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 "ASTCommon.h"
16 #include "clang/AST/DeclCXX.h"
17 #include "clang/AST/DeclContextInternals.h"
18 #include "clang/AST/DeclTemplate.h"
19 #include "clang/AST/DeclVisitor.h"
20 #include "clang/AST/Expr.h"
21 #include "clang/Basic/SourceManager.h"
22 #include "clang/Serialization/ASTReader.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(ArrayRef<const Attr*>(D->getAttrs().begin(),
155                                                  D->getAttrs().size()), Record);
156   Record.push_back(D->isImplicit());
157   Record.push_back(D->isUsed(false));
158   Record.push_back(D->isReferenced());
159   Record.push_back(D->isTopLevelDeclInObjCContainer());
160   Record.push_back(D->getAccess());
161   Record.push_back(D->isModulePrivate());
162   Record.push_back(Writer.inferSubmoduleIDFromLocation(D->getLocation()));
163 }
164 
165 void ASTDeclWriter::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
166   llvm_unreachable("Translation units aren't directly serialized");
167 }
168 
169 void ASTDeclWriter::VisitNamedDecl(NamedDecl *D) {
170   VisitDecl(D);
171   Writer.AddDeclarationName(D->getDeclName(), Record);
172 }
173 
174 void ASTDeclWriter::VisitTypeDecl(TypeDecl *D) {
175   VisitNamedDecl(D);
176   Writer.AddSourceLocation(D->getLocStart(), Record);
177   Writer.AddTypeRef(QualType(D->getTypeForDecl(), 0), Record);
178 }
179 
180 void ASTDeclWriter::VisitTypedefNameDecl(TypedefNameDecl *D) {
181   VisitRedeclarable(D);
182   VisitTypeDecl(D);
183   Writer.AddTypeSourceInfo(D->getTypeSourceInfo(), Record);
184 }
185 
186 void ASTDeclWriter::VisitTypedefDecl(TypedefDecl *D) {
187   VisitTypedefNameDecl(D);
188   if (!D->hasAttrs() &&
189       !D->isImplicit() &&
190       !D->isUsed(false) &&
191       D->getFirstDeclaration() == D->getMostRecentDecl() &&
192       !D->isInvalidDecl() &&
193       !D->isReferenced() &&
194       !D->isTopLevelDeclInObjCContainer() &&
195       D->getAccess() == AS_none &&
196       !D->isModulePrivate() &&
197       D->getDeclName().getNameKind() == DeclarationName::Identifier)
198     AbbrevToUse = Writer.getDeclTypedefAbbrev();
199 
200   Code = serialization::DECL_TYPEDEF;
201 }
202 
203 void ASTDeclWriter::VisitTypeAliasDecl(TypeAliasDecl *D) {
204   VisitTypedefNameDecl(D);
205   Code = serialization::DECL_TYPEALIAS;
206 }
207 
208 void ASTDeclWriter::VisitTagDecl(TagDecl *D) {
209   VisitRedeclarable(D);
210   VisitTypeDecl(D);
211   Record.push_back(D->getIdentifierNamespace());
212   Record.push_back((unsigned)D->getTagKind()); // FIXME: stable encoding
213   Record.push_back(D->isCompleteDefinition());
214   Record.push_back(D->isEmbeddedInDeclarator());
215   Record.push_back(D->isFreeStanding());
216   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
217   Record.push_back(D->hasExtInfo());
218   if (D->hasExtInfo())
219     Writer.AddQualifierInfo(*D->getExtInfo(), Record);
220   else
221     Writer.AddDeclRef(D->getTypedefNameForAnonDecl(), Record);
222 }
223 
224 void ASTDeclWriter::VisitEnumDecl(EnumDecl *D) {
225   VisitTagDecl(D);
226   Writer.AddTypeSourceInfo(D->getIntegerTypeSourceInfo(), Record);
227   if (!D->getIntegerTypeSourceInfo())
228     Writer.AddTypeRef(D->getIntegerType(), Record);
229   Writer.AddTypeRef(D->getPromotionType(), Record);
230   Record.push_back(D->getNumPositiveBits());
231   Record.push_back(D->getNumNegativeBits());
232   Record.push_back(D->isScoped());
233   Record.push_back(D->isScopedUsingClassTag());
234   Record.push_back(D->isFixed());
235   if (MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo()) {
236     Writer.AddDeclRef(MemberInfo->getInstantiatedFrom(), Record);
237     Record.push_back(MemberInfo->getTemplateSpecializationKind());
238     Writer.AddSourceLocation(MemberInfo->getPointOfInstantiation(), Record);
239   } else {
240     Writer.AddDeclRef(0, Record);
241   }
242 
243   if (!D->hasAttrs() &&
244       !D->isImplicit() &&
245       !D->isUsed(false) &&
246       !D->hasExtInfo() &&
247       D->getFirstDeclaration() == D->getMostRecentDecl() &&
248       !D->isInvalidDecl() &&
249       !D->isReferenced() &&
250       !D->isTopLevelDeclInObjCContainer() &&
251       D->getAccess() == AS_none &&
252       !D->isModulePrivate() &&
253       !CXXRecordDecl::classofKind(D->getKind()) &&
254       !D->getIntegerTypeSourceInfo() &&
255       D->getDeclName().getNameKind() == DeclarationName::Identifier)
256     AbbrevToUse = Writer.getDeclEnumAbbrev();
257 
258   Code = serialization::DECL_ENUM;
259 }
260 
261 void ASTDeclWriter::VisitRecordDecl(RecordDecl *D) {
262   VisitTagDecl(D);
263   Record.push_back(D->hasFlexibleArrayMember());
264   Record.push_back(D->isAnonymousStructOrUnion());
265   Record.push_back(D->hasObjectMember());
266 
267   if (!D->hasAttrs() &&
268       !D->isImplicit() &&
269       !D->isUsed(false) &&
270       !D->hasExtInfo() &&
271       D->getFirstDeclaration() == D->getMostRecentDecl() &&
272       !D->isInvalidDecl() &&
273       !D->isReferenced() &&
274       !D->isTopLevelDeclInObjCContainer() &&
275       D->getAccess() == AS_none &&
276       !D->isModulePrivate() &&
277       !CXXRecordDecl::classofKind(D->getKind()) &&
278       D->getDeclName().getNameKind() == DeclarationName::Identifier)
279     AbbrevToUse = Writer.getDeclRecordAbbrev();
280 
281   Code = serialization::DECL_RECORD;
282 }
283 
284 void ASTDeclWriter::VisitValueDecl(ValueDecl *D) {
285   VisitNamedDecl(D);
286   Writer.AddTypeRef(D->getType(), Record);
287 }
288 
289 void ASTDeclWriter::VisitEnumConstantDecl(EnumConstantDecl *D) {
290   VisitValueDecl(D);
291   Record.push_back(D->getInitExpr()? 1 : 0);
292   if (D->getInitExpr())
293     Writer.AddStmt(D->getInitExpr());
294   Writer.AddAPSInt(D->getInitVal(), Record);
295 
296   Code = serialization::DECL_ENUM_CONSTANT;
297 }
298 
299 void ASTDeclWriter::VisitDeclaratorDecl(DeclaratorDecl *D) {
300   VisitValueDecl(D);
301   Writer.AddSourceLocation(D->getInnerLocStart(), Record);
302   Record.push_back(D->hasExtInfo());
303   if (D->hasExtInfo())
304     Writer.AddQualifierInfo(*D->getExtInfo(), Record);
305 }
306 
307 void ASTDeclWriter::VisitFunctionDecl(FunctionDecl *D) {
308   VisitRedeclarable(D);
309   VisitDeclaratorDecl(D);
310 
311   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
312   Record.push_back(D->getIdentifierNamespace());
313 
314   // FunctionDecl's body is handled last at ASTWriterDecl::Visit,
315   // after everything else is written.
