1 //===--- ASTWriterDecl.cpp - Declaration Serialization --------------------===//
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 serialization for Declarations.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/Serialization/ASTWriter.h"
15 #include "clang/Serialization/ASTReader.h"
16 #include "ASTCommon.h"
17 #include "clang/AST/DeclVisitor.h"
18 #include "clang/AST/DeclCXX.h"
19 #include "clang/AST/DeclTemplate.h"
20 #include "clang/AST/Expr.h"
21 #include "clang/AST/DeclContextInternals.h"
22 #include "clang/Basic/SourceManager.h"
23 #include "llvm/ADT/Twine.h"
24 #include "llvm/Bitcode/BitstreamWriter.h"
25 #include "llvm/Support/ErrorHandling.h"
26 using namespace clang;
27 using namespace serialization;
28 
29 //===----------------------------------------------------------------------===//
30 // Declaration serialization
31 //===----------------------------------------------------------------------===//
32 
33 namespace clang {
34   class ASTDeclWriter : public DeclVisitor<ASTDeclWriter, void> {
35 
36     ASTWriter &Writer;
37     ASTContext &Context;
38     typedef ASTWriter::RecordData RecordData;
39     RecordData &Record;
40 
41   public:
42     serialization::DeclCode Code;
43     unsigned AbbrevToUse;
44 
45     ASTDeclWriter(ASTWriter &Writer, ASTContext &Context, RecordData &Record)
46       : Writer(Writer), Context(Context), Record(Record) {
47     }
48 
49     void Visit(Decl *D);
50 
51     void VisitDecl(Decl *D);
52     void VisitTranslationUnitDecl(TranslationUnitDecl *D);
53     void VisitNamedDecl(NamedDecl *D);
54     void VisitLabelDecl(LabelDecl *LD);
55     void VisitNamespaceDecl(NamespaceDecl *D);
56     void VisitUsingDirectiveDecl(UsingDirectiveDecl *D);
57     void VisitNamespaceAliasDecl(NamespaceAliasDecl *D);
58     void VisitTypeDecl(TypeDecl *D);
59     void VisitTypedefNameDecl(TypedefNameDecl *D);
60     void VisitTypedefDecl(TypedefDecl *D);
61     void VisitTypeAliasDecl(TypeAliasDecl *D);
62     void VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D);
63     void VisitTagDecl(TagDecl *D);
64     void VisitEnumDecl(EnumDecl *D);
65     void VisitRecordDecl(RecordDecl *D);
66     void VisitCXXRecordDecl(CXXRecordDecl *D);
67     void VisitClassTemplateSpecializationDecl(
68                                             ClassTemplateSpecializationDecl *D);
69     void VisitClassTemplatePartialSpecializationDecl(
70                                      ClassTemplatePartialSpecializationDecl *D);
71     void VisitClassScopeFunctionSpecializationDecl(
72                                        ClassScopeFunctionSpecializationDecl *D);
73     void VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D);
74     void VisitValueDecl(ValueDecl *D);
75     void VisitEnumConstantDecl(EnumConstantDecl *D);
76     void VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D);
77     void VisitDeclaratorDecl(DeclaratorDecl *D);
78     void VisitFunctionDecl(FunctionDecl *D);
79     void VisitCXXMethodDecl(CXXMethodDecl *D);
80     void VisitCXXConstructorDecl(CXXConstructorDecl *D);
81     void VisitCXXDestructorDecl(CXXDestructorDecl *D);
82     void VisitCXXConversionDecl(CXXConversionDecl *D);
83     void VisitFieldDecl(FieldDecl *D);
84     void VisitIndirectFieldDecl(IndirectFieldDecl *D);
85     void VisitVarDecl(VarDecl *D);
86     void VisitImplicitParamDecl(ImplicitParamDecl *D);
87     void VisitParmVarDecl(ParmVarDecl *D);
88     void VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D);
89     void VisitTemplateDecl(TemplateDecl *D);
90     void VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D);
91     void VisitClassTemplateDecl(ClassTemplateDecl *D);
92     void VisitFunctionTemplateDecl(FunctionTemplateDecl *D);
93     void VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D);
94     void VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D);
95     void VisitUsingDecl(UsingDecl *D);
96     void VisitUsingShadowDecl(UsingShadowDecl *D);
97     void VisitLinkageSpecDecl(LinkageSpecDecl *D);
98     void VisitFileScopeAsmDecl(FileScopeAsmDecl *D);
99     void VisitImportDecl(ImportDecl *D);
100     void VisitAccessSpecDecl(AccessSpecDecl *D);
101     void VisitFriendDecl(FriendDecl *D);
102     void VisitFriendTemplateDecl(FriendTemplateDecl *D);
103     void VisitStaticAssertDecl(StaticAssertDecl *D);
104     void VisitBlockDecl(BlockDecl *D);
105 
106     void VisitDeclContext(DeclContext *DC, uint64_t LexicalOffset,
107                           uint64_t VisibleOffset);
108     template <typename T> void VisitRedeclarable(Redeclarable<T> *D);
109 
110 
111     // FIXME: Put in the same order is DeclNodes.td?
112     void VisitObjCMethodDecl(ObjCMethodDecl *D);
113     void VisitObjCContainerDecl(ObjCContainerDecl *D);
114     void VisitObjCInterfaceDecl(ObjCInterfaceDecl *D);
115     void VisitObjCIvarDecl(ObjCIvarDecl *D);
116     void VisitObjCProtocolDecl(ObjCProtocolDecl *D);
117     void VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D);
118     void VisitObjCCategoryDecl(ObjCCategoryDecl *D);
119     void VisitObjCImplDecl(ObjCImplDecl *D);
120     void VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D);
121     void VisitObjCImplementationDecl(ObjCImplementationDecl *D);
122     void VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D);
123     void VisitObjCPropertyDecl(ObjCPropertyDecl *D);
124     void VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D);
125   };
126 }
127 
128 void ASTDeclWriter::Visit(Decl *D) {
129   DeclVisitor<ASTDeclWriter>::Visit(D);
130 
131   // Source locations require array (variable-length) abbreviations.  The
132   // abbreviation infrastructure requires that arrays are encoded last, so
133   // we handle it here in the case of those classes derived from DeclaratorDecl
134   if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D)){
135     Writer.AddTypeSourceInfo(DD->getTypeSourceInfo(), Record);
136   }
137 
138   // Handle FunctionDecl's body here and write it after all other Stmts/Exprs
139   // have been written. We want it last because we will not read it back when
140   // retrieving it from the AST, we'll just lazily set the offset.
