObjCEncodingForBlock - Return the encoded type for this block
4715/// declaration.
4716std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
4717  std::string S;
4718
4719  const BlockDecl *Decl = Expr->getBlockDecl();
4720  QualType BlockTy =
4721      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
4722  // Encode result type.
4723  if (getLangOpts().EncodeExtendedBlockSig)
4724    getObjCEncodingForMethodParameter(Decl::OBJC_TQ_None,
4725                            BlockTy->getAs<FunctionType>()->getResultType(),
4726                            S, true /*Extended*/);
4727  else
4728    getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(),
4729                           S);
4730  // Compute size of all parameters.
4731  // Start with computing size of a pointer in number of bytes.
4732  // FIXME: There might(should) be a better way of doing this computation!
4733  SourceLocation Loc;
4734  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4735  CharUnits ParmOffset = PtrSize;
4736  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
4737       E = Decl->param_end(); PI != E; ++PI) {
4738    QualType PType = (*PI)->getType();
4739    CharUnits sz = getObjCEncodingTypeSize(PType);
4740    if (sz.isZero())
4741      continue;
4742    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
4743    ParmOffset += sz;
4744  }
4745  // Size of the argument frame
4746  S += charUnitsToString(ParmOffset);
4747  // Block pointer and offset.
4748  S += "@?0";
4749
4750  // Argument types.
4751  ParmOffset = PtrSize;
4752  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
4753       Decl->param_end(); PI != E; ++PI) {
4754    ParmVarDecl *PVDecl = *PI;
4755    QualType PType = PVDecl->getOriginalType();
4756    if (const ArrayType *AT =
4757          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4758      // Use array's original type only if it has known number of
4759      // elements.
4760      if (!isa<ConstantArrayType>(AT))
4761        PType = PVDecl->getType();
4762    } else if (PType->isFunctionType())
4763      PType = PVDecl->getType();
4764    if (getLangOpts().EncodeExtendedBlockSig)
4765      getObjCEncodingForMethodParameter(Decl::OBJC_TQ_None, PType,
4766                                      S, true /*Extended*/);
4767    else
4768      getObjCEncodingForType(PType, S);
4769    S += charUnitsToString(ParmOffset);
4770    ParmOffset += getObjCEncodingTypeSize(PType);
4771  }
4772
4773  return S;
4774}
4775
4776bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
4777                                                std::string& S) {
4778  // Encode result type.
4779  getObjCEncodingForType(Decl->getResultType(), S);
4780  CharUnits ParmOffset;
4781  // Compute size of all parameters.
4782  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4783       E = Decl->param_end(); PI != E; ++PI) {
4784    QualType PType = (*PI)->getType();
4785    CharUnits sz = getObjCEncodingTypeSize(PType);
4786    if (sz.isZero())
4787      continue;
4788
4789    assert (sz.isPositive() &&
4790        "getObjCEncodingForFunctionDecl - Incomplete param type");
4791    ParmOffset += sz;
4792  }
4793  S += charUnitsToString(ParmOffset);
4794  ParmOffset = CharUnits::Zero();
4795
4796  // Argument types.
4797  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4798       E = Decl->param_end(); PI != E; ++PI) {
4799    ParmVarDecl *PVDecl = *PI;
4800    QualType PType = PVDecl->getOriginalType();
4801    if (const ArrayType *AT =
4802          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4803      // Use array's original type only if it has known number of
4804      // elements.
4805      if (!isa<ConstantArrayType>(AT))
4806        PType = PVDecl->getType();
4807    } else if (PType->isFunctionType())
4808      PType = PVDecl->getType();
4809    getObjCEncodingForType(PType, S);
4810    S += charUnitsToString(ParmOffset);
4811    ParmOffset += getObjCEncodingTypeSize(PType);
4812  }
4813
4814  return false;
4815}
4816
4817/// getObjCEncodingForMethodParameter - Return the encoded type for a single
4818/// method parameter or return type. If Extended, include class names and
4819/// block object types.
4820void ASTContext::getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
4821                                                   QualType T, std::string& S,
4822                                                   bool Extended) const {
4823  // Encode type qualifer, 'in', 'inout', etc. for the parameter.
4824  getObjCEncodingForTypeQualifier(QT, S);
4825  // Encode parameter type.
4826  getObjCEncodingForTypeImpl(T, S, true, true, 0,
4827                             true     /*OutermostType*/,
4828                             false    /*EncodingProperty*/,
4829                             false    /*StructField*/,
4830                             Extended /*EncodeBlockParameters*/,
4831                             Extended /*EncodeClassNames*/);
4832}
4833
4834/// getObjCEncodingForMethodDecl - Return the encoded type for this method
4835/// declaration.
4836bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
4837                                              std::string& S,
4838                                              bool Extended) const {
4839  // FIXME: This is not very efficient.
4840  // Encode return type.
4841  getObjCEncodingForMethodParameter(Decl->getObjCDeclQualifier(),
4842                                    Decl->getResultType(), S, Extended);
4843  // Compute size of all parameters.
4844  // Start with computing size of a pointer in number of bytes.
4845  // FIXME: There might(should) be a better way of doing this computation!
4846  SourceLocation Loc;
4847  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4848  // The first two arguments (self and _cmd) are pointers; account for
4849  // their size.
4850  CharUnits ParmOffset = 2 * PtrSize;
4851  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4852       E = Decl->sel_param_end(); PI != E; ++PI) {
4853    QualType PType = (*PI)->getType();
4854    CharUnits sz = getObjCEncodingTypeSize(PType);
4855    if (sz.isZero())
4856      continue;
4857
4858    assert (sz.isPositive() &&
4859        "getObjCEncodingForMethodDecl - Incomplete param type");
4860    ParmOffset += sz;
4861  }
4862  S += charUnitsToString(ParmOffset);
4863  S += "@0:";
4864  S += charUnitsToString(PtrSize);
4865
4866  // Argument types.
4867  ParmOffset = 2 * PtrSize;
4868  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4869       E = Decl->sel_param_end(); PI != E; ++PI) {
4870    const ParmVarDecl *PVDecl = *PI;
4871    QualType PType = PVDecl->getOriginalType();
4872    if (const ArrayType *AT =
4873          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4874      // Use array's original type only if it has known number of
4875      // elements.
4876      if (!isa<ConstantArrayType>(AT))
4877        PType = PVDecl->getType();
4878    } else if (PType->isFunctionType())
4879      PType = PVDecl->getType();
4880    getObjCEncodingForMethodParameter(PVDecl->getObjCDeclQualifier(),
4881                                      PType, S, Extended);
4882    S += charUnitsToString(ParmOffset);
4883    ParmOffset += getObjCEncodingTypeSize(PType);
4884  }
4885
4886  return false;
4887}
4888
4889/// getObjCEncodingForPropertyDecl - Return the encoded type for this
4890/// property declaration. If non-NULL, Container must be either an
4891/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
4892/// NULL when getting encodings for protocol properties.
4893/// Property attributes are stored as a comma-delimited C string. The simple
4894/// attributes readonly and bycopy are encoded as single characters. The
4895/// parametrized attributes, getter=name, setter=name, and ivar=name, are
4896/// encoded as single characters, followed by an identifier. Property types
4897/// are also encoded as a parametrized attribute. The characters used to encode
4898/// these attributes are defined by the following enumeration:
4899/// @code
4900/// enum PropertyAttributes {
4901/// kPropertyReadOnly = 'R',   // property is read-only.
4902/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
4903/// kPropertyByref = '&',  // property is a reference to the value last assigned
4904/// kPropertyDynamic = 'D',    // property is dynamic
4905/// kPropertyGetter = 'G',     // followed by getter selector name
4906/// kPropertySetter = 'S',     // followed by setter selector name
4907/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
4908/// kPropertyType = 'T'              // followed by old-style type encoding.
4909/// kPropertyWeak = 'W'              // 'weak' property
4910/// kPropertyStrong = 'P'            // property GC'able
4911/// kPropertyNonAtomic = 'N'         // property non-atomic
4912/// };
4913/// @endcode
4914void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
4915                                                const Decl *Container,
4916                                                std::string& S) const {
4917  // Collect information from the property implementation decl(s).
4918  bool Dynamic = false;
4919  ObjCPropertyImplDecl *SynthesizePID = 0;
4920
4921  // FIXME: Duplicated code due to poor abstraction.
4922  if (Container) {
4923    if (const ObjCCategoryImplDecl *CID =
4924        dyn_cast<ObjCCategoryImplDecl>(Container)) {
4925      for (ObjCCategoryImplDecl::propimpl_iterator
4926             i = CID->propimpl_begin(), e = CID->propimpl_end();
4927           i != e; ++i) {
4928        ObjCPropertyImplDecl *PID = *i;
4929        if (PID->getPropertyDecl() == PD) {
4930          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4931            Dynamic = true;
4932          } else {
4933            SynthesizePID = PID;
4934          }
4935        }
4936      }
4937    } else {
4938      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
4939      for (ObjCCategoryImplDecl::propimpl_iterator
4940             i = OID->propimpl_begin(), e = OID->propimpl_end();
4941           i != e; ++i) {
4942        ObjCPropertyImplDecl *PID = *i;
4943        if (PID->getPropertyDecl() == PD) {
4944          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4945            Dynamic = true;
4946          } else {
4947            SynthesizePID = PID;
4948          }
4949        }
4950      }
4951    }
4952  }
4953
4954  // FIXME: This is not very efficient.
4955  S = "T";
4956
4957  // Encode result type.
4958  // GCC has some special rules regarding encoding of properties which
4959  // closely resembles encoding of ivars.
4960  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
4961                             true /* outermost type */,
4962                             true /* encoding for property */);
4963
4964  if (PD->isReadOnly()) {
4965    S += ",R";
4966    if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_copy)
4967      S += ",C";
4968    if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_retain)
4969      S += ",&";
4970  } else {
4971    switch (PD->getSetterKind()) {
4972    case ObjCPropertyDecl::Assign: break;
4973    case ObjCPropertyDecl::Copy:   S += ",C"; break;
4974    case ObjCPropertyDecl::Retain: S += ",&"; break;
4975    case ObjCPropertyDecl::Weak:   S += ",W"; break;
4976    }
4977  }
4978
4979  // It really isn't clear at all what this means, since properties
4980  // are "dynamic by default".
4981  if (Dynamic)
4982    S += ",D";
4983
4984  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
4985    S += ",N";
4986
4987  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
4988    S += ",G";
4989    S += PD->getGetterName().getAsString();
4990  }
4991
4992  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
4993    S += ",S";
4994    S += PD->getSetterName().getAsString();
4995  }
4996
4997  if (SynthesizePID) {
4998    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
4999    S += ",V";
5000    S += OID->getNameAsString();
5001  }
5002
5003  // FIXME: OBJCGC: weak & strong
5004}
5005
5006/// getLegacyIntegralTypeEncoding -
5007/// Another legacy compatibility encoding: 32-bit longs are encoded as
5008/// 'l' or 'L' , but not always.  For typedefs, we need to use
5009/// 'i' or 'I' instead if encoding a struct field, or a pointer!
5010///
5011void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
5012  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
5013    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
5014      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
5015        PointeeTy = UnsignedIntTy;
5016      else
5017        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
5018          PointeeTy = IntTy;
5019    }
5020  }
5021}
5022
5023void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
5024                                        const FieldDecl *Field) const {
5025  // We follow the behavior of gcc, expanding structures which are
5026  // directly pointed to, and expanding embedded structures. Note that
5027  // these rules are sufficient to prevent recursive encoding of the
5028  // same type.
5029  getObjCEncodingForTypeImpl(T, S, true, true, Field,
5030                             true /* outermost type */);
5031}
5032
5033static char getObjCEncodingForPrimitiveKind(const ASTContext *C,
5034                                            BuiltinType::Kind kind) {
5035    switch (kind) {
5036    case BuiltinType::Void:       return 'v';
5037    case BuiltinType::Bool:       return 'B';
5038    case BuiltinType::Char_U:
5039    case BuiltinType::UChar:      return 'C';
5040    case BuiltinType::Char16:
5041    case BuiltinType::UShort:     return 'S';
5042    case BuiltinType::Char32:
5043    case BuiltinType::UInt:       return 'I';
5044    case BuiltinType::ULong:
5045        return C->getTargetInfo().getLongWidth() == 32 ? 'L' : 'Q';
5046    case BuiltinType::UInt128:    return 'T';
5047    case BuiltinType::ULongLong:  return 'Q';
5048    case BuiltinType::Char_S:
5049    case BuiltinType::SChar:      return 'c';
5050    case BuiltinType::Short:      return 's';
5051    case BuiltinType::WChar_S:
5052    case BuiltinType::WChar_U:
5053    case BuiltinType::Int:        return 'i';
5054    case BuiltinType::Long:
5055      return C->getTargetInfo().getLongWidth() == 32 ? 'l' : 'q';
5056    case BuiltinType::LongLong:   return 'q';
5057    case BuiltinType::Int128:     return 't';
5058    case BuiltinType::Float:      return 'f';
5059    case BuiltinType::Double:     return 'd';
5060    case BuiltinType::LongDouble: return 'D';
5061    case BuiltinType::NullPtr:    return '*'; // like char*
5062
5063    case BuiltinType::Half:
5064      // FIXME: potentially need @encodes for these!
5065      return ' ';
5066
5067    case BuiltinType::ObjCId:
5068    case BuiltinType::ObjCClass:
5069    case BuiltinType::ObjCSel:
5070      llvm_unreachable("@encoding ObjC primitive type");
5071
5072    // OpenCL and placeholder types don't need @encodings.
5073    case BuiltinType::OCLImage1d:
5074    case BuiltinType::OCLImage1dArray:
5075    case BuiltinType::OCLImage1dBuffer:
5076    case BuiltinType::OCLImage2d:
5077    case BuiltinType::OCLImage2dArray:
5078    case BuiltinType::OCLImage3d:
5079    case BuiltinType::OCLEvent:
5080    case BuiltinType::OCLSampler:
5081    case BuiltinType::Dependent:
5082#define BUILTIN_TYPE(KIND, ID)
5083#define PLACEHOLDER_TYPE(KIND, ID) \
5084    case BuiltinType::KIND:
5085#include "clang/AST/BuiltinTypes.def"
5086      llvm_unreachable("invalid builtin type for @encode");
5087    }
5088    llvm_unreachable("invalid BuiltinType::Kind value");
5089}
5090
5091static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
5092  EnumDecl *Enum = ET->getDecl();
5093
5094  // The encoding of an non-fixed enum type is always 'i', regardless of size.
5095  if (!Enum->isFixed())
5096    return 'i';
5097
5098  // The encoding of a fixed enum type matches its fixed underlying type.
5099  const BuiltinType *BT = Enum->getIntegerType()->castAs<BuiltinType>();
5100  return getObjCEncodingForPrimitiveKind(C, BT->getKind());
5101}
5102
5103static void EncodeBitField(const ASTContext *Ctx, std::string& S,
5104                           QualType T, const FieldDecl *FD) {
5105  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
5106  S += 'b';
5107  // The NeXT runtime encodes bit fields as b followed by the number of bits.
5108  // The GNU runtime requires more information; bitfields are encoded as b,
5109  // then the offset (in bits) of the first element, then the type of the
5110  // bitfield, then the size in bits.  For example, in this structure:
5111  //
5112  // struct
5113  // {
5114  //    int integer;
5115  //    int flags:2;
5116  // };
5117  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
5118  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
5119  // information is not especially sensible, but we're stuck with it for
5120  // compatibility with GCC, although providing it breaks anything that
5121  // actually uses runtime introspection and wants to work on both runtimes...