316 
317   Record.push_back(D->getStorageClass()); // FIXME: stable encoding
318   Record.push_back(D->getStorageClassAsWritten());
319   Record.push_back(D->IsInline);
320   Record.push_back(D->isInlineSpecified());
321   Record.push_back(D->isVirtualAsWritten());
322   Record.push_back(D->isPure());
323   Record.push_back(D->hasInheritedPrototype());
324   Record.push_back(D->hasWrittenPrototype());
325   Record.push_back(D->isDeletedAsWritten());
326   Record.push_back(D->isTrivial());
327   Record.push_back(D->isDefaulted());
328   Record.push_back(D->isExplicitlyDefaulted());
329   Record.push_back(D->hasImplicitReturnZero());
330   Record.push_back(D->isConstexpr());
331   Record.push_back(D->HasSkippedBody);
332   Writer.AddSourceLocation(D->getLocEnd(), Record);
333 
334   Record.push_back(D->getTemplatedKind());
335   switch (D->getTemplatedKind()) {
336   case FunctionDecl::TK_NonTemplate:
337     break;
338   case FunctionDecl::TK_FunctionTemplate:
339     Writer.AddDeclRef(D->getDescribedFunctionTemplate(), Record);
340     break;
341   case FunctionDecl::TK_MemberSpecialization: {
342     MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo();
343     Writer.AddDeclRef(MemberInfo->getInstantiatedFrom(), Record);
344     Record.push_back(MemberInfo->getTemplateSpecializationKind());
345     Writer.AddSourceLocation(MemberInfo->getPointOfInstantiation(), Record);
346     break;
347   }
348   case FunctionDecl::TK_FunctionTemplateSpecialization: {
349     FunctionTemplateSpecializationInfo *
350       FTSInfo = D->getTemplateSpecializationInfo();
351     Writer.AddDeclRef(FTSInfo->getTemplate(), Record);
352     Record.push_back(FTSInfo->getTemplateSpecializationKind());
353 
354     // Template arguments.
355     Writer.AddTemplateArgumentList(FTSInfo->TemplateArguments, Record);
356 
357     // Template args as written.
358     Record.push_back(FTSInfo->TemplateArgumentsAsWritten != 0);
359     if (FTSInfo->TemplateArgumentsAsWritten) {
360       Record.push_back(FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs);
361       for (int i=0, e = FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs;
362              i!=e; ++i)
363         Writer.AddTemplateArgumentLoc((*FTSInfo->TemplateArgumentsAsWritten)[i],
364                                       Record);
365       Writer.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->LAngleLoc,
366                                Record);
367       Writer.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->RAngleLoc,
368                                Record);
369     }
370 
371     Writer.AddSourceLocation(FTSInfo->getPointOfInstantiation(), Record);
372 
373     if (D->isCanonicalDecl()) {
374       // Write the template that contains the specializations set. We will
375       // add a FunctionTemplateSpecializationInfo to it when reading.
376       Writer.AddDeclRef(FTSInfo->getTemplate()->getCanonicalDecl(), Record);
377     }
378     break;
379   }
380   case FunctionDecl::TK_DependentFunctionTemplateSpecialization: {
381     DependentFunctionTemplateSpecializationInfo *
382       DFTSInfo = D->getDependentSpecializationInfo();
383 
384     // Templates.
385     Record.push_back(DFTSInfo->getNumTemplates());
386     for (int i=0, e = DFTSInfo->getNumTemplates(); i != e; ++i)
387       Writer.AddDeclRef(DFTSInfo->getTemplate(i), Record);
388 
389     // Templates args.
390     Record.push_back(DFTSInfo->getNumTemplateArgs());
391     for (int i=0, e = DFTSInfo->getNumTemplateArgs(); i != e; ++i)
392       Writer.AddTemplateArgumentLoc(DFTSInfo->getTemplateArg(i), Record);
393     Writer.AddSourceLocation(DFTSInfo->getLAngleLoc(), Record);
394     Writer.AddSourceLocation(DFTSInfo->getRAngleLoc(), Record);
395     break;
396   }
397   }
398 
399   Record.push_back(D->param_size());
400   for (FunctionDecl::param_iterator P = D->param_begin(), PEnd = D->param_end();
401        P != PEnd; ++P)
402     Writer.AddDeclRef(*P, Record);
403   Code = serialization::DECL_FUNCTION;
404 }
405 
406 void ASTDeclWriter::VisitObjCMethodDecl(ObjCMethodDecl *D) {
407   VisitNamedDecl(D);
408   // FIXME: convert to LazyStmtPtr?
409   // Unlike C/C++, method bodies will never be in header files.
410   bool HasBodyStuff = D->getBody() != 0     ||
411                       D->getSelfDecl() != 0 || D->getCmdDecl() != 0;
412   Record.push_back(HasBodyStuff);
413   if (HasBodyStuff) {
414     Writer.AddStmt(D->getBody());
415     Writer.AddDeclRef(D->getSelfDecl(), Record);
416     Writer.AddDeclRef(D->getCmdDecl(), Record);
417   }
418   Record.push_back(D->isInstanceMethod());
419   Record.push_back(D->isVariadic());
420   Record.push_back(D->isPropertyAccessor());
421   Record.push_back(D->isDefined());
422   Record.push_back(D->IsOverriding);
423   Record.push_back(D->HasSkippedBody);
424 
425   Record.push_back(D->IsRedeclaration);
426   Record.push_back(D->HasRedeclaration);
427   if (D->HasRedeclaration) {
428     assert(Context.getObjCMethodRedeclaration(D));
429     Writer.AddDeclRef(Context.getObjCMethodRedeclaration(D), Record);
430   }
431 
432   // FIXME: stable encoding for @required/@optional
433   Record.push_back(D->getImplementationControl());
434   // FIXME: stable encoding for in/out/inout/bycopy/byref/oneway
435   Record.push_back(D->getObjCDeclQualifier());
436   Record.push_back(D->hasRelatedResultType());
437   Writer.AddTypeRef(D->getResultType(), Record);
438   Writer.AddTypeSourceInfo(D->getResultTypeSourceInfo(), Record);
439   Writer.AddSourceLocation(D->getLocEnd(), Record);
440   Record.push_back(D->param_size());
441   for (ObjCMethodDecl::param_iterator P = D->param_begin(),
442                                    PEnd = D->param_end(); P != PEnd; ++P)
443     Writer.AddDeclRef(*P, Record);
444 
445   Record.push_back(D->SelLocsKind);
446   unsigned NumStoredSelLocs = D->getNumStoredSelLocs();
447   SourceLocation *SelLocs = D->getStoredSelLocs();
448   Record.push_back(NumStoredSelLocs);
449   for (unsigned i = 0; i != NumStoredSelLocs; ++i)
450     Writer.AddSourceLocation(SelLocs[i], Record);
451 
452   Code = serialization::DECL_OBJC_METHOD;
453 }
454 
455 void ASTDeclWriter::VisitObjCContainerDecl(ObjCContainerDecl *D) {
456   VisitNamedDecl(D);
457   Writer.AddSourceLocation(D->getAtStartLoc(), Record);
458   Writer.AddSourceRange(D->getAtEndRange(), Record);
459   // Abstract class (no need to define a stable serialization::DECL code).
460 }
461 
462 void ASTDeclWriter::VisitObjCInterfaceDecl(ObjCInterfaceDecl *D) {
463   VisitRedeclarable(D);
464   VisitObjCContainerDecl(D);
465   Writer.AddTypeRef(QualType(D->getTypeForDecl(), 0), Record);
466 
467   Record.push_back(D->isThisDeclarationADefinition());
468   if (D->isThisDeclarationADefinition()) {
469     // Write the DefinitionData
470     ObjCInterfaceDecl::DefinitionData &Data = D->data();
471 
472     Writer.AddDeclRef(D->getSuperClass(), Record);
473     Writer.AddSourceLocation(D->getSuperClassLoc(), Record);
474     Writer.AddSourceLocation(D->getEndOfDefinitionLoc(), Record);
475 
476     // Write out the protocols that are directly referenced by the @interface.
477     Record.push_back(Data.ReferencedProtocols.size());
478     for (ObjCInterfaceDecl::protocol_iterator P = D->protocol_begin(),
479                                            PEnd = D->protocol_end();
480          P != PEnd; ++P)
481       Writer.AddDeclRef(*P, Record);
482     for (ObjCInterfaceDecl::protocol_loc_iterator PL = D->protocol_loc_begin(),
483          PLEnd = D->protocol_loc_end();
484          PL != PLEnd; ++PL)
485       Writer.AddSourceLocation(*PL, Record);
486 
487     // Write out the protocols that are transitively referenced.
488     Record.push_back(Data.AllReferencedProtocols.size());
489     for (ObjCList<ObjCProtocolDecl>::iterator
490               P = Data.AllReferencedProtocols.begin(),
491            PEnd = Data.AllReferencedProtocols.end();
492          P != PEnd; ++P)
493       Writer.AddDeclRef(*P, Record);
494 
495     if (ObjCCategoryDecl *Cat = D->getCategoryList()) {
496       // Ensure that we write out the set of categories for this class.
497       Writer.ObjCClassesWithCategories.insert(D);
498 
499       // Make sure that the categories get serialized.
