ASTContext.cpp revision ecb5819a9e64fb654d46a3b270a286cc570c58ff 
1//===--- ASTContext.cpp - Context to hold long-lived AST nodes ------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements the ASTContext interface.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/AST/ASTContext.h"
15#include "CXXABI.h"
16#include "clang/AST/ASTMutationListener.h"
17#include "clang/AST/Attr.h"
18#include "clang/AST/CharUnits.h"
19#include "clang/AST/Comment.h"
20#include "clang/AST/CommentCommandTraits.h"
21#include "clang/AST/DeclCXX.h"
22#include "clang/AST/DeclObjC.h"
23#include "clang/AST/DeclTemplate.h"
24#include "clang/AST/Expr.h"
25#include "clang/AST/ExprCXX.h"
26#include "clang/AST/ExternalASTSource.h"
27#include "clang/AST/Mangle.h"
28#include "clang/AST/RecordLayout.h"
29#include "clang/AST/RecursiveASTVisitor.h"
30#include "clang/AST/TypeLoc.h"
31#include "clang/Basic/Builtins.h"
32#include "clang/Basic/SourceManager.h"
33#include "clang/Basic/TargetInfo.h"
34#include "llvm/ADT/SmallString.h"
35#include "llvm/ADT/StringExtras.h"
36#include "llvm/Support/Capacity.h"
37#include "llvm/Support/MathExtras.h"
38#include "llvm/Support/raw_ostream.h"
39#include <map>
40
41using namespace clang;
42
43unsigned ASTContext::NumImplicitDefaultConstructors;
44unsigned ASTContext::NumImplicitDefaultConstructorsDeclared;
45unsigned ASTContext::NumImplicitCopyConstructors;
46unsigned ASTContext::NumImplicitCopyConstructorsDeclared;
47unsigned ASTContext::NumImplicitMoveConstructors;
48unsigned ASTContext::NumImplicitMoveConstructorsDeclared;
49unsigned ASTContext::NumImplicitCopyAssignmentOperators;
50unsigned ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
51unsigned ASTContext::NumImplicitMoveAssignmentOperators;
52unsigned ASTContext::NumImplicitMoveAssignmentOperatorsDeclared;
53unsigned ASTContext::NumImplicitDestructors;
54unsigned ASTContext::NumImplicitDestructorsDeclared;
55
56enum FloatingRank {
57  HalfRank, FloatRank, DoubleRank, LongDoubleRank
58};
59
60RawComment *ASTContext::getRawCommentForDeclNoCache(const Decl *D) const {
61  if (!CommentsLoaded && ExternalSource) {
62    ExternalSource->ReadComments();
63    CommentsLoaded = true;
64  }
65
66  assert(D);
67
68  // User can not attach documentation to implicit declarations.
69  if (D->isImplicit())
70    return NULL;
71
72  // User can not attach documentation to implicit instantiations.
73  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
74    if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
75      return NULL;
76  }
77
78  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
79    if (VD->isStaticDataMember() &&
80        VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
81      return NULL;
82  }
83
84  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(D)) {
85    if (CRD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
86      return NULL;
87  }
88
89  if (const ClassTemplateSpecializationDecl *CTSD =
90          dyn_cast<ClassTemplateSpecializationDecl>(D)) {
91    TemplateSpecializationKind TSK = CTSD->getSpecializationKind();
92    if (TSK == TSK_ImplicitInstantiation ||
93        TSK == TSK_Undeclared)
94      return NULL;
95  }
96
97  if (const EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
98    if (ED->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
99      return NULL;
100  }
101  if (const TagDecl *TD = dyn_cast<TagDecl>(D)) {
102    // When tag declaration (but not definition!) is part of the
103    // decl-specifier-seq of some other declaration, it doesn't get comment
104    if (TD->isEmbeddedInDeclarator() && !TD->isCompleteDefinition())
105      return NULL;
106  }
107  // TODO: handle comments for function parameters properly.
108  if (isa<ParmVarDecl>(D))
109    return NULL;
110
111  // TODO: we could look up template parameter documentation in the template
112  // documentation.
113  if (isa<TemplateTypeParmDecl>(D) ||
114      isa<NonTypeTemplateParmDecl>(D) ||
115      isa<TemplateTemplateParmDecl>(D))
116    return NULL;
117
118  ArrayRef<RawComment *> RawComments = Comments.getComments();
119
120  // If there are no comments anywhere, we won't find anything.
121  if (RawComments.empty())
122    return NULL;
123
124  // Find declaration location.
125  // For Objective-C declarations we generally don't expect to have multiple
126  // declarators, thus use declaration starting location as the "declaration
127  // location".
128  // For all other declarations multiple declarators are used quite frequently,
129  // so we use the location of the identifier as the "declaration location".
130  SourceLocation DeclLoc;
131  if (isa<ObjCMethodDecl>(D) || isa<ObjCContainerDecl>(D) ||
132      isa<ObjCPropertyDecl>(D) ||
133      isa<RedeclarableTemplateDecl>(D) ||
134      isa<ClassTemplateSpecializationDecl>(D))
135    DeclLoc = D->getLocStart();
136  else {
137    DeclLoc = D->getLocation();
138    // If location of the typedef name is in a macro, it is because being
139    // declared via a macro. Try using declaration's starting location
140    // as the "declaration location".
141    if (DeclLoc.isMacroID() && isa<TypedefDecl>(D))
142      DeclLoc = D->getLocStart();
143  }
144
145  // If the declaration doesn't map directly to a location in a file, we
146  // can't find the comment.
147  if (DeclLoc.isInvalid() || !DeclLoc.isFileID())
148    return NULL;
149
150  // Find the comment that occurs just after this declaration.
151  ArrayRef<RawComment *>::iterator Comment;
152  {
153    // When searching for comments during parsing, the comment we are looking
154    // for is usually among the last two comments we parsed -- check them
155    // first.
156    RawComment CommentAtDeclLoc(
157        SourceMgr, SourceRange(DeclLoc), false,
158        LangOpts.CommentOpts.ParseAllComments);
159    BeforeThanCompare<RawComment> Compare(SourceMgr);
160    ArrayRef<RawComment *>::iterator MaybeBeforeDecl = RawComments.end() - 1;
161    bool Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
162    if (!Found && RawComments.size() >= 2) {
163      MaybeBeforeDecl--;
164      Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
165    }
166
167    if (Found) {
168      Comment = MaybeBeforeDecl + 1;
169      assert(Comment == std::lower_bound(RawComments.begin(), RawComments.end(),
170                                         &CommentAtDeclLoc, Compare));
171    } else {
172      // Slow path.
173      Comment = std::lower_bound(RawComments.begin(), RawComments.end(),
174                                 &CommentAtDeclLoc, Compare);
175    }
176  }
177
178  // Decompose the location for the declaration and find the beginning of the
179  // file buffer.
180  std::pair<FileID, unsigned> DeclLocDecomp = SourceMgr.getDecomposedLoc(DeclLoc);
181
182  // First check whether we have a trailing comment.
183  if (Comment != RawComments.end() &&
184      (*Comment)->isDocumentation() && (*Comment)->isTrailingComment() &&
185      (isa<FieldDecl>(D) || isa<EnumConstantDecl>(D) || isa<VarDecl>(D) ||
186       isa<ObjCMethodDecl>(D) || isa<ObjCPropertyDecl>(D))) {
187    std::pair<FileID, unsigned> CommentBeginDecomp
188      = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getBegin());
189    // Check that Doxygen trailing comment comes after the declaration, starts
190    // on the same line and in the same file as the declaration.
191    if (DeclLocDecomp.first == CommentBeginDecomp.first &&
192        SourceMgr.getLineNumber(DeclLocDecomp.first, DeclLocDecomp.second)
193          == SourceMgr.getLineNumber(CommentBeginDecomp.first,
194                                     CommentBeginDecomp.second)) {
195      return *Comment;
196    }
197  }
198
199  // The comment just after the declaration was not a trailing comment.
200  // Let's look at the previous comment.
201  if (Comment == RawComments.begin())
202    return NULL;
203  --Comment;
204
205  // Check that we actually have a non-member Doxygen comment.
206  if (!(*Comment)->isDocumentation() || (*Comment)->isTrailingComment())
207    return NULL;
208
209  // Decompose the end of the comment.
210  std::pair<FileID, unsigned> CommentEndDecomp
211    = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getEnd());
212
213  // If the comment and the declaration aren't in the same file, then they
214  // aren't related.
215  if (DeclLocDecomp.first != CommentEndDecomp.first)
216    return NULL;
217
218  // Get the corresponding buffer.
219  bool Invalid = false;
220  const char *Buffer = SourceMgr.getBufferData(DeclLocDecomp.first,
221                                               &Invalid).data();
222  if (Invalid)
223    return NULL;
224
225  // Extract text between the comment and declaration.
226  StringRef Text(Buffer + CommentEndDecomp.second,
227                 DeclLocDecomp.second - CommentEndDecomp.second);
228
229  // There should be no other declarations or preprocessor directives between
230  // comment and declaration.
231  if (Text.find_first_of(";{}#@") != StringRef::npos)
232    return NULL;
233
234  return *Comment;
235}
236
237namespace {
238/// If we have a 'templated' declaration for a template, adjust 'D' to
239/// refer to the actual template.
240/// If we have an implicit instantiation, adjust 'D' to refer to template.
241const Decl *adjustDeclToTemplate(const Decl *D) {
242  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
243    // Is this function declaration part of a function template?
244    if (const FunctionTemplateDecl *FTD = FD->getDescribedFunctionTemplate())
245      return FTD;
246
247    // Nothing to do if function is not an implicit instantiation.
248    if (FD->getTemplateSpecializationKind() != TSK_ImplicitInstantiation)
249      return D;
250
251    // Function is an implicit instantiation of a function template?
252    if (const FunctionTemplateDecl *FTD = FD->getPrimaryTemplate())
253      return FTD;
254
255    // Function is instantiated from a member definition of a class template?
256    if (const FunctionDecl *MemberDecl =
257            FD->getInstantiatedFromMemberFunction())
258      return MemberDecl;
259
260    return D;
261  }
262  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
263    // Static data member is instantiated from a member definition of a class
264    // template?
265    if (VD->isStaticDataMember())
266      if (const VarDecl *MemberDecl = VD->getInstantiatedFromStaticDataMember())
267        return MemberDecl;
268
269    return D;
270  }
271  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(D)) {
272    // Is this class declaration part of a class template?
273    if (const ClassTemplateDecl *CTD = CRD->getDescribedClassTemplate())
274      return CTD;
275
276    // Class is an implicit instantiation of a class template or partial
277    // specialization?
278    if (const ClassTemplateSpecializationDecl *CTSD =
279            dyn_cast<ClassTemplateSpecializationDecl>(CRD)) {
280      if (CTSD->getSpecializationKind() != TSK_ImplicitInstantiation)
281        return D;
282      llvm::PointerUnion<ClassTemplateDecl *,
283                         ClassTemplatePartialSpecializationDecl *>
284          PU = CTSD->getSpecializedTemplateOrPartial();
285      return PU.is<ClassTemplateDecl*>() ?
286          static_cast<const Decl*>(PU.get<ClassTemplateDecl *>()) :
287          static_cast<const Decl*>(
288              PU.get<ClassTemplatePartialSpecializationDecl *>());
289    }
290
291    // Class is instantiated from a member definition of a class template?
292    if (const MemberSpecializationInfo *Info =
293                   CRD->getMemberSpecializationInfo())
294      return Info->getInstantiatedFrom();
295
296    return D;
297  }
298  if (const EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
299    // Enum is instantiated from a member definition of a class template?
300    if (const EnumDecl *MemberDecl = ED->getInstantiatedFromMemberEnum())
301      return MemberDecl;
302
303    return D;
304  }
305  // FIXME: Adjust alias templates?
306  return D;
307}
308} // unnamed namespace
309
310const RawComment *ASTContext::getRawCommentForAnyRedecl(
311                                                const Decl *D,
312                                                const Decl **OriginalDecl) const {
313  D = adjustDeclToTemplate(D);
314
315  // Check whether we have cached a comment for this declaration already.
316  {
317    llvm::DenseMap<const Decl *, RawCommentAndCacheFlags>::iterator Pos =
318        RedeclComments.find(D);
319    if (Pos != RedeclComments.end()) {
320      const RawCommentAndCacheFlags &Raw = Pos->second;
321      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
322        if (OriginalDecl)
323          *OriginalDecl = Raw.getOriginalDecl();
324        return Raw.getRaw();
325      }
326    }
327  }
328
329  // Search for comments attached to declarations in the redeclaration chain.
330  const RawComment *RC = NULL;
331  const Decl *OriginalDeclForRC = NULL;
332  for (Decl::redecl_iterator I = D->redecls_begin(),
333                             E = D->redecls_end();
334       I != E; ++I) {
335    llvm::DenseMap<const Decl *, RawCommentAndCacheFlags>::iterator Pos =
336        RedeclComments.find(*I);
337    if (Pos != RedeclComments.end()) {
338      const RawCommentAndCacheFlags &Raw = Pos->second;
339      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
340        RC = Raw.getRaw();
341        OriginalDeclForRC = Raw.getOriginalDecl();
342        break;
343      }
344    } else {
345      RC = getRawCommentForDeclNoCache(*I);
346      OriginalDeclForRC = *I;
347      RawCommentAndCacheFlags Raw;
348      if (RC) {
349        Raw.setRaw(RC);
350        Raw.setKind(RawCommentAndCacheFlags::FromDecl);
351      } else
352        Raw.setKind(RawCommentAndCacheFlags::NoCommentInDecl);
353      Raw.setOriginalDecl(*I);
354      RedeclComments[*I] = Raw;
355      if (RC)
356        break;
357    }
358  }
359
360  // If we found a comment, it should be a documentation comment.
361  assert(!RC || RC->isDocumentation());
362
363  if (OriginalDecl)
364    *OriginalDecl = OriginalDeclForRC;
365
366  // Update cache for every declaration in the redeclaration chain.
367  RawCommentAndCacheFlags Raw;
368  Raw.setRaw(RC);
369  Raw.setKind(RawCommentAndCacheFlags::FromRedecl);
370  Raw.setOriginalDecl(OriginalDeclForRC);
371
372  for (Decl::redecl_iterator I = D->redecls_begin(),
373                             E = D->redecls_end();
374       I != E; ++I) {
375    RawCommentAndCacheFlags &R = RedeclComments[*I];
376    if (R.getKind() == RawCommentAndCacheFlags::NoCommentInDecl)
377      R = Raw;
378  }
379
380  return RC;
381}
382
383static void addRedeclaredMethods(const ObjCMethodDecl *ObjCMethod,
384                   SmallVectorImpl<const NamedDecl *> &Redeclared) {
385  const DeclContext *DC = ObjCMethod->getDeclContext();
386  if (const ObjCImplDecl *IMD = dyn_cast<ObjCImplDecl>(DC)) {
387    const ObjCInterfaceDecl *ID = IMD->getClassInterface();
388    if (!ID)
389      return;
390    // Add redeclared method here.
391    for (ObjCInterfaceDecl::known_extensions_iterator
392           Ext = ID->known_extensions_begin(),
393           ExtEnd = ID->known_extensions_end();
394         Ext != ExtEnd; ++Ext) {
395      if (ObjCMethodDecl *RedeclaredMethod =
396            Ext->getMethod(ObjCMethod->getSelector(),
397                                  ObjCMethod->isInstanceMethod()))
398        Redeclared.push_back(RedeclaredMethod);
399    }
400  }
401}
402
403comments::FullComment *ASTContext::cloneFullComment(comments::FullComment *FC,
404                                                    const Decl *D) const {
405  comments::DeclInfo *ThisDeclInfo = new (*this) comments::DeclInfo;
406  ThisDeclInfo->CommentDecl = D;
407  ThisDeclInfo->IsFilled = false;
408  ThisDeclInfo->fill();
409  ThisDeclInfo->CommentDecl = FC->getDecl();
410  comments::FullComment *CFC =
411    new (*this) comments::FullComment(FC->getBlocks(),
412                                      ThisDeclInfo);
413  return CFC;
414
415}
416
417comments::FullComment *ASTContext::getLocalCommentForDeclUncached(const Decl *D) const {
418  const RawComment *RC = getRawCommentForDeclNoCache(D);
419  return RC ? RC->parse(*this, 0, D) : 0;
420}
421
422comments::FullComment *ASTContext::getCommentForDecl(
423                                              const Decl *D,
424                                              const Preprocessor *PP) const {
425  if (D->isInvalidDecl())
426    return NULL;
427  D = adjustDeclToTemplate(D);
428
429  const Decl *Canonical = D->getCanonicalDecl();
430  llvm::DenseMap<const Decl *, comments::FullComment *>::iterator Pos =
431      ParsedComments.find(Canonical);
432
433  if (Pos != ParsedComments.end()) {
434    if (Canonical != D) {
435      comments::FullComment *FC = Pos->second;
436      comments::FullComment *CFC = cloneFullComment(FC, D);
437      return CFC;
438    }
439    return Pos->second;
440  }
441
442  const Decl *OriginalDecl;
443
444  const RawComment *RC = getRawCommentForAnyRedecl(D, &OriginalDecl);
445  if (!RC) {
446    if (isa<ObjCMethodDecl>(D) || isa<FunctionDecl>(D)) {
447      SmallVector<const NamedDecl*, 8> Overridden;
448      const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D);
449      if (OMD && OMD->isPropertyAccessor())
450        if (const ObjCPropertyDecl *PDecl = OMD->findPropertyDecl())
451          if (comments::FullComment *FC = getCommentForDecl(PDecl, PP))
452            return cloneFullComment(FC, D);
453      if (OMD)
454        addRedeclaredMethods(OMD, Overridden);
455      getOverriddenMethods(dyn_cast<NamedDecl>(D), Overridden);
456      for (unsigned i = 0, e = Overridden.size(); i < e; i++)
457        if (comments::FullComment *FC = getCommentForDecl(Overridden[i], PP))
458          return cloneFullComment(FC, D);
459    }
460    else if (const TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(D)) {
461      // Attach any tag type's documentation to its typedef if latter
462      // does not have one of its own.
463      QualType QT = TD->getUnderlyingType();
464      if (const TagType *TT = QT->getAs<TagType>())
465        if (const Decl *TD = TT->getDecl())
466          if (comments::FullComment *FC = getCommentForDecl(TD, PP))
467            return cloneFullComment(FC, D);
468    }
469    else if (const ObjCInterfaceDecl *IC = dyn_cast<ObjCInterfaceDecl>(D)) {
470      while (IC->getSuperClass()) {
471        IC = IC->getSuperClass();
472        if (comments::FullComment *FC = getCommentForDecl(IC, PP))
473          return cloneFullComment(FC, D);
474      }
475    }
476    else if (const ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(D)) {
477      if (const ObjCInterfaceDecl *IC = CD->getClassInterface())
478        if (comments::FullComment *FC = getCommentForDecl(IC, PP))
479          return cloneFullComment(FC, D);
480    }
481    else if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D)) {
482      if (!(RD = RD->getDefinition()))
483        return NULL;
484      // Check non-virtual bases.
485      for (CXXRecordDecl::base_class_const_iterator I =
486           RD->bases_begin(), E = RD->bases_end(); I != E; ++I) {
487        if (I->isVirtual() || (I->getAccessSpecifier() != AS_public))
488          continue;
489        QualType Ty = I->getType();
490        if (Ty.isNull())
491          continue;
492        if (const CXXRecordDecl *NonVirtualBase = Ty->getAsCXXRecordDecl()) {
493          if (!(NonVirtualBase= NonVirtualBase->getDefinition()))
494            continue;
495
496          if (comments::FullComment *FC = getCommentForDecl((NonVirtualBase), PP))
497            return cloneFullComment(FC, D);
498        }
499      }
500      // Check virtual bases.
501      for (CXXRecordDecl::base_class_const_iterator I =
502           RD->vbases_begin(), E = RD->vbases_end(); I != E; ++I) {
503        if (I->getAccessSpecifier() != AS_public)
504          continue;
505        QualType Ty = I->getType();
506        if (Ty.isNull())
507          continue;
508        if (const CXXRecordDecl *VirtualBase = Ty->getAsCXXRecordDecl()) {
509          if (!(VirtualBase= VirtualBase->getDefinition()))
510            continue;
511          if (comments::FullComment *FC = getCommentForDecl((VirtualBase), PP))
512            return cloneFullComment(FC, D);
513        }
514      }
515    }
516    return NULL;
517  }
518
519  // If the RawComment was attached to other redeclaration of this Decl, we
520  // should parse the comment in context of that other Decl.  This is important
521  // because comments can contain references to parameter names which can be
522  // different across redeclarations.
523  if (D != OriginalDecl)
524    return getCommentForDecl(OriginalDecl, PP);
525
526  comments::FullComment *FC = RC->parse(*this, PP, D);
527  ParsedComments[Canonical] = FC;
528  return FC;
529}
530
531void
532ASTContext::CanonicalTemplateTemplateParm::Profile(llvm::FoldingSetNodeID &ID,
533                                               TemplateTemplateParmDecl *Parm) {
534  ID.AddInteger(Parm->getDepth());
535  ID.AddInteger(Parm->getPosition());
536  ID.AddBoolean(Parm->isParameterPack());
537
538  TemplateParameterList *Params = Parm->getTemplateParameters();
539  ID.AddInteger(Params->size());
540  for (TemplateParameterList::const_iterator P = Params->begin(),
541                                          PEnd = Params->end();
542       P != PEnd; ++P) {
543    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P)) {
544      ID.AddInteger(0);
545      ID.AddBoolean(TTP->isParameterPack());
546      continue;
547    }
548
549    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
550      ID.AddInteger(1);
551      ID.AddBoolean(NTTP->isParameterPack());
552      ID.AddPointer(NTTP->getType().getCanonicalType().getAsOpaquePtr());
553      if (NTTP->isExpandedParameterPack()) {
554        ID.AddBoolean(true);
555        ID.AddInteger(NTTP->getNumExpansionTypes());
556        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
557          QualType T = NTTP->getExpansionType(I);
558          ID.AddPointer(T.getCanonicalType().getAsOpaquePtr());
559        }
560      } else
561        ID.AddBoolean(false);
562      continue;
563    }
564
565    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
566    ID.AddInteger(2);
567    Profile(ID, TTP);
568  }
569}
570
571TemplateTemplateParmDecl *
572ASTContext::getCanonicalTemplateTemplateParmDecl(
573                                          TemplateTemplateParmDecl *TTP) const {
574  // Check if we already have a canonical template template parameter.
575  llvm::FoldingSetNodeID ID;
576  CanonicalTemplateTemplateParm::Profile(ID, TTP);
577  void *InsertPos = 0;
578  CanonicalTemplateTemplateParm *Canonical
579    = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
580  if (Canonical)
581    return Canonical->getParam();
582
583  // Build a canonical template parameter list.
584  TemplateParameterList *Params = TTP->getTemplateParameters();
585  SmallVector<NamedDecl *, 4> CanonParams;
586  CanonParams.reserve(Params->size());
587  for (TemplateParameterList::const_iterator P = Params->begin(),
588                                          PEnd = Params->end();
589       P != PEnd; ++P) {
590    if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*P))
591      CanonParams.push_back(
592                  TemplateTypeParmDecl::Create(*this, getTranslationUnitDecl(),
593                                               SourceLocation(),
594                                               SourceLocation(),
595                                               TTP->getDepth(),
596                                               TTP->getIndex(), 0, false,
597                                               TTP->isParameterPack()));
598    else if (NonTypeTemplateParmDecl *NTTP
599             = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
600      QualType T = getCanonicalType(NTTP->getType());
601      TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(T);
602      NonTypeTemplateParmDecl *Param;
603      if (NTTP->isExpandedParameterPack()) {
604        SmallVector<QualType, 2> ExpandedTypes;
605        SmallVector<TypeSourceInfo *, 2> ExpandedTInfos;
606        for (unsigned I = 0, N = NTTP->getNumExpansionTypes(); I != N; ++I) {
607          ExpandedTypes.push_back(getCanonicalType(NTTP->getExpansionType(I)));
608          ExpandedTInfos.push_back(
609                                getTrivialTypeSourceInfo(ExpandedTypes.back()));
610        }
611
612        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
613                                                SourceLocation(),
614                                                SourceLocation(),
615                                                NTTP->getDepth(),
616                                                NTTP->getPosition(), 0,
617                                                T,
618                                                TInfo,
619                                                ExpandedTypes.data(),
620                                                ExpandedTypes.size(),
621                                                ExpandedTInfos.data());
622      } else {
623        Param = NonTypeTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
624                                                SourceLocation(),
625                                                SourceLocation(),
626                                                NTTP->getDepth(),
627                                                NTTP->getPosition(), 0,
628                                                T,
629                                                NTTP->isParameterPack(),
630                                                TInfo);
631      }
632      CanonParams.push_back(Param);
633
634    } else
635      CanonParams.push_back(getCanonicalTemplateTemplateParmDecl(
636                                           cast<TemplateTemplateParmDecl>(*P)));
637  }
638
639  TemplateTemplateParmDecl *CanonTTP
640    = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(),
641                                       SourceLocation(), TTP->getDepth(),
642                                       TTP->getPosition(),
643                                       TTP->isParameterPack(),
644                                       0,
645                         TemplateParameterList::Create(*this, SourceLocation(),
646                                                       SourceLocation(),
647                                                       CanonParams.data(),
648                                                       CanonParams.size(),
649                                                       SourceLocation()));
650
651  // Get the new insert position for the node we care about.
652  Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);
653  assert(Canonical == 0 && "Shouldn't be in the map!");
654  (void)Canonical;
655
656  // Create the canonical template template parameter entry.
657  Canonical = new (*this) CanonicalTemplateTemplateParm(CanonTTP);
658  CanonTemplateTemplateParms.InsertNode(Canonical, InsertPos);
659  return CanonTTP;
660}
661
662CXXABI *ASTContext::createCXXABI(const TargetInfo &T) {
663  if (!LangOpts.CPlusPlus) return 0;
664
665  switch (T.getCXXABI().getKind()) {
666  case TargetCXXABI::GenericARM:
667  case TargetCXXABI::iOS:
668    return CreateARMCXXABI(*this);
669  case TargetCXXABI::GenericAArch64: // Same as Itanium at this level
670  case TargetCXXABI::GenericItanium:
671    return CreateItaniumCXXABI(*this);
672  case TargetCXXABI::Microsoft:
673    return CreateMicrosoftCXXABI(*this);
674  }
675  llvm_unreachable("Invalid CXXABI type!");
676}
677
678static const LangAS::Map *getAddressSpaceMap(const TargetInfo &T,
679                                             const LangOptions &LOpts) {
680  if (LOpts.FakeAddressSpaceMap) {
681    // The fake address space map must have a distinct entry for each
682    // language-specific address space.
683    static const unsigned FakeAddrSpaceMap[] = {
684      1, // opencl_global
685      2, // opencl_local
686      3, // opencl_constant
687      4, // cuda_device
688      5, // cuda_constant
689      6  // cuda_shared
690    };
691    return &FakeAddrSpaceMap;
692  } else {
693    return &T.getAddressSpaceMap();
694  }
695}
696
697ASTContext::ASTContext(LangOptions& LOpts, SourceManager &SM,
698                       const TargetInfo *t,
699                       IdentifierTable &idents, SelectorTable &sels,
700                       Builtin::Context &builtins,
701                       unsigned size_reserve,
702                       bool DelayInitialization)
703  : FunctionProtoTypes(this_()),
704    TemplateSpecializationTypes(this_()),
705    DependentTemplateSpecializationTypes(this_()),
706    SubstTemplateTemplateParmPacks(this_()),
707    GlobalNestedNameSpecifier(0),
708    Int128Decl(0), UInt128Decl(0), Float128StubDecl(0),
709    BuiltinVaListDecl(0),
710    ObjCIdDecl(0), ObjCSelDecl(0), ObjCClassDecl(0), ObjCProtocolClassDecl(0),
711    BOOLDecl(0),
712    CFConstantStringTypeDecl(0), ObjCInstanceTypeDecl(0),
713    FILEDecl(0),
714    jmp_bufDecl(0), sigjmp_bufDecl(0), ucontext_tDecl(0),
715    BlockDescriptorType(0), BlockDescriptorExtendedType(0),
716    cudaConfigureCallDecl(0),
717    NullTypeSourceInfo(QualType()),
718    FirstLocalImport(), LastLocalImport(),
719    SourceMgr(SM), LangOpts(LOpts),
720    AddrSpaceMap(0), Target(t), PrintingPolicy(LOpts),
721    Idents(idents), Selectors(sels),
722    BuiltinInfo(builtins),
723    DeclarationNames(*this),
724    ExternalSource(0), Listener(0),
725    Comments(SM), CommentsLoaded(false),
726    CommentCommandTraits(BumpAlloc, LOpts.CommentOpts),
727    LastSDM(0, 0)
728{
729  if (size_reserve > 0) Types.reserve(size_reserve);
730  TUDecl = TranslationUnitDecl::Create(*this);
731
732  if (!DelayInitialization) {
733    assert(t && "No target supplied for ASTContext initialization");
734    InitBuiltinTypes(*t);
735  }
736}
737
738ASTContext::~ASTContext() {
739  // Release the DenseMaps associated with DeclContext objects.
740  // FIXME: Is this the ideal solution?
741  ReleaseDeclContextMaps();
742
743  // Call all of the deallocation functions on all of their targets.
744  for (DeallocationMap::const_iterator I = Deallocations.begin(),
745           E = Deallocations.end(); I != E; ++I)
746    for (unsigned J = 0, N = I->second.size(); J != N; ++J)
747      (I->first)((I->second)[J]);
748
749  // ASTRecordLayout objects in ASTRecordLayouts must always be destroyed
750  // because they can contain DenseMaps.
751  for (llvm::DenseMap<const ObjCContainerDecl*,
752       const ASTRecordLayout*>::iterator
753       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; )
754    // Increment in loop to prevent using deallocated memory.
755    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
756      R->Destroy(*this);
757
758  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
759       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
760    // Increment in loop to prevent using deallocated memory.
761    if (ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second))
762      R->Destroy(*this);
763  }
764
765  for (llvm::DenseMap<const Decl*, AttrVec*>::iterator A = DeclAttrs.begin(),
766                                                    AEnd = DeclAttrs.end();
767       A != AEnd; ++A)
768    A->second->~AttrVec();
769}
770
771void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
772  Deallocations[Callback].push_back(Data);
773}
774
775void
776ASTContext::setExternalSource(OwningPtr<ExternalASTSource> &Source) {
777  ExternalSource.reset(Source.take());
778}
779
780void ASTContext::PrintStats() const {
781  llvm::errs() << "\n*** AST Context Stats:\n";
782  llvm::errs() << "  " << Types.size() << " types total.\n";
783
784  unsigned counts[] = {
785#define TYPE(Name, Parent) 0,
786#define ABSTRACT_TYPE(Name, Parent)
787#include "clang/AST/TypeNodes.def"
788    0 // Extra
789  };
790
791  for (unsigned i = 0, e = Types.size(); i != e; ++i) {
792    Type *T = Types[i];
793    counts[(unsigned)T->getTypeClass()]++;
794  }
795
796  unsigned Idx = 0;
797  unsigned TotalBytes = 0;
798#define TYPE(Name, Parent)                                              \
799  if (counts[Idx])                                                      \
800    llvm::errs() << "    " << counts[Idx] << " " << #Name               \
801                 << " types\n";                                         \
802  TotalBytes += counts[Idx] * sizeof(Name##Type);                       \
803  ++Idx;
804#define ABSTRACT_TYPE(Name, Parent)
805#include "clang/AST/TypeNodes.def"
806
807  llvm::errs() << "Total bytes = " << TotalBytes << "\n";
808
809  // Implicit special member functions.
810  llvm::errs() << NumImplicitDefaultConstructorsDeclared << "/"
811               << NumImplicitDefaultConstructors
812               << " implicit default constructors created\n";
813  llvm::errs() << NumImplicitCopyConstructorsDeclared << "/"
814               << NumImplicitCopyConstructors
815               << " implicit copy constructors created\n";
816  if (getLangOpts().CPlusPlus)
817    llvm::errs() << NumImplicitMoveConstructorsDeclared << "/"
818                 << NumImplicitMoveConstructors
819                 << " implicit move constructors created\n";
820  llvm::errs() << NumImplicitCopyAssignmentOperatorsDeclared << "/"
821               << NumImplicitCopyAssignmentOperators
822               << " implicit copy assignment operators created\n";
823  if (getLangOpts().CPlusPlus)
824    llvm::errs() << NumImplicitMoveAssignmentOperatorsDeclared << "/"
825                 << NumImplicitMoveAssignmentOperators
826                 << " implicit move assignment operators created\n";
827  llvm::errs() << NumImplicitDestructorsDeclared << "/"
828               << NumImplicitDestructors
829               << " implicit destructors created\n";
830
831  if (ExternalSource.get()) {
832    llvm::errs() << "\n";
833    ExternalSource->PrintStats();
834  }
835
836  BumpAlloc.PrintStats();
837}
838
839TypedefDecl *ASTContext::getInt128Decl() const {
840  if (!Int128Decl) {
841    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(Int128Ty);
842    Int128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
843                                     getTranslationUnitDecl(),
844                                     SourceLocation(),
845                                     SourceLocation(),
846                                     &Idents.get("__int128_t"),
847                                     TInfo);
848  }
849
850  return Int128Decl;
851}
852
853TypedefDecl *ASTContext::getUInt128Decl() const {
854  if (!UInt128Decl) {
855    TypeSourceInfo *TInfo = getTrivialTypeSourceInfo(UnsignedInt128Ty);
856    UInt128Decl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
857                                     getTranslationUnitDecl(),
858                                     SourceLocation(),
859                                     SourceLocation(),
860                                     &Idents.get("__uint128_t"),
861                                     TInfo);
862  }
863
864  return UInt128Decl;
865}
866
867TypeDecl *ASTContext::getFloat128StubType() const {
868  assert(LangOpts.CPlusPlus && "should only be called for c++");
869  if (!Float128StubDecl) {
870    Float128StubDecl = CXXRecordDecl::Create(const_cast<ASTContext &>(*this),
871                                             TTK_Struct,
872                                             getTranslationUnitDecl(),
873                                             SourceLocation(),
874                                             SourceLocation(),
875                                             &Idents.get("__float128"));
876  }
877
878  return Float128StubDecl;
879}
880
881void ASTContext::InitBuiltinType(CanQualType &R, BuiltinType::Kind K) {
882  BuiltinType *Ty = new (*this, TypeAlignment) BuiltinType(K);
883  R = CanQualType::CreateUnsafe(QualType(Ty, 0));
884  Types.push_back(Ty);
885}
886
887void ASTContext::InitBuiltinTypes(const TargetInfo &Target) {
888  assert((!this->Target || this->Target == &Target) &&
889         "Incorrect target reinitialization");
890  assert(VoidTy.isNull() && "Context reinitialized?");
891
892  this->Target = &Target;
893
894  ABI.reset(createCXXABI(Target));
895  AddrSpaceMap = getAddressSpaceMap(Target, LangOpts);
896
897  // C99 6.2.5p19.
898  InitBuiltinType(VoidTy,              BuiltinType::Void);
899
900  // C99 6.2.5p2.
901  InitBuiltinType(BoolTy,              BuiltinType::Bool);
902  // C99 6.2.5p3.
903  if (LangOpts.CharIsSigned)
904    InitBuiltinType(CharTy,            BuiltinType::Char_S);
905  else
906    InitBuiltinType(CharTy,            BuiltinType::Char_U);
907  // C99 6.2.5p4.
908  InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
909  InitBuiltinType(ShortTy,             BuiltinType::Short);
910  InitBuiltinType(IntTy,               BuiltinType::Int);
911  InitBuiltinType(LongTy,              BuiltinType::Long);
912  InitBuiltinType(LongLongTy,          BuiltinType::LongLong);
913
914  // C99 6.2.5p6.
915  InitBuiltinType(UnsignedCharTy,      BuiltinType::UChar);
916  InitBuiltinType(UnsignedShortTy,     BuiltinType::UShort);
917  InitBuiltinType(UnsignedIntTy,       BuiltinType::UInt);
918  InitBuiltinType(UnsignedLongTy,      BuiltinType::ULong);
919  InitBuiltinType(UnsignedLongLongTy,  BuiltinType::ULongLong);
920
921  // C99 6.2.5p10.
922  InitBuiltinType(FloatTy,             BuiltinType::Float);
923  InitBuiltinType(DoubleTy,            BuiltinType::Double);
924  InitBuiltinType(LongDoubleTy,        BuiltinType::LongDouble);
925
926  // GNU extension, 128-bit integers.
927  InitBuiltinType(Int128Ty,            BuiltinType::Int128);
928  InitBuiltinType(UnsignedInt128Ty,    BuiltinType::UInt128);
929
930  // C++ 3.9.1p5
931  if (TargetInfo::isTypeSigned(Target.getWCharType()))
932    InitBuiltinType(WCharTy,           BuiltinType::WChar_S);
933  else  // -fshort-wchar makes wchar_t be unsigned.
934    InitBuiltinType(WCharTy,           BuiltinType::WChar_U);
935  if (LangOpts.CPlusPlus && LangOpts.WChar)
936    WideCharTy = WCharTy;
937  else {
938    // C99 (or C++ using -fno-wchar).
939    WideCharTy = getFromTargetType(Target.getWCharType());
940  }
941
942  WIntTy = getFromTargetType(Target.getWIntType());
943
944  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
945    InitBuiltinType(Char16Ty,           BuiltinType::Char16);
946  else // C99
947    Char16Ty = getFromTargetType(Target.getChar16Type());
948
949  if (LangOpts.CPlusPlus) // C++0x 3.9.1p5, extension for C++
950    InitBuiltinType(Char32Ty,           BuiltinType::Char32);
951  else // C99
952    Char32Ty = getFromTargetType(Target.getChar32Type());
953
954  // Placeholder type for type-dependent expressions whose type is
955  // completely unknown. No code should ever check a type against
956  // DependentTy and users should never see it; however, it is here to
957  // help diagnose failures to properly check for type-dependent
958  // expressions.
959  InitBuiltinType(DependentTy,         BuiltinType::Dependent);
960
961  // Placeholder type for functions.
962  InitBuiltinType(OverloadTy,          BuiltinType::Overload);
963
964  // Placeholder type for bound members.
965  InitBuiltinType(BoundMemberTy,       BuiltinType::BoundMember);
966
967  // Placeholder type for pseudo-objects.
968  InitBuiltinType(PseudoObjectTy,      BuiltinType::PseudoObject);
969
970  // "any" type; useful for debugger-like clients.
971  InitBuiltinType(UnknownAnyTy,        BuiltinType::UnknownAny);
972
973  // Placeholder type for unbridged ARC casts.
974  InitBuiltinType(ARCUnbridgedCastTy,  BuiltinType::ARCUnbridgedCast);
975
976  // Placeholder type for builtin functions.
977  InitBuiltinType(BuiltinFnTy,  BuiltinType::BuiltinFn);
978
979  // C99 6.2.5p11.
980  FloatComplexTy      = getComplexType(FloatTy);
981  DoubleComplexTy     = getComplexType(DoubleTy);
982  LongDoubleComplexTy = getComplexType(LongDoubleTy);
983
984  // Builtin types for 'id', 'Class', and 'SEL'.
985  InitBuiltinType(ObjCBuiltinIdTy, BuiltinType::ObjCId);
986  InitBuiltinType(ObjCBuiltinClassTy, BuiltinType::ObjCClass);
987  InitBuiltinType(ObjCBuiltinSelTy, BuiltinType::ObjCSel);
988
989  if (LangOpts.OpenCL) {
990    InitBuiltinType(OCLImage1dTy, BuiltinType::OCLImage1d);
991    InitBuiltinType(OCLImage1dArrayTy, BuiltinType::OCLImage1dArray);
992    InitBuiltinType(OCLImage1dBufferTy, BuiltinType::OCLImage1dBuffer);
993    InitBuiltinType(OCLImage2dTy, BuiltinType::OCLImage2d);
994    InitBuiltinType(OCLImage2dArrayTy, BuiltinType::OCLImage2dArray);
995    InitBuiltinType(OCLImage3dTy, BuiltinType::OCLImage3d);
996
997    InitBuiltinType(OCLSamplerTy, BuiltinType::OCLSampler);
998    InitBuiltinType(OCLEventTy, BuiltinType::OCLEvent);
999  }
1000
1001  // Builtin type for __objc_yes and __objc_no
1002  ObjCBuiltinBoolTy = (Target.useSignedCharForObjCBool() ?
1003                       SignedCharTy : BoolTy);
1004
1005  ObjCConstantStringType = QualType();
1006
1007  ObjCSuperType = QualType();
1008
1009  // void * type
1010  VoidPtrTy = getPointerType(VoidTy);
1011
1012  // nullptr type (C++0x 2.14.7)
1013  InitBuiltinType(NullPtrTy,           BuiltinType::NullPtr);
1014
1015  // half type (OpenCL 6.1.1.1) / ARM NEON __fp16
1016  InitBuiltinType(HalfTy, BuiltinType::Half);
1017
1018  // Builtin type used to help define __builtin_va_list.
1019  VaListTagTy = QualType();
1020}
1021
1022DiagnosticsEngine &ASTContext::getDiagnostics() const {
1023  return SourceMgr.getDiagnostics();
1024}
1025
1026AttrVec& ASTContext::getDeclAttrs(const Decl *D) {
1027  AttrVec *&Result = DeclAttrs[D];
1028  if (!Result) {
1029    void *Mem = Allocate(sizeof(AttrVec));
1030    Result = new (Mem) AttrVec;
1031  }
1032
1033  return *Result;
1034}
1035
1036/// \brief Erase the attributes corresponding to the given declaration.
1037void ASTContext::eraseDeclAttrs(const Decl *D) {
1038  llvm::DenseMap<const Decl*, AttrVec*>::iterator Pos = DeclAttrs.find(D);
1039  if (Pos != DeclAttrs.end()) {
1040    Pos->second->~AttrVec();
1041    DeclAttrs.erase(Pos);
1042  }
1043}
1044
1045// FIXME: Remove ?