141   if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
142     Record.push_back(FD->doesThisDeclarationHaveABody());
143     if (FD->doesThisDeclarationHaveABody())
144       Writer.AddStmt(FD->getBody());
145   }
146 }
147 
148 void ASTDeclWriter::VisitDecl(Decl *D) {
149   Writer.AddDeclRef(cast_or_null<Decl>(D->getDeclContext()), Record);
150   Writer.AddDeclRef(cast_or_null<Decl>(D->getLexicalDeclContext()), Record);
151   Record.push_back(D->isInvalidDecl());
152   Record.push_back(D->hasAttrs());
153   if (D->hasAttrs())
154     Writer.WriteAttributes(D->getAttrs(), Record);
155   Record.push_back(D->isImplicit());
156   Record.push_back(D->isUsed(false));
157   Record.push_back(D->isReferenced());
158   Record.push_back(D->isTopLevelDeclInObjCContainer());
159   Record.push_back(D->getAccess());
160   Record.push_back(D->isModulePrivate());
161   Record.push_back(Writer.inferSubmoduleIDFromLocation(D->getLocation()));
162 }
163 
164 void ASTDeclWriter::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
165   llvm_unreachable("Translation units aren't directly serialized");
166 }
167 
168 void ASTDeclWriter::VisitNamedDecl(NamedDecl *D) {
169   VisitDecl(D);
170   Writer.AddDeclarationName(D->getDeclName(), Record);
171 }
172 
173 void ASTDeclWriter::VisitTypeDecl(TypeDecl *D) {
174   VisitNamedDecl(D);
175   Writer.AddSourceLocation(D->getLocStart(), Record);
176   Writer.AddTypeRef(QualType(D->getTypeForDecl(), 0), Record);
177 }
178 
179 void ASTDeclWriter::VisitTypedefNameDecl(TypedefNameDecl *D) {
180   VisitRedeclarable(D);
181   VisitTypeDecl(D);
182   Writer.AddTypeSourceInfo(D->getTypeSourceInfo(), Record);
183 }
184 
185 void ASTDeclWriter::VisitTypedefDecl(TypedefDecl *D) {
186   VisitTypedefNameDecl(D);
187   if (!D->hasAttrs() &&
188       !D->isImplicit() &&
189       !D->isUsed(false) &&
190       D->getFirstDeclaration() == D->getMostRecentDecl() &&
191       !D->isInvalidDecl() &&
192       !D->isReferenced() &&
193       !D->isTopLevelDeclInObjCContainer() &&
194       D->getAccess() == AS_none &&
195       !D->isModulePrivate() &&
196       D->getDeclName().getNameKind() == DeclarationName::Identifier)
197     AbbrevToUse = Writer.getDeclTypedefAbbrev();
198 
199   Code = serialization::DECL_TYPEDEF;
200 }
201 
202 void ASTDeclWriter::VisitTypeAliasDecl(TypeAliasDecl *D) {
203   VisitTypedefNameDecl(D);
204   Code = serialization::DECL_TYPEALIAS;
205 }
206 
207 void ASTDeclWriter::VisitTagDecl(TagDecl *D) {
208   VisitRedeclarable(D);
209   VisitTypeDecl(D);
210   Record.push_back(D->getIdentifierNamespace());
211   Record.push_back((unsigned)D->getTagKind()); // FIXME: stable encoding
212   Record.push_back(D->isCompleteDefinition());
213   Record.push_back(D->isEmbeddedInDeclarator());
214   Record.push_back(D->isFreeStanding());
215   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
216   Record.push_back(D->hasExtInfo());
217   if (D->hasExtInfo())
218     Writer.AddQualifierInfo(*D->getExtInfo(), Record);
219   else
220     Writer.AddDeclRef(D->getTypedefNameForAnonDecl(), Record);
221 }
222 
223 void ASTDeclWriter::VisitEnumDecl(EnumDecl *D) {
224   VisitTagDecl(D);
225   Writer.AddTypeSourceInfo(D->getIntegerTypeSourceInfo(), Record);
226   if (!D->getIntegerTypeSourceInfo())
227     Writer.AddTypeRef(D->getIntegerType(), Record);
228   Writer.AddTypeRef(D->getPromotionType(), Record);
229   Record.push_back(D->getNumPositiveBits());
230   Record.push_back(D->getNumNegativeBits());
231   Record.push_back(D->isScoped());
232   Record.push_back(D->isScopedUsingClassTag());
233   Record.push_back(D->isFixed());
234   if (MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo()) {
235     Writer.AddDeclRef(MemberInfo->getInstantiatedFrom(), Record);
236     Record.push_back(MemberInfo->getTemplateSpecializationKind());
237     Writer.AddSourceLocation(MemberInfo->getPointOfInstantiation(), Record);
238   } else {
239     Writer.AddDeclRef(0, Record);
240   }
241 
242   if (!D->hasAttrs() &&
243       !D->isImplicit() &&
244       !D->isUsed(false) &&
245       !D->hasExtInfo() &&
246       D->getFirstDeclaration() == D->getMostRecentDecl() &&
247       !D->isInvalidDecl() &&
248       !D->isReferenced() &&
249       !D->isTopLevelDeclInObjCContainer() &&
250       D->getAccess() == AS_none &&
251       !D->isModulePrivate() &&
252       !CXXRecordDecl::classofKind(D->getKind()) &&
253       !D->getIntegerTypeSourceInfo() &&
254       D->getDeclName().getNameKind() == DeclarationName::Identifier)
255     AbbrevToUse = Writer.getDeclEnumAbbrev();
256 
257   Code = serialization::DECL_ENUM;
258 }
259 
260 void ASTDeclWriter::VisitRecordDecl(RecordDecl *D) {
261   VisitTagDecl(D);
262   Record.push_back(D->hasFlexibleArrayMember());
263   Record.push_back(D->isAnonymousStructOrUnion());
264   Record.push_back(D->hasObjectMember());
265 
266   if (!D->hasAttrs() &&
267       !D->isImplicit() &&
268       !D->isUsed(false) &&
269       !D->hasExtInfo() &&
270       D->getFirstDeclaration() == D->getMostRecentDecl() &&
271       !D->isInvalidDecl() &&
272       !D->isReferenced() &&
273       !D->isTopLevelDeclInObjCContainer() &&
274       D->getAccess() == AS_none &&
275       !D->isModulePrivate() &&
276       !CXXRecordDecl::classofKind(D->getKind()) &&
277       D->getDeclName().getNameKind() == DeclarationName::Identifier)
278     AbbrevToUse = Writer.getDeclRecordAbbrev();
279 
280   Code = serialization::DECL_RECORD;
281 }
282 
283 void ASTDeclWriter::VisitValueDecl(ValueDecl *D) {
284   VisitNamedDecl(D);
285   Writer.AddTypeRef(D->getType(), Record);
286 }
287 
288 void ASTDeclWriter::VisitEnumConstantDecl(EnumConstantDecl *D) {
289   VisitValueDecl(D);
290   Record.push_back(D->getInitExpr()? 1 : 0);
291   if (D->getInitExpr())
292     Writer.AddStmt(D->getInitExpr());
293   Writer.AddAPSInt(D->getInitVal(), Record);
294 
295   Code = serialization::DECL_ENUM_CONSTANT;
296 }
297 
298 void ASTDeclWriter::VisitDeclaratorDecl(DeclaratorDecl *D) {
299   VisitValueDecl(D);
300   Writer.AddSourceLocation(D->getInnerLocStart(), Record);
301   Record.push_back(D->hasExtInfo());
302   if (D->hasExtInfo())
303     Writer.AddQualifierInfo(*D->getExtInfo(), Record);
304 }
305 
306 void ASTDeclWriter::VisitFunctionDecl(FunctionDecl *D) {
307   VisitRedeclarable(D);
308   VisitDeclaratorDecl(D);
309 
310   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
311   Record.push_back(D->getIdentifierNamespace());
312 
313   // FunctionDecl's body is handled last at ASTWriterDecl::Visit,
314   // after everything else is written.
315 
316   Record.push_back(D->getStorageClass()); // FIXME: stable encoding
317   Record.push_back(D->getStorageClassAsWritten());
318   Record.push_back(D->IsInline);
319   Record.push_back(D->isInlineSpecified());
320   Record.push_back(D->isVirtualAsWritten());
321   Record.push_back(D->isPure());
322   Record.push_back(D->hasInheritedPrototype());
323   Record.push_back(D->hasWrittenPrototype());
324   Record.push_back(D->isDeletedAsWritten());
325   Record.push_back(D->isTrivial());
326   Record.push_back(D->isDefaulted());
327   Record.push_back(D->isExplicitlyDefaulted());
328   Record.push_back(D->hasImplicitReturnZero());
329   Record.push_back(D->isConstexpr());
330   Writer.AddSourceLocation(D->getLocEnd(), Record);
331 
332   Record.push_back(D->getTemplatedKind());
333   switch (D->getTemplatedKind()) {
334   case FunctionDecl::TK_NonTemplate:
335     break;
336   case FunctionDecl::TK_FunctionTemplate:
337     Writer.AddDeclRef(D->getDescribedFunctionTemplate(), Record);
338     break;
339   case FunctionDecl::TK_MemberSpecialization: {
340     MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo();
341     Writer.AddDeclRef(MemberInfo->getInstantiatedFrom(), Record);
342     Record.push_back(MemberInfo->getTemplateSpecializationKind());
343     Writer.AddSourceLocation(MemberInfo->getPointOfInstantiation(), Record);
344     break;
345   }
346   case FunctionDecl::TK_FunctionTemplateSpecialization: {
347     FunctionTemplateSpecializationInfo *
348       FTSInfo = D->getTemplateSpecializationInfo();
349     Writer.AddDeclRef(FTSInfo->getTemplate(), Record);
350     Record.push_back(FTSInfo->getTemplateSpecializationKind());
351 
352     // Template arguments.
353     Writer.AddTemplateArgumentList(FTSInfo->TemplateArguments, Record);
354 
355     // Template args as written.
356     Record.push_back(FTSInfo->TemplateArgumentsAsWritten != 0);
357     if (FTSInfo->TemplateArgumentsAsWritten) {
358       Record.push_back(FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs);
359       for (int i=0, e = FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs;
360              i!=e; ++i)
361         Writer.AddTemplateArgumentLoc((*FTSInfo->TemplateArgumentsAsWritten)[i],
362                                       Record);
363       Writer.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->LAngleLoc,
364                                Record);
365       Writer.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->RAngleLoc,
366                                Record);
367     }
368 
369     Writer.AddSourceLocation(FTSInfo->getPointOfInstantiation(), Record);
370 
371     if (D->isCanonicalDecl()) {
372       // Write the template that contains the specializations set. We will
373       // add a FunctionTemplateSpecializationInfo to it when reading.
374       Writer.AddDeclRef(FTSInfo->getTemplate()->getCanonicalDecl(), Record);
375     }
376     break;
377   }
378   case FunctionDecl::TK_DependentFunctionTemplateSpecialization: {
379     DependentFunctionTemplateSpecializationInfo *
380       DFTSInfo = D->getDependentSpecializationInfo();
381 
382     // Templates.
383     Record.push_back(DFTSInfo->getNumTemplates());
384     for (int i=0, e = DFTSInfo->getNumTemplates(); i != e; ++i)
385       Writer.AddDeclRef(DFTSInfo->getTemplate(i), Record);
386 
387     // Templates args.
388     Record.push_back(DFTSInfo->getNumTemplateArgs());
389     for (int i=0, e = DFTSInfo->getNumTemplateArgs(); i != e; ++i)
390       Writer.AddTemplateArgumentLoc(DFTSInfo->getTemplateArg(i), Record);
391     Writer.AddSourceLocation(DFTSInfo->getLAngleLoc(), Record);
392     Writer.AddSourceLocation(DFTSInfo->getRAngleLoc(), Record);
393     break;
394   }
395   }
396 
397   Record.push_back(D->param_size());
398   for (FunctionDecl::param_iterator P = D->param_begin(), PEnd = D->param_end();
399        P != PEnd; ++P)
400     Writer.AddDeclRef(*P, Record);
401   Code = serialization::DECL_FUNCTION;
402 }
403 
404 void ASTDeclWriter::VisitObjCMethodDecl(ObjCMethodDecl *D) {
405   VisitNamedDecl(D);
406   // FIXME: convert to LazyStmtPtr?