500       for (; Cat; Cat = Cat->getNextClassCategory())
501         (void)Writer.GetDeclRef(Cat);
502     }
503   }
504 
505   Code = serialization::DECL_OBJC_INTERFACE;
506 }
507 
508 void ASTDeclWriter::VisitObjCIvarDecl(ObjCIvarDecl *D) {
509   VisitFieldDecl(D);
510   // FIXME: stable encoding for @public/@private/@protected/@package
511   Record.push_back(D->getAccessControl());
512   Record.push_back(D->getSynthesize());
513 
514   if (!D->hasAttrs() &&
515       !D->isImplicit() &&
516       !D->isUsed(false) &&
517       !D->isInvalidDecl() &&
518       !D->isReferenced() &&
519       !D->isModulePrivate() &&
520       !D->getBitWidth() &&
521       !D->hasExtInfo() &&
522       D->getDeclName())
523     AbbrevToUse = Writer.getDeclObjCIvarAbbrev();
524 
525   Code = serialization::DECL_OBJC_IVAR;
526 }
527 
528 void ASTDeclWriter::VisitObjCProtocolDecl(ObjCProtocolDecl *D) {
529   VisitRedeclarable(D);
530   VisitObjCContainerDecl(D);
531 
532   Record.push_back(D->isThisDeclarationADefinition());
533   if (D->isThisDeclarationADefinition()) {
534     Record.push_back(D->protocol_size());
535     for (ObjCProtocolDecl::protocol_iterator
536          I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
537       Writer.AddDeclRef(*I, Record);
538     for (ObjCProtocolDecl::protocol_loc_iterator PL = D->protocol_loc_begin(),
539            PLEnd = D->protocol_loc_end();
540          PL != PLEnd; ++PL)
541       Writer.AddSourceLocation(*PL, Record);
542   }
543 
544   Code = serialization::DECL_OBJC_PROTOCOL;
545 }
546 
547 void ASTDeclWriter::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D) {
548   VisitFieldDecl(D);
549   Code = serialization::DECL_OBJC_AT_DEFS_FIELD;
550 }
551 
552 void ASTDeclWriter::VisitObjCCategoryDecl(ObjCCategoryDecl *D) {
553   VisitObjCContainerDecl(D);
554   Writer.AddSourceLocation(D->getCategoryNameLoc(), Record);
555   Writer.AddSourceLocation(D->getIvarLBraceLoc(), Record);
556   Writer.AddSourceLocation(D->getIvarRBraceLoc(), Record);
557   Writer.AddDeclRef(D->getClassInterface(), Record);
558   Record.push_back(D->protocol_size());
559   for (ObjCCategoryDecl::protocol_iterator
560        I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
561     Writer.AddDeclRef(*I, Record);
562   for (ObjCCategoryDecl::protocol_loc_iterator
563          PL = D->protocol_loc_begin(), PLEnd = D->protocol_loc_end();
564        PL != PLEnd; ++PL)
565     Writer.AddSourceLocation(*PL, Record);
566   Code = serialization::DECL_OBJC_CATEGORY;
567 }
568 
569 void ASTDeclWriter::VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D) {
570   VisitNamedDecl(D);
571   Writer.AddDeclRef(D->getClassInterface(), Record);
572   Code = serialization::DECL_OBJC_COMPATIBLE_ALIAS;
573 }
574 
575 void ASTDeclWriter::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
576   VisitNamedDecl(D);
577   Writer.AddSourceLocation(D->getAtLoc(), Record);
578   Writer.AddSourceLocation(D->getLParenLoc(), Record);
579   Writer.AddTypeSourceInfo(D->getTypeSourceInfo(), Record);
580   // FIXME: stable encoding
581   Record.push_back((unsigned)D->getPropertyAttributes());
582   Record.push_back((unsigned)D->getPropertyAttributesAsWritten());
583   // FIXME: stable encoding
584   Record.push_back((unsigned)D->getPropertyImplementation());
585   Writer.AddDeclarationName(D->getGetterName(), Record);
586   Writer.AddDeclarationName(D->getSetterName(), Record);
587   Writer.AddDeclRef(D->getGetterMethodDecl(), Record);
588   Writer.AddDeclRef(D->getSetterMethodDecl(), Record);
589   Writer.AddDeclRef(D->getPropertyIvarDecl(), Record);
590   Code = serialization::DECL_OBJC_PROPERTY;
591 }
592 
593 void ASTDeclWriter::VisitObjCImplDecl(ObjCImplDecl *D) {
594   VisitObjCContainerDecl(D);
595   Writer.AddDeclRef(D->getClassInterface(), Record);
596   // Abstract class (no need to define a stable serialization::DECL code).
597 }
598 
599 void ASTDeclWriter::VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D) {
600   VisitObjCImplDecl(D);
601   Writer.AddIdentifierRef(D->getIdentifier(), Record);
602   Writer.AddSourceLocation(D->getCategoryNameLoc(), Record);
603   Code = serialization::DECL_OBJC_CATEGORY_IMPL;
604 }
605 
606 void ASTDeclWriter::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
607   VisitObjCImplDecl(D);
608   Writer.AddDeclRef(D->getSuperClass(), Record);
609   Writer.AddSourceLocation(D->getIvarLBraceLoc(), Record);
610   Writer.AddSourceLocation(D->getIvarRBraceLoc(), Record);
611   Record.push_back(D->hasNonZeroConstructors());
612   Record.push_back(D->hasDestructors());
613   Writer.AddCXXCtorInitializers(D->IvarInitializers, D->NumIvarInitializers,
614                                 Record);
615   Code = serialization::DECL_OBJC_IMPLEMENTATION;
616 }
617 
618 void ASTDeclWriter::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
619   VisitDecl(D);
620   Writer.AddSourceLocation(D->getLocStart(), Record);
621   Writer.AddDeclRef(D->getPropertyDecl(), Record);
622   Writer.AddDeclRef(D->getPropertyIvarDecl(), Record);
623   Writer.AddSourceLocation(D->getPropertyIvarDeclLoc(), Record);
624   Writer.AddStmt(D->getGetterCXXConstructor());
625   Writer.AddStmt(D->getSetterCXXAssignment());
626   Code = serialization::DECL_OBJC_PROPERTY_IMPL;
627 }
628 
629 void ASTDeclWriter::VisitFieldDecl(FieldDecl *D) {
630   VisitDeclaratorDecl(D);
631   Record.push_back(D->isMutable());
632   if (D->InitializerOrBitWidth.getInt() != ICIS_NoInit ||
633       D->InitializerOrBitWidth.getPointer()) {
634     Record.push_back(D->InitializerOrBitWidth.getInt() + 1);
635     Writer.AddStmt(D->InitializerOrBitWidth.getPointer());
636   } else {
637     Record.push_back(0);
638   }
639   if (!D->getDeclName())
640     Writer.AddDeclRef(Context.getInstantiatedFromUnnamedFieldDecl(D), Record);
641 
642   if (!D->hasAttrs() &&
643       !D->isImplicit() &&
644       !D->isUsed(false) &&
645       !D->isInvalidDecl() &&
646       !D->isReferenced() &&
647       !D->isTopLevelDeclInObjCContainer() &&
648       !D->isModulePrivate() &&
649       !D->getBitWidth() &&
650       !D->hasInClassInitializer() &&
651       !D->hasExtInfo() &&
652       !ObjCIvarDecl::classofKind(D->getKind()) &&
653       !ObjCAtDefsFieldDecl::classofKind(D->getKind()) &&
654       D->getDeclName())
655     AbbrevToUse = Writer.getDeclFieldAbbrev();
656 
657   Code = serialization::DECL_FIELD;
658 }
659 
660 void ASTDeclWriter::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
661   VisitValueDecl(D);
662   Record.push_back(D->getChainingSize());
663 
664   for (IndirectFieldDecl::chain_iterator
665        P = D->chain_begin(),
666        PEnd = D->chain_end(); P != PEnd; ++P)
667     Writer.AddDeclRef(*P, Record);
668   Code = serialization::DECL_INDIRECTFIELD;
669 }
670 
671 void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
672   VisitRedeclarable(D);
673   VisitDeclaratorDecl(D);
674   Record.push_back(D->getStorageClass()); // FIXME: stable encoding
675   Record.push_back(D->getStorageClassAsWritten());
676   Record.push_back(D->isThreadSpecified());
677   Record.push_back(D->getInitStyle());
678   Record.push_back(D->isExceptionVariable());
679   Record.push_back(D->isNRVOVariable());
680   Record.push_back(D->isCXXForRangeDecl());
681   Record.push_back(D->isARCPseudoStrong());
682   Record.push_back(D->isConstexpr());
683 
684   if (D->getInit()) {
685     Record.push_back(!D->isInitKnownICE() ? 1 : (D->isInitICE() ? 3 : 2));
686     Writer.AddStmt(D->getInit());
687   } else {
688     Record.push_back(0);
689   }
690 
691   MemberSpecializationInfo *SpecInfo
692     = D->isStaticDataMember() ? D->getMemberSpecializationInfo() : 0;
693   Record.push_back(SpecInfo != 0);
694   if (SpecInfo) {
695     Writer.AddDeclRef(SpecInfo->getInstantiatedFrom(), Record);
696     Record.push_back(SpecInfo->getTemplateSpecializationKind());
697     Writer.AddSourceLocation(SpecInfo->getPointOfInstantiation(), Record);
698   }
699 
700   if (!D->hasAttrs() &&
701       !D->isImplicit() &&
702       !D->isUsed(false) &&
703       !D->isInvalidDecl() &&
704       !D->isReferenced() &&
705       !D->isTopLevelDeclInObjCContainer() &&
706       D->getAccess() == AS_none &&
707       !D->isModulePrivate() &&
708       D->getDeclName().getNameKind() == DeclarationName::Identifier &&
709       !D->hasExtInfo() &&
710       D->getFirstDeclaration() == D->getMostRecentDecl() &&
711       D->getInitStyle() == VarDecl::CInit &&
712       D->getInit() == 0 &&
713       !isa<ParmVarDecl>(D) &&
714       !D->isConstexpr() &&
715       !SpecInfo)
716     AbbrevToUse = Writer.getDeclVarAbbrev();
717 
718   Code = serialization::DECL_VAR;
719 }
720 
721 void ASTDeclWriter::VisitImplicitParamDecl(ImplicitParamDecl *D) {
722   VisitVarDecl(D);
723   Code = serialization::DECL_IMPLICIT_PARAM;
724 }
725 
726 void ASTDeclWriter::VisitParmVarDecl(ParmVarDecl *D) {
727   VisitVarDecl(D);
728   Record.push_back(D->isObjCMethodParameter());
729   Record.push_back(D->getFunctionScopeDepth());
730   Record.push_back(D->getFunctionScopeIndex());
731   Record.push_back(D->getObjCDeclQualifier()); // FIXME: stable encoding
732   Record.push_back(D->isKNRPromoted());
733   Record.push_back(D->hasInheritedDefaultArg());
734   Record.push_back(D->hasUninstantiatedDefaultArg());
735   if (D->hasUninstantiatedDefaultArg())
736     Writer.AddStmt(D->getUninstantiatedDefaultArg());
737   Code = serialization::DECL_PARM_VAR;
738 
739   assert(!D->isARCPseudoStrong()); // can be true of ImplicitParamDecl
740 
741   // If the assumptions about the DECL_PARM_VAR abbrev are true, use it.  Here
742   // we dynamically check for the properties that we optimize for, but don't
743   // know are true of all PARM_VAR_DECLs.