1046MemberSpecializationInfo *
1047ASTContext::getInstantiatedFromStaticDataMember(const VarDecl *Var) {
1048  assert(Var->isStaticDataMember() && "Not a static data member");
1049  return getTemplateOrSpecializationInfo(Var)
1050      .dyn_cast<MemberSpecializationInfo *>();
1051}
1052
1053ASTContext::TemplateOrSpecializationInfo
1054ASTContext::getTemplateOrSpecializationInfo(const VarDecl *Var) {
1055  llvm::DenseMap<const VarDecl *, TemplateOrSpecializationInfo>::iterator Pos =
1056      TemplateOrInstantiation.find(Var);
1057  if (Pos == TemplateOrInstantiation.end())
1058    return TemplateOrSpecializationInfo();
1059
1060  return Pos->second;
1061}
1062
1063void
1064ASTContext::setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
1065                                                TemplateSpecializationKind TSK,
1066                                          SourceLocation PointOfInstantiation) {
1067  assert(Inst->isStaticDataMember() && "Not a static data member");
1068  assert(Tmpl->isStaticDataMember() && "Not a static data member");
1069  setTemplateOrSpecializationInfo(Inst, new (*this) MemberSpecializationInfo(
1070                                            Tmpl, TSK, PointOfInstantiation));
1071}
1072
1073void
1074ASTContext::setTemplateOrSpecializationInfo(VarDecl *Inst,
1075                                            TemplateOrSpecializationInfo TSI) {
1076  assert(!TemplateOrInstantiation[Inst] &&
1077         "Already noted what the variable was instantiated from");
1078  TemplateOrInstantiation[Inst] = TSI;
1079}
1080
1081FunctionDecl *ASTContext::getClassScopeSpecializationPattern(
1082                                                     const FunctionDecl *FD){
1083  assert(FD && "Specialization is 0");
1084  llvm::DenseMap<const FunctionDecl*, FunctionDecl *>::const_iterator Pos
1085    = ClassScopeSpecializationPattern.find(FD);
1086  if (Pos == ClassScopeSpecializationPattern.end())
1087    return 0;
1088
1089  return Pos->second;
1090}
1091
1092void ASTContext::setClassScopeSpecializationPattern(FunctionDecl *FD,
1093                                        FunctionDecl *Pattern) {
1094  assert(FD && "Specialization is 0");
1095  assert(Pattern && "Class scope specialization pattern is 0");
1096  ClassScopeSpecializationPattern[FD] = Pattern;
1097}
1098
1099NamedDecl *
1100ASTContext::getInstantiatedFromUsingDecl(UsingDecl *UUD) {
1101  llvm::DenseMap<UsingDecl *, NamedDecl *>::const_iterator Pos
1102    = InstantiatedFromUsingDecl.find(UUD);
1103  if (Pos == InstantiatedFromUsingDecl.end())
1104    return 0;
1105
1106  return Pos->second;
1107}
1108
1109void
1110ASTContext::setInstantiatedFromUsingDecl(UsingDecl *Inst, NamedDecl *Pattern) {
1111  assert((isa<UsingDecl>(Pattern) ||
1112          isa<UnresolvedUsingValueDecl>(Pattern) ||
1113          isa<UnresolvedUsingTypenameDecl>(Pattern)) &&
1114         "pattern decl is not a using decl");
1115  assert(!InstantiatedFromUsingDecl[Inst] && "pattern already exists");
1116  InstantiatedFromUsingDecl[Inst] = Pattern;
1117}
1118
1119UsingShadowDecl *
1120ASTContext::getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst) {
1121  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>::const_iterator Pos
1122    = InstantiatedFromUsingShadowDecl.find(Inst);
1123  if (Pos == InstantiatedFromUsingShadowDecl.end())
1124    return 0;
1125
1126  return Pos->second;
1127}
1128
1129void
1130ASTContext::setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
1131                                               UsingShadowDecl *Pattern) {
1132  assert(!InstantiatedFromUsingShadowDecl[Inst] && "pattern already exists");
1133  InstantiatedFromUsingShadowDecl[Inst] = Pattern;
1134}
1135
1136FieldDecl *ASTContext::getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field) {
1137  llvm::DenseMap<FieldDecl *, FieldDecl *>::iterator Pos
1138    = InstantiatedFromUnnamedFieldDecl.find(Field);
1139  if (Pos == InstantiatedFromUnnamedFieldDecl.end())
1140    return 0;
1141
1142  return Pos->second;
1143}
1144
1145void ASTContext::setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst,
1146                                                     FieldDecl *Tmpl) {
1147  assert(!Inst->getDeclName() && "Instantiated field decl is not unnamed");
1148  assert(!Tmpl->getDeclName() && "Template field decl is not unnamed");
1149  assert(!InstantiatedFromUnnamedFieldDecl[Inst] &&
1150         "Already noted what unnamed field was instantiated from");
1151
1152  InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
1153}
1154
1155ASTContext::overridden_cxx_method_iterator
1156ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
1157  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1158    = OverriddenMethods.find(Method->getCanonicalDecl());
1159  if (Pos == OverriddenMethods.end())
1160    return 0;
1161
1162  return Pos->second.begin();
1163}
1164
1165ASTContext::overridden_cxx_method_iterator
1166ASTContext::overridden_methods_end(const CXXMethodDecl *Method) const {
1167  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1168    = OverriddenMethods.find(Method->getCanonicalDecl());
1169  if (Pos == OverriddenMethods.end())
1170    return 0;
1171
1172  return Pos->second.end();
1173}
1174
1175unsigned
1176ASTContext::overridden_methods_size(const CXXMethodDecl *Method) const {
1177  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
1178    = OverriddenMethods.find(Method->getCanonicalDecl());
1179  if (Pos == OverriddenMethods.end())
1180    return 0;
1181
1182  return Pos->second.size();
1183}
1184
1185void ASTContext::addOverriddenMethod(const CXXMethodDecl *Method,
1186                                     const CXXMethodDecl *Overridden) {
1187  assert(Method->isCanonicalDecl() && Overridden->isCanonicalDecl());
1188  OverriddenMethods[Method].push_back(Overridden);
1189}
1190
1191void ASTContext::getOverriddenMethods(
1192                      const NamedDecl *D,
1193                      SmallVectorImpl<const NamedDecl *> &Overridden) const {
1194  assert(D);
1195
1196  if (const CXXMethodDecl *CXXMethod = dyn_cast<CXXMethodDecl>(D)) {
1197    Overridden.append(overridden_methods_begin(CXXMethod),
1198                      overridden_methods_end(CXXMethod));
1199    return;
1200  }
1201
1202  const ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(D);
1203  if (!Method)
1204    return;
1205
1206  SmallVector<const ObjCMethodDecl *, 8> OverDecls;
1207  Method->getOverriddenMethods(OverDecls);
1208  Overridden.append(OverDecls.begin(), OverDecls.end());
1209}
1210
1211void ASTContext::addedLocalImportDecl(ImportDecl *Import) {
1212  assert(!Import->NextLocalImport && "Import declaration already in the chain");
1213  assert(!Import->isFromASTFile() && "Non-local import declaration");
1214  if (!FirstLocalImport) {
1215    FirstLocalImport = Import;
1216    LastLocalImport = Import;
1217    return;
1218  }
1219
1220  LastLocalImport->NextLocalImport = Import;
1221  LastLocalImport = Import;
1222}
1223
1224//===----------------------------------------------------------------------===//
1225//                         Type Sizing and Analysis
1226//===----------------------------------------------------------------------===//
1227
1228/// getFloatTypeSemantics - Return the APFloat 'semantics' for the specified
1229/// scalar floating point type.
1230const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
1231  const BuiltinType *BT = T->getAs<BuiltinType>();
1232  assert(BT && "Not a floating point type!");
1233  switch (BT->getKind()) {
1234  default: llvm_unreachable("Not a floating point type!");
1235  case BuiltinType::Half:       return Target->getHalfFormat();
1236  case BuiltinType::Float:      return Target->getFloatFormat();
1237  case BuiltinType::Double:     return Target->getDoubleFormat();
1238  case BuiltinType::LongDouble: return Target->getLongDoubleFormat();
1239  }
1240}
1241
1242CharUnits ASTContext::getDeclAlign(const Decl *D, bool ForAlignof) const {
1243  unsigned Align = Target->getCharWidth();
1244
1245  bool UseAlignAttrOnly = false;
1246  if (unsigned AlignFromAttr = D->getMaxAlignment()) {
1247    Align = AlignFromAttr;
1248
1249    // __attribute__((aligned)) can increase or decrease alignment
1250    // *except* on a struct or struct member, where it only increases
1251    // alignment unless 'packed' is also specified.
1252    //
1253    // It is an error for alignas to decrease alignment, so we can
1254    // ignore that possibility;  Sema should diagnose it.
1255    if (isa<FieldDecl>(D)) {
1256      UseAlignAttrOnly = D->hasAttr<PackedAttr>() ||
1257        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1258    } else {
1259      UseAlignAttrOnly = true;
1260    }
1261  }
1262  else if (isa<FieldDecl>(D))
1263      UseAlignAttrOnly =
1264        D->hasAttr<PackedAttr>() ||
1265        cast<FieldDecl>(D)->getParent()->hasAttr<PackedAttr>();
1266
1267  // If we're using the align attribute only, just ignore everything
1268  // else about the declaration and its type.
1269  if (UseAlignAttrOnly) {
1270    // do nothing
1271
1272  } else if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) {
1273    QualType T = VD->getType();
1274    if (const ReferenceType* RT = T->getAs<ReferenceType>()) {
1275      if (ForAlignof)
1276        T = RT->getPointeeType();
1277      else
1278        T = getPointerType(RT->getPointeeType());
1279    }
1280    if (!T->isIncompleteType() && !T->isFunctionType()) {
1281      // Adjust alignments of declarations with array type by the
1282      // large-array alignment on the target.
1283      if (const ArrayType *arrayType = getAsArrayType(T)) {
1284        unsigned MinWidth = Target->getLargeArrayMinWidth();
1285        if (!ForAlignof && MinWidth) {
1286          if (isa<VariableArrayType>(arrayType))
1287            Align = std::max(Align, Target->getLargeArrayAlign());
1288          else if (isa<ConstantArrayType>(arrayType) &&
1289                   MinWidth <= getTypeSize(cast<ConstantArrayType>(arrayType)))
1290            Align = std::max(Align, Target->getLargeArrayAlign());
1291        }
1292
1293        // Walk through any array types while we're at it.
1294        T = getBaseElementType(arrayType);
1295      }
1296      Align = std::max(Align, getPreferredTypeAlign(T.getTypePtr()));
1297      if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1298        if (VD->hasGlobalStorage())
1299          Align = std::max(Align, getTargetInfo().getMinGlobalAlign());
1300      }
1301    }
1302
1303    // Fields can be subject to extra alignment constraints, like if
1304    // the field is packed, the struct is packed, or the struct has a
1305    // a max-field-alignment constraint (#pragma pack).  So calculate
1306    // the actual alignment of the field within the struct, and then
1307    // (as we're expected to) constrain that by the alignment of the type.
1308    if (const FieldDecl *Field = dyn_cast<FieldDecl>(VD)) {
1309      const RecordDecl *Parent = Field->getParent();
1310      // We can only produce a sensible answer if the record is valid.
1311      if (!Parent->isInvalidDecl()) {
1312        const ASTRecordLayout &Layout = getASTRecordLayout(Parent);
1313
1314        // Start with the record's overall alignment.
1315        unsigned FieldAlign = toBits(Layout.getAlignment());
1316
1317        // Use the GCD of that and the offset within the record.
1318        uint64_t Offset = Layout.getFieldOffset(Field->getFieldIndex());
1319        if (Offset > 0) {
1320          // Alignment is always a power of 2, so the GCD will be a power of 2,
1321          // which means we get to do this crazy thing instead of Euclid's.
1322          uint64_t LowBitOfOffset = Offset & (~Offset + 1);
1323          if (LowBitOfOffset < FieldAlign)
1324            FieldAlign = static_cast<unsigned>(LowBitOfOffset);
1325        }
1326
1327        Align = std::min(Align, FieldAlign);
1328      }
1329    }
1330  }
1331
1332  return toCharUnitsFromBits(Align);
1333}
1334
1335// getTypeInfoDataSizeInChars - Return the size of a type, in
1336// chars. If the type is a record, its data size is returned.  This is
1337// the size of the memcpy that's performed when assigning this type
1338// using a trivial copy/move assignment operator.
1339std::pair<CharUnits, CharUnits>
1340ASTContext::getTypeInfoDataSizeInChars(QualType T) const {
1341  std::pair<CharUnits, CharUnits> sizeAndAlign = getTypeInfoInChars(T);
1342
1343  // In C++, objects can sometimes be allocated into the tail padding
1344  // of a base-class subobject.  We decide whether that's possible
1345  // during class layout, so here we can just trust the layout results.
1346  if (getLangOpts().CPlusPlus) {
1347    if (const RecordType *RT = T->getAs<RecordType>()) {
1348      const ASTRecordLayout &layout = getASTRecordLayout(RT->getDecl());
1349      sizeAndAlign.first = layout.getDataSize();
1350    }
1351  }
1352
1353  return sizeAndAlign;
1354}
1355
1356/// getConstantArrayInfoInChars - Performing the computation in CharUnits
1357/// instead of in bits prevents overflowing the uint64_t for some large arrays.
1358std::pair<CharUnits, CharUnits>
1359static getConstantArrayInfoInChars(const ASTContext &Context,
1360                                   const ConstantArrayType *CAT) {
1361  std::pair<CharUnits, CharUnits> EltInfo =
1362      Context.getTypeInfoInChars(CAT->getElementType());
1363  uint64_t Size = CAT->getSize().getZExtValue();
1364  assert((Size == 0 || static_cast<uint64_t>(EltInfo.first.getQuantity()) <=
1365              (uint64_t)(-1)/Size) &&
1366         "Overflow in array type char size evaluation");
1367  uint64_t Width = EltInfo.first.getQuantity() * Size;
1368  unsigned Align = EltInfo.second.getQuantity();
1369  Width = llvm::RoundUpToAlignment(Width, Align);
1370  return std::make_pair(CharUnits::fromQuantity(Width),
1371                        CharUnits::fromQuantity(Align));
1372}
1373
1374std::pair<CharUnits, CharUnits>
1375ASTContext::getTypeInfoInChars(const Type *T) const {
1376  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(T))
1377    return getConstantArrayInfoInChars(*this, CAT);
1378  std::pair<uint64_t, unsigned> Info = getTypeInfo(T);
1379  return std::make_pair(toCharUnitsFromBits(Info.first),
1380                        toCharUnitsFromBits(Info.second));
1381}
1382
1383std::pair<CharUnits, CharUnits>
1384ASTContext::getTypeInfoInChars(QualType T) const {
1385  return getTypeInfoInChars(T.getTypePtr());
1386}
1387
1388std::pair<uint64_t, unsigned> ASTContext::getTypeInfo(const Type *T) const {
1389  TypeInfoMap::iterator it = MemoizedTypeInfo.find(T);
1390  if (it != MemoizedTypeInfo.end())
1391    return it->second;
1392
1393  std::pair<uint64_t, unsigned> Info = getTypeInfoImpl(T);
1394  MemoizedTypeInfo.insert(std::make_pair(T, Info));
1395  return Info;
1396}
1397
1398/// getTypeInfoImpl - Return the size of the specified type, in bits.  This
1399/// method does not work on incomplete types.
1400///
1401/// FIXME: Pointers into different addr spaces could have different sizes and
1402/// alignment requirements: getPointerInfo should take an AddrSpace, this
1403/// should take a QualType, &c.
1404std::pair<uint64_t, unsigned>
1405ASTContext::getTypeInfoImpl(const Type *T) const {
1406  uint64_t Width=0;
1407  unsigned Align=8;
1408  switch (T->getTypeClass()) {
1409#define TYPE(Class, Base)
1410#define ABSTRACT_TYPE(Class, Base)
1411#define NON_CANONICAL_TYPE(Class, Base)
1412#define DEPENDENT_TYPE(Class, Base) case Type::Class:
1413#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base)                       \
1414  case Type::Class:                                                            \
1415  assert(!T->isDependentType() && "should not see dependent types here");      \
1416  return getTypeInfo(cast<Class##Type>(T)->desugar().getTypePtr());
1417#include "clang/AST/TypeNodes.def"
1418    llvm_unreachable("Should not see dependent types");
1419
1420  case Type::FunctionNoProto:
1421  case Type::FunctionProto:
1422    // GCC extension: alignof(function) = 32 bits
1423    Width = 0;
1424    Align = 32;
1425    break;
1426
1427  case Type::IncompleteArray:
1428  case Type::VariableArray:
1429    Width = 0;
1430    Align = getTypeAlign(cast<ArrayType>(T)->getElementType());
1431    break;
1432
1433  case Type::ConstantArray: {
1434    const ConstantArrayType *CAT = cast<ConstantArrayType>(T);
1435
1436    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
1437    uint64_t Size = CAT->getSize().getZExtValue();
1438    assert((Size == 0 || EltInfo.first <= (uint64_t)(-1)/Size) &&
1439           "Overflow in array type bit size evaluation");
1440    Width = EltInfo.first*Size;
1441    Align = EltInfo.second;
1442    Width = llvm::RoundUpToAlignment(Width, Align);
1443    break;
1444  }
1445  case Type::ExtVector:
1446  case Type::Vector: {
1447    const VectorType *VT = cast<VectorType>(T);
1448    std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(VT->getElementType());
1449    Width = EltInfo.first*VT->getNumElements();
1450    Align = Width;
1451    // If the alignment is not a power of 2, round up to the next power of 2.
1452    // This happens for non-power-of-2 length vectors.
1453    if (Align & (Align-1)) {
1454      Align = llvm::NextPowerOf2(Align);
1455      Width = llvm::RoundUpToAlignment(Width, Align);
1456    }
1457    // Adjust the alignment based on the target max.
1458    uint64_t TargetVectorAlign = Target->getMaxVectorAlign();
1459    if (TargetVectorAlign && TargetVectorAlign < Align)
1460      Align = TargetVectorAlign;
1461    break;
1462  }
1463
1464  case Type::Builtin:
1465    switch (cast<BuiltinType>(T)->getKind()) {
1466    default: llvm_unreachable("Unknown builtin type!");
1467    case BuiltinType::Void:
1468      // GCC extension: alignof(void) = 8 bits.
1469      Width = 0;
1470      Align = 8;
1471      break;
1472
1473    case BuiltinType::Bool:
1474      Width = Target->getBoolWidth();
1475      Align = Target->getBoolAlign();
1476      break;
1477    case BuiltinType::Char_S:
1478    case BuiltinType::Char_U:
1479    case BuiltinType::UChar:
1480    case BuiltinType::SChar:
1481      Width = Target->getCharWidth();
1482      Align = Target->getCharAlign();
1483      break;
1484    case BuiltinType::WChar_S:
1485    case BuiltinType::WChar_U:
1486      Width = Target->getWCharWidth();
1487      Align = Target->getWCharAlign();
1488      break;
1489    case BuiltinType::Char16:
1490      Width = Target->getChar16Width();
1491      Align = Target->getChar16Align();
1492      break;
1493    case BuiltinType::Char32:
1494      Width = Target->getChar32Width();
1495      Align = Target->getChar32Align();
1496      break;
1497    case BuiltinType::UShort:
1498    case BuiltinType::Short:
1499      Width = Target->getShortWidth();
1500      Align = Target->getShortAlign();
1501      break;
1502    case BuiltinType::UInt:
1503    case BuiltinType::Int:
1504      Width = Target->getIntWidth();
1505      Align = Target->getIntAlign();
1506      break;
1507    case BuiltinType::ULong:
1508    case BuiltinType::Long:
1509      Width = Target->getLongWidth();
1510      Align = Target->getLongAlign();
1511      break;
1512    case BuiltinType::ULongLong:
1513    case BuiltinType::LongLong:
1514      Width = Target->getLongLongWidth();
1515      Align = Target->getLongLongAlign();
1516      break;
1517    case BuiltinType::Int128:
1518    case BuiltinType::UInt128:
1519      Width = 128;
1520      Align = 128; // int128_t is 128-bit aligned on all targets.
1521      break;
1522    case BuiltinType::Half:
1523      Width = Target->getHalfWidth();
1524      Align = Target->getHalfAlign();
1525      break;
1526    case BuiltinType::Float:
1527      Width = Target->getFloatWidth();
1528      Align = Target->getFloatAlign();
1529      break;
1530    case BuiltinType::Double:
1531      Width = Target->getDoubleWidth();
1532      Align = Target->getDoubleAlign();
1533      break;
1534    case BuiltinType::LongDouble:
1535      Width = Target->getLongDoubleWidth();
1536      Align = Target->getLongDoubleAlign();
1537      break;
1538    case BuiltinType::NullPtr:
1539      Width = Target->getPointerWidth(0); // C++ 3.9.1p11: sizeof(nullptr_t)
1540      Align = Target->getPointerAlign(0); //   == sizeof(void*)
1541      break;
1542    case BuiltinType::ObjCId:
1543    case BuiltinType::ObjCClass:
1544    case BuiltinType::ObjCSel:
1545      Width = Target->getPointerWidth(0);
1546      Align = Target->getPointerAlign(0);
1547      break;
1548    case BuiltinType::OCLSampler:
1549      // Samplers are modeled as integers.
1550      Width = Target->getIntWidth();
1551      Align = Target->getIntAlign();
1552      break;
1553    case BuiltinType::OCLEvent:
1554    case BuiltinType::OCLImage1d:
1555    case BuiltinType::OCLImage1dArray:
1556    case BuiltinType::OCLImage1dBuffer:
1557    case BuiltinType::OCLImage2d:
1558    case BuiltinType::OCLImage2dArray:
1559    case BuiltinType::OCLImage3d:
1560      // Currently these types are pointers to opaque types.
1561      Width = Target->getPointerWidth(0);
1562      Align = Target->getPointerAlign(0);
1563      break;
1564    }
1565    break;
1566  case Type::ObjCObjectPointer:
1567    Width = Target->getPointerWidth(0);
1568    Align = Target->getPointerAlign(0);
1569    break;
1570  case Type::BlockPointer: {
1571    unsigned AS = getTargetAddressSpace(
1572        cast<BlockPointerType>(T)->getPointeeType());
1573    Width = Target->getPointerWidth(AS);
1574    Align = Target->getPointerAlign(AS);
1575    break;
1576  }
1577  case Type::LValueReference:
1578  case Type::RValueReference: {
1579    // alignof and sizeof should never enter this code path here, so we go
1580    // the pointer route.
1581    unsigned AS = getTargetAddressSpace(
1582        cast<ReferenceType>(T)->getPointeeType());
1583    Width = Target->getPointerWidth(AS);
1584    Align = Target->getPointerAlign(AS);
1585    break;
1586  }
1587  case Type::Pointer: {
1588    unsigned AS = getTargetAddressSpace(cast<PointerType>(T)->getPointeeType());
1589    Width = Target->getPointerWidth(AS);
1590    Align = Target->getPointerAlign(AS);
1591    break;
1592  }
1593  case Type::MemberPointer: {
1594    const MemberPointerType *MPT = cast<MemberPointerType>(T);
1595    llvm::tie(Width, Align) = ABI->getMemberPointerWidthAndAlign(MPT);
1596    break;
1597  }
1598  case Type::Complex: {
1599    // Complex types have the same alignment as their elements, but twice the
1600    // size.
1601    std::pair<uint64_t, unsigned> EltInfo =
1602      getTypeInfo(cast<ComplexType>(T)->getElementType());
1603    Width = EltInfo.first*2;
1604    Align = EltInfo.second;
1605    break;
1606  }
1607  case Type::ObjCObject:
1608    return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
1609  case Type::Decayed:
1610    return getTypeInfo(cast<DecayedType>(T)->getDecayedType().getTypePtr());
1611  case Type::ObjCInterface: {
1612    const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
1613    const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
1614    Width = toBits(Layout.getSize());
1615    Align = toBits(Layout.getAlignment());
1616    break;
1617  }
1618  case Type::Record:
1619  case Type::Enum: {
1620    const TagType *TT = cast<TagType>(T);
1621
1622    if (TT->getDecl()->isInvalidDecl()) {
1623      Width = 8;
1624      Align = 8;
1625      break;
1626    }
1627
1628    if (const EnumType *ET = dyn_cast<EnumType>(TT))
1629      return getTypeInfo(ET->getDecl()->getIntegerType());
1630
1631    const RecordType *RT = cast<RecordType>(TT);
1632    const ASTRecordLayout &Layout = getASTRecordLayout(RT->getDecl());
1633    Width = toBits(Layout.getSize());
1634    Align = toBits(Layout.getAlignment());
1635    break;
1636  }
1637
1638  case Type::SubstTemplateTypeParm:
1639    return getTypeInfo(cast<SubstTemplateTypeParmType>(T)->
1640                       getReplacementType().getTypePtr());
1641
1642  case Type::Auto: {
1643    const AutoType *A = cast<AutoType>(T);
1644    assert(!A->getDeducedType().isNull() &&
1645           "cannot request the size of an undeduced or dependent auto type");
1646    return getTypeInfo(A->getDeducedType().getTypePtr());
1647  }
1648
1649  case Type::Paren:
1650    return getTypeInfo(cast<ParenType>(T)->getInnerType().getTypePtr());
1651
1652  case Type::Typedef: {
1653    const TypedefNameDecl *Typedef = cast<TypedefType>(T)->getDecl();
1654    std::pair<uint64_t, unsigned> Info
1655      = getTypeInfo(Typedef->getUnderlyingType().getTypePtr());
1656    // If the typedef has an aligned attribute on it, it overrides any computed
1657    // alignment we have.  This violates the GCC documentation (which says that
1658    // attribute(aligned) can only round up) but matches its implementation.
1659    if (unsigned AttrAlign = Typedef->getMaxAlignment())
1660      Align = AttrAlign;
1661    else
1662      Align = Info.second;
1663    Width = Info.first;
1664    break;
1665  }
1666
1667  case Type::Elaborated:
1668    return getTypeInfo(cast<ElaboratedType>(T)->getNamedType().getTypePtr());
1669
1670  case Type::Attributed:
1671    return getTypeInfo(
1672                  cast<AttributedType>(T)->getEquivalentType().getTypePtr());
1673
1674  case Type::Atomic: {
1675    // Start with the base type information.
1676    std::pair<uint64_t, unsigned> Info
1677      = getTypeInfo(cast<AtomicType>(T)->getValueType());
1678    Width = Info.first;
1679    Align = Info.second;
1680
1681    // If the size of the type doesn't exceed the platform's max
1682    // atomic promotion width, make the size and alignment more
1683    // favorable to atomic operations:
1684    if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth()) {
1685      // Round the size up to a power of 2.
1686      if (!llvm::isPowerOf2_64(Width))
1687        Width = llvm::NextPowerOf2(Width);
1688
1689      // Set the alignment equal to the size.
1690      Align = static_cast<unsigned>(Width);
1691    }
1692  }
1693
1694  }
1695
1696  assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
1697  return std::make_pair(Width, Align);
1698}
1699
1700/// toCharUnitsFromBits - Convert a size in bits to a size in characters.
1701CharUnits ASTContext::toCharUnitsFromBits(int64_t BitSize) const {
1702  return CharUnits::fromQuantity(BitSize / getCharWidth());
1703}
1704
1705/// toBits - Convert a size in characters to a size in characters.
1706int64_t ASTContext::toBits(CharUnits CharSize) const {
1707  return CharSize.getQuantity() * getCharWidth();
1708}
1709
1710/// getTypeSizeInChars - Return the size of the specified type, in characters.
1711/// This method does not work on incomplete types.
1712CharUnits ASTContext::getTypeSizeInChars(QualType T) const {
1713  return getTypeInfoInChars(T).first;
1714}
1715CharUnits ASTContext::getTypeSizeInChars(const Type *T) const {
1716  return getTypeInfoInChars(T).first;
1717}
1718
1719/// getTypeAlignInChars - Return the ABI-specified alignment of a type, in
1720/// characters. This method does not work on incomplete types.
1721CharUnits ASTContext::getTypeAlignInChars(QualType T) const {
1722  return toCharUnitsFromBits(getTypeAlign(T));
1723}
1724CharUnits ASTContext::getTypeAlignInChars(const Type *T) const {
1725  return toCharUnitsFromBits(getTypeAlign(T));
1726}
1727
1728/// getPreferredTypeAlign - Return the "preferred" alignment of the specified
1729/// type for the current target in bits.  This can be different than the ABI
1730/// alignment in cases where it is beneficial for performance to overalign
1731/// a data type.
1732unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
1733  unsigned ABIAlign = getTypeAlign(T);
1734
1735  // Double and long long should be naturally aligned if possible.
1736  if (const ComplexType* CT = T->getAs<ComplexType>())
1737    T = CT->getElementType().getTypePtr();
1738  if (T->isSpecificBuiltinType(BuiltinType::Double) ||
1739      T->isSpecificBuiltinType(BuiltinType::LongLong) ||
1740      T->isSpecificBuiltinType(BuiltinType::ULongLong))
1741    return std::max(ABIAlign, (unsigned)getTypeSize(T));
1742
1743  return ABIAlign;
1744}
1745
1746/// getAlignOfGlobalVar - Return the alignment in bits that should be given
1747/// to a global variable of the specified type.
1748unsigned ASTContext::getAlignOfGlobalVar(QualType T) const {
1749  return std::max(getTypeAlign(T), getTargetInfo().getMinGlobalAlign());
1750}
1751
1752/// getAlignOfGlobalVarInChars - Return the alignment in characters that
1753/// should be given to a global variable of the specified type.
1754CharUnits ASTContext::getAlignOfGlobalVarInChars(QualType T) const {
1755  return toCharUnitsFromBits(getAlignOfGlobalVar(T));
1756}
1757
1758/// DeepCollectObjCIvars -
1759/// This routine first collects all declared, but not synthesized, ivars in
1760/// super class and then collects all ivars, including those synthesized for
1761/// current class. This routine is used for implementation of current class
1762/// when all ivars, declared and synthesized are known.
1763///
1764void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
1765                                      bool leafClass,
1766                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
1767  if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
1768    DeepCollectObjCIvars(SuperClass, false, Ivars);
1769  if (!leafClass) {
1770    for (ObjCInterfaceDecl::ivar_iterator I = OI->ivar_begin(),
1771         E = OI->ivar_end(); I != E; ++I)
1772      Ivars.push_back(*I);
1773  } else {
1774    ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
1775    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv;
1776         Iv= Iv->getNextIvar())
1777      Ivars.push_back(Iv);
1778  }
1779}
1780
1781/// CollectInheritedProtocols - Collect all protocols in current class and
1782/// those inherited by it.
1783void ASTContext::CollectInheritedProtocols(const Decl *CDecl,
1784                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols) {
1785  if (const ObjCInterfaceDecl *OI = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
1786    // We can use protocol_iterator here instead of
1787    // all_referenced_protocol_iterator since we are walking all categories.
1788    for (ObjCInterfaceDecl::all_protocol_iterator P = OI->all_referenced_protocol_begin(),
1789         PE = OI->all_referenced_protocol_end(); P != PE; ++P) {
1790      ObjCProtocolDecl *Proto = (*P);
1791      Protocols.insert(Proto->getCanonicalDecl());
1792      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1793           PE = Proto->protocol_end(); P != PE; ++P) {
1794        Protocols.insert((*P)->getCanonicalDecl());
1795        CollectInheritedProtocols(*P, Protocols);
1796      }
1797    }
1798
1799    // Categories of this Interface.
1800    for (ObjCInterfaceDecl::visible_categories_iterator
1801           Cat = OI->visible_categories_begin(),
1802           CatEnd = OI->visible_categories_end();
1803         Cat != CatEnd; ++Cat) {
1804      CollectInheritedProtocols(*Cat, Protocols);
1805    }
1806
1807    if (ObjCInterfaceDecl *SD = OI->getSuperClass())
1808      while (SD) {
1809        CollectInheritedProtocols(SD, Protocols);
1810        SD = SD->getSuperClass();
1811      }
1812  } else if (const ObjCCategoryDecl *OC = dyn_cast<ObjCCategoryDecl>(CDecl)) {
1813    for (ObjCCategoryDecl::protocol_iterator P = OC->protocol_begin(),
1814         PE = OC->protocol_end(); P != PE; ++P) {
1815      ObjCProtocolDecl *Proto = (*P);
1816      Protocols.insert(Proto->getCanonicalDecl());
1817      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1818           PE = Proto->protocol_end(); P != PE; ++P)
1819        CollectInheritedProtocols(*P, Protocols);
1820    }
1821  } else if (const ObjCProtocolDecl *OP = dyn_cast<ObjCProtocolDecl>(CDecl)) {
1822    for (ObjCProtocolDecl::protocol_iterator P = OP->protocol_begin(),
1823         PE = OP->protocol_end(); P != PE; ++P) {
1824      ObjCProtocolDecl *Proto = (*P);
1825      Protocols.insert(Proto->getCanonicalDecl());
1826      for (ObjCProtocolDecl::protocol_iterator P = Proto->protocol_begin(),
1827           PE = Proto->protocol_end(); P != PE; ++P)
1828        CollectInheritedProtocols(*P, Protocols);
1829    }
1830  }
1831}
1832
1833unsigned ASTContext::CountNonClassIvars(const ObjCInterfaceDecl *OI) const {
1834  unsigned count = 0;
1835  // Count ivars declared in class extension.
1836  for (ObjCInterfaceDecl::known_extensions_iterator
1837         Ext = OI->known_extensions_begin(),
1838         ExtEnd = OI->known_extensions_end();
1839       Ext != ExtEnd; ++Ext) {
1840    count += Ext->ivar_size();
1841  }
1842
1843  // Count ivar defined in this class's implementation.  This
1844  // includes synthesized ivars.
1845  if (ObjCImplementationDecl *ImplDecl = OI->getImplementation())
1846    count += ImplDecl->ivar_size();
1847
1848  return count;
1849}
1850
1851bool ASTContext::isSentinelNullExpr(const Expr *E) {
1852  if (!E)
1853    return false;
1854
1855  // nullptr_t is always treated as null.
1856  if (E->getType()->isNullPtrType()) return true;
1857
1858  if (E->getType()->isAnyPointerType() &&
1859      E->IgnoreParenCasts()->isNullPointerConstant(*this,
1860                                                Expr::NPC_ValueDependentIsNull))
1861    return true;
1862
1863  // Unfortunately, __null has type 'int'.
1864  if (isa<GNUNullExpr>(E)) return true;
1865
1866  return false;
1867}
1868
1869/// \brief Get the implementation of ObjCInterfaceDecl,or NULL if none exists.
1870ObjCImplementationDecl *ASTContext::getObjCImplementation(ObjCInterfaceDecl *D) {
1871  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1872    I = ObjCImpls.find(D);
1873  if (I != ObjCImpls.end())
1874    return cast<ObjCImplementationDecl>(I->second);
1875  return 0;
1876}
1877/// \brief Get the implementation of ObjCCategoryDecl, or NULL if none exists.
1878ObjCCategoryImplDecl *ASTContext::getObjCImplementation(ObjCCategoryDecl *D) {
1879  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*>::iterator
1880    I = ObjCImpls.find(D);
1881  if (I != ObjCImpls.end())
1882    return cast<ObjCCategoryImplDecl>(I->second);
1883  return 0;
1884}
1885
1886/// \brief Set the implementation of ObjCInterfaceDecl.
1887void ASTContext::setObjCImplementation(ObjCInterfaceDecl *IFaceD,
1888                           ObjCImplementationDecl *ImplD) {
1889  assert(IFaceD && ImplD && "Passed null params");
1890  ObjCImpls[IFaceD] = ImplD;
1891}
1892/// \brief Set the implementation of ObjCCategoryDecl.
1893void ASTContext::setObjCImplementation(ObjCCategoryDecl *CatD,
1894                           ObjCCategoryImplDecl *ImplD) {
1895  assert(CatD && ImplD && "Passed null params");
1896  ObjCImpls[CatD] = ImplD;
1897}
1898
1899const ObjCInterfaceDecl *ASTContext::getObjContainingInterface(
1900                                              const NamedDecl *ND) const {
1901  if (const ObjCInterfaceDecl *ID =
1902          dyn_cast<ObjCInterfaceDecl>(ND->getDeclContext()))
1903    return ID;
1904  if (const ObjCCategoryDecl *CD =
1905          dyn_cast<ObjCCategoryDecl>(ND->getDeclContext()))
1906    return CD->getClassInterface();
1907  if (const ObjCImplDecl *IMD =
1908          dyn_cast<ObjCImplDecl>(ND->getDeclContext()))
1909    return IMD->getClassInterface();
1910
1911  return 0;
1912}
1913
1914/// \brief Get the copy initialization expression of VarDecl,or NULL if
1915/// none exists.
1916Expr *ASTContext::getBlockVarCopyInits(const VarDecl*VD) {
1917  assert(VD && "Passed null params");
1918  assert(VD->hasAttr<BlocksAttr>() &&
1919         "getBlockVarCopyInits - not __block var");
1920  llvm::DenseMap<const VarDecl*, Expr*>::iterator
1921    I = BlockVarCopyInits.find(VD);
1922  return (I != BlockVarCopyInits.end()) ? cast<Expr>(I->second) : 0;
1923}
1924
1925/// \brief Set the copy inialization expression of a block var decl.
1926void ASTContext::setBlockVarCopyInits(VarDecl*VD, Expr* Init) {
1927  assert(VD && Init && "Passed null params");
1928  assert(VD->hasAttr<BlocksAttr>() &&
1929         "setBlockVarCopyInits - not __block var");
1930  BlockVarCopyInits[VD] = Init;
1931}
1932
1933TypeSourceInfo *ASTContext::CreateTypeSourceInfo(QualType T,
1934                                                 unsigned DataSize) const {
1935  if (!DataSize)
1936    DataSize = TypeLoc::getFullDataSizeForType(T);
1937  else
1938    assert(DataSize == TypeLoc::getFullDataSizeForType(T) &&
1939           "incorrect data size provided to CreateTypeSourceInfo!");
1940
1941  TypeSourceInfo *TInfo =
1942    (TypeSourceInfo*)BumpAlloc.Allocate(sizeof(TypeSourceInfo) + DataSize, 8);
1943  new (TInfo) TypeSourceInfo(T);
1944  return TInfo;
1945}
1946
1947TypeSourceInfo *ASTContext::getTrivialTypeSourceInfo(QualType T,
1948                                                     SourceLocation L) const {
1949  TypeSourceInfo *DI = CreateTypeSourceInfo(T);
1950  DI->getTypeLoc().initialize(const_cast<ASTContext &>(*this), L);
1951  return DI;
1952}
1953
1954const ASTRecordLayout &
1955ASTContext::getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const {
1956  return getObjCLayout(D, 0);
1957}
1958
1959const ASTRecordLayout &
1960ASTContext::getASTObjCImplementationLayout(
1961                                        const ObjCImplementationDecl *D) const {
1962  return getObjCLayout(D->getClassInterface(), D);
1963}
1964
1965//===----------------------------------------------------------------------===//
1966//                   Type creation/memoization methods
1967//===----------------------------------------------------------------------===//
1968
1969QualType
1970ASTContext::getExtQualType(const Type *baseType, Qualifiers quals) const {
1971  unsigned fastQuals = quals.getFastQualifiers();
1972  quals.removeFastQualifiers();
1973
1974  // Check if we've already instantiated this type.
1975  llvm::FoldingSetNodeID ID;
1976  ExtQuals::Profile(ID, baseType, quals);
1977  void *insertPos = 0;
1978  if (ExtQuals *eq = ExtQualNodes.FindNodeOrInsertPos(ID, insertPos)) {
1979    assert(eq->getQualifiers() == quals);
1980    return QualType(eq, fastQuals);
1981  }
1982
1983  // If the base type is not canonical, make the appropriate canonical type.
1984  QualType canon;
1985  if (!baseType->isCanonicalUnqualified()) {
1986    SplitQualType canonSplit = baseType->getCanonicalTypeInternal().split();
1987    canonSplit.Quals.addConsistentQualifiers(quals);
1988    canon = getExtQualType(canonSplit.Ty, canonSplit.Quals);
1989
1990    // Re-find the insert position.
1991    (void) ExtQualNodes.FindNodeOrInsertPos(ID, insertPos);
1992  }
1993
1994  ExtQuals *eq = new (*this, TypeAlignment) ExtQuals(baseType, canon, quals);
1995  ExtQualNodes.InsertNode(eq, insertPos);
1996  return QualType(eq, fastQuals);
1997}
1998
1999QualType
2000ASTContext::getAddrSpaceQualType(QualType T, unsigned AddressSpace) const {
2001  QualType CanT = getCanonicalType(T);
2002  if (CanT.getAddressSpace() == AddressSpace)
2003    return T;
2004
2005  // If we are composing extended qualifiers together, merge together
2006  // into one ExtQuals node.
2007  QualifierCollector Quals;
2008  const Type *TypeNode = Quals.strip(T);
2009
2010  // If this type already has an address space specified, it cannot get
2011  // another one.
2012  assert(!Quals.hasAddressSpace() &&
2013         "Type cannot be in multiple addr spaces!");
2014  Quals.addAddressSpace(AddressSpace);
2015
2016  return getExtQualType(TypeNode, Quals);
2017}
2018
2019QualType ASTContext::getObjCGCQualType(QualType T,
2020                                       Qualifiers::GC GCAttr) const {
2021  QualType CanT = getCanonicalType(T);
2022  if (CanT.getObjCGCAttr() == GCAttr)
2023    return T;
2024
2025  if (const PointerType *ptr = T->getAs<PointerType>()) {
2026    QualType Pointee = ptr->getPointeeType();
2027    if (Pointee->isAnyPointerType()) {
2028      QualType ResultType = getObjCGCQualType(Pointee, GCAttr);
2029      return getPointerType(ResultType);
2030    }
2031  }
2032
2033  // If we are composing extended qualifiers together, merge together
2034  // into one ExtQuals node.
2035  QualifierCollector Quals;
2036  const Type *TypeNode = Quals.strip(T);
2037
2038  // If this type already has an ObjCGC specified, it cannot get
2039  // another one.
2040  assert(!Quals.hasObjCGCAttr() &&
2041         "Type cannot have multiple ObjCGCs!");
2042  Quals.addObjCGCAttr(GCAttr);
2043
2044  return getExtQualType(TypeNode, Quals);
2045}
2046
2047const FunctionType *ASTContext::adjustFunctionType(const FunctionType *T,
2048                                                   FunctionType::ExtInfo Info) {
2049  if (T->getExtInfo() == Info)
2050    return T;
2051
2052  QualType Result;
2053  if (const FunctionNoProtoType *FNPT = dyn_cast<FunctionNoProtoType>(T)) {
2054    Result = getFunctionNoProtoType(FNPT->getResultType(), Info);
2055  } else {
2056    const FunctionProtoType *FPT = cast<FunctionProtoType>(T);
2057    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
2058    EPI.ExtInfo = Info;
2059    Result = getFunctionType(FPT->getResultType(), FPT->getArgTypes(), EPI);
2060  }
2061
2062  return cast<FunctionType>(Result.getTypePtr());
2063}
2064
2065void ASTContext::adjustDeducedFunctionResultType(FunctionDecl *FD,
2066                                                 QualType ResultType) {
2067  FD = FD->getMostRecentDecl();
2068  while (true) {
2069    const FunctionProtoType *FPT = FD->getType()->castAs<FunctionProtoType>();
2070    FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
2071    FD->setType(getFunctionType(ResultType, FPT->getArgTypes(), EPI));
2072    if (FunctionDecl *Next = FD->getPreviousDecl())
2073      FD = Next;
2074    else
2075      break;
2076  }
2077  if (ASTMutationListener *L = getASTMutationListener())
2078    L->DeducedReturnType(FD, ResultType);
2079}
2080
2081/// getComplexType - Return the uniqued reference to the type for a complex
2082/// number with the specified element type.