407   // Unlike C/C++, method bodies will never be in header files.
408   bool HasBodyStuff = D->getBody() != 0     ||
409                       D->getSelfDecl() != 0 || D->getCmdDecl() != 0;
410   Record.push_back(HasBodyStuff);
411   if (HasBodyStuff) {
412     Writer.AddStmt(D->getBody());
413     Writer.AddDeclRef(D->getSelfDecl(), Record);
414     Writer.AddDeclRef(D->getCmdDecl(), Record);
415   }
416   Record.push_back(D->isInstanceMethod());
417   Record.push_back(D->isVariadic());
418   Record.push_back(D->isSynthesized());
419   Record.push_back(D->isDefined());
420 
421   Record.push_back(D->IsRedeclaration);
422   Record.push_back(D->HasRedeclaration);
423   if (D->HasRedeclaration) {
424     assert(Context.getObjCMethodRedeclaration(D));
425     Writer.AddDeclRef(Context.getObjCMethodRedeclaration(D), Record);
426   }
427 
428   // FIXME: stable encoding for @required/@optional
429   Record.push_back(D->getImplementationControl());
430   // FIXME: stable encoding for in/out/inout/bycopy/byref/oneway
431   Record.push_back(D->getObjCDeclQualifier());
432   Record.push_back(D->hasRelatedResultType());
433   Writer.AddTypeRef(D->getResultType(), Record);
434   Writer.AddTypeSourceInfo(D->getResultTypeSourceInfo(), Record);
435   Writer.AddSourceLocation(D->getLocEnd(), Record);
436   Record.push_back(D->param_size());
437   for (ObjCMethodDecl::param_iterator P = D->param_begin(),
438                                    PEnd = D->param_end(); P != PEnd; ++P)
439     Writer.AddDeclRef(*P, Record);
440 
441   Record.push_back(D->SelLocsKind);
442   unsigned NumStoredSelLocs = D->getNumStoredSelLocs();
443   SourceLocation *SelLocs = D->getStoredSelLocs();
444   Record.push_back(NumStoredSelLocs);
445   for (unsigned i = 0; i != NumStoredSelLocs; ++i)
446     Writer.AddSourceLocation(SelLocs[i], Record);
447 
448   Code = serialization::DECL_OBJC_METHOD;
449 }
450 
451 void ASTDeclWriter::VisitObjCContainerDecl(ObjCContainerDecl *D) {
452   VisitNamedDecl(D);
453   Writer.AddSourceLocation(D->getAtStartLoc(), Record);
454   Writer.AddSourceRange(D->getAtEndRange(), Record);
455   // Abstract class (no need to define a stable serialization::DECL code).
456 }
457 
458 void ASTDeclWriter::VisitObjCInterfaceDecl(ObjCInterfaceDecl *D) {
459   VisitRedeclarable(D);
460   VisitObjCContainerDecl(D);
461   Writer.AddTypeRef(QualType(D->getTypeForDecl(), 0), Record);
462 
463   Record.push_back(D->isThisDeclarationADefinition());
464   if (D->isThisDeclarationADefinition()) {
465     // Write the DefinitionData
466     ObjCInterfaceDecl::DefinitionData &Data = D->data();
467 
468     Writer.AddDeclRef(D->getSuperClass(), Record);
469     Writer.AddSourceLocation(D->getSuperClassLoc(), Record);
470     Writer.AddSourceLocation(D->getEndOfDefinitionLoc(), Record);
471 
472     // Write out the protocols that are directly referenced by the @interface.
473     Record.push_back(Data.ReferencedProtocols.size());
474     for (ObjCInterfaceDecl::protocol_iterator P = D->protocol_begin(),
475                                            PEnd = D->protocol_end();
476          P != PEnd; ++P)
477       Writer.AddDeclRef(*P, Record);
478     for (ObjCInterfaceDecl::protocol_loc_iterator PL = D->protocol_loc_begin(),
479          PLEnd = D->protocol_loc_end();
480          PL != PLEnd; ++PL)
481       Writer.AddSourceLocation(*PL, Record);
482 
483     // Write out the protocols that are transitively referenced.
484     Record.push_back(Data.AllReferencedProtocols.size());
485     for (ObjCList<ObjCProtocolDecl>::iterator
486               P = Data.AllReferencedProtocols.begin(),
487            PEnd = Data.AllReferencedProtocols.end();
488          P != PEnd; ++P)
489       Writer.AddDeclRef(*P, Record);
490 
491     if (ObjCCategoryDecl *Cat = D->getCategoryList()) {
492       // Ensure that we write out the set of categories for this class.
493       Writer.ObjCClassesWithCategories.insert(D);
494 
495       // Make sure that the categories get serialized.
496       for (; Cat; Cat = Cat->getNextClassCategory())
497         (void)Writer.GetDeclRef(Cat);
498     }
499   }
500 
501   Code = serialization::DECL_OBJC_INTERFACE;
502 }
503 
504 void ASTDeclWriter::VisitObjCIvarDecl(ObjCIvarDecl *D) {
505   VisitFieldDecl(D);
506   // FIXME: stable encoding for @public/@private/@protected/@package
507   Record.push_back(D->getAccessControl());
508   Record.push_back(D->getSynthesize());
509 
510   if (!D->hasAttrs() &&
511       !D->isImplicit() &&
512       !D->isUsed(false) &&
513       !D->isInvalidDecl() &&
514       !D->isReferenced() &&
515       !D->isModulePrivate() &&
516       !D->getBitWidth() &&
517       !D->hasExtInfo() &&
518       D->getDeclName())
519     AbbrevToUse = Writer.getDeclObjCIvarAbbrev();
520 
521   Code = serialization::DECL_OBJC_IVAR;
522 }
523 
524 void ASTDeclWriter::VisitObjCProtocolDecl(ObjCProtocolDecl *D) {
525   VisitRedeclarable(D);
526   VisitObjCContainerDecl(D);
527 
528   Record.push_back(D->isThisDeclarationADefinition());
529   if (D->isThisDeclarationADefinition()) {
530     Record.push_back(D->protocol_size());
531     for (ObjCProtocolDecl::protocol_iterator
532          I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
533       Writer.AddDeclRef(*I, Record);
534     for (ObjCProtocolDecl::protocol_loc_iterator PL = D->protocol_loc_begin(),
535            PLEnd = D->protocol_loc_end();
536          PL != PLEnd; ++PL)
537       Writer.AddSourceLocation(*PL, Record);
538   }
539 
540   Code = serialization::DECL_OBJC_PROTOCOL;
541 }
542 
543 void ASTDeclWriter::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D) {
544   VisitFieldDecl(D);
545   Code = serialization::DECL_OBJC_AT_DEFS_FIELD;
546 }
547 
548 void ASTDeclWriter::VisitObjCCategoryDecl(ObjCCategoryDecl *D) {
549   VisitObjCContainerDecl(D);
550   Writer.AddSourceLocation(D->getCategoryNameLoc(), Record);
551   Writer.AddSourceLocation(D->getIvarLBraceLoc(), Record);
552   Writer.AddSourceLocation(D->getIvarRBraceLoc(), Record);
553   Writer.AddDeclRef(D->getClassInterface(), Record);
554   Record.push_back(D->protocol_size());
555   for (ObjCCategoryDecl::protocol_iterator
556        I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
557     Writer.AddDeclRef(*I, Record);
558   for (ObjCCategoryDecl::protocol_loc_iterator
559          PL = D->protocol_loc_begin(), PLEnd = D->protocol_loc_end();
560        PL != PLEnd; ++PL)
561     Writer.AddSourceLocation(*PL, Record);
562   Record.push_back(D->hasSynthBitfield());
563   Code = serialization::DECL_OBJC_CATEGORY;
564 }
565 
566 void ASTDeclWriter::VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D) {
567   VisitNamedDecl(D);
568   Writer.AddDeclRef(D->getClassInterface(), Record);
569   Code = serialization::DECL_OBJC_COMPATIBLE_ALIAS;
570 }
571 
572 void ASTDeclWriter::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
573   VisitNamedDecl(D);
574   Writer.AddSourceLocation(D->getAtLoc(), Record);
575   Writer.AddSourceLocation(D->getLParenLoc(), Record);
576   Writer.AddTypeSourceInfo(D->getTypeSourceInfo(), Record);
577   // FIXME: stable encoding
578   Record.push_back((unsigned)D->getPropertyAttributes());
579   Record.push_back((unsigned)D->getPropertyAttributesAsWritten());
580   // FIXME: stable encoding
581   Record.push_back((unsigned)D->getPropertyImplementation());
582   Writer.AddDeclarationName(D->getGetterName(), Record);
583   Writer.AddDeclarationName(D->getSetterName(), Record);
584   Writer.AddDeclRef(D->getGetterMethodDecl(), Record);
585   Writer.AddDeclRef(D->getSetterMethodDecl(), Record);
586   Writer.AddDeclRef(D->getPropertyIvarDecl(), Record);
587   Code = serialization::DECL_OBJC_PROPERTY;
588 }
589 
590 void ASTDeclWriter::VisitObjCImplDecl(ObjCImplDecl *D) {
591   VisitObjCContainerDecl(D);
592   Writer.AddDeclRef(D->getClassInterface(), Record);
593   // Abstract class (no need to define a stable serialization::DECL code).