744   if (!D->hasAttrs() &&
745       !D->hasExtInfo() &&
746       !D->isImplicit() &&
747       !D->isUsed(false) &&
748       !D->isInvalidDecl() &&
749       !D->isReferenced() &&
750       D->getAccess() == AS_none &&
751       !D->isModulePrivate() &&
752       D->getStorageClass() == 0 &&
753       D->getInitStyle() == VarDecl::CInit && // Can params have anything else?
754       D->getFunctionScopeDepth() == 0 &&
755       D->getObjCDeclQualifier() == 0 &&
756       !D->isKNRPromoted() &&
757       !D->hasInheritedDefaultArg() &&
758       D->getInit() == 0 &&
759       !D->hasUninstantiatedDefaultArg())  // No default expr.
760     AbbrevToUse = Writer.getDeclParmVarAbbrev();
761 
762   // Check things we know are true of *every* PARM_VAR_DECL, which is more than
763   // just us assuming it.
764   assert(!D->isThreadSpecified() && "PARM_VAR_DECL can't be __thread");
765   assert(D->getAccess() == AS_none && "PARM_VAR_DECL can't be public/private");
766   assert(!D->isExceptionVariable() && "PARM_VAR_DECL can't be exception var");
767   assert(D->getPreviousDecl() == 0 && "PARM_VAR_DECL can't be redecl");
768   assert(!D->isStaticDataMember() &&
769          "PARM_VAR_DECL can't be static data member");
770 }
771 
772 void ASTDeclWriter::VisitFileScopeAsmDecl(FileScopeAsmDecl *D) {
773   VisitDecl(D);
774   Writer.AddStmt(D->getAsmString());
775   Writer.AddSourceLocation(D->getRParenLoc(), Record);
776   Code = serialization::DECL_FILE_SCOPE_ASM;
777 }
778 
779 void ASTDeclWriter::VisitBlockDecl(BlockDecl *D) {
780   VisitDecl(D);
781   Writer.AddStmt(D->getBody());
782   Writer.AddTypeSourceInfo(D->getSignatureAsWritten(), Record);
783   Record.push_back(D->param_size());
784   for (FunctionDecl::param_iterator P = D->param_begin(), PEnd = D->param_end();
785        P != PEnd; ++P)
786     Writer.AddDeclRef(*P, Record);
787   Record.push_back(D->isVariadic());
788   Record.push_back(D->blockMissingReturnType());
789   Record.push_back(D->isConversionFromLambda());
790   Record.push_back(D->capturesCXXThis());
791   Record.push_back(D->getNumCaptures());
792   for (BlockDecl::capture_iterator
793          i = D->capture_begin(), e = D->capture_end(); i != e; ++i) {
794     const BlockDecl::Capture &capture = *i;
795     Writer.AddDeclRef(capture.getVariable(), Record);
796 
797     unsigned flags = 0;
798     if (capture.isByRef()) flags |= 1;
799     if (capture.isNested()) flags |= 2;
800     if (capture.hasCopyExpr()) flags |= 4;
801     Record.push_back(flags);
802 
803     if (capture.hasCopyExpr()) Writer.AddStmt(capture.getCopyExpr());
804   }
805 
806   Code = serialization::DECL_BLOCK;
807 }
808 
809 void ASTDeclWriter::VisitLinkageSpecDecl(LinkageSpecDecl *D) {
810   VisitDecl(D);
811   Record.push_back(D->getLanguage());
812   Writer.AddSourceLocation(D->getExternLoc(), Record);
813   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
814   Code = serialization::DECL_LINKAGE_SPEC;
815 }
816 
817 void ASTDeclWriter::VisitLabelDecl(LabelDecl *D) {
818   VisitNamedDecl(D);
819   Writer.AddSourceLocation(D->getLocStart(), Record);
820   Code = serialization::DECL_LABEL;
821 }
822 
823 
824 void ASTDeclWriter::VisitNamespaceDecl(NamespaceDecl *D) {
825   VisitRedeclarable(D);
826   VisitNamedDecl(D);
827   Record.push_back(D->isInline());
828   Writer.AddSourceLocation(D->getLocStart(), Record);
829   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
830 
831   if (D->isOriginalNamespace())
832     Writer.AddDeclRef(D->getAnonymousNamespace(), Record);
833   Code = serialization::DECL_NAMESPACE;
834 
835   if (Writer.hasChain() && !D->isOriginalNamespace() &&
836       D->getOriginalNamespace()->isFromASTFile()) {
837     NamespaceDecl *NS = D->getOriginalNamespace();
838     Writer.AddUpdatedDeclContext(NS);
839 
840     // Make sure all visible decls are written. They will be recorded later.
841     if (StoredDeclsMap *Map = NS->buildLookup()) {
842       for (StoredDeclsMap::iterator D = Map->begin(), DEnd = Map->end();
843            D != DEnd; ++D) {
844         DeclContext::lookup_result R = D->second.getLookupResult();
845         for (DeclContext::lookup_iterator I = R.begin(), E = R.end(); I != E;
846              ++I)
847           Writer.GetDeclRef(*I);
848       }
849     }
850   }
851 
852   if (Writer.hasChain() && D->isAnonymousNamespace() &&
853       D == D->getMostRecentDecl()) {
854     // This is a most recent reopening of the anonymous namespace. If its parent
855     // is in a previous PCH (or is the TU), mark that parent for update, because
856     // the original namespace always points to the latest re-opening of its
857     // anonymous namespace.