2083QualType ASTContext::getComplexType(QualType T) const {
2084  // Unique pointers, to guarantee there is only one pointer of a particular
2085  // structure.
2086  llvm::FoldingSetNodeID ID;
2087  ComplexType::Profile(ID, T);
2088
2089  void *InsertPos = 0;
2090  if (ComplexType *CT = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos))
2091    return QualType(CT, 0);
2092
2093  // If the pointee type isn't canonical, this won't be a canonical type either,
2094  // so fill in the canonical type field.
2095  QualType Canonical;
2096  if (!T.isCanonical()) {
2097    Canonical = getComplexType(getCanonicalType(T));
2098
2099    // Get the new insert position for the node we care about.
2100    ComplexType *NewIP = ComplexTypes.FindNodeOrInsertPos(ID, InsertPos);
2101    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2102  }
2103  ComplexType *New = new (*this, TypeAlignment) ComplexType(T, Canonical);
2104  Types.push_back(New);
2105  ComplexTypes.InsertNode(New, InsertPos);
2106  return QualType(New, 0);
2107}
2108
2109/// getPointerType - Return the uniqued reference to the type for a pointer to
2110/// the specified type.
2111QualType ASTContext::getPointerType(QualType T) const {
2112  // Unique pointers, to guarantee there is only one pointer of a particular
2113  // structure.
2114  llvm::FoldingSetNodeID ID;
2115  PointerType::Profile(ID, T);
2116
2117  void *InsertPos = 0;
2118  if (PointerType *PT = PointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2119    return QualType(PT, 0);
2120
2121  // If the pointee type isn't canonical, this won't be a canonical type either,
2122  // so fill in the canonical type field.
2123  QualType Canonical;
2124  if (!T.isCanonical()) {
2125    Canonical = getPointerType(getCanonicalType(T));
2126
2127    // Get the new insert position for the node we care about.
2128    PointerType *NewIP = PointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2129    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2130  }
2131  PointerType *New = new (*this, TypeAlignment) PointerType(T, Canonical);
2132  Types.push_back(New);
2133  PointerTypes.InsertNode(New, InsertPos);
2134  return QualType(New, 0);
2135}
2136
2137QualType ASTContext::getDecayedType(QualType T) const {
2138  assert((T->isArrayType() || T->isFunctionType()) && "T does not decay");
2139
2140  llvm::FoldingSetNodeID ID;
2141  DecayedType::Profile(ID, T);
2142  void *InsertPos = 0;
2143  if (DecayedType *DT = DecayedTypes.FindNodeOrInsertPos(ID, InsertPos))
2144    return QualType(DT, 0);
2145
2146  QualType Decayed;
2147
2148  // C99 6.7.5.3p7:
2149  //   A declaration of a parameter as "array of type" shall be
2150  //   adjusted to "qualified pointer to type", where the type
2151  //   qualifiers (if any) are those specified within the [ and ] of
2152  //   the array type derivation.
2153  if (T->isArrayType())
2154    Decayed = getArrayDecayedType(T);
2155
2156  // C99 6.7.5.3p8:
2157  //   A declaration of a parameter as "function returning type"
2158  //   shall be adjusted to "pointer to function returning type", as
2159  //   in 6.3.2.1.
2160  if (T->isFunctionType())
2161    Decayed = getPointerType(T);
2162
2163  QualType Canonical = getCanonicalType(Decayed);
2164
2165  // Get the new insert position for the node we care about.
2166  DecayedType *NewIP = DecayedTypes.FindNodeOrInsertPos(ID, InsertPos);
2167  assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2168
2169  DecayedType *New =
2170      new (*this, TypeAlignment) DecayedType(T, Decayed, Canonical);
2171  Types.push_back(New);
2172  DecayedTypes.InsertNode(New, InsertPos);
2173  return QualType(New, 0);
2174}
2175
2176/// getBlockPointerType - Return the uniqued reference to the type for
2177/// a pointer to the specified block.
2178QualType ASTContext::getBlockPointerType(QualType T) const {
2179  assert(T->isFunctionType() && "block of function types only");
2180  // Unique pointers, to guarantee there is only one block of a particular
2181  // structure.
2182  llvm::FoldingSetNodeID ID;
2183  BlockPointerType::Profile(ID, T);
2184
2185  void *InsertPos = 0;
2186  if (BlockPointerType *PT =
2187        BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2188    return QualType(PT, 0);
2189
2190  // If the block pointee type isn't canonical, this won't be a canonical
2191  // type either so fill in the canonical type field.
2192  QualType Canonical;
2193  if (!T.isCanonical()) {
2194    Canonical = getBlockPointerType(getCanonicalType(T));
2195
2196    // Get the new insert position for the node we care about.
2197    BlockPointerType *NewIP =
2198      BlockPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2199    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2200  }
2201  BlockPointerType *New
2202    = new (*this, TypeAlignment) BlockPointerType(T, Canonical);
2203  Types.push_back(New);
2204  BlockPointerTypes.InsertNode(New, InsertPos);
2205  return QualType(New, 0);
2206}
2207
2208/// getLValueReferenceType - Return the uniqued reference to the type for an
2209/// lvalue reference to the specified type.
2210QualType
2211ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
2212  assert(getCanonicalType(T) != OverloadTy &&
2213         "Unresolved overloaded function type");
2214
2215  // Unique pointers, to guarantee there is only one pointer of a particular
2216  // structure.
2217  llvm::FoldingSetNodeID ID;
2218  ReferenceType::Profile(ID, T, SpelledAsLValue);
2219
2220  void *InsertPos = 0;
2221  if (LValueReferenceType *RT =
2222        LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
2223    return QualType(RT, 0);
2224
2225  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
2226
2227  // If the referencee type isn't canonical, this won't be a canonical type
2228  // either, so fill in the canonical type field.
2229  QualType Canonical;
2230  if (!SpelledAsLValue || InnerRef || !T.isCanonical()) {
2231    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
2232    Canonical = getLValueReferenceType(getCanonicalType(PointeeType));
2233
2234    // Get the new insert position for the node we care about.
2235    LValueReferenceType *NewIP =
2236      LValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
2237    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2238  }
2239
2240  LValueReferenceType *New
2241    = new (*this, TypeAlignment) LValueReferenceType(T, Canonical,
2242                                                     SpelledAsLValue);
2243  Types.push_back(New);
2244  LValueReferenceTypes.InsertNode(New, InsertPos);
2245
2246  return QualType(New, 0);
2247}
2248
2249/// getRValueReferenceType - Return the uniqued reference to the type for an
2250/// rvalue reference to the specified type.
2251QualType ASTContext::getRValueReferenceType(QualType T) const {
2252  // Unique pointers, to guarantee there is only one pointer of a particular
2253  // structure.
2254  llvm::FoldingSetNodeID ID;
2255  ReferenceType::Profile(ID, T, false);
2256
2257  void *InsertPos = 0;
2258  if (RValueReferenceType *RT =
2259        RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos))
2260    return QualType(RT, 0);
2261
2262  const ReferenceType *InnerRef = T->getAs<ReferenceType>();
2263
2264  // If the referencee type isn't canonical, this won't be a canonical type
2265  // either, so fill in the canonical type field.
2266  QualType Canonical;
2267  if (InnerRef || !T.isCanonical()) {
2268    QualType PointeeType = (InnerRef ? InnerRef->getPointeeType() : T);
2269    Canonical = getRValueReferenceType(getCanonicalType(PointeeType));
2270
2271    // Get the new insert position for the node we care about.
2272    RValueReferenceType *NewIP =
2273      RValueReferenceTypes.FindNodeOrInsertPos(ID, InsertPos);
2274    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2275  }
2276
2277  RValueReferenceType *New
2278    = new (*this, TypeAlignment) RValueReferenceType(T, Canonical);
2279  Types.push_back(New);
2280  RValueReferenceTypes.InsertNode(New, InsertPos);
2281  return QualType(New, 0);
2282}
2283
2284/// getMemberPointerType - Return the uniqued reference to the type for a
2285/// member pointer to the specified type, in the specified class.
2286QualType ASTContext::getMemberPointerType(QualType T, const Type *Cls) const {
2287  // Unique pointers, to guarantee there is only one pointer of a particular
2288  // structure.
2289  llvm::FoldingSetNodeID ID;
2290  MemberPointerType::Profile(ID, T, Cls);
2291
2292  void *InsertPos = 0;
2293  if (MemberPointerType *PT =
2294      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
2295    return QualType(PT, 0);
2296
2297  // If the pointee or class type isn't canonical, this won't be a canonical
2298  // type either, so fill in the canonical type field.
2299  QualType Canonical;
2300  if (!T.isCanonical() || !Cls->isCanonicalUnqualified()) {
2301    Canonical = getMemberPointerType(getCanonicalType(T),getCanonicalType(Cls));
2302
2303    // Get the new insert position for the node we care about.
2304    MemberPointerType *NewIP =
2305      MemberPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
2306    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2307  }
2308  MemberPointerType *New
2309    = new (*this, TypeAlignment) MemberPointerType(T, Cls, Canonical);
2310  Types.push_back(New);
2311  MemberPointerTypes.InsertNode(New, InsertPos);
2312  return QualType(New, 0);
2313}
2314
2315/// getConstantArrayType - Return the unique reference to the type for an
2316/// array of the specified element type.
2317QualType ASTContext::getConstantArrayType(QualType EltTy,
2318                                          const llvm::APInt &ArySizeIn,
2319                                          ArrayType::ArraySizeModifier ASM,
2320                                          unsigned IndexTypeQuals) const {
2321  assert((EltTy->isDependentType() ||
2322          EltTy->isIncompleteType() || EltTy->isConstantSizeType()) &&
2323         "Constant array of VLAs is illegal!");
2324
2325  // Convert the array size into a canonical width matching the pointer size for
2326  // the target.
2327  llvm::APInt ArySize(ArySizeIn);
2328  ArySize =
2329    ArySize.zextOrTrunc(Target->getPointerWidth(getTargetAddressSpace(EltTy)));
2330
2331  llvm::FoldingSetNodeID ID;
2332  ConstantArrayType::Profile(ID, EltTy, ArySize, ASM, IndexTypeQuals);
2333
2334  void *InsertPos = 0;
2335  if (ConstantArrayType *ATP =
2336      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
2337    return QualType(ATP, 0);
2338
2339  // If the element type isn't canonical or has qualifiers, this won't
2340  // be a canonical type either, so fill in the canonical type field.
2341  QualType Canon;
2342  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2343    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2344    Canon = getConstantArrayType(QualType(canonSplit.Ty, 0), ArySize,
2345                                 ASM, IndexTypeQuals);
2346    Canon = getQualifiedType(Canon, canonSplit.Quals);
2347
2348    // Get the new insert position for the node we care about.
2349    ConstantArrayType *NewIP =
2350      ConstantArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
2351    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2352  }
2353
2354  ConstantArrayType *New = new(*this,TypeAlignment)
2355    ConstantArrayType(EltTy, Canon, ArySize, ASM, IndexTypeQuals);
2356  ConstantArrayTypes.InsertNode(New, InsertPos);
2357  Types.push_back(New);
2358  return QualType(New, 0);
2359}
2360
2361/// getVariableArrayDecayedType - Turns the given type, which may be
2362/// variably-modified, into the corresponding type with all the known
2363/// sizes replaced with [*].
2364QualType ASTContext::getVariableArrayDecayedType(QualType type) const {
2365  // Vastly most common case.
2366  if (!type->isVariablyModifiedType()) return type;
2367
2368  QualType result;
2369
2370  SplitQualType split = type.getSplitDesugaredType();
2371  const Type *ty = split.Ty;
2372  switch (ty->getTypeClass()) {
2373#define TYPE(Class, Base)
2374#define ABSTRACT_TYPE(Class, Base)
2375#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
2376#include "clang/AST/TypeNodes.def"
2377    llvm_unreachable("didn't desugar past all non-canonical types?");
2378
2379  // These types should never be variably-modified.
2380  case Type::Builtin:
2381  case Type::Complex:
2382  case Type::Vector:
2383  case Type::ExtVector:
2384  case Type::DependentSizedExtVector:
2385  case Type::ObjCObject:
2386  case Type::ObjCInterface:
2387  case Type::ObjCObjectPointer:
2388  case Type::Record:
2389  case Type::Enum:
2390  case Type::UnresolvedUsing:
2391  case Type::TypeOfExpr:
2392  case Type::TypeOf:
2393  case Type::Decltype:
2394  case Type::UnaryTransform:
2395  case Type::DependentName:
2396  case Type::InjectedClassName:
2397  case Type::TemplateSpecialization:
2398  case Type::DependentTemplateSpecialization:
2399  case Type::TemplateTypeParm:
2400  case Type::SubstTemplateTypeParmPack:
2401  case Type::Auto:
2402  case Type::PackExpansion:
2403    llvm_unreachable("type should never be variably-modified");
2404
2405  // These types can be variably-modified but should never need to
2406  // further decay.
2407  case Type::FunctionNoProto:
2408  case Type::FunctionProto:
2409  case Type::BlockPointer:
2410  case Type::MemberPointer:
2411    return type;
2412
2413  // These types can be variably-modified.  All these modifications
2414  // preserve structure except as noted by comments.
2415  // TODO: if we ever care about optimizing VLAs, there are no-op
2416  // optimizations available here.
2417  case Type::Pointer:
2418    result = getPointerType(getVariableArrayDecayedType(
2419                              cast<PointerType>(ty)->getPointeeType()));
2420    break;
2421
2422  case Type::LValueReference: {
2423    const LValueReferenceType *lv = cast<LValueReferenceType>(ty);
2424    result = getLValueReferenceType(
2425                 getVariableArrayDecayedType(lv->getPointeeType()),
2426                                    lv->isSpelledAsLValue());
2427    break;
2428  }
2429
2430  case Type::RValueReference: {
2431    const RValueReferenceType *lv = cast<RValueReferenceType>(ty);
2432    result = getRValueReferenceType(
2433                 getVariableArrayDecayedType(lv->getPointeeType()));
2434    break;
2435  }
2436
2437  case Type::Atomic: {
2438    const AtomicType *at = cast<AtomicType>(ty);
2439    result = getAtomicType(getVariableArrayDecayedType(at->getValueType()));
2440    break;
2441  }
2442
2443  case Type::ConstantArray: {
2444    const ConstantArrayType *cat = cast<ConstantArrayType>(ty);
2445    result = getConstantArrayType(
2446                 getVariableArrayDecayedType(cat->getElementType()),
2447                                  cat->getSize(),
2448                                  cat->getSizeModifier(),
2449                                  cat->getIndexTypeCVRQualifiers());
2450    break;
2451  }
2452
2453  case Type::DependentSizedArray: {
2454    const DependentSizedArrayType *dat = cast<DependentSizedArrayType>(ty);
2455    result = getDependentSizedArrayType(
2456                 getVariableArrayDecayedType(dat->getElementType()),
2457                                        dat->getSizeExpr(),
2458                                        dat->getSizeModifier(),
2459                                        dat->getIndexTypeCVRQualifiers(),
2460                                        dat->getBracketsRange());
2461    break;
2462  }
2463
2464  // Turn incomplete types into [*] types.
2465  case Type::IncompleteArray: {
2466    const IncompleteArrayType *iat = cast<IncompleteArrayType>(ty);
2467    result = getVariableArrayType(
2468                 getVariableArrayDecayedType(iat->getElementType()),
2469                                  /*size*/ 0,
2470                                  ArrayType::Normal,
2471                                  iat->getIndexTypeCVRQualifiers(),
2472                                  SourceRange());
2473    break;
2474  }
2475
2476  // Turn VLA types into [*] types.
2477  case Type::VariableArray: {
2478    const VariableArrayType *vat = cast<VariableArrayType>(ty);
2479    result = getVariableArrayType(
2480                 getVariableArrayDecayedType(vat->getElementType()),
2481                                  /*size*/ 0,
2482                                  ArrayType::Star,
2483                                  vat->getIndexTypeCVRQualifiers(),
2484                                  vat->getBracketsRange());
2485    break;
2486  }
2487  }
2488
2489  // Apply the top-level qualifiers from the original.
2490  return getQualifiedType(result, split.Quals);
2491}
2492
2493/// getVariableArrayType - Returns a non-unique reference to the type for a
2494/// variable array of the specified element type.
2495QualType ASTContext::getVariableArrayType(QualType EltTy,
2496                                          Expr *NumElts,
2497                                          ArrayType::ArraySizeModifier ASM,
2498                                          unsigned IndexTypeQuals,
2499                                          SourceRange Brackets) const {
2500  // Since we don't unique expressions, it isn't possible to unique VLA's
2501  // that have an expression provided for their size.
2502  QualType Canon;
2503
2504  // Be sure to pull qualifiers off the element type.
2505  if (!EltTy.isCanonical() || EltTy.hasLocalQualifiers()) {
2506    SplitQualType canonSplit = getCanonicalType(EltTy).split();
2507    Canon = getVariableArrayType(QualType(canonSplit.Ty, 0), NumElts, ASM,
2508                                 IndexTypeQuals, Brackets);
2509    Canon = getQualifiedType(Canon, canonSplit.Quals);
2510  }
2511
2512  VariableArrayType *New = new(*this, TypeAlignment)
2513    VariableArrayType(EltTy, Canon, NumElts, ASM, IndexTypeQuals, Brackets);
2514
2515  VariableArrayTypes.push_back(New);
2516  Types.push_back(New);
2517  return QualType(New, 0);
2518}
2519
2520/// getDependentSizedArrayType - Returns a non-unique reference to
2521/// the type for a dependently-sized array of the specified element
2522/// type.
2523QualType ASTContext::getDependentSizedArrayType(QualType elementType,
2524                                                Expr *numElements,
2525                                                ArrayType::ArraySizeModifier ASM,
2526                                                unsigned elementTypeQuals,
2527                                                SourceRange brackets) const {
2528  assert((!numElements || numElements->isTypeDependent() ||
2529          numElements->isValueDependent()) &&
2530         "Size must be type- or value-dependent!");
2531
2532  // Dependently-sized array types that do not have a specified number
2533  // of elements will have their sizes deduced from a dependent
2534  // initializer.  We do no canonicalization here at all, which is okay
2535  // because they can't be used in most locations.
2536  if (!numElements) {
2537    DependentSizedArrayType *newType
2538      = new (*this, TypeAlignment)
2539          DependentSizedArrayType(*this, elementType, QualType(),
2540                                  numElements, ASM, elementTypeQuals,
2541                                  brackets);
2542    Types.push_back(newType);
2543    return QualType(newType, 0);
2544  }
2545
2546  // Otherwise, we actually build a new type every time, but we
2547  // also build a canonical type.
2548
2549  SplitQualType canonElementType = getCanonicalType(elementType).split();
2550
2551  void *insertPos = 0;
2552  llvm::FoldingSetNodeID ID;
2553  DependentSizedArrayType::Profile(ID, *this,
2554                                   QualType(canonElementType.Ty, 0),
2555                                   ASM, elementTypeQuals, numElements);
2556
2557  // Look for an existing type with these properties.
2558  DependentSizedArrayType *canonTy =
2559    DependentSizedArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2560
2561  // If we don't have one, build one.
2562  if (!canonTy) {
2563    canonTy = new (*this, TypeAlignment)
2564      DependentSizedArrayType(*this, QualType(canonElementType.Ty, 0),
2565                              QualType(), numElements, ASM, elementTypeQuals,
2566                              brackets);
2567    DependentSizedArrayTypes.InsertNode(canonTy, insertPos);
2568    Types.push_back(canonTy);
2569  }
2570
2571  // Apply qualifiers from the element type to the array.
2572  QualType canon = getQualifiedType(QualType(canonTy,0),
2573                                    canonElementType.Quals);
2574
2575  // If we didn't need extra canonicalization for the element type,
2576  // then just use that as our result.
2577  if (QualType(canonElementType.Ty, 0) == elementType)
2578    return canon;
2579
2580  // Otherwise, we need to build a type which follows the spelling
2581  // of the element type.
2582  DependentSizedArrayType *sugaredType
2583    = new (*this, TypeAlignment)
2584        DependentSizedArrayType(*this, elementType, canon, numElements,
2585                                ASM, elementTypeQuals, brackets);
2586  Types.push_back(sugaredType);
2587  return QualType(sugaredType, 0);
2588}
2589
2590QualType ASTContext::getIncompleteArrayType(QualType elementType,
2591                                            ArrayType::ArraySizeModifier ASM,
2592                                            unsigned elementTypeQuals) const {
2593  llvm::FoldingSetNodeID ID;
2594  IncompleteArrayType::Profile(ID, elementType, ASM, elementTypeQuals);
2595
2596  void *insertPos = 0;
2597  if (IncompleteArrayType *iat =
2598       IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos))
2599    return QualType(iat, 0);
2600
2601  // If the element type isn't canonical, this won't be a canonical type
2602  // either, so fill in the canonical type field.  We also have to pull
2603  // qualifiers off the element type.
2604  QualType canon;
2605
2606  if (!elementType.isCanonical() || elementType.hasLocalQualifiers()) {
2607    SplitQualType canonSplit = getCanonicalType(elementType).split();
2608    canon = getIncompleteArrayType(QualType(canonSplit.Ty, 0),
2609                                   ASM, elementTypeQuals);
2610    canon = getQualifiedType(canon, canonSplit.Quals);
2611
2612    // Get the new insert position for the node we care about.
2613    IncompleteArrayType *existing =
2614      IncompleteArrayTypes.FindNodeOrInsertPos(ID, insertPos);
2615    assert(!existing && "Shouldn't be in the map!"); (void) existing;
2616  }
2617
2618  IncompleteArrayType *newType = new (*this, TypeAlignment)
2619    IncompleteArrayType(elementType, canon, ASM, elementTypeQuals);
2620
2621  IncompleteArrayTypes.InsertNode(newType, insertPos);
2622  Types.push_back(newType);
2623  return QualType(newType, 0);
2624}
2625
2626/// getVectorType - Return the unique reference to a vector type of
2627/// the specified element type and size. VectorType must be a built-in type.
2628QualType ASTContext::getVectorType(QualType vecType, unsigned NumElts,
2629                                   VectorType::VectorKind VecKind) const {
2630  assert(vecType->isBuiltinType());
2631
2632  // Check if we've already instantiated a vector of this type.
2633  llvm::FoldingSetNodeID ID;
2634  VectorType::Profile(ID, vecType, NumElts, Type::Vector, VecKind);
2635
2636  void *InsertPos = 0;
2637  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2638    return QualType(VTP, 0);
2639
2640  // If the element type isn't canonical, this won't be a canonical type either,
2641  // so fill in the canonical type field.
2642  QualType Canonical;
2643  if (!vecType.isCanonical()) {
2644    Canonical = getVectorType(getCanonicalType(vecType), NumElts, VecKind);
2645
2646    // Get the new insert position for the node we care about.
2647    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2648    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2649  }
2650  VectorType *New = new (*this, TypeAlignment)
2651    VectorType(vecType, NumElts, Canonical, VecKind);
2652  VectorTypes.InsertNode(New, InsertPos);
2653  Types.push_back(New);
2654  return QualType(New, 0);
2655}
2656
2657/// getExtVectorType - Return the unique reference to an extended vector type of
2658/// the specified element type and size. VectorType must be a built-in type.
2659QualType
2660ASTContext::getExtVectorType(QualType vecType, unsigned NumElts) const {
2661  assert(vecType->isBuiltinType() || vecType->isDependentType());
2662
2663  // Check if we've already instantiated a vector of this type.
2664  llvm::FoldingSetNodeID ID;
2665  VectorType::Profile(ID, vecType, NumElts, Type::ExtVector,
2666                      VectorType::GenericVector);
2667  void *InsertPos = 0;
2668  if (VectorType *VTP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos))
2669    return QualType(VTP, 0);
2670
2671  // If the element type isn't canonical, this won't be a canonical type either,
2672  // so fill in the canonical type field.
2673  QualType Canonical;
2674  if (!vecType.isCanonical()) {
2675    Canonical = getExtVectorType(getCanonicalType(vecType), NumElts);
2676
2677    // Get the new insert position for the node we care about.
2678    VectorType *NewIP = VectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2679    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2680  }
2681  ExtVectorType *New = new (*this, TypeAlignment)
2682    ExtVectorType(vecType, NumElts, Canonical);
2683  VectorTypes.InsertNode(New, InsertPos);
2684  Types.push_back(New);
2685  return QualType(New, 0);
2686}
2687
2688QualType
2689ASTContext::getDependentSizedExtVectorType(QualType vecType,
2690                                           Expr *SizeExpr,
2691                                           SourceLocation AttrLoc) const {
2692  llvm::FoldingSetNodeID ID;
2693  DependentSizedExtVectorType::Profile(ID, *this, getCanonicalType(vecType),
2694                                       SizeExpr);
2695
2696  void *InsertPos = 0;
2697  DependentSizedExtVectorType *Canon
2698    = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2699  DependentSizedExtVectorType *New;
2700  if (Canon) {
2701    // We already have a canonical version of this array type; use it as
2702    // the canonical type for a newly-built type.
2703    New = new (*this, TypeAlignment)
2704      DependentSizedExtVectorType(*this, vecType, QualType(Canon, 0),
2705                                  SizeExpr, AttrLoc);
2706  } else {
2707    QualType CanonVecTy = getCanonicalType(vecType);
2708    if (CanonVecTy == vecType) {
2709      New = new (*this, TypeAlignment)
2710        DependentSizedExtVectorType(*this, vecType, QualType(), SizeExpr,
2711                                    AttrLoc);
2712
2713      DependentSizedExtVectorType *CanonCheck
2714        = DependentSizedExtVectorTypes.FindNodeOrInsertPos(ID, InsertPos);
2715      assert(!CanonCheck && "Dependent-sized ext_vector canonical type broken");
2716      (void)CanonCheck;
2717      DependentSizedExtVectorTypes.InsertNode(New, InsertPos);
2718    } else {
2719      QualType Canon = getDependentSizedExtVectorType(CanonVecTy, SizeExpr,
2720                                                      SourceLocation());
2721      New = new (*this, TypeAlignment)
2722        DependentSizedExtVectorType(*this, vecType, Canon, SizeExpr, AttrLoc);
2723    }
2724  }
2725
2726  Types.push_back(New);
2727  return QualType(New, 0);
2728}
2729
2730/// getFunctionNoProtoType - Return a K&R style C function type like 'int()'.
2731///
2732QualType
2733ASTContext::getFunctionNoProtoType(QualType ResultTy,
2734                                   const FunctionType::ExtInfo &Info) const {
2735  const CallingConv DefaultCC = Info.getCC();
2736  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2737                               CC_X86StdCall : DefaultCC;
2738  // Unique functions, to guarantee there is only one function of a particular
2739  // structure.
2740  llvm::FoldingSetNodeID ID;
2741  FunctionNoProtoType::Profile(ID, ResultTy, Info);
2742
2743  void *InsertPos = 0;
2744  if (FunctionNoProtoType *FT =
2745        FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2746    return QualType(FT, 0);
2747
2748  QualType Canonical;
2749  if (!ResultTy.isCanonical() ||
2750      getCanonicalCallConv(CallConv) != CallConv) {
2751    Canonical =
2752      getFunctionNoProtoType(getCanonicalType(ResultTy),
2753                     Info.withCallingConv(getCanonicalCallConv(CallConv)));
2754
2755    // Get the new insert position for the node we care about.
2756    FunctionNoProtoType *NewIP =
2757      FunctionNoProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2758    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2759  }
2760
2761  FunctionProtoType::ExtInfo newInfo = Info.withCallingConv(CallConv);
2762  FunctionNoProtoType *New = new (*this, TypeAlignment)
2763    FunctionNoProtoType(ResultTy, Canonical, newInfo);
2764  Types.push_back(New);
2765  FunctionNoProtoTypes.InsertNode(New, InsertPos);
2766  return QualType(New, 0);
2767}
2768
2769/// \brief Determine whether \p T is canonical as the result type of a function.
2770static bool isCanonicalResultType(QualType T) {
2771  return T.isCanonical() &&
2772         (T.getObjCLifetime() == Qualifiers::OCL_None ||
2773          T.getObjCLifetime() == Qualifiers::OCL_ExplicitNone);
2774}
2775
2776/// getFunctionType - Return a normal function type with a typed argument
2777/// list.  isVariadic indicates whether the argument list includes '...'.
2778QualType
2779ASTContext::getFunctionType(QualType ResultTy, ArrayRef<QualType> ArgArray,
2780                            const FunctionProtoType::ExtProtoInfo &EPI) const {
2781  size_t NumArgs = ArgArray.size();
2782
2783  // Unique functions, to guarantee there is only one function of a particular
2784  // structure.
2785  llvm::FoldingSetNodeID ID;
2786  FunctionProtoType::Profile(ID, ResultTy, ArgArray.begin(), NumArgs, EPI,
2787                             *this);
2788
2789  void *InsertPos = 0;
2790  if (FunctionProtoType *FTP =
2791        FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos))
2792    return QualType(FTP, 0);
2793
2794  // Determine whether the type being created is already canonical or not.
2795  bool isCanonical =
2796    EPI.ExceptionSpecType == EST_None && isCanonicalResultType(ResultTy) &&
2797    !EPI.HasTrailingReturn;
2798  for (unsigned i = 0; i != NumArgs && isCanonical; ++i)
2799    if (!ArgArray[i].isCanonicalAsParam())
2800      isCanonical = false;
2801
2802  const CallingConv DefaultCC = EPI.ExtInfo.getCC();
2803  const CallingConv CallConv = (LangOpts.MRTD && DefaultCC == CC_Default) ?
2804                               CC_X86StdCall : DefaultCC;
2805
2806  // If this type isn't canonical, get the canonical version of it.
2807  // The exception spec is not part of the canonical type.
2808  QualType Canonical;
2809  if (!isCanonical || getCanonicalCallConv(CallConv) != CallConv) {
2810    SmallVector<QualType, 16> CanonicalArgs;
2811    CanonicalArgs.reserve(NumArgs);
2812    for (unsigned i = 0; i != NumArgs; ++i)
2813      CanonicalArgs.push_back(getCanonicalParamType(ArgArray[i]));
2814
2815    FunctionProtoType::ExtProtoInfo CanonicalEPI = EPI;
2816    CanonicalEPI.HasTrailingReturn = false;
2817    CanonicalEPI.ExceptionSpecType = EST_None;
2818    CanonicalEPI.NumExceptions = 0;
2819    CanonicalEPI.ExtInfo
2820      = CanonicalEPI.ExtInfo.withCallingConv(getCanonicalCallConv(CallConv));
2821
2822    // Result types do not have ARC lifetime qualifiers.
2823    QualType CanResultTy = getCanonicalType(ResultTy);
2824    if (ResultTy.getQualifiers().hasObjCLifetime()) {
2825      Qualifiers Qs = CanResultTy.getQualifiers();
2826      Qs.removeObjCLifetime();
2827      CanResultTy = getQualifiedType(CanResultTy.getUnqualifiedType(), Qs);
2828    }
2829
2830    Canonical = getFunctionType(CanResultTy, CanonicalArgs, CanonicalEPI);
2831
2832    // Get the new insert position for the node we care about.
2833    FunctionProtoType *NewIP =
2834      FunctionProtoTypes.FindNodeOrInsertPos(ID, InsertPos);
2835    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
2836  }
2837
2838  // FunctionProtoType objects are allocated with extra bytes after
2839  // them for three variable size arrays at the end:
2840  //  - parameter types
2841  //  - exception types
2842  //  - consumed-arguments flags
2843  // Instead of the exception types, there could be a noexcept
2844  // expression, or information used to resolve the exception
2845  // specification.
2846  size_t Size = sizeof(FunctionProtoType) +
2847                NumArgs * sizeof(QualType);
2848  if (EPI.ExceptionSpecType == EST_Dynamic) {
2849    Size += EPI.NumExceptions * sizeof(QualType);
2850  } else if (EPI.ExceptionSpecType == EST_ComputedNoexcept) {
2851    Size += sizeof(Expr*);
2852  } else if (EPI.ExceptionSpecType == EST_Uninstantiated) {
2853    Size += 2 * sizeof(FunctionDecl*);
2854  } else if (EPI.ExceptionSpecType == EST_Unevaluated) {
2855    Size += sizeof(FunctionDecl*);
2856  }
2857  if (EPI.ConsumedArguments)
2858    Size += NumArgs * sizeof(bool);
2859
2860  FunctionProtoType *FTP = (FunctionProtoType*) Allocate(Size, TypeAlignment);
2861  FunctionProtoType::ExtProtoInfo newEPI = EPI;
2862  newEPI.ExtInfo = EPI.ExtInfo.withCallingConv(CallConv);
2863  new (FTP) FunctionProtoType(ResultTy, ArgArray, Canonical, newEPI);
2864  Types.push_back(FTP);
2865  FunctionProtoTypes.InsertNode(FTP, InsertPos);
2866  return QualType(FTP, 0);
2867}
2868
2869#ifndef NDEBUG
2870static bool NeedsInjectedClassNameType(const RecordDecl *D) {
2871  if (!isa<CXXRecordDecl>(D)) return false;
2872  const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
2873  if (isa<ClassTemplatePartialSpecializationDecl>(RD))
2874    return true;
2875  if (RD->getDescribedClassTemplate() &&
2876      !isa<ClassTemplateSpecializationDecl>(RD))
2877    return true;
2878  return false;
2879}
2880#endif
2881
2882/// getInjectedClassNameType - Return the unique reference to the
2883/// injected class name type for the specified templated declaration.
2884QualType ASTContext::getInjectedClassNameType(CXXRecordDecl *Decl,
2885                                              QualType TST) const {
2886  assert(NeedsInjectedClassNameType(Decl));
2887  if (Decl->TypeForDecl) {
2888    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2889  } else if (CXXRecordDecl *PrevDecl = Decl->getPreviousDecl()) {
2890    assert(PrevDecl->TypeForDecl && "previous declaration has no type");
2891    Decl->TypeForDecl = PrevDecl->TypeForDecl;
2892    assert(isa<InjectedClassNameType>(Decl->TypeForDecl));
2893  } else {
2894    Type *newType =
2895      new (*this, TypeAlignment) InjectedClassNameType(Decl, TST);
2896    Decl->TypeForDecl = newType;
2897    Types.push_back(newType);
2898  }
2899  return QualType(Decl->TypeForDecl, 0);
2900}
2901
2902/// getTypeDeclType - Return the unique reference to the type for the
2903/// specified type declaration.
2904QualType ASTContext::getTypeDeclTypeSlow(const TypeDecl *Decl) const {
2905  assert(Decl && "Passed null for Decl param");
2906  assert(!Decl->TypeForDecl && "TypeForDecl present in slow case");
2907
2908  if (const TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Decl))
2909    return getTypedefType(Typedef);
2910
2911  assert(!isa<TemplateTypeParmDecl>(Decl) &&
2912         "Template type parameter types are always available.");
2913
2914  if (const RecordDecl *Record = dyn_cast<RecordDecl>(Decl)) {
2915    assert(!Record->getPreviousDecl() &&
2916           "struct/union has previous declaration");
2917    assert(!NeedsInjectedClassNameType(Record));
2918    return getRecordType(Record);
2919  } else if (const EnumDecl *Enum = dyn_cast<EnumDecl>(Decl)) {
2920    assert(!Enum->getPreviousDecl() &&
2921           "enum has previous declaration");
2922    return getEnumType(Enum);
2923  } else if (const UnresolvedUsingTypenameDecl *Using =
2924               dyn_cast<UnresolvedUsingTypenameDecl>(Decl)) {
2925    Type *newType = new (*this, TypeAlignment) UnresolvedUsingType(Using);
2926    Decl->TypeForDecl = newType;
2927    Types.push_back(newType);
2928  } else
2929    llvm_unreachable("TypeDecl without a type?");
2930
2931  return QualType(Decl->TypeForDecl, 0);
2932}
2933
2934/// getTypedefType - Return the unique reference to the type for the
2935/// specified typedef name decl.
2936QualType
2937ASTContext::getTypedefType(const TypedefNameDecl *Decl,
2938                           QualType Canonical) const {
2939  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2940
2941  if (Canonical.isNull())
2942    Canonical = getCanonicalType(Decl->getUnderlyingType());
2943  TypedefType *newType = new(*this, TypeAlignment)
2944    TypedefType(Type::Typedef, Decl, Canonical);
2945  Decl->TypeForDecl = newType;
2946  Types.push_back(newType);
2947  return QualType(newType, 0);
2948}
2949
2950QualType ASTContext::getRecordType(const RecordDecl *Decl) const {
2951  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2952
2953  if (const RecordDecl *PrevDecl = Decl->getPreviousDecl())
2954    if (PrevDecl->TypeForDecl)
2955      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2956
2957  RecordType *newType = new (*this, TypeAlignment) RecordType(Decl);
2958  Decl->TypeForDecl = newType;
2959  Types.push_back(newType);
2960  return QualType(newType, 0);
2961}
2962
2963QualType ASTContext::getEnumType(const EnumDecl *Decl) const {
2964  if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);
2965
2966  if (const EnumDecl *PrevDecl = Decl->getPreviousDecl())
2967    if (PrevDecl->TypeForDecl)
2968      return QualType(Decl->TypeForDecl = PrevDecl->TypeForDecl, 0);
2969
2970  EnumType *newType = new (*this, TypeAlignment) EnumType(Decl);
2971  Decl->TypeForDecl = newType;
2972  Types.push_back(newType);
2973  return QualType(newType, 0);
2974}
2975
2976QualType ASTContext::getAttributedType(AttributedType::Kind attrKind,
2977                                       QualType modifiedType,
2978                                       QualType equivalentType) {
2979  llvm::FoldingSetNodeID id;
2980  AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
2981
2982  void *insertPos = 0;
2983  AttributedType *type = AttributedTypes.FindNodeOrInsertPos(id, insertPos);
2984  if (type) return QualType(type, 0);
2985
2986  QualType canon = getCanonicalType(equivalentType);
2987  type = new (*this, TypeAlignment)
2988           AttributedType(canon, attrKind, modifiedType, equivalentType);
2989
2990  Types.push_back(type);
2991  AttributedTypes.InsertNode(type, insertPos);
2992
2993  return QualType(type, 0);
2994}
2995
2996
2997/// \brief Retrieve a substitution-result type.
2998QualType
2999ASTContext::getSubstTemplateTypeParmType(const TemplateTypeParmType *Parm,
3000                                         QualType Replacement) const {
3001  assert(Replacement.isCanonical()
3002         && "replacement types must always be canonical");
3003
3004  llvm::FoldingSetNodeID ID;
3005  SubstTemplateTypeParmType::Profile(ID, Parm, Replacement);
3006  void *InsertPos = 0;
3007  SubstTemplateTypeParmType *SubstParm
3008    = SubstTemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
3009
3010  if (!SubstParm) {
3011    SubstParm = new (*this, TypeAlignment)
3012      SubstTemplateTypeParmType(Parm, Replacement);
3013    Types.push_back(SubstParm);
3014    SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
3015  }
3016
3017  return QualType(SubstParm, 0);
3018}
3019
3020/// \brief Retrieve a
3021QualType ASTContext::getSubstTemplateTypeParmPackType(
3022                                          const TemplateTypeParmType *Parm,
3023                                              const TemplateArgument &ArgPack) {
3024#ifndef NDEBUG
3025  for (TemplateArgument::pack_iterator P = ArgPack.pack_begin(),
3026                                    PEnd = ArgPack.pack_end();
3027       P != PEnd; ++P) {
3028    assert(P->getKind() == TemplateArgument::Type &&"Pack contains a non-type");
3029    assert(P->getAsType().isCanonical() && "Pack contains non-canonical type");
3030  }
3031#endif
3032
3033  llvm::FoldingSetNodeID ID;
3034  SubstTemplateTypeParmPackType::Profile(ID, Parm, ArgPack);
3035  void *InsertPos = 0;
3036  if (SubstTemplateTypeParmPackType *SubstParm
3037        = SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos))
3038    return QualType(SubstParm, 0);
3039
3040  QualType Canon;
3041  if (!Parm->isCanonicalUnqualified()) {
3042    Canon = getCanonicalType(QualType(Parm, 0));
3043    Canon = getSubstTemplateTypeParmPackType(cast<TemplateTypeParmType>(Canon),
3044                                             ArgPack);
3045    SubstTemplateTypeParmPackTypes.FindNodeOrInsertPos(ID, InsertPos);
3046  }
3047
3048  SubstTemplateTypeParmPackType *SubstParm
3049    = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
3050                                                               ArgPack);
3051  Types.push_back(SubstParm);
3052  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
3053  return QualType(SubstParm, 0);
3054}
3055
3056/// \brief Retrieve the template type parameter type for a template
3057/// parameter or parameter pack with the given depth, index, and (optionally)
3058/// name.