594 }
595 
596 void ASTDeclWriter::VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D) {
597   VisitObjCImplDecl(D);
598   Writer.AddIdentifierRef(D->getIdentifier(), Record);
599   Writer.AddSourceLocation(D->getCategoryNameLoc(), Record);
600   Code = serialization::DECL_OBJC_CATEGORY_IMPL;
601 }
602 
603 void ASTDeclWriter::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
604   VisitObjCImplDecl(D);
605   Writer.AddDeclRef(D->getSuperClass(), Record);
606   Writer.AddSourceLocation(D->getIvarLBraceLoc(), Record);
607   Writer.AddSourceLocation(D->getIvarRBraceLoc(), Record);
608   Writer.AddCXXCtorInitializers(D->IvarInitializers, D->NumIvarInitializers,
609                                 Record);
610   Record.push_back(D->hasSynthBitfield());
611   Code = serialization::DECL_OBJC_IMPLEMENTATION;
612 }
613 
614 void ASTDeclWriter::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
615   VisitDecl(D);
616   Writer.AddSourceLocation(D->getLocStart(), Record);
617   Writer.AddDeclRef(D->getPropertyDecl(), Record);
618   Writer.AddDeclRef(D->getPropertyIvarDecl(), Record);
619   Writer.AddSourceLocation(D->getPropertyIvarDeclLoc(), Record);
620   Writer.AddStmt(D->getGetterCXXConstructor());
621   Writer.AddStmt(D->getSetterCXXAssignment());
622   Code = serialization::DECL_OBJC_PROPERTY_IMPL;
623 }
624 
625 void ASTDeclWriter::VisitFieldDecl(FieldDecl *D) {
626   VisitDeclaratorDecl(D);
627   Record.push_back(D->isMutable());
628   Record.push_back(D->getBitWidth()? 1 : D->hasInClassInitializer() ? 2 : 0);
629   if (D->getBitWidth())
630     Writer.AddStmt(D->getBitWidth());
631   else if (D->hasInClassInitializer())
632     Writer.AddStmt(D->getInClassInitializer());
633   if (!D->getDeclName())
634     Writer.AddDeclRef(Context.getInstantiatedFromUnnamedFieldDecl(D), Record);
635 
636   if (!D->hasAttrs() &&
637       !D->isImplicit() &&
638       !D->isUsed(false) &&
639       !D->isInvalidDecl() &&
640       !D->isReferenced() &&
641       !D->isTopLevelDeclInObjCContainer() &&
642       !D->isModulePrivate() &&
643       !D->getBitWidth() &&
644       !D->hasInClassInitializer() &&
645       !D->hasExtInfo() &&
646       !ObjCIvarDecl::classofKind(D->getKind()) &&
647       !ObjCAtDefsFieldDecl::classofKind(D->getKind()) &&
648       D->getDeclName())
649     AbbrevToUse = Writer.getDeclFieldAbbrev();
650 
651   Code = serialization::DECL_FIELD;
652 }
653 
654 void ASTDeclWriter::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
655   VisitValueDecl(D);
656   Record.push_back(D->getChainingSize());
657 
658   for (IndirectFieldDecl::chain_iterator
659        P = D->chain_begin(),
660        PEnd = D->chain_end(); P != PEnd; ++P)
661     Writer.AddDeclRef(*P, Record);
662   Code = serialization::DECL_INDIRECTFIELD;
663 }
664 
665 void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
666   VisitRedeclarable(D);
667   VisitDeclaratorDecl(D);
668   Record.push_back(D->getStorageClass()); // FIXME: stable encoding
669   Record.push_back(D->getStorageClassAsWritten());
670   Record.push_back(D->isThreadSpecified());
671   Record.push_back(D->getInitStyle());
672   Record.push_back(D->isExceptionVariable());
673   Record.push_back(D->isNRVOVariable());
674   Record.push_back(D->isCXXForRangeDecl());
675   Record.push_back(D->isARCPseudoStrong());
676   if (D->getInit()) {
677     Record.push_back(!D->isInitKnownICE() ? 1 : (D->isInitICE() ? 3 : 2));
678     Writer.AddStmt(D->getInit());
679   } else {
680     Record.push_back(0);
681   }
682 
683   MemberSpecializationInfo *SpecInfo
684     = D->isStaticDataMember() ? D->getMemberSpecializationInfo() : 0;
685   Record.push_back(SpecInfo != 0);
686   if (SpecInfo) {
687     Writer.AddDeclRef(SpecInfo->getInstantiatedFrom(), Record);
688     Record.push_back(SpecInfo->getTemplateSpecializationKind());
689     Writer.AddSourceLocation(SpecInfo->getPointOfInstantiation(), Record);
690   }
691 
692   if (!D->hasAttrs() &&
693       !D->isImplicit() &&
694       !D->isUsed(false) &&
695       !D->isInvalidDecl() &&
696       !D->isReferenced() &&
697       !D->isTopLevelDeclInObjCContainer() &&
698       D->getAccess() == AS_none &&
699       !D->isModulePrivate() &&
700       D->getDeclName().getNameKind() == DeclarationName::Identifier &&
701       !D->hasExtInfo() &&
702       D->getFirstDeclaration() == D->getMostRecentDecl() &&
703       D->getInitStyle() == VarDecl::CInit &&
704       D->getInit() == 0 &&
705       !isa<ParmVarDecl>(D) &&
706       !SpecInfo)
707     AbbrevToUse = Writer.getDeclVarAbbrev();
708 
709   Code = serialization::DECL_VAR;
710 }
711 
712 void ASTDeclWriter::VisitImplicitParamDecl(ImplicitParamDecl *D) {
713   VisitVarDecl(D);
714   Code = serialization::DECL_IMPLICIT_PARAM;
715 }
716 
717 void ASTDeclWriter::VisitParmVarDecl(ParmVarDecl *D) {
718   VisitVarDecl(D);
719   Record.push_back(D->isObjCMethodParameter());
720   Record.push_back(D->getFunctionScopeDepth());
721   Record.push_back(D->getFunctionScopeIndex());
722   Record.push_back(D->getObjCDeclQualifier()); // FIXME: stable encoding
723   Record.push_back(D->isKNRPromoted());
724   Record.push_back(D->hasInheritedDefaultArg());
725   Record.push_back(D->hasUninstantiatedDefaultArg());
726   if (D->hasUninstantiatedDefaultArg())
727     Writer.AddStmt(D->getUninstantiatedDefaultArg());
728   Code = serialization::DECL_PARM_VAR;
729 
730   assert(!D->isARCPseudoStrong()); // can be true of ImplicitParamDecl
731 
732   // If the assumptions about the DECL_PARM_VAR abbrev are true, use it.  Here
733   // we dynamically check for the properties that we optimize for, but don't
734   // know are true of all PARM_VAR_DECLs.
735   if (!D->hasAttrs() &&
736       !D->hasExtInfo() &&
737       !D->isImplicit() &&
738       !D->isUsed(false) &&
739       !D->isInvalidDecl() &&
740       !D->isReferenced() &&
741       D->getAccess() == AS_none &&
742       !D->isModulePrivate() &&
743       D->getStorageClass() == 0 &&
744       D->getInitStyle() == VarDecl::CInit && // Can params have anything else?
745       D->getFunctionScopeDepth() == 0 &&
746       D->getObjCDeclQualifier() == 0 &&
747       !D->isKNRPromoted() &&
748       !D->hasInheritedDefaultArg() &&
749       D->getInit() == 0 &&
750       !D->hasUninstantiatedDefaultArg())  // No default expr.
751     AbbrevToUse = Writer.getDeclParmVarAbbrev();
752 
753   // Check things we know are true of *every* PARM_VAR_DECL, which is more than
754   // just us assuming it.