858     Decl *Parent = cast<Decl>(
859         D->getParent()->getRedeclContext()->getPrimaryContext());
860     if (Parent->isFromASTFile() || isa<TranslationUnitDecl>(Parent)) {
861       ASTWriter::UpdateRecord &Record = Writer.DeclUpdates[Parent];
862       Record.push_back(UPD_CXX_ADDED_ANONYMOUS_NAMESPACE);
863       Writer.AddDeclRef(D, Record);
864     }
865   }
866 }
867 
868 void ASTDeclWriter::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
869   VisitNamedDecl(D);
870   Writer.AddSourceLocation(D->getNamespaceLoc(), Record);
871   Writer.AddSourceLocation(D->getTargetNameLoc(), Record);
872   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
873   Writer.AddDeclRef(D->getNamespace(), Record);
874   Code = serialization::DECL_NAMESPACE_ALIAS;
875 }
876 
877 void ASTDeclWriter::VisitUsingDecl(UsingDecl *D) {
878   VisitNamedDecl(D);
879   Writer.AddSourceLocation(D->getUsingLocation(), Record);
880   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
881   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
882   Writer.AddDeclRef(D->FirstUsingShadow.getPointer(), Record);
883   Record.push_back(D->isTypeName());
884   Writer.AddDeclRef(Context.getInstantiatedFromUsingDecl(D), Record);
885   Code = serialization::DECL_USING;
886 }
887 
888 void ASTDeclWriter::VisitUsingShadowDecl(UsingShadowDecl *D) {
889   VisitNamedDecl(D);
890   Writer.AddDeclRef(D->getTargetDecl(), Record);
891   Writer.AddDeclRef(D->UsingOrNextShadow, Record);
892   Writer.AddDeclRef(Context.getInstantiatedFromUsingShadowDecl(D), Record);
893   Code = serialization::DECL_USING_SHADOW;
894 }
895 
896 void ASTDeclWriter::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
897   VisitNamedDecl(D);
898   Writer.AddSourceLocation(D->getUsingLoc(), Record);
899   Writer.AddSourceLocation(D->getNamespaceKeyLocation(), Record);
900   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
901   Writer.AddDeclRef(D->getNominatedNamespace(), Record);
902   Writer.AddDeclRef(dyn_cast<Decl>(D->getCommonAncestor()), Record);
903   Code = serialization::DECL_USING_DIRECTIVE;
904 }
905 
906 void ASTDeclWriter::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
907   VisitValueDecl(D);
908   Writer.AddSourceLocation(D->getUsingLoc(), Record);
909   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
910   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
911   Code = serialization::DECL_UNRESOLVED_USING_VALUE;
912 }
913 
914 void ASTDeclWriter::VisitUnresolvedUsingTypenameDecl(
915                                                UnresolvedUsingTypenameDecl *D) {
916   VisitTypeDecl(D);
917   Writer.AddSourceLocation(D->getTypenameLoc(), Record);
918   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
919   Code = serialization::DECL_UNRESOLVED_USING_TYPENAME;
920 }
921 
922 void ASTDeclWriter::VisitCXXRecordDecl(CXXRecordDecl *D) {
923   VisitRecordDecl(D);
924   Record.push_back(D->isThisDeclarationADefinition());
925   if (D->isThisDeclarationADefinition())
926     Writer.AddCXXDefinitionData(D, Record);
927 
928   enum {
929     CXXRecNotTemplate = 0, CXXRecTemplate, CXXRecMemberSpecialization
930   };
931   if (ClassTemplateDecl *TemplD = D->getDescribedClassTemplate()) {
932     Record.push_back(CXXRecTemplate);
933     Writer.AddDeclRef(TemplD, Record);
934   } else if (MemberSpecializationInfo *MSInfo
935                = D->getMemberSpecializationInfo()) {
936     Record.push_back(CXXRecMemberSpecialization);
937     Writer.AddDeclRef(MSInfo->getInstantiatedFrom(), Record);
938     Record.push_back(MSInfo->getTemplateSpecializationKind());
939     Writer.AddSourceLocation(MSInfo->getPointOfInstantiation(), Record);
940   } else {
941     Record.push_back(CXXRecNotTemplate);
942   }
943 
944   // Store the key function to avoid deserializing every method so we can
945   // compute it.
946   if (D->IsCompleteDefinition)
947     Writer.AddDeclRef(Context.getKeyFunction(D), Record);
948 
949   Code = serialization::DECL_CXX_RECORD;
950 }
951 
952 void ASTDeclWriter::VisitCXXMethodDecl(CXXMethodDecl *D) {
953   VisitFunctionDecl(D);
954   if (D->isCanonicalDecl()) {
955     Record.push_back(D->size_overridden_methods());
956     for (CXXMethodDecl::method_iterator
957            I = D->begin_overridden_methods(), E = D->end_overridden_methods();
958            I != E; ++I)
959       Writer.AddDeclRef(*I, Record);
960   } else {
961     // We only need to record overridden methods once for the canonical decl.
962     Record.push_back(0);
963   }
964   Code = serialization::DECL_CXX_METHOD;
965 }
966 
967 void ASTDeclWriter::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
968   VisitCXXMethodDecl(D);
969 
970   Record.push_back(D->IsExplicitSpecified);
971   Record.push_back(D->ImplicitlyDefined);
972   Writer.AddCXXCtorInitializers(D->CtorInitializers, D->NumCtorInitializers,
973                                 Record);
974 
975   Code = serialization::DECL_CXX_CONSTRUCTOR;
976 }
977 
978 void ASTDeclWriter::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
979   VisitCXXMethodDecl(D);
980 
981   Record.push_back(D->ImplicitlyDefined);
982   Writer.AddDeclRef(D->OperatorDelete, Record);
983 
984   Code = serialization::DECL_CXX_DESTRUCTOR;
985 }
986 
987 void ASTDeclWriter::VisitCXXConversionDecl(CXXConversionDecl *D) {
988   VisitCXXMethodDecl(D);
989   Record.push_back(D->IsExplicitSpecified);
990   Code = serialization::DECL_CXX_CONVERSION;
991 }
992 
993 void ASTDeclWriter::VisitImportDecl(ImportDecl *D) {
994   VisitDecl(D);
995   Record.push_back(Writer.getSubmoduleID(D->getImportedModule()));
996   ArrayRef<SourceLocation> IdentifierLocs = D->getIdentifierLocs();
997   Record.push_back(!IdentifierLocs.empty());
998   if (IdentifierLocs.empty()) {
999     Writer.AddSourceLocation(D->getLocEnd(), Record);
1000     Record.push_back(1);
1001   } else {
1002     for (unsigned I = 0, N = IdentifierLocs.size(); I != N; ++I)
1003       Writer.AddSourceLocation(IdentifierLocs[I], Record);
1004     Record.push_back(IdentifierLocs.size());
1005   }
1006   // Note: the number of source locations must always be the last element in
1007   // the record.
1008   Code = serialization::DECL_IMPORT;
1009 }
1010 
1011 void ASTDeclWriter::VisitAccessSpecDecl(AccessSpecDecl *D) {
1012   VisitDecl(D);
1013   Writer.AddSourceLocation(D->getColonLoc(), Record);
1014   Code = serialization::DECL_ACCESS_SPEC;
1015 }
1016 
1017 void ASTDeclWriter::VisitFriendDecl(FriendDecl *D) {
1018   VisitDecl(D);
1019   Record.push_back(D->Friend.is<TypeSourceInfo*>());
1020   if (D->Friend.is<TypeSourceInfo*>())
1021     Writer.AddTypeSourceInfo(D->Friend.get<TypeSourceInfo*>(), Record);
1022   else
1023     Writer.AddDeclRef(D->Friend.get<NamedDecl*>(), Record);
1024   Writer.AddDeclRef(D->getNextFriend(), Record);
1025   Record.push_back(D->UnsupportedFriend);
1026   Writer.AddSourceLocation(D->FriendLoc, Record);
1027   Code = serialization::DECL_FRIEND;
1028 }
1029 
1030 void ASTDeclWriter::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
1031   VisitDecl(D);
1032   Record.push_back(D->getNumTemplateParameters());
1033   for (unsigned i = 0, e = D->getNumTemplateParameters(); i != e; ++i)
1034     Writer.AddTemplateParameterList(D->getTemplateParameterList(i), Record);
1035   Record.push_back(D->getFriendDecl() != 0);
1036   if (D->getFriendDecl())
1037     Writer.AddDeclRef(D->getFriendDecl(), Record);
1038   else
1039     Writer.AddTypeSourceInfo(D->getFriendType(), Record);
1040   Writer.AddSourceLocation(D->getFriendLoc(), Record);
1041   Code = serialization::DECL_FRIEND_TEMPLATE;
1042 }
1043 
1044 void ASTDeclWriter::VisitTemplateDecl(TemplateDecl *D) {
1045   VisitNamedDecl(D);
1046 
1047   Writer.AddDeclRef(D->getTemplatedDecl(), Record);
1048   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
1049 }
1050 
1051 void ASTDeclWriter::VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D) {
1052   VisitRedeclarable(D);
1053 
1054   // Emit data to initialize CommonOrPrev before VisitTemplateDecl so that
1055   // getCommonPtr() can be used while this is still initializing.
1056   if (D->isFirstDeclaration()) {
1057     // This declaration owns the 'common' pointer, so serialize that data now.