5122  if (Ctx->getLangOpts().ObjCRuntime.isGNUFamily()) {
5123    const RecordDecl *RD = FD->getParent();
5124    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
5125    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
5126    if (const EnumType *ET = T->getAs<EnumType>())
5127      S += ObjCEncodingForEnumType(Ctx, ET);
5128    else {
5129      const BuiltinType *BT = T->castAs<BuiltinType>();
5130      S += getObjCEncodingForPrimitiveKind(Ctx, BT->getKind());
5131    }
5132  }
5133  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
5134}
5135
5136// FIXME: Use SmallString for accumulating string.
5137void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
5138                                            bool ExpandPointedToStructures,
5139                                            bool ExpandStructures,
5140                                            const FieldDecl *FD,
5141                                            bool OutermostType,
5142                                            bool EncodingProperty,
5143                                            bool StructField,
5144                                            bool EncodeBlockParameters,
5145                                            bool EncodeClassNames,
5146                                            bool EncodePointerToObjCTypedef) const {
5147  CanQualType CT = getCanonicalType(T);
5148  switch (CT->getTypeClass()) {
5149  case Type::Builtin:
5150  case Type::Enum:
5151    if (FD && FD->isBitField())
5152      return EncodeBitField(this, S, T, FD);
5153    if (const BuiltinType *BT = dyn_cast<BuiltinType>(CT))
5154      S += getObjCEncodingForPrimitiveKind(this, BT->getKind());
5155    else
5156      S += ObjCEncodingForEnumType(this, cast<EnumType>(CT));
5157    return;
5158
5159  case Type::Complex: {
5160    const ComplexType *CT = T->castAs<ComplexType>();
5161    S += 'j';
5162    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
5163                               false);
5164    return;
5165  }
5166
5167  case Type::Atomic: {
5168    const AtomicType *AT = T->castAs<AtomicType>();
5169    S += 'A';
5170    getObjCEncodingForTypeImpl(AT->getValueType(), S, false, false, 0,
5171                               false, false);
5172    return;
5173  }
5174
5175  // encoding for pointer or reference types.
5176  case Type::Pointer:
5177  case Type::LValueReference:
5178  case Type::RValueReference: {
5179    QualType PointeeTy;
5180    if (isa<PointerType>(CT)) {
5181      const PointerType *PT = T->castAs<PointerType>();
5182      if (PT->isObjCSelType()) {
5183        S += ':';
5184        return;
5185      }
5186      PointeeTy = PT->getPointeeType();
5187    } else {
5188      PointeeTy = T->castAs<ReferenceType>()->getPointeeType();
5189    }
5190
5191    bool isReadOnly = false;
5192    // For historical/compatibility reasons, the read-only qualifier of the
5193    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
5194    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
5195    // Also, do not emit the 'r' for anything but the outermost type!
5196    if (isa<TypedefType>(T.getTypePtr())) {
5197      if (OutermostType && T.isConstQualified()) {
5198        isReadOnly = true;
5199        S += 'r';
5200      }
5201    } else if (OutermostType) {
5202      QualType P = PointeeTy;
5203      while (P->getAs<PointerType>())
5204        P = P->getAs<PointerType>()->getPointeeType();
5205      if (P.isConstQualified()) {
5206        isReadOnly = true;
5207        S += 'r';
5208      }
5209    }
5210    if (isReadOnly) {
5211      // Another legacy compatibility encoding. Some ObjC qualifier and type
5212      // combinations need to be rearranged.
5213      // Rewrite "in const" from "nr" to "rn"
5214      if (StringRef(S).endswith("nr"))
5215        S.replace(S.end()-2, S.end(), "rn");
5216    }
5217
5218    if (PointeeTy->isCharType()) {
5219      // char pointer types should be encoded as '*' unless it is a
5220      // type that has been typedef'd to 'BOOL'.
5221      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
5222        S += '*';
5223        return;
5224      }
5225    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
5226      // GCC binary compat: Need to convert "struct objc_class *" to "#".
5227      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
5228        S += '#';
5229        return;
5230      }
5231      // GCC binary compat: Need to convert "struct objc_object *" to "@".
5232      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
5233        S += '@';
5234        return;
5235      }
5236      // fall through...
5237    }
5238    S += '^';
5239    getLegacyIntegralTypeEncoding(PointeeTy);
5240
5241    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
5242                               NULL);
5243    return;
5244  }
5245
5246  case Type::ConstantArray:
5247  case Type::IncompleteArray:
5248  case Type::VariableArray: {
5249    const ArrayType *AT = cast<ArrayType>(CT);
5250
5251    if (isa<IncompleteArrayType>(AT) && !StructField) {
5252      // Incomplete arrays are encoded as a pointer to the array element.
5253      S += '^';
5254
5255      getObjCEncodingForTypeImpl(AT->getElementType(), S,
5256                                 false, ExpandStructures, FD);
5257    } else {
5258      S += '[';
5259
5260      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
5261        S += llvm::utostr(CAT->getSize().getZExtValue());
5262      else {
5263        //Variable length arrays are encoded as a regular array with 0 elements.
5264        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
5265               "Unknown array type!");
5266        S += '0';
5267      }
5268
5269      getObjCEncodingForTypeImpl(AT->getElementType(), S,
5270                                 false, ExpandStructures, FD);
5271      S += ']';
5272    }
5273    return;
5274  }
5275
5276  case Type::FunctionNoProto:
5277  case Type::FunctionProto:
5278    S += '?';
5279    return;
5280
5281  case Type::Record: {
5282    RecordDecl *RDecl = cast<RecordType>(CT)->getDecl();
5283    S += RDecl->isUnion() ? '(' : '{';
5284    // Anonymous structures print as '?'
5285    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
5286      S += II->getName();
5287      if (ClassTemplateSpecializationDecl *Spec
5288          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
5289        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
5290        llvm::raw_string_ostream OS(S);
5291        TemplateSpecializationType::PrintTemplateArgumentList(OS,
5292                                            TemplateArgs.data(),
5293                                            TemplateArgs.size(),
5294                                            (*this).getPrintingPolicy());
5295      }
5296    } else {
5297      S += '?';
5298    }
5299    if (ExpandStructures) {
5300      S += '=';
5301      if (!RDecl->isUnion()) {
5302        getObjCEncodingForStructureImpl(RDecl, S, FD);
5303      } else {
5304        for (RecordDecl::field_iterator Field = RDecl->field_begin(),
5305                                     FieldEnd = RDecl->field_end();
5306             Field != FieldEnd; ++Field) {
5307          if (FD) {
5308            S += '"';
5309            S += Field->getNameAsString();
5310            S += '"';
5311          }
5312
5313          // Special case bit-fields.
5314          if (Field->isBitField()) {
5315            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
5316                                       *Field);
5317          } else {
5318            QualType qt = Field->getType();
5319            getLegacyIntegralTypeEncoding(qt);
5320            getObjCEncodingForTypeImpl(qt, S, false, true,
5321                                       FD, /*OutermostType*/false,
5322                                       /*EncodingProperty*/false,
5323                                       /*StructField*/true);
5324          }
5325        }
5326      }
5327    }
5328    S += RDecl->isUnion() ? ')' : '}';
5329    return;
5330  }
5331
5332  case Type::BlockPointer: {
5333    const BlockPointerType *BT = T->castAs<BlockPointerType>();
5334    S += "@?"; // Unlike a pointer-to-function, which is "^?".
5335    if (EncodeBlockParameters) {
5336      const FunctionType *FT = BT->getPointeeType()->castAs<FunctionType>();
5337
5338      S += '<';
5339      // Block return type
5340      getObjCEncodingForTypeImpl(FT->getResultType(), S,
5341                                 ExpandPointedToStructures, ExpandStructures,
5342                                 FD,
5343                                 false /* OutermostType */,
5344                                 EncodingProperty,
5345                                 false /* StructField */,
5346                                 EncodeBlockParameters,
5347                                 EncodeClassNames);
5348      // Block self
5349      S += "@?";
5350      // Block parameters
5351      if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT)) {
5352        for (FunctionProtoType::arg_type_iterator I = FPT->arg_type_begin(),
5353               E = FPT->arg_type_end(); I && (I != E); ++I) {
5354          getObjCEncodingForTypeImpl(*I, S,
5355                                     ExpandPointedToStructures,
5356                                     ExpandStructures,
5357                                     FD,
5358                                     false /* OutermostType */,
5359                                     EncodingProperty,
5360                                     false /* StructField */,
5361                                     EncodeBlockParameters,
5362                                     EncodeClassNames);
5363        }
5364      }
5365      S += '>';
5366    }
5367    return;
5368  }
5369
5370  case Type::ObjCObject:
5371  case Type::ObjCInterface: {
5372    // Ignore protocol qualifiers when mangling at this level.
5373    T = T->castAs<ObjCObjectType>()->getBaseType();
5374
5375    // The assumption seems to be that this assert will succeed
5376    // because nested levels will have filtered out 'id' and 'Class'.
5377    const ObjCInterfaceType *OIT = T->castAs<ObjCInterfaceType>();
5378    // @encode(class_name)
5379    ObjCInterfaceDecl *OI = OIT->getDecl();
5380    S += '{';
5381    const IdentifierInfo *II = OI->getIdentifier();
5382    S += II->getName();
5383    S += '=';
5384    SmallVector<const ObjCIvarDecl*, 32> Ivars;
5385    DeepCollectObjCIvars(OI, true, Ivars);
5386    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
5387      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
5388      if (Field->isBitField())
5389        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
5390      else
5391        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD,
5392                                   false, false, false, false, false,
5393                                   EncodePointerToObjCTypedef);
5394    }
5395    S += '}';
5396    return;
5397  }
5398
5399  case Type::ObjCObjectPointer: {
5400    const ObjCObjectPointerType *OPT = T->castAs<ObjCObjectPointerType>();
5401    if (OPT->isObjCIdType()) {
5402      S += '@';
5403      return;
5404    }
5405
5406    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
5407      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
5408      // Since this is a binary compatibility issue, need to consult with runtime
5409      // folks. Fortunately, this is a *very* obsure construct.
5410      S += '#';
5411      return;
5412    }
5413
5414    if (OPT->isObjCQualifiedIdType()) {
5415      getObjCEncodingForTypeImpl(getObjCIdType(), S,
5416                                 ExpandPointedToStructures,
5417                                 ExpandStructures, FD);
5418      if (FD || EncodingProperty || EncodeClassNames) {
5419        // Note that we do extended encoding of protocol qualifer list
5420        // Only when doing ivar or property encoding.
5421        S += '"';
5422        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
5423             E = OPT->qual_end(); I != E; ++I) {
5424          S += '<';
5425          S += (*I)->getNameAsString();
5426          S += '>';
5427        }
5428        S += '"';
5429      }
5430      return;
5431    }
5432
5433    QualType PointeeTy = OPT->getPointeeType();
5434    if (!EncodingProperty &&
5435        isa<TypedefType>(PointeeTy.getTypePtr()) &&
5436        !EncodePointerToObjCTypedef) {
5437      // Another historical/compatibility reason.
5438      // We encode the underlying type which comes out as
5439      // {...};
5440      S += '^';
5441      if (FD && OPT->getInterfaceDecl()) {
5442        // Prevent recursive encoding of fields in some rare cases.
5443        ObjCInterfaceDecl *OI = OPT->getInterfaceDecl();
5444        SmallVector<const ObjCIvarDecl*, 32> Ivars;
5445        DeepCollectObjCIvars(OI, true, Ivars);
5446        for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
5447          if (cast<FieldDecl>(Ivars[i]) == FD) {
5448            S += '{';
5449            S += OI->getIdentifier()->getName();
5450            S += '}';
5451            return;
5452          }
5453        }
5454      }
5455      getObjCEncodingForTypeImpl(PointeeTy, S,
5456                                 false, ExpandPointedToStructures,
5457                                 NULL,
5458                                 false, false, false, false, false,
5459                                 /*EncodePointerToObjCTypedef*/true);
5460      return;
5461    }
5462
5463    S += '@';
5464    if (OPT->getInterfaceDecl() &&
5465        (FD || EncodingProperty || EncodeClassNames)) {
5466      S += '"';
5467      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
5468      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
5469           E = OPT->qual_end(); I != E; ++I) {
5470        S += '<';
5471        S += (*I)->getNameAsString();
5472        S += '>';
5473      }
5474      S += '"';
5475    }
5476    return;
5477  }
5478
5479  // gcc just blithely ignores member pointers.
5480  // FIXME: we shoul do better than that.  'M' is available.
5481  case Type::MemberPointer:
5482    return;
5483
5484  case Type::Vector:
5485  case Type::ExtVector:
5486    // This matches gcc's encoding, even though technically it is
5487    // insufficient.
5488    // FIXME. We should do a better job than gcc.
5489    return;
5490
5491  case Type::Auto:
5492    // We could see an undeduced auto type here during error recovery.
5493    // Just ignore it.
5494    return;
5495
5496#define ABSTRACT_TYPE(KIND, BASE)
5497#define TYPE(KIND, BASE)
5498#define DEPENDENT_TYPE(KIND, BASE) \
5499  case Type::KIND:
5500#define NON_CANONICAL_TYPE(KIND, BASE) \
5501  case Type::KIND:
5502#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(KIND, BASE) \
5503  case Type::KIND:
5504#include "clang/AST/TypeNodes.def"
5505    llvm_unreachable("@encode for dependent type!");
5506  }
5507  llvm_unreachable("bad type kind!");
5508}
5509
5510void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
5511                                                 std::string &S,
5512                                                 const FieldDecl *FD,
5513                                                 bool includeVBases) const {
5514  assert(RDecl && "Expected non-null RecordDecl");
5515  assert(!RDecl->isUnion() && "Should not be called for unions");
5516  if (!RDecl->getDefinition())
5517    return;
5518
5519  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
5520  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
5521  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
5522
5523  if (CXXRec) {
5524    for (CXXRecordDecl::base_class_iterator
5525           BI = CXXRec->bases_begin(),
5526           BE = CXXRec->bases_end(); BI != BE; ++BI) {
5527      if (!BI->isVirtual()) {
5528        CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
5529        if (base->isEmpty())
5530          continue;
5531        uint64_t offs = toBits(layout.getBaseClassOffset(base));
5532        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5533                                  std::make_pair(offs, base));
5534      }
5535    }
5536  }
5537
5538  unsigned i = 0;
5539  for (RecordDecl::field_iterator Field = RDecl->field_begin(),
5540                               FieldEnd = RDecl->field_end();
5541       Field != FieldEnd; ++Field, ++i) {
5542    uint64_t offs = layout.getFieldOffset(i);
5543    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5544                              std::make_pair(offs, *Field));
5545  }
5546
5547  if (CXXRec && includeVBases) {
5548    for (CXXRecordDecl::base_class_iterator
5549           BI = CXXRec->vbases_begin(),
5550           BE = CXXRec->vbases_end(); BI != BE; ++BI) {
5551      CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
5552      if (base->isEmpty())
5553        continue;
5554      uint64_t offs = toBits(layout.getVBaseClassOffset(base));
5555      if (offs >= uint64_t(toBits(layout.getNonVirtualSize())) &&
5556          FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
5557        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
5558                                  std::make_pair(offs, base));
5559    }
5560  }
5561
5562  CharUnits size;
5563  if (CXXRec) {
5564    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
5565  } else {
5566    size = layout.getSize();
5567  }
5568
5569  uint64_t CurOffs = 0;
5570  std::multimap<uint64_t, NamedDecl *>::iterator
5571    CurLayObj = FieldOrBaseOffsets.begin();
5572
5573  if (CXXRec && CXXRec->isDynamicClass() &&
5574      (CurLayObj == FieldOrBaseOffsets.end() || CurLayObj->first != 0)) {
5575    if (FD) {
5576      S += "\"_vptr$";
5577      std::string recname = CXXRec->getNameAsString();
5578      if (recname.empty()) recname = "?";
5579      S += recname;
5580      S += '"';
5581    }
5582    S += "^^?";
5583    CurOffs += getTypeSize(VoidPtrTy);
5584  }
5585
5586  if (!RDecl->hasFlexibleArrayMember()) {
5587    // Mark the end of the structure.