755   assert(!D->isThreadSpecified() && "PARM_VAR_DECL can't be __thread");
756   assert(D->getAccess() == AS_none && "PARM_VAR_DECL can't be public/private");
757   assert(!D->isExceptionVariable() && "PARM_VAR_DECL can't be exception var");
758   assert(D->getPreviousDecl() == 0 && "PARM_VAR_DECL can't be redecl");
759   assert(!D->isStaticDataMember() &&
760          "PARM_VAR_DECL can't be static data member");
761 }
762 
763 void ASTDeclWriter::VisitFileScopeAsmDecl(FileScopeAsmDecl *D) {
764   VisitDecl(D);
765   Writer.AddStmt(D->getAsmString());
766   Writer.AddSourceLocation(D->getRParenLoc(), Record);
767   Code = serialization::DECL_FILE_SCOPE_ASM;
768 }
769 
770 void ASTDeclWriter::VisitBlockDecl(BlockDecl *D) {
771   VisitDecl(D);
772   Writer.AddStmt(D->getBody());
773   Writer.AddTypeSourceInfo(D->getSignatureAsWritten(), Record);
774   Record.push_back(D->param_size());
775   for (FunctionDecl::param_iterator P = D->param_begin(), PEnd = D->param_end();
776        P != PEnd; ++P)
777     Writer.AddDeclRef(*P, Record);
778   Record.push_back(D->capturesCXXThis());
779   Record.push_back(D->getNumCaptures());
780   for (BlockDecl::capture_iterator
781          i = D->capture_begin(), e = D->capture_end(); i != e; ++i) {
782     const BlockDecl::Capture &capture = *i;
783     Writer.AddDeclRef(capture.getVariable(), Record);
784 
785     unsigned flags = 0;
786     if (capture.isByRef()) flags |= 1;
787     if (capture.isNested()) flags |= 2;
788     if (capture.hasCopyExpr()) flags |= 4;
789     Record.push_back(flags);
790 
791     if (capture.hasCopyExpr()) Writer.AddStmt(capture.getCopyExpr());
792   }
793 
794   Code = serialization::DECL_BLOCK;
795 }
796 
797 void ASTDeclWriter::VisitLinkageSpecDecl(LinkageSpecDecl *D) {
798   VisitDecl(D);
799   Record.push_back(D->getLanguage());
800   Writer.AddSourceLocation(D->getExternLoc(), Record);
801   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
802   Code = serialization::DECL_LINKAGE_SPEC;
803 }
804 
805 void ASTDeclWriter::VisitLabelDecl(LabelDecl *D) {
806   VisitNamedDecl(D);
807   Writer.AddSourceLocation(D->getLocStart(), Record);
808   Code = serialization::DECL_LABEL;
809 }
810 
811 
812 void ASTDeclWriter::VisitNamespaceDecl(NamespaceDecl *D) {
813   VisitRedeclarable(D);
814   VisitNamedDecl(D);
815   Record.push_back(D->isInline());
816   Writer.AddSourceLocation(D->getLocStart(), Record);
817   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
818 
819   if (D->isOriginalNamespace())
820     Writer.AddDeclRef(D->getAnonymousNamespace(), Record);
821   Code = serialization::DECL_NAMESPACE;
822 
823   if (Writer.hasChain() && !D->isOriginalNamespace() &&
824       D->getOriginalNamespace()->isFromASTFile()) {
825     NamespaceDecl *NS = D->getOriginalNamespace();
826     Writer.AddUpdatedDeclContext(NS);
827 
828     // Make sure all visible decls are written. They will be recorded later.
829     if (StoredDeclsMap *Map = NS->buildLookup()) {
830       for (StoredDeclsMap::iterator D = Map->begin(), DEnd = Map->end();
831            D != DEnd; ++D) {
832         DeclContext::lookup_result Result = D->second.getLookupResult();
833         while (Result.first != Result.second) {
834           Writer.GetDeclRef(*Result.first);
835           ++Result.first;
836         }
837       }
838     }
839   }
840 
841   if (Writer.hasChain() && D->isAnonymousNamespace() &&
842       D == D->getMostRecentDecl()) {
843     // This is a most recent reopening of the anonymous namespace. If its parent
844     // is in a previous PCH (or is the TU), mark that parent for update, because
845     // the original namespace always points to the latest re-opening of its
846     // anonymous namespace.
847     Decl *Parent = cast<Decl>(
848         D->getParent()->getRedeclContext()->getPrimaryContext());
849     if (Parent->isFromASTFile() || isa<TranslationUnitDecl>(Parent)) {
850       ASTWriter::UpdateRecord &Record = Writer.DeclUpdates[Parent];
851       Record.push_back(UPD_CXX_ADDED_ANONYMOUS_NAMESPACE);
852       Writer.AddDeclRef(D, Record);
853     }
854   }
855 }
856 
857 void ASTDeclWriter::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
858   VisitNamedDecl(D);
859   Writer.AddSourceLocation(D->getNamespaceLoc(), Record);
860   Writer.AddSourceLocation(D->getTargetNameLoc(), Record);
861   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
862   Writer.AddDeclRef(D->getNamespace(), Record);
863   Code = serialization::DECL_NAMESPACE_ALIAS;
864 }
865 
866 void ASTDeclWriter::VisitUsingDecl(UsingDecl *D) {
867   VisitNamedDecl(D);
868   Writer.AddSourceLocation(D->getUsingLocation(), Record);
869   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
870   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
871   Writer.AddDeclRef(D->FirstUsingShadow.getPointer(), Record);
872   Record.push_back(D->isTypeName());
873   Writer.AddDeclRef(Context.getInstantiatedFromUsingDecl(D), Record);
874   Code = serialization::DECL_USING;
875 }
876 
877 void ASTDeclWriter::VisitUsingShadowDecl(UsingShadowDecl *D) {
878   VisitNamedDecl(D);
879   Writer.AddDeclRef(D->getTargetDecl(), Record);
880   Writer.AddDeclRef(D->UsingOrNextShadow, Record);
881   Writer.AddDeclRef(Context.getInstantiatedFromUsingShadowDecl(D), Record);
882   Code = serialization::DECL_USING_SHADOW;
883 }
884 
885 void ASTDeclWriter::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
886   VisitNamedDecl(D);
887   Writer.AddSourceLocation(D->getUsingLoc(), Record);
888   Writer.AddSourceLocation(D->getNamespaceKeyLocation(), Record);
889   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
890   Writer.AddDeclRef(D->getNominatedNamespace(), Record);
891   Writer.AddDeclRef(dyn_cast<Decl>(D->getCommonAncestor()), Record);
892   Code = serialization::DECL_USING_DIRECTIVE;
893 }
894 
895 void ASTDeclWriter::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
896   VisitValueDecl(D);
897   Writer.AddSourceLocation(D->getUsingLoc(), Record);
898   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
899   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
900   Code = serialization::DECL_UNRESOLVED_USING_VALUE;
901 }
902 
903 void ASTDeclWriter::VisitUnresolvedUsingTypenameDecl(
904                                                UnresolvedUsingTypenameDecl *D) {
905   VisitTypeDecl(D);
906   Writer.AddSourceLocation(D->getTypenameLoc(), Record);
907   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
908   Code = serialization::DECL_UNRESOLVED_USING_TYPENAME;
909 }
910 
911 void ASTDeclWriter::VisitCXXRecordDecl(CXXRecordDecl *D) {
912   VisitRecordDecl(D);
913   Record.push_back(D->isThisDeclarationADefinition());
914   if (D->isThisDeclarationADefinition())
915     Writer.AddCXXDefinitionData(D, Record);
916 
917   enum {
918     CXXRecNotTemplate = 0, CXXRecTemplate, CXXRecMemberSpecialization
919   };
920   if (ClassTemplateDecl *TemplD = D->getDescribedClassTemplate()) {
921     Record.push_back(CXXRecTemplate);
922     Writer.AddDeclRef(TemplD, Record);
923   } else if (MemberSpecializationInfo *MSInfo
924                = D->getMemberSpecializationInfo()) {
925     Record.push_back(CXXRecMemberSpecialization);
926     Writer.AddDeclRef(MSInfo->getInstantiatedFrom(), Record);
927     Record.push_back(MSInfo->getTemplateSpecializationKind());
928     Writer.AddSourceLocation(MSInfo->getPointOfInstantiation(), Record);
929   } else {
930     Record.push_back(CXXRecNotTemplate);
931   }
932 
933   // Store the key function to avoid deserializing every method so we can
934   // compute it.
935   if (D->IsCompleteDefinition)
936     Writer.AddDeclRef(Context.getKeyFunction(D), Record);
937 
938   Code = serialization::DECL_CXX_RECORD;
939 }
940 
941 void ASTDeclWriter::VisitCXXMethodDecl(CXXMethodDecl *D) {
942   VisitFunctionDecl(D);
943   Record.push_back(D->size_overridden_methods());
944   for (CXXMethodDecl::method_iterator
945          I = D->begin_overridden_methods(), E = D->end_overridden_methods();
946          I != E; ++I)
947     Writer.AddDeclRef(*I, Record);
948   Code = serialization::DECL_CXX_METHOD;
949 }
950 
951 void ASTDeclWriter::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
952   VisitCXXMethodDecl(D);
953 
954   Record.push_back(D->IsExplicitSpecified);
955   Record.push_back(D->ImplicitlyDefined);
956   Writer.AddCXXCtorInitializers(D->CtorInitializers, D->NumCtorInitializers,
957                                 Record);
958 
959   Code = serialization::DECL_CXX_CONSTRUCTOR;
960 }
961 
962 void ASTDeclWriter::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
963   VisitCXXMethodDecl(D);
964 
965   Record.push_back(D->ImplicitlyDefined);
966   Writer.AddDeclRef(D->OperatorDelete, Record);
967 
968   Code = serialization::DECL_CXX_DESTRUCTOR;
969 }
970 
971 void ASTDeclWriter::VisitCXXConversionDecl(CXXConversionDecl *D) {
972   VisitCXXMethodDecl(D);
973   Record.push_back(D->IsExplicitSpecified);
974   Code = serialization::DECL_CXX_CONVERSION;
975 }
976 
977 void ASTDeclWriter::VisitImportDecl(ImportDecl *D) {
978   VisitDecl(D);
979   ArrayRef<SourceLocation> IdentifierLocs = D->getIdentifierLocs();
980   Record.push_back(!IdentifierLocs.empty());
981   if (IdentifierLocs.empty()) {
982     Writer.AddSourceLocation(D->getLocEnd(), Record);
983     Record.push_back(1);
984   } else {
985     for (unsigned I = 0, N = IdentifierLocs.size(); I != N; ++I)
986       Writer.AddSourceLocation(IdentifierLocs[I], Record);
987     Record.push_back(IdentifierLocs.size());
988   }
989   // Note: the number of source locations must always be the last element in
990   // the record.