3059QualType ASTContext::getTemplateTypeParmType(unsigned Depth, unsigned Index,
3060                                             bool ParameterPack,
3061                                             TemplateTypeParmDecl *TTPDecl) const {
3062  llvm::FoldingSetNodeID ID;
3063  TemplateTypeParmType::Profile(ID, Depth, Index, ParameterPack, TTPDecl);
3064  void *InsertPos = 0;
3065  TemplateTypeParmType *TypeParm
3066    = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
3067
3068  if (TypeParm)
3069    return QualType(TypeParm, 0);
3070
3071  if (TTPDecl) {
3072    QualType Canon = getTemplateTypeParmType(Depth, Index, ParameterPack);
3073    TypeParm = new (*this, TypeAlignment) TemplateTypeParmType(TTPDecl, Canon);
3074
3075    TemplateTypeParmType *TypeCheck
3076      = TemplateTypeParmTypes.FindNodeOrInsertPos(ID, InsertPos);
3077    assert(!TypeCheck && "Template type parameter canonical type broken");
3078    (void)TypeCheck;
3079  } else
3080    TypeParm = new (*this, TypeAlignment)
3081      TemplateTypeParmType(Depth, Index, ParameterPack);
3082
3083  Types.push_back(TypeParm);
3084  TemplateTypeParmTypes.InsertNode(TypeParm, InsertPos);
3085
3086  return QualType(TypeParm, 0);
3087}
3088
3089TypeSourceInfo *
3090ASTContext::getTemplateSpecializationTypeInfo(TemplateName Name,
3091                                              SourceLocation NameLoc,
3092                                        const TemplateArgumentListInfo &Args,
3093                                              QualType Underlying) const {
3094  assert(!Name.getAsDependentTemplateName() &&
3095         "No dependent template names here!");
3096  QualType TST = getTemplateSpecializationType(Name, Args, Underlying);
3097
3098  TypeSourceInfo *DI = CreateTypeSourceInfo(TST);
3099  TemplateSpecializationTypeLoc TL =
3100      DI->getTypeLoc().castAs<TemplateSpecializationTypeLoc>();
3101  TL.setTemplateKeywordLoc(SourceLocation());
3102  TL.setTemplateNameLoc(NameLoc);
3103  TL.setLAngleLoc(Args.getLAngleLoc());
3104  TL.setRAngleLoc(Args.getRAngleLoc());
3105  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
3106    TL.setArgLocInfo(i, Args[i].getLocInfo());
3107  return DI;
3108}
3109
3110QualType
3111ASTContext::getTemplateSpecializationType(TemplateName Template,
3112                                          const TemplateArgumentListInfo &Args,
3113                                          QualType Underlying) const {
3114  assert(!Template.getAsDependentTemplateName() &&
3115         "No dependent template names here!");
3116
3117  unsigned NumArgs = Args.size();
3118
3119  SmallVector<TemplateArgument, 4> ArgVec;
3120  ArgVec.reserve(NumArgs);
3121  for (unsigned i = 0; i != NumArgs; ++i)
3122    ArgVec.push_back(Args[i].getArgument());
3123
3124  return getTemplateSpecializationType(Template, ArgVec.data(), NumArgs,
3125                                       Underlying);
3126}
3127
3128#ifndef NDEBUG
3129static bool hasAnyPackExpansions(const TemplateArgument *Args,
3130                                 unsigned NumArgs) {
3131  for (unsigned I = 0; I != NumArgs; ++I)
3132    if (Args[I].isPackExpansion())
3133      return true;
3134
3135  return true;
3136}
3137#endif
3138
3139QualType
3140ASTContext::getTemplateSpecializationType(TemplateName Template,
3141                                          const TemplateArgument *Args,
3142                                          unsigned NumArgs,
3143                                          QualType Underlying) const {
3144  assert(!Template.getAsDependentTemplateName() &&
3145         "No dependent template names here!");
3146  // Look through qualified template names.
3147  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
3148    Template = TemplateName(QTN->getTemplateDecl());
3149
3150  bool IsTypeAlias =
3151    Template.getAsTemplateDecl() &&
3152    isa<TypeAliasTemplateDecl>(Template.getAsTemplateDecl());
3153  QualType CanonType;
3154  if (!Underlying.isNull())
3155    CanonType = getCanonicalType(Underlying);
3156  else {
3157    // We can get here with an alias template when the specialization contains
3158    // a pack expansion that does not match up with a parameter pack.
3159    assert((!IsTypeAlias || hasAnyPackExpansions(Args, NumArgs)) &&
3160           "Caller must compute aliased type");
3161    IsTypeAlias = false;
3162    CanonType = getCanonicalTemplateSpecializationType(Template, Args,
3163                                                       NumArgs);
3164  }
3165
3166  // Allocate the (non-canonical) template specialization type, but don't
3167  // try to unique it: these types typically have location information that
3168  // we don't unique and don't want to lose.
3169  void *Mem = Allocate(sizeof(TemplateSpecializationType) +
3170                       sizeof(TemplateArgument) * NumArgs +
3171                       (IsTypeAlias? sizeof(QualType) : 0),
3172                       TypeAlignment);
3173  TemplateSpecializationType *Spec
3174    = new (Mem) TemplateSpecializationType(Template, Args, NumArgs, CanonType,
3175                                         IsTypeAlias ? Underlying : QualType());
3176
3177  Types.push_back(Spec);
3178  return QualType(Spec, 0);
3179}
3180
3181QualType
3182ASTContext::getCanonicalTemplateSpecializationType(TemplateName Template,
3183                                                   const TemplateArgument *Args,
3184                                                   unsigned NumArgs) const {
3185  assert(!Template.getAsDependentTemplateName() &&
3186         "No dependent template names here!");
3187
3188  // Look through qualified template names.
3189  if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
3190    Template = TemplateName(QTN->getTemplateDecl());
3191
3192  // Build the canonical template specialization type.
3193  TemplateName CanonTemplate = getCanonicalTemplateName(Template);
3194  SmallVector<TemplateArgument, 4> CanonArgs;
3195  CanonArgs.reserve(NumArgs);
3196  for (unsigned I = 0; I != NumArgs; ++I)
3197    CanonArgs.push_back(getCanonicalTemplateArgument(Args[I]));
3198
3199  // Determine whether this canonical template specialization type already
3200  // exists.
3201  llvm::FoldingSetNodeID ID;
3202  TemplateSpecializationType::Profile(ID, CanonTemplate,
3203                                      CanonArgs.data(), NumArgs, *this);
3204
3205  void *InsertPos = 0;
3206  TemplateSpecializationType *Spec
3207    = TemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3208
3209  if (!Spec) {
3210    // Allocate a new canonical template specialization type.
3211    void *Mem = Allocate((sizeof(TemplateSpecializationType) +
3212                          sizeof(TemplateArgument) * NumArgs),
3213                         TypeAlignment);
3214    Spec = new (Mem) TemplateSpecializationType(CanonTemplate,
3215                                                CanonArgs.data(), NumArgs,
3216                                                QualType(), QualType());
3217    Types.push_back(Spec);
3218    TemplateSpecializationTypes.InsertNode(Spec, InsertPos);
3219  }
3220
3221  assert(Spec->isDependentType() &&
3222         "Non-dependent template-id type must have a canonical type");
3223  return QualType(Spec, 0);
3224}
3225
3226QualType
3227ASTContext::getElaboratedType(ElaboratedTypeKeyword Keyword,
3228                              NestedNameSpecifier *NNS,
3229                              QualType NamedType) const {
3230  llvm::FoldingSetNodeID ID;
3231  ElaboratedType::Profile(ID, Keyword, NNS, NamedType);
3232
3233  void *InsertPos = 0;
3234  ElaboratedType *T = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
3235  if (T)
3236    return QualType(T, 0);
3237
3238  QualType Canon = NamedType;
3239  if (!Canon.isCanonical()) {
3240    Canon = getCanonicalType(NamedType);
3241    ElaboratedType *CheckT = ElaboratedTypes.FindNodeOrInsertPos(ID, InsertPos);
3242    assert(!CheckT && "Elaborated canonical type broken");
3243    (void)CheckT;
3244  }
3245
3246  T = new (*this) ElaboratedType(Keyword, NNS, NamedType, Canon);
3247  Types.push_back(T);
3248  ElaboratedTypes.InsertNode(T, InsertPos);
3249  return QualType(T, 0);
3250}
3251
3252QualType
3253ASTContext::getParenType(QualType InnerType) const {
3254  llvm::FoldingSetNodeID ID;
3255  ParenType::Profile(ID, InnerType);
3256
3257  void *InsertPos = 0;
3258  ParenType *T = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
3259  if (T)
3260    return QualType(T, 0);
3261
3262  QualType Canon = InnerType;
3263  if (!Canon.isCanonical()) {
3264    Canon = getCanonicalType(InnerType);
3265    ParenType *CheckT = ParenTypes.FindNodeOrInsertPos(ID, InsertPos);
3266    assert(!CheckT && "Paren canonical type broken");
3267    (void)CheckT;
3268  }
3269
3270  T = new (*this) ParenType(InnerType, Canon);
3271  Types.push_back(T);
3272  ParenTypes.InsertNode(T, InsertPos);
3273  return QualType(T, 0);
3274}
3275
3276QualType ASTContext::getDependentNameType(ElaboratedTypeKeyword Keyword,
3277                                          NestedNameSpecifier *NNS,
3278                                          const IdentifierInfo *Name,
3279                                          QualType Canon) const {
3280  assert(NNS->isDependent() && "nested-name-specifier must be dependent");
3281
3282  if (Canon.isNull()) {
3283    NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
3284    ElaboratedTypeKeyword CanonKeyword = Keyword;
3285    if (Keyword == ETK_None)
3286      CanonKeyword = ETK_Typename;
3287
3288    if (CanonNNS != NNS || CanonKeyword != Keyword)
3289      Canon = getDependentNameType(CanonKeyword, CanonNNS, Name);
3290  }
3291
3292  llvm::FoldingSetNodeID ID;
3293  DependentNameType::Profile(ID, Keyword, NNS, Name);
3294
3295  void *InsertPos = 0;
3296  DependentNameType *T
3297    = DependentNameTypes.FindNodeOrInsertPos(ID, InsertPos);
3298  if (T)
3299    return QualType(T, 0);
3300
3301  T = new (*this) DependentNameType(Keyword, NNS, Name, Canon);
3302  Types.push_back(T);
3303  DependentNameTypes.InsertNode(T, InsertPos);
3304  return QualType(T, 0);
3305}
3306
3307QualType
3308ASTContext::getDependentTemplateSpecializationType(
3309                                 ElaboratedTypeKeyword Keyword,
3310                                 NestedNameSpecifier *NNS,
3311                                 const IdentifierInfo *Name,
3312                                 const TemplateArgumentListInfo &Args) const {
3313  // TODO: avoid this copy
3314  SmallVector<TemplateArgument, 16> ArgCopy;
3315  for (unsigned I = 0, E = Args.size(); I != E; ++I)
3316    ArgCopy.push_back(Args[I].getArgument());
3317  return getDependentTemplateSpecializationType(Keyword, NNS, Name,
3318                                                ArgCopy.size(),
3319                                                ArgCopy.data());
3320}
3321
3322QualType
3323ASTContext::getDependentTemplateSpecializationType(
3324                                 ElaboratedTypeKeyword Keyword,
3325                                 NestedNameSpecifier *NNS,
3326                                 const IdentifierInfo *Name,
3327                                 unsigned NumArgs,
3328                                 const TemplateArgument *Args) const {
3329  assert((!NNS || NNS->isDependent()) &&
3330         "nested-name-specifier must be dependent");
3331
3332  llvm::FoldingSetNodeID ID;
3333  DependentTemplateSpecializationType::Profile(ID, *this, Keyword, NNS,
3334                                               Name, NumArgs, Args);
3335
3336  void *InsertPos = 0;
3337  DependentTemplateSpecializationType *T
3338    = DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3339  if (T)
3340    return QualType(T, 0);
3341
3342  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
3343
3344  ElaboratedTypeKeyword CanonKeyword = Keyword;
3345  if (Keyword == ETK_None) CanonKeyword = ETK_Typename;
3346
3347  bool AnyNonCanonArgs = false;
3348  SmallVector<TemplateArgument, 16> CanonArgs(NumArgs);
3349  for (unsigned I = 0; I != NumArgs; ++I) {
3350    CanonArgs[I] = getCanonicalTemplateArgument(Args[I]);
3351    if (!CanonArgs[I].structurallyEquals(Args[I]))
3352      AnyNonCanonArgs = true;
3353  }
3354
3355  QualType Canon;
3356  if (AnyNonCanonArgs || CanonNNS != NNS || CanonKeyword != Keyword) {
3357    Canon = getDependentTemplateSpecializationType(CanonKeyword, CanonNNS,
3358                                                   Name, NumArgs,
3359                                                   CanonArgs.data());
3360
3361    // Find the insert position again.
3362    DependentTemplateSpecializationTypes.FindNodeOrInsertPos(ID, InsertPos);
3363  }
3364
3365  void *Mem = Allocate((sizeof(DependentTemplateSpecializationType) +
3366                        sizeof(TemplateArgument) * NumArgs),
3367                       TypeAlignment);
3368  T = new (Mem) DependentTemplateSpecializationType(Keyword, NNS,
3369                                                    Name, NumArgs, Args, Canon);
3370  Types.push_back(T);
3371  DependentTemplateSpecializationTypes.InsertNode(T, InsertPos);
3372  return QualType(T, 0);
3373}
3374
3375QualType ASTContext::getPackExpansionType(QualType Pattern,
3376                                          Optional<unsigned> NumExpansions) {
3377  llvm::FoldingSetNodeID ID;
3378  PackExpansionType::Profile(ID, Pattern, NumExpansions);
3379
3380  assert(Pattern->containsUnexpandedParameterPack() &&
3381         "Pack expansions must expand one or more parameter packs");
3382  void *InsertPos = 0;
3383  PackExpansionType *T
3384    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3385  if (T)
3386    return QualType(T, 0);
3387
3388  QualType Canon;
3389  if (!Pattern.isCanonical()) {
3390    Canon = getCanonicalType(Pattern);
3391    // The canonical type might not contain an unexpanded parameter pack, if it
3392    // contains an alias template specialization which ignores one of its
3393    // parameters.
3394    if (Canon->containsUnexpandedParameterPack()) {
3395      Canon = getPackExpansionType(getCanonicalType(Pattern), NumExpansions);
3396
3397      // Find the insert position again, in case we inserted an element into
3398      // PackExpansionTypes and invalidated our insert position.
3399      PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
3400    }
3401  }
3402
3403  T = new (*this) PackExpansionType(Pattern, Canon, NumExpansions);
3404  Types.push_back(T);
3405  PackExpansionTypes.InsertNode(T, InsertPos);
3406  return QualType(T, 0);
3407}
3408
3409/// CmpProtocolNames - Comparison predicate for sorting protocols
3410/// alphabetically.
3411static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
3412                            const ObjCProtocolDecl *RHS) {
3413  return LHS->getDeclName() < RHS->getDeclName();
3414}
3415
3416static bool areSortedAndUniqued(ObjCProtocolDecl * const *Protocols,
3417                                unsigned NumProtocols) {
3418  if (NumProtocols == 0) return true;
3419
3420  if (Protocols[0]->getCanonicalDecl() != Protocols[0])
3421    return false;
3422
3423  for (unsigned i = 1; i != NumProtocols; ++i)
3424    if (!CmpProtocolNames(Protocols[i-1], Protocols[i]) ||
3425        Protocols[i]->getCanonicalDecl() != Protocols[i])
3426      return false;
3427  return true;
3428}
3429
3430static void SortAndUniqueProtocols(ObjCProtocolDecl **Protocols,
3431                                   unsigned &NumProtocols) {
3432  ObjCProtocolDecl **ProtocolsEnd = Protocols+NumProtocols;
3433
3434  // Sort protocols, keyed by name.
3435  std::sort(Protocols, Protocols+NumProtocols, CmpProtocolNames);
3436
3437  // Canonicalize.
3438  for (unsigned I = 0, N = NumProtocols; I != N; ++I)
3439    Protocols[I] = Protocols[I]->getCanonicalDecl();
3440
3441  // Remove duplicates.
3442  ProtocolsEnd = std::unique(Protocols, ProtocolsEnd);
3443  NumProtocols = ProtocolsEnd-Protocols;
3444}
3445
3446QualType ASTContext::getObjCObjectType(QualType BaseType,
3447                                       ObjCProtocolDecl * const *Protocols,
3448                                       unsigned NumProtocols) const {
3449  // If the base type is an interface and there aren't any protocols
3450  // to add, then the interface type will do just fine.
3451  if (!NumProtocols && isa<ObjCInterfaceType>(BaseType))
3452    return BaseType;
3453
3454  // Look in the folding set for an existing type.
3455  llvm::FoldingSetNodeID ID;
3456  ObjCObjectTypeImpl::Profile(ID, BaseType, Protocols, NumProtocols);
3457  void *InsertPos = 0;
3458  if (ObjCObjectType *QT = ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos))
3459    return QualType(QT, 0);
3460
3461  // Build the canonical type, which has the canonical base type and
3462  // a sorted-and-uniqued list of protocols.
3463  QualType Canonical;
3464  bool ProtocolsSorted = areSortedAndUniqued(Protocols, NumProtocols);
3465  if (!ProtocolsSorted || !BaseType.isCanonical()) {
3466    if (!ProtocolsSorted) {
3467      SmallVector<ObjCProtocolDecl*, 8> Sorted(Protocols,
3468                                                     Protocols + NumProtocols);
3469      unsigned UniqueCount = NumProtocols;
3470
3471      SortAndUniqueProtocols(&Sorted[0], UniqueCount);
3472      Canonical = getObjCObjectType(getCanonicalType(BaseType),
3473                                    &Sorted[0], UniqueCount);
3474    } else {
3475      Canonical = getObjCObjectType(getCanonicalType(BaseType),
3476                                    Protocols, NumProtocols);
3477    }
3478
3479    // Regenerate InsertPos.
3480    ObjCObjectTypes.FindNodeOrInsertPos(ID, InsertPos);
3481  }
3482
3483  unsigned Size = sizeof(ObjCObjectTypeImpl);
3484  Size += NumProtocols * sizeof(ObjCProtocolDecl *);
3485  void *Mem = Allocate(Size, TypeAlignment);
3486  ObjCObjectTypeImpl *T =
3487    new (Mem) ObjCObjectTypeImpl(Canonical, BaseType, Protocols, NumProtocols);
3488
3489  Types.push_back(T);
3490  ObjCObjectTypes.InsertNode(T, InsertPos);
3491  return QualType(T, 0);
3492}
3493
3494/// getObjCObjectPointerType - Return a ObjCObjectPointerType type for
3495/// the given object type.
3496QualType ASTContext::getObjCObjectPointerType(QualType ObjectT) const {
3497  llvm::FoldingSetNodeID ID;
3498  ObjCObjectPointerType::Profile(ID, ObjectT);
3499
3500  void *InsertPos = 0;
3501  if (ObjCObjectPointerType *QT =
3502              ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos))
3503    return QualType(QT, 0);
3504
3505  // Find the canonical object type.
3506  QualType Canonical;
3507  if (!ObjectT.isCanonical()) {
3508    Canonical = getObjCObjectPointerType(getCanonicalType(ObjectT));
3509
3510    // Regenerate InsertPos.
3511    ObjCObjectPointerTypes.FindNodeOrInsertPos(ID, InsertPos);
3512  }
3513
3514  // No match.
3515  void *Mem = Allocate(sizeof(ObjCObjectPointerType), TypeAlignment);
3516  ObjCObjectPointerType *QType =
3517    new (Mem) ObjCObjectPointerType(Canonical, ObjectT);
3518
3519  Types.push_back(QType);
3520  ObjCObjectPointerTypes.InsertNode(QType, InsertPos);
3521  return QualType(QType, 0);
3522}
3523
3524/// getObjCInterfaceType - Return the unique reference to the type for the
3525/// specified ObjC interface decl. The list of protocols is optional.
3526QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
3527                                          ObjCInterfaceDecl *PrevDecl) const {
3528  if (Decl->TypeForDecl)
3529    return QualType(Decl->TypeForDecl, 0);
3530
3531  if (PrevDecl) {
3532    assert(PrevDecl->TypeForDecl && "previous decl has no TypeForDecl");
3533    Decl->TypeForDecl = PrevDecl->TypeForDecl;
3534    return QualType(PrevDecl->TypeForDecl, 0);
3535  }
3536
3537  // Prefer the definition, if there is one.
3538  if (const ObjCInterfaceDecl *Def = Decl->getDefinition())
3539    Decl = Def;
3540
3541  void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
3542  ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
3543  Decl->TypeForDecl = T;
3544  Types.push_back(T);
3545  return QualType(T, 0);
3546}
3547
3548/// getTypeOfExprType - Unlike many "get<Type>" functions, we can't unique
3549/// TypeOfExprType AST's (since expression's are never shared). For example,
3550/// multiple declarations that refer to "typeof(x)" all contain different
3551/// DeclRefExpr's. This doesn't effect the type checker, since it operates
3552/// on canonical type's (which are always unique).
3553QualType ASTContext::getTypeOfExprType(Expr *tofExpr) const {
3554  TypeOfExprType *toe;
3555  if (tofExpr->isTypeDependent()) {
3556    llvm::FoldingSetNodeID ID;
3557    DependentTypeOfExprType::Profile(ID, *this, tofExpr);
3558
3559    void *InsertPos = 0;
3560    DependentTypeOfExprType *Canon
3561      = DependentTypeOfExprTypes.FindNodeOrInsertPos(ID, InsertPos);
3562    if (Canon) {
3563      // We already have a "canonical" version of an identical, dependent
3564      // typeof(expr) type. Use that as our canonical type.
3565      toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr,
3566                                          QualType((TypeOfExprType*)Canon, 0));
3567    } else {
3568      // Build a new, canonical typeof(expr) type.
3569      Canon
3570        = new (*this, TypeAlignment) DependentTypeOfExprType(*this, tofExpr);
3571      DependentTypeOfExprTypes.InsertNode(Canon, InsertPos);
3572      toe = Canon;
3573    }
3574  } else {
3575    QualType Canonical = getCanonicalType(tofExpr->getType());
3576    toe = new (*this, TypeAlignment) TypeOfExprType(tofExpr, Canonical);
3577  }
3578  Types.push_back(toe);
3579  return QualType(toe, 0);
3580}
3581
3582/// getTypeOfType -  Unlike many "get<Type>" functions, we don't unique
3583/// TypeOfType AST's. The only motivation to unique these nodes would be
3584/// memory savings. Since typeof(t) is fairly uncommon, space shouldn't be
3585/// an issue. This doesn't effect the type checker, since it operates
3586/// on canonical type's (which are always unique).
3587QualType ASTContext::getTypeOfType(QualType tofType) const {
3588  QualType Canonical = getCanonicalType(tofType);
3589  TypeOfType *tot = new (*this, TypeAlignment) TypeOfType(tofType, Canonical);
3590  Types.push_back(tot);
3591  return QualType(tot, 0);
3592}
3593
3594
3595/// getDecltypeType -  Unlike many "get<Type>" functions, we don't unique
3596/// DecltypeType AST's. The only motivation to unique these nodes would be
3597/// memory savings. Since decltype(t) is fairly uncommon, space shouldn't be
3598/// an issue. This doesn't effect the type checker, since it operates
3599/// on canonical types (which are always unique).
3600QualType ASTContext::getDecltypeType(Expr *e, QualType UnderlyingType) const {
3601  DecltypeType *dt;
3602
3603  // C++0x [temp.type]p2:
3604  //   If an expression e involves a template parameter, decltype(e) denotes a
3605  //   unique dependent type. Two such decltype-specifiers refer to the same
3606  //   type only if their expressions are equivalent (14.5.6.1).
3607  if (e->isInstantiationDependent()) {
3608    llvm::FoldingSetNodeID ID;
3609    DependentDecltypeType::Profile(ID, *this, e);
3610
3611    void *InsertPos = 0;
3612    DependentDecltypeType *Canon
3613      = DependentDecltypeTypes.FindNodeOrInsertPos(ID, InsertPos);
3614    if (Canon) {
3615      // We already have a "canonical" version of an equivalent, dependent
3616      // decltype type. Use that as our canonical type.
3617      dt = new (*this, TypeAlignment) DecltypeType(e, UnderlyingType,
3618                                       QualType((DecltypeType*)Canon, 0));
3619    } else {
3620      // Build a new, canonical typeof(expr) type.
3621      Canon = new (*this, TypeAlignment) DependentDecltypeType(*this, e);
3622      DependentDecltypeTypes.InsertNode(Canon, InsertPos);
3623      dt = Canon;
3624    }
3625  } else {
3626    dt = new (*this, TypeAlignment) DecltypeType(e, UnderlyingType,
3627                                      getCanonicalType(UnderlyingType));
3628  }
3629  Types.push_back(dt);
3630  return QualType(dt, 0);
3631}
3632
3633/// getUnaryTransformationType - We don't unique these, since the memory
3634/// savings are minimal and these are rare.
3635QualType ASTContext::getUnaryTransformType(QualType BaseType,
3636                                           QualType UnderlyingType,
3637                                           UnaryTransformType::UTTKind Kind)
3638    const {
3639  UnaryTransformType *Ty =
3640    new (*this, TypeAlignment) UnaryTransformType (BaseType, UnderlyingType,
3641                                                   Kind,
3642                                 UnderlyingType->isDependentType() ?
3643                                 QualType() : getCanonicalType(UnderlyingType));
3644  Types.push_back(Ty);
3645  return QualType(Ty, 0);
3646}
3647
3648/// getAutoType - Return the uniqued reference to the 'auto' type which has been
3649/// deduced to the given type, or to the canonical undeduced 'auto' type, or the
3650/// canonical deduced-but-dependent 'auto' type.
3651QualType ASTContext::getAutoType(QualType DeducedType, bool IsDecltypeAuto,
3652                             bool IsDependent, bool IsParameterPack) const {
3653  if (DeducedType.isNull() && !IsDecltypeAuto && !IsDependent &&
3654                              !IsParameterPack)
3655    return getAutoDeductType();
3656  assert(!IsParameterPack || DeducedType.isNull()
3657           && "Auto parameter pack: auto ... a should always be undeduced!");
3658  // Look in the folding set for an existing type.
3659  void *InsertPos = 0;
3660  llvm::FoldingSetNodeID ID;
3661  AutoType::Profile(ID, DeducedType, IsDecltypeAuto, IsDependent,
3662     IsParameterPack);
3663  if (AutoType *AT = AutoTypes.FindNodeOrInsertPos(ID, InsertPos))
3664    return QualType(AT, 0);
3665
3666  AutoType *AT = new (*this, TypeAlignment) AutoType(DeducedType,
3667                                                     IsDecltypeAuto,
3668                                                     IsDependent,
3669                                                     IsParameterPack);
3670  Types.push_back(AT);
3671  if (InsertPos)
3672    AutoTypes.InsertNode(AT, InsertPos);
3673  return QualType(AT, 0);
3674}
3675
3676/// getAtomicType - Return the uniqued reference to the atomic type for
3677/// the given value type.
3678QualType ASTContext::getAtomicType(QualType T) const {
3679  // Unique pointers, to guarantee there is only one pointer of a particular
3680  // structure.
3681  llvm::FoldingSetNodeID ID;
3682  AtomicType::Profile(ID, T);
3683
3684  void *InsertPos = 0;
3685  if (AtomicType *AT = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos))
3686    return QualType(AT, 0);
3687
3688  // If the atomic value type isn't canonical, this won't be a canonical type
3689  // either, so fill in the canonical type field.
3690  QualType Canonical;
3691  if (!T.isCanonical()) {
3692    Canonical = getAtomicType(getCanonicalType(T));
3693
3694    // Get the new insert position for the node we care about.
3695    AtomicType *NewIP = AtomicTypes.FindNodeOrInsertPos(ID, InsertPos);
3696    assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
3697  }
3698  AtomicType *New = new (*this, TypeAlignment) AtomicType(T, Canonical);
3699  Types.push_back(New);
3700  AtomicTypes.InsertNode(New, InsertPos);
3701  return QualType(New, 0);
3702}
3703
3704/// getAutoDeductType - Get type pattern for deducing against 'auto'.
3705QualType ASTContext::getAutoDeductType() const {
3706  if (AutoDeductTy.isNull())
3707    AutoDeductTy = QualType(
3708      new (*this, TypeAlignment) AutoType(QualType(), /*decltype(auto)*/false,
3709                                          /*dependent*/false,
3710                                          /*IsParameterPack*/false),
3711      0);
3712  return AutoDeductTy;
3713}
3714
3715/// getAutoRRefDeductType - Get type pattern for deducing against 'auto &&'.
3716QualType ASTContext::getAutoRRefDeductType() const {
3717  if (AutoRRefDeductTy.isNull())
3718    AutoRRefDeductTy = getRValueReferenceType(getAutoDeductType());
3719  assert(!AutoRRefDeductTy.isNull() && "can't build 'auto &&' pattern");
3720  return AutoRRefDeductTy;
3721}
3722
3723/// getTagDeclType - Return the unique reference to the type for the
3724/// specified TagDecl (struct/union/class/enum) decl.
3725QualType ASTContext::getTagDeclType(const TagDecl *Decl) const {
3726  assert (Decl);
3727  // FIXME: What is the design on getTagDeclType when it requires casting
3728  // away const?  mutable?
3729  return getTypeDeclType(const_cast<TagDecl*>(Decl));
3730}
3731
3732/// getSizeType - Return the unique type for "size_t" (C99 7.17), the result
3733/// of the sizeof operator (C99 6.5.3.4p4). The value is target dependent and
3734/// needs to agree with the definition in <stddef.h>.
3735CanQualType ASTContext::getSizeType() const {
3736  return getFromTargetType(Target->getSizeType());
3737}
3738
3739/// getIntMaxType - Return the unique type for "intmax_t" (C99 7.18.1.5).
3740CanQualType ASTContext::getIntMaxType() const {
3741  return getFromTargetType(Target->getIntMaxType());
3742}
3743
3744/// getUIntMaxType - Return the unique type for "uintmax_t" (C99 7.18.1.5).
3745CanQualType ASTContext::getUIntMaxType() const {
3746  return getFromTargetType(Target->getUIntMaxType());
3747}
3748
3749/// getSignedWCharType - Return the type of "signed wchar_t".
3750/// Used when in C++, as a GCC extension.
3751QualType ASTContext::getSignedWCharType() const {
3752  // FIXME: derive from "Target" ?
3753  return WCharTy;
3754}
3755
3756/// getUnsignedWCharType - Return the type of "unsigned wchar_t".
3757/// Used when in C++, as a GCC extension.
3758QualType ASTContext::getUnsignedWCharType() const {
3759  // FIXME: derive from "Target" ?
3760  return UnsignedIntTy;
3761}
3762
3763QualType ASTContext::getIntPtrType() const {
3764  return getFromTargetType(Target->getIntPtrType());
3765}
3766
3767QualType ASTContext::getUIntPtrType() const {
3768  return getCorrespondingUnsignedType(getIntPtrType());
3769}
3770
3771/// getPointerDiffType - Return the unique type for "ptrdiff_t" (C99 7.17)
3772/// defined in <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
3773QualType ASTContext::getPointerDiffType() const {
3774  return getFromTargetType(Target->getPtrDiffType(0));
3775}
3776
3777/// \brief Return the unique type for "pid_t" defined in
3778/// <sys/types.h>. We need this to compute the correct type for vfork().
3779QualType ASTContext::getProcessIDType() const {
3780  return getFromTargetType(Target->getProcessIDType());
3781}
3782
3783//===----------------------------------------------------------------------===//
3784//                              Type Operators
3785//===----------------------------------------------------------------------===//
3786
3787CanQualType ASTContext::getCanonicalParamType(QualType T) const {
3788  // Push qualifiers into arrays, and then discard any remaining
3789  // qualifiers.
3790  T = getCanonicalType(T);
3791  T = getVariableArrayDecayedType(T);
3792  const Type *Ty = T.getTypePtr();
3793  QualType Result;
3794  if (isa<ArrayType>(Ty)) {
3795    Result = getArrayDecayedType(QualType(Ty,0));
3796  } else if (isa<FunctionType>(Ty)) {
3797    Result = getPointerType(QualType(Ty, 0));
3798  } else {
3799    Result = QualType(Ty, 0);
3800  }
3801
3802  return CanQualType::CreateUnsafe(Result);
3803}
3804
3805QualType ASTContext::getUnqualifiedArrayType(QualType type,
3806                                             Qualifiers &quals) {
3807  SplitQualType splitType = type.getSplitUnqualifiedType();
3808
3809  // FIXME: getSplitUnqualifiedType() actually walks all the way to
3810  // the unqualified desugared type and then drops it on the floor.
3811  // We then have to strip that sugar back off with
3812  // getUnqualifiedDesugaredType(), which is silly.
3813  const ArrayType *AT =
3814    dyn_cast<ArrayType>(splitType.Ty->getUnqualifiedDesugaredType());
3815
3816  // If we don't have an array, just use the results in splitType.
3817  if (!AT) {
3818    quals = splitType.Quals;
3819    return QualType(splitType.Ty, 0);
3820  }
3821
3822  // Otherwise, recurse on the array's element type.
3823  QualType elementType = AT->getElementType();
3824  QualType unqualElementType = getUnqualifiedArrayType(elementType, quals);
3825
3826  // If that didn't change the element type, AT has no qualifiers, so we
3827  // can just use the results in splitType.
3828  if (elementType == unqualElementType) {
3829    assert(quals.empty()); // from the recursive call
3830    quals = splitType.Quals;
3831    return QualType(splitType.Ty, 0);
3832  }
3833
3834  // Otherwise, add in the qualifiers from the outermost type, then
3835  // build the type back up.
3836  quals.addConsistentQualifiers(splitType.Quals);
3837
3838  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
3839    return getConstantArrayType(unqualElementType, CAT->getSize(),
3840                                CAT->getSizeModifier(), 0);
3841  }
3842
3843  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
3844    return getIncompleteArrayType(unqualElementType, IAT->getSizeModifier(), 0);
3845  }
3846
3847  if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT)) {
3848    return getVariableArrayType(unqualElementType,
3849                                VAT->getSizeExpr(),
3850                                VAT->getSizeModifier(),
3851                                VAT->getIndexTypeCVRQualifiers(),
3852                                VAT->getBracketsRange());
3853  }
3854
3855  const DependentSizedArrayType *DSAT = cast<DependentSizedArrayType>(AT);
3856  return getDependentSizedArrayType(unqualElementType, DSAT->getSizeExpr(),
3857                                    DSAT->getSizeModifier(), 0,
3858                                    SourceRange());
3859}
3860
3861/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types  that
3862/// may be similar (C++ 4.4), replaces T1 and T2 with the type that
3863/// they point to and return true. If T1 and T2 aren't pointer types
3864/// or pointer-to-member types, or if they are not similar at this
3865/// level, returns false and leaves T1 and T2 unchanged. Top-level
3866/// qualifiers on T1 and T2 are ignored. This function will typically
3867/// be called in a loop that successively "unwraps" pointer and
3868/// pointer-to-member types to compare them at each level.
3869bool ASTContext::UnwrapSimilarPointerTypes(QualType &T1, QualType &T2) {
3870  const PointerType *T1PtrType = T1->getAs<PointerType>(),
3871                    *T2PtrType = T2->getAs<PointerType>();
3872  if (T1PtrType && T2PtrType) {
3873    T1 = T1PtrType->getPointeeType();
3874    T2 = T2PtrType->getPointeeType();
3875    return true;
3876  }
3877
3878  const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
3879                          *T2MPType = T2->getAs<MemberPointerType>();
3880  if (T1MPType && T2MPType &&
3881      hasSameUnqualifiedType(QualType(T1MPType->getClass(), 0),
3882                             QualType(T2MPType->getClass(), 0))) {
3883    T1 = T1MPType->getPointeeType();
3884    T2 = T2MPType->getPointeeType();
3885    return true;
3886  }
3887
3888  if (getLangOpts().ObjC1) {
3889    const ObjCObjectPointerType *T1OPType = T1->getAs<ObjCObjectPointerType>(),
3890                                *T2OPType = T2->getAs<ObjCObjectPointerType>();
3891    if (T1OPType && T2OPType) {
3892      T1 = T1OPType->getPointeeType();
3893      T2 = T2OPType->getPointeeType();
3894      return true;
3895    }
3896  }
3897
3898  // FIXME: Block pointers, too?
3899
3900  return false;
3901}
3902
3903DeclarationNameInfo
3904ASTContext::getNameForTemplate(TemplateName Name,
3905                               SourceLocation NameLoc) const {
3906  switch (Name.getKind()) {
3907  case TemplateName::QualifiedTemplate:
3908  case TemplateName::Template:
3909    // DNInfo work in progress: CHECKME: what about DNLoc?
3910    return DeclarationNameInfo(Name.getAsTemplateDecl()->getDeclName(),
3911                               NameLoc);
3912
3913  case TemplateName::OverloadedTemplate: {
3914    OverloadedTemplateStorage *Storage = Name.getAsOverloadedTemplate();
3915    // DNInfo work in progress: CHECKME: what about DNLoc?
3916    return DeclarationNameInfo((*Storage->begin())->getDeclName(), NameLoc);
3917  }
3918
3919  case TemplateName::DependentTemplate: {
3920    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3921    DeclarationName DName;
3922    if (DTN->isIdentifier()) {
3923      DName = DeclarationNames.getIdentifier(DTN->getIdentifier());
3924      return DeclarationNameInfo(DName, NameLoc);
3925    } else {
3926      DName = DeclarationNames.getCXXOperatorName(DTN->getOperator());
3927      // DNInfo work in progress: FIXME: source locations?
3928      DeclarationNameLoc DNLoc;
3929      DNLoc.CXXOperatorName.BeginOpNameLoc = SourceLocation().getRawEncoding();
3930      DNLoc.CXXOperatorName.EndOpNameLoc = SourceLocation().getRawEncoding();
3931      return DeclarationNameInfo(DName, NameLoc, DNLoc);
3932    }
3933  }
3934
3935  case TemplateName::SubstTemplateTemplateParm: {
3936    SubstTemplateTemplateParmStorage *subst
3937      = Name.getAsSubstTemplateTemplateParm();
3938    return DeclarationNameInfo(subst->getParameter()->getDeclName(),
3939                               NameLoc);
3940  }
3941
3942  case TemplateName::SubstTemplateTemplateParmPack: {
3943    SubstTemplateTemplateParmPackStorage *subst
3944      = Name.getAsSubstTemplateTemplateParmPack();
3945    return DeclarationNameInfo(subst->getParameterPack()->getDeclName(),
3946                               NameLoc);
3947  }
3948  }
3949
3950  llvm_unreachable("bad template name kind!");
3951}
3952
3953TemplateName ASTContext::getCanonicalTemplateName(TemplateName Name) const {
3954  switch (Name.getKind()) {
3955  case TemplateName::QualifiedTemplate:
3956  case TemplateName::Template: {
3957    TemplateDecl *Template = Name.getAsTemplateDecl();
3958    if (TemplateTemplateParmDecl *TTP
3959          = dyn_cast<TemplateTemplateParmDecl>(Template))
3960      Template = getCanonicalTemplateTemplateParmDecl(TTP);
3961
3962    // The canonical template name is the canonical template declaration.
3963    return TemplateName(cast<TemplateDecl>(Template->getCanonicalDecl()));
3964  }
3965
3966  case TemplateName::OverloadedTemplate:
3967    llvm_unreachable("cannot canonicalize overloaded template");
3968
3969  case TemplateName::DependentTemplate: {
3970    DependentTemplateName *DTN = Name.getAsDependentTemplateName();
3971    assert(DTN && "Non-dependent template names must refer to template decls.");
3972    return DTN->CanonicalTemplateName;
3973  }
3974
3975  case TemplateName::SubstTemplateTemplateParm: {
3976    SubstTemplateTemplateParmStorage *subst
3977      = Name.getAsSubstTemplateTemplateParm();
3978    return getCanonicalTemplateName(subst->getReplacement());
3979  }
3980
3981  case TemplateName::SubstTemplateTemplateParmPack: {
3982    SubstTemplateTemplateParmPackStorage *subst
3983                                  = Name.getAsSubstTemplateTemplateParmPack();
3984    TemplateTemplateParmDecl *canonParameter
3985      = getCanonicalTemplateTemplateParmDecl(subst->getParameterPack());
3986    TemplateArgument canonArgPack
3987      = getCanonicalTemplateArgument(subst->getArgumentPack());
3988    return getSubstTemplateTemplateParmPack(canonParameter, canonArgPack);
3989  }
3990  }
3991
3992  llvm_unreachable("bad template name!");
3993}
3994
3995bool ASTContext::hasSameTemplateName(TemplateName X, TemplateName Y) {
3996  X = getCanonicalTemplateName(X);
3997  Y = getCanonicalTemplateName(Y);
3998  return X.getAsVoidPointer() == Y.getAsVoidPointer();
3999}
4000
4001TemplateArgument
4002ASTContext::getCanonicalTemplateArgument(const TemplateArgument &Arg) const {
4003  switch (Arg.getKind()) {
4004    case TemplateArgument::Null:
4005      return Arg;
4006
4007    case TemplateArgument::Expression:
4008      return Arg;
4009
4010    case TemplateArgument::Declaration: {
4011      ValueDecl *D = cast<ValueDecl>(Arg.getAsDecl()->getCanonicalDecl());
4012      return TemplateArgument(D, Arg.isDeclForReferenceParam());
4013    }
4014
4015    case TemplateArgument::NullPtr:
4016      return TemplateArgument(getCanonicalType(Arg.getNullPtrType()),
4017                              /*isNullPtr*/true);
4018
4019    case TemplateArgument::Template:
4020      return TemplateArgument(getCanonicalTemplateName(Arg.getAsTemplate()));
4021
4022    case TemplateArgument::TemplateExpansion:
4023      return TemplateArgument(getCanonicalTemplateName(
4024                                         Arg.getAsTemplateOrTemplatePattern()),
4025                              Arg.getNumTemplateExpansions());
4026
4027    case TemplateArgument::Integral:
4028      return TemplateArgument(Arg, getCanonicalType(Arg.getIntegralType()));
4029
4030    case TemplateArgument::Type:
4031      return TemplateArgument(getCanonicalType(Arg.getAsType()));
4032
4033    case TemplateArgument::Pack: {
4034      if (Arg.pack_size() == 0)
4035        return Arg;
4036
4037      TemplateArgument *CanonArgs
4038        = new (*this) TemplateArgument[Arg.pack_size()];
4039      unsigned Idx = 0;
4040      for (TemplateArgument::pack_iterator A = Arg.pack_begin(),
4041                                        AEnd = Arg.pack_end();
4042           A != AEnd; (void)++A, ++Idx)
4043        CanonArgs[Idx] = getCanonicalTemplateArgument(*A);
4044
4045      return TemplateArgument(CanonArgs, Arg.pack_size());
4046    }
4047  }
4048
4049  // Silence GCC warning
4050  llvm_unreachable("Unhandled template argument kind");
4051}
4052
4053NestedNameSpecifier *
4054ASTContext::getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const {
4055  if (!NNS)
4056    return 0;
4057
4058  switch (NNS->getKind()) {
4059  case NestedNameSpecifier::Identifier:
4060    // Canonicalize the prefix but keep the identifier the same.
4061    return NestedNameSpecifier::Create(*this,
4062                         getCanonicalNestedNameSpecifier(NNS->getPrefix()),
4063                                       NNS->getAsIdentifier());
4064
4065  case NestedNameSpecifier::Namespace:
4066    // A namespace is canonical; build a nested-name-specifier with
4067    // this namespace and no prefix.