5588    uint64_t offs = toBits(size);
5589    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5590                              std::make_pair(offs, (NamedDecl*)0));
5591  }
5592
5593  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
5594    assert(CurOffs <= CurLayObj->first);
5595
5596    if (CurOffs < CurLayObj->first) {
5597      uint64_t padding = CurLayObj->first - CurOffs;
5598      // FIXME: There doesn't seem to be a way to indicate in the encoding that
5599      // packing/alignment of members is different that normal, in which case
5600      // the encoding will be out-of-sync with the real layout.
5601      // If the runtime switches to just consider the size of types without
5602      // taking into account alignment, we could make padding explicit in the
5603      // encoding (e.g. using arrays of chars). The encoding strings would be
5604      // longer then though.
5605      CurOffs += padding;
5606    }
5607
5608    NamedDecl *dcl = CurLayObj->second;
5609    if (dcl == 0)
5610      break; // reached end of structure.
5611
5612    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
5613      // We expand the bases without their virtual bases since those are going
5614      // in the initial structure. Note that this differs from gcc which
5615      // expands virtual bases each time one is encountered in the hierarchy,
5616      // making the encoding type bigger than it really is.
5617      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false);
5618      assert(!base->isEmpty());
5619      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
5620    } else {
5621      FieldDecl *field = cast<FieldDecl>(dcl);
5622      if (FD) {
5623        S += '"';
5624        S += field->getNameAsString();
5625        S += '"';
5626      }
5627
5628      if (field->isBitField()) {
5629        EncodeBitField(this, S, field->getType(), field);
5630        CurOffs += field->getBitWidthValue(*this);
5631      } else {
5632        QualType qt = field->getType();
5633        getLegacyIntegralTypeEncoding(qt);
5634        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
5635                                   /*OutermostType*/false,
5636                                   /*EncodingProperty*/false,
5637                                   /*StructField*/true);
5638        CurOffs += getTypeSize(field->getType());
5639      }
5640    }
5641  }
5642}
5643
5644void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
5645                                                 std::string& S) const {
5646  if (QT & Decl::OBJC_TQ_In)
5647    S += 'n';
5648  if (QT & Decl::OBJC_TQ_Inout)
5649    S += 'N';
5650  if (QT & Decl::OBJC_TQ_Out)
5651    S += 'o';
5652  if (QT & Decl::OBJC_TQ_Bycopy)
5653    S += 'O';
5654  if (QT & Decl::OBJC_TQ_Byref)
5655    S += 'R';
5656  if (QT & Decl::OBJC_TQ_Oneway)
5657    S += 'V';
5658}
5659
5660TypedefDecl *ASTContext::getObjCIdDecl() const {
5661  if (!ObjCIdDecl) {
5662    QualType T = getObjCObjectType(ObjCBuiltinIdTy, 0, 0);
5663    T = getObjCObjectPointerType(T);
5664    TypeSourceInfo *IdInfo = getTrivialTypeSourceInfo(T);
5665    ObjCIdDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
5666                                     getTranslationUnitDecl(),
5667                                     SourceLocation(), SourceLocation(),
5668                                     &Idents.get("id"), IdInfo);
5669  }
5670
5671  return ObjCIdDecl;
5672}
5673
5674TypedefDecl *ASTContext::getObjCSelDecl() const {
5675  if (!ObjCSelDecl) {
5676    QualType SelT = getPointerType(ObjCBuiltinSelTy);
5677    TypeSourceInfo *SelInfo = getTrivialTypeSourceInfo(SelT);
5678    ObjCSelDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
5679                                      getTranslationUnitDecl(),
5680                                      SourceLocation(), SourceLocation(),
5681                                      &Idents.get("SEL"), SelInfo);
5682  }
5683  return ObjCSelDecl;
5684}
5685
5686TypedefDecl *ASTContext::getObjCClassDecl() const {
5687  if (!ObjCClassDecl) {
5688    QualType T = getObjCObjectType(ObjCBuiltinClassTy, 0, 0);
5689    T = getObjCObjectPointerType(T);
5690    TypeSourceInfo *ClassInfo = getTrivialTypeSourceInfo(T);
5691    ObjCClassDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
5692                                        getTranslationUnitDecl(),
5693                                        SourceLocation(), SourceLocation(),
5694                                        &Idents.get("Class"), ClassInfo);
5695  }
5696
5697  return ObjCClassDecl;
5698}
5699
5700ObjCInterfaceDecl *ASTContext::getObjCProtocolDecl() const {
5701  if (!ObjCProtocolClassDecl) {
5702    ObjCProtocolClassDecl
5703      = ObjCInterfaceDecl::Create(*this, getTranslationUnitDecl(),
5704                                  SourceLocation(),
5705                                  &Idents.get("Protocol"),
5706                                  /*PrevDecl=*/0,
5707                                  SourceLocation(), true);
5708  }
5709
5710  return ObjCProtocolClassDecl;
5711}
5712
5713//===----------------------------------------------------------------------===//
5714// __builtin_va_list Construction Functions
5715//===----------------------------------------------------------------------===//
5716
5717static TypedefDecl *CreateCharPtrBuiltinVaListDecl(const ASTContext *Context) {
5718  // typedef char* __builtin_va_list;
5719  QualType CharPtrType = Context->getPointerType(Context->CharTy);
5720  TypeSourceInfo *TInfo
5721    = Context->getTrivialTypeSourceInfo(CharPtrType);
5722
5723  TypedefDecl *VaListTypeDecl
5724    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5725                          Context->getTranslationUnitDecl(),
5726                          SourceLocation(), SourceLocation(),
5727                          &Context->Idents.get("__builtin_va_list"),
5728                          TInfo);
5729  return VaListTypeDecl;
5730}
5731
5732static TypedefDecl *CreateVoidPtrBuiltinVaListDecl(const ASTContext *Context) {
5733  // typedef void* __builtin_va_list;
5734  QualType VoidPtrType = Context->getPointerType(Context->VoidTy);
5735  TypeSourceInfo *TInfo
5736    = Context->getTrivialTypeSourceInfo(VoidPtrType);
5737
5738  TypedefDecl *VaListTypeDecl
5739    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5740                          Context->getTranslationUnitDecl(),
5741                          SourceLocation(), SourceLocation(),
5742                          &Context->Idents.get("__builtin_va_list"),
5743                          TInfo);
5744  return VaListTypeDecl;
5745}
5746
5747static TypedefDecl *
5748CreateAArch64ABIBuiltinVaListDecl(const ASTContext *Context) {
5749  RecordDecl *VaListTagDecl;
5750  if (Context->getLangOpts().CPlusPlus) {
5751    // namespace std { struct __va_list {
5752    NamespaceDecl *NS;
5753    NS = NamespaceDecl::Create(const_cast<ASTContext &>(*Context),
5754                               Context->getTranslationUnitDecl(),
5755                               /*Inline*/false, SourceLocation(),
5756                               SourceLocation(), &Context->Idents.get("std"),
5757                               /*PrevDecl*/0);
5758
5759    VaListTagDecl = CXXRecordDecl::Create(*Context, TTK_Struct,
5760                                          Context->getTranslationUnitDecl(),
5761                                          SourceLocation(), SourceLocation(),
5762                                          &Context->Idents.get("__va_list"));
5763    VaListTagDecl->setDeclContext(NS);
5764  } else {
5765    // struct __va_list
5766    VaListTagDecl = CreateRecordDecl(*Context, TTK_Struct,
5767                                   Context->getTranslationUnitDecl(),
5768                                   &Context->Idents.get("__va_list"));
5769  }
5770
5771  VaListTagDecl->startDefinition();
5772
5773  const size_t NumFields = 5;
5774  QualType FieldTypes[NumFields];
5775  const char *FieldNames[NumFields];
5776
5777  // void *__stack;
5778  FieldTypes[0] = Context->getPointerType(Context->VoidTy);
5779  FieldNames[0] = "__stack";
5780
5781  // void *__gr_top;
5782  FieldTypes[1] = Context->getPointerType(Context->VoidTy);
5783  FieldNames[1] = "__gr_top";
5784
5785  // void *__vr_top;
5786  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
5787  FieldNames[2] = "__vr_top";
5788
5789  // int __gr_offs;
5790  FieldTypes[3] = Context->IntTy;
5791  FieldNames[3] = "__gr_offs";
5792
5793  // int __vr_offs;
5794  FieldTypes[4] = Context->IntTy;
5795  FieldNames[4] = "__vr_offs";
5796
5797  // Create fields
5798  for (unsigned i = 0; i < NumFields; ++i) {
5799    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
5800                                         VaListTagDecl,
5801                                         SourceLocation(),
5802                                         SourceLocation(),
5803                                         &Context->Idents.get(FieldNames[i]),
5804                                         FieldTypes[i], /*TInfo=*/0,
5805                                         /*BitWidth=*/0,
5806                                         /*Mutable=*/false,
5807                                         ICIS_NoInit);
5808    Field->setAccess(AS_public);
5809    VaListTagDecl->addDecl(Field);
5810  }
5811  VaListTagDecl->completeDefinition();
5812  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
5813  Context->VaListTagTy = VaListTagType;
5814
5815  // } __builtin_va_list;
5816  TypedefDecl *VaListTypedefDecl
5817    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5818                          Context->getTranslationUnitDecl(),
5819                          SourceLocation(), SourceLocation(),
5820                          &Context->Idents.get("__builtin_va_list"),
5821                          Context->getTrivialTypeSourceInfo(VaListTagType));
5822
5823  return VaListTypedefDecl;
5824}
5825
5826static TypedefDecl *CreatePowerABIBuiltinVaListDecl(const ASTContext *Context) {
5827  // typedef struct __va_list_tag {
5828  RecordDecl *VaListTagDecl;
5829
5830  VaListTagDecl = CreateRecordDecl(*Context, TTK_Struct,
5831                                   Context->getTranslationUnitDecl(),
5832                                   &Context->Idents.get("__va_list_tag"));
5833  VaListTagDecl->startDefinition();
5834
5835  const size_t NumFields = 5;
5836  QualType FieldTypes[NumFields];
5837  const char *FieldNames[NumFields];
5838
5839  //   unsigned char gpr;
5840  FieldTypes[0] = Context->UnsignedCharTy;
5841  FieldNames[0] = "gpr";
5842
5843  //   unsigned char fpr;
5844  FieldTypes[1] = Context->UnsignedCharTy;
5845  FieldNames[1] = "fpr";
5846
5847  //   unsigned short reserved;
5848  FieldTypes[2] = Context->UnsignedShortTy;
5849  FieldNames[2] = "reserved";
5850
5851  //   void* overflow_arg_area;
5852  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
5853  FieldNames[3] = "overflow_arg_area";
5854
5855  //   void* reg_save_area;
5856  FieldTypes[4] = Context->getPointerType(Context->VoidTy);
5857  FieldNames[4] = "reg_save_area";
5858
5859  // Create fields
5860  for (unsigned i = 0; i < NumFields; ++i) {
5861    FieldDecl *Field = FieldDecl::Create(*Context, VaListTagDecl,
5862                                         SourceLocation(),
5863                                         SourceLocation(),
5864                                         &Context->Idents.get(FieldNames[i]),
5865                                         FieldTypes[i], /*TInfo=*/0,
5866                                         /*BitWidth=*/0,
5867                                         /*Mutable=*/false,
5868                                         ICIS_NoInit);
5869    Field->setAccess(AS_public);
5870    VaListTagDecl->addDecl(Field);
5871  }
5872  VaListTagDecl->completeDefinition();
5873  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
5874  Context->VaListTagTy = VaListTagType;
5875
5876  // } __va_list_tag;
5877  TypedefDecl *VaListTagTypedefDecl
5878    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5879                          Context->getTranslationUnitDecl(),
5880                          SourceLocation(), SourceLocation(),
5881                          &Context->Idents.get("__va_list_tag"),
5882                          Context->getTrivialTypeSourceInfo(VaListTagType));
5883  QualType VaListTagTypedefType =
5884    Context->getTypedefType(VaListTagTypedefDecl);
5885
5886  // typedef __va_list_tag __builtin_va_list[1];
5887  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
5888  QualType VaListTagArrayType
5889    = Context->getConstantArrayType(VaListTagTypedefType,
5890                                    Size, ArrayType::Normal, 0);
5891  TypeSourceInfo *TInfo
5892    = Context->getTrivialTypeSourceInfo(VaListTagArrayType);
5893  TypedefDecl *VaListTypedefDecl
5894    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5895                          Context->getTranslationUnitDecl(),
5896                          SourceLocation(), SourceLocation(),
5897                          &Context->Idents.get("__builtin_va_list"),
5898                          TInfo);
5899
5900  return VaListTypedefDecl;
5901}
5902
5903static TypedefDecl *
5904CreateX86_64ABIBuiltinVaListDecl(const ASTContext *Context) {
5905  // typedef struct __va_list_tag {
5906  RecordDecl *VaListTagDecl;
5907  VaListTagDecl = CreateRecordDecl(*Context, TTK_Struct,
5908                                   Context->getTranslationUnitDecl(),
5909                                   &Context->Idents.get("__va_list_tag"));
5910  VaListTagDecl->startDefinition();
5911
5912  const size_t NumFields = 4;
5913  QualType FieldTypes[NumFields];
5914  const char *FieldNames[NumFields];
5915
5916  //   unsigned gp_offset;
5917  FieldTypes[0] = Context->UnsignedIntTy;
5918  FieldNames[0] = "gp_offset";
5919
5920  //   unsigned fp_offset;
5921  FieldTypes[1] = Context->UnsignedIntTy;
5922  FieldNames[1] = "fp_offset";
5923
5924  //   void* overflow_arg_area;
5925  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
5926  FieldNames[2] = "overflow_arg_area";
5927
5928  //   void* reg_save_area;
5929  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
5930  FieldNames[3] = "reg_save_area";
5931
5932  // Create fields
5933  for (unsigned i = 0; i < NumFields; ++i) {
5934    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
5935                                         VaListTagDecl,
5936                                         SourceLocation(),
5937                                         SourceLocation(),
5938                                         &Context->Idents.get(FieldNames[i]),
5939                                         FieldTypes[i], /*TInfo=*/0,
5940                                         /*BitWidth=*/0,
5941                                         /*Mutable=*/false,
5942                                         ICIS_NoInit);
5943    Field->setAccess(AS_public);
5944    VaListTagDecl->addDecl(Field);
5945  }
5946  VaListTagDecl->completeDefinition();
5947  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
5948  Context->VaListTagTy = VaListTagType;
5949
5950  // } __va_list_tag;
5951  TypedefDecl *VaListTagTypedefDecl
5952    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5953                          Context->getTranslationUnitDecl(),
5954                          SourceLocation(), SourceLocation(),
5955                          &Context->Idents.get("__va_list_tag"),
5956                          Context->getTrivialTypeSourceInfo(VaListTagType));
5957  QualType VaListTagTypedefType =
5958    Context->getTypedefType(VaListTagTypedefDecl);
5959
5960  // typedef __va_list_tag __builtin_va_list[1];
5961  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
5962  QualType VaListTagArrayType
5963    = Context->getConstantArrayType(VaListTagTypedefType,
5964                                      Size, ArrayType::Normal,0);
5965  TypeSourceInfo *TInfo
5966    = Context->getTrivialTypeSourceInfo(VaListTagArrayType);
5967  TypedefDecl *VaListTypedefDecl
5968    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5969                          Context->getTranslationUnitDecl(),
5970                          SourceLocation(), SourceLocation(),
5971                          &Context->Idents.get("__builtin_va_list"),
5972                          TInfo);
5973
5974  return VaListTypedefDecl;
5975}
5976
5977static TypedefDecl *CreatePNaClABIBuiltinVaListDecl(const ASTContext *Context) {
5978  // typedef int __builtin_va_list[4];
5979  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 4);
5980  QualType IntArrayType
5981    = Context->getConstantArrayType(Context->IntTy,