991   Code = serialization::DECL_IMPORT;
992 }
993 
994 void ASTDeclWriter::VisitAccessSpecDecl(AccessSpecDecl *D) {
995   VisitDecl(D);
996   Writer.AddSourceLocation(D->getColonLoc(), Record);
997   Code = serialization::DECL_ACCESS_SPEC;
998 }
999 
1000 void ASTDeclWriter::VisitFriendDecl(FriendDecl *D) {
1001   VisitDecl(D);
1002   Record.push_back(D->Friend.is<TypeSourceInfo*>());
1003   if (D->Friend.is<TypeSourceInfo*>())
1004     Writer.AddTypeSourceInfo(D->Friend.get<TypeSourceInfo*>(), Record);
1005   else
1006     Writer.AddDeclRef(D->Friend.get<NamedDecl*>(), Record);
1007   Writer.AddDeclRef(D->getNextFriend(), Record);
1008   Record.push_back(D->UnsupportedFriend);
1009   Writer.AddSourceLocation(D->FriendLoc, Record);
1010   Code = serialization::DECL_FRIEND;
1011 }
1012 
1013 void ASTDeclWriter::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
1014   VisitDecl(D);
1015   Record.push_back(D->getNumTemplateParameters());
1016   for (unsigned i = 0, e = D->getNumTemplateParameters(); i != e; ++i)
1017     Writer.AddTemplateParameterList(D->getTemplateParameterList(i), Record);
1018   Record.push_back(D->getFriendDecl() != 0);
1019   if (D->getFriendDecl())
1020     Writer.AddDeclRef(D->getFriendDecl(), Record);
1021   else
1022     Writer.AddTypeSourceInfo(D->getFriendType(), Record);
1023   Writer.AddSourceLocation(D->getFriendLoc(), Record);
1024   Code = serialization::DECL_FRIEND_TEMPLATE;
1025 }
1026 
1027 void ASTDeclWriter::VisitTemplateDecl(TemplateDecl *D) {
1028   VisitNamedDecl(D);
1029 
1030   Writer.AddDeclRef(D->getTemplatedDecl(), Record);
1031   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
1032 }
1033 
1034 void ASTDeclWriter::VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D) {
1035   VisitRedeclarable(D);
1036 
1037   // Emit data to initialize CommonOrPrev before VisitTemplateDecl so that
1038   // getCommonPtr() can be used while this is still initializing.
1039   if (D->isFirstDeclaration()) {
1040     // This declaration owns the 'common' pointer, so serialize that data now.
1041     Writer.AddDeclRef(D->getInstantiatedFromMemberTemplate(), Record);
1042     if (D->getInstantiatedFromMemberTemplate())
1043       Record.push_back(D->isMemberSpecialization());
1044   }
1045 
1046   VisitTemplateDecl(D);
1047   Record.push_back(D->getIdentifierNamespace());
1048 }
1049 
1050 void ASTDeclWriter::VisitClassTemplateDecl(ClassTemplateDecl *D) {
1051   VisitRedeclarableTemplateDecl(D);
1052 
1053   if (D->isFirstDeclaration()) {
1054     typedef llvm::FoldingSet<ClassTemplateSpecializationDecl> CTSDSetTy;
1055     CTSDSetTy &CTSDSet = D->getSpecializations();
1056     Record.push_back(CTSDSet.size());
1057     for (CTSDSetTy::iterator I=CTSDSet.begin(), E = CTSDSet.end(); I!=E; ++I) {
1058       assert(I->isCanonicalDecl() && "Expected only canonical decls in set");
1059       Writer.AddDeclRef(&*I, Record);
1060     }
1061 
1062     typedef llvm::FoldingSet<ClassTemplatePartialSpecializationDecl> CTPSDSetTy;
1063     CTPSDSetTy &CTPSDSet = D->getPartialSpecializations();
1064     Record.push_back(CTPSDSet.size());
1065     for (CTPSDSetTy::iterator I=CTPSDSet.begin(), E=CTPSDSet.end(); I!=E; ++I) {
1066       assert(I->isCanonicalDecl() && "Expected only canonical decls in set");
1067       Writer.AddDeclRef(&*I, Record);
1068     }
1069 
1070     // InjectedClassNameType is computed, no need to write it.
1071   }
1072   Code = serialization::DECL_CLASS_TEMPLATE;
1073 }
1074 
1075 void ASTDeclWriter::VisitClassTemplateSpecializationDecl(
1076                                            ClassTemplateSpecializationDecl *D) {
1077   VisitCXXRecordDecl(D);
1078 
1079   llvm::PointerUnion<ClassTemplateDecl *,
1080                      ClassTemplatePartialSpecializationDecl *> InstFrom
1081     = D->getSpecializedTemplateOrPartial();
1082   if (Decl *InstFromD = InstFrom.dyn_cast<ClassTemplateDecl *>()) {
1083     Writer.AddDeclRef(InstFromD, Record);
1084   } else {
1085     Writer.AddDeclRef(InstFrom.get<ClassTemplatePartialSpecializationDecl *>(),
1086                       Record);
1087     Writer.AddTemplateArgumentList(&D->getTemplateInstantiationArgs(), Record);
1088   }
1089 
1090   // Explicit info.
1091   Writer.AddTypeSourceInfo(D->getTypeAsWritten(), Record);
1092   if (D->getTypeAsWritten()) {
1093     Writer.AddSourceLocation(D->getExternLoc(), Record);
1094     Writer.AddSourceLocation(D->getTemplateKeywordLoc(), Record);
1095   }
1096 
1097   Writer.AddTemplateArgumentList(&D->getTemplateArgs(), Record);
1098   Writer.AddSourceLocation(D->getPointOfInstantiation(), Record);
1099   Record.push_back(D->getSpecializationKind());
1100 
1101   if (D->isCanonicalDecl()) {
1102     // When reading, we'll add it to the folding set of the following template.
1103     Writer.AddDeclRef(D->getSpecializedTemplate()->getCanonicalDecl(), Record);
1104   }
1105 
1106   Code = serialization::DECL_CLASS_TEMPLATE_SPECIALIZATION;
1107 }
1108 
1109 void ASTDeclWriter::VisitClassTemplatePartialSpecializationDecl(
1110                                     ClassTemplatePartialSpecializationDecl *D) {
1111   VisitClassTemplateSpecializationDecl(D);
1112 
1113   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
1114 
1115   Record.push_back(D->getNumTemplateArgsAsWritten());
1116   for (int i = 0, e = D->getNumTemplateArgsAsWritten(); i != e; ++i)
1117     Writer.AddTemplateArgumentLoc(D->getTemplateArgsAsWritten()[i], Record);
1118 
1119   Record.push_back(D->getSequenceNumber());
1120 
1121   // These are read/set from/to the first declaration.
1122   if (D->getPreviousDecl() == 0) {
1123     Writer.AddDeclRef(D->getInstantiatedFromMember(), Record);
1124     Record.push_back(D->isMemberSpecialization());
1125   }
1126 
1127   Code = serialization::DECL_CLASS_TEMPLATE_PARTIAL_SPECIALIZATION;
1128 }
1129 
1130 void ASTDeclWriter::VisitClassScopeFunctionSpecializationDecl(
1131                                     ClassScopeFunctionSpecializationDecl *D) {
1132   VisitDecl(D);
1133   Writer.AddDeclRef(D->getSpecialization(), Record);
1134   Code = serialization::DECL_CLASS_SCOPE_FUNCTION_SPECIALIZATION;
1135 }
1136 
1137 
1138 void ASTDeclWriter::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
1139   VisitRedeclarableTemplateDecl(D);
1140 
1141   if (D->isFirstDeclaration()) {
1142     // This FunctionTemplateDecl owns the CommonPtr; write it.
1143 
1144     // Write the function specialization declarations.
1145     Record.push_back(D->getSpecializations().size());
1146     for (llvm::FoldingSet<FunctionTemplateSpecializationInfo>::iterator
1147            I = D->getSpecializations().begin(),
1148            E = D->getSpecializations().end()   ; I != E; ++I) {
1149       assert(I->Function->isCanonicalDecl() &&
1150              "Expected only canonical decls in set");
1151       Writer.AddDeclRef(I->Function, Record);
1152     }
1153   }
1154   Code = serialization::DECL_FUNCTION_TEMPLATE;
1155 }
1156 
1157 void ASTDeclWriter::VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D) {
1158   VisitTypeDecl(D);
1159 
1160   Record.push_back(D->wasDeclaredWithTypename());
1161   Record.push_back(D->defaultArgumentWasInherited());
1162   Writer.AddTypeSourceInfo(D->getDefaultArgumentInfo(), Record);
1163 
1164   Code = serialization::DECL_TEMPLATE_TYPE_PARM;
1165 }
1166 
1167 void ASTDeclWriter::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
1168   // For an expanded parameter pack, record the number of expansion types here
1169   // so that it's easier for
1170   if (D->isExpandedParameterPack())
1171     Record.push_back(D->getNumExpansionTypes());
1172 
1173   VisitDeclaratorDecl(D);
1174   // TemplateParmPosition.