4068    return NestedNameSpecifier::Create(*this, 0,
4069                                 NNS->getAsNamespace()->getOriginalNamespace());
4070
4071  case NestedNameSpecifier::NamespaceAlias:
4072    // A namespace is canonical; build a nested-name-specifier with
4073    // this namespace and no prefix.
4074    return NestedNameSpecifier::Create(*this, 0,
4075                                    NNS->getAsNamespaceAlias()->getNamespace()
4076                                                      ->getOriginalNamespace());
4077
4078  case NestedNameSpecifier::TypeSpec:
4079  case NestedNameSpecifier::TypeSpecWithTemplate: {
4080    QualType T = getCanonicalType(QualType(NNS->getAsType(), 0));
4081
4082    // If we have some kind of dependent-named type (e.g., "typename T::type"),
4083    // break it apart into its prefix and identifier, then reconsititute those
4084    // as the canonical nested-name-specifier. This is required to canonicalize
4085    // a dependent nested-name-specifier involving typedefs of dependent-name
4086    // types, e.g.,
4087    //   typedef typename T::type T1;
4088    //   typedef typename T1::type T2;
4089    if (const DependentNameType *DNT = T->getAs<DependentNameType>())
4090      return NestedNameSpecifier::Create(*this, DNT->getQualifier(),
4091                           const_cast<IdentifierInfo *>(DNT->getIdentifier()));
4092
4093    // Otherwise, just canonicalize the type, and force it to be a TypeSpec.
4094    // FIXME: Why are TypeSpec and TypeSpecWithTemplate distinct in the
4095    // first place?
4096    return NestedNameSpecifier::Create(*this, 0, false,
4097                                       const_cast<Type*>(T.getTypePtr()));
4098  }
4099
4100  case NestedNameSpecifier::Global:
4101    // The global specifier is canonical and unique.
4102    return NNS;
4103  }
4104
4105  llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
4106}
4107
4108
4109const ArrayType *ASTContext::getAsArrayType(QualType T) const {
4110  // Handle the non-qualified case efficiently.
4111  if (!T.hasLocalQualifiers()) {
4112    // Handle the common positive case fast.
4113    if (const ArrayType *AT = dyn_cast<ArrayType>(T))
4114      return AT;
4115  }
4116
4117  // Handle the common negative case fast.
4118  if (!isa<ArrayType>(T.getCanonicalType()))
4119    return 0;
4120
4121  // Apply any qualifiers from the array type to the element type.  This
4122  // implements C99 6.7.3p8: "If the specification of an array type includes
4123  // any type qualifiers, the element type is so qualified, not the array type."
4124
4125  // If we get here, we either have type qualifiers on the type, or we have
4126  // sugar such as a typedef in the way.  If we have type qualifiers on the type
4127  // we must propagate them down into the element type.
4128
4129  SplitQualType split = T.getSplitDesugaredType();
4130  Qualifiers qs = split.Quals;
4131
4132  // If we have a simple case, just return now.
4133  const ArrayType *ATy = dyn_cast<ArrayType>(split.Ty);
4134  if (ATy == 0 || qs.empty())
4135    return ATy;
4136
4137  // Otherwise, we have an array and we have qualifiers on it.  Push the
4138  // qualifiers into the array element type and return a new array type.
4139  QualType NewEltTy = getQualifiedType(ATy->getElementType(), qs);
4140
4141  if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(ATy))
4142    return cast<ArrayType>(getConstantArrayType(NewEltTy, CAT->getSize(),
4143                                                CAT->getSizeModifier(),
4144                                           CAT->getIndexTypeCVRQualifiers()));
4145  if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(ATy))
4146    return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
4147                                                  IAT->getSizeModifier(),
4148                                           IAT->getIndexTypeCVRQualifiers()));
4149
4150  if (const DependentSizedArrayType *DSAT
4151        = dyn_cast<DependentSizedArrayType>(ATy))
4152    return cast<ArrayType>(
4153                     getDependentSizedArrayType(NewEltTy,
4154                                                DSAT->getSizeExpr(),
4155                                                DSAT->getSizeModifier(),
4156                                              DSAT->getIndexTypeCVRQualifiers(),
4157                                                DSAT->getBracketsRange()));
4158
4159  const VariableArrayType *VAT = cast<VariableArrayType>(ATy);
4160  return cast<ArrayType>(getVariableArrayType(NewEltTy,
4161                                              VAT->getSizeExpr(),
4162                                              VAT->getSizeModifier(),
4163                                              VAT->getIndexTypeCVRQualifiers(),
4164                                              VAT->getBracketsRange()));
4165}
4166
4167QualType ASTContext::getAdjustedParameterType(QualType T) const {
4168  if (T->isArrayType() || T->isFunctionType())
4169    return getDecayedType(T);
4170  return T;
4171}
4172
4173QualType ASTContext::getSignatureParameterType(QualType T) const {
4174  T = getVariableArrayDecayedType(T);
4175  T = getAdjustedParameterType(T);
4176  return T.getUnqualifiedType();
4177}
4178
4179/// getArrayDecayedType - Return the properly qualified result of decaying the
4180/// specified array type to a pointer.  This operation is non-trivial when
4181/// handling typedefs etc.  The canonical type of "T" must be an array type,
4182/// this returns a pointer to a properly qualified element of the array.
4183///
4184/// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
4185QualType ASTContext::getArrayDecayedType(QualType Ty) const {
4186  // Get the element type with 'getAsArrayType' so that we don't lose any
4187  // typedefs in the element type of the array.  This also handles propagation
4188  // of type qualifiers from the array type into the element type if present
4189  // (C99 6.7.3p8).
4190  const ArrayType *PrettyArrayType = getAsArrayType(Ty);
4191  assert(PrettyArrayType && "Not an array type!");
4192
4193  QualType PtrTy = getPointerType(PrettyArrayType->getElementType());
4194
4195  // int x[restrict 4] ->  int *restrict
4196  return getQualifiedType(PtrTy, PrettyArrayType->getIndexTypeQualifiers());
4197}
4198
4199QualType ASTContext::getBaseElementType(const ArrayType *array) const {
4200  return getBaseElementType(array->getElementType());
4201}
4202
4203QualType ASTContext::getBaseElementType(QualType type) const {
4204  Qualifiers qs;
4205  while (true) {
4206    SplitQualType split = type.getSplitDesugaredType();
4207    const ArrayType *array = split.Ty->getAsArrayTypeUnsafe();
4208    if (!array) break;
4209
4210    type = array->getElementType();
4211    qs.addConsistentQualifiers(split.Quals);
4212  }
4213
4214  return getQualifiedType(type, qs);
4215}
4216
4217/// getConstantArrayElementCount - Returns number of constant array elements.
4218uint64_t
4219ASTContext::getConstantArrayElementCount(const ConstantArrayType *CA)  const {
4220  uint64_t ElementCount = 1;
4221  do {
4222    ElementCount *= CA->getSize().getZExtValue();
4223    CA = dyn_cast_or_null<ConstantArrayType>(
4224      CA->getElementType()->getAsArrayTypeUnsafe());
4225  } while (CA);
4226  return ElementCount;
4227}
4228
4229/// getFloatingRank - Return a relative rank for floating point types.
4230/// This routine will assert if passed a built-in type that isn't a float.
4231static FloatingRank getFloatingRank(QualType T) {
4232  if (const ComplexType *CT = T->getAs<ComplexType>())
4233    return getFloatingRank(CT->getElementType());
4234
4235  assert(T->getAs<BuiltinType>() && "getFloatingRank(): not a floating type");
4236  switch (T->getAs<BuiltinType>()->getKind()) {
4237  default: llvm_unreachable("getFloatingRank(): not a floating type");
4238  case BuiltinType::Half:       return HalfRank;
4239  case BuiltinType::Float:      return FloatRank;
4240  case BuiltinType::Double:     return DoubleRank;
4241  case BuiltinType::LongDouble: return LongDoubleRank;
4242  }
4243}
4244
4245/// getFloatingTypeOfSizeWithinDomain - Returns a real floating
4246/// point or a complex type (based on typeDomain/typeSize).
4247/// 'typeDomain' is a real floating point or complex type.
4248/// 'typeSize' is a real floating point or complex type.
4249QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
4250                                                       QualType Domain) const {
4251  FloatingRank EltRank = getFloatingRank(Size);
4252  if (Domain->isComplexType()) {
4253    switch (EltRank) {
4254    case HalfRank: llvm_unreachable("Complex half is not supported");
4255    case FloatRank:      return FloatComplexTy;
4256    case DoubleRank:     return DoubleComplexTy;
4257    case LongDoubleRank: return LongDoubleComplexTy;
4258    }
4259  }
4260
4261  assert(Domain->isRealFloatingType() && "Unknown domain!");
4262  switch (EltRank) {
4263  case HalfRank:       return HalfTy;
4264  case FloatRank:      return FloatTy;
4265  case DoubleRank:     return DoubleTy;
4266  case LongDoubleRank: return LongDoubleTy;
4267  }
4268  llvm_unreachable("getFloatingRank(): illegal value for rank");
4269}
4270
4271/// getFloatingTypeOrder - Compare the rank of the two specified floating
4272/// point types, ignoring the domain of the type (i.e. 'double' ==
4273/// '_Complex double').  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
4274/// LHS < RHS, return -1.
4275int ASTContext::getFloatingTypeOrder(QualType LHS, QualType RHS) const {
4276  FloatingRank LHSR = getFloatingRank(LHS);
4277  FloatingRank RHSR = getFloatingRank(RHS);
4278
4279  if (LHSR == RHSR)
4280    return 0;
4281  if (LHSR > RHSR)
4282    return 1;
4283  return -1;
4284}
4285
4286/// getIntegerRank - Return an integer conversion rank (C99 6.3.1.1p1). This
4287/// routine will assert if passed a built-in type that isn't an integer or enum,
4288/// or if it is not canonicalized.
4289unsigned ASTContext::getIntegerRank(const Type *T) const {
4290  assert(T->isCanonicalUnqualified() && "T should be canonicalized");
4291
4292  switch (cast<BuiltinType>(T)->getKind()) {
4293  default: llvm_unreachable("getIntegerRank(): not a built-in integer");
4294  case BuiltinType::Bool:
4295    return 1 + (getIntWidth(BoolTy) << 3);
4296  case BuiltinType::Char_S:
4297  case BuiltinType::Char_U:
4298  case BuiltinType::SChar:
4299  case BuiltinType::UChar:
4300    return 2 + (getIntWidth(CharTy) << 3);
4301  case BuiltinType::Short:
4302  case BuiltinType::UShort:
4303    return 3 + (getIntWidth(ShortTy) << 3);
4304  case BuiltinType::Int:
4305  case BuiltinType::UInt:
4306    return 4 + (getIntWidth(IntTy) << 3);
4307  case BuiltinType::Long:
4308  case BuiltinType::ULong:
4309    return 5 + (getIntWidth(LongTy) << 3);
4310  case BuiltinType::LongLong:
4311  case BuiltinType::ULongLong:
4312    return 6 + (getIntWidth(LongLongTy) << 3);
4313  case BuiltinType::Int128:
4314  case BuiltinType::UInt128:
4315    return 7 + (getIntWidth(Int128Ty) << 3);
4316  }
4317}
4318
4319/// \brief Whether this is a promotable bitfield reference according
4320/// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
4321///
4322/// \returns the type this bit-field will promote to, or NULL if no
4323/// promotion occurs.
4324QualType ASTContext::isPromotableBitField(Expr *E) const {
4325  if (E->isTypeDependent() || E->isValueDependent())
4326    return QualType();
4327
4328  FieldDecl *Field = E->getSourceBitField(); // FIXME: conditional bit-fields?
4329  if (!Field)
4330    return QualType();
4331
4332  QualType FT = Field->getType();
4333
4334  uint64_t BitWidth = Field->getBitWidthValue(*this);
4335  uint64_t IntSize = getTypeSize(IntTy);
4336  // GCC extension compatibility: if the bit-field size is less than or equal
4337  // to the size of int, it gets promoted no matter what its type is.
4338  // For instance, unsigned long bf : 4 gets promoted to signed int.
4339  if (BitWidth < IntSize)
4340    return IntTy;
4341
4342  if (BitWidth == IntSize)
4343    return FT->isSignedIntegerType() ? IntTy : UnsignedIntTy;
4344
4345  // Types bigger than int are not subject to promotions, and therefore act
4346  // like the base type.
4347  // FIXME: This doesn't quite match what gcc does, but what gcc does here
4348  // is ridiculous.
4349  return QualType();
4350}
4351
4352/// getPromotedIntegerType - Returns the type that Promotable will
4353/// promote to: C99 6.3.1.1p2, assuming that Promotable is a promotable
4354/// integer type.
4355QualType ASTContext::getPromotedIntegerType(QualType Promotable) const {
4356  assert(!Promotable.isNull());
4357  assert(Promotable->isPromotableIntegerType());
4358  if (const EnumType *ET = Promotable->getAs<EnumType>())
4359    return ET->getDecl()->getPromotionType();
4360
4361  if (const BuiltinType *BT = Promotable->getAs<BuiltinType>()) {
4362    // C++ [conv.prom]: A prvalue of type char16_t, char32_t, or wchar_t
4363    // (3.9.1) can be converted to a prvalue of the first of the following
4364    // types that can represent all the values of its underlying type:
4365    // int, unsigned int, long int, unsigned long int, long long int, or
4366    // unsigned long long int [...]
4367    // FIXME: Is there some better way to compute this?
4368    if (BT->getKind() == BuiltinType::WChar_S ||
4369        BT->getKind() == BuiltinType::WChar_U ||
4370        BT->getKind() == BuiltinType::Char16 ||
4371        BT->getKind() == BuiltinType::Char32) {
4372      bool FromIsSigned = BT->getKind() == BuiltinType::WChar_S;
4373      uint64_t FromSize = getTypeSize(BT);
4374      QualType PromoteTypes[] = { IntTy, UnsignedIntTy, LongTy, UnsignedLongTy,
4375                                  LongLongTy, UnsignedLongLongTy };
4376      for (size_t Idx = 0; Idx < llvm::array_lengthof(PromoteTypes); ++Idx) {
4377        uint64_t ToSize = getTypeSize(PromoteTypes[Idx]);
4378        if (FromSize < ToSize ||
4379            (FromSize == ToSize &&
4380             FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType()))
4381          return PromoteTypes[Idx];
4382      }
4383      llvm_unreachable("char type should fit into long long");
4384    }
4385  }
4386
4387  // At this point, we should have a signed or unsigned integer type.
4388  if (Promotable->isSignedIntegerType())
4389    return IntTy;
4390  uint64_t PromotableSize = getIntWidth(Promotable);
4391  uint64_t IntSize = getIntWidth(IntTy);
4392  assert(Promotable->isUnsignedIntegerType() && PromotableSize <= IntSize);
4393  return (PromotableSize != IntSize) ? IntTy : UnsignedIntTy;
4394}
4395
4396/// \brief Recurses in pointer/array types until it finds an objc retainable
4397/// type and returns its ownership.
4398Qualifiers::ObjCLifetime ASTContext::getInnerObjCOwnership(QualType T) const {
4399  while (!T.isNull()) {
4400    if (T.getObjCLifetime() != Qualifiers::OCL_None)
4401      return T.getObjCLifetime();
4402    if (T->isArrayType())
4403      T = getBaseElementType(T);
4404    else if (const PointerType *PT = T->getAs<PointerType>())
4405      T = PT->getPointeeType();
4406    else if (const ReferenceType *RT = T->getAs<ReferenceType>())
4407      T = RT->getPointeeType();
4408    else
4409      break;
4410  }
4411
4412  return Qualifiers::OCL_None;
4413}
4414
4415/// getIntegerTypeOrder - Returns the highest ranked integer type:
4416/// C99 6.3.1.8p1.  If LHS > RHS, return 1.  If LHS == RHS, return 0. If
4417/// LHS < RHS, return -1.
4418int ASTContext::getIntegerTypeOrder(QualType LHS, QualType RHS) const {
4419  const Type *LHSC = getCanonicalType(LHS).getTypePtr();
4420  const Type *RHSC = getCanonicalType(RHS).getTypePtr();
4421  if (LHSC == RHSC) return 0;
4422
4423  bool LHSUnsigned = LHSC->isUnsignedIntegerType();
4424  bool RHSUnsigned = RHSC->isUnsignedIntegerType();
4425
4426  unsigned LHSRank = getIntegerRank(LHSC);
4427  unsigned RHSRank = getIntegerRank(RHSC);
4428
4429  if (LHSUnsigned == RHSUnsigned) {  // Both signed or both unsigned.
4430    if (LHSRank == RHSRank) return 0;
4431    return LHSRank > RHSRank ? 1 : -1;
4432  }
4433
4434  // Otherwise, the LHS is signed and the RHS is unsigned or visa versa.
4435  if (LHSUnsigned) {
4436    // If the unsigned [LHS] type is larger, return it.
4437    if (LHSRank >= RHSRank)
4438      return 1;
4439
4440    // If the signed type can represent all values of the unsigned type, it
4441    // wins.  Because we are dealing with 2's complement and types that are
4442    // powers of two larger than each other, this is always safe.
4443    return -1;
4444  }
4445
4446  // If the unsigned [RHS] type is larger, return it.
4447  if (RHSRank >= LHSRank)
4448    return -1;
4449
4450  // If the signed type can represent all values of the unsigned type, it
4451  // wins.  Because we are dealing with 2's complement and types that are
4452  // powers of two larger than each other, this is always safe.
4453  return 1;
4454}
4455
4456static RecordDecl *
4457CreateRecordDecl(const ASTContext &Ctx, RecordDecl::TagKind TK,
4458                 DeclContext *DC, IdentifierInfo *Id) {
4459  SourceLocation Loc;
4460  if (Ctx.getLangOpts().CPlusPlus)
4461    return CXXRecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
4462  else
4463    return RecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
4464}
4465
4466// getCFConstantStringType - Return the type used for constant CFStrings.
4467QualType ASTContext::getCFConstantStringType() const {
4468  if (!CFConstantStringTypeDecl) {
4469    CFConstantStringTypeDecl =
4470      CreateRecordDecl(*this, TTK_Struct, TUDecl,
4471                       &Idents.get("NSConstantString"));
4472    CFConstantStringTypeDecl->startDefinition();
4473
4474    QualType FieldTypes[4];
4475
4476    // const int *isa;
4477    FieldTypes[0] = getPointerType(IntTy.withConst());
4478    // int flags;
4479    FieldTypes[1] = IntTy;
4480    // const char *str;
4481    FieldTypes[2] = getPointerType(CharTy.withConst());
4482    // long length;
4483    FieldTypes[3] = LongTy;
4484
4485    // Create fields
4486    for (unsigned i = 0; i < 4; ++i) {
4487      FieldDecl *Field = FieldDecl::Create(*this, CFConstantStringTypeDecl,
4488                                           SourceLocation(),
4489                                           SourceLocation(), 0,
4490                                           FieldTypes[i], /*TInfo=*/0,
4491                                           /*BitWidth=*/0,
4492                                           /*Mutable=*/false,
4493                                           ICIS_NoInit);
4494      Field->setAccess(AS_public);
4495      CFConstantStringTypeDecl->addDecl(Field);
4496    }
4497
4498    CFConstantStringTypeDecl->completeDefinition();
4499  }
4500
4501  return getTagDeclType(CFConstantStringTypeDecl);
4502}
4503
4504QualType ASTContext::getObjCSuperType() const {
4505  if (ObjCSuperType.isNull()) {
4506    RecordDecl *ObjCSuperTypeDecl  =
4507      CreateRecordDecl(*this, TTK_Struct, TUDecl, &Idents.get("objc_super"));
4508    TUDecl->addDecl(ObjCSuperTypeDecl);
4509    ObjCSuperType = getTagDeclType(ObjCSuperTypeDecl);
4510  }
4511  return ObjCSuperType;
4512}
4513
4514void ASTContext::setCFConstantStringType(QualType T) {
4515  const RecordType *Rec = T->getAs<RecordType>();
4516  assert(Rec && "Invalid CFConstantStringType");
4517  CFConstantStringTypeDecl = Rec->getDecl();
4518}
4519
4520QualType ASTContext::getBlockDescriptorType() const {
4521  if (BlockDescriptorType)
4522    return getTagDeclType(BlockDescriptorType);
4523
4524  RecordDecl *T;
4525  // FIXME: Needs the FlagAppleBlock bit.
4526  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
4527                       &Idents.get("__block_descriptor"));
4528  T->startDefinition();
4529
4530  QualType FieldTypes[] = {
4531    UnsignedLongTy,
4532    UnsignedLongTy,
4533  };
4534
4535  static const char *const FieldNames[] = {
4536    "reserved",
4537    "Size"
4538  };
4539
4540  for (size_t i = 0; i < 2; ++i) {
4541    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
4542                                         SourceLocation(),
4543                                         &Idents.get(FieldNames[i]),
4544                                         FieldTypes[i], /*TInfo=*/0,
4545                                         /*BitWidth=*/0,
4546                                         /*Mutable=*/false,
4547                                         ICIS_NoInit);
4548    Field->setAccess(AS_public);
4549    T->addDecl(Field);
4550  }
4551
4552  T->completeDefinition();
4553
4554  BlockDescriptorType = T;
4555
4556  return getTagDeclType(BlockDescriptorType);
4557}
4558
4559QualType ASTContext::getBlockDescriptorExtendedType() const {
4560  if (BlockDescriptorExtendedType)
4561    return getTagDeclType(BlockDescriptorExtendedType);
4562
4563  RecordDecl *T;
4564  // FIXME: Needs the FlagAppleBlock bit.
4565  T = CreateRecordDecl(*this, TTK_Struct, TUDecl,
4566                       &Idents.get("__block_descriptor_withcopydispose"));
4567  T->startDefinition();
4568
4569  QualType FieldTypes[] = {
4570    UnsignedLongTy,
4571    UnsignedLongTy,
4572    getPointerType(VoidPtrTy),
4573    getPointerType(VoidPtrTy)
4574  };
4575
4576  static const char *const FieldNames[] = {
4577    "reserved",
4578    "Size",
4579    "CopyFuncPtr",
4580    "DestroyFuncPtr"
4581  };
4582
4583  for (size_t i = 0; i < 4; ++i) {
4584    FieldDecl *Field = FieldDecl::Create(*this, T, SourceLocation(),
4585                                         SourceLocation(),
4586                                         &Idents.get(FieldNames[i]),
4587                                         FieldTypes[i], /*TInfo=*/0,
4588                                         /*BitWidth=*/0,
4589                                         /*Mutable=*/false,
4590                                         ICIS_NoInit);
4591    Field->setAccess(AS_public);
4592    T->addDecl(Field);
4593  }
4594
4595  T->completeDefinition();
4596
4597  BlockDescriptorExtendedType = T;
4598
4599  return getTagDeclType(BlockDescriptorExtendedType);
4600}
4601
4602/// BlockRequiresCopying - Returns true if byref variable "D" of type "Ty"
4603/// requires copy/dispose. Note that this must match the logic
4604/// in buildByrefHelpers.
4605bool ASTContext::BlockRequiresCopying(QualType Ty,
4606                                      const VarDecl *D) {
4607  if (const CXXRecordDecl *record = Ty->getAsCXXRecordDecl()) {
4608    const Expr *copyExpr = getBlockVarCopyInits(D);
4609    if (!copyExpr && record->hasTrivialDestructor()) return false;
4610
4611    return true;
4612  }
4613
4614  if (!Ty->isObjCRetainableType()) return false;
4615
4616  Qualifiers qs = Ty.getQualifiers();
4617
4618  // If we have lifetime, that dominates.
4619  if (Qualifiers::ObjCLifetime lifetime = qs.getObjCLifetime()) {
4620    assert(getLangOpts().ObjCAutoRefCount);
4621
4622    switch (lifetime) {
4623      case Qualifiers::OCL_None: llvm_unreachable("impossible");
4624
4625      // These are just bits as far as the runtime is concerned.
4626      case Qualifiers::OCL_ExplicitNone:
4627      case Qualifiers::OCL_Autoreleasing:
4628        return false;
4629
4630      // Tell the runtime that this is ARC __weak, called by the
4631      // byref routines.
4632      case Qualifiers::OCL_Weak:
4633      // ARC __strong __block variables need to be retained.
4634      case Qualifiers::OCL_Strong:
4635        return true;
4636    }
4637    llvm_unreachable("fell out of lifetime switch!");
4638  }
4639  return (Ty->isBlockPointerType() || isObjCNSObjectType(Ty) ||
4640          Ty->isObjCObjectPointerType());
4641}
4642
4643bool ASTContext::getByrefLifetime(QualType Ty,
4644                              Qualifiers::ObjCLifetime &LifeTime,
4645                              bool &HasByrefExtendedLayout) const {
4646
4647  if (!getLangOpts().ObjC1 ||
4648      getLangOpts().getGC() != LangOptions::NonGC)
4649    return false;
4650
4651  HasByrefExtendedLayout = false;
4652  if (Ty->isRecordType()) {
4653    HasByrefExtendedLayout = true;
4654    LifeTime = Qualifiers::OCL_None;
4655  }
4656  else if (getLangOpts().ObjCAutoRefCount)
4657    LifeTime = Ty.getObjCLifetime();
4658  // MRR.
4659  else if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
4660    LifeTime = Qualifiers::OCL_ExplicitNone;
4661  else
4662    LifeTime = Qualifiers::OCL_None;
4663  return true;
4664}
4665
4666TypedefDecl *ASTContext::getObjCInstanceTypeDecl() {
4667  if (!ObjCInstanceTypeDecl)
4668    ObjCInstanceTypeDecl = TypedefDecl::Create(*this,
4669                                               getTranslationUnitDecl(),
4670                                               SourceLocation(),
4671                                               SourceLocation(),
4672                                               &Idents.get("instancetype"),
4673                                     getTrivialTypeSourceInfo(getObjCIdType()));
4674  return ObjCInstanceTypeDecl;
4675}
4676
4677// This returns true if a type has been typedefed to BOOL:
4678// typedef <type> BOOL;
4679static bool isTypeTypedefedAsBOOL(QualType T) {
4680  if (const TypedefType *TT = dyn_cast<TypedefType>(T))
4681    if (IdentifierInfo *II = TT->getDecl()->getIdentifier())
4682      return II->isStr("BOOL");
4683
4684  return false;
4685}
4686
4687/// getObjCEncodingTypeSize returns size of type for objective-c encoding
4688/// purpose.
4689CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
4690  if (!type->isIncompleteArrayType() && type->isIncompleteType())
4691    return CharUnits::Zero();
4692
4693  CharUnits sz = getTypeSizeInChars(type);
4694
4695  // Make all integer and enum types at least as large as an int
4696  if (sz.isPositive() && type->isIntegralOrEnumerationType())
4697    sz = std::max(sz, getTypeSizeInChars(IntTy));
4698  // Treat arrays as pointers, since that's how they're passed in.
4699  else if (type->isArrayType())
4700    sz = getTypeSizeInChars(VoidPtrTy);
4701  return sz;
4702}
4703
4704static inline
4705std::string charUnitsToString(const CharUnits &CU) {
4706  return llvm::itostr(CU.getQuantity());
4707}
4708
4709/// getObjCEncodingForBlock - Return the encoded type for this block
4710/// declaration.
4711std::string ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr) const {
4712  std::string S;
4713
4714  const BlockDecl *Decl = Expr->getBlockDecl();
4715  QualType BlockTy =
4716      Expr->getType()->getAs<BlockPointerType>()->getPointeeType();
4717  // Encode result type.
4718  if (getLangOpts().EncodeExtendedBlockSig)
4719    getObjCEncodingForMethodParameter(Decl::OBJC_TQ_None,
4720                            BlockTy->getAs<FunctionType>()->getResultType(),
4721                            S, true /*Extended*/);
4722  else
4723    getObjCEncodingForType(BlockTy->getAs<FunctionType>()->getResultType(),
4724                           S);
4725  // Compute size of all parameters.
4726  // Start with computing size of a pointer in number of bytes.
4727  // FIXME: There might(should) be a better way of doing this computation!
4728  SourceLocation Loc;
4729  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4730  CharUnits ParmOffset = PtrSize;
4731  for (BlockDecl::param_const_iterator PI = Decl->param_begin(),
4732       E = Decl->param_end(); PI != E; ++PI) {
4733    QualType PType = (*PI)->getType();
4734    CharUnits sz = getObjCEncodingTypeSize(PType);
4735    if (sz.isZero())
4736      continue;
4737    assert (sz.isPositive() && "BlockExpr - Incomplete param type");
4738    ParmOffset += sz;
4739  }
4740  // Size of the argument frame
4741  S += charUnitsToString(ParmOffset);
4742  // Block pointer and offset.
4743  S += "@?0";
4744
4745  // Argument types.
4746  ParmOffset = PtrSize;
4747  for (BlockDecl::param_const_iterator PI = Decl->param_begin(), E =
4748       Decl->param_end(); PI != E; ++PI) {
4749    ParmVarDecl *PVDecl = *PI;
4750    QualType PType = PVDecl->getOriginalType();
4751    if (const ArrayType *AT =
4752          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4753      // Use array's original type only if it has known number of
4754      // elements.
4755      if (!isa<ConstantArrayType>(AT))
4756        PType = PVDecl->getType();
4757    } else if (PType->isFunctionType())
4758      PType = PVDecl->getType();
4759    if (getLangOpts().EncodeExtendedBlockSig)
4760      getObjCEncodingForMethodParameter(Decl::OBJC_TQ_None, PType,
4761                                      S, true /*Extended*/);
4762    else
4763      getObjCEncodingForType(PType, S);
4764    S += charUnitsToString(ParmOffset);
4765    ParmOffset += getObjCEncodingTypeSize(PType);
4766  }
4767
4768  return S;
4769}
4770
4771bool ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
4772                                                std::string& S) {
4773  // Encode result type.
4774  getObjCEncodingForType(Decl->getResultType(), S);
4775  CharUnits ParmOffset;
4776  // Compute size of all parameters.
4777  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4778       E = Decl->param_end(); PI != E; ++PI) {
4779    QualType PType = (*PI)->getType();
4780    CharUnits sz = getObjCEncodingTypeSize(PType);
4781    if (sz.isZero())
4782      continue;
4783
4784    assert (sz.isPositive() &&
4785        "getObjCEncodingForFunctionDecl - Incomplete param type");
4786    ParmOffset += sz;
4787  }
4788  S += charUnitsToString(ParmOffset);
4789  ParmOffset = CharUnits::Zero();
4790
4791  // Argument types.
4792  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
4793       E = Decl->param_end(); PI != E; ++PI) {
4794    ParmVarDecl *PVDecl = *PI;
4795    QualType PType = PVDecl->getOriginalType();
4796    if (const ArrayType *AT =
4797          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4798      // Use array's original type only if it has known number of
4799      // elements.
4800      if (!isa<ConstantArrayType>(AT))
4801        PType = PVDecl->getType();
4802    } else if (PType->isFunctionType())
4803      PType = PVDecl->getType();
4804    getObjCEncodingForType(PType, S);
4805    S += charUnitsToString(ParmOffset);
4806    ParmOffset += getObjCEncodingTypeSize(PType);
4807  }
4808
4809  return false;
4810}
4811
4812/// getObjCEncodingForMethodParameter - Return the encoded type for a single
4813/// method parameter or return type. If Extended, include class names and
4814/// block object types.
4815void ASTContext::getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
4816                                                   QualType T, std::string& S,
4817                                                   bool Extended) const {
4818  // Encode type qualifer, 'in', 'inout', etc. for the parameter.
4819  getObjCEncodingForTypeQualifier(QT, S);
4820  // Encode parameter type.
4821  getObjCEncodingForTypeImpl(T, S, true, true, 0,
4822                             true     /*OutermostType*/,
4823                             false    /*EncodingProperty*/,
4824                             false    /*StructField*/,
4825                             Extended /*EncodeBlockParameters*/,
4826                             Extended /*EncodeClassNames*/);
4827}
4828
4829/// getObjCEncodingForMethodDecl - Return the encoded type for this method
4830/// declaration.
4831bool ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
4832                                              std::string& S,
4833                                              bool Extended) const {
4834  // FIXME: This is not very efficient.
4835  // Encode return type.
4836  getObjCEncodingForMethodParameter(Decl->getObjCDeclQualifier(),
4837                                    Decl->getResultType(), S, Extended);
4838  // Compute size of all parameters.
4839  // Start with computing size of a pointer in number of bytes.
4840  // FIXME: There might(should) be a better way of doing this computation!
4841  SourceLocation Loc;
4842  CharUnits PtrSize = getTypeSizeInChars(VoidPtrTy);
4843  // The first two arguments (self and _cmd) are pointers; account for
4844  // their size.
4845  CharUnits ParmOffset = 2 * PtrSize;
4846  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4847       E = Decl->sel_param_end(); PI != E; ++PI) {
4848    QualType PType = (*PI)->getType();
4849    CharUnits sz = getObjCEncodingTypeSize(PType);
4850    if (sz.isZero())
4851      continue;
4852
4853    assert (sz.isPositive() &&
4854        "getObjCEncodingForMethodDecl - Incomplete param type");
4855    ParmOffset += sz;
4856  }
4857  S += charUnitsToString(ParmOffset);
4858  S += "@0:";
4859  S += charUnitsToString(PtrSize);
4860
4861  // Argument types.
4862  ParmOffset = 2 * PtrSize;
4863  for (ObjCMethodDecl::param_const_iterator PI = Decl->param_begin(),
4864       E = Decl->sel_param_end(); PI != E; ++PI) {
4865    const ParmVarDecl *PVDecl = *PI;
4866    QualType PType = PVDecl->getOriginalType();
4867    if (const ArrayType *AT =
4868          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
4869      // Use array's original type only if it has known number of
4870      // elements.
4871      if (!isa<ConstantArrayType>(AT))
4872        PType = PVDecl->getType();
4873    } else if (PType->isFunctionType())
4874      PType = PVDecl->getType();
4875    getObjCEncodingForMethodParameter(PVDecl->getObjCDeclQualifier(),
4876                                      PType, S, Extended);
4877    S += charUnitsToString(ParmOffset);
4878    ParmOffset += getObjCEncodingTypeSize(PType);
4879  }
4880
4881  return false;
4882}
4883
4884/// getObjCEncodingForPropertyDecl - Return the encoded type for this
4885/// property declaration. If non-NULL, Container must be either an
4886/// ObjCCategoryImplDecl or ObjCImplementationDecl; it should only be
4887/// NULL when getting encodings for protocol properties.
4888/// Property attributes are stored as a comma-delimited C string. The simple
4889/// attributes readonly and bycopy are encoded as single characters. The
4890/// parametrized attributes, getter=name, setter=name, and ivar=name, are
4891/// encoded as single characters, followed by an identifier. Property types
4892/// are also encoded as a parametrized attribute. The characters used to encode
4893/// these attributes are defined by the following enumeration:
4894/// @code
4895/// enum PropertyAttributes {
4896/// kPropertyReadOnly = 'R',   // property is read-only.
4897/// kPropertyBycopy = 'C',     // property is a copy of the value last assigned
4898/// kPropertyByref = '&',  // property is a reference to the value last assigned
4899/// kPropertyDynamic = 'D',    // property is dynamic
4900/// kPropertyGetter = 'G',     // followed by getter selector name
4901/// kPropertySetter = 'S',     // followed by setter selector name
4902/// kPropertyInstanceVariable = 'V'  // followed by instance variable  name
4903/// kPropertyType = 'T'              // followed by old-style type encoding.
4904/// kPropertyWeak = 'W'              // 'weak' property
4905/// kPropertyStrong = 'P'            // property GC'able
4906/// kPropertyNonAtomic = 'N'         // property non-atomic
4907/// };
4908/// @endcode
4909void ASTContext::getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
4910                                                const Decl *Container,
4911                                                std::string& S) const {
4912  // Collect information from the property implementation decl(s).
4913  bool Dynamic = false;
4914  ObjCPropertyImplDecl *SynthesizePID = 0;
4915
4916  // FIXME: Duplicated code due to poor abstraction.
4917  if (Container) {
4918    if (const ObjCCategoryImplDecl *CID =
4919        dyn_cast<ObjCCategoryImplDecl>(Container)) {
4920      for (ObjCCategoryImplDecl::propimpl_iterator
4921             i = CID->propimpl_begin(), e = CID->propimpl_end();
4922           i != e; ++i) {
4923        ObjCPropertyImplDecl *PID = *i;
4924        if (PID->getPropertyDecl() == PD) {
4925          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4926            Dynamic = true;
4927          } else {
4928            SynthesizePID = PID;
4929          }
4930        }
4931      }
4932    } else {
4933      const ObjCImplementationDecl *OID=cast<ObjCImplementationDecl>(Container);
4934      for (ObjCCategoryImplDecl::propimpl_iterator
4935             i = OID->propimpl_begin(), e = OID->propimpl_end();
4936           i != e; ++i) {
4937        ObjCPropertyImplDecl *PID = *i;
4938        if (PID->getPropertyDecl() == PD) {
4939          if (PID->getPropertyImplementation()==ObjCPropertyImplDecl::Dynamic) {
4940            Dynamic = true;
4941          } else {
4942            SynthesizePID = PID;
4943          }
4944        }
4945      }
4946    }
4947  }
4948
4949  // FIXME: This is not very efficient.
4950  S = "T";
4951
4952  // Encode result type.
4953  // GCC has some special rules regarding encoding of properties which
4954  // closely resembles encoding of ivars.
4955  getObjCEncodingForTypeImpl(PD->getType(), S, true, true, 0,
4956                             true /* outermost type */,
4957                             true /* encoding for property */);
4958
4959  if (PD->isReadOnly()) {
4960    S += ",R";
4961    if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_copy)
4962      S += ",C";
4963    if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_retain)
4964      S += ",&";
4965  } else {
4966    switch (PD->getSetterKind()) {
4967    case ObjCPropertyDecl::Assign: break;
4968    case ObjCPropertyDecl::Copy:   S += ",C"; break;
4969    case ObjCPropertyDecl::Retain: S += ",&"; break;
4970    case ObjCPropertyDecl::Weak:   S += ",W"; break;
4971    }
4972  }
4973
4974  // It really isn't clear at all what this means, since properties
4975  // are "dynamic by default".
4976  if (Dynamic)
4977    S += ",D";
4978
4979  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic)
4980    S += ",N";
4981
4982  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_getter) {
4983    S += ",G";
4984    S += PD->getGetterName().getAsString();
4985  }
4986
4987  if (PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_setter) {
4988    S += ",S";
4989    S += PD->getSetterName().getAsString();
4990  }
4991
4992  if (SynthesizePID) {
4993    const ObjCIvarDecl *OID = SynthesizePID->getPropertyIvarDecl();
4994    S += ",V";
4995    S += OID->getNameAsString();
4996  }
4997
4998  // FIXME: OBJCGC: weak & strong
4999}
5000
5001/// getLegacyIntegralTypeEncoding -
5002/// Another legacy compatibility encoding: 32-bit longs are encoded as
5003/// 'l' or 'L' , but not always.  For typedefs, we need to use
5004/// 'i' or 'I' instead if encoding a struct field, or a pointer!
5005///
5006void ASTContext::getLegacyIntegralTypeEncoding (QualType &PointeeTy) const {
5007  if (isa<TypedefType>(PointeeTy.getTypePtr())) {
5008    if (const BuiltinType *BT = PointeeTy->getAs<BuiltinType>()) {
5009      if (BT->getKind() == BuiltinType::ULong && getIntWidth(PointeeTy) == 32)
5010        PointeeTy = UnsignedIntTy;
5011      else
5012        if (BT->getKind() == BuiltinType::Long && getIntWidth(PointeeTy) == 32)
5013          PointeeTy = IntTy;
5014    }
5015  }
5016}
5017
5018void ASTContext::getObjCEncodingForType(QualType T, std::string& S,
5019                                        const FieldDecl *Field) const {
5020  // We follow the behavior of gcc, expanding structures which are
5021  // directly pointed to, and expanding embedded structures. Note that
5022  // these rules are sufficient to prevent recursive encoding of the
5023  // same type.
5024  getObjCEncodingForTypeImpl(T, S, true, true, Field,
5025                             true /* outermost type */);
5026}
5027
5028static char getObjCEncodingForPrimitiveKind(const ASTContext *C,
5029                                            BuiltinType::Kind kind) {
5030    switch (kind) {
5031    case BuiltinType::Void:       return 'v';
5032    case BuiltinType::Bool:       return 'B';
5033    case BuiltinType::Char_U:
5034    case BuiltinType::UChar:      return 'C';
5035    case BuiltinType::Char16:
5036    case BuiltinType::UShort:     return 'S';
5037    case BuiltinType::Char32:
5038    case BuiltinType::UInt:       return 'I';
5039    case BuiltinType::ULong:
5040        return C->getTargetInfo().getLongWidth() == 32 ? 'L' : 'Q';
5041    case BuiltinType::UInt128:    return 'T';
5042    case BuiltinType::ULongLong:  return 'Q';
5043    case BuiltinType::Char_S:
5044    case BuiltinType::SChar:      return 'c';
5045    case BuiltinType::Short:      return 's';
5046    case BuiltinType::WChar_S:
5047    case BuiltinType::WChar_U:
5048    case BuiltinType::Int:        return 'i';
5049    case BuiltinType::Long:
5050      return C->getTargetInfo().getLongWidth() == 32 ? 'l' : 'q';
5051    case BuiltinType::LongLong:   return 'q';
5052    case BuiltinType::Int128:     return 't';
5053    case BuiltinType::Float:      return 'f';
5054    case BuiltinType::Double:     return 'd';
5055    case BuiltinType::LongDouble: return 'D';
5056    case BuiltinType::NullPtr:    return '*'; // like char*
5057
5058    case BuiltinType::Half:
5059      // FIXME: potentially need @encodes for these!
5060      return ' ';
5061
5062    case BuiltinType::ObjCId:
5063    case BuiltinType::ObjCClass:
5064    case BuiltinType::ObjCSel:
5065      llvm_unreachable("@encoding ObjC primitive type");
5066
5067    // OpenCL and placeholder types don't need @encodings.
5068    case BuiltinType::OCLImage1d:
5069    case BuiltinType::OCLImage1dArray:
5070    case BuiltinType::OCLImage1dBuffer:
5071    case BuiltinType::OCLImage2d:
5072    case BuiltinType::OCLImage2dArray:
5073    case BuiltinType::OCLImage3d:
5074    case BuiltinType::OCLEvent:
5075    case BuiltinType::OCLSampler:
5076    case BuiltinType::Dependent:
5077#define BUILTIN_TYPE(KIND, ID)
5078#define PLACEHOLDER_TYPE(KIND, ID) \
5079    case BuiltinType::KIND:
5080#include "clang/AST/BuiltinTypes.def"
5081      llvm_unreachable("invalid builtin type for @encode");
5082    }
5083    llvm_unreachable("invalid BuiltinType::Kind value");
5084}
5085
5086static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
5087  EnumDecl *Enum = ET->getDecl();
5088
5089  // The encoding of an non-fixed enum type is always 'i', regardless of size.