1058     Writer.AddDeclRef(D->getInstantiatedFromMemberTemplate(), Record);
1059     if (D->getInstantiatedFromMemberTemplate())
1060       Record.push_back(D->isMemberSpecialization());
1061   }
1062 
1063   VisitTemplateDecl(D);
1064   Record.push_back(D->getIdentifierNamespace());
1065 }
1066 
1067 void ASTDeclWriter::VisitClassTemplateDecl(ClassTemplateDecl *D) {
1068   VisitRedeclarableTemplateDecl(D);
1069 
1070   if (D->isFirstDeclaration()) {
1071     typedef llvm::FoldingSetVector<ClassTemplateSpecializationDecl> CTSDSetTy;
1072     CTSDSetTy &CTSDSet = D->getSpecializations();
1073     Record.push_back(CTSDSet.size());
1074     for (CTSDSetTy::iterator I=CTSDSet.begin(), E = CTSDSet.end(); I!=E; ++I) {
1075       assert(I->isCanonicalDecl() && "Expected only canonical decls in set");
1076       Writer.AddDeclRef(&*I, Record);
1077     }
1078 
1079     typedef llvm::FoldingSetVector<ClassTemplatePartialSpecializationDecl>
1080       CTPSDSetTy;
1081     CTPSDSetTy &CTPSDSet = D->getPartialSpecializations();
1082     Record.push_back(CTPSDSet.size());
1083     for (CTPSDSetTy::iterator I=CTPSDSet.begin(), E=CTPSDSet.end(); I!=E; ++I) {
1084       assert(I->isCanonicalDecl() && "Expected only canonical decls in set");
1085       Writer.AddDeclRef(&*I, Record);
1086     }
1087 
1088     Writer.AddTypeRef(D->getCommonPtr()->InjectedClassNameType, Record);
1089   }
1090   Code = serialization::DECL_CLASS_TEMPLATE;
1091 }
1092 
1093 void ASTDeclWriter::VisitClassTemplateSpecializationDecl(
1094                                            ClassTemplateSpecializationDecl *D) {
1095   VisitCXXRecordDecl(D);
1096 
1097   llvm::PointerUnion<ClassTemplateDecl *,
1098                      ClassTemplatePartialSpecializationDecl *> InstFrom
1099     = D->getSpecializedTemplateOrPartial();
1100   if (Decl *InstFromD = InstFrom.dyn_cast<ClassTemplateDecl *>()) {
1101     Writer.AddDeclRef(InstFromD, Record);
1102   } else {
1103     Writer.AddDeclRef(InstFrom.get<ClassTemplatePartialSpecializationDecl *>(),
1104                       Record);
1105     Writer.AddTemplateArgumentList(&D->getTemplateInstantiationArgs(), Record);
1106   }
1107 
1108   // Explicit info.
1109   Writer.AddTypeSourceInfo(D->getTypeAsWritten(), Record);
1110   if (D->getTypeAsWritten()) {
1111     Writer.AddSourceLocation(D->getExternLoc(), Record);
1112     Writer.AddSourceLocation(D->getTemplateKeywordLoc(), Record);
1113   }
1114 
1115   Writer.AddTemplateArgumentList(&D->getTemplateArgs(), Record);
1116   Writer.AddSourceLocation(D->getPointOfInstantiation(), Record);
1117   Record.push_back(D->getSpecializationKind());
1118   Record.push_back(D->isCanonicalDecl());
1119 
1120   if (D->isCanonicalDecl()) {
1121     // When reading, we'll add it to the folding set of the following template.
1122     Writer.AddDeclRef(D->getSpecializedTemplate()->getCanonicalDecl(), Record);
1123   }
1124 
1125   Code = serialization::DECL_CLASS_TEMPLATE_SPECIALIZATION;
1126 }
1127 
1128 void ASTDeclWriter::VisitClassTemplatePartialSpecializationDecl(
1129                                     ClassTemplatePartialSpecializationDecl *D) {
1130   VisitClassTemplateSpecializationDecl(D);
1131 
1132   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
1133 
1134   Record.push_back(D->getNumTemplateArgsAsWritten());
1135   for (int i = 0, e = D->getNumTemplateArgsAsWritten(); i != e; ++i)
1136     Writer.AddTemplateArgumentLoc(D->getTemplateArgsAsWritten()[i], Record);
1137 
1138   Record.push_back(D->getSequenceNumber());
1139 
1140   // These are read/set from/to the first declaration.
1141   if (D->getPreviousDecl() == 0) {
1142     Writer.AddDeclRef(D->getInstantiatedFromMember(), Record);
1143     Record.push_back(D->isMemberSpecialization());
1144   }
1145 
1146   Code = serialization::DECL_CLASS_TEMPLATE_PARTIAL_SPECIALIZATION;
1147 }
1148 
1149 void ASTDeclWriter::VisitClassScopeFunctionSpecializationDecl(
1150                                     ClassScopeFunctionSpecializationDecl *D) {
1151   VisitDecl(D);
1152   Writer.AddDeclRef(D->getSpecialization(), Record);
1153   Code = serialization::DECL_CLASS_SCOPE_FUNCTION_SPECIALIZATION;
1154 }
1155 
1156 
1157 void ASTDeclWriter::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
1158   VisitRedeclarableTemplateDecl(D);
1159 
1160   if (D->isFirstDeclaration()) {
1161     // This FunctionTemplateDecl owns the CommonPtr; write it.
1162 
1163     // Write the function specialization declarations.
1164     Record.push_back(D->getSpecializations().size());
1165     for (llvm::FoldingSetVector<FunctionTemplateSpecializationInfo>::iterator
1166            I = D->getSpecializations().begin(),
1167            E = D->getSpecializations().end()   ; I != E; ++I) {
1168       assert(I->Function->isCanonicalDecl() &&
1169              "Expected only canonical decls in set");
1170       Writer.AddDeclRef(I->Function, Record);
1171     }
1172   }
1173   Code = serialization::DECL_FUNCTION_TEMPLATE;
1174 }
1175 
1176 void ASTDeclWriter::VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D) {
1177   VisitTypeDecl(D);
1178 
1179   Record.push_back(D->wasDeclaredWithTypename());
1180   Record.push_back(D->defaultArgumentWasInherited());
1181   Writer.AddTypeSourceInfo(D->getDefaultArgumentInfo(), Record);
1182 
1183   Code = serialization::DECL_TEMPLATE_TYPE_PARM;
1184 }
1185 
1186 void ASTDeclWriter::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
1187   // For an expanded parameter pack, record the number of expansion types here
1188   // so that it's easier for deserialization to allocate the right amount of
1189   // memory.
1190   if (D->isExpandedParameterPack())
1191     Record.push_back(D->getNumExpansionTypes());
1192 
1193   VisitDeclaratorDecl(D);
1194   // TemplateParmPosition.
1195   Record.push_back(D->getDepth());
1196   Record.push_back(D->getPosition());
1197 
1198   if (D->isExpandedParameterPack()) {
1199     for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
1200       Writer.AddTypeRef(D->getExpansionType(I), Record);
1201       Writer.AddTypeSourceInfo(D->getExpansionTypeSourceInfo(I), Record);
1202     }
1203 
1204     Code = serialization::DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK;
1205   } else {
1206     // Rest of NonTypeTemplateParmDecl.
1207     Record.push_back(D->isParameterPack());
1208     Record.push_back(D->getDefaultArgument() != 0);
1209     if (D->getDefaultArgument()) {
1210       Writer.AddStmt(D->getDefaultArgument());
1211       Record.push_back(D->defaultArgumentWasInherited());
1212     }
1213     Code = serialization::DECL_NON_TYPE_TEMPLATE_PARM;
1214   }
1215 }
1216 
1217 void ASTDeclWriter::VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D) {
1218   // For an expanded parameter pack, record the number of expansion types here
1219   // so that it's easier for deserialization to allocate the right amount of
1220   // memory.
1221   if (D->isExpandedParameterPack())
1222     Record.push_back(D->getNumExpansionTemplateParameters());
1223 
1224   VisitTemplateDecl(D);
1225   // TemplateParmPosition.
1226   Record.push_back(D->getDepth());
1227   Record.push_back(D->getPosition());
1228 
1229   if (D->isExpandedParameterPack()) {
1230     for (unsigned I = 0, N = D->getNumExpansionTemplateParameters();
1231          I != N; ++I)
1232       Writer.AddTemplateParameterList(D->getExpansionTemplateParameters(I),
1233                                       Record);
1234     Code = serialization::DECL_EXPANDED_TEMPLATE_TEMPLATE_PARM_PACK;
1235   } else {
1236     // Rest of TemplateTemplateParmDecl.