1175   Record.push_back(D->getDepth());
1176   Record.push_back(D->getPosition());
1177 
1178   if (D->isExpandedParameterPack()) {
1179     for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
1180       Writer.AddTypeRef(D->getExpansionType(I), Record);
1181       Writer.AddTypeSourceInfo(D->getExpansionTypeSourceInfo(I), Record);
1182     }
1183 
1184     Code = serialization::DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK;
1185   } else {
1186     // Rest of NonTypeTemplateParmDecl.
1187     Record.push_back(D->isParameterPack());
1188     Record.push_back(D->getDefaultArgument() != 0);
1189     if (D->getDefaultArgument()) {
1190       Writer.AddStmt(D->getDefaultArgument());
1191       Record.push_back(D->defaultArgumentWasInherited());
1192     }
1193     Code = serialization::DECL_NON_TYPE_TEMPLATE_PARM;
1194   }
1195 }
1196 
1197 void ASTDeclWriter::VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D) {
1198   VisitTemplateDecl(D);
1199   // TemplateParmPosition.
1200   Record.push_back(D->getDepth());
1201   Record.push_back(D->getPosition());
1202   // Rest of TemplateTemplateParmDecl.
1203   Writer.AddTemplateArgumentLoc(D->getDefaultArgument(), Record);
1204   Record.push_back(D->defaultArgumentWasInherited());
1205   Record.push_back(D->isParameterPack());
1206   Code = serialization::DECL_TEMPLATE_TEMPLATE_PARM;
1207 }
1208 
1209 void ASTDeclWriter::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
1210   VisitRedeclarableTemplateDecl(D);
1211   Code = serialization::DECL_TYPE_ALIAS_TEMPLATE;
1212 }
1213 
1214 void ASTDeclWriter::VisitStaticAssertDecl(StaticAssertDecl *D) {
1215   VisitDecl(D);
1216   Writer.AddStmt(D->getAssertExpr());
1217   Writer.AddStmt(D->getMessage());
1218   Writer.AddSourceLocation(D->getRParenLoc(), Record);
1219   Code = serialization::DECL_STATIC_ASSERT;
1220 }
1221 
1222 /// \brief Emit the DeclContext part of a declaration context decl.
1223 ///
1224 /// \param LexicalOffset the offset at which the DECL_CONTEXT_LEXICAL
1225 /// block for this declaration context is stored. May be 0 to indicate
1226 /// that there are no declarations stored within this context.
1227 ///
1228 /// \param VisibleOffset the offset at which the DECL_CONTEXT_VISIBLE
1229 /// block for this declaration context is stored. May be 0 to indicate
1230 /// that there are no declarations visible from this context. Note
1231 /// that this value will not be emitted for non-primary declaration
1232 /// contexts.
1233 void ASTDeclWriter::VisitDeclContext(DeclContext *DC, uint64_t LexicalOffset,
1234                                      uint64_t VisibleOffset) {
1235   Record.push_back(LexicalOffset);
1236   Record.push_back(VisibleOffset);
1237 }
1238 
1239 template <typename T>
1240 void ASTDeclWriter::VisitRedeclarable(Redeclarable<T> *D) {
1241   T *First = D->getFirstDeclaration();
1242   if (First->getMostRecentDecl() != First) {
1243     // There is more than one declaration of this entity, so we will need to
1244     // write a redeclaration chain.
1245     Writer.AddDeclRef(First, Record);
1246     Writer.Redeclarations.insert(First);
1247 
1248     // Make sure that we serialize both the previous and the most-recent
1249     // declarations, which (transitively) ensures that all declarations in the
1250     // chain get serialized.
1251     (void)Writer.GetDeclRef(D->getPreviousDecl());
1252     (void)Writer.GetDeclRef(First->getMostRecentDecl());
1253   } else {
1254     // We use the sentinel value 0 to indicate an only declaration.
1255     Record.push_back(0);
1256   }
1257 
1258 }
1259 
1260 //===----------------------------------------------------------------------===//
1261 // ASTWriter Implementation
1262 //===----------------------------------------------------------------------===//
1263 
1264 void ASTWriter::WriteDeclsBlockAbbrevs() {
1265   using namespace llvm;
1266 
1267   BitCodeAbbrev *Abv;
1268 
1269   // Abbreviation for DECL_FIELD
1270   Abv = new BitCodeAbbrev();
1271   Abv->Add(BitCodeAbbrevOp(serialization::DECL_FIELD));
1272   // Decl
1273   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1274   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1275   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1276   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1277   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1278   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1279   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1280   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1281   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1282   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1283   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1284   // NamedDecl
1285   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1286   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1287   // ValueDecl
1288   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1289   // DeclaratorDecl
1290   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1291   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1292   // FieldDecl
1293   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1294   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1295   // Type Source Info
1296   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1297   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1298   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1299   DeclFieldAbbrev = Stream.EmitAbbrev(Abv);
1300 
1301   // Abbreviation for DECL_OBJC_IVAR
1302   Abv = new BitCodeAbbrev();
1303   Abv->Add(BitCodeAbbrevOp(serialization::DECL_OBJC_IVAR));
1304   // Decl
1305   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1306   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1307   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1308   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1309   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1310   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1311   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1312   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1313   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1314   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1315   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1316   // NamedDecl
1317   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1318   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1319   // ValueDecl
1320   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1321   // DeclaratorDecl
1322   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1323   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1324   // FieldDecl
1325   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1326   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1327   // ObjC Ivar
1328   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getAccessControl
1329   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getSynthesize
1330   // Type Source Info
1331   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1332   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1333   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1334   DeclObjCIvarAbbrev = Stream.EmitAbbrev(Abv);
1335 
1336   // Abbreviation for DECL_ENUM
1337   Abv = new BitCodeAbbrev();
1338   Abv->Add(BitCodeAbbrevOp(serialization::DECL_ENUM));
1339   // Redeclarable
1340   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1341   // Decl
1342   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1343   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1344   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1345   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1346   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1347   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1348   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1349   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1350   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1351   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1352   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1353   // NamedDecl
1354   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1355   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1356   // TypeDecl
1357   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1358   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1359   // TagDecl
1360   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1361   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1362   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1363   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1364   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1365   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1366   Abv->Add(BitCodeAbbrevOp(0));                         // hasExtInfo
1367   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // TypedefNameAnonDecl
1368   // EnumDecl
1369   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // AddTypeRef
1370   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IntegerType
1371   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getPromotionType
1372   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumPositiveBits
1373   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumNegativeBits
1374   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScoped
1375   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScopedUsingClassTag
1376   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isFixed
1377   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // InstantiatedMembEnum
1378   // DC
1379   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1380   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1381   DeclEnumAbbrev = Stream.EmitAbbrev(Abv);
1382 
1383   // Abbreviation for DECL_RECORD
1384   Abv = new BitCodeAbbrev();
1385   Abv->Add(BitCodeAbbrevOp(serialization::DECL_RECORD));
1386   // Redeclarable
1387   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1388   // Decl
1389   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1390   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1391   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1392   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1393   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1394   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1395   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1396   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1397   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1398   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1399   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1400   // NamedDecl
1401   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1402   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1403   // TypeDecl
1404   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1405   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1406   // TagDecl
1407   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1408   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1409   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1410   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1411   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1412   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1413   Abv->Add(BitCodeAbbrevOp(0));                         // hasExtInfo
1414   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // TypedefNameAnonDecl
1415   // RecordDecl
1416   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // FlexibleArrayMember
1417   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // AnonymousStructUnion
1418   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // hasObjectMember
1419   // DC
1420   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1421   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1422   DeclRecordAbbrev = Stream.EmitAbbrev(Abv);
1423 
1424   // Abbreviation for DECL_PARM_VAR
1425   Abv = new BitCodeAbbrev();
1426   Abv->Add(BitCodeAbbrevOp(serialization::DECL_PARM_VAR));
1427   // Redeclarable
1428   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1429   // Decl
1430   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1431   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1432   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1433   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1434   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1435   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1436   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1437   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1438   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1439   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1440   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1441   // NamedDecl
1442   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1443   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1444   // ValueDecl
1445   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1446   // DeclaratorDecl
1447   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1448   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1449   // VarDecl
1450   Abv->Add(BitCodeAbbrevOp(0));                       // StorageClass