5090  if (!Enum->isFixed())
5091    return 'i';
5092
5093  // The encoding of a fixed enum type matches its fixed underlying type.
5094  const BuiltinType *BT = Enum->getIntegerType()->castAs<BuiltinType>();
5095  return getObjCEncodingForPrimitiveKind(C, BT->getKind());
5096}
5097
5098static void EncodeBitField(const ASTContext *Ctx, std::string& S,
5099                           QualType T, const FieldDecl *FD) {
5100  assert(FD->isBitField() && "not a bitfield - getObjCEncodingForTypeImpl");
5101  S += 'b';
5102  // The NeXT runtime encodes bit fields as b followed by the number of bits.
5103  // The GNU runtime requires more information; bitfields are encoded as b,
5104  // then the offset (in bits) of the first element, then the type of the
5105  // bitfield, then the size in bits.  For example, in this structure:
5106  //
5107  // struct
5108  // {
5109  //    int integer;
5110  //    int flags:2;
5111  // };
5112  // On a 32-bit system, the encoding for flags would be b2 for the NeXT
5113  // runtime, but b32i2 for the GNU runtime.  The reason for this extra
5114  // information is not especially sensible, but we're stuck with it for
5115  // compatibility with GCC, although providing it breaks anything that
5116  // actually uses runtime introspection and wants to work on both runtimes...
5117  if (Ctx->getLangOpts().ObjCRuntime.isGNUFamily()) {
5118    const RecordDecl *RD = FD->getParent();
5119    const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
5120    S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
5121    if (const EnumType *ET = T->getAs<EnumType>())
5122      S += ObjCEncodingForEnumType(Ctx, ET);
5123    else {
5124      const BuiltinType *BT = T->castAs<BuiltinType>();
5125      S += getObjCEncodingForPrimitiveKind(Ctx, BT->getKind());
5126    }
5127  }
5128  S += llvm::utostr(FD->getBitWidthValue(*Ctx));
5129}
5130
5131// FIXME: Use SmallString for accumulating string.
5132void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
5133                                            bool ExpandPointedToStructures,
5134                                            bool ExpandStructures,
5135                                            const FieldDecl *FD,
5136                                            bool OutermostType,
5137                                            bool EncodingProperty,
5138                                            bool StructField,
5139                                            bool EncodeBlockParameters,
5140                                            bool EncodeClassNames,
5141                                            bool EncodePointerToObjCTypedef) const {
5142  CanQualType CT = getCanonicalType(T);
5143  switch (CT->getTypeClass()) {
5144  case Type::Builtin:
5145  case Type::Enum:
5146    if (FD && FD->isBitField())
5147      return EncodeBitField(this, S, T, FD);
5148    if (const BuiltinType *BT = dyn_cast<BuiltinType>(CT))
5149      S += getObjCEncodingForPrimitiveKind(this, BT->getKind());
5150    else
5151      S += ObjCEncodingForEnumType(this, cast<EnumType>(CT));
5152    return;
5153
5154  case Type::Complex: {
5155    const ComplexType *CT = T->castAs<ComplexType>();
5156    S += 'j';
5157    getObjCEncodingForTypeImpl(CT->getElementType(), S, false, false, 0, false,
5158                               false);
5159    return;
5160  }
5161
5162  case Type::Atomic: {
5163    const AtomicType *AT = T->castAs<AtomicType>();
5164    S += 'A';
5165    getObjCEncodingForTypeImpl(AT->getValueType(), S, false, false, 0,
5166                               false, false);
5167    return;
5168  }
5169
5170  // encoding for pointer or reference types.
5171  case Type::Pointer:
5172  case Type::LValueReference:
5173  case Type::RValueReference: {
5174    QualType PointeeTy;
5175    if (isa<PointerType>(CT)) {
5176      const PointerType *PT = T->castAs<PointerType>();
5177      if (PT->isObjCSelType()) {
5178        S += ':';
5179        return;
5180      }
5181      PointeeTy = PT->getPointeeType();
5182    } else {
5183      PointeeTy = T->castAs<ReferenceType>()->getPointeeType();
5184    }
5185
5186    bool isReadOnly = false;
5187    // For historical/compatibility reasons, the read-only qualifier of the
5188    // pointee gets emitted _before_ the '^'.  The read-only qualifier of
5189    // the pointer itself gets ignored, _unless_ we are looking at a typedef!
5190    // Also, do not emit the 'r' for anything but the outermost type!
5191    if (isa<TypedefType>(T.getTypePtr())) {
5192      if (OutermostType && T.isConstQualified()) {
5193        isReadOnly = true;
5194        S += 'r';
5195      }
5196    } else if (OutermostType) {
5197      QualType P = PointeeTy;
5198      while (P->getAs<PointerType>())
5199        P = P->getAs<PointerType>()->getPointeeType();
5200      if (P.isConstQualified()) {
5201        isReadOnly = true;
5202        S += 'r';
5203      }
5204    }
5205    if (isReadOnly) {
5206      // Another legacy compatibility encoding. Some ObjC qualifier and type
5207      // combinations need to be rearranged.
5208      // Rewrite "in const" from "nr" to "rn"
5209      if (StringRef(S).endswith("nr"))
5210        S.replace(S.end()-2, S.end(), "rn");
5211    }
5212
5213    if (PointeeTy->isCharType()) {
5214      // char pointer types should be encoded as '*' unless it is a
5215      // type that has been typedef'd to 'BOOL'.
5216      if (!isTypeTypedefedAsBOOL(PointeeTy)) {
5217        S += '*';
5218        return;
5219      }
5220    } else if (const RecordType *RTy = PointeeTy->getAs<RecordType>()) {
5221      // GCC binary compat: Need to convert "struct objc_class *" to "#".
5222      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_class")) {
5223        S += '#';
5224        return;
5225      }
5226      // GCC binary compat: Need to convert "struct objc_object *" to "@".
5227      if (RTy->getDecl()->getIdentifier() == &Idents.get("objc_object")) {
5228        S += '@';
5229        return;
5230      }
5231      // fall through...
5232    }
5233    S += '^';
5234    getLegacyIntegralTypeEncoding(PointeeTy);
5235
5236    getObjCEncodingForTypeImpl(PointeeTy, S, false, ExpandPointedToStructures,
5237                               NULL);
5238    return;
5239  }
5240
5241  case Type::ConstantArray:
5242  case Type::IncompleteArray:
5243  case Type::VariableArray: {
5244    const ArrayType *AT = cast<ArrayType>(CT);
5245
5246    if (isa<IncompleteArrayType>(AT) && !StructField) {
5247      // Incomplete arrays are encoded as a pointer to the array element.
5248      S += '^';
5249
5250      getObjCEncodingForTypeImpl(AT->getElementType(), S,
5251                                 false, ExpandStructures, FD);
5252    } else {
5253      S += '[';
5254
5255      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
5256        S += llvm::utostr(CAT->getSize().getZExtValue());
5257      else {
5258        //Variable length arrays are encoded as a regular array with 0 elements.
5259        assert((isa<VariableArrayType>(AT) || isa<IncompleteArrayType>(AT)) &&
5260               "Unknown array type!");
5261        S += '0';
5262      }
5263
5264      getObjCEncodingForTypeImpl(AT->getElementType(), S,
5265                                 false, ExpandStructures, FD);
5266      S += ']';
5267    }
5268    return;
5269  }
5270
5271  case Type::FunctionNoProto:
5272  case Type::FunctionProto:
5273    S += '?';
5274    return;
5275
5276  case Type::Record: {
5277    RecordDecl *RDecl = cast<RecordType>(CT)->getDecl();
5278    S += RDecl->isUnion() ? '(' : '{';
5279    // Anonymous structures print as '?'
5280    if (const IdentifierInfo *II = RDecl->getIdentifier()) {
5281      S += II->getName();
5282      if (ClassTemplateSpecializationDecl *Spec
5283          = dyn_cast<ClassTemplateSpecializationDecl>(RDecl)) {
5284        const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
5285        llvm::raw_string_ostream OS(S);
5286        TemplateSpecializationType::PrintTemplateArgumentList(OS,
5287                                            TemplateArgs.data(),
5288                                            TemplateArgs.size(),
5289                                            (*this).getPrintingPolicy());
5290      }
5291    } else {
5292      S += '?';
5293    }
5294    if (ExpandStructures) {
5295      S += '=';
5296      if (!RDecl->isUnion()) {
5297        getObjCEncodingForStructureImpl(RDecl, S, FD);
5298      } else {
5299        for (RecordDecl::field_iterator Field = RDecl->field_begin(),
5300                                     FieldEnd = RDecl->field_end();
5301             Field != FieldEnd; ++Field) {
5302          if (FD) {
5303            S += '"';
5304            S += Field->getNameAsString();
5305            S += '"';
5306          }
5307
5308          // Special case bit-fields.
5309          if (Field->isBitField()) {
5310            getObjCEncodingForTypeImpl(Field->getType(), S, false, true,
5311                                       *Field);
5312          } else {
5313            QualType qt = Field->getType();
5314            getLegacyIntegralTypeEncoding(qt);
5315            getObjCEncodingForTypeImpl(qt, S, false, true,
5316                                       FD, /*OutermostType*/false,
5317                                       /*EncodingProperty*/false,
5318                                       /*StructField*/true);
5319          }
5320        }
5321      }
5322    }
5323    S += RDecl->isUnion() ? ')' : '}';
5324    return;
5325  }
5326
5327  case Type::BlockPointer: {
5328    const BlockPointerType *BT = T->castAs<BlockPointerType>();
5329    S += "@?"; // Unlike a pointer-to-function, which is "^?".
5330    if (EncodeBlockParameters) {
5331      const FunctionType *FT = BT->getPointeeType()->castAs<FunctionType>();
5332
5333      S += '<';
5334      // Block return type
5335      getObjCEncodingForTypeImpl(FT->getResultType(), S,
5336                                 ExpandPointedToStructures, ExpandStructures,
5337                                 FD,
5338                                 false /* OutermostType */,
5339                                 EncodingProperty,
5340                                 false /* StructField */,
5341                                 EncodeBlockParameters,
5342                                 EncodeClassNames);
5343      // Block self
5344      S += "@?";
5345      // Block parameters
5346      if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT)) {
5347        for (FunctionProtoType::arg_type_iterator I = FPT->arg_type_begin(),
5348               E = FPT->arg_type_end(); I && (I != E); ++I) {
5349          getObjCEncodingForTypeImpl(*I, S,
5350                                     ExpandPointedToStructures,
5351                                     ExpandStructures,
5352                                     FD,
5353                                     false /* OutermostType */,
5354                                     EncodingProperty,
5355                                     false /* StructField */,
5356                                     EncodeBlockParameters,
5357                                     EncodeClassNames);
5358        }
5359      }
5360      S += '>';
5361    }
5362    return;
5363  }
5364
5365  case Type::ObjCObject:
5366  case Type::ObjCInterface: {
5367    // Ignore protocol qualifiers when mangling at this level.
5368    T = T->castAs<ObjCObjectType>()->getBaseType();
5369
5370    // The assumption seems to be that this assert will succeed
5371    // because nested levels will have filtered out 'id' and 'Class'.
5372    const ObjCInterfaceType *OIT = T->castAs<ObjCInterfaceType>();
5373    // @encode(class_name)
5374    ObjCInterfaceDecl *OI = OIT->getDecl();
5375    S += '{';
5376    const IdentifierInfo *II = OI->getIdentifier();
5377    S += II->getName();
5378    S += '=';
5379    SmallVector<const ObjCIvarDecl*, 32> Ivars;
5380    DeepCollectObjCIvars(OI, true, Ivars);
5381    for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
5382      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
5383      if (Field->isBitField())
5384        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
5385      else
5386        getObjCEncodingForTypeImpl(Field->getType(), S, false, true, FD,
5387                                   false, false, false, false, false,
5388                                   EncodePointerToObjCTypedef);
5389    }
5390    S += '}';
5391    return;
5392  }
5393
5394  case Type::ObjCObjectPointer: {
5395    const ObjCObjectPointerType *OPT = T->castAs<ObjCObjectPointerType>();
5396    if (OPT->isObjCIdType()) {
5397      S += '@';
5398      return;
5399    }
5400
5401    if (OPT->isObjCClassType() || OPT->isObjCQualifiedClassType()) {
5402      // FIXME: Consider if we need to output qualifiers for 'Class<p>'.
5403      // Since this is a binary compatibility issue, need to consult with runtime
5404      // folks. Fortunately, this is a *very* obsure construct.
5405      S += '#';
5406      return;
5407    }
5408
5409    if (OPT->isObjCQualifiedIdType()) {
5410      getObjCEncodingForTypeImpl(getObjCIdType(), S,
5411                                 ExpandPointedToStructures,
5412                                 ExpandStructures, FD);
5413      if (FD || EncodingProperty || EncodeClassNames) {
5414        // Note that we do extended encoding of protocol qualifer list
5415        // Only when doing ivar or property encoding.
5416        S += '"';
5417        for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
5418             E = OPT->qual_end(); I != E; ++I) {
5419          S += '<';
5420          S += (*I)->getNameAsString();
5421          S += '>';
5422        }
5423        S += '"';
5424      }
5425      return;
5426    }
5427
5428    QualType PointeeTy = OPT->getPointeeType();
5429    if (!EncodingProperty &&
5430        isa<TypedefType>(PointeeTy.getTypePtr()) &&
5431        !EncodePointerToObjCTypedef) {
5432      // Another historical/compatibility reason.
5433      // We encode the underlying type which comes out as
5434      // {...};
5435      S += '^';
5436      if (FD && OPT->getInterfaceDecl()) {
5437        // Prevent recursive encoding of fields in some rare cases.
5438        ObjCInterfaceDecl *OI = OPT->getInterfaceDecl();
5439        SmallVector<const ObjCIvarDecl*, 32> Ivars;
5440        DeepCollectObjCIvars(OI, true, Ivars);
5441        for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
5442          if (cast<FieldDecl>(Ivars[i]) == FD) {
5443            S += '{';
5444            S += OI->getIdentifier()->getName();
5445            S += '}';
5446            return;
5447          }
5448        }
5449      }
5450      getObjCEncodingForTypeImpl(PointeeTy, S,
5451                                 false, ExpandPointedToStructures,
5452                                 NULL,
5453                                 false, false, false, false, false,
5454                                 /*EncodePointerToObjCTypedef*/true);
5455      return;
5456    }
5457
5458    S += '@';
5459    if (OPT->getInterfaceDecl() &&
5460        (FD || EncodingProperty || EncodeClassNames)) {
5461      S += '"';
5462      S += OPT->getInterfaceDecl()->getIdentifier()->getName();
5463      for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
5464           E = OPT->qual_end(); I != E; ++I) {
5465        S += '<';
5466        S += (*I)->getNameAsString();
5467        S += '>';
5468      }
5469      S += '"';
5470    }
5471    return;
5472  }
5473
5474  // gcc just blithely ignores member pointers.
5475  // FIXME: we shoul do better than that.  'M' is available.
5476  case Type::MemberPointer:
5477    return;
5478
5479  case Type::Vector:
5480  case Type::ExtVector:
5481    // This matches gcc's encoding, even though technically it is
5482    // insufficient.
5483    // FIXME. We should do a better job than gcc.
5484    return;
5485
5486  case Type::Auto:
5487    // We could see an undeduced auto type here during error recovery.
5488    // Just ignore it.
5489    return;
5490
5491#define ABSTRACT_TYPE(KIND, BASE)
5492#define TYPE(KIND, BASE)
5493#define DEPENDENT_TYPE(KIND, BASE) \
5494  case Type::KIND:
5495#define NON_CANONICAL_TYPE(KIND, BASE) \
5496  case Type::KIND:
5497#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(KIND, BASE) \
5498  case Type::KIND:
5499#include "clang/AST/TypeNodes.def"
5500    llvm_unreachable("@encode for dependent type!");
5501  }
5502  llvm_unreachable("bad type kind!");
5503}
5504
5505void ASTContext::getObjCEncodingForStructureImpl(RecordDecl *RDecl,
5506                                                 std::string &S,
5507                                                 const FieldDecl *FD,
5508                                                 bool includeVBases) const {
5509  assert(RDecl && "Expected non-null RecordDecl");
5510  assert(!RDecl->isUnion() && "Should not be called for unions");
5511  if (!RDecl->getDefinition())
5512    return;
5513
5514  CXXRecordDecl *CXXRec = dyn_cast<CXXRecordDecl>(RDecl);
5515  std::multimap<uint64_t, NamedDecl *> FieldOrBaseOffsets;
5516  const ASTRecordLayout &layout = getASTRecordLayout(RDecl);
5517
5518  if (CXXRec) {
5519    for (CXXRecordDecl::base_class_iterator
5520           BI = CXXRec->bases_begin(),
5521           BE = CXXRec->bases_end(); BI != BE; ++BI) {
5522      if (!BI->isVirtual()) {
5523        CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
5524        if (base->isEmpty())
5525          continue;
5526        uint64_t offs = toBits(layout.getBaseClassOffset(base));
5527        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5528                                  std::make_pair(offs, base));
5529      }
5530    }
5531  }
5532
5533  unsigned i = 0;
5534  for (RecordDecl::field_iterator Field = RDecl->field_begin(),
5535                               FieldEnd = RDecl->field_end();
5536       Field != FieldEnd; ++Field, ++i) {
5537    uint64_t offs = layout.getFieldOffset(i);
5538    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5539                              std::make_pair(offs, *Field));
5540  }
5541
5542  if (CXXRec && includeVBases) {
5543    for (CXXRecordDecl::base_class_iterator
5544           BI = CXXRec->vbases_begin(),
5545           BE = CXXRec->vbases_end(); BI != BE; ++BI) {
5546      CXXRecordDecl *base = BI->getType()->getAsCXXRecordDecl();
5547      if (base->isEmpty())
5548        continue;
5549      uint64_t offs = toBits(layout.getVBaseClassOffset(base));
5550      if (FieldOrBaseOffsets.find(offs) == FieldOrBaseOffsets.end())
5551        FieldOrBaseOffsets.insert(FieldOrBaseOffsets.end(),
5552                                  std::make_pair(offs, base));
5553    }
5554  }
5555
5556  CharUnits size;
5557  if (CXXRec) {
5558    size = includeVBases ? layout.getSize() : layout.getNonVirtualSize();
5559  } else {
5560    size = layout.getSize();
5561  }
5562
5563  uint64_t CurOffs = 0;
5564  std::multimap<uint64_t, NamedDecl *>::iterator
5565    CurLayObj = FieldOrBaseOffsets.begin();
5566
5567  if (CXXRec && CXXRec->isDynamicClass() &&
5568      (CurLayObj == FieldOrBaseOffsets.end() || CurLayObj->first != 0)) {
5569    if (FD) {
5570      S += "\"_vptr$";
5571      std::string recname = CXXRec->getNameAsString();
5572      if (recname.empty()) recname = "?";
5573      S += recname;
5574      S += '"';
5575    }
5576    S += "^^?";
5577    CurOffs += getTypeSize(VoidPtrTy);
5578  }
5579
5580  if (!RDecl->hasFlexibleArrayMember()) {
5581    // Mark the end of the structure.
5582    uint64_t offs = toBits(size);
5583    FieldOrBaseOffsets.insert(FieldOrBaseOffsets.upper_bound(offs),
5584                              std::make_pair(offs, (NamedDecl*)0));
5585  }
5586
5587  for (; CurLayObj != FieldOrBaseOffsets.end(); ++CurLayObj) {
5588    assert(CurOffs <= CurLayObj->first);
5589
5590    if (CurOffs < CurLayObj->first) {
5591      uint64_t padding = CurLayObj->first - CurOffs;
5592      // FIXME: There doesn't seem to be a way to indicate in the encoding that
5593      // packing/alignment of members is different that normal, in which case
5594      // the encoding will be out-of-sync with the real layout.
5595      // If the runtime switches to just consider the size of types without
5596      // taking into account alignment, we could make padding explicit in the
5597      // encoding (e.g. using arrays of chars). The encoding strings would be
5598      // longer then though.
5599      CurOffs += padding;
5600    }
5601
5602    NamedDecl *dcl = CurLayObj->second;
5603    if (dcl == 0)
5604      break; // reached end of structure.
5605
5606    if (CXXRecordDecl *base = dyn_cast<CXXRecordDecl>(dcl)) {
5607      // We expand the bases without their virtual bases since those are going
5608      // in the initial structure. Note that this differs from gcc which
5609      // expands virtual bases each time one is encountered in the hierarchy,
5610      // making the encoding type bigger than it really is.
5611      getObjCEncodingForStructureImpl(base, S, FD, /*includeVBases*/false);
5612      assert(!base->isEmpty());
5613      CurOffs += toBits(getASTRecordLayout(base).getNonVirtualSize());
5614    } else {
5615      FieldDecl *field = cast<FieldDecl>(dcl);
5616      if (FD) {
5617        S += '"';
5618        S += field->getNameAsString();
5619        S += '"';
5620      }
5621
5622      if (field->isBitField()) {
5623        EncodeBitField(this, S, field->getType(), field);
5624        CurOffs += field->getBitWidthValue(*this);
5625      } else {
5626        QualType qt = field->getType();
5627        getLegacyIntegralTypeEncoding(qt);
5628        getObjCEncodingForTypeImpl(qt, S, false, true, FD,
5629                                   /*OutermostType*/false,
5630                                   /*EncodingProperty*/false,
5631                                   /*StructField*/true);
5632        CurOffs += getTypeSize(field->getType());
5633      }
5634    }
5635  }
5636}
5637
5638void ASTContext::getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
5639                                                 std::string& S) const {
5640  if (QT & Decl::OBJC_TQ_In)
5641    S += 'n';
5642  if (QT & Decl::OBJC_TQ_Inout)
5643    S += 'N';
5644  if (QT & Decl::OBJC_TQ_Out)
5645    S += 'o';
5646  if (QT & Decl::OBJC_TQ_Bycopy)
5647    S += 'O';
5648  if (QT & Decl::OBJC_TQ_Byref)
5649    S += 'R';
5650  if (QT & Decl::OBJC_TQ_Oneway)
5651    S += 'V';
5652}
5653
5654TypedefDecl *ASTContext::getObjCIdDecl() const {
5655  if (!ObjCIdDecl) {
5656    QualType T = getObjCObjectType(ObjCBuiltinIdTy, 0, 0);
5657    T = getObjCObjectPointerType(T);
5658    TypeSourceInfo *IdInfo = getTrivialTypeSourceInfo(T);
5659    ObjCIdDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
5660                                     getTranslationUnitDecl(),
5661                                     SourceLocation(), SourceLocation(),
5662                                     &Idents.get("id"), IdInfo);
5663  }
5664
5665  return ObjCIdDecl;
5666}
5667
5668TypedefDecl *ASTContext::getObjCSelDecl() const {
5669  if (!ObjCSelDecl) {
5670    QualType SelT = getPointerType(ObjCBuiltinSelTy);
5671    TypeSourceInfo *SelInfo = getTrivialTypeSourceInfo(SelT);
5672    ObjCSelDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
5673                                      getTranslationUnitDecl(),
5674                                      SourceLocation(), SourceLocation(),
5675                                      &Idents.get("SEL"), SelInfo);
5676  }
5677  return ObjCSelDecl;
5678}
5679
5680TypedefDecl *ASTContext::getObjCClassDecl() const {
5681  if (!ObjCClassDecl) {
5682    QualType T = getObjCObjectType(ObjCBuiltinClassTy, 0, 0);
5683    T = getObjCObjectPointerType(T);
5684    TypeSourceInfo *ClassInfo = getTrivialTypeSourceInfo(T);
5685    ObjCClassDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
5686                                        getTranslationUnitDecl(),
5687                                        SourceLocation(), SourceLocation(),
5688                                        &Idents.get("Class"), ClassInfo);
5689  }
5690
5691  return ObjCClassDecl;
5692}
5693
5694ObjCInterfaceDecl *ASTContext::getObjCProtocolDecl() const {
5695  if (!ObjCProtocolClassDecl) {
5696    ObjCProtocolClassDecl
5697      = ObjCInterfaceDecl::Create(*this, getTranslationUnitDecl(),
5698                                  SourceLocation(),
5699                                  &Idents.get("Protocol"),
5700                                  /*PrevDecl=*/0,
5701                                  SourceLocation(), true);
5702  }
5703
5704  return ObjCProtocolClassDecl;
5705}
5706
5707//===----------------------------------------------------------------------===//
5708// __builtin_va_list Construction Functions
5709//===----------------------------------------------------------------------===//
5710
5711static TypedefDecl *CreateCharPtrBuiltinVaListDecl(const ASTContext *Context) {
5712  // typedef char* __builtin_va_list;
5713  QualType CharPtrType = Context->getPointerType(Context->CharTy);
5714  TypeSourceInfo *TInfo
5715    = Context->getTrivialTypeSourceInfo(CharPtrType);
5716
5717  TypedefDecl *VaListTypeDecl
5718    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5719                          Context->getTranslationUnitDecl(),
5720                          SourceLocation(), SourceLocation(),
5721                          &Context->Idents.get("__builtin_va_list"),
5722                          TInfo);
5723  return VaListTypeDecl;
5724}
5725
5726static TypedefDecl *CreateVoidPtrBuiltinVaListDecl(const ASTContext *Context) {
5727  // typedef void* __builtin_va_list;
5728  QualType VoidPtrType = Context->getPointerType(Context->VoidTy);
5729  TypeSourceInfo *TInfo
5730    = Context->getTrivialTypeSourceInfo(VoidPtrType);
5731
5732  TypedefDecl *VaListTypeDecl
5733    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5734                          Context->getTranslationUnitDecl(),
5735                          SourceLocation(), SourceLocation(),
5736                          &Context->Idents.get("__builtin_va_list"),
5737                          TInfo);
5738  return VaListTypeDecl;
5739}
5740
5741static TypedefDecl *
5742CreateAArch64ABIBuiltinVaListDecl(const ASTContext *Context) {
5743  RecordDecl *VaListTagDecl;
5744  if (Context->getLangOpts().CPlusPlus) {
5745    // namespace std { struct __va_list {
5746    NamespaceDecl *NS;
5747    NS = NamespaceDecl::Create(const_cast<ASTContext &>(*Context),
5748                               Context->getTranslationUnitDecl(),
5749                               /*Inline*/false, SourceLocation(),
5750                               SourceLocation(), &Context->Idents.get("std"),
5751                               /*PrevDecl*/0);
5752
5753    VaListTagDecl = CXXRecordDecl::Create(*Context, TTK_Struct,
5754                                          Context->getTranslationUnitDecl(),
5755                                          SourceLocation(), SourceLocation(),
5756                                          &Context->Idents.get("__va_list"));
5757    VaListTagDecl->setDeclContext(NS);
5758  } else {
5759    // struct __va_list
5760    VaListTagDecl = CreateRecordDecl(*Context, TTK_Struct,
5761                                   Context->getTranslationUnitDecl(),
5762                                   &Context->Idents.get("__va_list"));
5763  }
5764
5765  VaListTagDecl->startDefinition();
5766
5767  const size_t NumFields = 5;
5768  QualType FieldTypes[NumFields];
5769  const char *FieldNames[NumFields];
5770
5771  // void *__stack;
5772  FieldTypes[0] = Context->getPointerType(Context->VoidTy);
5773  FieldNames[0] = "__stack";
5774
5775  // void *__gr_top;
5776  FieldTypes[1] = Context->getPointerType(Context->VoidTy);
5777  FieldNames[1] = "__gr_top";
5778
5779  // void *__vr_top;
5780  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
5781  FieldNames[2] = "__vr_top";
5782
5783  // int __gr_offs;
5784  FieldTypes[3] = Context->IntTy;
5785  FieldNames[3] = "__gr_offs";
5786
5787  // int __vr_offs;
5788  FieldTypes[4] = Context->IntTy;
5789  FieldNames[4] = "__vr_offs";
5790
5791  // Create fields
5792  for (unsigned i = 0; i < NumFields; ++i) {
5793    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
5794                                         VaListTagDecl,
5795                                         SourceLocation(),
5796                                         SourceLocation(),
5797                                         &Context->Idents.get(FieldNames[i]),
5798                                         FieldTypes[i], /*TInfo=*/0,
5799                                         /*BitWidth=*/0,
5800                                         /*Mutable=*/false,
5801                                         ICIS_NoInit);
5802    Field->setAccess(AS_public);
5803    VaListTagDecl->addDecl(Field);
5804  }
5805  VaListTagDecl->completeDefinition();
5806  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
5807  Context->VaListTagTy = VaListTagType;
5808
5809  // } __builtin_va_list;
5810  TypedefDecl *VaListTypedefDecl
5811    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5812                          Context->getTranslationUnitDecl(),
5813                          SourceLocation(), SourceLocation(),
5814                          &Context->Idents.get("__builtin_va_list"),
5815                          Context->getTrivialTypeSourceInfo(VaListTagType));
5816
5817  return VaListTypedefDecl;
5818}
5819
5820static TypedefDecl *CreatePowerABIBuiltinVaListDecl(const ASTContext *Context) {
5821  // typedef struct __va_list_tag {
5822  RecordDecl *VaListTagDecl;
5823
5824  VaListTagDecl = CreateRecordDecl(*Context, TTK_Struct,
5825                                   Context->getTranslationUnitDecl(),
5826                                   &Context->Idents.get("__va_list_tag"));
5827  VaListTagDecl->startDefinition();
5828
5829  const size_t NumFields = 5;
5830  QualType FieldTypes[NumFields];
5831  const char *FieldNames[NumFields];
5832
5833  //   unsigned char gpr;
5834  FieldTypes[0] = Context->UnsignedCharTy;
5835  FieldNames[0] = "gpr";
5836
5837  //   unsigned char fpr;
5838  FieldTypes[1] = Context->UnsignedCharTy;
5839  FieldNames[1] = "fpr";
5840
5841  //   unsigned short reserved;
5842  FieldTypes[2] = Context->UnsignedShortTy;
5843  FieldNames[2] = "reserved";
5844
5845  //   void* overflow_arg_area;
5846  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
5847  FieldNames[3] = "overflow_arg_area";
5848
5849  //   void* reg_save_area;
5850  FieldTypes[4] = Context->getPointerType(Context->VoidTy);
5851  FieldNames[4] = "reg_save_area";
5852
5853  // Create fields
5854  for (unsigned i = 0; i < NumFields; ++i) {
5855    FieldDecl *Field = FieldDecl::Create(*Context, VaListTagDecl,
5856                                         SourceLocation(),
5857                                         SourceLocation(),
5858                                         &Context->Idents.get(FieldNames[i]),
5859                                         FieldTypes[i], /*TInfo=*/0,
5860                                         /*BitWidth=*/0,
5861                                         /*Mutable=*/false,
5862                                         ICIS_NoInit);
5863    Field->setAccess(AS_public);
5864    VaListTagDecl->addDecl(Field);
5865  }
5866  VaListTagDecl->completeDefinition();
5867  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
5868  Context->VaListTagTy = VaListTagType;
5869
5870  // } __va_list_tag;
5871  TypedefDecl *VaListTagTypedefDecl
5872    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5873                          Context->getTranslationUnitDecl(),
5874                          SourceLocation(), SourceLocation(),
5875                          &Context->Idents.get("__va_list_tag"),
5876                          Context->getTrivialTypeSourceInfo(VaListTagType));
5877  QualType VaListTagTypedefType =
5878    Context->getTypedefType(VaListTagTypedefDecl);
5879
5880  // typedef __va_list_tag __builtin_va_list[1];
5881  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
5882  QualType VaListTagArrayType
5883    = Context->getConstantArrayType(VaListTagTypedefType,
5884                                    Size, ArrayType::Normal, 0);
5885  TypeSourceInfo *TInfo
5886    = Context->getTrivialTypeSourceInfo(VaListTagArrayType);
5887  TypedefDecl *VaListTypedefDecl
5888    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5889                          Context->getTranslationUnitDecl(),
5890                          SourceLocation(), SourceLocation(),
5891                          &Context->Idents.get("__builtin_va_list"),
5892                          TInfo);
5893
5894  return VaListTypedefDecl;
5895}
5896
5897static TypedefDecl *
5898CreateX86_64ABIBuiltinVaListDecl(const ASTContext *Context) {
5899  // typedef struct __va_list_tag {
5900  RecordDecl *VaListTagDecl;
5901  VaListTagDecl = CreateRecordDecl(*Context, TTK_Struct,
5902                                   Context->getTranslationUnitDecl(),
5903                                   &Context->Idents.get("__va_list_tag"));
5904  VaListTagDecl->startDefinition();
5905
5906  const size_t NumFields = 4;
5907  QualType FieldTypes[NumFields];
5908  const char *FieldNames[NumFields];
5909
5910  //   unsigned gp_offset;
5911  FieldTypes[0] = Context->UnsignedIntTy;
5912  FieldNames[0] = "gp_offset";
5913
5914  //   unsigned fp_offset;
5915  FieldTypes[1] = Context->UnsignedIntTy;
5916  FieldNames[1] = "fp_offset";
5917
5918  //   void* overflow_arg_area;
5919  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
5920  FieldNames[2] = "overflow_arg_area";
5921
5922  //   void* reg_save_area;
5923  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
5924  FieldNames[3] = "reg_save_area";
5925
5926  // Create fields
5927  for (unsigned i = 0; i < NumFields; ++i) {
5928    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
5929                                         VaListTagDecl,
5930                                         SourceLocation(),
5931                                         SourceLocation(),
5932                                         &Context->Idents.get(FieldNames[i]),
5933                                         FieldTypes[i], /*TInfo=*/0,
5934                                         /*BitWidth=*/0,
5935                                         /*Mutable=*/false,
5936                                         ICIS_NoInit);
5937    Field->setAccess(AS_public);
5938    VaListTagDecl->addDecl(Field);
5939  }
5940  VaListTagDecl->completeDefinition();
5941  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
5942  Context->VaListTagTy = VaListTagType;
5943
5944  // } __va_list_tag;
5945  TypedefDecl *VaListTagTypedefDecl
5946    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5947                          Context->getTranslationUnitDecl(),
5948                          SourceLocation(), SourceLocation(),
5949                          &Context->Idents.get("__va_list_tag"),
5950                          Context->getTrivialTypeSourceInfo(VaListTagType));
5951  QualType VaListTagTypedefType =
5952    Context->getTypedefType(VaListTagTypedefDecl);
5953
5954  // typedef __va_list_tag __builtin_va_list[1];
5955  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
5956  QualType VaListTagArrayType
5957    = Context->getConstantArrayType(VaListTagTypedefType,
5958                                      Size, ArrayType::Normal,0);
5959  TypeSourceInfo *TInfo
5960    = Context->getTrivialTypeSourceInfo(VaListTagArrayType);
5961  TypedefDecl *VaListTypedefDecl
5962    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5963                          Context->getTranslationUnitDecl(),
5964                          SourceLocation(), SourceLocation(),
5965                          &Context->Idents.get("__builtin_va_list"),
5966                          TInfo);
5967
5968  return VaListTypedefDecl;
5969}
5970
5971static TypedefDecl *CreatePNaClABIBuiltinVaListDecl(const ASTContext *Context) {
5972  // typedef int __builtin_va_list[4];
5973  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 4);
5974  QualType IntArrayType
5975    = Context->getConstantArrayType(Context->IntTy,
5976				    Size, ArrayType::Normal, 0);
5977  TypedefDecl *VaListTypedefDecl
5978    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
5979                          Context->getTranslationUnitDecl(),
5980                          SourceLocation(), SourceLocation(),
5981                          &Context->Idents.get("__builtin_va_list"),
5982                          Context->getTrivialTypeSourceInfo(IntArrayType));
5983
5984  return VaListTypedefDecl;
5985}
5986
5987static TypedefDecl *
5988CreateAAPCSABIBuiltinVaListDecl(const ASTContext *Context) {
5989  RecordDecl *VaListDecl;
5990  if (Context->getLangOpts().CPlusPlus) {
5991    // namespace std { struct __va_list {
5992    NamespaceDecl *NS;
5993    NS = NamespaceDecl::Create(const_cast<ASTContext &>(*Context),
5994                               Context->getTranslationUnitDecl(),
5995                               /*Inline*/false, SourceLocation(),
5996                               SourceLocation(), &Context->Idents.get("std"),
5997                               /*PrevDecl*/0);
5998
5999    VaListDecl = CXXRecordDecl::Create(*Context, TTK_Struct,
6000                                       Context->getTranslationUnitDecl(),
6001                                       SourceLocation(), SourceLocation(),
6002                                       &Context->Idents.get("__va_list"));
6003
6004    VaListDecl->setDeclContext(NS);
6005
6006  } else {
6007    // struct __va_list {
6008    VaListDecl = CreateRecordDecl(*Context, TTK_Struct,
6009                                  Context->getTranslationUnitDecl(),
6010                                  &Context->Idents.get("__va_list"));
6011  }
6012
6013  VaListDecl->startDefinition();
6014
6015  // void * __ap;
6016  FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6017                                       VaListDecl,
6018                                       SourceLocation(),
6019                                       SourceLocation(),
6020                                       &Context->Idents.get("__ap"),
6021                                       Context->getPointerType(Context->VoidTy),
6022                                       /*TInfo=*/0,
6023                                       /*BitWidth=*/0,
6024                                       /*Mutable=*/false,
6025                                       ICIS_NoInit);
6026  Field->setAccess(AS_public);
6027  VaListDecl->addDecl(Field);
6028
6029  // };
6030  VaListDecl->completeDefinition();
6031
6032  // typedef struct __va_list __builtin_va_list;
6033  TypeSourceInfo *TInfo
6034    = Context->getTrivialTypeSourceInfo(Context->getRecordType(VaListDecl));
6035
6036  TypedefDecl *VaListTypeDecl
6037    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
6038                          Context->getTranslationUnitDecl(),
6039                          SourceLocation(), SourceLocation(),
6040                          &Context->Idents.get("__builtin_va_list"),
6041                          TInfo);
6042
6043  return VaListTypeDecl;
6044}
6045
6046static TypedefDecl *
6047CreateSystemZBuiltinVaListDecl(const ASTContext *Context) {
6048  // typedef struct __va_list_tag {
6049  RecordDecl *VaListTagDecl;
6050  VaListTagDecl = CreateRecordDecl(*Context, TTK_Struct,
6051                                   Context->getTranslationUnitDecl(),
6052                                   &Context->Idents.get("__va_list_tag"));
6053  VaListTagDecl->startDefinition();
6054
6055  const size_t NumFields = 4;
6056  QualType FieldTypes[NumFields];
6057  const char *FieldNames[NumFields];
6058
6059  //   long __gpr;
6060  FieldTypes[0] = Context->LongTy;
6061  FieldNames[0] = "__gpr";
6062
6063  //   long __fpr;
6064  FieldTypes[1] = Context->LongTy;
6065  FieldNames[1] = "__fpr";
6066
6067  //   void *__overflow_arg_area;
6068  FieldTypes[2] = Context->getPointerType(Context->VoidTy);
6069  FieldNames[2] = "__overflow_arg_area";
6070
6071  //   void *__reg_save_area;
6072  FieldTypes[3] = Context->getPointerType(Context->VoidTy);
6073  FieldNames[3] = "__reg_save_area";
6074
6075  // Create fields
6076  for (unsigned i = 0; i < NumFields; ++i) {
6077    FieldDecl *Field = FieldDecl::Create(const_cast<ASTContext &>(*Context),
6078                                         VaListTagDecl,
6079                                         SourceLocation(),
6080                                         SourceLocation(),
6081                                         &Context->Idents.get(FieldNames[i]),
6082                                         FieldTypes[i], /*TInfo=*/0,
6083                                         /*BitWidth=*/0,
6084                                         /*Mutable=*/false,
6085                                         ICIS_NoInit);
6086    Field->setAccess(AS_public);
6087    VaListTagDecl->addDecl(Field);
6088  }
6089  VaListTagDecl->completeDefinition();
6090  QualType VaListTagType = Context->getRecordType(VaListTagDecl);
6091  Context->VaListTagTy = VaListTagType;
6092
6093  // } __va_list_tag;
6094  TypedefDecl *VaListTagTypedefDecl
6095    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
6096                          Context->getTranslationUnitDecl(),
6097                          SourceLocation(), SourceLocation(),
6098                          &Context->Idents.get("__va_list_tag"),
6099                          Context->getTrivialTypeSourceInfo(VaListTagType));
6100  QualType VaListTagTypedefType =
6101    Context->getTypedefType(VaListTagTypedefDecl);
6102
6103  // typedef __va_list_tag __builtin_va_list[1];
6104  llvm::APInt Size(Context->getTypeSize(Context->getSizeType()), 1);
6105  QualType VaListTagArrayType
6106    = Context->getConstantArrayType(VaListTagTypedefType,
6107                                      Size, ArrayType::Normal,0);
6108  TypeSourceInfo *TInfo
6109    = Context->getTrivialTypeSourceInfo(VaListTagArrayType);
6110  TypedefDecl *VaListTypedefDecl
6111    = TypedefDecl::Create(const_cast<ASTContext &>(*Context),
6112                          Context->getTranslationUnitDecl(),
6113                          SourceLocation(), SourceLocation(),
6114                          &Context->Idents.get("__builtin_va_list"),
6115                          TInfo);
6116
6117  return VaListTypedefDecl;
6118}
6119
6120static TypedefDecl *CreateVaListDecl(const ASTContext *Context,
6121                                     TargetInfo::BuiltinVaListKind Kind) {
6122  switch (Kind) {
6123  case TargetInfo::CharPtrBuiltinVaList:
6124    return CreateCharPtrBuiltinVaListDecl(Context);
6125  case TargetInfo::VoidPtrBuiltinVaList:
6126    return CreateVoidPtrBuiltinVaListDecl(Context);
6127  case TargetInfo::AArch64ABIBuiltinVaList:
6128    return CreateAArch64ABIBuiltinVaListDecl(Context);
6129  case TargetInfo::PowerABIBuiltinVaList:
6130    return CreatePowerABIBuiltinVaListDecl(Context);
6131  case TargetInfo::X86_64ABIBuiltinVaList:
6132    return CreateX86_64ABIBuiltinVaListDecl(Context);
6133  case TargetInfo::PNaClABIBuiltinVaList:
6134    return CreatePNaClABIBuiltinVaListDecl(Context);
6135  case TargetInfo::AAPCSABIBuiltinVaList:
6136    return CreateAAPCSABIBuiltinVaListDecl(Context);
6137  case TargetInfo::SystemZBuiltinVaList:
6138    return CreateSystemZBuiltinVaListDecl(Context);
6139  }
6140
6141  llvm_unreachable("Unhandled __builtin_va_list type kind");
6142}
6143
6144TypedefDecl *ASTContext::getBuiltinVaListDecl() const {
6145  if (!BuiltinVaListDecl)
6146    BuiltinVaListDecl = CreateVaListDecl(this, Target->getBuiltinVaListKind());
6147
6148  return BuiltinVaListDecl;
6149}
6150
6151QualType ASTContext::getVaListTagType() const {
6152  // Force the creation of VaListTagTy by building the __builtin_va_list
6153  // declaration.