5982				    Size, ArrayType::Normal, 0);
5983  TypedefDecl *VaListTypedefDecl
5984    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5985                          Context->getTranslationUnitDecl(),
5986                          SourceLocation(), SourceLocation(),
5987                          &Context->Idents.get("__builtin_va_list"),
5988                          Context->getTrivialTypeSourceInfo(IntArrayType));
5989
5990  return VaListTypedefDecl;
5991}
5992
5993static TypedefDecl *
5994CreateAAPCSABIBuiltinVaListDecl(const ASTContext *Context) {
5995  RecordDecl *VaListDecl;
5996  if (Context->getLangOpts().CPlusPlus) {
5997    // namespace std { struct __va_list {
5998    NamespaceDecl *NS;
5999    NS = NamespaceDecl::Create(const_cast<ASTContext &>(*Context),
6000                               Context->getTranslationUnitDecl(),
6001                               /*Inline*/false, SourceLocation(),
6002                               SourceLocation(), &Context->Idents.get("std"),
6003                               /*PrevDecl*/0);
6004
6005    VaListDecl = CXXRecordDecl::Create(*Context, TTK_Struct,
6006                                       Context->getTranslationUnitDecl(),
6007                                       SourceLocation(), SourceLocation(),
6008                                       &Context->Idents.get("__va_list"));
6009
6010    VaListDecl->setDeclContext(NS);
6011
6012  } else {
6013    // struct __va_list {
6014    VaListDecl = CreateRecordDecl(*Context, TTK_Struct,
6015                                  Context->getTranslationUnitDecl(),
6016                                  &Context->Idents.get("__va_list"));
6017  }
6018
6019  VaListDecl->startDefinition();
6020
6021  // void * __ap;
6022  FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6023                                       VaListDecl,
6024                                       SourceLocation(),
6025                                       SourceLocation(),
6026                                       &Context->Idents.get("__ap"),
6027                                       Context->getPointerType(Context->VoidTy),
6028                                       /*TInfo=*/0,
6029                                       /*BitWidth=*/0,
6030                                       /*Mutable=*/false,
6031                                       ICIS_NoInit);
6032  Field->setAccess(AS_public);
6033  VaListDecl->addDecl(Field);
6034
6035  // };
6036  VaListDecl->completeDefinition();
6037
6038  // typedef struct __va_list __builtin_va_list;
6039  TypeSourceInfo *TInfo
6040    = Context->getTrivialTypeSourceInfo(Context->getRecordType(VaListDecl));
6041
6042  TypedefDecl *VaListTypeDecl
6043    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
6044                          Context->getTranslationUnitDecl(),
6045                          SourceLocation(), SourceLocation(),
6046                          &Context->Idents.get("__builtin_va_list"),
6047                          TInfo);
6048
6049  return VaListTypeDecl;
6050}
6051
6052static TypedefDecl *
6053CreateSystemZBuiltinVaListDecl(const ASTContext *Context) {
6054  // typedef struct __va_list_tag {
6055  RecordDecl *VaListTagDecl;
6056  VaListTagDecl = CreateRecordDecl(*Context, TTK_Struct,
6057                                   Context->getTranslationUnitDecl(),
6058                                   &Context->Idents.get("__va_list_tag"));
6059  VaListTagDecl->startDefinition();
6060
6061  const size_t NumFields = 4;
6062  QualType FieldTypes[NumFields];
6063  const char *FieldNames[NumFields];
6064
6065  //   long __gpr;
6066  FieldTypes[0] = Context->LongTy;
6067  FieldNames[0] = "__gpr";
6068
6069  //   long __fpr;
6070  FieldTypes[1] = Context->LongTy;
6071  FieldNames[1] = "__fpr";
6072
6073  //   void *__overflow_arg_area;
6074  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
6075  FieldNames[2] = "__overflow_arg_area";
6076
6077  //   void *__reg_save_area;
6078  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
6079  FieldNames[3] = "__reg_save_area";
6080
6081  // Create fields
6082  for (unsigned i = 0; i < NumFields; ++i) {
6083    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6084                                         VaListTagDecl,
6085                                         SourceLocation(),
6086                                         SourceLocation(),
6087                                         &Context->Idents.get(FieldNames[i]),
6088                                         FieldTypes[i], /*TInfo=*/0,
6089                                         /*BitWidth=*/0,
6090                                         /*Mutable=*/false,
6091                                         ICIS_NoInit);
6092    Field->setAccess(AS_public);
6093    VaListTagDecl->addDecl(Field);
6094  }
6095  VaListTagDecl->completeDefinition();
6096  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
6097  Context->VaListTagTy = VaListTagType;
6098
6099  // } __va_list_tag;
6100  TypedefDecl *VaListTagTypedefDecl
6101    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
6102                          Context->getTranslationUnitDecl(),
6103                          SourceLocation(), SourceLocation(),
6104                          &Context->Idents.get("__va_list_tag"),
6105                          Context->getTrivialTypeSourceInfo(VaListTagType));
6106  QualType VaListTagTypedefType =
6107    Context->getTypedefType(VaListTagTypedefDecl);
6108
6109  // typedef __va_list_tag __builtin_va_list[1];
6110  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
6111  QualType VaListTagArrayType
6112    = Context->getConstantArrayType(VaListTagTypedefType,
6113                                      Size, ArrayType::Normal,0);
6114  TypeSourceInfo *TInfo
6115    = Context->getTrivialTypeSourceInfo(VaListTagArrayType);
6116  TypedefDecl *VaListTypedefDecl
6117    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
6118                          Context->getTranslationUnitDecl(),
6119                          SourceLocation(), SourceLocation(),
6120                          &Context->Idents.get("__builtin_va_list"),
6121                          TInfo);
6122
6123  return VaListTypedefDecl;
6124}
6125
6126static TypedefDecl *CreateVaListDecl(const ASTContext *Context,
6127                                     TargetInfo::BuiltinVaListKind Kind) {
6128  switch (Kind) {
6129  case TargetInfo::CharPtrBuiltinVaList:
6130    return CreateCharPtrBuiltinVaListDecl(Context);
6131  case TargetInfo::VoidPtrBuiltinVaList:
6132    return CreateVoidPtrBuiltinVaListDecl(Context);
6133  case TargetInfo::AArch64ABIBuiltinVaList:
6134    return CreateAArch64ABIBuiltinVaListDecl(Context);
6135  case TargetInfo::PowerABIBuiltinVaList:
6136    return CreatePowerABIBuiltinVaListDecl(Context);
6137  case TargetInfo::X86_64ABIBuiltinVaList:
6138    return CreateX86_64ABIBuiltinVaListDecl(Context);
6139  case TargetInfo::PNaClABIBuiltinVaList:
6140    return CreatePNaClABIBuiltinVaListDecl(Context);
6141  case TargetInfo::AAPCSABIBuiltinVaList:
6142    return CreateAAPCSABIBuiltinVaListDecl(Context);
6143  case TargetInfo::SystemZBuiltinVaList:
6144    return CreateSystemZBuiltinVaListDecl(Context);
6145  }
6146
6147  llvm_unreachable("Unhandled __builtin_va_list type kind");
6148}
6149
6150TypedefDecl *ASTContext::getBuiltinVaListDecl() const {
6151  if (!BuiltinVaListDecl)
6152    BuiltinVaListDecl = CreateVaListDecl(this, Target->getBuiltinVaListKind());
6153
6154  return BuiltinVaListDecl;
6155}
6156
6157QualType ASTContext::getVaListTagType() const {
6158  // Force the creation of VaListTagTy by building the __builtin_va_list
6159  // declaration.
6160  if (VaListTagTy.isNull())
6161    (void) getBuiltinVaListDecl();
6162
6163  return VaListTagTy;
6164}
6165
6166void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
6167  assert(ObjCConstantStringType.isNull() &&
6168         "'NSConstantString' type already set!");
6169
6170  ObjCConstantStringType = getObjCInterfaceType(Decl);
6171}
6172
6173/// \brief Retrieve the template name that corresponds to a non-empty
6174/// lookup.
6175TemplateName
6176ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
6177                                      UnresolvedSetIterator End) const {
6178  unsigned size = End - Begin;
6179  assert(size > 1 && "set is not overloaded!");
6180
6181  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
6182                          size * sizeof(FunctionTemplateDecl*));
6183  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
6184
6185  NamedDecl **Storage = OT->getStorage();
6186  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
6187    NamedDecl *D = *I;
6188    assert(isa<FunctionTemplateDecl>(D) ||
6189           (isa<UsingShadowDecl>(D) &&
6190            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
6191    *Storage++ = D;
6192  }
6193
6194  return TemplateName(OT);
6195}
6196
6197/// \brief Retrieve the template name that represents a qualified
6198/// template name such as \c std::vector.
6199TemplateName
6200ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
6201                                     bool TemplateKeyword,
6202                                     TemplateDecl *Template) const {
6203  assert(NNS && "Missing nested-name-specifier in qualified template name");
6204
6205  // FIXME: Canonicalization?
6206  llvm::FoldingSetNodeID ID;
6207  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
6208
6209  void *InsertPos = 0;
6210  QualifiedTemplateName *QTN =
6211    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6212  if (!QTN) {
6213    QTN = new (*this, llvm::alignOf<QualifiedTemplateName>())
6214        QualifiedTemplateName(NNS, TemplateKeyword, Template);
6215    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
6216  }
6217
6218  return TemplateName(QTN);
6219}
6220
6221/// \brief Retrieve the template name that represents a dependent
6222/// template name such as \c MetaFun::template apply.
6223TemplateName
6224ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
6225                                     const IdentifierInfo *Name) const {
6226  assert((!NNS || NNS->isDependent()) &&
6227         "Nested name specifier must be dependent");
6228
6229  llvm::FoldingSetNodeID ID;
6230  DependentTemplateName::Profile(ID, NNS, Name);
6231
6232  void *InsertPos = 0;
6233  DependentTemplateName *QTN =
6234    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6235
6236  if (QTN)
6237    return TemplateName(QTN);
6238
6239  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
6240  if (CanonNNS == NNS) {
6241    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6242        DependentTemplateName(NNS, Name);
6243  } else {
6244    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
6245    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6246        DependentTemplateName(NNS, Name, Canon);
6247    DependentTemplateName *CheckQTN =
6248      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6249    assert(!CheckQTN && "Dependent type name canonicalization broken");
6250    (void)CheckQTN;
6251  }
6252
6253  DependentTemplateNames.InsertNode(QTN, InsertPos);
6254  return TemplateName(QTN);
6255}
6256
6257/// \brief Retrieve the template name that represents a dependent
6258/// template name such as \c MetaFun::template operator+.
6259TemplateName
6260ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
6261                                     OverloadedOperatorKind Operator) const {
6262  assert((!NNS || NNS->isDependent()) &&
6263         "Nested name specifier must be dependent");
6264
6265  llvm::FoldingSetNodeID ID;
6266  DependentTemplateName::Profile(ID, NNS, Operator);
6267
6268  void *InsertPos = 0;
6269  DependentTemplateName *QTN
6270    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6271
6272  if (QTN)
6273    return TemplateName(QTN);
6274
6275  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
6276  if (CanonNNS == NNS) {
6277    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6278        DependentTemplateName(NNS, Operator);
6279  } else {
6280    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
6281    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6282        DependentTemplateName(NNS, Operator, Canon);
6283
6284    DependentTemplateName *CheckQTN
6285      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6286    assert(!CheckQTN && "Dependent template name canonicalization broken");
6287    (void)CheckQTN;
6288  }
6289
6290  DependentTemplateNames.InsertNode(QTN, InsertPos);
6291  return TemplateName(QTN);
6292}
6293
6294TemplateName
6295ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
6296                                         TemplateName replacement) const {
6297  llvm::FoldingSetNodeID ID;
6298  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
6299
6300  void *insertPos = 0;
6301  SubstTemplateTemplateParmStorage *subst
6302    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
6303
6304  if (!subst) {
6305    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
6306    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
6307  }
6308
6309  return TemplateName(subst);
6310}
6311
6312TemplateName
6313ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
6314                                       const TemplateArgument &ArgPack) const {
6315  ASTContext &Self = const_cast<ASTContext &>(*this);
6316  llvm::FoldingSetNodeID ID;
6317  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
6318
6319  void *InsertPos = 0;
6320  SubstTemplateTemplateParmPackStorage *Subst
6321    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
6322
6323  if (!Subst) {
6324    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
6325                                                           ArgPack.pack_size(),
6326                                                         ArgPack.pack_begin());
6327    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
6328  }
6329
6330  return TemplateName(Subst);
6331}
6332
6333/// getFromTargetType - Given one of the integer types provided by
6334/// TargetInfo, produce the corresponding type. The unsigned @p Type
6335/// is actually a value of type @c TargetInfo::IntType.
6336CanQualType ASTContext::getFromTargetType(unsigned Type) const {
6337  switch (Type) {
6338  case TargetInfo::NoInt: return CanQualType();
6339  case TargetInfo::SignedChar: return SignedCharTy;
6340  case TargetInfo::UnsignedChar: return UnsignedCharTy;
6341  case TargetInfo::SignedShort: return ShortTy;
6342  case TargetInfo::UnsignedShort: return UnsignedShortTy;
6343  case TargetInfo::SignedInt: return IntTy;
6344  case TargetInfo::UnsignedInt: return UnsignedIntTy;
6345  case TargetInfo::SignedLong: return LongTy;
6346  case TargetInfo::UnsignedLong: return UnsignedLongTy;
6347  case TargetInfo::SignedLongLong: return LongLongTy;
6348  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
6349  }
6350
6351  llvm_unreachable("Unhandled TargetInfo::IntType value");
6352}
6353
6354//===----------------------------------------------------------------------===//
6355//                        Type Predicates.
6356//===----------------------------------------------------------------------===//
6357
6358/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
6359/// garbage collection attribute.
6360///
6361Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
6362  if (getLangOpts().getGC() == LangOptions::NonGC)
6363    return Qualifiers::GCNone;
6364
6365  assert(getLangOpts().ObjC1);
6366  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
6367
6368  // Default behaviour under objective-C's gc is for ObjC pointers
6369  // (or pointers to them) be treated as though they were declared
6370  // as __strong.
6371  if (GCAttrs == Qualifiers::GCNone) {
6372    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
6373      return Qualifiers::Strong;
6374    else if (Ty->isPointerType())
6375      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
6376  } else {
6377    // It's not valid to set GC attributes on anything that isn't a
6378    // pointer.
6379#ifndef NDEBUG
6380    QualType CT = Ty->getCanonicalTypeInternal();
6381    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
6382      CT = AT->getElementType();
6383    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
6384#endif
6385  }
6386  return GCAttrs;
6387}
6388
6389//===----------------------------------------------------------------------===//
6390//                        Type Compatibility Testing
6391//===----------------------------------------------------------------------===//
6392
6393/// areCompatVectorTypes - Return true if the two specified vector types are
6394/// compatible.