1237     Writer.AddTemplateArgumentLoc(D->getDefaultArgument(), Record);
1238     Record.push_back(D->defaultArgumentWasInherited());
1239     Record.push_back(D->isParameterPack());
1240     Code = serialization::DECL_TEMPLATE_TEMPLATE_PARM;
1241   }
1242 }
1243 
1244 void ASTDeclWriter::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
1245   VisitRedeclarableTemplateDecl(D);
1246   Code = serialization::DECL_TYPE_ALIAS_TEMPLATE;
1247 }
1248 
1249 void ASTDeclWriter::VisitStaticAssertDecl(StaticAssertDecl *D) {
1250   VisitDecl(D);
1251   Writer.AddStmt(D->getAssertExpr());
1252   Record.push_back(D->isFailed());
1253   Writer.AddStmt(D->getMessage());
1254   Writer.AddSourceLocation(D->getRParenLoc(), Record);
1255   Code = serialization::DECL_STATIC_ASSERT;
1256 }
1257 
1258 /// \brief Emit the DeclContext part of a declaration context decl.
1259 ///
1260 /// \param LexicalOffset the offset at which the DECL_CONTEXT_LEXICAL
1261 /// block for this declaration context is stored. May be 0 to indicate
1262 /// that there are no declarations stored within this context.
1263 ///
1264 /// \param VisibleOffset the offset at which the DECL_CONTEXT_VISIBLE
1265 /// block for this declaration context is stored. May be 0 to indicate
1266 /// that there are no declarations visible from this context. Note
1267 /// that this value will not be emitted for non-primary declaration
1268 /// contexts.
1269 void ASTDeclWriter::VisitDeclContext(DeclContext *DC, uint64_t LexicalOffset,
1270                                      uint64_t VisibleOffset) {
1271   Record.push_back(LexicalOffset);
1272   Record.push_back(VisibleOffset);
1273 }
1274 
1275 template <typename T>
1276 void ASTDeclWriter::VisitRedeclarable(Redeclarable<T> *D) {
1277   T *First = D->getFirstDeclaration();
1278   if (First->getMostRecentDecl() != First) {
1279     // There is more than one declaration of this entity, so we will need to
1280     // write a redeclaration chain.
1281     Writer.AddDeclRef(First, Record);
1282     Writer.Redeclarations.insert(First);
1283 
1284     // Make sure that we serialize both the previous and the most-recent
1285     // declarations, which (transitively) ensures that all declarations in the
1286     // chain get serialized.
1287     (void)Writer.GetDeclRef(D->getPreviousDecl());
1288     (void)Writer.GetDeclRef(First->getMostRecentDecl());
1289   } else {
1290     // We use the sentinel value 0 to indicate an only declaration.
1291     Record.push_back(0);
1292   }
1293 
1294 }
1295 
1296 //===----------------------------------------------------------------------===//
1297 // ASTWriter Implementation
1298 //===----------------------------------------------------------------------===//
1299 
1300 void ASTWriter::WriteDeclsBlockAbbrevs() {
1301   using namespace llvm;
1302 
1303   BitCodeAbbrev *Abv;
1304 
1305   // Abbreviation for DECL_FIELD
1306   Abv = new BitCodeAbbrev();
1307   Abv->Add(BitCodeAbbrevOp(serialization::DECL_FIELD));
1308   // Decl
1309   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1310   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1311   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1312   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1313   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1314   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1315   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1316   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1317   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1318   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1319   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1320   // NamedDecl
1321   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1322   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1323   // ValueDecl
1324   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1325   // DeclaratorDecl
1326   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1327   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1328   // FieldDecl
1329   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1330   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1331   // Type Source Info
1332   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1333   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1334   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1335   DeclFieldAbbrev = Stream.EmitAbbrev(Abv);
1336 
1337   // Abbreviation for DECL_OBJC_IVAR
1338   Abv = new BitCodeAbbrev();
1339   Abv->Add(BitCodeAbbrevOp(serialization::DECL_OBJC_IVAR));
1340   // Decl
1341   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1342   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1343   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1344   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1345   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1346   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1347   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1348   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1349   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1350   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1351   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1352   // NamedDecl
1353   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1354   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1355   // ValueDecl
1356   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1357   // DeclaratorDecl
1358   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1359   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1360   // FieldDecl
1361   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1362   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1363   // ObjC Ivar
1364   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getAccessControl
1365   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getSynthesize
1366   // Type Source Info
1367   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1368   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1369   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1370   DeclObjCIvarAbbrev = Stream.EmitAbbrev(Abv);
1371 
1372   // Abbreviation for DECL_ENUM
1373   Abv = new BitCodeAbbrev();
1374   Abv->Add(BitCodeAbbrevOp(serialization::DECL_ENUM));
1375   // Redeclarable
1376   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1377   // Decl
1378   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1379   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1380   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1381   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1382   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1383   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1384   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1385   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1386   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1387   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1388   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1389   // NamedDecl
1390   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1391   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1392   // TypeDecl
1393   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1394   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1395   // TagDecl
1396   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1397   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1398   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1399   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1400   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1401   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1402   Abv->Add(BitCodeAbbrevOp(0));                         // hasExtInfo
1403   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // TypedefNameAnonDecl
1404   // EnumDecl
1405   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // AddTypeRef
1406   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IntegerType
1407   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getPromotionType
1408   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumPositiveBits
1409   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumNegativeBits
1410   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScoped
1411   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScopedUsingClassTag
1412   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isFixed
1413   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // InstantiatedMembEnum
1414   // DC
1415   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1416   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1417   DeclEnumAbbrev = Stream.EmitAbbrev(Abv);
1418 
1419   // Abbreviation for DECL_RECORD
1420   Abv = new BitCodeAbbrev();
1421   Abv->Add(BitCodeAbbrevOp(serialization::DECL_RECORD));
1422   // Redeclarable
1423   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1424   // Decl
1425   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1426   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1427   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1428   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1429   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1430   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1431   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1432   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1433   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1434   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1435   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1436   // NamedDecl
1437   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1438   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1439   // TypeDecl
1440   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1441   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1442   // TagDecl
1443   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1444   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1445   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1446   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1447   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1448   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1449   Abv->Add(BitCodeAbbrevOp(0));                         // hasExtInfo
1450   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // TypedefNameAnonDecl
1451   // RecordDecl
1452   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // FlexibleArrayMember
1453   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // AnonymousStructUnion
1454   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // hasObjectMember
1455   // DC
1456   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1457   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1458   DeclRecordAbbrev = Stream.EmitAbbrev(Abv);
1459 
1460   // Abbreviation for DECL_PARM_VAR
1461   Abv = new BitCodeAbbrev();
1462   Abv->Add(BitCodeAbbrevOp(serialization::DECL_PARM_VAR));
1463   // Redeclarable
1464   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1465   // Decl
1466   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1467   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1468   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1469   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1470   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1471   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1472   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1473   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1474   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1475   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1476   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1477   // NamedDecl
1478   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1479   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1480   // ValueDecl
1481   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1482   // DeclaratorDecl
1483   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1484   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1485   // VarDecl
1486   Abv->Add(BitCodeAbbrevOp(0));                       // StorageClass
1487   Abv->Add(BitCodeAbbrevOp(0));                       // StorageClassAsWritten
1488   Abv->Add(BitCodeAbbrevOp(0));                       // isThreadSpecified
1489   Abv->Add(BitCodeAbbrevOp(0));                       // hasCXXDirectInitializer
1490   Abv->Add(BitCodeAbbrevOp(0));                       // isExceptionVariable
1491   Abv->Add(BitCodeAbbrevOp(0));                       // isNRVOVariable
1492   Abv->Add(BitCodeAbbrevOp(0));                       // isCXXForRangeDecl
1493   Abv->Add(BitCodeAbbrevOp(0));                       // isARCPseudoStrong
1494   Abv->Add(BitCodeAbbrevOp(0));                       // isConstexpr