6154  if (VaListTagTy.isNull())
6155    (void) getBuiltinVaListDecl();
6156
6157  return VaListTagTy;
6158}
6159
6160void ASTContext::setObjCConstantStringInterface(ObjCInterfaceDecl *Decl) {
6161  assert(ObjCConstantStringType.isNull() &&
6162         "'NSConstantString' type already set!");
6163
6164  ObjCConstantStringType = getObjCInterfaceType(Decl);
6165}
6166
6167/// \brief Retrieve the template name that corresponds to a non-empty
6168/// lookup.
6169TemplateName
6170ASTContext::getOverloadedTemplateName(UnresolvedSetIterator Begin,
6171                                      UnresolvedSetIterator End) const {
6172  unsigned size = End - Begin;
6173  assert(size > 1 && "set is not overloaded!");
6174
6175  void *memory = Allocate(sizeof(OverloadedTemplateStorage) +
6176                          size * sizeof(FunctionTemplateDecl*));
6177  OverloadedTemplateStorage *OT = new(memory) OverloadedTemplateStorage(size);
6178
6179  NamedDecl **Storage = OT->getStorage();
6180  for (UnresolvedSetIterator I = Begin; I != End; ++I) {
6181    NamedDecl *D = *I;
6182    assert(isa<FunctionTemplateDecl>(D) ||
6183           (isa<UsingShadowDecl>(D) &&
6184            isa<FunctionTemplateDecl>(D->getUnderlyingDecl())));
6185    *Storage++ = D;
6186  }
6187
6188  return TemplateName(OT);
6189}
6190
6191/// \brief Retrieve the template name that represents a qualified
6192/// template name such as \c std::vector.
6193TemplateName
6194ASTContext::getQualifiedTemplateName(NestedNameSpecifier *NNS,
6195                                     bool TemplateKeyword,
6196                                     TemplateDecl *Template) const {
6197  assert(NNS && "Missing nested-name-specifier in qualified template name");
6198
6199  // FIXME: Canonicalization?
6200  llvm::FoldingSetNodeID ID;
6201  QualifiedTemplateName::Profile(ID, NNS, TemplateKeyword, Template);
6202
6203  void *InsertPos = 0;
6204  QualifiedTemplateName *QTN =
6205    QualifiedTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6206  if (!QTN) {
6207    QTN = new (*this, llvm::alignOf<QualifiedTemplateName>())
6208        QualifiedTemplateName(NNS, TemplateKeyword, Template);
6209    QualifiedTemplateNames.InsertNode(QTN, InsertPos);
6210  }
6211
6212  return TemplateName(QTN);
6213}
6214
6215/// \brief Retrieve the template name that represents a dependent
6216/// template name such as \c MetaFun::template apply.
6217TemplateName
6218ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
6219                                     const IdentifierInfo *Name) const {
6220  assert((!NNS || NNS->isDependent()) &&
6221         "Nested name specifier must be dependent");
6222
6223  llvm::FoldingSetNodeID ID;
6224  DependentTemplateName::Profile(ID, NNS, Name);
6225
6226  void *InsertPos = 0;
6227  DependentTemplateName *QTN =
6228    DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6229
6230  if (QTN)
6231    return TemplateName(QTN);
6232
6233  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
6234  if (CanonNNS == NNS) {
6235    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6236        DependentTemplateName(NNS, Name);
6237  } else {
6238    TemplateName Canon = getDependentTemplateName(CanonNNS, Name);
6239    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6240        DependentTemplateName(NNS, Name, Canon);
6241    DependentTemplateName *CheckQTN =
6242      DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6243    assert(!CheckQTN && "Dependent type name canonicalization broken");
6244    (void)CheckQTN;
6245  }
6246
6247  DependentTemplateNames.InsertNode(QTN, InsertPos);
6248  return TemplateName(QTN);
6249}
6250
6251/// \brief Retrieve the template name that represents a dependent
6252/// template name such as \c MetaFun::template operator+.
6253TemplateName
6254ASTContext::getDependentTemplateName(NestedNameSpecifier *NNS,
6255                                     OverloadedOperatorKind Operator) const {
6256  assert((!NNS || NNS->isDependent()) &&
6257         "Nested name specifier must be dependent");
6258
6259  llvm::FoldingSetNodeID ID;
6260  DependentTemplateName::Profile(ID, NNS, Operator);
6261
6262  void *InsertPos = 0;
6263  DependentTemplateName *QTN
6264    = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6265
6266  if (QTN)
6267    return TemplateName(QTN);
6268
6269  NestedNameSpecifier *CanonNNS = getCanonicalNestedNameSpecifier(NNS);
6270  if (CanonNNS == NNS) {
6271    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6272        DependentTemplateName(NNS, Operator);
6273  } else {
6274    TemplateName Canon = getDependentTemplateName(CanonNNS, Operator);
6275    QTN = new (*this, llvm::alignOf<DependentTemplateName>())
6276        DependentTemplateName(NNS, Operator, Canon);
6277
6278    DependentTemplateName *CheckQTN
6279      = DependentTemplateNames.FindNodeOrInsertPos(ID, InsertPos);
6280    assert(!CheckQTN && "Dependent template name canonicalization broken");
6281    (void)CheckQTN;
6282  }
6283
6284  DependentTemplateNames.InsertNode(QTN, InsertPos);
6285  return TemplateName(QTN);
6286}
6287
6288TemplateName
6289ASTContext::getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
6290                                         TemplateName replacement) const {
6291  llvm::FoldingSetNodeID ID;
6292  SubstTemplateTemplateParmStorage::Profile(ID, param, replacement);
6293
6294  void *insertPos = 0;
6295  SubstTemplateTemplateParmStorage *subst
6296    = SubstTemplateTemplateParms.FindNodeOrInsertPos(ID, insertPos);
6297
6298  if (!subst) {
6299    subst = new (*this) SubstTemplateTemplateParmStorage(param, replacement);
6300    SubstTemplateTemplateParms.InsertNode(subst, insertPos);
6301  }
6302
6303  return TemplateName(subst);
6304}
6305
6306TemplateName
6307ASTContext::getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
6308                                       const TemplateArgument &ArgPack) const {
6309  ASTContext &Self = const_cast<ASTContext &>(*this);
6310  llvm::FoldingSetNodeID ID;
6311  SubstTemplateTemplateParmPackStorage::Profile(ID, Self, Param, ArgPack);
6312
6313  void *InsertPos = 0;
6314  SubstTemplateTemplateParmPackStorage *Subst
6315    = SubstTemplateTemplateParmPacks.FindNodeOrInsertPos(ID, InsertPos);
6316
6317  if (!Subst) {
6318    Subst = new (*this) SubstTemplateTemplateParmPackStorage(Param,
6319                                                           ArgPack.pack_size(),
6320                                                         ArgPack.pack_begin());
6321    SubstTemplateTemplateParmPacks.InsertNode(Subst, InsertPos);
6322  }
6323
6324  return TemplateName(Subst);
6325}
6326
6327/// getFromTargetType - Given one of the integer types provided by
6328/// TargetInfo, produce the corresponding type. The unsigned @p Type
6329/// is actually a value of type @c TargetInfo::IntType.
6330CanQualType ASTContext::getFromTargetType(unsigned Type) const {
6331  switch (Type) {
6332  case TargetInfo::NoInt: return CanQualType();
6333  case TargetInfo::SignedShort: return ShortTy;
6334  case TargetInfo::UnsignedShort: return UnsignedShortTy;
6335  case TargetInfo::SignedInt: return IntTy;
6336  case TargetInfo::UnsignedInt: return UnsignedIntTy;
6337  case TargetInfo::SignedLong: return LongTy;
6338  case TargetInfo::UnsignedLong: return UnsignedLongTy;
6339  case TargetInfo::SignedLongLong: return LongLongTy;
6340  case TargetInfo::UnsignedLongLong: return UnsignedLongLongTy;
6341  }
6342
6343  llvm_unreachable("Unhandled TargetInfo::IntType value");
6344}
6345
6346//===----------------------------------------------------------------------===//
6347//                        Type Predicates.
6348//===----------------------------------------------------------------------===//
6349
6350/// getObjCGCAttr - Returns one of GCNone, Weak or Strong objc's
6351/// garbage collection attribute.
6352///
6353Qualifiers::GC ASTContext::getObjCGCAttrKind(QualType Ty) const {
6354  if (getLangOpts().getGC() == LangOptions::NonGC)
6355    return Qualifiers::GCNone;
6356
6357  assert(getLangOpts().ObjC1);
6358  Qualifiers::GC GCAttrs = Ty.getObjCGCAttr();
6359
6360  // Default behaviour under objective-C's gc is for ObjC pointers
6361  // (or pointers to them) be treated as though they were declared
6362  // as __strong.
6363  if (GCAttrs == Qualifiers::GCNone) {
6364    if (Ty->isObjCObjectPointerType() || Ty->isBlockPointerType())
6365      return Qualifiers::Strong;
6366    else if (Ty->isPointerType())
6367      return getObjCGCAttrKind(Ty->getAs<PointerType>()->getPointeeType());
6368  } else {
6369    // It's not valid to set GC attributes on anything that isn't a
6370    // pointer.
6371#ifndef NDEBUG
6372    QualType CT = Ty->getCanonicalTypeInternal();
6373    while (const ArrayType *AT = dyn_cast<ArrayType>(CT))
6374      CT = AT->getElementType();
6375    assert(CT->isAnyPointerType() || CT->isBlockPointerType());
6376#endif
6377  }
6378  return GCAttrs;
6379}
6380
6381//===----------------------------------------------------------------------===//
6382//                        Type Compatibility Testing
6383//===----------------------------------------------------------------------===//
6384
6385/// areCompatVectorTypes - Return true if the two specified vector types are
6386/// compatible.
6387static bool areCompatVectorTypes(const VectorType *LHS,
6388                                 const VectorType *RHS) {
6389  assert(LHS->isCanonicalUnqualified() && RHS->isCanonicalUnqualified());
6390  return LHS->getElementType() == RHS->getElementType() &&
6391         LHS->getNumElements() == RHS->getNumElements();
6392}
6393
6394bool ASTContext::areCompatibleVectorTypes(QualType FirstVec,
6395                                          QualType SecondVec) {
6396  assert(FirstVec->isVectorType() && "FirstVec should be a vector type");
6397  assert(SecondVec->isVectorType() && "SecondVec should be a vector type");
6398
6399  if (hasSameUnqualifiedType(FirstVec, SecondVec))
6400    return true;
6401
6402  // Treat Neon vector types and most AltiVec vector types as if they are the
6403  // equivalent GCC vector types.
6404  const VectorType *First = FirstVec->getAs<VectorType>();
6405  const VectorType *Second = SecondVec->getAs<VectorType>();
6406  if (First->getNumElements() == Second->getNumElements() &&
6407      hasSameType(First->getElementType(), Second->getElementType()) &&
6408      First->getVectorKind() != VectorType::AltiVecPixel &&
6409      First->getVectorKind() != VectorType::AltiVecBool &&
6410      Second->getVectorKind() != VectorType::AltiVecPixel &&
6411      Second->getVectorKind() != VectorType::AltiVecBool)
6412    return true;
6413
6414  return false;
6415}
6416
6417//===----------------------------------------------------------------------===//
6418// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
6419//===----------------------------------------------------------------------===//
6420
6421/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
6422/// inheritance hierarchy of 'rProto'.
6423bool
6424ASTContext::ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
6425                                           ObjCProtocolDecl *rProto) const {
6426  if (declaresSameEntity(lProto, rProto))
6427    return true;
6428  for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
6429       E = rProto->protocol_end(); PI != E; ++PI)
6430    if (ProtocolCompatibleWithProtocol(lProto, *PI))
6431      return true;
6432  return false;
6433}
6434
6435/// ObjCQualifiedClassTypesAreCompatible - compare  Class<pr,...> and
6436/// Class<pr1, ...>.
6437bool ASTContext::ObjCQualifiedClassTypesAreCompatible(QualType lhs,
6438                                                      QualType rhs) {
6439  const ObjCObjectPointerType *lhsQID = lhs->getAs<ObjCObjectPointerType>();
6440  const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
6441  assert ((lhsQID && rhsOPT) && "ObjCQualifiedClassTypesAreCompatible");
6442
6443  for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
6444       E = lhsQID->qual_end(); I != E; ++I) {
6445    bool match = false;
6446    ObjCProtocolDecl *lhsProto = *I;
6447    for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
6448         E = rhsOPT->qual_end(); J != E; ++J) {
6449      ObjCProtocolDecl *rhsProto = *J;
6450      if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto)) {
6451        match = true;
6452        break;
6453      }
6454    }
6455    if (!match)
6456      return false;
6457  }
6458  return true;
6459}
6460
6461/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
6462/// ObjCQualifiedIDType.
6463bool ASTContext::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
6464                                                   bool compare) {
6465  // Allow id<P..> and an 'id' or void* type in all cases.
6466  if (lhs->isVoidPointerType() ||
6467      lhs->isObjCIdType() || lhs->isObjCClassType())
6468    return true;
6469  else if (rhs->isVoidPointerType() ||
6470           rhs->isObjCIdType() || rhs->isObjCClassType())
6471    return true;
6472
6473  if (const ObjCObjectPointerType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
6474    const ObjCObjectPointerType *rhsOPT = rhs->getAs<ObjCObjectPointerType>();
6475
6476    if (!rhsOPT) return false;
6477
6478    if (rhsOPT->qual_empty()) {
6479      // If the RHS is a unqualified interface pointer "NSString*",
6480      // make sure we check the class hierarchy.
6481      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
6482        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
6483             E = lhsQID->qual_end(); I != E; ++I) {
6484          // when comparing an id<P> on lhs with a static type on rhs,
6485          // see if static class implements all of id's protocols, directly or
6486          // through its super class and categories.
6487          if (!rhsID->ClassImplementsProtocol(*I, true))
6488            return false;
6489        }
6490      }
6491      // If there are no qualifiers and no interface, we have an 'id'.
6492      return true;
6493    }
6494    // Both the right and left sides have qualifiers.
6495    for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
6496         E = lhsQID->qual_end(); I != E; ++I) {
6497      ObjCProtocolDecl *lhsProto = *I;
6498      bool match = false;
6499
6500      // when comparing an id<P> on lhs with a static type on rhs,
6501      // see if static class implements all of id's protocols, directly or
6502      // through its super class and categories.
6503      for (ObjCObjectPointerType::qual_iterator J = rhsOPT->qual_begin(),
6504           E = rhsOPT->qual_end(); J != E; ++J) {
6505        ObjCProtocolDecl *rhsProto = *J;
6506        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6507            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6508          match = true;
6509          break;
6510        }
6511      }
6512      // If the RHS is a qualified interface pointer "NSString<P>*",
6513      // make sure we check the class hierarchy.
6514      if (ObjCInterfaceDecl *rhsID = rhsOPT->getInterfaceDecl()) {
6515        for (ObjCObjectPointerType::qual_iterator I = lhsQID->qual_begin(),
6516             E = lhsQID->qual_end(); I != E; ++I) {
6517          // when comparing an id<P> on lhs with a static type on rhs,
6518          // see if static class implements all of id's protocols, directly or
6519          // through its super class and categories.
6520          if (rhsID->ClassImplementsProtocol(*I, true)) {
6521            match = true;
6522            break;
6523          }
6524        }
6525      }
6526      if (!match)
6527        return false;
6528    }
6529
6530    return true;
6531  }
6532
6533  const ObjCObjectPointerType *rhsQID = rhs->getAsObjCQualifiedIdType();
6534  assert(rhsQID && "One of the LHS/RHS should be id<x>");
6535
6536  if (const ObjCObjectPointerType *lhsOPT =
6537        lhs->getAsObjCInterfacePointerType()) {
6538    // If both the right and left sides have qualifiers.
6539    for (ObjCObjectPointerType::qual_iterator I = lhsOPT->qual_begin(),
6540         E = lhsOPT->qual_end(); I != E; ++I) {
6541      ObjCProtocolDecl *lhsProto = *I;
6542      bool match = false;
6543
6544      // when comparing an id<P> on rhs with a static type on lhs,
6545      // see if static class implements all of id's protocols, directly or
6546      // through its super class and categories.
6547      // First, lhs protocols in the qualifier list must be found, direct
6548      // or indirect in rhs's qualifier list or it is a mismatch.
6549      for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
6550           E = rhsQID->qual_end(); J != E; ++J) {
6551        ObjCProtocolDecl *rhsProto = *J;
6552        if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6553            (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6554          match = true;
6555          break;
6556        }
6557      }
6558      if (!match)
6559        return false;
6560    }
6561
6562    // Static class's protocols, or its super class or category protocols
6563    // must be found, direct or indirect in rhs's qualifier list or it is a mismatch.
6564    if (ObjCInterfaceDecl *lhsID = lhsOPT->getInterfaceDecl()) {
6565      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
6566      CollectInheritedProtocols(lhsID, LHSInheritedProtocols);
6567      // This is rather dubious but matches gcc's behavior. If lhs has
6568      // no type qualifier and its class has no static protocol(s)
6569      // assume that it is mismatch.
6570      if (LHSInheritedProtocols.empty() && lhsOPT->qual_empty())
6571        return false;
6572      for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
6573           LHSInheritedProtocols.begin(),
6574           E = LHSInheritedProtocols.end(); I != E; ++I) {
6575        bool match = false;
6576        ObjCProtocolDecl *lhsProto = (*I);
6577        for (ObjCObjectPointerType::qual_iterator J = rhsQID->qual_begin(),
6578             E = rhsQID->qual_end(); J != E; ++J) {
6579          ObjCProtocolDecl *rhsProto = *J;
6580          if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
6581              (compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
6582            match = true;
6583            break;
6584          }
6585        }
6586        if (!match)
6587          return false;
6588      }
6589    }
6590    return true;
6591  }
6592  return false;
6593}
6594
6595/// canAssignObjCInterfaces - Return true if the two interface types are
6596/// compatible for assignment from RHS to LHS.  This handles validation of any
6597/// protocol qualifiers on the LHS or RHS.
6598///
6599bool ASTContext::canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
6600                                         const ObjCObjectPointerType *RHSOPT) {
6601  const ObjCObjectType* LHS = LHSOPT->getObjectType();
6602  const ObjCObjectType* RHS = RHSOPT->getObjectType();
6603
6604  // If either type represents the built-in 'id' or 'Class' types, return true.
6605  if (LHS->isObjCUnqualifiedIdOrClass() ||
6606      RHS->isObjCUnqualifiedIdOrClass())
6607    return true;
6608
6609  if (LHS->isObjCQualifiedId() || RHS->isObjCQualifiedId())
6610    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
6611                                             QualType(RHSOPT,0),
6612                                             false);
6613
6614  if (LHS->isObjCQualifiedClass() && RHS->isObjCQualifiedClass())
6615    return ObjCQualifiedClassTypesAreCompatible(QualType(LHSOPT,0),
6616                                                QualType(RHSOPT,0));
6617
6618  // If we have 2 user-defined types, fall into that path.
6619  if (LHS->getInterface() && RHS->getInterface())
6620    return canAssignObjCInterfaces(LHS, RHS);
6621
6622  return false;
6623}
6624
6625/// canAssignObjCInterfacesInBlockPointer - This routine is specifically written
6626/// for providing type-safety for objective-c pointers used to pass/return
6627/// arguments in block literals. When passed as arguments, passing 'A*' where
6628/// 'id' is expected is not OK. Passing 'Sub *" where 'Super *" is expected is
6629/// not OK. For the return type, the opposite is not OK.
6630bool ASTContext::canAssignObjCInterfacesInBlockPointer(
6631                                         const ObjCObjectPointerType *LHSOPT,
6632                                         const ObjCObjectPointerType *RHSOPT,
6633                                         bool BlockReturnType) {
6634  if (RHSOPT->isObjCBuiltinType() || LHSOPT->isObjCIdType())
6635    return true;
6636
6637  if (LHSOPT->isObjCBuiltinType()) {
6638    return RHSOPT->isObjCBuiltinType() || RHSOPT->isObjCQualifiedIdType();
6639  }
6640
6641  if (LHSOPT->isObjCQualifiedIdType() || RHSOPT->isObjCQualifiedIdType())
6642    return ObjCQualifiedIdTypesAreCompatible(QualType(LHSOPT,0),
6643                                             QualType(RHSOPT,0),
6644                                             false);
6645
6646  const ObjCInterfaceType* LHS = LHSOPT->getInterfaceType();
6647  const ObjCInterfaceType* RHS = RHSOPT->getInterfaceType();
6648  if (LHS && RHS)  { // We have 2 user-defined types.
6649    if (LHS != RHS) {
6650      if (LHS->getDecl()->isSuperClassOf(RHS->getDecl()))
6651        return BlockReturnType;
6652      if (RHS->getDecl()->isSuperClassOf(LHS->getDecl()))
6653        return !BlockReturnType;
6654    }
6655    else
6656      return true;
6657  }
6658  return false;
6659}
6660
6661/// getIntersectionOfProtocols - This routine finds the intersection of set
6662/// of protocols inherited from two distinct objective-c pointer objects.
6663/// It is used to build composite qualifier list of the composite type of
6664/// the conditional expression involving two objective-c pointer objects.
6665static
6666void getIntersectionOfProtocols(ASTContext &Context,
6667                                const ObjCObjectPointerType *LHSOPT,
6668                                const ObjCObjectPointerType *RHSOPT,
6669      SmallVectorImpl<ObjCProtocolDecl *> &IntersectionOfProtocols) {
6670
6671  const ObjCObjectType* LHS = LHSOPT->getObjectType();
6672  const ObjCObjectType* RHS = RHSOPT->getObjectType();
6673  assert(LHS->getInterface() && "LHS must have an interface base");
6674  assert(RHS->getInterface() && "RHS must have an interface base");
6675
6676  llvm::SmallPtrSet<ObjCProtocolDecl *, 8> InheritedProtocolSet;
6677  unsigned LHSNumProtocols = LHS->getNumProtocols();
6678  if (LHSNumProtocols > 0)
6679    InheritedProtocolSet.insert(LHS->qual_begin(), LHS->qual_end());
6680  else {
6681    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> LHSInheritedProtocols;
6682    Context.CollectInheritedProtocols(LHS->getInterface(),
6683                                      LHSInheritedProtocols);
6684    InheritedProtocolSet.insert(LHSInheritedProtocols.begin(),
6685                                LHSInheritedProtocols.end());
6686  }
6687
6688  unsigned RHSNumProtocols = RHS->getNumProtocols();
6689  if (RHSNumProtocols > 0) {
6690    ObjCProtocolDecl **RHSProtocols =
6691      const_cast<ObjCProtocolDecl **>(RHS->qual_begin());
6692    for (unsigned i = 0; i < RHSNumProtocols; ++i)
6693      if (InheritedProtocolSet.count(RHSProtocols[i]))
6694        IntersectionOfProtocols.push_back(RHSProtocols[i]);
6695  } else {
6696    llvm::SmallPtrSet<ObjCProtocolDecl *, 8> RHSInheritedProtocols;
6697    Context.CollectInheritedProtocols(RHS->getInterface(),
6698                                      RHSInheritedProtocols);
6699    for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
6700         RHSInheritedProtocols.begin(),
6701         E = RHSInheritedProtocols.end(); I != E; ++I)
6702      if (InheritedProtocolSet.count((*I)))
6703        IntersectionOfProtocols.push_back((*I));
6704  }
6705}
6706
6707/// areCommonBaseCompatible - Returns common base class of the two classes if
6708/// one found. Note that this is O'2 algorithm. But it will be called as the
6709/// last type comparison in a ?-exp of ObjC pointer types before a
6710/// warning is issued. So, its invokation is extremely rare.
6711QualType ASTContext::areCommonBaseCompatible(
6712                                          const ObjCObjectPointerType *Lptr,
6713                                          const ObjCObjectPointerType *Rptr) {
6714  const ObjCObjectType *LHS = Lptr->getObjectType();
6715  const ObjCObjectType *RHS = Rptr->getObjectType();
6716  const ObjCInterfaceDecl* LDecl = LHS->getInterface();
6717  const ObjCInterfaceDecl* RDecl = RHS->getInterface();
6718  if (!LDecl || !RDecl || (declaresSameEntity(LDecl, RDecl)))
6719    return QualType();
6720
6721  do {
6722    LHS = cast<ObjCInterfaceType>(getObjCInterfaceType(LDecl));
6723    if (canAssignObjCInterfaces(LHS, RHS)) {
6724      SmallVector<ObjCProtocolDecl *, 8> Protocols;
6725      getIntersectionOfProtocols(*this, Lptr, Rptr, Protocols);
6726
6727      QualType Result = QualType(LHS, 0);
6728      if (!Protocols.empty())
6729        Result = getObjCObjectType(Result, Protocols.data(), Protocols.size());
6730      Result = getObjCObjectPointerType(Result);
6731      return Result;
6732    }
6733  } while ((LDecl = LDecl->getSuperClass()));
6734
6735  return QualType();
6736}
6737
6738bool ASTContext::canAssignObjCInterfaces(const ObjCObjectType *LHS,
6739                                         const ObjCObjectType *RHS) {
6740  assert(LHS->getInterface() && "LHS is not an interface type");
6741  assert(RHS->getInterface() && "RHS is not an interface type");
6742
6743  // Verify that the base decls are compatible: the RHS must be a subclass of
6744  // the LHS.
6745  if (!LHS->getInterface()->isSuperClassOf(RHS->getInterface()))
6746    return false;
6747
6748  // RHS must have a superset of the protocols in the LHS.  If the LHS is not
6749  // protocol qualified at all, then we are good.
6750  if (LHS->getNumProtocols() == 0)
6751    return true;
6752
6753  // Okay, we know the LHS has protocol qualifiers.  If the RHS doesn't,
6754  // more detailed analysis is required.
6755  if (RHS->getNumProtocols() == 0) {
6756    // OK, if LHS is a superclass of RHS *and*
6757    // this superclass is assignment compatible with LHS.
6758    // false otherwise.
6759    bool IsSuperClass =
6760      LHS->getInterface()->isSuperClassOf(RHS->getInterface());
6761    if (IsSuperClass) {
6762      // OK if conversion of LHS to SuperClass results in narrowing of types
6763      // ; i.e., SuperClass may implement at least one of the protocols
6764      // in LHS's protocol list. Example, SuperObj<P1> = lhs<P1,P2> is ok.
6765      // But not SuperObj<P1,P2,P3> = lhs<P1,P2>.
6766      llvm::SmallPtrSet<ObjCProtocolDecl *, 8> SuperClassInheritedProtocols;
6767      CollectInheritedProtocols(RHS->getInterface(), SuperClassInheritedProtocols);
6768      // If super class has no protocols, it is not a match.
6769      if (SuperClassInheritedProtocols.empty())
6770        return false;
6771
6772      for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
6773           LHSPE = LHS->qual_end();
6774           LHSPI != LHSPE; LHSPI++) {
6775        bool SuperImplementsProtocol = false;
6776        ObjCProtocolDecl *LHSProto = (*LHSPI);
6777
6778        for (llvm::SmallPtrSet<ObjCProtocolDecl*,8>::iterator I =
6779             SuperClassInheritedProtocols.begin(),
6780             E = SuperClassInheritedProtocols.end(); I != E; ++I) {
6781          ObjCProtocolDecl *SuperClassProto = (*I);
6782          if (SuperClassProto->lookupProtocolNamed(LHSProto->getIdentifier())) {
6783            SuperImplementsProtocol = true;
6784            break;
6785          }
6786        }
6787        if (!SuperImplementsProtocol)
6788          return false;
6789      }
6790      return true;
6791    }
6792    return false;
6793  }
6794
6795  for (ObjCObjectType::qual_iterator LHSPI = LHS->qual_begin(),
6796                                     LHSPE = LHS->qual_end();
6797       LHSPI != LHSPE; LHSPI++) {
6798    bool RHSImplementsProtocol = false;
6799
6800    // If the RHS doesn't implement the protocol on the left, the types
6801    // are incompatible.
6802    for (ObjCObjectType::qual_iterator RHSPI = RHS->qual_begin(),
6803                                       RHSPE = RHS->qual_end();
6804         RHSPI != RHSPE; RHSPI++) {
6805      if ((*RHSPI)->lookupProtocolNamed((*LHSPI)->getIdentifier())) {
6806        RHSImplementsProtocol = true;
6807        break;
6808      }
6809    }
6810    // FIXME: For better diagnostics, consider passing back the protocol name.
6811    if (!RHSImplementsProtocol)
6812      return false;
6813  }
6814  // The RHS implements all protocols listed on the LHS.
6815  return true;
6816}
6817
6818bool ASTContext::areComparableObjCPointerTypes(QualType LHS, QualType RHS) {
6819  // get the "pointed to" types
6820  const ObjCObjectPointerType *LHSOPT = LHS->getAs<ObjCObjectPointerType>();
6821  const ObjCObjectPointerType *RHSOPT = RHS->getAs<ObjCObjectPointerType>();
6822
6823  if (!LHSOPT || !RHSOPT)
6824    return false;
6825
6826  return canAssignObjCInterfaces(LHSOPT, RHSOPT) ||
6827         canAssignObjCInterfaces(RHSOPT, LHSOPT);
6828}
6829
6830bool ASTContext::canBindObjCObjectType(QualType To, QualType From) {
6831  return canAssignObjCInterfaces(
6832                getObjCObjectPointerType(To)->getAs<ObjCObjectPointerType>(),
6833                getObjCObjectPointerType(From)->getAs<ObjCObjectPointerType>());
6834}
6835
6836/// typesAreCompatible - C99 6.7.3p9: For two qualified types to be compatible,
6837/// both shall have the identically qualified version of a compatible type.
6838/// C99 6.2.7p1: Two types have compatible types if their types are the
6839/// same. See 6.7.[2,3,5] for additional rules.
6840bool ASTContext::typesAreCompatible(QualType LHS, QualType RHS,
6841                                    bool CompareUnqualified) {
6842  if (getLangOpts().CPlusPlus)
6843    return hasSameType(LHS, RHS);
6844
6845  return !mergeTypes(LHS, RHS, false, CompareUnqualified).isNull();
6846}
6847
6848bool ASTContext::propertyTypesAreCompatible(QualType LHS, QualType RHS) {
6849  return typesAreCompatible(LHS, RHS);
6850}
6851
6852bool ASTContext::typesAreBlockPointerCompatible(QualType LHS, QualType RHS) {
6853  return !mergeTypes(LHS, RHS, true).isNull();
6854}
6855
6856/// mergeTransparentUnionType - if T is a transparent union type and a member
6857/// of T is compatible with SubType, return the merged type, else return
6858/// QualType()
6859QualType ASTContext::mergeTransparentUnionType(QualType T, QualType SubType,
6860                                               bool OfBlockPointer,
6861                                               bool Unqualified) {
6862  if (const RecordType *UT = T->getAsUnionType()) {
6863    RecordDecl *UD = UT->getDecl();
6864    if (UD->hasAttr<TransparentUnionAttr>()) {
6865      for (RecordDecl::field_iterator it = UD->field_begin(),
6866           itend = UD->field_end(); it != itend; ++it) {
6867        QualType ET = it->getType().getUnqualifiedType();
6868        QualType MT = mergeTypes(ET, SubType, OfBlockPointer, Unqualified);
6869        if (!MT.isNull())
6870          return MT;
6871      }
6872    }
6873  }
6874
6875  return QualType();
6876}
6877
6878/// mergeFunctionArgumentTypes - merge two types which appear as function
6879/// argument types
6880QualType ASTContext::mergeFunctionArgumentTypes(QualType lhs, QualType rhs,
6881                                                bool OfBlockPointer,
6882                                                bool Unqualified) {
6883  // GNU extension: two types are compatible if they appear as a function
6884  // argument, one of the types is a transparent union type and the other
6885  // type is compatible with a union member
6886  QualType lmerge = mergeTransparentUnionType(lhs, rhs, OfBlockPointer,
6887                                              Unqualified);
6888  if (!lmerge.isNull())
6889    return lmerge;
6890
6891  QualType rmerge = mergeTransparentUnionType(rhs, lhs, OfBlockPointer,
6892                                              Unqualified);
6893  if (!rmerge.isNull())
6894    return rmerge;
6895
6896  return mergeTypes(lhs, rhs, OfBlockPointer, Unqualified);
6897}
6898
6899QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
6900                                        bool OfBlockPointer,
6901                                        bool Unqualified) {
6902  const FunctionType *lbase = lhs->getAs<FunctionType>();
6903  const FunctionType *rbase = rhs->getAs<FunctionType>();
6904  const FunctionProtoType *lproto = dyn_cast<FunctionProtoType>(lbase);
6905  const FunctionProtoType *rproto = dyn_cast<FunctionProtoType>(rbase);
6906  bool allLTypes = true;
6907  bool allRTypes = true;
6908
6909  // Check return type
6910  QualType retType;
6911  if (OfBlockPointer) {
6912    QualType RHS = rbase->getResultType();
6913    QualType LHS = lbase->getResultType();
6914    bool UnqualifiedResult = Unqualified;
6915    if (!UnqualifiedResult)
6916      UnqualifiedResult = (!RHS.hasQualifiers() && LHS.hasQualifiers());
6917    retType = mergeTypes(LHS, RHS, true, UnqualifiedResult, true);
6918  }
6919  else
6920    retType = mergeTypes(lbase->getResultType(), rbase->getResultType(), false,
6921                         Unqualified);
6922  if (retType.isNull()) return QualType();
6923
6924  if (Unqualified)
6925    retType = retType.getUnqualifiedType();
6926
6927  CanQualType LRetType = getCanonicalType(lbase->getResultType());
6928  CanQualType RRetType = getCanonicalType(rbase->getResultType());
6929  if (Unqualified) {
6930    LRetType = LRetType.getUnqualifiedType();
6931    RRetType = RRetType.getUnqualifiedType();
6932  }
6933
6934  if (getCanonicalType(retType) != LRetType)
6935    allLTypes = false;
6936  if (getCanonicalType(retType) != RRetType)
6937    allRTypes = false;
6938
6939  // FIXME: double check this
6940  // FIXME: should we error if lbase->getRegParmAttr() != 0 &&
6941  //                           rbase->getRegParmAttr() != 0 &&
6942  //                           lbase->getRegParmAttr() != rbase->getRegParmAttr()?
6943  FunctionType::ExtInfo lbaseInfo = lbase->getExtInfo();
6944  FunctionType::ExtInfo rbaseInfo = rbase->getExtInfo();
6945
6946  // Compatible functions must have compatible calling conventions
6947  if (!isSameCallConv(lbaseInfo.getCC(), rbaseInfo.getCC()))
6948    return QualType();
6949
6950  // Regparm is part of the calling convention.
6951  if (lbaseInfo.getHasRegParm() != rbaseInfo.getHasRegParm())
6952    return QualType();
6953  if (lbaseInfo.getRegParm() != rbaseInfo.getRegParm())
6954    return QualType();
6955
6956  if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
6957    return QualType();
6958
6959  // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
6960  bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
6961
6962  if (lbaseInfo.getNoReturn() != NoReturn)
6963    allLTypes = false;
6964  if (rbaseInfo.getNoReturn() != NoReturn)
6965    allRTypes = false;
6966
6967  FunctionType::ExtInfo einfo = lbaseInfo.withNoReturn(NoReturn);
6968
6969  if (lproto && rproto) { // two C99 style function prototypes
6970    assert(!lproto->hasExceptionSpec() && !rproto->hasExceptionSpec() &&
6971           "C++ shouldn't be here");
6972    unsigned lproto_nargs = lproto->getNumArgs();
6973    unsigned rproto_nargs = rproto->getNumArgs();
6974
6975    // Compatible functions must have the same number of arguments
6976    if (lproto_nargs != rproto_nargs)
6977      return QualType();
6978
6979    // Variadic and non-variadic functions aren't compatible
6980    if (lproto->isVariadic() != rproto->isVariadic())
6981      return QualType();
6982
6983    if (lproto->getTypeQuals() != rproto->getTypeQuals())
6984      return QualType();
6985
6986    if (LangOpts.ObjCAutoRefCount &&
6987        !FunctionTypesMatchOnNSConsumedAttrs(rproto, lproto))
6988      return QualType();
6989
6990    // Check argument compatibility
6991    SmallVector<QualType, 10> types;
6992    for (unsigned i = 0; i < lproto_nargs; i++) {
6993      QualType largtype = lproto->getArgType(i).getUnqualifiedType();
6994      QualType rargtype = rproto->getArgType(i).getUnqualifiedType();
6995      QualType argtype = mergeFunctionArgumentTypes(largtype, rargtype,
6996                                                    OfBlockPointer,
6997                                                    Unqualified);
6998      if (argtype.isNull()) return QualType();
6999
7000      if (Unqualified)
7001        argtype = argtype.getUnqualifiedType();
7002
7003      types.push_back(argtype);
7004      if (Unqualified) {
7005        largtype = largtype.getUnqualifiedType();
7006        rargtype = rargtype.getUnqualifiedType();
7007      }
7008
7009      if (getCanonicalType(argtype) != getCanonicalType(largtype))
7010        allLTypes = false;
7011      if (getCanonicalType(argtype) != getCanonicalType(rargtype))
7012        allRTypes = false;
7013    }
7014
7015    if (allLTypes) return lhs;
7016    if (allRTypes) return rhs;
7017
7018    FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
7019    EPI.ExtInfo = einfo;
7020    return getFunctionType(retType, types, EPI);
7021  }
7022
7023  if (lproto) allRTypes = false;
7024  if (rproto) allLTypes = false;
7025
7026  const FunctionProtoType *proto = lproto ? lproto : rproto;
7027  if (proto) {
7028    assert(!proto->hasExceptionSpec() && "C++ shouldn't be here");
7029    if (proto->isVariadic()) return QualType();
7030    // Check that the types are compatible with the types that
7031    // would result from default argument promotions (C99 6.7.5.3p15).
7032    // The only types actually affected are promotable integer
7033    // types and floats, which would be passed as a different
7034    // type depending on whether the prototype is visible.
7035    unsigned proto_nargs = proto->getNumArgs();
7036    for (unsigned i = 0; i < proto_nargs; ++i) {
7037      QualType argTy = proto->getArgType(i);
7038
7039      // Look at the converted type of enum types, since that is the type used
7040      // to pass enum values.
7041      if (const EnumType *Enum = argTy->getAs<EnumType>()) {
7042        argTy = Enum->getDecl()->getIntegerType();
7043        if (argTy.isNull())
7044          return QualType();
7045      }
7046
7047      if (argTy->isPromotableIntegerType() ||
7048          getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
7049        return QualType();
7050    }
7051
7052    if (allLTypes) return lhs;
7053    if (allRTypes) return rhs;
7054
7055    FunctionProtoType::ExtProtoInfo EPI = proto->getExtProtoInfo();
7056    EPI.ExtInfo = einfo;
7057    return getFunctionType(retType, proto->getArgTypes(), EPI);
7058  }
7059
7060  if (allLTypes) return lhs;
7061  if (allRTypes) return rhs;
7062  return getFunctionNoProtoType(retType, einfo);
7063}
7064
7065/// Given that we have an enum type and a non-enum type, try to merge them.
7066static QualType mergeEnumWithInteger(ASTContext &Context, const EnumType *ET,
7067                                     QualType other, bool isBlockReturnType) {
7068  // C99 6.7.2.2p4: Each enumerated type shall be compatible with char,
7069  // a signed integer type, or an unsigned integer type.
7070  // Compatibility is based on the underlying type, not the promotion
7071  // type.
7072  QualType underlyingType = ET->getDecl()->getIntegerType();
7073  if (underlyingType.isNull()) return QualType();
7074  if (Context.hasSameType(underlyingType, other))
7075    return other;
7076
7077  // In block return types, we're more permissive and accept any
7078  // integral type of the same size.
7079  if (isBlockReturnType && other->isIntegerType() &&
7080      Context.getTypeSize(underlyingType) == Context.getTypeSize(other))
7081    return other;
7082
7083  return QualType();
7084}
7085
7086QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
7087                                bool OfBlockPointer,
7088                                bool Unqualified, bool BlockReturnType) {
7089  // C++ [expr]: If an expression initially has the type "reference to T", the
7090  // type is adjusted to "T" prior to any further analysis, the expression
7091  // designates the object or function denoted by the reference, and the
7092  // expression is an lvalue unless the reference is an rvalue reference and
7093  // the expression is a function call (possibly inside parentheses).
7094  assert(!LHS->getAs<ReferenceType>() && "LHS is a reference type?");
7095  assert(!RHS->getAs<ReferenceType>() && "RHS is a reference type?");
7096
7097  if (Unqualified) {
7098    LHS = LHS.getUnqualifiedType();
7099    RHS = RHS.getUnqualifiedType();
7100  }
7101
7102  QualType LHSCan = getCanonicalType(LHS),
7103           RHSCan = getCanonicalType(RHS);
7104
7105  // If two types are identical, they are compatible.
7106  if (LHSCan == RHSCan)
7107    return LHS;
7108
7109  // If the qualifiers are different, the types aren't compatible... mostly.
7110  Qualifiers LQuals = LHSCan.getLocalQualifiers();
7111  Qualifiers RQuals = RHSCan.getLocalQualifiers();
7112  if (LQuals != RQuals) {
7113    // If any of these qualifiers are different, we have a type
7114    // mismatch.
7115    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
7116        LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
7117        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
7118      return QualType();
7119
7120    // Exactly one GC qualifier difference is allowed: __strong is
7121    // okay if the other type has no GC qualifier but is an Objective
7122    // C object pointer (i.e. implicitly strong by default).  We fix
7123    // this by pretending that the unqualified type was actually
7124    // qualified __strong.
7125    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
7126    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
7127    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
7128
7129    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
7130      return QualType();
7131
7132    if (GC_L == Qualifiers::Strong && RHSCan->isObjCObjectPointerType()) {
7133      return mergeTypes(LHS, getObjCGCQualType(RHS, Qualifiers::Strong));
7134    }
7135    if (GC_R == Qualifiers::Strong && LHSCan->isObjCObjectPointerType()) {
7136      return mergeTypes(getObjCGCQualType(LHS, Qualifiers::Strong), RHS);
7137    }
7138    return QualType();
7139  }
7140
7141  // Okay, qualifiers are equal.