6395static bool areCompatVectorTypes(const VectorType *LHS,
6396                                 const VectorType *RHS) {
6397  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
6398  return LHS->getElementType() == RHS->getElementType() &&
6399         LHS->getNumElements() == RHS->getNumElements();
6400}
6401
6402bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
6403                                          QualType SecondVec) {
6404  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
6405  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
6406
6407  if (hasSameUnqualifiedType(FirstVec, SecondVec))
6408    return true;
6409
6410  // Treat Neon vector types and most AltiVec vector types as if they are the
6411  // equivalent GCC vector types.
6412  const VectorType *First = FirstVec->getAs<VectorType>();
6413  const VectorType *Second = SecondVec->getAs<VectorType>();
6414  if (First->getNumElements() == Second->getNumElements() &&
6415      hasSameType(First->getElementType(), Second->getElementType()) &&
6416      First->getVectorKind() != VectorType::AltiVecPixel &&
6417      First->getVectorKind() != VectorType::AltiVecBool &&
6418      Second->getVectorKind() != VectorType::AltiVecPixel &&
6419      Second->getVectorKind() != VectorType::AltiVecBool)
6420    return true;
6421
6422  return false;
6423}
6424
6425//===----------------------------------------------------------------------===//
6426// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
6427//===----------------------------------------------------------------------===//
6428
6429/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
6430/// inheritance hierarchy of 'rProto'.
6431bool
6432ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
6433                                           ObjCProtocolDecl *rProto) const {
6434  if (declaresSameEntity(lProto, rProto))
6435    return true;
6436  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
6437       E = rProto->protocol_end(); PI != E; ++PI)
6438    if (ProtocolCompatibleWithProtocol(lProto, *PI))
6439      return true;
6440  return false;
6441}
6442
6443/// ObjCQualifiedClassTypesAreCompatible - compare  Class<pr,...> and
6444/// Class<pr1, ...>.
6445bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
6446                                                      QualType rhs) {
6447  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
6448  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
6449  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
6450
6451  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
6452       E = lhsQID->qual_end(); I != E; ++I) {
6453    bool match = false;
6454    ObjCProtocolDecl *lhsProto = *I;
6455    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
6456         E = rhsOPT->qual_end(); J != E; ++J) {
6457      ObjCProtocolDecl *rhsProto = *J;
6458      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
6459        match = true;
6460        break;
6461      }
6462    }
6463    if (!match)
6464      return false;
6465  }
6466  return true;
6467}
6468
6469/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
6470/// ObjCQualifiedIDType.
6471bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
6472                                                   bool compare) {
6473  // Allow id<P..> and an 'id' or void* type in all cases.
6474  if (lhs->isVoidPointerType() ||
6475      lhs->isObjCIdType() || lhs->isObjCClassType())
6476    return true;
6477  else if (rhs->isVoidPointerType() ||
6478           rhs->isObjCIdType() || rhs->isObjCClassType())
6479    return true;
6480
6481  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
6482    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
6483
6484    if (!rhsOPT) return false;
6485
6486    if (rhsOPT->qual_empty()) {
6487      // If the RHS is a unqualified interface pointer "NSString*",
6488      // make sure we check the class hierarchy.
6489      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
6490        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
6491             E = lhsQID->qual_end(); I != E; ++I) {
6492          // when comparing an id<P> on lhs with a static type on rhs,
6493          // see if static class implements all of id's protocols, directly or
6494          // through its super class and categories.
6495          if (!rhsID->ClassImplementsProtocol(*I, true))
6496            return false;
6497        }
6498      }
6499      // If there are no qualifiers and no interface, we have an 'id'.
6500      return true;
6501    }
6502    // Both the right and left sides have qualifiers.
6503    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
6504         E = lhsQID->qual_end(); I != E; ++I) {
6505      ObjCProtocolDecl *lhsProto = *I;
6506      bool match = false;
6507
6508      // when comparing an id<P> on lhs with a static type on rhs,
6509      // see if static class implements all of id's protocols, directly or
6510      // through its super class and categories.
6511      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
6512           E = rhsOPT->qual_end(); J != E; ++J) {
6513        ObjCProtocolDecl *rhsProto = *J;
6514        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6515            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6516          match = true;
6517          break;
6518        }
6519      }
6520      // If the RHS is a qualified interface pointer "NSString<P>*",
6521      // make sure we check the class hierarchy.
6522      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
6523        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
6524             E = lhsQID->qual_end(); I != E; ++I) {
6525          // when comparing an id<P> on lhs with a static type on rhs,
6526          // see if static class implements all of id's protocols, directly or
6527          // through its super class and categories.
6528          if (rhsID->ClassImplementsProtocol(*I, true)) {
6529            match = true;
6530            break;
6531          }
6532        }
6533      }
6534      if (!match)
6535        return false;
6536    }
6537
6538    return true;
6539  }
6540
6541  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
6542  assert(rhsQID && "One of the LHS/RHS should be id<x>");
6543
6544  if (const ObjCObjectPointerType *lhsOPT =
6545        lhs->getAsObjCInterfacePointerType()) {
6546    // If both the right and left sides have qualifiers.
6547    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
6548         E = lhsOPT->qual_end(); I != E; ++I) {
6549      ObjCProtocolDecl *lhsProto = *I;
6550      bool match = false;
6551
6552      // when comparing an id<P> on rhs with a static type on lhs,
6553      // see if static class implements all of id's protocols, directly or
6554      // through its super class and categories.
6555      // First, lhs protocols in the qualifier list must be found, direct
6556      // or indirect in rhs's qualifier list or it is a mismatch.
6557      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
6558           E = rhsQID->qual_end(); J != E; ++J) {
6559        ObjCProtocolDecl *rhsProto = *J;
6560        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6561            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6562          match = true;
6563          break;
6564        }
6565      }
6566      if (!match)
6567        return false;
6568    }
6569
6570    // Static class's protocols, or its super class or category protocols
6571    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
6572    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
6573      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
6574      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
6575      // This is rather dubious but matches gcc's behavior. If lhs has
6576      // no type qualifier and its class has no static protocol(s)
6577      // assume that it is mismatch.
6578      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
6579        return false;
6580      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
6581           LHSInheritedProtocols.begin(),
6582           E = LHSInheritedProtocols.end(); I != E; ++I) {
6583        bool match = false;
6584        ObjCProtocolDecl *lhsProto = (*I);
6585        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
6586             E = rhsQID->qual_end(); J != E; ++J) {
6587          ObjCProtocolDecl *rhsProto = *J;
6588          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6589              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6590            match = true;
6591            break;
6592          }
6593        }
6594        if (!match)
6595          return false;
6596      }
6597    }
6598    return true;
6599  }
6600  return false;
6601}
6602
6603/// canAssignObjCInterfaces - Return true if the two interface types are
6604/// compatible for assignment from RHS to LHS.  This handles validation of any
6605/// protocol qualifiers on the LHS or RHS.
6606///
6607bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
6608                                         const ObjCObjectPointerType *RHSOPT) {
6609  const ObjCObjectType* LHS = LHSOPT->getObjectType();
6610  const ObjCObjectType* RHS = RHSOPT->getObjectType();
6611
6612  // If either type represents the built-in 'id' or 'Class' types, return true.
6613  if (LHS->isObjCUnqualifiedIdOrClass() ||
6614      RHS->isObjCUnqualifiedIdOrClass())
6615    return true;
6616
6617  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
6618    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
6619                                             QualType(RHSOPT,0),
6620                                             false);
6621
6622  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
6623    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
6624                                                QualType(RHSOPT,0));
6625
6626  // If we have 2 user-defined types, fall into that path.
6627  if (LHS->getInterface() && RHS->getInterface())
6628    return canAssignObjCInterfaces(LHS, RHS);
6629
6630  return false;
6631}
6632
6633/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
6634/// for providing type-safety for objective-c pointers used to pass/return
6635/// arguments in block literals. When passed as arguments, passing 'A*' where
6636/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
6637/// not OK. For the return type, the opposite is not OK.
6638bool ASTContext::canAssignObjCInterfacesInBlockPointer(
6639                                         const ObjCObjectPointerType *LHSOPT,
6640                                         const ObjCObjectPointerType *RHSOPT,
6641                                         bool BlockReturnType) {
6642  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
6643    return true;
6644
6645  if (LHSOPT->isObjCBuiltinType()) {
6646    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
6647  }
6648
6649  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
6650    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
6651                                             QualType(RHSOPT,0),
6652                                             false);
6653
6654  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
6655  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
6656  if (LHS && RHS)  { // We have 2 user-defined types.
6657    if (LHS != RHS) {
6658      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
6659        return BlockReturnType;
6660      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
6661        return !BlockReturnType;
6662    }
6663    else
6664      return true;
6665  }
6666  return false;
6667}
6668
6669/// getIntersectionOfProtocols - This routine finds the intersection of set
6670/// of protocols inherited from two distinct objective-c pointer objects.
6671/// It is used to build composite qualifier list of the composite type of
6672/// the conditional expression involving two objective-c pointer objects.
6673static
6674void getIntersectionOfProtocols(ASTContext &Context,
6675                                const ObjCObjectPointerType *LHSOPT,
6676                                const ObjCObjectPointerType *RHSOPT,
6677      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
6678
6679  const ObjCObjectType* LHS = LHSOPT->getObjectType();
6680  const ObjCObjectType* RHS = RHSOPT->getObjectType();
6681  assert(LHS->getInterface() && "LHS must have an interface base");
6682  assert(RHS->getInterface() && "RHS must have an interface base");
6683
6684  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
6685  unsigned LHSNumProtocols = LHS->getNumProtocols();
6686  if (LHSNumProtocols > 0)
6687    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
6688  else {
6689    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
6690    Context.CollectInheritedProtocols(LHS->getInterface(),
6691                                      LHSInheritedProtocols);
6692    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
6693                                LHSInheritedProtocols.end());
6694  }
6695
6696  unsigned RHSNumProtocols = RHS->getNumProtocols();
6697  if (RHSNumProtocols > 0) {
6698    ObjCProtocolDecl **RHSProtocols =
6699      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
6700    for (unsigned i = 0; i < RHSNumProtocols; ++i)
6701      if (InheritedProtocolSet.count(RHSProtocols[i]))
6702        IntersectionOfProtocols.push_back(RHSProtocols[i]);
6703  } else {
6704    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
6705    Context.CollectInheritedProtocols(RHS->getInterface(),
6706                                      RHSInheritedProtocols);
6707    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
6708         RHSInheritedProtocols.begin(),
6709         E = RHSInheritedProtocols.end(); I != E; ++I)
6710      if (InheritedProtocolSet.count((*I)))
6711        IntersectionOfProtocols.push_back((*I));
6712  }
6713}
6714
6715/// areCommonBaseCompatible - Returns common base class of the two classes if
6716/// one found. Note that this is O'2 algorithm. But it will be called as the
6717/// last type comparison in a ?-exp of ObjC pointer types before a
6718/// warning is issued. So, its invokation is extremely rare.
6719QualType ASTContext::areCommonBaseCompatible(
6720                                          const ObjCObjectPointerType *Lptr,
6721                                          const ObjCObjectPointerType *Rptr) {
6722  const ObjCObjectType *LHS = Lptr->getObjectType();
6723  const ObjCObjectType *RHS = Rptr->getObjectType();
6724  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
6725  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
6726  if (!LDecl || !RDecl || (declaresSameEntity(LDecl, RDecl)))
6727    return QualType();
6728
6729  do {
6730    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
6731    if (canAssignObjCInterfaces(LHS, RHS)) {
6732      SmallVector<ObjCProtocolDecl *, 8> Protocols;
6733      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
6734
6735      QualType Result = QualType(LHS, 0);
6736      if (!Protocols.empty())
6737        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
6738      Result = getObjCObjectPointerType(Result);
6739      return Result;
6740    }
6741  } while ((LDecl = LDecl->getSuperClass()));
6742
6743  return QualType();
6744}
6745
6746bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
6747                                         const ObjCObjectType *RHS) {
6748  assert(LHS->getInterface() && "LHS is not an interface type");
6749  assert(RHS->getInterface() && "RHS is not an interface type");
6750
6751  // Verify that the base decls are compatible: the RHS must be a subclass of
6752  // the LHS.
6753  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
6754    return false;
6755
6756  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
6757  // protocol qualified at all, then we are good.
6758  if (LHS->getNumProtocols() == 0)
6759    return true;
6760
6761  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't,
6762  // more detailed analysis is required.
6763  if (RHS->getNumProtocols() == 0) {
6764    // OK, if LHS is a superclass of RHS *and*
6765    // this superclass is assignment compatible with LHS.
6766    // false otherwise.
6767    bool IsSuperClass =
6768      LHS->getInterface()->isSuperClassOf(RHS->getInterface());
6769    if (IsSuperClass) {
6770      // OK if conversion of LHS to SuperClass results in narrowing of types
6771      // ; i.e., SuperClass may implement at least one of the protocols
6772      // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
6773      // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
6774      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
6775      CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
6776      // If super class has no protocols, it is not a match.
6777      if (SuperClassInheritedProtocols.empty())
6778        return false;
6779
6780      for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
6781           LHSPE = LHS->qual_end();
6782           LHSPI != LHSPE; LHSPI++) {
6783        bool SuperImplementsProtocol = false;
6784        ObjCProtocolDecl *LHSProto = (*LHSPI);
6785
6786        for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
6787             SuperClassInheritedProtocols.begin(),
6788             E = SuperClassInheritedProtocols.end(); I != E; ++I) {
6789          ObjCProtocolDecl *SuperClassProto = (*I);
6790          if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
6791            SuperImplementsProtocol = true;
6792            break;
6793          }
6794        }
6795        if (!SuperImplementsProtocol)
6796          return false;
6797      }
6798      return true;
6799    }
6800    return false;
6801  }
6802
6803  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
6804                                     LHSPE = LHS->qual_end();
6805       LHSPI != LHSPE; LHSPI++) {
6806    bool RHSImplementsProtocol = false;
6807
6808    // If the RHS doesn't implement the protocol on the left, the types
6809    // are incompatible.
6810    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
6811                                       RHSPE = RHS->qual_end();
6812         RHSPI != RHSPE; RHSPI++) {
6813      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
6814        RHSImplementsProtocol = true;
6815        break;
6816      }
6817    }
6818    // FIXME: For better diagnostics, consider passing back the protocol name.
6819    if (!RHSImplementsProtocol)
6820      return false;
6821  }
6822  // The RHS implements all protocols listed on the LHS.
6823  return true;
6824}
6825
6826bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
6827  // get the "pointed to" types
6828  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
6829  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
6830
6831  if (!LHSOPT || !RHSOPT)
6832    return false;
6833
6834  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
6835         canAssignObjCInterfaces(RHSOPT, LHSOPT);
6836}
6837
6838bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
6839  return canAssignObjCInterfaces(
6840                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
6841                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
6842}
6843
6844/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
6845/// both shall have the identically qualified version of a compatible type.
6846/// C99 6.2.7p1: Two types have compatible types if their types are the
6847/// same. See 6.7.[2,3,5] for additional rules.