1451   Abv->Add(BitCodeAbbrevOp(0));                       // StorageClassAsWritten
1452   Abv->Add(BitCodeAbbrevOp(0));                       // isThreadSpecified
1453   Abv->Add(BitCodeAbbrevOp(0));                       // hasCXXDirectInitializer
1454   Abv->Add(BitCodeAbbrevOp(0));                       // isExceptionVariable
1455   Abv->Add(BitCodeAbbrevOp(0));                       // isNRVOVariable
1456   Abv->Add(BitCodeAbbrevOp(0));                       // isCXXForRangeDecl
1457   Abv->Add(BitCodeAbbrevOp(0));                       // isARCPseudoStrong
1458   Abv->Add(BitCodeAbbrevOp(0));                       // HasInit
1459   Abv->Add(BitCodeAbbrevOp(0));                   // HasMemberSpecializationInfo
1460   // ParmVarDecl
1461   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsObjCMethodParameter
1462   Abv->Add(BitCodeAbbrevOp(0));                       // ScopeDepth
1463   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ScopeIndex
1464   Abv->Add(BitCodeAbbrevOp(0));                       // ObjCDeclQualifier
1465   Abv->Add(BitCodeAbbrevOp(0));                       // KNRPromoted
1466   Abv->Add(BitCodeAbbrevOp(0));                       // HasInheritedDefaultArg
1467   Abv->Add(BitCodeAbbrevOp(0));                   // HasUninstantiatedDefaultArg
1468   // Type Source Info
1469   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1470   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1471   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1472   DeclParmVarAbbrev = Stream.EmitAbbrev(Abv);
1473 
1474   // Abbreviation for DECL_TYPEDEF
1475   Abv = new BitCodeAbbrev();
1476   Abv->Add(BitCodeAbbrevOp(serialization::DECL_TYPEDEF));
1477   // Redeclarable
1478   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1479   // Decl
1480   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1481   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1482   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1483   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1484   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1485   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1486   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1487   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1488   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1489   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1490   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1491   // NamedDecl
1492   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1493   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1494   // TypeDecl
1495   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1496   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1497   // TypedefDecl
1498   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1499   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1500   DeclTypedefAbbrev = Stream.EmitAbbrev(Abv);
1501 
1502   // Abbreviation for DECL_VAR
1503   Abv = new BitCodeAbbrev();
1504   Abv->Add(BitCodeAbbrevOp(serialization::DECL_VAR));
1505   // Redeclarable
1506   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1507   // Decl
1508   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1509   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1510   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1511   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1512   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1513   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1514   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1515   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1516   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1517   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1518   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1519   // NamedDecl
1520   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1521   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1522   // ValueDecl
1523   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1524   // DeclaratorDecl
1525   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1526   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1527   // VarDecl
1528   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // StorageClass
1529   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // StorageClassAsWritten
1530   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isThreadSpecified
1531   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // CXXDirectInitializer
1532   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isExceptionVariable
1533   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isNRVOVariable
1534   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCXXForRangeDecl
1535   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isARCPseudoStrong
1536   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasInit
1537   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasMemberSpecInfo
1538   // Type Source Info
1539   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1540   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1541   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1542   DeclVarAbbrev = Stream.EmitAbbrev(Abv);
1543 
1544   // Abbreviation for EXPR_DECL_REF
1545   Abv = new BitCodeAbbrev();
1546   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_DECL_REF));
1547   //Stmt
1548   //Expr
1549   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1550   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1551   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1552   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1553   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1554   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1555   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1556   //DeclRefExpr
1557   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HasQualifier
1558   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //GetDeclFound
1559   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ExplicitTemplateArgs
1560   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HadMultipleCandidates
1561   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //RefersToEnclosingLocal
1562   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclRef
1563   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1564   DeclRefExprAbbrev = Stream.EmitAbbrev(Abv);
1565 
1566   // Abbreviation for EXPR_INTEGER_LITERAL
1567   Abv = new BitCodeAbbrev();
1568   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_INTEGER_LITERAL));
1569   //Stmt
1570   //Expr
1571   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1572   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1573   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1574   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1575   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1576   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1577   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1578   //Integer Literal
1579   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1580   Abv->Add(BitCodeAbbrevOp(32));                      // Bit Width
1581   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Value
1582   IntegerLiteralAbbrev = Stream.EmitAbbrev(Abv);
1583 
1584   // Abbreviation for EXPR_CHARACTER_LITERAL
1585   Abv = new BitCodeAbbrev();
1586   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_CHARACTER_LITERAL));
1587   //Stmt
1588   //Expr
1589   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1590   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1591   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1592   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1593   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1594   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1595   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1596   //Character Literal
1597   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getValue
1598   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1599   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //IsWide
1600   CharacterLiteralAbbrev = Stream.EmitAbbrev(Abv);
1601 
1602   Abv = new BitCodeAbbrev();
1603   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_LEXICAL));
1604   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1605   DeclContextLexicalAbbrev = Stream.EmitAbbrev(Abv);
1606 
1607   Abv = new BitCodeAbbrev();
1608   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_VISIBLE));
1609   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1610   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1611   DeclContextVisibleLookupAbbrev = Stream.EmitAbbrev(Abv);
1612 }
1613 
1614 /// isRequiredDecl - Check if this is a "required" Decl, which must be seen by
1615 /// consumers of the AST.
1616 ///
1617 /// Such decls will always be deserialized from the AST file, so we would like
1618 /// this to be as restrictive as possible. Currently the predicate is driven by
1619 /// code generation requirements, if other clients have a different notion of
1620 /// what is "required" then we may have to consider an alternate scheme where
1621 /// clients can iterate over the top-level decls and get information on them,
1622 /// without necessary deserializing them. We could explicitly require such
1623 /// clients to use a separate API call to "realize" the decl. This should be
1624 /// relatively painless since they would presumably only do it for top-level
1625 /// decls.
1626 static bool isRequiredDecl(const Decl *D, ASTContext &Context) {
1627   // An ObjCMethodDecl is never considered as "required" because its
1628   // implementation container always is.
1629 
1630   // File scoped assembly or obj-c implementation must be seen.
1631   if (isa<FileScopeAsmDecl>(D) || isa<ObjCImplDecl>(D))
1632     return true;
1633 
1634   return Context.DeclMustBeEmitted(D);
1635 }
1636 
1637 void ASTWriter::WriteDecl(ASTContext &Context, Decl *D) {
1638   // Switch case IDs are per Decl.
1639   ClearSwitchCaseIDs();
1640 
1641   RecordData Record;
1642   ASTDeclWriter W(*this, Context, Record);
1643 
1644   // Determine the ID for this declaration.
1645   serialization::DeclID ID;
1646   if (D->isFromASTFile())
1647     ID = getDeclID(D);
1648   else {
1649     serialization::DeclID &IDR = DeclIDs[D];
1650     if (IDR == 0)
1651       IDR = NextDeclID++;
1652 
1653     ID= IDR;
1654   }
1655 
1656   bool isReplacingADecl = ID < FirstDeclID;
1657 
1658   // If this declaration is also a DeclContext, write blocks for the
1659   // declarations that lexically stored inside its context and those
1660   // declarations that are visible from its context. These blocks
1661   // are written before the declaration itself so that we can put
1662   // their offsets into the record for the declaration.
1663   uint64_t LexicalOffset = 0;
1664   uint64_t VisibleOffset = 0;
1665   DeclContext *DC = dyn_cast<DeclContext>(D);
1666   if (DC) {
1667     if (isReplacingADecl) {
1668       // It is replacing a decl from a chained PCH; make sure that the
1669       // DeclContext is fully loaded.
1670       if (DC->hasExternalLexicalStorage())
1671         DC->LoadLexicalDeclsFromExternalStorage();
1672       if (DC->hasExternalVisibleStorage())
1673         Chain->completeVisibleDeclsMap(DC);
1674     }
1675     LexicalOffset = WriteDeclContextLexicalBlock(Context, DC);
1676     VisibleOffset = WriteDeclContextVisibleBlock(Context, DC);
1677   }
1678 
1679   if (isReplacingADecl) {
1680     // We're replacing a decl in a previous file.
1681     ReplacedDecls.push_back(ReplacedDeclInfo(ID, Stream.GetCurrentBitNo(),
1682                                              D->getLocation()));
1683   } else {
1684     unsigned Index = ID - FirstDeclID;
1685 
1686     // Record the offset for this declaration
1687     SourceLocation Loc = D->getLocation();
1688     if (DeclOffsets.size() == Index)
1689       DeclOffsets.push_back(DeclOffset(Loc, Stream.GetCurrentBitNo()));
1690     else if (DeclOffsets.size() < Index) {
1691       DeclOffsets.resize(Index+1);
1692       DeclOffsets[Index].setLocation(Loc);
1693       DeclOffsets[Index].BitOffset = Stream.GetCurrentBitNo();
1694     }
1695 
1696     SourceManager &SM = Context.getSourceManager();
1697     if (Loc.isValid() && SM.isLocalSourceLocation(Loc))
1698       associateDeclWithFile(D, ID);
1699   }
1700 
1701   // Build and emit a record for this declaration
1702   Record.clear();
1703   W.Code = (serialization::DeclCode)0;
1704   W.AbbrevToUse = 0;
1705   W.Visit(D);
1706   if (DC) W.VisitDeclContext(DC, LexicalOffset, VisibleOffset);
1707 
1708   if (!W.Code)
1709     llvm::report_fatal_error(StringRef("unexpected declaration kind '") +
1710                             D->getDeclKindName() + "'");
1711   Stream.EmitRecord(W.Code, Record, W.AbbrevToUse);
1712 
1713   // Flush any expressions that were written as part of this declaration.
1714   FlushStmts();
1715 
1716   // Flush C++ base specifiers, if there are any.
1717   FlushCXXBaseSpecifiers();
1718 
1719   // Note "external" declarations so that we can add them to a record in the
1720   // AST file later.
1721   //
1722   // FIXME: This should be renamed, the predicate is much more complicated.
1723   if (isRequiredDecl(D, Context))
1724     ExternalDefinitions.push_back(ID);
1725 }
1726