7142
7143  Type::TypeClass LHSClass = LHSCan->getTypeClass();
7144  Type::TypeClass RHSClass = RHSCan->getTypeClass();
7145
7146  // We want to consider the two function types to be the same for these
7147  // comparisons, just force one to the other.
7148  if (LHSClass == Type::FunctionProto) LHSClass = Type::FunctionNoProto;
7149  if (RHSClass == Type::FunctionProto) RHSClass = Type::FunctionNoProto;
7150
7151  // Same as above for arrays
7152  if (LHSClass == Type::VariableArray || LHSClass == Type::IncompleteArray)
7153    LHSClass = Type::ConstantArray;
7154  if (RHSClass == Type::VariableArray || RHSClass == Type::IncompleteArray)
7155    RHSClass = Type::ConstantArray;
7156
7157  // ObjCInterfaces are just specialized ObjCObjects.
7158  if (LHSClass == Type::ObjCInterface) LHSClass = Type::ObjCObject;
7159  if (RHSClass == Type::ObjCInterface) RHSClass = Type::ObjCObject;
7160
7161  // Canonicalize ExtVector -> Vector.
7162  if (LHSClass == Type::ExtVector) LHSClass = Type::Vector;
7163  if (RHSClass == Type::ExtVector) RHSClass = Type::Vector;
7164
7165  // If the canonical type classes don't match.
7166  if (LHSClass != RHSClass) {
7167    // Note that we only have special rules for turning block enum
7168    // returns into block int returns, not vice-versa.
7169    if (const EnumType* ETy = LHS->getAs<EnumType>()) {
7170      return mergeEnumWithInteger(*this, ETy, RHS, false);
7171    }
7172    if (const EnumType* ETy = RHS->getAs<EnumType>()) {
7173      return mergeEnumWithInteger(*this, ETy, LHS, BlockReturnType);
7174    }
7175    // allow block pointer type to match an 'id' type.
7176    if (OfBlockPointer && !BlockReturnType) {
7177       if (LHS->isObjCIdType() && RHS->isBlockPointerType())
7178         return LHS;
7179      if (RHS->isObjCIdType() && LHS->isBlockPointerType())
7180        return RHS;
7181    }
7182
7183    return QualType();
7184  }
7185
7186  // The canonical type classes match.
7187  switch (LHSClass) {
7188#define TYPE(Class, Base)
7189#define ABSTRACT_TYPE(Class, Base)
7190#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
7191#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
7192#define DEPENDENT_TYPE(Class, Base) case Type::Class:
7193#include "clang/AST/TypeNodes.def"
7194    llvm_unreachable("Non-canonical and dependent types shouldn't get here");
7195
7196  case Type::Auto:
7197  case Type::LValueReference:
7198  case Type::RValueReference:
7199  case Type::MemberPointer:
7200    llvm_unreachable("C++ should never be in mergeTypes");
7201
7202  case Type::ObjCInterface:
7203  case Type::IncompleteArray:
7204  case Type::VariableArray:
7205  case Type::FunctionProto:
7206  case Type::ExtVector:
7207    llvm_unreachable("Types are eliminated above");
7208
7209  case Type::Pointer:
7210  {
7211    // Merge two pointer types, while trying to preserve typedef info
7212    QualType LHSPointee = LHS->getAs<PointerType>()->getPointeeType();
7213    QualType RHSPointee = RHS->getAs<PointerType>()->getPointeeType();
7214    if (Unqualified) {
7215      LHSPointee = LHSPointee.getUnqualifiedType();
7216      RHSPointee = RHSPointee.getUnqualifiedType();
7217    }
7218    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, false,
7219                                     Unqualified);
7220    if (ResultType.isNull()) return QualType();
7221    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
7222      return LHS;
7223    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
7224      return RHS;
7225    return getPointerType(ResultType);
7226  }
7227  case Type::BlockPointer:
7228  {
7229    // Merge two block pointer types, while trying to preserve typedef info
7230    QualType LHSPointee = LHS->getAs<BlockPointerType>()->getPointeeType();
7231    QualType RHSPointee = RHS->getAs<BlockPointerType>()->getPointeeType();
7232    if (Unqualified) {
7233      LHSPointee = LHSPointee.getUnqualifiedType();
7234      RHSPointee = RHSPointee.getUnqualifiedType();
7235    }
7236    QualType ResultType = mergeTypes(LHSPointee, RHSPointee, OfBlockPointer,
7237                                     Unqualified);
7238    if (ResultType.isNull()) return QualType();
7239    if (getCanonicalType(LHSPointee) == getCanonicalType(ResultType))
7240      return LHS;
7241    if (getCanonicalType(RHSPointee) == getCanonicalType(ResultType))
7242      return RHS;
7243    return getBlockPointerType(ResultType);
7244  }
7245  case Type::Atomic:
7246  {
7247    // Merge two pointer types, while trying to preserve typedef info
7248    QualType LHSValue = LHS->getAs<AtomicType>()->getValueType();
7249    QualType RHSValue = RHS->getAs<AtomicType>()->getValueType();
7250    if (Unqualified) {
7251      LHSValue = LHSValue.getUnqualifiedType();
7252      RHSValue = RHSValue.getUnqualifiedType();
7253    }
7254    QualType ResultType = mergeTypes(LHSValue, RHSValue, false,
7255                                     Unqualified);
7256    if (ResultType.isNull()) return QualType();
7257    if (getCanonicalType(LHSValue) == getCanonicalType(ResultType))
7258      return LHS;
7259    if (getCanonicalType(RHSValue) == getCanonicalType(ResultType))
7260      return RHS;
7261    return getAtomicType(ResultType);
7262  }
7263  case Type::ConstantArray:
7264  {
7265    const ConstantArrayType* LCAT = getAsConstantArrayType(LHS);
7266    const ConstantArrayType* RCAT = getAsConstantArrayType(RHS);
7267    if (LCAT && RCAT && RCAT->getSize() != LCAT->getSize())
7268      return QualType();
7269
7270    QualType LHSElem = getAsArrayType(LHS)->getElementType();
7271    QualType RHSElem = getAsArrayType(RHS)->getElementType();
7272    if (Unqualified) {
7273      LHSElem = LHSElem.getUnqualifiedType();
7274      RHSElem = RHSElem.getUnqualifiedType();
7275    }
7276
7277    QualType ResultType = mergeTypes(LHSElem, RHSElem, false, Unqualified);
7278    if (ResultType.isNull()) return QualType();
7279    if (LCAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
7280      return LHS;
7281    if (RCAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
7282      return RHS;
7283    if (LCAT) return getConstantArrayType(ResultType, LCAT->getSize(),
7284                                          ArrayType::ArraySizeModifier(), 0);
7285    if (RCAT) return getConstantArrayType(ResultType, RCAT->getSize(),
7286                                          ArrayType::ArraySizeModifier(), 0);
7287    const VariableArrayType* LVAT = getAsVariableArrayType(LHS);
7288    const VariableArrayType* RVAT = getAsVariableArrayType(RHS);
7289    if (LVAT && getCanonicalType(LHSElem) == getCanonicalType(ResultType))
7290      return LHS;
7291    if (RVAT && getCanonicalType(RHSElem) == getCanonicalType(ResultType))
7292      return RHS;
7293    if (LVAT) {
7294      // FIXME: This isn't correct! But tricky to implement because
7295      // the array's size has to be the size of LHS, but the type
7296      // has to be different.
7297      return LHS;
7298    }
7299    if (RVAT) {
7300      // FIXME: This isn't correct! But tricky to implement because
7301      // the array's size has to be the size of RHS, but the type
7302      // has to be different.
7303      return RHS;
7304    }
7305    if (getCanonicalType(LHSElem) == getCanonicalType(ResultType)) return LHS;
7306    if (getCanonicalType(RHSElem) == getCanonicalType(ResultType)) return RHS;
7307    return getIncompleteArrayType(ResultType,
7308                                  ArrayType::ArraySizeModifier(), 0);
7309  }
7310  case Type::FunctionNoProto:
7311    return mergeFunctionTypes(LHS, RHS, OfBlockPointer, Unqualified);
7312  case Type::Record:
7313  case Type::Enum:
7314    return QualType();
7315  case Type::Builtin:
7316    // Only exactly equal builtin types are compatible, which is tested above.
7317    return QualType();
7318  case Type::Complex:
7319    // Distinct complex types are incompatible.
7320    return QualType();
7321  case Type::Vector:
7322    // FIXME: The merged type should be an ExtVector!
7323    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
7324                             RHSCan->getAs<VectorType>()))
7325      return LHS;
7326    return QualType();
7327  case Type::ObjCObject: {
7328    // Check if the types are assignment compatible.
7329    // FIXME: This should be type compatibility, e.g. whether
7330    // "LHS x; RHS x;" at global scope is legal.
7331    const ObjCObjectType* LHSIface = LHS->getAs<ObjCObjectType>();
7332    const ObjCObjectType* RHSIface = RHS->getAs<ObjCObjectType>();
7333    if (canAssignObjCInterfaces(LHSIface, RHSIface))
7334      return LHS;
7335
7336    return QualType();
7337  }
7338  case Type::ObjCObjectPointer: {
7339    if (OfBlockPointer) {
7340      if (canAssignObjCInterfacesInBlockPointer(
7341                                          LHS->getAs<ObjCObjectPointerType>(),
7342                                          RHS->getAs<ObjCObjectPointerType>(),
7343                                          BlockReturnType))
7344        return LHS;
7345      return QualType();
7346    }
7347    if (canAssignObjCInterfaces(LHS->getAs<ObjCObjectPointerType>(),
7348                                RHS->getAs<ObjCObjectPointerType>()))
7349      return LHS;
7350
7351    return QualType();
7352  }
7353  }
7354
7355  llvm_unreachable("Invalid Type::Class!");
7356}
7357
7358bool ASTContext::FunctionTypesMatchOnNSConsumedAttrs(
7359                   const FunctionProtoType *FromFunctionType,
7360                   const FunctionProtoType *ToFunctionType) {
7361  if (FromFunctionType->hasAnyConsumedArgs() !=
7362      ToFunctionType->hasAnyConsumedArgs())
7363    return false;
7364  FunctionProtoType::ExtProtoInfo FromEPI =
7365    FromFunctionType->getExtProtoInfo();
7366  FunctionProtoType::ExtProtoInfo ToEPI =
7367    ToFunctionType->getExtProtoInfo();
7368  if (FromEPI.ConsumedArguments && ToEPI.ConsumedArguments)
7369    for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs();
7370         ArgIdx != NumArgs; ++ArgIdx)  {
7371      if (FromEPI.ConsumedArguments[ArgIdx] !=
7372          ToEPI.ConsumedArguments[ArgIdx])
7373        return false;
7374    }
7375  return true;
7376}
7377
7378/// mergeObjCGCQualifiers - This routine merges ObjC's GC attribute of 'LHS' and
7379/// 'RHS' attributes and returns the merged version; including for function
7380/// return types.
7381QualType ASTContext::mergeObjCGCQualifiers(QualType LHS, QualType RHS) {
7382  QualType LHSCan = getCanonicalType(LHS),
7383  RHSCan = getCanonicalType(RHS);
7384  // If two types are identical, they are compatible.
7385  if (LHSCan == RHSCan)
7386    return LHS;
7387  if (RHSCan->isFunctionType()) {
7388    if (!LHSCan->isFunctionType())
7389      return QualType();
7390    QualType OldReturnType =
7391      cast<FunctionType>(RHSCan.getTypePtr())->getResultType();
7392    QualType NewReturnType =
7393      cast<FunctionType>(LHSCan.getTypePtr())->getResultType();
7394    QualType ResReturnType =
7395      mergeObjCGCQualifiers(NewReturnType, OldReturnType);
7396    if (ResReturnType.isNull())
7397      return QualType();
7398    if (ResReturnType == NewReturnType || ResReturnType == OldReturnType) {
7399      // id foo(); ... __strong id foo(); or: __strong id foo(); ... id foo();
7400      // In either case, use OldReturnType to build the new function type.
7401      const FunctionType *F = LHS->getAs<FunctionType>();
7402      if (const FunctionProtoType *FPT = cast<FunctionProtoType>(F)) {
7403        FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
7404        EPI.ExtInfo = getFunctionExtInfo(LHS);
7405        QualType ResultType =
7406            getFunctionType(OldReturnType, FPT->getArgTypes(), EPI);
7407        return ResultType;
7408      }
7409    }
7410    return QualType();
7411  }
7412
7413  // If the qualifiers are different, the types can still be merged.
7414  Qualifiers LQuals = LHSCan.getLocalQualifiers();
7415  Qualifiers RQuals = RHSCan.getLocalQualifiers();
7416  if (LQuals != RQuals) {
7417    // If any of these qualifiers are different, we have a type mismatch.
7418    if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
7419        LQuals.getAddressSpace() != RQuals.getAddressSpace())
7420      return QualType();
7421
7422    // Exactly one GC qualifier difference is allowed: __strong is
7423    // okay if the other type has no GC qualifier but is an Objective
7424    // C object pointer (i.e. implicitly strong by default).  We fix
7425    // this by pretending that the unqualified type was actually
7426    // qualified __strong.
7427    Qualifiers::GC GC_L = LQuals.getObjCGCAttr();
7428    Qualifiers::GC GC_R = RQuals.getObjCGCAttr();
7429    assert((GC_L != GC_R) && "unequal qualifier sets had only equal elements");
7430
7431    if (GC_L == Qualifiers::Weak || GC_R == Qualifiers::Weak)
7432      return QualType();
7433
7434    if (GC_L == Qualifiers::Strong)
7435      return LHS;
7436    if (GC_R == Qualifiers::Strong)
7437      return RHS;
7438    return QualType();
7439  }
7440
7441  if (LHSCan->isObjCObjectPointerType() && RHSCan->isObjCObjectPointerType()) {
7442    QualType LHSBaseQT = LHS->getAs<ObjCObjectPointerType>()->getPointeeType();
7443    QualType RHSBaseQT = RHS->getAs<ObjCObjectPointerType>()->getPointeeType();
7444    QualType ResQT = mergeObjCGCQualifiers(LHSBaseQT, RHSBaseQT);
7445    if (ResQT == LHSBaseQT)
7446      return LHS;
7447    if (ResQT == RHSBaseQT)
7448      return RHS;
7449  }
7450  return QualType();
7451}
7452
7453//===----------------------------------------------------------------------===//
7454//                         Integer Predicates
7455//===----------------------------------------------------------------------===//
7456
7457unsigned ASTContext::getIntWidth(QualType T) const {
7458  if (const EnumType *ET = dyn_cast<EnumType>(T))
7459    T = ET->getDecl()->getIntegerType();
7460  if (T->isBooleanType())
7461    return 1;
7462  // For builtin types, just use the standard type sizing method
7463  return (unsigned)getTypeSize(T);
7464}
7465
7466QualType ASTContext::getCorrespondingUnsignedType(QualType T) const {
7467  assert(T->hasSignedIntegerRepresentation() && "Unexpected type");
7468
7469  // Turn <4 x signed int> -> <4 x unsigned int>
7470  if (const VectorType *VTy = T->getAs<VectorType>())
7471    return getVectorType(getCorrespondingUnsignedType(VTy->getElementType()),
7472                         VTy->getNumElements(), VTy->getVectorKind());
7473
7474  // For enums, we return the unsigned version of the base type.
7475  if (const EnumType *ETy = T->getAs<EnumType>())
7476    T = ETy->getDecl()->getIntegerType();
7477
7478  const BuiltinType *BTy = T->getAs<BuiltinType>();
7479  assert(BTy && "Unexpected signed integer type");
7480  switch (BTy->getKind()) {
7481  case BuiltinType::Char_S:
7482  case BuiltinType::SChar:
7483    return UnsignedCharTy;
7484  case BuiltinType::Short:
7485    return UnsignedShortTy;
7486  case BuiltinType::Int:
7487    return UnsignedIntTy;
7488  case BuiltinType::Long:
7489    return UnsignedLongTy;
7490  case BuiltinType::LongLong:
7491    return UnsignedLongLongTy;
7492  case BuiltinType::Int128:
7493    return UnsignedInt128Ty;
7494  default:
7495    llvm_unreachable("Unexpected signed integer type");
7496  }
7497}
7498
7499ASTMutationListener::~ASTMutationListener() { }
7500
7501void ASTMutationListener::DeducedReturnType(const FunctionDecl *FD,
7502                                            QualType ReturnType) {}
7503
7504//===----------------------------------------------------------------------===//
7505//                          Builtin Type Computation
7506//===----------------------------------------------------------------------===//
7507
7508/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
7509/// pointer over the consumed characters.  This returns the resultant type.  If
7510/// AllowTypeModifiers is false then modifier like * are not parsed, just basic
7511/// types.  This allows "v2i*" to be parsed as a pointer to a v2i instead of
7512/// a vector of "i*".
7513///
7514/// RequiresICE is filled in on return to indicate whether the value is required
7515/// to be an Integer Constant Expression.
7516static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
7517                                  ASTContext::GetBuiltinTypeError &Error,
7518                                  bool &RequiresICE,
7519                                  bool AllowTypeModifiers) {
7520  // Modifiers.
7521  int HowLong = 0;
7522  bool Signed = false, Unsigned = false;
7523  RequiresICE = false;
7524
7525  // Read the prefixed modifiers first.
7526  bool Done = false;
7527  while (!Done) {
7528    switch (*Str++) {
7529    default: Done = true; --Str; break;
7530    case 'I':
7531      RequiresICE = true;
7532      break;
7533    case 'S':
7534      assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
7535      assert(!Signed && "Can't use 'S' modifier multiple times!");
7536      Signed = true;
7537      break;
7538    case 'U':
7539      assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
7540      assert(!Unsigned && "Can't use 'S' modifier multiple times!");
7541      Unsigned = true;
7542      break;
7543    case 'L':
7544      assert(HowLong <= 2 && "Can't have LLLL modifier");
7545      ++HowLong;
7546      break;
7547    }
7548  }
7549
7550  QualType Type;
7551
7552  // Read the base type.
7553  switch (*Str++) {
7554  default: llvm_unreachable("Unknown builtin type letter!");
7555  case 'v':
7556    assert(HowLong == 0 && !Signed && !Unsigned &&
7557           "Bad modifiers used with 'v'!");
7558    Type = Context.VoidTy;
7559    break;
7560  case 'h':
7561    assert(HowLong == 0 && !Signed && !Unsigned &&
7562           "Bad modifiers used with 'f'!");
7563    Type = Context.HalfTy;
7564    break;
7565  case 'f':
7566    assert(HowLong == 0 && !Signed && !Unsigned &&
7567           "Bad modifiers used with 'f'!");
7568    Type = Context.FloatTy;
7569    break;
7570  case 'd':
7571    assert(HowLong < 2 && !Signed && !Unsigned &&
7572           "Bad modifiers used with 'd'!");
7573    if (HowLong)
7574      Type = Context.LongDoubleTy;
7575    else
7576      Type = Context.DoubleTy;
7577    break;
7578  case 's':
7579    assert(HowLong == 0 && "Bad modifiers used with 's'!");
7580    if (Unsigned)
7581      Type = Context.UnsignedShortTy;
7582    else
7583      Type = Context.ShortTy;
7584    break;
7585  case 'i':
7586    if (HowLong == 3)
7587      Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
7588    else if (HowLong == 2)
7589      Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
7590    else if (HowLong == 1)
7591      Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
7592    else
7593      Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
7594    break;
7595  case 'c':
7596    assert(HowLong == 0 && "Bad modifiers used with 'c'!");
7597    if (Signed)
7598      Type = Context.SignedCharTy;
7599    else if (Unsigned)
7600      Type = Context.UnsignedCharTy;
7601    else
7602      Type = Context.CharTy;
7603    break;
7604  case 'b': // boolean
7605    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
7606    Type = Context.BoolTy;
7607    break;
7608  case 'z':  // size_t.
7609    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
7610    Type = Context.getSizeType();
7611    break;
7612  case 'F':
7613    Type = Context.getCFConstantStringType();
7614    break;
7615  case 'G':
7616    Type = Context.getObjCIdType();
7617    break;
7618  case 'H':
7619    Type = Context.getObjCSelType();
7620    break;
7621  case 'M':
7622    Type = Context.getObjCSuperType();
7623    break;
7624  case 'a':
7625    Type = Context.getBuiltinVaListType();
7626    assert(!Type.isNull() && "builtin va list type not initialized!");
7627    break;
7628  case 'A':
7629    // This is a "reference" to a va_list; however, what exactly
7630    // this means depends on how va_list is defined. There are two
7631    // different kinds of va_list: ones passed by value, and ones
7632    // passed by reference.  An example of a by-value va_list is
7633    // x86, where va_list is a char*. An example of by-ref va_list
7634    // is x86-64, where va_list is a __va_list_tag[1]. For x86,
7635    // we want this argument to be a char*&; for x86-64, we want
7636    // it to be a __va_list_tag*.
7637    Type = Context.getBuiltinVaListType();
7638    assert(!Type.isNull() && "builtin va list type not initialized!");
7639    if (Type->isArrayType())
7640      Type = Context.getArrayDecayedType(Type);
7641    else
7642      Type = Context.getLValueReferenceType(Type);
7643    break;
7644  case 'V': {
7645    char *End;
7646    unsigned NumElements = strtoul(Str, &End, 10);
7647    assert(End != Str && "Missing vector size");
7648    Str = End;
7649
7650    QualType ElementType = DecodeTypeFromStr(Str, Context, Error,
7651                                             RequiresICE, false);
7652    assert(!RequiresICE && "Can't require vector ICE");
7653
7654    // TODO: No way to make AltiVec vectors in builtins yet.
7655    Type = Context.getVectorType(ElementType, NumElements,
7656                                 VectorType::GenericVector);
7657    break;
7658  }
7659  case 'E': {
7660    char *End;
7661
7662    unsigned NumElements = strtoul(Str, &End, 10);
7663    assert(End != Str && "Missing vector size");
7664
7665    Str = End;
7666
7667    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
7668                                             false);
7669    Type = Context.getExtVectorType(ElementType, NumElements);
7670    break;
7671  }
7672  case 'X': {
7673    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, RequiresICE,
7674                                             false);
7675    assert(!RequiresICE && "Can't require complex ICE");
7676    Type = Context.getComplexType(ElementType);
7677    break;
7678  }
7679  case 'Y' : {
7680    Type = Context.getPointerDiffType();
7681    break;
7682  }
7683  case 'P':
7684    Type = Context.getFILEType();
7685    if (Type.isNull()) {
7686      Error = ASTContext::GE_Missing_stdio;
7687      return QualType();
7688    }
7689    break;
7690  case 'J':
7691    if (Signed)
7692      Type = Context.getsigjmp_bufType();
7693    else
7694      Type = Context.getjmp_bufType();
7695
7696    if (Type.isNull()) {
7697      Error = ASTContext::GE_Missing_setjmp;
7698      return QualType();
7699    }
7700    break;
7701  case 'K':
7702    assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'K'!");
7703    Type = Context.getucontext_tType();
7704
7705    if (Type.isNull()) {
7706      Error = ASTContext::GE_Missing_ucontext;
7707      return QualType();
7708    }
7709    break;
7710  case 'p':
7711    Type = Context.getProcessIDType();
7712    break;
7713  }
7714
7715  // If there are modifiers and if we're allowed to parse them, go for it.
7716  Done = !AllowTypeModifiers;
7717  while (!Done) {
7718    switch (char c = *Str++) {
7719    default: Done = true; --Str; break;
7720    case '*':
7721    case '&': {
7722      // Both pointers and references can have their pointee types
7723      // qualified with an address space.
7724      char *End;
7725      unsigned AddrSpace = strtoul(Str, &End, 10);
7726      if (End != Str && AddrSpace != 0) {
7727        Type = Context.getAddrSpaceQualType(Type, AddrSpace);
7728        Str = End;
7729      }
7730      if (c == '*')
7731        Type = Context.getPointerType(Type);
7732      else
7733        Type = Context.getLValueReferenceType(Type);
7734      break;
7735    }
7736    // FIXME: There's no way to have a built-in with an rvalue ref arg.
7737    case 'C':
7738      Type = Type.withConst();
7739      break;
7740    case 'D':
7741      Type = Context.getVolatileType(Type);
7742      break;
7743    case 'R':
7744      Type = Type.withRestrict();
7745      break;
7746    }
7747  }
7748
7749  assert((!RequiresICE || Type->isIntegralOrEnumerationType()) &&
7750         "Integer constant 'I' type must be an integer");
7751
7752  return Type;
7753}
7754
7755/// GetBuiltinType - Return the type for the specified builtin.
7756QualType ASTContext::GetBuiltinType(unsigned Id,
7757                                    GetBuiltinTypeError &Error,
7758                                    unsigned *IntegerConstantArgs) const {
7759  const char *TypeStr = BuiltinInfo.GetTypeString(Id);
7760
7761  SmallVector<QualType, 8> ArgTypes;
7762
7763  bool RequiresICE = false;
7764  Error = GE_None;
7765  QualType ResType = DecodeTypeFromStr(TypeStr, *this, Error,
7766                                       RequiresICE, true);
7767  if (Error != GE_None)
7768    return QualType();
7769
7770  assert(!RequiresICE && "Result of intrinsic cannot be required to be an ICE");
7771
7772  while (TypeStr[0] && TypeStr[0] != '.') {
7773    QualType Ty = DecodeTypeFromStr(TypeStr, *this, Error, RequiresICE, true);
7774    if (Error != GE_None)
7775      return QualType();
7776
7777    // If this argument is required to be an IntegerConstantExpression and the
7778    // caller cares, fill in the bitmask we return.
7779    if (RequiresICE && IntegerConstantArgs)
7780      *IntegerConstantArgs |= 1 << ArgTypes.size();
7781
7782    // Do array -> pointer decay.  The builtin should use the decayed type.
7783    if (Ty->isArrayType())
7784      Ty = getArrayDecayedType(Ty);
7785
7786    ArgTypes.push_back(Ty);
7787  }
7788
7789  assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
7790         "'.' should only occur at end of builtin type list!");
7791
7792  FunctionType::ExtInfo EI;
7793  if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
7794
7795  bool Variadic = (TypeStr[0] == '.');
7796
7797  // We really shouldn't be making a no-proto type here, especially in C++.
7798  if (ArgTypes.empty() && Variadic)
7799    return getFunctionNoProtoType(ResType, EI);
7800
7801  FunctionProtoType::ExtProtoInfo EPI;
7802  EPI.ExtInfo = EI;
7803  EPI.Variadic = Variadic;
7804
7805  return getFunctionType(ResType, ArgTypes, EPI);
7806}
7807
7808GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
7809  if (!FD->isExternallyVisible())
7810    return GVA_Internal;
7811
7812  GVALinkage External = GVA_StrongExternal;
7813  switch (FD->getTemplateSpecializationKind()) {
7814  case TSK_Undeclared:
7815  case TSK_ExplicitSpecialization:
7816    External = GVA_StrongExternal;
7817    break;
7818
7819  case TSK_ExplicitInstantiationDefinition:
7820    return GVA_ExplicitTemplateInstantiation;
7821
7822  case TSK_ExplicitInstantiationDeclaration:
7823  case TSK_ImplicitInstantiation:
7824    External = GVA_TemplateInstantiation;
7825    break;
7826  }
7827
7828  if (!FD->isInlined())
7829    return External;
7830
7831  if ((!getLangOpts().CPlusPlus && !getLangOpts().MicrosoftMode) ||
7832      FD->hasAttr<GNUInlineAttr>()) {
7833    // GNU or C99 inline semantics. Determine whether this symbol should be
7834    // externally visible.
7835    if (FD->isInlineDefinitionExternallyVisible())
7836      return External;
7837
7838    // C99 inline semantics, where the symbol is not externally visible.
7839    return GVA_C99Inline;
7840  }
7841
7842  // C++0x [temp.explicit]p9:
7843  //   [ Note: The intent is that an inline function that is the subject of
7844  //   an explicit instantiation declaration will still be implicitly
7845  //   instantiated when used so that the body can be considered for
7846  //   inlining, but that no out-of-line copy of the inline function would be
7847  //   generated in the translation unit. -- end note ]
7848  if (FD->getTemplateSpecializationKind()
7849                                       == TSK_ExplicitInstantiationDeclaration)
7850    return GVA_C99Inline;
7851
7852  return GVA_CXXInline;
7853}
7854
7855GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
7856  if (!VD->isExternallyVisible())
7857    return GVA_Internal;
7858
7859  // If this is a static data member, compute the kind of template
7860  // specialization. Otherwise, this variable is not part of a
7861  // template.
7862  TemplateSpecializationKind TSK = TSK_Undeclared;
7863  if (VD->isStaticDataMember())
7864    TSK = VD->getTemplateSpecializationKind();
7865
7866  switch (TSK) {
7867  case TSK_Undeclared:
7868  case TSK_ExplicitSpecialization:
7869    return GVA_StrongExternal;
7870
7871  case TSK_ExplicitInstantiationDeclaration:
7872    llvm_unreachable("Variable should not be instantiated");
7873  // Fall through to treat this like any other instantiation.
7874
7875  case TSK_ExplicitInstantiationDefinition:
7876    return GVA_ExplicitTemplateInstantiation;
7877
7878  case TSK_ImplicitInstantiation:
7879    return GVA_TemplateInstantiation;
7880  }
7881
7882  llvm_unreachable("Invalid Linkage!");
7883}
7884
7885bool ASTContext::DeclMustBeEmitted(const Decl *D) {
7886  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
7887    if (!VD->isFileVarDecl())
7888      return false;
7889  } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
7890    // We never need to emit an uninstantiated function template.
7891    if (FD->getTemplatedKind() == FunctionDecl::TK_FunctionTemplate)
7892      return false;
7893  } else
7894    return false;
7895
7896  // If this is a member of a class template, we do not need to emit it.
7897  if (D->getDeclContext()->isDependentContext())
7898    return false;
7899
7900  // Weak references don't produce any output by themselves.
7901  if (D->hasAttr<WeakRefAttr>())
7902    return false;
7903
7904  // Aliases and used decls are required.
7905  if (D->hasAttr<AliasAttr>() || D->hasAttr<UsedAttr>())
7906    return true;
7907
7908  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
7909    // Forward declarations aren't required.
7910    if (!FD->doesThisDeclarationHaveABody())
7911      return FD->doesDeclarationForceExternallyVisibleDefinition();
7912
7913    // Constructors and destructors are required.
7914    if (FD->hasAttr<ConstructorAttr>() || FD->hasAttr<DestructorAttr>())
7915      return true;
7916
7917    // The key function for a class is required.  This rule only comes
7918    // into play when inline functions can be key functions, though.
7919    if (getTargetInfo().getCXXABI().canKeyFunctionBeInline()) {
7920      if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
7921        const CXXRecordDecl *RD = MD->getParent();
7922        if (MD->isOutOfLine() && RD->isDynamicClass()) {
7923          const CXXMethodDecl *KeyFunc = getCurrentKeyFunction(RD);
7924          if (KeyFunc && KeyFunc->getCanonicalDecl() == MD->getCanonicalDecl())
7925            return true;
7926        }
7927      }
7928    }
7929
7930    GVALinkage Linkage = GetGVALinkageForFunction(FD);
7931
7932    // static, static inline, always_inline, and extern inline functions can
7933    // always be deferred.  Normal inline functions can be deferred in C99/C++.
7934    // Implicit template instantiations can also be deferred in C++.
7935    if (Linkage == GVA_Internal  || Linkage == GVA_C99Inline ||
7936        Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
7937      return false;
7938    return true;
7939  }
7940
7941  const VarDecl *VD = cast<VarDecl>(D);
7942  assert(VD->isFileVarDecl() && "Expected file scoped var");
7943
7944  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
7945    return false;
7946
7947  // Variables that can be needed in other TUs are required.
7948  GVALinkage L = GetGVALinkageForVariable(VD);
7949  if (L != GVA_Internal && L != GVA_TemplateInstantiation)
7950    return true;
7951
7952  // Variables that have destruction with side-effects are required.
7953  if (VD->getType().isDestructedType())
7954    return true;
7955
7956  // Variables that have initialization with side-effects are required.
7957  if (VD->getInit() && VD->getInit()->HasSideEffects(*this))
7958    return true;
7959
7960  return false;
7961}
7962
7963CallingConv ASTContext::getDefaultCXXMethodCallConv(bool isVariadic) {
7964  // Pass through to the C++ ABI object
7965  return ABI->getDefaultMethodCallConv(isVariadic);
7966}
7967
7968CallingConv ASTContext::getCanonicalCallConv(CallingConv CC) const {
7969  if (CC == CC_C && !LangOpts.MRTD &&
7970      getTargetInfo().getCXXABI().isMemberFunctionCCDefault())
7971    return CC_Default;
7972  return CC;
7973}
7974
7975bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
7976  // Pass through to the C++ ABI object
7977  return ABI->isNearlyEmpty(RD);
7978}
7979
7980MangleContext *ASTContext::createMangleContext() {
7981  switch (Target->getCXXABI().getKind()) {
7982  case TargetCXXABI::GenericAArch64:
7983  case TargetCXXABI::GenericItanium:
7984  case TargetCXXABI::GenericARM:
7985  case TargetCXXABI::iOS:
7986    return createItaniumMangleContext(*this, getDiagnostics());
7987  case TargetCXXABI::Microsoft:
7988    return createMicrosoftMangleContext(*this, getDiagnostics());
7989  }
7990  llvm_unreachable("Unsupported ABI");
7991}
7992
7993CXXABI::~CXXABI() {}
7994
7995size_t ASTContext::getSideTableAllocatedMemory() const {
7996  return ASTRecordLayouts.getMemorySize() +
7997         llvm::capacity_in_bytes(ObjCLayouts) +
7998         llvm::capacity_in_bytes(KeyFunctions) +
7999         llvm::capacity_in_bytes(ObjCImpls) +
8000         llvm::capacity_in_bytes(BlockVarCopyInits) +
8001         llvm::capacity_in_bytes(DeclAttrs) +
8002         llvm::capacity_in_bytes(TemplateOrInstantiation) +
8003         llvm::capacity_in_bytes(InstantiatedFromUsingDecl) +
8004         llvm::capacity_in_bytes(InstantiatedFromUsingShadowDecl) +
8005         llvm::capacity_in_bytes(InstantiatedFromUnnamedFieldDecl) +
8006         llvm::capacity_in_bytes(OverriddenMethods) +
8007         llvm::capacity_in_bytes(Types) +
8008         llvm::capacity_in_bytes(VariableArrayTypes) +
8009         llvm::capacity_in_bytes(ClassScopeSpecializationPattern);
8010}
8011
8012void ASTContext::setManglingNumber(const NamedDecl *ND, unsigned Number) {
8013  if (Number > 1)
8014    MangleNumbers[ND] = Number;
8015}
8016
8017unsigned ASTContext::getManglingNumber(const NamedDecl *ND) const {
8018  llvm::DenseMap<const NamedDecl *, unsigned>::const_iterator I =
8019    MangleNumbers.find(ND);
8020  return I != MangleNumbers.end() ? I->second : 1;
8021}
8022
8023MangleNumberingContext &
8024ASTContext::getManglingNumberContext(const DeclContext *DC) {
8025  return MangleNumberingContexts[DC];
8026}
8027
8028void ASTContext::setParameterIndex(const ParmVarDecl *D, unsigned int index) {
8029  ParamIndices[D] = index;
8030}
8031
8032unsigned ASTContext::getParameterIndex(const ParmVarDecl *D) const {
8033  ParameterIndexTable::const_iterator I = ParamIndices.find(D);
8034  assert(I != ParamIndices.end() &&
8035         "ParmIndices lacks entry set by ParmVarDecl");
8036  return I->second;
8037}
8038
8039APValue *
8040ASTContext::getMaterializedTemporaryValue(const MaterializeTemporaryExpr *E,
8041                                          bool MayCreate) {
8042  assert(E && E->getStorageDuration() == SD_Static &&
8043         "don't need to cache the computed value for this temporary");
8044  if (MayCreate)
8045    return &MaterializedTemporaryValues[E];
8046
8047  llvm::DenseMap<const MaterializeTemporaryExpr *, APValue>::iterator I =
8048      MaterializedTemporaryValues.find(E);
8049  return I == MaterializedTemporaryValues.end() ? 0 : &I->second;
8050}
8051
8052bool ASTContext::AtomicUsesUnsupportedLibcall(const AtomicExpr *E) const {
8053  const llvm::Triple &T = getTargetInfo().getTriple();
8054  if (!T.isOSDarwin())
8055    return false;
8056
8057  QualType AtomicTy = E->getPtr()->getType()->getPointeeType();
8058  CharUnits sizeChars = getTypeSizeInChars(AtomicTy);
8059  uint64_t Size = sizeChars.getQuantity();
8060  CharUnits alignChars = getTypeAlignInChars(AtomicTy);
8061  unsigned Align = alignChars.getQuantity();
8062  unsigned MaxInlineWidthInBits = getTargetInfo().getMaxAtomicInlineWidth();
8063  return (Size != Align || toBits(sizeChars) > MaxInlineWidthInBits);
8064}
8065
8066namespace {
8067
8068  /// \brief A \c RecursiveASTVisitor that builds a map from nodes to their
8069  /// parents as defined by the \c RecursiveASTVisitor.
8070  ///
8071  /// Note that the relationship described here is purely in terms of AST
8072  /// traversal - there are other relationships (for example declaration context)
8073  /// in the AST that are better modeled by special matchers.
8074  ///
8075  /// FIXME: Currently only builds up the map using \c Stmt and \c Decl nodes.
8076  class ParentMapASTVisitor : public RecursiveASTVisitor<ParentMapASTVisitor> {
8077
8078  public:
8079    /// \brief Builds and returns the translation unit's parent map.
8080    ///
8081    ///  The caller takes ownership of the returned \c ParentMap.
8082    static ASTContext::ParentMap *buildMap(TranslationUnitDecl &TU) {
8083      ParentMapASTVisitor Visitor(new ASTContext::ParentMap);
8084      Visitor.TraverseDecl(&TU);
8085      return Visitor.Parents;
8086    }
8087
8088  private:
8089    typedef RecursiveASTVisitor<ParentMapASTVisitor> VisitorBase;
8090
8091    ParentMapASTVisitor(ASTContext::ParentMap *Parents) : Parents(Parents) {
8092    }
8093
8094    bool shouldVisitTemplateInstantiations() const {
8095      return true;
8096    }
8097    bool shouldVisitImplicitCode() const {
8098      return true;
8099    }
8100    // Disables data recursion. We intercept Traverse* methods in the RAV, which
8101    // are not triggered during data recursion.
8102    bool shouldUseDataRecursionFor(clang::Stmt *S) const {
8103      return false;
8104    }
8105
8106    template <typename T>
8107    bool TraverseNode(T *Node, bool(VisitorBase:: *traverse) (T *)) {
8108      if (Node == NULL)
8109        return true;
8110      if (ParentStack.size() > 0)
8111        // FIXME: Currently we add the same parent multiple times, for example
8112        // when we visit all subexpressions of template instantiations; this is
8113        // suboptimal, bug benign: the only way to visit those is with
8114        // hasAncestor / hasParent, and those do not create new matches.
8115        // The plan is to enable DynTypedNode to be storable in a map or hash
8116        // map. The main problem there is to implement hash functions /
8117        // comparison operators for all types that DynTypedNode supports that
8118        // do not have pointer identity.
8119        (*Parents)[Node].push_back(ParentStack.back());
8120      ParentStack.push_back(ast_type_traits::DynTypedNode::create(*Node));
8121      bool Result = (this ->* traverse) (Node);
8122      ParentStack.pop_back();
8123      return Result;
8124    }
8125
8126    bool TraverseDecl(Decl *DeclNode) {
8127      return TraverseNode(DeclNode, &VisitorBase::TraverseDecl);
8128    }
8129
8130    bool TraverseStmt(Stmt *StmtNode) {
8131      return TraverseNode(StmtNode, &VisitorBase::TraverseStmt);
8132    }
8133
8134    ASTContext::ParentMap *Parents;
8135    llvm::SmallVector<ast_type_traits::DynTypedNode, 16> ParentStack;
8136
8137    friend class RecursiveASTVisitor<ParentMapASTVisitor>;
8138  };
8139
8140} // end namespace
8141
8142ASTContext::ParentVector
8143ASTContext::getParents(const ast_type_traits::DynTypedNode &Node) {
8144  assert(Node.getMemoizationData() &&
8145         "Invariant broken: only nodes that support memoization may be "
8146         "used in the parent map.");
8147  if (!AllParents) {
8148    // We always need to run over the whole translation unit, as
8149    // hasAncestor can escape any subtree.
8150    AllParents.reset(
8151        ParentMapASTVisitor::buildMap(*getTranslationUnitDecl()));
8152  }
8153  ParentMap::const_iterator I = AllParents->find(Node.getMemoizationData());
8154  if (I == AllParents->end()) {
8155    return ParentVector();
8156  }
8157  return I->second;
8158}
8159
8160bool
8161ASTContext::ObjCMethodsAreEqual(const ObjCMethodDecl *MethodDecl,
8162                                const ObjCMethodDecl *MethodImpl) {
8163  // No point trying to match an unavailable/deprecated mothod.
8164  if (MethodDecl->hasAttr<UnavailableAttr>()
8165      || MethodDecl->hasAttr<DeprecatedAttr>())
8166    return false;
8167  if (MethodDecl->getObjCDeclQualifier() !=
8168      MethodImpl->getObjCDeclQualifier())
8169    return false;
8170  if (!hasSameType(MethodDecl->getResultType(),
8171                   MethodImpl->getResultType()))
8172    return false;
8173
8174  if (MethodDecl->param_size() != MethodImpl->param_size())
8175    return false;
8176
8177  for (ObjCMethodDecl::param_const_iterator IM = MethodImpl->param_begin(),
8178       IF = MethodDecl->param_begin(), EM = MethodImpl->param_end(),
8179       EF = MethodDecl->param_end();
8180       IM != EM && IF != EF; ++IM, ++IF) {
8181    const ParmVarDecl *DeclVar = (*IF);
8182    const ParmVarDecl *ImplVar = (*IM);
8183    if (ImplVar->getObjCDeclQualifier() != DeclVar->getObjCDeclQualifier())
8184      return false;
8185    if (!hasSameType(DeclVar->getType(), ImplVar->getType()))
8186      return false;
8187  }
8188  return (MethodDecl->isVariadic() == MethodImpl->isVariadic());
8189
8190}
8191