6848bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
6849                                    bool CompareUnqualified) {
6850  if (getLangOpts().CPlusPlus)
6851    return hasSameType(LHS, RHS);
6852
6853  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
6854}
6855
6856bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
6857  return typesAreCompatible(LHS, RHS);
6858}
6859
6860bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
6861  return !mergeTypes(LHS, RHS, true).isNull();
6862}
6863
6864/// mergeTransparentUnionType - if T is a transparent union type and a member
6865/// of T is compatible with SubType, return the merged type, else return
6866/// QualType()
6867QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
6868                                               bool OfBlockPointer,
6869                                               bool Unqualified) {
6870  if (const RecordType *UT = T->getAsUnionType()) {
6871    RecordDecl *UD = UT->getDecl();
6872    if (UD->hasAttr<TransparentUnionAttr>()) {
6873      for (RecordDecl::field_iterator it = UD->field_begin(),
6874           itend = UD->field_end(); it != itend; ++it) {
6875        QualType ET = it->getType().getUnqualifiedType();
6876        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
6877        if (!MT.isNull())
6878          return MT;
6879      }
6880    }
6881  }
6882
6883  return QualType();
6884}
6885
6886/// mergeFunctionArgumentTypes - merge two types which appear as function
6887/// argument types
6888QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
6889                                                bool OfBlockPointer,
6890                                                bool Unqualified) {
6891  // GNU extension: two types are compatible if they appear as a function
6892  // argument, one of the types is a transparent union type and the other
6893  // type is compatible with a union member
6894  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
6895                                              Unqualified);
6896  if (!lmerge.isNull())
6897    return lmerge;
6898
6899  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
6900                                              Unqualified);
6901  if (!rmerge.isNull())
6902    return rmerge;
6903
6904  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
6905}
6906
6907QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
6908                                        bool OfBlockPointer,
6909                                        bool Unqualified) {
6910  const FunctionType *lbase = lhs->getAs<FunctionType>();
6911  const FunctionType *rbase = rhs->getAs<FunctionType>();
6912  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
6913  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
6914  bool allLTypes = true;
6915  bool allRTypes = true;
6916
6917  // Check return type
6918  QualType retType;
6919  if (OfBlockPointer) {
6920    QualType RHS = rbase->getResultType();
6921    QualType LHS = lbase->getResultType();
6922    bool UnqualifiedResult = Unqualified;
6923    if (!UnqualifiedResult)
6924      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
6925    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
6926  }
6927  else
6928    retType = mergeTypes(lbase->getResultType(), rbase->getResultType(), false,
6929                         Unqualified);
6930  if (retType.isNull()) return QualType();
6931
6932  if (Unqualified)
6933    retType = retType.getUnqualifiedType();
6934
6935  CanQualType LRetType = getCanonicalType(lbase->getResultType());
6936  CanQualType RRetType = getCanonicalType(rbase->getResultType());
6937  if (Unqualified) {
6938    LRetType = LRetType.getUnqualifiedType();
6939    RRetType = RRetType.getUnqualifiedType();
6940  }
6941
6942  if (getCanonicalType(retType) != LRetType)
6943    allLTypes = false;
6944  if (getCanonicalType(retType) != RRetType)
6945    allRTypes = false;
6946
6947  // FIXME: double check this
6948  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
6949  //                           rbase->getRegParmAttr() != 0 &&
6950  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
6951  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
6952  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
6953
6954  // Compatible functions must have compatible calling conventions
6955  if (lbaseInfo.getCC() != rbaseInfo.getCC())
6956    return QualType();
6957
6958  // Regparm is part of the calling convention.
6959  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
6960    return QualType();
6961  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
6962    return QualType();
6963
6964  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
6965    return QualType();
6966
6967  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
6968  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
6969
6970  if (lbaseInfo.getNoReturn() != NoReturn)
6971    allLTypes = false;
6972  if (rbaseInfo.getNoReturn() != NoReturn)
6973    allRTypes = false;
6974
6975  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
6976
6977  if (lproto && rproto) { // two C99 style function prototypes
6978    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
6979           "C++ shouldn't be here");
6980    unsigned lproto_nargs = lproto->getNumArgs();
6981    unsigned rproto_nargs = rproto->getNumArgs();
6982
6983    // Compatible functions must have the same number of arguments
6984    if (lproto_nargs != rproto_nargs)
6985      return QualType();
6986
6987    // Variadic and non-variadic functions aren't compatible
6988    if (lproto->isVariadic() != rproto->isVariadic())
6989      return QualType();
6990
6991    if (lproto->getTypeQuals() != rproto->getTypeQuals())
6992      return QualType();
6993
6994    if (LangOpts.ObjCAutoRefCount &&
6995        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
6996      return QualType();
6997
6998    // Check argument compatibility
6999    SmallVector<QualType, 10> types;
7000    for (unsigned i = 0; i < lproto_nargs; i++) {
7001      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
7002      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
7003      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
7004                                                    OfBlockPointer,
7005                                                    Unqualified);
7006      if (argtype.isNull()) return QualType();
7007
7008      if (Unqualified)
7009        argtype = argtype.getUnqualifiedType();
7010
7011      types.push_back(argtype);
7012      if (Unqualified) {
7013        largtype = largtype.getUnqualifiedType();
7014        rargtype = rargtype.getUnqualifiedType();
7015      }
7016
7017      if (getCanonicalType(argtype) != getCanonicalType(largtype))
7018        allLTypes = false;
7019      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
7020        allRTypes = false;
7021    }
7022
7023    if (allLTypes) return lhs;
7024    if (allRTypes) return rhs;
7025
7026    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
7027    EPI.ExtInfo = einfo;
7028    return getFunctionType(retType, types, EPI);
7029  }
7030
7031  if (lproto) allRTypes = false;
7032  if (rproto) allLTypes = false;
7033
7034  const FunctionProtoType *proto = lproto ? lproto : rproto;
7035  if (proto) {
7036    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
7037    if (proto->isVariadic()) return QualType();
7038    // Check that the types are compatible with the types that
7039    // would result from default argument promotions (C99 6.7.5.3p15).
7040    // The only types actually affected are promotable integer
7041    // types and floats, which would be passed as a different
7042    // type depending on whether the prototype is visible.
7043    unsigned proto_nargs = proto->getNumArgs();
7044    for (unsigned i = 0; i < proto_nargs; ++i) {
7045      QualType argTy = proto->getArgType(i);
7046
7047      // Look at the converted type of enum types, since that is the type used
7048      // to pass enum values.
7049      if (const EnumType *Enum = argTy->getAs<EnumType>()) {
7050        argTy = Enum->getDecl()->getIntegerType();
7051        if (argTy.isNull())
7052          return QualType();
7053      }
7054
7055      if (argTy->isPromotableIntegerType() ||
7056          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
7057        return QualType();
7058    }
7059
7060    if (allLTypes) return lhs;
7061    if (allRTypes) return rhs;
7062
7063    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
7064    EPI.ExtInfo = einfo;
7065    return getFunctionType(retType, proto->getArgTypes(), EPI);
7066  }
7067
7068  if (allLTypes) return lhs;
7069  if (allRTypes) return rhs;
7070  return getFunctionNoProtoType(retType, einfo);
7071}
7072
7073/// Given that we have an enum type and a non-enum type, try to merge them.
7074static QualType mergeEnumWithInteger(ASTContext &Context, const EnumType *ET,
7075                                     QualType other, bool isBlockReturnType) {
7076  // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
7077  // a signed integer type, or an unsigned integer type.
7078  // Compatibility is based on the underlying type, not the promotion
7079  // type.
7080  QualType underlyingType = ET->getDecl()->getIntegerType();
7081  if (underlyingType.isNull()) return QualType();
7082  if (Context.hasSameType(underlyingType, other))
7083    return other;
7084
7085  // In block return types, we're more permissive and accept any
7086  // integral type of the same size.
7087  if (isBlockReturnType && other->isIntegerType() &&
7088      Context.getTypeSize(underlyingType) == Context.getTypeSize(other))
7089    return other;
7090
7091  return QualType();
7092}
7093
7094QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
7095                                bool OfBlockPointer,
7096                                bool Unqualified, bool BlockReturnType) {
7097  // C++ [expr]: If an expression initially has the type "reference to T", the
7098  // type is adjusted to "T" prior to any further analysis, the expression
7099  // designates the object or function denoted by the reference, and the
7100  // expression is an lvalue unless the reference is an rvalue reference and
7101  // the expression is a function call (possibly inside parentheses).
7102  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
7103  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
7104
7105  if (Unqualified) {
7106    LHS = LHS.getUnqualifiedType();
7107    RHS = RHS.getUnqualifiedType();
7108  }
7109
7110  QualType LHSCan = getCanonicalType(LHS),
7111           RHSCan = getCanonicalType(RHS);
7112
7113  // If two types are identical, they are compatible.
7114  if (LHSCan == RHSCan)
7115    return LHS;
7116
7117  // If the qualifiers are different, the types aren't compatible... mostly.
7118  Qualifiers LQuals = LHSCan.getLocalQualifiers();
7119  Qualifiers RQuals = RHSCan.getLocalQualifiers();
7120  if (LQuals != RQuals) {
7121    // If any of these qualifiers are different, we have a type
7122    // mismatch.
7123    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
7124        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
7125        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
7126      return QualType();
7127
7128    // Exactly one GC qualifier difference is allowed: __strong is
7129    // okay if the other type has no GC qualifier but is an Objective
7130    // C object pointer (i.e. implicitly strong by default).  We fix
7131    // this by pretending that the unqualified type was actually
7132    // qualified __strong.
7133    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
7134    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
7135    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
7136
7137    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
7138      return QualType();
7139
7140    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
7141      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
7142    }
7143    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
7144      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
7145    }
7146    return QualType();
7147  }
7148
7149  // Okay, qualifiers are equal.
7150
7151  Type::TypeClass LHSClass = LHSCan->getTypeClass();
7152  Type::TypeClass RHSClass = RHSCan->getTypeClass();
7153
7154  // We want to consider the two function types to be the same for these
7155  // comparisons, just force one to the other.
7156  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
7157  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
7158
7159  // Same as above for arrays
7160  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
7161    LHSClass = Type::ConstantArray;
7162  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
7163    RHSClass = Type::ConstantArray;
7164
7165  // ObjCInterfaces are just specialized ObjCObjects.
7166  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
7167  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
7168
7169  // Canonicalize ExtVector -> Vector.
7170  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
7171  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
7172
7173  // If the canonical type classes don't match.
7174  if (LHSClass != RHSClass) {
7175    // Note that we only have special rules for turning block enum
7176    // returns into block int returns, not vice-versa.
7177    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
7178      return mergeEnumWithInteger(*this, ETy, RHS, false);
7179    }
7180    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
7181      return mergeEnumWithInteger(*this, ETy, LHS, BlockReturnType);
7182    }
7183    // allow block pointer type to match an 'id' type.
7184    if (OfBlockPointer && !BlockReturnType) {
7185       if (LHS->isObjCIdType() && RHS->isBlockPointerType())
7186         return LHS;
7187      if (RHS->isObjCIdType() && LHS->isBlockPointerType())
7188        return RHS;
7189    }
7190
7191    return QualType();
7192  }
7193
7194  // The canonical type classes match.
7195  switch (LHSClass) {
7196#define TYPE(Class, Base)
7197#define ABSTRACT_TYPE(Class, Base)
7198#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
7199#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
7200#define DEPENDENT_TYPE(Class, Base) case Type::Class:
7201#include "clang/AST/TypeNodes.def"
7202    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
7203
7204  case Type::Auto:
7205  case Type::LValueReference:
7206  case Type::RValueReference:
7207  case Type::MemberPointer:
7208    llvm_unreachable("C++ should never be in mergeTypes");
7209
7210  case Type::ObjCInterface:
7211  case Type::IncompleteArray:
7212  case Type::VariableArray:
7213  case Type::FunctionProto:
7214  case Type::ExtVector:
7215    llvm_unreachable("Types are eliminated above");
7216
7217  case Type::Pointer:
7218  {
7219    // Merge two pointer types, while trying to preserve typedef info
7220    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
7221    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
7222    if (Unqualified) {
7223      LHSPointee = LHSPointee.getUnqualifiedType();
7224      RHSPointee = RHSPointee.getUnqualifiedType();
7225    }
7226    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
7227                                     Unqualified);
7228    if (ResultType.isNull()) return QualType();
7229    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
7230      return LHS;
7231    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
7232      return RHS;
7233    return getPointerType(ResultType);
7234  }
7235  case Type::BlockPointer:
7236  {
7237    // Merge two block pointer types, while trying to preserve typedef info
7238    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
7239    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
7240    if (Unqualified) {
7241      LHSPointee = LHSPointee.getUnqualifiedType();
7242      RHSPointee = RHSPointee.getUnqualifiedType();
7243    }
7244    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
7245                                     Unqualified);
7246    if (ResultType.isNull()) return QualType();
7247    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
7248      return LHS;
7249    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
7250      return RHS;
7251    return getBlockPointerType(ResultType);
7252  }
7253  case Type::Atomic:
7254  {
7255    // Merge two pointer types, while trying to preserve typedef info
7256    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
7257    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
7258    if (Unqualified) {
7259      LHSValue = LHSValue.getUnqualifiedType();
7260      RHSValue = RHSValue.getUnqualifiedType();
7261    }
7262    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
7263                                     Unqualified);
7264    if (ResultType.isNull()) return QualType();
7265    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
7266      return LHS;
7267    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
7268      return RHS;
7269    return getAtomicType(ResultType);
7270  }
7271  case Type::ConstantArray:
7272  {
7273    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
7274    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
7275    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
7276      return QualType();
7277
7278    QualType LHSElem = getAsArrayType(LHS)->getElementType();
7279    QualType RHSElem = getAsArrayType(RHS)->getElementType();
7280    if (Unqualified) {
7281      LHSElem = LHSElem.getUnqualifiedType();
7282      RHSElem = RHSElem.getUnqualifiedType();
7283    }
7284
7285    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
7286    if (ResultType.isNull()) return QualType();
7287    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
7288      return LHS;
7289    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
7290      return RHS;
7291    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
7292                                          ArrayType::ArraySizeModifier(), 0);
7293    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
7294                                          ArrayType::ArraySizeModifier(), 0);
7295    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
7296    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
7297    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
7298      return LHS;
7299    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
7300      return RHS;
7301    if (LVAT) {
7302      // FIXME: This isn't correct! But tricky to implement because
7303      // the array's size has to be the size of LHS, but the type
7304      // has to be different.
7305      return LHS;
7306    }
7307    if (RVAT) {
7308      // FIXME: This isn't correct! But tricky to implement because
7309      // the array's size has to be the size of RHS, but the type
7310      // has to be different.
7311      return RHS;
7312    }
7313    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
7314    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
7315    return getIncompleteArrayType(ResultType,
7316                                  ArrayType::ArraySizeModifier(), 0);
7317  }
7318  case Type::FunctionNoProto:
7319    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
7320  case Type::Record:
7321  case Type::Enum:
7322    return QualType();
7323  case Type::Builtin:
7324    // Only exactly equal builtin types are compatible, which is tested above.
7325    return QualType();
7326  case Type::Complex:
7327    // Distinct complex types are incompatible.
7328    return QualType();
7329  case Type::Vector:
7330    // FIXME: The merged type should be an ExtVector!
7331    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
7332                             RHSCan->getAs<VectorType>()))
7333      return LHS;
7334    return QualType();
7335  case Type::ObjCObject: {
7336    // Check if the types are assignment compatible.
7337    // FIXME: This should be type compatibility, e.g. whether
7338    // "LHS x; RHS x;" at global scope is legal.