1495   Abv->Add(BitCodeAbbrevOp(0));                       // HasInit
1496   Abv->Add(BitCodeAbbrevOp(0));                   // HasMemberSpecializationInfo
1497   // ParmVarDecl
1498   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsObjCMethodParameter
1499   Abv->Add(BitCodeAbbrevOp(0));                       // ScopeDepth
1500   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ScopeIndex
1501   Abv->Add(BitCodeAbbrevOp(0));                       // ObjCDeclQualifier
1502   Abv->Add(BitCodeAbbrevOp(0));                       // KNRPromoted
1503   Abv->Add(BitCodeAbbrevOp(0));                       // HasInheritedDefaultArg
1504   Abv->Add(BitCodeAbbrevOp(0));                   // HasUninstantiatedDefaultArg
1505   // Type Source Info
1506   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1507   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1508   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1509   DeclParmVarAbbrev = Stream.EmitAbbrev(Abv);
1510 
1511   // Abbreviation for DECL_TYPEDEF
1512   Abv = new BitCodeAbbrev();
1513   Abv->Add(BitCodeAbbrevOp(serialization::DECL_TYPEDEF));
1514   // Redeclarable
1515   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1516   // Decl
1517   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1518   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1519   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1520   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1521   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1522   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1523   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1524   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1525   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1526   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1527   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1528   // NamedDecl
1529   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1530   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1531   // TypeDecl
1532   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1533   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1534   // TypedefDecl
1535   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1536   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1537   DeclTypedefAbbrev = Stream.EmitAbbrev(Abv);
1538 
1539   // Abbreviation for DECL_VAR
1540   Abv = new BitCodeAbbrev();
1541   Abv->Add(BitCodeAbbrevOp(serialization::DECL_VAR));
1542   // Redeclarable
1543   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1544   // Decl
1545   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1546   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1547   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1548   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1549   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1550   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1551   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1552   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1553   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1554   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1555   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1556   // NamedDecl
1557   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1558   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1559   // ValueDecl
1560   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1561   // DeclaratorDecl
1562   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1563   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1564   // VarDecl
1565   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // StorageClass
1566   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // StorageClassAsWritten
1567   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isThreadSpecified
1568   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // CXXDirectInitializer
1569   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isExceptionVariable
1570   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isNRVOVariable
1571   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCXXForRangeDecl
1572   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isARCPseudoStrong
1573   Abv->Add(BitCodeAbbrevOp(0));                         // isConstexpr
1574   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasInit
1575   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasMemberSpecInfo
1576   // Type Source Info
1577   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1578   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1579   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1580   DeclVarAbbrev = Stream.EmitAbbrev(Abv);
1581 
1582   // Abbreviation for EXPR_DECL_REF
1583   Abv = new BitCodeAbbrev();
1584   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_DECL_REF));
1585   //Stmt
1586   //Expr
1587   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1588   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1589   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1590   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1591   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1592   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1593   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1594   //DeclRefExpr
1595   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HasQualifier
1596   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //GetDeclFound
1597   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ExplicitTemplateArgs
1598   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HadMultipleCandidates
1599   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //RefersToEnclosingLocal
1600   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclRef
1601   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1602   DeclRefExprAbbrev = Stream.EmitAbbrev(Abv);
1603 
1604   // Abbreviation for EXPR_INTEGER_LITERAL
1605   Abv = new BitCodeAbbrev();
1606   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_INTEGER_LITERAL));
1607   //Stmt
1608   //Expr
1609   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1610   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1611   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1612   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1613   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1614   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1615   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1616   //Integer Literal
1617   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1618   Abv->Add(BitCodeAbbrevOp(32));                      // Bit Width
1619   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Value
1620   IntegerLiteralAbbrev = Stream.EmitAbbrev(Abv);
1621 
1622   // Abbreviation for EXPR_CHARACTER_LITERAL
1623   Abv = new BitCodeAbbrev();
1624   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_CHARACTER_LITERAL));
1625   //Stmt
1626   //Expr
1627   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1628   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1629   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1630   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1631   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1632   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1633   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1634   //Character Literal
1635   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getValue
1636   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1637   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // getKind
1638   CharacterLiteralAbbrev = Stream.EmitAbbrev(Abv);
1639 
1640   Abv = new BitCodeAbbrev();
1641   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_LEXICAL));
1642   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1643   DeclContextLexicalAbbrev = Stream.EmitAbbrev(Abv);
1644 
1645   Abv = new BitCodeAbbrev();
1646   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_VISIBLE));
1647   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1648   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1649   DeclContextVisibleLookupAbbrev = Stream.EmitAbbrev(Abv);
1650 }
1651 
1652 /// isRequiredDecl - Check if this is a "required" Decl, which must be seen by
1653 /// consumers of the AST.
1654 ///
1655 /// Such decls will always be deserialized from the AST file, so we would like
1656 /// this to be as restrictive as possible. Currently the predicate is driven by
1657 /// code generation requirements, if other clients have a different notion of
1658 /// what is "required" then we may have to consider an alternate scheme where
1659 /// clients can iterate over the top-level decls and get information on them,
1660 /// without necessary deserializing them. We could explicitly require such
1661 /// clients to use a separate API call to "realize" the decl. This should be
1662 /// relatively painless since they would presumably only do it for top-level
1663 /// decls.
1664 static bool isRequiredDecl(const Decl *D, ASTContext &Context) {
1665   // An ObjCMethodDecl is never considered as "required" because its
1666   // implementation container always is.
1667 
1668   // File scoped assembly or obj-c implementation must be seen.
1669   if (isa<FileScopeAsmDecl>(D) || isa<ObjCImplDecl>(D))
1670     return true;
1671 
1672   return Context.DeclMustBeEmitted(D);
1673 }
1674 
1675 void ASTWriter::WriteDecl(ASTContext &Context, Decl *D) {
1676   // Switch case IDs are per Decl.
1677   ClearSwitchCaseIDs();
1678 
1679   RecordData Record;
1680   ASTDeclWriter W(*this, Context, Record);
1681 
1682   // Determine the ID for this declaration.
1683   serialization::DeclID ID;
1684   if (D->isFromASTFile())
1685     ID = getDeclID(D);
1686   else {
1687     serialization::DeclID &IDR = DeclIDs[D];
1688     if (IDR == 0)
1689       IDR = NextDeclID++;
1690 
1691     ID= IDR;
1692   }
1693 
1694   bool isReplacingADecl = ID < FirstDeclID;
1695 
1696   // If this declaration is also a DeclContext, write blocks for the
1697   // declarations that lexically stored inside its context and those
1698   // declarations that are visible from its context. These blocks
1699   // are written before the declaration itself so that we can put
1700   // their offsets into the record for the declaration.
1701   uint64_t LexicalOffset = 0;
1702   uint64_t VisibleOffset = 0;
1703   DeclContext *DC = dyn_cast<DeclContext>(D);
1704   if (DC) {
1705     if (isReplacingADecl) {
1706       // It is replacing a decl from a chained PCH; make sure that the
1707       // DeclContext is fully loaded.
1708       if (DC->hasExternalLexicalStorage())
1709         DC->LoadLexicalDeclsFromExternalStorage();
1710       if (DC->hasExternalVisibleStorage())
1711         Chain->completeVisibleDeclsMap(DC);
1712     }
1713     LexicalOffset = WriteDeclContextLexicalBlock(Context, DC);
1714     VisibleOffset = WriteDeclContextVisibleBlock(Context, DC);
1715   }
1716 
1717   if (isReplacingADecl) {
1718     // We're replacing a decl in a previous file.
1719     ReplacedDecls.push_back(ReplacedDeclInfo(ID, Stream.GetCurrentBitNo(),
1720                                              D->getLocation()));
1721   } else {
1722     unsigned Index = ID - FirstDeclID;
1723 
1724     // Record the offset for this declaration
1725     SourceLocation Loc = D->getLocation();
1726     if (DeclOffsets.size() == Index)
1727       DeclOffsets.push_back(DeclOffset(Loc, Stream.GetCurrentBitNo()));
1728     else if (DeclOffsets.size() < Index) {
1729       DeclOffsets.resize(Index+1);
1730       DeclOffsets[Index].setLocation(Loc);
1731       DeclOffsets[Index].BitOffset = Stream.GetCurrentBitNo();
1732     }
1733 
1734     SourceManager &SM = Context.getSourceManager();
1735     if (Loc.isValid() && SM.isLocalSourceLocation(Loc))
1736       associateDeclWithFile(D, ID);
1737   }
1738 
1739   // Build and emit a record for this declaration
1740   Record.clear();
1741   W.Code = (serialization::DeclCode)0;
1742   W.AbbrevToUse = 0;
1743   W.Visit(D);
1744   if (DC) W.VisitDeclContext(DC, LexicalOffset, VisibleOffset);
1745 
1746   if (!W.Code)
1747     llvm::report_fatal_error(StringRef("unexpected declaration kind '") +
1748                             D->getDeclKindName() + "'");
1749   Stream.EmitRecord(W.Code, Record, W.AbbrevToUse);
1750 
1751   // Flush any expressions that were written as part of this declaration.
1752   FlushStmts();
1753 
1754   // Flush C++ base specifiers, if there are any.
1755   FlushCXXBaseSpecifiers();
1756 
1757   // Note "external" declarations so that we can add them to a record in the
1758   // AST file later.
1759   //
1760   // FIXME: This should be renamed, the predicate is much more complicated.
1761   if (isRequiredDecl(D, Context))
1762     ExternalDefinitions.push_back(ID);
1763 }
1764