7339    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
7340    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
7341    if (canAssignObjCInterfaces(LHSIface, RHSIface))
7342      return LHS;
7343
7344    return QualType();
7345  }
7346  case Type::ObjCObjectPointer: {
7347    if (OfBlockPointer) {
7348      if (canAssignObjCInterfacesInBlockPointer(
7349                                          LHS->getAs<ObjCObjectPointerType>(),
7350                                          RHS->getAs<ObjCObjectPointerType>(),
7351                                          BlockReturnType))
7352        return LHS;
7353      return QualType();
7354    }
7355    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
7356                                RHS->getAs<ObjCObjectPointerType>()))
7357      return LHS;
7358
7359    return QualType();
7360  }
7361  }
7362
7363  llvm_unreachable("Invalid Type::Class!");
7364}
7365
7366bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
7367                   const FunctionProtoType *FromFunctionType,
7368                   const FunctionProtoType *ToFunctionType) {
7369  if (FromFunctionType->hasAnyConsumedArgs() !=
7370      ToFunctionType->hasAnyConsumedArgs())
7371    return false;
7372  FunctionProtoType::ExtProtoInfo FromEPI =
7373    FromFunctionType->getExtProtoInfo();
7374  FunctionProtoType::ExtProtoInfo ToEPI =
7375    ToFunctionType->getExtProtoInfo();
7376  if (FromEPI.ConsumedArguments && ToEPI.ConsumedArguments)
7377    for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs();
7378         ArgIdx != NumArgs; ++ArgIdx)  {
7379      if (FromEPI.ConsumedArguments[ArgIdx] !=
7380          ToEPI.ConsumedArguments[ArgIdx])
7381        return false;
7382    }
7383  return true;
7384}
7385
7386/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
7387/// 'RHS' attributes and returns the merged version; including for function
7388/// return types.
7389QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
7390  QualType LHSCan = getCanonicalType(LHS),
7391  RHSCan = getCanonicalType(RHS);
7392  // If two types are identical, they are compatible.
7393  if (LHSCan == RHSCan)
7394    return LHS;
7395  if (RHSCan->isFunctionType()) {
7396    if (!LHSCan->isFunctionType())
7397      return QualType();
7398    QualType OldReturnType =
7399      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
7400    QualType NewReturnType =
7401      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
7402    QualType ResReturnType =
7403      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
7404    if (ResReturnType.isNull())
7405      return QualType();
7406    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
7407      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
7408      // In either case, use OldReturnType to build the new function type.
7409      const FunctionType *F = LHS->getAs<FunctionType>();
7410      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
7411        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
7412        EPI.ExtInfo = getFunctionExtInfo(LHS);
7413        QualType ResultType =
7414            getFunctionType(OldReturnType, FPT->getArgTypes(), EPI);
7415        return ResultType;
7416      }
7417    }
7418    return QualType();
7419  }
7420
7421  // If the qualifiers are different, the types can still be merged.
7422  Qualifiers LQuals = LHSCan.getLocalQualifiers();
7423  Qualifiers RQuals = RHSCan.getLocalQualifiers();
7424  if (LQuals != RQuals) {
7425    // If any of these qualifiers are different, we have a type mismatch.
7426    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
7427        LQuals.getAddressSpace() != RQuals.getAddressSpace())
7428      return QualType();
7429
7430    // Exactly one GC qualifier difference is allowed: __strong is
7431    // okay if the other type has no GC qualifier but is an Objective
7432    // C object pointer (i.e. implicitly strong by default).  We fix
7433    // this by pretending that the unqualified type was actually
7434    // qualified __strong.
7435    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
7436    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
7437    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
7438
7439    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
7440      return QualType();
7441
7442    if (GC_L == Qualifiers::Strong)
7443      return LHS;
7444    if (GC_R == Qualifiers::Strong)
7445      return RHS;
7446    return QualType();
7447  }
7448
7449  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
7450    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
7451    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
7452    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
7453    if (ResQT == LHSBaseQT)
7454      return LHS;
7455    if (ResQT == RHSBaseQT)
7456      return RHS;
7457  }
7458  return QualType();
7459}
7460
7461//===----------------------------------------------------------------------===//
7462//                         Integer Predicates
7463//===----------------------------------------------------------------------===//
7464
7465unsigned ASTContext::getIntWidth(QualType T) const {
7466  if (const EnumType *ET = dyn_cast<EnumType>(T))
7467    T = ET->getDecl()->getIntegerType();
7468  if (T->isBooleanType())
7469    return 1;
7470  // For builtin types, just use the standard type sizing method
7471  return (unsigned)getTypeSize(T);
7472}
7473
7474QualType ASTContext::getCorrespondingUnsignedType(QualType T) const {
7475  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
7476
7477  // Turn <4 x signed int> -> <4 x unsigned int>
7478  if (const VectorType *VTy = T->getAs<VectorType>())
7479    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
7480                         VTy->getNumElements(), VTy->getVectorKind());
7481
7482  // For enums, we return the unsigned version of the base type.
7483  if (const EnumType *ETy = T->getAs<EnumType>())
7484    T = ETy->getDecl()->getIntegerType();
7485
7486  const BuiltinType *BTy = T->getAs<BuiltinType>();
7487  assert(BTy && "Unexpected signed integer type");
7488  switch (BTy->getKind()) {
7489  case BuiltinType::Char_S:
7490  case BuiltinType::SChar:
7491    return UnsignedCharTy;
7492  case BuiltinType::Short:
7493    return UnsignedShortTy;
7494  case BuiltinType::Int:
7495    return UnsignedIntTy;
7496  case BuiltinType::Long:
7497    return UnsignedLongTy;
7498  case BuiltinType::LongLong:
7499    return UnsignedLongLongTy;
7500  case BuiltinType::Int128:
7501    return UnsignedInt128Ty;
7502  default:
7503    llvm_unreachable("Unexpected signed integer type");
7504  }
7505}
7506
7507ASTMutationListener::~ASTMutationListener() { }
7508
7509void ASTMutationListener::DeducedReturnType(const FunctionDecl *FD,
7510                                            QualType ReturnType) {}
7511
7512//===----------------------------------------------------------------------===//
7513//                          Builtin Type Computation
7514//===----------------------------------------------------------------------===//
7515
7516/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
7517/// pointer over the consumed characters.  This returns the resultant type.  If
7518/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
7519/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
7520/// a vector of "i*".
7521///
7522/// RequiresICE is filled in on return to indicate whether the value is required
7523/// to be an Integer Constant Expression.
7524static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
7525                                  ASTContext::GetBuiltinTypeError &Error,
7526                                  bool &RequiresICE,
7527                                  bool AllowTypeModifiers) {
7528  // Modifiers.
7529  int HowLong = 0;
7530  bool Signed = false, Unsigned = false;
7531  RequiresICE = false;
7532
7533  // Read the prefixed modifiers first.
7534  bool Done = false;
7535  while (!Done) {
7536    switch (*Str++) {
7537    default: Done = true; --Str; break;
7538    case 'I':
7539      RequiresICE = true;
7540      break;
7541    case 'S':
7542      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
7543      assert(!Signed && "Can't use 'S' modifier multiple times!");
7544      Signed = true;
7545      break;
7546    case 'U':
7547      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
7548      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
7549      Unsigned = true;
7550      break;
7551    case 'L':
7552      assert(HowLong <= 2 && "Can't have LLLL modifier");
7553      ++HowLong;
7554      break;
7555    }
7556  }
7557
7558  QualType Type;
7559
7560  // Read the base type.
7561  switch (*Str++) {
7562  default: llvm_unreachable("Unknown builtin type letter!");
7563  case 'v':
7564    assert(HowLong == 0 && !Signed && !Unsigned &&
7565           "Bad modifiers used with 'v'!");
7566    Type = Context.VoidTy;
7567    break;
7568  case 'h':
7569    assert(HowLong == 0 && !Signed && !Unsigned &&
7570           "Bad modifiers used with 'f'!");
7571    Type = Context.HalfTy;
7572    break;
7573  case 'f':
7574    assert(HowLong == 0 && !Signed && !Unsigned &&
7575           "Bad modifiers used with 'f'!");
7576    Type = Context.FloatTy;
7577    break;
7578  case 'd':
7579    assert(HowLong < 2 && !Signed && !Unsigned &&
7580           "Bad modifiers used with 'd'!");
7581    if (HowLong)
7582      Type = Context.LongDoubleTy;
7583    else
7584      Type = Context.DoubleTy;
7585    break;
7586  case 's':
7587    assert(HowLong == 0 && "Bad modifiers used with 's'!");
7588    if (Unsigned)
7589      Type = Context.UnsignedShortTy;
7590    else
7591      Type = Context.ShortTy;
7592    break;
7593  case 'i':
7594    if (HowLong == 3)
7595      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
7596    else if (HowLong == 2)
7597      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
7598    else if (HowLong == 1)
7599      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
7600    else
7601      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
7602    break;
7603  case 'c':
7604    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
7605    if (Signed)
7606      Type = Context.SignedCharTy;
7607    else if (Unsigned)
7608      Type = Context.UnsignedCharTy;
7609    else
7610      Type = Context.CharTy;
7611    break;
7612  case 'b': // boolean
7613    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
7614    Type = Context.BoolTy;
7615    break;
7616  case 'z':  // size_t.
7617    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
7618    Type = Context.getSizeType();
7619    break;
7620  case 'F':
7621    Type = Context.getCFConstantStringType();
7622    break;
7623  case 'G':
7624    Type = Context.getObjCIdType();
7625    break;
7626  case 'H':
7627    Type = Context.getObjCSelType();
7628    break;
7629  case 'M':
7630    Type = Context.getObjCSuperType();
7631    break;
7632  case 'a':
7633    Type = Context.getBuiltinVaListType();
7634    assert(!Type.isNull() && "builtin va list type not initialized!");
7635    break;
7636  case 'A':
7637    // This is a "reference" to a va_list; however, what exactly
7638    // this means depends on how va_list is defined. There are two
7639    // different kinds of va_list: ones passed by value, and ones
7640    // passed by reference.  An example of a by-value va_list is
7641    // x86, where va_list is a char*. An example of by-ref va_list
7642    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
7643    // we want this argument to be a char*&; for x86-64, we want
7644    // it to be a __va_list_tag*.
7645    Type = Context.getBuiltinVaListType();
7646    assert(!Type.isNull() && "builtin va list type not initialized!");
7647    if (Type->isArrayType())
7648      Type = Context.getArrayDecayedType(Type);
7649    else
7650      Type = Context.getLValueReferenceType(Type);
7651    break;
7652  case 'V': {
7653    char *End;
7654    unsigned NumElements = strtoul(Str, &End, 10);
7655    assert(End != Str && "Missing vector size");
7656    Str = End;
7657
7658    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
7659                                             RequiresICE, false);
7660    assert(!RequiresICE && "Can't require vector ICE");
7661
7662    // TODO: No way to make AltiVec vectors in builtins yet.
7663    Type = Context.getVectorType(ElementType, NumElements,
7664                                 VectorType::GenericVector);
7665    break;
7666  }
7667  case 'E': {
7668    char *End;
7669
7670    unsigned NumElements = strtoul(Str, &End, 10);
7671    assert(End != Str && "Missing vector size");
7672
7673    Str = End;
7674
7675    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
7676                                             false);
7677    Type = Context.getExtVectorType(ElementType, NumElements);
7678    break;
7679  }
7680  case 'X': {
7681    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
7682                                             false);
7683    assert(!RequiresICE && "Can't require complex ICE");
7684    Type = Context.getComplexType(ElementType);
7685    break;
7686  }
7687  case 'Y' : {
7688    Type = Context.getPointerDiffType();
7689    break;
7690  }
7691  case 'P':
7692    Type = Context.getFILEType();
7693    if (Type.isNull()) {
7694      Error = ASTContext::GE_Missing_stdio;
7695      return QualType();
7696    }
7697    break;
7698  case 'J':
7699    if (Signed)
7700      Type = Context.getsigjmp_bufType();
7701    else
7702      Type = Context.getjmp_bufType();
7703
7704    if (Type.isNull()) {
7705      Error = ASTContext::GE_Missing_setjmp;
7706      return QualType();
7707    }
7708    break;
7709  case 'K':
7710    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'K'!");
7711    Type = Context.getucontext_tType();
7712
7713    if (Type.isNull()) {
7714      Error = ASTContext::GE_Missing_ucontext;
7715      return QualType();
7716    }
7717    break;
7718  case 'p':
7719    Type = Context.getProcessIDType();
7720    break;
7721  }
7722
7723  // If there are modifiers and if we're allowed to parse them, go for it.
7724  Done = !AllowTypeModifiers;
7725  while (!Done) {
7726    switch (char c = *Str++) {
7727    default: Done = true; --Str; break;
7728    case '*':
7729    case '&': {
7730      // Both pointers and references can have their pointee types
7731      // qualified with an address space.
7732      char *End;
7733      unsigned AddrSpace = strtoul(Str, &End, 10);
7734      if (End != Str && AddrSpace != 0) {
7735        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
7736        Str = End;
7737      }
7738      if (c == '*')
7739        Type = Context.getPointerType(Type);
7740      else
7741        Type = Context.getLValueReferenceType(Type);
7742      break;
7743    }
7744    // FIXME: There's no way to have a built-in with an rvalue ref arg.
7745    case 'C':
7746      Type = Type.withConst();
7747      break;
7748    case 'D':
7749      Type = Context.getVolatileType(Type);
7750      break;
7751    case 'R':
7752      Type = Type.withRestrict();
7753      break;
7754    }
7755  }
7756
7757  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
7758         "Integer constant 'I' type must be an integer");
7759
7760  return Type;
7761}
7762
7763/// GetBuiltinType - Return the type for the specified builtin.
7764QualType ASTContext::GetBuiltinType(unsigned Id,
7765                                    GetBuiltinTypeError &Error,
7766                                    unsigned *IntegerConstantArgs) const {
7767  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
7768
7769  SmallVector<QualType, 8> ArgTypes;
7770
7771  bool RequiresICE = false;
7772  Error = GE_None;
7773  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
7774                                       RequiresICE, true);
7775  if (Error != GE_None)
7776    return QualType();
7777
7778  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
7779
7780  while (TypeStr[0] && TypeStr[0] != '.') {
7781    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
7782    if (Error != GE_None)
7783      return QualType();
7784
7785    // If this argument is required to be an IntegerConstantExpression and the
7786    // caller cares, fill in the bitmask we return.
7787    if (RequiresICE && IntegerConstantArgs)
7788      *IntegerConstantArgs |= 1 << ArgTypes.size();
7789
7790    // Do array -> pointer decay.  The builtin should use the decayed type.
7791    if (Ty->isArrayType())
7792      Ty = getArrayDecayedType(Ty);
7793
7794    ArgTypes.push_back(Ty);
7795  }
7796
7797  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
7798         "'.' should only occur at end of builtin type list!");
7799
7800  FunctionType::ExtInfo EI(CC_C);
7801  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
7802
7803  bool Variadic = (TypeStr[0] == '.');
7804
7805  // We really shouldn't be making a no-proto type here, especially in C++.
7806  if (ArgTypes.empty() && Variadic)
7807    return getFunctionNoProtoType(ResType, EI);
7808
7809  FunctionProtoType::ExtProtoInfo EPI;
7810  EPI.ExtInfo = EI;
7811  EPI.Variadic = Variadic;
7812
7813  return getFunctionType(ResType, ArgTypes, EPI);
7814}
7815
7816GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
7817  if (!FD->isExternallyVisible())
7818    return GVA_Internal;
7819
7820  GVALinkage External = GVA_StrongExternal;
7821  switch (FD->getTemplateSpecializationKind()) {
7822  case TSK_Undeclared:
7823  case TSK_ExplicitSpecialization:
7824    External = GVA_StrongExternal;
7825    break;
7826
7827  case TSK_ExplicitInstantiationDefinition:
7828    return GVA_ExplicitTemplateInstantiation;
7829
7830  case TSK_ExplicitInstantiationDeclaration:
7831  case TSK_ImplicitInstantiation:
7832    External = GVA_TemplateInstantiation;
7833    break;
7834  }
7835
7836  if (!FD->isInlined())
7837    return External;
7838
7839  if ((!getLangOpts().CPlusPlus && !getLangOpts().MicrosoftMode) ||
7840      FD->hasAttr<GNUInlineAttr>()) {
7841    // GNU or C99 inline semantics. Determine whether this symbol should be
7842    // externally visible.
7843    if (FD->isInlineDefinitionExternallyVisible())
7844      return External;
7845
7846    // C99 inline semantics, where the symbol is not externally visible.
7847    return GVA_C99Inline;
7848  }
7849
7850  // C++0x [temp.explicit]p9:
7851  //   [ Note: The intent is that an inline function that is the subject of
7852  //   an explicit instantiation declaration will still be implicitly
7853  //   instantiated when used so that the body can be considered for
7854  //   inlining, but that no out-of-line copy of the inline function would be
7855  //   generated in the translation unit. -- end note ]
7856  if (FD->getTemplateSpecializationKind()
7857                                       == TSK_ExplicitInstantiationDeclaration)
7858    return GVA_C99Inline;
7859
7860  return GVA_CXXInline;
7861}
7862
7863GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
7864  if (!VD->isExternallyVisible())
7865    return GVA_Internal;
7866
7867  switch (VD->getTemplateSpecializationKind()) {
7868  case TSK_Undeclared:
7869  case TSK_ExplicitSpecialization:
7870    return GVA_StrongExternal;
7871
7872  case TSK_ExplicitInstantiationDeclaration:
7873    llvm_unreachable("Variable should not be instantiated");
7874  // Fall through to treat this like any other instantiation.
7875
7876  case TSK_ExplicitInstantiationDefinition:
7877    return GVA_ExplicitTemplateInstantiation;
7878
7879  case TSK_ImplicitInstantiation:
7880    return GVA_TemplateInstantiation;
7881  }
7882
7883  llvm_unreachable("Invalid Linkage!");
7884}
7885
7886bool ASTContext::DeclMustBeEmitted(const Decl *D) {
7887  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
7888    if (!VD->isFileVarDecl())
7889      return false;
7890  } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
7891    // We never need to emit an uninstantiated function template.
7892    if (FD->getTemplatedKind() == FunctionDecl::TK_FunctionTemplate)
7893      return false;
7894  } else
7895    return false;
7896
7897  // If this is a member of a class template, we do not need to emit it.
7898  if (D->getDeclContext()->isDependentContext())
7899    return false;
7900
7901  // Weak references don't produce any output by themselves.
7902  if (D->hasAttr<WeakRefAttr>())
7903    return false;
7904
7905  // Aliases and used decls are required.
7906  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
7907    return true;
7908
7909  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
7910    // Forward declarations aren't required.
7911    if (!FD->doesThisDeclarationHaveABody())
7912      return FD->doesDeclarationForceExternallyVisibleDefinition();
7913
7914    // Constructors and destructors are required.
7915    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
7916      return true;
7917
7918    // The key function for a class is required.  This rule only comes
7919    // into play when inline functions can be key functions, though.
7920    if (getTargetInfo().getCXXABI().canKeyFunctionBeInline()) {
7921      if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
7922        const CXXRecordDecl *RD = MD->getParent();
7923        if (MD->isOutOfLine() && RD->isDynamicClass()) {
7924          const CXXMethodDecl *KeyFunc = getCurrentKeyFunction(RD);
7925          if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
7926            return true;
7927        }
7928      }
7929    }
7930
7931    GVALinkage Linkage = GetGVALinkageForFunction(FD);
7932
7933    // static, static inline, always_inline, and extern inline functions can
7934    // always be deferred.  Normal inline functions can be deferred in C99/C++.
7935    // Implicit template instantiations can also be deferred in C++.
7936    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
7937        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
7938      return false;
7939    return true;
7940  }
7941
7942  const VarDecl *VD = cast<VarDecl>(D);
7943  assert(VD->isFileVarDecl() && "Expected file scoped var");
7944
7945  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
7946    return false;
7947
7948  // Variables that can be needed in other TUs are required.
7949  GVALinkage L = GetGVALinkageForVariable(VD);
7950  if (L != GVA_Internal && L != GVA_TemplateInstantiation)
7951    return true;
7952
7953  // Variables that have destruction with side-effects are required.
7954  if (VD->getType().isDestructedType())
7955    return true;
7956
7957  // Variables that have initialization with side-effects are required.
7958  if (VD->getInit() && VD->getInit()->HasSideEffects(*this))
7959    return true;
7960
7961  return false;
7962}
7963
7964CallingConv ASTContext::getDefaultCallingConvention(bool IsVariadic,
7965                                                    bool IsCXXMethod) const {
7966  // Pass through to the C++ ABI object
7967  if (IsCXXMethod)
7968    return ABI->getDefaultMethodCallConv(IsVariadic);
7969
7970  return (LangOpts.MRTD && !IsVariadic) ? CC_X86StdCall : CC_C;
7971}
7972
7973bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
7974  // Pass through to the C++ ABI object
7975  return ABI->isNearlyEmpty(RD);
7976}
7977
7978MangleContext *ASTContext::createMangleContext() {
7979  switch (Target->getCXXABI().getKind()) {
7980  case TargetCXXABI::GenericAArch64:
7981  case TargetCXXABI::GenericItanium:
7982  case TargetCXXABI::GenericARM:
7983  case TargetCXXABI::iOS:
7984    return ItaniumMangleContext::create(*this, getDiagnostics());
7985  case TargetCXXABI::Microsoft:
7986    return MicrosoftMangleContext::create(*this, getDiagnostics());
7987  }
7988  llvm_unreachable("Unsupported ABI");
7989}
7990
7991CXXABI::~CXXABI() {}
7992
7993size_t ASTContext::getSideTableAllocatedMemory() const {
7994  return ASTRecordLayouts.getMemorySize() +
7995         llvm::capacity_in_bytes(ObjCLayouts) +
7996         llvm::capacity_in_bytes(KeyFunctions) +
7997         llvm::capacity_in_bytes(ObjCImpls) +
7998         llvm::capacity_in_bytes(BlockVarCopyInits) +
7999         llvm::capacity_in_bytes(DeclAttrs) +
8000         llvm::capacity_in_bytes(TemplateOrInstantiation) +
8001         llvm::capacity_in_bytes(InstantiatedFromUsingDecl) +
8002         llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl) +
8003         llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl) +
8004         llvm::capacity_in_bytes(OverriddenMethods) +
8005         llvm::capacity_in_bytes(Types) +
8006         llvm::capacity_in_bytes(VariableArrayTypes) +
8007         llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
8008}
8009
8010/// getIntTypeForBitwidth -
8011/// sets integer QualTy according to specified details:
8012/// bitwidth, signed/unsigned.
8013/// Returns empty type if there is no appropriate target types.
8014QualType ASTContext::getIntTypeForBitwidth(unsigned DestWidth,
8015                                           unsigned Signed) const {
8016  TargetInfo::IntType Ty = getTargetInfo().getIntTypeByWidth(DestWidth, Signed);
8017  CanQualType QualTy = getFromTargetType(Ty);
8018  if (!QualTy && DestWidth == 128)
8019    return Signed ? Int128Ty : UnsignedInt128Ty;
8020  return QualTy;
8021}
8022
8023/// getRealTypeForBitwidth -
8024/// sets floating point QualTy according to specified bitwidth.
8025/// Returns empty type if there is no appropriate target types.
8026QualType ASTContext::getRealTypeForBitwidth(unsigned DestWidth) const {
8027  TargetInfo::RealType Ty = getTargetInfo().getRealTypeByWidth(DestWidth);
8028  switch (Ty) {
8029  case TargetInfo::Float:
8030    return FloatTy;
8031  case TargetInfo::Double:
8032    return DoubleTy;
8033  case TargetInfo::LongDouble:
8034    return LongDoubleTy;
8035  case TargetInfo::NoFloat:
8036    return QualType();
8037  }
8038
8039  llvm_unreachable("Unhandled TargetInfo::RealType value");
8040}
8041
8042void ASTContext::setManglingNumber(const NamedDecl *ND, unsigned Number) {
8043  if (Number > 1)
8044    MangleNumbers[ND] = Number;
8045}
8046
8047unsigned ASTContext::getManglingNumber(const NamedDecl *ND) const {
8048  llvm::DenseMap<const NamedDecl *, unsigned>::const_iterator I =
8049    MangleNumbers.find(ND);
8050  return I != MangleNumbers.end() ? I->second : 1;
8051}
8052
8053MangleNumberingContext &
8054ASTContext::getManglingNumberContext(const DeclContext *DC) {
8055  assert(LangOpts.CPlusPlus);  // We don't need mangling numbers for plain C.
8056  MangleNumberingContext *&MCtx = MangleNumberingContexts[DC];
8057  if (!MCtx)
8058    MCtx = createMangleNumberingContext();
8059  return *MCtx;
8060}
8061
8062MangleNumberingContext *ASTContext::createMangleNumberingContext() const {
8063  return ABI->createMangleNumberingContext();
8064}
8065
8066void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
8067  ParamIndices[D] = index;
8068}
8069
8070unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
8071  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
8072  assert(I != ParamIndices.end() &&
8073         "ParmIndices lacks entry set by ParmVarDecl");
8074  return I->second;
8075}
8076
8077APValue *
8078ASTContext::getMaterializedTemporaryValue(const MaterializeTemporaryExpr *E,
8079                                          bool MayCreate) {
8080  assert(E && E->getStorageDuration() == SD_Static &&
8081         "don't need to cache the computed value for this temporary");
8082  if (MayCreate)
8083    return &MaterializedTemporaryValues[E];
8084
8085  llvm::DenseMap<const MaterializeTemporaryExpr *, APValue>::iterator I =
8086      MaterializedTemporaryValues.find(E);
8087  return I == MaterializedTemporaryValues.end() ? 0 : &I->second;
8088}
8089
8090bool ASTContext::AtomicUsesUnsupportedLibcall(const AtomicExpr *E) const {
8091  const llvm::Triple &T = getTargetInfo().getTriple();
8092  if (!T.isOSDarwin())
8093    return false;
8094
8095  QualType AtomicTy = E->getPtr()->getType()->getPointeeType();
8096  CharUnits sizeChars = getTypeSizeInChars(AtomicTy);
8097  uint64_t Size = sizeChars.getQuantity();
8098  CharUnits alignChars = getTypeAlignInChars(AtomicTy);
8099  unsigned Align = alignChars.getQuantity();
8100  unsigned MaxInlineWidthInBits = getTargetInfo().getMaxAtomicInlineWidth();
8101  return (Size != Align || toBits(sizeChars) > MaxInlineWidthInBits);
8102}
8103
8104namespace {
8105
8106  /// \brief A \c RecursiveASTVisitor that builds a map from nodes to their
8107  /// parents as defined by the \c RecursiveASTVisitor.
8108  ///
8109  /// Note that the relationship described here is purely in terms of AST
8110  /// traversal - there are other relationships (for example declaration context)
8111  /// in the AST that are better modeled by special matchers.
8112  ///
8113  /// FIXME: Currently only builds up the map using \c Stmt and \c Decl nodes.
8114  class ParentMapASTVisitor : public RecursiveASTVisitor<ParentMapASTVisitor> {
8115
8116  public:
8117    /// \brief Builds and returns the translation unit's parent map.
8118    ///
8119    ///  The caller takes ownership of the returned \c ParentMap.
8120    static ASTContext::ParentMap *buildMap(TranslationUnitDecl &TU) {
8121      ParentMapASTVisitor Visitor(new ASTContext::ParentMap);
8122      Visitor.TraverseDecl(&TU);
8123      return Visitor.Parents;
8124    }
8125
8126  private:
8127    typedef RecursiveASTVisitor<ParentMapASTVisitor> VisitorBase;
8128
8129    ParentMapASTVisitor(ASTContext::ParentMap *Parents) : Parents(Parents) {
8130    }
8131
8132    bool shouldVisitTemplateInstantiations() const {
8133      return true;
8134    }
8135    bool shouldVisitImplicitCode() const {
8136      return true;
8137    }
8138    // Disables data recursion. We intercept Traverse* methods in the RAV, which
8139    // are not triggered during data recursion.
8140    bool shouldUseDataRecursionFor(clang::Stmt *S) const {
8141      return false;
8142    }
8143
8144    template <typename T>
8145    bool TraverseNode(T *Node, bool(VisitorBase:: *traverse) (T *)) {
8146      if (Node == NULL)
8147        return true;
8148      if (ParentStack.size() > 0)
8149        // FIXME: Currently we add the same parent multiple times, for example
8150        // when we visit all subexpressions of template instantiations; this is
8151        // suboptimal, bug benign: the only way to visit those is with
8152        // hasAncestor / hasParent, and those do not create new matches.
8153        // The plan is to enable DynTypedNode to be storable in a map or hash
8154        // map. The main problem there is to implement hash functions /
8155        // comparison operators for all types that DynTypedNode supports that
8156        // do not have pointer identity.
8157        (*Parents)[Node].push_back(ParentStack.back());
8158      ParentStack.push_back(ast_type_traits::DynTypedNode::create(*Node));
8159      bool Result = (this ->* traverse) (Node);
8160      ParentStack.pop_back();
8161      return Result;
8162    }
8163
8164    bool TraverseDecl(Decl *DeclNode) {
8165      return TraverseNode(DeclNode, &VisitorBase::TraverseDecl);
8166    }
8167
8168    bool TraverseStmt(Stmt *StmtNode) {
8169      return TraverseNode(StmtNode, &VisitorBase::TraverseStmt);
8170    }
8171
8172    ASTContext::ParentMap *Parents;
8173    llvm::SmallVector<ast_type_traits::DynTypedNode, 16> ParentStack;
8174
8175    friend class RecursiveASTVisitor<ParentMapASTVisitor>;
8176  };
8177
8178} // end namespace
8179
8180ASTContext::ParentVector
8181ASTContext::getParents(const ast_type_traits::DynTypedNode &Node) {
8182  assert(Node.getMemoizationData() &&
8183         "Invariant broken: only nodes that support memoization may be "
8184         "used in the parent map.");
8185  if (!AllParents) {
8186    // We always need to run over the whole translation unit, as
8187    // hasAncestor can escape any subtree.
8188    AllParents.reset(
8189        ParentMapASTVisitor::buildMap(*getTranslationUnitDecl()));
8190  }
8191  ParentMap::const_iterator I = AllParents->find(Node.getMemoizationData());
8192  if (I == AllParents->end()) {
8193    return ParentVector();
8194  }
8195  return I->second;
8196}
8197
8198bool
8199ASTContext::ObjCMethodsAreEqual(const ObjCMethodDecl *MethodDecl,
8200                                const ObjCMethodDecl *MethodImpl) {
8201  // No point trying to match an unavailable/deprecated mothod.
8202  if (MethodDecl->hasAttr<UnavailableAttr>()
8203      || MethodDecl->hasAttr<DeprecatedAttr>())
8204    return false;
8205  if (MethodDecl->getObjCDeclQualifier() !=
8206      MethodImpl->getObjCDeclQualifier())
8207    return false;
8208  if (!hasSameType(MethodDecl->getResultType(),
8209                   MethodImpl->getResultType()))
8210    return false;
8211
8212  if (MethodDecl->param_size() != MethodImpl->param_size())
8213    return false;
8214
8215  for (ObjCMethodDecl::param_const_iterator IM = MethodImpl->param_begin(),
8216       IF = MethodDecl->param_begin(), EM = MethodImpl->param_end(),
8217       EF = MethodDecl->param_end();
8218       IM != EM && IF != EF; ++IM, ++IF) {
8219    const ParmVarDecl *DeclVar = (*IF);
8220    const ParmVarDecl *ImplVar = (*IM);
8221    if (ImplVar->getObjCDeclQualifier() != DeclVar->getObjCDeclQualifier())
8222      return false;
8223    if (!hasSameType(DeclVar->getType(), ImplVar->getType()))
8224      return false;
8225  }
8226  return (MethodDecl->isVariadic() == MethodImpl->isVariadic());
8227
8228}
8229